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An investigation into the effects of 63 MeV proton irradiation on high-sensitivity mid-wave infrared InGaAs/InAsSb nBn devices is performed. Three different structures with various absorber region doping profiles are irradiated and characterized to assess their impact on performance degradation. Minority carrier lifetime is measured using time-resolved photoluminescence and lifetime damage factors are assessed. The majority carrier concentration is determined via capacitance–voltage measurements and dopant introduction rates are calculated. An analysis of dark current density is performed using these material parameters, revealing a reduction in mobility with proton fluence and the emergence of a proton-induced trap energy level. Quantum efficiency is calculated at each proton fluence, and quantum efficiency damage factors show that the graded doping structure exhibits the least reduction of quantum efficiency with dose, attributed to its effective mobility enhancement. Conclusively, detector sensitivity, assessed via shot-noise limited noise-equivalent irradiance, shows that the graded doping structure is the least susceptible to high energy proton irradiation-induced performance degradation. [ABSTRACT FROM AUTHOR]

Sterile inflammation after myocardial infarction is classically credited to myeloid cells interacting with dead cell debris in the infarct zone1,2. Here we show that cardiomyocytes are the dominant initiators of a previously undescribed type I interferon response in the infarct borderzone. Using spatial transcriptomics analysis in mice and humans, we find that myocardial infarction induces colonies of interferon-induced cells (IFNICs) expressing interferon-stimulated genes decorating the borderzone, where cardiomyocytes experience mechanical stress, nuclear rupture and escape of chromosomal DNA. Cardiomyocyte-selective deletion of Irf3 abrogated IFNIC colonies, whereas mice lacking Irf3 in fibroblasts, macrophages, neutrophils or endothelial cells, Ccr2-deficient mice or plasmacytoid-dendritic-cell-depleted mice did not. Interferons blunted the protective matricellular programs and contractile function of borderzone fibroblasts, and increased vulnerability to pathological remodelling. In mice that died after myocardial infarction, IFNIC colonies were immediately adjacent to sites of ventricular rupture, while mice lacking IFNICs were protected from rupture and exhibited improved survival3. Together, these results reveal a pathological borderzone niche characterized by a cardiomyocyte-initiated innate immune response. We suggest that selective inhibition of IRF3 activation in non-immune cells could limit ischaemic cardiomyopathy while avoiding broad immunosuppression.Cardiomyocytes are the dominant initiators of a type I interferon response in the infarct borderzone. [ABSTRACT FROM AUTHOR]

A novel impurity transport model that approximates SOL turbulence as a fluctuating poloidal electric field is shown to be an acceptable replacement for the traditional approach of assigning an arbitrary radial diffusion coefficient to the impurity ions. The model is implemented in the DIVIMP impurity transport code and applied to an L-Mode tungsten divertor experiment on DIII-D. The poloidal electric field is represented as fluctuating between ±1000 V m−1 based on previous measurements. The resulting intermittent vr = E θ × BT transport causes ions to transport both into the core as well as into the far-SOL. Simultaneous agreement with estimates of the W density just inside the separatrix as well as in the far-SOL is obtained (nW ∼ 1014 m−3 and nW ∼ 1012 m−3, respectively). Prompt re-deposition of the W ions was necessary to obtain agreement (fredep ∼ 99%). We conclude that simulating impurity transport using a physics-based approximation for turbulence in the SOL, versus arbitrarily assigning diffusion coefficients, may enable better reactor scale predictions of core impurity contamination. [ABSTRACT FROM AUTHOR]

The rising concerns about CO2 levels in the atmosphere and energy dependency on non-renewable sources, such as fossil fuels, could find an integral solution in CO2 photocatalytic reduction. The present work explores two alternatives to the main hindering factors for this reaction, i.e. the reactor configuration and the photocatalyst utilized. A microreactor was designed and 3D printed, providing a cheap and versatile reaction platform. Three bismuth halide perovskites, Cs3Bi2Cl9, Cs3Bi2I9, and Cs4MnBi2Cl12, were synthesized and characterized by their band gaps (Eg); Cs3Bi2I9 presented the lowest Eg and was therefore chosen for further evaluation as potential CO2-reduction photocatalyst. Aqueous-phase photocatalytic CO2 reduction was achieved using this perovskite in the microreactor, obtaining CO as a reduction product with maximal production rates of 737 μ mol gcat−1 h−1. The reaction system was evaluated under different flow rates and light intensities. A balance between space-time and reactant feed was found to define the behavior of CO concentration and production in the microreactor. For the light intensity, it was observed that as it increased, both CO production and concentration increased due to generating more electron–hole pairs, favoring the photocatalytic reaction. With these results, Cs3Bi2I9 perovskite immobilized in the designed microreactor demonstrates having great potential as an effective CO2 photocatalytic reduction system. [ABSTRACT FROM AUTHOR]

