Warsaw, Poland

The Polish Academy of science, headquartered in Warsaw, is the top Polish institution having the character of an academy of science. Being a society of distinguished scholars as well as a network of research institutes, it is responsible for spearheading the development of science in Poland. It was established in 1951, during the period of Poland People's Republic. Wikipedia.


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Stronen A.V.,Polish Academy of Sciences | Paquet P.C.,Raincoast Conservation Foundation | Paquet P.C.,University of Victoria
Biological Conservation | Year: 2013

Hybridization processes are widespread throughout the taxonomic range and require conservation recognition. Science can help us understand hybridization processes but not whether and when we ought to conserve hybrids. Important questions include the role of humans in hybridization and the value we place on natural and human-induced hybrids concerning their ecological function. Certain hybrids resulting from human actions have replaced the ecological role of extirpated or extinct parent taxa and this ecological role should be preserved. Conservation policies must increasingly recognize populations of wild organisms that hybridize naturally within the context of their historical ecological role. Natural selection acts on individual organisms and the range of characteristics displayed by individual hybrids constitute raw material for evolution. Guidelines must consider the conservation value of individuals and the ethical aspects of removing hybrids for the purpose of conserving population genetic integrity. Conservation policies should focus on protecting the ecological role of taxa affected by hybridization. An informative example is North American canids (Canis), where body size, prey availability, and human landscape modifications may interact and impose local selective pressures. Gray wolves (Canis lupus) and eastern wolves (Canis lycaon or Canis lupus lycaon) or Great Lakes wolves appear to hybridize naturally within the context of their historical ecological role. In contrast, eastern coyotes (C. latrans) exhibit wolf ancestry and have partly replaced the ecological role of an extirpated parent taxa in parts of northeastern North America. The need for advancing conservation policies that reflect our current understanding of ecology and evolution is urgent. © 2013 Elsevier Ltd.


Skowron A.,University of Warsaw | Stepaniuk J.,University of Bialystok | Swiniarski R.,San Diego State University | Swiniarski R.,Polish Academy of Sciences
Information Sciences | Year: 2012

The results reported in this paper create a step toward the rough set-based foundations of data mining and machine learning. The approach is based on calculi of approximation spaces. In this paper, we present the summarization and extension of our results obtained since 2003 when we started investigations on foundations of approximation of partially defined concepts (see, e.g., [2,3,7,37,20,21,5,42,39,38,40]). We discuss some important issues for modeling granular computations aimed at inducing compound granules relevant for solving problems such as approximation of complex concepts or selecting relevant actions (plans) for reaching target goals. The problems discussed in this article are crucial for building computer systems that assist researchers in scientific discoveries in many areas such as biology. In this paper, we present foundations for modeling of granular computations inside of system that is based on granules called approximation spaces. Our approach is based on the rough set approach introduced by Pawlak [24,25]. Approximation spaces are fundamental granules used in searching for relevant complex granules called as data models, e.g., approximations of complex concepts, functions or relations. In particular, we discuss some issues that are related to generalizations of the approximation space introduced in [33,34]. We present examples of rough set-based strategies for the extension of approximation spaces from samples of objects onto a whole universe of objects. This makes it possible to present foundations for inducing data models such as approximations of concepts or classifications analogous to the approaches for inducing different types of classifiers known in machine learning and data mining. Searching for relevant approximation spaces and data models are formulated as complex optimization problems. The proposed interactive, granular computing systems should be equipped with efficient heuristics that support searching for (semi-)optimal granules. © 2011 Elsevier Inc. All rights reserved.


Kaminski R.,Polish Academy of Sciences
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

The model is presented to describe the f2(1270) meson photoproduction as a result of pion-pion interactions in the final state. Treating tensor mesons as objects dynamically created due to final state interactions is a convenient and straightforward way to employ data from ππ scattering like phase shifts and inelasticities for description of (photo)production reactions while retaining proper analytical structure of amplitudes, two-particle unitarity, and crossing symmetry. The model presented here can provide experimentally testable quantities like differential cross sections and ππ mass distributions as well as the strengths of partial waves corresponding to various f2(1270) helicities which are essential for partial wave analyses. It can also be used to compute moments of angular distribution and spin density matrix elements where partial wave interference effects are important. © 2013 American Physical Society.


Cromsigt J.P.G.M.,University of Oslo | Kuijper D.P.J.,Polish Academy of Sciences
Perspectives in Plant Ecology, Evolution and Systematics | Year: 2011

Browsing lawns, as an analogue of the influential grazing lawn concept, received increased recent interest. We revisit this concept and ask whether the underlying characteristics of a grazing lawn can indeed be generalized to browser-woody plant interactions. Based on previous studies, we define a lawn as a grazed or browsed patch in which intense foraging leads to increased resource availability and a proportional increase of palatable plant species in the patch. We then argue that present examples do not fully support a browsing lawn analogue. Although intense browsing can lead to increased resource availability, it generally reduces the share of palatable plant species in the community. We present an example that does seem to fit both lawn conditions; intensely browsed regeneration patches of palatable trees in Białowieża Primeval forest. Browsing not only prunes these regeneration patches into lawn-like structures, but also increases the share of palatable species in the tree community. Finally, we outline key open issues of the browsing lawn analogue and discuss the discrepancy between our example and the general understanding that browsing reduces the share of palatable tree species. We suggest that lawns are most likely to develop in relatively resource-rich environments where plants can invest in tolerance traits and in situations where herbivores show strong patch selection but are relatively unselective for individual plants within the patch. Although our example fits these conditions, many studies on browser-woody plant interactions come from relatively nutrient poor systems with strong selection for individual palatable trees. More studies in systems similar to our example might show that positive interactions between browsing and the proportion of palatable woody species in a community are not so rare. © 2011 Perspectives in Plant Ecology, Evolution and Systematics.


Kin A.,Society of Friends of Earth science PHACOPS | Blazejowski B.,Polish Academy of Sciences
PloS one | Year: 2014

A new horseshoe crab species, Limulus darwini, is described from the uppermost Jurassic (ca. 148 Ma) near-shore sediments of the Kcynia Formation, central Poland. The only extant species Limulus polyphemus (Linnaeus) inhabits brackish-marine, shallow water environments of the east coast of the United States. Here it is shown that there are no important morphological differences between the Kcynia Formation specimens and extant juvenile representatives of the genus Limulus. The palaeoecological setting inhabited by the new species and the trophic relationships of extant horseshoe crabs are discussed in an attempt to determine the potential range of food items ingested by these Mesozoic xiphosurans. In this paper we propose the adoption of a new term stabilomorphism, this being: an effect of a specific formula of adaptative strategy among organisms whose taxonomic status does not exceed genus-level. A high effectiveness of adaptation significantly reduces the need for differentiated phenotypic variants in response to environmental changes and provides for long-term evolutionary success.


Jaranowski P.,University of Bialystok | Krolak A.,Polish Academy of Sciences
Living Reviews in Relativity | Year: 2012

The article reviews the statistical theory of signal detection in application to analysis of deterministic gravitational-wave signals in the noise of a detector. Statistical foundations for the theory of signal detection and parameter estimation are presented. Several tools needed for both theoretical evaluation of the optimal data analysis methods and for their practical implementation are introduced. They include optimal signal-to-noise ratio, Fisher matrix, false alarm and detection probabilities, F-statistic, template placement, and fitting factor. These tools apply to the case of signals buried in a stationary and Gaussian noise. Algorithms to efficiently implement the optimal data analysis techniques are discussed. Formulas are given for a general gravitational-wave signal that includes as special cases most of the deterministic signals of interest.


Martinez M.,University of Santiago de Compostela | Ryblewski R.,Polish Academy of Sciences | Strickland M.,Gettysburg College | Strickland M.,Frankfurt Institute for Advanced Studies
Physical Review C - Nuclear Physics | Year: 2012

We present results of the application of the anisotropic hydrodynamics (aHydro) framework to (2+1)-dimensional boost-invariant systems. The necessary aHydro dynamical equations are derived by taking moments of the Boltzmann equation using a momentum-space anisotropic one-particle distribution function. We present a derivation of the necessary equations and then proceed to numerical solutions of the resulting partial differential equations using both realistic smooth Glauber initial conditions and fluctuating Monte Carlo Glauber initial conditions. For this purpose we have developed two numerical implementations: one that is based on straightforward integration of the resulting partial differential equations supplemented by a two-dimensional weighted Lax-Friedrichs smoothing in the case of fluctuating initial conditions and another that is based on the application of the Kurganov-Tadmor central scheme. For our final results we compute the collective flow of the matter via the laboratory-frame energy-momentum tensor eccentricity as a function of the assumed shear viscosity-to-entropy ratio, proper time, and impact parameter. © 2012 American Physical Society.


Korelc J.,University of Ljubljana | Stupkiewicz S.,Polish Academy of Sciences
International Journal for Numerical Methods in Engineering | Year: 2014

SUMMARY: A new method to compute numerically efficient closed-form representation of matrix exponential and its derivative is developed for 3×3 matrices with real eigenvalues. The matrix exponential is obtained by automatic differentiation of an appropriate scalar generating function in a general case, and highly accurate asymptotic expansions are derived for special cases in which the general formulation exhibits ill-conditioning, for instance, for almost equal eigenvalues. Accuracy and numerical efficiency of the closed-form matrix exponential as compared with the truncated series approximation are studied. The application of the closed-form matrix exponential in the finite-strain elastoplasticity is also presented. To this end, several time-discrete evolution laws employing the exponential map are discussed for J2 plasticity with isotropic hardening and nonlinear kinematic hardening of Armstrong-Frederick type. The discussion is restricted to the case of elastic isotropy and implicit time integration schemes. In this part, the focus is on a general automatic differentiation-based formulation of finite-strain plasticity models. Numerical efficiency of the corresponding incremental schemes is studied in the context of the FEM. © 2014 John Wiley & Sons, Ltd.


Kaundal R.,Samuel Roberts Noble Foundation | Saini R.,Polish Academy of Sciences | Zhao P.X.,Samuel Roberts Noble Foundation
Plant Physiology | Year: 2010

A complete map of the Arabidopsis (Arabidopsis thaliana) proteome is clearly a major goal for the plant research community in terms of determining the function and regulation of each encoded protein. Developing genome-wide prediction tools such as for localizing gene products at the subcellular level will substantially advance Arabidopsis gene annotation. To this end, we performed a comprehensive study in Arabidopsis and created an integrative support vector machine-based localization predictor called AtSubP (for Arabidopsis subcellular localization predictor) that is based on the combinatorial presence of diverse protein features, such as its amino acid composition, sequence-order effects, terminal information, Position-Specific Scoring Matrix, and similarity search-based Position-Specific Iterated-Basic Local Alignment Search Tool information. When used to predict seven subcellular compartments through a 5-fold cross-validation test, our hybrid-based best classifier achieved an overall sensitivity of 91% with high-confidence precision and Matthews correlation coefficient values of 90.9% and 0.89, respectively. Benchmarking AtSubP on two independent data sets, one from Swiss-Prot and another containing green fluorescent protein- and mass spectrometry-determined proteins, showed a significant improvement in the prediction accuracy of species-specific AtSubP over some widely used "general" tools such as TargetP, LOCtree, PA-SUB, MultiLoc, WoLF PSORT, Plant-PLoc, and our newly created All-Plant method. Cross-comparison of AtSubP on six nontrained eukaryotic organisms (rice [Oryza sativa], soybean [Glycine max], human [Homo sapiens], yeast [Saccharomyces cerevisiae], fruit fly [Drosophila melanogaster], and worm [Caenorhabditis elegans]) revealed inferior predictions. AtSubP significantly outperformed all the prediction tools being currently used for Arabidopsis proteome annotation and, therefore, may serve as a better complement for the plant research community. A supplemental Web site that hosts all the training/testing data sets and whole proteome predictions is available at http://bioinfo3.noble.org/AtSubP/. © 2010 American Society of Plant Biologists.


Losy J.,Polish Academy of Sciences
Journal of Neural Transmission | Year: 2013

Multiple sclerosis (MS) is characterized by multiple areas of inflammation, demyelination and neurodegeneration. Multiple molecular and cellular components mediate neuroinflammation in MS. They involve: adhesion molecules, chemokines, cytokines, matalloproteases and the following cells: CD4+ T cells, CD8+ T cells, B cells, microglia and macrophages. Infiltrating Th1 CD4+ T cells secrete proinflammatory cytokines. They stimulate the release of chemokines, expression of adhesion molecules and can be factors that cause damage to the myelin sheath and axons. Chemokines stimulate integrin activation, mediate leukocyte locomotion on endothelial cells and participate in transendothelial migration. CD8+ cells can directly damage axons. B cells are involved in the production of antibodies which can participate in demyelination. B cells can also function as antigen presenting cells and contribute to T cell activation. Neuroinflammation is not only present in relapsing-remitting MS, but also in the secondary and primary progressive forms of the disease. The association between inflammation consisting of T cells, B cells, plasma cells and macrophages and axonal injury exists in MS patients including the progressive forms of the disease. The above association does not exclude the possibility that neurodegeneration can exist independently from inflammation. Very little inflammation is seen in cortical MS plaques. Anti-inflammatory therapies with different mode of action change the course of MS. Anti-inflammatory and immunomodulatory treatments are beneficial in the early relapsing stage of MS, but these treatments are ineffective in secondary progressive and primary progressive MS. In the stage of progressive MS, inflammation becomes trapped behind a closed or repaired blood-brain barrier. In such a situation current immunomodulatory, immunosuppressive or anti-inflammatory treatments might not reach this inflammatory process to exert a beneficial effect. © 2013 The Author(s).


Grant
Agency: Cordis | Branch: H2020 | Program: MSCA-RISE | Phase: MSCA-RISE-2014 | Award Amount: 2.31M | Year: 2015

European particle physics groups interested in searching signals of new physics both with neutrinos, at T2K experiment, and at the intensity frontier, with the Belle-II experiment at the SUPERKEKB machine, want to share between them and with KEK laboratory their knowledge in data analysis and detector technologies. Such knowledge sharing will enhance skills and competences of all participants, will allow Europe to play a primary role in the search for deviations from the actually known fundamental physics in the flavour sector and, last but not least, will produce an unprecedented collaboration with japanese scientists on the ground of dissemination and outreach.


Grant
Agency: Cordis | Branch: FP7 | Program: CPCSA | Phase: INFRA-2008-1.2.2 | Award Amount: 3.70M | Year: 2009

A coherent classification and species checklist of the worlds plants, animals, fungi and microbes is fundamental for accessing information about biodiversity. The Catalogue of Life provides the world with a unique service: a dynamically updated global index of validated scientific names, synonyms and common names integrated within a single taxonomic hierarchy.The Catalogue of Life was initiated as a European Scientific Infrastructure under FP5 and has a distributed knowledge architecture. Its federated e-compendium of the worlds organisms grows rapidly (now covering well over one million species), and has established a formidable user base, including major global biodiversity portals as well as national biodiversity resources and individual users worldwide.Joint Research Activities in this 4D4Life Project will establish the Catalogue of Life as a state of the art e-science facility based on an enhanced service-based distributed architecture. This will make it available for integration into analytical and synthetic distributed networks such as those developing in conservation, climate change, invasive species, molecular biodiversity and regulatory domains. User-driven enhancements in the presentation of distribution data and bio-data will be made.In its Networking Activities 4D4Life will strengthen the development of Global Species Databases that provide the core of the service, and extend the geographical reach of the programme beyond Europe by realizing a Multi-Hub Network integrating data from China, New Zealand, Australia, N. America and Brazil.Service Activities, the largest part of 4D4Life, will create new electronic taxonomy services, including synonymy server, taxon name-change, and download services, plus new educational and popular services, for instance for hand-held devices.


Grant
Agency: Cordis | Branch: FP7 | Program: CP-CSA-Infra | Phase: INFRA-2008-1.1.1 | Award Amount: 32.30M | Year: 2009

Particle physics stands at the threshold of a new era of discovery and insight. Results from the much awaited LHC are expected to shed light on the origin of mass, supersymmetry, new space dimensions and forces. In July 2006 the European Strategy Group for Particle Physics defined accelerator priorities for the next 15 years in order to consolidate the potential for discovery and conduct the required precision physics. These include an LHC upgrade, R&D on TeV linear colliders and studies on neutrino facilities. These ambitious goals require the mobilisation of all European resources to face scientific and technological challenges well beyond the current state-of-the-art and the capabilities of any single laboratory or country. EuCARD will contribute to the formation of a European Research Area in accelerator science, effectively creating a distributed accelerator laboratory across Europe. It will address the new priorities by upgrading European accelerator infrastructures while continuing to strengthen the collaboration between its participants and developing synergies with industrial partners. R&D will be conducted on high field superconducting magnets, superconducting RF cavities which are particularly relevant for FLASH, XFEL and SC proton linacs, two-beam acceleration, high efficiency collimation and new accelerator concepts. EuCARD will include networks to monitor the performance and risks of innovative solutions and to disseminate results. Trans-national access will be granted to users of beams and advanced test facilities. Strong joint research activities will support priority R&D themes. As an essential complement to national and CERN programmes, the EuCARD proposal will strengthen the European Research Area by ensuring that European accelerator infrastructures further improve their performance and remain at the forefront of global research, serving a community of well over 10,000 physicists from all over the world.


Grant
Agency: Cordis | Branch: H2020 | Program: MSCA-RISE | Phase: MSCA-RISE-2015 | Award Amount: 1.33M | Year: 2016

Increasingly challenging global and environmental requirements have resulted in agricultural systems coming under increasing pressure to enhance their resilience capabilities in order to respond to the abrupt changes in resource quality, quantity and availability, especially during unexpected environmental circumstances, such as uncertain weather, pests and diseases, volatile market conditions and commodity prices. Therefore, integrated solutions are necessary to support the whole food agricultural life-cycle value chain. Solutions necessarily must consider the products cycle, as well as each of the value chain stages. Thus, managing risks and the uncertain availability of information will lead farmers to take advantage of these managerial, technical and social based-solutions. This implies the need for innovative technology-based knowledge management system to capture the agricultural information, at a variety of regional locations, in terms of collecting, storing, processing, and disseminating information about uncertain environmental conditions that affect agricultural decision-making production systems. Hence, from the genetic design of the seed, till their planting and harvest processes, RUCAPS provides knowledge of the full agricultural life-cycle based-decision making process to realise the key impacts of every stage of the agriculture-related processes. Therefore, RUCAPS implies the development of a high impact research project in order to integrate real-life based agriculture requirements, alternative land management scenarios, unexpected weather and environmental conditions as well as supporting innovation in the development of agriculture production systems, operations, logistics and supply chain management and the impact of these systems and processes over the end-users and customers. This is to be conceived through the integration of standard and customised solutions for facilitating the collaborative engagement within the agriculture value chain.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA-SA | Phase: INCO.2012-2.2 | Award Amount: 838.09K | Year: 2012

The major objectives of BILAT-UKR*AINA are to support the institutional dialogue on STI policy between the European Commission, the EU MS, CC and AC, and Ukraine, to provide analytical input to the dialogue at the JSTCC and to ensure practical follow-up and sustainability; Particularly, BILAT-UKR*AINA foresees in a flexible manner pilot activities to facilitate the implementation of the joint EU-Ukraine STI Roadmap; promotes RTDI cooperation opportunities to support the creation of networks and the participation in joint projects; monitors and analyses innovation and research cooperation expressed in co-publications, scientific and educational networks and in terms of joint projects; analyses, promotes and monitors the participation of EU researchers in Ukrainian S&T State Programmes; secures the outreach of the project to interested parties who are not consortium members and increases awareness about the assets of RTDI cooperation with Ukraine. The consortium is supported by the key stakeholders from the target country: the responsible Ministry, the State Agency, the National Information Point and the National Academy of Sciences - who are either project partners or members of the advisory board. Most partners have already cooperated in the preceding BILAT-UKR project and present herewith an Advanced INnovative Approach within BILAT-UKR*AINA.


Grant
Agency: Cordis | Branch: H2020 | Program: RIA | Phase: INFRAIA-1-2014-2015 | Award Amount: 10.00M | Year: 2016

ENSAR2 is the integrating activity for European nuclear scientists who are performing research in three of the major subfields defined by NuPECC: Nuclear Structure and Dynamics, Nuclear Astrophysics and Nuclear Physics Tools and Applications. It proposes an optimised ensemble of Networking (NAs), Joint Research (JRAs) and Transnational Access Activities (TAs), which will ensure qualitative and quantitative improvement of the access provided by the current ten infrastructures, which are at the core of this proposal. The novel and innovative developments that will be achieved by the RTD activities will also assure state-of-the-art technology needed for the new large-scale projects. Our community of nuclear scientists profits from the diverse range of world-class research infrastructures all over Europe that can supply different ion beams and energies and, with ELI-NP, high-intensity gamma-ray beams up to 20 MeV. We have made great effort to make the most efficient use of these facilities by developing the most advanced and novel equipment needed to pursue their excellent scientific programmes and applying state-of-the-art developments to other fields and to benefit humanity (e.g. archaeology, medical imaging). Together with multidisciplinary and application-oriented research at the facilities, these activities ensure a high-level socio-economic impact. To enhance the access to these facilities, the community has defined a number of JRAs, using as main criterion scientific and technical promise. These activities deal with novel and innovative technologies to improve the operation of the facilities. The NAs of ENSAR2 have been set-up with specific actions to strengthen the communities coherence around certain resarch topics and to ensure a broad dissemination of results and stimulate multidisciplinary, application-oriented research and innovation at the Research Infrastructures.


Grant
Agency: Cordis | Branch: H2020 | Program: RIA | Phase: ICT-30-2015 | Award Amount: 7.33M | Year: 2016

INTER-IoT project is aiming at the design, implementation and experimentation of an open cross-layer framework and associated methodology to provide voluntary interoperability among heterogeneous Internet of Things (IoT) platforms. The proposal will allow developing effectively and efficiently smart IoT applications, atop different heterogeneous IoT platforms, spanning single and/or multiple application domains. The overall goal of the INTER-IoT project is to provide a interoperable framework architecture for seamless integration of different IoT architectures present in different application domains. Interoperability will be provided at different levels: device, network, middleware, services and data. The two application domains and use cases addressed in the project and in which the IoT framework will be applied are m-health and port transportation and logistics. The project outcome may optimize different operations (e.g. increasing efficiency in transportation time; reducing CO2 emission in a port environment; improving access control and safety; improving remote patient attendance and increase the number of subject that surgery units can assist using the mobile devices with the same resources; reducing time spent in hospitals premises or reduce the time dedicated to the assistance activities carried out directly at the surgery with advantage for subjects in charge and also benefits those waiting, i.e. reduction of the waiting list) in the two addresses domains, but it may be extended to other application domains in which there is a need to interconnect different IoT architectures already deployed. The project may deal with interoperability at different layers.


Grant
Agency: Cordis | Branch: FP7 | Program: CP | Phase: ENV.2012.6.4-1 | Award Amount: 6.77M | Year: 2012

Urban regions in the EU face increasing but uncertain flood risks due to urbanization and the effects of climate change. In European (a.o. the Flood Risk Directive) and in national and regional policies, attempts are made to diversify and align different Flood Risk Strategies (FRSs). In our proposal, five such strategies are distinguished: risk prevention; flood defense; mitigation; preparation; and recovery. We assume that vulnerable urban agglomerations will be more resilient if multiple FRSs are applied simultaneously, linked together and aligned. At the same time, the application of a diverse cluster of FRSs has to be appropriate, i.e. attuned to the physical and social context. The latter asks for innovative Flood Risk Governance Arrangements (FRGAs). In the proposed program, insights from governance and legal scholars will be integrated and combined, leading to policy design principles for FRGAs as well as concrete recommendations for policy and law at the level of the EU, its member states, regional authorities, and public-private partnerships. Across different EU countries and regions, we expect to identify different mixes of FRSs. We will analyze, explain and evaluate the emergence and dominance of the FRGAs through which these FRSs are institutionally embedded. For this, a comparative analysis of FRGAs in six EU member states will be carried out. This analysis will reveal good practices, provide understanding of the resilience of FRSs as well as their appropriateness in different physical, social and legal contexts. The design principles thus derived, will be brought together in a design-oriented framework for ex-ante evaluation of FRGAs. As part of the program, various target group specific knowledge dissemination activities will be carried out, aimed at regional stakeholders, high level policymakers and EU officers. To this end, Grontmij, a consultancy company, and CEPRI (The European centre for flood risk prevention) have been included in the consortium, apart from universities in the six EU member states.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA-CA | Phase: INCO-2007-3.1.2 | Award Amount: 2.86M | Year: 2009

Strategic Objectives Assessed: Strengthening the ERA by integrating national and European S&T schemes through International Cooperation in S&T with Korea, with a specific focus on existing Competency Networks.


Grant
Agency: Cordis | Branch: FP7 | Program: CP-CSA-Infra | Phase: INFRA-2007-2.2-01 | Award Amount: 8.77M | Year: 2007

The SPIRAL 2 Preparatory Phase project aims to achieve the development and signing of the consortium agreement allowing for the construction of the facility. The SPIRAL 2 project located at the GANIL facility (Caen, France) will deliver energetic rare (radioactive) isotope beams with intensities not yet available with presently running machines. The studies of the properties of nuclei forming these beams or their interaction with stable nuclei is a rapidly developing field of contemporary nuclear physics, astrophysics and interdisciplinary research. Although the Region Basse-Normandie and the French funding agencies (CNRS and CEA) are financing the investment to the extend of 80% of the cost of baseline project, SPIRAL 2 seeks new partners in order to balance the construction budget both of the baseline project and of the new instrumentation necessary for experiments. The Preparatory Phase will deal with the critical financial, legal and organisational issues related to the international character of the SPIRAL 2 facility during its construction and operation phases. Searching for new funding partners will be achieved by direct contacts and negotiations between international partners, their funding agencies and the European Commission as established through the official visits, meetings and workshops. Several critical technical issues have still to be addressed in order to construct the SPIRAL2 facility and associated instrumentation. The corresponding tasks were chosen in order solve remaining technical challenges as well as to attract efficiently European partners. In particular, the accent was put on the new instrumentation for SPIRAL 2. This topic, being the most attractive for scientists, is an excellent tool to convince the funding agencies of international partners to commit for the construction phase. The attractiveness of SPIRAL 2 for outside users will be improved by the construction of new infrastructures.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA-SA | Phase: INCO-2007-2.1 | Award Amount: 598.12K | Year: 2008

The main objectives of BILAT-UKR are: - to strengthen the S&T cooperation between the EU and Ukraine in particular through a stronger participation of Ukraine in FP7 and other Community programmes and initiatives. - to further improve the framework for enhanced future and sustainable S&T cooperation, especially regarding legal and funding issues. - to provide a knowledge base for new cooperation themes and priority areas, and for emerging horizontal issues of sustainable cooperation, especially in the fields of scientific mobility, innovation and infrastructure. - to provide support for the working groups set up to organize a thematic and high level policy dialogue between the Ministry of Education and Science of Ukraine and the European Commission. The consortium gathers 11 various institutions of 7 countries (amongst which 2 Ukrainian neighbours), having a long-standing experience in international S&T cooperation. The project can draw on and complement the experience the partners have gained in several cooperation projects under FP6 or FP7. BILAT-UKR will provide a new momentum to improve the participation of Ukrainian scientists to FP7, and will prepare the ground for a possible association of Ukraine to FP7. The proposal is also expected to have an impact on the implementation of the S&T dimension of the European Neighbouring policy.


Grant
Agency: Cordis | Branch: H2020 | Program: CSA | Phase: INFRADEV-03-2016-2017 | Award Amount: 3.88M | Year: 2017

The objectives of the IDEAAL Project are to explore all possibilities to develop GANIL infrastructure, with its new ESFRI SPIRAL2 facility, in order to ensure its long-term sustainability as one of the premiere European research institutes for nuclear physics, interdisciplinary sciences and related applications. The first objective of the IDEAAL Project is to enlarge the present GANIL membership to include academic institutions and private funding partners. This enlargement goes hand-in-hand with a reinforcement of the involvement of the current institutional funders and academic users of GANIL-SPIRAL2 in the decision-making process and management of the facility. The second objective of IDEAAL is to enhance the excellence of access to the infrastructure by optimizing support to the users, access policy, assessment on the cost of access to the facilities and to data, improvement of the performance capabilities as well as exchange and training of personnel with associated partners. Innovation is the third objective of IDEAAL. With the new facility SPIRAL2, it is essential to encourage industrial users of the uniqueness of this new machine for their research and applications and to allow them to develop new experimental tools at the existing GANIL facilities. Access provision dedicated to industrial users will greatly enhance their experience and increase their interest and trust in GANIL-SPIRAL2. In parallel, new ideas and topics for technology transfer will be clearly identified. The increase of innovation potential of GANIL will also be evaluated. These three objectives must be supported by a strong communication and outreach policy towards members and funding partners, users and the layman. This is the fourth objective of the project. Fulfilling all of these four objectives will allow a well-organized, highly efficient and sustainable development of the current GANIL structure.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA-CA | Phase: INCO.2012-1.4 | Award Amount: 4.55M | Year: 2012

SEA-EU-NET 2 will build upon and leverage strong EU-SEA S&T relationships developed through past support and coordination actions, to deepen engagement and build momentum in S&T cooperation. It broadens the scope of EU-SEA cooperation through stimulating sustainable innovation collaborations. SEA-EU-NET 2 will focus on three societal challenges: Health, Food security and safety, and Water management, where the greatest opportunities can be leveraged from joint EU-SEA research. SEA-EU-NET 2 will serve as a platform for all stakeholders across governments, funders, practitioners, and the private sector, to ensure a complete and integrated approach to developing sustainable STI collaboration to jointly tackle societal challenges. It will focus on: Dialogue: To strengthen bi-regional and bilateral EU-ASEAN dialogues in S&T cooperation Decision-Making: To report to policy makers in both Europe and Southeast Asia in order to pave the way to implement new ambitious bi-regional activities in STI Jointly Tackling Societal Challenges: To focus on joint efforts on a selected set of thematic areas, namely Health, Food security and safety, and Water management. In focussing on these topics, the project will evaluate EU-SEA S&T cooperation, run workshops to bring scientists together, support young scientists develop new funding schemes to broaden and deepen the collaboration Networking: To network different stakeholders to build bi-regional networks and to strengthen research capacity Sustainability: To ensure that all activities deliver impact beyond the lifespan of the project in order to develop sustainable partnerships The project will have lasting impact on (1) a structured and substantiated policy dialogue between ASEAN and EU, (2) the promotion of the ERA in SEA, (3) the role of EU as major partner in research cooperation and innovation by jointly tackling societal challenges, (4) the development of new funding schemes in research and academic mobility


Grant
Agency: Cordis | Branch: FP7 | Program: CP-CSA-Infra | Phase: INFRA-2010-1.1.32 | Award Amount: 11.03M | Year: 2010

ENSAR is the Integrating Activity of Nuclear Scientists from almost all European countries performing research in three of the major subfields of Nuclear Physics: Nuclear Structure, Nuclear Astrophysics and Applications of Nuclear Science. It proposes an optimised ensemble of Networking (NAs), Transnational Access and Joint Research Activities (JRAs), which will ensure qualitative and quantitative improvement of the access provided by the current seven infrastructures, which are at the core of this proposal. The novel and innovative developments that will be achieved by the RTD activities will also assure state-of-the-art technology needed for the new large-scale projects. Our community of nuclear scientists profits from the diverse range of world-class research infrastructures in Europe that can supply different ion beams and energies. We have made great efforts to make the most efficient use of these facilities by developing the most advanced and novel equipment needed to pursue their excellent scientific programmes and applying state-of-the-art developments in nuclear instrumentation to other research fields and to benefit humanity (e.g. archaeology, medical imaging). Together with multidisciplinary and application-oriented research at the facilities these activities ensure a high-level socioeconomic impact. To enhance the access to these facilities, the community has defined a number of JRAs, using as main criterion scientific and technical promise. These activities deal with novel and innovative technologies to improve the operation of the facilities. In addition, a key JRA aims at integrating the laboratories in Central and South-Eastern European countries with those elsewhere in Europe. The NAs of ENSAR have been set-up with specific actions to strengthen the communities coherence around certain research topics and to ensure a broad dissemination of results and stimulate multidisciplinary and application-oriented research at the Research Infrastructures.


Grant
Agency: Cordis | Branch: FP7 | Program: CP-CSA-Infra | Phase: INFRA-2008-1.1.2 | Award Amount: 11.23M | Year: 2009

ULICE is a 4-year project set up by 20 leading European research organisations, including 2 leading European industrial partners (Siemens and IBA), to respond to the need for greater access to hadron therapy facilities for particle therapy research. Project coordinator is the Italian Research Infrastructure Facility CNAO (Milan). Both existing European Hadron Research Facilities in Heidelberg and Milan are partner and together with the next operational centre (Philipps-Universitt Marburg; yr4) they will provide 624 hours of beam-time (141 users, 52 projects) to external researchers. Future facilities like MedAustron, Etoile and Archade also participate in ULICE, which will result in a strong integrated network. Full exploitation of all different resources, unrestricted spread of information and the improvement of existing and upcoming facilities are provided by using grid-based data sharing. The project is built around 3 pillars with measurable outputs. These outputs will be exploited by the (future) facilities and (partly by) the industrial partners: 1. JRA - focus on development of instruments and protocols: new gantry design, improvement of four-dimensional particle beam delivery, adaptive treatment planning, mechanisms for patient selection to the whole European Community and database development for specific tumours which can best be treated using carbon ion. 2. Networking - increasing cooperation between facilities and research communities wanting to work with the research infrastructure. Outputs will be (among others): a report on recommendations for strategically optimal locations for future RIs throughout Europe, training to new users 3. Transnational access: 2-step approach, using a combination of pre-defined (within ULICE) clinical trial programmes to allow researchers with patients to visit the facility, and radiobiological and physics experiments to take place.


Grant
Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: HEALTH-2007-1.2-2 | Award Amount: 7.53M | Year: 2008

The proposal aims at the development and clinical validation of advanced non-invasive optical methodologies for in-vivo diagnosis, monitoring, and prognosis of major neurological diseases (stroke, epilepsy, ischemia), based on diffuse optical imaging by pulsed near infrared light. Established diagnostic imaging modalities (e.g. X-ray Computed Tomography, Magnetic Resonance Imaging, Positron Emission Tomography) provide 3D anatomical, functional or pathological information with spatial resolution in the millimetre range. However, these methods cannot be applied continuously or at the bedside. Diffuse optical imaging is expected to provide a valuable complementing tool to assess perfusion and blood oxygenation in brain tissue and their time evolution in a continuous or quasi-continuous manner. The devices will be portable and comparably inexpensive and can be applied in adults and in children. Time-domain techniques are acknowledged as offering superior information content and sensitivity compared to other optical methods, allowing for separation between contributions of surface tissues (skin and skull) and brain tissue. Time-domain imaging can also differentiate between the effects of scatter and those of absorption.The consortium plans major developments in technology and data analysis that will enhance time-domain diffuse optical imaging with respect to spatial resolution, sensitivity, robustness of quantification as well as performance of related instruments in clinical diagnosis and monitoring. The diagnostic value of time-domain diffuse optical imaging will be assessed by clinical pilot studies addressing specific neurological disorders, in comparison with established neurophysiological and neuroimaging techniques. Perspectives regarding clinical application of time-domain diffuse optical brain imaging will be estimated and a reliable basis for a potential commercialisation of this novel technique by European system manufacturers will be created.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA-CA | Phase: INCO-2007-1.6 | Award Amount: 4.72M | Year: 2008

SEA-EU-NET will increase the quality, quantity, profile and impact of the bi-regional S&T cooperation between SEA countries of ASEAN and MS and AS of EU. S&T, essential for a strong knowledge-based economy, underpins policies necessary for governance, and contributes to cohesive social visions and models. S&T excellence also requires global connectivity and an ongoing dialogue. This proposal supports the internationalisation policy of EU and objectives of FP7 of EU. It contributes to S&T foundation essential to the EUs political, economic and social objectives. There is great potential in strengthening the participation of SEA in FP7 and for a conjoint European involvement in SEA S&T. Constraining factors include insufficient awareness of opportunities, inadequate connections amongst researchers, establishing partnerships, complexity of S&T programs, and the asynchronous funding systems. Thus increased SEA-EU cooperation requires targeted measures integrating and strengthening the S&T dialogue in a coherent way. The SEA-EU-NET will deliver measures to increase SEA-EU cooperation amongst academic, industrial and government stakeholders. Measures include implementation of joint for a strengthening the bi-regional and bilateral dialogue, analysing S&T structures, reporting to EU-presidencies thus incorporating recent political developments, and generally highlighting EU-ASEAN initiatives. In addition the project builds a network of stakeholders in the SEA region while at the same time linking it to other existing and upcoming ERA-, INCO-NET, and thematic EU-FP projects thus facilitating the development of a coherent EU-level approach on international S&T cooperation. Based on these structures SEA-EU-NET will also address global issues of mutual interest in regards to the challenges of the globalisation of research and reaching the global Millennium Goals by recommending joint S&T related activities and developing joint scenarios.


Grant
Agency: Cordis | Branch: FP7 | Program: CP-CSA-Infra-PP | Phase: INFRA-2010-2.2.11 | Award Amount: 9.59M | Year: 2011

The main objective of TIARA (Test Infrastructure and Accelerator Research Area) is the integration of national and international accelerator R&D infrastructures into a single distributed European accelerator R&D facility. This will include the implementation of organisational structures to enable the integration of existing individual infrastructures, their efficient operation and upgrades, and the construction of new infrastructures as part of TIARA. TIARA will enable full exploitation of the complementary features and expertise of the individual member infrastructures, maximizing the benefits for both the owners of these infrastructures and their users. This unique distributed facility will also support the development of an integrated R&D programme embracing the needs of many different fields, as well as medical and industrial sectors, both on technical and human resource aspects. Besides a world-level state-of-the-art distributed R&D facility, TIARA will develop means for establishing and supporting joint accelerator R&D programming, joint education and training programmes and strengthened collaboration with industry. TIARA-PP will deliver a sustainable coordinated European framework for the benefit of - the different fields of science, which need state-of-the-art and/or cost effective accelerators to carry out their research programme - the implementation of the accelerator-based infrastructures identified in the ESFRI roadmap - the different partners (national laboratories, universities, industry) to develop joint projects and exchange expertise on state-of-the-art technologies - European countries to invest and develop their own infrastructures and research centres as parts of TIARA, within an established Europe-wide coordination framework. - Europe as a whole to ensure world-level leadership in the field of accelerator science and to enable coordinated and efficient means for its regionally balanced scientific and technological development.


Grant
Agency: Cordis | Branch: FP7 | Program: CP | Phase: INFRA-2011-2.1.1. | Award Amount: 10.17M | Year: 2011

Key questions in physics can be answered only by constructing a giant underground observatory to search for rare events and study terrestrial and astrophysical neutrinos. The Astroparticle Roadmap of ApPEC/ASPERA strongly supports this, recommending that: a new large European infrastructure of 100000-500000 ton for proton decay and low-energy neutrinos be evaluated as a common design study together with the underground infrastructure and eventual detection of accelerator neutrino beams. The latest CERN roadmap also states: a range of very important non-accelerator experiments takes place at the overlap of particle and astroparticle physics exploring otherwise inaccessible phenomena; Council will seek with ApPEC a coordinated strategy in these areas of mutual interest. Reacting to this, uniting scientists across Europe with industrial support to produce a very strong collaboration, the LAGUNA FP7 design study has had a very positive effect. It enabled, via study of seven pre-selected locations (Finland, France, Italy, Poland, Romania, Spain and UK), a detailed geo-technical assessment of the giant underground cavern needed, concluding finally that no geo-technical show-stoppers to cavern construction exist. Building on this, the present design study will address two challenges vital to making a final detector and site choice: (i) to determine the full cost of construction underground, commissioning and long-term operation of the infrastructure, and (ii) to determine the full impact of including long baseline neutrino physics with beams from CERN.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA | Phase: INFRA-2007-3.0-03 | Award Amount: 4.06M | Year: 2008

PESI provides standardised and authoritative taxonomic information by integrating and securing Europes taxonomically authoritative species name registers and nomenclators (name databases) that underpin the management of biodiversity in Europe.\nPESI defines and coordinates strategies to enhance the quality and reliability of European biodiversity information by integrating the infrastructural components of four major community networks on taxonomic indexing into a joint work programme. This will result in functional knowledge networks of taxonomic experts and regional focal points, which will collaborate on the establishment of standardised and authoritative taxonomic (meta-) data. In addition PESI will coordinate the integration and synchronisation of the European taxonomic information systems into a joint e-infrastructure and the set up of a common user-interface disseminating the pan-European checklists and associated user-services results\nThe organisation of national and regional focal point networks as projected not only assures the efficient access to local expertise, but is also important for the synergistic promotion of taxonomic standards throughout Europe, for instance to liaison with national governmental bodies on the implementation of European biodiversity legislations. In addition PESI will start with the geographic expansion of the European expertise networks to eventually cover the entire Palaearctic biogeographic region.\nPESI supports international efforts on the development of a Global Names Architecture by building a common intelligent name-matching device in consultation with the principal initiatives (GBIF, TDWG, EoL, SpeciesBase). PESI contributes the development of a unified cross-reference system and provides of high quality taxonomic standards. PESI will further involve the Europe-based nomenclatural services and link the planned joint European taxonomic e-infrastructures middle-layer to the global e-gateway.


News Article | October 25, 2016
Site: phys.org

The nuclei of atoms of heavy elements are not necessarily spherical; they may be variously extended or flattened along one, two or even three axes. An international team of physicists, led by scientists from the Institute of Nuclear Physics of the Polish Academy of Sciences in Krakow (IFJ PAN) and the Heavy Ion Laboratory at the University of Warsaw (HIL), has recently presented the results of experiments showing that complex superdeformed nuclei occur in much lighter elements, as well.


The mutually beneficial relationship between algae and modern corals -- which provides algae with shelter, gives coral reefs their colors and supplies both organisms with nutrients -- began more than 210 million years ago, according to a new study by an international team of scientists including researchers from Princeton University. That this symbiotic relationship arose during a time of massive worldwide coral-reef expansion suggests that the interconnection of algae and coral is crucial for the health of coral reefs, which provide habitat for roughly one-fourth of all marine life. Reefs are threatened by a trend in ocean warming that has caused corals to expel algae and turn white, a process called coral bleaching. Published in the journal Science Advances, the study found strong evidence of this coral-algae relationship in fossilized coral skeletons dating back more than 210 million years to the late Triassic period, a time when the first dinosaurs appeared and Earth's continents were a single land mass known as Pangea. Although symbiosis is recognized to be important for the success of today's reefs, it was less clear that that was the case with ancient corals. "It is important to know how far back in time symbiosis evolved because it gives insight into how important symbiosis is to the health of coral reefs," said Daniel Sigman, Princeton's Dusenbury Professor of Geological and Geophysical Sciences and a member of the Princeton Environmental Institute. "It appears that the origin of symbiosis corresponds to the rise of coral reefs in general." In addition to confirming that symbiosis dates back to the Triassic, the study found that the corals inhabited nutrient-poor marine environments -- not unlike today's subtropical waters -- where algae-coral symbiosis played a major role in driving reef development. "The onset of symbiosis with algae was highly profitable for corals," said lead author Jaroslaw Stolarski, a professor of biogeology at the Institute of Paleobiology at the Polish Academy of Sciences. "It allowed them to survive in very nutrient-poor waters, and at the same time grow and expand." Algae belonging to the group known as dinoflagellates live inside the corals' tissues. The algae use photosynthesis to produce nutrients, many of which they pass to the corals' cells. The corals in turn emit waste products in the form of ammonium, which the algae consume as a nutrient. This relationship keeps the nutrients recycling within the coral rather than drifting away in ocean currents and can greatly increase the coral's food supply. Symbiosis also helps build reefs -- corals that host algae can deposit calcium carbonate, the hard skeleton that forms the reefs, up to 10 times faster than non-symbiotic corals. Finding out when symbiosis began has been difficult because dinoflagellates have no hard or bony parts that fossilize. Instead, the researchers looked for three types of signatures in the coral fossils that indicate the past presence of algae: fossil microstructures, levels of different types of carbon and oxygen, and levels of two forms of nitrogen. First author Katarzyna Frankowiak of the Institute of Paleobiology at the Polish Academy of Sciences conducted the microstructural analysis with assistance from Marcelo Kitahara of the Federal University of Sao Paulo in Brazil, Maciej Mazur of the University of Warsaw, and Anders Meibom of the Ecole Polytechnique Federale de Lausanne and the Universite de Lausanne. Their analysis revealed regularly spaced patterns of growth consistent with the symbiotic corals' reliance on algal photosynthesis, which only takes place during daylight. Frankowiak and Anne Gothmann, who earned her Ph.D. from Princeton's Department of Geosciences in 2015 and is now a postdoctoral researcher at the University of Washington, measured the ratios of different types of oxygen and carbon and found that the results matched what would be expected when symbiosis occurs. The third approach, determining the forms of nitrogen -- which derive in part from the ammonium the corals had excreted -- was conducted by Xingchen (Tony) Wang, who earned his doctoral degree in geosciences from Princeton in 2016 and is now a postdoctoral research fellow working with Sigman. The nitrogen atoms, which are trapped in the fossil's calcium-carbonate matrix, come in two forms, or isotopes, that vary only by how many neutrons they have: 14N has seven neutrons while 15N has eight neutrons, making it slightly heavier. By studying modern corals, researchers knew that symbiotic corals contain a lower ratio of 15N to 14N compared to non-symbiotic corals. The team found that the fossilized corals also had a low 15N-to-14N ratio, indicating they were symbiotic. "Although algae were not present in the fossils, they left behind chemical signatures," Wang said. "We found strong evidence that the fossilized coral were symbiotic and that they lived in a nutrient-poor environment. We were able to link the environmental conditions from 200 million years ago to the evolution of corals." George Stanley, a professor of geosciences at the University of Montana, had earlier explored the question of when symbiosis first evolved in corals. "This confirms a hypothesis that my colleagues and I put forth 20 years ago," said Stanley, who is familiar with the research but had no role in it. "It is really exciting to see this confirmation." The fossils used in the study were collected in a mountainous region in Antalya, Turkey. During their lifetime, they lived in a shallow sunlit body of water called the Tethys Sea. Stanley said the work would not have been possible without the coral fossils, which were remarkably well-preserved. "These corals are such a wonderful resource because they are as if you picked them up off the beach yesterday, and this is because they were sealed in deposits for centuries." The fossil record also shows a significant reef expansion occurred around 205 million years ago, and this fits with a boost in coral growth due to the development of symbiosis, Stanley said. Additional photos related to this research can be found here.


News Article | November 3, 2016
Site: www.sciencedaily.com

The mutually beneficial relationship between algae and modern corals -- which provides algae with shelter, gives coral reefs their colors and supplies both organisms with nutrients -- began more than 210 million years ago, according to a new study by an international team of scientists including researchers from Princeton University. That this symbiotic relationship arose during a time of massive worldwide coral-reef expansion suggests that the interconnection of algae and coral is crucial for the health of coral reefs, which provide habitat for roughly one-fourth of all marine life. Reefs are threatened by a trend in ocean warming that has caused corals to expel algae and turn white, a process called coral bleaching. Published in the journal Science Advances, the study found strong evidence of this coral-algae relationship in fossilized coral skeletons dating back more than 210 million years to the late Triassic period, a time when the first dinosaurs appeared and Earth's continents were a single land mass known as Pangea. Although symbiosis is recognized to be important for the success of today's reefs, it was less clear that that was the case with ancient corals. "It is important to know how far back in time symbiosis evolved because it gives insight into how important symbiosis is to the health of coral reefs," said Daniel Sigman, Princeton's Dusenbury Professor of Geological and Geophysical Sciences and a member of the Princeton Environmental Institute. "It appears that the origin of symbiosis corresponds to the rise of coral reefs in general." In addition to confirming that symbiosis dates back to the Triassic, the study found that the corals inhabited nutrient-poor marine environments -- not unlike today's subtropical waters -- where algae-coral symbiosis played a major role in driving reef development. "The onset of symbiosis with algae was highly profitable for corals," said lead author Jaroslaw Stolarski, a professor of biogeology at the Institute of Paleobiology at the Polish Academy of Sciences. "It allowed them to survive in very nutrient-poor waters, and at the same time grow and expand." Algae belonging to the group known as dinoflagellates live inside the corals' tissues. The algae use photosynthesis to produce nutrients, many of which they pass to the corals' cells. The corals in turn emit waste products in the form of ammonium, which the algae consume as a nutrient. This relationship keeps the nutrients recycling within the coral rather than drifting away in ocean currents and can greatly increase the coral's food supply. Symbiosis also helps build reefs -- corals that host algae can deposit calcium carbonate, the hard skeleton that forms the reefs, up to 10 times faster than non-symbiotic corals. Finding out when symbiosis began has been difficult because dinoflagellates have no hard or bony parts that fossilize. Instead, the researchers looked for three types of signatures in the coral fossils that indicate the past presence of algae: fossil microstructures, levels of different types of carbon and oxygen, and levels of two forms of nitrogen. First author Katarzyna Frankowiak of the Institute of Paleobiology at the Polish Academy of Sciences conducted the microstructural analysis with assistance from Marcelo Kitahara of the Federal University of Sao Paulo in Brazil, Maciej Mazur of the University of Warsaw, and Anders Meibom of the Ecole Polytechnique Federale de Lausanne and the Universite de Lausanne. Their analysis revealed regularly spaced patterns of growth consistent with the symbiotic corals' reliance on algal photosynthesis, which only takes place during daylight. Frankowiak and Anne Gothmann, who earned her Ph.D. from Princeton's Department of Geosciences in 2015 and is now a postdoctoral researcher at the University of Washington, measured the ratios of different types of oxygen and carbon and found that the results matched what would be expected when symbiosis occurs. The third approach, determining the forms of nitrogen -- which derive in part from the ammonium the corals had excreted -- was conducted by Xingchen (Tony) Wang, who earned his doctoral degree in geosciences from Princeton in 2016 and is now a postdoctoral research fellow working with Sigman. The nitrogen atoms, which are trapped in the fossil's calcium-carbonate matrix, come in two forms, or isotopes, that vary only by how many neutrons they have: 14N has seven neutrons while 15N has eight neutrons, making it slightly heavier. By studying modern corals, researchers knew that symbiotic corals contain a lower ratio of 15N to 14N compared to non-symbiotic corals. The team found that the fossilized corals also had a low 15N-to-14N ratio, indicating they were symbiotic. "Although algae were not present in the fossils, they left behind chemical signatures," Wang said. "We found strong evidence that the fossilized coral were symbiotic and that they lived in a nutrient-poor environment. We were able to link the environmental conditions from 200 million years ago to the evolution of corals." George Stanley, a professor of geosciences at the University of Montana, had earlier explored the question of when symbiosis first evolved in corals. "This confirms a hypothesis that my colleagues and I put forth 20 years ago," said Stanley, who is familiar with the research but had no role in it. "It is really exciting to see this confirmation." The fossils used in the study were collected in a mountainous region in Antalya, Turkey. During their lifetime, they lived in a shallow sunlit body of water called the Tethys Sea. Stanley said the work would not have been possible without the coral fossils, which were remarkably well-preserved. "These corals are such a wonderful resource because they are as if you picked them up off the beach yesterday, and this is because they were sealed in deposits for centuries." The fossil record also shows a significant reef expansion occurred around 205 million years ago, and this fits with a boost in coral growth due to the development of symbiosis, Stanley said.


