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Benvenuti S.,Food and Environment | Bretzel F.,CNR Institute of Neuroscience
Ecological Engineering | Year: 2017

Wildflowers have an important environmental impact on rural biodiversity. Their chromatic and shape evolution, to attract pollinators, is the key to their dual benefit in terms of aesthetics and environmental functionality. Their scarcity and/or disappearance in conventional agro-ecosystems have led them to be considered as necessary for the restoration of the agro-environment. We compared the dynamics of wildflower-only and wildflower-weed communities, in outdoor boxes, in order to study the floristic evolution over the course of a three-year experiment. Four agronomic treatments were applied: seeding time, late winter cutting, summer harrowing, summer cutting after senescence. Our hypothesis was that the sustainability of the wildflower community was vulnerable to strong weed interference and that agronomic management is necessary for the long-term survival of wildflowers. The indicators used were: biomass, number of seeds in the seed bank, diversity indexes. Our results showed that the growth of the wildflowers was affected by the weeds, in terms of the biomass and seed bank accumulated. However, various agronomic disturbances, such as cutting and, to a greater extent, harrowing, maintained the balance of the floristic complexity in the wildflower-weed community. The plant equilibrium was confirmed by the Shannon, Simpson and Evenness indexes. We found that long-term wildflower sustainability is closely linked to the agronomic management. Further studies are needed to optimize the anthropic-dependent survival of such wildflower buffer areas, given the “greening” measures encouraged by the new European agricultural policy aimed at biodiversity conservation. © 2017 Elsevier B.V.

Artini C.,University of Genoa | Artini C.,CNR Institute of Neuroscience
Journal of the European Ceramic Society | Year: 2017

In this review structural features, stability issues and physical properties of the eleven interlanthanide perovskites prepared at atmospheric pressure are surveyed and discussed. Due to the reduced size difference between cations, the structure of these oxides is strongly distorted with respect to the ideal cubic case. Therefore, in structure maps they are located close to the boundary of the perovskitic stability field; an interesting correlation between stability and the Goldschmidt tolerance factor t shows that the perovskitic temperature range narrows with decreasing t. Magnetic and optical properties are strictly related to the presence of 4f electrons, that determine the existence of many discrete energy levels. Acceptor-doped LaYO3 and LaYbO3 are comparable in terms of protonic conductivity to the well known cerates, and thanks to their better chemical stability against CO2, they are a good alternative to the latter in solid oxide fuel cells. The high dielectric constant of some interlanthanide perovskites makes them interesting candidates as gate oxides in MOSFETs. © 2016 Elsevier Ltd

Raymond J.,University of Rome La Sapienza | Ricci-Tersenghi F.,CNR Institute of Neuroscience
Journal of Machine Learning Research | Year: 2017

Inference methods are often formulated as variational approximations: these approximations allow easy evaluation of statistics by marginalization or linear response, but these estimates can be inconsistent. We show that by introducing constraints on covariance, one can ensure consistency of linear response with the variational parameters, and in so doing inference of marginal probability distributions is improved. For the Bethe approximation and its generalizations, improvements are achieved with simple choices of the constraints. The approximations are presented as variational frameworks; iterative procedures related to message passing are provided for finding the minima. ©2017 Jack Raymond and Federico Ricci-Tersenghi.

Martinez S.V.,European Food Safety Authority | Siani A.,CNR Institute of Neuroscience
Trends in Food Science and Technology | Year: 2017

Background: The Health Claims Regulation entered into force in January 2007. The European Food Safety Authority (EFSA) has evaluated more than 3000 health claims since then, but EFSA's responsibilities in this area and the extent to which its scientific assessments are in accordance with the current legal framework are still not fully understood. Scope and approach: The scope of this paper is to provide insight on the use of scientific knowledge in the area of nutrition for the substantiation of health claims made on food. The reasons why a positive evaluation by EFSA may not be sufficient for the authorisation of a health claim are also discussed. Concrete examples are used to illustrate these aspects. Key findings and conclusions: How health claims are scientifically assessed by EFSA has not been fully understood by stakeholders yet. Thorough knowledge on how EU legislation translates into scientific requirements for substantiation is essential to building successful applications. Other factors which may play a role in the authorisation of a claim and which are not evaluated by EFSA, such as the legal status of the food/constituent, its safety, or the compatibility of the claim with national and international dietary recommendations, should also be considered early in the process. EFSA is committed to providing further guidance to stakeholders on how to prepare applications for authorisation by making use of its 10 years of experience on the scientific evaluation of health claims made on food. © 2017 Elsevier Ltd.

Catellani A.,CNR Institute of Neuroscience | Calzolari A.,CNR Institute of Neuroscience
Physical Review B - Condensed Matter and Materials Physics | Year: 2017

The development of plasmonic and metamaterial devices requires the research of high-performance materials alternative to standard noble metals. Renewed as a refractory stable compound for durable coatings, titanium nitride has recently been proposed as an efficient plasmonic material. Here, by using a first-principles approach, we investigate the plasmon dispersion relations of TiN bulk and we predict the effect of pressure on its optoelectronic properties. Our results explain the main features of TiN in the visible range and prove a universal scaling law which relates its mechanical and plasmonic properties as a function of pressure. Finally, we address the formation and stability of surface-plasmon polaritons at different TiN-dielectric interfaces proposed by recent experiments. The unusual combination of plasmonics and refractory features paves the way for the realization of plasmonic devices able to work at conditions not sustainable by the usual noble metals. © 2017 American Physical Society.

Dolcini F.,Polytechnic University of Turin | Dolcini F.,CNR Institute of Neuroscience
Physical Review B - Condensed Matter and Materials Physics | Year: 2017

The effects of Rashba interaction and electromagnetic field on the edge states of a two-dimensional topological insulator are investigated in a nonperturbative way. We show that the electron dynamics is equivalent to a problem of massless Dirac fermions propagating with an inhomogeneous velocity, enhanced by the Rashba profile with respect to the bare Fermi value vF. Despite the inelastic and time-reversal breaking processes induced by the electromagnetic field, no backscattering occurs without interaction. The photoexcited electron densities are explicitly obtained in terms of the electric field and the Rashba interaction, and are shown to fulfill generalized chiral anomaly equations. The case of a Gaussian electromagnetic pulse is analyzed in detail. When the photoexcitation occurs far from the Rashba region, the latter effectively acts as a "superluminal gate" boosting the photoexcited wave packet outside the light-cone determined by vF. In contrast, for an electric pulse overlapping the Rashba region, the emerging wave packets are squeezed in a manner that depends on the overlap area. The electron-electron interaction effects are also discussed, for both intraspin and interspin density-density coupling. The results suggest that Rashba interaction, often considered as an unwanted disorder effect, may be exploited to tailor the shape and the propagation time of photoexcited spin-polarized wave packets. © 2017 American Physical Society.

Rigoni M.,University of Padua | Montecucco C.,CNR Institute of Neuroscience
Journal of Neurochemistry | Year: 2017

An extraordinary property of the peripheral nervous system is that nerve terminals can regenerate after damage caused by different physical, chemical, or biological pathogens. Regeneration is the result of a complex and ill-known interplay among the nerve, the glia, the muscle, the basal lamina and, in some cases, the immune system. This phenomenon has been studied using different injury models mainly in rodents, particularly in mice, where a lesion can be produced in a chosen anatomical area. These approaches differ significantly among them for the nature of the lesion and the final outcomes. We have reviewed here the most common experimental models employed to induce motor axon injury, the relative advantages and drawbacks, and the principal read-outs used to monitor the regenerative process. Recently introduced tools for inducing reversible damage to the motor axon terminal that overcome some of the drawbacks of the more classical approaches are also discussed. Animal models have provided precious information about the cellular components involved in the regenerative process and on its electrophysiological features. Methods and tools made available recently allow one to identify and study molecules that are involved in the crosstalk among the components of the endplate. The time-course of the intercellular signaling and of the intracellular pathways activated will draw a picture of the entire process of regeneration as seen from a privileged anatomical site of observation. This is an article for the special issue XVth International Symposium on Cholinergic Mechanisms. © 2017 International Society for Neurochemistry.

Fornieri A.,CNR Institute of Neuroscience
Nature Nanotechnology | Year: 2017

Two superconductors coupled by a weak link support an equilibrium Josephson electrical current that depends on the phase difference ϕ between the superconducting condensates. Yet, when a temperature gradient is imposed across the junction, the Josephson effect manifests itself through a coherent component of the heat current that flows opposite to the thermal gradient for |ϕ| < π/2 (refs 2–4). The direction of both the Josephson charge and heat currents can be inverted by adding a π shift to ϕ. In the static electrical case, this effect has been obtained in a few systems, for example via a ferromagnetic coupling or a non-equilibrium distribution in the weak link. These structures opened new possibilities for superconducting quantum logic and ultralow-power superconducting computers. Here, we report the first experimental realization of a thermal Josephson junction whose phase bias can be controlled from 0 to π. This is obtained thanks to a superconducting quantum interferometer that allows full control of the direction of the coherent energy transfer through the junction. This possibility, in conjunction with the completely superconducting nature of our system, provides temperature modulations with an unprecedented amplitude of ∼100 mK and transfer coefficients exceeding 1 K per flux quantum at 25 mK. Then, this quantum structure represents a fundamental step towards the realization of caloritronic logic components such as thermal transistors, switches and memory devices. These elements, combined with heat interferometers and diodes, would complete the thermal conversion of the most important phase-coherent electronic devices and benefit cryogenic microcircuits requiring energy management, such as quantum computing architectures and radiation sensors. © 2017 Nature Publishing Group

Paleari S.,CNR Institute of Neuroscience
Land Use Policy | Year: 2017

Although preserving soil health is essential for sustainability, over the last decade, there has been a significant increase in soil degradation in the European Union (EU) and, based on available information, this trend will not reverse in the long run. While the Union has adopted ambitious policy objectives addressing soil threats, there is not to date an EU soil-specific legislation, but various aspects of soil protection are scattered across many EU policy areas. This paper contributes to evaluating the status of soil protection within the EU environmental legislation, by creating an inventory of the relevant provisions and analyzing their features. It emerges that soil threats are not comprehensively regulated by the EU legislator and soil protection looks like the by-product of several provisions which mainly set preventive, qualitative and non strictly binding measures. © 2017 Elsevier Ltd

Mocz P.,Harvard - Smithsonian Center for Astrophysics | Succi S.,CNR Institute of Neuroscience | Succi S.,Harvard University
Monthly Notices of the Royal Astronomical Society | Year: 2017

We revisit the integer lattice (IL) method to numerically solve the Vlasov-Poisson equations, and show that a slight variant of the method is a very easy, viable, and efficient numerical approach to study the dynamics of self-gravitating, collisionless systems. The distribution function lives in a discretized lattice phase-space, and each time-step in the simulation corresponds to a simple permutation of the lattice sites. Hence, the method is Lagrangian, conservative, and fully time-reversible. IL complements other existing methods, such as N-body/particle mesh (computationally efficient, but affected by Monte Carlo sampling noise and two-body relaxation) and finite volume (FV) direct integration schemes (expensive, accurate but diffusive). We also present improvements to the FV scheme, using a moving-mesh approach inspired by IL, to reduce numerical diffusion and the time-step criterion. Being a direct integration scheme like FV, IL is memory limited (memory requirement for a full 3D problem scales as N6, where N is the resolution per linear phase-space dimension). However, we describe a new technique for achieving N4 scaling. The method offers promise for investigating the full 6D phase-space of collisionless systems of stars and dark matter. © 2016 The Authors.

Salasnich L.,University of Padua | Salasnich L.,Consorzio Nazionale Interuniversitario per le Science Fisiche della Materia | Salasnich L.,CNR Institute of Neuroscience
Physical Review Letters | Year: 2017

For a dilute two-dimensional Bose gas the universal equation of state has a logarithmic dependence on the s-wave scattering length. Here we derive nonuniversal corrections to this equation of state, taking account of finite-range effects of the interatomic potential. Our beyond-mean-field analytical results are obtained performing dimensional regularization of divergent zero-point quantum fluctuations within the finiteerature formalism of functional integration. In particular, we find that in the grand canonical ensemble the pressure has a nonpolynomial dependence on the finite- range parameter and it is a highly nontrivial function of chemical potential and temperature. © 2017 American Physical Society.

Ciattoni A.,CNR Institute of Neuroscience | Marini A.,ICFO - Institute of Photonic Sciences | Rizza C.,CNR Institute of Neuroscience
Physical Review Letters | Year: 2017

We show that a homogeneous and isotropic slab, illuminated by a circularly polarized beam with no topological charge, produces vortices of order 2 in the opposite circularly polarized components of the reflected and transmitted fields, as a consequence of the transverse magnetic and transverse electric asymmetric response of the rotationally invariant system. In addition, in the epsilon-near-zero regime, we find that vortex generation is remarkably efficient in subwavelength thick slabs up to the paraxial regime. This physically stems from the fact that a vacuum paraxial field can excite a nonparaxial field inside an epsilon-near-zero slab since it hosts slowly varying fields over physically large portions of the bulk. Our theoretical predictions indicate that epsilon-near-zero media hold great potential as nanophotonic elements for manipulating the angular momentum of the radiation, since they are available without resorting to complicated micro- or nanofabrication processes and can operate even at very small (ultraviolet) wavelengths. © 2017 American Physical Society.

Villani G.,CNR Institute of Neuroscience
New Journal of Chemistry | Year: 2017

The G-quartet systems of DNA have been studied with a reliable quantum mechanical (QM) approach for the optimized monomeric and dimeric structures. Calculations on two Quadruplex systems, using the same QM method, but without optimization of the geometry, were performed for the first time to test the possibility of transferring, at least qualitatively, the results of the dimers in this essential biological system. Some essential properties (optimized geometries, energies and atomic charges) have been computed and discussed. To describe qualitatively and quantitatively the behavior of such systems, we have summarized these properties in the electric field and found that these kinds of systems have two different types of cavity: one where the minimum of the electric field is in the center and the other where this minimum is in one of the guanine planes. The addition of K+ or Na+ cations has been performed for one dimer and the importance of the optimization of the guanine planes was tested. Two stable positions of the cation are found for both the ions without this optimization; when the optimization of the guanines is considered, there is a stable position of the cation in the center of the cavity for the system with K+ and two stable positions of the cation for the system with the Na+, both inside the cavity and with a very small barrier. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.

Leporatti S.,CNR Institute of Neuroscience
Polymer International | Year: 2017

Halloysite nanotubes are cheap, abundant in their deposits, natural green clays with cylindrical structure having a chemical composition similar to that of kaolin. Because of their lumens, high aspect length-diameter ratio and low hydroxyl density on their surface they are readily suitable for a number of interesting applications. In this review we focus only on their use as 'nano-bazooka' drug carriers, able to shoot their cargo against major diseases. Their structure, controlled release and loading are described. We emphasize especially their possible use as novel drug delivery systems with applications in nanomedicine. © 2017 Society of Chemical Industry.

Harvey T.R.,University of Oregon | Grillo V.,University of Oregon | Grillo V.,CNR Institute of Neuroscience | Grillo V.,CNR Institute of Materials for Electronics and Magnetism | McMorran B.J.,University of Oregon
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2017

Many methods now exist to prepare free electrons into orbital-angular-momentum states, and the predicted applications of these electron states as probes of materials and scattering processes are numerous. The development of electron orbital-angular-momentum measurement techniques has lagged behind. We show that coupling between electron orbital angular momentum and a spatially varying magnetic field produces an angular-momentum-dependent focusing effect. We propose a design for an orbital-angular-momentum measurement device built on this principle. As the method of measurement is noninterferometric, the device works equally well for mixed, superposed, and pure final orbital-angular-momentum states. The energy and orbital-angular-momentum distributions of inelastically scattered electrons may be simultaneously measurable with this technique. © 2017 authors. Published by the American Physical Society.

Moctezuma-Flores M.,National Autonomous University of Mexico | Parmiggiani F.,CNR Institute of Neuroscience
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2016

A study of new-ice formation, using Cosmo-SkyMed (CSK) SAR imagery, was planned for the period February-March, 2015 over Terra Nova Bay (Antarctica). The first survey of the images showed an unexpected surface feature, i.e., a prominent ice gyre which lasted from the image of 20 February to the one of 12 March; in the image of 17 March, the ice gyre appears already completely disrupted and a well-defined polynya comes into sight. The analysis of the gyre extent in the image sequence became the object of our study. The non-linear segmentation of the set of CSK images was performed by the perceptron algorithm; this is a significant challenge because of the random nature of the speckle degradation in SAR images. The final result is a set of binary patterns providing the gyre area of each image; by this it is possible to follow the time evolution of the particular feature. © 2016 SPIE.

Lollino P.,CNR Institute of Neuroscience | Andriani G.F.,University of Bari
Rock Mechanics and Rock Engineering | Year: 2017

The strength decay that occurs in the post-peak stage, under low confinement stress, represents a key factor of the stress–strain behaviour of rocks. However, for soft rocks this issue is generally underestimated or even neglected in the solution of boundary value problems, as for example those concerning the stability of underground cavities or rocky cliffs. In these cases, the constitutive models frequently used in limit equilibrium analyses or more sophisticated numerical calculations are, respectively, rigid-plastic or elastic–perfectly plastic. In particular, most of commercial continuum-based numerical codes propose a variety of constitutive models, including elasticity, elasto-plasticity, strain-softening and elasto-viscoplasticity, which are not exhaustive in simulating the progressive failure mechanisms affecting brittle rock materials, these being characterized by material detachment and crack opening and propagation. As a consequence, a numerical coupling with mechanical joint propagation is needed to cope with fracture mechanics. Therefore, continuum-based applications that treat the simulation of the failure processes of intact rock masses at low stress levels may need the adoption of numerical techniques capable of implementing fracture mechanics and rock brittleness concepts, as it is shown in this paper. This work is aimed at highlighting, for some applications of rock mechanics, the essential role of post-peak brittleness of soft rocks by means of the application of a hybrid finite–discrete element method. This method allows for a proper simulation of the brittle rock behaviour and the related mechanism of fracture propagation. In particular, the paper presents two ideal problems, represented by a shallow underground cave and a vertical cliff, for which the evolution of the stability conditions is investigated by comparing the solutions obtained implementing different brittle material responses with those resulting from the assumption of perfectly plastic behaviour. To this purpose, a series of petrophysical and mechanical tests were conducted on samples of soft calcarenite belonging to the Calcarenite di Gravina Fm. (Apulia, Southern Italy), focusing specific attention on the post-peak behaviour of the material under three types of loading (compression, indirect tension and shear). Typical geometrical features representative of real rock engineering problems observed in Southern Italy were assumed in the problems examined. The numerical results indicate the impact of soft rock brittleness in the assessment of stability and highlight the need for the adoption of innovative numerical techniques to analyse these types of problems properly. © 2017 Springer-Verlag Wien

Coccia M.,Arizona State University | Coccia M.,CNR Institute of Neuroscience
Journal of Technology Transfer | Year: 2017

The purpose of this study is to analyze the rates of R&D investments and taxes levied on profits of firms that can optimize the labour productivity of nations. Statistical evidence, based on OECD data, reveals that (very) high rates of R&D intensity and tax on corporate profits do not maximize the labour productivity of nations. In particular, the models here suggest that the R&D intensity equal to about 2.5% and tax on corporate profits equal to 3.1% of the GDP seem to maximize the labour productivity of countries. Beyond these optimal thresholds, the labor productivity begins to decrease. These results can be explained by the curvilinear relationship between labour productivity and R&D intensity, and between labour productivity and tax on corporate profits. Some factors and environmental determinants of these results are discussed. These findings can clarify whenever possible, some sources of labor productivity and suggest a research and industrial policy of optimal rates of R&D intensity and tax on corporate profits (as percentage of GDP) directed to support competitive advantage, technological innovation and wealth creation of nations over time. © 2017 Springer Science+Business Media New York

Ragione F.D.,CNR Institute of Neuroscience | Vacca M.,CNR Institute of Neuroscience | Fioriniello S.,CNR Institute of Neuroscience | Pepe G.,IRCCS Neuromed | D'Esposito M.,CNR Institute of Neuroscience
Briefings in Functional Genomics | Year: 2016

It has been a long trip from 1992, the year of the discovery of MECP2, to the present day. What is surprising is that some of the pivotal roles of MeCP2 were already postulated at that time, such as repression of inappropriate expression from repetitive elements and the regulation of pericentric heterochromatin condensation. However, MeCP2 performs many more functions. MeCP2 is a reader of epigenetic information contained in methylated (and hydroxymethylated) DNA, moving from the 'classical' CpG doublet to the more complex view addressed by the non-CpG methylation, which is a feature of the postnatal brain. MECP2 is a transcriptional repressor, although when it forms complexes with the appropriate molecules, it can become a transcriptional activator. For all of these aspects, Rett syndrome, which is caused by MECP2 mutations, is considered a paradigmatic example of a 'chromatin disorder'. Even if the hunt for bona-fide MECP2 target genes is far from concluded today, the role of MeCP2 in the maintenance of chromatin architecture appears to be clearly established. Taking a cue from the non-scientific literature, we can firmly attest that MeCP2 is a player with 'a great future behind it'*. *V. Gassmann 'Un grande avvenire dietro le spalle'. TEA Eds. © The Author 2016. Published by Oxford University Press.

Venerando A.,University of Padua | Cesaro L.,University of Padua | Pinna L.A.,CNR Institute of Neuroscience
FEBS Journal | Year: 2017

The first phosphoprotein (casein) was discovered in 1883, yet the enzyme responsible for its phosphorylation was identified only 130 years later, in 2012. In the intervening time, especially in the last decades of the 1900s, it became evident that, far from being an oddity, phosphorylation affects the majority of eukaryotic proteins during their lifespan, and that this reaction is catalysed by the members of a large family of protein kinases, susceptible to a variety of stimuli controlling nearly every aspect of life and death. The aim of this review is to present a historical account of the main steps of this spectacular revolution, which transformed our conception of a biochemical reaction originally held as a sporadic curiosity into the master mechanism governing cell regulation, and, if it is perturbed, causing cell dysregulation. © 2017 Federation of European Biochemical Societies.

Maggi S.,CNR Institute of Neuroscience
Computers and Geotechnics | Year: 2017

The water retention curve has a key role for the hydraulic characterization of porous media. A new method, based on the differential evolution algorithm, for the determination of the characteristic parameters of several water retention models from the experimental data is proposed. We present the details of the method and its application to the calculation of water retention curves of soils. We show that our method can find the optimal model parameters without any prior information on the characteristics of the medium under investigation. The errors associated to the calculated parameters are evaluated through the random perturbation of the data. © 2017 Elsevier Ltd

De Benedictis R.,CNR Institute of Neuroscience
CEUR Workshop Proceedings | Year: 2014

The application of classical artificial intelligence techniques to realistic dynamic scenarios arises interesting challenges which require, often, the tailoring of state-of-the-art solvers to the specific domains. The introduction of a "light" and highly customizable framework allows to facilitate the way a high number of possible problems are addressed. This paper introduces the ongoing work for a novel domain-independent reasoning environment called J-TRE that takes its inspiration from Constraint Logic Programming flavoring it with Object Oriented features. The paper also addresses the customization of such an environment to a particular kind of automated planning, referred to as timeline-based, particularly suitable for complex domains. As a result, an alternative formalization of the timeline-based planning problem is proposed that allows for an interesting ability to solve both planning and scheduling problems in a uniform schema.

Mercurio F.A.,CNR Institute of Neuroscience | Leone M.,CNR Institute of Neuroscience
Current Medicinal Chemistry | Year: 2016

Background: Eph receptors play important functions in developmental processes and diseases and among them EphA2 is well known for its controversial role in cancer. Drug discovery strategies are mainly centered on EphA2 extracellular ligand-binding domain however, the receptor also contains a largely unexplored cytosolic Sam (Sterile alpha motif) domain at the C-terminus. EphA2-Sam binds the Sam domain from the lipid phosphatase Ship2 and the first Sam domain of Odin. Sam-Sam interactions may be important to regulate ligand-induced receptor endocytosis and degradation i.e., processes that could be engaged against tumor malignancy. Methods: We critically analyzed literature related to a) Eph receptors with particular emphasis on EphA2 and its role in cancer, b) Sam domains, c) heterotypic Sam-Sam interactions involving EphA2-Sam. Results: While literature data indicate that binding of EphA2-Sam to Ship2-Sam should largely generate pro-oncogenic effects in cancer cells, the correlation between EphA2- Sam/Odin-Sam1 complex and the disease is unclear. Recently a few linear peptides encompassing binding interfaces from either Ship2-Sam and Odin-Sam1 have been characterized but failed to efficiently block heterotypic Sam-Sam interactions involving EphA2-Sam due to the lack of a native like fold. Conclusion: Molecule antagonists of heterotypic EphA2-Sam associations could work as potential anticancer agents or be implemented as tools to further clarify receptor functions and eventually validate its role as a novel target in the field of anti-cancer drug discovery. Due to the failure of linear peptides there is a crucial need for novel approaches, based on cyclic or helical molecules, to target Sam-Sam interfaces. © 2016 Bentham Science Publishers.

Giazotto F.,CNR Institute of Neuroscience | Bergeret F.S.,Donostia International Physics Center
Applied Physics Letters | Year: 2013

We theoretically investigate heat transport in hybrid normal metal-superconductor (NS) nanojunctions focusing on the effect of thermal rectification. We show that the heat diode effect in the junction strongly depends on the transmissivity and the nature of the NS contact. Thermal rectification efficiency can reach up to ∼123% for a fully transmissive ballistic junction and up to 84% in diffusive NS contacts. Both values exceed the rectification efficiency of a NIS tunnel junction (I stands for an insulator) by a factor close to ∼5 and ∼3, respectively. Furthermore, we show that for NS point-contacts with low transmissivity, inversion of the heat diode effect can take place. Our results could prove useful for tailoring heat management at the nanoscale, and for mastering thermal flux propagation in low-temperature caloritronic nanocircuitry. © 2013 AIP Publishing LLC.

Albertazzi L.,TU Eindhoven | Albertazzi L.,CNR Institute of Neuroscience | Bendikov M.,Weizmann Institute of Science | Baran P.S.,Scripps Research Institute
Journal of the American Chemical Society | Year: 2012

The detection of chemical or biological analytes upon molecular reactions relies increasingly on fluorescence methods, and there is a demand for more sensitive, more specific, and more versatile fluorescent molecules. We have designed long wavelength fluorogenic probes with a turn-ON mechanism based on a donor-two-acceptor π-electron system that can undergo an internal charge transfer to form new fluorochromes with longer π-electron systems. Several latent donors and multiple acceptor molecules were incorporated into the probe modular structure to generate versatile dye compounds. This new library of dyes had fluorescence emission in the near-infrared (NIR) region. Computational studies reproduced the observed experimental trends well and suggest factors responsible for high fluorescence of the donor-two-acceptor active form and the low fluorescence observed from the latent form. Confocal images of HeLa cells indicate a lysosomal penetration pathway of a selected dye. The ability of these dyes to emit NIR fluorescence through a turn-ON activation mechanism makes them promising candidate probes for in vivo imaging applications. © 2012 American Chemical Society.

Alessandrini A.,CNR Institute of Neuroscience | Facci P.,CNR Institute of Biophysics
Soft Matter | Year: 2014

We review the capabilities of Atomic Force Microscopy (AFM) in the study of phase transitions in Supported Lipid Bilayers (SLBs). AFM represents a powerful technique to cover the resolution range not available to fluorescence imaging techniques and where spectroscopic data suggest what the relevant lateral scale for domain formation might be. Phase transitions of lipid bilayers involve the formation of domains characterized by different heights with respect to the surrounding phase and are therefore easily identified by AFM in liquid solution once the bilayer is confined to a flat surface. Even if not endowed with high time resolution, AFM allows light to be shed on some aspects related to lipid phase transitions in the case of both a single lipid component and lipid mixtures containing sterols also. We discuss here the obtained results in light of the peculiarities of supported lipid bilayer model systems. © the Partner Organisations 2014.

A study was conducted on 5 different plots to compare the performance of traditional and mechanized operations. The test plots were considered representative of conifer plantations in the Alps and were split in two halves, each harvested with a different technology level. During harvesting, researchers recorded all work time, volume output and resource usage of all ongoing operations on a daily basis. These data were used to calculate harvesting cost, labour productivity and energy consumption. As an average, the application of modern harvesting technology allowed reducing harvesting cost by a half, shrinking it to 24.8€m -3 from the original 50.1€m -3. However, the rates actually paid by the forest owner were not significantly different, and were in the range of 40€m -3. This may indicate that the mechanized firm and the traditional firm internalize a significant portion of the profits and the losses, respectively. Such instance may depend on the virtual oligopoly enjoyed by mechanized firms and on the capacity of traditional firms to use resources available at marginal costs. Mechanization allows multiplying operator productivity and for this reason achieves an overwhelming superiority over traditional technology, which makes it a better choice even when utilization rates and labour cost are comparatively low. A break-even between the two technology levels is obtained only when the utilization rate and labour cost are not higher than 300hyear -1 and 8€h -1 respectively. Furthermore, the introduction of modern machinery does not result in a higher consumption of fossil energy per unit of product. A major technology shift may be occurring in Italian forest operations, as it did occur further north in recent years. © 2011.

Lionetti V.,Sant'Anna School of Advanced Studies | Lionetti V.,CNR Institute of Neuroscience | Stanley W.C.,University of Maryland, Baltimore | Recchia F.A.,Sant'Anna School of Advanced Studies | And 2 more authors.
Cardiovascular Research | Year: 2011

In the advanced stages of heart failure, many key enzymes involved in myocardial energy substrate metabolism display various degrees of down-regulation. The net effect of the altered metabolic phenotype consists of reduced cardiac fatty oxidation, increased glycolysis and glucose oxidation, and rigidity of the metabolic response to changes in workload. Is this metabolic shift an adaptive mechanism that protects the heart or a maladaptive process that accelerates structural and functional derangement? The question remains open; however, the metabolic remodelling of the failing heart has induced a number of investigators to test the hypothesis that pharmacological modulation of myocardial substrate utilization might prove therapeutically advantageous. The present review addresses the effects of indirect and direct modulators of fatty acid (FA) oxidation, which are the best pharmacological agents available to date for 'metabolic therapy' of failing hearts. Evidence for the efficacy of therapeutic strategies based on modulators of FA metabolism is mixed, pointing to the possibility that the molecular/biochemical alterations induced by these pharmacological agents are more complex than originally thought. Much remains to be understood; however, the beneficial effects of molecules such as perhexiline and trimetazidine in small clinical trials indicate that this promising therapeutic strategy is worthy of further pursuit. © 2010 The Author.

Papanikolaou S.,Cornell University | Bohn F.,Federal University of Rio Grande do Norte | Bohn F.,Brazilian Center for Research in Physics (CBPF) | Sommer R.L.,Brazilian Center for Research in Physics (CBPF) | And 5 more authors.
Nature Physics | Year: 2011

The study of critical phenomena and universal power laws has been one of the central advances in statistical mechanicsduring the second half of the past century, explaining traditional thermodynamic critical points1, avalanche behaviour near depinning transitions2,3 and a wide variety of other phenomena4. Scaling, universality and the renormalization group claim to predict all behaviour at long length and timescales asymptotically close to critical points. In most cases, the comparison between theory and experiments has been limited to the evaluation of the critical exponents of the power-law distributions predicted at criticality. An excellent area for investigating scaling phenomena is provided by systems exhibiting crackling noise, such as the Barkhausen effect in ferromagnetic materials 5. Here we go beyond power-law scaling and focus on the average functional form of the noise emitted by avalanches-the average temporal avalanche shape4. By analysing thin permalloy films and improving the data analysis methods, our experiments become quantitatively consistent with our calculation for the multivariable scaling function in the presence of a demagnetizing field and finite field-ramp rate. © 2011 Macmillan Publishers Limited. All rights reserved.

Poccia N.,University of Rome La Sapienza | Fratini M.,University of Rome La Sapienza | Ricci A.,University of Rome La Sapienza | Campi G.,CNR Institute of Neuroscience | And 5 more authors.
Nature Materials | Year: 2011

The disposition of defects in metal oxides is a key attribute exploited for applications from fuel cells and catalysts to superconducting devices and memristors. The most typical defects are mobile excess oxygens and oxygen vacancies, which can be manipulated by a variety of thermal protocols as well as optical and d.c. electric fields. Here we report the X-ray writing of high-quality superconducting regions, derived from defect ordering1, in the superoxygenated layered cuprate, La2CuO4+y. Irradiation of a poor superconductor prepared by rapid thermal quenching results first in the growth of ordered regions, with an enhancement of superconductivity becoming visible only after a waiting time, as is characteristic of other systems such as ferroelectrics2,3, where strain must be accommodated for order to become extended. However, in La 2CuO4+y, we are able to resolve all aspects of the growth of (oxygen) intercalant order, including an extraordinary excursion from low to high and back to low anisotropy of the ordered regions. We can also clearly associate the onset of high-quality superconductivity with defect ordering in two dimensions. Additional experiments with small beams demonstrate a photoresist-free, single-step strategy for writing functional materials. © 2011 Macmillan Publishers Limited. All rights reserved.

Oddou-Muratorio S.,French National Institute for Agricultural Research | Klein E.K.,French National Institute for Agricultural Research | Vendramin G.G.,CNR Institute of Neuroscience | Fady B.,French National Institute for Agricultural Research
Molecular Ecology | Year: 2011

Trees long lifespan, long-distance dispersal abilities and high year-to-year variability in fecundity are thought to have pervasive consequences for the demographic and genetic structure of recruited seedlings. However, we still lack experimental studies quantifying the respective roles of spatial processes such as restricted seed and pollen dispersal and temporal processes such as mast seeding on patterns of regeneration. Dynamics of European beech (Fagus sylvatica) seedling recruitment was monitored in three plots from 2004 to 2006. Six polymorphic microsatellite genetic markers were used to characterize seedlings and their potential parents in a 7.2-ha stand. These seedlings were shown to result from 12 years of recruitment, with one predominant year of seedling recruitment in 2002 and several years without significant recruitment. Using a spatially explicit mating model based on parentage assignment, short average dispersal distances for seed (δ s = 10.9 m) and pollen (43.7 m < δ p < 57.3 m) were found, but there was also a non-negligible immigration rate from outside the plot (m s = 20.5%; 71.6% < m p < 77.9%). Hierarchical analyses of seedling genetic structure showed that (i) most of the genetic variation was within plots; (ii) the genetic differentiation among seedling plots was significant (F ST = 2.6%) while (iii) there was no effect of year-to-year seed rain variation on genetic structure. In addition, no significant effect of genetic structure on mortality was detected. The consequences of these results for the prediction of population dynamics at ecological timescales are discussed. © 2011 Blackwell Publishing Ltd.

Delye C.,French National Institute for Agricultural Research | Pernin F.,French National Institute for Agricultural Research | Scarabel L.,CNR Institute of Neuroscience
Plant Science | Year: 2011

We investigated the diversity of mechanisms conferring resistance to herbicides inhibiting acetolactate synthase (ALS) in corn poppy (Papaver rhoeas L.) and the processes underlying the selection for resistance. Six mutant ALS alleles, Arg 197, His 197, Leu 197, Ser 197, Thr 197 and Leu 574 were identified in five Italian populations. Different alleles were found in a same population or a same plant. Comparison of individual plant phenotype (herbicide sensitivity) and genotype (amino-acid substitution(s) at codon 197) showed that all mutant ALS alleles conferred dominant resistance to the field rate of the sulfonylurea tribenuron and moderate or no resistance to the field rate of the triazolopyrimidine florasulam. Depending on the allele, dominant or partially dominant resistance to the field rate of the imidazolinone imazamox was observed. Putative non-target-site resistance mechanisms were also likely present in the populations investigated. The derived Cleaved Amplified Polymorphic Sequence assays targeting ALS codons crucial for herbicide sensitivity developed in this work will facilitate the detection of resistance due to mutant ALS alleles. Nucleotide variation around codon 197 indicated that mutant ALS alleles evolved by multiple, independent appearances. Resistance to ALS inhibitors in P. rhoeas clearly evolved by redundant evolution of a set of mutant ALS alleles and likely of non-target-site mechanisms. © 2010 Elsevier Ireland Ltd.

Bonora S.,CNR Institute of Neuroscience | Zawadzki R.J.,University of California at Davis
Optics Letters | Year: 2013

We present a method for optimization of optical coherence tomography images using wavefront sensorless adaptive optics. The method consists of systematic adjustment of the coefficients of a subset of the orthogonal Zernike bases and application of the resulting shapes to a deformable mirror, while optimizing using image sharpness as a merit function. We demonstrate that this technique can compensate for aberrations induced by trial lenses. Measurements of the point spread function before and after compensation demonstrate near diffraction limit imaging. © 2013 Optical Society of America.

Jian Y.,Simon Fraser University | Xu J.,Simon Fraser University | Gradowski M.A.,Simon Fraser University | Bonora S.,CNR Institute of Neuroscience | And 2 more authors.
Biomedical Optics Express | Year: 2014

We present wavefront sensorless adaptive optics (WSAO) Fourier domain optical coherence tomography (FD-OCT) for in vivo small animal retinal imaging. WSAO is attractive especially for mouse retinal imaging because it simplifies optical design and eliminates the need for wavefront sensing, which is difficult in the small animal eye. GPU accelerated processing of the OCT data permitted real-time extraction of image quality metrics (intensity) for arbitrarily selected retinal layers to be optimized. Modal control of a commercially available segmented deformable mirror (IrisAO Inc.) provided rapid convergence using a sequential search algorithm. Image quality improvements with WSAO OCT are presented for both pigmented and albino mouse retinal data, acquired in vivo. © 2014 Optical Society of America.

Vincenti M.A.,Aegis Inc | De Ceglia D.,Aegis Inc | Ciattoni A.,CNR Institute of Neuroscience | Scalora M.,Charles wden Research Center
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011

We show an alternative path to efficient second- and third-harmonic generation in proximity of the zero crossing points of the dielectric permittivity in conjunction with low absorption. Under these circumstances, any material, either natural or artificial, will show similar degrees of field enhancement followed by strong harmonic generation, without resorting to any resonant mechanism. The results presented in this paper provide a general demonstration of the potential that the zero-crossing-point condition holds for nonlinear optical phenomena. We investigate a generic Lorentz medium and demonstrate that a singularity-driven enhancement of the electric field may be achieved even in extremely thin layers of material. We also discuss the role of nonlinear surface sources in a realistic scenario where a 20-nm layer of CaF 2 is excited at 21 μm, where ε ∼ 0. Finally, we show similar behavior in an artificial composite material that includes absorbing dyes in the visible range, provide a general tool for the improvement of harmonic generation using the ε ∼ 0 condition, and illustrate that this singularity-driven enhancement of the field lowers the thresholds for a plethora of nonlinear optical phenomena. ©2011 American Physical Society.

