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A comparison of zooplankton assemblages in Nansi Lake and Hongze Lake,potential influences of the East Route of the South-to-North Water Transfer Project,China

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Journal of Oceanology and Limnology 2021年第2期39卷 623-636页

作者： Kandathil Radhakrishnan DIVYA Shasha ZHAO Yushun CHEN Fei CHENG Lei ZHANG Jiao QIN Thundiparambil Sathrajith ARUNJITH V.bjorn SCHMIDT Songguang XIE Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China Key Laboratory of Sustainable Fisheries and Environmental Protection for Lakes of Northern Jiangsu Huai’an Research CenterInstitute of HydrobiologyChinese Academy of SciencesHuai’an 223002China

Nansi Lake and Hongze Lake are both water storage lakes along the East Route of the South-to-North Water Transfer project(ESNT).Frequent changes in hydrologic properties are responsible factors for controlling the zooplankton community assemblages in both lakes,so we studied the possible influence of water transfer and environmental factors on zooplankton community structure and *** assemblages were investigated seasonally for one year in both lakes;a total of 133 and 122 zooplankton taxa were identified in Nansi Lake and Hongze Lake,*** most dominant rotifer species were littoral,e.g.,Keratella tecta,Keratella valga and Lecane lunaris in Nansi Lake and Brachionus angularis,Brachionus forficula and Polyarthra vulgaris in Hongze ***,Nansi Lake had a higher Shannon-Wiener diversity index value(5.13),while Hongze Lake had a higher species richness index(4.21).The average number of zooplankton across seasons in Nansi Lake(protozoa:774±63 ind./L,rotifers:4817±212 ind./L,cladocerans:896±14 ind./L,copepod:435±42 ind./L)was comparatively lower than Hongze Lake(protozoa:1238±63 ind./L,rotifers:6576±112 ind./L,cladocerans:1013±20 ind./L,copepod:534±25 ind./L).Canonical correspondence analysis identified differing environmental gradients that were most responsible for influencing zooplankton communities in the two lakes(Hongze Lake:NH4-N,total nitrogen,transparency and pH;Nansi:pH,temperature and total phosphorus).Frequent changes related to water transfer in lakes favoured the diversity of rotifers and protozoa *** habitat preference,changes in community structure and opportunistic peaks and extinction of certain taxa were also observed in the study lakes.

关键词： zooplankton assemblage water transfer Hongze Lake Nansi Lake

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The effect of electrochemically inactive Ti substituted for Ru in Li_(2)Ru_(1-x)Ti_xO_(3) on structure and electrochemical performance

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Journal of Energy Chemistry 2021年第9期30卷 222-228页

作者： Ye Yao Lu Zhang Florian Sigel bjorn Schwarz Helmut Ehrenberg Gang Chen Fei Du Chunzhong Wang Changchun Normal University Changchun 130031China Key Laboratory of Physics and Technology for Advanced Batteries(Ministry of Education) State Key Laboratory of Superhard MaterialsCollege of PhysicsJilin UniversityChangchun 130012China Institute for Applied Materials(IAM) Karlsruhe Institute of Technology(KIT)76344 Eggenstein-LeopoldshafenGermany

The approach of substituting electrochemically active with inactive elements has widely been used to improve the electrochemical performance of Li-rich intercalation cathode materials. This especially is true for Li-rich compounds where almost all of the Li+ions are reversibly(de)intercalated during electrochemical cycling. The beneficial mechanism behind this substitution with electrochemically inactive elements is still not clear yet. Li_(2)RuO_(3) is chosen as basis for a model solid solution system to investigate the effect of electrochemically inactive elements owing to its high specific capacity of more than 300 m Ah g^(-1) and the significant contribution of anion redox mechanism. Herein, Li_(2)Ru_(1-x)Ti_xO_(3) solid solution series are synthesized and the effect of substituting with electrochemical inactive Ti for Ru on structure and electrochemical performance have been comprehensively investigated. The electrochemical performance is significantly improved, especially for Li_(2)Ru_(0.8)Ti_(0.2)O_(3), and the capacity retention after 50 cycles increases from 81% to 90%, as compared to the end member Li_(2)RuO_(3). Results of electrochemical impedance spectroscopy show that Ti substitution reduces the charge transfer impedance, which favors the Li+diffusion across the electrolyte–electrode interface and improves the electronic conductivity. For the first time,nuclear magnetic resonance was utilized to confirm that a small part of Ti ions exchange their position with Li ions in the Li layer. This research provides a better understanding of electrochemical inactive element substitution and strong insights for the functional design of the next generation of Li-rich cathode materials.

