pinecone/core-2020-05-10-deduplication huggingface dataset:
Chemical identification of luminescence due to Sn and Sb in ZnO

We show that the I10 line in ZnO photoluminescence is associated with Sn impurities. The evidence comes from material implanted with radioactive 117Ag, which decays through 117Cd and 117In to stable 117Sn, and 121Ag which decays through the same chain to stable 121Sb. Supporting evidence is provided by ZnO:Sn prepared by the in-diffusion of stable Sn. The I2 and I9 lines are also shown conclusively to be due to In, confirming earlier identifications in the literature. We also observe shallow bound exciton emission at 3.3643(3) eV due to Sb impurities produced at the end of the decay chain of 121Ag
Two-region model for positive and negative plasma sheaths and its application to Hall thruster metallic anodes.

An asymptotic presheath/sheath model for positive and negative sheaths in front of a conducting electrode, with a continuous parametric transition at the no-sheath case, is presented. Key aspects of the model are as follows: full hydrodynamics of both species in the presheath; a kinetic formulation with a truncated distribution function for the repelled species within the sheath; and the fulfillment of the marginal Bohm condition at the sheath edge, in order to match the two formulations of the repelled species. The sheath regime depends on the ratios of particle fluxes and sound speeds between the two species. The presheath model includes the effect of a magnetic field parallel to the wall on electrons. An asymptotic, parametric study of the anode presheath is carried out in terms of the local ion-to-electron flux ratio and Hall parameter. The drift-diffusive model of magnetized electrons fails in a parametric region that includes parts of the negative sheath regime. In the case of the Hall parameter vanishing near the electrode and a weakly collisional plasma, a quasisonic, quasineutral plateau forms next to the sheath edge
Physical ageing of a PU based shape memory polymer: influence on their applicability to the development of medical devices.

The variation in the properties of polymeric materials through ageing has considerable implications, since it affects the performance of any associated devices. Specially in the case of implantable devices with shape memory, any change in the switching temperature can give rise to problems in the thermal activation of the geometrical changes necessary to treat certain pathologies.This paper presents a study about the physical ageing of a polyurethane based shape memory polymer, SMP, at different temperatures using differential scanning calorimetry, DSC, and microhardness, MH, tests. The benefits of the combinated application of both testing techniques is shown, since DSC tests give information on the evolution of the glass transition temperature and the MH tests provide details of changes regarding mechanical properties
Optimization of the luminescence emission of Si nanocrystals synthesized from non-stoichiometric Si oxides using a Central Composite Design of the deposition process

Si oxide films with a controlled excess of Si were deposited on Si wafers by LPCVD using Si2H6 and O2, thermally annealed to 1100 °C for 1 h to form Si nanocrystals embedded in SiO2 and subsequently annealed at 450 °C in forming gas. The samples were characterized by Fourier transform infrared spectroscopy, spectroscopic ellipsometry and cathodoluminescence spectroscopy. The excess of Si in the as-deposited samples, ranging from 0 to 70% in volume, was obtained from the ellipsometry data analysis. After annealing at 1100 °C, the samples show a luminescence band (peaking at 665 nm) at 80 K and at room temperature which is associated to the presence of Si nanocrystals. The growth rate, the excess of Si incorporated to the films and the intensity of the luminescence band were modelled using a Face-Centered Central Composite Design as a function of the main deposition variables (pressure, 185–300 mTorr; temperature, 250–400 °C; Si2H6/O2 flow ratio, 2–5) aiming to control the growth process and the incorporation of Si in excess as well as to determine the experimental conditions that yield the samples with the maximum intensity of the luminescence emission
Biofuels in Spain: Market penetration analysis and competitiveness in the automotive fuel market

For several years the European Union (E.U.) has been promoting the use of biofuels due to their potential benefits such as the reduction of dependence on foreign energy imports (the raw materials can be produced within the E.U.), the more stable fossil fuel prices (they can replace fossil fuels on the market), the greenhouse gas (GHG) reduction (biofuels’ raw materials fix CO2 from the atmosphere) and the fact that they can represent an additional source of income for the primary sector (biofuels’ raw materials are vegetables that can be grown and harvested).\ud
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Despite the public aids (direct and indirect), biofuels are not competitive with fossil fuels at present, but it is possible that in the future the environment conditions change and biofuels might become competitive. It is difficult to assess whether this will happen or not, but it is possible to make an assessment of a future situation.\ud
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This article presents two analyses with one objective: to determine if biofuels might become competitive in the future. The first analysis examines the dependencies of two quotations which have a strong relationship with fuels: the crude oil quotation and the CO2 bond quotation. The analysis of these relationships may help to forecast the future competitiveness of biofuels. For instance, biofuels’ future competitiveness will be higher if their raw material costs are not related to crude oil quotations or if they are related in a negative way (the higher the crude oil quotations the lower the raw material biofuels’ cost). The second analysis focuses on the market penetration of biofuels in the Spanish market. There are data related to biofuels monthly consumption in Spain since 2007 and it is possible to know if biofuels are gaining market quota since the
Plasma–wall interaction in laser inertial fusion reactors: novel proposals for radiation tests of first wall materials

