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1Reconstruction of precipitation variation from tree rings in recent 1000 years in Delingha, Qinghai显示文摘Using seven well-replicated Qilian juniper (Sabina przewalskii Kom.) ring-width chronologies developed at Zongwulong and Shalike Mts. in the northeastern part of the Qaidam Basin annual precipitation from previous July to current June in the recent 1000 years was re- constructed for Delingha. The reconstruction can capture 63.1% of precipitation variance and the equation was stable over time. For the reconstructed precipitation, wet periods occurred in AD1520—1633 and 1933—2001, whereas dry intervals in 1429—1519 and 1634—1741. In ad- dition, the magnitude in precipitation variation was lower before 1430 with about 15 mm, but it increased to 30 mm during the period of 1430 to 1850. After 1850, the precipitation variance de- creased again. In contrast to the increase in temperature, a decrease in annual precipitation was evident since the 1990s. The agreement in low-frequency variation between the reconstruction and the glacier accumulation and particulate content in Dunde ice cores during the recent several hundred years suggested that the precipitation reconstructed in this study was rather reliable, and represented a regional signal. This 1000-year reconstruction could benefit our understanding of climatic variation in decadal to century-scale in this region, and provide basic data to climate models and to prediction of future climate in the 21st century.SHAO Xuemei1, HUANG Lei1, LIU Hongbin2, LIANG Eryuan1, FANG Xiuqi3 & WANG Lili1 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2. National Climate Center, Beijing 100081, China 3. Beijing Normal University, Beijing 100875, China 2005Science China Earth Sciences2005,48,7:113
2On adjacent-vertex-distinguishing total coloring of graphs显示文摘In this paper, we present a new concept of the adjacent-vertex-distinguishing total coloring of graphs (briefly, AVDTC of graphs) and, meanwhile, have obtained the adjacent-vertex-distinguishing total chromatic number of some graphs such as cycle, complete graph, complete bipartite graph, fan, wheel and tree.ZHANG Zhongfu, CHEN Xiang’en, LI Jingwen, YAO Bing, LU Xinzhong & WANG Jianfang College of Mathematics and Information Science, Northwest Normal University, Lanzhou 730070, China Department of Computer, Lanzhou Normal College, Lanzhou 730070, China Institute of Applied Mathematics, Lanzhou Jiaotong University, Lanzhou 730070, China College of Information and Electrical Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China Institute of Applied Mathematics, Chinese Academy of Sciences, Beijing 100080, China 2005Science China Mathematics2005,48,3:173
3Recent glacial retreat in High Asia in China and its impact on water resource in Northwest China显示文摘Under the impact of climatic warming, the glaciers in the High Asia in China have been retreating continuously with negative glacial mass balance in recent several decades. The retreat became more intensive in the past 10 years. The spatial pattern of the glacial retreat in the High Asia in China is that the smallest magnitude of retreat is in the inland of the Tibetan Plateau, the magnitude increases from the inland to the margin of the Tibetan Plateau, and the largest magnitude at the margin of the Tibetan Plateau. The glacial retreat in the High Asia in China has an important impact on the water resource of the arid regions in Northwest China. This study shows that the glacial retreat in the 1990s has caused an increase of 5.5% in river runoff in Northwest China. In the Tarim River basin, the increase of river runoff is higher than 5.5%.YAO Tandong 1,2 ,WANG Youqing 2 ,LIU Shiying 2,1 ,PU Jianchen 2,1 ,SHEN Yongping 2 & LU Anxin 2,1 1.Institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100029,China 2.Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou 730000,China 2004Science China Earth Sciences2004,47,12:117
