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A micromechanical model for efective conductivity in granular electrode structures

Acta Mechanica Sinica 2013年第5期29卷 682-698页

作者： Julia Ott Benjamin Vlker Yixiang Gan Robert M.mc Meeking Marc Kamlah Institute of Applied Materials Karlsruhe Institute of Technology76131 Karlsruhe Germany Department of Mechanical Engineering University of CaliforniaSanta BarbaraCA 93106 USA School of Civil Engineering The University of SydneyNSW 2006 Australia Materials Department University of CaliforniaSanta BarbaraCA 93106 USA School of Engineering University of AberdeenKing’s CollegeAberdeenAB24 3UE Scotland UK INM-Leibniz Institute for New Materials Campus D22 66123 Saarbrücken Germany

Optimization of composition and microstructure is important to enhance performance of solid oxide fuel cells （SOFC） and lithium-ion batteries （LIB）. For this, the porous electrode structures of both SOFC and LIB are modeled as a binary mixture of electronic and ionic conducting particles to estimate effective transport properties. Particle packings of 10000 spherical, binary sized and randomly positioned particles are created numerically and densified considering the different manufacturing processes in SOFC and LIB： the sintering of SOFC electrodes is approximated geometrically, whereas the calendering process and volume change due to intercalation in LIB are modeled physically by a discrete el- ement approach. A combination of a tracking algorithm and a resistor network approach is developed to predict the con- nectivity and effective conductivity for the various densified structures. For SOFC, a systematic study of the influence of morphology on connectivity and conductivity is performed on a large number of assemblies with different compositions and particle size ratios between 1 and 10. In comparison to percolation theory, an enlarged percolation area is found, es- pecially for large size ratios. It is shown that in contrast to former studies the percolation threshold correlates to varying coordination numbers. The effective conductivity shows not only an increase with volume fraction as expected but also with size ratio. For LIB, a general increase of conductivity during the intercalation process was observed in correlation with increasing contact forces. The positive influence of cal- endering on the percolation threshold and the effective conductivity of carbon black is shown. The anisotropy caused by the calendering process does not influence the carbon black phase.

关键词： Granular electrode structures Effective conductivity - Percolation

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Placental accommodations for transport and metabolism during intra-uterine crowding in pigs

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Journal of Animal Science and Biotechnology 2015年第2期6卷 163-176页

作者： Jeffrey L Vallet Anthony K mc Neel Jeremy R Miles Bradley A Freking U.S. Department of Agriculture Agricultural Research Service U.S. Meat Animal Research CenterState Spur 18D Clay Center NE 68933 USA

Litter size and birth weights are limited by uterine capacity, defined as the ability of the uterus to maintain the appropriate development of some number of conceptuses. Uterine capacity is the result of the combined effects of uterine, placental and embryo/fetal function. The number of living conceptuses that the uterus is capable of supporting is greater during early gestation compared to later gestation. Plots of log fetal weight versus log placental weight also indicate that fetal weights are less sensitive to reduced placental weight （and therefore reduced intrauterine space） in early gestation compared to late gestation. However, even in late gestation, mechanisms still exist that maintain fetal growth when the size of the placenta is reduced. One such mechanism is likely to be improved development of the folded placental-epithelial/maternal-epithelial bilayer. Fold depth, and therefore the maternal fetal interactive surface, increases as gestation advances and is greater in placenta from smal fetuses. On the fetal side of the placenta, the epithelial bilayer is embedded in stromal tissue. Glycosaminoglycans are major components of stroma, including hyaluronan and heparan sulfate. Hyaluronidases and heparanases are present within placental tissues, and likely play roles in modification of stromal components to facilitate fold development. Glycosaminoglycans are polymers of forms of glucose （glucosamine, glucuronic acid, iduronic acid） suggesting that glycosaminoglycan synthesis may compete with the glucose needs of the developing fetus. Pig conceptuses are fructogenic, such that a substantial portion of glucose transferred from mother to fetus is converted to fructose. Fructose is an intermediate product in the synthesis of glucosamine from glucose, and glucosamine is linked to regulation of trophoblast cell proliferation through regulation of mTOR. These findings suggest a link between glucose, fructose, glucosamine synthesis, GAG production, and placental m

