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地震地质 2000年第B12期22卷 63-78页

作者：李红春顾德隆 Dorte Paulsen 王非陈文寄尹功明程海 r.L.edwards 美国南加州大学地球科学系 ca900890740 中国地震局地质研究所北京100029 美国明尼苏达大学地质和地球物理系 mn55344

采自陕西省柞水县的石笋给出了过去 750a来的高分辨率气候记录以及全新世和80～ 330ka之间的低分辨率的气候变化。定年方法使用了石笋生长纹层计数法、2 10 Pb法和TIMS2 30 Th法。分析了石笋中δ18O和δ13C的气候含义 ,认为当δ18O和δ... 详细信息

采自陕西省柞水县的石笋给出了过去 750a来的高分辨率气候记录以及全新世和80～ 330ka之间的低分辨率的气候变化。定年方法使用了石笋生长纹层计数法、2 10 Pb法和TIMS2 30 Th法。分析了石笋中δ18O和δ13C的气候含义 ,认为当δ18O和δ13C值变重时 ,指示干热的气候组合 ,当δ18O和δ13C值同时变轻时 ,指示湿冷的气候组合。在长时间尺度δ18O值的变化以反映温度变化为主 ,δ13C值的变化反映湿度变化为主。当δ18O变轻 ,而δ13C变重时 ,指示干冷气候。这时期的夏季风很弱而冬季风很强 ,相反 ,当δ18O变重 ,而δ13C变轻时 ,指示湿热气候 ,表明夏季风很强 ,冬季风很弱。过去 750a的记录中分为 :公元 12 50～ 152 0年的温暖中世纪 (MedievalWarmPeriod) ,公元 152 0～ 182 0年的湿冷小冰期 (LittleIceAge)和公元 182 0年以来的温热期。全新世的气候在 4 0 0 0a左右有一显著的变化。在此时之前的温度低于全新世的平均气温 ,而在此之后的温度高于全新世的平均气温。全新世气候记录可细分为 18个不同的时期。

关键词： δ^18O 全新世 δ^13C 石笋冬季风古季风夏季风柞水县记录陕南

New insights into sodium transport regulation in the distal nephron:role of G-protein coupled receptors

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World Journal of Biological Chemistry 2016年第1期7卷 44-63页

作者： Luciana Morla Aurélie edwards Gilles Crambert Sorbonne Universités UPMC Univ Paris 06INSERMUniversité Paris DescartesSorbonne Paris CitéUMR_S 1138Centre de Recher-che des Cordeliers CNrS ErL 8228 Centre de Recherche des CordeliersLaboratoire de Métabolisme et Physiologie Rénale Centre de recherche des Cordeliers INSERM U1138CNRS ERL 8228Equipe 3:Métabolisme et Physiologie Rénale

The renal handling of Na^+ balance is a major determinant of the blood pressure(BP) level. The inability of the kidney to excrete the daily load of Na+ represents the primary cause of chronic hypertension. Among the different segments that constitute the nephron, those present in the distal part(i.e., the cortical thick ascending limb, the distal convoluted tubule, the connecting and collecting tubules) play a central role in the fine-tuning of renal Na^+ excretion and are the target of many different regulatory processes that modulate Na^+ retention more or less efficiently. G-protein coupled receptors(GPCrs) are crucially involved in this regulation and could represent efficient pharmacological targets to control BP levels. In this review, we describe both classical and novel GPCr-dependent regulatory systems that have been shown to modulate renal Na^+ absorption in the distal nephron. In addition to the multiplicity of the GPCr that regulate Na^+ excretion, this review also highlights the complexity of these different pathways, and the connections between them.

关键词： Kidney Sodium excretion Blood pressure G-protein coupled receptors Peptide hormone

Tracking domestic ducks:A novel approach for documenting poultry market chains in the context of avian influenza transmission

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Journal of Integrative Agriculture 2016年第7期15卷 1584-1594页

作者： Chang-Yong Choi John Y Takekawa XIONG Yue LIU Ying Martin Wikelski George Heine Diann J Prosser Scott H Newman John edwards Fusheng Guo Xiangming Xiao Department of Microbiology and Plant Biology Center for Spatial AnalysisUniversity of OklahomaNormanOK 73019USA Western Ecological research Center U.S.Geological SurveyVallejoCA 94592USA National Audubon Society San FranciscoCA 94104USA Key Laboratory of Poyang Lake Wetland and Watershed research Jiangxi Normal UniversityNanchang 330022P.R.China Department of Migration and Immuno-Ecology Max Planck Institute for OrnithologyRadolfzell D-78315Germany Department of Biology University of KonstanzKonstanz D-78457Germany Patuxent Wildlife research Center U.S.Geological SurveyBeltsvilleMD 20705USA Emergency Center for Transboundary Animal Diseases(ECTAD)Vietnam Office Food and Agriculture Organization of the United NationsHanoi 10000Vietnam Emergency Center for Transboundary Animal Diseases(ECTAD)China Office Food and Agriculture Organization of the United NationsBeijing 100600P.R.China Murdoch University MurdochWA 6150Australia Institute of Biodiversity Sciences Fudan UniversityShanghai 200433P.R.China