Dry-wall laser inertial fusion (LIF) chambers will have to withstand strong bursts of fast charged particles which will deposit tens of kJ m−2 and implant more than 1018 particles m−2 in a few microseconds at a repetition rate of some Hz. Large chamber dimensions and resistant plasma-facing materials must be combined to guarantee the chamber performance as long as possible under the expected threats: heating, fatigue, cracking, formation of defects, retention of light species, swelling and erosion. Current and novel radiation resistant materials for the first wall need to be validated under realistic conditions. However, at present there is a lack of facilities which can reproduce such ion environments. This contribution proposes the use of ultra-intense lasers and high-intense pulsed ion beams (HIPIB) to recreate the plasma conditions in LIF reactors. By target normal sheath acceleration, ultra-intense lasers can generate very short and energetic ion pulses with a spectral distribution similar to that of the inertial fusion ion bursts, suitable to validate fusion materials and to investigate the barely known propagation of those bursts through background plasmas/gases present in the reactor chamber. HIPIB technologies, initially developed for inertial fusion driver systems, provide huge intensity pulses which meet the irradiation conditions expected in the first wall of LIF chambers and thus can be used for the validation of materials too
Assessing the landscape value of public works: validation of the method in the lowlands of the middle section of the Tajo river (Spain)

This paper proposes a method of landscape characterisation and assessment of public works associated with fluvial landscapes, which is validated in the middle section of the Tajo River. In this method, a set of criteria is identified that unifies various characteristics of the landscape associated to the infrastructures. A specific weight is then assigned to each criterion in such a way as to produce a semi-quantitative value ranging from a minimum value of 0 to a maximum value of 10. Taken together, these criteria enable us to describe and assess the value of the public works selected for study, in this case helping us to evaluate the sections of the River Tajo analysed in our study area. Accordingly, the value of all the infrastructures associated to a stretch of the river covering several hundred kilometres was determined and after dividing this stretch into sections, they were compared under equivalent conditions to provide a hierarchal ranking
Grapheme-color synesthetes show peculiarities in their emotional brain: cortical and subcortical evidence from VBM analysis of 3D-T1 and DTI data

Grapheme-color synesthesia is a neurological phenomenon in which viewing achromatic letters/numbers leads to automatic and involuntary color experiences. In this study, voxel-based morphometry analyses were performed on T1 images and fractional anisotropy measures to examine the whole brain in associator grapheme-color synesthetes. These analyses provide new evidence of variations in emotional areas (both at the cortical and subcortical levels), findings that help understand the emotional component as a relevant aspect of the synesthetic experience. Additionally, this study replicates previous findings in the left intraparietal sulcus and, for the first time, reports the existence of anatomical differences in subcortical gray nuclei of developmental grapheme-color synesthetes, providing a link between acquired and developmental synesthesia. This empirical evidence, which goes beyond modality-specific areas, could lead to a better understanding of grapheme-color synesthesia as well as of other modalities of the phenomenon
Quasi-cylindrical approximation to the swirling flow in an atomizer chamber

A quasi-cylindrical approximation is used to analyse the axisymmetric swirling flow of a liquid with a hollow air core in the chamber of a pressure swirl atomizer. The liquid\ud
is injected into the chamber with an azimuthal velocity component through a number of slots at the periphery of one end of the chamber, and flows out as an anular sheet through a central orifice at the other end, following a conical convergence of the chamber wall. An effective inlet condition is used to model the effects of the slots and the boundary layer that develops at the nearby endwall of the chamber. An analysis is presented of the structure of the liquid sheet at the end of the exit orifice, where the flow becomes critical in the sense that upstream propagation of long-wave perturbations ceases to be possible. This  nalysis leads to a boundary condition at the end of the orifice that is an extension of the condition of maximum flux used with irrotational models of the flow. As is well known, the radial pressure gradient induced by the swirling flow in the bulk of the chamber causes the overpressure that\ud
drives the liquid towards the exit orifice, and also leads to Ekman pumping in the boundary layers of reduced azimuthal velocity at the convergent wall of the chamber\ud
and at the wall opposite to the exit orifice. The numerical results confirm the important role played by the boundary layers. They make the thickness of the liquid sheet at\ud
the end of the orifice larger than predicted by  rrotational models, and at the same time tend to decrease the overpressure required to pass a given flow rate through the chamber, because the large axial velocity in the boundary layers takes care of part of the flow rate. The thickness of the boundary layers increases when the atomizer\ud
constant (the inverse of a swirl number, proportional to the flow rate scaled with the radius of the exit orifice and the circulation around the air core) decreases. A\ud
minimum value of this parameter is found below which the layer of reduced azimuthal velocity around the air core prevents the pressure from increasing and steadily driving\ud
the flow through the exit orifice. The effects of other parameters not accounted for by irrotational models are also analysed in terms of their influence on the boundary\ud
layers
Morphological Functions with Parallel Sets for the Pore Space of X-ray CT Images of Soil Columns