O'Callaghan C.,CNR Institute of Neuroscience | O'Callaghan C.,University of New South Wales | Bertoux M.,University Pierre and Marie Curie | Hornberger M.,CNR Institute of Neuroscience | Hornberger M.,University of New South Wales
Journal of Neurology, Neurosurgery and Psychiatry | Year: 2014

Investigations of cognitive and behavioural changes in neurodegeneration have been mostly focussed on how cortical changes can explain these symptoms. In the proposed review, we will argue that the striatum has been overlooked as a critical nexus in understanding the generation of such symptoms. Although the striatum is historically more associated with motor dysfunction, there is increasing evidence from functional neuroimaging studies in the healthy that striatal regions modulate behaviour and cognition. This should not be surprising, as the striatum has strong anatomical connections to many cortical regions including the frontal, temporal and insula lobes, as well as some subcortical regions (amygdala, hippocampus). To date, however, it is largely unclear to what extent striatal regions are affected in many neurodegenerative conditions - and if so, how striatal dysfunction can potentially influence cognition and behaviour. The proposed review will examine the existing evidence of striatal changes across selected neurodegenerative conditions (Parkinson's disease, progressive supranuclear palsy, Huntington's disease, motor neuron disease, frontotemporal dementia and Alzheimer's disease), and will document their link with the cognitive and behavioural impairments observed. Thus, by reviewing the varying degrees of cortical and striatal changes in these conditions, we can start outlining the contributions of the striatal nexus to cognitive and behavioural symptoms. In turn, this knowledge will inform future studies investigating corticostriatal networks and also diagnostic strategies, disease management and future therapeutics of neurodegenerative conditions.

Zanotto S.,CNR Institute of Neuroscience | Zanotto S.,Polytechnic of Milan | Mezzapesa F.P.,CNR Institute for Photonics and Nanotechnologies | Bianco F.,CNR Institute of Neuroscience | And 8 more authors.
Nature Physics | Year: 2014

The ability to drive a system with an external input is a fundamental aspect of light-matter interaction. The key concept in many photonic applications is the a critical couplinga condition: at criticality, all the energy fed to the system is dissipated within the system itself. Although this idea was crucial to enhance the efficiency of many devices, it was never considered in the context of systems operating in a non-perturbative regime. In this so-called strong-coupling regime, the matter and light degrees of freedom are mixed into dressed states, leading to new eigenstates called polaritons. Here we demonstrate that the strong-coupling regime and the critical coupling condition can coexist; in such a strong critical coupling situation, all the incoming energy is converted into polaritons. A general semiclassical theory reveals that such a situation corresponds to a special curve in the phase diagram of the coupled light-matter oscillators. In the case of a system with two radiating ports, the phenomenology shown is that of coherent perfect absorption (CPA; refs,), which is then naturally understood in the framework of critical coupling. Most importantly, we experimentally verify polaritonic CPA in a semiconductor-based intersubband-polariton photonic crystal resonator. This result opens new avenues in polariton physics, making it possible to control the pumping efficiency of a system independent of the energy exchange rate between the electromagnetic field and the material transition. © 2014 Macmillan Publishers Limited.

Hassanshahian M.,Shahid Bahonar University of Kerman | Tebyanian H.,Shahid Bahonar University of Kerman | Cappello S.,CNR Institute of Neuroscience
Marine Pollution Bulletin | Year: 2012

Among six crude oil-degrading yeasts that were isolated from an oil-polluted area in the Persian Gulf, two yeast strains showed high degradation activity of aliphatic hydrocarbons. From an analysis of 18S rRNA sequences and biochemical characteristics, these strains were identified as Yarrowia lipolytica strains PG-20 and PG-32. Gas Chromatography (GC) analysis of the crude oil remaining in the culture medium after 1. week at 30. °C showed that the strains PG-20 and PG-32 degraded 68% and 58% of crude oil, respectively. The optimal growth condition and biodegradation of hydrocarbons was in ONR medium with an acidic pH (pH. 5). These two strains may degrade aliphatic hydrocarbons more efficiently than aromatic hydrocarbons, although strain PG-20 had better degradation than strain PG-32. The two Y. lipolytica strains reduce surface tension when cultured on hydrocarbon substrates (1% v/v). These strains showed a cell surface hydrophobicity higher than 70%. These results suggested that Y. lipolytica strains PG-20 and PG-32 have high crude oil degrading activity due to their high emulsifying activity and cell hydrophobicity. In conclusion, these yeast strains can be useful for the bioremediation process in the Persian Gulf and decreasing oil pollution in this marine ecosystem. © 2012 Elsevier Ltd.

Mauri P.,CNR Institute of Neuroscience
Journal of Chromatography A | Year: 2015

The purpose of clinical proteomics is to characterise protein profiles of a plethora of diseases with the aim of finding specific biomarkers. These are particularly valuable for early diagnosis, and represent key molecules suitable to elucidate pathogenic mechanisms. Samples deriving from patients (i.e. blood, urine, cerebrospinal fluid, biopsies) are the sources for clinical proteomics. Due to the complexity of the extracted samples their direct analysis is unachievable. Any analytical clinical proteomics study should start with the choice of the optimal combination of strategies with respect to both sample preparations and MS approaches. Protein or peptide fractionation (off-line or on-line) is essential to reduce complexity of biological samples and to achieve the most complete and reproducible analysis. The aim of this review is to introduce the readers to a functional range of strategies to help scientists in their proteomics set up. In particular, the separation approaches of proteins or peptides (both gel-based and gel-free) are reviewed with special attention paid to their advantages and limitations, and to the different liquid chromatography techniques used to peptide fractionation after protein enzymatic digestion and before their detection. Finally, the role of mass spectrometry (MS) for protein identification and quantification is discussed including emerging MS data acquisition strategies. © 2014 Elsevier B.V.

Campbell S.,Queen's University of Belfast | De Chiara G.,Queen's University of Belfast | Paternostro M.,Queen's University of Belfast | Palma G.M.,CNR Institute of Neuroscience | And 2 more authors.
Physical Review Letters | Year: 2015

We study transitionless quantum driving in an infinite-range many-body system described by the Lipkin-Meshkov-Glick model. Despite the correlation length being always infinite the closing of the gap at the critical point makes the driving Hamiltonian of increasing complexity also in this case. To this aim we develop a hybrid strategy combining a shortcut to adiabaticity and optimal control that allows us to achieve remarkably good performance in suppressing the defect production across the phase transition. © 2015 American Physical Society.

Govoni M.,University of Modena and Reggio Emilia | Ossicini S.,CNR Institute of Neuroscience
Nature Photonics | Year: 2012

The conversion of solar radiation into electric current with high efficiency is one of the most important topics of modern scientific research, as it holds great potential as a source of clean and renewable energy. Exploitation of interaction between nanocrystals seems to be a promising route to the establishment of third-generation photovoltaics. Here, we adopt a fully ab initio scheme to estimate the role of nanoparticle interplay in the carrier multiplication dynamics of interacting silicon nanocrystals. Energy and charge transfer-based carrier multiplication events are studied as a function of nanocrystal separation, demonstrating the benefits induced by the wavefunction sharing regime. We prove the relevance of these recombinative mechanisms for photovoltaic applications in the case of silicon nanocrystals arranged in dense arrays, quantifying at an atomic scale which conditions maximize the outcome. © 2012 Macmillan Publishers Limited. All rights reserved.

Karimi E.,University of Naples Federico II | Marrucci L.,University of Naples Federico II | Marrucci L.,CNR Institute of Neuroscience | Grillo V.,CNR Institute of Neuroscience | And 2 more authors.
Physical Review Letters | Year: 2012

We propose the design of a space-variant Wien filter for electron beams that induces a spin half-turn and converts the corresponding spin angular momentum variation into orbital angular momentum of the beam itself by exploiting a geometrical phase arising in the spin manipulation. When applied to a spatially coherent input spin-polarized electron beam, such a device can generate an electron vortex beam, carrying orbital angular momentum. When applied to an unpolarized input beam, the proposed device, in combination with a suitable diffraction element, can act as a very effective spin-polarization filter. The same approach can also be applied to neutron or atom beams. © 2012 American Physical Society.

Celi S.,Sant'Anna School of Advanced Studies | Celi S.,CNR Institute of Neuroscience | Berti S.,CNR Institute of Neuroscience
European Journal of Cardio-thoracic Surgery | Year: 2014

Objectives: In clinical practice, maximum diameter is used as a criterion to estimate aneurysm-rupture risk; however, it is only a general indicator and its value becomes difficult to estimate in the thoracic segment. Improved understanding of aortic aneurysm complexity and biomechanics is needed to achieve advancements in surgical repair techniques. The objective of this study was to determine the maximum wall stress by using imaging-derived data and a specific probabilistic design integrated into finite element (FE) analysis. Methods: Computed tomography images of thoracic aortic aneurysms from our database were analysed and the main morphological features were identified by means of a specific automatic routine. Morphological data were used to develop an idealized finite element library of thoracic aortic arch models. Sensitivity analyses were performed by using the geometrical parameters as input variables for a statistical wall stress assessment. Numerical results were compared with those obtained from deterministic analysis on patient-specific three-dimensional reconstructions. Results: The results showed that in small aneurysms, wall stress values similar to those of large aneurysms can be obtained if a significant eccentricity is achieved. In small aneurysms, the peak stress is primarily affected by the eccentricity of the bulge [correlation coefficient (CC) = 0.86], while for diameters in the range of 50-60 mm, the CC is 0.43 for the eccentricity and 0.72 for the maximum diameter. Conclusions: The stress distribution in small aneurysms may contribute to the pathogenesis of aortic rupture and dissections. Our method can provide a novel and efficient procedure for generating computational models to estimate the wall stress in a comparative multivariate manner. © The Author 2013. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Casati G.,University of Insubria | Casati G.,CNR Institute of Neuroscience | Prosen T.,University of Ljubljana
Physical Review Letters | Year: 2012

We introduce a new family of billiards which break time reversal symmetry in spite of having piece-wise straight trajectories. We show that our billiards preserve the ergodic and mixing properties of conventional billiards while they may turn into exponential the power law decay of correlations characteristic of Sinai type billiards. Such billiards can be implemented by squeezing the transverse magnetic field along lines or along one-dimensional manifolds. © 2012 American Physical Society.

Casentini B.,CNR Institute of Neuroscience | Hug S.J.,Eawag - Swiss Federal Institute of Aquatic Science and Technology | Nikolaidis N.P.,Technical University of Crete
Science of the Total Environment | Year: 2011

The accumulation of arsenic in soils and food crops due to the use of arsenic contaminated groundwater for irrigation has created worldwide concern. In the Chalkidiki prefecture in Northern Greece, groundwater As reach levels above 1000. μg/L within the Nea Triglia geothermal area. While this groundwater is no longer used for drinking, it represents the sole source for irrigation.This paper provides a first assessment of the spatial extent of As accumulation and of As mobility during rainfall and irrigation periods. Arsenic content in sampled soils ranged from 20 to 513mg/kg inside to 5-66mg/kg outside the geothermal area. Around irrigation sprinklers, high As concentrations extended horizontally to distances of at least 1.5m, and to 50cm in depth. During simulated rain events in soil columns (pH=5, 0μg As/L), accumulated As was quite mobile, resulting in porewater As concentrations of 500-1500μg/L and exposing plant roots to high As(V) concentrations. In experiments with irrigation water (pH=7.5, 1500μg As/L), As was strongly retained (50.5-99.5%) by the majority of the soils. Uncontaminated soils (<30mg As/kg) kept soil porewater As concentrations to below 50μg/L. An estimated retardation factor R f=434 for weakly contaminated soil (<100mg/kg) indicates good ability to reduce As mobility. Highly contaminated soils (>500mg/kg) could not retain any of the added As. Invoked mechanisms affecting As mobility in those soils were adsorption on solid phases such as Fe/Mn-phases and As co-precipitation with Ca. Low As accumulation was found in collected olives (0.3-25μg/kg in flesh and 0.3-5.6μg/kg in pits). However, soil arsenic concentrations are frequently elevated to far above recommended levels and arsenic uptake in faster growing plants has to be assessed. © 2011 Elsevier B.V.

Zoccali C.,CNR Institute of Neuroscience | Zoccali C.,Renal and Transplantation Unit Ospedali Riuniti | Mallamaci F.,CNR Institute of Neuroscience | Mallamaci F.,Renal and Transplantation Unit Ospedali Riuniti
Current Hypertension Reports | Year: 2013

Over the last decade, the biologic interference of uric acid with the cardiovascular (CV) system and the kidney has been intensively investigated, and several experimental studies in animal models and in vitro documented that hyperuricemia may trigger hypertension and incite endothelial dysfunction, vascular damage and renal disease. A substantial proportion of epidemiological studies are compatible with the hypothesis that hyperuricemia may be noxious to the CV system and the kidney as well. However, there are still no well-powered trials testing whether uric acid-lowering interventions may reduce BP or attenuate the risk for adverse CV and renal outcomes. Evidence still remains largely insufficient to recommend changes in the current policy of not prescribing uric acid-lowering drugs to individuals with asymptomatic hyperuricemia. © 2013 Springer Science+Business Media New York.

Battaglia M.,Laval University | Battaglia M.,University of Québec | Ogliari A.,Vita-Salute San Raffaele University | Ogliari A.,San Raffaele Hospital | And 2 more authors.
Neuroscience and Biobehavioral Reviews | Year: 2014

Genetically informative studies showed that genetic and environmental risk factors act and interact to influence liability to (a) panic disorder, (b) its childhood precursor separation anxiety disorder, and (c) heightened sensitivity to CO2, an endophenotype common to both disorders. Childhood adversities including parental loss influence both panic disorder and CO2 hypersensitivity. However, childhood parental loss and separation anxiety disorder are weakly correlated in humans, suggesting the presence of alternative pathways of risk.The transferability of tests that assess CO2 sensitivity - an interspecific quantitative trait common to all mammals - to the animal laboratory setting allowed for environmentally controlled studies of early parental separation. Animal findings paralleled those of human studies, in that different forms of early maternal separation in mice and rats evoked heightened CO2 sensitivity; in mice, this could be explained by gene-by-environment interactional mechanisms.While several questions and issues (including obvious divergences between humans and rodents) remain open, parallel investigations by contemporary molecular genetic tools of (1) human longitudinal cohorts and (2) animals in controlled laboratory settings, can help elucidate the mechanisms beyond these phenomena. © 2014 Elsevier Ltd.

Waghorn G.C.,CNR Institute of Neuroscience
Animal Feed Science and Technology | Year: 2011

Improvements in feed conversion efficiency (FCE) can be applied to individual animals as well as to production from land, as in a farm system. Our focus relates mainly to food production from individual animals within any animal population where there is divergence in the efficiency that individuals use ingested feed for maintenance and production; primarily due to differences in digestion and metabolism. Intake variation from the predicted mean for individuals of a similar size and level of production in a population has been termed residual feed intake (RFI), with low values indicating an efficient animal. Efficient animals require less feed than average and can be expected to produce less CH4 and N2O per unit product than the population average at a similar level of production. Selection for this trait will lower CH4 emissions per animal, unless more animals are kept to eat the feed not required by efficient animals. There are few published evaluations of CH4 yields from animals with divergent RFI and there is little evidence that efficient animals have a different CH4 yield expressed as CH4/kg dry matter (DM) intake. Of equal or greater importance than RFI is the need to select high producing animals, as this will reduce emissions/unit of product, referred to as emissions intensity (Ei). Research should identify productive individuals that have a low RFI to minimise Ei and maintain food production. The extent to which CH4 can be reduced by selection for RFI will depend on the heritability of efficiency, dispersal of efficient animals through all populations and their resilience in a production system (i.e., robustness). The benefit of RFI to lowering greenhouse gas (GHG) emissions is its application, irrespective of farming system (i.e., confined, intensive, extensive grazing), especially because efficient animals are likely to increase farm profitability. Efficient animals are already in all herds and flocks and research must identify and remove inefficient individuals, while retaining and ensuring efficient ones are fit to purpose. However, the biggest benefits to reducing emissions and increasing production will be associated with good animal management practice (e.g., appropriate genetics, reproductive performance, longevity) with efficient animals superimposed. Good animal systems management will improve profitability, and apply to both intensive and extensive systems to increase food production and lower Ei. One dilemma for agriculturists will be the practice of feeding grains to ruminants, as gains in animal efficiency, especially in reduction of Ei, are likely to be biggest with high energy density rations, but feeding grain to ruminants may become an unsustainable practice if food supplies for humans are limited.This paper is part of the special issue entitled: Greenhouse Gases in Animal Agriculture - Finding a Balance between Food and Emissions, Guest Edited by T.A. McAllister, Section Guest Editors: K.A. Beauchemin, X. Hao, S. McGinn and Editor for Animal Feed Science and Technology, P.H. Robinson. © 2011 Elsevier B.V.

Stroppa A.,CNR Institute of Neuroscience | Quarti C.,CNR Institute of Molecular Science and Technologies | De Angelis F.,CNR Institute of Molecular Science and Technologies | Picozzi S.,CNR Institute of Neuroscience
Journal of Physical Chemistry Letters | Year: 2015

Ferroelectricity in halide perovskites currently represents a crucial issue, as it may have an important role for the enhancement of solar cells efficiency. Simulations of ferroelectric properties based on density functional theory are conceptually more demanding compared with conventional inorganic ferroelectrics due to the presence of both organic and inorganic components in the same compound. Here we present a detailed study focused on the prototypical CH3NH3PbI3 perovskite. By using density functional theory combined with symmetry mode analysis, we disentangle the contributions of the methylammonium cations and the role of the inorganic framework, therefore suggesting possible routes to enhance the polarization in this compound. Our estimate of the polarization for the tetragonal phase at low temperature is ∼4.42 μC/cm2, which is substantially lower than that of traditional perovskite oxides. © 2015 American Chemical Society.

D'Ambrosio V.,University of Rome La Sapienza | Herbauts I.,University of Stockholm | Amselem E.,University of Stockholm | Nagali E.,University of Rome La Sapienza | And 5 more authors.
Physical Review X | Year: 2013

The conflict between classical and quantum physics can be identified through a series of yes-no tests on quantum systems, without it being necessary that these systems be in special quantum states. Kochen-Specker (KS) sets of yes-no tests have this property and provide a quantum-versus-classical advantage that is free of the initialization problem that affects some quantum computers. Here, we report the first experimental implementation of a complete KS set that consists of 18 yes-no tests on four-dimensional quantum systems and show how to use the KS set to obtain a state-independent quantum advantage. We first demonstrate the unique power of this KS set for solving a task while avoiding the problem of state initialization. Such a demonstration is done by showing that, for 28 different quantum states encoded in the orbital-angular-momentum and polarization degrees of freedom of single photons, the KS set provides an impossible-to-beat solution. In a second experiment, we generate maximally contextual quantum correlations by performing compatible sequential measurements of the polarization and path of single photons. In this case, state independence is demonstrated for 15 different initial states. Maximum contextuality and state independence follow from the fact that the sequences of measurements project any initial quantum state onto one of the KS set's eigenstates. Our results show that KS sets can be used for quantum-information processing and quantum computation and pave the way for future developments. © Published by the American Physical Society.

Corni S.,CNR Institute of Neuroscience
Nano Letters | Year: 2013

Photosynthesis is triggered by the absorption of light by light-harvesting (LH) pigment-protein complexes followed by excitation energy transfer to the reaction center(s). A promising strategy to achieve control on and to improve light harvesting is to complement the LH complexes with plasmonic particles. Here a recently developed QM/MM/continuum approach is used to investigate the LH process of the peridinin-chlorophyll-protein (PCP) complex on a silver island film. The simulations not only reproduce and interpret the experiments but they also suggest general rules to design novel biohybrid devices; hot-spot configurations in which the LH complex is sandwiched between couples of metal aggregates are found to produce the largest amplifications. Indications about the best distances and orientations are also reported together with illumination and emission geometries of the PCP-NP system necessary to achieve the maximum enhancement. © 2013 American Chemical Society.

Krauss I.R.,University of Naples Federico II | Pica A.,University of Naples Federico II | Merlino A.,University of Naples Federico II | Merlino A.,CNR Institute of Neuroscience | And 5 more authors.
Acta Crystallographica Section D: Biological Crystallography | Year: 2013

Potent second-generation thrombin aptamers adopt a duplex-quadruplex bimodular folding and recognize thrombin exosite II with very high affinity and specificity. A sound model of these oligonucleotides, either free or in complex with thrombin, is not yet available. Here, a structural study of one of these aptamers, HD22-27mer, is presented. The crystal structure of this aptamer in complex with thrombin displays a novel architecture in which the helical stem is enchained to a pseudo-G-quadruplex. The results also underline the role of the residues that join the duplex and quadruplex motifs and control their recruitment in thrombin binding. © 2013 International Union of Crystallography.

Caruso F.,QSTAR | Caruso F.,University of Florence | Caruso F.,University of Ulm | Giovannetti V.,CNR Institute of Neuroscience | And 3 more authors.
Reviews of Modern Physics | Year: 2014

Any physical process can be represented as a quantum channel mapping an initial state to a final state. Hence it can be characterized from the point of view of communication theory, i.e., in terms of its ability to transfer information. Quantum information provides a theoretical framework and the proper mathematical tools to accomplish this. In this context the notion of codes and communication capacities have been introduced by generalizing them from the classical Shannon theory of information transmission and error correction. The underlying assumption of this approach is to consider the channel not as acting on a single system, but on sequences of systems, which, when properly initialized allow one to overcome the noisy effects induced by the physical process under consideration. While most of the work produced so far has been focused on the case in which a given channel transformation acts identically and independently on the various elements of the sequence (memoryless configuration in jargon), correlated error models appear to be a more realistic way to approach the problem. A slightly different, yet conceptually related, notion of correlated errors applies to a single quantum system which evolves continuously in time under the influence of an external disturbance which acts on it in a non-Markovian fashion. This leads to the study of memory effects in quantum channels: a fertile ground where interesting novel phenomena emerge at the intersection of quantum information theory and other branches of physics. A survey is taken of the field of quantum channels theory while also embracing these specific and complex settings. © 2014 American Physical Society.

Agency: GTR | Branch: EPSRC | Program: | Phase: Research Grant | Award Amount: 3.72M | Year: 2014

The conditions in which materials are required to operate are becoming ever more challenging. Operating temperatures and pressures are increasing in all areas of manufacture, energy generation, transport and environmental clean-up. Often the high temperatures are combined with severe chemical environments and exposure to high energy and, in the nuclear industry, to ionising radiation. The production and processing of next-generation materials capable of operating in these conditions will be non-trivial, especially at the scale required in many of these applications. In some cases, totally new compositions, processing and joining strategies will have to be developed. The need for long-term reliability in many components means that defects introduced during processing will need to be kept to an absolute minimum or defect-tolerant systems developed, e.g. via fibre reinforcement. Modelling techniques that link different length and time scales to define the materials chemistry, microstructure and processing strategy are key to speeding up the development of these next-generation materials. Further, they will not function in isolation but as part of a system. It is the behaviour of the latter that is crucial, so that interactions between different materials, the joining processes, the behaviour of the different parts under extreme conditions and how they can be made to work together, must be understood. Our vision is to develop the required understanding of how the processing, microstructures and properties of materials systems operating in extreme environments interact to the point where materials with the required performance can be designed and then manufactured. Aligned with the Materials Genome Initiative in the USA, we will integrate hierarchical and predictive modelling capability in fields where experiments are extremely difficult and expensive. The team have significant experience of working in this area. Composites based on exotic materials such as zirconium diborides and silicon carbide have been developed for use as leading edges for hypersonic vehicles over a 3 year, DSTL funded collaboration between the 3 universities associated with this proposal. World-leading achievements include densifying them in <10 mins using a relatively new technique known as spark plasma sintering (SPS); measuring their thermal and mechanical properties at up to 2000oC; assessing their oxidation performance at extremely high heat fluxes and producing fibre-reinforced systems that can withstand exceptionally high heating rates, e.g. 1000oC s-1, and temperatures of nearly 3000oC for several minutes. The research planned for this Programme Grant is designed to both spin off this knowledge into materials processing for nuclear fusion and fission, aerospace and other applications where radiation, oxidation and erosion resistance at very high temperatures are essential and to gain a deep understanding of the processing-microstructure-property relations of these materials and how they interact with each other by undertaking one of the most thorough assessments ever, allowing new and revolutionary compositions, microstructures and composite systems to be designed, manufactured and tested. A wide range of potential crystal chemistries will be considered to enable identification of operational mechanisms across a range of materials systems and to achieve paradigm changing developments. The Programme Grant would enable us to put in place the expertise required to produce a chain of knowledge from prediction and synthesis through to processing, characterisation and application that will enable the UK to be world leading in materials for harsh environments.

Ast Engineering S.r.l. and CNR Institute of Neuroscience | Date: 2013-04-17

The invention relates to a so-called zero emission AST-CNR/ITM system modular plant for removal of pollutants from flue gases produced by industrial processes. The plant comprises prefabricated modular elements with programmed and automatic operation, easy to mount and assemble on site without undergoing expensive plant stoppage. Each module or reaction tower comprises a plurality of sections vertically arranged on top of one another, which carry out the following functions:- Removal of particulate matter with treatment and removal of chemical pollutants, such as heavy metals, chlorides, fluorides- Treatment and removal of SOx- Treatment and removal of NOx- Capture of CO_(2)- Production of hydrogen- Production of methanol The various sections may be combined according to the requirements of the plant and of the flue gases to be treated.

Rinnan R.,Copenhagen University | Steinke M.,University of Essex | Mcgenity T.,University of Essex | Loreto F.,CNR Institute of Neuroscience
Plant, Cell and Environment | Year: 2014

This review summarizes the current understanding on plant and algal volatile organic compound (VOC) production and emission in extreme environments, where temperature, water availability, salinity or other environmental factors pose stress on vegetation. Here, the extreme environments include terrestrial systems, such as arctic tundra, deserts, CO2 springs and wetlands, and marine systems such as sea ice, tidal rock pools and hypersaline environments, with mangroves and salt marshes at the land-sea interface. The emission potentials at fixed temperature and light level or actual emission rates for phototrophs in extreme environments are frequently higher than for organisms from less stressful environments. For example, plants from the arctic tundra appear to have higher emission potentials for isoprenoids than temperate species, and hypersaline marine habitats contribute to global dimethyl sulphide (DMS) emissions in significant amounts. DMS emissions are more widespread than previously considered, for example, in salt marshes and some desert plants. The reason for widespread VOC, especially isoprenoid, emissions from different extreme environments deserves further attention, as these compounds may have important roles in stress resistance and adaptation to extremes. Climate warming is likely to significantly increase VOC emissions from extreme environments both by direct effects on VOC production and volatility, and indirectly by altering the composition of the vegetation. © 2014 John Wiley & Sons Ltd.

Pagliaroli A.,CNR Institute of Environmental Geology and Geoengineering | Lanzo G.,University of Rome La Sapienza | Tommasi P.,CNR Institute of Environmental Geology and Geoengineering | Di Fiore V.,CNR Institute of Neuroscience
Bulletin of Earthquake Engineering | Year: 2014

The paper presents the results of in-situ and laboratory tests aimed at defining the cyclic properties of soils and soft rocks of the Central Archeological Area of Rome in the framework of the seismic microzonation study of the area. The small-strain shear modulus G0 (or analogously shear wave velocity VS) and the curves expressing shear modulus G and damping ratio D variation with shear strain amplitude were investigated. A large amount of in-hole tests integrated with active surface wave tests were utilized to characterize the small-strain stiffness of the lithotypes identified in the area. Small-strain stiffness values determined by geophysical tests were further compared with those measured in the laboratory showing different behaviors of soils and soft rocks. The effects of sample disturbance and degree of jointing, for soils and soft rocks, respectively, was invoked to explain the observed differences. The shear modulus and damping ratio versus shear strain amplitude curves were determined by means of resonant column and cyclic shear tests, both simple and torsional. The experimental results were compared with literature data on similar soils highlighting some peculiar behaviors. In particular the role of fine matrix in sandy soils and organic matter content of clays on the cyclic properties was stressed. The results showed that an increase in fine matrix and organic content results in a stronger linearity and lower damping ratio. © 2013 Springer Science+Business Media Dordrecht.

Sciascia R.,Polytechnic University of Turin | Sciascia R.,CNR Institute of Neuroscience | Sciascia R.,Massachusetts Institute of Technology | Straneo F.,Woods Hole Oceanographic Institution | And 2 more authors.
Journal of Geophysical Research: Oceans | Year: 2013

The circulation in a glacial fjord driven by a large tidewater glacier is investigated using a nonhydrostatic ocean general circulation model with a melt rate parameterization at the vertical glacier front. The model configuration and water properties are based on data collected in Sermilik Fjord near Helheim Glacier, a major Greenland outlet glacier. The approximately two-layer stratification of the fjord's ambient waters causes the meltwater plume at the glacier front to drive a "double cell" circulation with two distinct outflows, one at the free surface and one at the layers' interface. In summer, the discharge of surface runoff at the base of the glacier (subglacial discharge) causes the circulation to be much more vigorous and associated with a larger melt rate than in winter. The simulated "double cell" circulation is consistent, in both seasons, with observations from Sermilik Fjord. Seasonal differences are also present in the vertical structure of the melt rate, which is maximum at the base of the glacier in summer and at the layers' interface in winter. Simulated submarine melt rates are strongly sensitive to the amount of subglacial discharge, to changes in water temperature, and to the height of the layers. They are also consistent with those inferred from simplified one-dimensional models based on the theory of buoyant plumes. Our results also indicate that to correctly represent the dynamics of the meltwater plume, care must be taken in the choice of viscosity and diffusivity values in the model. ©2013. American Geophysical Union. All Rights Reserved.

Calzolari A.,CNR Institute of Materials | Calzolari A.,CNR Institute of Neuroscience | Ruini A.,CNR Institute of Neuroscience | Ruini A.,University of Modena and Reggio Emilia | Catellani A.,CNR Institute of Neuroscience
Journal of the American Chemical Society | Year: 2011

Molecular sensitization of the single-crystal ZnO (101̄0) surface through absorption of the catechol chromophore is investigated by means of density functional approaches. The resulting type II staggered interface is recovered in agreement with experiments, and its origin is traced back to the presence of molecular-related states in the gap of metal-oxide electronic structure. A systematic analysis carried out for further catecholate adsorbates allows us to identify the basic mechanisms that dictate the energy position of the gap states. The peculiar level alignment is demonstrated to be originated from the simultaneous interplay among the specific anchoring group, the backbone conjugation, and the lateral functional groups. The picture derived from our results provides efficient strategies for tuning the lineup between molecular and oxide states in hybrid interfaces with potential impact for ZnO-based optoelectronic applications. © 2011 American Chemical Society.

Smith M.T.,Pharmacy Development | Moore B.J.,CNR Institute of Neuroscience
Expert Opinion on Pharmacotherapy | Year: 2012

Introduction: Fibromyalgia (FM) is the most common cause of chronic widespread body pain in humans. Co-morbidities include sleep disturbance, fatigue, impaired physical functioning, altered mood and negative effects on health-related quality of life. Pregabalin inhibits presynaptic release of pronociceptive neurotransmitters in the CNS; this likely underpins its therapeutic benefit in patients with FM. Areas covered: This review addresses pregabalin pharmacokinetics, efficacy and adverse event (AE) profiles from randomized controlled trials and open-label extension studies in patients with FM. These effects are compared with those of the serotonin norepinephrine reuptake inhibitors, duloxetine and milnacipran that also have FDA approval for the treatment of fibromyalgia. Expert opinion: At the approved dosages, oral pregabalin has at most a moderate therapeutic benefit above placebo with tolerable side-effects, in no more than 50% of patients with FM. Durability of clinically meaningful (≥ 30%) pain relief in pregabalin-responders has been demonstrated for at least 6-months, but longer-term studies are required as most patients have symptoms for decades. Exclusion of patients with common co-morbidities from the pregabalin RCTs in FM raises questions on the generalizability of the RCT findings to the typical patient seen in clinical practice and so additional investigation is required. © 2012 Informa UK, Ltd.

Szymanska M.H.,University of Warwick | Marchetti F.M.,Autonomous University of Madrid | Sanvitto D.,Autonomous University of Madrid | Sanvitto D.,CNR Institute of Neuroscience
Physical Review Letters | Year: 2010

We study the properties of propagating polariton wave packets and their connection to the stability of doubly charged vortices. Wave-packet propagation and related photoluminescence spectra exhibit a rich behavior dependent on the excitation regime. We show that, because of the nonquadratic polariton dispersion, doubly charged vortices are stable only when initiated in wave packets propagating at small velocities. Vortices propagating at larger velocities, or those imprinted directly into the polariton optical parametric oscillator signal and idler, are unstable to splitting. © 2010 The American Physical Society.

Stroppa A.,CNR Institute of Neuroscience | Barone P.,CNR Institute of Neuroscience | Jain P.,Los Alamos National Laboratory | Perez-Mato J.M.,University of the Basque Country | Picozzi S.,CNR Institute of Neuroscience
Advanced Materials | Year: 2013

On the basis of first-principles calculations, we design a novel Cr-based metal-organic framework to be both multiferroic and magnetoelectric. The compound shows a "double-hybrid" nature: it is a hybrid organic-inorganic compound and it shows hybrid improper ferroelectricity. Here, the coupling of non-polar distortions, such as Jahn-Teller pseudo-rotations and tilting, pave the way to a polar behavior, with the coupling being realized through hydrogen bonds. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Stroppa A.,CNR Institute of Neuroscience | Jain P.,Florida State University | Barone P.,CNR Institute of Neuroscience | Marsman M.,University of Vienna | And 4 more authors.
Angewandte Chemie - International Edition | Year: 2011

Forget me not: In a new multiferroic metal-organic framework (see structure, Cu green, O red, C black, N blue, H gray; arrows show spin configuration), Jahn-Teller and antiferro-distortions induce a switchable ferroelectric polarization, which is coupled to a weak ferromagnetic component. This true magnetoelectric multiferroic should be very attractive for advanced memory devices. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Della Corte F.G.,University of Reggio Calabria | Rao S.,University of Reggio Calabria | Coppola G.,CNR Institute of Neuroscience | Summonte C.,CNR Institute of Neuroscience
Optics Express | Year: 2011

Hydrogenated amorphous silicon (a-Si:H) has been already considered for the objective of passive optical elements, like waveguides and ring resonators, within photonic integrated circuits at λ = 1.55 μm. However the study of its electro-optical properties is still at an early stage, therefore this semiconductor in practice is not considered for light modulation as yet. We demonstrated, for the first time, effective electrooptical modulation in a reverse biased a-Si:H p-i-n waveguiding structure. In particular, phase modulation was studied in a waveguide integrated Fabry-Perot resonator in which the Vπ·Lπ product was determined to be 63 V·cm. Characteristic switch-on and switch-off times of 14 ns were measured. The device employed a wider gap amorphous silicon carbide (a-SiC:H) film for the lower cladding layer instead of silicon oxide. In this way the highest temperature involved in the fabrication process was 170°C, which ensured the desired technological compatibility with CMOS processes. © 2011 Optical Society of America.

Carere M.,Instituto Superiore Of Sanita | Dulio V.,INERIS | Hanke G.,European Commission - Joint Research Center Ispra | Polesello S.,CNR Institute of Neuroscience
TrAC - Trends in Analytical Chemistry | Year: 2012

The Environmental Quality Standards Directive 2008/105/EC (EQSD) marks an important step in the use of sediments and biota as matrices for chemical-status assessment under the Water Framework Directive 2000/60/EC (WFD). Analysis of contaminants in sediments and biota is indeed widely recognized as a cost-effective approach in water-quality monitoring to describe the general contamination level, to supply reference values for local and regional monitoring and to identify areas of concern where additional monitoring effort is needed. Because of the explicit reference in the EQSD to the use of sediments and biota as preferred matrices for the monitoring of substances with accumulation potential - especially for the assessment of long-term trends, but also for compliance checking, wherever appropriate - Member States of the European Union (EU) asked the European Commission to publish a guidance document to enhance the degree of harmonization among EU countries in chemical monitoring of sediments and biota, taking into account best available techniques, standard procedures and common practices. This article presents the key features of that guidance document, its main recommendations for chemical monitoring of sediments and biota and the scope for further improvement in current monitoring practices. © 2012 Elsevier Ltd.

Piraud M.,University Paris - Sud | Pezze L.,University Paris - Sud | Pezze L.,CNR Institute of Neuroscience | Sanchez-Palencia L.,University Paris - Sud
New Journal of Physics | Year: 2013

The macroscopic transport properties in a disordered potential, namely diffusion and weak/strong localization, closely depend on the microscopic and statistical properties of the disorder itself. This dependence is rich in counter-intuitive consequences. It can be particularly exploited in matter wave experiments, where the disordered potential can be tailored and controlled, and anisotropies are naturally present. In this work, we apply a perturbative microscopic transport theory and the self-consistent theory of Anderson localization to study the transport properties of ultracold atoms in anisotropic two-dimensional (2D) and three-dimensional (3D) speckle potentials. In particular, we discuss the anisotropy of single-scattering, diffusion and localization. We also calculate disorder-induced shift of the energy states and propose a method to include it, which amounts to renormalizing energies in the standard on-shell approximation. We show that the renormalization of energies strongly affects the prediction for the 3D localization threshold (mobility edge). We illustrate the theoretical findings with examples which are relevant for current matter wave experiments, where the disorder is created with laser speckle. This paper provides a guideline for future experiments aiming at the precise location of the 3D mobility edge and study of anisotropic diffusion and localization effects in 2D and 3D. © IOP Publishing and Deutsche Physikalische Gesellschaft.

