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1A complete sequence and comparative analysis of a SARS-associated virus(Isolate BJ01)显示文摘The genome sequence of the Severe Acute Respiratory Syndrome (SARS)-associated virus provides essential information for the identification of pathogen(s), exploration of etiology and evolution, interpretation of transmission and pathogenesis, development of diagnostics, prevention by future vaccination, and treatment by developing new drugs. We report the complete genome sequence and comparative analysis of an isolate (BJ01) of the coronavirus that has been recognized as a pathogen for SARS. The genome is 29725 nt in size and has 11 ORFs (Open Reading Frames). It is composed of a stable region encoding an RNA-dependent RNA polymerase (composed of 2 ORFs) and a variable region representing 4 CDSs (coding sequences) for viral structural genes (the S, E, M, N proteins) and 5 PUPs (putative uncharacterized proteins). Its gene order is identical to that of other known coronaviruses. The sequence alignment with all known RNA viruses places this virus as a member in the family of Coronaviridae. Thirty putative substitutions have been identified by comparative analysis of the 5 SARS- associated virus genome sequences in GenBank. Fifteen of them lead to possible amino acid changes (non-synonymous mutations) in the proteins. Three amino acid changes, with predicted alteration of physical and chemical features, have been detected in the S protein that is postulated to beinvolved in the immunoreactions between the virus and its host. Two amino acid changes have been detected in the Mprotein, which could be related to viral envelope formation. Phylogenetic analysis suggests the possibility of non-human origin of the SARS-associated viruses but provides noevidence that they are man-made. Further efforts should focus on identifying the etiology of the SARS-associated virus and ruling out conclusively the existence of otherpossible SARS-related pathogen(s).QIN E'de ZHU Qingyu YU Man FAN Baochang CHANG Guohui SI Bingyin YANG Bao PENG Wenming JIANG Tao LIU Bohua DENG Yongqiang LIU Hong ZHANG Yu WANG Cui LI Yuquan GAN Yonghua LI Xiaoyu L Fushuang TAN Gang CAO Wuchun, YANG Ruifu Institute of Microbiology and Epidemiology, Chinese Academy of Military Medical Sciences, Beijing 100071, China WANG Jian, LI Wei, XU Zuyuan, LI Yan, WU Qingfa, LIN Wei, CHEN Weijun, TANG Lin, DENG Yajun, HAN Yujun, LI Changfeng, LEI Meng, LI Guoqing, LI Wenjie, L Hong, SHI Jianping, TONG Zongzhong, ZHANG Feng, LI Songgang, LIU Bin, LIU Siqi, DONG Wei, WANG Jun, Gane K-S Wong, YU Jun & YANG Huanming* Beijing Genomics Institute, Chinese Academy of Sciences, Beijing 101300 National Center for Genome Information, Beijing 101300, China 2003Chinese Science Bulletin2003,48,10:121
2Multi-level decollement zones and detachment deformation of Longmenshan thrust belt,Sichuan Basin,southwest China显示文摘As is well known that many decollement layers were developed in the Longmenshan thrust belt,Si-chuan Basin,China. Through field investigation,explanation of seismic profiles and analysis of the balanced sections,we can divide the decollement zones into 3 categories: (1) the deep level decolle-ment zones,including the crust-mantle decollement layer,intracrustal decollement layer,and presinian basal decollement layer. The main structural styles of their deformation are the crust-mantle decoup-ling detachment deformation,the basal ductile shear deformation,etc.; (2) the middle level decollement zones,including the Cambrian-Ordovician decollement layer,the Silurian decollement layer,etc.,the main structural styles of their deformation are the isopachous fold,the angular fold,the saddle struc-ture,and the combination styles of them; and (3) the shallow level decollement zones,including the Xujiahe Formation decollement layer of Upper Triassic and the Jurassic decollement layers,the main structural styles of their deformation are the thrust-nappe tectonic,the pop-up,the triangle zone ,the duplex,etc. Multi-level decollement zones not only made the Longmenshan thrust belt develop many different deformation styles from deep place to shallow place,but also made some local areas have the superimposition of the tectonic deformation apparently. This study indicates that the multi-level de-collement zones have a very important effect on the shaping and evolution of the Longmenshan thrust belt.TANG LiangJie1,2,3,YANG KeMing4,JIN WenZheng1,2,3,L ZhiZhou4 & YU YiXin1,2,3 1 State Key Laboratory of Petroleum Resource and Prospecting,China University of Petroleum,Beijing 102249,China 2 Key Laboratory for Hydrocarbon Accumulation Mechanism,China University of Petroleum,Ministry of Education,Beijing 102249,China 3 Basin and Reservoir Research Center,China University of Petroleum,Beijing 102249,China 4 Southwest Division Company,SINOPEC,Chengdu 610081,China 2008Science China Earth Sciences2008,51,S2:18
