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Conti C.,CNR Institute of Neuroscience | Delre E.,University of LAquila
Physical Review Letters | Year: 2010

We investigate theoretically, numerically, and experimentally nonlinear optical waves in an absorbing out-of-equilibrium colloidal material at the gelification transition. At a sufficiently high optical intensity, absorption is frustrated and light propagates into the medium. The process is mediated by the formation of a matter-shock wave due to optically induced thermodiffusion and largely resembles the mechanism of hydrodynamical supercavitation, as it is accompanied by a dynamic phase-transition region between the beam and the absorbing material. © 2010 The American Physical Society.

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.

Sorrentino A.,CNR Institute of Neuroscience
Archives of Computational Methods in Engineering | Year: 2010

Magnetoencephalography (MEG) is a powerful technique for brain functional studies, which allows investigation of the neural dynamics on a millisecond time-scale. The localization of the neural sources from the measured magnetic fields, based on the solution of an inverse problem, is complicated by several issues. First, the problem is ill-posed: There are infinitely many current distributions explaining a given measurement equally well. Second, the amount of noise on the data is very high, and the main source of noise is the brain itself. Third, the problem is dynamical because the temporal resolution of the data is of the same order of the temporal scale of the neural dynamics. In the last two decades, many different methods have been proposed and applied for solving the MEG inverse problem; however, the search for a reliable yet general and automatic approach to MEG source modeling is still open. Recently we have worked at applying a new class of algorithms, known as particle filters, to the MEG problem. Here we attempt a review of these methods and show encouraging results obtained on both synthetic and experimental MEG data. © 2010 CIMNE, Barcelona, Spain.

Sgheri L.,CNR Institute of Neuroscience
Inverse Problems | Year: 2010

We study the inverse problem of determining the conformational freedom of two protein domains from residual dipolar coupling (RDC) measurements. For each paramagnetic ion attached to one of the domains we obtain a magnetic susceptibility tensor | χ from the RDC of couples of atoms of that domain, and a mean paramagnetic susceptibility tensor | χ from the RDC of couples of atoms of the other domain. The latter is an integral average of rotations of χ which depends on the conformational freedom of the two domains. In this paper we consider the case when we have data from paramagnetic ions attached separately to each of the domains. We prove that in this case not all the elements of χ and χ are independent. We derive the mathematical equations for the compatibility of the measurements and show how these relations can be used in the presence of noisy data to determine a compatible set of x and x with an unconstrained minimization. If available, information about the shape of the noise can be included in the target function. We show that in this case the compatible set obtained has a reduced error with respect to the noisy data. © 2010 IOP Publishing Ltd.

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.

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.

Mathematical models of the excitatory synapse are furnishing valuable information about the synaptic response. Based on Brownian-diffusion of glutamate molecules, a synapse model was utilized to investigate the synaptic response on a femto-second time scale by the use of a parallel computer. In particular, the presence of fibrils crossing the synaptic cleft was simulated, which could have a role in shaping the brain activity. To this aim the model of synapse was modified by considering trans-synaptic filaments with diameters ranging from 7. nm to 3. nm, disposed on a grid with spacing of 14. nm or 8. nm. The simulation demonstrated that the presence of filaments induced an increase in the synaptic response, most likely linked to an increment in the probability of encounter between glutamate molecules and receptors. The increase was small - from 5 to 20%, but metabolic and functional considerations provide substantive hints about the importance of these small changes for brain activity. Moreover, it was shown that the presence of filaments made more stable the response of the synapse to random variations of pre-synaptic elements. Originated by these computational results, some inferences about the biological bases of mind diseases such as autism, mental retardation and schizophrenia, are reported in the Discussion. © 2010 Elsevier Ireland Ltd.

De Canditiis D.,CNR Institute of Neuroscience
Computational Statistics and Data Analysis | Year: 2014

In non-parametric regression analysis the advantage of frames with respect to classical orthonormal bases is that they can furnish an efficient representation of a more broad class of functions. For example, fast oscillating functions as audio, speech, sonar, radar, EEG and stock market are much more well represented by a frame, with similar oscillating characteristic, than by a classical orthonormal basis. In this respect, a new frame based shrinkage estimator is derived as the Empirical Regularized version of the optimal Shrinkage estimator generalized to the frame operator. An analytic expression of it is furnished leading to an efficient implementation. Results on standard and real test functions are shown. © 2014 Elsevier B.V. All rights reserved.

Pio G.,University of Bari | Malerba D.,University of Bari | D'Elia D.,CNR Institute of Neuroscience | Ceci M.,University of Bari
BMC Bioinformatics | Year: 2014

Background: MicroRNAs (miRNAs) are small non-coding RNAs which play a key role in the post-transcriptional regulation of many genes. Elucidating miRNA-regulated gene networks is crucial for the understanding of mechanisms and functions of miRNAs in many biological processes, such as cell proliferation, development, differentiation and cell homeostasis, as well as in many types of human tumors. To this aim, we have recently presented the biclustering method HOCCLUS2, for the discovery of miRNA regulatory networks. Experiments on predicted interactions revealed that the statistical and biological consistency of the obtained networks is negatively affected by the poor reliability of the output of miRNA target prediction algorithms. Recently, some learning approaches have been proposed to learn to combine the outputs of distinct prediction algorithms and improve their accuracy. However, the application of classical supervised learning algorithms presents two challenges: i) the presence of only positive examples in datasets of experimentally verified interactions and ii) unbalanced number of labeled and unlabeled examples. Results: We present a learning algorithm that learns to combine the score returned by several prediction algorithms, by exploiting information conveyed by (only positively labeled/) validated and unlabeled examples of interactions. To face the two related challenges, we resort to a semi-supervised ensemble learning setting. Results obtained using miRTarBase as the set of labeled (positive) interactions and mirDIP as the set of unlabeled interactions show a significant improvement, over competitive approaches, in the quality of the predictions. This solution also improves the effectiveness of HOCCLUS2 in discovering biologically realistic miRNA:mRNA regulatory networks from large-scale prediction data. Using the miR-17-92 gene cluster family as a reference system and comparing results with previous experiments, we find a large increase in the number of significantly enriched biclusters in pathways, consistent with miR-17-92 functions. Conclusion: The proposed approach proves to be fundamental for the computational discovery of miRNA regulatory networks from large-scale predictions. This paves the way to the systematic application of HOCCLUS2 for a comprehensive reconstruction of all the possible multiple interactions established by miRNAs in regulating the expression of gene networks, which would be otherwise impossible to reconstruct by considering only experimentally validated interactions. © 2014 Pio et al.; licensee BioMed Central Ltd.

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.

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.

Rontani M.,CNR Institute of Neuroscience
Physical Review B - Condensed Matter and Materials Physics | Year: 2014

We show theoretically that an undoped carbon nanotube might be an excitonic insulator - the long-sought phase of matter proposed by Keldysh, Kohn, and others fifty years ago. We predict that the condensation of triplet excitons, driven by intervalley exchange interaction, spontaneously occurs at equilibrium if the tube radius is sufficiently small. The signatures of exciton condensation are its sizable contributions to both the energy gap and the magnetic moment per electron. The increase of the gap might have already been measured, albeit with a different explanation [V. V. Deshpande, B. Chandra, R. Caldwell, D. S. Novikov, J. Hone, and M. Bockrath, Science 323, 106 (2009)SCIEAS0036-807510.1126/science.1165799]. The enhancement of the quasiparticle magnetic moment is a pair-breaking effect that counteracts the weak paramagnetism of the ground-state condensate of excitons. This property could rationalize the anomalous magnitude of magnetic moments recently observed in different devices close to charge neutrality. © 2014 American Physical Society.

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.

Condliffe S.B.,University of Otago | Matteoli M.,CNR Institute of Neuroscience
Channels | Year: 2011

SNAP-25 forms part of the SNARE core complex that mediates membrane fusion. Biochemical and electrophysiological evidence supports an accessory role for SNAP-25 in interacting with voltage-gated calcium channels (VGCCs) to modulate channel activity. We recently reported that endogenous SNAP-25 negatively regulates VGCC activity in glutamatergic neurons from rat hippocampal cultures by shifting the voltage-dependence of inactivation of the predominant P/Q-type channel current in these cells. In the present study, we extend these findings by investigating the effect that manipulating endogenous SNAP-25 expression has on the inactivation kinetics of VGCC current in both glutamatergic and GABAergic cells recorded from 9-13 DIV cultures. Silencing SNAP-25 in glutamatergic neurons significantly slowed the inactivation rate of P/Q-type VGCC current whereas alterations in SNAP-25 expression did not alter inactivation rates in GABAergic neurons. These results indicate that endogenous SNAP-25 plays an important role in P/Q-type channel regulation in glutamatergic neurons. © 2011 Landes Bioscience.

Straccia U.,CNR Institute of Neuroscience
Proceedings of The International Symposium on Multiple-Valued Logic | Year: 2010

We outline DL-Media, an ontology mediated multimedia information retrieval system, which combines logic-based retrieval with multimedia feature-based similarity retrieval. An ontology layer is used to define (in terms of a fuzzy description logic) the relevant abstract concepts and relations of the application domain, while a content-based multimedia retrieval system is used for feature-based retrieval. © 2010 IEEE.

Sternativo P.,Polytechnic University of Turin | Dolcini F.,Polytechnic University of Turin | Dolcini F.,CNR Institute of Neuroscience
Physical Review B - Condensed Matter and Materials Physics | Year: 2014

When a constriction is realized in a 2D quantum spin Hall system, electron tunneling between helical edge states occurs via two types of channels allowed by time-reversal symmetry, namely spin-preserving (p) and spin-flipping (f) tunneling processes. Determining and controlling the effects of these two channels is crucial to the application of helical edge states in spintronics. We show that, despite that the Hamiltonian terms describing these two processes do not commute, the scattering matrix entries of the related 4-terminal setup always factorize into products of p-term and f-term contributions. Such factorization provides an operative way to determine the transmission coefficients Tp and Tf related to each of the two processes, via transconductance measurements. Furthermore, these transmission coefficients are also found to be controlled independently by a suitable combination of two gate voltages applied across the junction. This result holds for an arbitrary profile of the tunneling amplitudes, including disorder in the tunnel region, enabling us to discuss the effect of the finite length of the tunnel junction, and the space modulation of both magnitude and phase of the tunneling amplitudes. © 2014 American Physical Society.

Lomascolo M.,CNR Institute of Neuroscience | Colangelo G.,University of Salento | Milanese M.,University of Salento | De Risi A.,University of Salento
Renewable and Sustainable Energy Reviews | Year: 2015

An analytical overview of experimental results about the heat transfer capabilities of nanofluids is presented, using widely scattered available information from diverse literature sources. It is shown that, despite the large number of publications available about this issue, only few studies provide quantitative estimates on a complete set of experimental conditions so far and many studies are not coherent. Bearing in mind this problem, in this study a selection of the most valuable papers has been done, taking into account different points of view and hypotheses. Even if this work cannot be considered exhaustive of the complete literature in the field of nanofluids, it can be taken into account as a quick reference guide to have an overview of the different heat transfer phenomena in nanofluids and how the most important parameters (size, shape, concentration, materials etc.) influence the expected thermal performance of nanofluids. © 2014 Elsevier Ltd. All rights reserved.

Buitrago E.,University of Stockholm | Zani L.,CNR Institute of Neuroscience | Adolfsson H.,University of Stockholm
Applied Organometallic Chemistry | Year: 2011

Aryl alkyl-, heteroaryl alkyl- and dialkyl ketones were readily reduced to their corresponding secondary alcohols in high yields, using the commercially available and inexpensive polymeric silane polymethylhydrosiloxane (PMHS), as reducing agent. The reaction is catalyzed by an in situ-generated iron complex, conveniently generated from iron(II) acetate and the commercially available N-heterocyclic carbene (NHC) precursor IPr·HCl. © 2011 John Wiley & Sons, Ltd.

Rontani M.,CNR Institute of Neuroscience
Nature Materials | Year: 2011

A study was conducted to demonstrate that tunneling and capacitance spectroscopies were able to image the wavefunctions of electrons in atom-like solid-state systems as they were shaped by an external magnetic field. The tunneling and capacitance spectroscopies probed the electron probability density with energy and space selectivity. The researchers engaged in the study were able to identify two regimes dominated by Coulomb and magnetic confinement. The researchers also investigated the shaping effect of the field on two orbitals of the quantum-dot p-shell. Investigations also revealed that one orbital had x-like symmetry and the other y-like symmetry at zero field, reflecting the elliptical anisotropy of the dot potential.

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.

Paternostro M.,Queens University of Belfast | De Chiara G.,Autonomous University of Barcelona | Palma G.M.,CNR Institute of Neuroscience
Physical Review Letters | Year: 2010

We consider a cavity with a vibrating end mirror and coupled to a Bose-Einstein condensate. The cavity field mediates the interplay between mirror and collective oscillations of the atomic density. We study the implications of this dynamics and the possibility of an indirect diagnostic. Our predictions can be observed in a realistic setup that is central to the current quest for mesoscopic quantumness. © 2010 The American Physical Society.

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.

Duine R.A.,University Utrecht | Polini M.,CNR Institute of Neuroscience | Stoof H.T.C.,University Utrecht | Vignale G.,University of Missouri
Physical Review Letters | Year: 2010

Recent experiments have presented evidence of ferromagnetic correlations in a two-component ultracold Fermi gas with strong repulsive interactions. Motivated by these experiments we consider spin drag, i.e., frictional drag due to scattering of particles with opposite spin, in such systems. We show that when the ferromagnetic state is approached from the normal side, the spin drag relaxation rate is strongly enhanced near the critical point. We also determine the temperature dependence of the spin diffusion constant. In a trapped gas the spin drag relaxation rate determines the damping of the spin dipole mode, which therefore provides a precursor signal of the ferromagnetic phase transition that may be used to experimentally determine the proximity to the ferromagnetic phase. © 2010 The American Physical Society.

Talia D.,CNR Institute of Neuroscience
IEEE Internet Computing | Year: 2012

Cloud computing systems provide large-scale infrastructures for high-performance computing that can adapt to user and application needs. Multi-agent systems (MASs) comprise interacting agents capable of intelligent behavior. Integrating these two technologies could enable high-performance, complex systems and intelligent applications, making clouds more flexible and autonomic and providing MASs with a reliable and scalable computing infrastructure on which to execute large-scale applications. © 2006 IEEE.

Epigenetics, first described by Conrad Waddington, defines how pathways setting a specific pheno-type and heritable cellular functions are activated in a DNA independent way. Epigenetics concerns the study of genome structure and accessibility that regulates patterns of gene expression through the dynamic compaction and opening the chromatin structure. Vincent Allfrey profetically declared in 1964 that histone modifications could influence gene expression. In cancer very often cells show a profound modification of DNA methylation and mutations in chromatin regulators. These evidences provided therefore a clear link between epigenetics and neoplasia. Advanced molecular technology such as Deep-sequencing and ChIP-Seq revealed the frequent re-localization in cancer of many PTM readers such the Ac-Lys binding bromodomain. These results were important for the development of novel classes of epigenetic drugs some of which are inhibitors of histone modifyers or molecule interacting with reader domains. Since cancer imply profound changes in the epigenetic profile and in gene transcription a future challenge of molecular and chemical biology will be to develop novel epigenetic compounds able to correct the epigenetic disfunction and, possibly, coadiuvate canonical therapy in the cure of cancer.

Mugnai D.,CNR Institute of Neuroscience
Applied Optics | Year: 2011

Recently, the use of Bessel beams in evaluating the possibility of using them for a new generation of ground penetrating radar systems has been considered. Therefore, an analysis of the propagation of Bessel beams in conducting media is worthwhile. We present here an analysis of this type. Specifically, for normal incidence we analyze the propagation of a Bessel beam coming from a perfect dielectric and impinging on a conducting medium, i.e., the propagation of a Bessel beam generated by refracted inhomogeneous waves. The remarkable and unexpected result is that the incident Bessel beam does not change its shape even when propagating in the conducting medium. © 2011 Optical Society of America.

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.

Pacifico F.,CNR Institute of Neuroscience | Leonardi A.,University of Naples Federico II
Molecular and Cellular Endocrinology | Year: 2010

Thyroid cancer is the most common neoplasia of the endocrine system and accounts for approximately 1% of all newly diagnosed cancer cases. Its incidence has rapidly grown over the past few decades. Although most thyroid carcinomas are of the well-differentiated papillary histology, and respond well to treatment with surgical resection followed by radioactive iodine ablation, tumors with more aggressive phenotype, such as follicular, poorly differentiated, anaplastic, and medullary cancers, lead to almost 1500 patient deaths annually. Therefore, understanding molecular mechanisms that regulate the biology of these carcinomas could be helpful to identify new molecules acting as novel targets for therapeutic intervention.NF-κB has been recently shown to play an important role in thyroid cancer for its ability to control the proliferative and the anti-apoptotic signaling pathways of thyroid neoplastic cells. Oncogenic proteins RET/PTC, RAS and BRAF, that are involved in many aspects of thyroid carcinogenesis, can induce NF-κB activation in papillary, follicular, and medullary thyroid carcinomas, while constitutive de-regulated NF-κB activity has been found in anaplastic thyroid carcinomas. A number of NF-κB inhibitors have been demonstrated to induce anti-proliferative effects and/or massive apoptosis, especially in combination with radio- or chemo-therapy. The results obtained suggest that targeting NF-κB could be a promising strategy for advanced thyroid cancer treatment. © 2009 Elsevier Ireland Ltd.

Di Carlo M.,CNR Institute of Neuroscience
European Biophysics Journal | Year: 2010

Amyloid beta peptide (Aβ) is the major component of amyloid plaques in the brain of individuals affected by Alzheimer's disease (AD). The formation of the plaques is due to an overproduction of Aβ by APP processing, its precursor, and to its ability to convert under specific conditions from its soluble form into highly ordered fibrillar aggregates. Although neuronal degeneration occurs near the amyloid plaques, some studies have suggested that intermediates such as protofibrils or simple oligomers are also involved in AD pathogenesis and even appear to be the more dangerous species in the onset of the pathology. Further, toxic properties of aggregates of different size have been investigated and the obtained results support the hypothesis that different aggregate sizes can induce different degeneration pathways. In the present review some of the knowledge about the biochemical routes of Aβ processing and production and the relationship among Aβ and oxidative stress, metal homeostasis, inflammatory process, and cell death are summarized. Moreover, current strategies addressing both fibrillogenesis process and different Aβ altered biochemical pathways utilized for therapies are described. © 2009 European Biophysical Societies' Association.

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.

Garofalo M.,Ohio State University | Condorelli G.L.,IRCCS MultiMedica | Croce C.M.,Ohio State University | Condorelli G.,University of Naples Federico II | Condorelli G.,CNR Institute of Neuroscience
Cell Death and Differentiation | Year: 2010

Death receptors, belonging to the TNF receptor superfamily, induce apoptosis through two different pathways, one involving the effector caspases directly (type I cells or mitochondria-independent death), the other one amplifying the death signal through the mitochondrial pathway (type II cells or mitochondria-dependent death). MicroRNAs (miRNAs) are a class of small noncoding RNAs that regulate the stability or translational efficiency of targeted messenger RNAs. MiRNAs are involved in many cellular processes that are altered in cancer, such as differentiation, proliferation and apoptosis. In this review we will discuss recent findings implicating miRNAs as regulators of death receptors and pro-and antiapoptotic genes involved in programmed cell death pathways. © 2010 Macmillan Publishers Limited All rights reserved.

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.

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.

Chen X.-W.,Max Planck Institute for the Science of Light | Sandoghdar V.,Max Planck Institute for the Science of Light | Agio M.,CNR Institute of Neuroscience
Physical Review Letters | Year: 2013

We provide a general theoretical platform based on quantized radiation in absorptive and inhomogeneous media for investigating the coherent interaction of light with material structures in the immediate vicinity of quantum emitters. In the case of a very small metallic cluster, we demonstrate extreme regimes where a single emitter can either counteract or enhance particle absorption by 3 orders of magnitude. For larger structures, we show that an emitter can eliminate both scattering and absorption and cloak a plasmonic antenna. We provide physical interpretations of our results and discuss their applications in active metamaterials and quantum plasmonics. © 2013 American Physical Society.

Grillo V.,CNR Institute of Neuroscience | Grillo V.,CNR Institute of Materials for Electronics and Magnetism | Rossi F.,CNR Institute of Materials for Electronics and Magnetism
Journal of Crystal Growth | Year: 2011

Scanning TEM with a High Angle Annular Dark Field (HAADF) detector is an outstanding tool for chemical analysis; it permits to image compositional variations at atomic scale as variation in the image intensity. However in the interpretation of HAADF images the role of elastic strain and crystallographic defects are often neglected. For low index specimen orientation crystal imperfections can become very important due to the interplay of strain and channeling effects. Thanks to a recently developed channeling model, the main strain effects on the image can be predicted. An adequate description of these phenomena makes HAADF an interesting technique to complement or substitute traditional TEM characterization in many relevant materials science contexts. Examples will be shown for the case of semiconductor quantum dot, core shell nanowires and dislocations. © 2010 Elsevier B.V.