Agro-ecological conditions associated with the spread and persistence of highly pathogenic avian inlfuenza （HPAI） are not well understood, but the trade of live poultry is suspected to be a major pathway. Although market chains of live bird trade have been studied through indirect means including interviews and questionnaires, direct methods have not been used to identify movements of individual poultry. To bridge the knowledge gap on quantitative movement and transportation of poultry, we introduced a novel approach for applying telemetry to document domestic duck movements from source farms at Poyang Lake, China. We deployed recently developed transmitters that record Global Positioning System （GPS） locations and send them through the Groupe Spécial Mobile （GSM） cellular telephone system. For the ifrst time, we were able to track individually marked ducks from 3 to 396 km from their origin to other farms, distribution facilities, or live bird markets. Our proof of concept test showed that the use of GPS-GSM transmitters may provide di-rect, quantitative information to document the movement of poultry and reveal their market chains. Our ifndings provide an initial indication of the complexity of source-market network connectivity and highlight the great potential for future telemetry studies in poultry network analyses.

关键词： avian inlfuenza domestic duck market chain network poultry telemetry

Change patterns of oncomelanid snail burden in areas within the Yangtze river drainage after the three gorges dam operated

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Infectious Diseases of Poverty 2019年第3期8卷 64-71页

作者： Si-Min Dai Jeffrey edwards Zhou Guan Shan Lv Shi-Zhu Li Li-Juan Zhang Jun Feng Ning Feng Xiao-Nong Zhou Jing Xu National Institute of Parasitic Diseases Control and Prevention Chinese Center for Disease Control and Prevention207 Ruijin Er RoadShanghai 200025China Key Laboratory of Parasite and Vector Biology Ministry of HealthWHO Collaborating Centre for Tropical DiseasesNational Tropical Disease Research Center207 Ruijin Er RoadShanghai 200025China Department of Global Health University of WashingtonSeattleWashingtonUSA Center for Global Public Health Chinese Center for Disease Control and PreventionRoom 211155 Changbai RoadChangping DistrictBeijing 102206China Center of Disease Control and Prevention of Henan Province 105 Nongyenan RoadZhengzhou 450016HenanChina

Background:An"integrated control"strategy has been implemented within seven provinces at highest risk for schistosomiasis along Yangtze river in Peoples'republic of China(***)since *** O ncom elania hupensis is the only intermediate host of the blood fluke(Schistosom a japonicum),controlling the distribution of snails is considered an essential and effeaive way to reduce the risk of schistosomiasis *** study aimed to determine the snail area burden and annual trend among provinces with potential risk for schistosomiasis along the Yangtze river,above and below the Three Gorges Dam(TGD).Methods:This retrospective study utilized data previously collected from the National Parasitic Diseases Control Information Management System(NPDCIMS)on annual snail surveys from 2009 to *** statistics were performed for analyzing the snail burden by provinces,counties,type of environmental location and year,and mapping was conducted to present the snails ***:From 2009 to 2017,the total snail infested area decreased by 4.22%,from 372253 hm^2 to 356553 hm^2 within the seven high risk *** majority of snails were found in the marshland and lake regions,outside of control *** total snail burden trend remained relatively stable in upstream regions above the TGD from 2010 to 2015,while the trend decreased within downstream regions during this *** 2016 and 2017,the total snail burden trend increased in both upstream and downstream provinces,however,upstream saw a larger *** 2009 to 2017,there were a total of 5990 hm^2 of newly developed snail areas in the seven study provinces and the majority were concentrated in regions below the TGD,accounting for 5610 hm^2(93.70%).Conclusions:There has been a decline in total snail counts from 2009 to ***,new snail breeding areas were formed mainly within provinces downstream the TGD due to spread of snails,indicated that the oncomelanid snail would be d

关键词： Schistosomiasis Oncom elania hupensis Yangtze river Three gorges dam China Operational research

Plasticity Enhancement Processes in NiAl and MoSi_2

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Journal of Materials Science & Technology 1993年第6期9卷 405-415页

作者： r.Gibala H.Chang C.M.Czarnik K.M.edwards A.Misra Department of Materials Science and Engineering,University of Michigan,Ann Arbor,Michigan 48109-2136,USA

This paper demonstrates that plasticity enhancement processes previously observed in bcc metals and associated with the presence of surface films and precipitates or dispersoids are operative in or- dered intermetallic compounds.' Some specific results are given for NiAl-and MoSi_2-based *** plasticity of NiAl and related B2 ordered alloys at room temperature during monotonic deformation can be enhanced by application of surface films such as electroless nickel ***- nificant effects are also observed during cyclic *** presence of ductile second phases such as fcc γ or the ordered phase γ' introduced by alloying also enhances the plasticity of NiAl. MoSi_2 exhibits similar effects of surface films and second phases,but primarily at elevated tempera- tures,T>900℃.In this paper,we illustrate the effects of ZrO_2 surface films deposited near room temperature and TiC particulate additions introduced by powder processing *** all cases, the plasticity enhancement is associated with enhanced dislocation generation processes under the conditions of constrained deformation at the film-substrate or precipitate/dispersoid-matrix inter- face of the composite system.

