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LOD score exclusion analyses for candidate disease susceptibility genes using case-parents design

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Progress in Natural Science:Materials International 2006年第1期16卷 30-38页

作者： DENG Hongwen1,2,3 and GAO Guimin2,4 (1.Laboratory of Molecular and Statistical Genetics, College of Life Sciences, hunan Normal university, changsha 410081, china 2.Osteoporosis research center, Creighton university Medical center, Omaha NE 68131, USA 3. Department of Biomedical Sciences, Creighton university, Omaha NE 68131, USA 4. Virginia Bioin format ics Institute and Department of Statistics, Virginia Polytechnic Institute and State university, Blacksburg VA 24061-0315, USA) [a]Laboratory of Molecular and Statistical Genetics College of Life Sciences Human National University Changsha China [b]Osteoporosis research center Creighton University Medical Center Omaha NE USA [c]Department of Biomedical Sciences Creighton University Omaha NE USA [d]Virginia Bioinformatics Institute and Department of Statistics Virginia Polytechnic Institute and State University Blacksburg VA USA

The focus of almost all the association studies of candidate genes is to test for their importance. We recently developed a LOD score approach that can be used to test against the importance of candidate genes for complex diseases and quantitative traits in random samples. As a complementary method to regular association analyses, our LOD score approach is powerful but still affected by the population admixture, though it is more conservative. To control the confounding effect of population heterogeneity, we develop here a LOD score exclusion analysis using case-parents design, the basic design of the transmission disequilibrium test (TDT) approach that is immune to population admixture. In the analysis, specific genetic effects and inheritance models at candidate genes can be analyzed and if a LOD score is ≤ - 2. 0, the locus can be excluded from having an effect larger than that specified. Simulations show that this approach has reasonable power to exclude a candidate gene having small genetic effects if it is not a disease susceptibility locus (DSL) with sample size often employed in TDT studies. Similar to association analyses with the TDT in nuclear families, our exclusion analyses are generally not affected by population admixture. The exclusion analyses may be implemented to rule out candidate genes with no or minor genetic effects as supplemental analyses for the TDT. The utility of the approach is illustrated with an application to test the importance of vitamin D receptor (VDR) gene underlying the differential risk to osteoporosis.

关键词： association studies candidate genes case-parents design disease susceptibility locus exclusion mapping LOD score.

Bioinformatics analyses for signal transduction networks

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Science china(Life Sciences) 2008年第11期51卷 994-1002页

作者： LIU Wei1,2, LI Dong2, ZHU YunPing2 & HE FuChu1,2 1 College of Mechanical & Electronic Engineering and Automatization, National university of Defense Technology, changsha 410073, china 2 State Key Laboratory of Proteomics, Beijing Proteome research center, Beijing Institute of Radiation Medicine, Beijing 102206, china 1. College of Mechanical & Electronic Engineering and Automatization National University of Defense Technology Changsha 410073 China 2. State Key Laboratory of Proteomics Beijing Proteome Research Center Beijing Institute of Radiation Medicine Beijing 102206 China

research in signaling networks contributes to a deeper understanding of organism living activities. With the development of experimental methods in the signal transduction field, more and more mechanisms of signaling pathways have been discovered. This paper introduces such popular bioin-formatics analysis methods for signaling networks as the common mechanism of signaling pathways and database resource on the Internet, summerizes the methods of analyzing the structural properties of networks, including structural Motif finding and automated pathways generation, and discusses the modeling and simulation of signaling networks in detail, as well as the research situation and tendency in this area. Now the investigation of signal transduction is developing from small-scale experiments to large-scale network analysis, and dynamic simulation of networks is closer to the real system. With the investigation going deeper than ever, the bioinformatics analysis of signal transduction would have immense space for development and application.

关键词： signal transduction structural motif automated pathways regeneration dynamics simulation

Molecular dynamics simulation of kink in 〈100〉 edge dislocation in body centred cubic iron

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Chinese Science Bulletin 2007年第16期52卷 2291-2296页

作者： CHEN LiQun1,2,WANG ChongYu2,3,4 & YU Tao2 1 College of Sciences,Central South university of Forestry & Technology,changsha 410004,china 2 Central Iron and Steel research Institute,Beijing 100081,china 3 Department of Physics,Tsinghua university,Beijing 100084,china 4 International center for Materials Physics,Chinese Academy of Sciences,Shenyang 110016,china College of Sciences Central South University of Forestry and Technology Changsha 410004 China

Using the molecular dynamics method,we have constructed two kink models corresponding to the 〈100〉{010} and 〈100〉{011} edge dislocations (EDs) in body centred cubic (bcc) Fe. It is found that the geometric structure of a kink depends on the type of edge dislocation and the structural energies of the atoms sites in the dislocation core region. The formation energies,migration energies and widths of the kinks in different types of EDs are calculated. The results show that formation and migration of the kink in the 〈100〉{010} edge dislocation are difficult. The 〈100〉{011} edge dislocation moves primarily through kink nucleation,rather than kink migration.