A single radio frequency bucket of the 88-Inch Cyclotron is filled using a fast chopper located in the axial line. The bucket then accelerates until it reaches the deflector, at which point, it is extracted as a train of bunches. This phenomenon can be attributed to the characteristic multi-turn extraction of the cyclotron and, by simplifying the complex dynamics of a cyclotron, corresponds to the conceptual transfer function of the cyclotron. The confirmation of the single radio frequency bucket injection was achieved by operating the cyclotron in the third harmonic mode and observing the absence of intermediate bunches during the multiple-bunch extraction. [ABSTRACT FROM AUTHOR]

The effect of majority carrier concentration and minority carrier lifetime on the performance of mid-wave infrared ( λ cutoff = 5.5 μ m) nBn detectors with variably doped InGaAs/InAsSb type-II superlattice absorbers is investigated. The detector layer structures are grown by molecular beam epitaxy such that their absorbing layers are either undoped, uniformly doped with a target density of 4 × 1015 cm−3, or doped with a graded profile, and variable-area mesa detector arrays are fabricated. Each material's temperature-dependent minority carrier lifetime is determined by time-resolved photoluminescence, and majority carrier concentration is extracted from capacitance–voltage measurements. Detector performance is evaluated with dark current and photocurrent measurements, from which quantum efficiency and shot-noise-limited noise-equivalent irradiance are calculated. The two doped detectors have lower dark current densities compared to their undoped counterpart due to the reduction in diffusion current as well as suppression of depletion current. Although both intentionally doped devices exhibit lower minority carrier lifetimes relative to the undoped device, the device with graded doping maintains a comparable quantum efficiency to the undoped device. Ultimately, the graded doping structure exhibits the highest sensitivity with a shot noise-limited noise-equivalent irradiance of 6.3 × 1010 photons/cm2 s in low-background light conditions, within a factor of 4× of an infrared detector pixel with Rule 07 dark current density and unity quantum efficiency. A detailed analysis of the dark current, quantum efficiency, and minority carrier lifetime provides insight into the material and device design factors that must be considered to realize a device with optimal sensitivity. [ABSTRACT FROM AUTHOR]

Exposure to adverse childhood experiences or early life stress experiences (ELSs) increase the risk of non-adaptive behaviors and psychopathology in adulthood. Environmental enrichment (EE) has been proposed to minimize these effects. The vast number of methodological variations in animal studies underscores the lack of systematicity in the studies and the need for a detailed understanding of how enrichment interacts with other variables. Here we evaluate the effects of environmental enrichment in male and female Wistar rats exposed to adverse early life experiences (prenatal, postnatal, and combined) on emotional (elevated plus maze), social (social interaction chamber), memory (Morris water maze) and flexibility tasks. Our results—collected from PND 51 to 64—confirmed: 1) the positive effect of environmental enrichment (PND 28–49) on anxiety-like behaviors in animals submitted to ELSs. These effects depended on type of experience and type of enrichment: foraging enrichment reduced anxiety-like behaviors in animals with prenatal and postnatal stress but increased them in animals without ELSs. This effect was sex-dependent: females showed lower anxiety compared to males. Our data also indicated that females exposed to prenatal and postnatal stress had lower anxious responses than males in the same conditions; 2) no differences were found for social interactions; 3) concerning memory, there was a significant interaction between the three factors: A significant interaction for males with prenatal stress was observed for foraging enrichment, while physical enrichment was positive for males with postnatal stress; d) regarding cognitive flexibility, a positive effect of EE was found in animals exposed to adverse ELSs: animals with combined stress and exposed to physical enrichment showed a higher index of cognitive flexibility than those not exposed to enrichment. Yet, within animals with no EE, those exposed to combined stress showed lower flexibility than those exposed to both prenatal stress and no stress. On the other hand, animals with prenatal stress and exposed to foraging-type enrichment showed lower cognitive flexibility than those with no EE. The prenatal stress-inducing conditions used here 5) did not induced fetal or maternal problems and 6) did not induced changes in the volume of the dentate gyrus of the hippocampus. [ABSTRACT FROM AUTHOR]