News Article | May 18, 2016
Site: www.theguardian.com

Europe’s last primeval forest is facing what campaigners call its last stand as loggers prepare to start clear-cutting trees, following the dismissal of dozens of scientists and conservation experts opposed to the plan. Poland’s new far right government says logging is needed because more than 10% of spruce trees in the Unesco world heritage site of Białowieża are suffering from a bark beetle outbreak. But nearly half the logging will be of other species, according to its only published inventory. Oak trees as high as 150 feet that have grown for 450 years could be reduced to stumps under the planned threefold increase in tree fells. Białowieża hosts Europe’s largest bison population and wolves and lynx still roam freely across its sun-mottled interior. Its foliage stretches for nearly 1,000 square miles across the border between Poland and Belarus. Beneath its green canopy, sunlight filters down on to a panorama of skyscraper trees soaring as much as 180 feet into the air, swampy water pools dammed by beavers, and psychedelic fungi that sprout from tree trunks. But a recently-passed logging law to allow work to begin on the old-growth forest has divided families, and led to death threats against campaigners and allegations of an “environmental coup” by state interests linked to the timber trade. The logging in Białowieża is expected to raise about 700m złotys (£124m), and pave the way for extensive and more lucrative tree clearances. Sources say that internal government discussions have already begun on extending the new timber regime to the national park, which covers 17% of the forest and has been untouched by humans since the ice age. Mirosław Stepaniuk says he was sacked as director of Białowieża’s national park shortly after Polish elections six months ago because of his support for turning the whole forest into a protected conservation area. He told the Guardian: “An environmental coup is being staged here not just by the government, but by the national forestry authority. If they are successful, it could trigger a cascade, an avalanche of similar cases in other places.” Last week, another 32 members were dismissed from the state council for nature conservation, an advisory body which had opposed the logging plan and has been accused of “inefficiency”. “We were sacked because the new government needs scientists who will applaud increased logging, to convince public opinion that this insane idea is okay,” said Przemysław Chylarecki, one of the dismissed scientists. Most of the new council member are foresters, or colleagues of the environment minister, he added. Since taking office, the government has set up a new Scientific Council of Forestry but it may not be minded to challenge the logging plan. Its president, Prof Janusz Sowa, said in February: “There is [only] one method for managing forests: an axe.” The new Law and Justice party government is already in conflict with the EU over issues ranging from climate change policy to constitutional interference in the country’s courts and media, which is widely seen as undemocratic. Now, Brussels is weighing a separate court case over the law allowing 188,000 cubic metres of trees to be felled by 2021. The axe could fall on trees dotted around at least a quarter of the Białowieża forest area, excluding the national park, and possibly as much as two-thirds of it. Katarzyna Jagiełło, a spokeswoman for Greenpeace, told the Guardian: “The struggle to protect Białowieża and make it a national park is our Alamo. This place should be like our Serengeti or Great Barrier Reef. What happens to the forest here will define the future direction of nature conservation in our country.” Significantly, Greenpeace refuses to rule out direct action if the foresters move in. “Right now we are present in the forest,” Jagiełło said, “and whatever needs to be done to protect it, will be done.” With the logging law now passed, the battle for its future could begin at any time. The forest occupies a symbolic and almost mystical place in Poland’s national consciousness, and its fate stokes dangerous emotions, according to Joanna Łapińska, a 37-year-old librarian in a Białowieża group opposing the clearances. “Friends and families have fallen out over this,” she said. “When we were out petitioning recently, a sympathetic woman said ‘I can’t let you in because I don’t want a fight with my husband’.” “People connected with the foresters are very aggressive. They told us that we are eco-terrorists, paid by the Germans – it’s usually the Germans, Jews or Russians – and they even said that somebody should have killed some eco-activists.” At a conference organised by the national forestry authority in December, a former forester and beekeeper close to Jan Szyszko, the environment minister, received loud applause when he said that environmental experts “should be beheaded or put in jail for 25 years. They should be deported for what they did against the forest”. At the same meeting, Mikołaj Janowski, a councillor from Podlaskie, told environmentalists: “You are parasites. You get money for your incomprehensible, hostile scientific papers … You should be sent to Putin’s gulag for 10 years or more.” Revulsion against environmentalists has reached the highest levels of government. Earlier this year, the foreign minister, Witold Waszczykowski, told Bild newspaper: “We only want to cure our country of a few illnesses ... a new mixture of cultures and races, a world made up of cyclists and vegetarians, who only use renewable energy and who battle all signs of religion.” Sections of the Catholic and Orthodox churches have played a partisan role in the debate, with a passage from Genesis - “be fruitful, and multiply, replenish the earth and subdue it” - often used to justify increased logging. One orthodox priest from Hajnówka, Leonid Szeszko, recently called for scientific, environmental and NGOs which opposed the logging plans to be banned. Szyszko, who has championed the logging law, is a regular guest on the ultra-conservative Radio Maria, a Catholic radio station, and appears at conferences with a priest garbed in a forester’s green uniform. Foresters are revered in Poland as patriarchs, protectors and fire-providers and retain public support in surveys second only to police and fire officers. Critics say though, that the national forestry authority is a state-run monopoly which suffers a conflict of interests between its twin mandates to protect trees while maximising profits from logging. “It is a schizophrenic situation,” Stepaniuk said. “They are a regular profit-making company that deals in wood. They log and sell and make incredible money. If there was any pressure to increase their profits, they would not hesitate to sacrifice environmental protection, which they perceive as their least important duty.” More than 90% of the national forest authority’s annual 7bn złotys (£1.2bn) earnings come from the firewood, furniture and pulp trades. Little of it is seen by the communities from which the timber was logged, which draw greater revenues from eco-tourism. The forest’s 20,000 animal and plant species and Hansel and Gretel-style interior draw hordes of visitors every year, dazzled by its heterogeneous beauty and its clean reviving air. Tourism has helped to make Białowieża wealthier than many nearby villages but as its young people leave in search of better prospects, backing for the foresters among the elderly who remain is iron-clad, stoked by an anticipated bonanza of cheap fuel. Elżbieta Laprus, the president of Białowieża’s village council, said: “People who live here need firewood to heat their homes and [have] a good quality of life. They want to buy trees from here.” A five-year long bark beetle outbreak has infected up to 1 million of the forest’s spruce trees, and forestry officials are adamant that “active” forest management is now needed to save the rest. This includes the logging of trees that are more than 100 years old. Andrzej Antczak, the associate head forester in Hajnówka forest district, is a climate change agnostic, whose buildings are decorated with stuffed mink, deer and wild boar – a sign of the influence wielded by Poland’s hunting lobby which bridges the local community with politicians. Sitting in his forest office, he said: “The best method to control bark beetle outbreaks is to cut down affected trees and take them out of the forest. But we are prohibited from cutting trees which are older than 100 years, or in nature reserves, wet woodlands or peat bogs. More than 35% of our territory is protected and it is a very big problem.” Bark beetles outbreaks usually affect trees of more than 80 years old, and are associated with dry conditions and a drop in lowland water tables. Because spruce trees have flat root systems, they cannot soak up enough water to produce the quantities of resin they need to protect themselves. As the infestation spreads, the trees’ bark breaks off, further preventing water being circulated to its leaves. These turn brown and fall, before the tree finally dies. The beetle eruption is a cyclical phenomenon that began earlier this decade and may now be nearing its end, according to park scientists. But it is the second worst outbreak in the last century and experts fear it may be a sign of worse and more frequent diseases to come as climate change takes hold. Rafał Kowalczyk, the director of the Mammal Research Institute at the Polish Academy of Sciences, argues that as temperatures warm and precipitation falls, boreal trees such as pine and spruce will naturally retreat northwards. Nature should be allowed to take its course in the forest as it has always done, he says. Walking through a section of the woods hit hard by the outbreak, he snaps off a shard of decaying bark and exclaims: “Look at this dead spruce tree! It is probably more alive now than it ever was because so many creatures are now living on it. There are nearly 100 invertebrate species that it gives life to. Woodpeckers are searching the bark for larvae, and there is space for spiders and fungi. The tree is dead, but the forest is still alive and it will regenerate.” Kowalczyk points to a tree trunk several metres away, lying like a toppled sentry. It has three new tree saps growing from its decaying husk. Dead spruce create light in which seedlings best suited to the conditions can grow, he says. They also carve out space for predators such as lynx and wolves to hide, house themselves, and hunt. One is the predatory beetle, which feeds on bark beetles, according to Luc Bas, the director of the International Union for the Conservation of Nature’s European office, who argued that removing the dead wood would also remove the bark beetles’ nemesis. Chopping down infected trees would be ineffective because “to stop the beetle attack in a managed way, at least 80% of the spruce trees would have to be removed,” he wrote in April. “This simply is not possible because the wider region of Białowieża is divided in several interconnected zones, including large reserves and park areas that may not be touched.” The IUCN and Unesco, and many of the world’s environmental scientists, have thrown themselves into the debate with gusto. Last week, a letter sent to the Polish government by academics, including professors at Harvard and Oxford, said that the plan would destroy the forest’s ability to recover from the outbreak and mark a “drastic” break with international conservation rules. The academics wrote that the logging plan “is a drastic example of breaking [international conservation] rules. It will radically change the forest and will also impact the economic returns from tourism to the forest.” Any move to implement it would be “a very alarming and worrying sign for the international community.” Poland’s government and forestry authority counter that Białowieża is not a predominantly natural forest. Logging by Germans in the first world war, the Soviet Union in world war two and, particularly, the British Century European Timber Corporation, led to significant replanting in the forest, Antczak says. The very word “spruce” in English comes from the polish “s” (from) and “Prus” (Prussia). Białowieża’s “naturalness” has been interrupted by Polish kings and Lithuanian dukes who fed their armies on its animals, Russian tsars who turned the park into a hunting ground, and Nazi soldiers who executed and buried Jews and resistance fighters there. But mass tree felling and replanting in Białowieża did not begin until 1920 and trees of 100 years or older – 41% of Białowieża’s total forest outside the national park – have been naturally regenerating for millennia, even if their surrounding habitat is now mixed. Chylarecki said: “The animals need all of these valuable trees to survive. Lynx or bisons or three-toed woodpeckers will not survive long in national park and nature reserves alone. They need large forest tracts to roam in.” A compromise agreement with the previous government in 2012 allowed an increase in local logging 50% above estimated local needs. Local people say this was not enough. But spruce wood is resinous and does not burn well, so the firewood they need would have to come from other trees. “Everything the activists do they do against the local community,” Laprus said. “People who don’t live here want to change our lives without consulting us. If the European commission really wanted to help, they would help give us grants to change our heating from wood to gas.” For Kowalczyk though, logging would threaten the tourist trade which employs far more people than Białowieża’s 100 local foresters. “Tourists come here to see primeval forest which is wet and wild and dark,” he said. “They are afraid of the forest but it is magical. Managed forests, you can see everywhere.” As the sun goes down on Białowieża, a night chorus of frogs, nightingales and warblers pipes up under its clear and constellated skies. The forest is still thriving, despite the shadow of the axe.


News Article | February 24, 2017
Site: phys.org

An innovative fiber laser has been developed at the Laser Centre of the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) and the Faculty of Physics of the University of Warsaw. Using a simple solution, the Warsaw optical scientists have "forced" one of the types of optical fiber lasers to generate ultrashort, high-energy pulses. The new laser is devoid of any mechanically sensitive external parts, which seems to be especially interesting for future applications. The invention greatly expedites the processing of materials in industrial laser machines. "Fiber lasers can be built so that all the processes important for the generation and shaping of the ultrashort pulses takes place in the fiber itself. Such devices, without any external mechanically sensitive components, operate in a very stable manner, and are ideal for working in difficult conditions," says Dr. Yuriy Stepanenko (IPC PAS). Laser action in the fiber leads to the generation of a continuous light beam. The release of energy in the shortest possible pulses is, however, much more favourable, since it signifies a great increase of power. Pulses are generated in fiber lasers via a saturable absorber system. When the light intensity is low, the absorber blocks light; when it is high, the absorber lets it through. Since femtosecond pulses have greater intensity than a continuous beam, the parameters of the absorber can be adjusted so that it only admits pulses. "Up to now, graphene sheets, among others, have been used as the saturable absorbers, in a form of a thin layer deposited on the tip of the fiber. But the diameters of optical fibers are in the order of single microns. Even a little energy cramped in such a small cross-section has a significant density per unit area, affecting the lifetime of the materials. Therefore, if an attempt was made to increase the power of the femtosecond pulses, the graphene on the tip of the connector was destroyed. Other absorbers, such as carbon nanotubes, may also undergo degradation," explains Jan Szczepanek, a PhD student from the Faculty of Physics of the University of Warsaw. In order to generate higher energy femtosecond pulses in the optical fiber, the Warsaw physicists decided to improve saturable absorbers of a different type, via the clever use of optical phenomena such as nonlinear effects that cause a change in the refractive index of glass. Electric and magnetic fields of light usually oscillate in random, mutually perpendicular directions. When the fields oscillate all the time in the same plane, the wave is called linearly polarized. In classical optics, it is assumed that when such a wave passes through a medium, it experiences a constant refractive index, regardless of the light intensity. In nonlinear optics this is different: At a sufficiently high light intensity, the refractive index begins to increase slightly. A nonlinear artificial saturable absorber works as follows. At the input, the linearly polarized light is divided into a beam with a low intensity and a beam with a high intensity. The medium of the absorber can be chosen for both light beams to experience a slightly different refractive index in order for them to travel at slightly different (phase) velocities. As a result of the velocity difference, the plane of polarization starts to rotate. At the output of the absorber, there is a polarization filter that only lets through waves oscillating perpendicularly to the plane of polarization of the incoming light. When the laser is operating in continuous mode, the light in the beam is of a relatively low intensity, an optical path difference does not occur, the polarization does not change, and the output filter blocks the light. At a high enough intensity, typical for femtosecond pulses, the rotation of polarization causes the pulse to pass through the polarizer. For the saturable absorber with polarization rotation to work, the fibre must have different refractive indices in different directions (thus it has to be birefringent), and both indices should also be stable. The problem is that in ordinary optical fibers, birefringence occurs accidentally, e.g. due to stress caused by the touch of a finger. Lasers built in this manner are extremely sensitive to external factors. In turn, birefringence of the polarization preserving fibers is so large that the light propagates in only one direction, and the construction of artificial saturable absorbers becomes physically impossible. "Birefringent optical fibers retaining the polarization state of the entering light are already in production. We are the first to demonstrate how they can be used to construct a saturable absorber: We cut the optical fiber into segments of an appropriate length and then reconnect them, rotating each successive segment 90 degrees in relation to its predecessor," says Ph.D. student Szczepanek. "Rotation means that if in one segment a pulse with, shall we say, vertical polarization travels slowly, in the next, it will run faster and catch up with the second pulse, polarized perpendicularly. A simple procedure has therefore allowed us to eliminate the main obstacle to increasing the energy, that is, the great difference in velocities between pulses of different polarities, typical for all polarization preserving fibres," explains Dr. Stepanenko. The more rotated segments there are, the better the quality of the pulses generated in the fiber. In the laser built in the Warsaw laboratory, the saturable absorber consisted of a fiber with a length of approximately 3 m, divided into three segments, and a filtering polarizer. The potential number of rotated segments can be increased up to even a dozen or so. The new laser produces high-quality femtosecond pulses, and their energy can be up to 1000 times larger than typical for lasers with material absorbers. In comparison to the devices with artificial absorbers, the laser made by Warsaw scientists has a much simpler construction and therefore its reliability is significantly greater. Explore further: Small, inexpensive, and incredibly resilient: A new femtosecond laser for industry More information: Jan Szczepanek et al, Ultrafast laser mode-locked using nonlinear polarization evolution in polarization maintaining fibers, Optics Letters (2017). DOI: 10.1364/OL.42.000575


News Article | December 14, 2016
Site: www.eurekalert.org

Cancer treatment is still one of the most intractable challenge for medicine. There are several approaches to fight cancer, which include: surgery, radiation therapy, chemotherapy, immunotherapy, targeted therapy and hormone therapy. From all these treatment methods, chemotherapy seems to be the most widely used. Therefore, it is understandable that scientists are trying to discover new molecules which may be applied as effective chemotherapeutics. The researchers from Jan D?ugosz University in Cz?stochowa and Centre of Molecular and Macromolecular Studies, Polish Academy of Sciences reviewed the most significant achievements in the area of cancer treatment, published in 2014/2015. This review describes newly discovered anticancer molecules interacting with DNA or affecting cancer cell cycles. New cancer treatment strategies, which increase efficiency of chemotherapy or radiotherapy and new chemotherapeutic delivery systems have also been mentioned in the review. Multiplicity of the described compounds proves that cancer battle is still in progress. We constantly learn something new about cancer cells and hopefully we are getting closer to find effective cancer treatment. We know that molecules can interact with cancer DNA by inhibiting its synthesis, transcription or duplication. Chemotherapeutics are also able to affect tumor cell cycle by suppressing itsproliferation and angiogenesis, and also promoting its apoptosis. However, developing effective cancer treatment is, still, a demanding task because the number of cancer cell-types known to researchers constantly increases. In spite of all these odds, we hope that along with the development of science, people will win the race with still incurable cancers. For more information about the article, please visit http://benthamscience. Reference: Turek, M.; (2016). New Hopes in Cancer Battle - A Review of New Molecules and Treatment Strategies Med. Chem., DOI: 10.2174/1573406412666160502153700


News Article | November 30, 2016
Site: www.eurekalert.org

Everything is pointing towards success in unravelling the mysteries inherent in every human language, which for nearly 100 years have been an object of intrigue for mathematicians and linguists working on studies into statistics of literature. New analysis of the frequencies of word occurrence in the most famous works of literature, undertaken at the Institute of Nuclear Physics of the Polish Academy of Sciences in Krakow, have shown that our languages are structurally more complex and more exhaustive than they ever before seemed. It's been said that 80% of a person's success is achieved from only 20% of their efforts. That famous ratio holds up over a surprising number of domains. For example, it is apparent that in every language, whether spoken or written, that 80% of all statements are made up of merely 20% of the most common words. One possible reason is that when we talk to each other we want to convey as much content as possible with the least effort (among other factors). This phenomenon of dependency was one of the earliest of the series of power laws to be discovered, and is known as Zipf's law. It has turned out that it is not as trivial as it might seem at first glance. Scientists from the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN) in Krakow have established that certain puzzling features of Zipf's law, for decades a source of intrigue for those involved in the statistical analysis of literary texts, are a consequence of neglecting one of the basic components of language. "A year ago, with the help of detailed multiscale analysis we showed that the length of sentences in literature -- that is, the distance between the sentence-ending punctuation -- shows a very complex dependency of a multifractal nature, especially evident in the works of the genre known as stream of consciousness. It was an intriguing result that prompted us to look with greater attention to the role of other punctuation marks, especially in the context of Zipf's law. The results have provided us with a new way to look at not only the role of punctuation among languages, but even within the same language," says Prof. Stanislaw Drozdz (IFJ PAN, Cracow University of Technology). Charts showing Zipf's law for literary texts are created with the use of an uncomplicated procedure. Each word is counted per how often it occurs in the text. Those which occur most often are assigned to rank 1, the next are placed in rank 2, etc. (in richer texts the ranks can even exceed ten thousand, and exotic words usually appear far above rank 1,000). Zipf's law states that the probability of a word is inversely proportional to its rank: the larger the rank, the lower the probability. Graphs showing the relationship are (on a logarithmic scale) on a straight line. Ever since the American linguist George Zipf popularized his law, it never ceases to amaze. How can something as complex as a structure created using language be described by such a straightforward law? There were more puzzles. Quite early on it was noticed that the graphs relating to the frequency of words for ranks closer to unity curve slightly downward from a straight line. That deviation particularly intrigued Benoit Mandelbrot, the great French mathematician of Polish origin, who worked on this issue for many years. He even suggested his own amendment to Zipf's original law, to better map deviation (it is worth mentioning at this point, that his work on Zipf's law, among other interests, helped guide him toward the concept of fractals). In this latest study, the physicists at IFJ PAN analyzed texts written in six Indo-European languages, two of each belonging to these groups: Germanic (English and German), Romance (French and Italian) and Slavic (Polish and Russian). The selected literary works come from the archives of Project Gutenberg , and each is at least five thousand sentences long. For each of the languages at least five different texts were chosen, and merged to form one text totaling about a million words. All words unrelated to the transmitted content were removed, such as 'chapter', 'part' and 'epilogue', and for all language-specific abbreviations like 'Mr.' and 'Dr.' the dots were removed and they were treated as separate words. Also deleted were annotations and footnotes, page numbers, and punctuation marks of a more typographical nature: quotation marks and parentheses. "The eventual punctuation marks considered for analysis were commas, colons, and semicolons, and those which end sentences: periods, exclamation marks, question marks, and ellipses," specifies Prof. Jaroslaw Kwapien (IFJ PAN), one of the co-authors of the scientific paper published in the renowned journal Information Sciences. Among the studied works of literature are: 1984 by George Orwell, Moby Dick by Herman Melville, Ulysses by James Joyce, Gulliver's Travels by Jonathan Swift, Gone with the Wind by Margaret Mitchell, Thus Spake Zarathustra by Friedrich Nietzsche, The Trial by Franz Kafka, The Magic Mountain by Thomas Mann, Madame Bovary by Gustave Flaubert, The Phantom of the Opera by Gaston Leroux, Foucault's Pendulum by Umberto Eco, Giacinta by Luigi Capuana, The Spring to Come by Stefan Zeromski, The Promised Land by Wladyslaw Reymont, The Doll by Boleslaw Prus, Anna Karenina and War and Peace by Leo Tolstoy, and The Brothers Karamazov by Fyodor Dostoevsky. Including punctuation marks led a to highly significant result: the downward bend seen on the original Zipf's graph for ranks close to unity practically disappears. The 'new words' (the punctuation marks) fall into place almost exactly so that together with the 'real words' the rank-frequency distribution now fits into the straight line for all ranks, thus extending the original form of Zipf's law to all the scales. Mandelbrot's amendment turned out to be generally redundant. "When we begin to treat punctuation marks like they are words they start occupying ranks closer to unity and with frequency relative to the ordinary words, so that the original Zipf departure from the straight line for small ranks basically disappears. Thus, upon considering punctuation, our language emerges as a more consistent composition! That's why it seems well-founded to say that punctuation is just as important to a language as its words, and language without it is basically incomplete," says Prof. Drozdz. New graphs reveal several novel and significant features. For example, considering punctuation in Slavic languages the thus generalized Zipf rank-frequency distribution falls almost perfectly along one line for all ranks. Some trace of the original Zipf's deviation remains for Romance and Germanic languages, and this is especially apparent with the English language. "What if while analyzing non-Slavic languages we didn't consider their additional specific features?" wonders Prof. Drozdz, being mindful of other interesting interpretations: "Might it also be that the cause of incomplete reduction of curvature is rooted in the language itself? For instance, in English there might be a source of easily discernable tendencies of authors to limit the number of punctuation marks. If this last cause holds true, it might be worth asking the question: can we be sure that excessive reduction of punctuation is a beneficial action that doesn't harm the integrity of the language?" The latest discovery from the IFJ PAN could potentially have implications beyond linguistic research. Zipfian deviation for ranks closer to unity is being observed in many areas and has diverse origins, which are often not fully understood. In the graphs prepared based on literary works the deviation disappears after accounting for the common factor, but so far this has been considered negligible. Perhaps in other cases it could also be eliminated by including elements which have thus far been deprived of a greater role. The Henryk Niewodniczanski Institute of Nuclear Physics (IFJ PAN) is currently the largest research institute of the Polish Academy of Sciences. The broad range of studies and activities of IFJ PAN includes basic and applied research, ranging from particle physics and astrophysics, through hadron physics, high-, medium-, and low-energy nuclear physics, condensed matter physics (including materials engineering), to various applications of methods of nuclear physics in interdisciplinary research, covering medical physics, dosimetry, radiation and environmental biology, environmental protection, and other related disciplines. The average yearly yield of the IFJ PAN encompasses more than 450 scientific papers in the Journal Citation Reports published by the Thomson Reuters. The part of the Institute is the Cyclotron Centre Bronowice (CCB) which is an infrastructure, unique in Central Europe, to serve as a clinical and research centre in the area of medical and nuclear physics. IFJ PAN is a member of the Marian Smoluchowski Krakow Research Consortium: "Matter-Energy-Future" which possesses the status of a Leading National Research Centre (KNOW) in physics for the years 2012-2017. The Institute is of A+ Category (leading level in Poland) in the field of sciences and engineering. Prof. Stanislaw Drozdz The Institute of Nuclear Physics of the Polish Academy of Sciences tel. 48-12-6628220 email: stanislaw.drozdz@ifj.edu.pl "In narrative texts punctuation marks obey the same statistics as words"; A. Kulig, J. Kwapien, T. Stanisz, S. Drozdz; Information Sciences 375 (2017) 98-113; DOI: http://dx. The website of the Institute of Nuclear Physics of the Polish Academy of Sciences. Press releases of the Institute of Nuclear Physics of the Polish Academy of Sciences.


News Article | February 23, 2017
Site: www.eurekalert.org

Pulse lasers built entirely on optical fibers are increasingly readily being used by industry. Optical scientists from the Warsaw Laser Centre of the Institute of Physical Chemistry of the Polish Academy of Sciences and the Faculty of Physics of the University of Warsaw have generated ultrashort laser pulses in an optical fiber, by using a method previously considered as physically impossible to achieve. Their solution is not only useful, but also surprisingly simple! An innovative fiber laser has come into being at the Laser Centre of the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) and the Faculty of Physics of the University of Warsaw. Using an ingenious and easy-to-implement solution, the Warsaw optical scientists have "forced" one of the types of optical fiber lasers to generate ultrashort high energy pulses. The method they used is particularly interesting because of the fact that it was considered by experts as impossible to achieve. The new laser is devoid of any mechanically sensitive external parts, what seems to be especially interesting for future applications. The patent-pending invention should soon greatly shorten the time of processing materials in industrial laser machines. "Fiber lasers can be built so that all the processes important for the generation and shaping of the ultrashort pulses take place in the fiber itself. Such devices, without any external mechanically sensitive components, operate in a very stable manner and are ideal for working in difficult conditions," says Dr. Yuriy Stepanenko (IPC PAS). Laser action in the fiber leads to the generation of a continuous light beam. The release of energy in the shortest possible pulses is however much more favourable since it signifies a great increase of power. Pulses are generated in fiber lasers by a system known as a saturable absorber. When the light intensity is low, the absorber blocks light, when it is high - it lets it through. Since in femtosecond pulses (i.e. those lasting millionths of a billionth of a second) the light intensity is much greater than in a continuous beam, the parameters of the absorber can be adjusted so that it only lets through pulses. "Up to now, graphene sheets, among others, have been used as the saturable absorbers, in a form of a thin layer deposited on the tip of the fiber. But the diameters of optical fibers are in the order of single microns. Even a little energy cramped in such a small cross-section has a significant density per unit area, affecting the lifetime of the materials. Therefore, if an attempt was made to increase the power of the femtosecond pulses, the graphene on the tip of the connector was destroyed. Other absorbers, such as carbon nanotubes, may also undergo degradation," explains Jan Szczepanek, a PhD student from the Faculty of Physics of the University of Warsaw, and the first author of the publication in the journal Optics Letters. In order to generate higher energy femtosecond pulses in the optical fiber, the Warsaw physicists decided to improve saturable absorbers of a different type, not functioning due to the unique properties of materials, but due to the clever use of optical phenomena, such as nonlinear effects causing a change in the refractive index of glass. Light is an electromagnetic wave, whose electric and magnetic fields usually oscillate in random, mutually perpendicular directions. When the fields oscillate all the time in the same plane, the wave is called linearly polarized. In classical optics, it is assumed that when such a wave passes through a medium it experiences a constant refractive index, regardless of the light intensity. In nonlinear optics this is different: at a sufficiently high light intensity the refractive index begins to increase slightly, the more so, the higher the intensity. A nonlinear artificial saturable absorber works as follows. At the input the linearly polarized light is divided into a beam with a low intensity and a beam with a high intensity. The medium of the absorber can be chosen for both light beams to experience a slightly different refractive index, that is, for them to travel at slightly different (phase) velocities. As a result of the velocity difference the plane of polarization starts to rotate. At the output of the absorber there is a polarization filter which only lets through waves oscillating perpendicularly to the plane of polarization of the incoming light. When the laser is operating in continuous mode, the light in the beam is of a relatively low intensity, an optical path difference does not occur, the polarization does not change and the output filter blocks the light. At a high enough intensity, typical for femtosecond pulses, the rotation of polarization causes the pulse to pass through the polarizer. For the saturable absorber with polarization rotation to work, the fibre not only must have different refractive indices in different directions (thus it has to be birefringent), but both indices should also be stable. The problem is that in ordinary optical fibers birefringence occurs accidentally, e.g. due to stress caused by the touch of a finger. Lasers built in this manner are extremely sensitive to external factors. In turn, birefringence of the polarization preserving fibers is so large that the light propagates in them in only one direction and the construction of artificial saturable absorbers becomes physically impossible. "Birefringent optical fibers retaining the polarization state of the light entering them are already in production in the world. We are the first to demonstrate how they can be used to construct a saturable absorber: we cut the optical fiber into segments of an appropriate length and then reconnect them, rotating each successive segment 90 degrees in relation to its predecessor," says PhD student Szczepanek. "Rotation means that if in one segment a pulse with, shall we say, vertical polarization travels slowly, in the next it will run faster and catch up with the second pulse, polarized perpendicularly. A simple procedure has therefore allowed us to eliminate the main obstacle on the road to increasing the energy, that is, the great difference in velocities between pulses of different polarities, so typical for all polarization preserving fibres," explains Dr. Stepanenko. The more rotated segments there are, the better the quality of the pulses generated in the fiber. In the laser built in the Warsaw laboratory the saturable absorber consisted of a fiber with a length of approx. 3 m, divided into 3 segments, and a filtering polarizer. The potential number of rotated segments can be increased up to even a dozen or so. The new laser produces high quality femtosecond pulses, and their energy can be up to 1000 times larger than typical for lasers with material absorbers. In comparison to the devices with artificial absorbers, the laser made by Warsaw scientists has a much simpler construction and therefore its reliability is significantly greater. The Institute of Physical Chemistry of the Polish Academy of Sciences was established in 1955 as one of the first chemical institutes of the PAS. The Institute's scientific profile is strongly related to the newest global trends in the development of physical chemistry and chemical physics. Scientific research is conducted in nine scientific departments. CHEMIPAN R&D Laboratories, operating as part of the Institute, implement, produce and commercialise specialist chemicals to be used, in particular, in agriculture and pharmaceutical industry. The Institute publishes approximately 200 original research papers annually.


News Article | February 22, 2017
Site: www.eurekalert.org

Cracow, 22 February 2017 The world around us is mainly constructed of baryons, particles composed of three quarks. Why are there no antibaryons, since just after the Big Bang, matter and antimatter came into being in exactly the same amounts? A lot points to the fact that after many decades of research, physicists are closer to the answer to this question. In the Large Hadron Collider beauty (LHCb) experiment the first trace of the differences between baryons and antibaryons has just been encountered. In data collected during the first phase of operation of the Large Hadron Collider the LHCb collaboration team has discovered an interesting asymmetry. The most recent analysis of decays of the beauty baryon Lambda b, a particle six times more massive than a proton, suggests that it decays a little differently than its antimatter counterpart. If this result is confirmed, it will be possible to talk about having observed the first difference between antibaryons and baryons, i.e. the family of particles which to a greater degree make up our everyday world. Certain differences between matter and antimatter have already been observed previously. In 1964, it was noticed that kaons - that is, K mesons, particles made up of a strange quark and an up or down antiquark - sometimes decay somewhat differently than antikaons (the Nobel Prize was awarded for this discovery in 1980). In turn, in recent years there have been reports of the discovery of slightly clearer differences in the decays of antimesons and B mesons of various types (the B meson consists of a beauty quark and an up, down, strange or charm quark). Mesons are quark-antiquark pairs with short lifetimes, appearing today in the Universe in small quantities, and on Earth, produced mainly in high-energy collisions in particle accelerators. Meanwhile the matter of which the macroscopic structures of our world are composed is made up of leptons (these include electrons) and to a greater degree baryons - clusters of three quarks (the proton is a baryon containing two up quarks and one down, as is the neutron which is composed of two down quarks and one up). The most recent analysis of data from the LHCb collaboration, published in the journal Nature Physics and concerning the decays of Lambda b particles composed of down, up and beauty quarks, is thus the first indication of the possible differences between baryonic matter and its antimatter reflection. "We cannot yet talk about a discovery. Nevertheless, we are dealing with something that seems to be an increasingly promising observational clue, taken from the data from the first stage of operation of the LHC accelerator. We will, however, have to wait for the final confirmation - or denial... - of the current result another dozen or so months until the official end of the analysis of data from the second run," stresses Prof. Marcin Kucharczyk from the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN) in Cracow, one of the participants of the LHCb collaboration. Modern particle physics and cosmological models suggest that antimatter came into being in exactly the same amounts as matter. This fact is linked with spectacular consequences: When a particle encounters its antiparticle, there is a great likelihood of mutual annihilation, i.e. a process in which both particles completely transform into energy. This mechanism is extremely efficient. The amount of energy generated by the annihilation of a kilogram of antimatter with a good approximation corresponds to the amount of energy that would be released as a result of burning the annual petrol production of all the refineries in Poland. If in the contemporary Universe there were planets, stars or galaxies made of antimatter, they should emit large amounts of radiation with very characteristic energies. This would arise due to the inevitable interactions with matter of the opposite type, leading to annihilation. Meanwhile, astronomers only observe annihilation radiation here and there and in residual amounts, well explained by physical phenomena which are also today responsible for the formation of small amounts of antimatter. Thus the fundamentally important question arises: since originally matter and antimatter filled the Universe in exactly equal amounts, why have they not completely disappeared? Why has a small portion of matter managed to survive the era of annihilation? In the living world great extinctions leading to the extinction of species last for tens and hundreds of thousands of years. Meanwhile, everything points to the fact that antimatter annihilated by matter disappeared from our universe fractions of a second after the Big Bang. For every few billion particles of matter just one particle survived the giant cataclysm. If a similar scale of destruction touched the human species, within seconds the Earth's population would be down to one live individual. The question of why only he survived would certainly be most apt. "In modern physics, it is assumed that the existence of matter should be due to some minor differences between the properties of particles and antiparticles. In equations, to convert a particle into an antiparticle, you have to change the sign of the corresponding quantum characteristics - in the case of electrons or the quarks making up protons or neutrons it is the electrical charge - and change the character of the spatial coordinates, i.e. form a mirror image. The combination of these two operations is called CP symmetry, that is, charge and parity symmetry. Thus, attempts to detect differences between matter and antimatter boil down to tracking events in which CP symmetry is not preserved," explains Prof. Kucharczyk. Looking for signs of CP violation, the LHCb collaboration researchers chose from a huge number of collisions and the products of their decays approx. 6,000 cases in which Lambda b particles decayed to a proton and three pi mesons (pions), and approx. 1,000 cases with a decay path leading to a proton, a pion and two kaons. Detailed analysis revealed that the angles at which the products of decays diverge are sometimes somewhat different for Lambda b baryons than for their antimatter partners. The result is confirmed with a statistical significance of 3.3 standard deviations (sigma), which corresponds to a probability of approx. 99% that it is not a random fluctuation. In particle physics it is assumed, however, that one can talk of a discovery only with a statistical significance of over 5 sigma, that is, when the probability of a random fluctuation is less than one to more than three million. The Henryk Niewodniczanski Institute of Nuclear Physics (IFJ PAN) is currently the largest research institute of the Polish Academy of Sciences. The broad range of studies and activities of IFJ PAN includes basic and applied research, ranging from particle physics and astrophysics, through hadron physics, high-, medium-, and low-energy nuclear physics, condensed matter physics (including materials engineering), to various applications of methods of nuclear physics in interdisciplinary research, covering medical physics, dosimetry, radiation and environmental biology, environmental protection, and other related disciplines. The average yearly yield of the IFJ PAN encompasses more than 500 scientific papers in the Journal Citation Reports published by the Thomson Reuters. The part of the Institute is the Cyclotron Centre Bronowice (CCB) which is an infrastructure, unique in Central Europe, to serve as a clinical and research centre in the area of medical and nuclear physics. IFJ PAN is a member of the Marian Smoluchowski Krakow Research Consortium: "Matter-Energy-Future" which possesses the status of a Leading National Research Centre (KNOW) in physics for the years 2012-2017. The Institute is of A+ Category (leading level in Poland) in the field of sciences and engineering. Prof. Marcin Kucharczyk The Institute of Nuclear Physics of the Polish Academy of Sciences tel. +48 12 6628050 email: marcin.kucharczyk@ifj.edu.pl http://www. The website of the Institute of Nuclear Physics of the Polish Academy of Sciences. http://press. Press releases of the Institute of Nuclear Physics of the Polish Academy of Sciences. IFJ170222b_fot01s.jpg HR: http://press. The first trace of differences between matter and "common", baryonic antimatter has just been encountered in decays of the beauty baryon Lambda b. Pictured above: LHCb Collaboration in front of LHCb detector. (Source: CERN, The LHCb Collaboration)


News Article | November 27, 2015
Site: www.nanotech-now.com

Abstract: Iron oxides occur in nature in many forms, often significantly different from each other in terms of structure and physical properties. However, a new variety of iron oxide, recently created and tested by scientists in Cracow, surprised both physicists and engineers, as it revealed features previously unobserved in any other material. The new form of iron oxide (FeO) is a metallic crystal with virtually no defects, a unique conglomerate of electrical and magnetic characteristics, and atoms that vibrate as if the number of dimensions has been reduced. This remarkable material has been prepared, modelled and tested by physicists at the Leading National Research Centre (KNOW) in Cracow, Poland, which includes, among others, the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ PAN), the Institute of Catalysis and Surface Chemistry of the PAS (IKiFP PAN) and the Faculty of Physics and Applied Computer Science of the University of Science and Technology (WFiIS AGH). A group at IFJ PAN was responsible for computer simulations of material. The team from IKiFP PAN and WFiIS AGH, who initiated the research, carried out experiments determining the formation of new iron oxide layers and its properties. Physicists at the European Synchrotron Radiation Facility (ESRF) in Grenoble, the University of the Sorbonne in Paris, and the Pedagogical University of Cracow also participated in the work. "We've been working with modelling materials, including varieties of iron oxide, for years. Our models, constructed on the basis of the fundamental principles of quantum mechanics and statistical physics, have allowed us to determine the positions of atoms in the crystal lattice and to predict the electric, magnetic and thermodynamic properties of materials," explains Dr. Przemyslaw Piekarz, head of Computational Materials Science at IFJ PAN. The theorists in Cracow specialize in studying lattice dynamics, allowing them to determine how atoms in a crystal of a material vibrate. One of the basic tools they use is the PHONON program, created and developed by Prof. Krzysztof Parlinski (IFJ PAN). The VASP (Vienna Ab-initio Simulation Package) software was used to optimize the model. "Our model contains a layer of oxygen and iron with the thickness of a single atom deposited on a substrate made of platinum. The atoms in the monolayer are arranged in a hexagonal structure, like a honeycomb, a construction similar to the famous hexagonal two-dimensional graphene layers," describes Dr. Piekarz. He stresses that graphene creates a perfectly flat surface, entirely composed of carbon atoms. The modeled iron oxide layer, however turns out to be crimped: each iron atom was here surrounded by three oxygen atoms, located a little further from the substrate than the iron was. Calculations carried out for a single monolayer have established what types of vibrations are performed by atoms in the crystal lattice at different energies. The theoretical predictions were verified against the measurements thanks to a group headed by Prof. Jozef Korecki (IKiFP PAN and AGH). Not only have they developed a procedure for the preparation of samples with multiple monolayers of iron oxide on a platinum substrate, but over the past few years they have also been carrying out a series of measurements of their properties using the ESRF synchrotron in Grenoble. "In our laboratory the key to stabilizing materials of unnatural origin is the deposition of monocrystalline layers on the substrate - in this case it was properly oriented single-crystal platinum - which enforces the structure of the growing medium layer. In the laboratories scientists managed to produce a structure of stoichiometric FeO numbering no more than two monolayers of the oxide. Upon adding successive layers, the whole automatically transformed into magnetite Fe3O4. We were able to choose the parameters of the process so that the structure of FeO remained stable for a thickness of several atomic layers," says Prof. Korecki. Experiments at the synchrotron in Grenoble revealed that measurement data concerning vibrations of atoms in the crystal lattice of the new form of iron oxide perfectly agree with the theoretical model. Analysis of the results for samples with varying numbers of layers did more than just confirm the accuracy of the theoretical description. Iron oxide usually forms crystal lattices in which atoms are arranged at the corners of a cube (this is the structure of wustite, and among other substances, table salt). It was expected that after applying successive layers of FeO such a cubic structure would emerge automatically. But analysis of vibrations of atoms in the crystal lattice of the samples showed that the systems that count up to around a dozen monolayers still retain the hexagonal structure. This means that the researchers from Cracow were able to produce a new variety of iron oxide, different from the existing crystal structures. Subsequent measurements showed that for the monolayers number from six to ten, the iron atoms in the crystal have a long-range magnetic order. This is an unusual feature since a basic version of iron oxide is an antiferromagnet, wherein the magnetic moments of iron atoms at different locations are oriented in opposite directions, and therefore the substance as a whole is not magnetized. Meanwhile, the magnetic properties of a new phase of FeO are visible even at room temperature. "Spintronic materials for construction equipment have been sought after for many years. These instruments make use not only of the electrical current, but also the conduction of electron spin, which is responsible for its magnetic properties," relates Dr. Piekarz. "Our new material is not an insulator, like most oxides, but metal. So this combination of electrical and magnetic properties, rare for oxides, may be interesting for spintronics, as well as in the construction of various types of sensors and detectors." Of particular interest, however, was the analysis of the vibration of atoms depending on the number of layers of FeO on the platinum substrate. For one or two layers the movement of atoms is of a two-dimensional nature. When the number of layers reaches six or more, atoms vibrate as in a typical three-dimensional crystal. In the materials studied to date the nature of the vibration was closely associated with the dimensionality of the system. Meanwhile, a new variant of iron oxide at three, four and five layers of atoms proved to vibrate in an intermediate manner, corresponding to the fractional numbers of dimensions. "We're dealing with the first material in which the nature of vibration of atoms gradually passes from two-dimensional to three-dimensional. A similar effect, although expected in theory, has never before been observed in any other substance," claims Dr. Piekarz. Research on a new form of iron oxide, funded by grants from the Polish National Science Centre, are described in the renowned journal Physical Review Letters. About The Henryk Niewodniczanski Institute of Nuclear Physics The Henryk Niewodniczanski Institute of Nuclear Physics (IFJ PAN) is currently the largest research institute of the Polish Academy of Sciences. The broad range of studies and activities of IFJ PAN includes basic and applied research, ranging from particle physics and astrophysics, through hadron physics, high-, medium-, and low-energy nuclear physics, condensed matter physics (including materials engineering), to various applications of methods of nuclear physics in interdisciplinary research, covering medical physics, dosimetry, radiation and environmental biology, environmental protection, and other related disciplines. The average yearly yield of the IFJ PAN encompasses more than 450 scientific papers in the Journal Citation Reports published by the Thomson Reuters. The part of the Institute is the Cyclotron Centre Bronowice (CCB) which is an infrastructure, unique in Central Europe, to serve as a clinical and research centre in the area of medical and nuclear physics. IFJ PAN is a member of the Marian Smoluchowski Krakow Research Consortium: "Matter-Energy-Future" which possesses the status of a Leading National Research Centre (KNOW) in physics for the years 2012-2017. The Institute is of A+ Category (leading level in Poland) in the field of sciences and engineering. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


News Article | November 30, 2016
Site: www.eurekalert.org

John Friedlander of the University of Toronto and Henryk Iwaniec of Rutgers University will receive the 2017 AMS Joseph L. Doob Prize. The two are honored for their book Opera de Cribro (AMS, 2010). The prime numbers, the building blocks of the whole numbers, have fascinated humankind for millennia. While it has been known since the time of Euclid that the number of primes is infinite, exactly how they are distributed among the whole numbers is still not understood. The Latin title of the prizewinning book by Friedlander and Iwaniec could be translated as A Laborious Work Around the Sieve, where in this context a "sieve" is a mathematical tool for sifting prime numbers out of sets of whole numbers. The Sieve of Eratosthenes, dating from the third century BC, is a simple, efficient method to produce a table of prime numbers. For a long time, it was the only way to study the mysterious sequence of the primes. In the early 20th century, improvements came through the work of Norwegian mathematician Viggo Brun, who combined the Sieve of Eratosthenes with ideas from combinatorics. Tools from another branch of mathematics, complex analysis, came into play through the work of English mathematicians G.H. Hardy and J.E. Littlewood, and of the iconic Indian mathematician Srinivasa Ramanujan (protagonist of the 2016 film The Man Who Knew Infinity). For 30 years, Brun's method and its refinements were the main tools in sieve theory. Then, in 1950, another Norwegian mathematician, Atle Selberg, put forward a new, simple, and elegant method. As his method was independent of that of Brun, the combination of the two gave rise to deep new results. The latter part of the 20th century saw the proof of many profound results on classical prime-number questions that had previously been considered inaccessible. Among these was a formula for the number of primes representable as the sum of a square and of a fourth power, obtained by Friedlander and Iwaniec in 1998. With these developments, the time was ripe for a new book dealing with prime-number sieves and the techniques needed for their applications. Written by two of the top masters of the subject, Opera de Cribro is an insightful and comprehensive presentation of the theory and application of sieves. In addition to providing the latest technical background and results, the book looks to the future by raising new questions, giving partial answers, and indicating new ways of approaching the problems. With high-quality writing, clear explanations, and numerous examples, the book helps readers understand the subject in depth. "These features distinguish this unique monograph from anything that had been written before on the subject and lift it to the level of a true masterpiece," the prize citation says. The two prizewinners collaborated on an expository article on number sieves, "What is the Parity Phenomenon?", which appeared in the August 2009 issue of the AMS Notices. Born in Toronto, John Friedlander received his BSc from the University of Toronto and his MA from the University of Waterloo. In 1972, he earned his PhD at Pennsylvania State University under the supervision of S. Chowla. His first position was that of assistant to Atle Selberg at the Institute for Advanced Study. After further positions at IAS, the Massachusetts Institute of Technology, the Scuola Normale Superiore in Pisa, and the University of Illinois at Urbana-Champaign, he returned to the University of Toronto as a faculty member in 1980. He was Mathematics Department Chair from 1987 to 1991 and since 2002 has been University Professor of Mathematics. He was awarded the Jeffery-Williams Prize of the Canadian Mathematical Society (1999) and the CRM-Fields (currently CRM-Fields-PIMS) Prize of the Canadian Mathematical Institutes (2002). He gave an invited lecture at the International Congress of Mathematicians in Zurich in 1994. He is a Fellow of the Royal Society of Canada, a Founding Fellow of the Fields Institute, and a Fellow of the AMS. Born in Elblag, Poland, Henryk Iwaniec graduated from Warsaw University in 1971 and received his PhD in 1972. In 1976 he defended his habilitation thesis at the Institute of Mathematics of the Polish Academy of Sciences and was elected to member correspondent. He left Poland in 1983 to take visiting positions in the USA, including long stays at the Institute for Advanced Study in Princeton. In 1987, he was appointed to his present position as New Jersey State Professor of Mathematics at Rutgers University. He was elected to the American Academy of Arts and Sciences (1995), the US National Academy of Sciences (2006), and the Polska Akademia Umiejetnosci (2006, foreign member). He has received numerous prizes including the Sierpinski Medal (1996), the Ostrowski Prize (2001, shared with Richard Taylor and Peter Sarnak), the AMS Cole Prize in Number Theory (2002, shared with Richard Taylor), the AMS Steele Prize for Mathematical Exposition (2011), the Banach Medal of the Polish Academy of Sciences (2015), and the Shaw Prize in Mathematical Sciences (2015, shared with Gerd Faltings). He was an invited speaker at the International Congress of Mathematicians in Helsinki (1978), Berkeley (1986), and Madrid (2006). Presented every three years, the AMS Doob Prize recognizes a single, relatively recent, outstanding research book that makes a seminal contribution to the research literature, reflects the highest standards of research exposition, and promises to have a deep and long-term impact in its area. The prize will be awarded Thursday, January 5, 2017, at the Joint Mathematics Meetings in Atlanta. Find out more about AMS prizes and awards at http://www. . Founded in 1888 to further mathematical research and scholarship, today the American Mathematical Society fulfills its mission through programs and services that promote mathematical research and its uses, strengthen mathematical education, and foster awareness and appreciation of mathematics and its connections to other disciplines and to everyday life.