Vicarelli L.,CNR Institute of Neuroscience | Vitiello M.S.,CNR Institute of Neuroscience | Coquillat D.,CNRS Charles Coulomb Laboratory | Lombardo A.,University of Cambridge | And 5 more authors.
Nature Materials | Year: 2012

The unique optoelectronic properties of graphene make it an ideal platform for a variety of photonic applications, including fast photodetectors, transparent electrodes in displays and photovoltaic modules, optical modulators, plasmonic devices, microcavities, and ultra-fast lasers. Owing to its high carrier mobility, gapless spectrum and frequency-independent absorption, graphene is a very promising material for the development of detectors and modulators operating in the terahertz region of the electromagnetic spectrum (wavelengths in the hundreds of micrometres), still severely lacking in terms of solid-state devices. Here we demonstrate terahertz detectors based on antenna-coupled graphene field-effect transistors. These exploit the nonlinear response to the oscillating radiation field at the gate electrode, with contributions of thermoelectric and photoconductive origin. We demonstrate room temperature operation at 0.3 THz, showing that our devices can already be used in realistic settings, enabling large-area, fast imaging of macroscopic samples. © 2012 Macmillan Publishers Limited. All rights reserved.

d'Onofrio A.,Italian National Cancer Institute | Gandolfi A.,CNR Institute of Neuroscience
Journal of Theoretical Biology | Year: 2010

In this work we propose to model chemotherapy taking into account the mutual interaction between tumour growth and the development of tumour vasculature. By adopting a simple model for this interaction, and assuming that the efficacy of a drug can be modulated by the vessel density, we study the constant continuous therapy, the periodic bolus-based therapy, and combined therapy in which a chemotherapic drug is associated with an anti-angiogenic agent. The model allows to represent the vessel-disrupting activity of some standard chemotherapic drugs, and shows, in the case of constant continuous drug administration, the possibility of multiple stable equilibria. The multistability suggests an explanation for some sudden losses of control observed during therapy, and for the beneficial effect of vascular "pruning" exerted by anti-angiogenic agents in combined therapy. Moreover, in case of periodic therapies in which the drug amount administered per unit time is constant ("metronomic" delivery), the model predicts a response, as a function of the bolus frequency, significantly influenced by the extent of the anti-angiogenic activity of the chemotherapic drug and by the dependence of the drug efficacy on the vessel density. © 2010 Elsevier Ltd.

Siepi F.,Instituto Nazionale Tumori Regina Elena | Gatti V.,Instituto Nazionale Tumori Regina Elena | Camerini S.,Instituto Superiore Of Sanita | Crescenzi M.,CNR Institute of Neuroscience | Soddu S.,Instituto Nazionale Tumori Regina Elena
Biochimica et Biophysica Acta - Molecular Cell Research | Year: 2013

HIPK2 (homeodomain-interacting protein kinase-2) binds to and phosphorylates, at Ser and Thr residues, a large number of targets involved in cell division and cell fate decision in response to different physiological or stress stimuli. Inactivation of HIPK2 has been observed in human and mouse cancers supporting its role as a tumor suppressor. Despite the biological relevance of this kinase, very little is known on how HIPK2 becomes catalytically active. Based on sequence homologies, HIPK2 has been taxonomically classified as a subfamily member of the dual-specificity tyrosine-regulated kinases (DYRKs) and the activation-loop Y354 of HIPK2 has been found phosphorylated in different cells; however, the relevance of this Y phosphorylation is presently unknown. Here, we show that HIPK2, which is extensively phosphorylated at S/T sites throughout its functional domains, becomes catalytically active by autophosphorylation at the activation-loop Y354. In particular, we found that, in analogy to DYRKs, HIPK2-Y354 phosphorylation is an autocatalytic event and its prevention, through Y354 substitution with non-phosphorylatable amino acids or by using the kinase inhibitor purvalanol A, induces a strong reduction of the HIPK2 S/T-kinase activity on different substrates. Interestingly, at variance from DYRKs, inhibition of HIPK2-Y354 phosphorylation induces a strong out-of-target Y-kinase activity in cis and a strong cytoplasmic relocalization of the kinase. Together, these results demonstrate that the catalytic activity, substrate specificity, and subcellular localization of HIPK2 are regulated by autophosphorylation of its activation-loop Y354. © 2013 Elsevier B.V.

Cerami M.,IIIA | Straccia U.,CNR Institute of Neuroscience
Information Sciences | Year: 2013

Recently there have been some unexpected results concerning Fuzzy Description Logics (FDLs) with General Concept Inclusions (GCIs). They show that, unlike the classical case, the DL ALC with GCIs does not have the finite model property under Łukasiewicz Logic or Product Logic, the proposed reasoning algorithms are neither correct nor complete and, specifically, knowledge base satisfiability is an undecidable problem for Product Logic. In this work, we show that knowledge base satisfiability is also an undecidable problem for Łukasiewicz Logic. We additionally provide a decision algorithm for acyclic ALC knowledge bases under Łukasiewicz Logic via a Mixed Integer Linear Programming (MILP) based procedure (note, however, that the decidability of this problem is already known). While similar MILP based algorithms have been proposed in the literature for acyclic ALC knowledge bases under Łukasiewicz Logic, none of them exhibit formal proofs of their correctness and completeness, which is the additional contribution here. © 2012 Elsevier Inc. All rights reserved.

Coccia F.,University of Chieti Pescara | Tonucci L.,University of Chieti Pescara | Bosco D.,CNR Institute of Neuroscience | Bressan M.,University of Chieti Pescara | D'Alessandro N.,University of Chieti Pescara
Green Chemistry | Year: 2012

A one-pot green method to synthesise Pt and Pd nanoparticles is reported. Two natural aromatic polymers, lignin and fulvic acid, were used as both reducing and stabilising agents at moderate temperature (80 °C) in water and under aerobic conditions. Full characterisation was performed using TEM, UV-vis, XRD, 195Pt and 1H NMR, FT-IR and GC-MS techniques. In the TEM images, we observed spherical nanoparticles of diameters in the range of 16 nm to 20 nm, in the case of Pd, and smaller ones of not so well defined shapes for Pt. GC-MS of the organic fractions formed during the preparation of the nanoparticles showed defined amounts of vanillin, a well known degradation product of these polymers. This finding indicates that the active participation of lignins and fulvic acids in the metal reduction step. The catalytic activity of the nanoparticles was tested for the NaBH 4 reduction of 4-nitrophenol and for the aerobic oxidation of alcohols, reactions that are always conducted under green conditions. Both Pt and Pd nanoparticles show good catalytic activity in the reduction reaction, while in the aerobic oxidation reaction only the Pt nanoparticles were effective. © 2012 The Royal Society of Chemistry.

Wright L.B.,University of Warwick | Rodger P.M.,University of Warwick | Walsh T.R.,Deakin University | Corni S.,CNR Institute of Neuroscience
Journal of Physical Chemistry C | Year: 2013

Noncovalent recognition between peptides and inorganic materials is an established phenomenon. Key to exploiting these interactions in a wide range of materials self-assembly applications would be to harness the facet-selective control of peptide binding onto these materials. Fundamental understanding of what drives facet-selectivity in peptide binding is developing, but as yet is not sufficient to enable design of predictable facet-specific sequences. Computational simulation of the aqueous peptide-gold interface, commonly used to understand the mechanisms driving adsorption at an atomic level, has thus far neglected the role that surface reconstruction might play in facet specificity. Here the polarizable GolP-CHARMM suite of force fields is extended to include the reconstructed Au(100) surface. The force field, compatible with the bio-organic force field CHARMM, is parametrized using first-principles data. Our extended force field is tailored to reproduce the heterogeneity of weak chemisorbing N and S species to specific locations in the Au(100)(5 × 1) surface identified from the first-principles calculations. We apply our new model to predict and compare the three-dimensional structure of liquid water at Au(111), Au(100)(1 × 1), and Au(100)(5 × 1) interfaces. Using molecular dynamics simulations, we predict an increased likelihood for water-mediated peptide adsorption at the aqueous-Au(100)(1 × 1) interface compared with the Au(100)(5 × 1) interface. Therefore, our findings suggest that peptide binding can discriminate between the native and reconstructed Au(100) interfaces and that the role of reconstruction on binding at the Au(100) interface should not be neglected. © 2013 American Chemical Society.

Hao X.F.,University of Vienna | Stroppa A.,CNR Institute of Neuroscience | Picozzi S.,CNR Institute of Neuroscience | Filippetti A.,CNR Institute of Materials | Franchini C.,University of Vienna
Physical Review B - Condensed Matter and Materials Physics | Year: 2012

We present a study based on several advanced first-principles methods of the recently synthesized PbNiO 3, a rhombohedral antiferromagnetic insulator, which crystallizes in the highly distorted R3c crystal structure. We find this compound electrically polarized with a very large electric polarization of ∼100μC/cm2, thus, even exceeding the polarization of well-known BiFeO 3. PbNiO 3 is a proper ferroelectric with polarization driven by large Pb-O polar displacements along the [111] direction. Contrary to naive expectations, a definite ionic charge of 4+ for the Pb ion cannot be assigned, and, in fact, the large Pb 6s-O2p hybridization drives the ferroelectric distortion through a lone-pair mechanism similar to that of other Pb- and Bi-based multiferroics. © 2012 American Physical Society.

Memmolo P.,Italian Institute of Technology | Memmolo P.,CNR Institute of Neuroscience | Paturzo M.,CNR Institute of Neuroscience | Javidi B.,University of Connecticut | And 2 more authors.
Optics Letters | Year: 2014

Several automatic approaches have been proposed in the past to compute the refocus distance in digital holography (DH). However most of them are based on a maximization or minimization of a suitable amplitude image contrast measure, regarded as a function of the reconstruction distance parameter. Here we show that, by using the sparsity measure coefficient regarded as a refocusing criterion in the holographic reconstruction, it is possible to recover the focus plane and, at the same time, establish the degree of sparsity of digital holograms, when samples of the diffraction Fresnel propagation integral are used as a sparse signal representation. We employ a sparsity measurement coefficient known as Gini's index thus showing for the first time, to the best of our knowledge, its application in DH, as an effective refocusing criterion. Demonstration is provided for different holographic configurations (i.e., lens and lensless apparatus) and for completely different objects (i.e., a thin pure phase microscopic object as an in vitro cell, and macroscopic puppets) preparation. © 2014 Optical Society of America.

Calegari F.,CNR Institute of Neuroscience | Ayuso D.,Autonomous University of Madrid | Trabattoni A.,Polytechnic of Milan | Belshaw L.,Queen's University of Belfast | And 11 more authors.
Science | Year: 2014

In the past decade, attosecond technology has opened up the investigation of ultrafast electronic processes in atoms, simple molecules, and solids. Here, we report the application of isolated attosecond pulses to prompt ionization of the amino acid phenylalanine and the subsequent detection of ultrafast dynamics on a sub-4.5-femtosecond temporal scale, which is shorter than the vibrational response of the molecule. The ability to initiate and observe such electronic dynamics in polyatomic molecules represents a crucial step forward in attosecond science, which is progressively moving toward the investigation of more and more complex systems.

Mingrone G.,Catholic University of the Sacred Heart | Mingrone G.,King's College London | Panunzi S.,CNR Institute of Neuroscience | De Gaetano A.,CNR Institute of Neuroscience | And 7 more authors.
The Lancet | Year: 2015

Background: Randomised controlled trials have shown that bariatric surgery is more effective than conventional treatment for the short-term control of type-2 diabetes. However, published studies are characterised by a relatively short follow-up. We aimed to assess 5 year outcomes from our randomised trial designed to compare surgery with conventional medical treatment for the treatment of type 2 diabetes in obese patients. Methods: We did our open-label, randomised controlled trial at one diabetes centre in Italy. Patients aged 30-60 years with a body-mass index of 35 kg/m2 or more and a history of type 2 diabetes lasting at least 5 years were randomly assigned (1:1:1), via a computer-generated randomisation procedure, to receive either medical treatment or surgery by Roux-en-Y gastric bypass or biliopancreatic diversion. Participants were aware of treatment allocation before the operation and study investigators were aware from the point of randomisation. The primary endpoint was the rate of diabetes remission at 2 years, defined as a glycated haemaglobin A1c (HbA1c) concentration of 6·5% or less (≤47·5 mmol/mol) and a fasting glucose concentration of 5·6 mmol/L or less without active pharmacological treatment for 1 year. Here we analyse glycaemic and metabolic control, cardiovascular risk, medication use, quality of life, and long-term complications 5 years after randomisation. Analysis was by intention to treat for the primary endpoint and by per protocol for the 5 year follow-up. This study is registered with ClinicalTrials.gov, number NCT00888836. Findings: Between April 27, 2009, and Oct 31, 2009, we randomly assigned 60 patients to receive either medical treatment (n=20) or surgery by gastric bypass (n=20) or biliopancreatic diversion (n=20); 53 (88%) patients completed 5 years' follow-up. Overall, 19 (50%) of the 38 surgical patients (seven [37%] of 19 in the gastric bypass group and 12 [63%] of 19 in the bilipancreatic diversion group) maintained diabetes remission at 5 years, compared with none of the 15 medically treated patients (p=0·0007). We recorded relapse of hyperglycaemia in eight (53%) of the 15 patients who achieved 2 year remission in the gastric bypass group and seven (37%) of the 19 patients who achieved 2 year remission in the biliopancreatic diversion group. Eight (42%) patients who underwent gastric bypass and 13 (68%) patients who underwent biliopancreatic diversion had an HbA1c concentration of 6·5% or less (≤47·5 mmol/mol) with or without medication, compared with four (27%) medically treated patients (p=0·0457). Surgical patients lost more weight than medically treated patients, but weight changes did not predict diabetes remission or relapse after surgery. Both surgical procedures were associated with significantly lower plasma lipids, cardiovascular risk, and medication use. Five major complications of diabetes (including one fatal myocardial infarction) arose in four (27%) patients in the medical group compared with only one complication in the gastric bypass group and no complications in the biliopancreatic diversion group. No late complications or deaths occurred in the surgery groups. Nutritional side-effects were noted mainly after biliopancreatic diversion. Interpretation: Surgery is more effective than medical treatment for the long-term control of obese patients with type 2 diabetes and should be considered in the treatment algorithm of this disease. However, continued monitoring of glycaemic control is warranted because of potential relapse of hyperglycaemia. © 2015 Elsevier Ltd.

Bason M.G.,CNR Institute of Neuroscience | Viteau M.,CNR Institute of Neuroscience | Malossi N.,University of Pisa | Huillery P.,CNR Institute of Neuroscience | And 9 more authors.
Nature Physics | Year: 2012

Accurately controlling a quantum system is a fundamental requirement in quantum information processing and the coherent manipulation of molecular systems. The ultimate goal in quantum control is to prepare a desired state with the highest fidelity allowed by the available resources and the experimental constraints. Here we experimentally implement two optimal high-fidelity control protocols using a two-level quantum system comprising Bose-Einstein condensates in optical lattices. The first is a short-cut protocol that reaches the maximum quantum-transformation speed compatible with the Heisenberg uncertainty principle. In the opposite limit, we realize the recently proposed transitionless superadiabatic protocols in which the system follows the instantaneous adiabatic ground state nearly perfectly. We demonstrate that superadiabatic protocols are extremely robust against control parameter variations, making them useful for practical applications. © 2012 Macmillan Publishers Limited. All rights reserved.

Straccia U.,CNR Institute of Neuroscience | Madrid N.,University of Malaga
Fuzzy Sets and Systems | Year: 2012

We present a top-k query answering procedure for Fuzzy Logic Programming, in which arbitrary computable functions may appear in the rule bodies to manipulate truth values. The top-k ranking problem, i.e. determining the top k answers to a query, becomes important as soon as the set of facts becomes quite large. © 2012 Elsevier B.V.

Di Paola L.,Biomedical University of Rome | De Ruvo M.,Institute of Systems Analysis and Computer Science IASI | Paci P.,Institute of Systems Analysis and Computer Science IASI | Santoni D.,CNR Institute of Neuroscience | Giuliani A.,Instituto Superiore Of Sanita
Chemical Reviews | Year: 2013

Biological chemistry, additionally, poses intriguing issues regarding the analysis of complex kinetic schemes, made up of several chemical reactions with nonlinear kinetic expression for the corresponding reaction rate. A protein structure is a complex three-dimensional object, formally defined by the coordinates in 3D space of its atoms. Since the first works on the subject in the early 1960s, a large number of protein molecular structures has been resolved, now accessible on devoted web databases. The large availability of protein molecular structures has not solved yet many of the issues regarding the strict relationship between structure and function in the protein universe. The contact density of a protein decreases exponentially with the number of residues; thus, bigger proteins are much less compact than smaller ones, giving rise to bigger cavities and a more fuzzy distinction between internal and external milieu.

Deviatov E.V.,RAS Institute of Solid State Physics | Lorke A.,University of Duisburg - Essen | Biasiol G.,CNR Institute of Materials | Sorba L.,CNR Institute of Neuroscience
Physical Review Letters | Year: 2011

We use the edge of the quantum Hall sample to study the possibility for counterpropagating neutral collective excitations. A novel sample design allows us to independently investigate charge and energy transport along the edge. We experimentally observe an upstream energy transfer with respect to the electron drift for the filling factors 1 and 1/3. Our analysis indicates that a neutral collective mode at the interaction-reconstructed edge is a proper candidate for the experimentally observed effect. © 2011 American Physical Society.

Vitiello M.S.,CNR Institute of Applied Physics Nello Carrara | Vitiello M.S.,CNR Institute of Neuroscience | Coquillat D.,CNRS Charles Coulomb Laboratory | Viti L.,CNR Institute of Neuroscience | And 7 more authors.
Nano Letters | Year: 2012

The growth of semiconductor nanowires (NWs) has recently opened new paths to silicon integration of device families such as light-emitting diodes, high-efficiency photovoltaics, or high-responsivity photodetectors. It is also offering a wealth of new approaches for the development of a future generation of nanoelectronic devices. Here we demonstrate that semiconductor nanowires can also be used as building blocks for the realization of high-sensitivity terahertz detectors based on a 1D field-effect transistor configuration. In order to take advantage of the low effective mass and high mobilities achievable in III-V compounds, we have used InAs nanowires, grown by vapor-phase epitaxy, and properly doped with selenium to control the charge density and to optimize source-drain and contact resistance. The detection mechanism exploits the nonlinearity of the transfer characteristics: the terahertz radiation field is fed at the gate-source electrodes with wide band antennas, and the rectified signal is then read at the output in the form of a DC drain voltage. Significant responsivity values (>1 V/W) at 0.3 THz have been obtained with noise equivalent powers (NEP) < 2 ×10 -9 W/(Hz) 1/2 at room temperature. The large existing margins for technology improvements, the scalability to higher frequencies, and the possibility of realizing multipixel arrays, make these devices highly competitive as a future solution for terahertz detection. © 2011 American Chemical Society.

Vassen W.,VU University Amsterdam | Cohen-Tannoudji C.,Kastler-Brossel Laboratory | Leduc M.,Kastler-Brossel Laboratory | Boiron D.,ParisTech Optics Institute | And 6 more authors.
Reviews of Modern Physics | Year: 2012

Experimental work on cold, trapped metastable noble gases is reviewed. The aspects which distinguish work with these atoms from the large body of work on cold, trapped atoms in general is emphasized. These aspects include detection techniques and collision processes unique to metastable atoms. Several experiments exploiting these unique features in fields including atom optics and statistical physics are described. Precision measurements on these atoms including fine structure splittings, isotope shifts, and atomic lifetimes are also discussed. © 2012 American Physical Society.

Picano E.,CNR Institute of Neuroscience | Vano E.,CNR Institute of Neuroscience | Vano E.,Complutense University of Madrid
Cardiovascular Ultrasound | Year: 2011

The "radiation issue" is the need to consider possible deterministic effects (e.g., skin injuries) and long-term cancer risks due to ionizing radiation in the risk-benefit assessment of diagnostic or therapeutic testing. Although there are currently no data showing that high-dose medical studies have actually increased the incidence of cancer, the "linear-no threshold" model in radioprotection assumes that no safe dose exists; all doses add up in determining cancer risks; and the risk increases linearly with increasing radiation dose. The possibility of deterministic effects should also be considered when skin or lens doses may be over the threshold. Cardiologists have a special mission to avoid unjustified or non-optimized use of radiation, since they are responsible for 45% of the entire cumulative effective dose of 3.0 mSv (similar to the radiological risk of 150 chest x-rays) per head per year to the US population from all medical sources except radiotherapy. In addition, interventional cardiologists have an exposure per head per year two to three times higher than that of radiologists. The most active and experienced interventional cardiologists in high volume cath labs have an annual exposure equivalent to around 5 mSv per head and a professional lifetime attributable to excess cancer risk on the order of magnitude of 1 in 100. Cardiologists are the contemporary radiologists but sometimes imperfectly aware of the radiological dose of the examination they prescribe or practice, which can range from the equivalent of 1-60 mSv around a reference dose average of 10-15 mSv for a percutaneous coronary intervention, a cardiac radiofrequency ablation, a multi-detector coronary angiography, or a myocardial perfusion imaging scintigraphy. A good cardiologist cannot be afraid of life-saving radiation, but must be afraid of radiation unawareness and negligence. © 2011 Picano and Vano; licensee BioMed Central Ltd.

Le Ber I.,CRicm UMRS 975 | Le Ber I.,CNR Institute of Neuroscience
Revue Neurologique | Year: 2013

The last decade marked a turning point in the knowledge of frontotemporal lobar degenerations (FTLD). Major discoveries were made with the identification of TDP-43 and FUS, two novel key players in FTLD. The growing number of FTLD genes has considerably changed our clinical practice. The high intrafamilial variability of phenotypes underlines the necessity of a careful interview concerning the family history, regarding FTLD diseases, but also other neurodegenerative and extra-neurological disorders. Knowledge of the different genetic forms of FTLD and their associated phenotypes become essential to propose appropriate genetic diagnosis to the patients, and deliver accurate genetic counseling to their families. We propose an algorithm based on four criteria to help to pinpoint the genetic cause of FTLD: Presence of ALS in the patient or family; age at onset of FTLD; progranulin plasma level; and other disorders present in the patient or family. Presence of ALS is strongly indicative of a C9ORF72 expansion; a very early age at onset (< 50 years), parkinsonism and oculomotor dysfunction are indicative of MAPT mutations; whereas hallucinations, CBDS and PNFA are indicative of PGRN mutations. A C9ORF72 repeat expansion should be searched for therefore in patients with FTLD-ALS, followed by sequencing of exon 6 of TARDBP gene in negative cases. Since C9ORF72 expansions are as frequent as PGRN mutations in patients with pure FTLD, both should be investigated, except in early familial FTLD (< 50) where MAPT mutations should be searched for first. VCP, SQSTM1 and hnRNPA2B1 gene-sequencing could be proposed in patients or families presenting 'multisystem proteinopathy'. The genes currently identified explain 50-60% of familial forms of FTLD. The identification of new FTLD genes involved remains a major challenge to gain further insight into the pathology and even better clarify the classification of FTLD in the future. © 2013 Elsevier Masson SAS.

Storlazzi A.,University Paris - Sud | Storlazzi A.,CNR Institute of Neuroscience | Gargano S.,CNR Institute of Neuroscience | Ruprich-Robert G.,University Paris - Sud | And 4 more authors.
Cell | Year: 2010

Meiotic chromosome pairing involves not only recognition of homology but also juxtaposition of entire chromosomes in a topologically regular way. Analysis of filamentous fungus Sordaria macrospora reveals that recombination proteins Mer3, Msh4, and Mlh1 play direct roles in all of these aspects, in advance of their known roles in recombination. Absence of Mer3 helicase results in interwoven chromosomes, thereby revealing the existence of features that specifically ensure " entanglement avoidance." Entanglements that remain at zygotene, i.e., " interlockings," require Mlh1 for resolution, likely to eliminate constraining recombinational connections. Patterns of Mer3 and Msh4 foci along aligned chromosomes show that the double-strand breaks mediating homologous alignment have spatially separated ends, one localized to each partner axis, and that pairing involves interference among developing interhomolog interactions. We propose that Mer3, Msh4, and Mlh1 execute all of these roles during pairing by modulating the state of nascent double-strand break/partner DNA contacts within axis-associated recombination complexes. © 2010 Elsevier Inc.

Welte L.,Autonomous University of Madrid | Calzolari A.,CNR Institute of Neuroscience | Di Felice R.,CNR Institute of Neuroscience | Zamora F.,Autonomous University of Madrid | Gomez-Herrero J.,Autonomous University of Madrid
Nature Nanotechnology | Year: 2010

Organic molecules can self-assemble into well-ordered structures, but the conductance of these structures is limited, which is a disadvantage for applications in molecular electronics. Conductivity can be improved by using coordination polymersin which metal centres are incorporated into a molecular backboneand such structures have been used as molecular wires by self-assembling them into ordered films on metal surfaces. Here, we report electrically conductive nanoribbons of the coordination polymer [Pt 2 I(S 2 CCH 3) 4 ] n self-assembled on an insulating substrate by direct sublimation of polymer crystals. Conductance atomic force microscopy is used to probe the electrical characteristics of a few polymer chains (∼10) within the nanoribbons. The observed currents exceed those previously sustained in organic and metal-organic molecules assembled on surfaces by several orders of magnitude and over much longer distances. These results, and the results of theoretical calculations based on density functional theory, confirm coordination polymers as candidate materials for applications in molecular electronics. © 2010 Macmillan Publishers Limited. All rights reserved.

De Caro L.,CNR Institute of Crystallography | Carlino E.,CNR Institute of Materials | Caputo G.,University of Salento | Caputo G.,CNR Institute of Neuroscience | And 3 more authors.
Nature Nanotechnology | Year: 2010

High-resolution imaging of low-atomic-number chemical elements using electron microscopy is challenging and may require the use of high doses of electrons. Electron diffractive imaging, which creates real-space images using diffraction intensities and phase retrieval methods, could overcome such issues, although it is also subject to limitations. Here, we show that a combination of electron diffractive imaging and high-resolution transmission electron microscopy can image individual TiO 2 nanocrystals with a resolution of 70pm while exposing the specimen to a low dose of electrons. Our approach, which does not require spherical and chromatic aberration correction, can reveal the location of light atoms (oxygen) in the crystal lattice. We find that the unit cell in nanoscale TiO 2 is subtly different to that in the corresponding bulk. © 2010 Macmillan Publishers Limited. All rights reserved.

Rao S.,University of Reggio Calabria | Coppola G.,CNR Institute of Neuroscience | Gioffre M.A.,CNR Institute of Neuroscience | Della Corte F.G.,University of Reggio Calabria
Optics Express | Year: 2012

A very simple and fast MachZehnder electro-optic modulator based on a p-i-n configuration, operating at λ = 1.55 μm, has been fabricated at 170°C using the low cost technology of hydrogenated amorphous silicon (a-Si:H). In spite of the device simplicity, refractive index modulation was achieved through the free carrier dispersion effect resulting in characteristic rise and fall times of ∼2.5 ns. By reverse biasing the p-i-n device, the voltage-length product was estimated to be Vπ Lπ = 40 V·cm measurements. Such bandwidth performance in as-deposited a-Si:H demonstrates the potential of this material for the fabrication of fast active photonic devices integrated on standard microelectronic substrates. © 2012 Optical Society of America.

Biasiol G.,CNR Institute of Materials | Heun S.,CNR Institute of Neuroscience
Physics Reports | Year: 2011

In this article we review the extensive experimental work on the compositional mapping of semiconductor quantum dots and rings. After a brief introduction of the various experimental techniques used for this purpose, the body of experimental results is presented, ordered by experimental technique (transmission electron microscopy, X-ray diffraction, photoelectron microscopy, scanning probe microscopy, and ion-atom probes) and material system (mainly III-Vs and Ge/Si). The article concludes with a discussion which critically compares these results and outlines some general trends. © 2010 Elsevier B.V.

Wright L.B.,University of Warwick | Rodger P.M.,University of Warwick | Corni S.,CNR Institute of Neuroscience | Walsh T.R.,Deakin University
Journal of Chemical Theory and Computation | Year: 2013

Computational simulation of peptide adsorption at the aqueous gold interface is key to advancing the development of many applications based on gold nanoparticles, ranging from nanomedical devices to smart biomimetic materials. Here, we present a force field, GolP-CHARMM, designed to capture peptide adsorption at both the aqueous Au(111) and Au(100) interfaces. The force field, compatible with the bio-organic force field CHARMM, is parametrized using a combination of experimental and first-principles data. Like its predecessor, GolP (Iori, F.; et al. J. Comput. Chem.2009, 30, 1465), this force field contains terms to describe the dynamic polarization of gold atoms, chemisorbing species, and the interaction between sp2 hybridized carbon atoms and gold. A systematic study of small molecule adsorption at both surfaces using the vdW-DF functional (Dion, M.; et al. Phys. Rev. Lett.2004, 92, 246401-1. Thonhauser, T.; et al. Phys. Rev. B2007, 76, 125112) is carried out to fit and test force field parameters and also, for the first time, gives unique insights into facet selectivity of gold binding in vacuo. Energetic and spatial trends observed in our DFT calculations are reproduced by the force field under the same conditions. Finally, we use the new force field to calculate adsorption energies, under aqueous conditions, for a representative set of amino acids. These data are found to agree with experimental findings. © 2013 American Chemical Society.

Pezze L.,CNR Institute of Neuroscience | Hyllus P.,University of the Basque Country | Smerzi A.,CNR Institute of Neuroscience
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2015

We provide general bounds of phase estimation sensitivity in linear two-mode interferometers. We consider probe states with a fluctuating total number of particles. With incoherent mixtures of states with different total number of particles, particle entanglement is necessary but not sufficient to overcome the shot noise limit. The highest possible phase estimation sensitivity, the Heisenberg limit, is established under general unbiased properties of the estimator. If coherences can be created, manipulated, and detected, the Heisenberg limit can only be set in the central limit, with a sufficiently large repetition of interferometric measurements. © 2015 American Physical Society.

Cantinotti M.,CNR Institute of Neuroscience | Assanta N.,CNR Institute of Neuroscience | Murzi B.,CNR Institute of Neuroscience | Lopez L.,Childrens Hospital at Montefiore
Heart | Year: 2014

Haemodynamically insignificant left-to-right shunts are frequently discovered when screening for congenital heart disease, resulting in significant economic and psychosocial impact. A literature search was performed within the National Library of Medicine using the keywords small/insignificant/silent atrial septal defect (ASD), ventricular septal defect (VSD), patent ductus arteriosus (PDA) and patent foramen ovale (PFO). The search was refined by adding the keywords definition, classification and follow-up. Our analysis revealed significant heterogeneity in the evaluation and management of innocent left-to-right shunts. The definitions for small defects vary greatly, making it difficult to distinguish between physiologic and pathologic lesions (eg, a PFO vs a true ASD). Most small defects will partially or completely resolve spontaneously early in life. If spontaneous resolution does not occur, the risk for long-term complications (such as embolic events and endocarditis) is low but poses several practical and ethical issues: immediate discharge versus long-term follow-up, duration and frequency of followup, and content and method of discussions with the parents. Additionally, there is controversy pertaining to treatment for PDAs and VSDs, particularly among interventional cardiologists, even though risk/benefit analyses are lacking. Standards and guidelines using consensus opinion for the management of insignificant left-to-right shunts are needed to address the heterogeneity in diagnosis and management as well as use of resources, ethical and psychosocial issues.

Agency: GTR | Branch: EPSRC | Program: | Phase: Fellowship | Award Amount: 1.24M | Year: 2013

The main aim of this project is to explore novel emergent phenomena in far from equilibrium quantum systems across different fields of research: from solid-state light-matter systems such as superconducting circuits, semiconductor micro-structures and quantum spins to ultra-cold atomic gases. Such cross-fertilisation between traditionally distinct areas is an essential ingredient in successful approach to understanding far from equilibrium collective processes together with the development of new efficient theoretical tools. EPSRC Physics Grand Challenge Survey has identified that compared with that of equilibrium states, our understanding of states far from equilibrium is in its infancy and that on the theory front, there are significant gaps in knowledge, especially in quantum theory. At the same time the problem is of considerable scientific and technological importance and with unforeseeable potential for applications. We shall study exotic quantum orders, bistabilities, pattern formation and other collective phenomena in state-of-the art light-matter systems. An important aspect of our project is to focus on systems, or their features, which in the longer run could lead to potential device applications: from polariton lasers and LEDs, low threshold optical switches, optical transistors, logic gates and finally polariton integrated circuits to quantum computers. Our theoretical analysis will be linked directly to the experiments of our project partners worldwide.

Agency: European Commission | Branch: FP7 | Program: MC-ITN | Phase: PEOPLE-2007-1-1-ITN | Award Amount: 4.44M | Year: 2008

This is a multi-disciplinary training programme focussed on the experimental and clinical problems associated with axonal damage and repair in the central nervous system. This is a central feature of a wide variety of disorders of the CNS. Future advances in this area depend on training a cohort of young researches with multiple skills. The programme encompasses ten academic and two commercial organisations. Each student will be trained in a variety of theoretical and technical approaches, based on the complementary expertise of the collaborating partners. In addition, there will be a strong emphasis on the commercial exploitation and development of potential new therapies. The individual projects are strongly cross-disciplinary, and a series of workshops, seminars and online tutorials will ensure the collective resources of each participant being available to each student. These will foster a sense of collegiality amongst the students themselves, and knowledge of the work going on in the labs of the consortium. The programme will have a common organisation strategy, with a balance between control by the coordinators and delegation to individual laboratories. The topics themselves range from studies on the molecular biology of gene expression during axonal damage and regeneration, through cellular approaches for rescuing axons, artificial systems for growing and studying axons in vitro, the use of stem cells as regenerative procedures, advanced imaging techniques for assessing axonal integrity, studies on ways to alter axonal plasticity, pharmacological approaches to preventing or restoring axonal damage, new surgical and experimental methods for studying axonal structure and function, tests of recovery (including both physiological and behavioural techniques) and the contribution of axonal malfunction to animal models of specific diseases. Students will also be taught the avenues available for commercial exploitation of experimental findings.

Madami M.,University of Perugia | Bonetti S.,KTH Royal Institute of Technology | Consolo G.,Messina University | Tacchi S.,University of Perugia | And 8 more authors.
Nature Nanotechnology | Year: 2011

Spin torque oscillators with nanoscale electrical contacts are able to produce coherent spin waves in extended magnetic films, and offer an attractive combination of electrical and magnetic field control, broadband operation, fast spin-wave frequency modulation, and the possibility of synchronizing multiple spin-wave injection sites. However, many potential applications rely on propagating (as opposed to localized) spin waves, and direct evidence for propagation has been lacking. Here, we directly observe a propagating spin wave launched from a spin torque oscillator with a nanoscale electrical contact into an extended Permalloy (nickel iron) film through the spin transfer torque effect. The data, obtained by wave-vector-resolved micro-focused Brillouin light scattering, show that spin waves with tunable frequencies can propagate for several micrometres. Micromagnetic simulations provide the theoretical support to quantitatively reproduce the results. © 2011 Macmillan Publishers Limited. All rights reserved.

Brancolini G.,CNR Institute of Neuroscience | Kokh D.B.,Heidelberg Institute for Theoretical Studies HITS | Calzolai L.,European Commission - Joint Research Center Ispra | Wade R.C.,Heidelberg Institute for Theoretical Studies HITS | And 2 more authors.
ACS Nano | Year: 2012

Protein-nanoparticle associations have important applications in nanoscience and nanotechnology such as targeted drug delivery and theranostics. However, the mechanisms by which proteins recognize nanoparticles and the determinants of specificity are still poorly understood at the microscopic level. Gold is a promising material in nanoparticles for nanobiotechnology applications because of the ease of its functionalization and its tunable optical properties. Ubiquitin is a small, cysteine-free protein (ubiquitous in eukaryotes) whose binding to gold nanoparticles has been characterized recently by nuclear magnetic resonance (NMR). To reveal the molecular basis of these protein-nanoparticle interactions, we performed simulations at multiple levels (ab initio quantum mechanics, classical molecular dynamics and Brownian dynamics) and compared the results with experimental data (circular dichroism and NMR). The results provide a model of the ensemble of structures constituting the ubiquitin-gold surface complex, and insights into the driving forces for the binding of ubiquitin to gold nanoparticles, the role of nanoparticle surfactants (citrate) in the association process, and the origin of the perturbations in the NMR chemical shifts. © 2012 American Chemical Society.

Romeo F.,University of Salerno | Romeo F.,CNR Institute of Neuroscience | Citro R.,University of Salerno | Citro R.,CNR Institute of Neuroscience
Physical Review Letters | Year: 2013

We study a spin valve with a triplet superconductor spacer intercalated between two ferromagnets with noncollinear magnetizations. We show that the magnetoresistance of the triplet spin valve depends on the relative orientations of the d vector, characterizing the superconducting order parameter, and the magnetization directions of the ferromagnetic layers. For devices characterized by a long superconductor, the effects of a polarized current sustained by Cooper pairs only are observed. In this regime, a supermagnetoresistance effect emerges, and the chiral symmetry of the order parameter of the superconducting spacer is easily recognized. Our findings open new perspectives in designing spintronics devices based on the cooperation of ferromagnetic and triplet correlations. © 2013 American Physical Society.

Gualdi G.,University of Salerno | Giampaolo S.M.,University of Salerno | Illuminati F.,CNR Institute of Neuroscience
Physical Review Letters | Year: 2011

We introduce and discuss the concept of modular entanglement. This is the entanglement that is established between the end points of modular systems composed by sets of interacting moduli of arbitrarily fixed size. We show that end-to-end modular entanglement scales in the thermodynamic limit and rapidly saturates with the number of constituent moduli. We clarify the mechanisms underlying the onset of entanglement between distant and noninteracting quantum systems and its optimization for applications to quantum repeaters and entanglement distribution and sharing. © 2011 American Physical Society.