4Design of a new dynamical core for global atmospheric models based on some efficient numerical methods显示文摘A careful study on the integral properties of the primitive hydrostatic balance equations for baroclinic atmosphere is carried out, and a new scheme todesign the global adiabatic model of atmospheric dynamics ispresented. This scheme includes a method of weighted equal-areamesh and a fully discrete finite difference method with quadraticand linear conservations for solving the primitive equationsystem. Using this scheme, we established a new dynamical corewith adjustable high resolution acceptable to the availablecomputer capability, which can be very stable without anyfiltering and smoothing. Especially, some important integralproperties are kept unchanged, such as the anti-symmetries of thehorizontal advection operators and the vertical convectionoperator, the mass conservation, the effective energy conservationunder the standard stratification approximation, and so on. Somenumerical tests on the new dynamical core, respectively regardingits global conservations and its integrated performances inclimatic modeling, incorporated with the physical packagesfrom the Community Atmospheric Model Version 2 (CAM2) of NationalCenter for Atmospheric Research (NCAR), are included.WANG Bin, WAN Hui, Jl Zhongzhen, ZHANG Xin, YU Rucong, YU Yongqiang & LIU HongtaoState Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China Department of Computational Mathematics, Academy of Mathematics and System Sciences, Peking University, Beijing 100871, China 2004Science China Mathematics2004,47,z1:92
5The land use and land cover change database and its relative studies in China显示文摘In the mid-1990s, we established the national operative dynamic information serving systems on natural resources and environment. During building the land-use/land-cover change (LUCC)database for the mid-1990s, 520 scenes of remotely sensed images of Landsat Thematic Mapper (TM) were interpreted into land-use/land-cover categories at scale of 1:100,000 under overall digital software environment after being geo-referenced and ortho-rectified. The vector map of land-use/land-cover in China at the scale of 1:100,000 was recently converted into a 1-km raster database that captures all ofthe high-resolution land-use information by calculating area percentage for each kind of land use category within every cell. Being designed as an operative dynamic information serving system,monitoring the change in land-use/land-cover at national level was executed. We have completed the updating of LUCC database by comparing the TM data in the mid-1990s with new data sources received during 1999-2000 and 1989-1990. The LUCC database has supported greatly the national LUCC research program in China and some relative studies are incompletely reviewed in this paper.LIU Jiyuan, LIU Mingliang, DENG Xiangzheng, ZhuangDafang,ZHANG Zengxiang, LUO Di(1. Inst. of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China 2. Inst. of Remote Sensing Applications, CAS, Beijing 100101, China) 2002Journal of Geographical Sciences2002,12,3:96
6Homotopic mapping solving method for gain fluency of a laser pulse amplifier显示文摘The model for gain fluency of a laser pulse amplifier is studied. Using the homotopic mapping method, firstly, the system of the original model is packed up standardization; secondly, introducing a homotopic mapping, taking the property of the mapping, inducing a contrived parameter, the solving of a nonlinear problem translates into the solving of a linear problem. Then the approximate expressions of the solution for the corresponding model are obtained. And the precision for the approximate solution is compared. It illuminates that the obtained approximate solution using the homotopic mapping method possesses higher approximate degree. At one time, the expansion of solution through the homotopic mapping method can be kept in the analytic operation. Thus it also enables us through differential and integral operations to obtain other physics behavior for the gain fluency of laser pulse amplifier.MO JiaQi1,2 1 Anhui Normal University, Wuhu 241000, China 2 Division of Computational Science, E-Institutes of Shanghai Universities, at SJTU, Shanghai 200240, China 2009Science China(Physics,Mechanics & Astronomy)2009,52,7:124