In the present work, the dynamic recrystallization and microstructural evolution of the family of advanced high-strength steels Fe18MnxAl0.74C are studied, varying the aluminum content in 0, 3, 6, and 9 wt pct subjected to hot-forging treatments through three consecutive heating-deformation cycles. For characterization, X-ray diffraction (XRD), Mössbauer absorption spectroscopy (MAS), and electron backscattering diffraction (EBSD) were used. It was determined that for the steels under study, dynamic recrystallization occurs due to strain-induced boundary migration (SIBM) and is strongly influenced by the aluminum content of the alloy and its stacking failure energy (SFE), increasing that the aluminum content will generate greater nucleation sites, favoring the refinement of grains in the material and achieving a crystalline structure of random crystallographic orientation. The results are discussed throughout the article, allowing us to determine potential processing routes for advanced high-strength steels with predominantly plastic deformation mechanisms such as transformation-induced plasticity (TRIP), twinning-induced plasticity (TWIP), and microband-induced plasticity (MBIP). [ABSTRACT FROM AUTHOR]

Copyright of Lecturas de Economia is the property of Universidad de Antioquia, Facultad de Ciencias Economicas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Traditional engineering models for addressing fatigue issues are based on empirical relations between the necessary number of cycles for fatigue failures Nf and either, the nominal stress σan or the local strain εa amplitudes. The aim of the present paper is to highlight the advantages of the local strain-based approach εN for fatigue assessment of notched components over the more traditional stress-based approach σN. Since a closed form solution for the ratio between fatigue life predictions among the two methods does not exist, we have considered a hypothetical case study that included variables such as the applied stress, the stress concentration factor and the structural material, and numerically calculated the expected fatigue life according to each approach. In order to highlight the differences related with the stress-strain analysis, the applied nominal stresses (uniaxial) were limited to the elastic region where both methods use approximately the same fatigue strength curve. Additionally a unique and equal function for accounting for the mean stress effects was incorporated in both approaches. Fatigue life predictions are expressed in universal graphs of normalized stress versus the Nratio f, the latter parameter defined as the quotient between the Nf predictions according to the σN and εN approaches, considering the average values for a group of sixty structural steels at each load level. The results confirm that fatigue life predictions under the traditional stress based approach are conservative when compared to the strain based approach for all the possible scenarios described by the variables involved. c 2022 University of West Bohemia. [ABSTRACT FROM AUTHOR]

Electron beam induced current (EBIC) measurements provide a powerful tool for characterizing semiconductor based materials and devices. By measuring the current generated by the electron beam of a scanning electron microscope (SEM), EBIC allows us to extract the minority carrier diffusion length (L) and the surface recombination velocity to diffusivity ratio (S/D) of a material. When combined with information on minority carrier lifetime (τ), for instance from time-resolved photoluminescence measurements, the minority carrier mobility of the material can be extracted. However, the EBIC technique relies heavily on the accurate modeling of the carrier generation and collection process. Traditionally, this was achieved using a combination of empirical analytical expressions (and later Monte Carlo simulations) for carrier generation and analytical diffusion/ recombination expressions for carrier collection. This approach introduces significant uncertainties into the extracted material parameters. Here, we present a numerical approach to EBIC modeling which improves the spatial resolution of our model, while also retaining information regarding the relative EBIC signal as a function of incident beam energies and currents. We apply this technique to investigate the temperature dependent minority carrier mobility of InAs/InAsSb and InGaAs/ InAsSb strained layer superlattice infrared detectors and compare our results to the values obtained using external quantum efficiency measurements of the same samples. Our approach not only allows for an improvement in the uncertainty of the extracted material parameters, but also offers insight into the material and device behavior as a function of nonequilibrium carrier concentration. The technique presented here offers potentially improved characterization of not only infrared detectors, but a range of semiconductor-based devices. [ABSTRACT FROM AUTHOR]