Gawronska-Kozak B.,Pennington Biomedical Research Center | Gawronska-Kozak B.,Polish Academy of Sciences
Matrix Biology | Year: 2011

Similar to mammalian fetuses FOXN1 deficient (nude) mice are able to restore the structure and integrity of injured skin in a scarless healing process by mechanisms independent of the genetic background. Matrix metalloproteinases (MMPs) are required for regular skin wound healing and the distinctive pattern of their expression has been implicated to promote scarless healing. In this study, we analyzed the temporal and spatial expression patterns of these molecules during the incisional skin wounds in adult nude mice. Macroscopic and histological analyses of skin wounds revealed an accelerated wound healing process, minimal granulation tissue formation and markedly diminished scarring in nude mice. Quantitative RT-PCR (Mmp-2, -3, -8, -9, -10, -12, -13, -14 and Timp-1, -2, -3), Western blots (MMP-13) and gelatin zymography (MMP-9) revealed that MMP-9 and MMP-13 showed a unique, bimodal pattern of up-regulation during the early and late phases of wound healing in nude mice. Immunohistochemically MMP-9 and MMP-13 were generally detected in epidermis during the early phase and in dermis during the late (remodeling) phase. Consistent with these in vivo observations, dermal fibroblasts cultured from nude mice expressed higher levels of types I and III collagen, MMP-9 and MMP-13 mRNA levels and higher MMP enzyme activity than wild type controls. Collectively, these finding suggest that the bimodal pattern of MMP-9 and MMP-13 expression during skin repair process in nude mice could be a major component of their ability for scarless healing. © 2011 International Society of Matrix Biology.


Garcia-Martin R.,Complutense University of Madrid | Kaminski R.,Polish Academy of Sciences | Pelaez J.R.,Complutense University of Madrid | De Elvira J.R.,Complutense University of Madrid
Physical Review Letters | Year: 2011

We use our latest dispersive analysis of ππ scattering data and the very recent Kℓ4 experimental results to obtain the mass, width, and couplings of the two lightest scalar-isoscalar resonances. These parameters are defined from their associated poles in the complex plane. The analytic continuation to the complex plane is made in a model-independent way by means of once- and twice-subtracted dispersion relations for the partial waves, without any other theoretical assumption. We find the f0(600) pole at (457-13+14)-i(279-7+11)MeV and that of the f0(980) at (996±7)-i(25-6+10)MeV, whereas their respective couplings to two pions are 3.59-0.13+0.11 and 2.3±0.2GeV. © 2011 American Physical Society.


Chatman S.,Pacific Northwest National Laboratory | Zarzycki P.,Polish Academy of Sciences | Rosso K.M.,Pacific Northwest National Laboratory
Physical Chemistry Chemical Physics | Year: 2013

Hematite (α-Fe2O3) is an important candidate electrode for energy system technologies such as photoelectrochemical water splitting. Conversion efficiency issues with this material are presently being addressed through nanostructuring, doping, and surface modification. However, key electrochemical properties of hematite/electrolyte interfaces remain poorly understood at a fundamental level, in particular those of crystallographically well-defined hematite faces likely present as interfacial components at the grain scale. We report a combined measurement and theory study that isolates and evaluates the equilibrium surface potentials of three nearly defect-free single crystal faces of hematite, titrated from pH 3 to 11.25. We link measured surface potentials with atomic-scale surface topology, namely the ratio and distributions of surface protonation-deprotonation site types expected from the bulk structure. The data reveal face-specific points of zero potential (PZP) relatable to points of zero net charge (PZC) that lie within a small pH window (8.35-8.85). Over the entire pH range the surface potentials show strong non-Nernstian charging at pH extremes separated by a wide central plateau in agreement with surface complexation modeling predictions, but with important face-specific distinctions. We introduce a new surface complexation model based on fitting the entire data set that depends primarily only on the proton affinities of two site types and the two associated electrical double layer capacitances. The data and model show that magnitudes of surface potential biases at the pH extremes are on the order of 100 mV, similar to the activation energy for electron hopping mobility. An energy band diagram for hematite crystallites with specific face expression and pH effects is proposed that could provide a baseline for understanding water splitting performance enhancement effects from nanostructuring, and guide morphology targets and pH for systematic improvements in efficiency. © 2013 The Owner Societies.


Misiorny M.,Jülich Research Center | Misiorny M.,Adam Mickiewicz University | Barnaa J.,Adam Mickiewicz University | Barnaa J.,Polish Academy of Sciences
Physical Review Letters | Year: 2013

Spin-polarized transport through bistable magnetic adatoms or single-molecule magnets (SMMs), which exhibit both uniaxial and transverse magnetic anisotropy, is considered theoretically. The main focus is on the impact of transverse anisotropy on transport characteristics and the adatom's or SMM's spin. In particular, we analyze the role of quantum tunneling of magnetization (QTM) in the mechanism of the current-induced spin switching, and show that the QTM phenomenon becomes revealed as resonant peaks in the average values of the molecule's spin and in the charge current. These features appear at some resonant fields and are observable when at least one of the electrodes is ferromagnetic. © 2013 American Physical Society.


Zarzycki P.,Polish Academy of Sciences | Kerisit S.,Pacific Northwest National Laboratory | Rosso K.M.,Pacific Northwest National Laboratory
Journal of Physical Chemistry C | Year: 2015

We present classical molecular simulations of the adsorption free energy profiles for the aqueous Fe(II) ion approaching key low index crystal faces of goethite at neutral surface charge conditions. Calculated profiles show minima corresponding to stable outer- and inner-sphere adsorbed structures. We analyzed the energetics and kinetics of most possible interfacial electron transfer reactions, as well as analyzing the same for subsurface migration pathways of injected electrons through calculating the Marcus free energy surfaces. We conclude that inner-sphere Fe(II)-complex formation is required for the interfacial electron transfer to occur, but the energetic cost of moving from the outer-sphere to inner-sphere geometry may prevent electron injection at some faces. We also show that some surfaces, especially (101), (100) and (001), are more energetically prone toward reduction than others. We demonstrate that subsurface charge migration in directions parallel to the surface, which run along the iron chains, is more energetically plausible than conduction through the resistive crystal bulk phase. Collectively this leads to the conclusion that Fe(II)-catalyzed recrystallization of goethite most likely proceeds by short path length electron migration through specific goethite surfaces along specific directions, until capture at Fe sites structurally susceptible to reduction and release. © 2015 American Chemical Society.


Madejski G.,Kavli Institute for Particle Astrophysics and Cosmology | Sikora M.,Polish Academy of Sciences
Annual Review of Astronomy and Astrophysics | Year: 2016

This article reviews the recent observational results regarding γ-ray emission from active galaxies. The most numerous discrete extragalactic γ-ray sources are AGNs dominated by relativistic jets pointing in our direction (commonly known as blazars), and they are the main subject of the review. They are detected in all observable energy bands and are highly variable. The advent of the sensitive γ-ray observations, afforded by the launch and continuing operation of the Fermi Gamma-ray Space Telescope and the AGILE Gamma-ray Imaging Detector, as well as by the deployment of current-generation Air Cerenkov Telescope arrays such as VERITAS, MAGIC, and HESS-II, continually provides sensitive γ-ray data over the energy range of ∼100 MeV to multi-TeV. Importantly, it has motivated simultaneous, monitoring observations in other bands, resulting in unprecedented time-resolved broadband spectral coverage. After an introduction, in Sections 3, 4, and 5, we cover the current status and highlights of γ-ray observations with (mainly) Fermi but also AGILE and put those in the context of broadband spectra in Section 6. We discuss the radiation processes operating in blazars in Section 7, and we discuss the content of their jets and the constraints on the location of the energy dissipation regions in, respectively, Sections 8 and 9. Section 10 covers the current ideas for particle acceleration processes in jets, and Section 11 discusses the coupling of the jet to the accretion disk in the host galaxy. Finally, Sections 12, 13, and 14 cover, respectively, the contribution of blazars to the diffuse γ-ray background, the utility of blazars to study the extragalactic background light, and the insight they provide for study of populations of supermassive black holes early in the history of the Universe. © 2016 by Annual Reviews.


The coupled high-resolution carbon isotope data from whole-rock limestone and organic matter samples of the transitans (Early Frasnian), punctata and the earliest hassi Zones (Middle Frasnian) from the South Polish carbonate shelf successions reveal the presence of a large, multi-part δ13C excursion, one of the largest known carbon cycle disturbance of Devonian period. This Early-Middle Frasnian (E-MF) δ13C perturbation consists of two positive excursions (a minor event I and a major event III) and two negative shifts (events II and IV). The major positive excursion, up to 5%, begins near the E-MF boundary and the onset of Middlesex transgressive-anoxic event. The latter broader-scale positive δ13C perturbation correlates with the worldwide punctata Event documented across eastern and western Laurussia as well as northern Gondwana. The large magnitude of the punctata Isotopic Event, paired with negligible biotic effects, is similar to the Silurian biogeochemical perturbations but contrasts markedly with the younger Kellwasser Events. The distinctive protracted (about 1Ma) E-MF δ13C variations may be only partly explained by escalated sea water exchange between epeiric seas and the anoxic open ocean during successive transgressive pulses. Very high δ13C plateau values of the punctata Event correspond to a positive 87Sr/86Sr shift, as well as elevated clastic input proxies and magnetic susceptibility, suggesting altogether that delivery of tectonically-promoted land-derived nutrients to marine basins was a key factor stimulating the biogeochemical perturbation. Extreme increases in primary productivity and enhanced organic matter burial in restricted deeper basinal settings would promote a gradual drawdown in surface-water as well as atmospheric pCO2, and consequently a climatic cooling by 5°C, as indicated by the high-resolution δ18Ophosphate record. © 2012 Elsevier B.V.


Herrera-Viedma E.,University of Granada | Cabrerizo F.J.,Spanish University for Distance Education (UNED) | Kacprzyk J.,Polish Academy of Sciences | Pedrycz W.,University of Alberta
Information Fusion | Year: 2014

In the consensus reaching processes developed in group decision making problems we need to measure the closeness among experts' opinions in order to obtain a consensus degree. As it is known, to achieve a full and unanimous consensus is often not reachable in practice. An alternative approach is to use softer consensus measures, which reflect better all possible partial agreements, guiding the consensus process until high agreement is achieved among individuals. Consensus models based on soft consensus measures have been widely used because these measures represent better the human perception of the essence of consensus. This paper presents an overview of consensus models based on soft consensus measures, showing the pioneering and prominent papers, the main existing approaches and the new trends and challenges. © 2013 Elsevier B.V. All rights reserved.


Bozek P.,AGH University of Science and Technology | Bozek P.,Polish Academy of Sciences | Bzdak A.,Brookhaven National Laboratory | Skokov V.,Western Michigan University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2014

We show that in proton-lead (p + Pb) collisions at the LHC, the Color Glass Condensate (CGC) and hydrodynamics lead to qualitatively different behavior of the average transverse momentum, 〈p⊥〉, with the particle rapidity. In hydrodynamics, the 〈p⊥〉 decreases as one goes from zero rapidity, y = 0, to the proton fragmentation region since the number of particles decreases. In contrast, in the CGC the saturation momentum increases as one goes from y = 0 to the proton fragmentation region, and so the 〈p⊥〉 increases. At the LHC, the difference between the two models may be large enough to be tested experimentally. © 2014 The Authors. Published by Elsevier B.V.


Pawela L.,Polish Academy of Sciences | Sladkowski J.,University of Silesia
Physica A: Statistical Mechanics and its Applications | Year: 2013

We study the possible advantages of adopting quantum strategies in multi-player evolutionary games. We base our study on the three-player Prisoner's Dilemma (PD) game. In order to model the simultaneous interaction between three agents we use hypergraphs and hypergraph networks. In particular, we study two types of networks: a random network and a SF-like network. The obtained results show that in the case of a three-player game on a hypergraph network, quantum strategies are not necessarily stochastically stable strategies. In some cases, the defection strategy can be as good as a quantum one. © 2012 Elsevier B.V. All rights reserved.


Gorzelak P.,Polish Academy of Sciences | Salamon M.A.,University of Silesia | Baumiller T.K.,University of Michigan
Proceedings of the National Academy of Sciences of the United States of America | Year: 2012

Sea urchins are a major component of recent marine communities where they exert a key role as grazers and benthic predators. However, their impact on past marine organisms, such as crinoids, is hard to infer in the fossil record. Analysis of bite mark frequencies on crinoid columnals and comprehensive genus-level diversity data provide unique insights into the importance of sea urchin predation through geologic time. These data show that over the Mesozoic, predation intensity on crinoids, as measured by bite mark frequencies on columnals, changed in step with diversity of sea urchins. Moreover, Mesozoic diversity changes in the predatory sea urchins show a positive correlation with diversity of motile crinoids and a negative correlation with diversity of sessile crinoids, consistent with a crinoid motility representing an effective escape strategy. We contend that the Mesozoic diversity history of crinoids likely represents a macroevolutionary response to changes in sea urchin predation pressure and that it may have set the stage for the recent pattern of crinoid diversity in which motile forms greatly predominate and sessile forms are restricted to deep-water refugia.


Bzdak A.,Brookhaven National Laboratory | Bozek P.,AGH University of Science and Technology | Bozek P.,Polish Academy of Sciences
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2013

We discuss various contributions to the event-by-event charge asymmetry dependence of π+ and π- elliptic flow, recently measured by the STAR Collaboration at RHIC. It is shown that under general assumptions, the difference between v2+ and v2- at a given fluctuating value of an asymmetry parameter, A, is a linear function of A, as observed in the preliminary data. We discuss two mechanisms that are qualitatively consistent with the experimental data and result in a signal of the correct order of magnitude. Our subsequent hydrodynamic calculations, assuming local charge conservation at freeze-out, yield a qualitative and partial quantitative understanding of the observed signal, so offering a detailed test of the hydrodynamic model in heavy-ion collisions. © 2013 Elsevier B.V.


Pawelaa L.,Polish Academy of Sciences | Sladkowski J.,University of Silesia
Physica D: Nonlinear Phenomena | Year: 2013

Coordination and cooperation are among the most important issues of game theory. Recently, the attention turned to game theory on graphs and social networks. Encouraged by interesting results obtained in quantum evolutionary game analysis, we study cooperative Parrondo's games in a quantum setup. The game is modeled using multidimensional quantum random walks with biased coins. We use the GHZ and W entangled states as the initial state of the coins. Our analysis shows that an apparent paradox in cooperative quantum games and some interesting phenomena can be observed. © 2013 Elsevier B.V.


Staato A.M.,Pennsylvania State University | Staato A.M.,Brookhaven National Laboratory | Staato A.M.,Polish Academy of Sciences | Xiao B.-W.,Central China Normal University | Zaslavsky D.,Pennsylvania State University
Physical Review Letters | Year: 2014

We present results from the first next-to-leading-order (NLO) numerical analysis of forward hadron production in pA and dA collisions in the small-x saturation formalism. Using parton distributions and fragmentation functions at NLO, as well as the dipole amplitude from the solution to the Balitsky-Kovchegov equation with running coupling, together with the NLO corrections to the hard coefficients, we obtain a good description of the available RHIC data in dAu collisions. In the large p⊥ region beyond the saturation scale, we find that the NLO correction becomes dominant and negative, which indicates that other physics beyond NLO becomes important and should also be taken into account. Furthermore, we make predictions for forward hadron production in pPb collisions at the LHC. This analysis not only incorporates the important NLO corrections for all partonic channels, but also reduces the renormalization scale dependence and helps to significantly reduce the theoretical uncertainties. It therefore provides a precise test of saturation physics beyond the leading logarithmic approximation. © 2014 American Physical Society.


Breuer M.,University College London | Zarzycki P.,Polish Academy of Sciences | Blumberger J.,University College London | Rosso K.M.,Pacific Northwest National Laboratory
Journal of the American Chemical Society | Year: 2012

Electron-transporting multi-heme cytochromes are essential to the metabolism of microbes that inhabit soils and carry out important biogeochemical processes. Recently the first crystal structure of a prototype bacterial deca-heme cytochrome (MtrF) has been resolved and its electrochemistry characterized. However, the molecular details of electron transport along heme chains in the cytochrome are difficult to access via experiment due to the nearly identical chemical nature of the heme cofactors. Here we employ large-scale molecular dynamics simulations to compute the redox potentials of the 10 hemes of MtrF in aqueous solution. We find that as a whole they fall within a range of ∼0.3 V, in agreement with experiment. Individual redox potentials give rise to a free energy profile for electron transport that is approximately symmetric with respect to the center of the protein. Our calculations indicate that there is no significant potential bias along the orthogonal octa- and tetra-heme chains, suggesting that under aqueous conditions MtrF is a nearly reversible two-dimensional conductor. © 2012 American Chemical Society.


Malecki P.H.,Polish Academy of Sciences | Raczynska J.E.,Polish Academy of Sciences | Raczynska J.E.,Southwestern Medical Center | Vorgias C.E.,National and Kapodistrian University of Athens | Rypniewski W.,Polish Academy of Sciences
Acta Crystallographica Section D: Biological Crystallography | Year: 2013

X-ray crystallography reveals chitinase from the psychrophilic bacterium Moritella marina to be an elongated molecule which in addition to the catalytic β/α-barrel domain contains two Ig-like domains and a chitin-binding domain, all linked in a chain. A ligand-binding study using NAG oligomers showed the enzyme to be active in the crystal lattice and resulted in complexes of the protein with oxazolinium ion (the reaction intermediate) and with NAG2, a reaction product. The characteristic motif DXDXE, containing three acidic amino-acid residues, which is a signature of type 18 chitinases, is conserved in the enzyme. Further analysis of the unliganded enzyme with the two protein-ligand complexes and a comparison with other known chitinases elucidated the roles of other conserved residues near the active site. Several features have been identified that are probably important for the reaction mechanism, substrate binding and the efficiency of the enzyme at low temperatures. The chitin-binding domain and the tryptophan patch on the catalytic domain provide general affinity for chitin, in addition to the affinity of the binding site; the two Ig-like domains give the protein a long reach over the chitin surface, and the flexible region between the chitin-binding domain and the adjacent Ig-like domain suggests an ability of the enzyme to probe the surface of the substrate, while the open shallow substrate-binding groove allows easy access to the active site. © 2013 International Union of Crystallography Printed in Singapore - all rights reserved.


Malina R.M.,University of Texas at Austin | Malina R.M.,Tarleton State University | Koziel S.M.,Polish Academy of Sciences
Journal of Sports Sciences | Year: 2014

This study attempted to validate an anthropometric equation for predicting age at peak height velocity (APHV) in 193 Polish boys followed longitudinally 8-18 years (1961-1972). Actual APHV was derived with Preece-Baines Model 1. Predicted APHV was estimated at each observation using chronological age (CA), stature, mass, sitting height and estimated leg length. Mean predicted APHV increased from 8 to 18 years. Actual APHV was underestimated at younger ages and overestimated at older ages. Mean differences between predicted and actual APHV were reasonably stable between 13 and 15 years. Predicted APHV underestimated actual APHV 3 years before, was almost identical with actual age 2 years before, and then overestimated actual age through 3 years after PHV. Predicted APHV did not differ among boys of contrasting maturity status 8-11 years, but diverged among groups 12-15 years. In conclusion, predicted APHV is influenced by CA and by early and late timing of actual PHV. Predicted APHV has applicability among average maturing boys 12-16 years in contrast to late and early maturing boys. Dependence upon age and individual differences in actual APHV limits utility of predicted APHV in research with male youth athletes and in talent programmes. © 2013 Taylor & Francis.


Grant
Agency: Cordis | Branch: FP7 | Program: CP | Phase: INFRA-2007-2.1-01 | Award Amount: 2.46M | Year: 2008

Key questions in particle and astroparticle physics can be answered only by construction of new giant underground observatories to search for rare events and to study sources of terrestrial and extra-terrestrial neutrinos. In this context, the European Astroparticle Roadmap of 03/07, via ApPEC and ASPERA, states: We recommend a new large European infrastructure, an international multi-purpose facility of 105-106 ton scale for improved studies of proton decay and low-energy neutrinos. Water-Cherenkov, Liq. Scintillator & Liq. Argon should be evaluated as a common design study together with the underground infrastructure and eventual detection of accelerator neutrino beams. This study should take into account worldwide efforts and converge by 2010... Furthermore, the latest particle physics roadmap from CERN of 11/06 states:A range of very important non-accelerator experiments takes place at the overlap of particle and astroparticle physics exploring otherwise inaccessible phenomena; Council will seek with ApPEC a coordinated strategy in these areas of mutual interest. Reacting to this, uniting scientists across Europe, we propose here a design study, LAGUNA, to produce by 2010 a full conceptual design sufficient to provide policy makers and funding agencies with enough information for a construction decision. Has Europe the technical and human capability to lead future underground science by hosting the next generation underground neutrino and rare event observatory? We aim to answer this question. Certainly construction will exceed the capacity of any single European nation - to compete with the US and Asia unification of our scattered efforts is essential. Failure to plan now risks not only that our picture of Natures laws remain fundamentally incomplete but also that leadership in the field enjoyed by Europe for 20 years falls away. EU FP7 input now is timely and will have major strategic impact, guaranteeing coherence and stimulating national funding.


Grant
Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: NMP-2007-2.4-2 | Award Amount: 3.87M | Year: 2008

Hierarchically organised metal organic catalysts shall be developed which can be easily recycled in multi-batch processes or which can be used in continuous processes without loosing the original advantages of the corresponding homogeneous soluble metal organic catalysts - high selectivity, activity and stability. The catalysts will be constructed using components at the nano-scale in a bottom-up approach. Hereby, catalytically active metal complexes will be linked with nanoparticles such as polymeric microgels, hyperbranched polymers or hybrid systems consisting of silsesquioxanes attached to hyperbranched polymers. Further hierarchical organisation of HiCat catalysts will be accomplished by interconnected networks formed from the assemblies of catalytic nanoparticles using end-functional T-responsive polymers that can interact with functionalities on the surface of the nanoparticles as binding agents. Recycling of the catalyst-nanoparticle entities in multi-batch operation will be studied utilizing the change of solubility of the polymer supported catalysts by external stimuli. Based on polymer-nanoparticles linked by T-responsive polymers, new types of films and membranes with graded porosity can be prepared by varying the size of the nanoparticles and the length of T-sensitive polymers. This opens new opportunities for integration of catalytic steps and separation within the hierarchically structured system and, hence for continuous reactor operation. The proposal combines the superiority of homogeneous metal-organic catalysts often possessing nearly 100 % selectivity with the advantage of efficient separation by grabbing a new concept for building up hierarchically organised catalytic systems. Structural principles of tailor-made ligands will be transferred into tailor-made functional surfaces of nanoparticles. For proof of principle of the concept, three types of reactions will be studied: olefin metathesis, CX coupling and enantioselective hydrogenation.


Grant
Agency: Cordis | Branch: FP7 | Program: MC-ITN | Phase: FP7-PEOPLE-2012-ITN | Award Amount: 3.74M | Year: 2014

The main goal of the project is to provide excellent initial training to young researchers in the field of high energy particle physics, paving the road for new discoveries about the fundamental nature of the Universe at a time when new discoveries are expected, and when the new Standard Model of Particle Physics is going to be forged. The research goal of HiggsTools is the investigation of electroweak symmetry breaking. This question lies at the very frontier of knowledge of theoretical particle physics and phenomenology and, in fact, the primary goal of the Large Hadron Collider (LHC) at CERN is to unveil the mechanism of electroweak symmetry breaking. During the period of the network it is certain that the mechanism of electroweak symmetry breaking will be further decoded and that the theoretical ideas that date back to 1964 will either be confirmed or supplemented through the discovery of new additional particles that contribute to it. The experiments at the LHC have already made an impressive step forward in answering this question, by discovering a particle that is looking more and more like a Higgs boson. It remains an open question, however, whether this is the Higgs boson of the Standard Model of particle physics, or possibly the lightest of several bosons predicted in some theories that go beyond the Standard Model. Finding the answer to this question will take time. The outcome of the Higgs studies at the LHC will either carve our present understanding of electroweak interactions in stone or will be the beginning of a theoretical revolution. We will therefore create a cohort of 21 early-stage researchers (ESR) who will all be in the network for the same 36 month period and therefore be able to obtain the full benefit from the training provided by the network. We request 500 person-months for early-stage researchers (ESR) in accordance with the rules of the People FP7 Programme. The remaining 256 person-months will be funded from local sources.


Grant
Agency: Cordis | Branch: FP7 | Program: CPCSA | Phase: INFRA-2010-1.2.3 | Award Amount: 3.09M | Year: 2010

Partners to this proposal include the six major global programmes exploring the full extent of species diversity, a core dimension in human knowledge of global biodiversity.\nThey are: GBIF and distribution modelling, the EBI/INDSC, and Barcode of Life initiatives and molecular diversity, IUCN Red Lists and the species conservation movement, and the Species 2000 Catalogue of Life taxonomic framework. These will work closely with ELIXIR and LifeWatch, the ESFRI Infrastructures covering biodiversity, and build on the 4D4Life Project that develops the internal e-infrastructure of the Catalogue of Life.\nThe i4Life project is to establish a Virtual Research Community that will enable each of these global projects to engage in a common programme enumerating the extent of life on earth. It builds on the common need of each organisation to specify the entire set of organisms, their growing use of the Catalogue of Life as a common taxonomic resource alongside their own catalogues, and the different expertise that each programme brings to the task.\nThese key players present particular hurdles to Catalogue integration because they a) have established their own architectures, standards and protocols, b) have special requirements, and c) have their own partial catalogues that need to be integrated with the Catalogue of Life in a two way flow.\nIn each case i4Life will design, implement and test the necessary special pipelines, as well as contributing significantly to enhancement of the Catalogue of Life for all to use through the inflows from the partners. By providing access to a common species catalogue within each of the organisations, we expect to contribute a much needed level of knowledge integrity across the various scientific and community studies of the global biota. To make sense of global biodiversity it is vital that these organisations can communicate through a unified view of the extent of life.


Grant
Agency: Cordis | Branch: FP7 | Program: CP-CSA-Infra | Phase: INFRA-2007-2.2-01 | Award Amount: 6.37M | Year: 2008

The Life Watch e-Science and Technology Infrastructure for biodiversity data and observatories will be a large-scale European research infrastructure bringing together: -a system of marine, terrestrial and freshwater observatories; -common access to a huge amount of interlinked, distributed data from databases and monitoring sites; -computational facilities in virtual laboratories with analytical and modelling tools; -targeted user and training support and a programme for public services. The biodiversity research infrastructure will open up new and exciting research opportunities, and will help to enhance the understanding and sustainable management of our natural environment. This preparatory project brings together the interested EU Member and Associated States with the objective to prepare a cooperation agreement on the construction and maintenance of the Life Watch research infrastructure. In addition, the leading networks in biodiversity science and stakeholder institutes are preparing the organisation and logistics for the following construction phase. The current project delivers the technical, legal and financial preparations required for entering and managing the Construction Phase. A range of policy issues are resolved with respect the organisation of the distributed infrastructure, its legal implications, construction logistics, user service, cost analysis and planning. In addition the project makes the necessary preparations in the domain of risk management and quality control. The project is planned to take three years. A Policy and Science Board, populated by the representatives of fourteen potentially interested partner countries and eight cooperating scientific networks, oversees the progress of the preparations. The individual members of the Board act as the liaison with their political domains and the research communities, respectively.


Gorzelak P.,Polish Academy of Sciences | Salamon M.A.,University of Silesia
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2013

Despite a wide array of published actualistic studies on echinoderm taphonomy the detailed pattern of decay and disarticulation of their skeletons is still not well understood. Here we provide results of tumbling experiments using a rotating barrel filled with artificial seawater and medium-sized quartz sand to mimic physical forces experienced by echinoderms during transportation in high-energy conditions. In particular, we determined semi-quantitatively transportation-induced rates and patterns of damage and disintegration of freshly killed ophiuroid, asteroid and crinoid skeletons that were not allowed to decay initially. Our experiments showed that echinoderm specimens disintegrated in a characteristic sequence toward an increase of the degree of disarticulation, abrasion and roundness or thinness of echinoderm ossicles. The sequence of disintegration in crinoids began with the partial disintegration of distal arms after 2. h (a time equivalent to ~. 1. km of transport). The initial split of ophiuroid and asteroid arms and crinoid cirri occurred after 24. h (~. 12. km) and complete destruction of the asteroid mouth and ophiuroid disk area occurred after 72. h (~. 36. km). The duration of transport necessary to promote initial fragmentation in asteroid and ophiuroid arms and crinoid cirri into isolated ossicles was 120. h (~. 60. km). The complete disarticulation of crinoid, ophiuroid and asteroid arms and crinoid cirri occurred after 312. h (~. 156. km) and 408. h (~. 204. km), respectively. Although it has been argued that the quality of preservation can be a poor index of post-mortem transport, echinoderms allowed limited initial decay in the presence of rapid and relatively constant physical disturbance, an approximation of the distance of transport can be made.Our data demonstrate that articulated ossicles can remain for several days, sufficient time for long (even a few hundred. km) transportation. This finding illustrates that articulated echinoderm remains do not necessarily imply low energy and highlights the importance of a reliable discrimination of autochthonous and allochthonous components of fossil echinoderm assemblages. Application of, in particular, isolated fossil echinoderm ossicles in e.g. paleoenvironmental and paleoecological reconstructions may lead to serious misinterpretations and should be supplemented by observations of abrasion traces. © 2013 Elsevier B.V.


News Article | November 30, 2016
Site: www.eurekalert.org

Brain scientists are using tropical fish to investigate how the spinal cord can be coaxed to repair itself after injury. The European research team has received £1.1 million (€1.3m) to investigate how zebrafish are able to repair and replace damaged nerve cells. Researchers will explore how these mechanisms can be triggered in other animals and human cells. They hope their findings will reveal new therapies that could be tested in patients with neurodegenerative conditions, such as motor neuron disease and multiple sclerosis. Such treatments could also help people with certain types of paralysis. The spinal cord carries vital connections between the brain and muscles called motor neurons, which are crucial for controlling movement of the body. Damage to these fragile nerve cells - either by injury or disease - is permanent and results in irreversible paralysis. Zebrafish have the remarkable ability to repair injured connections and replace damaged motor neurons, enabling them to regain full movement within four weeks after injury. They are also able to repair the specialised sheath that surrounds nerve cells - called myelin - which helps speed up the transmission of nerve impulses that control movement. The team - coordinated by the University of Edinburgh - includes brain experts from the French National Institute of Health and Medical Research (Inserm), University Hospital Dresden, DFG Centre for Regenerative Therapies Dresden, the Free University of Brussels (VUB) and the Nencki Institute of Experimental Biology of the Polish Academy of Sciences. Researchers are developing specialised microscope techniques to monitor the mechanisms of nerve cell repair in action. They hope to identify the molecular signals that instruct stem cells in the zebrafish's spinal cord to produce new motor neurons and stimulate repair of the myelin sheath. These factors will then be examined in further animal studies and laboratory tests on human cells. At the end of the three-year study, the researchers hope to identify potential therapies that can be taken forward into clinical trials involving patients with neurodegenerative diseases. The study is funded by the European Commission through the European Research Area Network for Neuroscience Research (ERA-NET NEURON) and co-funded through national funding agencies. Lead researcher Professor Catherina Becker, Director of the University of Edinburgh's Centre for Neuroregeneration, said: "This exciting project brings together leading experts from across Europe to explore the intrinsic capacity of the spinal cord to repair itself. We hope this will eventually lead to urgently needed therapies for people who have damage to their spinal cord, either from disease or injury."


News Article | November 17, 2016
Site: www.bbc.co.uk

Scientists have improved "the most important biological process on the planet" - photosynthesis. The breakthrough, published in the journal Science, used genetic modification to increase the amount of sunlight energy crop plants can channel into food production. That increased yield in an experimental crop by 15%. Researchers say this is a critical step towards increasing crop production to feed a growing global population. Lead researcher Prof Stephen Long, based at the the University of Illinois and the University of Lancaster, said decades of research into the 140-step process by which plants convert sunlight energy into food had revealed specific "inefficiencies in crops". "There are bottlenecks holding up the conversion of sunlight energy into food," he told BBC News. "Our research has tackled one of those bottlenecks." The scientists targeted a plant's natural Sun-protection mechanism - while plants have evolved to produce food using sunlight energy, they have also evolved to protect themselves from Sun damage, which slows the process down. "[To protect itself], the leaf induces a process that gets rid of excess energy as heat," Prof Long told BBC News. "But the problem is when a cloud moves across the Sun, there's less sunlight energy - the plant could use it all, but it carries on dispensing that energy as heat. "So what we've done is speed up the process by which that heat loss [switches off]." The team inserted extra copies of the genes responsible for this heat-loss switch. And when they then grew their genetically modified crop, it grew 15% larger than normal. "This is a big jump," said Prof Long. "Well, we're now making this change in rice, in soy bean and wheat; [15% in those] would be huge. "Globally - rice, wheat, maize and soybean are the biggest crops. "So if we could get the same increase in those, that would greatly alleviate what we see as the future pressure on food supply. " That pressure will intensify in the coming few decades, according to the United Nations Food and Agriculture Organisation (UNFAO). By 2050, it projects, the world will need to grow 70% more food, as the global population rises to more than nine billion people. "At the current rate we're not going to come close to reaching that target, so we're really in desperate need of new innovations," said Prof Long. "For us [in the West], food prices will go up. "But for some of the poorest nations, many households are already spending almost 100% of their household income on food, so for those families and those countries, this will be a catastrophe." Dr Hans Dreyer, from the UNFAO's of the plant production and protection division, said: "This is just one change, and we don't yet know if these plants will require more of other resources like water. "It's really important to increase crop yields significantly, but also sustainably." Prof Christine Foyer, who directs a food security project for Sub-Saharan Africa at the the University of Leeds, described the breakthrough as "vital". "In terms of making Africa green and solving the problems associated with agriculture in those parts of the world," she told BBC News, "improving the processes involved in photosynthesis is an important step in solving food security. "Many people in the world today don't get enough to eat. And it's possible to envisage, with these new developments, that we can achieve zero hunger within the next 20 years. "I would hope that poor farmers would have plants that would grow well across a wide range of environmental conditions. So if you end up in drought or flood, you could have crops that remain viable. "Giving people with very little the wherewithal the feed themselves, that's what matters." This research involved collaborators from the Polish Academy of Sciences and the University of California Berkeley.


News Article | November 30, 2016
Site: www.eurekalert.org

Going against the grain - nitrogen turns out to be hypersociable! Nitrogen is everywhere: even in the air there is four times as much of it as oxygen. However, it is reluctant to form chemical bonds, especially with more than four atoms. Chemists from Warsaw predict, however, that contrary to the rules of typical chemistry, in appropriately selected conditions there may be a nitrogen that nobody has ever seen: one capable of forming up to six chemical bonds. Nobody expected this. Computer simulations suggest that nitrogen, a very well-known element, with a reputation for being reluctant to react could, at a high enough pressure, break the chemical rules and become extremely gregarious: a single atom would then be able to form even six chemical bonds. This surprising discovery has been made by researchers at the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw and the New Technology Centre at the University of Warsaw (CeNT UW), funded by grants from the Polish National Science Centre. Chemists have long known that nitrogen may occasionally have a valency of five, which means that it is potentially able to form bonds with five other atoms. Another element with similar properties is phosphorus, which is adjacent to nitrogen in the periodic table. "Nitrogen, however, behaves differently to phosphorus: in practice, it forms five bonds with at most four other atoms, and more usually with three, as in the popular nitric acid HNO3. We decided to investigate, using the computer, the possibility of obtaining a compound in which pentavalent nitrogen would combine with five neighbours by covalent interactions - chemical bonds. We analyzed thousands of crystal structures of nitrogen compounds with fluorine arising at high pressures. We were hoping to see some structures containing nitrogen pentafluoride NF5 particles. We were completely unprepared for the fact that in one of the crystals we ran into ions with the formula NF6- in which the nitrogen atom bonds with as many as six fluorine atoms," says Dr. Patryk Zaleski-Ejgierd (IPC PAS). Dr Dominik Kurzydlowski (CeNT UW), co-author of the publication in the journal Scientific Reports, explains the essence of the discovery as follows: "Two electrons are typically required for the formation of a single covalent bond. The problem with nitrogen lies in the fact that when creating various compounds it 'trades' electrons so as to always be surrounded by eight of them. This constrains the total number of atoms bonded to nitrogen to no more than four. We were the first to find a stable crystal in which nitrogen breaks the octet rule, i.e. the requirement to possess exactly eight electrons, and forms bonds involving a total of up to twelve electrons." Compounds in which an element breaks the octet rule octet are called hypervalent. Many elements can form hypervalent compounds, including phosphorus, sulphur and various metals. This phenomenon is advantageous because it significantly widens the number of possible compounds the element can form. For example, if it were not for hypervalency, sulphur would not form sulphuric acid and phosphorus could not be one of the building blocks of DNA. The calculations and simulations associated with the search for hypervalent nitrogen were carried out at the IPC PAS using density functional theory, that is, the method normally used in solid state calculations. However, the discovery's authors used one of the more advanced embodiments of this theory, the hybrid functional. It makes it possible to describe chemical bonds very accurately, but it takes much longer to perform the calculations. "The compounds we tested, as well as the conditions under which these compounds were formed, were very exotic. The accuracy of the calculations was therefore our absolute priority which is why we decided to use the hybrid functional for the calculations," says Dr. Kurzydlowski and stresses that carrying out the simulation within a reasonable timeframe was made possible thanks to cooperation with the Interdisciplinary Centre for Mathematical and Computational Modelling, University of Warsaw. A thorough analysis of the results of computer simulation allowed the researchers to identify the unique crystal structure that with an increase in pressure at some point automatically ionizes in a very particular way. A reorganization takes place during which the molecular crystal, originally formed of a mixture of gases NF3 and F2, transforms into a complex ionic crystal constructed of NF4-, NF2+ and... NF6- ions. (It should be mentioned here that despite the exotic name, ionic crystals are common in nature. They include many minerals, among others popular rock salt, whose crystal structure is formed of sodium cations Na+ and chloride anions Cl-). The pressure required for the synthesis of crystals containing NF6- amounts to 400-500 thousand atmospheres which is within the reach of current experimental techniques. Simulations suggest that after formation the crystals would remain metastable even at much lower pressures. Does that also mean under normal atmospheric pressure? "I wouldn't bet too much money on that, but it cannot be completely ruled out that one day you will simply be able to pick up the crystals we predict with unique NF6- ions. If they do turn out to be so stable, who knows, perhaps it will be possible to find some interesting applications for them?" wonders Dr. Zaleski-Ejgierd. However, taking a crystal with NF6- ions into your hand would probably not be a very good idea. Nitrogen trifluoride is already a strong oxidizing agent that must be stored in steel cylinders. A crystal of nitrogen pentafluoride mixed with NF6- would be an even stronger oxidant and we can assume that even the construction of a container allowing for its safe storage could cause engineers considerable difficulties. The Institute of Physical Chemistry of the Polish Academy of Sciences was established in 1955 as one of the first chemical institutes of the PAS. The Institute's scientific profile is strongly related to the newest global trends in the development of physical chemistry and chemical physics. Scientific research is conducted in nine scientific departments. CHEMIPAN R&D Laboratories, operating as part of the Institute, implement, produce and commercialise specialist chemicals to be used, in particular, in agriculture and pharmaceutical industry. The Institute publishes approximately 200 original research papers annually.


Broniowski W.,Jan Kochanowski University | Broniowski W.,Polish Academy of Sciences | Ruiz Arriola E.,University of Granada
Physical Review Letters | Year: 2014

We argue that relativistic nuclear collisions may provide experimental evidence of α clustering in light nuclei. A light α-clustered nucleus has a large intrinsic deformation. When collided against a heavy nucleus at very high energies, this deformation transforms into the deformation of the fireball in the transverse plane. The subsequent collective evolution of the fireball leads to harmonic flow reflecting the deformation of the initial shape, which can be measured with standard methods of relativistic heavy-ion collisions. We illustrate the feasibility of the idea by modeling the C12-Pb208 collisions and point out that very significant quantitative and qualitative differences between the α-clustered and uniform C12 nucleus occur in such quantities as the triangular flow, its event-by-event fluctuations, or the correlations of the elliptic and triangular flows. The proposal offers a possibility of studying low-energy nuclear structure phenomena with "snapshots" made with relativistic heavy-ion collisions. © 2014 American Physical Society.


Carstensen J.,University of Aarhus | Weydmann A.,Polish Academy of Sciences
Ambio | Year: 2012

Arctic ecosystems have experienced and are projected to experience continued large increases in temperature and declines in sea ice cover. It has been hypothesized that small changes in ecosystem drivers can fundamentally alter ecosystem functioning, and that this might be particularly pronounced for Arctic ecosystems. We present a suite of simple statistical analyses to identify changes in the statistical properties of data, emphasizing that changes in the standard error should be considered in addition to changes in mean properties. The methods are exemplified using sea ice extent, and suggest that the loss rate of sea ice accelerated by factor of *5 in 1996, as reported in other studies, but increases in random fluctuations, as an early warning signal, were observed already in 1990. We recommend to employ the proposed methods more systematically for analyzing tipping points to document effects of climate change in the Arctic. © 2012 Royal Swedish Academy of Sciences.


Piotrkiewicz M.,Nalecz Institute of Biocybernetics and Biomedical Engineering | Hausmanowa-Petrusewicz I.,Polish Academy of Sciences
Journal of Physiology | Year: 2011

Motor unit (MU) potentials were registered from 20 ALS patients and 13 age-matched control individuals during isometric constant force contractions of brachial biceps (BB). The registered signals were decomposed into single MU potential trains. The estimates of duration of the afterhyperpolarisation (AHP) in MNs, derived from the interspike interval variability, was compared between ALS patients (124 MNs) and control subjects (111 MNs) and no significant differences were encountered. However, the relationship between TI and age for patients appeared to be qualitatively different from that of the control group. The dependence of patients' AHPs on relative force deficit (RFD), which quantified muscle involvement, was more specific. For RFDs below 30%, the AHP estimate was significantly lower than control values and then increased thereafter with increasing RFDs. Moreover, firing rates of patients with the smallest RFDs were significantly higher while firing rates of patients with the greatest RFDs were significantly lower than control values. The AHP shortening in the early stages of muscle impairment is consistent with the decrease in firing threshold of 'fast' MNs found in spinal cord slices from neonatal SOD1 mice. The later elongation of the AHP may be caused by the higher vulnerability of 'fast' MNs to degeneration and by the influence of reinnervation. Our results are comparable to what has been observed in acute experiments in animal models, providing a bridge between animal and clinical research that may be relevant for identification of mechanism(s) underlying neurodegeneration in ALS. © 2011 The Authors. Journal compilation © 2011 The Physiological Society.


Shabalin I.,University of Virginia | Dauter Z.,Argonne National Laboratory | Jaskolski M.,Adam Mickiewicz University | Jaskolski M.,Polish Academy of Sciences | And 2 more authors.
Acta Crystallographica Section D: Biological Crystallography | Year: 2015

The anticancer activity of platinum-containing drugs such as cisplatin and carboplatin is considered to primarily arise from their interactions with nucleic acids; nevertheless, these drugs, or the products of their hydrolysis, also bind to proteins, potentially leading to the known side effects of the treatments. Here, over 40 crystal structures deposited in the Protein Data Bank (PDB) of cisplatin and carboplatin complexes of several proteins were analysed. Significant problems of either a crystallographic or a chemical nature were found in most of the presented atomic models and they could be traced to less or more serious deficiencies in the data-collection and refinement procedures. The re-evaluation of these data and models was possible thanks to their mandatory or voluntary deposition in publicly available databases, emphasizing the point that the availability of such data is critical for making structural science reproducible. Based on this analysis of a selected group of macromolecular structures, the importance of deposition of raw diffraction data is stressed and a procedure for depositing, tracking and using re-refined crystallographic models is suggested. © 2015 International Union of Crystallography.


Fichet S.,São Paulo State University | Von Gersdorff G.,São Paulo State University | Von Gersdorff G.,Pontifical Catholic University of Rio de Janeiro | Royon C.,University of Kansas | And 2 more authors.
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2016

We consider the possibility that the diphoton excess at 750 GeV is caused by a new scalar resonance produced in photon fusion. This scenario is parametrized by only one relevant effective couplings and is thus minimal. We show that this setup can reproduce both the production rate and width of the resonance, and is not in conflict with the 8 TeV limits on the diphoton cross section. The scenario also predicts event rates for WW, ZZ, Zγ final states. We suggest for one to perform precision measurements by studying light-by-light scattering with intact protons detected in forward detectors. We construct a simple model that shows that the required couplings can be achieved with new vectorlike, uncolored fermions (with a strong Yukawa coupling to the resonance) which may also account for the required width. © 2016 American Physical Society.


Rudnicki A.,Albert Ludwigs University of Freiburg | Rudnicki A.,Polish Academy of Sciences
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2015

We improve the entropic uncertainty relations for position and momentum coarse-grained measurements. We derive the continuous, coarse-grained counterparts of the discrete uncertainty relations based on the concept of majorization. The entropic inequalities obtained involve two Rényi entropies of the same order, and thus go beyond the standard scenario with conjugated parameters. In a special case describing the sum of two Shannon entropies, the majorization-based bounds significantly outperform the currently known results in the regime of larger coarse graining, and might thus be useful for entanglement detection in continuous variables. © 2015 American Physical Society.


Zawiejska J.,Pedagogical University of Cracow | Wyzga B.,Polish Academy of Sciences
Geomorphology | Year: 2010

Spatial and temporal patterns of the twentieth-century channel changes of the Dunajec, the second largest river of the Polish Carpathians, are analysed using data from six historical maps, hand-auger drillings in paleochannels and hydrometric data from 10 gauging stations. In its lower course, the river was considerably narrowed, shortened and embanked between the 1880s and the 1920s. Here, bed degradation commenced in the late 19th-century and has so far resulted in 3.1 m of channel incision. In the middle river course, little change occurred in mountain reaches where the Dunajec is confined by valley sides and where bedrock exposures prevent channel incision. In the reaches within intramontane basins, channelization works carried out in the 1950s-1970s considerably narrowed the river and transformed its multi-thread channel into a single-thread, straight channel. Rapid bed degradation induced by the works resulted in up to 2 m of channel incision over the second half of the century. Upstream progression of bed degradation into the adjacent mountain reach was hindered by bedrock exposures at its downstream end. In the upper river course, reaches with the deeply incised channels (up to 3.5 m) prevail over a few past decades in response to gravel exploitation, river channelization and a reduction in catchment sediment supply. More scarce are vertically stable reaches, which owe their stability to low unit stream power in wide, unmanaged reaches and to fixing of the channel bed by drop structures in channelized reaches. This study shows that despite the overall tendency to incision over the 20th century, considerable differences in the timing and course of channel changes occurred between particular river reaches due to variable human impact and local geological and geomorphological conditions. The main phase of channel incision took place progressively later in the upstream direction. However, upstream progression of bed degradation from the already incised downstream reaches was precluded by the Rożnów Dam and bedrock-controlled reaches. Where bed material flushed out from an incising upstream reach had been introduced into an artificially narrowed channel of high transport capacity, it was easily transferred downstream and could not restore the downstream reach to its pre-channelization vertical position. © 2009 Elsevier B.V. All rights reserved.


Grant
Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: ENV.2010.4.2.3-1 | Award Amount: 1.84M | Year: 2010

InContext will investigate drivers and barriers for sustainability and their interplay on an individual and collective level. InContext assumes that both individual and collective behaviours respond to an external context (like social norms, policies, and infrastructure) and an internal context (like needs, values and priorities). So far, initiatives to further sustainable development have focused mainly on external contexts. InContext argues that it is essential to address both sides and include factors like individual needs or subconscious aspects to successfully bridge the gap between awareness and action at individual and collective levels. InContext will: Study internal and external contexts and the way individuals respond to them to identify drivers and barriers to actions advancing sustainable development. Conduct participatory scenario development and back-casting exercises in three local communities to generate findings on innovative mechanisms for co-operation and the identification of agents for change. Improve the understanding of the interplay between internal factors and external factors to behaviour, thereby generating results with regard to the interaction between structural and agent-based factors. Improve the understanding of how policies at EU and local levels (as part of the external context) can help address the internal context in a way that supports sustainability-driven action. Identify a set of innovative policy mixes for sustainability-driven action considering the roles of actors on different levels such as policy and opinion makers, business and civil society. InContext attaches great importance to the applicability and distribution of its research results. This concern is reflected in the project design by the integration of a network of local governments and the setting up of an interdisciplinary advisory board allowing for a permanent communication and reality-check by political as well as business professionals.