Liscidini M.,University of Pavia | Gerace D.,University of Pavia | Sanvitto D.,CNR Institute of Neuroscience | Bajoni D.,University of Pavia
Applied Physics Letters | Year: 2011

The authors report on a theoretical investigation of guided polariton states arising from the strong coupling between quantum-well excitons and a Bloch surface wave confined at the interface between a uniform dielectric medium and a Bragg mirror. It is shown that the exciton-photon coupling is almost doubled as compared to a similar structure made in a conventional planar microcavity. It is also shown that, by simple engineering of the sample surface with silicon oxide deposition, one can efficiently produce one-dimensional polaritons propagating within the structure with extremely low losses. The latter result evidences the usefulness of Bloch surface waves as a key component for the realization of "polaritonic integrated circuits." © 2011 American Institute of Physics.

Ceriani F.,University of Padua | Mammano F.,University of Padua | Mammano F.,CNR Institute of Neuroscience
Cell Communication and Signaling | Year: 2013

Background: A variety of mechanisms that govern connexin channel gating and permeability regulate coupling in gap junction networks. Mutations in connexin genes have been linked to several pathologies, including cardiovascular anomalies, peripheral neuropathy, skin disorders, cataracts and deafness. Gap junction coupling and its patho-physiological alterations are commonly assayed by microinjection experiments with fluorescent tracers, which typically require several minutes to allow dye transfer to a limited number of cells. Comparable or longer time intervals are required by fluorescence recovery after photobleaching experiments. Paired electrophysiological recordings have excellent time resolution but provide extremely limited spatial information regarding network connectivity. Results: Here, we developed a rapid and sensitive method to assay gap junction communication using a combination of single cell electrophysiology, large-scale optical recordings and a digital phase-sensitive detector to extract signals with a known frequency from Vf2.1.Cl, a novel fluorescent sensor of plasma membrane potential. Tests performed in HeLa cell cultures confirmed that suitably encoded Vf2.1.Cl signals remained confined within the network of cells visibly interconnected by fluorescently tagged gap junction channels. We used this method to visualize instantly intercellular connectivity over the whole field of view (hundreds of cells) in cochlear organotypic cultures from postnatal mice. A simple resistive network model reproduced accurately the spatial dependence of the electrical signals throughout the cellular network. Our data suggest that each pair of cochlear non-sensory cells of the lesser epithelial ridge is coupled by ∼1500 gap junction channels, on average. Junctional conductance was reduced by 14% in cochlear cultures harboring the T5M mutation of connexin30, which induces a moderate hearing loss in connexin30T5M/T5M knock-in mice, and by 91% in cultures from connexin30-/- mice, which are profoundly deaf. Conclusions: Our methodology allows greater sensitivity (defined as the minimum magnitude of input signal required to produce a specified output signal having a specified signal-to-noise ratio) and better time resolution compared to classical tracer-based techniques. It permitted us to dynamically visualize intercellular connectivity down to the 10th order in non-sensory cell networks of the developing cochlea. We believe that our approach is of general interest and can be seamlessly extended to a variety of biological systems, as well as to other connexin-related disease conditions. © 2013 Ceriani and Mammano; licensee BioMed Central Ltd.

Trotta E.,CNR Institute of Neuroscience
Nucleic Acids Research | Year: 2013

Codons that code for the same amino acid are often used with unequal frequencies. This phenomenon is termed codon bias. Here, we report a computational analysis of codon bias in yeast using experimental and theoretical genome-wide data. We show that the most used codons in highly expressed genes can be predicted by mRNA structural data and that the codon choice at each synonymous site within an mRNA is not random with respect to the local secondary structure. Because we also found that the folding stability of intron sequences is strongly correlated with codon bias and mRNA level, our results suggest that codon bias is linked to mRNA folding structure through a mechanism that, at least partially, operates before pre-mRNA splicing. Consistent with this, we report evidence supporting the adaptation of the tRNA pool to the codon profile of the most expressed genes rather than vice versa. We show that the correlation of codon usage with the gene expression level also includes the stop codons that are normally not decoded by aminoacyl-tRNAs. The results reported here are consistent with a role for transcriptional forces in driving codon usage bias via a mechanism that improves gene expression by optimizing mRNA folding structures. © The Author(s) 2013. Published by Oxford University Press.

Ciattoni A.,CNR Institute of Neuroscience | Rizza C.,University of LAquila | Palange E.,University of LAquila
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011

We theoretically propose and numerically investigate an active plasmonic device made up of a nonlinear ε-near-zero metamaterial slab of thickness smaller than 100 nm lying on a linear ε-near-zero metamaterial substrate. We predict that in free-space coupling configuration the system operating at low intensity displays plasmon mediated hysteresis behavior. The phase difference between the reflected and the incident optical waves turns out to be multivalued and dependent on the history of the excitation process. Such an hysteresis behavior allows the proposed system to be regarded as a memory device whose state is accessible by measuring either the mentioned phase difference or the power, which is multivalued as well, carried by the nonlinear plasmon wave. Since multiple plasmon powers comprise both positive and negative values, the device also operates as a switch of the plasmon power direction at each jump along an hysteresis loop. © 2011 American Physical Society.

Rizza C.,University of LAquila | Ciattoni A.,CNR Institute of Neuroscience | Ciattoni A.,University of LAquila | Palange E.,University of LAquila
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011

We investigate analytically transverse-magnetic spatial bright solitons, as exact solutions of Maxwell's equations, propagating through nonlinear metamaterials whose linear dielectric permittivity is very close to zero and whose effective nonlinear Kerr parameters can be tailored to achieve values not available in standard materials. Exploiting the fact that, in the medium considered, linear and nonlinear polarization can be comparable at feasible and realistic optical intensities, we identify two self-trapping mechanisms able to support two-peaked and flat-top solitons, respectively. Specifically, these two mechanisms are based on the occurrence of critical points at which the effective nonlinear permittivity vanishes, the two mechanisms differing in the way the compensation between linear and nonlinear polarization is achieved through the nonstandard values of the nonlinear parameters. © 2011 American Physical Society.

Troiani F.,CNR Institute of Neuroscience
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2011

We investigate the entanglement properties of finite spin rings, with noncollinear Ising interaction between nearest neighbors. The orientations of the Ising axes are determined either by the spin position within the ring (model A) or by the direction of the bond (model B). In both cases, the considered spin Hamiltonians have a point-group symmetry instead of the translation invariance that characterizes spin rings with collinear Ising interaction. The ground state of these models exhibit remarkable entanglement properties, resembling Greenberger-Horne-Zeilinger (GHZ)-like states in the absence of an applied magnetic field (model B). Besides, the application of a homogeneous magnetic field allows to modify qualitatively the character of the ground-state entanglement, switching from multipartite to pairwise quantum correlations (both models A and B). © 2011 American Physical Society.

Zoppi L.,University of Zurich | Ferretti A.,CNR Institute of Neuroscience | Baldridge K.K.,University of Zurich
Journal of Chemical Theory and Computation | Year: 2013

First principles techniques are used to investigate the structure, linear polarizability, and field-oriented property trends of the series of bowl shaped polynuclear aromatic hydrocarbon fragments, C20H10, C 30H10, C40H10, and C 50H10. Such structures represent a sequence of minimalistic, capped bucky tube units based on the corannulene molecule, with interesting technological promise imparted by their curvature. Specific issues associated with how the intrinsic dipole and static linear polarizability influences the orientation of these structures in the presence of an external electric field are addressed and shown to correlate well with a simple analytical model. At moderate electric fields, the induced dipoles become comparable and even larger than the intrinsic dipoles due to the large in-plane polarizabilities in these systems. This generates a nontrivial and field dependent orientation of the molecule that can be exploited, for example, to induce switching behavior within molecular nanojunctions. © 2013 American Chemical Society.

Anders J.,University College London | Giovannetti V.,CNR Institute of Neuroscience
New Journal of Physics | Year: 2013

We define thermodynamic configurations and identify two primitives of discrete quantum processes between configurations for which heat and work can be defined in a natural way. This allows us to uncover a general second law for any discrete trajectory that consists of a sequence of these primitives, linking both equilibrium and non-equilibrium configurations. Moreover, in the limit of a discrete trajectory that passes through an infinite number of configurations, i.e. in the reversible limit, we recover the saturation of the second law. Finally, we show that for a discrete Carnot cycle operating between four configurations one recovers Carnot's thermal efficiency. © IOP Publishing and Deutsche Physikalische Gesellschaft.

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.

Magagnotti N.,University of Bologna | Spinelli R.,CNR Institute of Neuroscience
Small-scale Forestry | Year: 2012

The authors conducted three comparative tests, to determine if the replacement of steel cable with synthetic rope may allow reducing the physiological workload of forest operators assigned to log winching tasks. The tests were conducted in Northern Italy, on the Alpine mountain and involved 7 volunteer subjects. The physiological workload was determined by measuring the operator's heart rate upon completion of every task, using heart-rate monitors. Test one was conducted under simplified, controlled conditions and detected a statistically significant reduction of relative heart rate when carrying synthetic rope, as compared to steel cable. However, tests two and three were performed under real operational conditions, and were inconclusive. Real operational conditions are characterized by the interaction of many factors, which may confound the results of the tests, or offset the benefits potentially obtained with the introduction of synthetic rope. Nevertheless, the introduction of synthetic rope offers the benefit of easier handling, which was very much appreciated by all test subjects. © 2011 Steve Harrison, John Herbohn.

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.

Corni S.,CNR Institute of Neuroscience | Hnilova M.,University of Washington | Tamerler C.,University of Washington | Sarikaya M.,University of Washington
Journal of Physical Chemistry C | Year: 2013

Genetically engineered solid binding peptides, because of their unique affinity and specificity for solid materials, represent a promising molecular toolbox for nanoscience and nanotechnology. Despite their potential, the physicochemical determinants of their high affinity for surfaces remain, in most cases, poorly understood. Here we present experimental data and classical atomistic molecular dynamics simulations for two gold binding dodecapeptides (AuBP1 and AuBP2, Hnilova, M. et al. Langmuir 2008, 24, 12440) and a control peptide that does not bind to gold, to unravel the key microscopic differences among them. In particular, by means of extensive sampling via replica exchange simulations, we show here that the conformational ensemble of the three peptides in solution and on the gold surface can be examined, and that the role played by their different conformational flexibility can be analyzed. We found, specifically, that AuBP1 and AuBP2 are much more flexible than the control peptide, which allows all the potential Au-binding amino acids present in these AuBPs to concurrently bind to the gold surface. On the contrary, the potential Au-binding amino acids in the rigid control peptide cannot contact the surface all at the same time, hampering the overall binding. The role of conformational flexibility has been also analyzed in terms of the configurational entropy of the free and adsorbed peptides. Such analysis suggests a possible route to improve upon current flexible gold binding peptides. © 2013 American Chemical Society.

Ciszak M.,CNR Institute of Neuroscience
Physica A: Statistical Mechanics and its Applications | Year: 2010

At an optimal value of the noise intensity, the maximum variability in rebound burst durations is observed and referred to as a response stochastic incoherence. A general mechanism underlying this phenomenon is given, being different from those reported so far in excitable systems. It is shown to be determined by (i) the monotonic reduction of the hysteresis responsible for bursting caused by noise and consequent transformation of responses from rebound bursts to single spikes, and (ii) a symmetry breaking in distributions of burst durations caused by the existence of the minimum response length. The phenomenon is studied numerically in a Morris-Lecar model for neurons and its mechanism is explained with the use of canonical models describing hard excitation states. © 2010 Elsevier B.V. All rights reserved.

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.

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.

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.

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.

Alava M.J.,Aalto University | Laurson L.,Aalto University | Zapperi S.,CNR Institute of Neuroscience
European Physical Journal: Special Topics | Year: 2014

Plastic deformation is a paradigmatic problem of multiscale materials modelling with relevant processes ranging from the atomistic scale up to macroscopic scales where deformation is treated by continuum mechanics. Recent experiments, investigating deformation fluctuations under conditions where plastic deformation was expected to occur in a smooth and stable manner, demonstrate that deformation is spatially heterogeneous and temporally intermittent, not only on atomic scales, where spatial heterogeneity is expected, but also on mesoscopic scales where plastic fluctuations involve collective events of widely different amplitudes. Evidence for crackling noise in plastic deformation comes from acoustic emission measurements and from deformation of micron-scale samples both in crystalline and amorphous materials. Here we provide a detailed account of our current understanding of crackling noise in crystal and amorphous plasticity stemming from experiments, computational models and scaling theories. We focus our attention on the scaling properties of plastic strain bursts and their interpretation in terms of non-equilibrium critical phenomena. © 2014, EDP Sciences and Springer.

Bobba A.,CNR Institute of Biomembrane and Bioenergetics | Amadoro G.,CNR Institute of Neuroscience | Valenti D.,CNR Institute of Biomembrane and Bioenergetics | Corsetti V.,European Brain Research Institute EBRI | And 2 more authors.
Mitochondrion | Year: 2013

Here we investigate the effect of β-amyloid on mitochondrial respiratory function, i.e.mitochondrial oxygen consumption and membrane potential generation as well as the individual activities of both the mitochondrial Complexes I-IV, that compose mitochondrial electron transport chain, and the ATP synthase, by using homogenate from cerebellar granule cells, treated with low concentrations of β-amyloid, and Alzheimer synaptic-enriched brain samples. We found that β-amyloid caused both a selective defect in Complex I activity associated with an increase (5 fold) of intracellular reactive oxygen species and an impairment of Complex IV likely due to membrane lipid peroxidation. In addition, a 130% increase of the GSSG/GSH ratio was measured in Alzheimer brains with respect to age-matched controls. Knowing the mechanisms of action of β-amyloid could allow to mitigate or even to interrupt the toxic cascade that leads a cell to death. The results of this study represent an important innovation because they offer the possibility to act at mitochondrial level and on specific sites to protect cells, for example by preventing the interaction of β-amyloid with the identified targets, by stabilizing or by restoring mitochondrial function or by interfering with the energy metabolism. © 2013 Elsevier B.V. and Mitochondria Research Society.

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.

Criscuoli A.,CNR Institute of Neuroscience
Chemical Engineering Research and Design | Year: 2016

In this work, the integration of two Membrane Distillation (MD) configurations was investigated as possible means to reduce the specific thermal energy consumption. Tests of Direct Contact Membrane Distillation (DCMD) and Air Gap Membrane Distillation (AGMD) were carried out on 40 cm2 lab-scale modules equipped with a commercial flat polypropylene membrane of 0.2 μm, by sending distilled water as feed. The performance of integrated schemes with the feed exiting from the DCMD module sent as coolant stream in the AGMD module - where it is heated by the permeating vapor, before being recycled back to the DCMD unit - was analyzed. When compared to the single DCMD units, the integrated DCMD-AGMD systems led to lower specific thermal energy consumption, as well as higher Gained Output Ratio (GOR) and permeate production. © 2016 Institution of Chemical Engineers.

Vergari F.,CNR Institute of Neuroscience
Advances in Experimental Medicine and Biology | Year: 2010

Companies in the food industry have high expectations for food products that meet the consumers' demand for a healthy life style. In this context Functional Food plays a specific role. These foods are not intended only to satisfy hunger and provide the necessary human nutrients, but also to prevent nutrition-related diseases and increase the physical and mental well-being of their consumer. Among participants in space science and missions, recognition of nutraceuticals and dietary supplements is growing for their potential in reducing health risks and to improve health quality and eating habits during long-term flights and missions. In 2008 the entire functional foods market was worth over an estimated US$80 billion, with the US holding a majority share in the nutraceuticals market (35%) followed by Japan (25%) and with the ever-growing European market, currently estimated at US$8 billion. India and China are the two major countries known for their production of traditional functional food products and nutraceuticals, but other South-East Asian countries and Gulf nations are developing potential markets. © 2010 Landes Bioscience and Springer Science+Business Media, LLC.

De Falco S.,CNR Institute of Neuroscience
Experimental and Molecular Medicine | Year: 2012

Angiogenesis is a complex biological phenomenon crucial for a correct embryonic development and for post-natal growth. In adult life, it is a tightly regulated process confined to the uterus and ovary during the different phases of the menstrual cycle and to the heart and skeletal muscles after prolonged and sustained physical exercise. Conversly, angiogenesis is one of the major pathological changes associated with several complex diseases like cancer, atherosclerosis, arthritis, diabetic retinopathy and age-related macular degeneration. Among the several molecular players involved in angiogenesis, some members of VEGF family, VEGF-A, VEGF-B and placenta growth factor (PlGF), and the related receptors VEGF receptor 1 (VEGFR-1, also known as Flt-1) and VEGF receptor 2 (VEGFR-2, also known as Flk-1 in mice and KDR in human) have a decisive role. In this review, we describe the discovery and molecular characteristics of PlGF, and discuss the biological role of this growth factor in physiological and pathological conditions.

Maggi S.,CNR Institute of Neuroscience
Expert Review of Vaccines | Year: 2010

The aging process in humans is associated with a decrease in immune function (immunosenescence) and an increase in comorbid disorders. When combined with environmental factors this can lead to an increased risk and severity of infectious diseases. Diseases in older adults (≥70 years) tend to be more severe and have a greater impact on health outcomes such as morbidity, disability, quality of life and mortality. However, some of the more common infections such as influenza and pneumococcal infection are vaccine preventable, but the uptake of such preventive strategies in adults has been poor. In this review some of the key clinical findings supporting the benefits of adult immunization are highlighted. Vaccination of the adult population needs to be a key component of a healthy aging strategy, since there is already convincing evidence that this approach can have an important impact on morbidity, mortality and quality of life. © 2010 Expert Reviews Ltd.

Sanna D.,CNR Institute of Neuroscience | Micera G.,University of Sassari | Garribba E.,University of Sassari
Inorganic Chemistry | Year: 2011

Complexation of VO 2+ ion with the most abundant class of human immunoglobulins, immunoglobulin G (IgG), was studied using EPR spectroscopy. Differently from the data in the literature which report no interaction of IgG with vanadium, in the binary system VO 2+/IgG at least three sites with comparable strength were revealed. These sites, named 1, 2, and 3, seem to be not specific, and the most probable candidates for metal ion coordination are histidine-N, aspartate-O or glutamate-O, and serinate-O or threoninate-O. The mean value for the association constant of (VO) xIgG, with x = 3-4, is log β = 10.3 ± 1.0. Examination of the ternary systems formed by VO 2+ with IgG and human serumtransferrin (hTf) and human serum albumin (HSA) allows one to find that the order of complexing strength is hTf » HSA ≈ IgG. The behavior of the ternary systems with IgG and one insulin-enhancing agent, like [VO(6-mepic) 2], cis-[VO(pic) 2(H 2O)], [VO(acac)2], and [VO(dhp) 2], where 6-mepic, pic, acac, and dhp indicate the deprotonated forms of 6-methylpicolinic and picolinic acids, acetylacetone, and 1,2-dimethyl-3-hydroxy-4(1H)- pyridinone, is very similar to the corresponding systems with albumin. In particular, at the physiological pH value, VO(6-mepic)(IgG)(OH), cis- VO(pic) 2(IgG), and cis-VO(dhp) 2(IgG) are formed. In such species, IgG coordinates nonspecifically VO 2+ through an imidazole- Nbelonging to a histidine residue exposed on the protein surface. For cis-VO(dhp) 2(IgG), log β is 25.6(0.6, comparable with that of the analogous species cis-VO(dhp) 2(HSA) and cis-VO(dhp) 2(hTf). Finally, with these new values of log β, the predicted percent distribution of an insulin-enhancing VO 2+ ag input type="button" ent between the high molecular mass (hTf, HSA, and IgG) and low molecular mass (lactate) components of the blood serum at physiological conditions is calculated. © 2011 American Chemical Society.

Tibuzzi A.,CNR Institute of Neuroscience
Advances in Experimental Medicine and Biology | Year: 2010

This chapter provides a short review of the main regulations concerning functional food and nutraceutical products set out by the US Food and Drug Administration and in the European Union by the European Commission. The directives are presented in chronological order with an overview on the reaction and feedback they received from consumers and manufacturing industry. A comparison between the US and EU regulations, their acceptance and impact on the market is presented, together with a final suggestion to enhance the future development and distribution of functional products, which belong to an equivocal area between food and drugs. © 2010 Landes Bioscience and Springer Science+Business Media, LLC.

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.

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.

Vandamme J.,Copenhagen University | Lettier G.,Copenhagen University | Sidoli S.,University of Southern Denmark | Di Schiavi E.,CNR Institute of Neuroscience | And 2 more authors.
PLoS Genetics | Year: 2012

Epigenetic modifications influence gene expression and provide a unique mechanism for fine-tuning cellular differentiation and development in multicellular organisms. Here we report on the biological functions of UTX-1, the Caenorhabditis elegans homologue of mammalian UTX, a histone demethylase specific for H3K27me2/3. We demonstrate that utx-1 is an essential gene that is required for correct embryonic and postembryonic development. Consistent with its homology to UTX, UTX-1 regulates global levels of H3K27me2/3 in C. elegans. Surprisingly, we found that the catalytic activity is not required for the developmental function of this protein. Biochemical analysis identified UTX-1 as a component of a complex that includes SET-16(MLL), and genetic analysis indicates that the defects associated with loss of UTX-1 are likely mediated by compromised SET-16/UTX-1 complex activity. Taken together, these results demonstrate that UTX-1 is required for many aspects of nematode development; but, unexpectedly, this function is independent of its enzymatic activity. © 2012 Vandamme et al.