Bertolami O.,University of Porto | March R.,CNR Institute of Neuroscience | March R.,National Institute of Nuclear Physics, Italy | Paramos J.,University of Lisbon
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

We extend the analysis of Chiba et al. of Solar System constraints on f(R) gravity to a class of nonminimally coupled (NMC) theories of gravity. These generalize f(R) theories by replacing the action functional of general relativity with a more general form involving two functions f1(R) and f2(R) of the Ricci scalar curvature R. While the function f1(R) is a nonlinear term in the action, analogous to f(R) gravity, the function f2(R) yields a NMC between the matter Lagrangian density Lm and the scalar curvature. The developed method allows for obtaining constraints on the admissible classes of functions f1(R) and f2(R), by requiring that predictions of NMC gravity are compatible with Solar System tests of gravity. Then we consider a NMC model which accounts for the observed accelerated expansion of the Universe and we show that such a model cannot be constrained by the present method. © 2013 American Physical Society.

Barthlott C.,Karlsruhe Institute of Technology | Davolio S.,CNR Institute of Neuroscience
Quarterly Journal of the Royal Meteorological Society | Year: 2015

This study focuses on the initiation of deep convection during a heavy precipitation episode, which occurred during the first Special Observation Period (SOP 1) of the Hydrological cycle in the Mediterranean Experiment (HyMeX). In the course of 14 and 15 October 2012 (Intensive Observation Period 13), intense convective events affected southern France, Corsica and several regions of Italy. Numerical simulations are performed with two state-of-the-art numerical weather prediction models (COSMO and MOLOCH), driven by the same initial and boundary data and operated on an identical domain. With this set-up, the sensitivity of the model results to horizontal grid spacing and terrain elevation is assessed. Furthermore, model outputs are compared with observations from rain-gauges, radars and radiosondes made during the campaign. Although the higher resolution runs show a higher correlation with observed precipitation, the influence of model grid spacing on total precipitation amount or timing is rather weak. Since the overall performance of both mesoscale models is fairly good, they are used together to investigate the physical processes characterizing IOP 13. In particular, the differences in the location and timing of convection between the simulations are used to identify and explore those processes that need to be well represented in order to reproduce the mechanisms initiating heavy precipitation in the Mediterranean region adequately. © 2015 Royal Meteorological Society.

Candini A.,CNR Institute of Neuroscience | Candini A.,CNRS Neel Institute | Klyatskaya S.,Karlsruhe Institute of Technology | Ruben M.,Karlsruhe Institute of Technology | And 4 more authors.
Nano Letters | Year: 2011

The possibility to graft nano-objects directly on its surface makes graphene particularly appealing for device and sensing applications. Here we report the design and the realization of a novel device made by a graphene nanoconstriction decorated with TbPc2 magnetic molecules (Pc = phthalocyananine), to electrically detect the magnetization reversal of the molecules in proximity with graphene. A magnetoconductivity signal as high as 20% is found for the spin reversal, revealing the uniaxial magnetic anisotropy of the TbPc2 quantum magnets. These results depict the behavior of multiple-field-effect nanotransistors with sensitivity at the single-molecule level. © 2011 American Chemical Society.

Musolino V.,Polytechnic of Milan | Pievatolo A.,CNR Institute of Neuroscience | Tironi E.,Polytechnic of Milan
Energy | Year: 2011

In the context of efficient energy use, electrical energy in electric drives plays a fundamental role. High efficiency energy storage systems permit energy recovery, peak shaving and power quality functions. Due to their cost and the importance of system integration, there is a need for a correct design based on technical-economical optimization. In this paper, a method to design a centralized storage system for the recovery of the power regenerated by a number of electric drives is presented. It is assumed that the drives follow deterministic power cycles, but shifted by an uncertain amount. Therefore the recoverable energy and, consequently, the storage size requires the optimization of a random cost function, embedding both the plant total cost and the saving due to the reduced energy consumption during the useful life of the storage. The underlying stochastic model for the power profile of the drives as a whole is built from a general Markov chain framework. A numerical example, based on Monte Carlo simulations, concerns the maximization of the recoverable potential energy of multiple bridge cranes, supplied by a unique grid connection point and a centralized supercapacitor storage system. © 2011 Elsevier Ltd.

Concina I.,CNR Institute of Neuroscience | Concina I.,University of Brescia | Vomiero A.,CNR Institute of Neuroscience | Vomiero A.,Lulea University of Technology
Small | Year: 2015

This Review provides a brief summary of the most recent research developments in the synthesis and application of nanostructured metal oxide semiconductors for dye sensitized and quantum dot sensitized solar cells. In these devices, the wide bandgap semiconducting oxide acts as the photoanode, which provides the scaffold for light harvesters (either dye molecules or quantum dots) and electron collection. For this reason, proper tailoring of the optical and electronic properties of the photoanode can significantly boost the functionalities of the operating device. Optimization of the functional properties relies with modulation of the shape and structure of the photoanode, as well as on application of different materials (TiO2, ZnO, SnO2) and/or composite systems, which allow fine tuning of electronic band structure. This aspect is critical because it determines exciton and charge dynamics in the photoelectrochemical system and is strictly connected to the photoconversion efficiency of the solar cell. The different strategies for increasing light harvesting and charge collection, inhibiting charge losses due to recombination phenomena, are reviewed thoroughly, highlighting the benefits of proper photoanode preparation, and its crucial role in the development of high efficiency dye sensitized and quantum dot sensitized solar cells. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Di Sante D.,University of L'Aquila | Barone P.,CNR Institute of Neuroscience | Bertacco R.,Polytechnic of Milan | Picozzi S.,CNR Institute of Neuroscience
Advanced Materials | Year: 2013

Relativistic effects, including the Rashba effect, are increasingly seen as key ingredients in spintronics. A link between Rashba physics and the field of ferroelectrics is established by predicting giant Rashba spin-splitting in bulk GeTe (see the Figure showing the band-structure as well as in-plane and out- of-plane spin polarization for a constant energy cut). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Avella A.,University of Salerno | Avella A.,CNR Institute of Neuroscience
Advances in Condensed Matter Physics | Year: 2014

The microscopical analysis of the unconventional and puzzling physics of the underdoped cuprates, as carried out lately by means of the composite operator method (COM) applied to the 2D Hubbard model, is reviewed and systematized. The 2D Hubbard model has been adopted as it has been considered the minimal model capable of describing the most peculiar features of cuprates held responsible for their anomalous behavior. COM is designed to endorse, since its foundation, the systematic emergence in any SCS of new elementary excitations described by composite operators obeying noncanonical algebras. In this case (underdoped cuprates - 2D Hubbard model), the residual interactions - beyond a 2-pole approximation - between the new elementary electronic excitations, dictated by the strong local Coulomb repulsion and well described by the two Hubbard composite operators, have been treated within the noncrossing approximation. Given this recipe and exploiting the few unknowns to enforce the Pauli principle content in the solution, it is possible to qualitatively describe some of the anomalous features of high-Tc cuprate superconductors such as large versus small Fermi surface dichotomy, Fermi surface deconstruction (appearance of Fermi arcs), nodal versus antinodal physics, pseudogap(s), and kinks in the electronic dispersion. The resulting scenario envisages a smooth crossover between an ordinary weakly interacting metal sustaining weak, short-range antiferromagnetic correlations in the overdoped regime to an unconventional poor metal characterized by very strong, long-but-finite-range antiferromagnetic correlations leading to momentum-selective non-Fermi liquid features as well as to the opening of a pseudogap and to the striking differences between the nodal and the antinodal dynamics in the underdoped regime. © 2014 Adolfo Avella.

Guida M.,University of Salerno | Guida M.,CNR Institute of Neuroscience | Pulcini G.,CNR Institute of Neuroscience
Reliability Engineering and System Safety | Year: 2013

This paper proposes the family of non-stationary inverse Gamma processes for modeling state-dependent deterioration processes with nonlinear trend. The proposed family of processes, which is based on the assumption that the "inverse" time process is Gamma, is mathematically more tractable than previously proposed state-dependent processes, because, unlike the previous models, the inverse Gamma process is a time-continuous and state-continuous model and does not require discretization of time and state. The conditional distribution of the deterioration growth over a generic time interval, the conditional distribution of the residual life and the residual reliability of the unit, given the current state, are provided. Point and interval estimation of the parameters which index the proposed process, as well as of several quantities of interest, are also discussed. Finally, the proposed model is applied to the wear process of the liners of some Diesel engines which was previously analyzed and proved to be a purely state-dependent process. The comparison of the inferential results obtained under the competitor models shows the ability of the Inverse Gamma process to adequately model the observed state-dependent wear process. © 2013 Elsevier Ltd.

Del Mercato L.L.,University of Marburg | Del Mercato L.L.,CNR Institute of Neuroscience | Abbasi A.Z.,University of Marburg | Abbasi A.Z.,University of Toronto | And 2 more authors.
ACS Nano | Year: 2011

Multiplexed detection of analytes is a challenge for numerous medical and biochemical applications. Many fluorescent particulate devices are being developed as ratiometric optical sensors to measure the concentration of intracellular analytes. The response of these sensors is based on changes of the emission intensity of analyte-sensitive probes, entrapped into the carrier system, which depends on the concentration of a specific analyte. However, there are a series of technical limits that prevent their use for quantitative detection of several analytes in parallel (e.g., emission crosstalk between different sensor molecules). Here we demonstrate that double-wall barcoded sensor capsules can be used for multiplexed analysis of proton, sodium, and potassium ions. The sensor detection methodology is based on porous microcapsules which carry ion-sensitive probes in their inner cavity for ion detection and a unique QD barcode in their outermost wall as tag for identification of individual sensors. The engineering of QD barcodes to capsules walls represents a promising strategy for optical multianalyte determination. © 2011 American Chemical Society.

Giorgio M.,The Second University of Naples | Guida M.,University of Salerno | Pulcini G.,CNR Institute of Neuroscience
IIE Transactions (Institute of Industrial Engineers) | Year: 2011

Many technological units are subjected during their operating life to a gradual deterioration process that progressively degrades their characteristics until a failure occurs. Statisticians and engineers have almost always modeled degradation phenomena using independent increments processes, which imply that the degradation growth depends, at most, on the unit age. Only a few models have been proposed in which the degradation growth is assumed to depend on the current unit state. In many cases, however, both the current age and the current state of a unit can affect the degradation process. As such, this article proposes a degradation model in which the transition probabilities between unit states depend on both the current age and the current degradation level. Two applications based on real data sets are analyzed and discussed. Copyright © "IIE".

Linder J.,Norwegian University of Science and Technology | Cuoco M.,CNR Institute of Neuroscience | Cuoco M.,University of Salerno | Sudbo A.,Norwegian University of Science and Technology
Physical Review B - Condensed Matter and Materials Physics | Year: 2010

We study the physical properties of a half-metallic ferromagnet superconductor (HM S) bilayer, allowing for an arbitrary bulk pairing symmetry of the superconductor and spin-dependent processes at the interface. In particular, we study how the possibility of unconventional pairing such as p - and d -wave and a spin-active interface influence the (i) conductance spectra, (ii) proximity effect, and (iii) local density of states of such a bilayer. Our calculation is done both analytically and numerically in the ballistic limit, using both a continuum and lattice model. It is found that the spin-dependent phase shifts occurring at the HM S interface seriously influence all of the aforementioned phenomena. We explain our results in terms of Andreev reflection in the presence of a spin-active interface, allowing for both spin-filtering and spin-mixing processes. We demonstrate how the surface bound states induced by the anisotropy of the superconducting order parameter at the HM S interface are highly sensitive to these spin-dependent processes. Our results can be directly tested experimentally using scanning tunnel microscope measurements and/or point-contact spectroscopy. © 2010 The American Physical Society.

Capretti A.,Boston University | Capretti A.,CNR Institute of Neuroscience | Wang Y.,Boston University | Engheta N.,University of Pennsylvania | Dal Negro L.,Boston University
Optics Letters | Year: 2015

We experimentally demonstrate enhanced third-harmonic generation from indium tin oxide nanolayers at telecommunication wavelengths with an efficiency that is approximately 600 times larger than crystalline silicon (Si). The increased optical nonlinearity of the fabricated nanolayers is driven by their epsilon-near-zero response, which can be tailored on-demand in the near-infrared region. The present material platform is obtained without any specialized nanofabrication process and is fully compatible with the standard Si-planar technology. The proposed approach can lead to largely scalable and highly integrated optical nonlinearities in Si-integrated devices for information processing and optical sensing applications. © 2015 Optical Society of America.

Del Mercato L.L.,University of Marburg | Del Mercato L.L.,CNR Institute of Neuroscience | Abbasi A.Z.,University of Marburg | Parak W.J.,University of Marburg
Small | Year: 2011

Micrometer-sized polyelectrolyte capsules are synthesized, which have ion-sensitive fluorophores embedded in their cavities. As the membranes of the capsules are permeable to ions, the fluorescence of the capsules changed with the ion concentration. In particular, capsules sensitive to protons, sodium, potassium, and chloride ions are fabricated and their fluorescence response analyzed. In order to allow for ratiometric measurements, additional fluorophores whose emission do not depend on the ion concentration and which emit a different wavelength are co-embedded in the capsule cavities. Ion-sensitive polyelectrolyte capsules for protons, sodium, potassium, and chloride ions were fabricated by embedding sensor dye molecules, whose fluorescence intensity depends on the ion concentration, and reference dye molecules into their cavities. The fluorescence response of every sensor type to changes in ion concentration was quantitatively evaluated by ratiometric fluorescence spectroscopy and ratiometric fluorescence microscopy measurements. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Buono D.,University of Salerno | Nocerino G.,University of Salerno | Porzio A.,CNR Institute of Neuroscience | Porzio A.,University of Naples Federico II | Solimeno S.,University of Naples Federico II
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2012

Quantum properties are soon subject to decoherence once the quantum system interacts with the classical environment. In this paper we experimentally test how propagation losses, in a Gaussian channel, affect the bipartite Gaussian entangled state generated by a subthreshold type-II optical parametric oscillator. Experimental results are discussed in terms of different quantum markers, as teleportation fidelity, quantum discord, and mutual information, and continuous-variable (CV) entanglement criteria. To analyze state properties we have retrieved the composite system covariance matrix by a single homodyne detector. We experimentally found that, even in the presence of a strong decoherence, the generated state never disentangles and keeps breaking the quantum limit for the discord. This result proves that the class of CV entangled states discussed in this paper would allow, in principle, to realize quantum teleportation over an infinitely long Gaussian channel. © 2012 American Physical Society.

Karamshuk D.,IMT Institute for Advanced Studies | Boldrini C.,CNR Institute of Neuroscience | Conti M.,CNR Institute of Neuroscience | Passarella A.,CNR Institute of Neuroscience
IEEE Communications Magazine | Year: 2011

Mobile ad hoc networks enable communications between clouds of mobile devices without the need for a preexisting infrastructure. One of their most interesting evolutions are opportunistic networks, whose goal is to also enable communication in disconnected environments, where the general absence of an end-to-end path between the sender and the receiver impairs communication when legacy MANET networking protocols are used. The key idea of OppNets is that the mobility of nodes helps the delivery of messages, because it may connect, asynchronously in time, otherwise disconnected subnetworks. This is especially true for networks whose nodes are mobile devices (e.g., smartphones and tablets) carried by human users, which is the typical Opp- Nets scenario. In such a network where the movements of the communicating devices mirror those of their owners, finding a route between two disconnected devices implies uncovering habits in human movements and patterns in their connectivity (frequencies of meetings, average duration of a contact, etc.), and exploiting them to predict future encounters. Therefore, there is a challenge in studying human mobility, specifically in its application to OppNets research. In this article we review the state of the art in the field of human mobility analysis and present a survey of mobility models. We start by reviewing the most considerable findings regarding the nature of human movements, which we classify along the spatial, temporal, and social dimensions of mobility. We discuss the shortcomings of the existing knowledge about human movements and extend it with the notion of predictability and patterns. We then survey existing approaches to mobility modeling and fit them into a taxonomy that provides the basis for a discussion on open problems and further directions for research on modeling human mobility. © 2006 IEEE.

Ghosh N.,University of Ottawa | Rimoldi O.E.,CNR Institute of Neuroscience | Rimoldi O.E.,Imperial College London | Beanlands R.S.B.,University of Ottawa | And 2 more authors.
European Heart Journal | Year: 2010

In developed countries, coronary artery disease (CAD) continues to be a major cause of death and disability. Over the past two decades, positron emission tomography (PET) imaging has become more widely accessible for the management of ischemic heart disease. Positron emission tomography has also emerged as an important alternative perfusion imaging modality in the context of recent shortages of molybdenum-99/technetium-99m ( 99mTc). The clinical application of PET in ischaemic heart disease falls into two main categories: first, it is a well-established modality for evaluation of myocardial blood flow (MBF); second, it enables assessment of myocardial metabolism and viability in patients with ischaemic left ventricular dysfunction. The combined study of MBF and metabolism by PET has led to a better understanding of the pathophysiology of ischaemic heart disease. While there are potential future applications of PET for plaque and molecular imaging, as well as some clinical use in inflammatory conditions, this article provides an overview of the physical and biological principles behind PET imaging and its main clinical applications in cardiology, namely the assessment of MBF and metabolism. © 2010 The Author.

Marra P.,CNR Institute of Neuroscience | Citro R.,CNR Institute of Neuroscience | Citro R.,University of Salerno | Ortix C.,Leibniz Institute for Solid State and Materials Research
Physical Review B - Condensed Matter and Materials Physics | Year: 2015

A one-dimensional quantum charge pump transfers a quantized charge in each pumping cycle. This quantization is topologically robust, being analogous to the quantum Hall effect. The charge transferred in a fraction of the pumping period is instead generally unquantized. We show, however, that with specific symmetries in parameter space the charge transferred at well-defined fractions of the pumping period is quantized as integer fractions of the Chern number. We illustrate this in a one-dimensional Harper-Hofstadter model and show that the fractional quantization of the topological charge pumping is independent of the specific boundary conditions taken into account. We further discuss the relevance of this phenomenon for cold atomic gases in optical superlattices. © 2015 American Physical Society.

Boanini E.,University of Bologna | Torricelli P.,Rizzoli Orthopaedic Institute | Gazzano M.,CNR Institute of Neuroscience | Fini M.,Rizzoli Orthopaedic Institute | Bigi A.,University of Bologna
Biomaterials | Year: 2012

This study demonstrates that zoledronate containing hydroxyapatite nanocrystals (HA-ZOL) can be synthesized as a single crystalline phase up to a zoledronate content of about 7 wt% by direct synthesis in aqueous solution, at variance with what previously found for alendronate-hydroxyapatite nanocrystals (HA-AL). On increasing zoledronate incorporation, the length of the coherent crystalline domains and the crystal dimensions of hydroxyapatite decrease, whereas the specific surface area increases. Full profile fitting of the powder X-ray diffraction patterns does not indicate major structural modifications, but an increase of the hydroxyapatite unit cell, on increasing zoledronate content. These data, together with a structural similarity between hydroxyapatite and calcium zoledronate, suggest a preferential interaction between zoledronate and the hydroxyapatite faces parallel to the c-axis direction. Osteoblast-like MG-63 cells and human osteoclasts were cultured on HA-ZOL nanocrystals and as a comparison on HA-AL nanocrystals containing almost the same (about 7 wt%) bisphosphonate amount. The beneficial influence of bisphosphonates on osteoblast proliferation and differentiation is enhanced when the tests are performed in co-cultures. Similarly, the reduction of osteoclast proliferation and the increase of Caspase 3 production are dramatically enhanced in co-cultures, which highlight an even greater influence of HA-ZOL than HA-AL on osteoclast apoptosis. © 2011 Elsevier Ltd.

Schiro G.,University of Palermo | Caronna C.,European Synchrotron Radiation Facility | Caronna C.,SLAC | Natali F.,CNR Institute of Neuroscience | Cupane A.,University of Palermo
Journal of the American Chemical Society | Year: 2010

Elastic incoherent neutron scattering has been used to study the temperature dependence of the mean-square displacements of nonexchangeable hydrogen atoms in powders of a series of homomeric polypeptides (polyglycine, polyalanine, polyphenylalanine and polyisoleucine) in comparison with myoglobin at the same hydration level (h = 0.2). The aim of the work was to measure the dynamic behavior of different amino acid residues separately and assess the contribution of each type of side chain to the anharmonic dynamics of proteins. The results provide direct experimental evidence that the first anharmonic activation, at ∼150 K, is largely due to methyl group rotations entering the time window of the spectrometer used; however, contributions on the order of 10-20% from the motions of other groups (e.g., the phenolic ring and the methylene groups) are present. Our data also indicate that the dynamical transition occurring at ∼230 K can be attributed, at least at the hydration level investigated, mainly to motions involving backbone fluctuations. © 2010 American Chemical Society.

Casini G.,South African Council for Scientific and Industrial Research | Straccia U.,CNR Institute of Neuroscience
Journal of Artificial Intelligence Research | Year: 2013

Defeasible inheritance networks are a non-monotonic framework that deals with hierarchical knowledge. On the other hand, rational closure is acknowledged as a landmark of the preferential approach to non-monotonic reasoning. We will combine these two approaches and define a new non-monotonic closure operation for propositional knowledge bases that combines the advantages of both. Then we redefine such a procedure for Description Logics (DLs), a family of logics well-suited to model structured information. In both cases we will provide a simple reasoning method that is built on top of the classical entailment relation and, thus, is amenable of an implementation based on existing reasoners. Eventually, we evaluate our approach on well-known landmark test examples. © 2013 AI Access Foundation.

Mammano F.,University of Padua | Mammano F.,Instituto Veneto Of Medicina Molecolare | Mammano F.,CNR Institute of Neuroscience
Seminars in Cell and Developmental Biology | Year: 2013

Hearing relies on a sensitive mechanoelectrical transduction process in the cochlea of the inner ear. The cochlea contains sensory, secretory, neural, supporting and epithelial cells which are all essential to the sound transduction process. It is well known that a complex extracellular purinergic signaling system contributes to cochlear homeostasis, altering cochlear sensitivity and neural output via ATP-gated ion channels (P2X receptors) and G protein-coupled P2Y receptors. This review focuses on the emerging roles of ATP that are currently under investigation in the developing sensory epithelium, with particular emphasis on the link between ATP release, Ca2+ signaling, the expression and function of gap junction proteins connexin26 and connexin30, and the acquisition of hearing. © 2012 Elsevier Ltd.

Brzezicki W.,Jagiellonian University | Brzezicki W.,CNR Institute of Neuroscience | Brzezicki W.,University of Salerno | Oles A.M.,Jagiellonian University | And 3 more authors.
Physical Review X | Year: 2015

We investigate the changes in spin and orbital patterns induced by magnetic transition-metal ions without an orbital degree of freedom doped in a strongly correlated insulator with spin-orbital order. In this context, we study the 3d ion substitution in 4d transition-metal oxides in the case of 3d3 doping at either 3d2 or 4d4 sites, which realizes orbital dilution in a Mott insulator. Although we concentrate on this doping case as it is known experimentally and more challenging than other oxides due to finite spin-orbit coupling, the conclusions are more general. We derive the effective 3d - 4d (or 3d - 3d) superexchange in a Mott insulator with different ionic valencies, underlining the emerging structure of the spin-orbital coupling between the impurity and the host sites, and demonstrate that it is qualitatively different from that encountered in the host itself. This derivation shows that the interaction between the host and the impurity depends in a crucial way on the type of doubly occupied t2g orbital. One finds that in some cases, due to the quench of the orbital degree of freedom at the 3d impurity, the spin and orbital order within the host is drastically modified by doping. The impurity either acts as a spin defect accompanied by an orbital vacancy in the spin-orbital structure when the host-impurity coupling is weak or favors doubly occupied active orbitals (orbital polarons) along the 3d - 4d bond leading to antiferromagnetic or ferromagnetic spin coupling. This competition between different magnetic couplings leads to quite different ground states. In particular, for the case of a finite and periodic 3d atom substitution, it leads to striped patterns either with alternating ferromagnetic or antiferromagnetic domains or with islands of saturated ferromagnetic order. We find that magnetic frustration and spin degeneracy can be lifted by the quantum orbital flips of the host, but they are robust in special regions of the incommensurate phase diagram. Orbital quantum fluctuations modify quantitatively spin-orbital order imposed by superexchange. In contrast, the spin-orbit coupling can lead to anisotropic spin and orbital patterns along the symmetry directions and cause a radical modification of the order imposed by the spin-orbital superexchange. Our findings are expected to be of importance for future theoretical understanding of experimental results for 4d transition-metal oxides doped with 3d3 ions. We suggest how the local or global changes of the spin-orbital order induced by such impurities could be detected experimentally.

Andreev S.V.,Montpellier University | Varlamov A.A.,CNR Institute of Neuroscience | Kavokin A.V.,University of Southampton | Kavokin A.V.,Saint Petersburg State University
Physical Review Letters | Year: 2014

We address, theoretically, the puzzling similarity observed in the thermodynamic behavior of independent clouds of cold dipolar excitons in coupled semiconductor quantum wells. We argue that the condensation of self-trapped exciton gas starts at the same critical temperature in all traps due to the specific scaling rule. As a consequence of the reduced dimensionality of the system, the scaling parameters appear to be insensitive to disorder. © 2014 American Physical Society.

Belshaw L.,Queen's University of Belfast | Calegari F.,Polytechnic of Milan | Duffy M.J.,Queen's University of Belfast | Trabattoni A.,Polytechnic of Milan | And 3 more authors.
Journal of Physical Chemistry Letters | Year: 2012

We present the first direct measurement of ultrafast charge migration in a biomolecular building block - the amino acid phenylalanine. Using an extreme ultraviolet pulse of 1.5 fs duration to ionize molecules isolated in the gas phase, the location of the resulting hole was probed by a 6 fs visible/near-infrared pulse. By measuring the yield of a doubly charged ion as a function of the delay between the two pulses, the positive hole was observed to migrate to one end of the cation within 30 fs. This process is likely to originate from even faster coherent charge oscillations in the molecule being dephased by bond stretching which eventually localizes the final position of the charge. This demonstration offers a clear template for observing and controlling this phenomenon in the future. © 2012 American Chemical Society.

Camici P.G.,San Raffaele Scientific Institute | Rimoldi O.E.,CNR Institute of Neuroscience | Gaemperli O.,Interventional Imaging | Libby P.,Brigham and Women's Hospital
European Heart Journal | Year: 2012

Over the last several decades, basic cardiovascular research has significantly enhanced our understanding of pathobiological processes leading to formation, progression, and complications of atherosclerotic plaques. By harnessing these advances in cardiovascular biology, imaging has advanced beyond its traditional anatomical domains to a tool that permits probing of particular molecular structures to image cellular behaviour and metabolic pathways involved in atherosclerosis. From the nascent atherosclerotic plaque to the death of inflammatory cells, several potential molecular and micro-anatomical targets for imaging with particular selective imaging probes and with a variety of imaging modalities have emerged from preclinical and animal investigations. Yet, substantive barriers stand between experimental use and wide clinical application of these novel imaging strategies. Each of the imaging modalities described herein faces hurdles-for example, sensitivity, resolution, radiation exposure, reproducibility, availability, standardization, or costs. This review summarizes the published literature reporting on functional imaging of vascular inflammation in atherosclerotic plaques emphasizing those techniques that have the greatest and/or most immediate potential for broad application in clinical practice. The prospective evaluation of these techniques and standardization of protocols by multinational networks could serve to determine their added value in clinical practice and guide their development and deployment. © 2012 The Author.

Nativio R.,University of Cambridge | Sparago A.,CNR Institute of Neuroscience | Ito Y.,University of Cambridge | Weksberg R.,Hospital for Sick Children Research Institute | And 3 more authors.
Human Molecular Genetics | Year: 2011

Hyper- and hypomethylation at the IGF2-H19 imprinting control region (ICR) result in reciprocal changes in IGF2-H19 expression and the two contrasting growth disorders, Beckwith-Wiedemann syndrome (BWS) and Silver-Russell syndrome (SRS). DNA methylation of the ICR controls the reciprocal imprinting of IGF2 and H19 by preventing the binding of the insulator protein, CTCF. We here show that local changes in histone modifications and CTCF-cohesin binding at the ICR in BWS and SRS together with DNA methylation correlate with the higher order chromatin structure at the locus. In lymphoblastoid cells from control individuals, we found the repressive histone H3K9me3 and H4K20me3 marks associated with the methylated paternal ICR allele and the bivalent H3K4me2/H3K27me3 mark together with H3K9ac and CTCF-cohesin associated with the non-methylated maternal allele. In patient-derived cell lines, the mat/pat asymmetric distribution of these epigenetic marks was lost with H3K9me3 and H4K20me3 becoming biallelic in the BWS and H3K4me2, H3K27me3 and H3K9ac together with CTCF-cohesin becoming biallelic in the SRS. We further show that in BWS and SRS cells, there is opposing chromatin looping conformation mediated by CTCF-cohesin binding sites surrounding the locus. In normal cells, lack of CTCF-cohesin binding at the paternal ICR is associated with monoallelic interaction between two CTCF sites flanking the locus. CTCF-cohesin binding at the maternal ICR blocks this interaction by associating with the CTCF site downstream of the enhancers. The two alternative chromatin conformations are differently favoured in BWS and SRS likely predisposing the locus to the activation of IGF2 or H19, respectively. © The Author 2011. Published by Oxford University Press.

d'Acierno A.,CNR Institute of Neuroscience | Facchiano A.,CNR Institute of Neuroscience | Marabotti A.,University of Salerno
Human Mutation | Year: 2014

Knowledge of the impact of variations on protein structure can enhance the comprehension of the mechanisms of genetic diseases related to that protein. Here, we present a new version of GALT Protein Database, a Web-accessible data repository for the storage and interrogation of structural effects of variations of the enzyme galactose-1-phosphate uridylyltransferase (GALT), the impairment of which leads to classic Galactosemia, a rare genetic disease. This new version of this database now contains the models of 201 missense variants of GALT enzyme, including heterozygous variants, and it allows users not only to retrieve information about the missense variations affecting this protein, but also to investigate their impact on substrate binding, intersubunit interactions, stability, and other structural features. In addition, it allows the interactive visualization of the models of variants collected into the database. We have developed additional tools to improve the use of the database by nonspecialized users. This Web-accessible database (http://bioinformatica.isa.cnr.it/GALT/GALT2.0) represents a model of tools potentially suitable for application to other proteins that are involved in human pathologies and that are subjected to genetic variations. © 2014 WILEY PERIODICALS, INC.

Hutchison J.A.,University of Strasbourg | Liscio A.,CNR Institute of Neuroscience | Schwartz T.,University of Strasbourg | Canaguier-Durand A.,University of Strasbourg | And 4 more authors.
Advanced Materials | Year: 2013

The tuning of the molecular material work-function via strong coupling with vacuum electromagnetic fields is demonstrated. Kelvin probe microscopy extracts the surface potential (SP) changes of a photochromic molecular film on plasmonic hole arrays and inside Fabry-Perot cavities. Modulating the optical cavity resonance or the photochromic film effectively tunes the work-function, suggesting a new tool for tailoring material properties. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cascini L.,University of Salerno | Fornaro G.,CNR Institute of Neuroscience | Peduto D.,University of Salerno
Engineering Geology | Year: 2010

A proper analysis of slow-moving landslides calls for several efforts aiming at their characterization and mapping. Considering the uncertainties related to the landslide inventory maps the integration of conventional techniques with remote sensing data, such as differential SAR interferometry (DInSAR), can furnish a valuable contribution in a number of case studies. However, standardized procedures for the interpretation and the confident use of DInSAR data, according to landslide zoning developments, have not been fully investigated and validated, although algorithms for image processing have become more and more sophisticated. This work addresses a new methodology for the use of DInSAR data, at both full- and low-resolutions, in landslide analyses at different scales via the integration of remote sensing data with simple geomorphological models and geometric considerations. The methodology is tested inside a well documented area in Central-Southern Italy where an advanced dataset on base and thematic maps is available. © 2010 Elsevier B.V. All rights reserved.

Biffi C.A.,CNR Institute of Neuroscience | Previtali B.,Polytechnic of Milan
International Journal of Advanced Manufacturing Technology | Year: 2013

Pulsed wave fibre lasers are becoming a popular industrial tool in microprocessing due to their many positive features, such as high beam quality, high reliability and high productivity, which are fundamental to machining small, precise features of industrial applications. However, the lasers' use in the machining of ultraprecise features, such as small holes, is hindered by the fact that commercial pulsed wave fibre lasers commonly operate with pulse durations in the nanosecond regime. Such long pulse durations mean that the material is thermally removed, which results in the production of a melted layer and thermal damage in the bulk material. Consequently, the typical thermal defects of the melting regime, such as spattering of recast material around the hole, taper, heat-affected zone and poor hole circularity, are found in materials machined with these lasers. This paper proposes a design for an innovative nozzle that combines the high productivity of nanosecond fibre lasers with an improvement in the quality of the machined holes by reducing the spatter production in titanium laser percussion drilling. The innovative nozzle is based on the suction effect created by the Venturi principle that prevents the deposition of melted and vaporised material on the workpiece surface. The influence of the nozzle configuration and shielding gas on hole quality is investigated after the laser percussion drilling of 0.5-mm-thick titanium sheets, in which the process conditions that allow maximum productivity are used. The innovative nozzle produces a remarkable decrease in spatter on the entrance hole surface without affecting the other quality features, such as hole diameter, circularity and taper, while preserving the high productivity obtainable with a standard nozzle. © 2012 Springer-Verlag London Limited.

Jeong H.,Seoul National University | Zavatta A.,CNR Institute of Neuroscience | Zavatta A.,University of Florence | Kang M.,Seoul National University | And 8 more authors.
Nature Photonics | Year: 2014

Entanglement between quantum and classical objects is of special interest in the context of fundamental studies of quantum mechanics and potential applications for quantum information processing. In quantum optics, single photons are treated as light quanta while coherent states are considered the most classical of pure states. Recently, entanglement between a single photon and a coherent state in a free-travelling field was identified as a useful resource for optical quantum information processing. However, the extreme difficulty involved in generating such states was highlighted, as it requires clean cross-Kerr nonlinearities. Here, we devise and experimentally demonstrate a scheme to generate such hybrid entanglement by implementing a superposition of two distinct quantum operations. The generated states clearly show entanglement between the two different types of states. Our work opens the way to the generation of hybrid entanglement of greater size and the development of efficient quantum information processing using a new type of qubit. © 2014 Macmillan Publishers Limited.

Giovannetti V.,CNR Institute of Neuroscience | Garcia-Patron R.,Free University of Colombia | Garcia-Patron R.,Max Planck Institute of Quantum Optics | Cerf N.J.,Free University of Colombia | Holevo A.S.,National Research University Higher School of Economics
Nature Photonics | Year: 2014

Optical channels, such as fibres or free-space links, are ubiquitous in today's telecommunication networks. They rely on the electromagnetic field associated with photons to carry information from one point to another in space. A complete physical model of these channels must necessarily take quantum effects into account to determine their ultimate performances. Single-mode, phase-insensitive bosonic Gaussian channels have been extensively studied over past decades, given their importance for practical applications. In spite of this, a long-standing unsolved conjecture on the optimality of Gaussian encodings has prevented finding their classical communication capacity. Here, this conjecture is solved by proving that the vacuum state achieves the minimum output entropy of these channels. This establishes the ultimate achievable bit rate under an energy constraint, as well as the long awaited proof that the single-letter classical capacity of these channels is additive. © 2014 Macmillan Publishers Limited. All rights reserved.

Bobillo F.,University of Zaragoza | Straccia U.,CNR Institute of Neuroscience
Information Sciences | Year: 2012

Description logics (DLs) are a family of logics for representing structured knowledge which have proved to be very useful as ontology languages. Classical DLs are not suitable to represent vague pieces of information. The attempts to achieve a solution have led to the birth of fuzzy DLs and rough DLs. In this work, we provide a simple solution to join these two formalisms and define a fuzzy rough DL. This logic is more general than other related approaches, including tight and loose fuzzy rough approximations and being independent of the fuzzy logic operators considered. We show the usefulness of our approach by presenting some uses case, and we also describe how to extend two reasoning algorithms for fuzzy DLs, which are implemented in the fuzzy DL reasoners fuzzyDL and DeLorean. © 2011 Elsevier Inc. All rights reserved.

Ostilli M.,International Islamic University Malaysia | Ostilli M.,CNR Institute of Neuroscience
Physica A: Statistical Mechanics and its Applications | Year: 2012

We review critically the concepts and the applications of Cayley Trees and Bethe Lattices in statistical mechanics in a tentative effort to remove widespread misuse of these simple, but yet importantand differentideal graphs. We illustrate, in particular, two rigorous techniques to deal with Bethe Lattices, based respectively on self-similarity and on the Kolmogorov consistency theorem, linking the latter with the Cavity and Belief Propagation methods, more known to the physics community. © 2012 Elsevier B.V. All rights reserved.

Amato M.,CNRS Fundamental Electronics Institute | Palummo M.,European Theoretical Spectroscopy Facility | Rurali R.,CSIC - Institute of Materials Science | Ossicini S.,CNR Institute of Neuroscience | Ossicini S.,University of Modena and Reggio Emilia
Chemical Reviews | Year: 2014

The different employed growth techniques for silicon-germanium (SiGe) nanowires, their morphology and structural properties were discussed. Significant progresses toward a precise control of the NWs composition were subsequently made in chemical vapor deposition using an appropriate gas inlet ratio in an optimum temperature range or tuning the total growth pressure. Long and straight, without significant tapering, SiGe NWs were obtained through the use of additional gases, other than the usual precursor. Regarding the morphology both axial and radial heterostructures have been reported so far. When laser ablation and CVD techniques were combined, axially modulated SiGe NWs of different diameters were produced. A better control of the interface sharpness, of the order of 1nm, has been then reached combining vapor-liquid-solid (VLS) and vapor-solid-solid (VSS) growth. It is clear that SiGe nanowires will play an important role in the next generation of advanced miniaturized devices.

Bobillo F.,University of Zaragoza | Straccia U.,CNR Institute of Neuroscience
Information Sciences | Year: 2011

Fuzzy Description Logics are a formalism for the representation of structured knowledge affected by imprecision or vagueness. They have become popular as a language for fuzzy ontology representation. To date, most of the work in this direction has focused on the so-called Zadeh family of fuzzy operators (or fuzzy logic), which has several limitations. In this paper, we generalize existing proposals and show how to reason with a fuzzy extension of the logic SROIQ, the logic behind the language OWL 2, under finitely many-valued Łukasiewicz fuzzy logic. We show for the first time that it is decidable over a finite set of truth values by presenting a reasoning preserving procedure to obtain a non-fuzzy representation for the logic. This reduction makes it possible to reuse current representation languages as well as currently available reasoners for ontologies. © 2010 Elsevier Inc. All rights reserved.