During the last few decades, new imaging techniques like X-ray computed tomography have made available rich and detailed information of the spatial arrangement of soil constituents, usually referred to as soil structure. Mathematical morphology provides a plethora of mathematical techniques to analyze and parameterize the geometry of soil structure. They provide a guide to design the process from image analysis to the generation of synthetic models of soil structure in order to investigate key features of flow and transport phenomena in soil. In this work, we explore the ability of morphological functions built over Minkowski functionals with parallel sets of the pore space to characterize and quantify pore space geometry of columns of intact soil. These morphological functions seem to discriminate the effects on soil pore space geometry of contrasting management practices in a Mediterranean vineyard, and they provide the first step toward identifying the statistical significance of the observed differences
Optimum sizing of bare-tape tethers for de-orbiting satellites at end of mission

De-orbiting satellites at end of mission would prevent generation of new space debris. A proposed de-orbit technology involves a bare conductive tape-tether, which uses neither propellant nor power supply while generating power for on-board use during de-orbiting. The present work shows how to select tape dimensions for a generic mission so as to satisfy requirements of very small tether-to-satellite mass ratio mt/MS and probability Nf of tether cut by small debris, while keeping de-orbit time tf short and product tf ×× tether length low to reduce maneuvers in avoiding collisions with large debris. Design is here discussed for particular missions (initial orbit of 720 km altitude and 63° and 92° inclinations, and 3 disparate MS values, 37.5, 375, and 3750 kg), proving it scalable. At mid-inclination and a mass-ratio of a few percent, de-orbit time takes about 2 weeks and Nf is a small fraction of 1%, with tape dimensions ranging from 1 to 6 cm, 10 to 54 μμm, and 2.8 to 8.6 km. Performance drop from middle to high inclination proved moderate: if allowing for twice as large mt/MS, increases are reduced to a factor of 4 in tf and a slight one in Nf, except for multi-ton satellites, somewhat more requiring because efficient orbital-motion-limited electron collection restricts tape-width values, resulting in tape length (slightly) increasing too
Effect of fatty acid composition of methyl and ethyl esters on the lubricity at different humidities

Lubricity of individual fatty acid methyl or ethyl esters and biodiesel fuels has been measured using a high frequency reciprocating rig (HFRR). Tests have been carried out varying the ambient humidity to assess the effect of this parameter on the lubricity of the fuels. The European standard proposes a single humidity correction factor for all the fuels, regardless their composition. It has been proved in this study that this factor is not constant and it depends on the fuel composition. For this reason two different correlations have bee n proposed for the estimation of the humidity correction factor and normalized wear scar as a function of different fuel compositional characteristics. The influence of the water content on the lubricity and the relationship between humidity and water content of the fuel has been studied revealing that the effect of the air humidity is an indirect effect of the hygroscopy of the fuel
The origin of duo-lateral position-sensitive detector distortions

Duo-lateral position-sensitive detectors (PSD) are used for their low intrinsic distortion. This PSD was used for the gamma camera Per Operative Compact Imager (POCI) dedicated to the detection of body tumours. Besides, we developed a simulation model of this PSD. Our objective is to study the influence of the PSD and readout electronics parameters in order to improve residual spatial non-linearity, especially in detector edges. Various simulation runs based on our model were performed. The corresponding results are very close to experimental observation. Finally, this simulation is a powerfull tool for analysing PSD behaviour, in particular, cushion distortions
COPD GWAS variant at 19q13.2 in relation with DNA methylation and gene expression