3Primary scientific results of Chang'E-1 lunar mission显示文摘The strategic plan for the development of the unmanned Chinese Lunar Exploration Program is characterized by three distinct stages: 'orbiting around', 'landing on' and 'returning from' the Moon. The first Chinese lunar probe, Chang'E-1, which was successfully launched on October 24th, 2007 at Xichang Satellite Launch Center, and guided to crash on the Moon on March 1st, 2009, at 52.36°E, 1.50°S, in the north of Mare Fecunditatis, is the first step towards the 'orbiting around' stage. The Chang'E-1 mission lasted 495 days, exceeding the expected life-span by about four months. A total of 1.37 TB raw data was received from Chang'E-1. It was then processed into 4 TB scientific data products at various levels. Many scientific results have been obtained by analyzing these data, including especially the 'global lunar image from the first Chinese lunar explora- tion mission'. All scientific goals of Chang'E-1 have been achieved. It provides much useful materials for further advances of lunar sciences and planetary chemistry. Meanwhile, these results will serve as a firm basis for future Chinese lunar missions.OUYANG ZiYuan1,2, LI ChunLai1, ZOU YongLiao1, ZHANG HongBo1, Lü Chang1, LIU JianZhong1, LIU JianJun1, ZUO Wei1, SU Yan1, WEN WeiBin1, BIAN Wei1, ZHAO BaoChang3, WANG JianYu4, YANG JianFeng3, CHANG Jin5, WANG HuanYu6, ZHANG XiaoHui7, WANG ShiJin7, WANG Min1, REN Xin1, MU LingLi1, KONG DeQing1, WANG XiaoQian1, WANG Fang1, GENG Liang1, ZHANG ZhouBin1, ZHENG Lei1, ZHU XinYing1, ZHENG YongChun1, LI JunDuo1, ZOU XiaoDuan1, XU Chun1, SHI ShuoBiao1, GAO YiFei1 & GAO GuanNan1 1 National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China 2 Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China 3 Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China 4 Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China 5 Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China 6 Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China 7 Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190, China 2010Science China Earth Sciences2010,53,11:11
4Genetic regulation of programmed cell death in Drosophila显示文摘Programmed cell death plays an important role in maintaining homeostasis during animal development, and has been conserved in animals as different as nematodes and humans. Recent studies of Drosophila have provided valuable information toward our understanding of genetic regulation of death. Different signals trigger the novel death regulators rpr, hid, and grim, that utilize the evolutionarily conserved iap and ark genes to modulate caspase function. Subsequent removal of dying cells also appears to be accomplished by conserved mechanisms. The similarity between Drosophila and human in cell death signaling pathways illustrate the promise of fruit mes as a model system to elucidate the mechanisms underlying regulation of programmed cell death.LEE CHENG-YU, ERIC H BAEHRECKE (l Center for Agricultural Biotechnology, University of Maryland Biotechnology institute, College Park, Maryland 20742,USA Department of Biology, University of Maryland, College Park, Maryland 20742, USA) 2000Cell Research2000,10,3:11
5A heuristic path-estimating algorithm for large-scale real-time traffic information calculating显示文摘As the original Global Position System (GPS) data in Floating Car Data have the accuracy problem,this paper proposes a heuristic path-estimating algorithm for large-scale real-time traffic information calculating. It uses the heuristic search method,imports the restriction with geometric operation,and makes comparison between the vectors composed of the vehicular GPS points and the special road network model to search the set of vehicular traveling route candidates. Finally,it chooses the most optimal one according to weight. Experimental results indicate that the algorithm has considerable efficiency in accuracy (over 92.7%) and com-putational speed (max 8000 GPS records per second) when handling the GPS tracking data whose sampling rate is larger than 1 min even under complex road network conditions.L WeiFeng1,ZHU TongYu1,WU DongDong2,DAI Hong3 & HUANG Jian1 1 State Key Laboratory for Software Development Environment,Beihang University,Beijing 100083,China 2 Beijing Transportation Information Center,Beijing 100055,China 3 College of Arts & Science,Beijing Union University,Beijing 100083,China 2008Science China(Technological Sciences)2008,51,S1:7
