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    题名 作者 年代 出处 被引量
1METAMORPHIC MECHANISMSAND THEIR CONFIGURATION MODELS显示文摘The concept of metamorphic mechanisms is presented, configuration models and configuration transformations relating to a set of new matrix operations are discussed and proposed. The configuration of a metamorphic mechanism reflects the connectivity change in the mechanism during motions which results in mobility change and presents the characteristics of the mechanism which is discussed in various applications particularly in decorative artifacts. The characteristics is further investigated with mobility analysis.Dai Jiansheng (Department of Mechanical Engineering, School of Physical Sciences and Engineering, King’s College, University of London,Strand,London WC2R 2LS, United kingdom) Zhang Qixian (Robotics Research Institute,Beijing University of Aeronautics and 2000Chinese Journal of Mechanical Engineering2000,13,3:61
2The common language of space:a way of looking at the social,economic and environmental functioning of cities on a common basis显示文摘This paper proposes that in addition to urban research which seeks to provide answers to policy questions, there is also a need for research which directly addresses the physical and spatial complexity of the built environment itself, and explores any effects it may in itself have on the functioning of the urban system. This type of research reflects the questions architects and urban designers typically ask, rather than those that preoccupy planners. For such research to be effective, the physical complexity variable must be controlled at the level at which real design decisions are made. “Space syntax” research attempts to do this by treating built environments as systems of space, analysing them “configurationally”, and trying to bring to light their underlying patterns and structures. Results from space syntax research into many aspects of urban space and how it works show a consistency which suggests that analysing spacial structure can be a general means of investigating the structure and function of cities. It may, in effect, be the common language of the city.Bill Hillier Bartlett School of Graduate Studies, University College London, Gower Street, London WC1E 6BT, U.K. E\|mail:b.hillier@ucl.ac.uk 1999Journal of Environmental Sciences1999,11,3:18
3Ampullary carcinoma:Effect of preoperative biliary drainage on surgical outcome显示文摘AIM: To evaluate the influence of preoperative biliary drainage on morbidity and mortality after surgical resection for ampullary carcinoma. METHODS: We analyzed retrospectively data for 82 patients who underwent potentially curative surgery for ampullary carcinoma between September 1993 and July 2007 at the Singapore General Hospital, a tertiary referral hospital. Diagnosis of ampullary carcinoma was confirmed histologically. Thirty-five patients underwent preoperative biliary drainage (PBD group), and 47 were not drained (non-PBD group). The mode of biliary drainage was endoscopic retrograde cholangiopancreatography (n = 33) or percutaneous biliary drainage (n = 2). The following parameters were analyzed: wound infection, intra-abdominal abscess, intra-abdominal or gastrointestinal bleeding, septicemia, biliary or pancreatic leakage, pancreatitis, gastroparesis, and re-operation rate. Mortality was assessed at 30 d (hospital mortality) and also longterm. The statistical endpoint of this study was patient survival after surgery. RESULTS: The groups were well matched for demographic criteria, clinical presentation and operative characteristics, except for lower hemoglobin in the non-PBD group (10.9 ± 1.6 vs 11.8 ± 1.6 in the PBD group).Of the parameters assessing postoperative morbidity, incidence of wound infection was signif icantly less in the PBD than the non-PBD group [1 (2.9%) vs 12 (25.5%)]. However, the rest of the parameters did not differ signif icantly between the groups, i.e. sepsis [10 (28.6%) vs 14 (29.8%)], intra-abdominal bleeding [1 (2.9%) vs 