Grant
Agency: Cordis | Branch: FP7 | Program: CP | Phase: ICT-2009.5.1 | Award Amount: 8.53M | Year: 2010

Heart failure (HF) is the most increasing cause of death in Western Countries. For that reason, together with the difficulty of having a sufficient number of donor organs, it is recognized that the device-based therapeutic approaches will assume an increasingly important role in treating the growing number of patients with advanced heart failure, not only as bridge to transplant, but also as destination therapy, by considering also the ageing population. SensorART will provide: innovative telemedicine services supporting patients with chronic heart failure and healthcare professionals, allowing patients to be treated at home without renouncing to accessing high medical expertise; innovative tele-control services allowing the patient and the healthcare professional to keep under control the performance of cardiovascular implanted assist devices (VAD); demonstration of effectiveness and cost effectiveness of specialized telemedicine services and the positive impact on the healthcare system reducing hospitalisation time, by considering also the higher degree of device acceptability at home by a training of the patient and his empowerment. The psychological support, evaluation and counselling before and after implantation will be strongly considered, by taking into consideration the importance of brain-heart and brain-homeostasis recover relations; circulatory modelling and simulation of cardiac and circulatory dynamics will be adapted to reconstruct the patients status and analyse separately the effects of heart and circulatory conditions along with the assistance conduction, through this application, novices will have the possibility to make himself familiar with VADs, while gaining in-silico experience in treating acute heart failure; analysis and exploitation of the medical device market by the development of an open, standardized interoperable system able to easily interact with the existing products.


Grant
Agency: Cordis | Branch: FP7 | Program: CP | Phase: SPA-2007-2.1-01 | Award Amount: 1.38M | Year: 2008

The European Space Agencys project MATROSHKA (MTR), dedicated to determine the radiation load on astronauts in- and outside the International Space Station (ISS), launched in Jan. 2004 and is currently in its experimental phase 3. MTR is an anthropomorphic upper torso phantom containing over 6,000 radiation detectors to determine the depth- and organ dose distribution in the body. It is the largest international research initiative performed in the field of space dosimetry, combining the expertise of leading research institutions all over the world. Consequently it generates a huge pool of data of immense value. Aiming at optimal scientific exploitation, the project HAMLET will bring together a European expert committee, consisting exclusively of members of the MTR consortium, to process and compile the data acquired individually. Based on experimental input as well as on radiation transport calculations, a three-dimensional model for the dose distribution in an astronauts body will be built up. The results describe the exposure conditions both for extra-vehicular activities (MTR-1:200405) and inside the ISS (MTR-2A/B:200608). The project goes beyond essential data analysis and incorporates a modelling approach to guide new experimental measurements and strengthen the predictive capacity. This allows further utilization of the data, particularly with respect to detailed modelling of radiation interactions in the human body. The scientific achievements contribute essentially to radiation risk estimations for future interplanetary human missions, putting them on a solid experimental and theoretical basis. The synthesis of data, considerably extending previous knowledge, constitutes a major accomplishment by which Europe can establish worldwide leadership in this special branch of space radiation research. Public outreach is assured by making the data and reports available to the scientific community and the public via a web-based database and a dedicated homepage.


Grant
Agency: Cordis | Branch: H2020 | Program: CSA | Phase: INFRAINNOV-02-2016 | Award Amount: 2.28M | Year: 2017

Development and construction of accelerator based scientific Research Infrastructures are going through a deep paradigm change because of the need for large scale Technological Infrastructures at the forefront of technology to master the key accelerator and magnet science and technology needed for several fields. Indeed, because of the high technological level and of the increased size and time scale of projects, development and construction require more and more sophisticated R&D platforms on key accelerator and magnet technologies, large-scale facilities for their assembly, integration and verification, large concentrations of dedicated skilled personnel and long term relationships between laboratories and industry. In response to those challenges, a few large platforms specialized in interdisciplinary technologies and for applications of direct benefit to society are emerging. The emerging Technological Infrastructure is aiming at creating an efficient integrated ecosystem among laboratories focussed on R&D, with a long term vision for the technological needs of future RIs and industry, including SME, motivated by the innovative environment and the market created by the realisation of the technological needs of several RIs. With a timeline of 30 months, involving 10 Consortium partners, the AMICI proposal will ensure that A) a stronger and optimised integration model between the large existing technological infrastructures is developed and agreed upon, B) that this integrated ecosystem is attracting industries and fostering innovation based on accelerator and SC magnets cutting-edge developments, C) that strategy and roadmaps are clearly defined and understood to strongly position European industries and SMEs on the market of the construction of new Research Infrastructures worldwide, and D) that potential societal applications are identified and disseminated to the relevant partners of this ecosystem.


Grant
Agency: Cordis | Branch: H2020 | Program: MSCA-ITN-ETN | Phase: MSCA-ITN-2015-ETN | Award Amount: 3.84M | Year: 2016

Our vision is to develop a suite of standardised non-invasive devices that will provide essential information about brain health in neurocritical care and neuromonitoring, with a particular emphasis on 1. traumatic brain injury: the silent epidemic of the third millennium and 2. hypoxia in newborn children. Survivors present permanent neurological conditions that have a profound impact on the quality of life of individuals and their families, and hence a large socio-economic impact. The key factors influencing these conditions and their treatment are the avoidance of brain hypoxia and metabolic disturbances and this is driving the transfer of new neuromonitoring systems to the bedside where they are being shown to have a transformative effect on patient care. BitMap will develop non-invasive photonics-based monitoring techniques and data analysis methods to provide biomarkers that could guide patient management. A cohort of multi-disciplinary Early Stage Researchers (ESRs), embedded in leading laboratories across Europe, will work together on an programme designed to address the key technological and clinical challenges in neurocritical care. The ESRs will benefit from the diverse range of expertise in advanced photonics and clinical application which will substantially enhance their research competitiveness and employability, and will together form a critical mass of skilled people working together towards new technologies for improved neuroclinical care. The challenges involved are fundamentally multi-disciplinary and therefore ESRs trained in a multi-disciplinary environment are essential if progress and clinical impact is to be made. There is currently no graduate programme producing researchers with these attributes, but there is a significant market for such PhDs in the rapidly developing area of biomedical optics and in general in medical imaging technology development. The BitMap project therefore addresses both a clinical and economic need.


Grant
Agency: Cordis | Branch: FP7 | Program: CP-TP | Phase: NMP-2007-1.2-2 | Award Amount: 3.07M | Year: 2008

This proposal aims at the development and application of an innovative single molecule workstation, enabling advances in the research happening throughout Europe and the rest of the world around the investigation of living cells. By combining three most advanced microscopic techniques into a single workstation, we aim at reaching a new quality level in the study of the molecular biology of living cells. The proposed single molecule workstation will be composed of three key elements: (i) inverted light microscope (ILM); (ii) atomic force microscope (AFM); and (iii) optical tweezers (OT). A true virtue of this initiative is that by combining several ultra-sensitive microscopy techniques into a single workstation completely new horizons for molecular biology related studies are opened. The aim of this combined ILM-AFM-OT setup is to look at the surface topography using high-resolution AFM, to study the distribution of cellular molecules using high sensitive fluorescence and contrast enhanced light microscopy (ILM), and to measure molecular interaction forces with ultra-sensitive optical tweezers. As a complementary method, photo-thermal nano-spectroscopy (PTNS) will be used to investigate spectroscopic properties of cellular material with a spatial resolution down to sub-100 nm which will enable chemical analysis of sub-cellular components. The combined setup will provide a qualitatively new level in microscopic studies, giving unprecedented versatility in the detection and monitoring of cellular events with highest spatial and temporal resolution. The proposed single workstation will be used for the study of the correlation between structure and function of living cells with applications in immunology and cancer research.


Grant
Agency: Cordis | Branch: H2020 | Program: CSA | Phase: MSCA-NIGHT-2014 | Award Amount: 443.72K | Year: 2014

The project Malopolska Researchers Night will be implemented in the years 2014 and 2015 respectively for the eighth and ninth time. The event has already permanently inscribed in the calendar of Malopolska scientific events, enjoying growing from year to year popular among participants and becoming one of the biggest Nights in Europe. In 2013, this event was attended by over 55 thousand people, while in the first year of the project (2007) the event was attended only by 3.5 thousand people. The event program specified in the application is even richer than before it will take over 1 thousand activities, mainly interactive workshops, presentations, demonstrations and experiments as well as shows with the participation of scientists. It is estimated that 60 thousand people will participate in the events in 2014 and 65 thousand people in 2015. Malopolska Researchers Night is to first of all show participants how interesting is the work of scientists and how fascinating they are people. Through fun, in accessible and understandable way for everybody, we want to show that all around us is the science, and that scientists in their laboratories are working every day to make our life better, easier and more modern. The main motto of the project for the years 2014 and 2015 will be to present the successes of Malopolska scientists working in international scientific-research teams. The event will be held in six cities of the Region: Krakow, Tarnow, Nowy Sacz and Niepolomice and - for the first time in 2014 - also in Skawina and Andrychow. In addition, it is planned the live broadcast from selected locations via event website. The program will be prepared by almost 900 researchers, more than 1 600 students, about 120 research groups from more than 30 partners. Thanks to the extensive promotional campaign the information about the event will reach to nearly 3.5 million people each year.


News Article | October 26, 2016
Site: www.eurekalert.org

World-renowned scientists - Prof. Ryszard Kierzek from the Institute of Bioorganic Chemistry Polish Academy of Sciences in Poznan and Prof. Douglas H. Turner from the University of Rochester - are the winners of the 2016 edition of the Poland - U.S. Science Award. The award is granted jointly by the Foundation for Polish Science, the biggest private institution supporting science in Poland, and the American Association for the Advancement of Science (AAAS), the world's largest general scientific association. The award is presented to a pair of scientists, one working in Poland and one in the United States, for outstanding scientific achievements resulting from their collaboration. This award highlights the role of Polish American scientific cooperation. It shows that the outcomes of this cooperation are great scientific achievements, which result from complimentary work on the part of both scientists. Their shared achievements would have been impossible had they worked separately. "We hope that the successes of our laureates become an inspiration for conducting joint scientific investigations for other researchers," said Prof. Maciej Zylicz, President of the Foundation for Polish Science. Professors Kierzek and Turner are being recognized for their research on thermodynamics, biology and structure of ribonucleic acid (RNA) and RNA chemical synthesis. The researchers started their cooperation more than 30 years ago. Because of their scientific work, it has become possible to predict the structure of any RNA based on its sequence. Their research also elucidated RNA folding rules and the use of modified oligonucleotides to modulate biological activity of pathogenic RNAs. Just one of the applications of this new knowledge is inhibiting the growth of the influenza virus. Since the onset of Prof. Kierzek and Prof. Turner's work, the thermodynamics and structure of RNA has had a great influence on the scientific community, especially on biochemists and biologists. Their collaboration has been hugely fruitful, with more than 60 joint publications, all with numerous citations. Prof. Ryszard Kierzek graduated with a degree in chemistry at Adam Mickiewicz University in Poznan. He obtained his Ph.D. in 1978 at the Polish Academy of Sciences Institute of Bioorganic Chemistry. He worked as a postdoctoral fellow at City of Hope National Medical Center and research fellow at the University of Colorado at Boulder, as well as acting as a visiting professor at the University of Rochester. Presently, he is the head of RNA Chemistry and Biology Laboratory at the Institute of Bioorganic Chemistry Polish Academy of Sciences in Poznan. In his research he uses the chemistry, biology, thermodynamics, bioinformatics and structure of RNA to modulate biological activity of RNA correlated with human diseases. He has published 150 scientific articles, which have been cited more than 6,000 times. He is a laureate of the Foundation for Polish Science MISTRZ award. Prof. Douglas H. Turner studied chemistry at Harvard University. He obtained his Ph.D. in physical chemistry at Columbia University. After his postdoctoral fellowship at the University of California at Berkeley, he became a professor of chemistry at the University of Rochester, and works there to this day. Prof. Turner is an internationally acclaimed expert on biophysics of RNA, especially in RNA thermodynamics. The parameters he developed, known as "Turner Rules," allow for the prediction of RNA folding. He has published more than 230 scientific articles, cited more than 15,000 times. The Poland - U.S. Science Award was established in 2013. It is granted once every two years in a competition based on nominations. A Jury of eminent scientists from Poland and the United States chooses the awardees using the opinions of external experts. Prof. Mariusz Jaskólski of Adam Mickiewicz University in Poznan, Poland, and Dr. Alexander Wlodawer of the National Cancer Institute, USA, were the first winners of the Poland - U. S. Science Award. The Jaskólski - Wlodawer team received the award for studies in structural biology. This second competition saw 29 nominations. The awards ceremony will be held in Warsaw on November 15, 2016. Each of the winners will receive the equivalent of five thousand U.S. dollars. The American Association for the Advancement of Science (AAAS) is the world's largest general scientific society and publisher of the journal Science as well as Science Translational Medicine, Science Signaling, a digital, open-access journal, Science Advances, Science Immunology, and Science Robotics. AAAS was founded in 1848 and includes nearly 250 affiliated societies and academies of science, serving 10 million individuals. Science has the largest paid circulation of any peer-reviewed general science journal in the world. The non-profit AAAS is open to all and fulfills its mission to "advance science and serve society" through initiatives in science policy, international programs, science education, public engagement, and more. For the latest research news, log onto EurekAlert!, the premier science-news Web site, a service of AAAS. See http://www. . The Foundation for Polish Science was established in 1991. It is a non-governmental, non-political, non-profit institution based in Warsaw, Poland, with the mission of supporting science. It is the largest source of science funding in Poland outside of the state budget. The Foundation awards prizes, stipends, subsidies and grants to leading scientists and research teams, encourages the transfer of scientific achievements to business practice and supports all kinds of initiatives that serve science in Poland. The funding is awarded by way of a competition, where the most important criterion in granting support is scientific excellence. The achievements and output of FNP competition entrants is evaluated by scientists respected in their fields - both Polish and international. The Foundation offers over a dozen diverse programmes for scientists at different stages of their research careers. The motto of FNP is: "Supporting the best, so that they can become even better". http://www.


News Article | January 26, 2016
Site: phys.org

The new study, published in Plant, Cell and Environment, addresses a central challenge of transgenic plant development: how to reliably evaluate whether genetic material has been successfully introduced. Researchers at the University of Illinois, the Polish Academy of Sciences, the University of Nebraska-Lincoln and the University of California, Berkeley compared the traditional method to several new ones that have emerged from advances in genomic technology and identified one that is much faster than the standard approach, yet equally reliable. The study was led by Illinois postdoctoral fellows Kasia Glowacka and Johannes Kromdijk. "For plants with long life cycles, such as our food crops, this will greatly speed the time between genetic transformation or DNA editing, and development of pure breeding lines," said Long, Gutgsell Endowed Professor of Crop Sciences and Plant Biology and the principal investigator for the study. Long is also a member of the Genomic Ecology of Global Change and Biosystems Design research themes and the Energy Biosciences Institute at the Carl R. Woese Institute for Genomic Biology. To meet the food and fuel needs of an ever-growing global population, researchers benefit from transgenic technologies to develop crops with higher yields and greater resiliency to environmental challenges. None of the technologies used to introduce new genetic material into plants work with 100 percent efficiency. Plants and their offspring must be screened to identify those in which gene transfer was successful. Traditionally, this was done in part by testing successive generations of plants to see if the desired traits are present and breed true over time. In addition, plant scientists can use one of several molecular methods to determine if a gene or genes have actually been successfully introduced into the plant genome. The "tried and true" method, the Southern blot, yields precise data but is slow and unwieldy. It requires isolating relatively large amounts of plant DNA, using fluorescent or radioactive dye to detect the gene of interest, and performing a week's worth of lab work for results from just a few samples at a time. The team compared the Southern blot technique with several that use variations of a chemical process called polymerase chain reaction (PCR). This process allows researchers to quantify specific pieces of the introduced DNA sequences by making many additional copies of them, and then estimating the number of copies—somewhat like estimating the amount of bacteria present in a sample by spreading it on a petri dish and letting colonies grow until they are visible. These methods are much faster than Southern blotting, but if the DNA in each sample does not "grow" at exactly the same rate, the resulting data will be imprecise—size won't be a perfect indicator of the starting quantity. One method examined by Long's group, digital drop PCR (ddPCR), is designed to overcome this weakness. Rather than using the PCR process to amplify all the DNA in a sample, this method first separates each individual fragment of DNA into its own tiny reaction, much like giving each bacterium its own tiny petri dish to grow in. PCR then amplifies each fragment until there are enough copies to be easily detected, and the total number of tiny reactions are counted. Because this method, unlike others, separates the growth-like step from the quantification step, it can be very precise even when the reaction isn't perfect. Results can be obtained in less than two days, and many samples can be processed simultaneously. Long hopes that his group's demonstration that ddPCR is a "reliable, fast and high throughput" technique will help it to become the new standard for those developing transgenic crops. "I believe it will become widely adopted," he said. Although ddPCR is currently more expensive than the other methods, Long said the cost would likely drop quickly, as have the costs of other genomic technologies.


News Article | March 4, 2016
Site: www.nature.com

India funds science In its annual budget released on 29 February, the Indian government increased funding for the Department of Science and Technology (DST) by 17% from last year, to 44.7 billion rupees (US$650 million). The DST is India’s main funding agency and will use the money to initiate research programmes on energy, water and biomedical devices. The Department of Biotechnology received 18.2 billion rupees, a 12% rise. But news was mixed for other divisions: the Department of Health Research’s budget represented a 12% rise compared to 2015–16, whereas the Department of Space got an increase of less than 2%. Pollinators star in biodiversity report The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) announced the findings of its first report on 26 February. The review warns that an ongoing decline in the number of pollinating insects (pictured) and animals threatens global crop production, which depends on pollinators and, as an industry, is worth up to US$577 billion annually. According to the report, the decrease is fuelled by a multitude of factors, including climate change, disease and pesticide use. The IPBES, established in 2012, is modelled roughly on the Intergovernmental Panel on Climate Change. Ebola drug stutters Results from a clinical trial to test experimental Ebola treatment ZMapp failed to show statistically significant results. The drug, developed by Mapp Biopharmaceutical, based in San Diego, California, contains three antibodies and had shown promise in animal studies. According to results presented on 23 February at the Conference on Retroviruses and Opportunistic Infections in Boston, Massachusetts, of 36 people given ZMapp, 78% survived, compared with 61% of 35 patients who did not receive the drug. Mapp was forced to end the clinical trial in January without achieving its goal of enrolling 200 patients because of the waning of the Ebola outbreak. Tetraquark addition Scientists reported findings of a new tetraquark on 24 February. Elementary particles known as quarks usually bind together in groups of two or three, but physicists have observed some composed of four quarks. The new family member, called X(5568), emerged in data from the DZero experiment at the now-inactive Tevatron particle accelerator at Fermilab in Batavia, Illinois. Unlike other examples of tetraquarks, all of which contain at least two quarks of the same type, or ‘flavour’, each of the quarks in X(5568) is different. Studying the particle could help physicists to understand more about the strong force, which holds atomic nuclei together. Gas leak quantified Some 97,100 tonnes of methane leaked out of an underground storage facility run by the Southern California Gas Company in Aliso Canyon, California, researchers reported on 25 February. A team led by Stephen Conley, president of Scientific Aviation in Boulder, Colorado, measured methane concentrations above the site during 13 aircraft flights between 7 November and 13 February. The team calculated that the methane release was equivalent to the annual greenhouse-gas emissions from 572,000 cars. The leak began on 23 October and lasted nearly four months. Memory work wins Three British neuroscientists share this year’s Brain Prize for their work on how memories are formed and lost in the brain. Using different approaches, Timothy Bliss, visiting worker at the Francis Crick Institute in London, Richard Morris at the University of Edinburgh, UK, and Graham Collingridge at the University of Bristol, UK, have shown over the past four decades how a brain mechanism called long-term potentiation underpins the ability to learn and remember by strengthening connections between particular neurons. The €1-million (US$1.1-million) prize was awarded on 1 March by the Grete Lundbeck European Brain Research Foundation in Denmark. Out of deep water A US jury has acquitted a BP site manager who was in charge of the Deepwater Horizon drilling platform during the disastrous spill in 2010, which led to 11 deaths and leaked huge amounts of oil into the Gulf of Mexico (pictured). According to US media reports, Robert Kaluza faced a criminal charge related to the ensuing pollution, but was acquitted by a jury in New Orleans, Louisiana, on 25 February. Kaluza was one of the last BP defendants to face charges over the incident, although the company still has to pay billions in fines. Chemistry petition Chemists are petitioning the chancellor of the University of California, Berkeley, to secure the future of the institution’s College of Chemistry. More than 3,000 people had signed the petition as Nature went to press. Berkeley chancellor Nicholas Dirks announced a “strategic planning process” on 10 February, to try to find solutions to the university’s “substantial and growing structural deficit”. A spokesperson for the university told Nature that although the College of Chemistry could be dissolved as a result of this, no decisions have yet been taken and Berkeley is committed to chemistry research and teaching. Italian protests Researchers held a protest at the Sapienza University of Rome on 25 February, calling the Italian government’s support for research insufficient and erratic. The protest followed a 4 February Correspondence in Nature by Sapienza physicist Giorgio Parisi (G. Parisi Nature 530, 33; 2016) that was supported by 69 researchers. A petition to the Italian government and the European Union started by Parisi had almost 55,000 signatures as of 1 March. Italy spends 1.25% of its gross domestic product on research, but the petition says that the EU should require governments to set a minimum of 3%, as the EU Council of Ministers has advocated in the past. Sequencing suit Genome-sequencing giant Illumina said on 23 February that it has filed a lawsuit against UK-based Oxford Nanopore Technologies, the first company to commercialize nanopore sequencing. The technology reads single bases of genetic material as they pass through a nanoscale pore. The suit, by Illumina of San Diego, California, alleges that Oxford Nanopore has infringed on Illumina patents that describe aspects of using pores to read DNA. Oxford Nanopore has its own suite of patents related to the technology. See go.nature.com/7hydeg for more. Chagas scoop KaloBios Pharmaceuticals of San Francisco, California, is poised to acquire sole distribution rights for a version of benznidazole, one of only two drugs that can treat the insect-borne parasite that causes Chagas disease, after a bankruptcy court ruled in its favour on 26 February. In December, the then chief executive Martin Shkreli announced that the company would price the drug on a level with hepatitis C antivirals, which cost up to US$100,000 per treatment. The first global survey of women’s representation at the highest level of academia shows that just 12% of members of 69 academies surveyed in 2013–14 are female. The Cuban Academy of Sciences had the highest proportion (27%), whereas the Tanzania Academy of Sciences and the Polish Academy of Sciences had the lowest levels, at 4%. Only 40% of the academies had policies that explicitly mention the need for increased participation of women in the academy’s activities. See go.nature.com/cwigqv for more. 947,000 The drop in Japan’s population since 2010, according to the latest census. The population has fallen by 0.7%, to 127.1 million. The decline is the first since records began. 7–11 March The United Nations and Costa Rica Workshop on Human Space Technology convenes in San Jose, Costa Rica. go.nature.com/swmviz 8–10 March Seattle, Washington, hosts the Climate Leadership Conference, to discuss US climate policy and innovation in the wake of the Paris agreement. go.nature.com/pwplig 10 March The US Patent and Trademark Office starts proceedings over who holds the rights to commercialize CRISPR–Cas9 gene-editing technology. go.nature.com/qvnsn8


News Article | January 26, 2016
Site: www.scientificcomputing.com

Arthur Conan Doyle, Charles Dickens, James Joyce, William Shakespeare and JRR Tolkien. Regardless of the language they were working in, some of the world’s greatest writers appear to be, in some respects, constructing fractals. Statistical analysis, however, revealed something even more intriguing. The composition of works from within a particular genre was characterized by the exceptional dynamics of a cascading (avalanche) narrative structure. This type of narrative turns out to be multifractal. That is, fractals of fractals are created. As far as many bookworms are concerned, advanced equations and graphs are the last things which would hold their interest, but there’s no escape from the math. Physicists from the Institute of Nuclear Physics of the Polish Academy of Sciences (IFJ) in Cracow, Poland, performed a detailed statistical analysis of more than one hundred famous works of world literature, written in several languages and representing various literary genres. The books, tested for revealing correlations in variations of sentence length, proved to be governed by the dynamics of a cascade. This means that the construction of these books is, in fact, a fractal. In the case of several works, their mathematical complexity proved to be exceptional, comparable to the structure of complex mathematical objects considered to be multifractal. Interestingly, in the analyzed pool of all the works, one genre turned out to be exceptionally multifractal in nature. Fractals are self-similar mathematical objects: when we begin to expand one fragment or another, what eventually emerges is a structure that resembles the original object. Typical fractals, especially those widely known as the Sierpinski triangle and the Mandelbrot set, are monofractals, meaning that the pace of enlargement in any place of a fractal is the same, linear: if they at some point were rescaled x number of times to reveal a structure similar to the original, the same increase in another place would also reveal a similar structure. Multifractals are more highly advanced mathematical structures: fractals of fractals. They arise from fractals 'interwoven' with each other in an appropriate manner and in appropriate proportions. Multifractals are not simply the sum of fractals and cannot be divided to return back to their original components, because the way they weave is fractal in nature. The result is that, in order to see a structure similar to the original, different portions of a multifractal need to expand at different rates. A multifractal is, therefore, non-linear in nature. “Analyses on multiple scales, carried out using fractals, allow us to neatly grasp information on correlations among data at various levels of complexity of tested systems. As a result, they point to the hierarchical organization of phenomena and structures found in nature. So, we can expect natural language, which represents a major evolutionary leap of the natural world, to show such correlations as well. Their existence in literary works, however, had not yet been convincingly documented. Meanwhile, it turned out that, when you look at these works from the proper perspective, these correlations appear to be not only common, but in some works they take on a particularly sophisticated mathematical complexity,” says Professor Stanislaw Drozdz, IFJ PAN, Cracow University of Technology. The study involved 113 literary works written in English, French, German, Italian, Polish, Russian and Spanish by such famous figures as Honore de Balzac, Arthur Conan Doyle, Julio Cortazar, Charles Dickens, Fyodor Dostoevsky, Alexandre Dumas, Umberto Eco, George Elliot, Victor Hugo, James Joyce, Thomas Mann, Marcel Proust, Wladyslaw Reymont, William Shakespeare, Henryk Sienkiewicz, JRR Tolkien, Leo Tolstoy and Virginia Woolf, among others. The selected works were no less than 5,000 sentences long, in order to ensure statistical reliability. To convert the texts to numerical sequences, sentence length was measured by the number of words (an alternative method of counting characters in the sentence turned out to have no major impact on the conclusions). The dependences were then searched for in the data — beginning with the simplest, i.e. linear. This is the posited question: if a sentence of a given length is x times longer than the sentences of different lengths, is the same aspect ratio preserved when looking at sentences respectively longer or shorter? “All of the examined works showed self-similarity in terms of organization of the lengths of sentences. Some were more expressive — here The Ambassadors by Henry James stood out — while others to far less of an extreme, as in the case of the French seventeenth-century romance Artamene ou le Grand Cyrus. However, correlations were evident and, therefore, these texts were the construction of a fractal,” comments Dr. Pawel Oswiecimka (IFJ PAN), who also noted that fractality of a literary text will, in practice, never be as perfect as in the world of mathematics. It is possible to magnify mathematical fractals up to infinity, while the number of sentences in each book is finite and, at a certain stage of scaling, there will always be a cut-off in the form of the end of the dataset. Things took a particularly interesting turn when physicists from IFJ PAN began tracking non-linear dependence, which in most of the studied works was present to a slight or moderate degree. However, more than a dozen works revealed a very clear multifractal structure, and almost all of these proved to be representative of one genre, that of stream of consciousness. The only exception was the Bible, specifically the Old Testament, which has, so far, never been associated with this literary genre. “The absolute record in terms of multifractality turned out to be Finnegan’s Wake by James Joyce. The results of our analysis of this text are virtually indistinguishable from ideal, purely mathematical multifractals,” says Drozdz. The most multifractal works also included A Heartbreaking Work of Staggering Genius by Dave Eggers, Rayuela by Julio Cortazar, The US Trilogy by John Dos Passos, The Waves by Virginia Woolf, 2666 by Roberto Bolano, and Joyce’s Ulysses. At the same time, a lot of works usually regarded as stream of consciousness turned out to show little correlation to multifractality, as it was hardly noticeable in books such as Atlas Shrugged by Ayn Rand and A la recherche du temps perdu by Marcel Proust. “It is not entirely clear whether stream of consciousness writing actually reveals the deeper qualities of our consciousness, or rather the imagination of the writers. It is hardly surprising that ascribing a work to a particular genre is, for whatever reason, sometimes subjective. We see, moreover, the possibility of an interesting application of our methodology: it may someday help in a more objective assignment of books to one genre or another,” notes Drozdz. Multifractal analyses of literary texts carried out by the IFJ PAN have been published in Information Sciences, the journal of computer science. The publication has undergone rigorous verification: given the interdisciplinary nature of the subject, editors immediately appointed up to six reviewers. Citation: “Quantifying origin and character of long-range correlations in narrative texts” S. Drożdż, P. Oświęcimka, A. Kulig, J. Kwapień, K. Bazarnik, I. Grabska-Gradzińska, J. Rybicki, M. Stanuszek; Information Sciences, vol. 331, 32–44, 20 February 2016; DOI: 10.1016/j.ins.2015.10.023


Iyer R.R.,Teva Branded Pharmaceutical Products R and D Inc. | Pluciennik A.,Thomas Jefferson University | Napierala M.,University of Alabama at Birmingham | Napierala M.,Polish Academy of Sciences | Wells R.D.,Texas A&M University
Annual Review of Biochemistry | Year: 2015

DNA mismatch repair is a conserved antimutagenic pathway that maintains genomic stability through rectification of DNA replication errors and attenuation of chromosomal rearrangements. Paradoxically, mutagenic action of mismatch repair has been implicated as a cause of triplet repeat expansions that cause neurological diseases such as Huntington disease and myotonic dystrophy. This mutagenic process requires the mismatch recognition factor MutSβ and the MutLα (and/or possibly MutLγ) endonuclease, and is thought to be triggered by the transient formation of unusual DNA structures within the expanded triplet repeat element. This review summarizes the current knowledge of DNA mismatch repair involvement in triplet repeat expansion, which encompasses in vitro biochemical findings, cellular studies, and various in vivo transgenic animal model experiments. We present current mechanistic hypotheses regarding mismatch repair protein function in mediating triplet repeat expansions and discuss potential therapeutic approaches targeting the mismatch repair pathway. Copyright © 2015 by Annual Reviews. All rights reserved.


Prokop P.,Polish Academy of Sciences | Poreba G.J.,Silesian University of Technology
Land Degradation and Development | Year: 2012

Rapid increase in population and growing demand for agricultural products has generated changes in land use and upland farming systems and resulted in erosion and land degradation over large tracts of northeast India. The spatial variation of soil erosion rates was studied, in a small catchment under a modified form of shifting cultivation on the hilly Meghalaya Plateau, using the 137Cs technique. Soil erosion and deposition patterns are much influenced by land use. The estimated annual soil loss from cultivated fields ranged from 32 to 79Mgha-1y-1 and reached only 0·5Mgha-1y-1 from degraded grassland. Calculated soil erosion rates from cultivated fields exceed that which can be produced by weathering of new soil from parent materials. Observed intensification of agricultural production will lead to progressive conversion of cultivated fields into degraded grasslands and other changes to land use in the upper part of the Meghalaya Plateau. © 2012 John Wiley & Sons, Ltd.


Kedia H.,James Franck Institute | Bialynicki-Birula I.,Polish Academy of Sciences | Peralta-Salas D.,Institute Ciencias Matematicas | Irvine W.T.M.,James Franck Institute
Physical Review Letters | Year: 2013

We construct analytically, a new family of null solutions to Maxwell's equations in free space whose field lines encode all torus knots and links. The evolution of these null fields, analogous to a compressible flow along the Poynting vector that is shear free, preserves the topology of the knots and links. Our approach combines the construction of null fields with complex polynomials on S3. We examine and illustrate the geometry and evolution of the solutions, making manifest the structure of nested knotted tori filled by the field lines. © 2013 American Physical Society.


Kierzek E.,Polish Academy of Sciences | Malgowska M.,Polish Academy of Sciences | Lisowiec J.,Polish Academy of Sciences | Turner D.H.,University of Rochester | And 2 more authors.
Nucleic Acids Research | Year: 2014

Thermodynamic data are reported revealing that pseudouridine (Ψ) can stabilize RNA duplexes when replacing U and forming Ψ-A, Ψ-G, Ψ-U and Ψ-C pairs. Stabilization is dependent on type of base pair, position of Ψ within the RNA duplex, and type and orientation of adjacent Watson-Crick pairs. NMR spectra demonstrate that for internal Ψ-A, Ψ-G and Ψ-U pairs, the N3 imino proton is hydrogen bonded to the opposite strand nucleotide and the N1 imino proton may also be hydrogen bonded. CD spectra show that general A-helix structure is preserved, but there is some shifting of peaks and changing of intensities. Ψ has two hydrogen donors (N1 and N3 imino protons) and two hydrogen bond acceptors because the glycosidic bond is C-C rather than C-N as in uridine. This greater structural potential may allow Ψ to behave as a kind of structurally driven universal base because it can enhance stability relative to U when paired with A, G, U or C inside a double helix. These structural and thermodynamic properties may contribute to the biological functions of Ψ. © The Author(s) 2013.


Tomaszewska B.,Polish Academy of Sciences | Bodzek M.,Silesian University of Technology | Bodzek M.,Polish Academy of Sciences
Desalination | Year: 2013

The study assessed the potential of reverse osmosis with low-pressure BWRO membranes to reduce total dissolved solids (TDS) and enhance removal of boron and other microelements (such as iron, fluoride and arsenic), so making geothermal waters suitable for discharge into surface waters or reuse for drinking purposes. Preliminary treatment involved an iron removal system (a reduction in iron concentration from max ca. 4. mg/L to 0.013-0.021. mg/L, i.e. a reduction of 99%, was obtained) and ultrafiltration modules (the average SDI after pre-treatment was 2.4).The reverse osmosis system was equipped with spiral wound DOW FILMTEC BW30HR-440i polyamide thin-film composite membranes. To optimise boron removal the membrane separation performance was assessed in short and long-term tests at a semi-production scale (production of desalinated water at 1m3/h) over an eight-month period.It was found that the boron removal rate in acidic feedwater depended on the boron concentration. The highest removal rate of 56% was obtained in water with 2.5mgB/L, followed by 48% in water containing 8.98mgB/L and a very poor final result of 12% in 96.73mgB/L. High boron removal rates of 96 and 97% were obtained in water with pH 10 and 11 containing ca. 10mgB/L, regardless of the feedwater uptake ratio. Feedwaters with a high boron concentration of ca. 100mg/L and pH=10 yielded a low boron removal rate of 66%. Efficient and stable performance of the BWRO-membrane equipped desalination system was achieved with geothermal waters containing 7g/L TDS and a boron concentration of up to 10mg/L. Taking account of the low pressure applied in the reverse osmosis process (1.1MPa), a relatively high removal rate was obtained following the first stage of RO (at pH of 5±0.4): 96-97% with respect to conductivity, and 94% with respect to SiO2, 92% for fluoride and not less than 84% for arsenic. © 2012 Elsevier B.V.


Carinena J.F.,University of Zaragoza | De Lucas Araujo J.,Polish Academy of Sciences
Journal of Geometric Mechanics | Year: 2011

A superposition rule is a particular type of map that enables one to express the general solution of certain systems of first-order ordinary di erential equations, the so-called Lie systems, out of generic families of particular solutions and a set of constants. The first aim of this work is to propose various generalisations of this notion to second-order di erential equations. Next, several results on the existence of such generalisations are given and relations with the theories of Lie systems and quasi-Lie schemes are found. Finally, our methods are used to study second-order Riccati equations and other second-order di erential equations of mathematical and physical interest. © American Institute of Mathematical Sciences.


Sharma P.S.,Polish Academy of Sciences | D'Souza F.,University of North Texas | Kutner W.,Polish Academy of Sciences | Kutner W.,Cardinal Stefan Wyszynski University in Warsaw
TrAC - Trends in Analytical Chemistry | Year: 2012

Environmental and health safety requires thorough determination of hazardous compounds and drugs of abuse. In determinations of these analytes, traditional instrumental analytical techniques often suffer from tedious assay procedures. Biosensors are simpler to construct and faster in use, so they can better meet the analytical demands in determination of these biohazards. However, their stability and reproducibility when operating under harsh conditions are poor, so artificial recognition units have become attractive as replacements for natural receptors in sensing applications. Molecular imprinting is one of the most powerful tools for preparing materials that can bind analytes reversibly and selectively in the presence of their interferents. This review critically evaluates the development of chemical sensing of biohazards and drugs of abuse using the molecular-imprinting approach to recognition in combination with different ways of analytical signal transduction. We compile analytical parameters of the molecularly-imprinted receptors, identify difficulties in the determinations encountered and highlight proposed solutions to problems. © 2012 Elsevier Ltd.


Kierzek R.,Polish Academy of Sciences | Turner D.H.,University of Rochester | Kierzek E.,Polish Academy of Sciences
Nucleic Acids Research | Year: 2015

Oligonucleotide microarrays are widely used in various biological studies. In this review, application of oligonucleotide microarrays for identifying binding sites and probing structure of RNAs is described. Deep sequencing allows fast determination of DNA and RNA sequence. High-throughput methods for determination of secondary structures of RNAs have also been developed. Those methods, however, do not reveal binding sites for oligonucleotides. In contrast, microarrays directly determine binding sites while also providing structural insights. Microarray mapping can be used over a wide range of experimental conditions, including temperature, pH, various cations at different concentrations and the presence of other molecules. Moreover, it is possible to make universal microarrays suitable for investigations of many different RNAs, and readout of results is rapid. Thus, microarrays are used to provide insight into oligonucleotide sequences potentially able to interfere with biological function. Better understanding of structure-function relationships of RNA can be facilitated by using microarrays to find RNA regions capable to bind oligonucleotides. That information is extremely important to design optimal sequences for antisense oligonucleotides and siRNA because both bind to single-stranded regions of target RNAs. © 2015 The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.


Dietl T.,Polish Academy of Sciences | Dietl T.,University of Warsaw | Dietl T.,Tohoku University | Ohno H.,Tohoku University
Reviews of Modern Physics | Year: 2014

This review compiles results of experimental and theoretical studies on thin films and quantum structures of semiconductors with randomly distributed Mn ions, which exhibit spintronic functionalities associated with collective ferromagnetic spin ordering. Properties of p-type Mn-containing III-V as well as II-VI, IV-VI, V2-VI3, I-II-V, and elemental group IV semiconductors are described, paying particular attention to the most thoroughly investigated system (Ga,Mn)As that supports the hole-mediated ferromagnetic order up to 190 K for the net concentration of Mn spins below 10%. Multilayer structures showing efficient spin injection and spin-related magnetotransport properties as well as enabling magnetization manipulation by strain, light, electric fields, and spin currents are presented together with their impact on metal spintronics. The challenging interplay between magnetic and electronic properties in topologically trivial and nontrivial systems is described, emphasizing the entangled roles of disorder and correlation at the carrier localization boundary. Finally, the case of dilute magnetic insulators is considered, such as (Ga,Mn)N, where low-temperature spin ordering is driven by short-ranged superexchange that is ferromagnetic for certain charge states of magnetic impurities. © 2014 American Physical Society.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA-CA | Phase: ENV.2012.6.5-4 | Award Amount: 1.08M | Year: 2012

Air quality in Europe is still facing a continued wide-spread of exceedances, particularly regarding PM, NOx and O3. The 2008 Air Quality Directive requests Member States (MS) to design local and regional plans and assess their impacts on air quality and human health. MS have therefore developed and applied a wide range of modeling methods to cope with these obligations. Today, with the revision of the EU air quality policy pending, there is the need to consolidate and assess the research results in the field and to make them accessible to policy makers. This is the main aim of APPRAISAL project, split in the following objectives: -Undertake on overall review of the methodologies used in different countries, from the simple (scenario analysis) to the more comprehensive (cost-benefit, cost-effectiveness analysis). This would include evaluating top-down and bottom-up approaches to systematically analyze their strengths and weaknesses and to identify key areas to be addressed by further research. The result would be captured in a readily updatable, user friendly relational data base. -Design an integrated assessment (IA) modeling framework where existing components are efficiently inter-connected, produce guidelines describing the key components of best practices. A number of test cases will be explored to confirm the robustness of the guidelines in practice. -Communicate with key stake-holders and in particular to policy-makers the state-of-the-art scientific knowledge on emission abatement assessment. APPRAISAL includes 15 highly experienced groups working on both air quality and health impacts assessment. Partners come from all over Europe to guarantee the review process representativeness. A group of stakeholders will closely be connected to the Consortium to ensure a direct line of communication with key policy makers. APPRAISAL will contribute to improved knowledge on regional and local IA methodologies and will support the revision of EU air quality policies.


News Article | February 1, 2016
Site: phys.org

Scientometrics research is the science of evaluating scientific performance. Physics methods designed to predict growth based on a scale-free network have rarely been applied to this field. Now, scientists in Poland have developed an analytical method using a previously developed agent-based model to predict the h-index, probably the most popular citation-based scientific measurement, using bibliometric data. They are the very first to succeed in developing an exact formula to calculate the number of external citations and self-citations for each paper written by an author. These findings have just been published in the European Physics Journal B by Barbara Żogała-Siudem from the Systems Research Institute, Polish Academy of Sciences, Warsaw, and colleagues. It opens the door to applying this growth analysis to social network users or citations from different scientific fields. Knowing an author's overall number of papers and total number of citations helps compute an approximated value of their h-index, which was named after the American physicist J.E. Hirsch in 2005 and measures the overall number of a scientist's publications as well as their quality and number of citations. In this study, the authors relied on rate equations, a complex systems physics tool. To establish the equations governing the growth of citation networks, they incorporated a rule called the preferential attachment rule. Although this rule has been known for over 50 years, it remained unclear until now how and why such rules matter to the growth of the h-index. The explanation came from incorporating the rule into agent-based models representing citation networks, otherwise known as the Ionescu-Chopard (IC) model. This led to exact h-index predictions—just like with the IC model alone—and enabled the authors to explain some underlying bibliometric phenomena. For example, they showed that the h-index can be further investigated using the aggregation theory. Lastly, they verified their results with data from real authors as well as numerical simulations. Explore further: Report on citation statistics: Numbers with a number of problems More information: Barbara Żogała-Siudem et al. Agent-based model for the h-index – exact solution, The European Physical Journal B (2016). DOI: 10.1140/epjb/e2015-60757-1


News Article | October 13, 2016
Site: www.cemag.us

The advanced phase of acute kidney injury can be fatal in every one in two patients. Fortunately, now it will be possible to detect the disease in its initial stages, when treatment is still relatively simple and the prognosis good. The key to this health and life-saving manner of diagnosis is a new polymer, designed at the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw. The chemical heart of low-cost diagnostic tools capable of detecting the early stages of kidney disease may, in the near future, be a special polymer prepared by PhD student Zofia Iskierko under the supervision of Dr. Krzysztof Noworyta, in Professor Wlodzimierz Kutner's group at the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw. The polymer was designed and carefully constructed so as to particularly effectively entrap only one substance in its vicinity: lipocalin-2 (NGAL), a protein naturally occurring in human blood. For the clinician, an increase in the concentration of this compound in a patient is a valuable signal of still symptomless, but already developing, acute kidney injury. Work on the implementation of the polymer, funded by grant from the Polish National Centre for Science, was carried out in collaboration with the University of North Texas in Denton, the Warsaw Institute of Physics of the Academy of Sciences, and the International Institute of Molecular and Cell Biology. "We deal with the creation of polymer recognition films for chemosensors that detect various substances. These include biomarkers and other biologically important compounds, whose presence or changes in concentration in body fluids carry information about the health of the patient. Our latest polymer can selectively capture lipocalin-2, a protein biomarker for acute kidney injury," says Noworyta. Acute kidney injury, earlier known as acute renal failure, affects about three in a thousand people. However, on hospital wards the situation is much more serious: up to 40 percent of hospital patients may suffer from this disease. With early diagnosis the effects of acute kidney injury are reversible. The clear symptoms of the disease such as fatigue, vomiting or altered consciousness, however, only appear at an advanced stage of its development when possible complications become a serious threat to life (in the most advanced stage, the mortality rate reaches up to 50 percent). Kidney damage, which occurs in the late stages of the disease, may be permanent and require continued dialysis or even entire organ transplantation. "Before acute kidney injury develops, the concentration of lipocalin increases in patient's blood. So, we devised a polymer in whose structure there are molecular cavities that are a good fit for the shape and properties of the molecules of just this compound. The probability that any other protein will get caught in them is very, very small," explains Iskierko, the lead author of the publication in the journal ACS Applied Materials & Interfaces ("Molecularly Imprinted Polymer (MIP) Film with Improved Surface Area Developed by Using Metal-Organic Framework (MOF) for Sensitive Lipocalin (NGAL) Determination"). The new polymer was prepared by molecular imprinting. Molecules of lipocalin were first surrounded by appropriately selected (so called functional) monomers binding with the protein at specific locations characteristic only for itself. Then, a cross-linking monomer was introduced which combined with the functional one. Those monomers were later subjected to polymerization, after which the lipocalin was washed out of the resulting structure. Finally, a stable polymer film was obtained with molecular cavities matching lipocalin molecules both in terms of their local chemical features as well as their size and shape. "When lipocalin molecules in the test solution come into contact with a polymer formed in this manner, some of them have the chance to be deposited in the cavities. Proteins, however, are quite large and they are reluctant to migrate through the polymer network. Therefore, the structure of our polymer had to be artificially loosened enough to ensure the lipocalin molecules had the best access to the greatest number of cavities, but not excessively, so that the polymer film would not collapse," says Noworyta. The IPC PAS researchers obtained the required porosity, whilst retaining sufficient mechanical strength, by using MOF (metal-organic framework) inorganic-organic microporous materials. In terms of structure, MOF materials resemble three-dimensional lattices whose mesh sizes depend on the type of metal atoms and connecting ligands used. It was on this construction frame that the actual recognition film was fabricated. When the polymer had been immobilized, in the process of removing lipocalin molecules, the MOF skeleton - by this time redundant - was also destroyed. This treatment also resulted in an extension of the polymer surface, leading to an increase in cavities available for the protein molecules and ensuring better sensitivity of the chemosensor. The polymer mass increases after entrapping the lipocalin molecules. Therefore, if it were to be placed on a small piezoelectric oscillator, its easy-to-measure oscillation frequency would have to decrease. Another method of identifying the presence of lipocalin particles within the molecular cavities is to measure changes in the potential of the recognition film, which alters the current flowing in the processing field effect transistor component. Due to its simplicity and reliability, this latter solution would be particularly suitable for commercial chemosensors designed for mass production. "Our research is of a basic, laboratory nature. It is, however, still a long way from the preparation of a polymer capturing lipocalin to the mass production of low-cost detectors for the prevention and early treatment of disease," says Kutner. Niels Bohr, the great Danish quantum physicist, used to say that predicting was difficult, especially when it comes to the future. However, it seems reasonable to suppose that in the next decade devices detecting various biomarkers and warning early on of a threat to health will become an integral part of the ubiquitous smartphone. Diagnosis would then become as simple as testing blood sugar using today's glucose meters: it would suffice to connect a removable, simple chemosensor with an appropriately selected polymer recognition film to the smartphone, apply a little physiological fluid to it, and wait for the smartphone to display the result. Everyone would be able to carry out advanced medical diagnostics as often as they deemed appropriate. Source: Institute of Physical Chemistry of the Polish Academy of Sciences


HOUSTON--(BUSINESS WIRE)--Headline of release should read: PAS Presents at POWER-GEN International 2016 on ICS Cybersecurity and Operator Performance (instead of PAS Presents at POWER-GEN Europe 2016 on ICS Cybersecurity and Operator Performance) PAS PRESENTS AT POWER-GEN INTERNATIONAL 2016 ON ICS CYBERSECURITY AND OPERATOR PERFORMANCE PAS, Inc., the leading solution provider of process safety, cybersecurity, and asset reliability in the energy, power, and process industries, announced today that it will present at the POWER-GEN International, which takes place December 13 - 15, 2016, in Orlando, Florida. Bill Hollifield, Principal Consultant, will present Addressing the Common Misperceptions of High Performance HMI on Tuesday, December 13th, in the 1:30pm session of the Plant Performance 1 Track. David Zahn, CMO and GM of the Cybersecurity Business Unit, will present ICS Cybersecurity: You Cannot Secure What You Cannot See on Wednesday, December 14th, in the 1:30pm session of the Digital Power Plant Track. PAS will showcase its solutions in booth 4778. “We are excited to participate in POWER-GEN International 2016 both as speakers and an exhibitor,” said David Zahn. “POWER-GEN provides a valuable forum to learn about industry trends and challenges, evaluate the latest technologies, and share best practices.” PAS Cyber Integrity™ hardens security for the most vulnerable assets in a plant, the industrial control systems. Cyber Integrity works across all major proprietary and non-proprietary plant control systems providing automated asset inventory, configuration, and patch management capabilities as well as backup and recovery. The software automates internal and NERC-CIP regulatory compliance reporting while reducing associated efforts by up to 90 percent. PAS PowerGraphiX™, a high performance HMI™ solution for the power industry, is a collection of predesigned operator graphics and object libraries for coal fired, combined cycle, and super critical power plants. PAS is a leading provider of software solutions for process safety, cybersecurity, and asset reliability to the energy, process, and power industries worldwide. PAS solutions include industrial control system cybersecurity, automation asset management, IPL assurance, alarm management, high performance HMI, boundary management, and control loop performance optimization. PAS solutions are installed in over 1,100 facilities worldwide in more than 70 countries. PAS technology is used by five of the top 15 power companies in the world. For more information, visit www.pas.com. Connect with PAS on Twitter @PASGlobal or LinkedIn.