Understanding changes in vegetation cover that affect the biophysical conditions of a region can help in formulating policies to address current and future problems of terrestrial ecosystems such as deforestation and environmental degradation. This study focuses on developing a model that forecasts the cumulative Enhanced Vegetation Index (EVI) anomalies as a tool for biophysical conditions monitoring in the Philippines. Satellite data from MODIS MYD13Q1 V6, which contains vegetation index per pixel at 16-day intervals with a resolution of 250 meters, were utilized. The cumulative EVI anomalies per instant were calculated in Google Earth Engine by aggregating the difference of a specific data point in 2011–2020 to a reference EVI mean computed from 2001–2010. The Error-Trend-Seasonality model shows that the cumulative EVI anomalies graph is non-stationary with an upward trend and seasonality. The upward trend of the cumulative EVI anomalies indicates the improvement of vegetation in the Philippines. To check the stationarity of the cumulative EVI anomalies data, the Augmented Dickey-Fuller test was utilized and the model was generated using Seasonal Autoregressive Integrated Moving Average model. Based on the analysis, the best-fit model for the cumulative EVI anomalies is SARIMA (1,1,0)(1,1,1)12 with a mean absolute percentage error (MAPE) of 13.26%. Thus, the proposed model can be used as a tool for biophysical assessment by monitoring and forecasting changes in vegetation and contribute to attaining the UN Sustainable Development Goals 2 and 15 – 'Eliminating Hunger' and 'Life on Land'. [ABSTRACT FROM AUTHOR]

Understanding changes in vegetation cover that affect the biophysical conditions of a region can help in formulating policies to address current and future problems of terrestrial ecosystems such as deforestation and environmental degradation. This study focuses on developing a model that forecasts the cumulative Enhanced Vegetation Index (EVI) anomalies as a tool for biophysical conditions monitoring in the Philippines. Satellite data from MODIS MYD13Q1 V6, which contains vegetation index per pixel at 16-day intervals with a resolution of 250 meters, were utilized. The cumulative EVI anomalies per instant were calculated in Google Earth Engine by aggregating the difference of a specific data point in 2011–2020 to a reference EVI mean computed from 2001–2010. The Error-Trend-Seasonality model shows that the cumulative EVI anomalies graph is non-stationary with an upward trend and seasonality. The upward trend of the cumulative EVI anomalies indicates the improvement of vegetation in the Philippines. To check the stationarity of the cumulative EVI anomalies data, the Augmented Dickey-Fuller test was utilized and the model was generated using Seasonal Autoregressive Integrated Moving Average model. Based on the analysis, the best-fit model for the cumulative EVI anomalies is SARIMA (1,1,0)(1,1,1)12 with a mean absolute percentage error (MAPE) of 13.26%. Thus, the proposed model can be used as a tool for biophysical assessment by monitoring and forecasting changes in vegetation and contribute to attaining the UN Sustainable Development Goals 2 and 15 – 'Eliminating Hunger' and 'Life on Land'. [ABSTRACT FROM AUTHOR]

We theoretically and experimentally investigate the application of an open-circuit voltage photodetector (VocP) architecture for mid-wave infrared (MWIR, 3–5 μm) detection and imaging. In contrast to conventional reverse-bias (RB) operation of the diode, which generates a photocurrent that is proportional to the photon irradiance, we evaluate the potential of using unbiased diodes that generate an open-circuit voltage, VOC, under illumination. The predicted Noise Equivalent Differential Temperature (NEDT) of a VocP is inferior to conventional RB when we assume an infinite well capacity and fixed integration time, but the prediction reverses when the actual well capacity of a readout integrated circuit (ROIC) is taken into account. Therefore, for a focal plane array (FPA) with a ROIC, we predict superior NEDT for the VocP. To demonstrate this concept, we fabricated and tested a basic VocP unit-cell architecture by connecting the VOC anode of a MWIR photodiode to the gate of an n-type metal-oxide semiconductor transistor that is operated in sub-threshold. Very good agreement is obtained between the analytical model and the observed drain current of the transistor over three orders of photon irradiance (1015–1018 photons/sec-cm2). The decoupling of the diode photocurrent from the integration capacitor in the circuit leads to a lower dark current that allows for longer integration times and improved sensitivity. This potentially can have a great impact on the performance and functionality of FPAs, leading to FPAs with better NEDT at a higher operating temperature, wider dynamic range, and smaller pixel size leading to larger array formats. [ABSTRACT FROM AUTHOR]