关键词： plasticity ordered intermetallics NiAl MoSi_2

洞穴碳酸盐230Th-234U-238U测年初始钍校正的等时线研究

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洞穴碳酸盐230Th-234U-238U测年初始钍校正的等时线研究

蛇纹岩(纤蛇纹石和蛇纹石)矿泥覆盖对镍黄铁矿浮选的影响

高分辨记录与同位素技术在环境变化研究中的应用全国学术讨...

作者：蔡演军 Hai Cheng 安芷生 r.Laurence edwards 王先锋 Shen Chuan-Chou 中国科学院地球环境研究所黄土与第四纪地质国家重点实验室 Department ofGeology and Geophysics University of MinnesotaMN 55455 USA 中国科学院地球环境研究所黄土与第四纪地质国家重点实验室 Department ofGeology and Geophysics University of MinnesotaMN 55455 USA Department ofGeology and Geophysics University of MinnesotaMN 55455 USA Department ofGeosciences National Taiwan University Taipei 106TaiwanChina

＜正＞初始钍的校正是不纯沉积碳酸盐230Th-234U-238U测年的一个重要方面,洞穴石笋初始Th校正通常采用230Th/232Th的原子比值为4.4±2.2×10-6。多年来四种不同的等时线方法应用到不纯碳酸盐测年初始Th的校正中,其中全样品的等时线方...

＜正＞初始钍的校正是不纯沉积碳酸盐230Th-234U-238U测年的一个重要方面,洞穴石笋初始Th校正通常采用230Th/232Th的原子比值为4.4±2.2×10-6。多年来四种不同的等时线方法应用到不纯碳酸盐测年初始Th的校正中,其中全样品的等时线方法是目前公认的较为完善一种方法。本文通过测定云南同一石笋两个不同层位的9个样品的U、Th同位素组成,并进行等

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国外金属矿选矿 1982年第1期 12-17页

作者： C. r. edwards 孙籍

硫化镍矿石的选别,常常受脉石中所含蛇纹岩矿物的干扰。研究了蛇纹岩矿物如纤蛇纹石和蛇纹石矿泥的覆盖对未被氧化的镍黄铁矿浮选影响。此外,还曾使用在pH9时以戊基黄原酸钾为捕收剂的微型浮选试验、电泳和电子显微镜扫描。发现矿泥覆... 详细信息

硫化镍矿石的选别,常常受脉石中所含蛇纹岩矿物的干扰。研究了蛇纹岩矿物如纤蛇纹石和蛇纹石矿泥的覆盖对未被氧化的镍黄铁矿浮选影响。此外,还曾使用在pH9时以戊基黄原酸钾为捕收剂的微型浮选试验、电泳和电子显微镜扫描。发现矿泥覆盖层的形成与矿泥和硫化矿表面电荷有直接关系。添加改变矿泥表面电荷的化学药剂,如羧基甲基纤维素、糊精、焦磷酸盐和水玻璃,可有效地减少矿泥对镍黄铁矿浮选的有害影响。

关键词：纤蛇纹石镍黄铁矿石棉蛇纹岩变质岩矿泥

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利用海底瞬时双偶极法评价海洋气水合物资源

天然气地球科学 1998年第3期9卷 66-76页

作者： r.Nigel edwards 马建霞加拿大

甲烷水合物是水和甲烷气体形成的非化学计量的固态化合物,广布于世界范围的海底沉积物中,估计总储量超过10^(16)kg。每一体积水合物可产生164倍体积的甲烷气,近海的甲烷水合物被认为是一种非常重要的天然能源。

关键词：海洋气水合物资源天然气海底瞬时双偶极法

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高功率磁控管的现代水平

真空电子技术 1966年第6期 20-24页

作者： r.edwards 黄华国

虽然磁控管是最老和最普通的一种微波振荡器,但它仍在大力发展着。近来,在中等功率和高功率磁控管方面所作的大量工作都是致力于获得快速调谐、增加稳定性及可靠性和在较高的频率上得到较大的功率。功率近几年里,从较低频率的L和S波段... 详细信息

虽然磁控管是最老和最普通的一种微波振荡器,但它仍在大力发展着。近来,在中等功率和高功率磁控管方面所作的大量工作都是致力于获得快速调谐、增加稳定性及可靠性和在较高的频率上得到较大的功率。功率近几年里,从较低频率的L和S波段脉冲磁控管所能得到的峰值功率电平已达到饱和状态。速调管、增幅管和其它的放大管在这些波

关键词：磁控管千兆赫波段功率电平翼片雷声公司高功率雷达微波管超高频电子管