Pawlowski J.,University of Geneva | Holzmann M.,University of Geneva | Tyszka J.,Polish Academy of Sciences
Marine Micropaleontology | Year: 2013

The limitations of a traditional morphology-based classification of Foraminifera have been demonstrated by molecular phylogenetic studies for several years now. Despite the accumulation of molecular data, no alternative higher-level taxonomic system incorporating these data has been proposed yet. Here, we present a new supraordinal classification of Foraminifera based on an updated SSU rDNA phylogeny completed with the description of major morphological trends in the evolution of this group. According to the new system, multi-chambered orders are grouped in two new classes: Tubothalamea and Globothalamea. Naked and single-chambered Foraminifera possessing agglutinated or organic-walled tests are arranged into a paraphyletic assemblage of "monothalamids". The new system maintains some multi-chambered calcareous orders, such as Rotaliida, Miliolida, Robertinida and Spirillinida, although their definitions have been modified in some cases to include agglutinated taxa. The representatives of the planktonic order Globigerinida are tentatively included in the order Rotaliida. The agglutinated Textulariida are probably paraphyletic. The position of the order Lagenida is uncertain because reliable molecular data are only available for one species. The new classification system separates orders or families, which differ in basic chamber shapes, prevailing mode of coiling and distance between successive apertures. It appears that these features correspond better to the main evolutionary trends in Foraminifera than wall composition and structure, both used in traditional classification. © 2013 Elsevier B.V.


Rosspeintner A.,University of Geneva | Koch M.,University of Geneva | Angulo G.,Polish Academy of Sciences | Vauthey E.,University of Geneva
Journal of the American Chemical Society | Year: 2012

The effect of viscosity on the bimolecular electron transfer quenching of a series of coumarins by N,N-dimethylaniline was investigated using steady-state and time-resolved fluorescence spectroscopy. The data reveal that the static and transient stages of the quenching become dominant as viscosity increases. When extracting the quenching rate constants using a simple Stern-Volmer analysis, a decrease of the rate constant with increasing driving force is observed above ∼2 cP. However, this apparent Marcus inverted region, already reported several times with the same system in micelles and room temperature ionic liquids, totally vanishes when analyzing the data with a model accounting for the static and transient stages of the quenching. It appears that the apparent Marcus inverted region arises from the neglect of these quenching regimes together with the use of fluorophores with different excited-state lifetimes. © 2012 American Chemical Society.


Rosspeintner A.,University of Geneva | Angulo G.,Polish Academy of Sciences | Vauthey E.,University of Geneva
Journal of the American Chemical Society | Year: 2014

To access the intrinsic, diffusion free, rate constant of bimolecular photoinduced electron transfer reactions, fluorescence quenching experiments have been performed with 14 donor/acceptor pairs, covering a driving-force range going from 0.6 to 2.4 eV, using steady-state and femtosecond time-resolved emission, and applying a diffusion-reaction model that accounts for the static and transient stages of the quenching for the analysis. The intrinsic electron transfer rate constants are up to 2 orders of magnitude larger than the diffusion rate constant in acetonitrile. Above ∼1.5 eV, a slight decrease of the rate constant is observed, pointing to a much weaker Marcus inverted region than those reported for other types of electron transfer reactions, such as charge recombination. Despite this, the driving force dependence can be rationalized in terms of Marcus theory. © 2014 American Chemical Society.


Koch M.,University of Geneva | Rosspeintner A.,University of Geneva | Angulo G.,Polish Academy of Sciences | Vauthey E.,University of Geneva
Journal of the American Chemical Society | Year: 2012

The fluorescence quenching of 3-cyanoperylene upon electron transfer from N,N-dimethylaniline in three room-temperature ionic liquids (RTILs) and in binary solvent mixtures of identical viscosity has been investigated using steady-state and time-resolved fluorescence spectroscopy. This study was stimulated by previous reports of bimolecular electron transfer reactions faster by one or several orders of magnitude in RTILs than in conventional polar solvents. These conclusions were usually based on a comparison with data obtained in low-viscous organic solvents and extrapolated to higher viscosities and not by performing experiments at similar viscosities as those of the RTILs, which we show to be essential. Our results reveal that (i) the diffusive motion of solutes in both types of solvents is comparable, (ii) the intrinsic electron transfer step is controlled by the solvent dynamics in both cases, being slower in the RTILs than in the conventional organic solvent of similar viscosity, and (iii) the previously reported reaction rates much larger than the diffusion limit at low quencher concentration in RTILs originate from a neglect of the static and transient stages of the quenching, which are dominant in solvents as viscous as RTILs. © 2012 American Chemical Society.


Czechowski A.,Polish Academy of Sciences | Mann I.,Belgium Institute for Space Aeronomie | Mann I.,Osaka University
Astrophysical Journal | Year: 2010

We study the dynamics of nano dust grains in the region inward from 1AU. Assuming that the grains are created with the velocities close to Keplerian, we find that, despite the strong coupling to magnetic field, there is a population of trapped nano grains within about 0.2AU from the Sun. The nano dust grains produced outside of the trapped region are accelerated to high velocities, of the order of 300kms-1, provided that the charge to mass ratio is not much less than 10-5 e/m p. These values correspond to dust sizes equal or smaller than approximately 10nm. © 2010. The American Astronomical Society. All rights reserved.


Bujarski J.J.,Northern Illinois University | Bujarski J.J.,Polish Academy of Sciences
Frontiers in Plant Science | Year: 2013

RNA recombination is one of the driving forces of genetic variability in (+)-strand RNA viruses. Various types of RNA-RNA crossovers were described including crosses between the same or different viral RNAs or between viral and cellular RNAs. Likewise, a variety of molecular mechanisms are known to support RNA recombination, such as replicative events (based on internal or end-to-end replicase switchings) along with non-replicative joining among RNA fragments of viral and/or cellular origin. Such mechanisms as RNA decay or RNA interference are responsible for RNA fragmentation and trans-esterification reactions which are likely accountable for ligation of RNA fragments. Numerous host factors were found to affect the profiles of viral RNA recombinants and significant differences in recombination frequency were observed among various RNA viruses. Comparative analyses of viral sequences allowed for the development of evolutionary models in order to explain adaptive phenotypic changes and co-evolving sites. Many questions remain to be answered by forthcoming RNA recombination research. (1) How various factors modulate the ability of viral replicase to switch templates, (2) What is the intracellular location of RNA-RNA template switchings, (3) Mechanisms and factors responsible for non-replicative RNA recombination, (4) Mechanisms of integration of RNA viral sequences with cellular genomic DNA, and (5) What is the role of RNA splicing and ribozyme activity. From an evolutionary stand point, it is not known how RNA viruses parasitize new host species via recombination, nor is it obvious what the contribution of RNA recombination is among other RNA modification pathways. We do not understand why the frequency of RNA recombination varies so much among RNA viruses and the status of RNA recombination as a form of sex is not well documented. © 2013 Bujarski.


Kwapien J.,Polish Academy of Sciences | Drozdz S.,Polish Academy of Sciences | Drozdz S.,Cracow University of Technology
Physics Reports | Year: 2012

Typically, complex systems are natural or social systems which consist of a large number of nonlinearly interacting elements. These systems are open, they interchange information or mass with environment and constantly modify their internal structure and patterns of activity in the process of self-organization. As a result, they are flexible and easily adapt to variable external conditions. However, the most striking property of such systems is the existence of emergent phenomena which cannot be simply derived or predicted solely from the knowledge of the systems' structure and the interactions among their individual elements. This property points to the holistic approaches which require giving parallel descriptions of the same system on different levels of its organization. There is strong evidence-consolidated also in the present review-that different, even apparently disparate complex systems can have astonishingly similar characteristics both in their structure and in their behaviour. One can thus expect the existence of some common, universal laws that govern their properties. Physics methodology proves helpful in addressing many of the related issues. In this review, we advocate some of the computational methods which in our opinion are especially fruitful in extracting information on selected-but at the same time most representative-complex systems like human brain, financial markets and natural language, from the time series representing the observables associated with these systems. The properties we focus on comprise the collective effects and their coexistence with noise, long-range interactions, the interplay between determinism and flexibility in evolution, scale invariance, criticality, multifractality and hierarchical structure. The methods described either originate from "hard" physics-like the random matrix theory-and then were transmitted to other fields of science via the field of complex systems research, or they originated elsewhere but turned out to be very useful also in physics - like, for example, fractal geometry. Further methods discussed borrow from the formalism of complex networks, from the theory of critical phenomena and from nonextensive statistical mechanics. Each of these methods is helpful in analyses of specific aspects of complexity and all of them are mutually complementary. © 2012 Elsevier B.V.


Gutkin E.,Nicolaus Copernicus University | Gutkin E.,Polish Academy of Sciences
Journal of Mathematical Fluid Mechanics | Year: 2012

In a study of capillary floating, Finn (J Math Fluid Mech 11:443-458, 2009) described a procedure for determining cross-sections of non-circular, infinite convex cylinders that float horizontally on a liquid surface in every orientation with contact angle p/2. Finn's procedure yielded incomplete results for other contact angles; he raised the question as to whether an analogous construction would be feasible in that case. In the note, Finn (J Math Fluid Mech 11:464-465, 2009) pointed out a connection with an independent problem on billiard caustics citing the unpublished work (Gutkin in Proceedings of the Workshop on Dynamics and Related Questions, PennState University, 1993) of the present author. Here we present a solution of the billiard problem in full detail, thus settling Finn's question in a surprising way. In particular, we show that such floating cylinders exist if and only if the contact angle lies in a certain, explicitly described countably dense set. Moreover, for each element ? in this set we exhibit a family of convex, non-circular cylinders that float in every orientation with contact angle ?. Our discussion contains other material of independent interest for the billiard ball problem. © 2011 Springer Basel AG.


Jakobisiak M.,Medical University of Warsaw | Golab J.,Medical University of Warsaw | Golab J.,Polish Academy of Sciences | Lasek W.,Medical University of Warsaw
Cytokine and Growth Factor Reviews | Year: 2011

Interleukin 15 participates in the development of important immune antitumor mechanisms. It activates CD8+ T cells, natural killer (NK) cells, NK T cells, and can promote the formation of antitumor antibodies. IL-15 can also protect T effector cells from the action of T regulatory cells and reverse tolerance to tumor-associated antigens. In pre-clinical studies IL-15 has been found to demonstrate potentiated antitumor effects following pre-association with IL-15Rα, or when used in combination with chemotherapy, adoptive therapy, monoclonal antibodies, and tumor vaccines. Although a clinical trial based on application of IL-15 in tumor patients has already begun, it is important to be aware of its potential side effects, including induction of autoimmunity and promotion of proliferation, survival, and dissemination of some tumor cells. © 2011 Elsevier Ltd.


Garg A.D.,Catholic University of Leuven | Martin S.,Catholic University of Leuven | Golab J.,Medical University of Warsaw | Golab J.,Polish Academy of Sciences | Agostinis P.,Catholic University of Leuven
Cell Death and Differentiation | Year: 2014

Accumulating data indicates that following anti-cancer treatments, cancer cell death can be perceived as immunogenic or tolerogenic by the immune system. The former is made possible due to the ability of certain anti-cancer modalities to induce immunogenic cell death (ICD) that is associated with the emission of damage-associated molecular patterns (DAMPs), which assist in unlocking a sequence of events leading to the development of anti-tumour immunity. In response to ICD inducers, activation of endoplasmic reticulum (ER) stress has been identified to be indispensable to confer the immunogenic character of cancer cell death, due to its ability to coordinate the danger signalling pathways responsible for the trafficking of vital DAMPs and subsequent anti-cancer immune responses. However, in recent times, certain processes apart from ER stress have emerged (e.g., autophagy and possibly viral response-like signature), which have the ability to influence danger signalling. In this review, we discuss the molecular nature, emerging plasticity in the danger signalling mechanisms and immunological impact of known DAMPs in the context of immunogenic cancer cell death. We also discuss key effector mechanisms modulating the interface between dying cancer cells and the immune cells, which we believe are crucial for the therapeutic relevance of ICD in the context of human cancers, and also discuss the influence of experimental conditions and animal models on these. © 2014 Macmillan Publishers Limited All rights reserved.


Bieniasz L.K.,Polish Academy of Sciences | Bieniasz L.K.,Cracow University of Technology
Electrochimica Acta | Year: 2010

Considering modern trends of laboratory automation in electroanalysis, the development of adaptive methods for automatic simulation of electrochemical transient techniques such as cyclic voltammetry is a topical issue. One of the classical simulation approaches relies on formulating, and solving numerically, relevant integral equations. In former work of the present author an adaptive variant of the popular Huber method serving for this purpose has been proposed, and successfully tested on electrochemical examples of first kind Abel integral equations (IEs). The method has been recently extended to second kind Volterra integral equations with weakly singular kernels and linear and non-linear dependences between the unknowns and their integrals. In the present work the validity of the extended method, for electrochemical simulations, is tested on representative examples of such equations, occurring in the theory of cyclic voltammetry. The performance of the method is found satisfactory, although errors of the simulated transients may deviate from the prescribed error tolerance parameter, so that achieving a given target accuracy is less straightforward than it was for the voltammograms described by the first kind Abel equations. © 2009 Elsevier Ltd. All rights reserved.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA-SA | Phase: FP7-PEOPLE-2012-NIGHT | Award Amount: 193.08K | Year: 2012

The impossible becomes possible on one particular night of the year! On 28 September 2012, all persons participating in Malopolska Researchers Night 2012 will be able to pass through the door of the future to discover the incredible present and go on a breath-taking scientific trip through time and space. Malopolska Researchers Night 2012 will be held in four of the Regions cities/towns: Krakow, Tarnow, Nowy Sacz and Niepolomice. With their huge scientific potential, these centres put Malopolska at the forefront of regional innovation in Poland. Malopolska Researchers Night 2012 is targeted mainly at children and teenagers. We want to show them how fascinating the research work can be. In a fun atmosphere, we will attempt to overcome the traditional stereotype of the researcher as a person whose head is in the clouds and who has little touch with reality. During the Night everybody will have the chance to meet face to face with researchers and see for themselves what fascinating individuals they are: full of passion, having a variety of interests yet dedicated to their work and investing immense efforts in the advancement of science. In 2012, Malopolska Researchers Night will be organised on an unprecedented scale thanks to the involvement of 15 Partners and 24 supporting institutions. 41 locations in Malopolska will be available to the public. Around 80 workshops, 108 shows and demonstrations and over 50 lectures will be hosted by 36 faculties/departments. Researchers will provide tours of as many as 50 laboratories and 19 exhibitions. Nearly 30 competitions and games will await the youngest participants. There will also be a wide choice of accompanying events: 8 theatre and cabaret performances by researchers, a music concert and multimedia shows. Nearly 700 researchers, over 300 students and 50 students associations will take the public on this incredible scientific journey.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA-SA | Phase: FP7-PEOPLE-2011-NIGHT | Award Amount: 178.16K | Year: 2011

Malopolska Researchers Night 2011, an event hosted by the regions four cities and towns: Krakow, Tarnow, Nowy Sacz and Niepolomice. On this special Night you will be able to feel like Harry Potter on a journey to meet incredible researchers. On 23 September 2011 Malopolska will go science mad for the fifth year running! The fifth anniversary of Malopolska Researchers Night will not be the only reason to celebrate. The year 2011 will also mark the 500th anniversary of the arrival of the first guinea pig in Europe and the 100th anniversary of Marie Curies Nobel Prize in chemistry. This will be the only night of the year when researchers will turn into excellent actors, directors, musicians, guides to the nooks and crannies of research laboratories, contestants and, above all, incredibly fascinating individuals. Attractions will range from experiments with public participation through innovative demonstrations, experiments, do-it yourself workshops to fascinating discussions, shows, concerts and games. Everybody will find something interesting for themselves. The project attracts huge public interest in the region and beyond (ca. 3,500 participants in 2007, ca.15,000 in 2008, ca. 20,000 in 2009 and ca. 27,000 in 2010). Factors such as the experience of previous years of the project and effective and well-established partnerships within the region are helpful in preparing the event and making it get better and better, year by year. A total of 13 Partners and 22 other organisations will participate in the project As many as approx. 520 researchers will be running activities on the Night with the help of over 240 students. The event will take place in 33 locations throughout Malopolska. The programme of attractions will include 71 workshops, over 150 shows and demonstrations, nearly 30 competitions and games, nearly 50 lectures, 60 guided tours of laboratories, a theatre performance, 4 concerts, 2 cabaret performances and a chemistry musical.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA-SA | Phase: FP7-PEOPLE-2013-NIGHT | Award Amount: 178.52K | Year: 2013

In 2013, Malopolska Researchers Night will be organised for the seventh time. Malopolska Researchers Night 2013 will be organised on an unprecedented scale thanks to the involvement of 24 Partners (both consortium and non-consortium members) and 24 collaborating institutions. On 27 September 2013, all present and future lovers of science are invited to join researchers in the four regional towns and cities participating in the project, i.e. Krakow, Tarnow, Nowy Sacz and Niepolomice, and explore the secrets of the research profession or just have fun playing with science. A record number of ca. 700 researchers and ca. 500 students (a total of 1,300!) as well as over 60 students associations have offered to assist with the project. Apart from the Partners participating in previous years of the project, new institutions, faculties and departments have joined this years project. Attractions such as ca. 150 workshops, 180 shows and demonstrations, over 100 lectures and guided tours of nearly 60 laboratories will await those who visit one of the 42 locations participating in Malopolska Researchers Night 2013. Lovers of puzzles will have a choice of ca. 35 competitions and quizzes and children will be invited to ca. 25 games with researchers. Malopolska Researchers Night 2013 will offer an opportunity to demonstrate not only what researchers do at work but also what they do in their free time. There will be exhibitions, theatre plays featuring researchers as actors, meetings and discussions over a cup of coffee and a talk show with researchers. Given the wide and varied programme of attractions, the participation of new institutions and the lessons learned from the six previous years of the project (it attracted 46,000 people last year) it is estimated that over 55,000 people will participate in Malopolska Researchers Night 2013. A professionally prepared and intensive awareness campaign will reach nearly 3 million people with information about the event.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA-SA | Phase: FP7-PEOPLE-2009-NIGHT | Award Amount: 149.08K | Year: 2010

If you wish to accompany researchers on an exploration of the mysteries of the world, come to Malopolska on 24 September 2010! On this unique night Malopolska will once again go science mad. Adventures with researchers will take place in three cities of the region: Krakow, Tarnow and Nowy Sacz. Researchers Night will provide a chance to meet and interact with researchers not only in their natural habitat but also in unexpected situations and venues. On this once-in-a-year occasion researchers will take on different personas: those of excellent actors, brilliant directors, guides through the mysterious nooks and crannies of scientific laboratories, sports competitors and geniuses who know the answers to almost any question. The event will provide an excellent opportunity to challenge the stereotypes and promote the image of researchers as a colourful, attractive and creative community. By gaining an insight into the work of researchers, young people will be encouraged to consider a career in research as an alternative to the much-advertised professions in business, entertainment, politics or the media.


Grant
Agency: Cordis | Branch: FP7 | Program: CSA-SA | Phase: FP7-PEOPLE-2009-NIGHT | Award Amount: 114.81K | Year: 2009

Southern Poland will go science mad on 25 September 2009, the third such event in as many years. In Krakw, Tarnw and Nowy Scz, cities forming part of the Where the researchers work route, researchers will come out of the confines of their laboratories and lecture halls, in which they spend their days making discoveries and exploring the frontiers of knowledge, to show their other face. Researchers Night will provide a chance to meet and interact with researchers not only in their everyday work environment, but also in unexpected situations and venues. Researchers will, in their turn, have an opportunity to challenge stereotypes by casting themselves in entirely new roles: as theatre actors, film directors and many more. Participants in Researchers Night will become acquainted with the cutting edge of scientific discovery. This will be a unique opportunity to get in touch with true science by exploring places that are otherwise inaccessible to the public: laboratories and other research facilities. Everybody will be able to approach researchers with questions. The project is based on a formula of hands-on demonstrations, dazzling experiments, entertaining discussions, amusing plays and interesting workshops and is designed to ensure that there will be enough variety for everyone to find something interesting to do. Malopolska Researchers Night is becoming a regular fixture on the regions calendar of events. The previous years project attracted as many as 15,000 participants, providing us with experience to build on for future success. Malopolska Researchers Night 2009 will take place in Krakw Polands most beautiful city, a centre of science and the seat of the oldest university in Eastern Europe and in Tarnw and Nowy Scz, new but rapidly growing research centres in Malopolska Voivodeship.


Grant
Agency: Cordis | Branch: FP7 | Program: MC-IRG | Phase: PEOPLE-2007-4-3.IRG | Award Amount: 75.00K | Year: 2009

The purpose of this project is to understand the basic mechanisms of neural control of undulatory locomotion in C. elegans worms. This will be achieved by a combination of mathematical modeling, quantitative behavioral tracking, and molecular/cellular neurogenetic manipulations. C. elegans worms move by generating an oscillatory neuromuscular wave that alternates dorsal and ventral muscles and propagates along the body. The molecular, cellular, and network level mechanisms of this oscillatory spatio-temporal activity are virtually unknown. Their understanding may provide insight about the relationship between neuromuscular dynamics and how behavior is created in these extensively genetically studied animals, and might be relevant for more advanced animals with more complex nervous system. The project is conceptually composed of two parts. In the first part we want to investigate questions related to the mechanisms controlling body undulations and coordination. In the second part we want to study behavioral transitions between forward and backward motion. The experimental part of the project, composed of genetic and neural manipulations and quantitative behavioral tracking of worms, will be conducted at the California Institute of Technology in the molecular biology lab of Prof. Paul W. Sternberg. The theoretical part, composed of statistical analysis of the data and large-scale computer simulations of the neural network of C. elegans relevant for locomotion, will be conducted at host institution, i.e., in the IPPT PAN in Warsaw, mainly by the proposal coordinator.


Mege D.,CNRS Nantes Laboratory of Planetology and Geodynamics | Mege D.,Polish Academy of Sciences | Bourgeois O.,CNRS Nantes Laboratory of Planetology and Geodynamics
Earth and Planetary Science Letters | Year: 2011

Martian global climate models that account for evidence of past glaciations reported in tropical to mid-latitude regions of Mars predict accumulation of water ice in Valles Marineris during past periods of high obliquity. Observational evidence for such glaciations is given here. Topographic basement ridges of tectonic origin are common in Valles Marineris, and display sackung features, an assemblage of tectonic patterns that are diagnostic of deep-seated gravitational slope deformation. This deformation is most easily explained by paraglacial ridge failure subsequent to ridge wall debuttressing and decohesion following the retreat of glaciers. This interpretation is supported by extensive bibliographic analysis of sackung triggers on Earth, by morphological evidence of subglacial erosion of the lower parts of Valles Marineris wallslopes, of periglacial erosion of their upper parts and by the presence of various types of glacial landforms on the floors of Valles Marineris troughs. The age of these equatorial glaciations is found to be older than 1.4. Gy and younger than 3.5. Gy. © 2011 Elsevier B.V.


Colmenares J.C.,Polish Academy of Sciences | Luque R.,University of Cordoba, Spain
Chemical Society Reviews | Year: 2014

Heterogeneous photocatalysis has become a comprehensively studied area of research during the past three decades due to its practical interest in applications including water-air depollution, cancer therapy, sterilization, artificial photosynthesis (CO2 photoreduction), anti-fogging surfaces, heat transfer and heat dissipation, anticorrosion, lithography, photochromism, solar chemicals production and many others. The utilization of solar irradiation to supply energy or to initiate chemical reactions is already an established idea. Excited electron-hole pairs are generated upon light irradiation of a wide-band gap semiconductor which can be applied to solar cells to generate electricity or in chemical processes to create/degrade specific compounds. While the field of heterogeneous photocatalysis for pollutant abatement and mineralisation of contaminants has been extensively investigated, a new research avenue related to the selective valorisation of residues has recently emerged as a promising alternative to utilise solar light for the production of valuable chemicals and fuels. This tutorial review will focus on the potential and applications of solid photonanocatalysts for the selective transformation of biomass-derived substrates. This journal is © The Royal Society of Chemistry.


Malinowski M.,Polish Academy of Sciences | Operto S.,French National Center for Scientific Research | Ribodetti A.,French National Center for Scientific Research
Geophysical Journal International | Year: 2011

Here we assess the potential of the visco-acoustic frequency domain full-waveform inversion (FWI) to reconstructP-wave velocity (V P) andP-wave attenuation factor (Q) from surface onshore seismic data. First, we perform a sensitivity analysis of the FWI based upon a grid search analysis of the misfit function and several synthetic FWI examples using velocity andQmodels of increasing complexity. Subsequently, we applied both the acoustic and visco-acoustic FWI to real surface wide-aperture onshore seismic data from the Polish Basin, where a strong attenuation of the seismic data is observed. The sensitivity analysis of the visco-acoustic FWI suggests that the FWI can jointly reconstruct the velocity and the attenuation factor if the signature of the attenuation is sufficiently strong in the data. A synthetic example corresponding to a homogeneous background model with an inclusion shows a reliable reconstruction ofV PandQin the inclusion, whenQis as small as 90 and 50 in the background model and in the inclusion, respectively. A first application of acoustic FWI to real data shows that a heuristic normalization of the data with offset allows us to compensate for the effect of the attenuation in the data and reconstruct a reliable velocity model. Alternatively, we show that visco-acoustic FWI allows us to reconstruct jointly both a reliable velocity model and aQmodel from the true-amplitude data. We propose a pragmatical approach based upon seismic modelling and source wavelet estimation to infer the best starting homogeneousQmodel for visco-acoustic FWI. We find the source wavelet estimation quite sensitive to the quality of the velocity and attenuation models used for the estimation. For example, source-to-source wavelets are significantly more consistent when computed in the final FWI model than in the initial one. A good kinematic and amplitude match between the early-arriving phases of the real and time-domain synthetic seismograms computed in the final FWI model provides an additional evidence of the reliability of the final FWI model. We find the recovered velocity and attenuation models consistent with the expected lithology and stratigraphy in the study area. We link high-attenuation zones with the increased clay content and the presence of the mineralized fluids. © 2011 The Authors Geophysical Journal International © 2011 RAS.


Barnes E.,University of Maryland University College | Cywinski L.,Polish Academy of Sciences | Das Sarma S.,University of Maryland University College
Physical Review Letters | Year: 2012

We solve the long-standing central spin problem for a general set of inhomogeneous bath couplings and a large class of initial bath states. We compute the time evolution of the coherence of a central spin coupled to a spin bath by resumming all orders of the time-convolutionless master equation, thus avoiding the need to assume weak coupling to the bath. The fully quantum, non-Markovian solution is obtained in the large-bath limit and is valid up to a time scale set by the largest coupling constant. Our result captures the full decoherence of an electron spin qubit coupled to a nuclear spin bath in a GaAs quantum dot for experimentally relevant parameters. In addition, our solution is quite compact and can readily be used to make quantitative predictions for the decoherence process and to guide the design of nuclear state preparation protocols. © 2012 American Physical Society.


Fedriani J.M.,CSIC - Doñana Biological Station | Zywiec M.,Polish Academy of Sciences | Delibes M.,CSIC - Doñana Biological Station
Ecology | Year: 2012

The persistence of mutualisms despite the strong incidence of exploiters could be explained if exploiters deny one or more services (i.e., cheat) while eventually supplying some subtler but critical services. Pulp feeders usually ingest fruit reward without dispersing seeds and thus are considered to be mainly cheaters or thieves of seed-disperser mutualisms. By consuming the fruit pulp, however, they could release seeds from pulp inhibitory effect, enhancing germination and, potentially, subsequent seedling emergence, growth, survival, and thus local recruitment. We evaluated such a largely neglected hypothesis by considering the interaction between Pyrus bourgaeana and its pulp feeders. We experimentally showed that pericarp removal had a consistent strong positive effect on seed performance (e.g., lower rotting and higher germination percentages) and seedling fate (greater emergence, growth, and survival to two years old). Interestingly, these relatively large positive effects of depulpation on plant fitness persisted for a surprisingly long time. Though seedlings experienced higher mortality under fruiting conspecifics, the benefits of depulpation were not overridden by high propagule mortality beneath fruiting trees or in adverse microhabitats after two years of monitoring. Specifically, the cumulative probability of establishment for depulped seeds was 4-25 times higher than for seeds in whole ripe fruits. Thus, under some circumstances, pulp feeders can provide essential services to endozoochorous plants. Our study contributes to clarifying the apparent paradox of plant-frugivore mutualisms that persist in the face of exploitation by pulp feeders. Because "thieves" and "mutualists" refer to the extremes of a complex continuum, and because organisms displaying concurrent cheating and honest behaviors during different host stages are likely prevalent, the persistent language of mutualists vs. thieves, cheaters, or exploiters might be misleading. © 2012 by the Ecological Society of America.


Rams M.,Polish Academy of Sciences | Simon K.,Budapest University of Technology and Economics
Journal of Statistical Physics | Year: 2014

Fractal percolation or Mandelbrot percolation is one of the most well studied families of random fractals. In this paper we study some of the geometric measure theoretical properties (dimension of projections and structure of slices) of these random sets. Although random, the geometry of those sets is quite regular. Our results imply that, denoting by E ⊂ ℝ2 a typical realization of the fractal percolation on the plane, dimH E < 1 then for all lines ℓ the orthogonal projection E ℓ of E to ℓ has the same Hausdorff dimension as E, dimH E > 1 then for any smooth real valued function f which is strictly increasing in both coordinates, the image f(E) contains an interval. The second statement is quite interesting considering the fact that E is almost surely a Cantor set (a random dust) for a large part of the parameter domain, see Chayes et al. (Probab. Theory Relat. Fields, 77(3):307-324, 1988). Finally, we solve a related problem about the existence of an interval in the algebraic sum of d≥2 one-dimensional fractal percolations. © 2013 Springer Science+Business Media New York.


Jakubowski H.,International Center for Public Health | Jakubowski H.,University of Life Sciences in Poznań | Jakubowski H.,Polish Academy of Sciences
Wiley Interdisciplinary Reviews: RNA | Year: 2012

Faithful translation of the genetic code during protein synthesis is fundamental to the growth, development, and function of living organisms. Aminoacyl-tRNA synthetases (AARSs), which define the genetic code by correctly pairing amino acids with their cognate tRNAs, are responsible for 'quality control' in the flow of information from a gene to a protein. When differences in binding energies of amino acids to an AARS are inadequate, editing is used to achieve high selectivity. Editing occurs at the synthetic active site by hydrolysis of noncognate aminoacyl-adenylates (pretransfer editing) and at a dedicated editing site located in a separate domain by deacylation of mischarged aminoacyl-tRNA (posttransfer editing). Access of nonprotein amino acids, such as homocysteine or ornithine, to the genetic code is prevented by the editing function of AARSs, which functionally partitions amino acids present in living cells into protein and nonprotein amino acids. Continuous editing is part of the tRNA aminoacylation process in living organisms from bacteria to human beings. Preventing mistranslation by the clearance of misactivated amino acids is crucial to cellular homeostasis and has a role in etiology of disease. Although there is a strong selective pressure to minimize mistranslation, some organisms possess error-prone AARSs that cause mistranslation. Elevated levels of mistranslation and the synthesis of statistical proteins can be beneficial for pathogens by increasing phenotypic variation essential for the evasion of host defenses. © 2011 John Wiley & Sons, Ltd.


Moskal-del Hoyo M.,University of Valencia | Moskal-del Hoyo M.,Polish Academy of Sciences
Review of Palaeobotany and Palynology | Year: 2013

Charcoal remains found in five archaeological sites provided an important source of information about the woody vegetation that developed during the Atlantic period in eastern Hungary. The results are presented jointly since all sites are located in very similar habitats, they reflect Neolithic cultures and present comparable floral compositions. The reconstruction of past forest communities from the Great Hungarian Plain in the Atlantic period is based on pollen analysis and new anthracological data offer significant complementary information to the established pollen sequences. These data were obtained from more than 5000 charcoal fragments in which 28 taxa were identified. The main contribution of the study is the reconstruction of specific types of forests that covered the area of the floodplains and the adjacent loess-mantled elevated islands. These environmental conditions were selected by the first Neolithic settlers of the region, due to the great diversity of flora and fauna along with rich soils and good water supply. The charcoal assemblages indicated that in the vicinity of the settlements, steppe oak woods and alluvial forests predominated. They were mainly composed of Quercus, Ulmus, Cornus and Fraxinus. © 2013 Elsevier B.V.


Bonanni A.,Johannes Kepler University | Dietl T.,Polish Academy of Sciences | Dietl T.,University of Warsaw
Chemical Society Reviews | Year: 2010

The comprehensive search for multifunctional materials has resulted in the discovery of semiconductors and oxides showing ferromagnetic features persisting to room temperature. In this tutorial review the methods of synthesis of these materials, as well as the application of element-specific nano-analytic tools, particularly involving synchrotron radiation and electron microscopy, are described and shown to reveal the presence of nano-scale phase separations. Various means to control the aggregation of magnetic cations are discussed together with the mechanisms accounting for ferromagnetism of either condensed or diluted magnetic semiconductors. Finally, the question of whether high temperature ferromagnetism is possible in semiconductors not containing magnetic ions is touched upon. © 2010 The Royal Society of Chemistry.


Grant
Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: SPA.2012.2.1-01 | Award Amount: 2.64M | Year: 2013

Black holes provide a crucial link between Einsteins theory of gravity and real cosmic objects which astronomers can observe and study in the Universe. This project is oriented towards legacy of the cornerstone XMM-Newton X-ray satellite mission of European Space Agency (ESA) in synergy with relevant data in other spectral domains that are covered by ground-based infrared and radio interferometric techniques at European Southern Observatory (ESO) and elsewhere. Information in different wavelengths will be gathered and explored in order to understand radiation processes in places of strong gravity, near black holes. We will address outstanding questions of determining the black hole spin, measuring the location of the accretion disc inner rim, and revealing connections between inflows and outflows in these objects. To this end we will analyze and interpret multi-wavelength spectral and fast timing information on accreting black holes in compact binaries, in cores of active galactic nuclei, as well as other galaxies exhibiting low level of activity due to intermittent supply of gas from the cosmic environment or by switching to a radiatively inefficient regime. We will include valuable data from archives and complement them by performing new observations where needed. Our main objective is to use and enhance computational tools that the participating groups have been developing over two decades, and to join our effort in a dedicated program of data analysis and science interpretation of the most bizarre cosmic objects. We will rely on unprecedented combination of sensitivity and energy resolution of current X-ray missions of ESA, together with wide spectral coverage by ground-based observatories in ESO and elsewhere. The developed techniques will be highly relevant in the context of new missions. We will make our tools available to the entire scientific community. The research team includes experts from 7 leading research institutes and universities.


News Article | November 2, 2016
Site: www.washingtonpost.com

Last week came the latest grim news about the Great Barrier Reef: In its remote and treasured northern section, coral death appears to be extensive in the wake of an extreme ocean heat event in March, followed by subsequent severe coral bleaching. It’s just the latest evidence that a changing climate is driving a wedge between two organisms that have managed to live together for eons in “one of the most successful modes of life that we know,” explains Kim Cobb, a coral reefs expert and climate scientist at Georgia Tech University. Those two organisms are corals and the photosynthetic algae, or zooxanthellae, that live inside their cells, and provide the corals with energy. The problem is that when ocean waters get too hot, coral “bleaching” occurs, and the corals banish the algae from their system, turning white. In this condition, starved of what it takes to survive, they can only last so long. Now, a new study in Science Advances gives the full context. In it, Katarzyna Frankowiak and Jarosław Stolarski of the Polish Academy of Sciences and a group of colleagues at institutions in Poland, the U.S., Brazil, and Switzerland studied the fossils of extremely ancient corals in order to try to determine precisely how far back in time this original symbiosis between coral and algae came to exist. That inquiry took the scientists all the way back to the Tethys Ocean, an ancient body of water that existed during the Triassic Period, between 252 and 201 million years ago, when the continents were in vastly different alignments than where they are today. Fossils from that sea still exist in Turkey, including some well preserved specimens of corals that researchers believed proliferated during this era, despite the poor quality of the waters in which they lived. “Even if the corals evolved much earlier, then really something strange and dramatic happened in the Triassic that caused the sort of boom of reef evolution,” said Stolarski. “It’s a situation that, something highly advantageous to these corals happened, they start to proliferate, and we think this is because of the symbiosis,” he continued. Extremely high-powered analyses of the composition of these coral skeletons, with a focus on the different isotopes of carbon, nitrogen, oxygen of which they’re composed, revealed that roughly 212-million-year-old corals living in this time period had indeed already achieved symbiosis with photosynthetic algae, which lived inside of their own bodies. Apparently, the symbiosis helped the corals thrive despite the murky and nutrient poor waters in which they lived, since after all, all it takes for photosynthesis is light, water, and carbon dioxide. “If we have the poor nutrient water, then the only way that the animal, the coral animal may survive, is to be symbiotic,” said Stolarski. That development, in turn, launched corals and their algal partners forward through time, a cooperation for the ages. And although there were many changes over the intervening several hundred million years, and although the symbiosis may have subsequently re-evolved or re-developed multiple times, we still find algae living inside of coral today. Granted, it’s not as if it was always smooth sailing. There were warm periods before the present one, for instance — but the symbiosis persisted. “The fact that together they have weathered off-scale warming and acidification events like the Paleocene-Eocene Thermal Maximum [55 million  years ago], when much of the world’s reef systems were wiped out, is a testament to the resilience of this model,” said Georgia Tech’s Cobb in a comment on the new study. However, Stolarski explained that the worrying difference in the present is not that oceans are warmer than they have ever been in the last 200 million years, but rather, that human driven climate change is happening far more rapidly than past climate changes in Earth’s history. “The problem of course is that if the symbiosis is broken, which happens in modern oceans, because of the temperature and stress, then the corals usually die because they do not have the nutrients that the algae are providing,” said Stolarski. “The speed of the changes, and especially the temperature changes of the oceans, are quite rapid, and really, the issue is whether globally speaking, the corals will be able to survive this.” Granted, Stolarski thinks that some of them can survive — even though there could be very big losses, as at the Great Barrier Reef. Cobb, too, argues that corals remain quite diverse and there will still be survivors of the latest global bleaching event, and perhaps of all of global warming. “I am reminded of the few corals that survived a temperature-related mortality event that killed up to 85% of the corals at my study site, Christmas Island,” she wrote by email. “These hardy corals will seed the recovery of this reef in the near-term, and their descendants may seed the global recovery of coral reefs once temperatures and atmospheric carbon dioxide levels stabilize.” Thomas Lovejoy, a prominent ecologist at George Mason University, told the Post earlier this year — at the peak of the global coral bleaching event — that the “single-species interaction” between coral and algae is a central part of the vulnerability of reefs. “We can do all the modeling we want, climate modeling, and vegetation modeling, and it’s never going to pick up these sensitivities that come down to in many instances, just a relationship between one or two species, or two or three species,” Lovejoy added Wednesday. “So whatever the models are telling you, they’re not sensitive enough to actually predict the kinds of things we’re seeing with corals. And the consequence of that, you just have to think even more carefully and conservatively.” “Some may survive, some may rebuild, but entire ecosystems are collapsing in the meantime,” said Lovejoy of coral reefs. But others are less pessimistic. “The new study is a powerful testament to the staying power of one of the most successful partnerships on our planet – one that has been honed and refined through repeated planetary-scale crises,” Cobb concluded. “There is no doubt that climate change will profoundly reshape global reefs over the next 100 years, but once the dust settles on our planetary-scale experiment, corals will likely flourish once more.”


News Article | December 8, 2016
Site: phys.org

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was highlighted again as the Royal Swedish Academy of Sciences in Stockholm awarded this year's Nobel Prize in Physics to three British scientists for their research of so-called topological phase transitions and topological phases of matter. Topological insulators are also being studied at the Departments for Experimental Physics II and Theoretical Physics I of the University of Würzburg. However, they focus on a special version of insulators called topological crystalline insulators (TCI). In cooperation with the Polish Academy of Sciences in Warsaw and the University of Zurich, Würzburg physicists have now achieved a major breakthrough. They were able to detect new electronic states of matter in these insulators. The results of their work are published in the latest issue of Science. The central result: When crystalline materials are split, small atomically flat terraces emerge at the split off surfaces which are separated from each other by step edges. Inside these structures, conductive channels for electrical currents form which are extremely narrow at just about 10 nm and surprisingly robust against external disturbance. Electrons travel on these conductive channels with different spin in opposite directions - similar to a motorway with separate lanes for the two directions. This effect makes the materials interesting for technological applications in future electronic components such as ultra-fast and energy-efficient computers. "TCIs are relatively simple to produce and they are already different from conventional materials because of their special crystalline structure," Dr. Paolo Sessi explains the background of the recently published paper. Sessi is a research fellow at the Department of Experimental Physics II and the lead author of the study. Moreover, these materials owe their special quality to their electronic properties: In topological materials, the direction of spin determines the direction in which the electrons travel. Simply put, the "spin" can be interpreted as a magnetic dipole that can point in two directions ("up" and "down"). Accordingly, up-spin electrons in TCIs move in one and down-spin electrons in the other direction. It's all about the number of atomic layers "But previously scientists didn't know how to produce the conductive channels required to this end," says Professor Matthias Bode, Head of the Department for Experimental Physics II and co-author of the study. It was chance that now got the researchers on the right track: They discovered that very narrow conductive channels occur naturally when splitting lead tin selenide (PbSnSe), a crystalline insulator. Step edges on the fragments' surfaces cause this phenomenon. They can be imaged using a high-resolution scanning tunnelling microscopy, or more precisely, the height of the corresponding step edges. "Edges that bridge an even number of atomic layers are totally inconspicuous. But if the edges span an odd number of atomic layers, a small area about 10 nm in width is created that has the electronic conductive channels properties we were looking for," Sessi explains. Pattern breaks off at the edge Supported by their colleagues from the Department of Theoretical Physics I and the University of Zurich, the experimental physicists were able to shed light on the origin of these new electronic states. To understand the principle, a little spatial sense is required: "The crystalline structure causes a layout of the atoms where the different elements alternate like the black and white squares on a chessboard," Matthias Bode explains. This alternating black-and-white pattern applies to both squares which are adjacent and squares situated below and on top one another. So if the crack of this crystal runs through different atomic layers, more than one edge is created there. Seen from above, white squares may also abut to other white squares along this edge and black squares to other black squares - or identical atoms to identical atoms. However, this only works if an odd number of atomic layers is responsible for the difference in height of the two surfaces. "Calculations show that this offset at the surface is actually causative of these novel electronic states," says Paolo Sessi. Furthermore, they prove that the phenomenon of the spin-dependent conductive channels, which is characteristic of topological materials, occurs here as well. According to the scientists, this property in particular makes the discovery relevant for potential applications, because such conductive channels cause low conduction loss on the one hand and can be used directly to transmit and process information in the field of spintronics on the other. However, several questions need to be answered and challenges to be overcome before this will become reality. For instance, the scientists are not yet sure over which distances the currents in the newly discovered conductive channels can be transported. Also, in order to be implemented in circuits, methods would have to be developed that allow creating step edges of a defined height along specified directions. Explore further: Realization of a novel material that can conduct magnetic waves on its edge, but not within its bulk More information: "Robust spin-polarized midgap states at step edges of topological crystalline insulators", Science, science.sciencemag.org/cgi/doi/10.1126/science.xaah6233


News Article | December 8, 2016
Site: www.eurekalert.org

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science. Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was highlighted again as the Royal Swedish Academy of Sciences in Stockholm awarded this year's Nobel Prize in Physics to three British scientists for their research of so-called topological phase transitions and topological phases of matter. Topological insulators are also being studied at the Departments for Experimental Physics II and Theoretical Physics I of the University of Würzburg. However, they focus on a special version of insulators called topological crystalline insulators (TCI). In cooperation with the Polish Academy of Sciences in Warsaw and the University of Zurich, Würzburg physicists have now achieved a major breakthrough. They were able to detect new electronic states of matter in these insulators. The results of their work are published in the latest issue of Science. The central result: When crystalline materials are split, small atomically flat terraces emerge at the split off surfaces which are separated from each other by step edges. Inside these structures, conductive channels for electrical currents form which are extremely narrow at just about 10 nm and surprisingly robust against external disturbance. Electrons travel on these conductive channels with different spin in opposite directions - similar to a motorway with separate lanes for the two directions. This effect makes the materials interesting for technological applications in future electronic components such as ultra-fast and energy-efficient computers. "TCIs are relatively simple to produce and they are already different from conventional materials because of their special crystalline structure," Dr. Paolo Sessi explains the background of the recently published paper. Sessi is a research fellow at the Department of Experimental Physics II and the lead author of the study. Moreover, these materials owe their special quality to their electronic properties: In topological materials, the direction of spin determines the direction in which the electrons travel. Simply put, the "spin" can be interpreted as a magnetic dipole that can point in two directions ("up" and "down"). Accordingly, up-spin electrons in TCIs move in one and down-spin electrons in the other direction. "But previously scientists didn't know how to produce the conductive channels required to this end," says Professor Matthias Bode, Head of the Department for Experimental Physics II and co-author of the study. It was chance that now got the researchers on the right track: They discovered that very narrow conductive channels occur naturally when splitting lead tin selenide (PbSnSe), a crystalline insulator. Step edges on the fragments' surfaces cause this phenomenon. They can be imaged using a high-resolution scanning tunnelling microscopy, or more precisely, the height of the corresponding step edges. "Edges that bridge an even number of atomic layers are totally inconspicuous. But if the edges span an odd number of atomic layers, a small area about 10 nm in width is created that has the electronic conductive channels properties we were looking for," Sessi explains. Supported by their colleagues from the Department of Theoretical Physics I and the University of Zurich, the experimental physicists were able to shed light on the origin of these new electronic states. To understand the principle, a little spatial sense is required: "The crystalline structure causes a layout of the atoms where the different elements alternate like the black and white squares on a chessboard," Matthias Bode explains. This alternating black-and-white pattern applies to both squares which are adjacent and squares situated below and on top one another. So if the crack of this crystal runs through different atomic layers, more than one edge is created there. Seen from above, white squares may also abut to other white squares along this edge and black squares to other black squares - or identical atoms to identical atoms. However, this only works if an odd number of atomic layers is responsible for the difference in height of the two surfaces. "Calculations show that this offset at the surface is actually causative of these novel electronic states," says Paolo Sessi. Furthermore, they prove that the phenomenon of the spin-dependent conductive channels, which is characteristic of topological materials, occurs here as well. According to the scientists, this property in particular makes the discovery relevant for potential applications, because such conductive channels cause low conduction loss on the one hand and can be used directly to transmit and process information in the field of spintronics on the other. However, several questions need to be answered and challenges to be overcome before this will become reality. For instance, the scientists are not yet sure over which distances the currents in the newly discovered conductive channels can be transported. Also, in order to be implemented in circuits, methods would have to be developed that allow creating step edges of a defined height along specified directions.


News Article | December 20, 2016
Site: www.materialstoday.com

Physicists at the University of Würzburg in Germany have made an astonishing discovery about the structure of a specific type of topological insulator, which they have reported in a paper in Science. Topological insulators, which conduct electricity at their surface but not within their bulk, are currently a hot topic in physics. Only a few weeks ago, their importance was highlighted when the Royal Swedish Academy of Sciences in Stockholm awarded this year's Nobel Prize in Physics to three British scientists for their research into so-called topological phase transitions and topological phases of matter. Topological insulators are also being studied at the departments for Experimental Physics II and Theoretical Physics I of the University of Würzburg, but the focus here is on a special type of insulator called topological crystalline insulators (TCI). In cooperation with researchers at the Polish Academy of Sciences in Warsaw and the University of Zurich in Switzerland, Würzburg physicists have now achieved a major breakthrough by detecting new electronic states of matter in these insulators. "TCIs are relatively simple to produce and they are already different from conventional materials because of their special crystalline structure," says Paolo Sessi, a research fellow at the Department of Experimental Physics II and lead author of the paper. In topological materials, the direction in which the electrons travel is determined by their spin: simply put, the ‘spin’ can be interpreted as a magnetic dipole that can point in two directions (‘up’ and ‘down’). Up-spin electrons in TCIs move in one direction and down-spin electrons in the other. "But previously scientists didn't know how to produce the conductive channels required to this end," says Matthias Bode, head of the Department for Experimental Physics II and co-author of the paper. By chance, Bode and his colleagues discovered that very narrow conductive channels occur naturally when splitting lead tin selenide (PbSnSe), a crystalline insulator. This happens because small, atomically-flat terraces emerge at the split, separated from each other by step edges. The conductive channels can then form within these step edges, depending on their precise height; these channels, which can be imaged using a high-resolution scanning tunneling microscopy, are extremely narrow, at around 10 nm, and surprisingly robust against external disturbance. "Edges that bridge an even number of atomic layers are totally inconspicuous, " explains Sessi. "But if the edges span an odd number of atomic layers, a small area about 10nm in width is created that has the electronic conductive channel properties we were looking for." Supported by their colleagues from the Department of Theoretical Physics I and the University of Zurich, the experimental physicists were able to shed light on the origin of these new electronic states. "The crystalline structure causes a layout of the atoms where the different elements alternate like the black and white squares on a chessboard," Bode says. This alternating black-and-white pattern applies to both squares that are adjacent to each other and squares that are on top of each other. This means that if the split in the crystal runs through different atomic layers, more than one edge is created. Seen from above, white squares may abut other white squares along this edge and black squares to other black squares – or identical atoms to identical atoms. This only works, however, if an odd number of atomic layers is responsible for the difference in height between the two surfaces. "Calculations show that this offset at the surface is actually causative of these novel electronic states," says Sessi. Furthermore, the calculations prove that the phenomenon of the spin-dependent conductive channels, which is characteristic of topological materials, occurs here as well. According to the scientists, these channels could prove of use in many applications, including ultra-fast and energy-efficient computers, because they cause low conduction loss and can be used directly to transmit and process information in the field of spintronics. However, several questions need to be answered and challenges overcome before this will become reality. For instance, the scientists are not yet sure over what kind of distance currents can be transported in the newly-discovered conductive channels. Also, in order for the channels to be implemented in circuits, methods would have to be developed that allow step edges of a defined height to be created along specified directions. This story is adapted from material from the University of Würzburg, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.


