bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isolation and Enrichment of Spermatogonial Stem Cells From Human Testis Tissues
Authors: Guo Jingtao , Cairns Bradley R. 
Published: January 2019

AbstractThis article describes a protocol for isolating human spermatogonial stem cells (hSSCs) from human testis tissues, which can be utilized for further characterization. Human testis tissues are first subjected to mechanical separation, enzymatic digestion, and physical filtering, yielding a single testicular cell suspension. SSCs or other cell types of interest can be sorted out via different enrichment approaches using selected cell surface markers (e.g., magnetic‐activated cell sorting, MACS). Those enriched cells can further be used for different purposes, including cell culture, RNA sequencing, and other genomics‐based profiling, which allow for further characterization of their properties. © 2019 by John Wiley & Sons, Inc.
Performance analysis of uplink massive MIMO systems with variable‐resolution ADCs using MMSE and MRC detection
Authors: Xiong Youzhi , Zhang Zhongpei , Wei Ning , Li Binrui , Chen Yang 
Published: January 2019

AbstractIn this paper, we analyze the performance of uplink massive multiple‐input–multiple‐output (MIMO) systems with variable‐resolution analog‐to‐digital converters (ADCs), ie, each receive antenna uses a pair of ADCs with arbitrary resolution. Given that the minimum mean square error (MMSE) or the maximum ratio combining (MRC) detection can be employed at the base station (BS); using perfect channel state information (CSI) and results from the random matrix theory, we first derive the closed‐form approximate expression of sum achievable rate for these two type detectors, respectively. Suppose that only imperfect CSI is available at the BS. We then provide a scheme to estimate the equivalent channel based on the classical linear MMSE technique and derive the sum achievable rate using the estimated equivalent channel. Moreover, to improve the system performance, we take the impacts of channel estimation error and quantization noise into account and achieve the corresponding analytical results. Finally, simulation results are presented to validate our theoretical analysis and provide some insights on the massive MIMO systems with variable resolution ADCs. Additionally, for the MMSE and MRC detector with perfect and imperfect CSI in the considered architecture, the trade‐off between the spectral efficiency and the energy efficiency is investigated as well.
Can skewness of the futures‐spot basis predict currency spot returns?
Authors: Jiang Xue , Han Liyan , Yin Libo 
Published: January 2019

AbstractThis paper examines the relationship between skewness of the futures‐spot basis and expected currency spot returns. The empirical results show that the expected spot returns are negatively correlated with the basis skewness. We find that the basis skewness exhibits statistically significant in‐sample and out‐of‐sample forecasting power. Furthermore, the basis skewness beat the random walk (without drift) in economic measures. The impacts of the basis skewness on spot returns barely vary with time and have no structural breaks. We also find that the basis skewness can really improve the predictability of spot returns, even when the futures‐spot basis is considered.
Geochemical and zircon U–Pb–Hf isotopic study of Early Cretaceous A‐type rhyolites in Hong Kong: Implications for Palaeo‐Pacific Plate subduction
Authors: Jiang Yang , Zhao Xilin , Yu Shengyao , Xing Guangfu , Yang Zhuliang , Shen Jialin , Xu Mingzuan , Wang Cunzhi , Zhu Qingbo , Jin Guodong 
Published: January 2019

