pinecone/core-2020-05-10-deduplication huggingface dataset:
High quality interconnected core/shell ZnO nanorod architectures grown by pulsed laser deposition on ZnO-seeded Si substrates

We report the production of vertically aligned and interconnected ZnO core/shell nanorods using pulsed laser deposition (PLD) in a continuous two-step growth process. X-ray diffraction studies showed wurtzite structure and c-axis orientation with a high degree of verticality. Scanning electron microscopy showed a characteristic interconnection morphology between the nanorod tips uniformly present over the entire sample surface area, while transmission electron microscopy revealed crystalline core/amorphous shell architecture. Strong bands at 98.7 cm-1 and 437.2 cm-1 (wurtzite ZnO low and high nonpolar E2 modes) were the main features of the nanorod Raman spectra, again showing the high sample quality. Low-temperature PL data exhibited strong I6 emission and structured green band showing high optical quality. Electrical studies indicated n-type material with ohmic behaviour. The results are discussed in the context of the advantages offered by interconnected architectures of core/shell ZnO nanostructures for various applications
Approximating the minimum hub cover problem on planar graphs

We study an approximation algorithm with a performance guarantee to solve a new NP-hard optimization problem on planar graphs. The problem, which is referred to as the minimum hub cover problem, has recently been introduced to the literature to improve query processing over large graph databases. Planar graphs also arise in various graph query processing applications, such as; biometric identification, image classification, object recognition, and so on. Our algorithm is based on a well-known graph decomposition technique that partitions the graph into a set of outerplanar graphs and provides an approximate solution with a proven performance ratio. We conduct a comprehensive computational experiment to investigate the empirical performance of the algorithm. Computational results demonstrate that the empirical  performance of the algorithm surpasses its guaranteed performance. We also apply the same decomposition approach to develop a decomposition-based heuristic, which is much more efficient than the approximation algorithm in terms of computation time. Computational results also indicate that the efficacy of the decomposition-based heuristic in terms of solution quality is comparable to that of the approximation algorithm
Evolution of optimal Hill coefficients in nonlinear public goods games

In evolutionary game theory, the effect of public goods like diffusible molecules has been\ud
modelled using linear, concave, sigmoid and step functions. The observation that biological\ud
systems are often sigmoid input-output functions, as described by the Hill equation, suggests that\ud
a sigmoid function is more realistic. The Michaelis-Menten model of enzyme kinetics, however,\ud
predicts a concave function, and while mechanistic explanations of sigmoid kinetics exist, we lack\ud
an adaptive explanation: what is the evolutionary advantage of a sigmoid benefit function? We\ud
analyse public goods games in which the shape of the benefit function can evolve, in order to\ud
determine the optimal and evolutionarily stable Hill coefficients. We find that, while the\ud
dynamics depends on whether output is controlled at the level of the individual or the\ud
population, intermediate or high Hill coefficients often evolve, leading to sigmoid input-output\ud
functions that for some parameters are so steep to resemble a step function (an on-off switch).\ud
Our results suggest that, even when the shape of the benefit function is unknown, models of\ud
biological public goods should be modelled using a sigmoid or step function rather than a linear\ud
or concave function
FRET-Paired Hydrogel Forming Silk-Elastin-Like Recombinamers by Recombinant Conjugation of Fluorescent Proteins

Producción CientíficaIn the last decades, recombinant structural proteins have become very promising in addressing different issues such as the lack of traceability of biomedical devices or the design of more sensitive biosensors. Among them, we find elastin-like recombinamers (ELRs), which can be designed to self-assemble into diverse structures, such as hydrogels. Furthermore, they might be combined with other protein polymers, such as silk, to give silk-elastin-like recombinamers (SELRs), holding the properties of both proteins. In this work, due to their recombinant nature, we have fused two different fluorescent proteins (FPs), i.e., the green Aequorea coerulescens enhanced green fluorescent protein and the near-infrared eqFP650, to a SELR able to form irreversible hydrogels through physical cross-linking. These recombinamers showed an emission of fluorescence similar to the single FPs, and they were capable of forming hydrogels with different stiffness (G′ = 60–4000 Pa) by varying the concentration of the SELR-FPs. Moreover, the absorption spectrum of SELR-eqFP650 showed a peak greatly overlapping the emission spectrum of the SELR-Aequorea coerulescens enhanced green fluorescent protein. Hence, this enables Förster resonance energy transfer (FRET) upon the interaction between two SELR molecules, each one containing a different FP, due to the stacking of silk domains at any temperature and to the aggregation of elastin-like blocks above the transition temperature. This effect was studied by different methods, and a FRET efficiency of 0.06–0.2 was observed, depending on the technique used for its calculation. Therefore, innovative biological applications arise from the combination of SELRs with FPs, such as enhancing the traceability of hydrogels based on SELRs intended for tissue engineering, the development of biosensors, and the prediction of FRET efficiencies of novel FRET pairs.Este trabajo forma parte de Proyectos de Investigación financiados por la Comisión Europea (NMP-2014-646075, HEALTH-F4-2011-278557, PITN-GA-2012-317306 and MSCA-ITN-2014-642687), del MINECO  (MAT2016-7R8903-R, MAT2016-79435-R, MAT2013-42473-R, MAT2013-41723- and MAT2012-38043), la Junta de Castilla y León (VA244U13 and VA313U14)  y el Centro en Red de Medicina Regenerativa y Terapia Celular de Castilla y León
Increases in kidney volume in autosomal dominant polycystic kidney disease can be detected within 6 months