News Article | December 12, 2016
Site: www.nanotech-now.com

Abstract: Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science. Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was highlighted again as the Royal Swedish Academy of Sciences in Stockholm awarded this year's Nobel Prize in Physics to three British scientists for their research of so-called topological phase transitions and topological phases of matter. Topological insulators are also being studied at the Departments for Experimental Physics II and Theoretical Physics I of the University of Würzburg. However, they focus on a special version of insulators called topological crystalline insulators (TCI). In cooperation with the Polish Academy of Sciences in Warsaw and the University of Zurich, Würzburg physicists have now achieved a major breakthrough. They were able to detect new electronic states of matter in these insulators. The results of their work are published in the latest issue of Science. Step edges direct electrons The central result: When crystalline materials are split, small atomically flat terraces emerge at the split off surfaces which are separated from each other by step edges. Inside these structures, conductive channels for electrical currents form which are extremely narrow at just about 10 nm and surprisingly robust against external disturbance. Electrons travel on these conductive channels with different spin in opposite directions - similar to a motorway with separate lanes for the two directions. This effect makes the materials interesting for technological applications in future electronic components such as ultra-fast and energy-efficient computers. "TCIs are relatively simple to produce and they are already different from conventional materials because of their special crystalline structure," Dr. Paolo Sessi explains the background of the recently published paper. Sessi is a research fellow at the Department of Experimental Physics II and the lead author of the study. Moreover, these materials owe their special quality to their electronic properties: In topological materials, the direction of spin determines the direction in which the electrons travel. Simply put, the "spin" can be interpreted as a magnetic dipole that can point in two directions ("up" and "down"). Accordingly, up-spin electrons in TCIs move in one and down-spin electrons in the other direction. It's all about the number of atomic layers "But previously scientists didn't know how to produce the conductive channels required to this end," says Professor Matthias Bode, Head of the Department for Experimental Physics II and co-author of the study. It was chance that now got the researchers on the right track: They discovered that very narrow conductive channels occur naturally when splitting lead tin selenide (PbSnSe), a crystalline insulator. Step edges on the fragments' surfaces cause this phenomenon. They can be imaged using a high-resolution scanning tunnelling microscopy, or more precisely, the height of the corresponding step edges. "Edges that bridge an even number of atomic layers are totally inconspicuous. But if the edges span an odd number of atomic layers, a small area about 10 nm in width is created that has the electronic conductive channels properties we were looking for," Sessi explains. Pattern breaks off at the edge Supported by their colleagues from the Department of Theoretical Physics I and the University of Zurich, the experimental physicists were able to shed light on the origin of these new electronic states. To understand the principle, a little spatial sense is required: "The crystalline structure causes a layout of the atoms where the different elements alternate like the black and white squares on a chessboard," Matthias Bode explains. This alternating black-and-white pattern applies to both squares which are adjacent and squares situated below and on top one another. So if the crack of this crystal runs through different atomic layers, more than one edge is created there. Seen from above, white squares may also abut to other white squares along this edge and black squares to other black squares - or identical atoms to identical atoms. However, this only works if an odd number of atomic layers is responsible for the difference in height of the two surfaces. Backed by calculations "Calculations show that this offset at the surface is actually causative of these novel electronic states," says Paolo Sessi. Furthermore, they prove that the phenomenon of the spin-dependent conductive channels, which is characteristic of topological materials, occurs here as well. According to the scientists, this property in particular makes the discovery relevant for potential applications, because such conductive channels cause low conduction loss on the one hand and can be used directly to transmit and process information in the field of spintronics on the other. However, several questions need to be answered and challenges to be overcome before this will become reality. For instance, the scientists are not yet sure over which distances the currents in the newly discovered conductive channels can be transported. Also, in order to be implemented in circuits, methods would have to be developed that allow creating step edges of a defined height along specified directions. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


Cieplak M.,Polish Academy of Sciences | Robbins M.O.,Johns Hopkins University
Journal of Chemical Physics | Year: 2010

A molecular-level model is used to study the mechanical response of empty cowpea chlorotic mottle virus (CCMV) and cowpea mosaic virus (CPMV) capsids. The model is based on the native structure of the proteins that constitute the capsids and is described in terms of the Cα atoms. Nanoindentation by a large tip is modeled as compression between parallel plates. Plots of the compressive force versus plate separation for CCMV are qualitatively consistent with continuum models and experiments, showing an elastic region followed by an irreversible drop in force. The mechanical response of CPMV has not been studied, but the molecular model predicts an order of magnitude higher stiffness and a much shorter elastic region than for CCMV. These large changes result from small structural changes that increase the number of bonds by only 30% and would be difficult to capture in continuum models. Direct comparison of local deformations in continuum and molecular models of CCMV shows that the molecular model undergoes a gradual symmetry breaking rotation and accommodates more strain near the walls than the continuum model. The irreversible drop in force at small separations is associated with rupturing nearly all of the bonds between capsid proteins in the molecular model, while a buckling transition is observed in continuum models. © 2010 American Institute of Physics.


Opallo M.,Polish Academy of Sciences | Opallo M.,Cardinal Stefan Wyszynski University in Warsaw | Lesniewski A.,Polish Academy of Sciences
Journal of Electroanalytical Chemistry | Year: 2011

Since 2000, ionic liquids are applied for electrode modification. Until the middle of 2010, almost 300 papers about ionic liquid-modified electrodes were published and they are reviewed here. Hydrophobicity, high viscosity, ionic structure, ionic conductivity, very low volatility and biocompatibility are among the properties of ionic liquids making them attractive for electrode modification. From the point of view of their structure, ionic liquid-modified electrodes range from electrode substrates covered by ionic liquid film or droplet(s) to the more complex film consisting of few components including ionic liquid. Bulk-modified electrodes as carbon paste electrodes with ionic liquid as binder and carbon nanotubes - gel electrodes represent another two classes of reviewed electrodes. Electrodes modified with appended ionic liquid form the last group. Initially, research on ionic liquid-modified electrodes was oriented towards fundamental studies of ion transfer across ionic liquid/aqueous solution interface. Now, almost entire research effort in this area is oriented towards their application for electrochemical sensing with multicomponent films and carbon paste electrodes being most popular. © 2011 Elsevier B.V. All rights reserved.


Cieplak M.,Polish Academy of Sciences | Robbins M.O.,Johns Hopkins University
PLoS ONE | Year: 2013

A coarse-grained model is used to study the mechanical response of 35 virus capsids of symmetries T = 1, T = 2, T = 3, pseudo T = 3, T = 4, and T = 7. The model is based on the native structure of the proteins that constitute the capsids and is described in terms of the Cα atoms associated with each amino acid. The number of these atoms ranges between 8 460 (for SPMV - satellite panicum mosaic virus) and 135 780 (for NBV - nudaureli virus). Nanoindentation by a broad AFM tip is modeled as compression between two planes: either both flat or one flat and one curved. Plots of the compressive force versus plate separation show a variety of behaviors, but in each case there is an elastic region which extends to a characteristic force Fc. Crossing Fc results in a drop in the force and irreversible damage. Across the 35 capsids studied, both Fc and the elastic stiffness are observed to vary by a factor of 20. The changes in mechanical properties do not correlate simply with virus size or symmetry. There is a strong connection to the mean coordination number 〈z〉, defined as the mean number of interactions to neighboring amino acids. The Young's modulus for thin shell capsids rises roughly quadratically with 〈z〉-6, where 6 is the minimum coordination for elastic stability in three dimensions. © 2013 Cieplak, Robbins.


Janiuk A.,Polish Academy of Sciences | Mioduszewski P.,Polish Academy of Sciences | Moscibrodzka M.,University of Nevada, Las Vegas
Astrophysical Journal | Year: 2013

We calculate the structure and short-term evolution of a gamma-ray burst (GRB) central engine in the form of a turbulent torus accreting onto a stellar mass black hole. Our models apply to the short GRB events, in which a remnant torus forms after the neutron star-black hole or a double neutron star merger and is subsequently accreted. We study the two-dimensional, relativistic models and concentrate on the effects of the black hole and flow parameters as well as the neutrino cooling. We compare the resulting structure and neutrino emission to the results of our previous one-dimensional simulations. We find that the neutrino cooled torus launches a powerful mass outflow, which contributes to the total neutrino luminosity and mass loss from the system. The neutrino luminosity may exceed the Blandford-Znajek luminosity of the polar jets and the subsequent annihilation of neutrino-antineutrino pairs will provide an additional source of power to the GRB emission. © 2013. The American Astronomical Society. All rights reserved.


Rudnicki A.,Polish Academy of Sciences | Walborn S.P.,Federal University of Rio de Janeiro | Toscano F.,Federal University of Rio de Janeiro
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2012

We derive two quantum uncertainty relations for position and momentum coarse-grained measurements. Building on previous results, we first improve the lower bound for uncertainty relations using the Rényi entropy, particularly in the case of coarse-grained measurements. We then sharpen a Heisenberg-like uncertainty relation derived previously in that uses variances and reduces to the usual one in the case of infinite precision measurements. Our sharpened uncertainty relation is meaningful for any amount of coarse graining. That is, there is always a nontrivial uncertainty relation for coarse-grained measurement of the noncommuting observables, even in the limit of extremely large coarse graining. © 2012 American Physical Society.


Mai B.K.,Institute for Computational Science and Technology | Li M.S.,Polish Academy of Sciences
Biochemical and Biophysical Research Communications | Year: 2011

Two neuraminidase inhibitors, oseltamivir and zanamivir, are important drug treatments for influenza. Oseltamivir-resistant mutants of the influenza virus A/H1N1 and A/H5N1 have emerged, necessitating the development of new long-acting antiviral agents. One such agent is a new neuraminidase inhibitor R-125489 and its prodrug CS-8958. An atomic level understanding of the nature of this antiviral agents binding is still missing. We address this gap in our knowledge by applying steered molecular dynamics (SMD) simulations to different subtypes of seasonal and highly pathogenic influenza viruses. We show that, in agreement with experiments, R-125489 binds to neuraminidase more tightly than CS-8958. Based on results obtained by SMD and the molecular mechanics-Poisson-Boltzmann surface area method, we predict that R-125489 can be used to treat not only wild-type but also tamiflu-resistant N294S, H274Y variants of A/H5N1 virus as its binding affinity does not vary much across these systems. The high correlation level between theoretically determined rupture forces and experimental data on binding energies for the large number of systems studied here implies that SMD is a promising tool for drug design. © 2011 Elsevier Inc.


Han C.S.,Seoul National University | Jablonski P.G.,Seoul National University | Jablonski P.G.,Polish Academy of Sciences
Nature Communications | Year: 2010

Despite recent advances in our understanding of sexual conflict and antagonistic coevolution between sexes, the role of interspecific interactions, such as predation, in these evolutionary processes remains unclear. In this paper, we present a new male mating strategy whereby a male water strider Gerris gracilicornis intimidates a female by directly attracting predators as long as she does not accept the male's coercive copulation attempt. We argue that this male strategy is a counteradaptation to the evolution of the female morphological shield protecting her genitalia from coercive intromission by water strider males. The G. gracilicornis mating system clearly represents an effect expected from models of the coevolutionary arms race between sexes, whereby one sex causes a decrease in the fitness component of the other sex. Moreover, our study demonstrates a crucial role that interspecific interactions such as predation can have in the antagonistic coevolution between sexes. © 2010 Macmillan Publishers Limited. All rights reserved.


News Article | December 1, 2016
Site: phys.org

Nobody expected this. Computer simulations suggest that nitrogen, with its reluctance to react, could, at a high enough pressure, break the chemical rules and become extremely gregarious—a single atom would then be able to form even six chemical bonds. This surprising discovery has been made by researchers at the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw and the New Technology Centre at the University of Warsaw (CeNT UW). Chemists have long known that nitrogen may occasionally have a valency of five, which means that it is potentially able to form bonds with five other atoms. Another element with similar properties is phosphorus, which is adjacent to nitrogen in the periodic table. "Nitrogen, however, behaves differently to phosphorus," says Dr. Patryk Zaleski-Ejgierd (IPC PAS). "In practice, it forms five bonds with at most four other atoms, and more usually with three, as in the popular nitric acid HNO3. We decided to investigate in silico the possibility of obtaining a compound in which pentavalent nitrogen would combine with five neighbours by covalent interactions—chemical bonds. We analyzed thousands of crystal structures of nitrogen compounds with fluorine arising at high pressures. We were hoping to see some structures containing nitrogen pentafluoride NF5 particles. We were completely unprepared for the fact that in one of the crystals, we ran into ions with the formula NF6- in which the nitrogen atom bonds with as many as six fluorine atoms." Dr Dominik Kurzydlowski (CeNT UW), co-author of the publication in the journal Scientific Reports, explains the essence of the discovery: "Two electrons are typically required for the formation of a single covalent bond. The problem with nitrogen is that when creating various compounds, it 'trades' electrons so as to be constantly surrounded by eight of them. This constrains the total number of atoms bonded to nitrogen to no more than four. We were the first to find a stable crystal in which nitrogen breaks the octet rule, i.e. the requirement to possess exactly eight electrons. It then forms bonds involving a total of up to 12 electrons." Compounds in which an element breaks the octet rule are called hypervalent. Many elements can form hypervalent compounds, including phosphorus, sulphur and various metals. This phenomenon is advantageous because it significantly widens the number of possible compounds the element can form. For example, if it were not for hypervalency, sulphur would not form sulphuric acid and phosphorus could not be one of the building blocks of DNA. The calculations and simulations associated with the search for hypervalent nitrogen were carried out at the IPC PAS using density functional theory—that is, the method normally used in solid-state calculations. However, the discovery's authors used one of the more advanced embodiments of this theory, the hybrid functional. It enables highly accurate description of chemical bonds, but it takes much longer to perform the calculations. "The compounds we tested, as well as the conditions under which these compounds were formed, were very exotic. The accuracy of the calculations was therefore our absolute priority which is why we decided to use the hybrid functional for the calculations," says Dr. Kurzydlowski, and stresses that carrying out the simulation within a reasonable timeframe was possible thanks to cooperation with the Interdisciplinary Centre for Mathematical and Computational Modelling, University of Warsaw. A thorough analysis of the results of computer simulation allowed the researchers to identify the unique crystal structure that, with an increase in pressure, automatically ionizes in a very particular way. A reorganization takes place during which the molecular crystal, originally formed of a mixture of gases NF3 and F2, transforms into a complex ionic crystal constructed of NF4-, NF2+ and... NF6- ions. The pressure required for the synthesis of crystals containing NF6- amounts to 400 to 500 thousand atmospheres, which is within the reach of current experimental techniques. Simulations suggest that after formation, the crystals would remain metastable, even at much lower pressures. Does that also mean under normal atmospheric pressure? "I wouldn't bet too much money on that, but it cannot be completely ruled out that one day you will simply be able to pick up the crystals we predict with unique NF6- ions. If they do turn out to be so stable, who knows? Perhaps it will be possible to find some interesting applications for them," says Dr. Zaleski-Ejgierd. However, taking a crystal with NF6- ions into your hand would probably not be a very good idea. Nitrogen trifluoride is already a strong oxidizing agent that must be stored in steel cylinders. A crystal of nitrogen pentafluoride mixed with NF6- would be an even stronger oxidant, and we can assume that the construction of a container allowing for its safe storage could cause engineers considerable difficulties. Explore further: Superman can start worrying—we've almost got the formula for kryptonite More information: Dominik Kurzydłowski et al, Hexacoordinated nitrogen(V) stabilized by high pressure, Scientific Reports (2016). DOI: 10.1038/srep36049


Budd A.F.,University of Iowa | Stolarski J.,Polish Academy of Sciences
Journal of Morphology | Year: 2011

Recent molecular phylogenies conflict with traditional scleractinian classification at ranks ranging from suborder to genus, challenging morphologists to discover new characters that better agree with molecular data. Such characters are essential for including fossils in analyses and tracing evolutionary patterns through geologic time. We examine the skeletal morphology of 36 species belonging to the traditional families Faviidae, Merulinidae, Pectiniidae, and Trachyphylliidae (3 Atlantic, 14 Indo-Pacific, 2 cosmopolitan genera) at the macromorphological, micromorphological, and microstructural levels. Molecular analyses indicate that the families are not monophyletic groups, but consist of six family-level clades, four of which are examined [clade XV = Diploastrea heliopora; clade XVI = Montastraea cavernosa; clade XVII ("Pacific faviids") = Pacific faviids (part) + merulinids (part) + pectiniids (part) + M. annularis complex; clade XXI ("Atlantic faviids") = Atlantic faviids (part) + Atlantic mussids].Comparisons among molecular clades indicate that micromorphological and microstructural characters (singly and in combination) are clade diagnostic, but with two exceptions, macromorphologic characters are not. The septal teeth of "Atlantic faviids" are paddle-shaped (strong secondary calcification axes) or blocky, whereas the septal teeth of "Pacific faviids" are spine-shaped or multidirectional. Corallite walls in "Atlantic faviids" are usually septothecal, with occasional trabeculothecal elements; whereas corallite walls in "Pacific faviids" are usually trabeculothecal or parathecal or they contain abortive septa. Exceptions include subclades of "Pacific faviids" consisting of a) Caulastraea and Oulophyllia (strong secondary axes) and b) Cyphastrea (septothecal walls). Diploastrea has a diagnostic synapticulothecal wall and thick triangular teeth; Montastraea cavernosa is also distinct, possessing both "Pacific faviid" (abortive septa) and "Atlantic faviid" (paddle-shaped teeth) attributes. The development of secondary axes is similar in traditional Atlantic faviids and mussids, supporting molecular results placing them in the same clade. Subclades of "Pacific faviids" reveal differences in wall structure and the arrangement and distinctiveness of centers of rapid accretion. © 2010 Wiley-Liss, Inc.


Liu S.,Fuzhou University | Tang Z.-R.,Fuzhou University | Sun Y.,Argonne National Laboratory | Colmenares J.C.,Polish Academy of Sciences | Xu Y.-J.,Fuzhou University
Chemical Society Reviews | Year: 2015

The severe consequences of fossil fuel consumption have resulted in a need for alternative sustainable sources of energy. Conversion and storage of solar energy via a renewable method, such as photocatalysis, holds great promise as such an alternative. One-dimensional (1D) nanostructures have gained attention in solar energy conversion because they have a long axis to absorb incident sunlight yet a short radial distance for separation of photogenerated charge carriers. In particular, well-ordered spatially high dimensional architectures based on 1D nanostructures with well-defined facets or anisotropic shapes offer an exciting opportunity for bridging the gap between 1D nanostructures and the micro and macro world, providing a platform for integration of nanostructures on a larger and more manageable scale into high-performance solar energy conversion applications. In this review, we focus on the progress of photocatalytic solar energy conversion over controlled one-dimension-based spatially ordered architecture hybrids. Assembly and classification of these novel architectures are summarized, and we discuss the opportunity and future direction of integration of 1D materials into high-dimensional, spatially organized architectures, with a perspective toward improved collective performance in various artificial photoredox applications. This journal is © The Royal Society of Chemistry.


Fijalkowska I.J.,Polish Academy of Sciences | Schaaper R.M.,National Health Research Institute | Jonczyk P.,Polish Academy of Sciences
FEMS Microbiology Reviews | Year: 2012

High accuracy (fidelity) of DNA replication is important for cells to preserve the genetic identity and to prevent the accumulation of deleterious mutations. The error rate during DNA replication is as low as 10-9 to 10-11 errors per base pair. How this low level is achieved is an issue of major interest. This review is concerned with the mechanisms underlying the fidelity of the chromosomal replication in the model system Escherichia coli by DNA polymerase III holoenzyme, with further emphasis on participation of the other, accessory DNA polymerases, of which E. coli contains four (Pols I, II, IV, and V). Detailed genetic analysis of mutation rates revealed that (1) Pol II has an important role as a back-up proofreader for Pol III, (2) Pols IV and V do not normally contribute significantly to replication fidelity, but can readily do so under conditions of elevated expression, (3) participation of Pols IV and V, in contrast to that of Pol II, is specific to the lagging strand, and (4) Pol I also makes a lagging-strand-specific fidelity contribution, limited, however, to the faithful filling of the Okazaki fragment gaps. The fidelity role of the Pol III τ subunit is also reviewed. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.


Sato J.J.,Fukuyama University | Wolsan M.,Polish Academy of Sciences
Naturwissenschaften | Year: 2012

Umami is one of basic tastes that humans and other vertebrates can perceive. This taste is elicited by Lamino acids and thus has a special role of detecting nutritious, protein-rich food. The T1R1 + T1R3 heterodimer acts as the principal umami receptor. The T1R1 protein is encoded by the Tas1r1 gene. We report multiple inactivating (pseudogenizing) mutations in exon 3 of this gene from four phocid and two otariid species (Pinnipedia). Jiang et al. (Proc Natl Acad Sci U S A 109:4956-4961, 2012) reported two inactivating mutations in exons 2 and 6 of this gene from another otariid species. These findings suggest lost or greatly reduced umami sensory capabilities in these species. The widespread occurrence of a nonfunctional Tas1r1 pseudogene in this clade of strictly carnivorous mammals is surprising. We hypothesize that factors underlying the pseudogenization of Tas1r1 in pinnipeds may be driven by the marine environment to which these carnivorans (Carnivora) have adapted and may include: the evolutionary change in diet from tetrapod prey to fish and cephalopods (because cephalopods and living fish contain little or no synergistic inosine 5′-monophosphate that greatly enhances umami taste), the feeding behavior of swallowing food whole without mastication (because the T1R1 + T1R3 receptor is distributed on the tongue and palate), and the saltiness of sea water (because a high concentration of sodium chloride masks umami taste). © Springer-Verlag 2012.


Parlato R.,German Cancer Research Center | Kreiner G.,Polish Academy of Sciences
Journal of Molecular Medicine | Year: 2013

Nucleoli are the sites where synthesis of rRNA and ribosomal assembly take place. Along with these "traditional" roles, the nucleolus controls cellular physiology and homeostasis. The cellular and molecular alterations associated with impaired nucleolar activity ("nucleolar stress") have just started to be systematically explored in the nervous system taking advantage of newly available animal models lacking rRNA synthesis in specific neurons. These studies showed that nucleolar function is necessary for neuronal survival and that its modality of action differs between and within cell types. Nucleolar function is also crucial in pathology as it controls mitochondrial activity and critical stress signaling pathways mimicking hallmarks of human neurodegenerative diseases. This mini-review will focus on the modes of action of nucleolar stress and discuss how the manipulation of nucleolar activity might underscore novel strategies to extend neuronal function and survival. © 2012 The Author(s).


Gawronski B.,University of Western Ontario | Balas R.,Polish Academy of Sciences | Creighton L.A.,University of Western Ontario
Personality and Social Psychology Bulletin | Year: 2014

Evaluative conditioning (EC) is defined as the change in the evaluation of a conditioned stimulus (CS) due to its pairing with a valenced unconditioned stimulus (US). Counter to views that EC is the product of automatic learning processes, recent research has revealed various characteristics of nonautomatic processing in EC. The current research investigated whether the formation of conditioned attitudes can be intentionally controlled. Whereas EC effects on self-reported evaluations were reduced (enhanced) when participants were instructed to prevent (promote) the influence of CS-US pairings, EC effects on an evaluative priming measure remained unaffected by control instructions. Moreover, although EC effects on self-reported evaluations varied as a function of evaluative priming effects and recollective memory for CS-US pairings, motivation to control the influence of CS-US pairings qualified only the predictive relation of recollective memory. The results highlight functionally distinct contributions of uncontrollable encoding-related processes and controllable expression-related processes to EC effects. © 2013 by the Society for Personality and Social Psychology, Inc.


Missing data are commonly thought to impede a resolved or accurate reconstruction of phylogenetic relationships, and probabilistic analysis techniques are increasingly viewed as less vulnerable to the negative effects of data incompleteness than parsimony analyses. We test both assumptions empirically by conducting parsimony and Bayesian analyses on an approximately 1.5 × 106-cell (27 965 characters × 52 species) mustelid-procyonid molecular supermatrix with 62.7% missing entries. Contrary to the first assumption, phylogenetic relationships inferred from our analyses are fully (Bayesian) or almost fully (parsimony) resolved topologically with mostly strong support and also largely in accord with prior molecular estimations of mustelid and procyonid phylogeny derived with parsimony, Bayesian, and other probabilistic analysis techniques from smaller but complete or nearly complete data sets. Contrary to the second assumption, we found no compelling evidence in support of a relationship between the inferior performance of parsimony and taxon incompleteness (i.e. the proportion of missing character data for a taxon), although we found evidence for a connection between the inferior performance of parsimony and character incompleteness (i.e. no overlap in character data between some taxa). The relatively good performance of our analyses may be related to the large number of sampled characters, so that most taxa (even highly incomplete ones) are represented by a sufficient number of characters allowing both approaches to resolve their relationships.© The Willi Hennig Society 2009. © The Willi Hennig Society 2009.


News Article | December 10, 2015
Site: phys.org

Bacteriophage-based biosensors are a promising method for detecting particular species of bacteria. The sensitivity of current sensors coated with bacteriophages—that is, viruses that prey on bacteria—is far from ideal. In the journal Sensors and Actuators B: Chemical, researchers from the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw, Poland, have presented a method for creating layers of bacteriophages which significantly increases the efficiency of detection. This achievement paves the way for the production of low-cost biosensors capable of rapidly and reliably detecting specific species of bacteria. The late detection and identification of bacteria is the causes of many tragedies. The lack of reliable and rapid medical tests means that doctors only find out after several hours which bacterial species is wreaking havoc in the body of the patient. As a result, instead of administering the optimal antibiotic at an early stage of the disease, they have to guess—and they often get it wrong, with disastrous consequences for the patient. "Hospital-acquired infections, to which 100 thousand patients in the United States alone succumb each year, are just one of the problems arising from the lack of good methods for the detection of undesirable bacteria. Industrial contamination is no less important. For example, nobody wants to sell—much less buy—carrot juice with dangerous typhoid or sepsis bacteria. However, such cases continue to occur," says Dr. Jan Paczesny (IPC PAS). Attempts have been underway for some time to construct bacteria sensors that exploit bacteriophages. A single phage, with a length of about 200 nanometers, consists of a head (capsid) containing DNA or RNA and a tail through which genetic material is injected into the interior of the bacteria. The mouth of the tail is surrounded by fibrils. They perform a very important function as receptors detecting the presence of bacteria and recognizing their species. The bacteriophage cannot take any risks—its genetic material must reach the interior of only those bacteria that have suitably matching genetic machinery. If the phage were to inject its genetic code into the wrong bacteria, it would self-destruct rather than leveraging the bacteria for its reproduction. The specific structure of bacteriophages means that when they are deposited on the surface, they are arranged at random, and most of them cannot effectively penetrate the space around them with their receptors in search of bacteria. As a result, only a few bacteriophages in the detection layer of current biosensors can fulfill their role and the equipment's sensitivity is greatly reduced. "Phage heads are electrically negatively charged, whereas the filaments penetrating the surroundings are positive. The bacteriophage is therefore an electrically polarized entity. This gave us the idea of 'ordering' the bacteriophages using an electric field," says Ph.D. student Kinga Matułaa (IPC PAS). The idea was simple, but its implementation proved to be far from trivial. "There is a high pressure of up to 50 atm in the phage heads. This is what enables the bacteriophage to inject its genetic material. That's fine, but it means that bacteriophages like highly saline solutions, because the pressure difference between the head and the environment is reduced. Such solutions are highly conductive, and therefore the electric field inside them is present only in a thin layer at the surface—further on, it drops to zero," explains Ph.D. student Łukasz Richter. During their experiments, the Warsaw-based scientists, led by Prof. Robert Holyst, used an appropriately selected constant electric field. Bacteriophages were deposited on a carefully constructed glass substrate, coated first with titanium and then with gold. The titanium served as the glue binding the gold with the glass, while the gold was the main 'bait' to which the bacteriophages bound. Unfortunately, not only bacteriophages like gold—so do bacteria. To prevent the binding of random bacteria with the gold layer, the empty spaces between the deposited bacteriophages were covered with a neutral protein (casein). T4 bacteriophages that attack Escherichia coli bacteria were used to construct the new detection layer at the IPC PAS. The phages for the studies were prepared by the team of Prof. Marcin Łoś from the Department of Biology, University of Gdansk. "Virtually all of the bacteriophages in our detection layers stand on the substrate's surface, so they can easily spread out their receptors. The situation is somewhat similar to what is seen at a rock concert, where fans often raise their hands high above their heads in unison and wave them cheerfully in all directions. We have the impression that our phages are even happier, because we try not to place them too close to each other. After all, the neighbours' receptors should not interfere with each other," says Prof. Holyst with a smile. Meticulous laboratory tests have established that the bacteriophage layers produced using the method developed at the IPC PAS trap up to four times more bacteria than existing layers. As a result, their sensitivity is close to that of the best biosensors that use other, more time consuming and expensive, methods for the detection of bacteria. This method of preparing layers of ordered bacteriophages has numerous advantages. The creation of an external electric field, which is necessary to put the bacteriophages in order, is not very costly. The field acts through space and therefore direct contact of the electrodes with the solution is not required. The presence of an external electric field also means there is significantly less physico-chemical interference than when current is passed through the solution. At the same time, the method is fast and universal; it can be used not only for bacteriophages but also for other electrically polarized molecules. Explore further: Viruses help scientists battle pathogenic bacteria and improve water supply More information: Łukasz Richter et al. Ordering of bacteriophages in the electric field: Application for bacteria detection, Sensors and Actuators B: Chemical (2016). DOI: 10.1016/j.snb.2015.09.042


Zawadzki W.,Polish Academy of Sciences | Rusin T.M.,Orange Customer Service Sp. Z O. O.
Journal of Physics Condensed Matter | Year: 2011

We review recent research on Zitterbewegung (ZB, trembling motion) of electrons in semiconductors. A brief history of the subject is presented, the trembling motion in semi-relativistic and spin systems is considered and its main features are emphasized. ZB of charge carriers in monolayer and bilayer graphene as well as in carbon nanotubes is elaborated in some detail. We describe the effects of an external magnetic field on ZB using monolayer graphene as an example. The nature of electron ZB in crystalline solids is explained. We also review various simulations of the trembling motion in a vacuum and in semiconductors, and mention ZB-like wave phenomena in sonic and photonic periodic structures. An attempt is made to quote all the relevant literature on the subject. © 2011 IOP Publishing Ltd.


Bozek P.,AGH University of Science and Technology | Broniowski W.,Polish Academy of Sciences | Broniowski W.,Jan Kochanowski University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2015

Collective flow and femtoscopy in ultrarelativistic 3He-Au collisions are investigated within the 3+1-dimensional (3+1D) viscous event-by-event hydrodynamics. We evaluate elliptic and triangular flow coefficients as functions of the transverse momentum. We find the typical long-range ridge structures in the two-particle correlations in the relative azimuth and pseudorapidity, in the pseudorapidity directions of both Au and 3He. We also make predictions for the pionic interferometric radii, which decrease with the transverse momentum of the pion pair. All features found hint on collectivity of the dynamics of the system formed in 3He-Au collisions, with hydrodynamics leading to quantitative agreement with the up-to-now released data. © 2015 The Authors.


Rusin T.M.,Orange Customer Service Sp. Z O. O. | Zawadzki W.,Polish Academy of Sciences
Journal of Physics Condensed Matter | Year: 2014

We describe a possibility of creating non-stationary electron wave packets in zigzag carbon nanotubes (CNT) illuminated by short laser pulses. After the disappearance of the pulse the packet experiences a trembling motion (Zitterbewegung, ZB). The band structure of CNT is calculated using the tight-binding approximation generalized for the presence of radiation. By employing realistic pulse and CNT parameters we obtain the ZB oscillations with interband frequencies corresponding to specific pairs of energy bands. A choice of optimal parameters is presented in order to observe the phenomenon of ZB experimentally. The use of Gaussian wave packets to trigger the electron Zitterbewegung, as used in the literature, is critically reexamined. © 2014 IOP Publishing Ltd.


Wrobel D.,Poznan University of Technology | Graja A.,Polish Academy of Sciences
Coordination Chemistry Reviews | Year: 2011

The review concentrates on supermolecular electron-donor-acceptor systems composed of porphyrin dyes covalently linked to fullerene. These model systems are of a great importance not only in optoelectronic technologies but also in the life sciences in relation to respiration, photosynthesis and photomedicine. Results of studies of supermolecular systems composed of zinc porphyrin and its dyad covalently linked to one fullerene or two fullerene molecules (in chloroform solution and in the form of Langmuir-Blodgett layers on a gold substrate) are presented to illustrate the spectroscopic properties and electron transfer processes taking place in such systems. Some simpler models of donor-acceptor ensembles are also presented. Electronic absorption and fluorescence supported by reflectance-absorption in infrared and electron spin resonance spectroscopies as well examination of light-induced current generated in photoelectrochemical cells were used to follow the interactions, radiative and non-radiative processes accompanied with electron transfer from an electron donating species to an electron acceptor. The same methods could provide information on modification of the electronic structure of the systems. The observed changes in absorption and fluorescence quenching of porphyrins in the presence of fullerene have evidently shown charge redistribution both upon porphyrins linkage to fullerene and upon deposition of the systems on gold substrate resulting from the interaction between the organic layers and the solid. The results reported in this paper prove the donor-acceptor character of the zinc porphyrin-fullerene samples and influence of fullerene on dye photoactivity in the systems. © 2011 Elsevier B.V.


Kowiel M.,Poznan University of Medical Sciences | Jaskolski M.,Adam Mickiewicz University | Jaskolski M.,Polish Academy of Sciences | Dauter Z.,Argonne National Laboratory
Acta Crystallographica Section D: Biological Crystallography | Year: 2014

Despite the existence of numerous useful conventions in structural crystallography, for example for the choice of the asymmetric part of the unit cell or of reciprocal space, surprisingly no standards are in use for the placement of the molecular model in the unit cell, often leading to inconsistencies or confusion. A conceptual solution for this problem has been proposed for macromolecular crystal structures based on the idea of the anti-Cheshire unit cell. Here, a program and server (called ACHESYM; http://achesym.ibch.poznan.pl) are presented for the practical implementation of this concept. In addition, the first task of ACHESYM is to find an optimal (compact) macromolecular assembly if more than one polymer chain exists. ACHESYM processes PDB (atomic parameters and TLS matrices) and mmCIF (diffraction data) input files to produce a new coordinate set and to reindex the reflections and modify their phases, if necessary. © 2014 International Union of Crystallography.


Bozek P.,AGH University of Science and Technology | Bozek P.,Polish Academy of Sciences | Broniowski W.,Polish Academy of Sciences | Broniowski W.,Jan Kochanowski University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2013

Two-particle correlations in relative rapidity and azimuth are studied for the pPb collisions at the LHC energy of sNN=5.02 TeV in the framework of event-by-event (3. +. 1)-dimensional viscous hydrodynamics. It is found that for the highest-multiplicity events the observed ridge structures appear in a natural way, suggesting that collective flow may be an important element in the evolution of the system. We also discuss the role of the charge balancing and the transverse-momentum conservation. © 2012 Elsevier B.V.


Bozek P.,AGH University of Science and Technology | Bozek P.,Polish Academy of Sciences | Broniowski W.,Polish Academy of Sciences | Broniowski W.,Jan Kochanowski University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2013

The interferometric radii in the system formed in ultra-relativistic proton-lead collisions are investigated in a framework based on event-by-event (3. +. 1)-dimensional viscous hydrodynamics. We argue that the most central p-Pb collisions undergoing collective expansion behave similarly to the peripheral nucleus-nucleus collisions. The interferometric observables can serve as signatures of the formation of an extended fireball. © 2013 Elsevier B.V.


Bozek P.,AGH University of Science and Technology | Bozek P.,Polish Academy of Sciences
Physical Review C - Nuclear Physics | Year: 2014

I analyze the pion femtoscopy correlations in noncentral Au-Au and Pb-Pb collisions. The azimuthally sensitive Hanbury-Brown-Twiss (HBT) method is used to extract the interferometry radii depending on the azimuthal angle with respect to the second- and third-order event plane. The results are in semiquantitative agreement with the STAR collaboration data on the HBT radii with respect to the second-order reaction plane, with the preliminary PHENIX collaboration data on the HBT radii with respect to the third-order reaction plane in Au-Au collisions at 200 GeV, and with the preliminary ALICE collaboration data for the HBT radii with respect to the second-order event plane for Pb-Pb collisions at 2.76 TeV. © 2014 American Physical Society.


Bozek P.,AGH University of Science and Technology | Bozek P.,Polish Academy of Sciences | Broniowski W.,Polish Academy of Sciences | Broniowski W.,Jan Kochanowski University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2014

The triangular flow in ultrarelativistic 3He-Au collisions at RHIC energies is enhanced due to the triangular arrangement of the nucleon configurations in 3He. We study the fireball eccentricities in the Glauber Monte Carlo model and find that since the configurations of the projectile 3He are elongated triangles, the created fireball has not only a significant triangularity but also a large ellipticity. The dependence of the triangularity on centrality is weak, so it cannot be extracted from the centrality dependence of the triangular flow v3, as it is dominated by the centrality dependence of the hydrodynamic response. We propose to look at the centrality dependence of the ratio vn{4}/vn{2}, where the uncertainties from the hydrodynamic response cancel, and show that the basic signature of the geometry-driven collective flow is the rise of the ratio v3{4}/v3{2} with the number of participant nucleons for centralities less than 10%. © 2014 The Authors.


Wilbik A.,Polish Academy of Sciences | Wilbik A.,University of Missouri | Keller J.M.,University of Missouri
IEEE Transactions on Fuzzy Systems | Year: 2013

In this paper, we consider the problem of evaluating the similarity of two sets of linguistic summaries of sensor data. Huge amounts of available data cause a dramatic need for summarization. In continuous monitoring, it is useful to compare one time interval of data with another, for example, to detect anomalies or to predict the onset of a change from a normal state. Assuming that summaries capture the essence of the data, it is sufficient to compare only those summaries, i.e., they are descriptive features for recognition. In previous work, we developed a similarity measure between two individual summaries and proved that the associated dissimilarity is a metric. Additionally, we proposed some basic methods to combine these similarities into an aggregate value. Here, we develop a novel parameter free method, which is based on fuzzy measures and integrals, to fuse individual similarities that will produce a closeness measurement between sets of summaries. We provide a case study from the eldercare domain where the goal is to compare different nighttime patterns for change detection. The reasons for studying linguistic summaries for eldercare are twofold: First, linguistic summaries are the natural communication tool for health care providers in a decision support system, and second, due to the extremely large volume of raw data, these summaries create compact features for an automated reasoning for detection and prediction of health changes as part of the decision support system. © 2012 IEEE.


Walanus A.,AGH University of Science and Technology | Nalepka D.,Polish Academy of Sciences
Radiocarbon | Year: 2010

The "calibration" of arbitrarily defined (in some sense, "conventional") ages, given in conventional radiocarbon years BP, is now becoming necessary because the term "radiocarbon age" is used less often in archaeological and Quaternary practice. The standard calibration procedure is inappropriate here because Mangerud's boundaries are not measurement results. Thus, another approach to the problem is proposed in order to model the natural situation of many, uniformly distributed, dated samples, which should be similarly divided by the original and "calibrated" boundary. However, the result depends on the value of the typical measurement error and is not unequivocal. © 2010 by the Arizona Board of Regents on behalf of the University of Arizona.


Derewiaka D.,Warsaw University of Life Sciences | Molinska E.,Polish Academy of Sciences
Food Chemistry | Year: 2015

The aim of the study was to characterise products of cholesterol standard changes during thermal processing. Cholesterol was heated at 120 °C, 150 °C, 180 °C and 220 °C from 30 to 180 min. The highest losses of cholesterol content were found during thermal processing at 220 °C, whereas the highest content of cholesterol oxidation products was observed at temperature of 150 °C. The production of volatile compounds was stimulated by the increase of temperature. Treatment of cholesterol at higher temperatures i.e. 180 °C and 220 °C led to the formation of polymers and other products e.g. cholestadienes and fragmented cholesterol molecules. Further studies are required to identify the structure of cholesterol oligomers and to establish volatile compounds, which are markers of cholesterol transformations, mainly oxidation. © 2014 Elsevier Ltd. All rights reserved.


Gnach A.,Wroclaw Research Center | Gnach A.,Polish Academy of Sciences | Gnach A.,Institute of Low Temperature And Structure Research | Bednarkiewicz A.,Wroclaw Research Center | Bednarkiewicz A.,Institute of Low Temperature And Structure Research
Nano Today | Year: 2012

Due to exceptional photo-physical properties, up-converting nanoparticles (UCNPs) are promising and advantageous alternative to conventional fluorescent labels used in many bio-medical applications. The first part of this review aims at presenting these properties as well as the current state-of-the-art in the up-conversion enhancement, NPs surface functionalization and bioconjugation. In the second part of the paper, the applications of UCNPs and currently available detection instrumentation are discussed in the view of the distinctive properties of these markers. Because the growing widespread use of the biofunctionalized NPs, scarce instrumentation for up-conversion detection is reviewed. Finally, the challenges and future perspectives of the UCNPs are discussed. © 2012 Elsevier Ltd.


Bozek P.,AGH University of Science and Technology | Broniowski W.,Polish Academy of Sciences | Broniowski W.,Jan Kochanowski University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2016

The decorrelation of the orientation of the event-plane angles in the initial state of relativistic Pb-Pb and p-Pb collisions, the "torque effect", is studied in a model of entropy deposition in the longitudinal direction involving fluctuations of the longitudinal source profile on large scales. The radiation from a single wounded nucleon is asymmetric in space-time rapidity. It is assumed that the extent in rapidity of the region of deposited entropy is random. Fluctuations in the deposition of entropy from each source increase the event-plane decorrelation: for Pb-Pb collisions the change is moderate, while for p-Pb collisions the mechanism is absolutely essential to generate any sizable decorrelation. We also show that the experimental data for rank-four flow may be explained via folding of the elliptic flow. The results suggest the existence of long range fluctuations in the space-time distribution of entropy in the initial stages of relativistic nuclear collisions. © 2015 The Authors.


Bentivegna E.,Max Planck Institute For Gravitationsphysik | Korzynski M.,Polish Academy of Sciences
Classical and Quantum Gravity | Year: 2013

We present the numerical evolution of a family of conformally-flat, infinite, expanding cubic black-hole lattices. We solve for the initial data using an initial-data prescription presented recently, along with a new multigrid solver developed for this purpose. We then apply the standard tools of numerical relativity to calculate the time development of this initial dataset and derive quantities of cosmological relevance, such as the scaling of proper lengths. Similarly to the case of S3 lattices, we find that the length scaling remains close to the analytical solution for Friedmann- Lemaître-Robertson-Walker cosmologies throughout our simulations, which span a window of about one order of magnitude in the growth of the scale factor. We highlight, however, a number of important departures from the Friedmann-Lemaître-Robertson-Walker class. © 2013 IOP Publishing Ltd.


Alaoui A.,University of Bern | Lipiec J.,Polish Academy of Sciences | Gerke H.H.,Leibniz Center for Agricultural Landscape Research
Soil and Tillage Research | Year: 2011

Compaction and shearing, as well as the rearrangement of soil aggregates and clods due to shrinkage, among other processes, can strongly affect the pore geometry of agricultural soils. These soil structural changes directly affect soil water movement by altering the hydraulic properties that are commonly described by the soil water retention curve (WRC) and the unsaturated hydraulic conductivity function (HCF). This review focuses on recent advances in the understanding and evaluation of changes in hydraulic functions in relation to compacted soil. The development of hydromechanical models due to recent advances with more sophisticated methods enables quantification of the effects of compaction on the hydraulic conductivity functions at the pore scale of aggregated soil. However, it remains unclear how to up-scale the dynamic, in terms of inter-aggregate pore models, into the continuum-scale dual-porosity models in the form of effective parameters, particularly regarding effective hydraulic properties for the preferential flow domain. While hydromechanical models fail to describe water flow and hydraulic conductivity at the relevant scales and water saturation ranges, the continuum-based flow models rely on effective parameters that are mainly empirical or are based on fitting model results to data. Input data usually do not address temporal changes in the arrangement of aggregates induced by soil compaction and shrinkage. This review presents a concept that summarizes the changes in structural and textural porosity upon compaction. It suggests focusing on the extension of existing hydraulic and hydromechanical models to include the pore structural changes that account for the movement and rearrangement of soil aggregates and the resulting changes in the soil hydraulic properties which basically manifest the effects of shearing and compaction on water flow. © 2011 Elsevier B.V.


Sorbjan Z.,Marquette University | Sorbjan Z.,Polish Academy of Sciences
Quarterly Journal of the Royal Meteorological Society | Year: 2010

Three gradient-based scaling systems for the stably stratified boundary layer are introduced and examinedbyusing data collected during the SHEBAfieldprogramme in theArctic. The resulting similarity functions forfluxes andvariances are expressed in an analytical form, which is expected to be essentially unaffected by self-correlation in a very stable regime. The flux Richardson number Rf is found to be proportional to the Richardson number Ri, with the proportionality coefficient varying slightly with stability, from 1.11 to 1.47. The Prandtl number decreases from 0.9 in nearly neutral conditions to 0.7 for larger values of Ri. The negative correlation coefficient between the vertical velocity and temperature, -rwθ, has a local maximum at Ri of about 0.08, and monotonically decreases with larger values of the Richardson number. The turbulent kinetic energy budget indicates that for Ri > 0.7, turbulence must be non-stationary, i.e. decaying or sporadic. Turbulence within the stably stratified boundary layer can be classified by four regimes: 'nearly neutral' (0 < Ri < 0.02), 'weakly stable' (0.02 < Ri < 0.12), 'very stable' (0.12 < Ri < 0.7), and 'extremely stable' (Ri > 0.7). © 2010 Royal Meteorological Society.


Banski J.,Polish Academy of Sciences | Wesolowska M.,Maria Curie Sklodowska University
Landscape and Urban Planning | Year: 2010

The analysis presented here concerns the influence of housing construction on spatial systems and the physiognomy of rural settlements serving various economic functions. In addition, the study offers an assessment of the influence new construction is having on the living conditions experienced by country-dwellers and the appearance and aesthetics characterising rural settlements. Particular attention is paid to modern housing construction, which only began to flourish in Poland in the period of economic transformation. A basis for the work has been provided by detailed research (field surveys, questionnaires and interviews) carried out in 15 villages located in Lublin voivodeship, eastern Poland. Changes in the spatial structure of villages under the influence of the new building are presented by reference to three villages representative of the residential, tourist-recreational and agricultural functional types. The post-1989 process of economic transformation has magnified spatial differences as regards the kind of new housing construction taking place in rural areas. The intensity at which new building is taking place is very much a function of the size of the adjacent urban centre and the area's distance from it. Housing construction concentrates close to the main transport arteries, along which a belt of enhanced economic activity is to be found. Pressure from new investors is giving rise to a transformation of the natural environment, as well to the appearance of new conflicts between agriculture and housing. The development of new styles of building has led to changes in traditional configuration of villages. © 2009 Elsevier B.V. All rights reserved.


Huy Phan A.,RIKEN | Cichocki A.,Polish Academy of Sciences
Neurocomputing | Year: 2011

Parallel factor analysis (PARAFAC) is a tensor (multiway array) factorization method which allows to find hidden factors (component matrices) from a multidimensional data. Most of the existing algorithms for the PARAFAC, especially the alternating least squares (ALS) algorithm need to compute Khatri-Rao products of tall factors and multiplication of large matrices, and due to this require high computational cost and large memory and are not suitable for very large-scale-problems. Hence, PARAFAC for large-scale data tensors is still a challenging problem. In this paper, we propose a new approach based on a modified ALS algorithm which computes Hadamard products, instead Khatri-Rao products, and employs relatively small matrices. The new algorithms are able to process extremely large-scale tensors with billions of entries. Extensive experiments confirm the validity and high performance of the developed algorithm in comparison with other well-known algorithms. © 2011 Elsevier B.V.


Krzywda S.,Adam Mickiewicz University | Jaskolski M.,Adam Mickiewicz University | Jaskolski M.,Polish Academy of Sciences | Rolka K.,University of Gdansk | Stawikowski M.J.,Torrey Pines Institute for Molecular Studies
Acta Crystallographica Section D: Biological Crystallography | Year: 2014

Peptide-peptoid hybrids are found to be potent inhibitors of serine proteases. These engineered peptidomimetics benefit from both types of units of the biopolymeric structure: the natural inhibitor part serves as a good binding template, while the P1-positioned peptoid component provides complete resistance towards proteolysis. In this report, the mechanism of proteolytic resistance of a P1 peptoid-containing analogue is postulated based on the crystal structure of the (NLys)5-modified sunflower trypsin inhibitor SFTI-1 in complex with bovine trypsin solved at 1.29 Å resolution. The structural differences between the (NLys)5SFTI-1-trypsin complex and the native SFTI-1-trypsin complex are surprisingly small and reveal the key role of the carbonyl group of the Ser214 residue of the enzyme, which is crucial for binding of the inhibitor and plays a crucial role in proteolysis mediated by serine proteases. The incorporated NLys5 peptoid residue prevents Ser214 from forming a hydrogen bond to the P1 residue, and in turn Gln192 does not form a hydrogen bond to the carbonyl group of the P2 residue. It also increases the distance between the Ser214 carbonyl group and the Ser195 residue, thus preventing proteolysis. The hybrid inhibitor structure reported here provides insight into protein-protein interaction, which can be efficiently and selectively probed with the use of peptoids incorporated within endogenous peptide ligands. © 2014 International Union of Crystallography.