Hong Kong is located at the southern margin of a Mesozoic igneous belt in Southeast China, where voluminous magmatism formed during the Early Jurassic to Early Cretaceous. The final phase of volcanism formed the rhyolitic High Island Formation, which shows geochemistry similar to A‐type granite. For example, these rocks have high content of SiO2and alkali (e.g., high K2O + Na2O, with K2O/Na2O ratios greater than 1.0) and are characterized by weakly enrichment in high‐field‐strength elements (HFSEs) and rare‐earth elements (REEs) (except for Eu) and extreme depletion of Ba, Sr, P, Ti, and Eu, with high 10,000× Ga/Al ratios. Zircon U–Pb dating for three porphyroclastic rhyolite samples from the High Island Formation yielded weighted mean206Pb/238U ages of 140.0 ± 0.8, 139.8 ± 0.7, and 139.1 ± 1.1 Ma. These zircons haveεHf(t) values of −9.0 to +0.4, with two‐stage Hf model ages (TDM2) of 1,763–1,172 Ma, indicating a magma source that involved melting of predominantly Palaeoproterozoic to Mesoproterozoic continental crust with a minor juvenile mantle component. The ~140 Ma A‐type magmas in Hong Kong area were probably formed in response to rollback and/or break‐off of the Palaeo‐Pacific Plate. Previous studies indicate that the tectonic transformation from the Palaeo‐Tethys to Palaeo‐Pacific tectonic domain occurred at >165 Ma. Hong Kong underwent a repeated slab subduction and rollback process involving (a) Palaeo‐Pacific Plate subduction formed I‐type granites and continental margin arc volcanic rocks at 165–161 Ma; (b) slab rollback lead to the formation of A‐type granites at 161–159 Ma with minor magmatism formation during the rollback stage at ~159–148 Ma; (c) renewed slab subduction formed continental margin arc rocks at 148–141 Ma; and (d) renewed slab rollback resulted in the formation of A‐type volcanic rocks at 141–139 Ma (e.g., High Island Formation).
Pharmacological basis for sedative and hypnotic like effects of Pyrus pashia using in vivo experimental models
Authors: Ain Quratul , Khan Haroon 
Published: January 2019

ObjectivePyrus pashia has traditionally been used as a therapeutic agent including sedative. In this regard, hydroethanolic extract of Pyrus pashia (HEPP) was screened for phytochemical investigation, acute toxicity, and sedative‐hypnotic activity to provide a scientific rationale to its ethno‐medicinal uses.MethodsMice were used in acute toxicity test; sedative potential was observed in open field test while thiopental‐induced sleeping time and barbiturate‐induced sleeping time tests were used for the assessment of hypnotic like effects of HEPP. Various phytochemical groups were detected in preliminary phytochemical tests.ResultsIn acute toxicity study, the extract was found safe up to 1g/kg while the extract caused 50% death at 1500 mg/kg. In all animal models, the extract had shown sedative and hypnotic effects but the most significant effect observed at increased dose in comparison with standard diazepam‐treated group. In open field test, the extract at doses of 200 and 400 mg/kg, there is mild decrease in number of lines crossed by tested animals (mice) while significant reduction shown at 600 mg/kg compared with diazepam‐treated group at dose 0.5 mg/kg. In phytochemical investigation HEPP subjected to different phytochemical tests. From the thoroughly study, it is revealed that these constituents mainly participating in sedation and hypnosis.ConclusionsThe results of the present study showed significant sedative‐hypnotic effects of the HEPP in mice and that the central benzodiazepine receptors are involved in the sedative‐hypnotic effects of this plant.
Investigating inappropriate admissions and hospitalizations in Yasuj educational hospitals based on appropriateness evaluation protocol (AEP): A case study in the internal and surgical wards
Authors: Rahimi Hamed , Ostovar Rahim , Vali Leila , Angha Parvin 
Published: January 2019

SummaryBackgroundExamining the conditions for hospital admission and its appropriateness, and continuous investigation of hospital services are important issues that can improve resource productivity, service quality, and hospital efficacy. So, the present study was conducted to determine the appropriateness of the services provided in Yasuj educational hospitals.MethodsThis descriptive‐analytical study was carried out on 204 hospitalized patients who were selected through multistage quota sampling in 2016. The appropriateness evaluation protocol (AEP) was used to collect the data. Analytical tests such as paired t‐test, chi‐square test, and Fisher's exact test were used to determine the relationship between appropriate and inappropriate admission and hospitalization and demographic characteristics. The data were analyzed using the SPSS18 statistical software.ResultsA total of 980 days of stay were evaluated, and according to the AEP, 35 days of hospitalization were considered inappropriate (3.57%). The mean hospitalization duration was 6/16 ± 5/53 days. The results showed that inappropriate admission and hospitalization rates were respectively 0.6% and 13.8%.ConclusionUnnecessary admissions and hospitalizations can be considered as one of the challenges of the health system. Reducing unnecessary hospitalization will increase hospital productivity, reduce the waiting list and hospitalization costs, and also reduce the risk of exposure to hospital infections. In order to prevent inappropriate admissions and unnecessary hospitalizations, special measures can be taken, including the use of clinical guidelines, modification of the discharge process, and modification of the lower levels of the service providing system.
Economic sanctions and child HIV
Authors: Kim Yiyeon 
Published: January 2019