关键词： Glycosaminoglycans Nutrient transport Placenta

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Mineral concentrations of chickpea and lentil cultivars and breeding lines grown in the *** Northwest

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The Crop Journal 2018年第3期6卷 253-262页

作者： George J.VANDemark Michael A.Grusak Rebecca J.mc Gee USDA-ARS Grain Legume Genetics and Physiology Research Unit USDA-ARS Red River Valley Agricultural Research Center

Diseases and health complications caused by mineral deficiencies afflict billions of people globally. Developing pulse crops with elevated seed mineral concentrations can contribute to reducing the incidence of these deficiencies. The objectives of this study were to estimate variance components conditioning seed mineral concentrations of chickpea and lentil grown in Washington and Idaho, determine correlations between different mineral concentrations and between mineral concentrations and yield, 100-seed weight, and days to flowering, and compare seed mineral concentrations between chickpeas and lentils grown in adjacent plots. Genotype effects, although significant in chickpea and lentil for all minerals except selenium, tended to be minimal compared to location, year, and their interaction effects. In both chickpeas and lentils high positive correlations were observed between seed concentrations of phosphorus and potassium, phosphorus and zinc, and potassium and zinc. Correlations between mineral concentration and yield, and mineral concentration and days to 50% flowering were similar for chickpeas and lentils across the majority of minerals. These results may reflect similarities between the two crops in physiological processes for mineral uptake and partitioning. Lentils had higher concentrations of iron and zinc than chickpea when the two crops were grown in adjacent plots,whereas chickpeas had higher concentrations of calcium and manganese. Plant genotypes that are more efficient at obtaining minerals from growing environments will be useful as parental materials to develop improved chickpea and lentil cultivars that have good yield potential coupled with high seed mineral concentrations.

关键词： Chickpea Lentil Mineral Nutrition Pulse

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Spatio-temporal analysis of flowering using Li DAR topography

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Journal of Geographical Sciences 2017年第1期27卷 62-78页

作者： HART Samantha MIKHAILOVA Elena POST Christopher mc MILLAN Patrick SHARP Julia BRIDGES William Department of Forestry and Environmental Conservation Clemson University SC 29634 USA Department of Mathematical Sciences Clemson University SC 29634 USA

Spatio-temporal patterns of flowering in forest ecosystems are hard to quantify and monitor. The objectives of this study were to investigate spatio-temporal patterns（e.g. soilssimple slope classesslope aspectand flow accumulation） of flowering around Lake IssaqueenaSouth Carolina（SCUSA） using plant-flowering database collected with GPS- enabled camera（stored in Picasa 3 web albums and project website） on a monthly basis in 2012 and Li DAR-based topography. Pacolet fine sandy loam had the most flowering plantsfollowed by Madison sandy loamboth dominant soil types around the lake. Most flowering plants were on moderately steep（17%–30%） and gently sloping（4%–8%） slopes. Most flowering plants were on west（247.5°–292.5°）southwest（202.5°–247.5°）and northwest（292.5°–337.5°） aspects. Most flowering plants were associated with minimum and maximum flows within the landscape. Chi-square tests indicated differences in the distributions of the proportions of flowering plants were significant by soil typeslopeaspectand flow accumulation for each month（February-November）for all months（overall）and across months. The Chi-square test on area-normalized data indicated significant differences for all months and individual differences by each month with some months not statistically significant. Cluster analysis on flowering counts for nine plant families with the most flowering counts indicated no unique separation by clusterbut implied that the majority of these families were flowering on strongly sloping（9%–16%） slopeson southwest（202.5°–247.5°） aspectsand low flow accumulation（0–200）. Presented methodology can serve as a template for future efforts to quantify spatio-temporal patterns of flowering and other phenological events.