关键词：分子动力学边缘位移铁纽结结构

The effect of hydrogen on the electronic structure of kink in bcc iron

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Science china(Technological Sciences) 2009年第5期52卷 1212-1218页

作者： CHEN LiQun1,QIU ZhengChen1,YU Tao2 & WANG ChongYu2,3,4 1 College of Sciences,Central South university of Forestry and Technology,changsha 410004,china 2 Central Iron and Steel research Institute,Beijing 100081,china 3 Department of Physics,Tsinghua university,Beijing 100084,china 4 International center for Materials Physics,Chinese Academy of Sciences,Shenyang 110016,china 1. College of Sciences Central South University of Forestry and Technology Changsha 410004 China 2. Central Iron and Steel research Institute Beijing 100081 China 3. Department of Physics Tsinghua University Beijing 100084 China 4. International center for Materials Physics Chinese Academy of Sciences Shenyang 110016 China

The electronic structures of kinks in the [100](010) and 1/2[111](-110) edge dislocations in bcc iron containing hydrogen are investigated by means of the first-principles DMol method and the discrete variational *** effects of hydrogen on the kinks are *** results show that hydro-gen forms weak bonding states with its neighboring host atoms,and since hydrogen draws charge from its neighboring host atoms,the interactions between most of the host atoms are weakened com-pared with those of the corresponding atomic pairs in the clean *** indicates that the migration of kink,*** motion of dislocation,is easier in the doping hydrogen kink than in the clean kink,which may be the solid solution softening effect resulting from the impurity hydrogen.

关键词： electronic structure dislocation kink impurity

P2P traffic optimization

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Science china(Information Sciences) 2012年第7期55卷 1475-1492页

作者： ZHANG GuoQiang 1,2 ,TANG MingDong 3 ,CHENG SuQi 2,4 ,ZHANG GuoQing 2 ,SONG HaiBin 5 ,CAO JiGuang 6 & YANG Jing 7 1 School of Computer Science and Technology,Nanjing Normal university,Nanjing 210046,china 2 Institute of Computing Technology,Chinese Academy of Sciences,Beijing 100190,china 3 School of Computer Science and Engineering,hunan university of Science and Technology,Xiangtan 411201,china 4 Graduate university of Chinese Academy of Sciences,Beijing 100190,china 5 Nanjing R&D center,Huawei technologies,Nanjing 210012,china 6 china Academy of Telecommunication research of MIIT,Beijing 100191,china 7 china Mobile research Institute,Beijing 100053,china 1. School of Computer Science and Technology Nanjing Normal University Nanjing 210046 China2. Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China3. School of Computer Science and Engineering Hunan University of Science and Technology Xiangtan 411201 China4. Graduate University of Chinese Academy of Sciences Beijing 100190 China5. Nanjing R&D Center Huawei Technologies Nanjing 210012 China6. China Academy of Telecommunication Research of MIIT Beijing 100191 China7. China Mobile Research Institute Beijing 100053 China

Peer-to-peer (P2P) based content distribution systems have emerged as the main form for content distribution on the Internet,which can greatly reduce the distribution cost of content providers and improve the overall system ***,the mismatch between the overlay and underlay networks causes large volume of redundant traffic,which intensifies the tension between P2P content providers and ***,how to efficiently use network resources to reduce the traffic burden on the ISPs is crucial for the sustainable development of P2P *** paper surveys the state-of-art P2P traffic optimization technologies from three perspectives:P2P cache,locality-awareness and data *** details,comparison between these technologies and their applicabilities are presented,followed by a discussion of the issues that remain to be addressed and the direction of future content distribution research.