SummaryApproximately 1.8 million children under age 15 were living with HIV. This study is the first to empirically examine the impact of sanctions on children's new HIV infection and AIDS‐related death rates. Using sanction and HIV/AIDS data that are available for 71 developing countries from 1990 to 2012, this study reveals that sanctions increase children's new HIV infection and their AIDS‐related death rates. This study increases understanding about the consequences of sanctions, especially their effect on a marginalized population and is in line with previous literature. The significant impacts of sanctions on children's HIV/AIDS suggest that the leader in a country targeted by sanctions needs to consider extending programs to respond to children's HIV/AIDS both during sanctioning and after it is lifted.
An analysis of potential bias in the sensitivity of toxicity data used to construct sensitivity distributions for copper
Authors: Croteau Kelly , Santore Robert , DeForest David , Baken Stijn 
Published: January 2019

Abstract

Since the mid-1970s, thousands of studies have evaluated the toxicity of various chemicals to aquatic organisms. Results from many of these studies have been used to develop species sensitivity distributions (SSDs) or genus sensitivity distributions (GSDs) for deriving water quality guidelines. Recently, there has been more emphasis on evaluating the toxicity of chemicals to sensitive organisms rather than the entire range of sensitivities. The SSD approach is intended to inform the derivation of guidelines for the protection of all species, not just those that were included in the SSD. The overemphasis of the more sensitive end of the SSD can contribute to a skew in the observed distribution such that the shape of the distribution is distorted from what it would be if all species could be tested, which ultimately affects the derived guideline value. The freshwater acute Cu GSD derived by the US Environmental Protection Agency (USEPA) is one that exemplifies this trend, with one-third of the genera in the GSD belonging to only 3 taxonomic families, all of which are nearer to the sensitive end of the distribution. The stronger representation of the more sensitive families does not seem to mirror the overall abundance of species within those families in nature. This tendency toward testing sensitive organisms is not seen in the chronic Cu SSD. In the present study, Cu toxicity literature is reviewed and long-term trends in the availability of toxicity information for species of varying sensitivity are examined. As part of the present review, the apparent bias that favors the publication of toxicity data for sensitive taxa is demonstrated, and implications for the representativeness of SSDs and their use in developing water quality guidelines are discussed. Integr Environ Assess Manag 2019;00:000–000. © 2019 SETAC
Protein Corona Mediated Stealth Properties of Biocompatible Carbohydrate‐based Nanocarriers
Authors: Simon Johanna , Christmann Sarah , Mailänder Volker , Wurm Frederik R. , Landfester Katharina 
Published: January 2019

AbstractCarbohydrates possess ideal properties for the synthesis of biocompatible nanocarriers. Therefore, hydroxyethyl starch was chosen as building material to produce biodegradable nanocarriers allowing the encapsulation of drugs. A mandatory feature for the successful application of nanocarriers in drug delivery is to avoid non‐specific uptake into macrophages. Todays’ gold standard is poly(ethylene glycol) (PEG) attached onto the surface of nanocarriers. As alternatives, we synthesize completely carbohydrate‐based nanocarriers by functionalizing the surface with different sugar derivatives (hydroxyethyl starch, dextran, or glucose) via copper‐free click reaction. Studying the interaction of sugar‐modified nanocarriers and plasma proteins indicates a strong enrichment of adsorbed ‘stealth’ proteins (clusterin) which are also identified on PEGylated nanocarriers. Cellular uptake studies proved that there is no unspecific interaction between carbohydrate‐ modified nanocarriers and phagocytic cells, herby underlining the stealth properties.
Cold stress results in sustained locomotor and behavioral deficits in Drosophila melanogaster
Authors: Garcia Mark J. , Teets Nicholas M. 
Published: January 2019