关键词： aspect flow accumulation Geographic Information Systems(GIS) phenology soils

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Synthesis and Characterization of Mixed Al+AlN Nanoparticles

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Journal of Materials Science & Technology 1997年第4期13卷 309-311页

作者： Sun, XC Yang, mc Ye, F Sun, XK Wei, WD Yu, YD Ping, DH CHINESE ACAD SCI INST MET RESATOM IMAGING SOLIDS LABSHENYANG 110015PEOPLES R CHINA

Mixed Al+AlN nanoparticles were synthesized by an active plasma-metal reaction method. Mean particle size of the mixed Al+AlN nanoparticles is about 30-50 nm. Defects were found in some AIN particles. Moreover, the AIN ratio and its particle size in mixed Al+AlN nanoparticles obtained in different atmospheres (N-2+Ar) increase with increasing N-2 particle pressure, and the specific surface areas of the mixed Al+AlN nanoparticles increase with the AIN ratio. The surface degradation of the Al+AlN exposed to air is estimated by the infrared absorption spectra.

关键词： Nanostructured materials

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Impact of direct and indirect heating systems in broiler units on environmental conditions and flock performance

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Journal of Integrative Agriculture 2016年第11期15卷 2588-2595页

作者： Shaun Smith Joseph Meade James Gibbons Kevina mc Gill Declan Bolton Paul Whyte UCD School of Veterinary Medicine University College Dublin Belfield Dublin 4 Ireland Teagasc Ashtown Food Research Centre Ashtown Dublin 15 Ireland

This study compared the impact of three indirect heating systems to direct gas flame heaters on a selection of flock performance and environmental indicators in commercial broiler units. No statistically significant differences（P≥0.05） were found in flock mortality rates, bird weight, water consumption, stress response, carbon dioxide, ammonia, temperature, relative humidity, litter quality, within-flock Campylobacter levels or mean Campylobacter counts when flock data from any of the three indirect heating systems were compared to flocks reared in houses with direct heating systems. Differences in litter quality were observed between upper and lower litter layers in all houses, regardless of heating type, which may have implications for bird health and welfare. Carbon dioxide concentrations in houses with direct heating systems were significantly higher than those in houses with indirect heating systems during the first 10 days of bird life（P≤0.05）. This was due to the increased use of heating systems during this period of the flock cycle. Differences in CO2 concentrations had no effect on flock performance, possibly due to the fact that concentrations did not exceed known safe levels. A statistically significant increase in stress response was observed in birds as a result of partial depopulation（thinning） within houses, irrespective of heating system type used（P≤0.05）. Stress associated with thinning may have consequences for bird welfare and food safety. In conclusion, the results of our study suggest that indirect heating systems do not appear to negatively impact on flock performance, stress response, within-flock Campylobacter levels or mean Campylobacter counts and do not appear to significantly alter environmental conditions within broiler houses when compared to houses equipped with direct heating systems. Indirect systems are a viable alternative for heating broiler houses in terms of flock performance, bird welfare and food safety.

关键词： litter quality welfare stress poultry production campylobacter environmental conditions

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Expression of perforin and granzyme B mRNA in judgement of immunosuppressive effect in rat liver transplantation

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World Journal of Gastroenterology 1999年第3期5卷 217-220页

作者： Zhang SG Wu mc Tan JW Chen H Yang JM Qian QJ Fuzhou Mil Gen Hosp Dept Hepatobiliary Surg Fuzhou 350025 Fujian Province Peoples R China Second Mil Med Univ Shanghai E Hepatobiliary Hosp Shanghai 200433 Peoples R China