Torres A.,University of Barcelona | Blasi F.,University of Milan | Peetermans W.E.,University Hospital | Viegi G.,CNR Institute of Clinical Physiology | And 2 more authors.
European Journal of Clinical Microbiology and Infectious Diseases | Year: 2014

The purpose of this paper was to generate up-to-date information on the aetiology of community-acquired pneumonia (CAP) and its antibiotic management in adults across Europe. Structured searches of PubMed identified information on the aetiology of CAP and its antibiotic management in individuals aged >15 years across Europe. We summarise the data from 33 studies published between January 2005 and July 2012 that reported on the pathogens identified in patients with CAP and antibiotic treatment in patients with CAP. Streptococcus pneumoniae was the most commonly isolated pathogen in patients with CAP and was identified in 12.0-85.0 % of patients. Other frequently identified pathogens found to cause CAP were Haemophilus influenzae, Gram-negative enteric bacilli, respiratory viruses and Mycoplasma pneumoniae. We found several age-related trends: S. pneumoniae, H. influenzae and respiratory viruses were more frequent in elderly patients aged ≥65 years, whereas M. pneumoniae was more frequent in those aged <65 years. Antibiotic monotherapy was more frequent than combination therapy, and beta-lactams were the most commonly prescribed antibiotics. Hospitalised patients were more likely than outpatients to receive combination antibiotic therapy. Limited data on antibiotic resistance were available in the studies. Penicillin resistance of S. pneumoniae was reported in 8.4-20.7 % of isolates and erythromycin resistance was reported in 14.7-17.1 % of isolates. Understanding the aetiology of CAP and the changing pattern of antibiotic resistance in Europe, together with an increased awareness of the risk factors for CAP, will help clinicians to identify those patients most at risk of developing CAP and provide guidance on the most appropriate treatment. © 2014 The Author(s).

Hassan M.M.,Agresearch Ltd. | McLaughlin J.R.,CNR Institute of Neuroscience
ACS Applied Materials and Interfaces | Year: 2013

Chemical vapor deposition (CVD) polymerization is a useful technique because of the possibility of forming very thin film of pure polymers on substrates with any geometric shape. In this work, thin films of poly(methyl methacrylate) or PMMA were formed on the surfaces of wool fabrics by a CVD polymerization process. Various polymerization initiators including dicumyl peroxide, tert-butyl peroxide, and potassium peroxydisulfate have been investigated to polymerize methyl methacrylate onto the surfaces of wool by the CVD polymerization. The wool fabrics were impregnated with initiators and were then exposed to MMA monomer vapor under vacuum at the boiling temperature of the monomer. Wool fabrics with vapor-deposited PMMA surfaces were characterized by elemental analysis, TGA, FTIR, disperse dye absorption, contact angles measurement, AFM, and SEM. PMMA-coated wool fabrics showed higher contact angle and absorbed more dyes than that of the control wool. It was evident from the results obtained by various characterization techniques that MMA was successfully polymerized and formed thin films on the surfaces of wool fabrics by all initiators investigated but the best results were achieved with tert-butyl peroxide. © 2013 American Chemical Society.

Di Giulio M.,Charles University | Di Giulio M.,CNR Institute of Neuroscience
Biochimie | Year: 2012

The properties, historical and empirical observations of a model of the origin of the tRNA molecule are discussed. This model would predict that this molecule originated by means of the assembly of two hairpin-like structures of RNA. The conclusion is that the model possesses a relevant part of the truth on the origin of the tRNA molecule. © 2011 Elsevier Masson SAS. All rights reserved.

Hancock S.P.,University of California at Los Angeles | Ghane T.,CNR Institute of Neuroscience | Cascio D.,University of California at Los Angeles | Rohs R.,University of Southern California | And 3 more authors.
Nucleic Acids Research | Year: 2013

The width of the DNA minor groove varies with sequence and can be a major determinant of DNA shape recognition by proteins. For example, the minor groove within the center of the Fis-DNA complex narrows to about half the mean minor groove width of canonical B-form DNA to fit onto the protein surface. G/C base pairs within this segment, which is not contacted by the Fis protein, reduce binding affinities up to 2000-fold over A/T-rich sequences. We show here through multiple X-ray structures and binding properties of Fis-DNA complexes containing base analogs that the 2-amino group on guanine is the primary molecular determinant controlling minor groove widths. Molecular dynamics simulations of free-DNA targets with canonical and modified bases further demonstrate that sequence-dependent narrowing of minor groove widths is modulated almost entirely by the presence of purine 2-amino groups. We also provide evidence that protein-mediated phosphate neutralization facilitates minor groove compression and is particularly important for binding to non-optimally shaped DNA duplexes. © 2013 The Author(s) 2013. Published by Oxford University Press.

Amoretti A.,University of Genoa | Amoretti A.,National Institute of Nuclear Physics, Italy | Braggio A.,University of Genoa | Braggio A.,CNR Institute of Neuroscience | And 3 more authors.
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

We provide an analytical derivation of the thermoelectric transport coefficients of the simplest momentum-dissipating model in gauge/gravity where the lack of momentum conservation is realized by means of explicit graviton mass in the bulk. We rely on the procedure recently described by Donos and Gauntlett for holographic models where momentum dissipation is realized through nontrivial scalars. The analytical approach confirms and supports the results found previously by means of numerical computations and the associated holographic renormalization procedure. Importantly, it also provides a precise identification of the range of validity of the hydrodynamic approximation. © 2015 American Physical Society.

Harris J.,University of Ottawa | Grillo V.,CNR Institute of Neuroscience | Mafakheri E.,University of Modena and Reggio Emilia | Gazzadi G.C.,CNR Institute of Neuroscience | And 5 more authors.
Nature Physics | Year: 2015

The study of structured optical waves has enhanced our understanding of light and numerous experimental methods now enable the control of the angular momentum and radial distributions. Recently, these wavestructuring techniques have been successfully applied to the generation and shaping of electron beams, leading to promising practical and fundamental advances. Here, we discuss recent progress in the emerging field of electron beam shaping, and explore the unique attributes that distinguish electron beams from their photonic analogues. © 2015 Macmillan Publishers Limited.

Ghosh P.,Abdus Salam International Center For Theoretical Physics | Gebauer R.,Abdus Salam International Center For Theoretical Physics | Gebauer R.,CNR Institute of Neuroscience
Journal of Chemical Physics | Year: 2010

Electronic charge transfer plays an important role in novel nanostructured photovoltaic materials. Standard density functional theory (DFT) as well as time-dependent DFT severely underestimate the excitation energies related to such transitions. For the paradigmatic case of a donor-acceptor dyad formed by a zinc-porphyrin donor and a C70 fullerene acceptor these shortcomings are illustrated. A better quantitative estimate of the charge transfer energy is obtained from constrained DFT which is applied to this system in a novel implementation based on a penalty functional. © 2010 American Institute of Physics.

Rizza C.,University of Insubria | Rizza C.,CNR Institute of Neuroscience | Ciattoni A.,CNR Institute of Neuroscience | Spinozzi E.,University of Rome La Sapienza | And 2 more authors.
Optics Letters | Year: 2012

We theoretically consider infrared-driven hyperbolic metamaterials able to spatially filter terahertz (THz) radiation. The metamaterial is a slab made of alternating semiconductor and dielectric layers whose homogenized uniaxial response, at THz frequencies, shows principal permittivities of different signs. The gap provided by metamaterial hyperbolic dispersion allows the slab to stop spatial frequencies within a bandwidth tunable by changing the infrared radiation intensity. We numerically prove the device functionality by resorting to full wave simulation coupled to the dynamics of charge carries photoexcited by infrared radiation in semiconductor layers. © 2012 Optical Society of America.

Holevo A.S.,Gubkin Russian State University of Oil and Gas | Giovannetti V.,CNR Institute of Neuroscience
Reports on Progress in Physics | Year: 2012

One of the major achievements of the recently emerged quantum information theory is the introduction and thorough investigation of the notion of a quantum channel which is a basic building block of any data-transmitting or data-processing system. This development resulted in an elaborated structural theory and was accompanied by the discovery of a whole spectrum of entropic quantities, notably the channel capacities, characterizing information- processing performance of the channels. This paper gives a survey of the main properties of quantum channels and of their entropic characterization, with a variety of examples for finite-dimensional quantum systems. We also touch upon the 'continuous-variables' case, which provides an arena for quantum Gaussian systems. Most of the practical realizations of quantum information processing were implemented in such systems, in particular based on principles of quantum optics. Several important entropic quantities are introduced and used to describe the basic channel capacity formulae. The remarkable role of specific quantum correlations - entanglement - as a novel communication resource is stressed. © 2012 IOP Publishing Ltd.

McPartland J.M.,GW Pharmaceuticals | Duncan M.,GW Pharmaceuticals | Di Marzo V.,CNR Institute of Neuroscience | Pertwee R.G.,University of Aberdeen
British Journal of Pharmacology | Year: 2015

Based upon evidence that the therapeutic properties of Cannabis preparations are not solely dependent upon the presence of Δ9-tetrahydrocannabinol (THC), pharmacological studies have been recently carried out with other plant cannabinoids (phytocannabinoids), particularly cannabidiol (CBD) and Δ9-tetrahydrocannabivarin (THCV). Results from some of these studies have fostered the view that CBD and THCV modulate the effects of THC via direct blockade of cannabinoid CB1 receptors, thus behaving like first-generation CB1 receptor inverse agonists, such as rimonabant. Here, we review in vitro and ex vivo mechanistic studies of CBD and THCV, and synthesize data from these studies in a meta-analysis. Synthesized data regarding mechanisms are then used to interpret results from recent pre-clinical animal studies and clinical trials. The evidence indicates that CBD and THCV are not rimonabant-like in their action and thus appear very unlikely to produce unwanted CNS effects. They exhibit markedly disparate pharmacological profiles particularly at CB1 receptors: CBD is a very low-affinity CB1 ligand that can nevertheless affect CB1 receptor activity in vivo in an indirect manner, while THCV is a high-affinity CB1 receptor ligand and potent antagonist in vitro and yet only occasionally produces effects in vivo resulting from CB1 receptor antagonism. THCV has also high affinity for CB2 receptors and signals as a partial agonist, differing from both CBD and rimonabant. These cannabinoids illustrate how in vitro mechanistic studies do not always predict in vivo pharmacology and underlie the necessity of testing compounds in vivo before drawing any conclusion on their functional activity at a given target. © 2014 The British Pharmacological Society.

Abedinpour S.H.,Institute for Advanced Studies in Basic Sciences | Abedinpour S.H.,Institute for Research in Fundamental Sciences | Asgari R.,Institute for Research in Fundamental Sciences | Tanatar B.,Bilkent University | Polini M.,CNR Institute of Neuroscience
Annals of Physics | Year: 2014

We study the ground-state properties of a two-dimensional spin-polarized fluid of dipolar fermions within the Euler-Lagrange Fermi-hypernetted-chain approximation. Our method is based on the solution of a scattering Schrödinger equation for the "pair amplitude" g(r), where g ( r) is the pair distribution function. A key ingredient in our theory is the effective pair potential, which includes a bosonic term from Jastrow-Feenberg correlations and a fermionic contribution from kinetic energy and exchange, which is tailored to reproduce the Hartree-Fock limit at weak coupling. Very good agreement with recent results based on quantum Monte Carlo simulations is achieved over a wide range of coupling constants up to the liquid-to-crystal quantum phase transition. Using the fluctuation-dissipation theorem and a static approximation for the effective inter-particle interactions, we calculate the dynamical density-density response function, and furthermore demonstrate that an undamped zero-sound mode exists for any value of the interaction strength, down to infinitesimally weak couplings. © 2013 Elsevier Inc.

Grillo V.,CNR Institute of Neuroscience | Karimi E.,University of Ottawa | Gazzadi G.C.,CNR Institute of Neuroscience | Frabboni S.,CNR Institute of Neuroscience | And 4 more authors.
Physical Review X | Year: 2014

Almost 30 years ago, Durnin discovered that an optical beam with a transverse intensity profile in the form of a Bessel function of the first order is immune to the effects of diffraction. Unlike most laser beams, which spread upon propagation, the transverse distribution of these Bessel beams remains constant. Electrons also obey a wave equation (the Schrödinger equation), and therefore Bessel beams also exist for electron waves. We generate an electron Bessel beam by diffracting electrons from a nanoscale phase hologram. The hologram imposes a conical phase structure on the electron wave-packet spectrum, thus transforming it into a conical superposition of infinite plane waves, that is, a Bessel beam. We verify experimentally that these beams can propagate for 0.6 m without measurable spreading and can also reconstruct their intensity distributions after being partially obstructed by an obstacle. Finally, we show by numerical calculations that the performance of an electron microscope can be increased dramatically through use of these beams.

Amoretti A.,University of Genoa | Braggio A.,CNR Institute of Neuroscience | Maggiore N.,University of Genoa | Magnoli N.,University of Genoa | Musso D.,Abdus Salam International Center For Theoretical Physics
Journal of High Energy Physics | Year: 2014

Abstract: We present a systematic definition and analysis of the thermo-electric linear response in gauge/gravity systems focusing especially on models with massive gravity in the bulk and therefore momentum dissipation in the dual field theory. A precise treatment of finite counter-terms proves to be essential to yield a consistent physical picture whose hydrodynamic and beyond-hydrodynamics behaviors noticeably match with field theoretical expectations. The model furnishes a possible gauge/gravity description of the crossover from the quantum-critical to the disorder-dominated Fermi-liquid behaviors, as expected in graphene. © 2014, The Author(s).

Palummo M.,European Theoretical Spectroscopy Facility | Amato M.,CNR Institute of Neuroscience | Ossicini S.,European Theoretical Spectroscopy Facility
Physical Review B - Condensed Matter and Materials Physics | Year: 2010

The self-energy and electron-hole interaction corrections to the one-particle approximation for SiGe nanowires have been calculated for different geometries and diameters. We show that, at fixed nanowire diameter and orientation, the self-energy corrections for the SiGe nanowires can be obtained as a weighted average, on the relative composition of one type of atom with respect to the total numbers of atoms in the unit cell, of the corrections for the pure (Si and Ge) nanowires, thus circumventing cumbersome computations and allowing a direct and practical determination of the electronic band gap. Moreover we show that particular geometrical configurations are at the origin of an enhancement of the optical oscillator strength that should be important for optoelectronic applications. © 2010 The American Physical Society.

Chio A.,University of Turin | Pagani M.,CNR Institute of Neuroscience | Pagani M.,Karolinska University Hospital | Agosta F.,Vita-Salute San Raffaele University | And 4 more authors.
The Lancet Neurology | Year: 2014

In the past two decades, structural and functional neuroimaging findings have greatly modified longstanding notions regarding the pathophysiology of amyotrophic lateral sclerosis (ALS). Neuroimaging studies have shown that anatomical and functional lesions spread beyond precentral cortices and corticospinal tracts, to include the corpus callosum; frontal, sensory, and premotor cortices; thalamus; and midbrain. Both MRI and PET studies have shown early and diffuse loss of inhibitory cortical interneurons in the motor cortex (increased levels of functional connectivity and loss of GABAergic neurons, respectively) and diffuse gliosis in white-matter tracts. In ALS endophenotypes, neuroimaging has also shown a diverse spreading of lesions and a dissimilar impairment of functional and structural connections. A possible role of PET in the diagnosis of ALS has recently been proposed. However, most neuroimaging studies have pitfalls, such as a small number and poor clinical characterisation of patients, absence of adequate controls, and scarcity of longitudinal assessments. Studies involving international collaborations, standardised assessments, and large patient cohorts will overcome these shortcomings and provide further insight into the pathogenesis of ALS. © 2014 Elsevier Ltd.

Voitchovsky K.,Massachusetts Institute of Technology | Kuna J.J.,Massachusetts Institute of Technology | Contera S.A.,University of Oxford | Tosatti E.,International School for Advanced Studies | And 4 more authors.
Nature Nanotechnology | Year: 2010

Solid-liquid interfaces play a fundamental role in surface electrochemistry, catalysis, wetting, self-assembly and biomolecular functions. The interfacial energy determines many of the properties of such interfaces, including the arrangement of the liquid molecules at the surface of the solid. Diffraction techniques are often used to investigate the structure of solid-liquid interfaces, but measurements of irregular or inhomogeneous interfaces remain challenging. Here, we report atomic-and molecular-resolution images of various organic and inorganic samples in liquids, obtained with a commercial atomic force microscope operated dynamically with small-amplitude modulation. This approach uses the structured liquid layers close to the solid to enhance lateral resolution. We propose a model to explain the mechanism dominating the image formation, and show that the energy dissipated during this process is related to the interfacial energy through a readily achievable calibration curve. Our topographic images and interfacial energy maps could provide insights into important interfaces. © 2010 Macmillan Publishers Limited. All rights reserved.

Torrente M.M.,University of Sannio | Milia A.,CNR Institute of Neuroscience
Bulletin of Volcanology | Year: 2013

By means of information technology, 3D digital geologic models are increasingly the best methods of constraining interpretations of geology at depth. Visualization in three dimensions has allowed us to develop solutions that explain the stratigraphic and structural complexity of the Campania margin of the Eastern Tyrrhenian Sea, especially the lateral relationships among volcanoes and underlying normal faults. Using seismic and sequence stratigraphy and structural geology approaches in a dedicated GIS environment, we interpreted a seismic grid and investigated a subsurface volcanic field in Gaeta Bay (off Campi Flegrei) located within the Campania margin. The Gaeta Bay basin fill is characterized by several volcanic units that were analyzed using 2D structure contour maps and isochron maps. These volcanoes are comparable in size to the edifices of Campi Flegrei, Vesuvius, and the submerged volcanoes of the Bay of Naples. Their age spans from the Lower Pleistocene for the isolated V0 volcano sited in Central Gaeta Bay to 0.4-0.1 Ma for the volcanic field of southern Gaeta Bay. The study of the interplay between volcanic units and faults allowed us to distinguish (1) the oldest fault buried by the Lower Pleistocene V0 volcano in Central Gaeta Bay; (2) a normal fault swarm NE-SW that in the Middle Pleistocene gave rise to a half-graben filled by the V1-V5 volcanic field in southern Gaeta Bay; and (3) post-0.4 Ma normal faults that downthrow the V1 and V3 volcanoes. We correlated the >1,500-m-thick Late Quaternary volcanoes of southern Gaeta Bay to the buried lava volcanoes interlayered with volcanoclastic deposits drilled at Campi Flegrei geothermal wells. © 2013 Springer-Verlag Berlin Heidelberg.

Brida D.,CNR Institute for Photonics and Nanotechnologies | Tomadin A.,CNR Institute of Neuroscience | Manzoni C.,CNR Institute for Photonics and Nanotechnologies | Kim Y.J.,University of Konstanz | And 7 more authors.
Nature Communications | Year: 2013

Graphene is emerging as a viable alternative to conventional optoelectronic, plasmonic and nanophotonic materials. The interaction of light with charge carriers creates an out-of-equilibrium distribution, which relaxes on an ultrafast timescale to a hot Fermi-Dirac distribution, that subsequently cools emitting phonons. Although the slower relaxation mechanisms have been extensively investigated, the initial stages still pose a challenge. Experimentally, they defy the resolution of most pump-probe setups, due to the extremely fast sub-100 fs carrier dynamics. Theoretically, massless Dirac fermions represent a novel many-body problem, fundamentally different from Schrödinger fermions. Here we combine pump-probe spectroscopy with a microscopic theory to investigate electron-electron interactions during the early stages of relaxation. We identify the mechanisms controlling the ultrafast dynamics, in particular the role of collinear scattering. This gives rise to Auger processes, including charge multiplication, which is key in photovoltage generation and photodetectors.© 2013 Macmillan Publishers Limited. All rights reserved.

Bobillo F.,University of Zaragoza | Straccia U.,CNR Institute of Neuroscience
IEEE International Conference on Fuzzy Systems | Year: 2011

Fuzzy Description Logics (Fuzzy DLs) are logics that allow to deal with structured knowledge affected by fuzziness. Fuzzy DLs are at the heart of Fuzzy OWL 2, a fuzzy version of the standard ontology language OWL 2. Although a relatively important amount of work has been carried out in the last years, fuzzy DLs are open to be extended with several features worked out in other fields. In particular, the integration of aggregation operators (AOs) in fuzzy DLs has received little attention so far. In this work, we show how to support aggregation operators in fuzzy DLs. We provide syntax and semantics of a fuzzy DL extended with AOs, and provide a calculus for a family of AOs (weighted sum, OWA and quantifier-guided OWA). We also show how to encode them into our proposal for Fuzzy OWL 2. © 2011 IEEE.

Polini M.,CNR Institute of Neuroscience | Guinea F.,CSIC - Institute of Materials Science | Lewenstein M.,ICFO - Institute of Photonic Sciences | Lewenstein M.,Catalan Institution for Research and Advanced Studies | And 4 more authors.
Nature Nanotechnology | Year: 2013

Artificial honeycomb lattices offer a tunable platform for studying massless Dirac quasiparticles and their topological and correlated phases. Here we review recent progress in the design and fabrication of such synthetic structures focusing on nanopatterning of two-dimensional electron gases in semiconductors, molecule-by-molecule assembly by scanning probe methods and optical trapping of ultracold atoms in crystals of light. We also discuss photonic crystals with Dirac cone dispersion and topologically protected edge states. We emphasize how the interplay between single-particle band-structure engineering and cooperative effects leads to spectacular manifestations in tunnelling and optical spectroscopies. © 2013 Macmillan Publishers Limited.

Bobillo F.,University of Zaragoza | Straccia U.,CNR Institute of Neuroscience
Applied Soft Computing Journal | Year: 2013

Fuzzy ontologies extend classical ontologies to allow the representation of imprecise and vague knowledge. Although a relatively important amount of work has been carried out in the field during the last years and they have been successfully used in several applications, several notions from fuzzy logic have not been considered yet in fuzzy ontologies. Among them are aggregation operators, mathematical functions used to fuse different pieces of information, which is a very common need. Some examples of aggregation operators are weighted sums, Ordered Weighting Averaging operators and fuzzy integrals. In this work, we integrate fuzzy ontologies and aggregation operators. As a theoretical formalism, we provide the syntax and semantics of a fuzzy Description Logic with fuzzy aggregation operators. We provide a reasoning algorithm for the family of operators that are representable using a Mixed Integer Linear Programming optimization problem. We also show how to encode some examples of aggregation operators using the language Fuzzy OWL 2. © 2013 Elsevier B.V. All rights reserved.

Giovannetti V.,CNR Institute of Neuroscience | Holevo A.S.,National Research University Higher School of Economics | Garcia-Patron R.,Free University of Colombia | Garcia-Patron R.,Max Planck Institute of Quantum Optics
Communications in Mathematical Physics | Year: 2014

The long-standing conjectures of the optimality of Gaussian inputs and additivity are solved for a broad class of gauge-covariant or contravariant bosonic Gaussian channels (which includes in particular thermal, additive classical noise, and amplifier channels) restricting to the class of states with finite second moments. We show that the vacuum is the input state which minimizes the entropy at the output of such channels. This allows us to show also that the classical capacity of these channels (under the input energy constraint) is additive and is achieved by Gaussian encodings. © 2014, Springer-Verlag Berlin Heidelberg.

Guerra R.,CNR Institute of Neuroscience | Tartaglino U.,International School for Advanced Studies | Vanossi A.,CNR Institute of Neuroscience | Vanossi A.,International School for Advanced Studies | And 2 more authors.
Nature Materials | Year: 2010

Sliding parts in nanosystems such as nanoelectromechanical systems and nanomotors1-9 increasingly involve large speeds, and rotations as well as translations of the moving surfaces; yet, the physics of high-speed nanoscale friction is so far unexplored. Here, by simulating the motion of drifting and of kicked Au clusters on graphite-a workhorse system of experimental relevance10-13-we demonstrate and characterize a new 'ballistic' friction regime at high speed, separate from drift at low speed. The temperature dependence of the cluster slip distance and time, measuring friction, is opposite in these two regimes, consistent with theory. Crucial to both regimes is the interplay of rotations and translations, shown to be correlated in slow drift but anticorrelated in fast sliding. Despite these differences, we find the velocity dependence of ballistic friction to be, like drift, viscous. © 2010 Macmillan Publishers Limited. All rights reserved.

Onorato M.,University of Turin | Onorato M.,National Institute of Nuclear Physics, Italy | Residori S.,University of Nice Sophia Antipolis | Bortolozzo U.,University of Nice Sophia Antipolis | And 3 more authors.
Physics Reports | Year: 2013

Rogue waves is the name given by oceanographers to isolated large amplitude waves, that occur more frequently than expected for normal, Gaussian distributed, statistical events. Rogue waves are ubiquitous in nature and appear in a variety of different contexts. Besides water waves, they have been recently reported in liquid Helium, in nonlinear optics, microwave cavities, etc. The first part of the review is dedicated to rogue waves in the oceans and to their laboratory counterpart with experiments performed in water basins. Most of the work and interpretation of the experimental results will be based on the nonlinear Schrödinger equation, an universal model, that rules the dynamics of weakly nonlinear, narrow band surface gravity waves. Then, we present examples of rogue waves occurring in different physical contexts and we discuss the related anomalous statistics of the wave amplitude, which deviates from the Gaussian behavior that were expected for random waves. The third part of the review is dedicated to optical rogue waves, with examples taken from the supercontinuum generation in photonic crystal fibers, laser fiber systems and two-dimensional spatiotemporal systems. In particular, the extreme waves observed in a two-dimensional spatially extended optical cavity allow us to introduce a description based on two essential conditions for the generation of rogue waves: nonlinear coupling and nonlocal coupling. The first requirement is needed in order to introduce an elementary size, such as that of the solitons or breathers, whereas the second requirement implies inhomogeneity, a mechanism needed to produce the events of mutual collisions and mutual amplification between the elementary solitons or wavepackets. The concepts of "granularity" and "inhomogeneity" as joint generators of optical rogue waves are introduced on the basis of a linear experiment. By extending these concepts to other systems, rogue waves can be classified as phenomena occurring in the presence of many uncorrelated "grains" of activity inhomogeneously distributed in large spatial domains, the "grains" being of linear or nonlinear origin, as in the case of wavepackets or solitons. © 2013 Elsevier B.V.

Pecker S.,Weizmann Institute of Science | Kuemmeth F.,Copenhagen University | Secchi A.,CNR Institute of Neuroscience | Secchi A.,University of Modena and Reggio Emilia | And 4 more authors.
Nature Physics | Year: 2013

Two electrons on a string form a simple model system where Coulomb interactions are expected to play an interesting role. In the presence of strong interactions, these electrons are predicted to form a Wigner molecule, separating to the ends of the string. This spatial structure is believed to be clearly imprinted on the energy spectrum, yet so far a direct measurement of such a spectrum in a controllable one-dimensional setting is still missing. Here we use an ultraclean carbon nanotube to realize this system in a tunable potential. Using tunnelling spectroscopy we measure the addition spectra of two interacting carriers, electrons or holes, and identify seven low-energy states characterized by their exchange symmetries. The formation of a Wigner molecule is evident from a tenfold quenching of the fundamental excitation energy as compared with the non-interacting value. Our ability to tune the two-carrier state in space and to study it for both electrons and holes provides an unambiguous demonstration of this strongly interacting quantum ground state. © 2013 Macmillan Publishers Limited.

Pronschinske A.,North Carolina State University | Chen Y.,North Carolina State University | Lewis G.F.,North Carolina State University | Shultz D.A.,North Carolina State University | And 5 more authors.
Nano Letters | Year: 2013

Scanning tunneling microscopy and local conductance mapping show spin-state coexistence in bilayer films of Fe[(H2Bpz2) 2bpy] on Au(111) that is independent of temperature between 131 and 300 K. This modification of bulk behavior is attributed in part to the unique packing constraints of the bilayer film that promote deviations from bulk behavior. The local density of states measured for different spin states shows that high-spin molecules have a smaller transport gap than low-spin molecules and are in agreement with density functional theory calculations. © 2013 American Chemical Society.

Schaefer M.,German Cancer Research Center | Pollex T.,German Cancer Research Center | Hanna K.,German Cancer Research Center | Tuorto F.,German Cancer Research Center | And 6 more authors.
Genes and Development | Year: 2010

Dnmt2 proteins are the most conserved members of the DNA methyltransferase enzyme family, but their substrate specificity and biological functions have been a subject of controversy. We show here that, in addition to tRNA Asp-GTC, tRNAVal-AAC and tRNAGly-GCC are also methylated by Dnmt2. Drosophila Dnmt2 mutants showed reduced viability under stress conditions, and Dnmt2 relocalized to stress granules following heat shock. Strikingly, stress-induced cleavage of tRNAs was Dnmt2-dependent, and Dnmt2-mediated methylation protected tRNAs against ribonuclease cleavage. These results uncover a novel biological function of Dnmt2-mediated tRNA methylation, and suggest a role for Dnmt2 enzymes during the biogenesis of tRNA-derived small RNAs. © 2010 by Cold Spring Harbor Laboratory Press.

Lorusso G.,University of Zaragoza | Sharples J.W.,University of Manchester | Palacios E.,University of Zaragoza | Roubeau O.,University of Zaragoza | And 7 more authors.
Advanced Materials | Year: 2013

The three-dimensional metal-organic framework Gd(HCOO)3 is characterized by a relatively compact crystal lattice of weakly interacting Gd3+ spin centers interconnected via lightweight formate ligands, overall providing a remarkably large magnetic:non-magnetic elemental weight ratio. The resulting magnetocaloric effect per unit volume is decidedly superior in Gd(HCOO)3 than in the best known magnetic refrigerant materials for liquid-helium temperatures and low-moderate applied fields. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Tomadin A.,CNR Institute of Neuroscience | Brida D.,University of Konstanz | Brida D.,CNR Institute for Photonics and Nanotechnologies | Cerullo G.,CNR Institute for Photonics and Nanotechnologies | And 2 more authors.
Physical Review B - Condensed Matter and Materials Physics | Year: 2013

We present a combined analytical and numerical study of the early stages (sub-100-fs) of the nonequilibrium dynamics of photoexcited electrons in graphene. We employ the semiclassical Boltzmann equation with a collision integral that includes contributions from electron-electron (e-e) and electron-optical phonon interactions. Taking advantage of circular symmetry and employing the massless Dirac fermion (MDF) Hamiltonian, we are able to perform an essentially analytical study of the e-e contribution to the collision integral. This allows us to take particular care of subtle collinear scattering processes - processes in which incoming and outgoing momenta of the scattering particles lie on the same line - including carrier multiplication (CM) and Auger recombination (AR). These processes have a vanishing phase space for two-dimensional MDF bare bands. However, we argue that electron-lifetime effects, seen in experiments based on angle-resolved photoemission spectroscopy, provide a natural pathway to regularize this pathology, yielding a finite contribution due to CM and AR to the Coulomb collision integral. Finally, we discuss in detail the role of physics beyond the Fermi golden rule by including screening in the matrix element of the Coulomb interaction at the level of the random phase approximation (RPA), focusing in particular on the consequences of various approximations including static RPA screening, which maximizes the impact of CM and AR processes, and dynamical RPA screening, which completely suppresses them. © 2013 American Physical Society.

D'Ambrosio V.,University of Rome La Sapienza | Nagali E.,University of Rome La Sapienza | Walborn S.P.,Federal University of Rio de Janeiro | Aolita L.,ICFO - Institute of Photonic Sciences | And 4 more authors.
Nature Communications | Year: 2012

Quantum communication employs the counter-intuitive features of quantum physics for tasks that are impossible in the classical world. It is crucial for testing the foundations of quantum theory and promises to revolutionize information and communication technologies. However, to execute even the simplest quantum transmission, one must establish, and maintain, a shared reference frame. This introduces a considerable overhead in resources, particularly if the parties are in motion or rotating relative to each other. Here we experimentally show how to circumvent this problem with the transmission of quantum information encoded in rotationally invariant states of single photons. By developing a complete toolbox for the efficient encoding and decoding of quantum information in such photonic qubits, we demonstrate the feasibility of alignment-free quantum key-distribution, and perform proof-of-principle demonstrations of alignment-free entanglement distribution and Bell-inequality violation. The scheme should find applications in fundamental tests of quantum mechanics and satellite-based quantum communication. © 2012 Macmillan Publishers Limited. All rights reserved.

Vitiello M.S.,CNR Institute of Neuroscience | Scalari G.,ETH Zurich | Williams B.,University of California at Los Angeles | De Natale P.,CNR Institute of Neuroscience | De Natale P.,Lens Inc
Optics Express | Year: 2015

We review the most recent technological and application advances of quantum cascade lasers, underlining the present milestones and future directions from the Mid-infrared to the Terahertz spectral range. Challenges and developments, which are the subject of the contributions to this focus issue, are also introduced. ©2015 Optical Society of America.

Ferrari A.,CNR Institute of Neuroscience | Cecchini M.,CNR Institute of Neuroscience | Dhawan A.,Cornell University | Micera S.,ETH Zurich | And 4 more authors.
Nano Letters | Year: 2011

We employ simple geometrical rules to design a set of nanotopographies able to interfere with focal adhesion establishment during neuronal differentiation. Exploiting nanoimprint lithography techniques on cyclic-olefin-copolymer films, we demonstrate that by varying a single topographical parameter the orientation and maturation of focal adhesions can be finely modulated yielding independent control over the final number and the outgrowth direction of neurites. Taken together, this report provides a novel and promising approach to the rational design of biocompatible textured substrates for tissue engineering applications. © 2011 American Chemical Society.

Agency: European Commission | Branch: FP7 | Program: CSA-SA | Phase: FP7-2008-PEOPLE-NIGHT | Award Amount: 85.96K | Year: 2008

2009 will be the world year of Astronomy with a special dedication to Galileo to celebrate the astronomic discoveries of Galileo Galilei. We decided to anticipate this event in our researchers night focusing it on the astronomy field. For this reason the main partners will be INAF (National Institute for Astrophysics) Capodimonte Observatory, without excluding our traditional partners Vesuvian Observatory, INOA and San Pietro a Majella Conservatory. The activities will set in Piazza Dante and in the beautiful cloister and auditorium of Conservatory, to guarantee the necessary in-door and out- door spaces. Piazza Dante will host the researchers stands, aimed to show the researchers activities, interactive experiments, videos, instruments and to talk and make acquaintance with researchers; a portable planetarium, the running music of Contrabbanda and the children dedicated shows of Le Nuvole (see their web site at www.lenuvole.com ): their stars related street-art performances with jugglers playing as researchers and a piece on Galileos life. A digital photographic challenge: shot the researchers night, open to researchers and public, will also take place between 18,00 and 21,00 and the winner of both categories will be awarded with a diploma and a dinner for four people. As contraposition to the planetarium a special area will host a simulation of heartquakes. A chorus of researchers leaded by maestro Lo Gatto and his wife Donatella (researcher in chemistry) will re-interpret ancient villanelle of Galileos time with modern rhythms of jazz, rock pop music. The cloister of Conservatorio will host the photographic exhibition portrait of a researcher with an extra section for Italian Flickr bloggers (Flickr is the most famous photo-blog, to have an idea see www.flickr.com ) while the awarding ceremony will be held in the auditorium followed by a performance of videos on Galileos discoveries and music composed by students of Music Apllied to Multimedia corse.

Agency: European Commission | Branch: FP7 | Program: CSA-SA | Phase: PEOPLE-2007-5-1.NIGHT | Award Amount: 79.67K | Year: 2007

Last year Dicocom organized the Neapolitan researchers night in the ancient centre of Naples,with the VEGAN project.This year we want to follow the same approach to give continuity to the event, also because weld like that the researchers night turn into a fix appointment for Naples, for this reason we decided to focus our project on the research between the past and the future and propose the same location:piazza Dante.Our project is based on the binomial research in the past/research for the future,we have from one side all the disciplines linked to archaeology,conservation and promotion of cultural heritage and the re-proposal of last year simulated excavation for children. In this context we intend to twin the event with others in the domain of cultural heritage: the exhibition realised in the frame of a Culture2000project and the launch of the ancient monastic complex of Cimitile.The other side is represented by scientific research focused on the future, in this context we tried to collect all the main Campanian research centres, from Universities to the CRC to the CNR to the National Astrophysics Institute to the association women in researchorganised.Moreover we will organise the Competition Draw a Researcher with an exhibition that will be held in the Monastic Citadel of Suor Orsola Benincasa University and another in the monastic complex of Cimitile.The main objective of this researchers night is to realise an event focused on the discovery,the fun and stay all together,with the maximum of participation to give to Neapolitan researchers the occasion to go in piazza and celebrate!Our aim is that researchers have an occasion to play with their knowledge involving people, to talk and dialogue with them to share their passion, that the researchers could demonstrate to everybody throughout scientific, amusing and divulgation activities that the research work doesnt alienate, doesnt isolate doesnt get people like laboratory rats,at the contrary

Hubener R.,Free University of Berlin | Mari A.,Free University of Berlin | Mari A.,University of Potsdam | Mari A.,CNR Institute of Neuroscience | Eisert J.,Free University of Berlin
Physical Review Letters | Year: 2013

Matrix product states and their continuous analogues are variational classes of states that capture quantum many-body systems or quantum fields with low entanglement; they are at the basis of the density-matrix renormalization group method and continuous variants thereof. In this work we show that, generically, N-point functions of arbitrary operators in discrete and continuous translation invariant matrix product states are completely characterized by the corresponding two- and three-point functions. Aside from having important consequences for the structure of correlations in quantum states with low entanglement, this result provides a new way of reconstructing unknown states from correlation measurements, e.g., for one-dimensional continuous systems of cold atoms. We argue that such a relation of correlation functions may help in devising perturbative approaches to interacting theories. © 2013 American Physical Society.