AbstractTolerance of climatic stressors is an important predictor of the current distribution of insect species, their potential to invade new environments, and their responses to rapid climate change. Cold stress causes acute injury to nerves and muscles, and here we tested the hypothesis that low temperature causes sublethal deficits in locomotor behaviors that are dependent on neuromuscular function. To do so, we applied a previously developed assay, the rapid iterative negative geotaxis (RING) assay, to investigate behavioral consequences of cold stress in Drosophila melanogaster. The RING assay allows for rapid assessment of negative geotaxis behavior by quantifying climbing height and willingness to climb after cold stress. We exposed flies to cold stress at 0°C and assessed the extent to which duration of cold stress, recovery time, and cold acclimation influenced climbing performance. There was a clear dose‐response relationship between cold exposure and performance deficits, with climbing height and willingness decreasing as cold exposure increased from 2 to 24 hr. Following cold exposure of an intermediate duration (12 hr), climbing height and willingness gradually improved as recovery time increased from 4 to 72 hr but flies never fully recovered. Finally, cold acclimation improved overall climbing height and willingness in both untreated and cold‐stressed flies but did not prevent a reduction in climbing performance. Thus, cold stress causes deficits in locomotor and behavior that are dependent on the dose of cold exposure and persist long after the stress subsides. These results likely have implications for the ecological and evolutionary responses of insect populations to thermally variable environments.
The dark side of socialization: How and when divestiture socialization undermines newcomer outcomes
Authors: Montani Francesco , Maoret Massimo , Dufour Lucas 
Published: January 2019

SummaryThis research examines the potential downsides of divestiture socialization. We theorize that supervisor behaviors and attitudes—that is, support for authenticity and creativity expectations—moderate the different stages of a model in which newcomers' authentic self‐expression mediates the negative effect of divestiture socialization on newcomer task performance, creativity, social integration, and job satisfaction. Specifically, supervisor support for authenticity allows newcomers to express their authentic self when faced with divestiture processes, and perceived supervisor creativity expectations enable them to deploy their authentic self‐expressions to enhance their creativity. A time‐lagged, multisource study of 142 newcomer—supervisor dyads provides support for these predictions, offering notable implications for theory and practice.
Compact high‐sensitivity symmetrical integrated optical system for the detection of Raman scattering with dual channels
Authors: Fan Xian‐guang , Chen Jun , Wang Xin 
Published: January 2019

AbstractWe present here a compact symmetrical integrated optical system for the high‐sensitivity handheld Raman spectrometer. This symmetric optical system is of higher sensitivity of Raman spectrum detection by coupling collection optics to the spectrometer directly, reflecting excitation laser incident at 45° while efficiently passing the longer Raman‐shift wavelength with two long‐pass dichroic laser‐flat beam‐splitters placed in parallel. Three aspherical collecting lens with high‐numerical aperture were used to collect Raman scattering. Four protected silver plane mirrors, two right‐angle mirrors, and an aspherized achromatic focusing lens were used to focus Raman scattering into the slit on the collecting optical path. The Raman scattering light from the entrance slit were collimated to a blazed holographic reflective grating by an achromatic doublet lens, and the two diffraction lights with different orders were focused onto the two different surface of charge‐coupled device with two broadband dielectric coating concave mirrors, respectively. The coma and astigmatism of this optical system are decreased by optimizing the optical structure parameters. The finer Raman spectrum of samples can be obtained through the second order diffraction spectrum acquisition channel, whereas the first order diffraction channel covers almost all the Raman spectrum range. The tested spectrum of Benzoyl peroxide indicates that this symmetric integrated optical system with three collecting channels and double‐detecting channels has a higher sensitivity, higher signal‐to‐noise ratio, and finer Raman spectrum than the conventional portable Raman spectrometer with independent probe and single detection channel.
Extending storage potential of de‐hulled fresh pistachios in passive‐modified atmosphere
Authors: Sheikhi Abdollatif , Mirdehghan Seyed H , Ferguson Louise 
Published: January 2019