The classical multi-image super-resolution model assumes that the super-resolved image is related to the low-resolution frames by warping, convolution and downsampling. State-of-the-art algorithms either use explicit registration to fuse the information for each pixel in its trajectory or exploit spatial and temporal similarities. We propose to combine both ideas, making use of inter-frame motion and exploiting spatio-temporal redundancy with patch-based techniques. We introduce a non-linear filtering approach that combines patches from several frames not necessarily belonging to the same pixel trajectory. The selection of candidate patches depends on a motion-compensated 3D distance, which is robust to noise and aliasing. The selected 3D volumes are then sliced per frame, providing a collection of 2D patches which are finally averaged depending on their similarity to the reference one. This makes the upsampling strategy robust to flow inaccuracies and occlusions. Total variation and nonlocal regularization are used in the deconvolution stage. The experimental results demonstrate the state-of-the-art performance of the proposed method for the super-resolution of videos and light-field images. We also adapt our approach to multimodal sequences when some additional data at the desired resolution is available. [ABSTRACT FROM AUTHOR]

Purpose: Current evidence suggests the need to improve the management of breakthrough cancer pain (BTcP). For this reason, we aimed to assess the opinion of a panel of experts composed exclusively of physicians from pain units, who play a major role in BTcP diagnosis and treatment, regarding the key aspects of BTcP management. Methods: An ad hoc questionnaire was developed to collect real-world data on the management of BTcP. The questionnaire had 5 parts: (a) organizational aspects of pain units (n = 12), (b) definition and diagnosis (n = 3), (c) screening (n = 3), (d) treatment (n = 8), and (e) follow-up (n = 7). Results: A total of 89 pain-unit physicians from 13 different Spanish regions were polled. Most of them agreed on the traditional definition of BTcP (78.9%) and the key features of BTcP (92.1%). However, only 30.3% of participants used the Davies' algorithm for BTcP diagnosis. Respondents preferred to prescribe rapid-onset opioids [mean 77.0% (SD 26.7%)], and most recommended transmucosal fentanyl formulations as the first option for BTcP. There was also considerable agreement (77.5%) on the need for early follow-up (48–72 h) after treatment initiation. Finally, 65.2% of participants believed that more than 10% of their patients underused rapid-onset opioids. Conclusions: There was broad agreement among pain experts on many important areas of BTcP management, except for the diagnostic method. Pain-unit physicians suggest that rapid-onset opioids may be underused by BTcP patients in Spain, an important issue that need to be evaluated in future studies. [ABSTRACT FROM AUTHOR]

Pansharpening techniques aim at fusing a low-spatial resolution multispectral (MS) image with a higher spatial resolution panchromatic (PAN) image to produce an MS image at high spatial resolution. Despite significant progress in the field, spectral and spatial distortions might still compromise the quality of the results. We introduce a restoration strategy to mitigate artifacts of fused products. After applying the principal component analysis transform to a pansharpened image, the chromatic components are filtered conditionally to the geometry of PAN. The structural component is then replaced by the locally histogram-matched PAN for spatial enhancement. Experimental results illustrate the efficiency of the proposed restoration chain. [ABSTRACT FROM AUTHOR]

We report an experimental and theoretical study of the rheological properties of magnetic biogels consisting of fibrin polymer networks with embedded magnetite nanoparticles, swollen by aqueous solutions. We studied two types of magnetic biogels, differenced by the presence or absence of an applied magnetic field during the initial steps of cross-linking. The experiments demonstrated very strong dependence of the elastic modulus of the magnetic biogels on the concentration of the magnetic particles. We finally developed some theoretical models that explain the observed strong concentration effects. [ABSTRACT FROM AUTHOR]

Land use systems that integrate woody vegetation with livestock and/or crops and are recognised for their biodiversity and cultural importance can be termed high nature and cultural value (HNCV) agroforestry. In this review, based on the literature and stakeholder knowledge, we describe the structure, components and management practices of ten contrasting HNCV agroforestry systems distributed across five European bioclimatic regions. We also compile and categorize the ecosystem services provided by these agroforestry systems, following the Common International Classification of Ecosystem Services. HNCV agroforestry in Europe generally enhances biodiversity and regulating ecosystem services relative to conventional agriculture and forestry. These systems can reduce fire risk, compared to conventional forestry, and can increase carbon sequestration, moderate the microclimate, and reduce soil erosion and nutrient leaching compared to conventional agriculture. However, some of the evidence is location specific and a better geographical coverage is needed to generalize patterns at broader scales. Although some traditional practices and products have been abandoned, many of the studied systems continue to provide multiple woody and non-woody plant products and high-quality food from livestock and game. Some of the cultural value of these systems can also be captured through tourism and local events. However there remains a continual challenge for farmers, landowners and society to fully translate the positive social and environmental impacts of HNCV agroforestry into market prices for the products and services. [ABSTRACT FROM AUTHOR]