5 (10.6%)], intra-abdominal abscess [1 (2.9%) vs 8 (17%)], gastrointestinal bleeding [3 (8.6%) vs 5 (10.6%)], pancreatic leakage [2 (5.7%) vs 3 (6.4%)], biliary leakage [2 (5.7%) vs 3 (6.4%)], pancreatitis [2 (5.7%) vs 2 (4.3%)], gastroparesis [6 (17.1%) vs 10 (21.3%)], need for blood transfusion [10 (28.6%) vs 17 (36.2%)] and re-operation rate [1 (2.9%) vs 5 (10.6%)]. There was no early mortality in either group. Median survival was 44 mo (95% CI: 34.2-53.8) in the PBD group and 41 mo (95% CI: 27.7-54.3; P = 0.86) in the non-PBD group. CONCLUSION: Biliary drainage before surgery for ampullary cancer significantly reduced postoperative wound infection. Overall mortality was not influenced by preoperative drainage.Sheikh Anwar Abdullah Tarun Gupta Khairul Azhar Jaafar Yaw Fui Alexander Chung London Lucien Peng Jin Ooi Steven Joseph Mesenas 2009World Journal of Gastroenterology2009,15,23:16
4LITHOSPHERE-ASTHENOSPHERE INTERACTION: A COMPARATIVE STUDY ON CENOZOIC AND MESOZOIC BASALTS AROUND BOHAI AREAYigang Xu Weiming Fan and Ge Lin( Guangzhou Institute of Geochemistry , Chinese Academy of Sciences , Guangzhou , P. R, China)(Department of Gedegy, Royal Holoway Univoersity of London, Egham, Surrey, TW20OEX , UK)(Changsha Institute of Geotectonics,Chin 1995Geotectonica et Metallogenia1995,19,4:16
5Crank conditions and rotatability of 3-RRR planar parallel mechanisms显示文摘This paper investigates the rotatability of planar parallel mechanisms by revealing the crank conditions that relate to link parameters.The paper extends the theorem of assemblability and the rotatability criterion and applies these criteria to parallel mechanisms in investigating the crank conditions of a parallel mechanism,leading to classification of three types of crank existing conditions including three-crank’s,six-crank’s and nine-crank’s of 3-RRR planar parallel mechanisms.The results are summarized as constraint conditions in relation with link parameters with a concluding table and case studies.LI RuiQin 1 &DAI Jian S 2 1 College of Mechanical Engineering and Automation,North University of China,Taiyuan 030051,China 2 Department of Mechanical Engineering,King’s College London,University of London,WC2R 2LS,UK 2009Science China(Technological Sciences)2009,52,12:12
6Valuing water quality in China:purpose,approach and policy显示文摘The economic valuation of water quality in a rapidly developing country such as China should be undertaken to determine when the benefits from rapid growth begin to exceed the costs from the same. The best approach is to ascertain the total economic valuation of the environmental resource. This includes all of the various uses of the resource, and even those values that are unconnected to individual use (e.g. natural and aesthetic values). A method known as contingent valuation (CV) is used to ascertain these forms of value. This approach is demonstrated here in an application to river water quality in the Beijing area. A CV study is reported in which Beijing area citizens reported an average willingness to pay about 1.3% of annual income in order to prevent further deterioration of river water quality. Aggregation over the representative population indicates that the perceived cost of further river quality deterioration is in the neighbourhood of USD 60 million. Such a measure provides some indication of the socially desired “stopping point”—— in the pursuit of economic growth at the expense of environmental quality.Timothy Swanson,Brett Day,Susana Mourato Centre for Social and Economic Research on the Global Environment, Department of Economics, and School of Public Policy, University College London, Gower Street, London WC1E 6BT, United Kingdom 1999Journal of Environmental Sciences1999,11,3:12
