pinecone/core-2020-05-10-deduplication huggingface dataset:
Probabilistic versus incremental presynaptic learning in biological plausible synapses

In this paper, the presynaptic rule, a classical rule for hebbian learning, is revisited. It is shown that the presynaptic rule exhibits relevant synaptic properties like synaptic directionality, and LTP metaplasticity (long-term potentiation threshold metaplasticity). With slight modifications, the presynaptic model also exhibits metaplasticity of the long-term depression threshold, being also consistent with Artola, Brocher and Singer’s (ABS) influential model. Two asymptotically equivalent versions of the presynaptic rule were adopted for this analysis: the first one uses an incremental equation while the second, conditional probabilities. Despite their simplicity, both types of presynaptic rules exhibit sophisticated biological properties, specially the probabilistic versio
A review of the potential of renewable energy sources for the State of Jammu and Kashmir (India)

The future economic development trajectory for India is likely to result in rapid and accelerated growth in energy demand, with expected shortages. Many of its current policies and strategies are aimed at the improvement and possible maximization of energy production from the renewable sector. It is also clear that while energy-conservation and energy-efficiency can make an important contribution in the national energy strategy, renewable energies will be essential to the solution and are likely to play an increasingly important role for the growth of grid power, providing energy access, reducing consumption of fossil fuels, and helping India pursue its low carbon progressive pathway. However, most of the states in India, like the northernmost State of Jammu and Kashmir (J&K), have experienced an energy crisis over a sustained period of time. As India intends to be one of the emerging powers of the 21st century, it has to embark upon with these pressing issues in a more sustainable manner and accordingly initiate various renewable energy projects within these states. This paper will provide a broad-spectrum view about the energy situation within J&K and will highlight the current policies along with future strategies for the optimal utilization of renewable energy resources
GreenDisc: a HW/SW energy optimization framework in globally distributed computation

In recent future, wireless sensor networks (WSNs) will experience a broad high-scale deployment (millions of nodes in the national area) with multiple information sources per node, and with very specific requirements for signal processing. In parallel, the broad range deployment of WSNs facilitates the definition and execution of ambitious studies, with a large input data set and high computational complexity. These computation resources, very often heterogeneous and driven on-demand, can only be satisfied by high-performance Data Centers (DCs). The high economical and environmental impact of the energy consumption in DCs requires aggressive energy optimization policies. These policies have been already detected but not successfully proposed. In this context, this paper shows the following on-going research lines and obtained results. In the field of WSNs: energy optimization in the processing nodes from different abstraction levels, including reconfigurable application specific architectures, efficient customization of the memory hierarchy, energy-aware management of the wireless interface, and design automation for signal processing applications. In the field of DCs: energy-optimal workload assignment policies in heterogeneous DCs, resource management policies with energy consciousness, and efficient cooling mechanisms that will cooperate in the minimization of the electricity bill of the DCs that process the data provided by the WSNs
Optical in situ monitoring of hydrogen desorption from Ge(100) surfaces

Molecular hydrogen strongly interacts with vicinal Ge(100) surfaces during preparation in a metal organic vapor phase epitaxy reactor. According to X-ray photoemission spectroscopy and Fourier-transform infrared spectroscopy results, we identify two characteristic reflection anisotropy (RA) spectra for H-free and monohydride-terminated vicinal Ge(100) surfaces. RAS allows in situ monitoring of the surface termination and enables spectroscopic hydrogen kinetic desorption studies on the Ge(100) surface. Comparison of evaluated values for the activation energy and the pre-exponential factor of H desorption evaluated at different photon energies reflects that H unevenly affects the shape of the RA spectrum
Molecular dynamics modeling and simulation of void growth in two dimensions

