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Ordered coalescence of nano-crystals in alkaline niobate ceramics with high remanent polarization

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Journal of Materiomics 2017年第4期3卷 267-272页

作者： Zhijian Shen Daniel Gruner Mirva Eriksson Lyubov M.Belova Ce-Wen Nan Haixue Yan Department of Materials and Environmental Chemistry Arrhenius LaboratoryStockholm University10691StockholmSweden Department of Materials Science and Engineering Royal Institute of Technology10044StockholmSweden School of Materials Science and Engineering Tsinghua UniversityBeijing100084China School of Engineering and Materials Science Queen Mary University of LondonMile End RoadLondonE14NSUK

Lead-free alkali niobates Na_(0.5)K_(0.5)NbO_(3)(NKN)ceramics,with significantly enhanced ferroelectric remanent polarization(Pr),were prepared using Spark Plasma Sintering(SPS).Three types of boundaries were observed in the ceramics,being grain boundaries between faceted grains,domain boundaries that separate ferroelectric domains inside individual grains,and nanoscale sub-grain boundaries that reveal the nano-scale mosaicity of individual *** of the sub-grain boundaries were from initial powder *** other sub-grain boundaries were built by ordered coalescence of nano-crystals during rapid SPS *** was worthwhile to emphasize that the ordered coalescence of nano-crystals in bulk ceramics during sintering takes place and completes within *** sub-grain features would disappear at higher temperature by long time *** Spark Plasma Sintering allowed us to capture this transient *** significantly enhanced ferroelectric Pr of NKN was attributed to nanoscale sub-boundaries,which stimulated the dynamics of ferroelectric domain formation and switching.

关键词： Lead-free NKN SPS Remanent polarization Ordered coalescence

案主满意度评估：一种有效的社会工作实务评估方法

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华东理工大学学报（社会科学版） 2013年第4期28卷 28-35页

作者：刘芳吴世友 Mark W.Fraser 重庆师范大学历史与社会学院重庆401331 北卡罗来纳大学教堂山分校社会工作学院美国27599

中国社会工作近年来发展迅速,社会工作实务也随之蓬勃发展,然而目前对于社会工作服务评估却尚未形成体系,现有的评估方法也非常有限。在国外,案主满意度评估被广泛用于社会服务相关领域,也发展了一系列相关的理论模式,尤其是发展出了许... 详细信息

中国社会工作近年来发展迅速,社会工作实务也随之蓬勃发展,然而目前对于社会工作服务评估却尚未形成体系,现有的评估方法也非常有限。在国外,案主满意度评估被广泛用于社会服务相关领域,也发展了一系列相关的理论模式,尤其是发展出了许多具有较高信度和效度保证的量表,并以此来促进社会服务质量的提高。但是案主满意度评估在我国社会工作实务中的应用还比较少见,因此笔者认为很有必要将案主满意度评估以及一些主要的量表进行介绍,希望能对我国的社会工作实务评估工作提供一定的参考和借鉴作用。

关键词：案主满意度社会工作实务评估社会工作

New approach to assess sperm DNA fragmentation dynamics： Fine-tuning mathematical models

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Journal of Animal Science and Biotechnology 2017年第3期8卷 592-600页

作者： Isabel Ortiz Jesus Dorado Jane Morrell Jaime Gosalvez Francisco Crespo Juan M.Jimenez Manuel Hidalgo Veterinary Reproduction Group Department of Animal Medicine and Surgery Faculty of Veterinary Medicine University of Cordoba 14071 Cordoba Spain Department of Clinical Sciences Division of Reproduction Swedish University of Agricultural Sciences Box 7054 SE-75007 Uppsala Sweden Department of Biology Universidad Aut6noma de Madrid 28049 Madrid Spain Department of Reproduction Centro Militar de Cria Caballar (FESCCR-Ministry of Defense) 05005 Avila Spain Department of Chemistry and Physics of Materials University of Salzburg Hellbrunner StraBe 34/111 A-5020 Salzburg Austria