7Nitric Oxide:from a mysterious labile factor to the molecule of the Nobel Prize Recent progress in nitric oxide research显示文摘NO is now known to be an important messenger molecule in biology.It regulates a variety of functions within cells and tissues including vasodilation, neurotransmission and immunological process. This review will focus on the nitric oxide synthase gene family and recent progress on molecular genetic analysis of NOS1, NOS2 and N0S3 genes.XU WEI MING LI ZHI LIU (The Wolfson Institute for Biomedical Research, The Rayne Institute, University College London, 5 University Street,London WC1E 6JJ) 1998Cell Research1998,8,4:11
8The Call of the Wild(Ⅵ)显示文摘Jack London 泽嘉 2005中学生英语(高中版)2005,,21:8
9The sloshing of stratified liquid in a two-dimensional rectangular tank显示文摘The sloshing of inviscid liquid of stratified density in a rectangular tank is analyzed.As the flow is no longer irrotional,the governing equation is found to be quite different from the Laplace equation used for the liquid of constant density.In particular it contains terms of mixed temporal and spatial derivatives.The problem is solved based on the variable separation method and Laplace transform for the constant Vaisala-Brunt frequency.It is found that the stratification of density may have small effects on those natural frequencies associated with the constant density,but many new natural frequencies have appeared as a result of its effect.WU GuoXiong1,2 1 State Key Laboratory of Ocean Engineering,College of Naval Architecture,Ocean and Civil Engineering,Shanghai Jiao Tong University,Shanghai 200240,China 2 Department of Mechanical Engineering,University College London,Torrington Place,London WC1E 7JE,UK 2011Science China(Physics,Mechanics & Astronomy)2011,54,1:7
10阿片成瘾者中的人格障碍问题显示文摘本文采用多种人格障碍筛查表对接受戒毒治疗的80例阿片成瘾者进行了测查。结果显示,各种人格障碍(personalitydisorders,PDs)的现患率为86%,其中戏剧性PD、依赖性PD、回避性PD和边缘性PD各分别占44%、36%、35%和76%。具有统计学意义的多种PD为:(1)依赖性-回避性(OR值=13.9;95%可信限范围=4.55,42.83);(2)戏剧性-依赖性(OR值=2.8;95%可信限范围=1.11,7.26);(3)边缘性-戏剧性(OR值=5.5;95%可信限范围=1.45,20.87);(4)边缘性-依赖性(OR值=3.9;95%可信限范围=1.04,15.04)。此结果提示,在阿片成瘾者中存在着各种严重的人格障碍。Adenekan Oyefeso, Hamid Ghodse, Carmel Clancy, Vanessa Crawford, Stephen Byrne(Research Evaluation and Monitoring Unit Department of Psychiatry of Addictive Behaviour St George’s Hospital Medical School London SW17 ORE) 1998中国药物依赖性杂志1998,7,2:6
11New approaches to characterizing urban air particles in central London显示文摘Atmospheric particles in central London during July 1996 have been apportioned to sources by two complimentary techniques: (1) morphological characteristics, determined using high power light microscopy; (2) chemical composition determined by energy dispersive spectroscopy. During the study period, the majority of particles were found to be either biological in origin, or from vehicle related combustion processes. Trends in the latter group of particles are explored further. Numbers of particles per cubic metre were determined at an hourly resolution over a period of six days, and were found to be significantly correlated with other traffic pollutants such as benzene and 1,3 butadiene, although there is no relationship with mass of PM10 as measured by a nearby UK Government monitoring station. We suggest in this paper that numbers of particles from car exhausts are more representative of traffic pollution than current estimates which use monitoring by mass.A.W. Mackay *, X. Long *, N.L. Rose *, R.W. Battarbee Environmental Change Research Centre, University College London, 26 Bedford Way, London. WC1H0AP, UK 1999Journal of Environmental Sciences1999,11,3:6
12颈总动脉内径与心血管事件及死亡风险研究:4项队列研究的汇总分析显示文摘颈动脉内径增加是动脉重构的表现,且可能是心血管病的危险因素。研究者评估颈动脉内径与脑卒中、冠状动脉性心脏病、心血管病及全因死亡的关系,并探讨与血压有关的中膜增厚、动脉僵硬、动脉壁应力及动脉硬化等动脉重构过程能否解释此关系。Sedaghat S van Sloten TT Laurent S London GM Pannier Kavousi M Mattace-Raso F Franco OH Boutouyrie P Ikram MA Stehouwer CDA 赵狄 练桂丽 2018中华高血压杂志2018,26,7:4
13ACE与AT1R基因多态性及其相互作用对心衰预后的影响显示文摘郑茵 方壮伟 Barry London Dennis M. McNamara 2005中国热带医学2005,5,3:4