Kidney volume growth is considered the best surrogate marker predicting the decline of renal function in autosomal dominant polycystic kidney disease. To assess the therapeutic benefit of new drugs more rapidly, changes in kidney volume need to be determined over a short time interval. Here we measured renal volume changes by manual segmentation volumetry applied to magnetic resonance imaging scans obtained with an optimized T1-weighted acquisition protocol without gadolinium-based contrast agents. One hundred young patients with autosomal dominant polycystic kidney disease and preserved renal function had a significant increase in total kidney volume by 2.71±4.82% in 6 months. Volume measurements were highly reproducible and accurate, as indicated by correlation coefficients of 1.000 for intra-observer and 0.996 for inter-observer agreement, with acceptable within-subject standard deviations. The change in renal volume correlated with baseline total kidney volume in all age subgroups. Total kidney volume positively correlated with male gender, hypertension, albuminuria and a history of macrohematuria but negatively with creatinine clearance. Albuminuria was associated with accelerated volume progression. Our study shows that increases in kidney volume can be reliably measured over a 6 month period in early autosomal dominant polycystic kidney disease using unenhanced magnetic resonance imaging sequences
An efficient implementation of the synchronization likelihood algorithm for functional connectivity

Measures of functional connectivity are commonly employed in neuroimaging research. Among the most popular measures is the Synchronization Likelihood which provides a non-linear estimate of the statistical dependencies between the activity time courses of different brain areas. One aspect which has limited a wider use of this algorithm is the fact that it is very computationally and memory demanding. In the present work we propose new implementations and parallelizations of the Synchronization Likelihood algorithm with significantly better performance both in time and in memory use. As a result both the amount of required computational time is reduced by 3 orders of magnitude and the amount of memory needed for calculations is reduced by 2 orders of magnitude. This allows performing analyses that were not feasible before from a computational standpoint
Do charismatic species groups generate more cultural ecosystem service benefits?

The relationship between nature and cultural ecosystem service (CES) benefits is well accepted but poorly understood, as is the potential role of biodiversity in the relationship. By means of a public questionnaire survey in Wiltshire, UK, the relationship between the presence of a range of common species groups, species group ‘charisma’, group abundance in the landscape, and the benefit that people felt that they derived from the species groups was investigated for a lowland multifunctional landscape.

Findings showed that species group charisma influenced the benefit reported by respondents for current abundance levels, and influenced their response to potential increases or decreases in abundance. Respondents reported high levels of benefit from species groups hypothesised to be charismatic (birds, flowering plants, butterflies) and there was high consistency in the pattern of response. Respondents reported less benefit from groups hypothesised to be less charismatic (beetles/bugs, brambles and nettles), the latter response patterns showing much greater variation. These results could be used to promote a more holistic understanding of the value of biodiversity by educating and informing the public so that they derive benefit not just from the charismatic, but also from the everyday, the commonplace and less obviously charismatic species
Psychological wellbeing and the diathesis-stress hypothesis model: the role of psychological functioning and quality of relations in promoting subjective well-being in a life events study

Negative life events are associated with poor wellbeing and mental health outcomes. Following a diathesis-stress model, we tested whether psychological functioning and quality of interpersonal relationships moderated the effect of life events on subjective wellbeing. This study comprised data from a young and middle-aged adult sample (n = 364) drawn from an Australian university-student population. Results indicated that life events were associated with negative but not positive wellbeing outcomes. Perceived impact of life events was a stronger predictor of wellbeing than was the number of life events. Psychological functioning and quality of interpersonal relationships were associated with both wellbeing dimensions but only quality of interpersonal relationships moderated the effect of life events on wellbeing. In conclusion, perceived impact of life events was more strongly related to wellbeing than number of life events. Interpersonal relationships moderate the effect of life events with those reporting higher levels of quality of interpersonal relationships reporting less decrement in negative affect following stressful life events.
Dead-end filtration of yeast suspensions: correlating specific resistance and flux data using artificial neural networks