The mechanisms of growth of a circular void by plastic deformation were studied by means of molecular dynamics in two dimensions (2D). While previous molecular dynamics (MD) simulations in three dimensions (3D) have been limited to small voids (up to ≈10 nm in radius), this strategy allows us to study the behavior of voids of up to 100 nm in radius. MD simulations showed that plastic deformation was triggered by the nucleation of dislocations at the atomic steps of the void surface in the whole range of void sizes studied. The yield stress, defined as stress necessary to nucleate stable dislocations, decreased with temperature, but the void growth rate was not very sensitive to this parameter. Simulations under uniaxial tension, uniaxial deformation and biaxial deformation showed that the void growth rate increased very rapidly with multiaxiality but it did not depend on the initial void radius. These results were compared with previous 3D MD and 2D dislocation dynamics simulations to establish a map of mechanisms and size effects for plastic void growth in crystalline solids
A comparative analysis between FEM and Boundary Methods in bending of Plates

Two different methods of analysis of plate bending, FEM and BM are discussed in this paper. The plate behaviour is assumed to be represented by using the linear thin plate theory where the Poisson-Kirchoff assumption holds. The BM based in a weighted mean square error technique produced good results for the problem of plate bending. The computational effort demanded in the BM is smaller than the one needed in a FEM analysis for the same level of accuracy. The general application of the FEM cannot be matched by the BM. Particularly, different types of geometry (plates of arbitrary geometry) need a similar but not identical treatment in the BM. However, this loss of generality is counterbalanced by the computational efficiency gained in the BM in the solution achievemen
Insights into the production and characterization of electrospun fibers from regenerated silk fibroin

Regenerated silk fibroin solutions from Bombyx mori were tested for electrospinning.Simple and reproducible tensile tests were performed on threads of aligned fibers to obtain information about their mechanical performance at the fiber level. The binary solvent formic acid/chloroform (10:1, v/v) rendered unbeaded thinner fibers with increased extensibility before failure when compared with pure formic acid. A remarkable improvement in strength was induced by immersing length-restricted fibers into ethanol for 5 min. Conformational changes of the protein chains were studied by solid-state NMR
Implications of low breakdown voltage of component subcells on external quantum efficiency measurements of multijunction solar cells

The electrical and optical coupling between subcells in a multijunction solar cell affects its external quantum efficiency (EQE) measurement. In this study, we show how a low breakdown voltage of a component subcell impacts the EQE determination of a multijunction solar cell and demands the use of a finely adjusted external voltage bias. The optimum voltage bias for the EQE measurement of a Ge subcell in two different GaInP/GaInAs/Ge triple-junction solar cells is determined both by sweeping the external voltage bias and by tracing the I–V curve under the same light bias conditions applied during the EQE measurement. It is shown that the I–V curve gives rapid and valuable information about the adequate light and voltage bias needed, and also helps to detect problems associated with non-ideal I–V curves that might affect the EQE measurement. The results also show that, if a non-optimum voltage bias is applied, a measurement artifact can result. Only when the problems associated with a non-ideal I–V curve and/or a low breakdown voltage have been discarded, the measurement artifacts, if any, can be attributed to other effects such as luminescent coupling between subcells
Big data for microstructure-property relationships : a case study of predicting effective conductivities

The analysis of big data is changing industries, businesses and research as large amounts of data are available nowadays. In the area of microstructures, acquisition of (3-D tomographic image) data is difficult and time-consuming. It is shown that large amounts of data representing the geometry of virtual, but realistic 3-D microstructures can be generated using stochastic microstructure modeling. Combining the model output with physical simulations and data mining techniques, microstructure-property relationships can be quantitatively characterized. Exemplarily, we aim to predict effective conductivities given the microstructure characteristics volume fraction, mean geodesic tortuosity, and constrictivity. Therefore, we analyze 8119 microstructures generated by two different stochastic 3-D microstructure models. This is — to the best of our knowledge — by far the largest set of microstructures that has ever been analyzed. Fitting artificial neural networks, random forests and classical equations, the prediction of effective conductivities based on geometric microstructure characteristics is possible
Development of a mechanism and an accurate and simple mathematical model for the description of drug release: Application to a relevant example of acetazolamide-controlled release from a bio-inspired elastin-based hydrogel