14The Development of Modern Pesticides显示文摘The present paper deals with agrochemicals. The low toxicities to mammals and wild lives, greater selectivity against target organisms, and high levels of activity are particular features of many modern agrochemicals. It is suggested that integrated pest management(IPM), by means of a combination of biological and chemical controls has met with some success and the present approach is to optimize the use of chemicals rather than to eliminate them.Harry R. Hudson 1, WU Jun 2,* and XU Wei-liang 21. Division of Chemistry, School of Biological and Applied Sciences, University of North London, London N7 8DB, UK 2. Department of Chemistry, Zhejiang University, Hangzhou 310027, P.R. China 2002Chemical Research in Chinese Universities2002,18,4:4
15Aerosol retrieval over land by exploiting the synergy of TERRA and AQUA MODIS DATA显示文摘Aerosol retrieval over land from satellite remotely sensed data remains internationally a difficult task. By using MODIS data, the Dark Dense Vegetation (DDV) algorithm aerosol distribution and properties retrieval over land has shown excellent competence. However, this algorithm is re-stricted to lower surface reflectance such as water bodies and dense vegetation, which limits its actual application, and is unable to be used for high reflective surface such as over urban areas. In this paper, we introduce a new aerosol retrieval model by exploiting the Synergy of TERRA and AQUA MODIS data (SYNTAM), which can be used for various ground surfaces, including for high reflective surface. Preliminary validations have been carried out by comparing with AERONET measured data, which shows good accuracy and promising potential. Further research work is undergoing.TANG Jiakui1, XUE Yong1,2, YU Tong3, GUAN Yanning1, CAI Guoyin1 & HU Yincui1 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101, China 2. Department of Computing, London Metropolitan University, 166-220 Holloway Road, London N7 8DB, UK 3. Beijing Environmental Monitor Center, Beijing 100044, China 2006Science China Earth Sciences2006,49,6:4
16IUD Expulsion and its Socio-demographic Determinants in China显示文摘To identify the determinant of the occurrence of IUD expulsion Materials & Methods Based on 25 733 IUD uses from the Chinese Two per Thousand Fertility Survey data, this study examines the patterns and differentials of IUD expulsion rate by characteristics of women, and identifies the socio demographic determinants of IUD expulsion. A Life Table method was used to calculate the cumulative expulsion rate and a random effects discrete time survival model was employed to assess the impact of potential determinants simultaneously on the risk of expelling an IUD. Results Three major findings are observed in this study. First, IUD expulsion was the second main reason, after pregnancy during IUD use, for IUD discontinuation during the first four years of IUD insertion; the expulsion rates were 6.4%, 9.1%, 10.8 %, and 12.0% at 12, 24, 36 and 48 months, respectively. Second, there was a clustering of IUD expulsion: some women experienced repeated IUD expulsions. Third, some socio demographic characteristics and fertility history were associated with the occurrence of IUD expulsion. In particular, the expulsion rate was high among young women, among those with two or more children and among those living in rural areas. Conclusion The above mentioned factors shoald be addressed in order to decrease the IUD expulsion rate and enhance the reprocluctive he alth of women.Duo lao WANG, Dan R. Altmann Medical Statistics Unit, Department of Epidemiology & Population Health, London School of Hygiene and Tropical Medicine, UK 2002Journal of Reproduction and Contraception2002,13,3:4