7Source mechanism of strong aftershocks (M_s≥5.6) of the 2008/05/12 Wenchuan earthquake and the implication for seismotectonics显示文摘Dozens of >M5, hundreds of >M4, and much more >M3 aftershocks occurred after the 2008/05/12 Wenchuan earthquake, which were well recorded by permanent and portable seismic stations. After relocated with P arrival, the >M3 aftershocks show two trends of distribution, with most of the aftershocks located along the north-east strike consistent with Longmenshan fault system, yet there is a north-west trend around the epicenter. It seems that substantially more aftershocks occur in regions with crystalline bedrocks. Then we collected waveform data from National Digital Seismograph Network and regional seismograph network of China, and employed 'Cut and Paste' method to obtain focal mechanisms and depths of the big aftershocks (M≥5.6). While most of those aftershocks show thrust mechanism, there are some strike slip earthquakes in the northern-most end of the rupture. Focal mechanisms show that the events located on the southern part of central Beichuan-Yingxiu Fault (BY) are mainly thrust earthquakes, which is consistent with initial mechanism of the main shock rupture. In the north part the aftershocks along the BY are also dominated by thrust slip, which is quite different from the right slip rupture of the main shock. Around Qingchuan-Pingwu Fault, the focal mechanisms are dominated by right-slip rupture with large depths (~18 km). So we suspected that in the north part the main shock might rupture on two faults: Beichuan Fault and Qingchuan-Pingwu Fault. The complex pattern of aftershock mechanisms argues for presence of a complicated fault system in the Longmenshan area.ZHENG Yong1,2,MA HongSheng3,Lü Jian4,NI SiDao5,LI YingChun6 & WEI ShengJi2 1 Institute of Geodesy and Geophysics,Chinese Academy of Sciences,Wuhan 430077,China 2 Institute of Geophysics,Chinese Earthquake Administration,Beijing 100086,China 3 Institute of Earthquake Science,Chinese Earthquake Administration,Beijing 100086,China 4 Earthquake Administration of Jiangxi Province,Nanchang 330039,China 5 School of Earth and Space Science,University of Science and Technology of China,Hefei 230026,China 6 Earthquake Administration of Jiangsu Province,Nanjing 210014,China 2009Science China Earth Sciences2009,52,6:100
8Further support for a Cretaceous age for the feathered-dinosaur beds of Liaoning,China:New ^(40)Ar/^(39)Ar dating of the Yixian and Tuchengzi Formations显示文摘We report new 40Ar/39Ar dating results ob-tained from total fusion and incremental-heating analyses of sanidine and biotite from three tuffs found interbedded within the fossil-bearing deposits of Liaoning, northeast China. The first is a new sample of the Bed 6 Sihetun tuff from the Yixian Formation, previously dated by our team as middle Early Cretaceous, and recently considered by Lo et al., partially reset due to metamorphism from a nearby ba-saltic sill. The second is the Yixian Bed 9 tuff from Heng-daozi considered by Lo et al. to be unaffected by metamor-phism and whose age, based on total fusion 40Ar/39Ar dating of biotite, argues for a Jurassic age for the Yixian Formation. The third tuff is a previously undated tuff from the upper part of the underlying Tuchengzi Formation. Single crystal total fusion 40Ar/39Ar analyses of the Sihetun sanidine showed homogeneous radiogenic Ar, Ca/K ratios, excellent reproducibility and gave a mean age of 125.0 ± 0.18 (1SD) ± 0.04 (SE) Ma. Single sanidineC. C. Swisher III, WANG Xiaolin, ZHOU Zhonghe, WANG Yuanqing, JIN Fan, ZHANG Jiangyong , XU Xing, ZHANG Fucheng & WANG YuanDepartment of Geological Sciences, Wright Labs, Rutgers University, Piscataway, New Jersey 08854, USA (e-mail: cswish@rutgers. rci.e 2002Chinese Science Bulletin2002,47,2:83