Grimaldi S.,CNR Institute of Neuroscience
Journal of Physics: Conference Series | Year: 2011

This work arose from the necessity to up date and clarify some basic concepts in contemporary medical practice such as those of health, disease, therapy and prevention. According to this perspective the work starts with a general epistemological review and goes on with an epistemological revision of biology and medicine. The concept of adaptation and the central role of the brain is then analysed and stated as the base to next consideration and deepening from a biophysical perspective. Physio-pathology of adaptation is assumed as a key concept in the definition and in the understanding of health and disease. A huge amount of endogenous and external stimuli has to be processed and response to them may lead to increase, stability or decrease of coherence in agreement with Frohlich's pioneering ideas. In this framework, the concept of stress, allostasis and allostatic load are outlined. Allostasis is defined as the capability of keeping stability through dynamic changes. A particular attention is paid to the emerging paradigms in biology and medicine especially those of system biology and system medicine trying to integrate the concept of complexity and hierarchical organization of the information flow in living organisms and in humans. In this framework biophysical signalling could play a significant role in modulating endogenous dynamics and in mediating external interactions. Additionally biophysical mechanisms could be involved in biological systems inner communication and could be responsible for the maintenance of systems inner coherence. The integration of the biophysical paradigm into contemporary medical practice is leading from one side to a better understanding of many pathways in physiopathology and from the other side to some new effective clinical applications. System Information Therapy is, for instance, is rising as a suitable and coherent tool in the application of thise concept being able to restore the self regulation and self regeneration capabilities both at the local and at the system level operating with endogenous and external electromagnetic signals in the range of the extremely low frequency electromagnetic signals. Some practical applications are described such as the clinical detection and treatment of fluctuating asymmetry by Vega Select 719. Fluctuating asymmetry, as well known, is related to the presence of an allostatic load and its disappearance after a biophysical treatment is a good clinical evidence of restoring of allostasis mediated by the brain at systemic level presumably through a biophysical repatterning in which we assume a key role should be played by membranes, cytoskeleton and especially by microtubules.

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.

Chinappi M.,University of Rome La Sapienza | Cecconi F.,CNR Institute of Neuroscience | Casciola C.M.,University of Rome La Sapienza
Philosophical Magazine | Year: 2011

We propose a computational model for the study of maltose binding protein translocation across α-hemolysin nanopores. The phenomenological approach simplifies both the pore and the polypeptide chain; however it retains the basic structural protein-like properties of the maltose binding protein by promoting the correct formation of its native key interactions. By considering different observables characterising the channel blockade and molecule transport, we verified that MD simulations reproduce qualitatively the behaviour observed in a recent experiment. Simulations reveal that blockade events consist of a capture stage, to some extent related to the unfolding kinetics, and a single file translocation process in the channel. A threshold mechanics underlies the process activation with a critical force depending on the protein denaturation state. Finally, our results support the simple interpretation of translocation via first-passage statistics of a driven diffusion process of a single reaction coordinate. © 2011 Taylor & Francis.

Lamura A.,CNR Institute of Neuroscience | Gompper G.,Julich Research Center
EPL | Year: 2013

The dynamics and rheology of suspensions of fluid vesicles or red blood cells is investigated by a combination of molecular dynamics and mesoscale hydrodynamics simulations in two dimensions. The vesicle suspension is confined between two no-slip walls, which are driven externally to generate a shear flow with shear rate γ. The flow behavior is studied as a function of γ, the volume fraction of vesicles, and the viscosity contrast between inside and outside fluids. Results are obtained for the encounter and interactions of two vesicles, the intrinsic viscosity of the suspension, and the cell-free layer near the walls. Copyright © EPLA, 2013.

Azpiroz J.M.,Donostia International Physics Center | Infante I.,Donostia International Physics Center | Lopez X.,Donostia International Physics Center | Ugalde J.M.,Donostia International Physics Center | De Angelis F.,CNR Institute of Neuroscience
Journal of Materials Chemistry | Year: 2012

We present a systematic investigation of the structural, electronic and optical properties of wurtzite-like ZnX (X = O, S, Se, Te) nanostructures at the DFT/TDDFT level of theory. To provide a direct comparison with the experiment, realistic 1.0-1.5 nm quantum dots have been built up from the bulk. Low-lying computed excitation energies agree well with the available experimental data. The broad excitation profiles and narrow emission spectra typical of semiconductor quantum dots could be explained by the fact that the LUMO is the state accepting the electron of the low-lying TDDFT excitations calculated. Calculated binding energies for the Zn 3d shell have been found to be 0.5 eV lower than those of the corresponding bulk materials. Anion vacancies can explain the visible light emission of ZnX by introducing a trap state into the bandgap of the nanostructures, in agreement with previous theoretical and experimental works on ZnO. Calculations on rod- and sheet-like prototype clusters point to a significant quantum confinement effect on the optoelectronic properties of Zn-based nanomaterials. © 2012 The Royal Society of Chemistry.

Zani A.,CNR Institute of Neuroscience | Proverbio A.M.,University of Milan Bicocca
Behavioral and Brain Functions | Year: 2012

Background: There is at present crescent empirical evidence deriving from different lines of ERPs research that, unlike previously observed, the earliest sensory visual response, known as C1 component or P/N80, generated within the striate cortex, might be modulated by selective attention to visual stimulus features. Up to now, evidence of this modulation has been related to space location, and simple features such as spatial frequency, luminance, and texture. Additionally, neurophysiological conditions, such as emotion, vigilance, the reflexive or voluntary nature of input attentional selection, and workload have also been related to C1 modulations, although at least the workload status has received controversial indications. No information is instead available, at present, for objects attentional selection.Methods: In this study object- and space-based attention mechanisms were conjointly investigated by presenting complex, familiar shapes of artefacts and animals, intermixed with distracters, in different tasks requiring the selection of a relevant target-category within a relevant spatial location, while ignoring the other shape categories within this location, and, overall, all the categories at an irrelevant location. EEG was recorded from 30 scalp electrode sites in 21 right-handed participants.Results and Conclusions: ERP findings showed that visual processing was modulated by both shape- and location-relevance per se, beginning separately at the latency of the early phase of a precocious negativity (60-80 ms) at mesial scalp sites consistent with the C1 component, and a positivity at more lateral sites. The data also showed that the attentional modulation progressed conjointly at the latency of the subsequent P1 (100-120 ms) and N1 (120-180 ms), as well as later-latency components. These findings support the views that (1) V1 may be precociously modulated by direct top-down influences, and participates to object, besides simple features, attentional selection; (2) object spatial and non-spatial features selection might begin with an early, parallel detection of a target object in the visual field, followed by the progressive focusing of spatial attention onto the location of an actual target for its identification, somehow in line with neural mechanisms reported in the literature as "object-based space selection", or with those proposed for visual search. © 2012 Zani and Proverbio; licensee BioMed Central Ltd.

Napoletano M.,CNR Institute of Neuroscience
Frontiers in bioscience (Elite edition) | Year: 2010

Ochratoxin A (OTA) is a mycotoxin produced by fungal of Aspergillus species absorbed in human through contaminate food in gastrointestinal tract. OTA has been demonstrated to be teratogenic in a number of species including mice and potentially human. Mice exposed in uterus to OTA develop craniofacial abnormalities such as exencephaly, microencephaly, microphthalmia and facial clefts. An important role in differentiation of maxillofacial are exerted by the Hox related genes Dlx and Msx. In the present investigation we have confirmed that 2.75 mg/kg body weight OTA, given at gestational day 7.5, induces significant developmental craniofacial anomalies in mice and we have demonstrated the down expression of Dlx5, a member of Dlx gene family, that seems to be responsible of the observed deformities. These results support the hypothesis that Dlx5 is a target for ochratoxin and the inhibition of its function, directly or indirectly, could be at origin of the observed differentiation defects.

Fila G.,Italian Agricultural Research Council | Sartorato I.,CNR Institute of Neuroscience
Agricultural and Forest Meteorology | Year: 2011

The partitioning of light absorption is difficult to assess in natural or cultivated mixed vegetation canopies. Previous research has shown that it is possible to estimate light absorption in monospecific canopies from the Leaf Mass per Area (MA), which is closely related to the prevailing light conditions experienced by the leaf during its development.The effectiveness of this approach in assessing light partitioning at individual plant level was tested on monospecific and mixed crop/weed plots. Canopy absorbed PAR (APAR) was estimated in monocultures or 1:1 mixed stands of Abutilon theophrasti Medicus and Glycine max L. (soybean) using a relationship between intercepted PAR (IPAR) and MA, calibrated at individual leaf level against incident light measurements. The accuracy of estimates was evaluated through comparison with APAR calculated from incident light measurements taken independently at various heights at whole canopy level.The use of the experimentally assessed relationship of IPAR vs. MA provided acceptable absorption estimates. The average departure of estimates from measurements, expressed as Root Mean Squared Error (RMSE), was 10.2%. By comparison, a numerically optimized version of the model that excluded the effects of experimental errors in single-leaf PAR measurements, yielded estimates with an average RMSE of 4.8%. The lower accuracy of the estimates based on the experimental IPAR-MA relationship was due to experimental error but also to a high sensitivity of the MA-based estimates to the model coefficients.MA variability in monoculture or mixed canopies was confirmed to be highly dependent on the PAR distribution, so MA is potentially suitable for use as a predictor of light absorption. However, due to the sensitivity of the model, a high experimental accuracy in IPAR-MA assessment as well as in MA and LAI distribution has to be guaranteed in order to perform reliable estimates by this method. © 2011 Elsevier B.V.

Mallamaci F.,CNR Institute of Neuroscience
Transplantation | Year: 2015

BACKGROUND: The clinical relevance of ambulatory blood pressure monitoring (ABPM) for risk stratification in renal transplant patients still remains poorly defined. METHODS: We investigated the association between clinic and ABPM with an established biomarker of atherosclerosis (intima-media thickness [IMT] by echo-color Doppler) in a large, inclusive survey (n = 172) in renal transplant patients at a single institution. RESULTS: Forty-two patients (24%) were classified as hypertensive by ABPM criteria and 29 (17%) by clinic blood pressure (BP) criteria. Average daytime and nighttime BP was 126 ± 12/78 ± 9 mm Hg and 123 ± 13/74 ± 10 mm Hg, respectively. Forty-five patients (26%) were classified as hypertensive by the daytime criterion (>135/85 mm Hg) and a much higher proportion (n = 119, 69%) by the nighttime criterion (>120/70 mm Hg). Sixty-two patients (36%) had a night-day ratio of 1 or greater, indicating clear-cut nondipping. The average nighttime systolic BP (r = 0.24, P = 0.001) and the night-day systolic BP ratio (r = 0.23, P = 0.002) were directly related to IMT, and these associations were much more robust than the 24-hour systolic BP-IMT relationship (r = 0.16, P = 0.04). Average daytime BP and clinic B were unrelated to IMT. In a multiple regression analysis adjusting for confounders, the night-day systolic BP ratio maintained an independent association with IMT (β = 0.14, P = 0.04). CONCLUSIONS: In renal transplant patients, the prevalence of nocturnal hypertension by far exceeds the prevalence of hypertension as assessed by clinic, daytime, and 24-hour ABPM. Nighttime systolic BP and the night-day ratio but no other BP metrics are independently associated with IMT. Blood pressure during nighttime may provide unique information for the assessment of cardiovascular risk attributable to BP burden in renal transplant patients. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.

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.

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.

Trenkwalder A.,CNR Institute of Neuroscience
Nature Physics | Year: 2016

Symmetry-breaking quantum phase transitions play a key role in several condensed matter, cosmology and nuclear physics theoretical models. Its observation in real systems is often hampered by finite temperatures and limited control of the system parameters. In this work we report, for the first time, the experimental observation of the full quantum phase diagram across a transition where the spatial parity symmetry is broken. Our system consists of an ultracold gas with tunable attractive interactions trapped in a spatially symmetric double-well potential. At a critical value of the interaction strength, we observe a continuous quantum phase transition where the gas spontaneously localizes in one well or the other, thus breaking the underlying symmetry of the system. Furthermore, we show the robustness of the asymmetric state against controlled energy mismatch between the two wells. This is the result of hysteresis associated with an additional discontinuous quantum phase transition that we fully characterize. Our results pave the way to the study of quantum critical phenomena at finite temperature, the investigation of macroscopic quantum tunnelling of the order parameter in the hysteretic regime and the production of strongly quantum entangled states at critical points. © 2016 Nature Publishing Group

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.

Sanna D.,CNR Institute of Neuroscience | Micera G.,University of Sassari | Garribba E.,University of Sassari
Inorganic Chemistry | Year: 2010

The possible biotransformations in the blood serum of four representative insulin-enhancing vanadium compounds, [VO(6-mepic)2], cis-[VO(pic)2(H20)], [VO(acac)2], and [VO(dhp)2], where 6-mepic, pic, acac, and dhp indicate the deprotonated forms of 6-methylpicolinic and picolinic acids, acetylacetone, and 1,2-dimethyl-3-hydroxy-4(1 H)-pyridinone, were examined. In particular, the behavior of the quinary systems formed by the insulin-enhancing species, human serum apo-transferrin (hTf), human serum albumin (HSA), and lactate (lact) or citrate (citr) at physiological pH and conditions was studied. The results indicate that, besides the case in which the ligand is very weak like 6-mepic, the carrier can interact in some form with VO2+ ion until its intake into the cell. In fact with stronger ligands like pic, acac, and dhp, VO 2+ is transported not only by transferrin but also as [VO(carrier)2] and as mixed species VO 2+-hTF-carrier. There are two ways in which the undissociated form of a bis-chelated complex can interact with transferrin, one "specific" when the carrier possesses a carboxylate group and behaves like a synergistic anion, and another "non-specific" when an imidazole nitrogen of a histidine residue from hTf replaces an equatorially coordinated water molecule giving rise to a ternary species with cis-octahedral geometry and cis-VO(carrier)2(hTf) stoichiometry. It is found that also albumin can participate in the transport of an insulin-enhancing compound forming a mixed species cis-VO(carier) 2(HSA), when the carrier stabilizes in aqueous solution the cisoctahedral form, or the dinuclear compound (VO)2 d HSA, when the carrier forms unstable complexes. These insights were confirmed through density functional theory (DFT) calculations. © 2009 American Chemical Society.

Rossi M.,CNR Institute of Neuroscience
Digestive Diseases | Year: 2015

Background: Celiac disease (CD) results from an alteration in the oral tolerance to dietary gluten. The response to gluten is normally tightly regulated and involves the secretion of TGF-β and IL-10 from different subtypes of regulatory T cells (Tregs). Interestingly, in addition to proinflammatory cytokines, the inflamed CD mucosa also contains high levels of T cell-derived IL-10 compared with treated CD patients or normal donors. Furthermore, most studies describe an increase in the number of Foxp3+ Tregs in the small intestinal mucosa in CD patients compared to controls. This paradoxical condition suggests that regulatory mechanisms might operate to counterbalance the abnormal gliadin-triggered immune activation in untreated mucosa. Indeed, addition of exogenous IL-10 to mucosal cultures from treated CD patients can suppress gliadin-induced T cell activation. Considering the central role of adaptive immunity in CD, the development of strategies to stimulate these mechanisms is a primary goal of efforts to restore gluten tolerance. Key Messages: Different immunomodulatory strategies have been explored. NexVax2, a desensitizing vaccine that uses three dominant gluten peptides administered subcutaneously to induce a tolerogenic response in CD patients, is under development. Alternatively, the potential of substituted, cyclic or dimeric peptide analogues as blockers to prevent HLA from binding to the immunodominant gliadin epitopes has been demonstrated in vitro. In line with these results, we recently found that modified (transamidated) gliadins influenced the immune response in intestinal biopsy samples from CD patients with overt disease by drastically reducing the production of IFN-γ. Notably, in a mouse model, transamidated gliadins reverted the phenotype of the gliadin-inducible immune response from an inflammatory phenotype to an anti-inflammatory phenotype. Conclusions: Various approaches are currently under investigation to recover gluten tolerance based on the use of both modified and native antigen molecules. More specific studies are now required to test the efficacy of such strategies for preventing CD. © 2015 S. Karger AG, Basel.

Hubscher U.,University of Zurich | Maga G.,CNR Institute of Neuroscience
Current Opinion in Chemical Biology | Year: 2011

Maintenance of genetic stability is of crucial importance for any form of life. Before cell division in each mammalian cell, the process of DNA replication must faithfully duplicate three billion bases with an absolute minimum of mistakes. This is complicated by the fact that DNA itself is highly reactive and is constantly attacked by endogenous and exogenous factors leading to 50,000-100,000 different damages in the DNA of human cells every day. In this mini-review we will focus on lesion bypass by DNA polymerase machines either in replication or repair, with particular focus on the repair of oxidative lesions. © 2011 Elsevier Ltd.

Dalton C.M.,University College London | Szabadkai G.,University College London | Szabadkai G.,CNR Institute of Neuroscience | Carroll J.,University College London | Carroll J.,Monash University
Journal of Cellular Physiology | Year: 2014

Mitochondria provide the primary source of ATP in the oocyte and early embryo and mitochondrial dysfunction and deficit of mitochondria-derived ATP has been linked to suboptimal developmental competence. We have undertaken a study of ATP in the maturing mouse oocyte using a novel recombinant FRET based probe, AT1.03. We show that AT1.03 can be successfully used to monitor cytosolic ATP levels in single live oocytes over extended time periods. We find that ATP levels undergo dynamic changes associated with specific maturational events and that oocytes display altered rates of ATP consumption at different stages of maturation. Cumulus enclosed oocytes have a higher ATP level during maturation than denuded oocytes and this can be abolished by inhibition of gap junctional communication between the oocyte and cumulus cells. Our work uses a new approach to shed light on regulation of ATP levels and ATP consumption during oocyte maturation. © 2013 Wiley Periodicals, Inc.

Picconi B.,Laboratorio Of Neurofisiologia | Piccoli G.,CNR Institute of Neuroscience | Calabresi P.,Laboratorio Of Neurofisiologia | Calabresi P.,NeuroLogica
Advances in Experimental Medicine and Biology | Year: 2012

Activity-dependent modifications in synaptic efficacy, such as long-term depression (LTD) and long-term potentiation (LTP), represent key cellular substrates for adaptive motor control and procedural memory. The impairment of these two forms of synaptic plasticity in the nucleus striatum could account for the onset and the progression of motor and cognitive symptoms of Parkinson's disease (PD), characterized by the massive degeneration of dopaminergic neurons. In fact, both LTD and LTP are peculiarly controlled and modulated by dopaminergic transmission coming from nigrostriatal terminals. Changes in corticostriatal and nigrostriatal neuronal excitability may influence profoundly the threshold for the induction of synaptic plasticity, and changes in striatal synaptic transmission efficacy are supposed to play a role in the occurrence of PD symptoms. Understanding of these maladaptive forms of synaptic plasticity has mostly come from the analysis of experimental animal models of PD. A series of cellular and synaptic alterations occur in the striatum of experimental parkinsonism in response to the massive dopaminergic loss. In particular, dysfunctions in trafficking and subunit composition of glutamatergic NMDA receptors on striatal efferent neurons contribute to the clinical features of the experimental parkinsonism. Interestingly, it has become increasingly evident that in striatal spiny neurons, the correct assembly of NMDA receptor complex at the postsynaptic site is a major player in early phases of PD, and it is sensitive to distinct degrees of DA denervation. The molecular defects at the basis of PD progression may be not confined just at the postsynaptic neuron: accumulating evidences have recently shown that the genes linked to PD play a critical role at the presynaptic site. DA release into the synaptic cleft relies on a proper presynaptic vesicular transport; impairment of SV trafficking, modification of DA flow, and altered presynaptic plasticity have been described in several PD animal models. Furthermore, an impaired DA turnover has been described in presymptomatic PD patients. Thus, given the pathological events occurring precociously at the synapses of PD patients, post- and presynaptic sites may represent an adequate target for early therapeutic intervention. © 2012 Springer-Verlag/WIen.