Agroforestry combines perennial woody elements (e.g. trees) with an agricultural understory (e.g. wheat, pasture) which can also potentially be used by a livestock component. In recent decades, modern agroforestry systems have been proposed at European level as land use alternatives for conventional agricultural systems. The potential range of benefits that modern agroforestry systems can provide includes farm product diversification (food and timber), soil and biodiversity conservation and carbon sequestration, both in woody biomass and the soil. Whilst typically these include benefits such as food and timber provision, potentially, there are benefits in the form of carbon sequestration, both in woody biomass and in the soil. Quantifying the effect of agroforestry systems on soil carbon is important because it is one means by which atmospheric carbon can be sequestered in order to reduce global warming. However, experimental systems that can combine the different alternative features of agroforestry systems are difficult to implement and long-term. For this reason, models are needed to explore these alternatives, in order to determine what benefits different combinations of trees and understory might provide in agroforestry systems. This paper describes the integration of the widely used soil carbon model RothC, a model simulating soil organic carbon turnover, into Yield-SAFE, a parameter sparse model to estimate aboveground biomass in agroforestry systems. The improvement of the Yield-SAFE model focused on the estimation of input plant material into soil (i.e. leaf fall and root mortality) while maintaining the original aspiration for a simple conceptualization of agroforestry modeling, but allowing to feed inputs to a soil carbon module based on RothC. Validation simulations show that the combined model gives predictions consistent with observed data for both SOC dynamics and tree leaf fall. Two case study systems are examined: a cork oak system in South Portugal and a poplar system in the UK, in current and future climate. [ABSTRACT FROM AUTHOR]

Abstract: This article uses a core group of three arguments to support the contention that Yellowstone National Park's thermal sites deserve special efforts to preserve them, and that this goes above and beyond the general spirit motivating the national parks. It considers arguments having to do with educational value and rarity, and an argument that relies on aesthetic constructs. For purposes of evaluating the notion of rarity, comparison is made to work on the rare saline water preserve of Mono Lake. Part and parcel of this line of debate has to do with the notion that there has been a general lack of commentary on the value of geothermal areas. The work of William J. Fritz and Robert C. Thomas, Marc Hendrix, and others is cited. [ABSTRACT FROM AUTHOR]

Summary: Objective: The objective of the study is to investigate the association of interleukin‐6 (IL6) promoter single‐nucleotide polymorphisms rs1800797 (‐597 G/A) and rs1800796 (‐572 G/C) with obesity or metabolic syndrome in Mexican‐Americans. Methods: The rs1800797 and rs1800796 single‐nucleotide polymorphisms were genotyped in Mexican‐Americans (n = 437) from South Texas, and results were correlated with measures of obesity and metabolic syndrome including body mass index, waist circumference, blood pressure, cholesterol, triglycerides, glucose, liver enzymes, plasma IL6 and high‐sensitive C‐reactive protein (hs‐CRP). Results: Significant associations were found for the rs1800796 variant with increased waist circumference, insulin resistance, lower IL6 levels and higher hs‐CRP levels. The rs1800797 variant showed no associations with metabolic traits but was associated with higher IL6 levels and lower hs‐CRP levels. Conclusions: Findings in this study support the anti‐inflammatory, anti‐obesity and glucose homeostatic roles of IL6 in Mexican‐American youth. [ABSTRACT FROM AUTHOR]

Chelate assisted oxidative addition of one equivalent of 2-phosphinothiols (2-(diphenylphosphino)ethanethiol 1, 1-(benzyloxy)-2-(diphenylphosphino)ethanethiol 2 and 2-(diphenylphosphino)-cyclohexanethiol 3) to tetrakis(triphenylphosphine)platinum(0) gives the corresponding hydrido[2-(phosphino-κP)thiolato-κS]triphenylphosphineplatinum(ii) complexes 8–10. Temperature variable NMR studies show that these complexes display a chemical equilibrium between the cis-P,P and trans-P,P geometries, strongly displaced toward the trans-P,P configuration (70–90%). XRD studies carried out on crystals of 8 indicate that although the two geometric isomers are present in solution, only the trans-P,P is obtained in the solid state. These results differ from the cis-P,N geometry observed for the related hydrido[2-(amino-κN)thiolato-κS]triphenylphosphineplatinum(ii) complexes 5–7 in solution. The crystal structures obtained for these aminothiolate hydrides show that the cis-P,N configuration is the only one observed in the solid state. Chelate assisted oxidative addition of one equivalent of 3-(diphenylphosphino)propanethiol 4 to tetrakis(triphenylphosphine)platinum(0) gives the resultant hydrido[3-(phosphino-κP)thiolato-κS]triphenylphosphineplatinum(ii) complex 11. This 3-phosphinothiolate hydride shows in solution only a trans-P,P geometry but presents two chelate ring conformational isomers. Density functional theory calculations have been used to explore the ligand-based stereoelectronic effects that are determinant in the different diastereoisomerism observed in these platinum(ii) hydrides (5–11). [ABSTRACT FROM AUTHOR]