Nagy Z.L.,Foundation for School | Postawa T.,Polish Academy of Sciences
Animal Conservation | Year: 2011

Caves offer bats refuges for hibernation, breeding and other social events. Their quality is important for species distribution. The role of cave microclimate as well as other environmental factors influencing the distribution of cave-dwelling species, is poorly known. We tested the significance of cave variables (length, temperature, elevation, occurrence of water) and geographical location for the presence of bats during hibernation and the breeding season in five regions in Romania. To detect species' environmental relationships, we used canonical correspondence analyses for winter bat aggregations and principal components analysis for maternity colonies. We analysed the factors influencing the distribution of bats by using two sets of explanatory variables reflecting cave characteristics and geographical locations. Winter aggregation was divided into three groups: (1) bat species that prefer high temperatures (Rhinolophus euryale, Myotis cappacinii) and hibernate at a low altitude; (2) species ranging from mid- to high elevation and low temperature (Myotis myotis/oxygnathus group); (3) species that hibernate in large, cold cave systems with a constant flow of the water (Pipistrellus pipistrellus, Nyctalus noctula, Barbastella barbastellus). Maternity colonies were divided into those that select either high (rhinolophids) or low temperatures (My. myotis/oxygnathus and Miniopterus schreibersii). The most important factors influencing the distribution of bats are the temperature in caves and their geographical location. This information was combined with IUCN's Red List data as well as with the number of individuals occurring in caves with the aim of identifying the key sites for conservation. The majority of these sites, which also constitute the refuges for vulnerable species, are located in west and south-western Romania. Seven caves provide shelter throughout the year for 122000 individuals of 14 species. © 2010 The Authors. Animal Conservation © 2010 The Zoological Society of London.


Sorbjan Z.,Marquette University | Sorbjan Z.,Polish Academy of Sciences
Boundary-Layer Meteorology | Year: 2012

Empirical similarity functions of the Richardson number, obtained from bin-averaged data in the lower part of the stable boundary layer, show an undesired dependence on height at which the observations are collected. A correction of this flaw is proposed and tested by employing the neutral mixing length lo as a similarity scale for height. The function of height describing lo is assumed to be linear in the surface layer, and approaching a specified value with increasing height. The modification does not alter the dependence of similarity functions on the Richardson number, and is shown to be supported by the Cooperative Atmospheric-Surface Exchange Study-1999 (CASES-99) data. © 2011 The Author(s).


Sorbjan Z.,Marquette University | Sorbjan Z.,Polish Academy of Sciences
Boundary-Layer Meteorology | Year: 2012

We document numerical experiments with a single-column, high-resolution model of the stable boundary layer. The model resolves the logarithmic layer, and does not require inverting the Monin-Obukhov similarity functions in order to calculate the surface fluxes. The turbulence closure is based on the K-theory approach, with a new form of stability functions of the Richardson number, evaluated by using the Surface Heat Budget of the Arctic Ocean (SHEBA) and the Cooperative Atmosphere-Surface Exchange Study (CASES-99) data. A comparison with two, high-resolution large-eddy simulation models shows very good agreement. The reported numerical experiments test the effects of shear, surface cooling, the Coriolis parameter, subsidence, and baroclinicity. The time evolution of the drag coefficient, the heat-transfer coefficient, and the cross-isobar angle is also evaluated. © 2011 The Author(s).


News Article | November 22, 2016
Site: www.prnewswire.com

FREDERICKSBURG, Va., Nov. 22, 2016 /PRNewswire/ -- PAS Systems International Inc., announces the market release of the AquilaScan Oral Fluid Drug Screener designed for law enforcement. AquilaScan is an affordable, handheld, qualitative screening instrument with a simple to use field data...


Chmura J.,University School of Physical Education in Wroclaw | Nazar K.,Polish Academy of Sciences
International Journal of Psychophysiology | Year: 2010

During aerobic exercise with increasing intensities choice reaction time (CRT) progressively shortens up to 60-80% of maximal workload, and then it rapidly increases. The aim of this study was to determine whether workload associated with the shortest CRT operationally called "the psychomotor fatigue threshold" is related to the metabolic response to exercise. Thirteen male soccer players (aged 23.3 ± 1.0 yrs) participated in this study. Before and after 6 weeks of training in the pre-competition period they underwent treadmill test at 0 grade with running speed increasing every 3 min by 2 km/h starting from 6 km/h until exhaustion. At each stage of exercise CRT, heart rate, respiratory gas exchange and blood lactate [LA] were measured and the workload corresponding to [LA] of 4 mmol/l (OBLA) was recorded. After training, CRT was significantly shortened at rest (from m ± SEM = 345 ± 12 to 317 ± 12 ms) and during exercise (from 304 ± 10 to 285 ± 11 ms at the psychomotor fatigue threshold and from 359 ± 13 to 331 ± 13 ms, p < 0.001at the last stage). Both OBLA and the psychomotor fatigue threshold were shifted towards greater running velocities (by 0.92 ± 0.26 and 0.85 ± 0.22 km/h, respectively). The psychomotor fatigue threshold exceeded OBLA both before and after training. Significant correlations were ascertained between OBLA and psychomotor fatigue threshold (r = 0.97) and between the changes in OBLA occurring during training and those in psychomotor fatigue threshold (r = 0.88). It is concluded that endurance training not only increases exercise tolerance due to its influence on metabolism but also facilitates psychomotor performance during heavy exercise. © 2010 Elsevier B.V. All rights reserved.


Broniowski W.,Polish Academy of Sciences | Rybczynski M.,Jan Kochanowski University
Physical Review C - Nuclear Physics | Year: 2010

We investigate the influence of the central two-body nucleon-nucleon correlations on several quantities observed in relativistic heavy-ion collisions. It is demonstrated with explicit Monte Carlo simulations that the basic correlation measures observed in relativistic heavy-ion collisions, such as the fluctuations of participant eccentricity, initial size fluctuations, or the fluctuations of the number of sources producing particles, are all sensitive to the inclusion of the two-body correlations. The effect is at the level of about 10-20%. Moreover, the realistic (Gaussian) correlation function gives indistinguishable results from the hard-core repulsion, with the expulsion distance set to 0.9fm. Thus, we verify that for investigations of the considered correlation measures, it is sufficient to use the Monte Carlo generators accounting for the hard-core repulsion. © 2010 The American Physical Society.


Rozanski A.,Polish Academy of Sciences | Galeski A.,Polish Academy of Sciences | Debowska M.,Wrocław University
Macromolecules | Year: 2011

The effect of stabilizers, additives, and low molecular weight fractions on cavitation during tensile drawing was studied in polypropylene. The additives were extracted from compression molded samples by critical CO2 and also by a mixture of nonsolvents. The extract was an oily liquid composed of antioxidant, processing stabilizer, and a spectrum of low molecular weight fractions of polypropylene. Purified polypropylene exhibited surprisingly more intense cavitation than pristine polypropylene as it was determined by small-angle X-ray scattering and volume strain measurements. Intensification of the cavitation process in the purified samples was explained by the changes in the amorphous phase, namely, the changes in free volume by eliminating low fractions and soluble additives. An increase in free volume was probed with positron annihilation lifetime spectroscopy. Intense formation of cavitation pores in purified polypropylene proves that initiation of cavitation in polypropylene has a homogeneous nature. © 2010 American Chemical Society.


Ryblewski R.,Polish Academy of Sciences | Florkowski W.,Polish Academy of Sciences | Florkowski W.,Jan Kochanowski University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

A set of kinetic equations is used to study equilibration of the anisotropic quark-gluon plasma produced by decays of color flux tubes possibly created at the very early stages of ultrarelativistic heavy-ion collisions. The decay rates of the initial color fields are given by the Schwinger formula, and the collision terms are treated in the relaxation-time approximation. By connecting the relaxation time with viscosity we are able to study production and thermalization processes in the plasma characterized by different values of the ratio of the shear viscosity to entropy density, η̄. For the lowest (Kovtun-Son-Starinets) value of this ratio, 4πη̄=1, and realistic initial conditions for the fields, the system approaches the viscous-hydrodynamics regime within 1-2 fm/c. On the other hand, for larger values of the viscosity, 4πη̄≥3, the collisions in the plasma become inefficient to destroy collective phenomena which manifest themselves as oscillations of different plasma parameters. The presence of such oscillations brings in differences between the kinetic and hydrodynamic descriptions, which suggest that the viscous-hydrodynamics approach after 1-2 fm/c is not complete if 4πη̄≥3 and should be extended to include dissipative phenomena connected with color conductivity. © 2013 American Physical Society.


Gusakov M.E.,Saint Petersburg State Polytechnic University | Haensel P.,Polish Academy of Sciences | Kantor E.M.,RAS Ioffe Physical - Technical Institute
Monthly Notices of the Royal Astronomical Society | Year: 2014

Observations of massive (M ≈2.0 M⊙) neutron stars (NSs), PSRs J1614-2230 and J0348+0432, rule out most of the models of nucleon-hyperon matter employed in NS simulations. Here, we construct three possible models of nucleon-hyperon matter consistent with the existence of 2 M⊙ pulsars as well as with semi-empirical nuclear matter parameters at saturation, and semi-empirical hypernuclear data. Our aim is to calculate for these models all the parameters necessary for modelling dynamics of hyperon stars (such as equation of state, adiabatic indices, thermodynamic derivatives, relativistic entrainment matrix, etc.), making them available for a potential user. To this aim a general non-linear hadronic Lagrangian involving σωρφσ* meson fields, as well as quartic terms in vector-meson fields, is considered. A universal scheme for calculation of thel = 0, 1 Landau Fermi-liquid parameters and relativistic entrainment matrix is formulated in the mean-field approximation. Use of this scheme allow us to obtain numerical tables with the equation of state, Landau quasi-particle effective masses, adiabatic indices, the l = 0, 1 Landau Fermi-liquid parameters, and the relativistic entrainment matrix for the selected models of nucleon-hyperon matter. These data are available online and suitable for numerical implementation in computer codes modelling various dynamical processes in NSs, in particular, oscillations of superfluid NSs and their cooling. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.


Bozek P.,Polish Academy of Sciences | Bozek P.,University of Rzeszow | Broniowski W.,Polish Academy of Sciences | Broniowski W.,Jan Kochanowski University
Physical Review Letters | Year: 2012

We demonstrate that, in the framework of the event-by-event hydrodynamics followed by statistical hadronization, the proper charge conservation in the mechanism of hadron production provides the crucial nonflow component and leads to agreement with the two-dimensional two-particle correlation data in relative azimuthal angle and pseudorapidity at soft transverse momenta (p T<2GeV). The falloff of the same-side ridge in relative pseudorapidity follows from the fact that a pair of particles with balanced charges is emitted from the same fluid element, whose collective velocity collimates the momenta of the pair. We reproduce basic experimental features of the two-dimensional correlation function, such as the dependence on the relative charge and centrality, as well as the related charge balance functions and the harmonic flow coefficients as functions of the relative pseudorapidity. © 2012 American Physical Society.


Ryblewski R.,Polish Academy of Sciences | Florkowski W.,Polish Academy of Sciences | Florkowski W.,Jan Kochanowski University
European Physical Journal C | Year: 2011

A recently formulated framework of highly anisotropic and strongly dissipative hydrodynamics (ADHYDRO) is used to describe the evolution of matter created in ultra-relativistic heavy-ion collisions. New developments of the model contain: the inclusion of asymmetric transverse expansion (combined with the longitudinal boost-invariant flow) and comparisons of the model results with the RHIC data, which have become possible after coupling of ADHYDRO with THERMINATOR. Various soft-hadronic observables (the transverse-momentum spectra, the elliptic flow coefficient v2, and the HBT radii) are calculated for different initial conditions characterized by the value of the initial pressure asymmetry. We find that as long as the initial energy density profile is unchanged the calculated observables remain practically the same. This result indicates the insensitivity of the analyzed observables to the initial anisotropy of pressure (provided the initial entropy density is changed to keep the initial energy density fixed) and suggests that the complete thermalization of the system may be delayed to easily acceptable times of about 1 fm/c. © Springer-Verlag / Società Italiana di Fisica 2011.


Tinti L.,Jan Kochanowski University | Florkowski W.,Jan Kochanowski University | Florkowski W.,Polish Academy of Sciences
Physical Review C - Nuclear Physics | Year: 2014

The earlier projection method introduced for boost-invariant and cylindrically symmetric systems is used to introduce a new formulation of anisotropic hydrodynamics that allows for three substantially different values of pressure acting locally in three different directions. Our considerations are based on the Boltzmann kinetic equation with the collision term treated in the relaxation-time approximation and the momentum anisotropy is included explicitly in the leading term of the distribution function. A novel feature of our work is the complete analysis of the second moment of the Boltzmann equation, in addition to the zeroth and first moments that have been analyzed in earlier studies. We define the final equations of anisotropic hydrodynamics in the leading order as a subset of the analyzed moment equations (and their linear combinations) which agree with the Israel-Stewart theory in the case of small pressure anisotropies. © 2014 American Physical Society.


Ryblewski R.,Polish Academy of Sciences | Florkowski W.,Polish Academy of Sciences | Florkowski W.,Jan Kochanowski University
Physical Review C - Nuclear Physics | Year: 2012

A recently formulated model of highly-anisotropic and strongly dissipative hydrodynamics is used in 3+1 dimensions to study behavior of matter produced in ultrarelativistic heavy-ion collisions. We search for possible effects of the initial high anisotropy of pressure on the final soft-hadronic observables. We find that, by appropriate adjustment of the initial energy density and/or the initial pseudorapidity distributions, the effects of the initial anisotropy of pressure may be easily compensated, and the final hadronic observables become insensitive to early dynamics. Our results indicate that the early thermalization assumption is not necessary to describe hadronic data, in particular, to reproduce the measured elliptic flow v 2. The complete thermalization of matter (local equilibration) may take place only at times of about 1-2 fm/c, in agreement with the results of microscopic models. © 2012 American Physical Society.


Florkowski W.,Jan Kochanowski University | Florkowski W.,Polish Academy of Sciences | Ryblewski R.,Polish Academy of Sciences
Physical Review C - Nuclear Physics | Year: 2012

Tensors describing boost-invariant and cylindrically symmetric expansion of a relativistic dissipative fluid are decomposed in a suitable chosen basis of projection operators. This leads to a simple set of scalar equations which determine the fluid behavior. As special examples, we discuss the case of the Israel-Stewart theory and the model of highly anisotropic and strongly dissipative hydrodynamics (ADHYDRO). We also introduce the matching conditions between the ADHYDRO description suitable for the very early stages of heavy-ion collisions and the Israel-Stewart theory applicable to later stages when the system is close to equilibrium. © 2012 American Physical Society.


McIntyre J.,Polish Academy of Sciences | Woodgate R.,U.S. National Institutes of Health
DNA Repair | Year: 2015

Posttranslational modification of proteins often controls various aspects of their cellular function. Indeed, over the past decade or so, it has been discovered that posttranslational modification of lysine residues plays a major role in regulating translesion DNA synthesis (TLS) and perhaps the most appreciated lysine modification is that of ubiquitination. Much of the recent interest in ubiquitination stems from the fact that proliferating cell nuclear antigen (PCNA) was previously shown to be specifically ubiquitinated at K164 and that such ubiquitination plays a key role in regulating TLS. In addition, TLS polymerases themselves are now known to be ubiquitinated. In the case of human polymerase η, ubiquitination at four lysine residues in its C-terminus appears to regulate its ability to interact with PCNA and modulate TLS. Within the past few years, advances in global proteomic research have revealed that many proteins involved in TLS are, in fact, subject to a previously underappreciated number of lysine modifications. In this review, we will summarize the known lysine modifications of several key proteins involved in TLS; PCNA and Y-family polymerases η, ι, κ and Rev1 and we will discuss the potential regulatory effects of such modification in controlling TLS in vivo. © 2015.


Piwosz K.,Polish Academy of Sciences | Pernthaler J.,University of Zürich
Environmental Microbiology | Year: 2010

We investigated the temporal dynamics and trophic role of different nanoflagellates in surface waters of the Gulf of Gdańsk (Baltic Sea) between April and October 2007. Two 18S rRNA gene clone libraries were constructed from samples collected in spring and summer, and weekly changes in the abundances of five phylogenetic groups were studied by fluorescence in situ hybridization with newly designed probes. Stramenopiles affiliated with MAST-6 and Pedinellales were most numerous in spring but rare in summer. Both groups formed short-lived blooms during a sudden drop of salinity due to riverine influx (from 7.1 to 6.2 practical salinity units). The analysis of food vacuole content suggested that MAST-6 nanoflagellates were herbivorous, whereas bacterivory was found both in plastidic and aplastidic pedinellid populations. Members of an uncultured lineage of aplastidic, bacterivorous cercozoans distantly related to Ebria tripartita were more abundant in summer when water temperatures exceeded 17°C. Multicellular trophonts and/or free-living single cell stages of two lineages of Group 1 parasitic Syndiniales (alveolates) were present in spring and early summer. One of these alveolate populations repeatedly peaked before and after the freshwater influx, but was conspicuously absent throughout the period of decreased salinity. Our results indicate that nanoflagellate populations in coastal surface waters may form short-lived blooms that can only be detected by high-frequency sampling, and that may be related both to seasonal development and to sporadic (e.g. mixing) events. In view of their trophic diversity we moreover suggest that nanoflagellates in eutrophic coastal waters should not be regarded as a single functional unit. © 2009 Society for Applied Microbiology and Blackwell Publishing Ltd.


Jaskolski M.,Polish Academy of Sciences | Dauter Z.,Argonne National Laboratory | Wlodawer A.,NCI Inc
FEBS Journal | Year: 2014

As a contribution to the celebration of the year 2014, declared by the United Nations to be 'The International Year of Crystallography', the FEBS Journal is dedicating this issue to papers showcasing the intimate union between macromolecular crystallography and structural biology, both in historical perspective and in current research. Instead of a formal editorial piece, by way of introduction, this review discusses the most important, often iconic, achievements of crystallographers that led to major advances in our understanding of the structure and function of biological macromolecules. We identified at least 42 scientists who received Nobel Prizes in Physics, Chemistry or Medicine for their contributions that included the use of X-rays or neutrons and crystallography, including 24 who made seminal discoveries in macromolecular sciences. Our spotlight is mostly, but not only, on the recipients of this most prestigious scientific honor, presented in approximately chronological order. As a summary of the review, we attempt to construct a genealogy tree of the principal lineages of protein crystallography, leading from the founding members to the present generation. © Published 2014.


Rybczynski M.,Jan Kochanowski University | Broniowski W.,Jan Kochanowski University | Broniowski W.,Polish Academy of Sciences
Physical Review C - Nuclear Physics | Year: 2011

We investigate the influence of the nucleon-nucleon collision profile (probability of interaction as a function of the nucleon-nucleon impact parameter) in the wounded-nucleon model and its extensions on several observables measured in relativistic heavy-ion collisions. We find that the participant eccentricity coefficient, ε *, as well as the higher harmonic coefficients, εn*, are reduced by 10-20% for midperipheral collisions when the realistic (Gaussian) profile is used, as compared to the case with the commonly used hard-sphere profile. Similarly, the multiplicity fluctuations, treated as the function of the number of wounded nucleons in one of the colliding nuclei, are reduced by 10-20%. This demonstrates that the Glauber Monte Carlo codes should necessarily use the realistic nucleon-nucleon collision profile in precision studies of these observables. Our study is relevant for hydrodynamic calculations which use the Glauber-model initial conditions. The Gaussian collision profile is built-in in glissando. © 2011 American Physical Society.


Florkowski W.,Jan Kochanowski University | Florkowski W.,Polish Academy of Sciences | Ryblewski R.,Polish Academy of Sciences
Physical Review C - Nuclear Physics | Year: 2011

We introduce a new framework of highly anisotropic hydrodynamics that includes dissipation effects. Dissipation is defined by the form of the entropy source that depends on the pressure anisotropy and vanishes for the isotropic fluid. With a simple ansatz for the entropy source obeying general physical requirements, we are led to a nonlinear equation describing the time evolution of the anisotropy in purely longitudinal boost-invariant systems. Matter that is initially highly anisotropic approaches naturally the regime of the perfect fluid. Thus, the resulting evolution agrees with the expectations about the behavior of matter produced at the early stages of relativistic heavy-ion collisions. The equilibration is identified with the processes of entropy production. © 2011 American Physical Society.


Fichet S.,São Paulo State University | Von Gersdorff G.,Pontifical Catholic University of Rio de Janeiro | Royon C.,University of Kansas | Royon C.,Polish Academy of Sciences
Physical Review Letters | Year: 2016

A slight excess has been observed in the first data of photon-photon events at the 13 TeV Large Hadron Collider that might be interpreted as a hint of physics beyond the standard model. We show that a completely model-independent measurement of the photon-photon coupling of a putative 750 GeV resonance is possible using the forward proton detectors scheduled at ATLAS and CMS. © 2016 American Physical Society.


News Article | November 10, 2016
Site: www.scientificamerican.com

Tickling is a mysterious phenomenon: this specialized form of touch is so powerful that it can send us into almost uncontrollable fits of shrieking, gasping laughter or defenseless pleas for mercy. Yet we still don’t understand how it works. Several decades ago the scientific community was surprised to discover that rats share our susceptibility to tickling, and a study published today in Science reveals more about what happens in a rat’s brain while being tickled. Researchers at Humboldt University of Berlin tickled and played with rats under different circumstances, and were able to identify an area of the brain that could be key for how rats respond. But here is the catch: This brain region was activated during tickling and play in happy rats but did not respond to tickling or play in anxious rats. Perhaps most strikingly, when scientists stimulated this brain area, rats immediately began making the same high-pitched “giggles” (above the range of human hearing) they make during tickling and play. Many mammal species are sensitive to the light, ticklish annoyance of an insect crawling across their skin, but fewer respond to gargalesis—intense, laughter-inducing tickling. Scientists once thought the effects of gargalesis were limited to highly intelligent, social species such as humans and other primates. In 1999, however, Jaak Panksepp and Jeffrey Burgdorf successfully demonstrated that tickling young rats spurs them into letting out the same ultrasonic giggles they make during play. Shimpei Ishiyama and Michael Brecht, co-authors of the present study, decided to build on this research by taking a closer look at how rat brains respond to pleasurable activities like tickling and play. They focused their attention on the somatosensory cortex, a large brain region that responds to tactile information such as touch, pain, temperature and pressure, and has different areas that correspond to different body parts. The researchers, who worked with young male rats (the most ticklish group), first wanted to confirm the previous findings. So they started tickling—the best job ever, according to Ishiyama, who carried out the experiments, and calls himself a “professional rat tickler.” The rats, as in previous studies, emitted high-pitched giggles during tickling on their bellies and backs. The researchers recorded the giggles with a special microphone and played them back at a lower, human-friendly register. They also observed that the rats began actively seeking out a tickling hand. The animals frolicked around their cages, making “joy jumps,” which, according to Brecht, is a “behavior that we see in many mammals when they’re very enthusiastic.” When the researchers made the rats anxious by placing them on high, exposed platforms under bright lights, however, the rats no longer giggled during tickling. Next, the researchers looked at brain cells in an area of the somatosensory cortex that responds to touch in the animals’ “trunk” region (the belly and back areas where they were tickling the rats). They found that during tickling, happy rats exhibited activation of brain cells representing this trunk region just before lapsing into bursts of high-pitched giggles. Anxious rats did not have as much activation in this region, even though they were being tickled in the same way, which suggests that mood affects how this brain region responds to touch. This brain region also activated while rats played with a friendly hand by chasing it around the cage. This result was particularly surprising because the somatosensory cortex is involved in processing touch. But as Ishiyama explains, during play, “nobody is touching the rat, so there is no tactile input to the body surface.” For Brecht, this finding suggests a link between tickling and play in the brain. “Maybe there are joint mechanisms or similarities between tickling and play,” he says “Maybe tickling is a trick of the brain to make animals interact with each other.” In a final experiment the researchers used an electric current to artificially activate the trunk region of the somatosensory cortex, which led to what Ishiyama describes as a “eureka moment”: Even though the rats weren’t being tickled or playing, they immediately began making the same laughter sounds they naturally make during these activities. Brecht explains that together these results create a more complete picture of the trunk region as an area of the somatosensory cortex that responds both to the physical touch of tickling and to the hands-off experience of play in that it is sensitive to mood, and may be the reason rats giggle during these activities. Other researchers in the field who were not involved in the research are enthusiastic about the findings. Diana Roccaro and Elise Wattendorf, neuroscientists at the University of Fribourg, wrote in an e-mail that the study is the first to use brain stimulation to elicit ticklish laughter, which “constitutes an outstanding result.” They add that it is particularly remarkable play behavior activates the same brain region as tickling. Piotr Popik, a neuroscientist at the Polish Academy of Sciences, also praises the work, particularly for identifying a brain region that is a probable mechanism for the high-pitched giggles observed in rats. Fausto Caruana, a neuroscientist at the University of Parma, calls the study “extraordinary,” and notes that it advances earlier work by Panksepp and Burgdorf. He emphasizes that because studying laughter in humans is very difficult, “it is extremely important to find animal models for laughter.” The study also raises new questions. Panksepp, considered a pioneer in the field, points out that we still don’t know whether this cognitive brain response involves an emotional component—what Panksepp called a “feeling message.” The big question is, “does that evoked sound in the cortex still feel good?” But what does ticklishness in rats have to do with our own reactions to tickling? “Rats and humans [diverged] maybe 100 million years ago,” Brecht says. “But the phenomenon of ticklishness is remarkably similar.” The most telling observation was one he and Ishiyama didn’t include in the paper: Rats, like humans, aren’t ticklish on their hands, but are extremely ticklish on the bottoms of their feet, he says. “It was one of those observations that really made me think that, hey, we're looking at the same thing.”


wiechowski M.,Polish Academy of Sciences | Mandziuk J.,Warsaw University of Technology
IEEE Transactions on Computational Intelligence and AI in Games | Year: 2014

The term general game playing (GGP) refers to a subfield of AI which aims at developing agents able to effectively play many games from a particular class (finite, deterministic). It is also the name of the annual competition proposed by Stanford Logic Group at Stanford University (Stanford, CA, USA), which provides a framework for testing and evaluating GGP agents. In this paper, we present our GGP player which managed to win four out of seven games in the 2012 preliminary round and advanced to the final phase. Our system (named MINI-Player) relies on a pool of playing strategies and autonomously picks the ones which seem to be best suited to a given game. The chosen strategies are combined with one another and incorporated into the upper confidence bounds applied to trees (UCT) algorithm. The effectiveness of our player is evaluated on a set of games from the 2012 GGP Competition as well as a few other, single-player games. The paper discusses the efficacy of proposed playing strategies and evaluates the mechanism of their switching. The proposed idea of dynamically assigning search strategies during play is both novel and promising. © 2013 IEEE.


Grzegorzewski P.,Polish Academy of Sciences | Grzegorzewski P.,Warsaw University of Technology
Information Sciences | Year: 2011

The problem of measuring the degree of inclusion for two intuitionistic fuzzy sets (IF-sets) is considered. Since the nature of IF-sets includes uncertainty expressed both by the membership and nonmembership functions, this very feature should be also regarded in the construction of the subsethood measures. Therefore, we suggest not a single coefficient measuring the grade of subsethood but two indicators that leave some space to the mentioned uncertainty and correspond rather to necessary and possible inclusion. © 2010 Elsevier Inc. All rights reserved.


Grzegorzewski P.,Polish Academy of Sciences | Grzegorzewski P.,Warsaw University of Technology
Information Sciences | Year: 2011

The probabilistic version of the inclusion-exclusion principle is generalized for IF-events. Two versions of the generalized formula, corresponding to different t-conorms applied for defining the union of IF-events are shown. © 2010 Elsevier Inc. All rights reserved.


Gryko D.T.,Polish Academy of Sciences | Gryko D.T.,Warsaw University of Technology | Gryko D.,Polish Academy of Sciences | Lee C.-H.,Kangwon National University
Chemical Society Reviews | Year: 2012

Dipyrranes constitute important building blocks in the synthesis of porphyrins, corroles, chlorins, calix[4]pyrroles, porphodimethenes, BODIPY dyes and dipyrrinato complexes. This tutorial review describes the overall progress made in the last twenty years in this field, mainly focusing on the most practical and useful synthetic methodologies and offers a critical comparison of various conditions reported in the literature. This review also deals with the reactivity of 5-substituted dipyrranes presenting the scope of their reactions with electrophiles. © 2012 The Royal Society of Chemistry.


Prochowicz D.,Warsaw University of Technology | Sokolowski K.,Polish Academy of Sciences | Lewinski J.,Warsaw University of Technology | Lewinski J.,Polish Academy of Sciences
Coordination Chemistry Reviews | Year: 2014

This review focuses on the synthesis, reactivity and structural chemistry of zinc hydroxides and oxides derived essentially from organozinc compounds. It demonstrates the advantages of the organometallic route to these classes of compounds that is time and atom efficient. We have surveyed the preparation of organozinc hydroxide complexes via direct hydrolysis of both R2Zn compounds and alkylzinc complexes of the type RZn(L) (where L=monoanionic, mono- or multidentate organic ligand). The variety of their molecular structures is discussed with an emphasis on how the character of zinc bonded alkyl substituents or L ligands can influence the stability and the mode of aggregation of the resulting zinc hydroxides. The section dedicated to synthetic procedures and the solid state structures of zinc oxides focuses on the following aspects: (i) zincoxane compounds; (ii) the encapsulation of ZnO species into organozinc moieties and (iii) zinc oxide complexes supported by organic ligands. Finally, utility of oxozinc carboxylates as a predesigned molecular platform for modelling of the reactivity of prototypical Zn-MOFs towards H2O and donor solvents is presented. © 2013 Elsevier B.V.


Grzegorzewski P.,Polish Academy of Sciences | Grzegorzewski P.,Warsaw University of Technology
Information Sciences | Year: 2013

Interval and trapezoidal approximation methods for fuzzy numbers have been intensively developed and examined recently. In this paper another approach to simplify fuzzy numbers, called shadowed set approximation, is suggested. Some basic properties of the proposed method is also discussed. It seems that the proposed approximation might be useful for granular computing as a tool that removes excessive precision in describing imprecise phenomena. © 2012 Elsevier Inc. All rights reserved.


Grzegorzewski P.,Polish Academy of Sciences | Grzegorzewski P.,Warsaw University of Technology
Information Sciences | Year: 2013

Such fundamental concepts of the classical theory of probability, like independence of events, the conditional probability, the law of total probability and the Bayes theorem, are generalized for IF-events. © 2013 Elsevier Inc. All rights reserved.


Gagolewski M.,Polish Academy of Sciences | Gagolewski M.,Warsaw University of Technology
Information Sciences | Year: 2013

In this paper the relationship between symmetric minitive, maxitive, and modular aggregation operators is considered. It is shown that the intersection between any two of the three discussed classes is the same. Moreover, the intersection is explicitly characterized. It turns out that the intersection contains families of aggregation operators such as OWMax, OWMin, and many generalizations of the widely-known Hirsch's h-index, often applied in scientific quality control. © 2012 Elsevier Inc. All rights reserved.


Boguta M.,Polish Academy of Sciences | Boguta M.,Warsaw University of Technology | Graczyk D.,Polish Academy of Sciences
Trends in Biochemical Sciences | Year: 2011

The synthesis of tRNA by yeast RNA polymerase III (Pol III) is regulated in response to changing environmental conditions. This control is mediated by Maf1, the global negative regulator of Pol III transcription conserved from yeast to humans. Details regarding the molecular basis of Pol III repression by Maf1 are now emerging from recently reported structural and biochemical data on Pol III and Maf1. Efficient Pol III transcription, following the shift of cells from a non-fermentable carbon source to glucose, requires phosphorylation of Maf1. One of the newly identified Maf1 kinases is the chromatin-bound casein kinase II (CK2). Current studies have allowed us to propose an innovative mechanism of Pol III regulation. We suggest that CK2-mediated phosphorylation of Maf1, occurring directly on tDNA chromatin, controls Pol III recycling. © 2011 Elsevier Ltd.


Boguta M.,Polish Academy of Sciences | Boguta M.,Warsaw University of Technology
Biochimica et Biophysica Acta - Gene Regulatory Mechanisms | Year: 2013

tRNA synthesis by yeast RNA polymerase III (Pol III) is down-regulated under growth-limiting conditions. This control is mediated by Maf1, a global negative regulator of Pol III transcription. Conserved from yeast to man, Maf1 was originally discovered in Saccharomyces cerevisiae by a genetic approach. Details regarding the molecular basis of Pol III repression by Maf1 are now emerging from the recently reported structural and biochemical data on Pol III and Maf1. The phosphorylation status of Maf1 determines its nuclear localization and interaction with the Pol III complex and several Maf1 kinases have been identified to be involved in Pol III control. Moreover, Maf1 indirectly affects tRNA maturation and decay. Here I discuss the current understanding of the mechanisms that oversee the Maf1-mediated regulation of Pol III activity and the role of Maf1 in the control of tRNA biosynthesis in yeast. This article is part of a Special Issue entitled: Transcription by Odd Pols. © 2012 Elsevier B.V.


Buraczewski A.,Warsaw University of Technology | Stobiska M.,Polish Academy of Sciences
Computer Physics Communications | Year: 2012

Macroscopically populated quantum superpositions pose a question to what extent the macroscopic world obeys quantum mechanical laws. Recently, such superpositions for light, generated by an optimal quantum cloner, have been demonstrated. They are of fundamental and technological interest. We present numerical methods useful for modeling of these states. Their properties are governed by a Gaussian hypergeometric function, which cannot be reduced to either elementary or easily tractable functions. We discuss the method of efficient computation of this function for half-integer parameters and a moderate value of its argument. We show how to dynamically estimate a cutoff for infinite sums involving this function performed over its parameters. Our algorithm exceeds double precision and is parallelizable. Depending on the experimental parameters it chooses one of the several ways of summation to achieve the best efficiency. The methods presented here can be adjusted for analysis of similar experimental schemes. © 2012 Elsevier B.V. All rights reserved.


Lewtak J.P.,Polish Academy of Sciences | Gryko D.T.,Polish Academy of Sciences | Gryko D.T.,Warsaw University of Technology
Chemical Communications | Year: 2012

Porphyrins fused with other aromatic units at the meso- and β-positions have recently emerged as a hot topic of research. Their synthesis typically starts with preparation of precursors via either Suzuki coupling of a meso-bromoporphyrin or mixed-aldehyde condensation, and is followed by oxidative aromatic coupling, often using high-valent metal reagents (DDQ/Sc(OTf)3 and Fe(iii) salts are among the most popular). In recent years, porphyrins were oxidatively coupled not only with well-known aromatic hydrocarbons such as naphthalene and pyrene, but also with more complex heterocyclic fragments, including indole, phenanthro[1,10,9,8-cdefg]carbazole and BODIPY. A subtle relationship exists between the output of intramolecular oxidative coupling and the nature of the second aromatic moiety, cation in the porphyrin cavity, oxidant, and type of remaining meso-substituent. The extension of the porphyrin chromophore leads to significant change in linear and non-linear optical properties. Very strong bathochromic shifts of absorption (λmax reaching 1.5-2 microns in some cases) and increases in two-photon absorption cross-sections are typical for these functional dyes. This journal is © The Royal Society of Chemistry 2012.


Grzybowski M.,Polish Academy of Sciences | Skonieczny K.,Polish Academy of Sciences | Butenschon H.,Leibniz University of Hanover | Gryko D.T.,Polish Academy of Sciences | Gryko D.T.,Warsaw University of Technology
Angewandte Chemie - International Edition | Year: 2013

Does the dehydrogenative coupling of aromatic compounds mediated by AlCl3 at high temperatures and also by FeCl3, MoCl 5, PIFA, or K3[Fe(CN)6] at room temperature proceed by the same mechanism in all cases? With the growing importance of the synthesis of aromatic compounds by double CH activation to give various biaryl structures, this question becomes pressing. Since some of these reactions proceed only in the presence of non-oxidizing Lewis acids and some only in the presence of certain oxidants, the authors venture the hypothesis that, depending on the electronic structure of the substrates and the nature of the "catalyst", two different mechanisms can operate. One involves the intermediacy of a radical cation and the other the formation of a sigma complex between the acid and the substrate. The goal of this Review is to encourage further mechanistic studies hopefully leading to an in-depth understanding of this phenomenon. Where is the oxidant? Although the coupling of arenes in the presence of Lewis acids has been known for some time, the differentiation between reactions in the presence of a non-oxidizing Lewis acid (Scholl reaction) and in the presence of an oxidizing Lewis acid has been lost over the years. This Review highlights the similarities and differences between these reactions, which most probably proceed by two different mechanisms. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Banaszak-Cibicka W.,University of Life Sciences in Poznań | Zmihorski M.,Polish Academy of Sciences
Journal of Insect Conservation | Year: 2012

The variability of bee communities along an urban gradient has a potentially strong impact on pollinator-plant interactions. We investigated changes in bee species richness and community composition in the city centre and suburbs of Poznań, Poland. During 2006-2008 we recorded 2,495 individuals from 104 species. The most abundant species was Andrena haemmorhoa. Other abundant species were Bombus pascuorum, Andrena vaga, Andrena nitida, Bombus terrestris. Several species appeared to be more abundant in the city centre whereas others showed an opposite tendency. We have found that the urbanized landscape can act as a filter for the bee community since some specific ecological traits facilitate colonization of the city centre. Small-bodied species that start their activity later in the season and are not solitary preferred the city centre. However, bee species diversity and richness remained stable across the urban gradient indicating some advantages of being a city dwelling bee. We suggest that a city can be a very important habitat for a diverse bee fauna and that conservation of a wide range of habitats of different urbanization levels seems to be the most suitable strategy for conservation of bee diversity in cities. © 2011 The Author(s).


Rusin T.M.,Orange Customer Service Sp. Z O.o. | Zawadzki W.,Polish Academy of Sciences
Physical Review B - Condensed Matter and Materials Physics | Year: 2013

Electrons in monolayer graphene in the presence of an electromagnetic (or electric) wave are considered theoretically. It is shown that the electron motion is a nonlinear combination of Zitterbewegung (ZB, trembling motion) resulting from the periodic potential of graphene lattice and the driving field of the wave. This complex motion is called "multimode Zitterbewegung." The theory is based on the time-dependent two-band Hamiltonian taking into account the graphene band structure and interaction with the wave. Our theoretical treatment includes the rotating-wave approximation and high-driving-frequency approximation for narrow wave packets, as well as numerical calculations for packets of arbitrary widths. Different regimes of electron motion are found, depending on relation between the ZB frequency ωZ and the driving frequency ωD for different strengths of the electron-wave interaction. Frequencies and intensities of the resulting oscillation modes are calculated. The nonlinearity of the problem results in a pronounced multimode behavior. Polarization of the medium is also calculated relating our theoretical results to observable quantities. The presence of driving wave, resulting in frequencies directly related to ωZ and increasing the decay time of oscillations, should facilitate observations of the Zitterbewegung phenomenon. © 2013 American Physical Society.


Gagolewski M.,Polish Academy of Sciences | Gagolewski M.,Warsaw University of Technology
Journal of Informetrics | Year: 2011

In this paper CITAN, the CITation ANalysis package for R statistical computing environment, is introduced. The main aim of the software is to support bibliometricians with a tool for preprocessing and cleaning bibliographic data retrieved from SciVerse Scopus and for calculating the most popular indices of scientific impact. To show the practical usability of the package, an exemplary assessment of authors publishing in the fields of scientometrics and webometrics is performed. © 2011 Elsevier Ltd.


Gagolewski M.,Polish Academy of Sciences | Gagolewski M.,Warsaw University of Technology
Journal of Informetrics | Year: 2013

In this paper we deal with the problem of aggregating numeric sequences of arbitrary length that represent e.g. citation records of scientists. Impact functions are the aggregation operators that express as a single number not only the quality of individual publications, but also their author's productivity.We examine some fundamental properties of these aggregation tools. It turns out that each impact function which always gives indisputable valuations must necessarily be trivial. Moreover, it is shown that for any set of citation records in which none is dominated by the other, we may construct an impact function that gives any a priori-established authors' ordering. Theoretically then, there is considerable room for manipulation in the hands of decision makers.We also discuss the differences between the impact function-based and the multicriteria decision making-based approach to scientific quality management, and study how the introduction of new properties of impact functions affects the assessment process. We argue that simple mathematical tools like the h- or g-index (as well as other bibliometric impact indices) may not necessarily be a good choice when it comes to assess scientific achievements. © 2013 Elsevier Ltd.


Stepien L.,Polish Academy of Sciences | Waskiewicz A.,University of Life Sciences in Poznań
Toxins | Year: 2013

Beauvericin (BEA) and enniatins (ENNs) are cyclic peptide mycotoxins produced by a wide range of fungal species, including pathogenic Fusaria. Amounts of BEA and ENNs were quantified in individual rice cultures of 58 Fusarium strains belonging to 20 species, originating from different host plant species and different geographical localities. The species identification of all strains was done on the basis of the tef-1α gene sequence. The main aim of this study was to analyze the variability of the esyn1 gene encoding the enniatin synthase, the essential enzyme of this metabolic pathway, among the BEA-and ENNs-producing genotypes. The phylogenetic analysis based on the partial sequence of the esyn1 gene clearly discriminates species producing exclusively BEA from those synthesizing mainly enniatin analogues. © 2013 by the authors; licensee MDPI, Basel, Switzerland.


Lodziana Z.,Empa - Swiss Federal Laboratories for Materials Science and Technology | Lodziana Z.,Polish Academy of Sciences
Physical Review B - Condensed Matter and Materials Physics | Year: 2010

Metal tetrahydroborates remain interesting materials as potential hydrogen storage media. While overcoming large thermodynamic stability of uni- and divalent metal borohydrides may still be challenging, very little information is available about tetrahydroborates of tri- or tetravalent metal cations. Here, we analyze basic thermodynamic and electronic properties of borohydrides of Al, Sc, Y, Ti, and Zr by means of extensive density functional calculations. We show that solid phases of these compounds can range from ionic-like structures for Y (BH4) 3 to the molecular ones of Al (BH4)3 and Zr (BH4)4. These compounds are thermodynamically unstable at room temperature with respect to their decomposition into boron and hydrogen. Their stability is explained through the experimentally observed formation of diborane being a necessary step in the decomposition path. This points out that the kinetic factors are important for analysis of the metal borohydrides stability. © 2010 The American Physical Society.


News Article | January 15, 2016
Site: phys.org

We tend to associate the milling of chemicals with old-fashioned pharmacies and the pestle and mortar. It's time to change this—recent research findings show that by the use of mechanical force, effective chemical transformations take place in solid state substances. Mechanochemical reactions have been under investigation for many years by the teams of Prof. Janusz Lewiński from the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) and the Faculty of Chemistry of Warsaw University of Technology. In their latest publication, the Warsaw researchers describe a surprisingly simple and effective method of obtaining perovskites - futuristic photovoltaic materials with a spatially complex crystal structure. "With the aid of mechanochemistry we are able to synthesize a variety of hybrid inorganic-organic functional materials with a potentially great significance for the energy sector. Our youngest 'offspring' are high quality perovskites. These compounds can be used to produce thin light-sensitive layers for high efficiency solar cells," says Prof. Lewiński. Perovskites are a large group of materials, characterized by a defined spatial crystalline structure. In nature, the perovskite naturally occurring as a mineral is calcium titanium(IV) oxide CaTiO3. Here, the calcium atoms are arranged in the corners of the cube. In the middle of each wall, there is an oxygen atom and at the centre of the cube lies a titanium atom. In other types of perovskite, the same crystalline structure can be constructed of various organic and inorganic compounds, which means titanium can be replaced by, for example, lead, tin or germanium. As a result, the properties of the perovskite can be adjusted so as to best fit the specific application—for example, in photovoltaics or catalysis, but also in the construction of superconducting electromagnets, high voltage transformers, magnetic refrigerators, magnetic field sensors, or RAM memories. At first glance, this method of producing perovskites via mechanical force, developed at the IPC PAS, looks a little like magic. "Two powders are poured into the ball mill: a white one, methylammonium iodide CH NH I, and a yellow one, lead iodide PbI . After several minutes of milling, no trace is left of the substrates. Inside the mill, there is only a homogeneous black powder: the perovskite CH NH PbI ," explains doctoral student Anna Maria Cieślak. "Hour after hour of waiting for the reaction product? Solvents? High temperatures? In our method, all this turns out to be unnecessary! We produce chemical compounds by reactions occurring only in solids at room temperature," says Dr. Daniel Prochowicz. The mechanochemically manufactured perovskites were sent to the team of Prof. Michael Graetzel from the Ecole Polytechnique de Lausanne in Switzerland, where they were used to build a new laboratory solar cell. The performance of the cell containing the perovskite with a mechanochemical pedigree proved to be more than 10 percent greater than a cell's performance with the same construction, but containing an analogous perovskite obtained by the traditional method, involving solvents. "The mechanochemical method of synthesis of perovskites is the most environmentally friendly method of producing this class of materials. Simple, efficient and fast, it is ideal for industrial applications. With full responsibility we can state that perovskites are the materials of the future, and mechanochemistry is the future of perovskites," says Prof. Lewiński. The research will be developed within GOTSolar collaborative project funded by the European Commission under the Horizon 2020 Future and Emerging Technologies action. Perovskites are not the only group of three-dimensional materials that has been produced mechanochemically by Prof. Lewiński's team. In a recent publication, the Warsaw researchers showed that by using the milling technique they can also synthesize inorganic-organic microporous metal-organic framework (MOF) materials. The free space inside these materials is the perfect place to store different chemicals, including hydrogen. Explore further: Team develops new technique for growing high-efficiency perovskite solar cells More information: D. Prochowicz et al. Mechanosynthesis of the hybrid perovskite CH NH PbI : characterization and the corresponding solar cell efficiency , J. Mater. Chem. A (2015). DOI: 10.1039/C5TA04904K


Lignin is not a pretty sight—an oily, almost black sludge. In addition, it smells much worse than it looks. Inspecting lignin, especially up close and with an unblocked nose, it's hard to believe that it is being treated as a potentially important renewable source of valuable aromatic compounds for the chemical industry. Unfortunately, despite many years of attempts by teams of chemists from all over the world, we still have not managed to develop efficient methods of converting lignin. We are a step closer to cheap solar biorefineries capable of processing lignin on an industrial scale using the new photocatalysts developed at the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw, Poland, in cooperation with the Warsaw University of Technology and the University of Cordoba. In nature, lignin is present primarily in wood, where it is responsible for wood's consistency and hardness. It is the reason why trees do not creep over the ground, but instead reach even dozens of metres up into the air. The lignin content of wood is typically from 10 to 40 percent, depending on the tree species (the species also affects the chemical composition of the lignin). In industry, lignin is produced in large quantities during the manufacture of paper, as a waste product in the wood softening process. World reserves of lignin are huge and continuing to increase. The current estimate is even 300 billion tons, so it is a raw material that is more ubiquitous than crude oil (whose reserves are approx. 230 billion tons). "From the chemical point of view lignin is a natural polymer with a very complex three-dimensional structure, constructed of, among others, many derivative aromatic compounds including those from various phenyl alcohols. This chemical richness makes lignin a potentially very interesting raw material for the chemical industry. Unfortunately, at the same time, this is its curse, because it is very difficult to develop chemical reactions that would efficiently transform lignin into a specific, single chemical compound, readily suitable for further processing," says Prof. Juan Carlos Colmenares (IPC PAS). The difficulty in processing lignin means that today it is an industrial waste product of minimum significance that is burdensome for the environment: only 2% of its reserves are further processed, and the resulting chemical compounds are, in any case, of relatively small added value. The industrial transformation of lignin into valuable chemical intermediates is advancing through the development of two new photocatalysts. Their main component is titanium dioxide TiO , deposited on a suitably selected carrier: In one case, these are nanocomposites containing iron oxide Fe O , and in the second - zeolites (aluminosilicates), with a small addition of iron. The photocatalyst with iron oxide nanocomposites was developed in close cooperation with scientists from Spain, led by Prof. Rafael Luque. "In order to ensure the most uniform coverage of the particles, the process of deposition of titanium dioxide on the medium is carried out in the presence of ultrasounds, according to a method developed at our Institute," says Prof. Colmenares. In laboratory studies at the Institute, lignin with the addition of either one or other of the photocatalysts was exposed to ultraviolet light, simulating the spectrum of incoming radiation from the Sun. Both catalysts proved surprisingly effective in the transformation of the benzyl alcohol present in the structure of lignin into a benzaldehyde, a substance used, among others, in the production of dyes and in the perfume industry. In the best case, after only four hours, up to half of the original benzyl alcohol content of lignin underwent conversion. In industrial applications, the selectivity of the reaction is also important: The more selective the reaction, the less its products are polluted by unnecessary and usually difficult-to-separate additives. It turned out that a solution that had reacted with the participation of photocatalyst contained up to 90 percent of the target substance. "In the presence of our photocatalysts, illuminated by light imitating solar radiation, the reactions took place spontaneously in lignin-based model compounds, at ordinary atmospheric pressure and at a temperature of approx. 30 degrees centigrade, thus in conditions naturally occurring in direct sunlight. This is the exact opposite of traditional refineries, which require very complicated and expensive to maintain technical infrastructure," says Prof. Colmenares. The new photocatalysts have one more advantage: They are cheap, because they do not require expensive precious metals such as palladium, and their carriers are common materials. In addition, one of the photocatalysts has magnetic properties and thus after conversion has taken place, it can be easily recovered from the solution and reused. The results obtained by the scientists from Warsaw and Cordoba are promising. However, they only apply to photocatalysts with model compounds. For the photocatalysts to effectively process real lignin—heterogeneous and often with a varying chemical composition—further studies and tests are required. The work on photocatalysts involved a group of employees of the Department of Materials Science and Engineering of the Warsaw University of Technology, headed by Prof. Krzysztof Kurzyd?owski. It is there, using advanced research techniques, that a detailed determination of the physical parameters of the new photocatalysts was carried out. More information: Juan C. Colmenares et al. Mild ultrasound-assisted synthesis of TiO2 supported on magnetic nanocomposites for selective photo-oxidation of benzyl alcohol, Applied Catalysis B: Environmental (2016). DOI: 10.1016/j.apcatb.2015.10.034