Perrone M.R.,University of Salento | De Tomasi F.,University of Salento | Gobbi G.P.,CNR Institute of Neuroscience
Atmospheric Chemistry and Physics | Year: 2014

An approach based on the graphical method of Gobbi and co-authors (2007) is introduced to estimate the dependence on altitude of the aerosol fine mode radius (Rf) and of the fine mode contribution (η) to the aerosol optical thickness (AOT) from three-wavelength lidar measurements. The graphical method of Gobbi and co-authors (2007) was applied to AERONET (AErosol RObotic NETwork) spectral extinction observations and relies on the combined analysis of the Ångstrom exponent (die) and its spectral curvature Δdie. Lidar measurements at 355, 532 and 1064 nm were used in this study to retrieve the vertical profiles of die and Δdie and to estimate the dependence on altitude of Rf and η(532 nm) from the die-Δdie combined analysis. Lidar measurements were performed at the Department of Mathematics and Physics of the Universita' del Salento, in south-eastern Italy. Aerosol from continental Europe, the Atlantic, northern Africa, and the Mediterranean Sea are often advected over south-eastern Italy and as a consequence, mixed advection patterns leading to aerosol properties varying with altitude are dominant. The proposed approach was applied to ten measurement days to demonstrate its feasibility in different aerosol load conditions. The selected days were characterized by AOTs spanning the 0.26-0.67, 0.15-0.39, and 0.04-0.27 range at 355, 532, and 1064 nm, respectively. Mean lidar ratios varied within the 31-83, 32-84, and 11-47 sr range at 355, 532, and 1064 nm, respectively, for the high variability of the aerosol optical and microphysical properties. die values calculated from lidar extinction profiles at 355 and 1064 nm ranged between 0.1 and 2.5 with a mean value ± 1 standard deviation equal to 1.3 ± 0.7. Δdie varied within the-0.1-1 range with mean value equal to 0.25 ± 0.43. Rf and η(532 nm) values spanning the 0.05-0.3 μm and the 0.3-0.99 range, respectively, were associated with the die-Δdie data points. Rf and η values showed no dependence on the altitude. 60% of the data points were in the Δdie-die space delimited by the η and Rf curves varying within 0.80-0.99 and 0.05-0.15 μm, respectively, for the dominance of fine-mode particles in driving the AOT over south-eastern Italy. Vertical profiles of the linear particle depolarization ratio retrieved from lidar measurements, aerosol products from AERONET sun photometer measurements collocated in space and time, analytical back trajectories, satellite true colour images, and dust concentrations from the BSC-DREAM (Barcelona Super Computing Center-Dust REgional Atmospheric Model) model were used to demonstrate the robustness of the proposed method. © 2014 Author(s).

Trotta E.,CNR Institute of Neuroscience
PLoS ONE | Year: 2014

The minimum free energy (MFE) of ribonucleic acids (RNAs) increases at an apparent linear rate with sequence length. Simple indices, obtained by dividing the MFE by the number of nucleotides, have been used for a direct comparison of the folding stability of RNAs of various sizes. Although this normalization procedure has been used in several studies, the relationship between normalized MFE and length has not yet been investigated in detail. Here, we demonstrate that the variation of MFE with sequence length is not linear and is significantly biased by the mathematical formula used for the normalization procedure. For this reason, the normalized MFEs strongly decrease as hyperbolic functions of length and produce unreliable results when applied for the comparison of sequences with different sizes. We also propose a simple modification of the normalization formula that corrects the bias enabling the use of the normalized MFE for RNAs longer than 40 nt. Using the new corrected normalized index, we analyzed the folding free energies of different human RNA families showing that most of them present an average MFE density more negative than expected for a typical genomic sequence. Furthermore, we found that a well-defined and restricted range of MFE density characterizes each RNA family, suggesting the use of our corrected normalized index to improve RNA prediction algorithms. Finally, in coding and functional human RNAs the MFE density appears scarcely correlated with sequence length, consistent with a negligible role of thermodynamic stability demands in determining RNA size. © 2014 Edoardo Trotta.

Saija F.,CNR Institute of Neuroscience
Physical Chemistry Chemical Physics | Year: 2011

The fourth virial coefficient of symmetric nonadditive hard-disc mixtures is calculated over a wide range of nonadditivity. The irreducible cluster integrals were evaluated numerically using a standard Monte Carlo method. The coexistence line relative to the fluid-fluid phase transition, calculated through two equations of state built using the new virial coefficients, is compared with some numerical simulation results. © the Owner Societies 2011.

Ciuciu A.I.,CNR Institute of Neuroscience | Cywinski P.J.,Fraunhofer Institute for Applied Polymer Research
RSC Advances | Year: 2014

Hydrogels are cross-linked water-containing polymer networks that are formed by physical, ionic or covalent interactions. In recent years, they have attracted significant attention because of their unique physical properties, which make them promising materials for numerous applications in food and cosmetic processing, as well as in drug delivery and tissue engineering. Hydrogels are highly water-swellable materials, which can considerably increase in volume without losing cohesion, are biocompatible and possess excellent tissue-like physical properties, which can mimic in vivo conditions. When combined with highly precise manufacturing technologies, such as two-photon polymerization (2PP), well-defined three-dimensional structures can be obtained. These structures can become scaffolds for selective cell-entrapping, cell/drug delivery, sensing and prosthetic implants in regenerative medicine. 2PP has been distinguished from other rapid prototyping methods because it is a non-invasive and efficient approach for hydrogel cross-linking. This review discusses the 2PP-based fabrication of 3D hydrogel structures and their potential applications in biotechnology. A brief overview regarding the 2PP methodology and hydrogel properties relevant to biomedical applications is given together with a review of the most important recent achievements in the field. This journal is © the Partner Organisations 2014.

Bianucci M.,CNR Institute of Neuroscience
Geophysical Research Letters | Year: 2016

This letter has two main goals. The first one is to give a physically reasonable explanation for the use of stochastic models for mimicking the apparent random features of the El Ninõ-Southern Oscillation (ENSO) phenomenon. The second one is to obtain, from the theory, an analytical expression for the equilibrium density function of the anomaly sea surface temperature, an expression that fits the data from observations well, reproducing the asymmetry and the power law tail of the histograms of the NIÑO3 index. We succeed in these tasks exploiting some recent theoretical results of the author in the field of the dynamical origin of the stochastic processes. More precisely, we apply this approach to the celebrated recharge oscillator model (ROM), weakly interacting by a multiplicative term, with a general deterministic complex forcing (Madden-Julian Oscillations, westerly wind burst, etc.), and we obtain a Fokker-Planck equation that describes the statistical behavior of the ROM. ©2016. American Geophysical Union.

Tomadin A.,Austrian Academy of Sciences | Fazio R.,CNR Institute of Neuroscience
Journal of the Optical Society of America B: Optical Physics | Year: 2010

Coupled quantum electrodynamics (QED) cavities have been recently proposed as new systems to simulate a variety of equilibrium and nonequilibrium many-body phenomena. We present a brief review of their main properties together with a survey of the latest developments of the field and some perspectives concerning their experimental realizations and possible new theoretical directions. © 2010 Optical Society of America.

Macchi A.,CNR Institute of Neuroscience | Benedetti C.,University of Bologna
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2010

Radiation Pressure Acceleration (RPA) by circularly polarized laser pulses is emerging as a promising way to obtain efficient acceleration of ions. We briefly review theoretical work on the topic, aiming at characterizing suitable experimental scenarios. We discuss the two reference cases of RPA, namely the thick target ("Hole Boring") and the (ultra)thin target ("Light Sail") regimes. The different scaling laws of the two regimes, the related experimental challenges and their suitability for foreseen applications are discussed. © 2010 Elsevier B.V. All rights reserved.

Giazotto F.,CNR Institute of Neuroscience | Peltonen J.T.,Aalto University | Meschke M.,Aalto University | Pekola J.P.,Aalto University
Nature Physics | Year: 2010

When a superconductor is placed close to a non-superconducting metal, it can induce superconducting correlations in the metal1-10, known as the proximity effect11. Such behaviour modifies the density of states (DOS) in the normal metal12-15 and opens a minigap 12,13,16 with an amplitude that can be controlled by changing the phase of the superconducting order parameter12,15. Here, we exploit such behaviour to realize a new type of interferometer, the superconducting quantum interference proximity transistor (SQUIPT), for which the operation relies on the modulation with the magnetic field of the DOS of a proximized metal embedded in a superconducting loop. Even without optimizing its design, this device shows extremely low flux noise, down to ∼10-5 φ0 Hz-1/2 (φ0 ≃2×10 -15 Wb is the flux quantum) and dissipation several orders of magnitude smaller than in conventional superconducting interferometers 17-19. With optimization, the SQUIPT could significantly increase the sensitivity with which small magnetic moments are detected. © 2010 Macmillan Publishers Limited. All rights reserved.

Stroppa A.,University of LAquila | Marsman M.,University of Vienna | Kresse G.,University of Vienna | Picozzi S.,CNR Institute of Neuroscience
New Journal of Physics | Year: 2010

By performing accurate ab initio density functional theory (DFT) calculations, we study the role of 4f electrons in stabilizing the magneticfield-induced ferroelectric state of DyFeO3. We confirm that the ferroelectric polarization is driven by an exchange-strictive mechanism, working between adjacent spin-polarized Fe and Dy layers, as suggested by Y Tokunaga (2008 Phys. Rev. Lett. 101 097205). A careful electronic structure analysis suggests that coupling between Dy and Fe spin sublattices is mediated by Dy-d and O-2p hybridization. Our results are robust with respect to the different computational schemes used for d and f localized states, such as the DFT +U method, the Heyd-Scuseria-Ernzerhof (HSE) hybrid functional and the GW approach. Our findings indicate that the interaction between the f and d sublattices might be used to tailor the ferroelectric and magnetic properties of multiferroic compounds. © IOP Publishing Ltd and Deutsche Physikalische Gesellschaft.

Ciattoni A.,CNR Institute of Neuroscience | Rizza C.,University of LAquila | Palange E.,University of LAquila
Optics Letters | Year: 2010

We investigate propagation of a transverse magnetic field through a nonlinear metamaterial slab of subwavelength thickness and with a very small and negative linear dielectric permittivity. We prove that, for a given input intensity, the output intensity is a multivalued function of the field incidence angle so that the transmissivity exhibits angular multistability and a pronounced directional hysteresis behavior. The predicted directional hysteresis is a consequence of the fact that the linear and nonlinear contributions to the overall dielectric response can be comparable so that the electromagnetic matching conditions at the output slab boundary allow more than one field configuration within the slab to be compatible with the transmitted field. © 2010 Optical Society of America.

Pucci M.,CNR Institute of Neuroscience
IEEE Transactions on Industry Applications | Year: 2014

This paper presents the state space-vector dynamic model of the linear induction motor (LIM) taking into consideration the dynamic end effects. Starting from the space-vector equivalent circuit of the LIM, the complete set of space-vector equations has been deduced. Afterward, first the so-called voltage and current flux models have been written, from which the complete state space-vector representation has been given. The complete thrust expression including the end-effect braking force has also been introduced in the model. The complete state space-vector model, electromagnetic and mechanical part, has been implemented in numerical simulation and has been validated by comparing the results with those obtainable with a finite-element analysis and experiments. Results show that, even with a machine with a limited presence of the dynamic end effects, the adoption of a this model permits a better estimation of both the electric quantities, e.g., inductor current, and the mechanical quantities, e.g., linear speed, with respect to the classic rotating induction motor model. © 2013 IEEE.

Spagnuolo M.,CNR Institute of Neuroscience
IEEE Computer Graphics and Applications | Year: 2016

In the last decade, sensor, communication, and computing technologies have advanced rapidly, producing dramatic changes in our daily lives and in a variety of application domains. Emerging technologies are leading us to a gradual, but inescapable integration of our material and digital realities and the advent of cyber-physical worlds. Although attaining visual realism is within the grasp of current 3D modeling approaches, it is less clear whether current modeling techniques will accommodate the needs of human communication and of the applications that we can already envisage in those futuristic worlds. Inspired by the evolution trends of the Web, this article describes the evolution of shape modeling from the Shape 1.0 geometry-only, mesh-based stage to the forthcoming semantics-driven Shape 4.0 era. © 1981-2012 IEEE.

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.

Cecconi C.,CNR Institute of Neuroscience
Methods in molecular biology (Clifton, N.J.) | Year: 2011

In this chapter, we describe a method that extends the use of optical tweezers to the study of the folding mechanism of single protein molecules. This method entails the use of DNA molecules as molecular handles to manipulate individual proteins between two polystyrene beads. The DNA molecules function as spacers between the protein and the beads, and keep the interactions between the tethering surfaces to a minimum. The handles can have different lengths, be attached to any pair of exposed cysteine residues, and be used to manipulate both monomeric and polymeric proteins. By changing the position of the cysteine residues on the protein surface, it is possible to apply the force to different portions of the protein and along different molecular axes. Circular dichroism and enzymatic activity studies have revealed that for many proteins, the handles do not significantly affect the folding behavior and the structure of the tethered protein. This method makes it possible to study protein folding in the physiologically relevant low-force regime of optical tweezers and enables us to monitor processes - such as refolding events and fluctuations between different molecular conformations - that could not be detected in previous force spectroscopy experiments.

Blacker T.S.,University College London | Mann Z.F.,University College London | Gale J.E.,University College London | Ziegler M.,University of Bergen | And 4 more authors.
Nature Communications | Year: 2014

NAD is a key determinant of cellular energy metabolism. In contrast, its phosphorylated form, NADP, plays a central role in biosynthetic pathways and antioxidant defence. The reduced forms of both pyridine nucleotides are fluorescent in living cells but they cannot be distinguished, as they are spectrally identical. Here, using genetic and pharmacological approaches to perturb NAD(P)H metabolism, we find that fluorescence lifetime imaging (FLIM) differentiates quantitatively between the two cofactors. Systematic manipulations to change the balance between oxidative and glycolytic metabolism suggest that these states do not directly impact NAD(P)H fluorescence decay rates. The lifetime changes observed in cancers thus likely reflect shifts in the NADPH/NADH balance. Using a mathematical model, we use these experimental data to quantify the relative levels of NADH and NADPH in different cell types of a complex tissue, the mammalian cochlea. This reveals NADPH-enriched populations of cells, raising questions about their distinct metabolic roles. © 2014 Macmillan Publishers Limited. All rights reserved.

Dabo I.,Pennsylvania State University | Ferretti A.,CNR Institute of Neuroscience | Marzari N.,Ecole Polytechnique Federale de Lausanne
Topics in Current Chemistry | Year: 2014

Density-functional theory is an extremely powerful and widely used tool for quantum simulations. It reformulates the electronic-structure problem into a functional minimization with respect to the charge density of interacting electrons in an external potential. While exact in principle, it is approximate in practice, and even in its exact form it is meant to reproduce correctly only the total energy and its derivatives, such as forces, phonons, or dielectric properties. Quasiparticle levels are outside the scope of the theory, with the exception of the highest occupied state, since this is given by the derivative of the energy with respect to the number of electrons. A fundamental property of the exact energy functional is that of piecewise linearity at fractional occupations in between integer fillings, but common approximations do not follow such piecewise behavior, leading to a discrepancy between total and partial electron removal energies. Since the former are typically well described, and the latter provide, via Janak’s theorem, orbital energies, this discrepancy leads to a poor comparison between predicted and measured spectroscopic properties. We illustrate here the powerful consequences that arise from. © Springer-Verlag Berlin Heidelberg 2014.

Lim J.L.,CNR Institute of Neuroscience
Australian and New Zealand Journal of Obstetrics and Gynaecology | Year: 2010

Voiding difficulty and urinary retention is a common phenomenon in the immediate post-partum period. The importance of prompt diagnosis and appropriate management of this condition cannot be over-emphasised as it is the key to ensuring a rapid return to normal bladder function. Despite this, studies revealed a low level of awareness of this problem amongst obstetric units, and there is little information regarding this condition in the published literature. This article aims at reviewing the available literature and providing an informative guide as to the associated risk factors, pathogenesis, clinical presentation and management of this largely overlooked condition. © 2010 The Royal Australian and New Zealand College of Obstetricians and Gynaecologists.

The phylogenetic analyses as far as the identification of the number of domains of life is concerned have not reached a clear conclusion. In the attempt to improve this circumstance, I introduce the concept that the amino acids codified in the genetic code might be of markers with outstanding phylogenetic power. In particular, I hypothesise the existence of a biosphere populated, for instance, by three groups of organisms having different genetic codes because codifying at least a different amino acid. Evidently, these amino acids would mark the proteins that are present in the three groups of organisms in an unambiguous way. Therefore, in essence, this mark would not be other than the one that we usually try to make in the phylogenetic analyses in which we transform the protein sequences in phylogenetic trees, for the purpose to identify, for example, the domains of life. Indeed, this mark would allow to classify proteins without performing phylogenetic analyses because proteins belonging to a group of organisms would be recognisable as marked in a natural way by at least a different amino acid among the diverse groups of organisms. This conceptualisation answers the question of how many fundamental kinds of cells have evolved from the Last Universal Common Ancestor (LUCA), as the genetic code has unique proprieties that make the codified amino acids excellent phylogenetic markers. The presence of the formyl-methionine only in proteins of bacteria would mark them and would identify these as domain of life. On the other hand, the presence of pyrrolysine in the genetic code of the euryarchaeota would identify them such as another fundamental kind of cell evolved from the LUCA. Overall, the phylogenetic distribution of formyl-methionine and pyrrolysine would identify at least two domains of life - Bacteria and Archaea - but their number might be actually four; that is to say, Bacteria, Euryarchaeota, archeobacteria that are not euryarchaeota and Eukarya. The usually accepted domains of life represented by Bacteria, Archaea and Eukarya are not compatible with the phylogenetic distribution of these two amino acids and therefore this last classification might be mistaken. © 2014 Springer Science+Business Media New York.

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.

Agrimi G.,University of Bari | Russo A.,University of Bari | Scarcia P.,University of Bari | Palmieri F.,University of Bari | Palmieri F.,CNR Institute of Neuroscience
Biochemical Journal | Year: 2012

The essential cofactors CoA, FAD and NAD + are synthesized outside the peroxisomes and therefore must be transported into the peroxisomal matrix where they are required for important processes. In the present study we have functionally identified and characterized SLC25A17 (solute carrier family 25 member 17), which is the only member of the mitochondrial carrier family that has previously been shown to be localized in the peroxisomal membrane. Recombinant and purified SLC25A17 was reconstituted into liposomes. Its transport properties and kinetic parameters demonstrate that SLC25A17 is a transporter of CoA, FAD, FMN and AMP, and to a lesser extent of NAD + , PAP (adenosine 3′,5′-diphosphate) and ADP. SLC25A17 functioned almost exclusively by a counter-exchange mechanism, was saturable and was inhibited by pyridoxal 5′-phosphate and other mitochondrial carrier inhibitors. It was expressed to various degrees in all of the human tissues examined. Its main function is probably to transport free CoA, FAD and NAD + into peroxisomes in exchange for intraperoxisomally generated PAP, FMN and AMP. The present paper is the first report describing the identification and characterization of a transporter for multiple free cofactors in peroxisomes. ©The Authors Journal compilation ©2012 Biochemical Society.

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.

Esposito C.L.,CNR Institute of Neuroscience
Discovery medicine | Year: 2011

Nucleic acid-based aptamers have been shown as high-affinity ligands and potential antagonists of disease-associated proteins. Aptamers, isolated from combinatorial libraries by an iterative in vitro selection process, discriminate between closely related targets and are characterized by high specificity and low toxicity thus representing a valid alternative to antibodies to target specific proteins of biomedical interest. Moreover, they are non-immunogenic and can be easily stabilized by chemical modifications thus expanding their therapeutic potential. Here, we will focus on the structural and functional features of aptamers that have entered the clinical development pipeline together with those aptamers holding great potential as therapeutics in preclinical studies. The future perspectives of aptamers as therapeutics will be discussed as well.

Cabibbo G.,University of Palermo | Enea M.,University of Palermo | Attanasio M.,University of Palermo | Bruix J.,Barcelona Clinic Liver Cancer Group | And 3 more authors.
Hepatology | Year: 2010

Knowing the spontaneous outcome of hepatocellular carcinoma (HCC) is important for designing randomized controlled trials (RCTs) of new therapeutic approaches; however, survival of patients in the absence of treatment is highly variable, and prognostic factors influencing outcomes are incompletely defined. The aims of this meta-analysis were to estimate the 1-year and 2-year survival rates of untreated HCC patients enrolled in RCTs of palliative treatments, and to identify prognostic factors. RCTs evaluating therapies for HCC with placebo or no-treatment arms were identified on MEDLINE through April 2009. Data were combined in a random effect model. Primary outcomes were 1-year and 2-year survival. Thirty studies met the inclusion criteria. The pooled estimates of the survival rates were 17.5% at 1 year (95% confidence interval [95%CI], 11%-27%; range, 0%-75%) and 7.3% at 2 years (95%CI, 3.9%-13%; range, 0%-50%). Heterogeneity among studies was highly significant (P < 0.0001) both for 1-year and 2-year survival, and persisted when RCTs were stratified according to all patient and study features. Through meta-regression, impaired performance status, Child-Pugh B-C class, and presence of portal vein thrombosis were all independently associated with shorter survival. Ascites was strongly linked to a worse outcome in intermediate/advanced Barcelona Clinic Liver Cancer stages. Conclusion: This meta-analysis confirms the heterogeneity of behavior of untreated HCC and provides a sound basis for stratifying patients with HCC according to expected survival in future trials of new anti-cancer agents. Copyright © 2010 by the American Association for the Study of Liver Diseases.