Presents a study which reported the temporal characteristics of a Q-switched and mode-locked Neodymium (Nd)-doped yttrium-aluminum-perovskite (YAP) laser. Attempts to substitute Nd-yttrium-aluminum-garnet laser material by various crystalline hosts; Objective of experiments on Nd-YAP laser; Methods used to achieve the characterization of the temporal behavior of the laser emission.

Even after two decades, the total variation (TV) remains one of the most popular regularizations for image processing problems and has sparked a tremendous amount of research, particularly on moving from scalar to vector-valued functions. In this paper, we consider the gradient of a color image as a three-dimensional matrix or tensor with dimensions corresponding to the spatial extent, the intensity differences between neighboring pixels, and the spectral channels. The smoothness of this tensor is then measured by taking different norms along the different dimensions. Depending on the types of these norms, one obtains very different properties of the regularization, leading to novel models for color images. We call this class of regularizations collaborative total variation (CTV). On the theoretical side, we characterize the dual norm, the subdifferential, and the proximal mapping of the proposed regularizers. We further prove, with the help of the generalized concept of singular vectors, that an l∞ channel coupling makes the most prior assumptions and has the greatest potential to reduce color artifacts. Our practical contributions consist of an extensive experimental section, where we compare the performance of a large number of collaborative TV methods for inverse problems such as denoising, deblurring, and inpainting. [ABSTRACT FROM AUTHOR]

Background: The sleep apnea-hypopnea syndrome is defined by a pathologic number of respiratory events during sleep (the apnea-hypopnea index, defined as the number of apnea and hypopnea episodes per hour) and daytime symptoms (mostly, excessive sleepiness). In patients with the sleep apnea syndrome, treatment with continuous positive airway pressure (CPAP) normalizes both the apnea-hypopnea index and diurnal symptoms. However, the effect of CPAP in persons with a pathologic apnea-hypopnea index without daytime sleepiness is unclear.Objective: To investigate the short-term effects of CPAP on quality of life, objective sleepiness, cognitive function, and arterial blood pressure in nonsleepy patients with a pathologic apnea-hypopnea index.Design: Multicenter randomized, placebo-controlled, parallel-group study.Setting: Six teaching hospitals in Spain.Patients: 55 patients with an apnea-hypopnea index of 30 or greater who did not have daytime sleepiness (Epworth Sleepiness Scale score Intervention: Patients were randomly assigned to receive optimal (n = 29) or sham (n = 25) CPAP and were observed for 6 weeks.Measurements: Quality of life, objective sleepiness (Multiple Sleep Latency Test score), cognitive function, and arterial blood pressure.Results: The intervention and control groups were similar in terms of mean (+/-SE) age (54 +/- 2 vs. 52 +/- 2 years), apnea-hypopnea index (54 +/- 3 vs. 57 +/- 4), Epworth Sleepiness Scale score (7.0 +/- 0.4 vs. 7.0 +/- 0.4) and adherence to CPAP treatment (5.0 +/- 0.4 vs. 4.0 +/- 0.5 hours/d). Other variables, such as quality of life, cognitive function, and arterial blood pressure, were also similar in both groups before treatment. After 6 weeks of CPAP or sham CPAP, none of these variables changed significantly.Conclusion: In patients with an apnea-hypopnea index of 30 or greater and no subjective daytime sleepiness, CPAP does not modify quality of life, objective sleepiness, vigilance, attention, memory, information processing, visuomotor coordination, or arterial blood pressure. Treatment with CPAP is therefore not indicated in nonsleepy patients with a pathologic apnea-hypopnea index. [ABSTRACT FROM AUTHOR]