Background： Sperm DNA fragmentation（sDF） has been proved to be an important parameter in order to predict in vitro the potential fertility of a semen sample. Colloid centrifugation could be a suitable technique to select those donkey sperm more resistant to DNA fragmentation after thawing. Previous studies have shown that to elucidate the latent damage of the DNA molecule, sDF should be assessed dynamically, where the rate of fragmentation between treatments indicates how resistant the DNA is to iatrogenic damage. The rate of fragmentation is calculated using the slope of a linear regression equation. However, it has not been studied if s DF dynamics fit this model. The objectives of this study were to evaluate the effect of different after-thawing centrifugation protocols on sperm DNA fragmentation and elucidate the most accurate mathematical model（linear regression, exponential or polynomial） for DNA fragmentation over time in frozen-thawed donkey ***： After submitting post-thaw semen samples to no centrifugation（UDC）, sperm washing（SW） or single layer centrifugation（SLC） protocols, sD F values after 6 h of incubation were significantly lower in SLC samples than in SW or *** of determination（R-2） values were significantly higher for a second order polynomial model than for linear or exponential. The highest values for acceleration of fragmentation（aSDF） were obtained for SW, fol owed by SLC and ***： SLC after thawing seems to preserve longer DNA longevity in comparison to UDC and SW. Moreover,the fine-tuning of models has shown that sDF dynamics in frozen-thawed donkey semen fit a second order polynomial model, which implies that fragmentation rate is not constant and fragmentation acceleration must be taken into account to elucidate hidden damage in the DNA molecule.

关键词： Colloid centrifugation Dynamics Fine-tuning Mathematical models Sperm DNA fragmentation

Brain Processing of Fearful Facial Expression in Mentally Disordered Offenders

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Journal of Behavioral and Brain Science 2011年第3期1卷 115-123页

作者： Katarina Howner Hakan Fischer Thomas Dierks Andrea Federspiel Lars-Olof Wahlund Tomas Jonsson Maria Kristoffersen Wiberg Marianne Kristiansson Department of Clinical Neuroscience Karolinska InstituteStockholmSweden NVS-Department Karolinska InstituteStockholmSweden Department of Psychology Stockholm UniversityStockholmSweden Department of Psychiatric Neurophysiology University Hospital for PsychiatryBernSwitzerland Department of Clinical Science Intervention and TechnologyKarolinska InstituteStockholmSweden

Emotional facial expressions are important cues for interaction between people. The aim of the present study was to investigate brain function when processing fearful facial expressions in offenders with two psychiatric disorders which include impaired emotional facial perception;autism spectrum disorder (ASD) and psychopathy (PSY). Fourteen offenders undergoing forensic psychiatric assessment (7 with ASD, and 7 psychopathic offenders) and 12 healthy controls (HC) viewed fearful and neutral faces while undergoing functional magnetic resonance imaging (fMRI). Brain activity (fearful versus neutral faces) was compared both between HC and offenders and between the two offender groups (PSY and ASD). Functional co-activation was also investigated. The offenders had increased activity bilaterally in amygdala and medial cingulate cortex as well as the left hippocampus during processing fearful facial expressions compared to HC. The two subgroups of offenders differed in five regions compared with each other. Results from functional co-activation analysis suggested a strong correlation between the amygdala and anterior cingulate cortex (ACC) in the left hemisphere only in the PSY group. These findings suggest enhanced neural processing of fearful faces in the amygdala as well as in other facial processing brain areas in offenders compared to HC. Moreover, the co-activation between amygdala and ACC in the PSY but not the ASD group suggested qualitative differences in amygdala activity in the two groups. Since the sample size is small the study should be regarded as a pilot study.