De Palma G.,CNR Institute of Neuroscience | De Palma G.,National Institute of Nuclear Physics, Italy | Mari A.,CNR Institute of Neuroscience | Giovannetti V.,CNR Institute of Neuroscience
Nature Photonics | Year: 2014

In most communication schemes, information is transmitted via travelling modes of electromagnetic radiation. These modes are unavoidably subject to environmental noise along any physical transmission medium, and the quality of the communication channel strongly depends on the minimum noise achievable at the output. For classical signals, such noise can be rigorously quantified in terms of the associated Shannon entropy and it is subject to a fundamental lower bound called the entropy power inequality. However, electromagnetic fields are quantum mechanical systems, so the quantum nature of the information carrier cannot be neglected - especially in low-intensity signals - and many important results derived within classical information theory require non-trivial extensions to the quantum regime. Here, we prove one possible generalization of the entropy power inequality to quantum bosonic systems. The impact of this inequality in quantum information theory is potentially large and some relevant implications are considered in this work. © 2014 Macmillan Publishers Limited. All rights reserved.

McPartland J.M.,GW Pharmaceuticals | McPartland J.M.,University of Vermont | Guy G.W.,GW Pharmaceuticals | Di Marzo V.,CNR Institute of Neuroscience
PLoS ONE | Year: 2014

Background: The "classic" endocannabinoid (eCB) system includes the cannabinoid receptors CB1 and CB2, the eCB ligands anandamide (AEA) and 2-arachidonoylglycerol (2-AG), and their metabolic enzymes. An emerging literature documents the "eCB deficiency syndrome" as an etiology in migraine, fibromyalgia, irritable bowel syndrome, psychological disorders, and other conditions. We performed a systematic review of clinical interventions that enhance the eCB system - ways to upregulate cannabinoid receptors, increase ligand synthesis, or inhibit ligand degradation. Methodology/Principal Findings: We searched PubMed for clinical trials, observational studies, and preclinical research. Data synthesis was qualitative. Exclusion criteria limited the results to 184 in vitro studies, 102 in vivo animal studies, and 36 human studies. Evidence indicates that several classes of pharmaceuticals upregulate the eCB system, including analgesics (acetaminophen, non-steroidal anti-inflammatory drugs, opioids, glucocorticoids), antidepressants, antipsychotics, anxiolytics, and anticonvulsants. Clinical interventions characterized as "complementary and alternative medicine" also upregulate the eCB system: massage and manipulation, acupuncture, dietary supplements, and herbal medicines. Lifestyle modification (diet, weight control, exercise, and the use of psychoactive substances - alcohol, tobacco, coffee, cannabis) also modulate the eCB system. Conclusions/Significance: Few clinical trials have assessed interventions that upregulate the eCB system. Many preclinical studies point to other potential approaches; human trials are needed to explore these promising interventions. © 2014 McPartland et al.

Leanza L.,University of Padua | Leanza L.,CNR Institute of Neuroscience | Leanza L.,University of Duisburg - Essen
Oncogene | Year: 2014

Mitochondria, the key bioenergetic intracellular organelles, harbor a number of proteins with proven or hypothetical ion channel functions. Growing evidence points to the important contribution of these channels to the regulation of mitochondrial function, such as ion homeostasis imbalances profoundly affecting energy transducing processes, reactive oxygen species production and mitochondrial integrity. Given the central role of mitochondria in apoptosis, their ion channels with the potential to compromise mitochondrial function have become promising targets for the treatment of malignancies. Importantly, in vivo evidence demonstrates the involvement of the proton-transporting uncoupling protein, a mitochondrial potassium channel, the outer membrane located porin and the permeability transition pore in tumor progression/control. In this review, we focus on mitochondrial channels that have been assigned a definite role in cell death regulation and possess clear oncological relevance. Overall, based on in vivo and in vitro genetic and pharmacological evidence, mitochondrial ion channels are emerging as promising targets for cancer treatment.

Dutta D.,University of Florida | Calvani R.,Catholic University of the Sacred Heart | Calvani R.,CNR Institute of Neuroscience | Bernabei R.,Catholic University of the Sacred Heart | And 3 more authors.
Circulation Research | Year: 2012

The prevalence of cardiovascular disease increases with advancing age. Although long-term exposure to cardiovascular risk factors plays a major role in the etiopathogenesis of cardiovascular disease, intrinsic cardiac aging enhances the susceptibility to developing heart pathologies in late life. The progressive decline of cardiomyocyte mitochondrial function is considered a major mechanism underlying heart senescence. Damaged mitochondria not only produce less ATP but also generate increased amounts of reactive oxygen species and display a greater propensity to trigger apoptosis. Given the postmitotic nature of cardiomyocytes, the efficient removal of dysfunctional mitochondria is critical for the maintenance of cell homeostasis, because damaged organelles cannot be diluted by cell proliferation. The only known mechanism whereby mitochondria are turned over is through macroautophagy. The efficiency of this process declines with advancing age, which may play a critical role in heart senescence and age-related cardiovascular disease. The present review illustrates the putative mechanisms whereby alterations in the autophagic removal of damaged mitochondria intervene in the process of cardiac aging and in the pathogenesis of specific heart diseases that are especially prevalent in late life (eg, left ventricular hypertrophy, ischemic heart disease, heart failure, and diabetic cardiomyopathy). Interventions proposed to counteract cardiac aging through improvements in macroautophagy (eg, calorie restriction and calorie restriction mimetics) are also presented. © 2012 American Heart Association, Inc.

Szabo I.,University of Padua | Leanza L.,University of Padua | Gulbins E.,University of Duisburg - Essen | Zoratti M.,University of Padua | Zoratti M.,CNR Institute of Neuroscience
Pflugers Archiv European Journal of Physiology | Year: 2012

The inner membrane of the ATP-producing organelles of endosymbiotic origin, mitochondria, has long been considered to be poorly permeable to cations and anions, since the strict control of inner mitochondrial membrane permeability is crucial for efficient ATP synthesis. Over the past 30 years, however, it has become clear that various ion channels-along with antiporters and uniporters-are present in the mitochondrial inner membrane, although at rather low abundance. These channels are important for energy supply, and some are a decisive factor in determining whether a cell lives or dies. Their electrophysiological and pharmacological characterisations have contributed importantly to the ongoing elucidation of their pathophysiological roles. This review gives an overview of recent advances in our understanding of the functions of the mitochondrial potassium channels identified so far. Open issues concerning the possible molecular entities giving rise to the observed activities and channel protein targeting to mitochondria are also discussed. © 2011 Springer-Verlag.

Bini D.,CNR Institute of Neuroscience | Bini D.,University of Rome La Sapienza | Bini D.,National Institute of Nuclear Physics, Italy | Geralico A.,University of Rome La Sapienza
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

The dynamics of extended bodies endowed with multipolar structure up to the mass quadrupole moment is investigated in the Schwarzschild background according to Dixon's model, extending previous works. The whole set of evolution equations is numerically integrated under the simplifying assumptions of constant frame components of the quadrupole tensor and that the motion of the center of mass be confined on the equatorial plane, the spin vector being orthogonal to it. The equations of motion are also solved analytically in the limit of small values of the characteristic length scales associated with the spin and quadrupole with respect to the background curvature characteristic length. The results are qualitatively and quantitatively different from previous analyses involving only spin structures. In particular, the presence of the quadrupole turns out to be responsible for the onset of a nonzero spin angular momentum, even if initially absent. © 2013 American Physical Society.

Rasola A.,CNR Institute of Neuroscience | Rasola A.,University of Padua | Neckers L.,Urologic | Picard D.,University of Geneva
Trends in Cell Biology | Year: 2014

Many tumors undergo a dramatic metabolic shift known as the Warburg effect in which glucose utilization is favored and oxidative phosphorylation is downregulated, even when oxygen availability is plentiful. However, the mechanistic basis for this switch has remained unclear. Recently several independent groups identified tumor necrosis factor receptor-associated protein 1 (TRAP1), a mitochondrial molecular chaperone of the heat shock protein 90 (Hsp90) family, as a key modulator of mitochondrial respiration. Although all reports agree that this activity of TRAP1 has important implications for neoplastic progression, data from the different groups only partially overlap, suggesting that TRAP1 may have complex and possibly contextual effects on tumorigenesis. In this review we analyze these recent findings and attempt to reconcile these observations. © 2014 Elsevier Ltd.

Wohlgemuth S.E.,University of Florida | Calvani R.,CNR Institute of Neuroscience | Marzetti E.,Catholic University of the Sacred Heart
Journal of Molecular and Cellular Cardiology | Year: 2014

Aging is accompanied by a progressive increase in the incidence and prevalence of cardiovascular disease (CVD). Prolonged exposure to cardiovascular risk factors, together with intrinsic age-dependent declines in cardiac functionality, increases the vulnerability of the heart to both endogenous and exogenous stressors, ultimately enhancing the susceptibility to developing CVD in late life. Both increased levels of oxidative damage and the accumulation of dysfunctional mitochondria have been observed in a wide range of cardiac diseases, which may therefore represent a common ground upon which many aspects of CVD develop. In this review, we summarize the current knowledge on the mechanisms whereby oxidative stress arising from mitochondrial dysfunction is involved in the process of cardiac aging and in the pathogenesis of CVD highly prevalent in late life (e.g., heart failure and ischemic heart disease). Special emphasis is placed on recent evidence about the role played by alterations in cellular quality control systems, in particular autophagy/mitophagy and mitochondrial dynamics (fusion and fission), and their interconnections in the context of age-related CVD. Cardioprotective interventions acting through the modulation of mitochondrial autophagy (calorie restriction, calorie restriction mimetics, and the gasotransmitter hydrogen sulfide) are also presented. This article is part of a Special Issue entitled "Protein Quality Control, the Ubiquitin Proteasome System, and Autophagy". © 2014 Elsevier Ltd.

Bagarello F.,University of Palermo | Bagarello F.,National Institute of Nuclear Physics, Italy | Gargano F.,CNR Institute of Neuroscience
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2014

We discuss the role of pseudofermions in the analysis of some two-dimensional models, recently introduced in connection with non-self-adjoint Hamiltonians. Among other aspects, we discuss the appearance of exceptional points in connection with the validity of the extended anticommutation rules which define the pseudofermionic structure. © 2014 American Physical Society.

Catuogno S.,CNR Institute of Neuroscience | Catuogno S.,University of Naples Federico II | Cerchia L.,CNR Institute of Neuroscience | Romano G.,IRCCS Fondazione SDN | And 4 more authors.
Oncogene | Year: 2013

MicroRNAs (miRNAs) constitute a class of small non-coding RNAs that negatively regulate the expression of their target genes. They are involved in many biological processes, including cell proliferation, apoptosis and differentiation, and are considered as promising new therapeutic targets for cancer. However, the identity of miRNAs involved in apoptosis and their respective targets remain largely unknown. Given the elevated complexity of miRNA regulation of gene expression, we performed a functional screening as an alternative strategy to identify those miRNAs that in lung cancer cells may interfere with the apoptotic process. To this aim, we generated a derivative of the non-small cell lung carcinoma A549 cell line in which caspase-8, a critical upstream initiator of apoptosis, can be activated by administration of the small dimerizer drug AP20187. We found a number of miRNAs that may rescue cell viability from caspase-8 activation. They included miRNAs already described as oncogenic such as miR-17, miR-135 and miR-520, but also some miRNAs such as miR-124-1 and miR-34c for which a tumor-suppressive role has instead been described or expected. Among them, miR-34c-5p markedly increased resistance to paclitaxel-induced apoptosis. We demonstrate that Bmf (Bcl-2-modifying factor) is a target of miR-34c-5p, and that its silencing, together with that of c-myc, a known target of miR-34c-5p, contributes to resistance to apoptosis induced by paclitaxel through p53 downregulation. © 2013 Macmillan Publishers Limited All rights reserved.

Amico L.,CNR Institute for Microelectronics and Microsystems | Rossini D.,CNR Institute of Neuroscience | Hamma A.,Perimeter Institute for Theoretical Physics | Korepin V.E.,State University of New York at Stony Brook
Physical Review Letters | Year: 2012

Information and correlations in a quantum system are closely related through the process of measurement. We explore such relation in a many-body quantum setting, effectively bridging between quantum metrology and condensed matter physics. To this aim we adopt the information-theory view of correlations and study the amount of correlations after certain classes of positive-operator-valued measurements are locally performed. As many-body systems, we consider a one-dimensional array of interacting two-level systems (a spin chain) at zero temperature, where quantum effects are most pronounced. We demonstrate how the optimal strategy to extract the correlations depends on the quantum phase through a subtle interplay between local interactions and coherence. © 2012 American Physical Society.

Hong J.,Rutgers University | Stroppa A.,CNR Institute of Neuroscience | Aniguez J.,CSIC - Institute of Materials Science | Picozzi S.,CNR Institute of Neuroscience | Vanderbilt D.,Rutgers University
Physical Review B - Condensed Matter and Materials Physics | Year: 2012

Spin-phonon coupling effects, as reflected in phonon frequency shifts between ferromagnetic (FM) and G-type antiferromagnetic (AFM) configurations in cubic CaMnO 3, SrMnO 3, BaMnO 3, LaCrO 3, LaFeO 3, and La 2(CrFe)O 6, are investigated using density-functional methods. The calculations are carried out both with a hybrid-functional Heyd-Scuseria-Ernzerhof (HSE) approach and with a DFT+ U approach using a U that has been fitted to HSE calculations. The phonon frequency shifts obtained in going from the FM to the AFM spin configuration agree well with those computed directly from the more accurate HSE approach, but are obtained with much less computational effort. We find that in the AMnO 3 materials class with A= Ca, Sr, and Ba, this frequency shift decreases as the A cation radius increases for the Γ phonons, while it increases for R-point phonons. In LaMO 3 with M= Cr, Fe, and Cr/Fe, the phonon frequencies at Γ decrease as the spin order changes from AFM to FM for LaCrO 3 and LaFeO 3, but they increase for the double perovskite La 2(CrFe)O 6. We discuss these results and the prospects for bulk and superlattice forms of these materials to be useful as multiferroics. © 2012 American Physical Society.

Giacomello M.,CNR Institute of Neuroscience | Drago I.,CNR Institute of Neuroscience | Bortolozzi M.,Venetian Institute of Molecular Medicine | Scorzeto M.,University of Padua | And 4 more authors.
Molecular Cell | Year: 2010

Although it is widely accepted that mitochondria in living cells can efficiently uptake Ca2+ during stimulation because of their vicinity to microdomains of high [Ca2+], the direct proof of Ca2+ hot spots' existence is still lacking. Thanks to a GFP-based Ca2+ probe localized on the cytosolic surface of the outer mitochondrial membrane, we demonstrate that, upon Ca2+ mobilization, the [Ca2+] in small regions of the mitochondrial surface reaches levels 5- to 10-fold higher than in the bulk cytosol. We also show that the [Ca2+] to which mitochondria are exposed during capacitative Ca2+ influx is similar between near plasma membrane mitochondria and organelles deeply located in the cytoplasm, whereas it is 2- to 3-fold higher in subplasma membrane mitochondria upon activation of voltage-gated Ca2+ channels. These results demonstrate that mitochondria are exposed to Ca2+ hot spots close to the ER but are excluded from the regions where capacitative Ca2+ influx occurs. © 2010 Elsevier Inc. All rights reserved.

Leanza L.,University of Padua | Henry B.,University of Duisburg - Essen | Sassi N.,CNR Institute of Neuroscience | Zoratti M.,CNR Institute of Neuroscience | And 3 more authors.
EMBO Molecular Medicine | Year: 2012

Overcoming the resistance of tumours to chemotherapy, often due to downregulation of Bax and Bak, represents a significant clinical challenge. It is therefore important to identify novel apoptosis inducers that bypass Bax and Bak. Potassium channels are emerging as oncological targets and a crucial role of mitochondrial Kv1.3 in apoptosis has been demonstrated. Here we report for the first time that Psora-4, PAP-1 and clofazimine, three distinct membrane-permeant inhibitors of Kv1.3, induce death by directly targeting the mitochondrial channel in multiple human and mouse cancer cell lines. Importantly, these drugs activated the intrinsic apoptotic pathway also in the absence of Bax and Bak, a result in agreement with the current mechanistic model for mitochondrial Kv1.3 action. Genetic deficiency or short interfering RNA (siRNA)-mediated downregulation of Kv1.3 abrogated the effects of the drugs. Intraperitoneal injection of clofazimine reduced tumour size by 90% in an orthotopic melanoma B16F10 mouse model in vivo, while no adverse effects were observed in several healthy tissues. The study indicates that inhibition of mitochondrial Kv1.3 might be a novel therapeutic option for the induction of cancer cell death independent of Bax and Bak. © 2012 EMBO Molecular Medicine.

Gomes L.C.,Dulbecco Telethon Institute | Gomes L.C.,Venetian Institute of Molecular Medicine | Gomes L.C.,University of Coimbra | Benedetto G.D.,Venetian Institute of Molecular Medicine | And 4 more authors.
Nature Cell Biology | Year: 2011

A plethora of cellular processes, including apoptosis, depend on regulated changes in mitochondrial shape and ultrastructure. The role of mitochondria and of their morphology during autophagy, a bulk degradation and recycling process of eukaryotic cells constituents, is not well understood. Here we show that mitochondrial morphology determines the cellular response to macroautophagy. When autophagy is triggered, mitochondria elongate in vitro and in vivo. During starvation, cellular cyclic AMP levels increase and protein kinase A (PKA) is activated. PKA in turn phosphorylates the pro-fission dynamin-related protein 1 (DRP1), which is therefore retained in the cytoplasm, leading to unopposed mitochondrial fusion. Elongated mitochondria are spared from autophagic degradation, possess more cristae, increased levels of dimerization and activity of ATP synthase, and maintain ATP production. Conversely, when elongation is genetically or pharmacologically blocked, mitochondria consume ATP, precipitating starvation-induced death. Thus, regulated changes in mitochondrial morphology determine the fate of the cell during autophagy. © 2011 Macmillan Publishers Limited. All rights reserved.

Wu H.,University of Cologne | Wu H.,Fudan University | Stroppa A.,CNR Institute of Neuroscience | Sakong S.,University of Duisburg - Essen | And 3 more authors.
Physical Review Letters | Year: 2010

It is shown that substitution of C or N for O recently proposed as a way to create ferromagnetism in otherwise nonmagnetic oxide insulators is curtailed by formation of impurity pairs, and the resultant C2 spin=1 dimers as well as the isoelectronic N22+ interact antiferromagnetically in p-type MgO. For C-doped ZnO, however, we demonstrate using the Heyd-Scuseria-Ernzerhof hybrid functional that a resonance of the spin-polarized C2 ppπ* states with the host conduction band results in a long-range ferromagnetic interaction. Magnetism of open-shell impurity molecules is proposed as a possible route to d0-ferromagnetism in oxide spintronic materials. © 2010 The American Physical Society.

Cederholm T.,Uppsala University Hospital | Cruz-Jentoft A.J.,Uppsala University Hospital | Maggi S.,CNR Institute of Neuroscience
European Journal of Physical and Rehabilitation Medicine | Year: 2013

Sarcopenia, a reduction in muscle mass and muscle function, is considered one of the hallmarks of the aging process. Current views consider sarcopenia as the consequence of multiple medical, behavioural and environmental factors that characterize aged individuals. Likewise bone fragility is known to depend on several pathogenetic mechanisms leading to bone mass loss and reduction of bone strength. Muscle weakness, fear of falls, falls and subsequent fractures are associated to concurrent sarcopenia and osteoporosis and lead to restricted mobility, loss of autonomy and reduced life expectancy. The skeletal and the muscular organ systems are tightly intertwined: the strongest mechanical forces applied to bones are, indeed, those created by muscle contractions that condition bone density, strength, and microarchitecture. Not surprising, therefore, the decrease in muscle strength leads to lower bone strength. The degenerative processes leading to osteoporosis and sarcopenia show many common pathogenic pathways, like the sensitivity to reduced anabolic hormone secretion, increased inflammatory cytokine activity and reduced physical activity. Thus they may also respond to the same kind of treatments. Basic is life-style interventions related to exercise and nutrition. Sufficient vitamin D levels are of importance for both bone and muscle, primarily provided by sun exposure at younger age, and by supplementation at older age. Resistance training several times per week is crucial, and to be effective adequate access to energy and proteins is necessary.

Szabo I.,University of Padua | Zoratti M.,CNR Institute of Neuroscience | Gulbins E.,University of Duisburg - Essen
FEBS Letters | Year: 2010

Recent evidence points to the crucial involvement of voltage-gated potassium channels (Kv) in apoptotic volume decrease and in the regulation of apoptosis in several systems. We have recently described the presence of a Kv channel, Kv1.3, in the mitochondria of lymphocytes. Expression of the channel correlated with increased sensitivity to apoptotic stimuli. Mitochondrial Kv1.3 contributes to the apoptotic cascade in T lymphocytes by interacting with pro-apoptotic Bax resulting in alteration of mitochondrial functional parameters and ultimately, in cytochrome c release. The present review summarizes the current understanding of the function of Kv channels in apoptosis in several cell types as well as the role of mitochondrial Kv1.3 in the regulation of cell death in lymphocytes. © 2010 Federation of European Biochemical Societies.

Lezama I.G.,University of Geneva | Nakano M.,RIKEN | Minder N.A.,University of Geneva | Chen Z.,Polyera Corporation | And 6 more authors.
Nature Materials | Year: 2012

Organic semiconductors based on small conjugated molecules generally behave as insulators when undoped, but the heterointerfaces of two such materials can show electrical conductivity as large as in a metal. Although charge transfer is commonly invoked to explain the phenomenon, the details of the process and the nature of the interfacial charge carriers remain largely unexplored. Here we use Schottky-gated heterostructures to probe the conducting layer at the interface between rubrene and PDIF-CN 2 single crystals. Gate-modulated conductivity measurements demonstrate that interfacial transport is due to electrons, whose mobility exhibits band-like behaviour from room temperature to ∼150 K, and remains as high as ∼1 cm 2 V -1 s -1 at 30 K for the best devices. The electron density decreases linearly with decreasing temperature, an observation that can be explained quantitatively on the basis of the heterostructure band diagram. These results elucidate the electronic structure of rubrene/PDIF-CN 2 interfaces and show the potential of Schottky-gated organic heterostructures for the investigation of transport in molecular semiconductors. © 2012 Macmillan Publishers Limited. All rights reserved.

Mari A.,Free University of Berlin | Mari A.,University of Potsdam | Mari A.,CNR Institute of Neuroscience | Eisert J.,Free University of Berlin
Physical Review Letters | Year: 2012

We show that quantum circuits where the initial state and all the following quantum operations can be represented by positive Wigner functions can be classically efficiently simulated. This is true both for continuous-variable as well as discrete variable systems in odd prime dimensions, two cases which will be treated on entirely the same footing. Noting the fact that Clifford and Gaussian operations preserve the positivity of the Wigner function, our result generalizes the Gottesman-Knill theorem. Our algorithm provides a way of sampling from the output distribution of a computation or a simulation, including the efficient sampling from an approximate output distribution in the case of sampling imperfections for initial states, gates, or measurements. In this sense, this work highlights the role of the positive Wigner function as separating classically efficiently simulable systems from those that are potentially universal for quantum computing and simulation, and it emphasizes the role of negativity of the Wigner function as a computational resource. © 2012 American Physical Society.

Fillion-Gourdeau F.,University of Montréal | Herrmann H.J.,ETH Zurich | Mendoza M.,ETH Zurich | Palpacelli S.,Numidia Srl | Succi S.,CNR Institute of Neuroscience
Physical Review Letters | Year: 2013

We point out a formal analogy between the Dirac equation in Majorana form and the discrete-velocity version of the Boltzmann kinetic equation. By a systematic analysis based on the theory of operator splitting, this analogy is shown to turn into a concrete and efficient computational method, providing a unified treatment of relativistic and nonrelativistic quantum mechanics. This might have potentially far-reaching implications for both classical and quantum computing, because it shows that, by splitting time along the three spatial directions, quantum information (Dirac-Majorana wave function) propagates in space-time as a classical statistical process (Boltzmann distribution). © 2013 American Physical Society.

Arecchi F.T.,University of Florence | Arecchi F.T.,CNR Institute of Neuroscience | Bortolozzo U.,University of Nice Sophia Antipolis | Montina A.,Perimeter Institute for Theoretical Physics | Residori S.,University of Nice Sophia Antipolis
Physical Review Letters | Year: 2011

In the presence of many waves, giant events can occur with a probability higher than expected for random dynamics. By studying linear light propagation in a glass fiber, we show that optical rogue waves originate from two key ingredients: granularity, or a minimal size of the light speckles at the fiber exit, and inhomogeneity, that is, speckles clustering into separate domains with different average intensities. These two features characterize also rogue waves in nonlinear systems; thus, nonlinearity just plays the role of bringing forth the two ingredients of granularity and inhomogeneity. © 2011 American Physical Society.

Burr D.,University of Florence | Burr D.,CNR Institute of Neuroscience | Thompson P.,University of York
Vision Research | Year: 2011

This review traces progress made in the field of visual motion research from 1985 through to 2010. While it is certainly not exhaustive, it attempts to cover most of the major achievements during that period, and speculate on where the field is heading. © 2011 Elsevier Ltd.

Guo J.,University of Genoa | Emslie A.G.,Western Kentucky University | Massone A.M.,CNR Institute of Neuroscience | Piana M.,University of Genoa | Piana M.,CNR Institute of Neuroscience
Astrophysical Journal | Year: 2012

Using RHESSI hard X-ray imaging spectroscopy observations, we analyze electron flux maps for a number of extended coronal loop flares. For each event, we fit a collisional model with an extended acceleration region to the observed variation of loop length with electron energy E, resulting in estimates of the plasma density in, and longitudinal extent of, the acceleration region. These quantities in turn allow inference of the number of particles within the acceleration region and hence the filling factor f - the ratio of the emitting volume to the volume that encompasses the emitting region(s). We obtain values of f that lie mostly between 0.1 and 1.0; the (geometric) mean value is f = 0.20 ×/÷ 3.9, somewhat less than, but nevertheless consistent with, unity. Further, coupling information on the number of particles in the acceleration region with information on the total rate of acceleration of particles above a certain reference energy (obtained from spatially integrated hard X-ray data) also allows inference of the specific acceleration rate (electron s-1 per ambient electron above the chosen reference energy). We obtain a (geometric) mean value of the specific acceleration rate η(20 keV) =(6.0 ×/÷ 3.4) × 10-3 electrons s-1 per ambient electron; this value has implications both for the global electrodynamics associated with replenishment of the acceleration region and for the nature of the particle acceleration process. © 2012 The American Astronomical Society. All rights reserved.

Peotta S.,CNR Institute of Neuroscience | Rossini D.,CNR Institute of Neuroscience | Polini M.,Normal School of Pisa | Minardi F.,University of Florence | And 2 more authors.
Physical Review Letters | Year: 2013

By means of the time-dependent density-matrix renormalization-group (TDMRG) method we are able to follow the real-time dynamics of a single impurity embedded in a one-dimensional bath of interacting bosons. We focus on the impurity breathing mode, which is found to be well described by a single oscillation frequency and a damping rate. If the impurity is very weakly coupled to the bath, a Luttinger-liquid description is valid and the impurity suffers an Abraham-Lorentz radiation-reaction friction. For a large portion of the explored parameter space, the TDMRG results fall well beyond the Luttinger-liquid paradigm. © 2013 American Physical Society.

Rizza C.,University of Insubria | Rizza C.,CNR Institute of Neuroscience | Ciattoni A.,CNR Institute of Neuroscience
Physical Review Letters | Year: 2013

We show that in the presence of a rapidly modulated dielectric permittivity with a large modulation depth (Kapitza medium) a novel and robust regime of diffractionless electromagnetic propagation occurs. This happens when the mean value to depth ratio of the dielectric profile is comparable to the small ratio between the modulation period and the wavelength. We show that the standard effective medium theory is inadequate to describe the proposed regime and that its occurrence is not substantially hampered by medium losses. We check the feasibility of the proposed regime by means of a large modulation depth metal-dielectric layered medium whose electromagnetic behavior is analytically investigated. © 2013 American Physical Society.

Muniz-Miranda M.,University of Florence | Muniz-Miranda M.,European Laboratory for Nonlinear Spectroscopy LENS | Gellini C.,University of Florence | Gellini C.,European Laboratory for Nonlinear Spectroscopy LENS | Giorgetti E.,CNR Institute of Neuroscience
Journal of Physical Chemistry C | Year: 2011

Copper colloidal nanoparticles are obtained by laser ablation in aqueous solutions of ligands by nanosecond laser pulses at 532 and 1064 nm and examined by localized surface plasmon resonance (LSPR) and surface-enhanced Raman scattering (SERS) spectroscopy, along with transmission electron microscopy (TEM) and zeta potential measurements. This fabrication method, besides providing SERS-active substrates without spectral interferences of reagents, as it generally occurs for the chemical reduction of metal ions, allows obtaining colloidal suspensions which are stable in time because the copper particles are capped by ligand molecules as long as they are formed by laser ablation. This prevents aggregation among metal nanoparticles and probably reduces overall oxidation of the copper surface. © 2011 American Chemical Society.

Aquaro G.D.,CNR Institute of Neuroscience | Pingitore A.,CNR Institute of Neuroscience | Strata E.,University of Florence | Di Bella G.,Messina University | And 2 more authors.
Journal of the American College of Cardiology | Year: 2010

Objectives We investigated whether the presence of right ventricular (RV) abnormalities detected by cardiovascular magnetic resonance (CMR) predict adverse outcome in patients presenting with frequent premature ventricular complexes (PVCs) of left bundle branch block (LBBB) morphology. Background CMR is a component of the diagnostic workup for the differential diagnosis between arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) and idiopathic RV tachycardia. RV abnormalities evaluated by CMR could have prognostic importance. Methods Four hundred forty consecutive patients with >1,000 PVCs of LBBB morphology (minor diagnostic criterion of ARVC/D) and no other pre-existing criteria were prospectively enrolled. RV wall motion (WM), signal abnormalities, dilation, and reduced ejection fraction evaluated by CMR were considered imaging criteria of ARVC/D. Follow-up was performed evaluating an index composite end point of 3 cardiac events: cardiac death, resuscitated cardiac arrest, and appropriate implantable cardiac-defibrillator shock. Results Subjects with multiple RV abnormalities (RVA-2 group) had worse outcome than the no-RVA group (hazard ratio [HR]: 48.6; 95% confidence interval [CI]: 6.1 to 384.8; p < 0.001). Of the 61 patients in the RVA-2 group, only 6 had a definite diagnosis of ARVC/D applying the Task Force Criteria. Also, subjects with a single imaging criterion (RVA-1 group) had worse outcome than the no-RVA group (HR: 18.2; 95% CI: 2.0 to 162.6; p = 0.01). Patients with only WM abnormalities had higher prevalence of cardiac events than no-RVA (HR: 27.2; 95% CI: 3.0 to 244.0; p = 0.03). Conclusions In subjects with frequent PVC of LBBB morphology, CMR allows risk stratification. RV abnormalities were associated with worse outcome. © 2010 American College of Cardiology Foundation.

Minissale A.,CNR Institute of Neuroscience | Vaselli O.,CNR Institute of Neuroscience | Vaselli O.,University of Florence
Applied Geochemistry | Year: 2011

This paper describes an indirect method to calculate the isotopic composition of rainfall by using the isotopic composition of karst springs fed by waters circulating in the most important regional aquifer of central Italy, i.e. the Mesozoic limestone sequence that forms the backbone of the Apennines. By using δ 18O and δD data and the δ 18O (and/or δD) average gradient for elevation, evaluated through the use of literature rainfall data and new measurements from a typical Alpine valley in northern Italy, the altitude of precipitation of their parent water has been re-calculated. Vertical descents of more than 2000m, from recharge to discharge, have been assessed in some high flow-rate cold springs in the morphologically steep Adriatic sector of central Italy. A clear correlation between the vertical descents and more negative isotopic compositions at their relative emergence elevations is highlighted. In contrast, in the Tyrrhenian sector lower karstic drops (generally lower than 500m) correlate with less negative isotopic composition of recharge areas.The δ 18O iso-contour map of the " recalculated" parent rainfall in central Italy is more detailed than any possible isotopic map of rainfall made using pluviometers, unless large number of rainfall collectors were deployed on mountaintops. The data also show that the isotopic composition of rainfall depends on the source of the storm water. In particular, precipitation is isotopically heavier when originating in the Mediterranean Sea, and lighter when formed in the Atlantic Ocean. Consequently, the collision between air masses with such a different isotopic signature results in a relatively small latitudinal fractionation effect. The peninsular part of central Italy is very narrow, with several mountains and massifs more that 2000m high, and any latitudinal variation in the isotopic composition between rainfall sourced in the Atlantic Ocean and in the Mediterranean Sea is much lower than that due to the isotopic fractionation due to elevation. © 2011 Elsevier Ltd.

Mahler L.,CNR Institute of Neuroscience | Tredicucci A.,CNR Institute of Neuroscience | Beltram F.,CNR Institute of Neuroscience | Walther C.,ETH Zurich | And 4 more authors.
Nature Photonics | Year: 2010

Although lasers have found numerous applications, their design is often still based on the concept of a gain medium within a mirror cavity. Exceptions to this are distributed feedback lasers1, in which feedback develops along a periodic structure, or random lasers, which do not require any form of cavity2. Random lasers have very rich emission spectra, but are difficult to control. Distributed feedback devices, conversely, have the same limited design possibilities of regular lasers. We show, by making use of a quasi-crystalline structure in an electrically pumped device, that several advantages of a random laser can be combined with the predictability of a distributed feedback resonator. We have constructed a terahertz quantum cascade laser based on a Fibonacci distributed feedback sequence, and show that engineering of the self-similar spectrum of the grating allows features beyond those possible with traditional periodic resonators, such as directional output independent of the emission frequency and multicolour operation. © 2010 Macmillan Publishers Limited. All rights reserved.

Tognini P.,Normal School of Pisa | Tognini P.,CNR Institute of Neuroscience | Pizzorusso T.,CNR Institute of Neuroscience | Pizzorusso T.,University of Florence
International Journal of Biochemistry and Cell Biology | Year: 2012

MicroRNAs (miRNAs) are small non-coding RNAs that mediate post-transcriptional gene silencing. It is increasingly clear that miRNAs are key regulatory factors for a tight gene expression control. MiRNAs are involved in many aspects of organism development and function, in physiological and pathological conditions. MiRNA expression varies with cell type, tissue and developmental stages. The microRNA212/132 family is one of the most studied miRNA family due to the involvement of miR132 and miR212 in important cellular processes, especially in the brain. MiR132 and miR212 have been implicated in tissue development and in the formation and plasticity of neuronal connections. The main aim of this review is to highlight recent discoveries about miR212/132 family functions and its possible involvement in pathological processes. © 2011 Elsevier Ltd. All rights reserved.

Gherardini L.,CNR Institute of Neuroscience | Gennaro M.,CNR Institute of Neuroscience | Pizzorusso T.,CNR Institute of Neuroscience | Pizzorusso T.,University of Florence
Cerebral Cortex | Year: 2015

Ischemic stroke insults may lead to chronic functional limitations that adversely affect patient movements. Partial motor recovery is thought to be sustained by neuronal plasticity, particularly in areas close to the lesion site. It is still unknown if treatments acting exclusively on cortical plasticity of perilesional areas could result in behavioral amelioration. We tested whether enhancing plasticity in the ipsilesional cortex using local injections of chondroitinase ABC (ChABC) could promote recovery of skilled motor function in a focal cortical ischemia of forelimb motor cortex in rats. Using the skilled reaching test, we found that acute and delayed ChABC treatment induced recovery of impaired motor skills in treated rats. vGLUT1, vGLUT2, and vGAT staining indicated that functional recovery after acute ChABC treatment was associated with local plastic modification of the excitatory cortical circuitry positive for VGLUT2. ChABC effects on vGLUT2 staining were present only in rats undergoing behavioral training. Thus, the combination of treatments targeting the CSPG component of the extracellular matrix in perilesional areas and rehabilitation could be sufficient to enhance functional recovery from a focal stroke. © 2013 The Author.

Saladino R.,University of Tuscia | Botta G.,University of Tuscia | Pino S.,University of Rome La Sapienza | Costanzo G.,CNR Institute of Neuroscience | Di Mauro E.,University of Rome La Sapienza
Chemical Society Reviews | Year: 2012

Life is made of the intimate interaction of metabolism and genetics, both built around the chemistry of the most common elements of the Universe (hydrogen, oxygen, nitrogen, and carbon). The transmissible interaction of metabolic and genetic cycles results in the hypercycles of organization and de-organization of chemical information, of living and non-living. The origin-of-life quest has long been split into several attitudes exemplified by the aphorisms "genetics-first" or "metabolism-first". Recently, the opposition between these approaches has been solved by more unitary theoretical and experimental frames taking into account energetic, evolutionary, proto-metabolic and environmental aspects. Nevertheless, a unitary and simple chemical frame is still needed that could afford both the precursors of the synthetic pathways eventually leading to RNA and to the key components of the central metabolic cycles, possibly connected with the synthesis of fatty acids. In order to approach the problem of the origin of life it is therefore reasonable to start from the assumption that both metabolism and genetics had a common origin, shared a common chemical frame, and were embedded under physical-chemical conditions favourable for the onset of both. The singleness of such a prebiotically productive chemical process would partake of Darwinian advantages over more complex fragmentary chemical systems. The prebiotic chemistry of formamide affords in a single and simple physical-chemical frame nucleic bases, acyclonucleosides, nucleotides, biogenic carboxylic acids, sugars, amino sugars, amino acids and condensing agents. Thus, we suggest the possibility that formamide could have jointly provided the main components for the onset of both (pre)genetic and (pre)metabolic processes. As a note of caution, we discuss the fact that these observations only indicate possible solutions at the level of organic substrates, not at the systemic chemical level. © 2012 The Royal Society of Chemistry.