关键词： P2P traffic localization P2P traffic optimization P2P cache locality-awareness network coding content-centric network

THE　EFFECT　OF　SILICON　ADDITIVE　ON　THESTRUCTURE　AND　PROPERTIES　OFC－B_4C－SiC　COMPOSITE

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Acta Metallurgica Sinica(English Letters) 1996年第3期9卷 206-210页

作者： HUANG Qizhong YANG Qzaoqin and WU Lijun(Powder Metallurgy research institute, Central Sonth university of Technology, changsha 410083, china Materials research and Test center, Hnnan university, changsha 410082, chinaLab. of Atomic Imaging of Solids, Ins

A Preliminary study of the effect of silicon additive on the structure and properites of C-B_4C-SiC composite was conducted. A liquid Phase has formed and the liquid Si reacts with C to form SiC at the grain boundary when sintering, which accelerates the sintering process and retards the grain growth. Consequently, the density and strength of the composite increase markedly. And the increase in the density increases the oxidation resistance and decreases the specific resistance of the composite. Furthermore,the C-B_4 C-SiC composite has good heat-shock resistance. The phenomena may be dueto the strengthening and toughening of microcracks.

关键词： Si additive C-B_4C-SiC composite structure and property

The age of synthesis:From cognitive science to converging technologies and hereafter

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Chinese Science Bulletin 2011年第6期56卷 465-475页

作者： CAI ShuShan1,2 1 Department of Psychology, Tsinghua university, Beijing 10084, china 2 center for Psychology and Cognitive Science, Tsinghua university, Beijing 10084, china Department of Psychology Tsinghua University center for Psychology and Cognitive Science Tsinghua University

This paper describes the development of two of the most important scientific disciplines in the last quarter of the 20th century, cognitive science, which emerged in 1975, and nano-bio-info-cogno (NBIC) converging technologies, which emerged in 2000. In this century, we will achieve cross-disciplinary integration, innovation in comprehensive knowledge and comprehensive devel opment in human resources. NBIC converging technologies will greatly expand human cognition and communication, improve human health, enhance social outcomes, strengthen national security and unify science and education. Cognitive science and converging technologies will have major effects on the future human development. I argue that the 21st century represents an age of synthesis, reflected in the continual reintegration between scientific disciplines in recent times. This new age of synthesis will require innovations in thought and methodology that differ from those underlying the age of analysis in the 20th century. I predict that these developments will allow every individual to realize comprehensive development. Accordingly, the education system will be transformed, and a comprehensive human resources system will be created.

关键词：认知科学融合技术化学合成教育系统人力资源人类健康生物信息综合知识

A Study on a Partially Immersed Gold Electrode Using an Electrochemical Quartz Crystal Impedance System

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Chinese Chemical Letters 2000年第9期11卷 809-812页

作者： Qing Ji XIE You Yu ZHANG Ming SUN Ling YI Shou Zhuo YAO Chemical research Institute, hunan Normal university, changsha 410081 hunan Normal Univ Inst Chem Res Changsha 410081 Peoples R China

The electrochemical quartz crystal impedance system (EQCIS) has been used for the study of a partially immersed Au electrode in 0.2 mol/L NaClO4 aqueous solution. The influences of the immersed area and height of the electrode on the EQCIS responses were evaluated, showing the highest response sensitivity to liquid loading at the center of the piezoelectric quartz crystal electrode. The increase in the immersed height of the Au electrode at oxygen reduction potentials during potential cycling was measured by this technique.

关键词： electrochemical quartz crystal impedance system (EQCIS) equivalent circuit parameters electrochemical impedance partially immersed Au electrode

Experimental Study of Sediment Incipience Under Complex Flows

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Transactions of Tianjin university 2008年第4期14卷 300-306页

作者： LIU Chunrong DENG Liying HUANG Zhenhua HUHE Aode Maritime research center School of Civil and Environmental Engineering Nanyang Technological University Singapore 639798 College of Mechanics and Aerospace Hunan University Changsha 410082 China School of Civil and Environmental Engineering Nanyang Technological University Singapore 639798 Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Sediment incipience under flows passing a backward-facing step was studied. A series of experiments were conducted to measure scouring depth, probability of sediment incipience, and instantaneous flow velocity field downstream of a backward-facing step. Instantaneous flow velocity fields were measured by using Particle Image Velocimetry (PIV), and an image processing method for determining probability of sediment incipience was employed to analyze the experimental data. The experimental results showed that the probability of sediment incipience was the highest near the reattachment point, even though the near-wall instantaneous flow velocity and the Reynolds stress were both much higher further downstream of the backward-facing step. The possible me- chanisms are discussed for the sediment incipience near the reattachment point.

关键词： sediment transport local scour complex flows particle image velocimetry sediment incipience