The specific cake resistance in dead-end filtration is a complex function of suspension properties and operating conditions. In this study, the specific resistance of resuspended dried bakers yeast suspensions was measured in a series of 150 experiments covering a range of pressures, cell concentrations, pHs, ionic strengths and membrane resistances. The specific resistance was found to increase linearly with pressure and exhibited a complex dependence on pH and ionic strength. The specific resistance data were correlated using an artificial neural network containing a single hidden layer with nine neurons employing the sigmoidal activation function. The network was trained with 104 training points, 13 validation points and 33 test points. Excellent agreement was obtained between the neural network and the test data with average errors of less than 10%. In addition, a network was trained for prediction of the filtrate flux directly from the system inputs and this approach is easily extended to crossflow filtration by adding inputs such as the crossflow velocity and channel height. An attempt was made to interpret the network weights for both the specific resistance and flux networks. The effective contribution of each input to the system output was computed in each case and showed trends that were as expected. Although network weights, and consequently the computed effect of each parameter, is different each time a network is changed (depending on the initial weights used in the training process), the variation was low enough for information contained in the network to be interpreted in a meaningful way
Effects of n-butanol and filipin on membrane permeability of developing wheat endosperm with different sterol phenotypes.

Sterols are considered structural components of higher plant membranes on the basis of their presence in membrane-containing subcellular fractions [1—3], their effect on plant membrane permeability when added exogenously [4,5] and the sensitivity of plant cells to the polyene antibiotic filipin [6—8], which action is known to depend on the presence of sterols in the membrane (see [8]). Our recent finding of a gene that controls the free sterol level of developing wheat endosperm [9—11 ] allows to investígate whether endogenous sterol modifies membrane permeability in the same way as that added externally. We report here on the effect of «-butanol and filipin on the leakage properties of developing wheat endosperms with different genetically determined free sterol levéis
Bending continuous structures with SMAs: a novel robotic fish design

In this paper, we describe our research on bio-inspired locomotion systems using deformable structures and smart materials, concretely shape memory alloys (SMAs). These types of materials allow us to explore the possibility of building motor-less and gear-less robots.\ud
A swimming underwater fish-like robot has been developed whose movements are generated using SMAs. These actuators are suitable for bending the continuous backbone of the fish, which in turn causes a change in the curvature of the body. This type of structural arrangement is inspired by fish red muscles, which are mainly recruited during steady swimming for the bending of a flexible but nearly incompressible structure such as the fishbone. This paper\ud
reviews the design process of these bio-inspired structures, from the motivations and physiological inspiration to the mechatronics design, control and simulations, leading to actual experimental trials and results. The focus of this work is to present the mechanisms by which standard swimming patterns can be reproduced with the proposed design. Moreover, the performance of the SMA-based actuators’ control in terms of actuation speed and position accuracy is also addressed
Analysis of genetic variability in a sample of the durum wheat (Triticum durum Desf.) Spanish collection based on gliadin markers

In this work gliadin proteins were used to analyse the genetic variability in a sample of the durum wheat Spanish collection conserved at the CRF-INIA. In total 38 different alleles were identified at the loci Gli-A1, Gli-A3, Gli-B5, Gli-B1, Gli-A2 and Gli-B2. All the gliadin loci were polymorphic, possessed large genetic diversity and small and large differentiation within and between varieties, respectively. The Gli-A2 and Gli-B2 loci were the most polymorphic, the most fixed within varieties and the most useful to distinguish among varieties. Alternatively, Gli-B1 locus presented the least genetic variability out of the four main loci Gli-A1, Gli-B1, Gli-A2 and Gli-B2. The Gli-B1 alleles coding for the gliadin γ-45, associated with good quality, had an accumulated frequency of 69.7%, showing that the Spanish germplasm could be a good source for breeding quality. The Spanish landraces studied showed new gliadin alleles not catalogued so far. These new alleles might be associated with specific Spanish environment factors. The large number of new alleles identified also indicates that durum wheat Spanish germplasm is rather unique
Silicon Photomultipliers (SiPM) as novel photodetectors for PET

Next generation PET scanners should fulfill very high requirements in terms of spatial, energy and timing resolution. Modern scanner performances are inherently limited by the use of standard photomultiplier tubes. The use of Silicon Photomultipliers (SiPMs) is proposed for the construction of a 4D-PET module of 4.8×4.8 cm2 aimed to replace the standard PMT based PET block detector. The module will be based on a LYSO continuous crystal read on two faces by Silicon Photomultipliers. A high granularity detection surface made by SiPM matrices of 1.5 mm pitch will be used for the x–y photon hit position determination with submillimetric accuracy, while a low granularity surface constituted by 16 mm2 SiPM pixels will provide the fast timing information (t) that will be used to implement the Time of Flight technique (TOF). The spatial information collected by the two detector layers will be combined in order to measure the Depth of Interaction (DOI) of each event (z). The use of large area multi-pixel Silicon Photomultiplier (SiPM) detectors requires the development of a multichannel Data Acquisition system (DAQ) as well as of a dedicated front-end in order not to degrade the intrinsic detector capabilities and to manage many channels. The paper describes the progress made on the development of the proof of principle module under construction at the University of Pisa
Advances in the analysis of short span railway bridges for high-speed lines