Nesterenko A.V.,Joint Institute for Nuclear Research | Simolo C.,CNR Institute of Neuroscience
Computer Physics Communications | Year: 2011

The QCDMAPT program package facilitates computations in the framework of dispersive approach to Quantum Chromodynamics. The QCDMAPT-F version of this package enables one to perform such computations with Fortran, whereas the previous version was developed for use with Maple system. The QCDMAPT-F package possesses the same basic features as its previous version. Namely, it embodies the calculated explicit expressions for relevant spectral functions up to the four-loop level and the subroutines for necessary integrals. New version program summary: Program title: QCDMAPT-F Catalogue identifier: AEGP-v2-0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AEGP-v2-0.html Program obtainable from: CPC Program Library, Queens University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 10 786 No. of bytes in distributed program, including test data, etc.: 332 329 Distribution format: tar.gz Programming language: Fortran 77 and higher Computer: Any which supports Fortran 77 Operating system: Any which supports Fortran 77 Classification: 11.1, 11.5, 11.6 External routines: MATHLIB routine RADAPT (D102) from CERNLIB Program Library [1] Catalogue identifier of previous version: AEGP-v1-0 Journal reference of previous version: Comput. Phys. Comm. 181 (2010) 1769 Does the new version supersede the previous version?: No. This version provides an alternative to the previous, Maple, version. Nature of problem: A central object of the dispersive (or "analytic") approach to Quantum Chromodynamics [2,3] is the so-called spectral function, which can be calculated by making use of the strong running coupling. At the one-loop level the latter has a quite simple form and the relevant spectral function can easily be calculated. However, at the higher loop levels the strong running coupling has a rather cumbersome structure. Here, the explicit calculation of corresponding spectral functions represents a somewhat complicated task (see Section 3 and Appendix B of Ref. [4]), whereas their numerical evaluation requires a lot of computational resources and essentially slows down the overall computation process. Solution method: The developed package includes the calculated explicit expressions for relevant spectral functions up to the four-loop level and the subroutines for necessary integrals. Reasons for new version: The previous version of the package (Ref. [4]) was developed for use with Maple system. The new version is developed for Fortran programming language. Summary of revisions: The QCDMAPT-F package consists of the main program (QCDMAPT-F.f) and two samples of the file containing the values of input parameters (QCDMAPT-F.i1 and QCDMAPT-F.i2). The main program includes the definitions of relevant spectral functions and subroutines for necessary integrals. The main program also provides an example of computation of the values of (M)APT spacelike/timelike expansion functions for the specified set of input parameters and (as an option) generates the output data files with values of these functions over the given kinematic intervals. Additional comments: For the proper functioning of QCDMAPT-F package, the "MATHLIB" CERNLIB library [1] has to be installed. Running time: The running time of the main program with sample set of input parameters specified in the file QCDMAPT-F.i2 is about a minute (depends on CPU). References: Subroutine D102 of the "MATHLIB" CERNLIB library, URL addresses: http://cernlib.web.cern.ch/ cernlib/mathlib.html, http://wwwasdoc.web.cern.ch/wwwasdoc/shortwrupsdir/d102/ top.html.D.V. Shirkov, I.L. Solovtsov, Phys. Rev. Lett. 79 (1997) 1209; K.A. Milton, I.L. Solovtsov, Phys. Rev. D 55 (1997) 5295;K.A. Milton, I.L. Solovtsov, Phys. Rev. D 59 (1999) 107701;I.L. Solovtsov, D.V. Shirkov, Theor. Math. Phys. 120 (1999) 1220;D.V. Shirkov, I.L. Solovtsov, Theor. Math. Phys. 150 (2007) 132.A.V. Nesterenko, Phys. Rev. D 62 (2000) 094028; A.V. Nesterenko, Phys. Rev. D 64 (2001) 116009;A.V. Nesterenko, Int. J. Mod. Phys. A 18 (2003) 5475;A.V. Nesterenko, J. Papavassiliou, J. Phys. G 32 (2006) 1025;A.V. Nesterenko, Nucl. Phys. B (Proc. Suppl.) 186 (2009) 207.A.V. Nesterenko, C. Simolo, Comput. Phys. Comm. 181 (2010) 1769. © 2011 Elsevier B.V. All rights reserved.

Poliseno L.,CNR Institute of Clinical Physiology | Poliseno L.,CNR Institute of Neuroscience | Pandolfi P.P.,Beth Israel Deaconess Medical Center
Methods | Year: 2015

In multiple human cancer types, a close link exists between the expression levels of Phosphatase and Tensin Homolog deleted on chromosome 10 (PTEN) and its oncosuppressive activities. Therefore, an in depth understanding of the molecular mechanisms by which PTEN expression is modulated is crucial in order to achieve a comprehensive knowledge of its biological roles. In recent years, the competition between PTEN mRNA and other RNAs for shared microRNA molecules has emerged as one such mechanism and has brought into focus the coding-independent activities of PTEN and other mRNAs. In this review article, we examine the competing endogenous RNA (ceRNA) partners of PTEN that have been identified so far. We also discuss how PTEN-centered ceRNA networks can contribute to a deeper understanding of PTEN function and tumorigenesis. © 2015.

Ravera F.,CNR Institute of Neuroscience | Loglio G.,University of Florence | Kovalchuk V.I.,NASU F. D. Ovcharenko Institute of Biocolloidal Chemistry
Current Opinion in Colloid and Interface Science | Year: 2010

Dilational rheology represents a powerful tool to investigate equilibrium and dynamic properties of simple and more complex interfacial layers containing surfactants, proteins, polymers or micro-nano sized particles. Concerning the experimental techniques for dilational rheology, drop/bubble tensiometers based on the acquisition of the drop/bubble profile and capillary pressure tensiometers are especially effective.This article focuses on oscillating drop/bubble methodologies where harmonic variations of the interfacial area are utilized for the measurement of the dilational viscoelasticity in the frequency domain. The increasing efficiency of these techniques of the last ten years is due, from one side, to the implementation of advanced instrumentations which make faster the drop/bubble control and the data acquisition and, on the other side, to the application of new theoretical approaches for data acquisition and interpretation.A critical analysis of such drop/bubble instruments is presented where their potentialities and limitations are underlined. Moreover, recent improvements in the definition of calculation methods based on the modelling of the experimental set up are reviewed together with some examples of experimental studies based on the utilisation of such methodologies. © 2010 Elsevier Ltd.

Ceriotti M.,ETH Zurich | Bussi G.,CNR Institute of Neuroscience | Parrinello M.,ETH Zurich
Journal of Chemical Theory and Computation | Year: 2010

Recently, we have shown how a colored-noise Langevin equation can be used in the context of molecular dynamics as a tool to obtain dynamical trajectories whose properties are tailored to display desired sampling features. In the present paper, after having reviewed some analytical results for the stochastic differential equations forming the basis of our approach, we describe in detail the implementation of the generalized Langevin equation thermostat and the fitting procedure used to obtain optimal parameters. We also discuss the simulation of nuclear quantum effects and demonstrate that by carefully choosing parameters one can successfully model strongly anharmonic solids such as neon. For the readers convenience, a library of thermostat parameters and some demonstrative code can be downloaded from an online repository. © 2010 American Chemical Society.

Rizza C.,University of Insubria | Rizza C.,CNR Institute of Neuroscience | Di Falco A.,University of St. Andrews | Ciattoni A.,CNR Institute of Neuroscience
Applied Physics Letters | Year: 2011

We have fabricated a nano-laminate by alternating metal and gain medium layers, the gain dielectric consisting of a polymer incorporating optically pumped dye molecules. From standard reflection-transmission experiments, we show that, at a visible wavelength, both the real and the imaginary parts of the permittivity attain very small values and we measure, at 604 nm, = 0. 04 which is 21.5 smaller than its value in the absence of optical pumping. Our investigation thus proves that a medium with a permittivity with very small modulus, a key condition promising efficient subwavelength optical steering, can be actually synthesized. © 2011 American Institute of Physics.

Deri L.,CNR Institute of Neuroscience | Fusco F.,ETH Zurich
2013 9th International Wireless Communications and Mobile Computing Conference, IWCMC 2013 | Year: 2013

Monitoring of large distributed networks requires the deployment of several probes at different network locations where traffic to be analyzed is flowing. Each probe analyzes the traffic and sends the monitoring data toward a centralized management station often using protocols such as NetFlow and IPFIX. As each probe monitors a part of the traffic, the data collector has the responsibility of merging data coming from all the probes and correlate information. This task adds extra load on collectors and prevents traffic information to be available until it has been correlated, thus preventing (near) realtime traffic monitoring. This paper describes how the microcloud architecture can be used to provide real-time traffic monitoring and correlation on large distributed environments where monitoring traffic is analyzed by several probes that collectively concur to the monitoring task. This work has been successfully validated on using this architecture for monitoring the. It DNS ccTLD and a large 3G mobile network with million of users. © 2013 IEEE.

Ugolini A.,University of Florence | Galanti G.,University of Florence | Mercatelli L.,CNR Institute of Neuroscience
Journal of Experimental Biology | Year: 2012

To return to the ecologically optimal zone of the beach, the sandhopper Talitrus saltator (Montagu) maintains a constant sea-land direction based on the sun and moon compasses. In this study, we investigated the role of the skylight gradient of luminance in sun and moon identification under natural and artificial conditions of illumination. Clock-shifted (inverted) sandhoppers tested under the sun (during their subjective night) and under the full moon (during their subjective day) exhibit orientation in accordance with correct identification of the sun and the moon at night. Tested in artificial conditions of illumination at night without the artificial gradient of luminance, the artificial astronomical cue is identified as the moon even when the conditions of illumination allow sun compass orientation during the day. When the artificial gradient of luminance is added, the artificial astronomical cue is identified as the sun. The role of the sky gradient of luminance in sun and moon identification is discussed on the basis of present and past findings. © 2012. Published by The Company of Biologists Ltd.

Adessi A.,University of Florence | De Philippis R.,University of Florence | De Philippis R.,CNR Institute of Neuroscience
International Journal of Hydrogen Energy | Year: 2014

H2 is a clean, renewable and energy-efficient fuel. However, in order for it to be a fuel effectively utilizable at an industrial level, key issues about its economically and environmentally sustainable production have still to be solved. Microbial hydrogen production is a process with a low environmental impact and, among microbial processes, photofermentation is considered a promising and sustainable solution. However, the energy input for the biological processes is still higher than the energy output in the form of H2 gas. One possibility for improving this ratio is to increase the efficiency of the process while at the same time reducing electricity consumption, both of which relate to the issue of an optimal photobioreactor design. This review focuses on recent advances made in photobioreactor design towards higher light conversion efficiency, a greater hydrogen production rate and substrate conversion in hydrogen production processes carried out with purple non sulfur bacteria, giving particular attention to the light source and to illumination protocols. Recent achievements in outdoor hydrogen production in large scale photobioreactors are also reviewed. © 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserver.

Giuffrida A.,CNR Institute of Neuroscience | Maccarrone G.,University of Catania | Cucinotta V.,University of Catania | Orlandini S.,University of Florence | Contino A.,University of Catania
Journal of Chromatography A | Year: 2014

This review highlights recent progresses in the chiral recognition and separation of amino acid enantiomers obtained by capillary electromigration techniques, using different chiral selectors and especially cyclodextrins, covering the literature published from January 2010 to March 2014. Sections are dedicated to the use of derivatization reagents and to the possibility to enantioseparate underivatized amino acids by using either ligand exchange capillary electrophoresis (LECE) and capillary electrophoresis (CE) coupled on line with mass spectrometry. A short insight on frontier nanomaterials is also given. © 2014 Elsevier B.V.

Ross J.,University of Western Australia | Burr D.C.,University of Western Australia | Burr D.C.,University of Florence | Burr D.C.,CNR Institute of Neuroscience
Journal of Vision | Year: 2010

We have recently suggested that numerosity is a primary sensory attribute, and shown that it is strongly susceptible to adaptation. Here we use the Method of Single Stimuli to show that observers can extract a running average of numerosity of a succession of stimuli to use as a standard of comparison for subsequent stimuli. On separate sessions observers judged whether the perceived numerosity or density of a particular trial was greater or less than the average of previous stimuli. Thresholds were as precise for this task as for explicit comparisons of test with standard stimuli. Importantly, we found no evidence that numerosity judgments are mediated by density. Under all conditions, judgements of numerosity were as precise as those of density. Thresholds in intermingled conditions, where numerosity varied unpredictably with density, were as precise as the blocked thresholds. Judgments in constant-density conditions were more precise thresholds than those in variable-density conditions, and numerosity judgements in conditions of constant-numerosity showed no tendency to follow density. We further report the novel finding that perceived numerosity increases with decreasing luminance, whereas texture density does not, further evidence for independent processing of the two attributes. All these measurements suggest that numerosity judgments can be, and are, made independently of judgments of the density of texture. © ARVO.

Messori L.,University of Florence | Merlino A.,CNR Institute of Neuroscience | Merlino A.,University of Naples Federico II
Dalton Transactions | Year: 2014

A crystallographic study of the adduct formed between hen egg white lysozyme (HEWL) and NAMI-A, an established ruthenium(iii) anticancer agent in clinical trials, is presented here. The X-ray structure reveals that NAMI-A coordinates the protein, as a naked ruthenium ion, at two distinct sites (namely Asp101 or Asp119) after releasing all its original ligands (DMSO, imidazole and Cl-). Structural data of the HEWL/NAMI-A adduct are compared with those previously obtained for the HEWL adduct of AziRu, a NAMI-A analogue bearing a pyridine in place of imidazole. The present results further support the view that NAMI-A exerts its biological effects acting as a classical "prodrug" first undergoing activation and then causing extensive metalation of relevant protein targets. It is also proposed that the original Ru-ligands, although absent in the final adduct, play a major role in directing the ruthenium center to its ultimate anchoring site on the protein surface. This journal is © the Partner Organisations 2014.

Esposito R.,University of Naples Federico II | Martelli F.,University of Florence | De Nicola S.,CNR Institute of Neuroscience
Optics Letters | Year: 2014

We have developed a theoretical model for photon migration through scattering media in the presence of an absorbing in homogeneity. A closed-form solution for the average diffuse intensity has been obtained through an iterative approximation scheme of the steady-state diffusion equation. The model describes absorbing defects in a wide range of values. Comparisons with the results of Monte Carlo simulations show that the error of the model is lower than 3% for size inclusion lower than 4 mm and absorption contrast up to the threshold value of the "black defect." The proposed model provides a tractable mathematical basis for diffuse optical and photoacoustic tomographic reconstruction techniques. © 2014 Optical Society of America.

Schwarzlander M.,University of Bonn | Murphy M.P.,MRC Mitochondrial Biology Unit | Duchen M.R.,University College London | Logan D.C.,University of Angers | And 7 more authors.
Trends in Cell Biology | Year: 2012

Mitochondrial free radicals and redox poise are central to metabolism and cell fate. Their measurement in living cells remains a major challenge and their in vivo dynamics are poorly understood. Reports of 'superoxide flashes' in single mitochondria have therefore been perceived as a major breakthrough: single mitochondria expressing the genetically encoded sensor circularly permuted yellow fluorescent protein (cpYFP) display spontaneous flashes of fluorescence that are responsive to metabolic changes and stressors. We critically review the evidence that underpins the interpretation of mitochondrial cpYFP flashes as bursts of superoxide production and conclude that flashes do not represent superoxide bursts but instead are caused by transient alkalinisation of the mitochondrial matrix. We provide a revised framework that will help to clarify the interpretation of mitochondrial flashes. © 2012 Elsevier Ltd.

Baroncelli L.,Normal School of Pisa | Braschi C.,University of Florence | Spolidoro M.,Normal School of Pisa | Begenisic T.,Normal School of Pisa | And 3 more authors.
Cell Death and Differentiation | Year: 2010

Environmental enrichment (EE) is known to profoundly affect the central nervous system (CNS) at the functional, anatomical and molecular level, both during the critical period and during adulthood. Recent studies focusing on the visual system have shown that these effects are associated with the recruitment of previously unsuspected neural plasticity processes. At early stages of brain development, EE triggers a marked acceleration in the maturation of the visual system, with maternal behaviour acting as a fundamental mediator of the enriched experience in both the foetus and the newborn. In adult brain, EE enhances plasticity in the cerebral cortex, allowing the recovery of visual functions in amblyopic animals. The molecular substrate of the effects of EE on brain plasticity is multi-factorial, with reduced intracerebral inhibition, enhanced neurotrophin expression and epigenetic changes at the level of chromatin structure. These findings shed new light on the potential of EE as a non-invasive strategy to ameliorate deficits in the development of the CNS and to treat neurological disorders. © 2010 Macmillan Publishers Limited All rights reserved.

Gori M.,Italian Institute of Technology | Sandini G.,Italian Institute of Technology | Martinoli C.,Instituto David Chiossone | Burr D.,University of Florence | Burr D.,CNR Institute of Neuroscience
Current Biology | Year: 2010

A long-standing question, going back at least 300 years to Berkeley's famous essay, is how sensory systems become calibrated with physical reality. We recently showed [1] that children younger than 8-10 years do not integrate visual and haptic information optimally, but that one or the other sense prevails: touch for size and vision for orientation discrimination. The sensory dominance may reflect crossmodal calibration of vision and touch, where the more accurate sense calibrates the other. This hypothesis leads to a clear prediction: that lack of clear vision at an early age should affect calibration of haptic orientation discrimination. We therefore measured size and orientation haptic discrimination thresholds in 17 congenitally visually impaired children (aged 5-19). Haptic orientation thresholds were greatly impaired compared with age-matched controls, whereas haptic size thresholds were at least as good, and often better. One child with a late-acquired visual impairment stood out with excellent orientation discrimination. The results provide strong support for our crossmodal calibration hypothesis. © 2010 Elsevier Ltd. All rights reserved.

Adams F.,University of Antwerp | Barbante C.,CNR Institute of Neuroscience | Barbante C.,University of Venice
Talanta | Year: 2012

In this tutorial review we give a concise and general overview of the development of imaging analytical techniques from its early stages in the late 1950s up to the present. Analytical techniques that are available for the characterization of the atomic and molecular composition as well as the structure at the bulk level often fail for the analysis of heterogeneous materials. Over the last 50 years a number of specialized analytical techniques were developed - or adapted from existing techniques - that, with time, matured into powerful tools for visualizing structural and compositional heterogeneity in nanotechnology and for the study of natural objects. These techniques evolved first at the microscopic and then the mesoscopic level (the range 100-1,000 nm), and later onto the nanoscopic scale between a few nm and 100 nm, where quantum effects start affecting the properties of materials. © 2012 Elsevier B.V. All rights reserved.

Barzagli F.,CNR Institute of Neuroscience | Mani F.,CNR Institute of Neuroscience | Mani F.,University of Florence | Peruzzini M.,CNR Institute of Neuroscience
International Journal of Greenhouse Gas Control | Year: 2013

In the present study, an efficient process for CO2 capture using some AMP-alkanolamine blends, namely DEA, MDEA, MMEA, DIPA, in non-aqueous solvents has been described. The solvents used are mixtures of ethylene glycol or 1,2-propandiol with either methanol or ethanol. Additionally, either pure 1-propanol or diethylene glycol monomethyl ether have been also employed. Throughout the whole set of experiments, the amine solutions were continuously circulated in a closed cycle between the absorber (set at 20°C) and the desorber (set at 65, 70, 75, 80°C). The CO2 absorption efficiency at equilibrium is in the range 73.1-95.9%. The carbon containing species in the amine-CO2-alcohol equilibria were analyzed by 13C NMR spectroscopy showing that they originate from alcohol and/or amine carboxylation. The AMP-DEA-1-propanol-CO2 system gives a solid compound that has been identified as the carbamate derivative of AMP, [(AMPH)(AMPCO2)], from its 13C solid state NMR spectrum and confirmed by single crystal X-ray structure determination. [(AMPH)(AMPCO2)] instantaneously dissolves in methanol, ethanol and ethylene glycol affording the respective monoalkyl carbonate. The lower stripping temperature of the studied absorbents offers several potential advantages with respect to conventional aqueous solutions of the same alkanolamines, yet preserving comparable efficiency. © 2013 Elsevier Ltd.

Rovero L.,University of Florence | Fratini F.,CNR Institute of Neuroscience
Construction and Building Materials | Year: 2013

This paper presents results of a survey on morphological and mechanical characteristics of the masonries in the Medina of Chefchaouen, XV-XIX century, in the Western Rif in Morocco, aimed at providing the information needed for a correct diagnosis and for the planning of conservation interventions adequate to the specificity of the local building culture. To this end, the work characterizes chemical, physical, and mechanical properties of materials as well as morphological features of traditional masonry walls. In particular, three main types of walls are identified and characterized by the stonework sections. Numerical estimate of compressive strength of the three masonry types is determined both through empirical and analytical formulas and through a method for the assessment of masonry quality based on a Masonry Quality Index (MQI). © 2013 Elsevier Ltd. All rights reserved.

Arrighi R.,University of Florence | Togoli I.,University of Florence | Burr D.C.,University of Florence | Burr D.C.,CNR Institute of Neuroscience
Proceedings of the Royal Society B: Biological Sciences | Year: 2014

Much evidence has accumulated to suggest that many animals, including young human infants, possess an abstract sense of approximate quantity, a number sense. Most research has concentrated on apparent numerosity of spatial arrays of dots or other objects, but a truly abstract sense of number should be capable of encoding the numerosity of any set of discrete elements, however displayed and in whatever sensory modality. Here, we use the psychophysical technique of adaptation to study the sense of number for serially presented items. We show that numerosity of both auditory and visual sequences is greatly affected by prior adaptation to slow or rapid sequences of events. The adaptation to visual stimuli was spatially selective (in external, not retinal coordinates), pointing to a sensory rather than cognitive process. However, adaptation generalized across modalities, from auditory to visual and vice versa. Adaptation also generalized across formats: adaptingtosequen-tial streams of flashes affected the perceived numerosity of spatial arrays. All these results point to a perceptual system that transcends vision and audition to encode an abstract sense of number in space and in time. © 2014 The Royal Society. All rights reserved.

Mendoza M.,ETH Zurich | Herrmann H.J.,ETH Zurich | Succi S.,CNR Institute of Neuroscience | Succi S.,Freiburg Institute for Advanced Studies
Physical Review Letters | Year: 2011

We provide numerical evidence that electronic preturbulent phenomena in graphene could be observed, under current experimental conditions, through current fluctuations, echoing the detachment of vortices past localized micron-sized impurities. Vortex generation, due to micron-sized constriction, is also explored with special focus on the effects of relativistic corrections to the normal Navier-Stokes equations. These corrections are found to cause a delay in the stability breakout of the fluid as well as a small shift in the vortex shedding frequency. © 2011 American Physical Society.

Bonaccorsi J.,CNR Institute of Neuroscience | Berardi N.,CNR Institute of Neuroscience | Berardi N.,University of Florence | Sale A.,CNR Institute of Neuroscience
Frontiers in Neural Circuits | Year: 2014

Amblyopia is the most common form of impairment of visual function affecting one eye, with a prevalence of about 1-5% of the total world population. Amblyopia usually derives from conditions of early functional imbalance between the two eyes, owing to anisometropia, strabismus, or congenital cataract, and results in a pronounced reduction of visual acuity and severe deficits in contrast sensitivity and stereopsis. It is widely accepted that, due to a lack of sufficient plasticity in the adult brain, amblyopia becomes untreatable after the closure of the critical period in the primary visual cortex. However, recent results obtained both in animal models and in clinical trials have challenged this view, unmasking a previously unsuspected potential for promoting recovery even in adulthood. In this context, non invasive procedures based on visual perceptual learning, i.e., the improvement in visual performance on a variety of simple visual tasks following practice, emerge as particularly promising to rescue discrimination abilities in adult amblyopic subjects. This review will survey recent work regarding the impact of visual perceptual learning on amblyopia, with a special focus on a new experimental model of perceptual learning in the amblyopic rat. © 2014 Bonaccorsi, Berardi and Sale.

Wiersma D.S.,University of Florence | Wiersma D.S.,CNR Institute of Neuroscience
Nature Photonics | Year: 2013

What do lotus flowers have in common with human bones, liquid crystals with colloidal suspensions, and white beetles with the beautiful stones of the Taj Mahal? The answer is they all feature disordered structures that strongly scatter light, in which light waves entering the material are scattered several times before exiting in random directions. These randomly distributed rays interfere with each other, leading to interesting, and sometimes unexpected, physical phenomena. This Review describes the physics behind the optical properties of disordered structures and how knowledge of multiple light scattering can be used to develop new applications. The field of disordered photonics has grown immensely over the past decade, ranging from investigations into fundamental topics such as Anderson localization and other transport phenomena, to applications in imaging, random lasing and solar energy. Copyright © 2013 Macmillan Publishers Limited.

Rasanen E.,University of Jyväskylä | Rasanen E.,Harvard University | Rozzi C.A.,CNR Institute of Neuroscience | Pittalis S.,University of Missouri | And 2 more authors.
Physical Review Letters | Year: 2012

Recent advances in the creation and modulation of graphenelike systems are introducing a science of "designer Dirac materials". In its original definition, artificial graphene is a man-made nanostructure that consists of identical potential wells (quantum dots) arranged in an adjustable honeycomb lattice in the two-dimensional electron gas. As our ability to control the quality of artificial graphene samples improves, so grows the need for an accurate theory of its electronic properties, including the effects of electron-electron interactions. Here we determine those effects on the band structure and on the emergence of Dirac points. © 2012 American Physical Society.

Bini D.,CNR Institute of Neuroscience | Damour T.,Institute des Hautes Itudes Scientifiques | Faye G.,University Pierre and Marie Curie
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

The gravitational-wave signal from inspiralling neutron-star-neutron-star (or black-hole-neutron-star) binaries will be influenced by tidal coupling in the system. An important science goal in the gravitational-wave detection of these systems is to obtain information about the equation of state of neutron star matter via the measurement of the tidal polarizability parameters of neutron stars. To extract this piece of information will require accurate analytical descriptions both of the motion and the radiation of tidally interacting binaries. We improve the analytical description of the late inspiral dynamics by computing the next-to-next-to-leading-order relativistic correction to the tidal interaction energy. Our calculation is based on an effective-action approach to tidal interactions and on its transcription within the effective-one-body formalism. We find that second-order relativistic effects (quadratic in the relativistic gravitational potential u=G(m 1+m 2)/(c2r)) significantly increase the effective tidal polarizability of neutron stars by a distance-dependent amplification factor of the form 1+α 1u+α 2u2+ where, say, for an equal-mass binary, α 1=5/4=1.25 (as previously known) and α 2=85/14.07143 (as determined here for the first time). We argue that higher-order relativistic effects will lead to further amplification, and we suggest a Padé-type way of resumming them. We recommend testing our results by comparing resolution-extrapolated numerical simulations of inspiralling binary neutron stars to their effective one-body description. © 2012 American Physical Society.

Nobile C.,CNR Institute of Neuroscience | Striano P.,University of Genoa
Progress in Brain Research | Year: 2014

In the past 2 years, mutations in the PRRT2 gene have been identified in patients and families with a variety of early-onset paroxysmal disorders, including various paroxysmal dyskinesias, benign familial infantile seizures, hemiplegic migraine, and episodic ataxia. In this chapter, we describe the wide clinical spectrum associated with PRRT2 mutations and present the current hypotheses on the underlying pathophysiology. Through its interaction with the presynaptic plasma membrane protein SNAP25, the PRRT2 protein may play a role in synaptic regulation in the cortex and basal ganglia. PRRT2 mutations likely have a loss-of-function effect and result in synaptic deregulation and neuronal hyperexcitability. The molecular bases underlying phenotypic variability are still unclear. Elucidating the molecular pathways linking the genetic defect to its clinical expression will improve treatment of these disorders. © 2014 Elsevier B.V.

Supuran C.T.,University of Florence | Capasso C.,CNR Institute of Neuroscience
Expert Opinion on Therapeutic Targets | Year: 2015

Introduction: The η-class of carbonic anhydrases (CAs, EC was recently discovered as the sixth genetic family of this metalloenzyme superfamily, and seems to be present only in various Plasmodium species, the malaria-provoking pathogens. The present review through detailed biochemical, kinetic and phylogenetic studies afford a clear view regarding the differences between η- and the other CA families. Areas covered: In this review, the authors underlined as the η-CAs, like α-, γ- and δ-class enzymes, have the Zn(II) ion coordinated by three histidine residues and a water molecule. They seem to be more closely related to the α-CAs, but there are notable differences between them, such as the lack of the proton shuttle residue (His64) and gatekeeper residues, Glu106 and Thr199 in the η-CAs, which are conserved in all α-CAs. Expert opinion: Plasmodium falciparum η-CA showed a moderate but significant activity for the CO2 hydration reaction, with a kcat of 1.4 × 105s-1 and a kcat/Km of 5.4 × 106 M-1 × s-1. Several inhibition studies with anions and sulfonamides/sulfamates, allowed the identification of interesting lead compounds. The discovery of η-CA-specific inhibitors may lead to novel such agents with a new mechanism of action. © 2014 Informa UK, Ltd. All rights reserved.

Coltelli M.-B.,University of Pisa | Bronco S.,CNR Institute of Neuroscience | Chinea C.,Central University of Venezuela
Polymer Degradation and Stability | Year: 2010

The blending of PLA with poly(butylene-adipate-co-terephthalate) (PBAT) is a promising strategy to achieve a toughened multiphase material. The blends ductility could be further improved through reactive compatibilization, i.e. inducing the formation of comb PLA-PBAT copolymers during the melt blending. In the present work a non-selective strategy was adopted which consisted in the use of a peroxide, 2,5-Dimethyl-2,5-di(tert-butylperoxy)hexane. The phase morphology development and the final properties (torque, fluidity in the melt, tensile behaviour, thermal and dynamical-mechanical features) of the blends were studied as a function of the peroxide concentration. The elongation at break was improved up to a maximum value thanks to this approach and a corresponding minimum was observed in the value of the dispersed phase diameter. A structural characterization of the macromolecules formed during the reactive process was attempted by using size exclusion chromatography of the blends and comparison with the pure polymers obtained by processing in the presence of the peroxide. © 2009 Elsevier Ltd. All rights reserved.

Gasparinetti S.,Aalto University | Solinas P.,CNR Institute of Neuroscience | Braggio A.,CNR Institute of Neuroscience | Sassetti M.,CNR Institute of Neuroscience | Sassetti M.,University of Genoa
New Journal of Physics | Year: 2014

As the dimensions of physical systems approach the nanoscale, the laws of thermodynamics must be reconsidered due to the increased importance of fluctuations and quantum effects. While the statistical mechanics of small classical systems is relatively well understood, the quantum case still poses challenges. Here, we set up a formalism that allows us to calculate the full probability distribution of energy exchanges between a periodically driven quantum system and a thermalized heat reservoir. The formalism combines Floquet theory with a generalized master equation approach. For a driven two-level system and in the long-time limit, we obtain a universal expression for the distribution, providing clear physical insight into the exchanged energy quanta. We illustrate our approach in two analytically solvable cases and discuss the differences in the corresponding distributions. Our predictions could be directly tested in a variety of systems, including optical cavities and solid-state devices. © 2014 IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

Capasso C.,CNR Institute of Neuroscience | Supuran C.T.,University of Florence
Expert Opinion on Therapeutic Targets | Year: 2015

Introduction: The carbonic anhydrases (CAs, EC, a group of ubiquitously expressed metalloenzymes, are involved in numerous physiological and pathological processes, as well as in the growth and virulence of pathogens belonging to bacteria, fungi and protozoa. Areas covered: CAs belonging to at least four genetic families, the α-, β-, γ- and η-CAs, were discovered and characterized in many pathogens: i) Bacteria encode enzymes from one or more such families, which were investigated as potential drug targets. Inhibition of bacterial CAs by sulfonamides/phenol derivatives lead to inhibition of growth of the pathogen for Helicobacter pylori, Mycobacterium tuberculosis, Brucella suis; ii) Fungi encode for α- and β-CAs, and inhibitors of the sulfonamide, thiol or dithiocarbamate type inhibited the growth of some of them (Malassezia globosa, Candida albicans, Crytpococcus neoformans, etc) in vivo; and iii) Protozoa encode α-, β- or η-CAs. Sulfonamide, thiols and hydroxamates effectively killed such parasites (Trypanosoma cruzi, Leishmania donovani chagasi, Plasmodium falciparum) in vivo. Expert opinion: None of the microorganism CAs is validated as drug targets as yet, but the inhibitors designed against many such enzymes showed interesting in vitro/in vivo results. By interfering with the activity of CAs from microorganisms, both pH homeostasis as well as crucial biosynthetic reactions are impaired, which lead to significant antiinfective effects, not yet exploited for obtaining pharmacological agents. As resistance to the clinically used antiinfectives is a serious healthcare problem worldwide, inhibition of parasite CAs may constitute an alternative approach for obtaining such agents with novel mechanisms of action. © 2015 Taylor & Francis.

Zarghami A.,Islamic Azad University at Science and Research of Fars | Ubertini S.,University of Tuscia | Succi S.,CNR Institute of Neuroscience
Computers and Fluids | Year: 2013

A finite-volume formulation of the lattice Boltzmann method (LBM) is developed, to investigate the thermo-hydrodynamic transport in nanofluids. To this purpose, by considering different forces acting on the nano-particles, a cell-centered scheme is used to discretize the convection operator and the double distribution function model is applied to describe the dynamics of temperature field. To enhance numerical stability, weighting factors are used as flux correctors. The method is employed to simulate nanofluids in plane Poiseuille and backward-facing step flows. Thermo-hydrodynamics characteristics are analyzed with specific emphasis on the effects of the nano-particle concentration on the efficiency of heat transport in the aforementioned settings. © 2013 Elsevier Ltd.

Capasso C.,CNR Institute of Neuroscience | Supuran C.T.,University of Florence
Journal of Enzyme Inhibition and Medicinal Chemistry | Year: 2015

Carbonic anhydrases (CAs, EC are metalloenzymes which catalyze a simple but physiologically crucial reaction in all life Domains, the carbon dioxide hydration to bicarbonate and protons: CO2+H2O+H+. These enzymes are involved in many physiologic processes, such as photosynthesis, respiration, CO2 transport, as well as metabolism of xenobiotics. Five different, genetically distinct CA families are known to date: the α-, β-, γ-, δ- and ζ-CAs. α-, β- and δ-CAs use Zn(II) ions at the active site, the γ-CAs are probably Fe(II) enzymes (but they are active also with bound Zn(II) or Co(II) ions), whereas the ζ-class uses Cd(II) or Zn(II) to perform the physiologic reaction catalysis. Bacteria encode for enzymes belonging to the α-, β-, and γ-CA classes. They contain zinc ion (Zn2+) in their active site, coordinated by three histidine residues and a water molecule/hydroxide ion (in the α and γ) or by two cysteine and one histidine residues (in the β class), with the fourth ligand being a water molecule/hydroxide ion. Here we propose that bacterial CAs can be used as markers for understanding the evolution and genetic variability of the Gram-positive and Gram-negative bacteria. We addressed several questions such as: (1) why are α-CAs present only in the genome of Gram-negative bacteria; (2) why are α-CAs not present in all Gram-negative bacteria; (3) why do Bacteria show an intricate pattern of CA gene expression; (4) what are the physiologic roles of such diverse CAs in these prokaryotes. We proposed possible answers to the previous questions. Moreover, we speculated on the evolution of the CA classes (α, β and γ) identified in the Gram-negative and -positive bacteria. Our main hypothesis is that from the ancestral Ur-CA, the γ-class arose first, followed by the β-class; the α-class CAs came last it is found only in the Gram-negative bacteria. © 2014 Informa UK Ltd.

Vitiello M.S.,CNR Institute of Neuroscience | Consolino L.,CNR Institute of Neuroscience | Bartalini S.,CNR Institute of Neuroscience | Taschin A.,CNR Institute of Neuroscience | And 4 more authors.
Nature Photonics | Year: 2012

Quantum cascade lasers can be considered the primary achievement of electronic band structure engineering, showing how artificial materials can be created through quantum design to have tailor-made properties that are otherwise non-existent in nature. Indeed, quantum cascade lasers can be used as powerful testing grounds of the fundamental physical parameters determined by their quantum nature, including the intrinsic linewidth of laser emission, which in such lasers is significantly affected by the optical and thermal photon number generated in the laser cavity. Here, we report experimental evidence of linewidth values approaching the quantum limit in far-infrared quantum cascade lasers. Despite the broadening induced by thermal photons, the measured linewidth results narrower than that found in any other semiconductor laser to date. By performing noise measurements with unprecedented sensitivity levels, we highlight the key role of gain medium engineering and demonstrate that properly designed semiconductor-heterostructure lasers can unveil the mechanisms underlying the laser-intrinsic phase noise, revealing the link between device properties and the quantum-limited linewidth. © 2012 Macmillan Publishers Limited. All rights reserved.

Niehaus T.A.,University of Regensburg | Della Sala F.,CNR Institute of Neuroscience
Physica Status Solidi (B) Basic Research | Year: 2012

A generalization of the density functional based tight-binding method (DFTB) for the use with range-separated exchange-correlation functionals is presented. It is based on the generalized Kohn-Sham (GKS) formalism and employs the density matrix as basic variable in the expansion of the energy functional, in contrast to the traditional DFTB scheme. The GKS-TB equations are derived and appropriate integral approximations are discussed in detail. Implementation issues and numerical aspects of the new scheme are also covered. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Bushell A.F.,University of Manchester | Budd P.M.,University of Manchester | Attfield M.P.,University of Manchester | Jones J.T.A.,University of Liverpool | And 6 more authors.
Angewandte Chemie - International Edition | Year: 2013

Organic-organic composite membranes are prepared by in situ crystallization of cage molecules in a polymer of intrinsic microporosity. This allows a direct one-step route to mixed-matrix membranes, starting with a homogeneous molecular solution. Extremely high gas permeabilities are achieved, even after ageing for more than a year, coupled with good selectivity for applications such as CO2 recovery. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Pachucki K.,University of Warsaw | Yerokhin V.A.,Saint Petersburg State Polytechnic University | Cancio Pastor P.,CNR Institute of Neuroscience | Cancio Pastor P.,University of Florence
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2012

The combined fine and hyperfine structure of the 23P states in 3He is calculated within the framework of nonrelativistic quantum electrodynamics. The calculation accounts for the effects of order mα6 and increases the accuracy of theoretical predictions by an order of magnitude. The results obtained are in good agreement with recent spectroscopic measurements in 3He. © 2012 American Physical Society.