关键词： Li_(2)Ru_(1-x)Ti_xO_(3) Lithium ion batteries Inactive element substitution XRD NMR

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F?(H2O)+CH3I Ligand Exchange Reaction Dynamics

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Chinese Journal of Chemical Physics 2020年第2期33卷 210-216,I0003,I0039-I0040页

作者： bjorn Bastian Tim Michaelsen Milan Oncák Jennifer Meyer Roland Wester Institut für Ionenphysik und Angewandte Physik Universitat InnsbruckTechnikerstraβe 256020 InnsbruckAustria

Single hydration of the gas phase F^-+CH3I→CH3F reaction allows to probe solvent effects on a fundamental nucleophilic substitution *** the same time,the addition of a solvent molecule opens alternative product ***,we present crossed beam imaging results on the dynamics of the F^-(H2O)+CH3I→[FCH3I]^-+H2O ligand exchange pathway at collision energies between 0.3 and 2.6 *** kinetic energies are constrained by the stability requirement of the weakly bound product *** implies substantial internal excitation of the water molecule and disfavors effcient energy redistribution in an intermediate complex,which is reflected by the suppression of low kinetic energies as collision energy *** 0.3 eV,internal nucleophilic displacement is important and is discussed in light of the competing nucleophilic substitution pathways that form I^- and I^-(H2O).

关键词： Reaction dynamics Ligand exchange Microsolvation Crossed beams Velocity map imaging

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Concealed Integrity Monitoring for Wireless Sensor Networks

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Wireless Sensor Network 2011年第1期3卷 10-17页

作者： bjorn Stelte Thomas Bühring Institut für Technische Informatik Universitat der Bundeswehr MünchenNeubibergGermany

Nowadays, sensor networks are widely installed around the world. Typical sensors provide data for healthcare, energy management, environmental monitoring, etc. In the future sensors will become a part of critical infrastructures. In such a scenario the network operator has to monitor the integrity of the network devices, otherwise the trustworthiness of the whole system is questionable. The problem is that every integrity protocol needs a secure channel between the devices. Therefore, we will introduce a covert channel for hidden transportation of integrity monitoring messages. The covert channel enables us to hide integrity check messages embedded into regular traffic without giving potential attackers a hint on the used integrity protocol.

关键词： Covert Channel Integrity Monitoring Wireless Sensor Network

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Parkinson’s disease and translational research

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Translational Neurodegeneration 2020年第4期9卷 547-557页

作者： Elisabeth Dinter Theodora Saridaki Leonie Diederichs Heinz Reichmann bjorn H.Falkenburger Department of Neurology Technische Universitat DresdenDresdenGermany Deutsches Zentrum fur Neurodegenerative Erkrankungen DresdenGermany Department of Neurology RWTH University AachenAachenGermany

Parkinson's disease(PD)is diagnosed when patients exhibit bradykinesia with tremor and/or rigidity,and when these symptoms respond to dopaminergic *** in the last years there was a greater recognition of additional aspects of the disease including non-motor symptoms and prodromal states with associated pathology in various regions of the nervous *** this review we discuss current concepts of two major alterations found during the course of the disease:cytoplasmic aggregates of the protein a-synuclein and the degeneration of dopaminergic *** provide an overview of new approaches in this field based on current concepts and latest *** many areas,translational research on PD has advanced the understanding of the disease but there is still a need for more effective therapeutic options based on the insights into the basic biological phenomena.

关键词： α-Synuclein Pre-formed fibrils Protein aggregates Aggresome Dopamine deficiency Medium spiny neurons Autophagy

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地震反射振幅

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国外油气勘探 1993年第5期 557-567页

作者： bjorn Ursin 蒋录全

随炮检距变化而变化的地震反射振幅包含着弹性参数信息。在叠前振幅分析中,试图通过反射系数随入射角变化的函数关系来提取这些信息。一般采用的反射系数的近似公式,常常忽略随炮检距变化而变化的几何扩散和非弹性衰减因素。用入射角作... 详细信息