Slussarenko S.,University of Naples Federico II | Murauski A.,Hong Kong University of Science and Technology | Du T.,Hong Kong University of Science and Technology | Chigrinov V.,Hong Kong University of Science and Technology | And 3 more authors.
Optics Express | Year: 2011

Using a photoalignment technique with a sulphonic azo-dye as the surfactant aligning material, we fabricated electrically tunable liquid crystal q-plates with topological charge 0.5, 1.5 and 3 for generating optical vortex beams with definite orbital angular momentum (OAM) 1,3 and 6 per photon (in units of h̄), respectively. We carried out several tests on our q-plates, including OAM tomography, finding excellent performances. These devices can have useful applications in general and quantum optics. © 2011 Optical Society of America.

Pulcini G.,CNR Institute of Neuroscience
Reliability Engineering and System Safety | Year: 2015

This note investigates the effect of the incorrect modeling of the failure process of minimally repaired systems that operates under random environmental conditions on the costs of a periodic replacement maintenance. The motivation of this paper is given by a recently published paper, where a wrong formulation of the expected cost for unit time under a periodic replacement policy is obtained. This wrong formulation is due to the incorrect assumption that the intensity function of minimally repaired systems that operate under random conditions has the same functional form as the failure rate of the first failure time. This produced an incorrect optimization of the replacement maintenance. Thus, in this note the conceptual differences between the intensity function and the failure rate of the first failure time are first highlighted. Then, the correct expressions of the expected cost and of the optimal replacement period are provided. Finally, a real application is used to measure how severe can be the economical consequences caused by the incorrect modeling of the failure process. © 2015 Elsevier Ltd. All rights reserved.

Di Porzio U.,CNR Institute of Neuroscience
Frontiers in Human Neuroscience | Year: 2016

Functional magnetic resonance imaging (fMRI) provides a powerful way to visualize brain functions and observe brain activity in response to tasks or thoughts. It allows displaying brain damages that can be quantified and linked to neurobehavioral deficits. fMRI can potentially draw a new cartography of brain functional areas, allow us to understand aspects of brain function evolution or even breach the wall into cognition and consciousness. However, fMRI is not deprived of pitfalls, such as limitation in spatial resolution, poor reproducibility, different time scales of fMRI measurements and neuron action potentials, low statistical values. Thus, caution is needed in the assessment of fMRI results and conclusions. Additional diagnostic techniques based on MRI such as arterial spin labeling (ASL) and the measurement of diffusion tensor imaging (DTI) provide new tools to assess normal brain development or disruption of anatomical networks in diseases. A cutting edge of recent research uses fMRI techniques to establish a “map” of neural connections in the brain, or “connectome”. It will help to develop a map of neural connections and thus understand the operation of the network. New applications combining fMRI and real time visualization of one’s own brain activity (rtfMRI) could empower individuals to modify brain response and thus could enable researchers or institutions to intervene in the modification of an individual behavior. The latter in particular, as well as the concern about the confidentiality and storage of sensitive information or fMRI and lie detectors forensic use, raises new ethical questions. © 2016 di Porzio.

The Yerer-Tullu Wellel Volcano-tectonic Lineament (YTVL) is an E-W trending fault system or aborted rift that intercepts the Main Ethiopian Rift (MER) at Debre Zeyt (Bishoftu)/Yerer, in the eastern periphery of Addis Ababa. The structure is in correspondence with the westward extension of the southern margin of the Gulf of Aden rift. The YTVL extends for more than 500 km with a very clear northern fault margin, between Addis Ababa and Ambo known as the "Ambo Fault". The southern margin is indicated by an E-W trending segmented lineaments at the latitude of about N 8°300', the Bedele-Metu being the most clear segment. In between these limits there are several evolved central volcanoes and cinder cones. The central volcanoes range in age from 12 to 7 Ma in the western most (Tullu Wellel) and gradually the upper limit get younger towards East to less than 1 Ma in the Wenchi and Debre Zeyt (Bishoftu) areas. These volcanic products cover the whole spectrum of a continental rift volcanic rocks suite: (1) in the eastern zone (Yerer-Bishoftu) the suite is silica over-saturated, ranging in composition from transitional basalt to peralkaline rhyolite, (2) moving westwards, between Wechacha and Wenchi, the rocks suite is silica saturated ranging in composition from alkali basalt to trachyte, (3) further West between Ijaji- Konchi and Nekemt the rocks suite is silica under-saturated ranging in composition from basanite to phonolite. Crossing the Dedessa lineament, the Tullu Wellel rocks appear to be silica saturated. Within a single suite fractional crystallization is the predominant evolutional process even in the silica over-saturated suite. The westwards progressive silica under-saturation and increase in alkalinity (except for the Tullu Wellel volcanic centers) is interpreted by the gradual deepening of an anomalous mantle where partial fusion took place. Therefore, as distance increases from the MER junction to the West, the amount of melt on the upper mantle was gradually reduced and became more alkaline but poorer in silica. © 2014 Elsevier Ltd.

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.

Moramarco T.,CNR Institute of Neuroscience | Singh V.P.,Texas A&M University
Journal of Hydrologic Engineering | Year: 2010

The linear entropic relation between mean flow velocity ū and maximum velocity umax is defined through a dimensionless entropy parameter M, which is found constant for gauged river sections. This entropic relation has been tested for many rivers and has been found to be fundamental to addressing velocity measurements during high floods when sampling can be carried out only in the upper portion of flow area where the maximum velocity umax occurs. It is therefore of considerable interest to investigate the possible dependence of M on hydraulic and geometric characteristics so that it can be determined for ungauged river sites. Thus, this study attempts to define the dependence of M on the geometric and hydraulic characteristics of river cross sections by coupling Manning's equation expressing ū with the equation for umax obtained through a logarithmic velocity distribution, which takes into account the possibility that umax may occur below the water surface. Analysis shows that M does not depend on the energy or water surface slope Sf, thus justifying why its mean value at a gauged site is always nearly the same, whatever the flood condition. Moreover, the hydraulic and geometric characteristics that permit the determination of M mainly include Manning's roughness, hydraulic radius, and locations where umax occurs and the hypothetical zero velocity. Then, a formulation relating Manning's roughness to M is proposed. Velocity measurements carried out in the past 20 years at two gauged sections along the Tiber River, Italy are used to test the analysis. © 2010 ASCE.

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.

Bruno D.,CNR Institute of Neuroscience | Giovangigli V.,Ecole Polytechnique - Palaiseau
Physics of Fluids | Year: 2011

We investigate the relaxation of internal temperature and the concept of volume viscosity in nonequilibrium gas models derived from the kinetic theory. We first investigate a nonequilibrium gas model with two temperatures-translational and internal-where the volume viscosity is absent. We establish that in a relaxation regime, the temperature difference becomes proportional to the divergence of the velocity fields and define a nonequilibrium, multitemperature, volume viscosity coefficient. We next analyze the convergence of the two temperature model towards the one temperature model when the relaxation is fast. We then investigate a nonequilibrium two temperature gas model with a fast and a slow internal energy mode. We establish that in a relaxation regime, there are four contributions to the volume viscosity, namely, the fast internal mode volume viscosity, the slow internal mode volume viscosity, the relaxation pressurethe perturbed source term. In the thermodynamic equilibrium limit, the sum of these four terms converges toward the one-temperature two-mode volume viscosity. We finally perform Monte Carlo simulations of spontaneous fluctuations near thermodynamic equilibrium. The numerical results obtained from the Boltzmann equation are compared to the predictions of the one and two temperature fluid modelsthe agreement between theory and calculations is complete. © 2011 American Institute of Physics.

Crescenzi M.,CNR Institute of Neuroscience
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.

Riccio A.,The Second University of Naples | Riccio A.,CNR Institute of Neuroscience | Cubellis M.V.,University of Naples Federico II
Nature Genetics | Year: 2012

Loss-of-function mutations in the gene encoding the cyclin-dependent kinase inhibitor CDKN1C cause Beckwith-Wiedemann syndrome and cancer. A new study now identifies potentially gain-of-function missense mutations in CDKN1C that cause the undergrowth-associated IMAGe syndrome. © 2012 Nature America, 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).

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.

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.

Harwood C.,CNR Institute of Neuroscience | Turner L.,EKCO Hand Therapy
Journal of Hand Surgery: European Volume | Year: 2016

Midcarpal instability is a complex condition that can present in various forms, from mild pain to debilitating subluxation. Once diagnosed, treatment guidelines for hand therapy are limited by the scarcity of high-level evidence. Evidence does exist for use of proprioceptive awareness and neuromuscular rehabilitation for instability of the knee, shoulder and ankle joint, but studies of similar programmes for the wrist joint have not been published. The purpose of this review is to examine the evidence supporting current concepts in the non-operative management of midcarpal instability, and to provide recommendations for the management of this condition with hand therapy. © The Author(s) 2015.

Crunelli V.,University of Cardiff | Carmignoto G.,CNR Institute of Neuroscience
Journal of Physiology | Year: 2013

Our current knowledge of the role of astrocytes in health and disease states supports the view that many physiological brain functions and neurological diseases are finely tuned, and in certain cases fully determined, by the continuous cross-talk between astrocytes and neurons. This novel way of interpreting brain activity as a dynamic and reciprocal interplay between astrocytic and neuronal networks has also influenced our understanding of epilepsy, not only forcing a reinterpretation of old findings, but also being a catalyst for novel experimentation. In this review, we summarize some of the recent studies that highlight these novel distinct contributions of astrocytes to the expression of convulsive and non-convulsive epileptiform discharges and seizures. The emerging picture suggests a general framework based on bilateral signalling between astrocytes and neurons for a fuller understanding of epileptogenic and epileptic mechanisms in the brain network. Astrocytes potentially represent targets for the development of those novel chemical entities with improved efficacy for the treatment of convulsive and non-convulsive epilepsy that expert groups have recognized as one of the key priorities for the management of epilepsy. © 2013 The Physiological Society.

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.

Maresi G.,Center for Technology Transfer | Oliveira Longa C.M.,Research and Innovation Center | Turchetti T.,CNR Institute of Neuroscience
IForest | Year: 2013

The quality and quantity of nut production are fundamental to the economic viability of chestnut cultivation, yet recent reports indicate that severe damage due to moulds represents a significant problem for growers. We carried out an investigation of the agents of chestnut rot and internal fruit damage in three orchards in Italy. Black and brown rot, as well as insect damage, were found in all the areas examined. Brown rot appeared to be the main cause of damage, affecting 8% to 49% and 2% to 24% of nuts collected from the ground and from burrs, respectively. With respect to morphology and DNA sequencing analyses, fungal isolates obtained from brown rot were homologous with Gnomoniopsis sp. obtained from Dryocosmus kuriphilus (Yasumatsu) galls and with Gnomoniopsis castanea and Gnomoniopsis smithogilvyi described on chestnut in Italy and Australia, respectively. The same fungus was also isolated from the bark of one- and two-years-old healthy shoots at each site, supporting the endophytic behaviour of this rot agent. Brown rot symptoms on nuts associated with Gnomoniopsis sp. corresponded with those previously described by several authors and referred to as Phoma or Phomopsis endogena, suggesting a relationship between these fungi and Gnomoniopsis sp. It is to notice that the escalation of brown rot damage in Italy followed several periods of drought and probably the recent invasion of D. kuriphilus, both stress factors for chestnut trees. © iForest - Biogeosciences and Forestry.

Ferrero F.,Polytechnic University of Turin | Tonetti C.,CNR Institute of Neuroscience | Periolatto M.,Polytechnic University of Turin
Carbohydrate Polymers | Year: 2014

A chitosan-coated cotton gauze was prepared by UV-curing and tested as adsorbent to remove copper (II) and chromium (VI) ions from water solutions. The adsorbent characterization was carried out by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDX) and Fourier Transform Infrared Spectroscopy in Attenuated Total Reflection (FTIR-ATR). Adsorption of copper and chromium ions onto the gauze was tested in batch process at different experimental conditions. The effects of pH, temperature, contact time and metal ion concentration were investigated. The optimum adsorption took place at pH 3 for Cr(VI) and pH 5 for Cu(II) ions respectively, while the temperature did not affect the adsorption process. Pseudo-first and pseudo-second order models were used to investigate the adsorption kinetics which was found very fast and better described by the pseudo-second order model for both metal ions. The adsorption of Cr(VI) ions was satisfactory described by the Langmuir isotherm, while that of Cu(II) ions showed a better agreement with the Freundlich model. © 2014 Elsevier Ltd.

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.

Fillion-Gourdeau F.,University of Montreal | Herrmann H.J.,ETH Zurich | Mendoza M.,ETH Zurich | Palpacelli S.,Numidia S.R.L. | 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.

Brambilla G.,CNR Institute of Neuroscience | Maffei L.,The Second University of Naples
Noise Control Engineering Journal | Year: 2010

In the last decade many improvements and large applications of noise control techniques have been observed, as well as enforcement and implementation of noise legislation at national and international levels. Notwithstanding, noise in urban areas has not decreased as expected and reductions in noise levels do not necessarily lead to a better acoustic comfort in urban areas. This has increased the concern of stakeholders (population, politicians, decision makers,...) and their awareness of the harmful effects of noise. The soundscape approach, concentrating on the way that people consciously perceive their environment (namely the interactions between people and sounds), might open novel perspectives and provide further insights towards fighting noise. In this approach, complementary to the noise control engineering techniques, the participation of people is fundamental along with their involvement that complies with the requirements issued by the European directive on the assessment and management of environmental noise. This paper provides an overview of some experimental studies carried out in the field and laboratory, dealing with urban areas of Naples and Rome with particular features (historical sites, outdoor markets, pedestrian areas, tourist attractions). Noise measurements and interviews of people by questionnaires have been used to investigate the sonic environment and its influence on the recognition and quality of a urban site by the users. A laboratory procedure based on virtual scenarios accompanied by visual and audio stimuli is presented and its potential as urban design tool is discussed. © 2010 Institute of Noise Control Engineering.

Perali A.,University of Camerino | Neilson D.,University of Camerino | Neilson D.,CNR Institute of Neuroscience | Hamilton A.R.,University of New South Wales
Physical Review Letters | Year: 2013

Exciton bound states in solids between electrons and holes are predicted to form a superfluid at high temperatures. We show that by employing atomically thin crystals such as a pair of adjacent bilayer graphene sheets, equilibrium superfluidity of electron-hole pairs should be achievable for the first time. The transition temperatures are well above liquid helium temperatures. Because the sample parameters needed for the device have already been attained in similar graphene devices, our work suggests a new route toward realizing high-temperature superfluidity in existing quality graphene samples. © 2013 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.

Di Giulio M.,CNR Institute of Neuroscience
Journal of Molecular Evolution | Year: 2015

I present a model for the evolution of the genetic code that seems to predict, in a totally natural way, the origin of the first mRNAs. In particular, the model—bestowing to peptidated-RNAs the major catalytic role in the phase that triggered the genetic code origin—suggests that interactions between peptidated-RNAs led to the synthesis of these ancestral catalysts. Within every group of these interactions, a pre-mRNA molecule evolved that was able to direct all interactions between peptidated-RNAs of that particular group. This represented an improvement in the coding of these interactions compared to the interaction groups that did not evolve these pre-mRNAs. This would represent a natural and intrinsic tendency. Therefore, these molecules of pre-mRNAs were positively selected because they improved the synthesis of the catalysts through this first form of coding of interactions among peptidated-RNAs. Thus, according to the model were the pairings—involving a base number greater than three (ennuplet code)—between peptidated-RNAs and pre-mRNAs that would represent the first form of the genetic code. The evolution of this ennuplet code to the triplet code might have been simply triggered by the natural tendency to make the reading module—that is the interactions between peptidated-RNAs and pre-mRNAs—of the different ennuplets to the triplet uniform, because in this way the heterogeneity existing in interactions between the aminoacylated or peptidated-RNAs and pre-mRNAs was eliminated. That is to say, there might have been the natural tendency toward the triplets because these would have made these interactions more efficient, given that the ennuplets were at least more cumbersome and therefore less economic and with an inferior adaptive value; and also because the triplets would represent the simpler choice among that available given that the doublets would have codified too few meanings and quartets instead too many. Therefore, the genetic code would result from a very long era of interactions among peptidated-RNAs under the continuous and fundamental selective pressure for improving catalysts’ syntheses and thus catalysis. The model is strongly corroborated by the explanation that the tmRNA molecule (transfer-messenger RNA) would seem to be the very molecule of pre-mRNAs that the model predicts. In other words, the tmRNA would be the molecular fossil of the evolutionary stages that led to the appearance of the first mRNAs. © 2015, Springer Science+Business Media New York.

Efremov D.G.,CNR Institute of Neuroscience | Laurenti L.,Catholic University Hospital melli
Expert Opinion on Investigational Drugs | Year: 2011

Introduction: The B-cell receptor (BCR) delivers antigen-dependent and -independent signals that have been implicated in the pathogenesis of several common B-cell malignancies. Agents that can efficiently block BCR signaling have recently been developed and are currently being evaluated as novel targeted therapies. Among these, agents that inhibit the Syk kinase appear particularly promising in preclinical and early clinical studies. Areas covered: The manuscript provides an overview of recent findings that implicate Syk and the BCR signaling pathway in the pathogenesis of several common lymphoid malignancies. It outlines preclinical and early clinical experiences with the Syk inhibitor fostamatinib disodium (R788) and discusses various options for further clinical development of this compound. Expert opinion: Inhibitors of Syk or other components of the BCR signaling pathway are emerging as an exciting novel class of agents for the treatment of common B-cell malignancies. Future efforts should focus on defining the disease entities that are most likely to benefit from these agents, although considerable evidence is already available to pursue such studies in patients with chronic lymphocytic leukemia. Combinations with chemo-immunotherapy, treatment of early-stage disease and consolidation therapy should all be explored and could lead to the development of novel therapeutic approaches with improved efficacy, tolerability and toxicity profiles. © 2011 Informa UK, Ltd.

Aubry A.,CNR Institute of Neuroscience | De Maio A.,University of Naples Federico II | Jiang B.,University of Minnesota | Zhang S.,University of Minnesota
IEEE Transactions on Signal Processing | Year: 2013

In this paper, we propose a cognitive approach to design phase-only modulated waveforms sharing a desired range-Doppler response. The idea is to minimize the average value of the ambiguity function of the transmitted signal over some range-Doppler bins, which are identified exploiting a plurality of knowledge sources. From a technical point of view, this is tantamount to optimizing a real and homogeneous complex quartic order polynomial with a constant modulus constraint on each optimization variable. After proving some interesting properties of the considered problem, we devise a polynomial-time waveform optimization procedure based on the Maximum Block Improvement (MBI) method and the theory of conjugate-partial-symmetric/conjugate-super-symmetric fourth order tensors. At the analysis stage, we assess the performance of the proposed technique showing its capability to properly shape the range-Doppler response of the transmitted waveform. © 2013 IEEE.

Spinozzi E.,University of Rome La Sapienza | Ciattoni A.,CNR Institute of Neuroscience
Optical Materials Express | Year: 2011

We predict that a liquid crystal/silver nanoparticles mixture can be designed so that its effective ordinary and extraordinary permittivities have, in a frequency range, real parts of different signs. We exploit this result to design an optical switch obtained by sandwiching a few hundred nanometers thick slab of the proposed mixture between two silica layers. By resorting to full-wave simulations, we show that, by varying the direction of an externally applied electric field, the transmissivity of the structure can be switched between 0.02 and 0.4 at a wavelength close to the frequency range where the medium is indefinite. The device functionality physically stems from the fact the orientation of the hyperbola characterizing extraordinary waves within the indefinite medium follows the applied electric field direction and therefore, if the hyperbola asymptote is nearly normal to the slab, full switch between evanescent and homogeneous propagating waves can be achieved within the medium. © 2011 Optical Society of America.

Ciferri A.,CNR Institute of Neuroscience
Polymer Chemistry | Year: 2013

A brief highlight of the structural features of self-healing polymers and of polymers healing under thermal, mechanical and chemical treatments is presented. A new healing mechanism is proposed for composite networks, based on the dissipation of constraints that hinder free fluctuation of network junctions. The model is supported by published experimental data for the stress-strain behavior of composite networks and by current elaborations of the molecular theory of network elasticity. The elimination of defects and steric constraints among the chains is regarded as a structural self-healing process also occurring in the case of reversible, self-assembling networks. © 2013 The Royal Society of Chemistry.