6Relation of ice conditions to climate change in the Bohai Sea of China显示文摘The ice conditions in the Bohai Sea and the northern Huanghai Sea greatly change from year to year with winter climate. Ice only covers below 15% of the the waters during the wannest win-ter, while it covers more than 80% during the coldest winter. Ice observation and data acquisition are outlined in the paper. The ice-covered area, the position of ice edge and the ice grades give indication of the ice conditions. The local climate of the waters can be expressed by using the air temperature of the stations of Dalian and Yingkou. The variation of the ice condition indexes with the monthly mean air temperature at Dalian from 1952 to 2000 is shown, as well. The local climate and ice conditions in the waters are affected by many factors,such as, evolution of the general atmospheric circulation and the solar activity. The delayed correlation between the ice conditions and lots of the affecting factors is analysed in the paper. The ice conditions are continuously mild since the 1990s, that is relative to the tendency of the global warming. The ice condition variation of the Bohai Sea is related to the El Nino event and the sunspot period. The seasonal evolution of the ice conditions is also described in the paper.Bai Shan, Liu Qinzheng, Wu Huiding I. National Center fOr Marine Environmnt FOrecats, ffeijing l(XX)8I. China. 2001Acta Oceanologica Sinica2001,20,3:7
7Solvothermal synthesis of crystalline carbon nitrides显示文摘A solvothermal reaction of anhydrous C3N3Cl3 and Li3N using benzene as the solvent has been carried out to prepare crystalline carbon nitrides successfully at 350℃ and 5—6 MPa. X-ray diffraction (XRD) indicated that the major part of our brown sample was mainly composed of a-C3N4 and b-C3N4 with lattice parameters of a = 0. 65 nm, c = 0.47 nm for a-C3N4 and a = 0.644 nm, c = 0. 246 nm for b-C3N4, which match the latest ab-initio calculations quite well. The N/C ratio in the powder is about 0.66. The Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spec-troscopy (XPS) analyses suggested the presence of both sin-gle and double carbon-nitrogen bonds. The kinetics effects of our solvothermal reaction to prepare crystalline carbon ni-trides are also discussed chiefly.L Qiang, CAO Chuanbao & ZHU Hesun Research Center of Materials Science, Beijing Institute of Technology, Beijing 100081, China 2003Chinese Science Bulletin2003,48,6:4
8Inducible resistance to Fas-mediated apoptosis in B cells显示文摘Apoptosis produced in B cells through Fas (APO-1, CD95) triggering is regulated by signals derived from other surface receptors: CD40 engagement produces upregulation of Fas expres. sion and marked susceptibility to Fas-induced cell death, whereas antigen receptor engagement, or IL-4R engagement, inhibits Fas killing and in so doing induces a state of Fas-resistance, even in otherwise sensitive, CD40-stimulated targets. Surfaceim. munoglobulin and IL-4R utilize at least partially distinct pathways to produce Fas-resistance that differentially depend on PKC and STAT6, respectively. Further, surface immunoglob- 'lin signaling for inducible Fas-resistance bypasses Bib, requires NF-GB, and entails new macromolecular synthesis. Terminal effectors of B cell Fas-resistance include the known anti-apoptotic gene products, Bcl-xL and FLIP, and a novel anti-apoptotic gene that encodes FAIM (Fas Apoptosis Inhibitory Molecule). faim was identified by differential display and exists in two alternatively spliced forms; maim-S is broadly expressed, but faim-L expression is tissue-specific. The FAIM sequence is highly evolu tionarily conserved, suggesting an important role for this molecule throughout phylogeny. Inducible resistance to Fas killing is hypothesized to protect foreign antigen-specific B cells during potentially hazardous interactions with FasL-bearing T cells, whereas autoreactive B cells fail to become Fas-resistant and are deleted via Fas-dependent cytotoxicity. Inadvertent or aberrant acquisition of Fas-resistance may permit autoreactive B cells to escape Fas deletion, and malignant lymphocytes to impede anti-tumor immunity.ROTHSTEIN THOMAS L Departments of Medicine and Microbiology, and the Evans Memorial Department of Clinical Research, Boston University Medical Center, Boston, MA, USA 2000Cell Research2000,10,4:4