9SHEsis,a powerful software platform for analyses of linkage disequilibrium,haplotype construction,and genetic association at polymorphism loci显示文摘In multiloci-based genetic association studies of complex diseases, a powerful and high efficient tool for analyses oflinkage disequilibrium (LD) between markers, haplotype distributions and many chi-square/p values with a large numberof samples has been sought for long. In order to achieve the goal of obtaining meaningful results directly from raw data,we developed a robust and user-friendly software platform with a series of tools for analysis in association study withhigh efficiency. The platform has been well evaluated by several sets of real data.Yong Yong SHI1,2, Lin HE2,3,*1Bio-X Life Science Research Center, Shanghai Jiao Tong University, Shanghai, China 2Institute for Nutritional Sciences, Shanghai Institute of Biological Sciences, Chinese Academy of Sciences, Shanghai,China 3NHGG, Bio-X Center, Shanghai Jiao Tong University, Shanghai, China 2005Cell Research2005,15,2:375
10S-rough sets and knowledge separation显示文摘The conceptions of the knowledge screen generated by S-rough sets are given: f- screen and - screen , and then puts forward - filter theorem, - filter theorem of knowledge. At last, the applications of knowledge separation are given according to - screen and - screen.Shi Kaiquan 1,21. School of Mathematics and System Sciences, Liaocheng University, Liaocheng 252059, P. R. China 2. School of Mathematics and System Sciences, Shandong University, Jinan 250100, P. R. China 2005Journal of Systems Engineering and Electronics2005,16,2:104
11瑞舒伐他汀治疗中国高胆固醇血症患者疗效和安全性的随机双盲多中心对照研究显示文摘目的评价瑞舒伐他汀治疗中国高胆固醇血症患者的疗效和安全性。方法采用随机、双盲、多中心研究。患者经6周筛选后符合 LDL-C≥4.14 mmol/L(160 mg/dl),<6.50 mmol/L(250 mg/dl)、TG<4.52 mmol/L(400 mg/dl)者以2:1随机接受瑞舒伐他汀10 mg/d 或阿托伐他汀10mg/d 治疗。12周后瑞舒伐他汀组 LDL-C 未达到 ATPⅢ治疗目标者,予瑞舒伐他汀20 mg 延续治疗8周。结果 304例进入随机治疗阶段,瑞舒伐他汀10 mg/d 组201例,阿托伐他汀10 mg/d 组103例。意向治疗人群290例,符合方案人群263例。瑞舒伐他汀组治疗12周后血 LDL-C 显著下降,下降幅度为45.6%,显著大于阿托伐他汀组的39.0%(P<0.001)。瑞舒伐他汀组患者 LDL-C 达标率也较阿托伐他汀组(78.0%比72.7%)有增高趋势,且在高危人群中优势更为明显(56.5%比35.0%),但差异未达到统计学意义。瑞舒伐他汀降低 TG(-22.8%)以及升高 HDL-C(+6.6%)和ApoA-1(+12.5%)的幅度与阿托伐他汀组差别无统计学意义(分别为-16.6%,+4.3%和+9.8%)。29例患者接受20 mg/d 瑞舒伐他汀延续治疗,22例完成治疗患者中10例(45.5%)LDL-C达标。研究中未发现药物相关的严重不良反应事件。结论本组研究显示瑞舒伐他汀10 mg 降低LDL-C 的疗效优于同等剂量的阿托伐他汀,治疗3个月安全性与之类似。Rosuvastatin Registration Clinical Trial Group.Cardiovascular Institute and Fu Wai Hospital,Peking Union Medical College and Chinese Academy of Medical Science,Beijing 100037,China 2007中华心血管病杂志2007,35,3:117
12Spatiotemporal variations of vegetation cover on the Chinese Loess Plateau(1981―2006):Impacts of climate changes and human activities显示文摘Spatiotemporal variations of Chinese Loess Plateau vegetation cover during 1981-2006 have been investigated using GIMMS and SPOT VGT NDVI data and the cause of vegetation cover changes has been analyzed, considering the climate changes and human activities. Vegetation cover changes on the Loess Plateau have experienced four stages as follows: (1) vegetation cover showed a continued increasing phase during 1981―1989; (2) vegetation cover changes came into a relative steady phase with small fluctuations during 1990―1998; (3) vegetation cover declined rapidly during 1999―2001; and (4) vegetation cover increased rapidly during 2002―2006. The vegetation cover changes of the Loess Plateau show a notable spatial difference. The vegetation cover has obviously increased in the Inner Mongolia and Ningxia plain along the Yellow River and the ecological rehabilitated region of Ordos Plateau, however the vegetation cover evidently decreased in the hilly and gully areas of Loess Plateau, Liupan Mountains region and the northern hillside of Qinling