关键词： Psychopathy Autism Spectrum Disorder Offenders fMRI Emotional Facial Processing

壳聚糖金属配合物处理后竹材的防褐腐作用及力学性能(英文)

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林业科学 2007年第8期43卷 106-110页

作者：孙芳利段新芳毛胜凤吕建全王建辉浙江林学院工程学院中国林业科学研究院木材工业研究所北京100091

以4年生新伐毛竹为试材,以褐腐菌棉腐卧孔菌为试菌,对壳聚糖铜配合物(CCC)、壳聚糖锌配合物(CZC)及相应的金属盐(氯化锌)和铜铬硼(CCB)、ACQ处理材的耐腐性能、力学性能及胶接性能进行研究。结果表明:1)CCC处理的竹材对棉腐卧孔菌的耐... 详细信息

以4年生新伐毛竹为试材,以褐腐菌棉腐卧孔菌为试菌,对壳聚糖铜配合物(CCC)、壳聚糖锌配合物(CZC)及相应的金属盐(氯化锌)和铜铬硼(CCB)、ACQ处理材的耐腐性能、力学性能及胶接性能进行研究。结果表明:1)CCC处理的竹材对棉腐卧孔菌的耐腐性能不及CCB和ACQ处理材;但是,随着CCC处理浓度的增加,处理材耐褐腐性能明显增加,当处理材中金属离子保持量达到5.141kg.m-3时,腐朽后质量损失低于6.1%。2)CZC处理毛竹试材的耐腐效果低于CCC、CCB和ACQ,略高于氯化锌处理材,当CZC中金属离子保持量高于5.091kg.m-3时,处理材的质量损失在26.4%～29.0%之间。3)同素材(未处理材)相比,经防腐剂处理后的竹材力学性能及胶接性能均有不同程度下降,尤其是CCB处理材。在所测指标中,抗弯弹性模量和抗弯强度下降最明显,横纹抗压强度和胶接强度除CCB外变化不大。

关键词：竹材壳聚糖金属配合物耐腐性能力学强度胶接强度

Water quality and water-use conflicts in Lake Taabo(Ivory Coast)

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Open Journal of Ecology 2012年第1期2卷 38-47页

作者： Noel Groga Allassane Ouattara Sebastino Da Costa Alain Dauta Olivier Beauchard Jacques Moreau Germain Gourene Pascal Laffaille Laboratoire d’Ecologie et de Biologie Aquatique(LEBA)UFR des Sciences et de Gestion de l’Environnement Universite d’Abobo-Adjame AbidjanAbidjanFrance Universite de Toulouse ToulouseFrance Centre National de Recherche Agronomique(CNRA)Projet Challenge Programm BP AbidjanFrance CNRS UMR 5245 Laboratoire Ecologie Fonctionnelle et EnvironnementToulouseFrance Ecosystem Management Research Group-Universiteitsplein Department of BiologyCampus Drie EikenUniversity of AntwerpWilrijkBelgium Institut National Polytechique de Toulouse Universite Paul SabatierToulouseFrance Ecole Nationale Superieur Agronomique de Toulouse ToulouseFrance

The Lake Taabo (Ivory Coast, Africa) results of the construction of the Taabo dam on the Bandama River. The changes in the water level of the 69-km2 lake depend on 1) the rainfall linked to alternating dry/wet seasons;2) the extraction of water for human uses;3) the discharge of water from the upstream dam and the volumes turbined by the Kossou dam;4) the various anthropic effects (discharge of untreated waste water from towns and industries, and leaching from agricultural land). The average concentrations of nutrients (NH4-N: 1.1 mg/L, NO3-N: 1.62 mg/L, PO4-P: 10 mg/L, SiO2: 15 mg/L) and chlo- rophyll a (from 4.8 to 16.5 μg/L, average 11.4 μg/L) indicates some degree of eutrophication. The cumulated effects that threaten the ecosystem (degradation of water quality and eutrophication) are such that they are likely to interfere with various water uses. In a context of growing health and environmental concerns in Africa, this study demonstrates conflicts between different uses of this water resource and the urgent need for an appropriate policy including specific monitoring of lake water quality, wastewater control, and a programme to reduce agricultural fertilizers.