9The spatial and temporal distribution of microalgae in the South China Sea:evidence from GIS-based analysis of 18S rDNA sequences显示文摘The purpose of this study was to estimate the spatial and temporal variation of microalgae in the South China Sea and to demonstrate the environmental factors controlling the diversity of microalgae by GIS (geographic information system)-based analysis of 18S rDNA sequences. Six 18S rDNA libraries were constructed from environmental samples collected at different sites in the study area, and more than 600 18S rDNA sequences were determined. The rDNA sequence data were then analyzed by DIVA-GIS software to display the spatial and temporal variation of phytoplankton’s composition. It was shown that the autotrophic eukaryotic plankton dominated over the heterotrophic cells in most of our clone libraries, and the dominating phytoplankton was Dinophyceae except for Bacillariophyta at the Xiamen harbor. The percentages of these two groups were controlled by water temperature and salinity. Our results also revealed that the species composition of Chlorophyta showed a close relationship with latitude, changing from Prasinophyceae at the high latitude to Trebouxiophyceae at the low latitude. Several newly classified picoplankton lineages were first uncovered in the South China Sea, including the pico-sized green alga Ostreococcus sp. and Picochlorum eukaryotum, and picobiliphytes, which was just discovered in 2007 with unknown affinities to other eukaryotes. Their spatial and temporal variation were also analyzed and discussed.LI LüYan1, HUANG QiaoJuan1, WU ShuHui1, LIN Duan2, CHEN JiaHui2 & CHEN YueQin1 1 Key Laboratory of Gene Engineering of the Ministry of Education, State Key Laboratory for Biocontrol, Sun Yat-Sen University, Guangzhou 510275, China 2 South China Sea Environmental Monitoring Center, State Oceanic Administration, Guangzhou 510300,China 2008Science China(Life Sciences)2008,51,12:2
10Colossal magnetoresistive p-n junctions of perovskite oxide La_(0.9)Sr_(0.1)MnO_3/SrNb_(0.01)Ti_(0.99)O_3显示文摘We have successfully fabricated the colossal magnetoresistive (CMR) p-n junctions of perovskite oxide La0.9Sr0.1MnO3/SrNb0.01Ti0.99O3 (LSMO/SNTO) with laser molecular beam epitaxy. The I-V characteristics of the LSMO/SNTO p-n junctions as a function of applied magnetic field (05 T) were studied between 100 and 300 K. We found that the p-n junction exhibited the CMR behavior. The CMR ratio rR/R0 (rR = RH - R0) is positive in magnetic fields below 0.13 T and at high temperature, while it displays a negative CMR near 100 K and in magnetic fields over 0.13 T. The CMR ratio values are 8% at 0.1 T and 13% at 5 T and 300 K, 40% at 0.1 T and 150 K, 10% at 0.13 T and 60% at 5 T and 100 K. The CMR behavior of the p-n junction is different from those of the LaMnO3 compound family.L Huibin, DAI Souyu, CHEN Zhenghao, YAN Lei, ZHOU Yueliang & YANG Guozhen Laboratory of Optical Physics, Institute of Physics & Center for Condensed Matter Physics, Chinese Academy of Sciences, 100080 Beijing, China 2003Chinese Science Bulletin2003,48,13:2
11New synthesis of amphiphilic copolymers PE-g-PEO via esterfication显示文摘A new series of high molecular weight amphi-philic graft copolymers PE-g-PEO has been prepared. The esterifications between PE-p-MS-g-MA and PEO with OH group at the chain end are carried out under different condi-tions. The compositions of these graft copolymers are studied by NMR and FTIR. It is found to be a convenient and effi-cient way to prepare high molecular weight PE-g-PEO graft copolymers.L?Yingying1, MA Zhi1,2, HU Youliang1, XU G. X.3 & CHUNG T. C.3 1. State Key Laboratory of Engineering Plastics, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Bei-jing Beijing Lab of Catalysis, Key Lab of Catalysis of China Na-tional Petroleum Corporation, Beijing 100080, China 2. Graduate School of Chinese Academy of Sciences, Beijing 100039, China 3. Department of Material Science and Engineering, Pennsylvania State University, University Park, PA 16802, USA 2003Chinese Science Bulletin2003,48,6:2