Mountains. The response of NDVI to climate changes varied with different vegetation types. NDVI of sandy land vegetation, grassland and cultivated land show a significant increasing trend, but forest shows a decreasing trend. The results obtained in this study show that the spatiotemporal variations of vegetation cover are the outcome of climate changes and human activities. Temperature is a control factor of the seasonal change of vegetation growth. The increased temperature makes soil drier and unfavors vegetation growth in summer, but it favors vegetation growth in spring and autumn because of a longer growing period. There is a significant correlation between vegetation cover and precipitation and thus, the change in precipitation is an important factor for vegetation variation. The improved agricultural production has resulted in an increase of NDVI in the farmland, and the implementation of large-scale vegetation construction has led to some beneficial effect in ecology.XIN ZhongBao1,2, XU JiongXin1 & ZHENG Wei1, 2 1 Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2 Graduate University of the Chinese Academy of Sciences, Beijing 100049, China 2008Science China Earth Sciences2008,51,1:112
13Value of ecosystem services in China显示文摘The function and services are the important components of the life-support system in theplanet, as well as the basic elements for sustainable development of environment and society. It is a must to evaluate it for incorporating it with the social-economic system. It is also an important approach to draw the public attention on the environmental and ecosystem conservation. In this study, the ecosystem function and services in China were estimated by employing the classification and economic parameters from Costanza et al. The type and area of terrestrial ecosystems were extracted from Vegetation Map of China (1:4 000 000), and then the distribution map of ecosystem services of China was drawn. According to our calculation, the total value of ecosystem services in China is 77 834.48×108 RMB yuan per annum. The value for terrestrial ecosystem is 56 098.46×108 yuan per annum, and that for marine ecosystem is 21 736.02×108 yuan per annum. The value of ecosystem services in China is 1.73 times biggerCHEN Zhongxin & ZHANG XinshiLaboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China Current address: Institute of Natural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China 2000Chinese Science Bulletin2000,45,10:128
14不稳定性心绞痛、急性非Q波心肌梗死不同抗栓疗法的对比研究显示文摘目的 观察不同抗栓方案对急性冠状动脉综合征心脏事件、出血风险和预后的影响。方法 本研究为前瞻性、多中心、随机、开放试验 ,入选患者随机分为静脉滴注普通肝素组和皮下注射低分子量肝素组。入选对象为不稳定性心绞痛或非Q波心肌梗死 ,入选前 4 8小时以内至少有一次心绞痛发作 ,ST段无抬高。肝素 10 0IU/kg静注 ,续 10 0 0IU/h ,维持活化的部分凝血活酶时间 (APTT)或活化的全血凝固时间 (ACT)于正常的 1 5~ 2 0倍 ,连续 7日。低分子量肝素 0 4~ 0 6ml,每日两次皮下注射 ,连续 7日。主要观察终点 :随访治疗 3 0日内发生急性心肌梗死、心脏性或非心脏性死亡和药物治疗无法控制心绞痛 ,需行急性血运重建术。住院至少 7日 ,随访至治疗后 3 0日。结果 本研究共入选符合条件的患者 4 0 2例 ,两组在性别、年龄、心血管危险因素和心绞痛发作方面差异无显著性。治疗后 7日 ,两组用药期间平均胸痛发作次数差异无显著性 ,但肝素组有更多的患者需口服硝酸甘油缓解胸痛 ;病死率在低分子量肝素组较普通肝素组低 ,两组比较P值为 0 0 62 ,复合终点事件 (死亡、心肌梗死和紧急血管重建 )在低分子量肝素组明显下降。低分子量肝素组出血事件明显少于肝素组。治疗开始后 3 0日 ,低分子量肝素组死亡和复合终点事?Clinical Collaborative Study Group of Low Molecular Weight Heparin (Correspondent: HU Dayi, XU Juntang. Beijing Red Cross Chaoyang Hospital, Beijing University of Medical Sciences, Beijing 100020, China) 2000中华心血管病杂志2000,28,1:172
15MAPK signal pathways in the regulation of cell proliferation in mammalian cells显示文摘MAPK families play an important role in complex cellular programs like proliferation, differentiation, development, transformation, and apoptosis. At least three MAPI(families have been characterized: extracellular signal-regulated kinase (ERK), Jun kinase (JNK/SAPK) and p38 MAPK. The above effects are fulfilled by regulation of cell cycle engine and other cell proliferation related proteins. In this paper we discussed their functions and cooperation with other signal pathways in regulation of cell proliferation.WEI ZHANG, Hui Tu LIU The Key Laboratory of Cell Proliferation and Regulation Biology of Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing 100875, China 2002Cell Research2002,12,1:107