关键词： Conflicts over Water Use Pollution Tropical Lake Lake Structure

Improved cryopreservation of human hepatocytes using a new xeno free cryoprotectant solution

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World Journal of Hepatology 2012年第5期4卷 176-183页

作者： Mohammed Saliem Frida Holm Rosita Bergstrm Tengzelius Carl Jorns Lisa-Mari Nilsson Bo-Gran Ericzon Ewa Ellis Outi Hovatta Division of Obstetrics and Gynecology Department of Clinical ScienceIntervention and TechnologyKarolinska Institute141 86 StockholmSweden Division of Transplantation Surgery Department of Clinical ScienceIntervention and TechnologyKarolinska Institute141 86 StockholmSweden Division of Pediatrics Department of Clinical ScienceIntervention and TechnologyKarolinska Institute141 86 StockholmSweden

AIM:To optimize a xeno-free cryopreservation protocol for primary human ***:The demand for cryopreserved hepatocytes is increasing for both clinical and research *** several hepatocyte cryopreservation protocols being available,improvements are urgently *** first compared controlled rate freezing to polystyrene box freezing and did not find any significant change between the *** the polystyrene box freezing,we compared two xeno-free freezing solutions for freezing of primary human hepatocytes:a new medium(STEM-CELLBANKER,CB),which contains dimethylsulphoxide(DMSO) and anhydrous dextrose,both permeating and non-permeating cryoprotectants,and the frequently used DMSO-University of Wisconsin(DMSOUW) *** viability of the hepatocytes was assessed by the trypan blue exclusion method as well as a calcein-esterase based live-dead assay before and after *** function of the hepatocytes was evaluated before and after cryopreservation by assessing enzymatic activity of 6 major cytochrome P450 isoforms(CYPs):CYP1A2,CYP2C9,CYP2C19,CYP2D6,CYP3A4 and ***:The new cryoprotectant combination preserved hepatocyte viability significantly better than the standard DMSO-UW protocol(P < 0.01).There was no significant difference in viability estimation between both the trypan blue(TB) and the Live-Dead Assay *** was a correlation between viability of fresh hepatocytes and the difference in cell viability between CB and DMSO protocols(r 2 = 0.69) using the TB ***,due to high within-group variability in the activities of the major CYPs,any statistical between-group differences were *** of human hepatocytes using the cryoprotectant combination was a simple and xeno-free procedure yielding better hepatocyte ***,it may be a better alternative to the standard DMSO-UW *** CYP activities did not seem to be a relevant way to compare hepatocyte function

关键词： Human hepatocytes Viability Cytochrome P540 Dimethylsulphoxide Cryoprotectant Cryopreservation

Patterns of Changes to Woody Vegetation near Resettlement Sites in Semi-arid Northwestern Ethiopia

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Journal of Resources and Ecology 2018年第3期9卷 317-329页

作者： Mulubrhan Balehegn Kidane Hintsa Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China International Ecosystem Management Partnership United Nations Environment Programme Beijing 100101 China Department of Animal Rangeland and Wildlife Sciences Mekelle University Mekelle Post Box 231 Ethiopia

Communal rangelands provide diverse ecosystem services to millions of pastoralists and agro-pastoralists. Resettling destitute communities into hitherto uninhabited communal rangelands and forests, a common practice throughout Sub-Saharan Africa, is a threat to the sustainable use of range and forest land resources. In order to understand the effect of resettlement on a semi-arid woodland in northwestern Ethiopia, satellite imagery of 23 resettlement villages taken over a period of fourteen years, and woody vegetation floristic data for three old resettlements, three new resettlements, two refugee camps and one protected area were analyzed using ANOVA and canonical correspondence analysis（CCA）. The normalized differential vegetation index（NDVI） and canopy cover around all village types decreased with disturbance gradients, while the magnitude of change varied according to the type of settlement. Limited canopy cover was observed in refugee camps and new resettlements, compared to old resettlements and protected areas. Woody vegetation height class showed a J shaped distribution in all sites except refugee camps（RC）, indicating a decline in vegetation. CCA showed that variables like site type, altitude and disturbance gradient significantly affected the diversity of woody species at the different sites. Comparison of individual species responses to disturbances indicated that low fodder value invaders like Dichrostachys cinerea, and many Acacia species were increasing in proportion and coverage at the expense of some multipurpose species including Tamarindus indica, Diospyros mespiliformis, and Pterocarpus lucens. In the absence of regulated vegetation use, resettlements result in a decline in overall vegetation cover and a shift in floristic diversity in favor of invasive species.