Obertegger U.,Research and Innovation Center | Manca M.,CNR Institute of Neuroscience
Journal of Limnology | Year: 2011

Information based on taxon-based indices is species-specific while information gained from function-based research can give a comprehensive view of ecosystem processes. We applied the guild-ratio, an index based on the proportion of functional groups of rotifers (i.e. microphagous and raptorial species), on a long-term data set of Lago Maggiore. By applying seasonal trend decomposition based on smoothing techniques and non-metrical multidimensional scaling, we assessed the response of rotifer functional groups to changes in trophic state and climate. While the taxon-based indices showed smooth changes, the function-based index showed a dramatic shift from a raptorial to a microphagous dominance, with a back-shift to raptorial dominance starting in 2000. The seasonal peak of microphagous and raptorial dry weight was clearly separated in the pre-eutrophication period. When mesotrophic conditions prevailed both peaks overlapped, only to be separated again with re-oligotrophication. We attributed these alterations of rotifer functional groups to changes in competition with crustacean zooplankton and to decreased phytoplankton algal abundance and size while altered seasonality in functional groups could be related to inter-group competition for food. We hypothesise that the effects of trophic state (i.e. altered phytoplankton) and climate (i.e. altered cladoceran community) were transferred across trophic levels to rotifer functional groups. Our study highlights that functional groups are valid instruments for illustrating unifying principles in ecology through a better understanding of ecosystem processes and the interrelationship between trophic levels.

Coccia M.,CNR Institute of Neuroscience | Coccia M.,Georgia Institute of Technology
Technovation | Year: 2012

The study here analyzes the association between R&D expenditure (as % of GDP) and labor productivity across leading geo-economic players. Empirical evidence seems to show, during the period of analysis, a strong positive association between public and private R&D expenditure. In addition, when R&D spending of business enterprise sector exceeds R&D spending of government sector, the labor productivity tends to growth (economic optimization), ceteris paribus. In general, effects of friction (inertia) on labor productivity growth are displayed by countries whose R&D intensity is driven mainly by R&D expenditure of government sector. Results provide fruitful implications that can support a rational political economy of R&D in order to foster the competitiveness of countries in fast-changing and turbulent markets. © 2012 Elsevier Ltd. All rights reserved.

Piccarreta M.,dellUniversita e della Ricerca | Lazzari M.,CNR Institute of Neuroscience | Pasini A.,CNR Institute of Atmospheric Pollution Research
International Journal of Climatology | Year: 2015

Changes in annual and seasonal temperatures were studied from 18 stations, distributed all over the Basilicata region (southern Italy), for the 1951-2010 period. The analysis is based on high-quality and homogenous daily minimum and maximum temperatures. Both minimum (Tmin) and maximum (Tmax) temperatures increase, especially after 1971. Seasonal results show upward trends in Tmin in winter, spring and summer, whereas they show downward trends in Tmin in autumn, especially in the last normal 1981-2010. Tmax also shows upward trends in spring and summer, whereas it tends to decrease during winter and autumn. The intra-annual extreme temperature range (ETR) index also shows a general positive trend, especially during spring. Eleven indices were used to assess the changes in both the cold and warm tails of the daily temperature distribution. The presence of trends was assessed by means of the Mann-Kendall test. The results reveal a general upward tendency on warm days (TX90), warm nights (TN90) and tropical nights (T20) especially because of an increase in temperature after 1971. This datum is fully confirmed in summer which is the season mainly responsible for this trend. The annual occurrence of summer days (SU) and very warm days (TX99) is weakly increasing. The majority of cold extremes, i.e. very cold nights (TN1), cold days (TX10), cold nights (TN10), frost days (FD) and ice days (ID) showed negative trends, thus confirming the overall warming trend in the Basilicata region. This negative trend could stem from the strong increase of Tmin during winter, spring and summer. © 2015 Royal Meteorological Society.

Naghsh M.M.,Isfahan University of Technology | Soltanalian M.,Uppsala University | Stoica P.,Uppsala University | Modarres-Hashemi M.,Isfahan University of Technology | And 2 more authors.
IEEE Transactions on Signal Processing | Year: 2014

In this paper, we study the joint design of Doppler robust transmit sequence and receive filter to improve the performance of an active sensing system dealing with signal-dependent interference. The signal-to-noise-plus- interference (SINR) of the filter output is considered as the performance measure of the system. The design problem is cast as a max-min optimization problem to robustify the system SINR with respect to the unknown Doppler shifts of the targets. To tackle the design problem, which belongs to a class of NP-hard problems, we devise a novel method (which we call DESIDE) to obtain optimized pairs of transmit sequence and receive filter sharing the desired robustness property. The proposed method is based on a cyclic maximization of SINR expressions with relaxed rank-one constraints, and is followed by a novel synthesis stage. We devise synthesis algorithms to obtain high quality pairs of transmit sequence and receive filter that well approximate the behavior of the optimal SINR (of the relaxed problem) with respect to target Doppler shift. Several numerical examples are provided to analyze the performance obtained by DESIDE. © 1991-2012 IEEE.

Zoratti M.,CNR Institute of Neuroscience
Anti-cancer agents in medicinal chemistry | Year: 2014

Plant polyphenols exhibit potentially useful effects in a wide variety of pathophysiological settings. They interact with proteins such as signalling kinases, transcription factors and ion channels, and modulate redox processes, such as those taking place in mitochondria. Biomedical applications of these natural compounds are however severely hindered by their low bioavailability, rapid metabolism, and often by unfavourable physico-chemical properties, e.g. a generally low water solubility. Derivatives are under development with the aim of improving their bioavailability and/or bioefficacy. Various strategies can be adopted. An increase in circulating blood levels of non-metabolized natural compound may be attainable through prodrugs. In the ideal prodrug, phenolic hydroxyls are protected by capping groups which a) help or at least do not hinder permeation of epithelia; b) prevent conjugative modifications during absorption and first-pass through the liver; c) are eliminated with opportune kinetics to regenerate the parent compound. Moreover, prodrugs may be designed with the goals of modulating physical properties of the parent compound, and/or changing its distribution in the body. A more specific action may be achieved by concentrating the compounds at specific sites of action. An example of the second approach is represented by mitochondria-targeted redox-active polyphenol derivatives, designed to intervene on radical processes in these organelles and as a tool either to protect cells from oxidative insults or to precipitate their death. Mitochondrial targeting can be achieved through conjugation with a triphenylphosphonium lipophilic cation. Quercetin and resveratrol were chosen as model polyphenols for these proof-of-concept studies. Data available at the moment show that both quercetin and resveratrol mitochondria-targeted derivatives are pro-oxidant and cytotoxic in vitro, selectively killing fast-growing and tumoural cells when supplied in the low μM range; the mechanism of ROS generation appears to differ between the two classes of compounds. These approaches are emerging as promising strategies to obtain new efficient chemopreventive and/or chemotherapeutic drugs based on polyphenols derivatives.

Maya-Vetencourt J.F.,Normal School of Pisa | Origlia N.,CNR Institute of Neuroscience
Neural Plasticity | Year: 2012

The central nervous system architecture is highly dynamic and continuously modified by sensory experience through processes of neuronal plasticity. Plasticity is achieved by a complex interplay of environmental influences and physiological mechanisms that ultimately activate intracellular signal transduction pathways regulating gene expression. In addition to the remarkable variety of transcription factors and their combinatorial interaction at specific gene promoters, epigenetic mechanisms that regulate transcription have emerged as conserved processes by which the nervous system accomplishes the induction of plasticity. Experience-depenDent changes of DNA methylation patterns and histone posttranslational modifications are, in fact, recruited as targets of plasticity-associated signal transduction mechanisms. Here, we shall concentrate on structural and functional consequences of early sensory deprivation in the visual system and discuss how intracellular signal transduction pathways associated with experience regulate changes of chromatin structure and gene expression patterns that unDerlie these plastic phenomena. Recent experimental eviDence for mechanisms of cross-modal plasticity following congenital or acquired sensory deprivation both in human and animal models will be consiDered as well. We shall also review different experimental strategies that can be used to achieve the recovery of sensory functions after long-term deprivation in humans. © Copyright 2012 José Fernando Maya-Vetencourt and Nicola Origlia.

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.

Kowalczyk M.,Polish Academy of Sciences | Piorkowska E.,Polish Academy of Sciences | Kulpinski P.,Technical University of Lodz | Pracella M.,CNR Institute of Neuroscience
Composites Part A: Applied Science and Manufacturing | Year: 2011

A novel composite material containing 2 wt% of cellulose nanofibers well dispersed in PLA matrix, both materials being biodegradable, was prepared and studied. Biodegradable composites with 2 and 20 wt% of cellulose fibers with standard diameters were also obtained and examined for comparison. The nanocomposite exhibited markedly higher storage modulus as compared to neat PLA and the composite with the same content of cellulose standard fibers. In addition, yield strength of the nanocomposite was improved in comparison with neat PLA, especially at elevated temperature of 45 °C, at which it was higher by 50%. No negative effect of standard fibers and nanofibers on molar mass of PLA matrix was observed. Moreover, the composite materials, including the nanocomposite, did not show weight loss up to 300 °C. © 2011 Elsevier Ltd. All rights reserved.

Koops K.,University of Zurich | Visalberghi E.,CNR Institute of Neuroscience | van Schaik C.P.,University of Zurich
Biology letters | Year: 2014

Tool use in extant primates may inform our understanding of the conditions that favoured the expansion of hominin technology and material culture. The 'method of exclusion' has, arguably, confirmed the presence of culture in wild animal populations by excluding ecological and genetic explanations for geographical variation in behaviour. However, this method neglects ecological influences on culture, which, ironically, may be critical for understanding technology and thus material culture. We review all the current evidence for the role of ecology in shaping material culture in three habitual tool-using non-human primates: chimpanzees, orangutans and capuchin monkeys. We show that environmental opportunity, rather than necessity, is the main driver. We argue that a better understanding of primate technology requires explicit investigation of the role of ecological conditions. We propose a model in which three sets of factors, namely environment, sociality and cognition, influence invention, transmission and retention of material culture. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Coccia E.,University of LAquila | Varsano D.,CNR Institute of Neuroscience | Guidoni L.,University of LAquila
Journal of Chemical Theory and Computation | Year: 2014

In this letter, we report the singlet ground state structure of the full carotenoid peridinin by means of variational Monte Carlo (VMC) calculations. The VMC relaxed geometry has an average bond length alternation of 0.1165(10) Å, larger than the values obtained by DFT (PBE, B3LYP, and CAM-B3LYP) and shorter than that calculated at the Hartree-Fock (HF) level. TDDFT and EOM-CCSD calculations on a reduced peridinin model confirm the HOMO-LUMO major contribution of the Bu+-like (S2) bright excited state. Many Body Green's Function Theory (MBGFT) calculations of the vertical excitation energy of the Bu+-like state for the VMC structure (VMC/MBGFT) provide an excitation energy of 2.62 eV, in agreement with experimental results in n-hexane (2.72 eV). The dependence of the excitation energy on the bond length alternation in the MBGFT and TDDFT calculations with different functionals is discussed. © 2014 American Chemical Society.

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.

Cossu A.,CNR Institute of Neuroscience
European Journal of Cancer Prevention | Year: 2016

The aim of this report was to study the descriptive and genetic epidemiology of malignant melanoma in North Sardinia, Italy, in the period 1992–2011. Epidemiological data were obtained from the local tumor registry, which is part of the Italian Association for Tumor Registries. Among patients included in the North Sardinia tumor registry, 316 patients first evaluated for familial recurrence of melanoma were submitted to mutation analysis in CDKN2A and CDK4 genes. The overall number of cases registered was 532. The male-to-female ratio was 1 : 1 and the mean age was 56 years for men and 55 years for women. The standardized incidence rates were 4.9/100 000 and 4.4/100 000 and the standardized mortality rates were 1.7/100 000 and 1.3/100 000 for men and women, respectively. The relative 5-year survival was 77% for men and 79% for women. In our series, 24/316 (7.6%) patients had a familial occurrence of melanoma (presence of at least one additional family member affected). Among these, one variant (Gly23Asp), reported previously as a low-frequency disease-causing mutation, was detected by mutational screening in the p16 gene only. With the exception of polymorphisms, none of either the sporadic melanoma patients or healthy controls presented a germline mutation in candidate genes. An increase in incidence and a decrease in mortality rates of malignant melanoma were registered in North Sardinia, from 1992 to 2011, whereas survival was similar to that reported in recent international reports. The high-penetrance melanoma susceptibility genes (CDKN2A and CDK4) are not involved in predisposition to melanoma in North Sardinia. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.

D'Agostino S.,University of Pavia | Della Sala F.,CNR Institute of Neuroscience | Della Sala F.,Italian Institute of Technology | Andreani L.C.,University of Pavia
Physical Review B - Condensed Matter and Materials Physics | Year: 2013

A theoretical control of the electromagnetic coupling between localized surface plasmons and pointlike sources of radiation is a relevant topic in nanoscience and nanophotonics. In this paper a numerical approach based on the discrete dipole approximation is presented as a practical and reliable computational tool to study the decay dynamics of a dipole when it is located in the near proximities of metallic nanoparticles whose shapes do not allow a fully analytical treatment. The method is first applied to Ag nanospheres and nanoshells, which represent two analytically solvable cases, and it is shown to lead to a very good agreement with exact results. The approach is then used to consider the response, in terms of perturbations induced on the radiative and nonradiative decay rates, of elongated nanoparticles, like Ag prolate spheroids and nanocones. Results demonstrate how the optical response of conically shaped nanoparticles can be affected by the distance and the orientation of the emitter of radiation, as well as by other geometrical parameters. The particular symmetry of these plasmonic objects results in peculiar features: the absorption efficiencies of the modes depend on the distance of the source of radiation in a counterintuitive way, and this is explained in terms of the excited charge density distributions. The possibility to simulate arbitrary-shaped nanostructures and several dipole-metal configurations presented here, could thus open new avenues for an aware use of surface plasmons in fluorescence spectroscopy applications or single photon emission studies. © 2013 American Physical 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.

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.

Colombo E.,San Raffaele Scientific Institute | Borgiani B.,San Raffaele Scientific Institute | Verderio C.,CNR Institute of Neuroscience | Furlan R.,San Raffaele Scientific Institute
Frontiers in Physiology | Year: 2012

Microvesicles (MVs) are released by most cell types in physiological conditions, but their number is often increased upon cellular activation or neoplastic transformation. This suggests that their detection may be helpful in pathological conditions to have information on activated cell types and, possibly, on the nature of the activation.This could be of paramount importance in districts and tissues that are not accessible to direct examination, such as the central nervous system. Increased release of MVs has been described to be associated to the acute or active phase of several neurological disorders. While the subcellular origin of MVs (exosome or ectosomes) is basically never addressed in these studies because of technical limitations, the cell of origin is always identified. Endothelium- or platelet-derived MVs, detected in plasma or serum, are linked to neurological pathologies with a vascular or ischemic pathogenic component, and may represent a very useful marker to support therapeutic choices in stroke. In neuroinflammatory disorders, such as multiple sclerosis, MVs of oligodendroglial, or microglial origin have been described in the cerebrospinal fluid and may carry, in perspective, additional information on the biological alterations in their cell of origin. Little specific evidence is available in neurodegenerative disorders and, specifically, MVs of neural origin have never been investigated in these pathologies. Few data have been reported for neuroinfection and brain trauma. In brain tumors, despite the limited number of studies performed, results are very promising and potentially close to clinical translation. We here review all currently available data on the detection of MVs in neurological diseases, limiting our search to exclusively human studies. Current literature and our own data indicate that MVs detection may represent a very promising strategy to gain pathogenic information, identify therapeutic targets, and select specific biomarkers for neurological disorders. © 2012 Colombo, Borgiani, Verderio and Furlan.

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.

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.

Milia A.,CNR Institute of Neuroscience | Torrente M.M.,University of Sannio | Bellucci F.,Contrada Nove Soldi 5G
Global and Planetary Change | Year: 2012

Vesuvius is an active volcano that has been affected by late Quaternary lateral collapses and tectonic faults. Cryptodomes and two debris avalanche, 18. ka-old DA1 and 3.5. ka-old DA2, were previously documented off Vesuvius and for the younger avalanche a link between onshore and offshore stratigraphy was reconstructed. The interpretation of seismic reflection profiles off Vesuvius, borehole stratigraphies, onshore and geomorphological data allowed to recognise the relationships among debris avalanches, criptodomes and faulting.Stratigraphic data reveal a remarkable difference between the architecture of the northern and southern volcano sectors that is compatible with the occurrence of the DA1 debris avalanche in the southern volcano sector. A contour map and a three-dimensional model of a surface merging the morphology of the top of the Somma lavas, in the northern volcano sector, with that of the top of the DA1 debris avalanche, in the southern volcano sector, were reconstructed. We present a new lateral collapse model of Vesuvius Volcano and document the relevance of inherited tectonic faults in guiding collapse geometry. It is possible that the SW-directed collapse (DA1) was driven towards the hangingwall blocks of NW-SE normal faults, while the propagation of the W-directed collapse (DA2) can be ascribed to the activity of the E-W strike-slip fault. Because of their distal location a minor role of cryptodome intrusion on collapses of Vesuvius can be postulated. The detailed analysis of substrate and edifice structure presented here establishes clear connexion between substrate tectonics and lateral collapse. This approach broadens the horizons of volcanic hazard assessment of Vesuvius. © 2011 Elsevier B.V.

Scotti N.,CNR Institute of Neuroscience | Rigano M.M.,University of Naples Federico II | Cardi T.,Italian Agricultural Research Council
Biotechnology Advances | Year: 2012

In the past decades, the progress made in plant biotechnology has made possible the use of plants as a novel production platform for a wide range of molecules. In this context, the transformation of the plastid genome has given a huge boost to prove that plants are a promising system to produce recombinant proteins. In this review, we provide a background on plastid genetics and on the principles of this technology in higher plants. Further, we discuss the most recent biotechnological applications of plastid transformation for the production of enzymes, therapeutic proteins, antibiotics, and proteins with immunological properties. We also discuss the potential of plastid biotechnology and the novel tools developed to overcome some limitations of chloroplast transformation. © 2011 Elsevier Inc.

Belardi G.,CNR Institute of Neuroscience | Medici F.,University of Rome La Sapienza | Piga L.,University of Rome La Sapienza
Journal of Power Sources | Year: 2014

The aim of the work is the recovery by thermal treatment of manganese and zinc from a mixture of zinc-carbon and alkaline spent batteries, due to the different phase change temperatures of the metals. Activated charcoal, as a reductant of the zinc-bearing phases to metallic Zn, was added to the mixture that was heated in different atmospheres (air, nitrogen, carbon dioxide) at different temperatures and residence times. Characterization of the mixture and of the residues of thermal treatment was carried out by chemical analysis, thermogravimetric and differential thermal analysis, scanning electron microscope and X-ray diffraction and allowed to understand the mechanisms of reduction of zinc and to interpret the formation of different compounds during the process. Results show that recovery of 99% of Zn (grade 96%) at 1200 C and 97% of Zn (grade 99%) at 1000 C, are achieved in N2 at 30 min residence time. Recovery of Mn at 1200 C and 30 min residence time was around 90-100% (90% grade). These products are suitable, after refining, for production of new batteries or higher value-added products. The residue of the treatment, enriched in manganese oxide, could be used in the production of iron-manganese alloys. © 2013 Elsevier B.V. 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.

In our ongoing efforts to build a bridge between peptide chemistry and organic chemistry, we are currently investigating: (1) two types of intramolecular macrocyclization reactions in 3(10)-helical peptides, and (2) a peptido[2]rotaxane molecular machine as a supramolecular tool using a 3(10)-helical peptide as the axle. More specifically, we studied the following two reactions: (a) the intramolecular ring-closing olefin metathesis between two amino acid residues with side chains bearing an allyl group, and (b) the intramolecular Paternò-Yang photoreaction, using a benzophenone-based amino acid as a photoaffinity reagent for a Met residue. Both reactions involve formation of a new C--C bond. As for the supramolecular system examined, we were able to identify the two stations of a new peptido[2]rotaxane characterized by an -(Aib)(6)- axle and to reversibly switch the aromatic tetramide macrocyclic wheel from one station to the next. This article summarizes the information available in the literature from other groups and the published/unpublished data originated from our laboratory on these research areas. 2010 Wiley Periodicals, Inc.

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.

Vitadello M.,CNR Institute of Neuroscience | Gherardini J.,University of Padua | Gorza L.,University of Padua
Antioxidants and Redox Signaling | Year: 2014

Aims: Redox and growth-factor imbalance fosters muscle disuse atrophy. Since the endoplasmic-reticulum chaperone Grp94 is required for folding insulin-like growth factors (IGFs) and for antioxidant cytoprotection, we investigated its involvement in muscle mass loss due to inactivity. Results: Rat soleus muscles were transfected in vivo and analyzed after 7 days of hindlimb unloading, an experimental model of muscle disuse atrophy, or standard caging. Increased muscle protein carbonylation and decreased Grp94 protein levels (p<0.05) characterized atrophic unloaded solei. Recombinant Grp94 expression significantly reduced atrophy of transfected myofibers, compared with untransfected and empty-vector transfected ones (p<0.01), and decreased the percentage of carbonylated myofibers (p=0.001). Conversely, expression of two different N-terminal deleted Grp94 species did not attenuate myofiber atrophy. No change in myofiber trophism was detected in transfected ambulatory solei. The absence of effects on atrophic untransfected myofibers excluded a major role for IGFs folded by recombinant Grp94. Immunoprecipitation and confocal microscopy assays to investigate chaperone interaction with muscle atrophy regulators identified 160 kDa neuronal nitric oxide synthase (nNOS) as a new Grp94 partner. Unloading was demonstrated to untether nNOS from myofiber subsarcolemma; here, we show that such nNOS localization, revealed by means of NADPH-diaphorase histochemistry, appeared preserved in unloaded myofibers expressing recombinant Grp94, compared to those transfected with the empty vector or deleted Grp94 cDNA (p<0.02). Innovation: Grp94 interacts with nNOS and prevents its untethering from sarcolemma in unloaded myofibers. Conclusion: Maintenance of Grp94 expression is sufficient to counter unloading atrophy and oxidative stress by mechanistically stabilizing nNOS-multiprotein complex at the myofiber sarcolemma. © 2014 Mary Ann Liebert, Inc.