News Article | March 4, 2016
Site: phys.org

Crystals of kryptonite, a material deadly to Superman and his race, were supposed to have been created within the planet Krypton, most likely under very high pressure. The planet's name is derived from the element krypton, with the atomic number of 36, a noble gas considered to be incapable of forming stable chemical compounds. However, a publication in the journal Scientific Reports by a two-man team of theoretical chemists from the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw, Poland, predict the synthesis of a new crystalline material in which atoms of krypton would be chemically bonded to another element. "The substance we are predicting is a compound of krypton with oxygen, not nitrogen. In the convention of the comic book it should, therefore, be called 'kryptoxide,' not 'kryptonite.' So if Superman's reading this, he can stay calm—at the moment, there's no cause for panic," says Dr. Patrick Zaleski-Ejgierd (IPC PAS). "Our krypton monoxide, KrO, probably does not exist in nature. According to current knowledge, the deep interiors of planets are the only place where there is sufficient pressure for its synthesis. Oxygen does not exist there, nor does krypton." Compounds of krypton have been produced in the laboratory under cryogenic conditions. They were, however, only single, linear and small molecules of the hydrogen-carbon-krypton-carbon-hydrogen type. The Polish chemists wondered if there were conditions in which krypton would not only bond chemically with another element, but also in which it would be capable of forming an extensive and stable crystal lattice. Their search, funded by an OPUS grant from the Polish National Science Centre, involved using genetic algorithms and models built on the so-called density functional theory. In the field of solid-state physics, this theory is a basic tool for the description and study of the world of chemical molecules. "Our computer simulations suggest that crystals of krypton monoxide will be formed at a pressure in the range of 300 to 500 million atmospheres. This is a high pressure, but it can be achieved even in today's laboratories, by skillfully squeezing samples in diamond anvils," says Ph.D. student Pawel M. Lata (IPC PAS). Crystal lattices are built from atoms or molecules arranged in space in an orderly manner. The smallest repetitive fragment of such structures, the basic 'building block,' is called a unit cell. In crystals of table salt, the unit cell has the shape of a cube in which the sodium and chlorine atoms, arranged alternately, are mounted on each corner, close enough to each other that they are bound by covalent (chemical) bonds. The unit cell of krypton monoxide is cuboid with a diamond base, with krypton atoms at the corners. In addition, in the middle of the two opposite side walls, there is one atom of krypton. "Where is the oxygen? On the side walls of the unit cell, where there are five atoms of krypton, they are arranged like the dots on a dice showing the number five. Single atoms of oxygen are located between the krypton atoms, but only along the diagonal—and only along one. Thus, on each wall with five krypton atoms, there are only two atoms of oxygen. Not only that, the oxygen is not exactly on the diagonal: One of the atoms is slightly offset from it in one direction and the other atom in the other direction," says Lata. In such an idiosyncratic unit cell, each atom of oxygen is chemically bound to the two nearest adjacent atoms of krypton. Zigzag chains of Kr/OKrO/Kr will therefore pass through the crystal of krypton monoxide, forming long polymer structures. Calculations indicate that crystals of this type of krypton monoxide should have the characteristics of a semiconductor. One can assume that they will be dark, and their transparency will not be great. Theorists from the IPC PAS have also found a second, slightly less stable compound of krypton: the tetroxide KrO . This material, which probably has properties typical of a metal, has a simpler crystalline structure and could be formed at a pressure exceeding 340 million atmospheres. After formation, the two kinds of krypton oxide crystals could probably exist at a somewhat lower pressure than that required for their formation. The pressure on earth, however, is so low that on our planet these crystals would undergo degradation immediately. "Reactions occurring at extremely high pressure are almost unknown, very, very exotic chemistry. We call it 'Chemistry on the Edge.' Often, the pressures needed to perform syntheses are so gigantic that at present, there is no point in trying to produce them in laboratories. In those cases, even methods of theoretic description fail! But what is most interesting here is the non-intuitiveness. From the very first to the last step of synthesis you never know what's going to happen," says Dr. Zaleski-Ejgierd. Explore further: On titanium oxide catalyst, certain atoms and molecules flee when light appears More information: Patryk Zaleski-Ejgierd et al. Krypton oxides under pressure, Scientific Reports (2016). DOI: 10.1038/srep18938


News Article | January 16, 2016
Site: www.nanotech-now.com

Abstract: Perovskites, substances that perfectly absorb light, are the future of solar energy. The opportunity for their rapid dissemination has just increased thanks to a cheap and environmentally safe method of production of these materials, developed by chemists from Warsaw, Poland. Rather than in solutions at a high temperature, perovskites can now be synthesized by solid-state mechanochemical processes: by grinding powders. We associate the milling of chemicals less often with progress than with old-fashioned pharmacies and their inherent attributes: the pestle and mortar. It's time to change this! Recent research findings show that by the use of mechanical force, effective chemical transformations take place in solid state. Mechanochemical reactions have been under investigation for many years by the teams of Prof. Janusz Lewinski from the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) and the Faculty of Chemistry of Warsaw University of Technology. In their latest publication, the Warsaw researchers describe a surprisingly simple and effective method of obtaining perovskites - futuristic photovoltaic materials with a spatially complex crystal structure. "With the aid of mechanochemistry we are able to synthesize a variety of hybrid inorganic-organic functional materials with a potentially great significance for the energy sector. Our youngest 'offspring' are high quality perovskites. These compounds can be used to produce thin light-sensitive layers for high efficiency solar cells," says Prof. Lewinski. Perovskites are a large group of materials, characterized by a defined spatial crystalline structure. In nature, the perovskite naturally occurring as a mineral is calcium titanium(IV) oxide CaTiO3. Here the calcium atoms are arranged in the corners of the cube, in the middle of each wall there is an oxygen atom and at the centre of the cube lies a titanium atom. In other types of perovskite the same crystalline structure can be constructed of various organic and inorganic compounds, which means titanium can be replaced by, for example, lead, tin or germanium. As a result, the properties of the perovskite can be adjusted so as to best fit the specific application, for example, in photovoltaics or catalysis, but also in the construction of superconducting electromagnets, high voltage transformers, magnetic refrigerators, magnetic field sensors, or RAM memories. At first glance, the method of production of perovskites using mechanical force, developed at the IPC PAS, looks a little like magic. "Two powders are poured into the ball mill: a white one, methylammonium iodide CH3NH3I, and a yellow one, lead iodide PbI2. After several minutes of milling no trace is left of the substrates. Inside the mill there is only a homogeneous black powder: the perovskite CH3NH3PbI3," explains doctoral student Anna Maria Cieslak (IPC PAS). "Hour after hour of waiting for the reaction product? Solvents? High temperatures? In our method, all this turns out to be unnecessary! We produce chemical compounds by reactions occurring only in solids at room temperature," stresses Dr. Daniel Prochowicz (IPC PAS). The mechanochemically manufactured perovskites were sent to the team of Prof. Michael Graetzel from the Ecole Polytechnique de Lausanne in Switzerland, where they were used to build a new laboratory solar cell. The performance of the cell containing the perovskite with a mechanochemical pedigree proved to be more than 10% greater than a cell's performance with the same construction, but containing an analogous perovskite obtained by the traditional method, involving solvents. "The mechanochemical method of synthesis of perovskites is the most environmentally friendly method of producing this class of materials. Simple, efficient and fast, it is ideal for industrial applications. With full responsibility we can state: perovskites are the materials of the future, and mechanochemistry is the future of perovskites," concludes Prof. Lewinski. The described research will be developed within GOTSolar collaborative project funded by the European Commission under the Horizon 2020 Future and Emerging Technologies action. Perovskites are not the only group of three-dimensional materials that has been produced mechanochemically by Prof. Lewinski's team. In a recent publication the Warsaw researchers showed that by using the milling technique they can also synthesize inorganic-organic microporous MOF (Metal-Organic Framework) materials. The free space inside these materials is the perfect place to store different chemicals, including hydrogen. The research on mechanochemical methods for the synthesis of three-dimensional structures is funded by the TEAM and MISTRZ grants of the Foundation for Polish Science. About Institute of Physical Chemistry of the Polish Academy of Sciences The Institute of Physical Chemistry of the Polish Academy of Sciences was established in 1955 as one of the first chemical institutes of the PAS. The Institute's scientific profile is strongly related to the newest global trends in the development of physical chemistry and chemical physics. Scientific research is conducted in nine scientific departments. CHEMIPAN R&D Laboratories, operating as part of the Institute, implement, produce and commercialise specialist chemicals to be used, in particular, in agriculture and pharmaceutical industry. The Institute publishes approximately 200 original research papers annually. For more information, please click Copyright © Institute of Physical Chemistry of the Polish Academy of Sci If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


News Article | March 17, 2016
Site: www.nanotech-now.com

Home > Press > In cubosomes it's their interior that counts Abstract: Under certain conditions appropriately selected particles can form closed surfaces in liquids with surprisingly complex shapes, cutting through space by a regular network of channels. So far, we have looked at cubosomes - for this is what these spectacular three-dimensional nanostructures are called - only from the outside. Advanced theoretical modelling carried out at the Institute of Physical Chemistry of the Polish Academy of Sciences in Warsaw has allowed us to look into their interior for the first time. At first sight, it's difficult to resist the impression that they've been designed by an engineer-perfectionist, and not nature itself. We're talking about cubosomes, nanostructures with a shape that is generally cubic, riddled with holes as regular as windows in a block of flats. The sizes of cubosomes range from tens to hundreds of nanometres. So far, they have been studied mainly using electron microscopes, which made it possible to describe their external shape. However, none of the currently available experimental techniques allowed us to penetrate in detail the interior of these remarkable structures. "Where the experimenter cannot go, he sends the theorist. An effective way to see inside cubosomes proved to be theoretical modelling using computers. Our numerical calculations revealed that the internal structure of cubosomes may be much more complex than originally thought," says Dr. Wojciech Gozdz from the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw. As far as their structure is concerned, cubosomes are similar to crystals - because just as in crystals, in cubosomes a repeating basic building block, referred to as the unit cell, can be distinguished. However, the similarity is not ideal. In crystals the unit cell consists of a group of typical and always equally spaced atoms or molecules, whereas in cubosomes it is a section of appropriately formed membrane immersed in water. "Cubosomes can be constructed from a variety of unit cells corresponding to different cubic structures. A single cubosome composed of such single cells somewhat resembles a sponge. Sponges, however, have a chaotic internal structure, whilst in cubosomes it is very, very regular," describes Dr. Gozdz, adding: "A cubosome can be imagined as a closed surface. A simple example of a closed surface is a torus. However, in a torus there is only one hole, while in cubosomes there are typically from several tens to several thousands of holes." Under the appropriate conditions and employing the appropriate experimental procedures cubosomes form in a liquid medium containing amphiphilic molecules, that is, molecules where one end is hydrophobic (avoiding water), and the other is hydrophilic ( 'liking' water). In water amphiphilic molecules can form a double layer (bilayer) constructed in such a way that the hydrophilic ends are on the outside of the layer and the hydrophobic ends are directed towards its centre. Cubosomes can also be formed in ternary liquids, consisting of water, oil and amphiphilic molecules. The molecules then form not bilayers but monolayers, with their hydrophilic ends directed towards the water and hydrophobic ends towards the oil. The three-dimensional membrane formed, creating each cubosome, is closed and riddled with a regular network of tunnels. The tunnels are filled with the liquid in which the cubosome is immersed. If the solution in which the cubosome came about was two-component, the space in the cubosome enclosed by the membrane will be filled with the same liquid (in a ternary solution it would be a liquid other than that in the tunnels). Therefore, each cubosome can also be treated as a regular three-dimensional grid of channels filled with a liquid (or two liquids). Thus perceived, the cubosome becomes a crystalline structure formed of liquid 'bars' surrounded by amphiphilic molecules. In his research, Dr. Gozdz focused on cubosomes made of bilayers, since predominantly such systems have been studied experimentally and, in the future, may have many uses as drug delivery vehicles. Earlier on, attempts at a description of the shape of nanoparticles of this type were made using artificially matched mathematical functions. At the IPC PAS a model built on physical equations has been used for first time to investigate the structure of cubosomes. The results of numerical calculations have led to some interesting discoveries. "We noticed, for example, that the size of the unit cell in cubosomes may be different from the size of the single unit cell in the solution. Indeed, cubosomes may swell or shrink, in order for the resulting structure to have the least energy. If the size of the unit cell inside the cubosome remains the same as in the solution, then the cells adjacent to the walls of the cubosome may be significantly deformed," says Dr. Gozdz. The research at the IPC PAS has led to an even more surprising conclusion. Two cubosomes that are virtually identical externally can have a greatly varying internal structure! This observation is of important practical value due to one of the most important potential applications of cubosomes: the delivery of drugs in the body. Currently, liposomes are used for this purpose (these are spherical vesicles whose membrane is formed by a lipid bilayer). Compared with liposomes, cubosomes have a much richer, less uniform internal structure. A drug introduced into the cubosome's three-dimensional network of channels would be released for a longer period of time and in more precisely controlled doses. Therefore the ability to change the internal structure of cubosomes without exerting a significant influence on their exterior dimensions and shapes, discovered at the IPC PAS, opens the way to precise manipulation of the rate of release of drugs. ### The modelling of the structures of cubosomes was funded by an OPUS grant from the National Science Centre. About Institute of Physical Chemistry of the Polish Academy of Sciences The Institute of Physical Chemistry of the Polish Academy of Sciences was established in 1955 as one of the first chemical institutes of the PAS. The Institute's scientific profile is strongly related to the newest global trends in the development of physical chemistry and chemical physics. Scientific research is conducted in nine scientific departments. CHEMIPAN R&D Laboratories, operating as part of the Institute, implement, produce and commercialise specialist chemicals to be used, in particular, in agriculture and pharmaceutical industry. The Institute publishes approximately 200 original research papers annually. For more information, please click Copyright © Institute of Physical Chemistry of the Polish Academy of Sci If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


News Article | April 9, 2016
Site: www.nanotech-now.com

Home > Press > Exotic quantum effects can govern the chemistry around us Abstract: Objects of the quantum world are of a concealed and cold-blooded nature: they usually behave in a quantum manner only when they are significantly cooled and isolated from the environment. Experiments carried out by chemists and physicists from Warsaw have destroyed this simple picture. It turns out that not only does one of the most interesting quantum effects occur at room temperature and higher, but it plays a dominant role in the course of chemical reactions in solutions! We generally derive our experimental knowledge of quantum phenomena from experiments carried out using sophisticated equipment under exotic conditions: at extremely low temperatures and in a vacuum, isolating quantum objects from the disturbing influence of the environment. Scientists from the Institute of Physical Chemistry of the Polish Academy of Sciences (IPC PAS) in Warsaw, led by Prof. Jacek Waluk and Prof. Czeslaw Radzewicz's group from the Faculty of Physics, University of Warsaw (FUW), have just shown that one of the most spectacular quantum phenomena - that of tunneling - takes place even at temperatures above the boiling point of water. However, what is particularly surprising is the fact that the observed effect applies to hydrogen nuclei, which tunnel in particles floating in solution. The results of measurements leave no doubt: in the studied system, in conditions typical for our environment, tunneling turns out to be the main factor responsible for the chemical reaction! "For some time chemists have been getting used to the idea that electrons in molecules can tunnel. We have shown that in the molecule it is also possible for protons, that is, nuclei of hydrogen atoms, to tunnel. So we have proof that a basic chemical reaction can occur as a result of tunneling, and in addition in solution and at room temperature or higher," explains Prof. Waluk. In their experiments, the Warsaw researchers studied single molecules of porphycene (C20H14N4), an isomer of porphyrin. Compounds belonging to this group occur naturally, for example in human blood, where they are involved in the transport of oxygen. Their molecules are in the form of planar carbon rings with hydrogen atoms outside and four nitrogen atoms inside, arranged at the corners of a tetragon. In the space surrounded by nitrogen atoms there are two protons. These protons are able to move between the nitrogen atoms. The open question was whether they do so by moving classically, or by tunneling. Tunneling is a consequence of the probabilistic nature of quantum objects. In the classical world known to us from everyday life, an object will always with total probability be in one place, and therefore with zero probability in all others. Not so in the quantum world. When nothing disturbs the state of an elementary particle, atom or small group of them, the probability of the existence of a quantum object dissolves in space. This phenomenon leads to spectacular effects. When a man wants to surmount a wall, he has to climb it, that is, he has to strenuously increase his gravitational energy until it becomes greater than the potential barrier set by the wall. Meanwhile, the indeterminacy of the quantum object means that it can be found on the other side of the barrier, without increasing its energy - simply 'passing through'. The effect occurs much faster than ordinary transfer in space and with a probability that is greater the smaller the distance over which the object tunnels. By studying the times of the proton's jumps, it can be determined if they have moved classically or if they have tunneled. "Reality is less clear-cut. The higher our proton climbs the energy ladder of porphycene, the smaller the width of the barrier to overcome. Tunneling then becomes increasingly likely. So everything indicates that before the proton has time to climb to an energy level allowing it to classically overcome the potential barrier, it has usually tunneled anyway," explains Prof. Waluk. Climbing the potential barrier is not simple. When we supply the protons in porphycene with energy, we also induce various vibrations in the molecule itself. It turns out that among 108 possible modes of vibration in a molecule of porphycene, some increase the probability of tunneling and others decrease it. The Warsaw-based researchers, funded by grants from the Polish National Science Centre, determined the rate constants of chemical reactions involving porphycene in the temperature range from 20 to 400 Kelvin, for proton jumps occurring in the lowest energy state of the molecule, and in one of the excited vibrational states, promoting tunneling. The times of proton jumps between the nitrogen atoms were thus obtained. Experiments conducted on sets of cold, isolated particles suggested times of a few picoseconds (a millionth of one millionth of a second) - and just such times were observed in experiments in Warsaw, led by Dr. Piotr Fita and PhD student Piotr Ciacka from the FUW. Measurements show that not only does tunneling occur in porphycene, but it is responsible - even at room temperature! - for at least 80% of the proton jumps in the centres of the molecules. The dominant role of tunneling in the course of a chemical reaction and its dependence on the type of vibration of the molecule is the way to incredibly precise control of the course of chemical reactions. This sort of chemistry, known as mode-selective chemistry, has been demonstrated earlier, but at a very low temperature. The discovery of the researchers from the IPC PAS and the FUW raises hopes that in the future it will be possible to accurately control reactions taking place also under conditions typical for our environment. Chemical molecules floating in solution, previously excited in a manner that enhances their reactivity, could be introduced into a state of oscillation that significantly reduces their reactivity (or vice versa). A specific reaction, perhaps one of many taking place in the solution, could then be switched on and off on demand, by small changes in the amount of energy supplied to the molecules of a selected compound. "The tunneling of protons in molecules of porphycene in solution is spectacular proof that even at room temperature and in a dense environment a purely quantum effect can rule the course of a chemical reaction. But this is not the end of the surprises. We have a reasonable suspicion that one more exotic quantum phenomenon is involved in the movements of the two protons in porphycene, always jumping together. The world of chemistry around us would then be even more interesting. Whether this will happen - we will learn from further experiments," says Prof. Waluk. About Institute of Physical Chemistry of the Polish Academy of Sciences The Institute of Physical Chemistry of the Polish Academy of Sciences was established in 1955 as one of the first chemical institutes of the PAS. The Institute's scientific profile is strongly related to the newest global trends in the development of physical chemistry and chemical physics. Scientific research is conducted in nine scientific departments. CHEMIPAN R&D Laboratories, operating as part of the Institute, implement, produce and commercialise specialist chemicals to be used, in particular, in agriculture and pharmaceutical industry. The Institute publishes approximately 200 original research papers annually. For more information, please click Copyright © Institute of Physical Chemistry of the Polish Academy of Sci If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


Maciula R.,Polish Academy of Sciences | Szczurek A.,Polish Academy of Sciences | Szczurek A.,University of Rzeszow
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2015

We discuss four-jet production at the LHC. We calculate cross section for both single-parton scattering (SPS) using the ALPGEN code and for double-parton scattering (DPS) in leading-order collinear approach. Our results are compared with experimental data obtained recently by the CMS Collaboration. We show that the ALPGEN code relatively well describes distributions in transverse momenta and rapidity of each of the four jets ordered by their transverse momenta (leading, subleading, etc.). The SPS mechanism does not explain the distributions at large rapidity for the leading jet. The DPS mechanism improves the agreement with the experimental data in this corner of the phase space. In order to enhance the relative DPS contribution we propose to impose different cuts. The relative DPS contribution increases when decreasing the lower cut on the jet transverse momenta as well as when a low lower cut on the rapidity distance between the most remote jets is imposed. We predict very flat distribution in azimuthal angle between the most remote jets with low lower cuts on jets transverse momentum. We find phase-space corners where the DPS content is enhanced relatively to the SPS one. © 2015 The Authors.


van Hameren A.,Polish Academy of Sciences | Maciula R.,Polish Academy of Sciences | Szczurek A.,Polish Academy of Sciences | Szczurek A.,University of Rzeszow
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2015

We present first results for the 2→4 single-parton scattering gg→cc-cc- subprocess for the first time fully within the kt-factorization approach. In this calculation we have used the Kimber-Martin-Ryskin unintegrated gluon distribution which effectively includes some class of higher-order gluon emissions, and an off-shell matrix element squared calculated using recently developed techniques. The results are compared with our earlier result obtained within the collinear-factorization approach. Only slightly larger cross sections are obtained than in the case of the collinear approach. Inclusion of transverse momenta of gluons entering the hard process leads to a much stronger azimuthal decorrelation between cc and c-c- than in the collinear-factorization approach. A comparison to predictions of double parton scattering (DPS) results and the LHCb data strongly suggests that the assumption of two fully independent DPS (gg→cc-⊗gg→cc-) may be too approximate. © 2015.


Phillips K.J.H.,Natural History Museum in London | Sylwester B.,Polish Academy of Sciences | Sylwester J.,Polish Academy of Sciences
Astrophysical Journal | Year: 2015

Recent work by Bulbul et al. and Boyarsky et al. has suggested that a line feature at ∼3.5 keV in the X-ray spectra of galaxy clusters and individual galaxies seen with XMM-Newton is due to the decay of sterile neutrinos, a dark matter candidate. This identification has been criticized by Jeltema & Profumo on the grounds that model spectra suggest that atomic transitions in helium-like potassium (K xviii) and chlorine (Cl xvi) are more likely to be the emitters. Here it is pointed out that the K xviii lines have been observed in numerous solar flare spectra at high spectral resolution with the RESIK crystal spectrometer and also appear in Chandra HETG spectra of the coronally active star σ Gem. In addition, the solar flare spectra at least indicate a mean coronal potassium abundance, which is a factor between 9 and 11 higher than the solar photospheric abundance. This fact, together with the low statistical quality of the XMM-Newton spectra, completely account for the ∼3.5 keV feature and there is therefore no need to invoke a sterile neutrino interpretation of the observed line feature at ∼3.5 keV. © 2015. The American Astronomical Society. All rights reserved..


Maciula R.,Polish Academy of Sciences | Szczurek A.,University of Rzeszow
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

We discuss inclusive production of open charm in proton-proton scattering at LHC. The calculation is performed within the kt-factorization approach. Different models of unintegrated gluon distributions (UGDFs) from the literature are used. The theoretical transverse momentum as well as (pseudo)rapidity distributions of charmed mesons are compared with recent experimental data of the ATLAS, ALICE, and LHCb Collaborations. Only the calculation with Kimber-Martin-Ryskin UGDF gives results comparable to experimental ones. All other popular models of UGDF significantly underpredict experimental data. Several sources of uncertainties of the theoretical predictions are also studied in detail. In addition, we discuss correlations between D and D̄ mesons. Good description of experimental distribution in invariant mass and in relative azimuthal angle between D and D̄ mesons is achieved for the Kimber-Martin-Ryskin UGDF. The considered correlation observables measured by the LHCb experiment were not discussed in other approaches in the literature © 2013 American Physical Society.


Maciula R.,Polish Academy of Sciences | Szczurek A.,Polish Academy of Sciences | Szczurek A.,University of Rzeszow
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

We discuss production of two pairs of cc̄ in proton-proton collisions at the LHC. Both double-parton scattering (DPS) and single-parton scattering contributions are included in the analysis. Each step of DPS is calculated within a kt-factorization approach, which effectively includes some next-to-leading-order corrections. The conditions of how to identify the DPS contribution are presented. The discussed mechanism unavoidably leads to the production of pairs of mesons: DiDj (each containing c quarks) or D̄iD̄j (each containing c̄ antiquarks). We calculate corresponding production rates for different combinations of charmed mesons as well as some differential distribution for (D0D0+D̄0D̄0) production. Within large theoretical uncertainties, the predicted DPS cross section is fairly similar to the cross section measured recently by the LHCb collaboration. The best description is obtained with the Kimber-Martin-Ryskin unintegrated gluon distribution, which very well simulates higher-order corrections. The contribution of single-parton scattering, calculated in the high-energy approximation, turned out to be rather small. Finally, we emphasize the significant contribution of the DPS mechanism to inclusive charmed meson spectra measured recently by ALICE, ATLAS, and the LHCb. © 2013 American Physical Society.


Lebiedowicz P.,Polish Academy of Sciences | Szczurek A.,Polish Academy of Sciences | Szczurek A.,University of Rzeszow
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

The amplitudes for the pp→ppπ0 process applicable at high energy are discussed in detail. Both diffractive bremsstrahlung (Drell-Hiida-Deck-type model), photon-photon and photon-omega exchange mechanisms are included in the calculation. Large cross sections of the order of mb are predicted. The corresponding differential cross sections in rapidities and transverse momenta of outgoing protons and pions as well as relative azimuthal angle between outgoing protons are calculated for RHIC and LHC energies. The hadronic bremsstrahlung contributions dominate at large (forward, backward) pion rapidities. The diffractive nonresonant background contributes at small π0p invariant mass and could be therefore misinterpreted as the Roper resonance. We predict strong dependence of the slope in t (squared four-momentum transfer between ingoing and outgoing proton) on the mass of the supplementary excited π0p system. At high energies and midrapidities, the photon-photon contribution dominates over the diffractive components, however, the corresponding cross section is rather small. The photon-odderon and odderon-photon contributions are included in addition and first estimates (upper limits) of their contributions to rapidity and transverse momentum distribution of neutral pions are presented. We suggest a search for the odderon contribution at midrapidity and at p⊥,π0∼0. 5 GeV. Our predictions are ready for verification at RHIC and LHC. The bremsstrahlung mechanisms discussed here contribute also to the pp→p(nπ+) reaction. Both channels give a sizable contribution to the low-mass single diffractive cross section and must be included in extrapolating the measured experimental single diffractive cross section. © 2013 American Physical Society.


Lebiedowicz P.,Polish Academy of Sciences | Pasechnik R.,Lund University | Szczurek A.,University of Rzeszow | Szczurek A.,Polish Academy of Sciences
Nuclear Physics B | Year: 2014

We focus on exclusive production of neutral technipion π~0 in pp collisions at the LHC, i.e. on pp→ppπ~0 reaction. The dependence of the cross section on parameters of recently proposed vector-like Technicolor model is studied. Characteristic features of the differential distributions are discussed. For not too large technipion masses the diphoton decay channel has the dominant branching fraction. This is also the main reason for an enhanced production of neutral technipions in γγ-fusion reaction. We discuss potential backgrounds of the QCD and QED origin to the pp→pp(π~0→γγ) process at large invariant γγ masses. We conclude that compared to inclusive case the signal-to-background ratio in the considered exclusive reaction is very favorable which thereby could serve as a good probe for Technicolor dynamics searches at the LHC. © 2014 The Authors.


Bozek P.,Polish Academy of Sciences | Bozek P.,University of Rzeszow
Acta Physica Polonica B | Year: 2012

The hydrodynamic model for the expansion of the fireball in relativistic heavy-ion collisions is presented. Calculations using relativistic hydrodynamics of a fluid with small viscosity yield a satisfactory description of the experimental data on the particle spectra, the elliptic flow or the interferometry radii.


Zawilska J.B.,Medical University of Lódz | Zawilska J.B.,Polish Academy of Sciences
Current Drug Abuse Reviews | Year: 2011

Recently, a new class of "designer drugs" has emerged on the drug use market, known as "legal highs" or "herbal highs". They include a wide range of products, from natural plant-originated substances to synthetic compounds, that can be purchased both online and from high street retailers. "Legal highs" mimic psychoactive effects of illicit drugs of abuse. However, they are claimed to consist of compounds that are legal to sell, possess and use. Based on the spectrum of their actions on the cognitive processes, mood, and behavior "legal highs" can be classified into three basic categories: amphetamine- and ecstasy-like psychostimulants, hallucinogens, and synthetic cannabinoids ("spice"). This review surveys the current state of knowledge regarding the pharmacological properties of "legal highs". It also addresses the negative consequences of using these products. © 2011 Bentham Science Publishers Ltd.


Auszczak M.,University of Rzeszow | MacIula R.,Polish Academy of Sciences | Szczurek A.,Polish Academy of Sciences
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

We discuss production of two pairs of cc̄ within a simple formalism of double-parton scattering. Surprisingly very large cross sections, comparable to single-parton scattering single cc̄ pair production contribution, are predicted for LHC energies. Both the total inclusive cross section as a function of energy and differential distributions in rapidity and transverse momentum of charm quark/antiquark as well as some correlation distributions for √s=7TeV are shown. We have presented results for commonly used factorized Ansatz and with QCD-evolved double-parton distributions as discussed recently in the literature. The difference found between results of the naive and QCD refined approaches is found to be rather small. We discuss perspectives on how to identify the double-scattering contribution. The region of the phase space when cc, c̄c̄, cc̄ are produced with a large rapidity interval between them is potentially very promising. We have compared the results of the double- and single-scattering cc̄cc̄ pair production mechanisms. The contribution of the latter mechanism is much smaller. A good signature of the cc̄cc̄ production is e.g. a measurement of two identical D0D0 or D ̄0D ̄0 mesons in one event. Predictions for ATLAS, CMS, ALICE, and LHCb are presented. Other options of possible measurements are discussed. © 2012 American Physical Society.


Schafer W.,Polish Academy of Sciences | Szczurek A.,Polish Academy of Sciences | Szczurek A.,University of Rzeszow
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

We calculate cross sections for gg→QQ̄QQ̄ in the high-energy approximation in the mixed (longitudinal momentum fraction, impact parameter) and momentum space representations. Besides the total cross section as a function of subsystem energy also differential distributions (in quark rapidity, transverse momentum, QQ, QQ̄ invariant mass) are presented. The elementary cross section is used to calculate production of (cc̄)(cc̄) in single-parton scattering (SPS) in proton-proton collisions. We present integrated cross section as a function of proton-proton center-of-mass energy as well as differential distribution in M (cc̄)(cc̄). The results are compared with corresponding results for double-parton scattering (DPS) discussed recently in the literature. We find that the considered SPS contribution to (cc̄)(cc̄) production is at high energy (√s>5TeV) much smaller than that for DPS contribution. © 2012 American Physical Society.


Bozek P.,University of Rzeszow | Bozek P.,Polish Academy of Sciences
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2011

We calculate the elliptic flow of charged particles in Pb-Pb collisions at s=2.76 TeV in relativistic viscous hydrodynamics. The recent data of the ALICE Collaboration on the elliptic flow as function of the centrality can be very well described using the hydrodynamic expansion of a fluid with a small shear viscosity μ/s=0.08. The elliptic flow as function of the transverse momentum shows systematic deviations from a hydrodynamic behavior in the small momenta region p⊥<800 MeV. It indicates that a non-negligible contribution of non-thermalized particles from jet fragmentation is present. © 2011 Elsevier B.V.


Lebiedowicz P.,Polish Academy of Sciences | Szczurek A.,Polish Academy of Sciences | Szczurek A.,University of Rzeszow
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2010

We evaluate differential distributions for the four-body pp→ppπ+π- (and pp̄→pp̄π +π-) reaction which constitutes an irreducible background to three-body processes pp→ppM, where M are a broad resonances in the π+π- channel, e.g., M=σ, ρ0, f0(980), f2(1275), f0(1500). We include both double-diffractive contribution (both Pomeron and Reggeon exchanges) as well as pion-pion rescattering contribution. The first process dominates at higher energies and small pion-pion invariant masses while the second becomes important at lower energies and higher pion-pion invariant masses. The amplitude(s) is(are) calculated in the Regge approach. We compare our results with measured cross sections for the Intersecting Storage Ring and Fermi National Accelerator Laboratory experiments. We make predictions for future experiments at the anti-Proton ANnihilation at DArmstadt (PANDA), Relativistic Heavy Ion Collider, Tevatron, and LHC energies. Differential distributions in invariant two-pion mass, pion rapidities and transverse momenta of pions are presented. The two-dimensional distribution in (yπ+,yπ-) is particularly interesting. The higher the incident energy, the higher preference for the same-hemisphere emission of pions. The processes considered constitute a sizeable contribution to the total nucleon-nucleon cross section as well as to pion inclusive cross section. © 2010 The American Physical Society.


Liu F.,John Innes Center | Marquardt S.,John Innes Center | Lister C.,John Innes Center | Swiezewski S.,Polish Academy of Sciences | Dean C.,John Innes Center
Science | Year: 2010

Noncoding RNA is emerging as an important regulator of gene expression in many organisms. We are characterizing RNA-mediated chromatin silencing of the Arabidopsis major floral repressor gene, FLC. Through suppressor mutagenesis, we identify a requirement for CstF64 and CstF77, two conserved RNA 3′-end-processing factors, in FLC silencing. However, FLC sense transcript 3′ processing is not affected in the mutants. Instead, CstF64 and CstF77 are required for 3′ processing of FLC antisense transcripts. A specific RNA-binding protein directs their activity to a proximal antisense polyadenylation site. This targeted processing triggers localized histone demethylase activity and results in reduced FLC sense transcription. Targeted 3′ processing of antisense transcripts may be a common mechanism triggering transcriptional silencing of the corresponding sense gene.


Zalewski A.,Polish Academy of Sciences | Bartoszewicz M.,Szpitalna 2
Biological Journal of the Linnean Society | Year: 2012

Introduced species must adapt their ecology, behaviour, and morphological traits to new conditions. The successful introduction and invasive potential of a species are related to its levels of phenotypic plasticity and genetic polymorphism. We analysed changes in the body mass and length of American mink (Neovison vison) since its introduction into the Warta Mouth National Park, western Poland, in relation to diet composition and colonization progress from 1996 to 2004. Mink body mass decreased significantly during the period of population establishment within the study area, with an average decrease of 13% from 1.36 to 1.18kg in males and of 16% from 0.83 to 0.70kg in females. Diet composition varied seasonally and between consecutive years. The main prey items were mammals and fish in the cold season and birds and fish in the warm season. During the study period the proportion of mammals preyed upon increased in the cold season and decreased in the warm season. The proportion of birds preyed upon decreased over the study period, whereas the proportion of fish increased. Following introduction, the strictly aquatic portion of mink diet (fish and frogs) increased over time, whereas the proportion of large prey (large birds, muskrats, and water voles) decreased. The average yearly proportion of large prey and average-sized prey in the mink diet was significantly correlated with the mean body masses of males and females. Biogeographical variation in the body mass and length of mink was best explained by the percentage of large prey in the mink diet in both sexes, and by latitude for females. Together these results demonstrate that American mink rapidly changed their body mass in relation to local conditions. This phenotypic variability may be underpinned by phenotypic plasticity and/or by adaptation of quantitative genetic variation. The potential to rapidly change phenotypic variation in this manner is an important factor determining the negative ecological impacts of invasive species. © 2012 The Linnean Society of London.


MacIula R.,Polish Academy of Sciences | Szczurek A.,Polish Academy of Sciences | Szczurek A.,University of Rzeszow
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2014

For the first time in the literature, we discuss the production of a four-jet final state in proton-proton collisions at the LHC through the mechanism of double-parton scattering (DPS), in the context of jets with large rapidity separation. This is the region where searches for a Balitsky-Fadin-Kuraev-Lipatov (BFKL) signal are planned and/or being performed. The DPS contributions are calculated within the so-called factorized ansatz, and each step of DPS is calculated in the leading order (LO) collinear approximation. The LO pQCD calculations are shown to give a reasonably good description of recent CMS and ATLAS data on inclusive jet production; therefore, this formalism can be used to estimate the DPS effects. We demonstrate that the relative contribution (with respect to single parton scattering dijets and to the BFKL Mueller-Navelet jets) of DPS is growing at large rapidity distance between jets. This is consistent with our experience from previous studies of DPS effects in the case of open and hidden charm production. The calculated differential cross sections, as a function of rapidity distance between the jets that are the most remote in rapidity, are compared with recent results of leading logarithm and next-to-leading logarithm BFKL calculations for the Mueller-Navelet jet production at s=7TeV. The DPS contribution to widely rapidity separated jet production is carefully studied for the present energy s=7TeV, and also at the nominal LHC energy s=14TeV and in different ranges of jet transverse momenta. The differential cross section as a function of dijet transverse momenta as well as two-dimensional (pT(ymin)×pT(ymax))-plane correlations for DPS mechanism are also presented. Some ideas as to how the DPS effects could be studied in the case of four-jet production are suggested. © 2014 American Physical Society.


Pedrycz W.,University of Alberta | Pedrycz W.,Polish Academy of Sciences
Expert Systems with Applications | Year: 2010

Cognitive maps and fuzzy cognitive maps offer interesting and transparent modeling capabilities by functioning at a level of conceptual entities (nodes) and their relationships expressed either at the qualitative level of excitatory/inhibitory relationships or being further numerically quantified as encountered in fuzzy cognitive maps. While there has been a vast array of conceptual enhancements, a relatively less attention has been paid to the design of the maps especially when dealing with an algorithmic way of forming the map. The objective of this study is to offer a design strategy in which starting with experimental evidence in the form of numeric data, those data are transformed into a finite and small number of concepts (nodes) of the map and afterwards the connections of the map are estimated. We show that techniques of Granular Computing, especially fuzzy clustering are effectively used to form concepts (nodes) of well-articulated semantics. In the sequel, we show the use of global optimization in the form of Particle Swarm Optimization (PSO) to carry out calibration of the connections of the interrelationships between the nodes of the map. Numeric examples are concerned with the representation of time series and their visualization in the form of fuzzy cognitive maps. Further interpretation of the maps is also discussed. © 2010 Elsevier Ltd. All rights reserved.


Herman A.,Academy of Cosmetics and Health | Herman A.P.,Polish Academy of Sciences
Skin Pharmacology and Physiology | Year: 2013

Caffeine is being increasingly used in cosmetics due to its high biological activity and ability to penetrate the skin barrier. This alkaloid is frequently used as a hydrophilic model substance in human and animal skin penetration as well as different synthetic membrane using Franz diffusion cell experiments. The commercially available topical formulations of caffeine normally contain 3% caffeine. As for a cosmetic purpose, caffeine is used as an active compound in anti-cellulite products because it prevents excessive accumulation of fat in cells. This alkaloid stimulates the degradation of fats during lipolysis through inhibition of the phosphodiesterase activity. Caffeine has potent antioxidant properties. It helps protect cells against the UV radiation and slows down the process of photoaging of the skin. Moreover, caffeine contained in cosmetics increases the microcirculation of blood in the skin and also stimulates the growth of hair through inhibition of the 5-α-reductase activity. Copyright © 2012 S. Karger AG, Basel.


Zoladz J.A.,University School of Physical Education in Cracow | Pilc A.,Polish Academy of Sciences
Journal of Physiology and Pharmacology | Year: 2010

It is well documented that physical activity can induce a number of various stimuli which are able to enhance the strength and endurance performance of muscles. Moreover, regular physical activity can preserve or delay the appearance of several metabolic disorders in the human body. Physical exercise is also known to enhance the mood and cognitive functions of active people, although the physiological backgrounds of these effects remain unclear. In recent years, since the pioneering study in the past showed that physical activity increases the expression of the brain derived neurothophic factor (BDNF) in the rat brain, a number of studies were undertaken in order to establish the link between that neurothrophin and post-exercise enhancement of mood and cognitive functions in humans. It was recently demonstrated that physical exercise can increase plasma and/or serum BDNF concentration in humans. It was also reported that physical exercise or electrical stimulation can increase the BDNF expression in the skeletal muscles. In the present review, we report the current state of research concerning the effect of a single bout of exercise and training on the BDNF expression in the brain, in both the working muscles as well as on its concentrations in the blood. We have concluded that there may be potential benefits of the exercise-induced enhancement of the BDNF expression and release in the brain as well as in the peripheral tissues, resulting in the improvement of the functioning of the body, although this effect, especially in humans, requires more research.


Nopoush M.,Kent State University | Nopoush M.,Polish Academy of Sciences | Ryblewski R.,Kent State University | Strickland M.,Kent State University
Physical Review C - Nuclear Physics | Year: 2014

We derive a system of moment-based dynamical equations that describe the 1+1d space-time evolution of a cylindrically symmetric massive gas undergoing boost-invariant longitudinal expansion. Extending previous work, we introduce an explicit degree of freedom associated with the bulk pressure of the system. The resulting form generalizes the ellipsoidal one-particle distribution function appropriate for massless particles to massive particles. Using this generalized form, we obtain a system of partial differential equations that can be solved numerically. In order to assess the performance of this scheme, we compare the resulting anisotropic hydrodynamics solutions with the exact solution of the 0+1d Boltzmann equation in the relaxation-time approximation. We find that the inclusion of the bulk degree of freedom improves the agreement between anisotropic hydrodynamics and the exact solution for a massive gas. © 2014 American Physical Society.


Nopoush M.,Kent State University | Ryblewski R.,Polish Academy of Sciences | Strickland M.,Kent State University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

We derive the equations of motion for a system undergoing boost-invariant longitudinal and azimuthally symmetric transverse "Gubser flow" using leading-order anisotropic hydrodynamics. This is accomplished by assuming that the one-particle distribution function is ellipsoidally symmetric in the momenta conjugate to the de Sitter coordinates used to parametrize the Gubser flow. We then demonstrate that the SO(3)q symmetry in de Sitter space further constrains the anisotropy tensor to be of spheroidal form. The resulting system of two coupled ordinary differential equations for the de Sitter-space momentum scale and anisotropy parameter are solved numerically and compared to a recently obtained exact solution of the relaxation-time-approximation Boltzmann equation subject to the same flow. We show that anisotropic hydrodynamics describes the spatiotemporal evolution of the system better than all currently known dissipative hydrodynamics approaches. In addition, we prove that anisotropic hydrodynamics gives the exact solution of the relaxation-time approximation Boltzmann equation in the ideal, η/s→0, and free-streaming, η/s→?, limits. © 2015 American Physical Society.


Pedrycz W.,University of Alberta | Pedrycz W.,Polish Academy of Sciences | Song M.,University of Alberta
IEEE Transactions on Fuzzy Systems | Year: 2011

In group decision making, one strives to reconcile differences of opinions (judgments) expressed by individual members of the group. Fuzzy-decision-making mechanisms bring a great deal of flexibility. By admitting membership degrees, we are offered flexibility to exploit different aggregation mechanisms and navigate a process of interaction among decision makers to achieve an increasing level of consistency within the group. While the studies reported so far exploit more or less sophisticated ways of adjusting/transforming initial judgments (preferences) of individuals, in this paper, we bring forward a concept of information granularity. Here, information granularity is viewed as an essential asset, which offers a decision maker a tangible level of flexibility using some initial preferences conveyed by each individual that can be adjusted with the intent to reach a higher level of consensus. Our study is concerned with an extension of the well-known analytic hierarchy process to the group decision-making scenario. More specifically, the admitted level of granularity gives rise to a granular matrix of pairwise comparisons. The granular entries represented, e.g., by intervals or fuzzy sets, supply a required flexibility using the fact that we select the most suitable numeric representative of the reciprocal matrix. The proposed concept of granular reciprocal matrices is used to optimize a performance index, which comes as an additive combination of two components. The first one expresses a level of consistency of the individual pairwise comparison matrices; by exploiting the admitted level of granularity, we aim at the minimization of the corresponding inconsistency index. The second part of the performance index quantifies a level of disagreement in terms of the individual preferences. The flexibility offered by the level of granularity is used to increase the level of consensus within the group. Given an implicit nature of relationships between the realizations of the granular pairwise matrices and the values of the performance index, we consider using particle swarm optimization as an optimization vehicle. Two scenarios of allocation of granularity among decision makers are considered, namely, a uniform allocation of granularity and nonuniform distribution of granularity, where the levels of allocated granularity are also subject to optimization. A number of numeric studies are provided to illustrate an essence of the method. © 2011 IEEE.


Ryblewski R.,Polish Academy of Sciences | Strickland M.,Kent State University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

We compute dilepton production from the deconfined phase of the quark-gluon plasma using leading-order (3+1)-dimensional anisotropic hydrodynamics. The anisotropic hydrodynamics equations employed describe the full spatiotemporal evolution of the transverse temperature, spheroidal momentum-space anisotropy parameter, and the associated three-dimensional collective flow of the matter. The momentum-space anisotropy is also taken into account in the computation of the dilepton production rate, allowing for a self-consistent description of dilepton production from the quark-gluon plasma. For our final results, we present predictions for high-energy dilepton yields as a function of invariant mass, transverse momentum, and pair rapidity. We demonstrate that high-energy dilepton production is extremely sensitive to the assumed level of initial momentum-space anisotropy of the quark-gluon plasma. As a result, it may be possible to experimentally constrain the early-time momentum-space anisotropy of the quark-gluon plasma generated in relativistic heavy-ion collisions using high-energy dilepton yields. © 2015 American Physical Society.


Rusin T.M.,Ptk Centertel Sp | Zawadzki W.,Polish Academy of Sciences
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2010

One-electron 3+1 and 2+1 Dirac equations are used to calculate the motion of a relativistic electron in a vacuum in the presence of an external magnetic field. First, calculations are carried on an operator level and exact analytical results are obtained for the electron trajectories which contain both intraband frequency components, identified as the cyclotron motion, as well as interband frequency components, identified as the trembling motion, Zitterbewegung (ZB). Next, time-dependent Heisenberg operators are used for the same problem to compute average values of electron position and velocity employing Gaussian wave packets. It is shown that the presence of a magnetic field and the resulting quantization of the energy spectrum has pronounced effects on the electron ZB: it introduces intraband frequency components into the motion, influences all the frequencies, and makes the motion stationary (not decaying in time) in case of the 2+1 Dirac equation. Finally, simulations of the 2+1 Dirac equation and the resulting electron ZB in the presence of a magnetic field are proposed and described employing trapped ions and laser excitations. Using simulation parameters achieved in recent experiments of Gerritsma and coworkers, we show that the effects of the simulated magnetic field on ZB are considerable and can certainly be observed. © 2010 The American Physical Society.


Pedrycz W.,University of Alberta | Pedrycz W.,Polish Academy of Sciences | Bargiela A.,University of Nottingham
IEEE Transactions on Systems, Man, and Cybernetics, Part B: Cybernetics | Year: 2012

Clustering forms one of the most visible conceptual and algorithmic framework of developing information granules. In spite of the algorithm being used, the representation of information granules-clusters is predominantly numeric (coming in the form of prototypes, partition matrices, dendrograms, etc.). In this paper, we consider a concept of granular prototypes that generalizes the numeric representation of the clusters and, in this way, helps capture more details about the data structure. By invoking the granulation-degranulation scheme, we design granular prototypes being reflective of the structure of data to a higher extent than the representation that is provided by their numeric counterparts (prototypes). The design is formulated as an optimization problem, which is guided by the coverage criterion, meaning that we maximize the number of data for which their granular realization includes the original data. The granularity of the prototypes themselves is treated as an important design asset; hence, its allocation to the individual prototypes is optimized so that the coverage criterion becomes maximized. With this regard, several schemes of optimal allocation of information granularity are investigated, where interval-valued prototypes are formed around the already produced numeric representatives. Experimental studies are provided in which the design of granular prototypes of interval format is discussed and characterized. © 2012 IEEE.


Grant
Agency: Cordis | Branch: FP7 | Program: MC-IRSES | Phase: FP7-PEOPLE-2009-IRSES | Award Amount: 192.60K | Year: 2010

Greenhouse gases (GHG) inventories contain ineluctable uncertainties, which cause serious difficulties: (1) The compliance with commitments to reduce GHG emissions is not solved, although for most countries the emission changes agreed on under the Kyoto Protocol are often smaller than the uncertainty in their estimated emissions. (2) Neither of the emission trading systems deals with the uncertainty of emissions estimates. Thus, decreasing inventory uncertainty is of paramount importance to its credibility, quality of compliance, and proper functioning of trading systems. The project aims in improving accuracy of the inventories in countries with differentiated regions and/or high coverage by forests, where the standard inventory procedures fail in producing high accuracy inventories. The proposed solution is to use spatially distributed inventories and more detailed forest modeling. This kind of inventory has been already compiled in Lviv Polytechnic for West Ukraine. It uses multilevel mathematical models, digital maps, georeferenced databases, and appropriate software. The objective is to develop similar spatial inventory of GHG emissions for Poland. To achieve the required spatial resolution, our method relies on statistical scaling models. Systems Research Institute contributes here with the expertise in statistical modelling. These methodologies will be novel in preparing GHG inventories. Further reduction of uncertainty is expected by modification and adaptation of the methodology for Ukrainian conditions, accounting schemes and models of verified full carbon account of forest ecosystems (FCA) developed by IIASA. Information background will be represented by a hybrid land cover as system integration of all available sources of information in GIS environment; with spatial resolution 1 km. Uncertainties of the FCA are considered in details. This methodology is expected to be applied in Poland as a next step of cooperation.

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