Producción CientíficaTransversality between mathematical modeling, pharmacology, and materials science is essential in order to achieve controlled-release systems with advanced properties. In this regard, the area of biomaterials provides a platform for the development of depots that are able to achieve controlled release of a drug, whereas pharmacology strives to find new therapeutic molecules and mathematical models have a connecting function, providing a rational understanding by modeling the parameters that influence the release observed. Herein we present a mechanism which, based on reasonable assumptions, explains the experimental data obtained very well. In addition, we have developed a simple and accurate “lumped” kinetics model to correctly fit the experimentally observed drug release behavior. This lumped model allows us to have simple analytic solutions for the mass and rate of drug release as a function of time without limitations of time or mass of drug released, which represents an important step-forward in the area of in vitro drug delivery when compared to the current state of the art in mathematical modeling. As an example, we applied the mechanism and model to the release data for acetazolamide from a recombinant polymer. Both materials were selected because of a need to develop a suitable ophthalmic formulation for the treatment of glaucoma. The in vitro release model proposed herein provides a valuable predictive tool for ensuring product performance and batch-to-batch reproducibility, thus paving the way for the development of further pharmaceutical devices.Este trabajo forma parte de los Proyectos de Investigación financiados por la Comisión Europea a través del Fondo Social Europeo (FSE) y de la Consejería de Educación mediante el Fondo Europeo de Desarrollo Regional (ERDF), el MINECO (Proyectos MAT2013-41723-R, MAT2013-42473-R, PRI−PIBAR-2011-1403 y MAT2012-38043), la Junta de Castilla y León (Proyectos VA155A12, VA152A12, and VA244U13), el CIBER-BBN y el Instituto de Salud Carlos III mediante el Centro de Medicina Regenerativa y Terapia Celular de Castilla y León
Understanding the quality of life of family carers of people with dementia: development of a new conceptual framework

Background\ud
Dementia is a major global health and social care challenge, and family carers are a vital determinant of positive outcomes for people with dementia. This study's aim was to develop a conceptual framework for the Quality of Life (QOL) of family carers of people with dementia.\ud
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Methods\ud
We studied family carers of people with dementia and staff working in dementia services iteratively using in‐depth individual qualitative interviews and focus groups discussions. Analysis used constant comparison techniques underpinned by a collaborative approach with a study‐specific advisory group of family carers.\ud
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Results\ud
We completed 41 individual interviews with 32 family carers and nine staff and two focus groups with six family carers and five staff. From the analysis, we identified 12 themes that influenced carer QOL. These were organised into three categories focussing on person with dementia, carer, and external environment.\ud
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Conclusions\ud
For carers of people with dementia, the QOL construct was found to include condition‐specific domains which are not routinely considered in generic assessment of QOL. This has implications for researchers, policy makers, and service providers in addressing and measuring QOL in family carers of people with dementia
Single electron transfer-degenerative chain transfer living radical polymerization of N-butyl acrylate catalyzed by Na2S2O4 in water media

Living radical polymerization of n-butyl acrylate was achieved by single electron transfer/degenerative-chain transfer mediated living radical polymerization in water catalyzed by sodium dithionate. The plots of number-average molecular weight versus conversion and ln[M]0/[M] versus time are linear, indicating a controlled polymerization. This methodology leads to the preparation of alpha,omega-di(iodo) poly (butyl acrylate) (alpha,omega-di(iodo)PBA) macroinitiators. The influence of polymerization degree ([monomer]/[initiator]), amount of catalyst, concentration of suspending agents and temperature were studied. The molecular weight distributions were determined using a combination of three detectors (TriSEC): right-angle light scattering (RALLS), a differential viscometer (DV), and refractive index (RI). The methodology studied in this work represents a possible route to prepare well-tailored macromolecules made of butyl acrylate in an environmental friendly reaction medium. Moreover, such materials can be subsequently functionalized leading to the formation of different block copolymers of composition ABA. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2809-2825, 2006http://dx.doi.org/10.1002/pola.2138
Spectral and electrochemical studies on blends of polyaniline and cellulose esters