17Advances in numerical methods for the solution of population balance equations for disperse phase systems显示文摘Accurate prediction of the evolution of particle size distribution is critical to determining the dynamic flow structure of a disperse phase system.A population balance equation(PBE),a non-linear hyperbolic equation of the number density function,is usually employed to describe the micro-behavior(aggregation,breakage,growth,etc.) of a disperse phase and its effect on particle size distribution.Numerical solution is the only choice in most cases.In this paper,three different numerical methods(direct discretization methods,Monte Carlo methods,and moment methods) for the solution of a PBE are evaluated with regard to their ease of implementation,computational load and numerical accuracy.Special attention is paid to the relatively new and superior moment methods including quadrature method of moments(QMOM),direct quadrature method of moments(DQMOM),modified quadrature method of moments(M-QMOM),adaptive direct quadrature method of moments(ADQMOM),fixed pivot quadrature method of moments(FPQMOM),moving particle ensemble method(MPEM) and local fixed pivot quadrature method of moments(LFPQMOM).The prospects of these methods are discussed in the final section,based on their individual merits and current state of development of the field.SU JunWei1,GU ZhaoLin2,3 & XU X.Yun41 Department of Mechanical Engineering and Automation,School of Mechanical Engineering,Xi’an Jiaotong University,Xi’an 710049,China 2 Key Laboratory of Mechanics on Disaster and Environment in Western China,Ministry of Education,Lanzhou 730000,China 3 Department of Environmental Science and Technology,School of Human Settlements and Civil Engineering,Xi’an Jiaotong University,Xi’an 710049,China 4 Department of Chemical Engineering,Imperial College London,London SW7 2AZ,UK 2009Science China Chemistry2009,52,8:3
18Past, present and future of fuel cells显示文摘Though the fuel cell was invented by Grove in 1839,there are no commercially viable products at present.The development of fuel cells can be conveniently divided into three phases exploratory phase(1839-1967).The main emphasis of the work is to increase the area of the three phase interface at the electrode.The problem was solved by Bacon who invented the dual porosity,biporous nickel electrode.He demonstrated the first H 2/O 2 fuel cell(180℃,20atm).This cell was later improved and scaled up to power the Apollo lunar mission.However,the cost is too high for civilian applications and we come to the development phase (1967-2001).The main emphasis has been on the use of Teflon bonded electrodes and novel catalysts(PtRu,Pt/WO 3 and Pt Ru/WO 3 anode catalyst for the anodic oxidation of impure H 2 and methanol.In addition,the recent discovery of gadolinium doped ceria has reduced the operating temperature of solid oxide electrolytes to ~500℃ instead of 1?000℃.From 2001 onwards,we may be entering the breakthrough phase where the most favourable candidates are direct methanol vapor fuel cells and solid oxide electrolyte fuel cells.In the former case,there is a need to reduce the cross over of methanol to the cathode compartment and the development of air cathode catalyst which are less affected by methanol and in the latter case,there is a need to improve the activity of the anode and cathode catalysts.A.C.C.Tseung(School of Chemical and Life Sciences,University of Greenwich,London SE18 6PB,UK) 2002电池2002,32,3:3
19Mineralogical Zonation of Wall-Rock Alteration in Jiaodong Gold Province, North China显示文摘MININGHISTORYGeographicalytheJiaodonggoldprovincecoversalmostthewholeShandongorJiaodongPeninsula,theeasternhalfoftheShandongP...Chen Guangyuan Sun Daisheng Shao Wei Li Shengrong Division of Genetic Mineralogy, China University of Geosciences, Beijing 100083 Fyfe S. William Department of Earth Sciences, University of Western Ontario, London, Ontario, Canada, N6A 5B7 Chen 1999Journal of Earth Science1999,18,1:3
20血管紧张素Ⅱ1型受体基因多态性与心力衰竭预后的相关性研究显示文摘目的评价血管紧张素Ⅱ1型受体(AngiotensinⅡtype 1 receptor,AT1R)基因1166位点A/C基因多态性对心力衰竭预后的影响。方法432例患者来源于美国匹兹堡大学医疗中心的心血管事件基因危险性评价研究组,均有收缩功能障碍性心力衰竭〔射血分数(EF)<0.45〕。入选时间为1996年4月至2001年1月,前瞻性随访患者(26.43±18.19)月,随访终点是死亡或心脏移植。用聚合酶链式反应(PCR)方法鉴定AT1R基因A1166C位点基因型,分析AT1R A1166C基因多态性对心力衰竭患者生存率的影响。结果AT1R纯合子CC型8.6%,纯合子AA型50.0%,杂合子AC型41.4%。三组基因型在年龄、性别、种族、病因、血压和治疗方面无显著性差异,而在NYHA心功能分级的比例有显著性差异,AT1R C等位基因与较低心功能分级密切相关(P=0.04),但随访三组基因型的三年生存率并无显著性差异。结论在本组收缩功能障碍性心力衰竭患者中,AT1R C等位基因仅与较低心功能分级密切相关,并不影响未行心脏移植心力衰竭患者的预后。郑茵 方壮伟 吴智勇 Barry London Dennis M McNamara 2005中国心血管杂志2005,10,6:3
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