Heintze E.,University of Stuttgart | El Hallak F.,University of Stuttgart | Clauss C.,University of Stuttgart | Rettori A.,University of Florence | And 5 more authors.
Nature Materials | Year: 2013

Controlling the speed at which systems evolve is a challenge shared by all disciplines, and otherwise unrelated areas use common theoretical frameworks towards this goal. A particularly widespread model is Glauber dynamics, which describes the time evolution of the Ising model and can be applied to any binary system. Here we show, using molecular nanowires under irradiation, that Glauber dynamics can be controlled by a novel domain-wall kickoff mechanism. In contrast to known processes, the kickoff has unambiguous fingerprints, slowing down the spin-flip attempt rate by several orders of magnitude, and following a scaling law. The required irradiance is very low, a substantial improvement over present methods of magneto-optical switching. These results provide a new way to control and study stochastic dynamic processes. Being general for Glauber dynamics, they can be extended to different kinds of magnetic nanowires and to numerous fields, ranging from social evolution to neural networks and chemical reactivity. © 2013 Macmillan Publishers Limited. All rights reserved.

Gabbrielli M.,University of Florence | Gabbrielli M.,CNR Institute of Neuroscience | Pezze L.,CNR Institute of Neuroscience | Smerzi A.,CNR Institute of Neuroscience
Physical Review Letters | Year: 2015

Unstable spinor Bose-Einstein condensates are ideal candidates to create nonlinear three-mode interferometers. Our analysis goes beyond the standard SU(1,1) parametric approach and therefore provides the regime of parameters where sub-shot-noise sensitivities can be reached with respect to the input total average number of particles. Decoherence due to particle losses and finite detection efficiency are also considered. © 2015 American Physical Society. © 2015 American Physical Society.

Calandra M.,French National Center for Scientific Research | Profeta G.,CNR Institute of Neuroscience | Mauri F.,French National Center for Scientific Research
Physical Review B - Condensed Matter and Materials Physics | Year: 2010

We develop a first-principles scheme to calculate adiabatic and nonadiabatic phonon frequencies in the full Brillouin zone. The method relies on the stationary properties of a force-constant functional with respect to the first-order perturbation of the electronic charge density and on the localization of the deformation potential in the Wannier function basis. This allows for calculation of phonon-dispersion curves free from convergence issues related to Brillouin-zone sampling. In addition our approach justifies the use of the static screened potential in the calculation of the phonon linewidth due to decay in electron-hole pairs. We apply the method to the calculation of the phonon dispersion and electron-phonon coupling in MgB2 and CaC 6. In both compounds we demonstrate the occurrence of several Kohn anomalies, absent in previous calculations, that are manifest only after careful electron- and phonon-momentum integration. In MgB2, the presence of Kohn anomalies on the E2g branches improves the agreement with measured phonon spectra and affects the position of the main peak in the Eliashberg function. In CaC6 we show that the nonadiabatic effects on in-plane carbon vibrations are not localized at zone center but are sizable throughout the full Brillouin zone. Our method opens perspectives in large-scale first-principles calculations of dynamical properties and electron-phonon interaction. © 2010 The American Physical Society.

Vynck K.,University of Florence | Burresi M.,University of Florence | Burresi M.,CNR Institute of Neuroscience | Riboli F.,University of Florence | And 2 more authors.
Nature Materials | Year: 2012

Elaborating reliable and versatile strategies for efficient light coupling between free space and thin films is of crucial importance for new technologies in energy efficiency. Nanostructured materials have opened unprecedented opportunities for light management, notably in thin-film solar cells. Efficient coherent light trapping has been accomplished through the careful design of plasmonic nanoparticles and gratings, resonant dielectric particles and photonic crystals. Alternative approaches have used randomly textured surfaces as strong light diffusers to benefit from their broadband and wide-angle properties. Here, we propose a new strategy for photon management in thin films that combines both advantages of an efficient trapping due to coherent optical effects and broadband/wide-angle properties due to disorder. Our approach consists of the excitation of electromagnetic modes formed by multiple light scattering and wave interference in two-dimensional random media. We show, by numerical calculations, that the spectral and angular responses of thin films containing disordered photonic patterns are intimately related to the in-plane light transport process and can be tuned through structural correlations. Our findings, which are applicable to all waves, are particularly suited for improving the absorption efficiency of thin-film solar cells and can provide a new approach for high-extraction-efficiency light-emitting diodes. © 2012 Macmillan Publishers Limited. All rights reserved.

Adams F.C.,University of Antwerp | Barbante C.,CNR Institute of Neuroscience | Barbante C.,University of Venice
Spectrochimica Acta - Part B Atomic Spectroscopy | Year: 2013

Nanoscience has outgrown its infancy, and nanotechnology has found important applications in our daily life - with many more to come. Although the central concepts of the nano world, namely the changes of particular physical properties on the length scale of individual atoms and molecules, have been known and developed for quite some time already, experimental advances since the 1980s and recognition of the potential of nanomaterials led to a genuine breakthrough of the inherently multidisciplinary nanoscience field. Analytical nanoscience and nanotechnology and especially the use of micro and nano electro mechanical systems, of the quantum dots and of mass spectrometry, currently provide one of the most promising avenues for developments in analytical science, derived from their two main fields of action, namely (a) the analysis of nano-structured materials and (b) their use as new tools for analysis. An overview is given of recent developments and trends in the field, highlighting the importance and point out future directions, while also touching drawbacks, such as emerging concerns about health and environmental issues. © 2013 Elsevier B.V.

Taschin A.,University of Florence | Bartolini P.,University of Florence | Eramo R.,University of Florence | Eramo R.,CNR Institute of Neuroscience | And 2 more authors.
Nature Communications | Year: 2013

The liquid and supercooled states of water show a series of anomalies whose nature is debated. A key role is attributed to the formation of structural aggregates induced by critical phenomena occurring deep in the supercooled region; the nature of the water anomalies and of the hidden critical processes remains elusive. Here we report a time-resolved optical Kerr effect investigation of the vibrational dynamics and relaxation processes in supercooled bulk water. The experiment measures the water intermolecular vibrations and the structural relaxation process in an extended temperature range, and with unprecedented data quality. A mode-coupling analysis of the experimental data enables to characterize the intermolecular vibrational modes and their interplay with the structural relaxation process. The results bring evidence of the coexistence of two local configurations, which are interpreted as high-density and low-density water forms, with an increasing weight of the latter at low temperatures. © 2013 Macmillan Publishers Limited. All rights reserved.

Grigorenko A.N.,University of Manchester | Polini M.,CNR Institute of Neuroscience | Novoselov K.S.,University of Manchester
Nature Photonics | Year: 2012

Two rich and vibrant fields of investigation - graphene physics and plasmonics - strongly overlap. Not only does graphene possess intrinsic plasmons that are tunable and adjustable, but a combination of graphene with noble-metal nanostructures promises a variety of exciting applications for conventional plasmonics. The versatility of graphene means that graphene-based plasmonics may enable the manufacture of novel optical devices working in different frequency ranges - from terahertz to the visible - with extremely high speed, low driving voltage, low power consumption and compact sizes. Here we review the field emerging at the intersection of graphene physics and plasmonics. © 2012 Macmillan Publishers Limited. All rights reserved.

Amir R.J.,University of California at Santa Barbara | Albertazzi L.,University of California at Santa Barbara | Albertazzi L.,CNR Institute of Neuroscience | Willis J.,University of California at Santa Barbara | And 3 more authors.
Angewandte Chemie - International Edition | Year: 2011

Dual action: Trackable multifunctional dendritic scaffolds with high internal loading capacity were synthesized based on a PEG core. Orthogonal functionalization of chain-end and internal groups allowed the dendrimers to be both labeled and loaded with releasable dyes for simultaneous monitoring of the dendritic carrier and release of the dye payload inside living cells (see picture). Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Burr D.C.,University of Florence | Burr D.C.,CNR Institute of Neuroscience | Morrone M.C.,University of Pisa
Philosophical Transactions of the Royal Society B: Biological Sciences | Year: 2011

How our perceptual experience of the world remains stable and continuous in the face of continuous rapid eye movements still remains a mystery. This review discusses some recent progress towards understanding the neural and psychophysical processes that accompany these eye movements. We firstly report recent evidence from imaging studies in humans showing that many brain regions are tuned in spatiotopic coordinates, but only for items that are actively attended. We then describe a series of experiments measuring the spatial and temporal phenomena that occur around the time of saccades, and discuss how these could be related to visual stability. Finally, we introduce the concept of the spatio-temporal receptive field to describe the local spatiotopicity exhibited by many neurons when the eyes move. This journal is © 2011 The Royal Society.

Capasso C.,CNR Institute of Neuroscience | Supuran C.T.,University of Florence
Current Medicinal Chemistry | Year: 2015

The possibility to develop new antibacterial agents raised much interest recently. The main classes of antibiotics clinically used nowadays act towards the inhibition of four classical targets: a) cell wall biosynthesis; b) protein biosynthesis; c) DNA and RNA biosynthesis; d) folate biosynthesis. Recently, carbonic anhydrases (CAs, EC started to be investigated in detail in pathogenic bacteria, in the search for antibiotics with a novel mechanism of action, since it has been demonstrated that in many bacteria, CAs are essential for the life cycle of the organism and that their inhibition leads to growth impairment or growth defects of the pathogen. CAs catalyze a simple but physiologically relevant reaction in all life kingdoms, carbon dioxide hydration to bicarbonate and protons. Several classes of CA inhibitors (CAIs) are known to date: the metal complexing anions and the unsubstituted sulfonamides, which bind to the Zn(II) ion of the enzyme either by substituting the non-protein zinc ligand or add to the metal coordination sphere, generating trigonal-bipyramidal species are the classical, most frequently investigated ones. In many cases effective inhibitors were detected, some of which also inhibited the bacterial growth in vivo. However, very few of the detected inhibitors were also selective for the bacterial over the human, off target isoforms such as hCA II. Using structure-based drug design processes, we estimate that it will be possible to achieve the desired selectivity for inhibiting preferentially the bacterial but not the host CA isoforms. © 2015 Bentham Science Publishers.

Pratali L.,CNR Institute of Neuroscience | Cavana M.,U. B. Rianimazione e Ambulatorio Medicina di Montagna | Sicari R.,CNR Institute of Neuroscience | Picano E.,CNR Institute of Neuroscience
Critical Care Medicine | Year: 2010

Objective: The ultrasound lung comets detected by chest sonography are a simple, noninvasive, semiquantitative sign of increased extravascular lung water. The aim of this study was to evaluate, by chest sonography, the incidence of interstitial pulmonary edema in recreational high-altitude climbers. Design: Observational study. SUBJECTS: Eighteen healthy subjects (mean age 45 ± 10 yrs, ten males) participating in a high-altitude trek in Nepal. Interventions: Chest and cardiac sonography at sea level and at different altitudes during ascent. Ultrasound lung comets were evaluated on anterior chest at 28 predefined scanning sites. MEASUREMENTS AND MAIN RESULTS: At individual patient analysis, ultrasound lung comets during ascent appeared in 15 of 18 subjects (83%) at 3440 m above sea level and in 18 of 18 subjects (100%) at 4790 m above sea level in the presence of normal left and right ventricular function and pulmonary artery systolic pressure rise (sea level = 24 ± 5 mm Hg vs. peak ascent = 42 ± 11 mm Hg, p <.001). Ultrasound lung comets were absent at baseline (day 2, altitude 1350 m, 1.06 ± 1.3), increased progressively during the ascent (day 14, altitude 5130 m: 16.5 ± 8; p <.001 vs. previous steps), and decreased at descent (day 20, altitude 1355 m: 2.9 ± 1.7; p = nonsignificant vs. baseline). An ultrasound lung comet score showed a negative correlation with o2 saturation (R =-.7; p <.0001). Conclusions: In recreational climbers, chest sonography revealed a high prevalence of clinically silent interstitial pulmonary edema mirrored by decreased o2 saturation, whereas no statistically significant relationship with pulmonary artery systolic pressure was observed during ascent. © 2010 by the Society of Critical Care Medicine and Lippincott Williams & Wilkins.

Zavatta A.,CNR Institute of Neuroscience | Zavatta A.,University of Florence | Fiurasek J.,Palacky University | Bellini M.,CNR Institute of Neuroscience | Bellini M.,University of Florence
Nature Photonics | Year: 2011

Noise is the price to pay when trying to clone or amplify arbitrary quantum states. However, the quantum noise associated with linear phase-insensitive amplifiers can be avoided by relaxing the requirement of a deterministic operation. Here we present the experimental realization of a novel concept of a probabilistic noiseless linear amplifier that is able to amplify coherent states at the highest levels of effective gain and final state fidelity ever reached. Based on a sequence of photon addition and subtraction, this high-fidelity amplification scheme is likely to become an essential tool for applications of quantum communication and metrology. © 2011 Macmillan Publishers Limited. All rights reserved.

Aagten-Murphy D.,University of Florence | Cappagli G.,University of Florence | Burr D.,University of Florence | Burr D.,CNR Institute of Neuroscience
Acta Psychologica | Year: 2014

Expert musicians are able to time their actions accurately and consistently during a musical performance. We investigated how musical expertise influences the ability to reproduce auditory intervals and how this generalises across different techniques and sensory modalities. We first compared various reproduction strategies and interval length, to examine the effects in general and to optimise experimental conditions for testing the effect of music, and found that the effects were robust and consistent across different paradigms. Focussing on a 'ready-set-go' paradigm subjects reproduced time intervals drawn from distributions varying in total length (176, 352 or 704. ms) or in the number of discrete intervals within the total length (3, 5, 11 or 21 discrete intervals). Overall, Musicians performed more veridical than Non-Musicians, and all subjects reproduced auditory-defined intervals more accurately than visually-defined intervals. However, Non-Musicians, particularly with visual stimuli, consistently exhibited a substantial and systematic regression towards the mean interval. When subjects judged intervals from distributions of longer total length they tended to regress more towards the mean, while the ability to discriminate between discrete intervals within the distribution had little influence on subject error. These results are consistent with a Bayesian model that minimizes reproduction errors by incorporating a central tendency prior weighted by the subject's own temporal precision relative to the current distribution of intervals. Finally a strong correlation was observed between all durations of formal musical training and total reproduction errors in both modalities (accounting for 30% of the variance). Taken together these results demonstrate that formal musical training improves temporal reproduction, and that this improvement transfers from audition to vision. They further demonstrate the flexibility of sensorimotor mechanisms in adapting to different task conditions to minimise temporal estimation errors. © 2013 Elsevier B.V.

Rizza C.,University of Insubria | Rizza C.,CNR Institute of Neuroscience | Ciattoni A.,CNR Institute of Neuroscience
Optics Letters | Year: 2013

Wetheoretically investigate the homogenization of the dielectric response to transverse electric waves of a transverse grating characterized by the Kapitza condition; i.e., the permittivity is rapidly modulated with a modulation depth scaling as the large wavelength-to-modulation-period ratio. We show that the resulting effective dielectric permittivity, in addition to the standard average of the underlying dielectric profile, has a further contribution arising from the fast and deep dielectric modulation. Such a contribution turns out to be comparable with the other one and hence can provide an additional method for designing dielectric metamaterials. As an example, we discuss an effective metal-to-dielectric transition produced by the Kapitza contribution obtained by changing the grating depth, a remarkable result for applications involving epsilon-near-zero metamaterial design. © 2013 Optical Society of America.

De Rosis A.,University of Bologna | Falcucci G.,Parthenope University of Naples | Ubertini S.,University of Tuscia | Ubertini F.,University of Bologna | Succi S.,CNR Institute of Neuroscience
Communications in Computational Physics | Year: 2013

This work is concerned with the modelling of the interaction of fluid flow with flexibly supported rigid bodies. The fluid flow is modelled by Lattice-Boltzmann Method, coupled to a set of ordinary differential equations describing the dynamics of the solid body in terms its elastic and damping properties. The time discretization of the body dynamics is performed via the Time Discontinuous GalerkinMethod. Several numerical examples are presented and highlight the robustness and efficiency of the proposed methodology, by means of comparisons with previously published results. The examples show that the present fluid-structure method is able to capture vortexinduced oscillations of flexibly-supported rigid body. © 2013 Global-Science Press.

Cernuto G.,University of Insubria | Masciocchi N.,University of Insubria | Cervellino A.,Paul Scherrer Institute | Colonna G.M.,Stazione Sperimentale per la Seta | And 2 more authors.
Journal of the American Chemical Society | Year: 2011

Nanocrystalline TiO 2 samples, prepared forsmart textiles applications by the sol-gel technique in acidic or basic media, have been characterized by synchrotron X-ray powder diffraction and total scattering methods based on a fast implementation of the Debye function and original algorithms for sampling interatomic distances. Compared to the popular and widely used Rietveld-based approaches, our method is able to simultaneously model both Bragg and diffuse contributions and to quantitatively extract either sizes and size distribution information from the experimental data. The photocatalytic activity of the investigated samples is here systematically correlated to the average sizes and size distributions of anisotropically shaped coherent domains, modeled according to bivariate populations of nanocrystals grown along two normal directions. © 2011 American Chemical Society.

Trincado M.,ETH Zurich | Grutzmacher H.,ETH Zurich | Vizza F.,CNR Institute of Neuroscience | Bianchini C.,CNR Institute of Neuroscience
Chemistry - A European Journal | Year: 2010

The combination of the d8 RhI diolefin amide [Rh(trop2N)(PPh3)] (trop2N=bis(5-H-dibenzo-[a, d]cyclohepten-5-yl)amide) and a palladium heterogeneous catalyst results in the formation of a superior catalyst system for the dehydrogenative coupling of alcohols. The overall process represents a mild and direct method for the synthesis of aromatic and heteroaromatic carboxylic acids for which inactivated olefins can be used as hydrogen acceptors. Allyl alcohols are also applicable to this coupling reaction and provide the corresponding saturated aliphatic carboxylic acids. This transformation has been found to be very efficient in the presence of silica-supported palladium nanoparticles. The dehydrogenation of benzyl alcohol by the rhodium amide, [Rh]N, follows the well established mechanism of metal-ligand bifunctional catalysis. The resulting amino hydride complex, [RhH]NH, transfers a H2 molecule to the Pd nanoparticles, which, in turn, deliver hydrogen to the inactivated alkene. Thus a domino catalytic reaction is developed which promotes the reaction R-CH 2-OH+NaOH+ 2 alkene→R-COONa+2 alkane. © 2010 Wiley-VCH Verlag GmbH & Co. KGaA.

Ciattoni A.,CNR Institute of Neuroscience | Marinelli R.,University of L'Aquila | Rizza C.,University of Insubria | Palange E.,University of L'Aquila
Applied Physics B: Lasers and Optics | Year: 2013

We consider a mixture of metal-coated quantum dots dispersed in a polymer matrix and, using a modified version of the standard Maxwell-Garnett mixing rule, we prove that the mixture parameters (particles radius, quantum dots gain, etc.) can be chosen so that the effective medium permittivity has an absolute value very close to zero in the near-infrared, i.e. |Re ε| at the same near-infrared wavelength. Resorting to full-wave simulations, we investigate the accuracy of the effective medium predictions and we relate their discrepancy with rigorous numerical results to the fact that |ε| is a critical requirement. We show that a simple method for reducing this discrepancy, and hence for achieving a prescribed and very small value of |ε|, consists in a subsequent fine-tuning of the nanoparticles volume filling fraction. © 2012 Springer-Verlag Berlin Heidelberg.

Tognini P.,CNR Institute of Neuroscience | Napoli D.,CNR Institute of Neuroscience | Napoli D.,Normal School of Pisa | Tola J.,CNR Institute of Neuroscience | And 5 more authors.
Nature Neuroscience | Year: 2015

DNA methylation is an epigenetic repressor mark for transcription dynamically regulated in neurons. We analyzed visual experience regulation of DNA methylation in mice and its involvement in ocular dominance plasticity of the developing visual cortex. Monocular deprivation modulated the expression of factors controlling DNA methylation and exerted opposite effects on DNA methylation and hydroxymethylation in specific plasticity genes. Inhibition of DNA methyltrasferase (DNMT) blocked molecular and functional effects of monocular deprivation, partially reversing the monocular deprivation transcriptional program. © 2015 Nature America, Inc.

Solinas P.,CNR Institute of Neuroscience | Gasparinetti S.,ETH Zurich
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2015

We propose an approach to define and measure the statistics of work, internal energy and dissipated heat in a driven quantum system. In our framework the presence of a physical detector arises naturally and work and its statistics can be investigated in the most general case. In particular, we show that the quantum coherence of the initial state can lead to measurable effects on the moments of the work done on the system. At the same time, we recover the known results if the initial state is a statistical mixture of energy eigenstates. Our method can also be applied to measure the dissipated heat in an open quantum system. By sequentially coupling the system to a detector, we can track the energy dissipated in the environment while accessing only the system degrees of freedom. © 2015 American Physical Society.

Bercioux D.,Donostia International Physics Center | Bercioux D.,Ikerbasque | Bercioux D.,Free University of Berlin | Lucignano P.,CNR Institute of Neuroscience | Lucignano P.,University of Naples Federico II
Reports on Progress in Physics | Year: 2015

In this review article we describe spin-dependent transport in materials with spin-orbit interaction of Rashba type. We mainly focus on semiconductor heterostructures, however we consider topological insulators, graphene and hybrid structures involving superconductors as well. We start from the Rashba Hamiltonian in a two dimensional electron gas and then describe transport properties of two- and quasi-one-dimensional systems. The problem of spin current generation and interference effects in mesoscopic devices is described in detail. We address also the role of Rashba interaction on localisation effects in lattices with nontrivial topology, as well as on the Ahronov-Casher effect in ring structures. A brief section, in the end, describes also some related topics including the spin-Hall effect, the transition from weak localisation to weak anti localisation and the physics of Majorana fermions in hybrid heterostructures involving Rashba materials in the presence of superconductivity. © 2015 IOP Publishing Ltd.

Ferraroni M.,University of Florence | Del Prete S.,CNR Institute of Neuroscience | Vullo D.,University of Florence | Capasso C.,CNR Institute of Neuroscience | Supuran C.T.,University of Florence
Acta Crystallographica Section D: Biological Crystallography | Year: 2015

Carbonic anhydrase (CA) is a zinc enzyme that catalyzes the reversible conversion of carbon dioxide to bicarbonate (hydrogen carbonate) and a proton. CAs have been extensively investigated owing to their involvement in numerous physiological and pathological processes. Currently, CA inhibitors are widely used as antiglaucoma, anticancer and anti-obesity drugs and for the treatment of neurological disorders. Recently, the potential use of CA inhibitors to fight infections caused by protozoa, fungi and bacteria has emerged as a new research direction. In this article, the cloning and kinetic characterization of the β-CA from Vibrio cholerae (VchCAβ) are reported. The X-ray crystal structure of this new enzyme was solved at 1.9 Å resolution from a crystal that was perfectly merohedrally twinned, revealing a tetrameric type II β-CA with a closed active site in which the zinc is tetrahedrally coordinated to Cys42, Asp44, His98 and Cys101. The substrate bicarbonate was found bound in a noncatalytic binding pocket close to the zinc ion, as reported for a few other β-CAs, such as those from Escherichia coli and Haemophilus influenzae. At pH 8.3, the enzyme showed a significant catalytic activity for the physiological reaction of the hydration of CO2 to bicarbonate and protons, with the following kinetic parameters: a k cat of 3.34 × 105s-1 and a k cat/K m of 4.1 × 107M-1s-1. The new enzyme, on the other hand, was poorly inhibited by acetazolamide (K i of 4.5μM). As this bacterial pathogen encodes at least three CAs, an α-CA, a β-CA and a γ-CA, these enzymes probably play an important role in the life cycle and pathogenicity of Vibrio, and it cannot be excluded that interference with their activity may be exploited therapeutically to obtain antibiotics with a different mechanism of action. © 2015 International Union of Crystallography.

Pavan G.M.,University of Applied Sciences and Arts Southern Switzerland | Albertazzi L.,CNR Institute of Neuroscience | Albertazzi L.,Center for Nanotechnology Innovation | Danani A.,University of Applied Sciences and Arts Southern Switzerland
Journal of Physical Chemistry B | Year: 2010

This paper reports a molecular dynamic study to explore the diverse behavior of different generations of poly(amidoamine) (PAMAM) dendrimers in binding siRNA. Our models show good accordance with experimental measurements. Simulations demonstrate that the molecular flexibility of PAMAMs plays a crucial role in the binding event, which is controlled by the modulation between enthalpy and entropy of binding. Importantly, the ability of dendrimers to adapt to siRNA is strongly dependent on the generation and on the pH due to backfolding. While G4 demonstrates good adaptability to siRNA, G6 behaves like a rigid sphere with a consistent loss in the binding affinity. G5 shows a hybrid behavior, maintaining rigid and flexible aspects, with a strong dependence of its properties on the pH. To define the "best binder", the mere energetic definition of binding affinity appears to be no longer effective and a novel concept of "efficiency" should be considered, being the balance between enthalpy and entropy of binding indivisible from the structural flexibility. With this aim, we propose an original criterion to define and rank the ability of these molecules to adapt their structure to bind a charged target. © 2010 American Chemical Society.

Alma Materials Studiorum Universita` Of Bologna and CNR Institute of Neuroscience | Date: 2012-03-06

The invention relates to a conductive fiber material comprising a base fiber material (1) including a textile fiber, a plurality of nanoparticles (20) deposited on an external surface (10) of said base fiber material, said nanoparticles including one or more metals or metal oxides and a conductive polymer layer deposited on said external surface including nanoparticles.

Sanchez-Gonzalez A.,University of Pisa | Corni S.,CNR Institute of Neuroscience | Mennucci B.,University of Pisa
Journal of Physical Chemistry C | Year: 2011

Plasmon resonances of metal nanoparticles arranged in arrays are known to be coupled, yielding optical properties that are not the simple sum of those of the individual nanoparticles. On top of this, when the nanoparticle array is immersed in a solvent or in a dielectric matrix, the environment is modifying the position and the intensity of the single-particle plasmon resonances and also their coupling. In this article, by means of a hybrid quantum-mechanical/ continuum model, we study the consequences of solvent effects and plasmon couplings on the fluorescence intensity of a dye (naphthalene monoimide) positioned within a four-metal nanoparticle square array. In particular, we analyze the effects of the metal nature (Ag vs Au), interparticle distance, dye-particle distance, dye orientation, and addition of a solvent (dimethylformamide) on the surface-enhanced fluorescence intensity of the dye and on the various quantities that determine such enhancement (radiative and nonradiative decay times, absorption). The conditions that make the effects of the four particles additive are explored, and the results of the hybrid model are tested against those of a fully quantum mechanical model for a dye plus two metal clusters (Ag 20) system. © 2011 American Chemical Society.

Salasnich L.,University of Padua | Salasnich L.,CNR Institute of Neuroscience | Toigo F.,University of Padua
Physics Reports | Year: 2016

We analyze the divergent zero-point energy of a dilute and ultracold gas of atoms in D spatial dimensions. For bosonic atoms we explicitly show how to regularize this divergent contribution, which appears in the Gaussian fluctuations of the functional integration, by using three different regularization approaches: dimensional regularization, momentum-cutoff regularization and convergence-factor regularization. In the case of the ideal Bose gas the divergent zero-point fluctuations are completely removed, while in the case of the interacting Bose gas these zero-point fluctuations give rise to a finite correction to the equation of state. The final convergent equation of state is independent of the regularization procedure but depends on the dimensionality of the system and the two-dimensional case is highly nontrivial. We also discuss very recent theoretical results on the divergent zero-point energy of the D-dimensional superfluid Fermi gas in the BCS-BEC crossover. In this case the zero-point energy is due to both fermionic single-particle excitations and bosonic collective excitations, and its regularization gives remarkable analytical results in the BEC regime of composite bosons. We compare the beyond-mean-field equations of state of both bosons and fermions with relevant experimental data on dilute and ultracold atoms quantitatively confirming the contribution of zero-point-energy quantum fluctuations to the thermodynamics of ultracold atoms at very low temperatures. © 2016 Elsevier B.V.

Secchi S.,CNR Institute of Neuroscience | Schrefler B.A.,University of Padua
International Journal of Fracture | Year: 2012

We present a method for the simulation of 3-D hydraulic fracturing in fully saturated porous media. The discrete fracture(s) is driven by the fluid pressure. A cohesive fracture model is adopted where the fracture follows the face of the elements around the fracture tip which is closest to the normal direction of the maximum principal stress at the fracture tip. No predetermined fracture path is needed. This requires continuous updating of the mesh around the crack tip to take into account the evolving geometry. The updating of the mesh is obtained by means of an efficient mesh generator based on Delaunay tessellation. The governing equations are written in the framework of porous media mechanics theory and are solved numerically in a fully coupled manner. An examples dealing with a concrete dam is shown. © 2012 Springer Science+Business Media B.V.

Singh B.,CNR Institute of Neuroscience | Cree A.,Westmead Specialist Center
Spine Journal | Year: 2015

Background context Instability of the atlantoaxial spine is a recognized problem in children. Safe passage of pedicle screws at C2 poses challenges because of the proximity to the vertebral artery, size of the pedicles, and variations in the location of the foramen transversarium. Purpose The C2 translaminar technique is a useful option and its stability is comparable to that offered by C2 pedicle screws. In this follow-up from our previously published study, we wanted to verify the safety and suitability of the C2 laminar screw in the treatment of cervical instability in the pediatric population. Study design/setting We present a case series of eight pediatric patients who underwent laminar screw fixation of the axis as part of their operative procedure. Patient sample There were five girls and three boys, with a mean age of 7 years (range 2-17 years) who underwent this procedure. Surgical indications included atlantoaxial instability, atlanto-occipital disassociation, multilevel cervical instability, and high cervical stenosis. Seven patients had underlying dysplastic syndromes. Outcome measures We studied the technical feasibility of passing laminar screws at C2 in eight consecutive patients, paying attention to screw length and diameter, vascular or neurologic complications, and stability of fixation. Methods This retrospective study was funded by our institution and there was no potential conflict of interest. All patients were placed prone. The posterior aspect of the cervical spine and craniocervical junction were exposed subperiosteally. We report our modification of the Wright technique, which allowed us to safely pass 3.5-mm screws into both laminae of the second cervical vertebra. Results A total of 15 laminar screws were passed at C2. The follow-up period ranged from 1 to 24 months (mean 8 months). There were no vascular or neurologic complications, no infection, and no instances of hardware failure either by lamina fracture or screw pullout. All patients maintained stable constructs on imaging studies at the last follow-up evaluation. Conclusion Children as young as 2 years can undergo safe and rigid fixation of the axis. The technique is especially valuable in patients with dysplastic bone and distorted anatomy where more traditional methods of C2 fixation cannot be safely used. To our knowledge, this is the largest reported series of C2 laminar screw fixation in a pediatric population. © 2015 Published by Elsevier Inc. All rights reserved.

Drago I.,University of Padua | Pizzo P.,University of Padua | Pozzan T.,University of Padua | Pozzan T.,CNR Institute of Neuroscience | Pozzan T.,Venetian Institute of Molecular Medicine
EMBO Journal | Year: 2011

Mitochondrial Ca 2+ uptake and release play a fundamental role in the control of different physiological processes, such as cytoplasmic Ca 2+ signalling, ATP production and hormone metabolism, while dysregulation of mitochondrial Ca 2+ handling triggers the cascade of events that lead to cell death. The basic mechanisms of mitochondrial Ca 2+ homeostasis have been firmly established for decades, but the molecular identities of the channels and transporters responsible for Ca 2+ uptake and release have remained mysterious until very recently. Here, we briefly review the main findings that have led to our present understanding of mitochondrial Ca 2+ homeostasis and its integration in cell physiology. We will then discuss the recent work that has unravelled the biochemical identity of three key molecules: NCLX, the mitochondrial Na +/Ca 2+ antiporter, MCU, the pore-forming subunit of the mitochondrial Ca 2+ uptake channel, and MICU1, one of its regulatory subunits. © 2011 European Molecular Biology Organization | All Rights Reserved.

Ngai K.L.,University of Pisa | Prevosto D.,CNR Institute of Neuroscience | Grassia L.,The Second University of Naples
Journal of Polymer Science, Part B: Polymer Physics | Year: 2013

The nanobubble inflation method is the only experimental technique that can measure the viscoelastic creep compliance of unsupported ultrathin films of polymers over the glass-rubber transition zone as well as the dependence of the glass transition temperature (Tg) on film thickness. Sizeable reduction of Tg was observed in polystyrene (PS) and bisphenol A polycarbonate by the shift of the creep compliance to shorter times. The dependence of Tg on film thickness is consistent with the published data of free-standing PS ultrathin films. However, accompanying the shift of the compliance to shorter times, a decrease in the rubbery plateau compliance is observed. The decrease becomes more dramatic in thinner films and at lower temperatures. This anomalous viscoelastic behavior was also observed in poly(vinyl acetate) and poly (n-butyl methacrylate), but with large variation in the change of either the Tg or the plateau compliance. By now, well established in bulk polymers is the presence of three different viscoelastic mechanisms in the glass-rubber transition zone, namely, the Rouse modes, the sub-Rouse modes, and the segmental α-relaxation. Based on the thermorheological complexity of the three mechanisms, the viscoelastic anomaly observed in ultrathin polymer films and its dependence on chemical structure are explained in the framework of the Coupling Model. © 2012 Wiley Periodicals, Inc.

Schiaffino S.,University of Padua | Schiaffino S.,Venetian Institute of Molecular Medicine | Schiaffino S.,CNR Institute of Neuroscience
Acta Physiologica | Year: 2010

Muscle performance is in part dictated by muscle fibre composition and a precise understanding of the genetic and acquired factors that determine the fibre type profile is important in sport science, but is also relevant to neuromuscular diseases and to metabolic diseases, such as type 2 diabetes. The dissection of the signalling pathways that determine or modulate the muscle fibre phenotype has thus potential clinical significance. In this brief review, I examine the evolution of the notion of muscle fibre types, discuss some aspects related to species differences, point at problems in the interpretation of transgenic and knockout models and show how in vivo transfection can be used to identify regulatory factors involved in fibre type diversification, focusing on the calcineurin-nuclear factor of activated T cells (NFAT) pathway. © 2010 Scandinavian Physiological Society.

Contreras L.,University of Padua | Drago I.,University of Padua | Zampese E.,University of Padua | Pozzan T.,CNR Institute of Neuroscience
Biochimica et Biophysica Acta - Bioenergetics | Year: 2010

Calcium handling by mitochondria is a key feature in cell life. It is involved in energy production for cell activity, in buffering and shaping cytosolic calcium rises and also in determining cell fate by triggering or preventing apoptosis. Both mitochondria and the mechanisms involved in the control of calcium homeostasis have been extensively studied, but they still provide researchers with long-standing or even new challenges. Technical improvements in the tools employed for the investigation of calcium dynamics have been-and are still-opening new perspectives in this field, and more prominently for mitochondria. In this review we present a state-of-the-art toolkit for calcium measurements, with major emphasis on the advantages of genetically encoded indicators. These indicators can be efficiently and selectively targeted to specific cellular sub-compartments, allowing previously unavailable high-definition calcium dynamic studies. We also summarize the main features of cellular and, in more detail, mitochondrial calcium handling, especially focusing on the latest breakthroughs in the field, such as the recent direct characterization of the calcium microdomains that occur on the mitochondrial surface upon cellular stimulation. Additionally, we provide a major example of the key role played by calcium in patho-physiology by briefly describing the extensively reported-albeit highly controversial-alterations of calcium homeostasis in Alzheimer's disease, casting lights on the possible alterations in mitochondrial calcium handling in this pathology. © 2010 Elsevier B.V.

Pucci A.,University of Pisa | Pucci A.,CNR Institute of Neuroscience | Pucci A.,Consortium for Science and Technology of Materials | Ruggeri G.,University of Pisa | Ruggeri G.,Consortium for Science and Technology of Materials
Journal of Materials Chemistry | Year: 2011

Mechanochromic polymer blends, i.e. polymer blends characterised by optical responsiveness to mechanical stimuli, have evoked major interest and experienced significant progress in recent years. Various examples are reported of chromogenic materials composed of a functional dye covalently linked to the polymer chains or physically dispersed in the continuous macromolecular matrix, the latter appears to be a more sustainable route for the industrial scale-up of these materials. This feature article examines the properties and performances of various mechanochromic materials prepared by using different thermoplastic polymers with non-covalently incorporated aggregachromic dyes. More specifically, the general mechanism underlying the optical phenomenon is introduced and the different approaches used to obtain chromogenic materials are presented and discussed considering both dye features and polymer characteristics. The combination of the properties of the blend components can often result in drastic differences in the material chromogenic responsiveness. The article concludes commenting and discussing the application of these kind of polymer devices as a new type of advanced materials and the perspective thereof. © 2011 The Royal Society of Chemistry.

Principi A.,CNR Institute of Neuroscience | Asgari R.,Institute for Research in Fundamental Sciences | Polini M.,CNR Institute of Neuroscience
Solid State Communications | Year: 2011

We demonstrate that single-layer graphene in the presence of a metal gate displays a gapless collective (plasmon) mode that has a linear dispersion at long wavelengths. We calculate exactly the acoustic-plasmon group velocity at the level of the random phase approximation and carry out microscopic calculations of the one-body spectral function of such systems. Despite screening exerted by the metal, we find that graphene's quasiparticle spectrum displays a very rich structure characterized by composite hole-acoustic plasmon satellite bands (that we term for brevity "soundarons"), which can be observed by e.g. angle-resolved photoemission spectroscopy. © 2011 Elsevier Inc. All rights reserved.

Belluzzi E.,University of Padua | Greggio E.,University of Padua | Piccoli G.,CNR Institute of Neuroscience
Biochemical Society Transactions | Year: 2012

PD (Parkinson's disease) is a common neurodegenerative disease clinically characterized by bradykinesia, rigidity and resting tremor. Recent studies have proposed that synaptic dysfunction, implicated in numerous studies of animal models of PD,might be a key factor in PD. The molecular defects that lead to PD progression might be hidden at the presynaptic neuron: in fact accumulating evidence has shown that the majority of the genes linked to PD play a critical role at the presynaptic site. In the present paper,we focus on the presynaptic function of LRRK2 (leucine-rich repeat kinase 2), a protein that mutated represents the main genetic cause of familial PD described to date. Neurotransmission relies on proper presynaptic vesicle trafficking; defects in this process, variation in dopamine flow and alteration of presynaptic plasticity have been reported in several animal models of LRRK2 mutations. Furthermore, impaired dopamine turnover has been described in presymptomatic LRRK2 PD patients. Thus, given the pathological events occurring at the synapses of PD patients, the presynaptic site may represent a promising target for early diagnostic therapeutic intervention. ©The Authors Journal compilation ©2012 Biochemical Society.