Chronic obstructive pulmonary disease (COPD) is among the major health burdens in adults. While cigarette smoking is the leading risk factor, a growing number of genetic variations have been discovered to influence disease susceptibility. Epigenetic modifications may mediate the response of the genome to smoking and regulate gene expression. Chromosome 19q13.2 region is associated with both smoking and COPD, yet its functional role is unclear. Our study aimed to determine whether rs7937 (RAB4B, EGLN2), a top genetic variant in 19q13.2 region identified in genome-wide association studies of COPD, is associated with differential DNA methylation in blood (N = 1490) and gene expression in blood (N = 721) and lungs (N = 1087). We combined genetic and epigenetic data from the Rotterdam Study (RS) to perform the epigenome-wide association analysis of rs7937. Further, we used genetic and transcriptomic data from blood (RS) and from lung tissue (Lung expression quantitative trait loci mapping study), to perform the transcriptome-wide association study of rs7937. Rs7937 was significantly (FDR < 0.05) and consistently associated with differential DNA methylation in blood at 4 CpG sites in cis, independent of smoking. One methylation site (cg11298343-EGLN2) was also associated with COPD (P = 0.001). Additionally, rs7937 was associated with gene expression levels in blood in cis (EGLN2), 42% mediated through cg11298343, and in lung tissue, in cis and trans (NUMBL, EGLN2, DNMT3A, LOC101929709 and PAK2). Our results suggest that changes of DNA methylation and gene expression may be intermediate steps between genetic variants and COPD, but further causal studies in lung tissue should confirm this hypothesis
Determinants of organophosphate pesticide exposure in pregnant women: A population-based cohort study in the Netherlands

Background: In the Netherlands organophosphate (OP) pesticides are frequently used for pest control in agricultural settings. Despite concerns about the potential health impacts of low-level OP pesticides exposure, particularly in vulnerable populations, the primary sources of exposure remain unclear. The present study was designed to investigate the levels of DAP metabolites concentrations across pregnancy and to examine various determinants of DAP metabolite concentrations among an urban population of women in the Netherlands. Method: Urinary concentrations of six dialkyl phosphate (DAP) metabolites, the main urinary metabolites of OP pesticides, were determined at <18, 18-25, and >25 weeks of pregnancy in 784 pregnant women participating in the Generation R Study (between 2004 and 2006), a large population-based birth cohort in Rotterdam, the Netherlands. Questionnaires administered prenatally assessed demographic and lifestyle characteristics and maternal diet. Linear mixed models, with adjustment for relevant covariates, were used to estimate associations between the potential exposure determinants and DAP metabolite concentrations expressed as molar concentrations divided by creatinine levels. Results: The median DAP metabolite concentration was 311 nmol/g creatinine for the first trimester, 317 nmol/g creatinine for the second trimester, and 310 nmol/g creatinine for the third trimester. Higher maternal age, married/living with a partner, underweight or normal weight (BMI of <18.5 and 18.5-<25), high education, high income, and non-smoking were associated with higher DAP metabolite concentrations, and DAP metabolite concentrations tended to be higher during the summer. Furthermore, fruit intake was associated with increased DAP metabolite concentrations. Each 100 g/d difference in fruit consumption was associated with a 7% higher total DAP metabolite concentration across pregnancy. Other food groups were not associated with higher DAP metabolite concentrations. Conclusions: The DAP metabolite concentrations measured in the urine of pregnant women in the Netherlands were higher than those in most other studies previously conducted. Fruit intake was the main dietary source of exposure to OP pesticides in young urban women in the Netherlands. The extent to which DAP metabolite concentrations reflect exposure to the active parent pesticide rather than to less toxic metabolites remains unclear. Further research will be undertaken to investigate the possible effects of this relatively high level OP pesticides exposure on offspring health
Lost in Transnational Space? Migrant Farm Workers in Rural Districts

-In recent decades, theories of transnationalism have emerged as key perspectives for analysis of international migration. Drawing on Glorius and Friedrich’s (2006) model of transnationalism, the paper analyses the case of migrant farm labour in rural Norway and demonstrates how the social context of migrants’ work influences their building of various kinds of social-capital resources which are crucial for development of transnational space. The paper argues that circularity of migration is not sufficient to instigate full-fledged transculturation and hybrid identity-formation processes. In conclusion, the paper recommends that transnational theory should pay greater attention to the social contexts of migration and observe the limits of the theory’s application
Structural characterization of agmatine at physiological conditions

Abstract  The present work aims at determining the structure–activity relationships (SAR’s) which rule the biological function of agmatine (4-(aminobutyl)guanidinium, AGM), a biogenic amine produced by decarboxylation of arginine. Its structural preferences, both as an isolated molecule and in aqueous solution (namely at physiological conditions) were ascertained, by vibrational (Raman) spectroscopy coupled to theoretical (density functional) calculations. An evaluation of mitochondrial functions (membrane potential (??), mitochondrial swelling, and cytochrome c release) in rat liver mitochondria (RLM) was also carried out. The results thus obtained, coupled to the conformational analysis performed for the distinct polyamine protonation states, allowed to individualize the agmatine structures which interact with the mitochondrial site responsible for its transport and for the protection against mitochondrial permeability transition (MPT) induction, as well as to gain information on the specific mechanisms involved.http://dx.doi.org/10.1007/s11224-006-9025-