The fatigue crack growth rates curves of engineering materials depend on two parameters. In addition to the dependence on the classical stress intensity factor (SIF) range Δ K, there is a dependence on the mean load (or mean SIF), mainly in the near-threshold region. The present paper provides some useful suggestions and good practices for using three of the current available methods to reduce this second dependence through the use of tuning constants. The methods considered here are the Elber, Walker and Vasudevan (or unified approach). For each approach, multiple regression analyses are performed on experimental data from the literature, and the correlations in two and three dimensions are graphically analyzed. Numerical examples of crack growth analysis for cracks growing under nominal stresses of constant amplitude in single-edge and notch/hole geometries are performed, assuming an identical material component to that of the available experimental data. The resulting curves of crack size versus number of cycles ( a versus N) are then compared. All three models gave approximately the same ( a versus N) curves in both geometries. Differences between the behaviors of the ( a versus N) curves in both geometries are highlighted, and the reasons for these particular behaviors are discussed. [ABSTRACT FROM AUTHOR]

Background: Despite a growing consensus on the feeding practices associated with healthy eating patterns, few observational studies of maternal feeding practices with young children have been conducted, especially in low-income populations. The aim of this study was to provide such data on a low income sample to determine the degree to which observed maternal feeding practices compare with current recommendations. Methods: Eighty low-income mothers and their preschool children were videotaped at dinner in their homes. Mothers were chosen from a larger study to create a 2 X 2 X 2 design: maternal ethnicity (African American vs. Latina) by child gender by child weight status (healthy weight vs. overweight/obese). Observers coded videotapes for a range of maternal feeding strategies and other behaviors. Results: Many mothers spent considerable time encouraging eating—often in spite of the child's insistence that he or she was finished. Mothers talked little about food characteristics, rarely referred to feelings of hunger and fullness, and made more attempts to enforce table manners than to teach eating skills. Latina mothers showed higher levels of teaching eating skills and encouraging their children to eat; African American mothers showed higher levels of enforcing table manners and getting children to clear their plates. Mothers of boys used more unelaborated commands and less questions/suggestions than mothers of girls. Finally, compared to mothers of overweight/obese children, mothers of healthy weight children showed higher levels of encouraging eating and lower levels of discouraging eating. Conclusions: Most of the mothers in this study did not engage in feeding practices that are consistent with current recommendations. They did this, despite the fact that they knew they were being observed. These results should be used to inform future research about the motivations behind mothers' feeding practices and the development of interventions by helping identify areas in greatest need of change. [ABSTRACT FROM AUTHOR]

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A letter to the editor is presented which discusses the examination of the presence of myelodysplastic syndrome (MDS)-associated phenotypic alterrations (MDS-PAs) in bone marrow (BM) samples from newly diagnosed patients referred immunophenotypic investigation of plasma cell (PC) neoplasia.

Pansharpening refers to the fusion process of inferring a high-resolution multispectral image from a high-resolution panchromatic image and a low-resolution multispectral one. In this paper we propose a new variational method for pansharpening which incorporates a nonlocal regularization term and two fidelity terms, one describing the relation between the panchromatic image and the high-resolution spectral channels and the other one preserving the colors from the low-resolution modality. The nonlocal term is based on the image self-similarity principle applied to the panchromatic image. The existence and uniqueness of minimizer for the described functional is proved in a suitable space of weighted integrable functions. Although quite successful in terms of relative error, state-of-the-art pansharpening methods introduce relevant color artifacts. These spectral distortions can be significantly reduced by involving the image self-similarity. Extensive comparisons with state-of-the-art algorithms are performed. [ABSTRACT FROM AUTHOR]

In parallel to the direct contribution to the procurement phase of ITER and Broader Approach, CEA has initiated research & development programmes, accompanied by experiments together with a significant modelling effort, aimed at ensuring robust operation, plasma performance, as well as mitigating the risks of the procurement phase. This overview reports the latest progress in both fusion science and technology including many areas, namely the mitigation of superconducting magnet quenches, disruption-generated runaway electrons, edge-localized modes (ELMs), the development of imaging surveillance, and heating and current drive systems for steady-state operation. The WEST (W Environment for Steady-state Tokamaks) project, turning Tore Supra into an actively cooled W-divertor platform open to the ITER partners and industries, is presented. [ABSTRACT FROM AUTHOR]