The physical model based on moving constant loads is widely used for the analysis of railway bridges. Nevertheless, the moving loads model is not well suited for the study of short bridges (L⩽20–25 m) since the results it produces (displacements and accelerations) are much greater than those obtained from more sophisticated ones. In this paper two factors are analysed which are believed to have an influence in the dynamic behaviour of short bridges. These two factors are not accounted for by the moving loads model and are the following: the distribution of the loads due to the presence of the sleepers and ballast layer, and the train–bridge interaction. In order to decide on their influence several numerical simulations have been performed. The results are presented and discussed herein
Stock volatility in the periods of booms and stagnations

The aim of this paper is to compare statistical properties of stock price indices in periods of booms with those in periods of stagnations. We use the daily data of the four stock price indices in the major stock markets in the world: (i) the Nikkei 225 index (Nikkei 225) from January 4,
1975 to August 18, 2004, of (ii) the Dow Jones Industrial Average (DJIA) from January 2, 1946 to August 18, 2004, of (iii) Standard and Poor’s 500 index (SP500) from November 22, 1982 to August 18, 2004, and of (iii) the Financial Times Stock Exchange 100 index (FT 100) from April 2, 1984 to August 18, 2004. We divide the time series of each of these indices in the two periods: booms and stagnations, and investigate the statistical properties of absolute log return, which is a typical measure of volatility, for each period. We find that (i) the tail of the distribution of the absolute log-returns is approximated by a power-law function with the exponent close to 3 in the periods of booms while the distribution is described by an exponential
function with the scale parameter close to unity in the periods of stagnations.
A new stress sensor and risk factor for suicide: the T allele of the functional genetic variant in the GABRA6 gene

Low GABA transmission has been reported in suicide, and GABRA6 rs3219151 T allele has been associated with greater physiological and endocrine stress response in previous studies. Although environmental stress also plays a role in suicide, the possible role of this allele has not been investigated in this respect. In our present study effect of rs3219151 of GABRA6 gene in interaction with recent negative life events on lifetime and current depression, current anxiety, as well as lifetime suicide were investigated using regression models in a white European general sample of 2283 subjects. Post hoc measures for phenotypes related to suicide risk were also tested for association with rs3219151 in interaction with environmental stress. No main effect of the GABRA6 rs3219151 was detected, but in those exposed to recent negative life events GABRA6 T allele increased current anxiety and depression as well as specific elements of suicide risk including suicidal and death-related thoughts, hopelessness, restlessness and agitation, insomnia and impulsiveness as measured by the STOP task. Our data indicate that stress-associated suicide risk is elevated in carriers of the GABRA6 rs3219151 T allele with several independent markers and predictors of suicidal behaviours converging to this increased risk
Design of modiﬁed plastic surfaces for antimicrobial applications: Impact of ionizing radiation on the physical and mechanical properties of polypropylene

Surface modiﬁcation of polypropylene (PP) sheets was carried out by radiation induced graft polymer- ization of hydrophilic functional molecules such as N,N-dimethylacrylamide (DMA) and [2-methacry- loyloxy)ethyl] trimethylammonium chloride, which is a quaternary ammonium salt (QAS). Polypropylene sheets were activated prior to the grafting reaction by using electron beam radiation. The changes in morphology, crystallinity and tensile parameters like deformation and stress at yield and deformation at break of PP after irradiation were investigated. The results showed that a minor crystalline reorganization takes place during the irradiation of PP at 100 kGy. The grafting has been observed to be strongly dependent on the monomer dilution in the reaction medium. After grafting of QAS (40%) and DMA (20%) it was possible to develop highly hydrophilic surfaces (water contact angle comprised between 30 and 411). The surfaces of virgin, irradiated and grafted PP were studied using polarized optical microscopy (POM) and scanning electron microscopy (SEM). Spherical particles (i.e. polystyrene or silica beads) adhering to the modiﬁed samples were studied according to the surface parameters. Adhesion tests conﬁrmed the strong inﬂuence of substrate type (mainly  hydrophilicity  and  roughness)  and  to  a  lesser  extent  underlined  the  role  of  electrostatic interactions for the design of plastic surfaces for antimicrobial applications