12AFM study on the adsorption and aggregation behavior of dissolved humic substances on mica显示文摘Humic substances constitute the major organic fractions of soils, sediments and natural waters, and play a dominant role in the binding, mobilization, transport and ultimate fate of organic contaminants in subsurface systems. In this paper, two humic acid samples, Guanting and Tianjin, with different origin and chemical compositions have been investigated with AFM imaging for their adsorption and aggregation behaviors on mica. While the Tianjin humic sample is found to form small spheres with 250 to 330 nm in diameter at lower concentrations, irregular loop-chain assemblies of hundreds of nanometer in diameter with the chain width of about 40 nm are dominant for the Guanting humic sample, which may attribute to the more polar aliphatic fractions in the chemical composition in the latter. The heterogeneous and polydisperse nature of humic substances with multiple structural features, such as sponge-like structures, perforated sheets, aggregate of spheres, branches and chain-like assemblies etc., is apparent at higher concentrations for both humic samples, showing morphologically new evidence for the dominant view of the humic dual-mode sorption model. With naphthalene introduced, the assemblies of Guanting humic substances clearly become more compact with significantly narrowed branches and less porous the perforated sheet-like structures. It is indica- tive of that smaller nanometer scale rings present along the perforated assemblies could potentially represent hydrophobic domains, which may facilitate the adsorption and aggregation of naphthalene onto the natural particle surfaces and therefore lead to an important role of dissolved humic sub- stances in the sorption of environmental pollutants.GE Xiaopeng1, ZHOU Yanmei2, Lü Chunhua1 & TANG Hongxiao1 1. State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China 2. School of Civil Engineering & Architecture, Beijing Jiaotong University, Beijing 100044, China 2006Science China Chemistry2006,49,3:1
13The effects of Sadenosylmethionine on clinical pathology and redox potential in the red blood cell,liver, and bile of clinically normal cats显示文摘Center S A Randolph J F Warner K L 2005J Vet Intern Med2005,19,3:1
14显示文摘L Huibin DAI Souyu CHEN Zhenghao YAN Lei ZHOU Yueliang & YANG Guozhen Laboratory of Optical Physics Institute of Physics & Center for Condensed Matter Physics Chinese Academy of Sciences 100080 Beijing China 2003Chinese Science Bulletin2003,,13:1
151989,Guidelines for preventionof human immuno logy efficiency virus and hepatitis Bvirus tohealthcare and public safety workers显示文摘Centers fo rD isease Contro l 1989MMWR1989,38,:1
16Current status of hemodialysis treatment in Beijing,China显示文摘Zuo L Wang M Beijing Hemodialysis Quality Control and Improvement Center 0,,2:1
17Worldwide variations in colorectal cancer 显示文摘Center MM Jemal A Smith RA et a l 2009CA Cancer J Clin2009,59,6:1
18follow-up of 9 years显示文摘Gracida C Melchor J L Espinoza R Experience in a single transplant center with 421 living donors 2002Transplant Prec2002,34,:1
19Current status of hemodialysis treatment in Beijing, China显示文摘Zuo L Wang M Beijing Hemodialysis Quality Control and Improvement Center 2006Ethn Dis2006,16,22:1
20Integrated precise orbit determination of Shenzhou IV unmanned spacecraft显示文摘Considering the characteristic orbit of Shenzhou IV spacecraft and the advantages and disadvantages of several types of domestic orbit measurements, a scheme of IPOD is determined, which uses GPS, SLR and USB observation data jointly plus precise ionosphere corrections to GPS observation data. IPOD system and mathematic models of OD are introduced. The results of different joint OD are analyzed using true observation data, and show that radial accuracy is better than 2 m.L Congmin1,2, GU Yidong3, LIN Baojun3 & GUO Jiong3 1. Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100080, China 2. Graduate School of the Chinese Academy of Sciences, Beijing 100039, China 3. General Establishment of Space Science and Application, Chinese Academy of Sciences, Beijing 100080, China Correspondence should be addressed to L Congmin 2004Science China(Technological Sciences)2004,47,5:1
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