Sheffer E.,Hebrew University of Jerusalem | von Hardenberg J.,CNR Institute of Neuroscience | Yizhaq H.,Ben - Gurion University of the Negev | Shachak M.,Ben - Gurion University of the Negev | Meron E.,Ben - Gurion University of the Negev
Ecology Letters | Year: 2013

In this article, we develop a unifying framework for the understanding of spatial vegetation patterns in heterogeneous landscapes. While much recent research has focused on self-organised vegetation the prevailing view is still that biological patchiness is mostly due to top-down control by the physical landscape template, disturbances or predators. We suggest that vegetation patchiness in real landscapes is controlled both by the physical template and by self-organisation simultaneously, and introduce a conceptual model for the relative roles of the two mechanisms. The model considers four factors that control whether vegetation patchiness is emerged or imposed: soil patch size, plant size, resource input and resource availability. The last three factors determine the plant-patch size, and the plant-to-soil patch size ratio determines the impact of self-organisation, which becomes important when this ratio is sufficiently small. A field study and numerical simulations of a mathematical model support the conceptual model and give further insight by providing examples of self-organised and template-controlled vegetation patterns co-occurring in the same landscape. We conclude that real landscapes are generally mixtures of template-induced and self-organised patchiness. Patchiness variability increases due to source-sink resource relations, and decreases for species of larger patch sizes. © 2012 Blackwell Publishing Ltd/CNRS.

Guzzi P.H.,University of Catanzaro | Cannataro M.,University of Catanzaro | Cannataro M.,CNR Institute of Neuroscience
BMC Bioinformatics | Year: 2010

Background: A main goal in understanding cell mechanisms is to explain the relationship among genes and related molecular processes through the combined use of technological platforms and bioinformatics analysis. High throughput platforms, such as microarrays, enable the investigation of the whole genome in a single experiment. There exist different kind of microarray platforms, that produce different types of binary data (images and raw data). Moreover, also considering a single vendor, different chips are available. The analysis of microarray data requires an initial preprocessing phase (i.e. normalization and summarization) of raw data that makes them suitable for use on existing platforms, such as the TIGR M4 Suite. Nevertheless, the annotations of data with additional information such as gene function, is needed to perform more powerful analysis. Raw data preprocessing and annotation is often performed in a manual and error prone way. Moreover, many available preprocessing tools do not support annotation. Thus novel, platform independent, and possibly open source tools enabling the semi-automatic preprocessing and annotation of microarray data are needed.Results: The paper presents μ-CS (Microarray Cel file Summarizer), a cross-platform tool for the automatic normalization, summarization and annotation of Affymetrix binary data. μ-CS is based on a client-server architecture. The μ-CS client is provided both as a plug-in of the TIGR M4 platform and as a Java standalone tool and enables users to read, preprocess and analyse binary microarray data, avoiding the manual invocation of external tools (e.g. the Affymetrix Power Tools), the manual loading of preprocessing libraries, and the management of intermediate files. The μ-CS server automatically updates the references to the summarization and annotation libraries that are provided to the μ-CS client before the preprocessing. The μ-CS server is based on the web services technology and can be easily extended to support more microarray vendors (e.g. Illumina).Conclusions: Thus μ-CS users can directly manage binary data without worrying about locating and invoking the proper preprocessing tools and chip-specific libraries. Moreover, users of the μ-CS plugin for TM4 can manage Affymetrix binary files without using external tools, such as APT (Affymetrix Power Tools) and related libraries. Consequently, μ-CS offers four main advantages: (i) it avoids to waste time for searching the correct libraries, (ii) it reduces possible errors in the preprocessing and further analysis phases, e.g. due to the incorrect choice of parameters or the use of old libraries, (iii) it implements the annotation of preprocessed data, and finally, (iv) it may enhance the quality of further analysis since it provides the most updated annotation libraries. The μ-CS client is freely available as a plugin of the TM4 platform as well as a standalone application at the project web site (http://bioingegneria.unicz.it/M-CS). © 2010 Guzzi and Cannataro; licensee BioMed Central Ltd.

Deramecourt V.,CNR Institute of Neuroscience
Revue Neurologique | Year: 2013

Cerebrovascular disease is an important cause of cognitive decline and dementia. Despite numerous epidemiological, clinical, neuroimaging and neuropathological studies, the link between cerebrovascular lesions and their impact on cognition and behavior is still a matter of debate. Cerebrovascular lesions are heterogeneous and most descriptive studies distinguish vessel wall modifications, perivascular space modifications, white matter changes, and infarcts as the main features of vascular dementia. However, to date there is still no consensual criteria for the neuropathological diagnosis of vascular or mixed dementia. The diagnosis of these conditions still relies on both clinical and neuropathological expertise. © 2013 Elsevier Masson SAS.

Salmilehto J.,Aalto University | Solinas P.,CNR Institute of Neuroscience | Mottonen M.,Aalto University
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2014

As quantum systems become more experimentally accessible, we are forced to reconsider the notions of control and work to fully account for quantum effects. To this end, we identify the work injected into a quantum system during a general quantum-mechanical driving protocol and quantify the relevant heat flows. The known results that are applicable in the limit of a classical drive are shown to emerge from our equations as a special case. Using the established framework, we show that the Bochkov-Kuzovlev identity for the exclusive work distribution is modified in a nontrivial way by the accumulation of system-drive correlations resulting from quantum back action. Our results accentuate the conceptual and discernible differences between a fully quantum-mechanical and classical driving protocols of quantum systems. © 2014 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.

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.

De Bernard M.,University of Padua | Rizzuto R.,CNR Institute of Neuroscience
EMBO Reports | Year: 2014

Mitochondrial Ca2+ uptake is a multifarious signal that controls both the activity of matrix dehydrogenases and the sensitivity to apoptotic and necrotic challenges. Recent evidence indicates that mitochondria also play a role in triggering inflammation, as mitochondrial DNA, when released by the cell, is an important damage-associated molecular pattern (DAMP). Now, Toll-like receptors (TLRs) are shown to close the loop, by affecting in turn mitochondrial activity. Two studies by Shintani and colleagues, one in this issue of EMBO reports, identify a new TLR transduction mechanism that impinges directly on mitochondrial function. Upon binding of CpG oligodeoxynucleotides, TLR9 - which in non-immune cells is retained in the ER - inhibits SERCA2, thus reducing Ca2+ transfer to the mitochondria and aerobic metabolism. TLR9 signaling in cardiomyocytes and neurons protects cells from stress-induced cell death by modulating energy metabolism. Upon ligand binding, TLR9 inhibits SERCA2 at the ER and thus Ca2+ handling to mitochondria, resulting in cell survival. © 2014 The Authors.

Xu H.,University of Michigan | Martinoia E.,University of Zurich | Szabo I.,University of Padua | Szabo I.,CNR Institute of Neuroscience
Cell Calcium | Year: 2015

Decades of intensive research have led to the discovery of most plasma membrane ion channels and transporters and the characterization of their physiological functions. In contrast, although over 80% of transport processes occur inside the cells, the ion flux mechanisms across intracellular membranes (the endoplasmic reticulum, Golgi apparatus, endosomes, lysosomes, mitochondria, chloroplasts, and vacuoles) are difficult to investigate and remain poorly understood. Recent technical advances in super-resolution microscopy, organellar electrophysiology, organelle-targeted fluorescence imaging, and organelle proteomics have pushed a large step forward in the research of intracellular ion transport. Many new organellar channels are molecularly identified and electrophysiologically characterized. Additionally, molecular identification of many of these ion channels/transporters has made it possible to study their physiological functions by genetic and pharmacological means. For example, organellar channels have been shown to regulate important cellular processes such as programmed cell death and photosynthesis, and are involved in many different pathologies. This special issue (SI) on organellar channels and transporters aims to provide a forum to discuss the recent advances and to define the standard and open questions in this exciting and rapidly developing field. Along this line, a new Gordon Research Conference dedicated to the multidisciplinary study of intracellular membrane transport proteins will be launched this coming summer. © 2015 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.

Tozzini V.,CNR Institute of Neuroscience
Accounts of Chemical Research | Year: 2010

(Figure Presented) The activity within a living cell is based on a complex network of interactions among biomolecules, exchanging information and energy through biochemical processes. These events occur on different scales, from the nano- to the macroscale, spanning about 10 orders of magnitude in the space domain and 15 orders of magnitude in the time domain. Consequently, many different modeling techniques, each proper for a particular time or space scale, are commonly used. In addition, a single process often spans more than a single time or space scale. Thus, the necessity arises for combining the modeling techniques in multiscale approaches. In this Account, I first review the different modeling methods for bio-systems, from quantum mechanics to the coarsegrained and continuum-like descriptions, passing through the atomistic force field simulations. Special attention is devoted to their combination in different possible multiscale approaches and to the questions and problems related to their coherent matching in the space and time domains. These aspects are often considered secondary, but in fact, they have primary relevance when the aim is the coherent and complete description of bioprocesses. Subsequently, applications are illustrated by means of two paradigmatic examples: (i) the green fluorescent protein (GFP) family and (ii) the proteins involved in the human immunodeficency virus (HIV) replication cycle. The GFPs are currently one of the most frequently used markers for monitoring protein trafficking within living cells; nanobiotechnology and cell biology strongly rely on their use in fluorescence microscopy techniques. A detailed knowledge of the actions of the virusspecific enzymes of HIV (specifically HIV protease and integrase) is necessary to study novel therapeutic strategies against this disease. Thus, the insight accumulated over years of intense study is an excellent framework for this Account. The foremost relevance of these two biomolecular systems was recently confirmed by the assignment of two of the Nobel prizes in 2008: in chemistry for the discovery of GFP and in medicine for the discovery of HIV. Accordingly, these proteins were studied with essentially all of the available modeling techniques, making them ideal examples for studying the details of multiscale approaches in protein modeling. © 2010 American Chemical Society.

Manca M.,CNR Institute of Neuroscience
Journal of Limnology | Year: 2011

Bythotrephes was first seen in North America in 1982 (single individual, Lake Ontario) and noticed elsewhere in the Laurentian Great Lakes in abundance in 1985. Starting from 1987 it sharply increased in the open-water zooplankton of Lago Maggiore, reaching values never recorded in the past 40 years. Despite being native, the species' impact on Lago Maggiore was somewhat comparable to that observed in invaded North American lakes. The re-emergence led to an overall increase in invertebrate predation which became permanent five years after Bythotrephes' establishment, causing direct and indirect effects on the food web. Changes included a sharp decrease in the large filter-feeder Daphnia, whose mortality rate increased, and consequently an increase in phytoplankton cell density; an increase in abundance and size of colonial rotifers with a decline in Leptodora abundance, and an overall decrease in zooplankton biomass were also observed. The increase of Bythotrephes in Lago Maggiore, however, was related to a shift in population phenology, which resulted in seasonal growth starting earlier and lasting longer. Daphnia phenology changed only later, suggesting that the impact was consequent to a temporary decoupling between Bythotrephes and its preferred prey. The shift in density and phenology became permanent. Over the long-term, however, potential competitors and prey were able to recover, reaching levels of abundance comparable to those recorded before the Bythotrephes' re-emergence. Such a response is likely attributable to behavioural adaptation mechanisms resulting in temporal and spatial displacement of potential competitors, predators and prey.

The recognition of inorganic materials by polypeptides is a technologically relevant and scientifically intriguing phenomenon. Several features of the polypeptide determine the affinity for a given surface and, possibly, its selectivity among a set of materials or among various crystal planes of the same material. Different amino acids have different intrinsic affinities for a given surface; the geometrical features of the surface are also relevant in the recognition process. By means of a minimal, analytically solvable thermodynamic model for the polypeptide-surface interaction, we discuss the role of the conformational flexibility in determining affinity and selectivity of polypeptides for surfaces. In particular, the interplay between geometrical matching of polypeptide-surface features and the presence in the polypeptide of amino acids able to bind the target surface is analyzed as a function of the flexibility. A discussion of literature data in the light of this minimal model is also given. © 2015, The Minerals, Metals & Materials Society.

Valenza G.,University of Pisa | Allegrini P.,CNR Institute of Neuroscience | Lanata A.,University of Pisa | Scilingo E.P.,University of Pisa
Frontiers in Neuroengineering | Year: 2012

In this work we characterized the non-linear complexity of Heart Rate Variability (HRV) in short time series. The complexity of HRV signal was evaluated during emotional visual elicitation by using Dominant Lyapunov Exponents (DLEs) and Approximate Entropy (ApEn). We adopted a simplified model of emotion derived from the Circumplex Model of Affects (CMAs), in which emotional mechanisms are conceptualized in two dimensions by the terms of valence and arousal. Following CMA model, a set of standardized visual stimuli in terms of arousal and valence gathered from the International Affective Picture System (IAPS) was administered to a group of 35 healthy volunteers. Experimental session consisted of eight sessions alternating neutral images with high arousal content images. Several works can be found in the literature showing a chaotic dynamics of HRV during rest or relax conditions. The outcomes of this work showed a clear switching mechanism between regular and chaotic dynamics when switching from neutral to arousal elicitation. Accordingly, the mean ApEn decreased with statistical significance during arousal elicitation and the DLE became negative. Results showed a clear distinction between the neutral and the arousal elicitation and could be profitably exploited to improve the accuracy of emotion recognition systems based on HRV time series analysis. © 2012 Valenza, Allegrini, Lanatà and Scilingo.

Di Profio G.,CNR Institute of Neuroscience | Curcio E.,University of Calabria | Drioli E.,University of Calabria
Industrial and Engineering Chemistry Research | Year: 2010

The interest to combine membrane operations and solution crystallization has grown in the past several years. This approach has been put into practice in several forms of membrane-assisted crystallization (MAC) processes, among which is membrane crystallization (MCr) technology. The main features of MCr are (1) the use of membranes as precision devices to control the composition of the crystallizing solution, by opposing a well-defined and tunable resistance to mass flow occurring in the vapor phase; (2) the action of the porous surface of the membrane as a suitable support to activate heterogeneous nucleation mechanisms; (3) the possibility to induce nucleation and crystal growth in separate sites, thus reducing the risk of membrane fouling even when the same membrane supports heterogeneous nucleation. Thanks to these fundamental options, combined together in a unique apparatus, advantages like (i) improved control of the supersaturation degree and the rate of its generation; (ii) the possibility for the crystallization to be initiated at low supersaturation levels; (iii) the enhancement of the crystallization kinetics; and (iv) improved overall process efficiency can be achieved, even for large and complex molecules like proteins. The most interesting developments and the more exciting perspectives for this novel technology have been reviewed in this paper. © 2010 American Chemical Society.

Pizzi G.,CNR Institute of Neuroscience | Virgilio M.,University of Pisa | Grosso G.,University of Pisa
Nanotechnology | Year: 2010

It is known that under a tensile strain of about 2% of the lattice constant, the energy of the bottom conduction state of bulk Ge at the Γ point falls below the minimum at the L point, leading to a direct gap material. In this paper we investigate how the same condition is realized in tensile strained Ge quantum wells. By means of a tight-binding sp3d 5s* model, we study tensile strained Ge/Si 0.2Ge0.8 multiple quantum well (MQW) heterostructures grown on a relaxed SiGeSn alloy buffer along the [001] direction. We focus on values of the strain fields at the crossover between the indirect and direct gap regime of the MQWs, and calculate band edge alignments, electronic band structures, and density of states. We also provide a numerical evaluation of the MQW material gain spectra for TE and TM polarization under realistic carrier injection levels, taking into account the leakages related to the occupation of the electronic states at the L point. The analysis of the different orbital contributions to the near-gap states of the complete structure allows us to give a clear interpretation of the numerical results for the strain-dependent TM/TE gain ratio. Our calculations demonstrate the effectiveness of the structures under consideration for light amplification. © 2010 IOP Publishing 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.

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.

Benassi A.,CNR Institute of Neuroscience | Benassi A.,CNR Institute for Energetics and Interphases | Zapperi S.,CNR Institute for Energetics and Interphases
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

Experimental investigations of the scaling behavior of Barkhausen avalanches in out-of-plane ferromagnetic films yield widely different results for the values of the critical exponents despite similar labyrinthine domain structures, suggesting that universality may not hold for this class of materials. Analyzing a phase-field model for magnetic reversal, we show that avalanche scaling is bounded by characteristic length scales arising from the competition between dipolar forces and exchange interactions. We compare our results with the experiments and find a good qualitative and quantitative agreement, reconciling apparent contradictions. Finally, we make some prediction, amenable to experimental verification, on the dependence of the avalanche's behavior from the film thickness and disorder. © 2011 American Physical Society.

Losurdo M.,CNR Institute of Neuroscience
Thin Solid Films | Year: 2011

This paper provides an overview of the relationship between optical ellipsometric measurements and nanoscale science. This relationship is discussed by analyzing published papers, patents and nanomaterials investigated in laboratories and constituting commercial products. Specific challenges and needs for advancing ellipsometry exploitation in nanotechnology are also discussed in the frame of nanometrology standardization. The ellipsometric characterization of plasmonic gold nanoparticles supported on a silicon substrate is used as an example to discuss various issues related to the optical characterization of nanomaterials, i.e., the detection of buried interfaces, size effects on the dielectric function and the monitoring in real time of nanoparticles growth. © 2010 Elsevier B.V. All rights reserved.

Fornasari D.,CNR Institute of Neuroscience
Clinical Drug Investigation | Year: 2012

The mechanisms involved in the development of chronic pain are varied and complex. Pain processes are plastic and unrelieved pain may lead to changes in the neural structure involved in pain generation. Nociceptive pain announces the presence of a potentially damaging stimulus that occurs when noxious stimuli activate primary afferent neurons. Neuropathic pain is initiated or caused by a primary lesion or dysfunction in the nervous system resulting from trauma, infection, ischaemia, cancer or other causes such as chemotherapy. The exact mechanisms involved in the pathophysiology of chronic pain are not well understood, but rapid and long-term changes are thought to occur in parts of the central nervous system that are involved in the transmission and modulation of pain following injury. Peripheral and central sensitization of sensory nerve fibres are the primary reasons for hypersensitivity to pain after injury, and mainly occur in inflammatory and neuropathic pain. During these processes the sensation of pain is enhanced as a result of changes in the environment, the nerve fibres and modifications of the functional properties and the genetic programme of primary and secondary afferent neurons. Non-steroidal anti-inflammatory drugs and opioid analgesics are two of the most common classes of drugs used for the treatment of pain. Response to drug treatment shows significant interindividual variability and can lead to side effects. The neurobiological mechanisms that cause pain may account for the different types of pain observed. Identification of these mechanisms may allow us to move from an empirical therapeutic approach to one that it is specifically targeted at the particular mechanisms of the type of pain experienced by an individual patient. © 2012 Adis Data Information BV. All rights reserved.

Shannon L.J.,University of Cape Town | Jarre A.C.,University of Cape Town | Petersen S.L.,CNR Institute of Neuroscience
Progress in Oceanography | Year: 2010

South Africa's commitment to implementation of the ecosystem approach to fishing (EAF) requires a solid scientific basis comprised of a toolkit assembled through concerted efforts from which management measures can be carefully considered and put into place. A series of workshops was held to assist in the identification of issues in South Africa's key fisheries that are cause for concern and may have EAF implications. Several of these issues were addressed under various projects. Food-web studies have been undertaken and models have been constructed of the changes in the structure and functioning of the Southern Benguela upwelling system. The combined effects of fishing and environmental change on South African fisheries have been examined using various observation-based and modelling methods. These are contributing to assessment of changes at multiple spatial and temporal scales, from the impact of pelagic fishing in key foraging areas of critically-dependent predators, to impacts of demersal trawls on the benthos and demersal fish assemblages, to decadal-scale dynamics, and global comparative classifications of ecosystem status. To address some of the EAF issues, practical implementation measures are being developed and applied in collaboration with stakeholders. Stakeholders are also actively involved in the process leading to development of indicators to address the human dimensions of EAF, and knowledge-based systems are being developed as decision support tools. Future priorities for South African EAF research will include placing more emphasis on conservation and biodiversity aspects, linking of environmental/oceanographic knowledge to management objectives, spatial aspects, as well as increased focus on the human dimension and transdisciplinary approaches. Indicators are a promising means of synthesizing multi-disciplinary information for consideration in the management process, providing measures of anthropogenic (including fishing) pressures including social and economic pressures, in combination with environmental drivers, and providing a means of assessing how these affect the Benguela ecosystem. Respectful scientific collaboration will be required to bridge the gap between classical single-species fisheries management approaches and broader ecosystem approaches. © 2010 Elsevier Ltd.