AbstractBackgroundThe effects of passive modified‐atmosphere packaging (passive‐MAP) on the postharvest quality of de‐hulled fresh pistachios (Pistacia vera L. cv. Kerman) stored at cold temperature (0 ± 0.5 °C) and 90 ± 1% relative humidity was investigated with fruits under ambient air condition as the control treatment. The fruit quality parameters measured included kernel firmness, color values (L*, a*, b*, h°, and C*), weight loss, fungal decay and marketability, ethylene production, respiration rate, and sensory characteristics at 0, 30, 60, and 105 days of storage. The carbon dioxide (CO2) and oxygen (O2) concentrations in the package headspace were monitored during storage.RESULTSA modified atmosphere of 0.95–3.35% O2 and 23.17–29.82% CO2 was achieved in the passive‐MAP treatment. Fruit respiration rates increased significantly relative to controls throughout storage (P ≤ 0.01). However, storage had no significant effect on ethylene production rates. Additionally, passive‐MAP‐stored fruits maintained firmness, shell lightness, kernel color, and sensory quality with minimum weight loss and fungal decay, compared with the control.CONCLUSIONThese results demonstrate storage life of fresh pistachios in passive‐MAP can be extended up to 105 days, compared with 30 days in ambient conditions. © 2019 Society of Chemical Industry
Enzymatic production of emulsifying whey protein hydrolysates without the need of heat inactivation
Authors: Ewert Jacob , Luz Anja , Volk Veronika , Stressler Timo , Fischer Lutz 
Published: January 2019

AbstractBACKGROUNDOne possible way to modify the emulsifying properties of whey proteins is by enzymatic hydrolysis. However, most studies covering the influence of the hydrolysis on whey proteins used a heating step (>65 °C) to inactivate the enzyme. This leads to irreversible product changes, like protein denaturation and increased viscosity. Here, the objective was to investigate the single effect of hydrolysis on the emulsifying properties of whey proteins under conditions without a temperature step for enzyme inactivation. Therefore, two acidic peptidase preparations (Maxipro AFP, Protease AP‐30L) differing in their peptidase composition were investigated and applied at 45 °C and pH 2.75. The enzyme inactivation was realized by a simple shift to pH 7.0.RESULTSAfter the pH shift, no activity or further hydrolysis was measurable. For the products, no differences (assuming P > 0.05) regarding the emulsifying properties were detected between the two peptidase preparations used. The emulsifying properties of the whey protein isolate hydrolysates produced increased (i.e. half‐life >71%) until a degree of hydrolysis of 1.1%. This indicated that the endopeptidase (aspergillopepsin I) present in both preparations was determining the emulsifying properties. As a plus, the presence of exopeptidases in Protease AP‐30L compared with Maxipro AFP reduced the bitterness of the hydrolysate (−50%).CONCLUSIONThe application of acidic endo‐ and exopeptidases enables the production of emulsifying whey protein isolate hydrolysates at high protein concentrations (≥10%) without a commonly used heat inactivation step. The presence of exopeptidases in acidic peptidase preparations is favorable, due to the improved taste. © 2019 Society of Chemical Industry
The effect of diet of the donor cows on in vitro measurements of methane production from wheat and corn incubated in various forage‐to‐grain ratios
Authors: Alvarez‐Hess Pablo S , Moate Peter J , Williams S Richard O , Jacobs Joe L , Beauchemin Karen A , Durmic Zoey , Hannah Murray C , Eckard Richard J 
Published: January 2019

AbstractBACKGROUNDSupplementation of ruminant diets with wheat and corn grains influences ruminal fermentation. In vitro fermentation is a methodology that can be used to screen feeds for their potential to produce enteric methane. However, there is evidence that the diet of the donor cows could impact the results of in vitro analysis. This research investigated the in vitro fermentation of wheat and corn grain when incubated in ruminal fluid from cows fed different grain types and different forage‐to‐grain ratios.RESULTSThe type of grain fed to the donor cows, as well as forage‐to‐grain ratio, affected the outcome of fermentation of wheat and corn grain. Differences in methane production (MP) between grains were only observed when incubated with ruminal fluid adapted to each specific grain type. Increasing proportions of wheat but not of corn decreased in vitro MP in a linear manner compared with MP produced from forage only.CONCLUSIONSWheat grain has a greater in vitro antimethanogenic effect than corn. However, to detect the different fermentations between wheat and corn, grains should be incubated in ruminal fluid from cows adapted to that specific grain type. © 2019 Society of Chemical Industry