AIM To explore the expression of perform andgranzyme B genes mRNA to judge the effect ofimmunosuppression in acute rejection of *** The expression of perform andgranzyme B genes mRNA was examined byreverse transcriptase-polymerase chain reaction(RT--PCR) in hamster to rat liver grafts under theimmunosuppression of cyclosporine or/andsplenectomy. Histological findings were *** Cyclosporine could obviouslydecrease the cellular infiltration, and completelyrepress the expression of mRNA for perform andgranzyme B, but could not change severehepatocyte necrosis and *** could significantly lightenhepatocyte necrosis, and completely eliminatehemorrhage, but not atfect the cellularinfiltration and the expression of perform andgranzyme B genes mRNA. Cyclosporine orsplenectomy alone could not prolong theSurvival time, however, their combination couldcompletely repress the rejection of liver *** survival time of animals were significantlyprolonged (37.1 days ). The architecture ofhepatic lobules was preserved. There was slightcellular infiltration in the portal tracts and noexpression of perform and granzyme B genesmRNA could be seen in three weeks *** Perform and granzyme B genesare valuable in judging the effect ofimmunosuppression in liver transplantation.

关键词： mRNA

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Periodic interstellar scintillation variations of PSRs J0613-0200 and J0636+5128 associated with the Local Bubble shell

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中国科学:物理学、力学、天文学英文版 2023年第11期66卷 221-232页

作者： Yulan Liu Robert A.Main Joris P.W.Verbiest Ziwei Wu Krishnakumar M.Ambalappat Jiguang Lu David J.Champion Ismael Cognard Lucas Guillemot Kuo Liu James W.mc Kee Nataliya Porayko Golam.M.Shaifullah Gilles Theureau National Astronomical Observatories Chinese Academy of SciencesBeijing100101China Fakultät für Physik Universität BielefeldBielefeld33501Germany Max-Planck-Institut für Radioastronomie Bonn53121Germany Florida Space Institute University of Central FloridaOrlandoFL32826USA Station de radioastronomie de Nançay Observatoire de ParisNançay18330France Laboratoire de Physique et Chimie de l’Environnement et de l’Espace Universitéd’OrléansOrléans45071France E.A.Milne Centre for Astrophysics University of HullHullHU67RXUK Centre of Excellence for Data Science Artificial Intelligence and ModellingUniversity of HullHullHU67RXUK Dipartimento di Fisica“G.Occhialini” Universitàdi Milano-BicoccaMilano20126Italy INAF-Osservatorio Astronomico di Cagliari Selargius(CA)09047Italy INFN Sezione di Milano-BicoccaMilano20126Italy

Annual variations of interstellar scintillation can be modelled to constrain parameters of the ionized interstellar *** a pulsar is in a binary system,then investigating the orbital parameters is possible through analysis of the orbital variation of *** observations carried out from 2011 to 2020 by the European Pulsar Timing Array radio telescopes,PSRs J0613-0200and J0636+5128 show strong annual variations in their scintillation velocity,while the former additionally exhibits an orbital *** theory and Markov-chain-Monte-Carlo methods are used to interpret these periodic *** assume a thin and anisotropic scattering screen model,and discuss the mildly and extremely anisotropic scattering *** J0613-0200is best described by mildly anisotropic scattering,while PSR J0636+5128 exhibits extremely anisotropic *** measure the distance,velocity,and degree of anisotropy of the scattering screen for our two pulsars,finding that scattering screen distances from Earth for PSRs J0613-0200 and J0636+5128 are 316_(-20)^(+28)pc and 262_(-38)^(+96)pc,*** positions of these scattering screens are coincident with the shell of the Local Bubble towards both *** associations add to the growing evidence of the Local Bubble shell as a dominant region of scattering along many sightlines.

关键词： pulsar interstellar scintillation ionized interstellar medium

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Anti-diabetic properties and bioactive compounds of Teucrium polium L.