Glatz A.,Argonne National Laboratory | Varlamov A.A.,Argonne National Laboratory | Varlamov A.A.,CNR Institute of Neuroscience | Vinokur V.M.,Argonne National Laboratory
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

We revise the long-studied problem of fluctuation conductivity (FC) in disordered two-dimensional superconductors placed in a perpendicular magnetic field by finally deriving the complete solution in the temperature-magnetic field phase diagram. The obtained expressions allow both to perform straightforward (numerical) calculation of the FC surface δσxx(tot) (T,H) and to get asymptotic expressions in all its qualitatively different domains. This surface becomes in particular nontrivial at low temperatures, where it is trough-shaped with δσxx(tot)(T,H)<0. In this region, close to the quantum-phase transition, δσxx(tot)(T,H=const) is nonmonotonic, in agreement with experimental findings. We reanalyzed and present comparisons to several experimental measurements. Based on our results we derive a qualitative picture of superconducting fluctuations close to H c2(0) and T=0 where fluctuation Cooper pairs rotate with cyclotron frequency ωc∼ΔBCS-1 and Larmor radius ∼ξBCS, forming some kind of quantum liquid with long coherence length ξQFξBCS and slow relaxation (τQFΔBCS-1). © 2011 American Physical Society.

Meschke M.,Aalto University | Peltonen J.T.,Aalto University | Pekola J.P.,Aalto University | Giazotto F.,CNR Institute of Neuroscience
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

We present tunnel spectroscopy experiments on the proximity effect in lateral superconductor-normal-metal-superconductor Josephson junctions. Our weak link is embedded into a superconducting ring allowing phase biasing of the Josephson junction by an external magnetic field. We explore the temperature and phase dependence of both the induced minigap and the modification of the density of states in the normal metal. Our results agree with a model based on the quasiclassical theory in the diffusive limit. The device presents an advanced version of the superconducting quantum interference proximity transistor, now reaching flux sensitivities of 3 nA/Φ 0, where Φ 0 is the flux quantum. © 2011 American Physical Society.

Pan Y.,Fritz Haber Institute | Benedetti S.,CNR Institute of Neuroscience | Nilius N.,Fritz Haber Institute | Freund H.-J.,Fritz Haber Institute
Physical Review B - Condensed Matter and Materials Physics | Year: 2011

Monolayer films of MgO(001) have been prepared on an Au(111) surface and explored by means of scanning tunneling microscopy (STM) and spectroscopy. The symmetry mismatch between the hexagonal substrate and the squared overlayer results in the formation of a (6×1) superlattice, as revealed from the distinct stripe pattern observed in the STM images. The presence of the oxide film also modifies the potential situation at the interface, which induces a substantial upshift of the Shockley-type surface band on Au(111). The resulting MgO/Au interface band is characterized by a pseudogap at around 500 mV that opens at the position of the new Brillouin zone of the enlarged (6×1) unit cell. In addition the oxide layer gives rise to a drastic decrease of the Au(111) work function, as deduced from the energy position of the first field-emission resonance on the bare and MgO-covered surface. The work-function drop is explained by an interfacial charge transfer from the oxide film into the electro-negative gold surface. © 2011 American Physical Society.

Buffa A.,CNR Institute of Neuroscience | Harbrecht H.,University of Basel | Kunoth A.,University of Paderborn | Sangalli G.,University of Pavia
Computer Methods in Applied Mechanics and Engineering | Year: 2013

We consider elliptic PDEs (partial differential equations) in the framework of isogeometric analysis, i.e., we treat the physical domain by means of a B-spline or NURBS mapping which we assume to be regular. The numerical solution of the PDE is computed by means of tensor product B-splines mapped onto the physical domain. We construct additive multilevel preconditioners and show that they are asymptotically optimal, i.e., the spectral condition number of the resulting preconditioned stiffness matrix is independent of h. Together with a nested iteration scheme, this enables an iterative solution scheme of optimal linear complexity. The theoretical results are substantiated by numerical examples in two and three space dimensions. © 2013 Elsevier B.V.

Fierro A.,CNR Institute of Neuroscience
The European physical journal. E, Soft matter | Year: 2011

We construct a very simple epidemic model for influenza spreading in an age-class-distributed population, by coupling a lattice gas model for the population dynamics with a SIR stochastic model for susceptible, infected and removed/immune individuals. We use as a test case the age-distributed Italian epidemiological data for the novel influenza A(H1N1). The most valuable features of this model are its country-independent and virus-independent structure (few demographic, social and virological data are used to fix some parameters), its large statistic due to a very short run-time machine, and its easy generalizability to include mitigation strategies. In spite of its simplicity, the model presented reproduces the epidemiological Italian data, with sensible predictions for the reproduction number and theoretically interesting results for the generation time distribution.

Trapani A.,University of Bari | Palazzo C.,University of Bari | De Candia M.,University of Bari | Lasorsa F.M.,CNR Institute of Neuroscience | Trapani G.,University of Bari
Bioconjugate Chemistry | Year: 2013

The aim of the present review is to give a concise and updated analysis of the imaging tools for the visualization of activated microglia. After an overview on the important pathologies where activated microglia are involved, we first describe the role played by the translocator protein-18 kDa (TSPO) as an important target for the visualization of activated microglia. Second, imaging tools based on TSPO ligands radiolabeled for positron emission tomography (PET) are summarized with particular emphasis to the TSPO ligands alternative to the standard radioligand [11C]PK11195 or (R)-[11C]PK11195. In this regard, an updated list of 11C- and 18F-labeled TSPO radioligands is shown. Moreover, a detailed analysis based on TSPO ligands bearing fluorescent probes for fluorescence microscopy is also provided. This last optical imaging technique represents an area of large and increasing interest due to the advantages offered by the use of simple instrumentation and safer experimental conditions. The scope and limitations of the nuclear and optical imaging techniques are discussed. Finally, a perspective on the plausible advances in this area is also presented. © 2013 American Chemical Society.

Falavigna G.,CNR Institute of Neuroscience
Expert Systems with Applications | Year: 2012

On a wake of Basel II Accord in 2004, banks and financial institutions can build an internal rating system. This work focuses on Italian small firms that are more hard to judge because quite often financial data are not simply available. The aim of this paper is to propose a simulation model for assigning rating judgements to these firms, using poor financial information. The proposed model produces a simulated counterpart of Bureau van Dijk-K Finance (BvD) rating judgements. It is clear that there are problems when small firms must be judged because it is difficult to obtain financial data; indeed in Italy these enterprises must deposit the balance-sheet in reduced form. Suggested methodology is a three-layer process where each of them is formed by, respectively, one, two and four feed-forward artificial neural networks with back-propagation algorithm. The proposed model is a good solution for evaluating small firms with poor financial information but not only: the research underlines and supports the ability of artificial neural networks of learning and reproducing some aspects or some features or behaviours of reality. © 2011 Elsevier Ltd. All rights reserved.

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.

Nguyen N.L.,Ecole Polytechnique Federale de Lausanne | Borghi G.,Ecole Polytechnique Federale de Lausanne | Ferretti A.,CNR Institute of Neuroscience | Dabo I.,Pennsylvania State University | Marzari N.,Ecole Polytechnique Federale de Lausanne
Physical Review Letters | Year: 2015

The determination of spectral properties from first principles can provide powerful connections between microscopic theoretical predictions and experimental data, but requires complex electronic-structure formulations that fall outside the domain of applicability of common approaches, such as density-functional theory. We show here that Koopmans-compliant functionals, constructed to enforce piecewise linearity and the correct discontinuity derivative in energy functionals with respect to fractional occupation - i.e., with respect to charged excitations - provide molecular photoemission spectra and momentum maps of Dyson orbitals that are in excellent agreement with experimental ultraviolet photoemission spectroscopy and orbital tomography data. These results highlight the role of Koopmans-compliant functionals as accurate and inexpensive quasiparticle approximations to the spectral potential. © 2015 American Physical Society.

Bini D.,CNR Institute of Neuroscience | Damour T.,Institute des Hautes etudes Scientifiques
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

Continuing our analytic computation of the first-order self-force contribution to Detweiler's redshift variable we provide the exact expressions of the ninth and ninth-and-a-half post-Newtonian terms. © 2015 American Physical Society.

Bini D.,CNR Institute of Neuroscience | Damour T.,Institute des Hautes etudes Scientifiques
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

Continuing our analytic computation of the first-order self-force contribution to the "geodetic" spin precession frequency of a small spinning body orbiting a large (nonspinning) body, we provide the exact expressions of the 10 and 10.5 post-Newtonian terms. We also introduce a new approach to the analytic computation of self-force regularization parameters based on a WKB analysis of the radial and angular equations satisfied by the metric perturbations. © 2015 American Physical Society.

Patane G.,CNR Institute of Neuroscience
Computers and Graphics (Pergamon) | Year: 2015

This paper proposes an accurate and computationally efficient solver of the heat equation (t+Δ)F(·,t)=0, F(·,0)=f, on a volumetric domain, through the (r,r)-degree Padé-Chebyshev rational approximation of the exponential representation F(·,t)=exp(-tΔ)f of the solution. To this end, the heat diffusion problem is converted to a set of r differential equations, which involve only the Laplace-Beltrami operator, and whose solution converges to F(·,t), as r→+∞. The discrete heat equation is equivalent to r sparse, symmetric linear systems and is independent of the volume discretization as a tetrahedral mesh or a regular grid, the evaluation of the Laplacian spectrum, and the selection of a subset of eigenpairs. Our approach has a super-linear computational cost, is free of user-defined parameters, and has an approximation accuracy lower than 10-r. Finally, we propose a simple criterion to select the time value that provides the best compromise between approximation accuracy and smoothness of the solution. © 2014 Elsevier Ltd.

Chiorazzi N.,Feinstein Institute for Medical Research | Efremov D.G.,CNR Institute of Neuroscience
Cell Research | Year: 2013

The significant correlation between disease aggressiveness and the gene and protein structures of the B-cell receptors (BCRs) expressed on chronic lymphocytic leukemia (CLL) cells, together with the evidence for chronic activation of the BCR pathway, have led to the hypothesis that this leukemia initiates and progresses by selecting normal B lymphocytes reactive with a restricted set of (auto)antigens. A study recently published in Nature identified a novel signal-initiating interaction between the third complementary determining region of the IG heavy chain variable domain (HCDR3) and an epitope in the second framework region (FR2) that appears to be unique to CLL B cells and that calls into question the need for classical antigen binding in the activation and expansion of the leukemic cells. These findings are discussed in the context of available information about the antigen reactivity of CLL B cells and its potential role in clonal survival and drive. © 2013 IBCB, SIBS, CAS All rights reserved.

Pulcini G.,CNR Institute of Neuroscience
Reliability Engineering and System Safety | Year: 2016

This paper proposes a new perturbed gamma process, where the distribution of the measurement errors is assumed to be statistically dependent on the level (or state) of the hidden process. The main distributional characteristics of the proposed model, such as the marginal and conditional probability distributions of the level of the hidden process, of the measured level, and of the measurement errors, are then provided. Other quantities of large interest, such as the "failed" and "false" alarm probabilities and the reliability functions, are also provided. The maximum likelihood estimate of the model parameters is discussed, both when the inspections are not destructive and when they are invasive or destructive. In case the inspections are destructive and the standard deviation of the measurement error depends linearly on the actual process level, some distributional approximations are also suggested in order to facilitate the parameters estimation. Finally, two numerical applications are used to illustrate the feasibility of the proposed perturbed model in an applicative framework. © 2016 Elsevier Ltd. All rights reserved.

Rontani M.,CNR Institute of Neuroscience
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2013

A simple theory for the tunneling of two cold atoms out of a trap in the presence of an attractive contact force is developed. Two competing decay channels, for single-atom and bound-pair tunneling, respectively, contribute independently to the decay law of the mean atom number in the trap. The single-atom tunneling rate is obtained through the quasiparticle wave function formalism. For pair tunneling an effective equation for the center-of-mass motion is derived, so the calculation of the corresponding tunneling rate is again reduced to a simpler one-body problem. The predicted dependence of tunneling rates on the interaction strength qualitatively agrees with a recent measurement of the two-atom decay time. © 2013 American Physical Society.

Sulpizio S.,University of Trento | Spinelli G.,University of Rome La Sapienza | Burani C.,CNR Institute of Neuroscience | Burani C.,University of Trieste
Journal of Experimental Psychology: Human Perception and Performance | Year: 2015

Three experiments of pseudoword reading assessed whether stress assignment affects reading aloud at the level of articulation planning. In Experiment 1 (immediate reading) both stimulus length (in syllables) and stress type affected reading latency and accuracy. Italian pseudowords were named faster and more accurately when they were assigned stress on the antepenultimate rather than on the penultimate syllable. In Experiment 2 (delayed reading) reading aloud of the same stimuli was not affected by length but was still affected by stress type, with shorter latencies for pseudowords stressed on the antepenultimate syllable. Experiment 3 replicated the results of the first two experiments with new materials and with a tightly controlled procedure. These results indicate that stress assignment exerts an effect in a processing component where articulation is planned since articulation cannot start until stress is assigned. Our results also suggest that, in reading aloud, the minimal planning unit for articulation is smaller than the whole stimulus, including the first syllable up to the stressed unit. © 2015 American Psychological Association.

Fabiano E.,CNR Institute of Neuroscience | Constantin L.A.,Italian Institute of Technology
Physical Review A - Atomic, Molecular, and Optical Physics | Year: 2013

We discuss a β-dependent family of electronic density scalings of the form nλ(r)=λ3β+1n(λβr) in the context of density functional theory. In particular, we consider the following special cases: the Thomas-Fermi scaling (β=1/3 and λ1), which is crucial for the semiclassical theory of neutral atoms; the uniform-electron-gas scaling (β=-1/3 and λ1), that is important in the semiclassical theory of metallic clusters; the homogeneous density scaling (β=0) which can be related to the self-interaction problem in density functional theory when λ≤1; the fractional scaling (β=1 and λ≤1), that is important for atom and molecule fragmentation; and the strong-correlation scaling (β=-1 and λ1) that is important to describe the strong correlation limit. The results of our work provide evidence for the importance of this family of scalings in semiclassical and quantum theory of electronic systems, and indicate that these scaling properties must be considered as important constraints in the construction of new approximate density functionals. We also show, using the uniform-electron-gas scaling, that the curvature energy of metallic clusters is related to the second-order gradient expansion of kinetic and exchange-correlation energies. © 2013 American Physical Society.

Bini D.,CNR Institute of Neuroscience | Bini D.,University of Rome La Sapienza | Mashhoon B.,University of Missouri
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

We study Weitzenböck's torsion and discuss its properties. Specifically, we calculate the measured components of Weitzenböck's torsion tensor for a frame field adapted to static observers in a Fermi normal coordinate system that we establish along the world line of an arbitrary accelerated observer in general relativity. A similar calculation is carried out in the standard Schwarzschild-like coordinates for static observers in the exterior Kerr spacetime; we then compare our results with the corresponding curvature components. Our work supports the contention that in the extended general relativistic framework involving both the Levi-Civita and Weitzenböck connections, curvature and torsion provide complementary representations of the gravitational field. © 2015 American Physical Society.

Fabiano E.,CNR Institute of Neuroscience | della Sala F.,Italian Institute of Technology
Theoretical Chemistry Accounts | Year: 2012

We construct a reference benchmark set for atomic and molecular random phase approximation (RPA) correlation energies in a density functional theory framework at the complete basis-set limit. This set is used to evaluate the accuracy of some popular extrapolation schemes for RPA all-electron molecular calculations. The results indicate that for absolute energies, accurate results, clearly outperforming raw data, are achievable with twopoint extrapolation schemes based on quintuple- and sextuple- zeta basis sets. Moreover, we show that results in good agreement with the benchmark can also be obtained by using a semiempirical extrapolation procedure based on quadruple- and quintuple-zeta basis sets. Finally, we analyze the performance of different extrapolation schemes for atomization energies. © Spnger-Verlag 2012.

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.

Mejia-Rodriguez A.R.,CNR Institute of Neuroscience
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference | Year: 2011

This paper presents the evaluation of the accuracy of an elastic registration algorithm, based on the particle filter and an optical flow process. The algorithm is applied in brain CT and MRI simulated image datasets, and MRI images from a real clinical radiotherapy case. To validate registration accuracy, standard indices for registration accuracy assessment were calculated: the dice similarity coefficient (DICE), the average symmetric distance (ASD) and the maximal distance between pixels (Dmax). The results showed that this registration process has good accuracy, both qualitatively and quantitatively, suggesting that this method may be considered as a good new option for radiotherapy applications like patient's follow up treatment.

Costa G.,University of Cagliari | Morelli M.,University of Cagliari | Morelli M.,CNR Institute of Neuroscience | Simola N.,University of Cagliari
International Journal of Neuropsychopharmacology | Year: 2015

Background: Rats emit 50 kHz ultrasonic vocalizations (USVs) in response to either natural or pharmacological pleasurable stimuli, and these USVs have emerged as a new behavioral measure for investigating the motivational properties of drugs. Earlier studies have indicated that activation of the dopaminergic system is critically involved in 50 kHz USV emissions. However, evidence also exists that non-dopaminergic neurotransmitters participate in this behavioral response. Methods: To ascertain whether glutamate transmission plays a role in 50 kHz USV emissions stimulated by amphetamine, rats received five amphetamine (1-2 mg/kg, i.p.) administrations on alternate days in a test cage, either alone or combined with the glutamate N-methyl-D-aspartate receptor antagonist MK-801 (0.1-0.5 mg/kg, i.p.). Seven days after treatment discontinuation, rats were re-exposed to the test cage to assess drug conditioning, and afterwards received a drug challenge. USVs and locomotor activity were evaluated, along with immunofluorescence for Zif-268 in various brain regions and spontaneous alternation in a Y maze. Results: Amphetamine-treated rats displayed higher 50 kHz USV emissions and locomotor activity than vehicle-treated rats, and emitted conditioned vocalizations on test cage re-exposure. Rats co-administered amphetamine and MK-801 displayed lower and dose-dependent 50 kHz USV emissions, but not lower locomotor activity, during repeated treatment and challenge, and scarce conditioned vocalization compared with amphetamine-treated rats. These effects were associated with lower levels of Zif-268 after amphetamine challenge and spontaneous alternation deficits. Conclusions: These results indicate that glutamate transmission participates in the acute, long-term, and conditioned effects of amphetamine on 50 kHz USVs, possibly by influencing amphetamine-induced long-term neuronal changes and/or amphetamine-associated memories. © The Author 2015. Published by Oxford University Press on behalf of CINP.

Cozza G.,University of Padua | Pinna L.A.,University of Padua | Pinna L.A.,CNR Institute of Neuroscience | Moro S.,University of Padua
Current Medicinal Chemistry | Year: 2013

Protein kinase CK2 (Casein Kinase 2) is an essential, ubiquitous and highly pleiotropic protein kinase, implicated in several human diseases. In the last decade, several inhibitors of CK2, have been discovered and characterized to be ATP-competitive compounds. However, only one of them, CX-4945, has recently completed Phase I clinical trial as potential anticancer drug. In this review, we report all chemical classes of CK2 inhibitors available in literature, focusing our attention on conventional ATP-competitive and on non ATP-competitive inhibitors, which could represent a new frontier in CK2 inhibition and, consequently, a promising field of study in discovering new drug candidates. © 2013 Bentham Science Publishers.

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.

Ciuchi S.,CNR Institute of Neuroscience | Fratini S.,CNRS Neel Institute
Physical Review B - Condensed Matter and Materials Physics | Year: 2012

We explore the charge transport mechanism in organic semiconductors based on a model that accounts for the thermal intermolecular disorder at work in pure crystalline compounds, as well as extrinsic sources of disorder that are present in current experimental devices. Starting from the Kubo formula, we describe a theoretical framework that relates the time-dependent quantum dynamics of electrons to the frequency-dependent conductivity. The electron mobility is then calculated through a relaxation time approximation that accounts for quantum localization corrections beyond Boltzmann theory, and allows us to efficiently address the interplay between highly conducting states in the band range and localized states induced by disorder in the band tails. The emergence of a "transient localization" phenomenon is shown to be a general feature of organic semiconductors that is compatible with the bandlike temperature dependence of the mobility observed in pure compounds. Carrier trapping by extrinsic disorder causes a crossover to a thermally activated behavior at low temperature, which is progressively suppressed upon increasing the carrier concentration, as is commonly observed in organic field-effect transistors. Our results establish a direct connection between the localization of the electronic states and their conductive properties, formalizing phenomenological considerations that are commonly used in the literature. © 2012 American Physical Society.