随炮检距变化而变化的地震反射振幅包含着弹性参数信息。在叠前振幅分析中,试图通过反射系数随入射角变化的函数关系来提取这些信息。一般采用的反射系数的近似公式,常常忽略随炮检距变化而变化的几何扩散和非弹性衰减因素。用入射角作应变量计算上是无效的,因为地震资料是作为炮检距的函数记录的。对弹性波反射系数、透射系数、几何扩散及复旅行时(包括非弹性衰减)推导出了改进的近似公式。对于一维介质,综合利用这些近似公式获得了以炮检距坐标的泰勒级数表示的地震反射(P 波、S 波或转换波)振幅表达式。泰勒级数的系数直接由介质参数求得,而不用射线参数。对于一次反射 P 波,用动态射线追踪来计算随炮检距变化而变化的透射系数、反射系数、几何扩散和非弹性衰减。结果表明透射系数随炮检距的变化较小,而几何扩散、吸收系数及反射系数的变化则相当明显。新的近似公式已用于地震模拟而不需用射线追踪。振幅用炮检距的4阶多项式近似,旅行时用常规的平方根公式近似,用同样公式表示吸收因子,该近似模拟与动态射线追踪相比,对零炮检距两者相同,对炮检距小于反射深度的情况二者的结果非常接近。

关键词：地震反射振幅弹性模数反射系数透射系数泰勒展开

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Optical diagnosis of colorectal polyps using high-definition i-scan: An educational experience

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World Journal of Gastroenterology 2013年第27期19卷 4334-4343页

作者： Mariёlle WE Bouwens Rogier de Ridder Ad AM Masclee Ann Driessen Robert G Riedl bjorn Winkens Silvia Sanduleanu Division of Gastroenterology and Hepatology Department of Internal MedicineMaastricht University Medical Center NUTRIM School for NutritionToxicology and MetabolismMaastricht University Medical Center Department of Pathology Maastricht University Medical Center Department of Methodology and Statistics Maastricht University Medical Center GROW School for Oncology and Developmental BiologyMaastricht University Medical Center

AIM:To examine performances regarding prediction of polyp histology using high-definition (HD) i-scan in a group of endoscopists with varying levels of experience. METHODS:We used a digital library of HD i-scan still images, comprising twin pictures (surface enhancement and tone enhancement), collected at our university hospital. We defined endoscopic features of adenomatous and non-adenomatous polyps, according to the following parameters:color, surface pattern and vascular pattern. We familiarized the participating endoscopists on optical diagnosis of colorectal polyps using a 20-min didactic training session. All endoscopists were asked to evaluate an image set of 50 colorectal polyps with regard to polyp histology. We classified the diagnoses into high confidence (i.e., cases in which the endoscopist could assign a diagnosis with certainty) and low confidence diagnoses (i.e., cases in which the endoscopist preferred to send the polyp for formal histology). Mean sensitivity, specificity and accuracy per endoscopist/image were computed and differences between groups tested using independent-samples t tests. High vs low confidence diagnoses were compared using the pairedsamples t test. RESULTS:Eleven endoscopists without previous experience on optical diagnosis evaluated a total of 550 images (396 adenomatous, 154 non-adenomatous). Mean sensitivity, specificity and accuracy for diagnosing adenomas were 79.3%, 85.7% and 81.1%, respectively. No significant differences were found between gastroenterologists and trainees regarding performances of optical diagnosis (mean accuracy 78.0%vs 82.9%,P = 0.098). Diminutive lesions were predicted with a lower mean accuracy as compared to non-diminutive lesions (74.2% vs 93.1%, P = 0.008). A total of 446 (81.1%) diagnoses were made with high confidence. High confidence diagnoses corresponded to a significantly higher mean accuracy than low confidence diagnoses (84.0% vs 64.3%, P = 0.008). A total of 319 (58.0%) images were evalu

关键词： Colonoscopy High-definition i-scan Optical diagnosis Colorectal polyps Training

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Hidden Patterns behind Doping Use among Norwegians 18-19 Years Old

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Journal of Sports Science 2013年第1期1卷 26-36页

作者： Jan Ove Tangen bjorn Barland Department of Sport and Outdoor Life Studies Telemark University College Bo i Telemark 3800 Norway Norwegian Police University College Slemdalsveien 5 0369 Oslo Norway

There is a growing public concern about the increasing use of performance enhancing drugs （doping） in sport, exercise and fitness activities. Research has been carried out to answer the question ＂Why do exercising young people use performance enhancing drugs？＂ The explanations of most quantitative researches are based on bivariate statistical analysis. But there are reasons to believe that one factor or motive is not suffice to explain such a complex and stigmatized behaviour. More probably, there may be clusters of psychological and societal, more or less hidden, reasons behind such behaviour. This study uses EFA （exploratory factor analysis） and combines sets of variables, in order to reveal hidden factors or patterns in the empirical data. Our study indicates that this kind of doping use should be interpreted within a social context where youths struggle with their lives, making sense of societal demands and expectations, using the ＂tools＂ they find fitting, and make their choices meaningful and functional. In other words, doping has something to do with muscles, self-presentation and meaning trying to build identities in a world where the body is the main symbol of value and morality.