Blends of chemically prepared polyaniline emeraldine base (PANi) with cellulose esters were studied as films by UV-visible spectroscopy and cyclic voltammetry. The cellulose esters used were acetate, propionate, acetate butyrate, and acetate hydrogen phthalate. Films were prepared by casting from N-methylpyrrolidone or formic acid, and the effect of doping by acids on their spectral and electrochemical properties was studied. Similar behavior was observed with the acetate, propionate, or acetate butyrate, with spectral changes on adding acid due to protonation of the PANi. In agreement with previous studies, kinetic measurements on PANi in a cellulose acetate matrix shows a relatively slow spectral change on protonation. In contrast, with cellulose acetate hydrogen phthalate (CAHP), no changes were observed on adding acid, and it is suggested that the hydrogen phthalate group acts as proton donor. This was mirrored by the cyclic voltammetry behavior in hydrochloric acid solution. Electrochemical studies on films of PANi/CAHP blends in different relative proportions in sulfuric acid solution show a marked dependence on the solvent used for casting, with higher currents and better electrical conductivity being observed in films prepared from N-methylpyrrolidone. This is shown to be due to the presence of PANi particles in the films. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2182-2188, 2002http://dx.doi.org/10.1002/app.1116
Electrochemical Behavior of Thalidomide at a Glassy Carbon Electrode

Thalidomide is an oral drug marketed in the 1950s as a sedative and an anti-emetic during pregnancy that was removed from the market when its teratogenic side effects appeared in new born children due to inadequate tests to assess the drug's safety. Recent studies evaluating the use of thalidomide in cancer and HIV diseases have sparked renewed interest. The electrochemical behavior of thalidomide on a glassy carbon electrode has been investigated using cyclic, differential and square-wave voltammetry in aqueous media at different pHs. The oxidation mechanism of thalidomide is an irreversible, adsorption-controlled process, pH dependent up to values close to the pKa and occurs in two consecutive charge transfer reactions. A mechanism of oxidation of thalidomide involving one electron and one proton to produce a cation radical, which reacts with water and yields a final hydroxylated product is proposed. The reduction of thalidomide is also a pH dependent, irreversible process and occurs in a single step, with the same number of electrons and protons transferred. The reduction mechanism involves the protonation of the nitrogen that bridges the two cyclic groups, and the product of the protonation reaction causes irreversible dissociation. Both thalidomide and the non electroactive oxidation and reduction products are strongly adsorbed on the glassy carbon electrode surface.http://dx.doi.org/10.1002/elan.20080434
Influence of the sample preparation method on the serotonin determination in plasma and platelets

Plasma or platelet serotonin concentration is commonly used to provide information about the serotonergic activity in various psychiatric or neurological diseases. Some difficulties have been described in the measurement of serotonin (5-HT) levels in plasma or platelets. We describe an isocratic liquid-chromatographic assay with amperometric detection for determination of 5-HT in the platelet pellet and in platelet-rich and platelet-poor plasma (PRP and PPP) in sample sizes of 100 µL of plasma. The method uses an RP18 column and an amperometric detector with a thin-layer type electrochemical flow cell, with glassy carbon electrode maintained at a potential of +0.600 V vs an Ag/AgCl reference electrode. Determinations were performed in the presence or in the absence of plasma, since the biological matrix may affect the results. Different validation parameters were analysed: selectivity, accuracy, precision, linearity and stability. Reference values for 5-HT concentration in healthy adults (n = 12) were 6.6 nmol/109 platelets, for the platelet pellet, and 5.5 nmol/109 platelets, for PRP. The 100 µL sample volume used for the preparation of PPP did not make possible the determination of 5-HT levels with accuracy and precision. Copyright © 2004 John Wiley & Sons, Ltd.http://dx.doi.org/10.1002/bmc.38
Levels, sources and seasonality of coarse particles (PM10-PM2.5) in three European capitals e implications for particulate pollution control