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Asian Pacific Journal of Tropical Biomedicine 2020年第10期10卷 433-441页

作者： Ali Akbar Asghari Amin Mokhtari-Zaer Saeed Niazmand Kathleen mc Entee Maryam Mahmoudabady Department of Physiology Faculty of MedicineMashhad University of Medical SciencesMashhadIran Laboratory of Physiology Faculty of MedicineUniversitéLibre de BruxellesBrusselsBelgium Neurogenic Inflammation Research Center Mashhad University of Medical SciencesMashhadIran

Diabetes mellitus is a common metabolic disease with considerable morbidity and mortality. Untreated or improperly-treated diabetes can be associated with several long-term complications that necessitate an effective way to manage diabetes. Due to the side effects of synthetic glucose-lowering agents, alternative therapeutic modalities such as medicinal plants have attracted notable attention. Teucrium polium L. is a medicinal herb with antioxidant, antinociceptive, anti-inflammatory, hypolipidemic, hepatoprotective, and hypoglycemic properties. In vitro and in vivo studies have been conducted to characterize the anti-diabetic properties of Teucrium polium L. and its bioactive compounds. We conducted a literature study using Scopus, Pub Med, and Google Scholar including the keywords "diabetes" and "Teucrium polium". We also scanned all the references cited by the retrieved articles. According to this review, Teucrium polium administration displayed anti-diabetic effects by targeting different mechanisms and pathways, such as enhancement of insulin secretion and insulin level, improvement of oxidative damage, regeneration of pancreatic β-cells, and promotion of glucose uptake in muscle tissues by increasing GLUT-4 translocation as well as inhibiting α-amylase activity. Although Teucrium polium has been widely regarded as a traditional method, the pharmacological studies on anti-diabetic effects are not sufficient, most studies are either in-vivo or in-vitro. The preclinical and clinical studies are further required to confirm the efficacy of Teucrium polium.

关键词： diabetic protective bioactive

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Using weighted blankets in an inpatient mental health hospital to decrease anxiety

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Journal of Integrative Medicine 2021年第2期19卷 129-134页

作者： Annette L.Becklund Lisa Rapp-mc Call Jessica Nudo Annette L Becklund MSWLCSW&Associates LLCPO Box 3870Spring HillFL 34611USA Saint Leo University Saint LeoFL 33574-6665USA

Objective:Patients who are involuntarily committed to a psychiatric facility often experience anxiety or increased anxiety in response to being placed in the institutional *** weighted blanket introduced a proactive treatment *** purpose of this study was to evaluate patients’anxiety symptoms before and after weighted blanket,compared to a group that did not use a weighted blanket to control ***:This study was conducted in an inpatient mental health facility from June 10,2019,through November 7,2019,with psychiatric patients who were not actively *** were offered the choice of weighted or unweighted blankets for a 20-minute *** treatment group was comprised of individuals who had opted to use a 14-pound weighted blanket,20-pound weighted blanket or 5-pound weighted lap *** in the comparison group were active in a wider range of *** application of the blankets,pulse rate was measured using a pulse oximeter,and anxiety was measured using the Spielberger State-Trait Anxiety Inventory shortened form(STAI:Y-6).Both measures were taken again after the intervention.A two-way mixed analysis of variance(ANOVA)was run to examine the interaction effects between time(pre/post)and group(comparison/weighted blanket).Simple main effects were then further examined for the comparison/weighted blanket groups using a repeated measures *** the weighted blanket group,additional two-way mixed ANOVA was run to determine if gender or blanket weight made a statistically significant ***:There was a statistically significant difference(P<0.05)among those who used weighted blankets(n=61)and those who did not(n=61)based on the pre/post data for both the STAI:Y-6 inventory and the patients’pulse *** results of two-way ANOVA indicated a significant interaction effect between intervention time and group(P<0.001).Repeated measures ANOVA indicated a change between pre/post for the we

关键词： Weighted blanket Anxiety Mental health

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