关键词： resettlement woody vegetation CCA woodland rangelands NDVl Ethiopia

Levels and trends of poly-and perfluoroalkyl substances in the Arctic environment-An update

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Emerging Contaminants 2019年第1期5卷 240-271页

作者： Derek Muir Rossana Bossi Pernilla Carlsson Marlene Evans Amila De Silva Crispin Halsall Cassandra Rauert Dorte Herzke Hayley Hung Robert Letcher Frank Riget Anna Roos Aquatic Contaminants Research Division Environment and Climate Change CanadaBurlingtonONCanada Department of Environmental Science Aarhus UniversityRoskildeDenmark Norwegian Institute for Water Research Fram CentreTromsøNorway Water Hydrology Ecology Division Environment and Climate Change CanadaSaskatoonSKCanada Lancaster Environment Centre Lancaster UniversityLancasterUnited Kingdom Air Quality Processes Research Section Environment and Climate Change CanadaTorontoONCanada Norwegian Institute for Air Research Fram CentreTromsøNorway Ecotoxicology and Wildlife Health Division Environment and Climate Change CanadaNational Wildlife Research CentreCarleton UniversityOttawaONCanada Department of Bioscience Aarhus UniversityRoskildeDenmark Greenland Institute of Natural Resources NuukGreenland Swedish Museum of Natural History StockholmSweden

Poly-and perfluoroalkyl substances(PFASs)are important environmental contaminants globally and in the early 2000s they were shown to be ubiquitous contaminants in Arctic *** reviews by Butt et *** Letcher et *** covered studies on levels and trends of PFASs in the Arctic that were available to *** purpose of this review is to focus on more recent work,generally published between 2009 and 2018,with emphasis on PFASs of emerging concern such as perfluoroalkyl carboxylates(PFCAs)and short-chain perfluoroalkyl sulfonates(PFSAs)and their *** measurements over the period 2006e2014 have shown that fluorotelomer alcohols(FTOHs)as well as perfluorobutanoic acid(PFBA)and perfluoroctanoic acid(PFOA)are the most prominent PFASs in the arctic atmosphere,all with increasing concentrations at Alert although PFOA concentrations declined at the Zeppelin Station(Svalbard).Results from ice cores show generally increasing deposition of PFCAs on the Devon Ice cap in the Canadian arctic while declining fluxes were found in a glacier on *** extensive dataset exists for long-term trends of long-chain PFCAs that have been reported in Arctic biota with some datasets including archived samples from the 1970s and *** in PFCAs over time vary among the same species across the North American Arctic,East and West Greenland,and *** long term time series show a decline from higher concentrations in the early *** there have been recent(post 2010)increasing trends of PFCAs in ringed seals in the Canadian Arctic,East Greenland polar bears and in arctic foxes in *** biological sampling is helping to determine these relatively short term *** levels of some PFCAs have been explained by continued emissions of long-chain PFCAs and/or their precursors and inflows to the Arctic Ocean,especially from the North *** the effectiveness of biological sampling for temporal trends in long-chain PFCAs an

关键词： Perfluoroalkyl substances PFASs Perfluoroalkyl carboxylates Perfluoroalkyl sulfonates Perfluorobutanoic acid Perfluorooctanoic acid Air Seawater Ice caps Biota Contaminants Long-range transport Review