Coarse particles of aerodynamic diameter between 2.5 and 10 mm (PMc) are produced by a range of natural (windblown dust and sea sprays) and anthropogenic processes (non-exhaust vehicle emissions, industrial, agriculture, construction and quarrying activities). Although current ambient air quality regulations focus on PM2.5 and PM10, coarse particles are of interest from a public health point of view as they have been associated with certain mortality and morbidity outcomes.  In this paper, an analysis of coarse particle levels in three European capitals (London, Madrid and Athens) is presented and discussed. For all three cities we analysed data from both traffic and urban background monitoring sites. The results showed that the levels of coarse particles present significant seasonal, weekly and daily variability. Their wind driven and non-wind driven resuspension as well as their roadside increment due to traffic were estimated. Both the local meteorological conditions and the air mass history indicating long-range atmospheric transport of particles of natural origin are significant parameters that influence the levels of coarse particles in the three cities especially during episodic events
Defect-mediated ferromagnetism in ZnO:Mn nanorods

In this work, the structural, chemical and magnetic properties of ZnO:Mn nanorods were investigated. Firstly, well-aligned ZnO nanorods with their long axis parallel to the crystalline c-axis were successfully grown by the vapor phase transport technique on Si substrates coated with a ZnO buffer layer. Mn metal was then diffused into these nanorods at different temperatures in vacuum. From SEM results, ZnO:Mn nanorods were observed to have diameters of ~100 nm and lengths of 4 µm. XPS analysis showed that the Mn dopant substituted into the ZnO matrix with a valence state of +2. Magnetic measurements performed at room temperature revealed that undoped ZnO nanorods exhibit ferromagnetic behavior which may be related to oxygen vacancy defect-mediated d0 ferromagnetism. ZnO:Mn samples were seen to show an excess room temperature ferromagnetism that is attributed to the presence of oxygen vacancy defects forming bound magnetic polarons involving Mn
The Spectra of heterotic standard model vacua

A formalism for determining the massless spectrum of a class of realistic heterotic string vacua is presented. These vacua, which consist of SU(5) holomorphic bundles on torus-fibered Calabi-Yau threefolds with fundamental group Z_2, lead to low energy theories with standard model gauge group (SU(3)_C x SU(2)_L x U(1)_Y)/Z_6 and three families of quarks and leptons. A methodology for determining the sheaf cohomology of these bundles and the representation of Z_2 on each cohomology group is given. Combining these results with the action of a Z_2 Wilson line, we compute, tabulate and discuss the massless spectrum
Simulation of Polymer Flow Using Smoothed Particle Hydrodynamics Method

Reactive rotational molding (RRM) is a process to manufacture hollow plastic articles. Comparing to rotational molding of thermoplastics, it decreases the process cycle time due to the reactivity of the system. However, the number of influent parameters is relatively high and optimization of the process is complex. During RRM, the viscosity is one of the key parameters and varies according to the polymer molecular weight due to chemical reactions. Simulation is a way to optimize this process. Prediction of the reactive flow is of great interest to optimize process conditions and wall thickness distribution of the molded part. We developed a solver based on smoothed particle hydrodynamics method. This Lagrangian meshfree method is well adapted to simulate free surface flows like those occurring in RRM. First, we validated the code comparing the simulation results to analytical Couette flow solution and experimental  measurements of dam break problem. Then, we performed two-dimensional (2D) and 3D simulations to observe the influence of the change of viscosity on the flow, due to the chemical reactions. Adhesion of the polymer on the mold surface is modeled by new boundary conditions.Contract grant sponsor : RAIGI society for providing us the reactive materials and the Single Interministerial Fund (FUI)-SAGANE