关键词： Performance enhancing drugs youth exercise identity self-presentation meaning.

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A review of ecological impacts of global climate change on persistent organic pollutant and mercury pathways and exposures in arctic marine ecosystems

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Current Zoology 2015年第4期61卷 617-628页

作者： Melissa A. MCKINNEY Sara PEDRO Rune DIETZ Christian SONNE Aaron T. FISK Denis ROY bjorn M. JENSSEN Robert J. LETCHER Department of Natural Resources and the Environment University of Connecticut Storrs CT 06269 USA Center for Environmental Sciences and Engineering University of Connecticut Storrs CT 06269 USA Department of Bioscience Arctic Research Centre Aarhus University Roskilde DK-4000 Denmark Great Lakes Institute for Environmental Research University of Windsor Windsor ON N9B 3P4 Canada Department of Biology Norwegian University of Science and Technology Trondheim NO-7491 Norway Wildlife and Landscape Science Directorate Science and Technology Branch Environment Canada National Wildlife Research Centre Carleton University Ottawa ON K1A 0H3 Canada

Bioaccumulative and biomagnifying contaminants, such as persistent organic pollutants （POPs） and mercury （Hg）, have for decades been recognized as a health concern in arctic marine biota. In recent years, global climate change （GCC） and related loss of arctic sea ice have been observed to be driving substantial change in arctic ecosystems. This review summarizes findings documenting empirical links between GCC-induced ecological changes and alterations in POP and Hg exposures and pathways in arctic marine ecosystems. Most of the studies have reported changes in POP or Hg concentrations in tissue in relation to GCC-induced changes in species trophic interactions. These studies have typically focused on the role of changes in abun- dance, habitat range or accessibility of prey species, particularly in relation to sea ice changes. Yet, the ecological change that re- suited in contaminant trend changes has often been unclear or assumed. Other studies have successfully used chemical tracers, such as stable nitrogen and carbon isotope ratios and fatty acid signatures to link such ecological changes to contaminant level variations or trends. Lower sea ice linked-diet changes/variation were associated with higher contaminant levels in some popula- tions of polar bears, ringed seals, and thick-billed murres, but the influence of changing trophic interactions on POP levels and trends varied widely in both magnitude and direction. We suggest that future research in this new area of GCC-linked ecotox- icology should focus on routine analysis of ancillary ecological metrics with POP and Hg studies, simultaneous consideration of the multiple mechanisms by which GCC and contaminant interactions can occur, and targeted research on changing exposures and toxicological effects in species known to be sensitive to both GCC and contaminants [Current Zoology 61 （4）： 617-628, 2015].

关键词： Climate change Ecological change Contaminants Trends Arctic Marine ecosystems

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Coconut Press Cake Alkaline Extract—Protein Solubility and Emulsification Properties

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Food and Nutrition Sciences 2013年第9期4卷 29-37页

作者： Borges Chambal bjorn Bergenstahl Petr Dejmek Department of Chemical Engineering Faculty of EngineeringEduardo Mondlane UniversityMaputoMozambique Department of Food Technology Engineering and Nutrition Lund UniversityLundSweden

The solubility and the emulsification properties of a crude freeze dried alkaline protein extract (APE), 30% protein, obtained from coconut milk press cake by one step extraction at pH 11, were characterized at pH 2 to 11, and the cream and subnatant fractions of the emulsion studied by SDS-PAGE electrophoresis. The protein solubility followed U profile, showing a minimum at pH 3 to 4, close to but not identical to reported iso-electric points of 4 - 5 for many coconut protein fractions. The extract showed good capacity to form oil-in-water emulsion outside the low solubility pH range. The bands that appeared to play a role in the emulsification were found at 32 and 42 kDa in SDS-PAGE electrophoresis, but the most predominant absorbed band was at 23 kDa.

关键词： Coconut Proteins Coconut Milk Press Cake Alkaline Extraction Oil-in-Water Emulsions Solubility SDS-PAGE Electrophoresis

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