16Remarks on Urban Spatial Growth Management ResearchCHEN Jinfu,Professor,Director,Teaching & Research Office on Urban Planning,Architecture and Urban Planning School,Huazhong University of Science and Technology PhD Candidate,College of Public Administration,Huazhong University of Science and Technology,Wuhan,P.R.China.REN Lijuan,Postgraduate,Architecture and Urban Planning School,Huazhong University of Science and Technology,Wuhan,P.R.China.YU Cheng,Postgraduate,Architecture and Urban Planning School,Huazhong University of Science and Technology,Wuhan,P.R.China.XU Xiaolei,Postgraduate,Architecture and Urban Planning School,Huazhong University of Science and Technology,Wuhan,P.R.China.LI Xinyan,Lecturer,Architecture and Urban Planning School,Huazhong University of Science and Technology,Wuhan,P.R.China. 2010China City Planning Review2010,19,2:180
17Clinical observation of salvianolic acid B in treatment of liver fibrosis in chronic hepatitis B显示文摘AIM: To evaluate the clinical efficacy of salvianolic acidB (SA-B) on liver fibrosis in chronic hepatitis B.METHODS: Sixty patients with definite diagnosis of liverfibrosis with hepatitis B were included in the trial.Interferon-γ (IFN-γ) was used as control drug. Thepatients took orally SA-B tablets or received muscularinjection of IFN-γ in the double blind randomized test,The complete course lasted 6 months. The histologicalchanges of liver biopsy specimen before and after thetreatment were the main evidence in evaluation, incombination with the results of contents of serum HA,LN, Ⅳ-C, P-Ⅲ-P, liver ultrasound imaging, andsymptoms and signs.RESULTS: Reverse rate of fibrotic stage was 36.67 % inSA-B group and 30.0 % in IFN-γgroup. Inflammatoryalleviating rate was 40.0 % in SA-B group and 36.67 %in IFN-γ group. The average content of HA and Ⅳ-Cwas significantly lower than that before treatment. Theabnormal rate also decreased remarkably. Overallanalysis of 4 serological fibrotic markers showedsignificant improvement in SA-B group as comparedwith the IFN-γgroup. Score of liver ultrasound imagingwas lower in SA-B group than in IFN-γgroup (HA 36.7 %vs80 %,Ⅳ-C 3.3 % vs23.2 %). Before the treatment,ALT AST activity and total bilirubin content of patientswho had regression of fibrosis after oral administrationof SA-B, were significantly lower than those of patientswho had aggravation of fibrosis after oraladministration of SA-B. IFN-γ showed certain sideeffects (fever and transient decrease of leukocytes,occurrence rates were 50 % and 3.23 %), but SA-Bshowed no side effects.CONCLUSION: SA-B could effectively reverse liverfibrosis in chronic hepatitis B. SA-B was better than IFN-γ in reduction of serum HA content, overall decrease of4 serum fibrotic markers, and decrease of ultrasoundimaging score. Liver fibrosis in chronic hepatitis B withslight liver injury was more suitable to SA-B in anti-fibrotic treatment. SA-B showed no obvious side effects.Ping Liu Yi-Yang Hu Cheng Liu Hui-Ming Xue Zhi-Qiang Xu Lie-Ming Xu Cheng-Hai Liu Hong-Tu Gu Shanghai University of Traditional Chinese Medicine,Shanghai 200032,China Da-Yuan Zhu Shanghai Institute of Metaria Medica,Chinese Academy of Sciences,Shanghai 200031,China Zhi-Qing Zhang the 4~(th) Hualyin City Hospital,Hualan City,223000,JiangSu Province,China 2002World Journal of Gastroenterology2002,8,4:85
18A 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
19METAMORPHIC 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
20Strongly peraluminous granites of Mesozoic in Eastern Nanling Range, southern China: Petrogenesis and implications for tectonics显示文摘The strongly peraluminous granites (SPGs) of Eastern Nanling Range (ENR) are a characteristic of all bearing highly aluminous minerals, such as muscovite±Al-rich biotite±tourmaline±garnet, and lack of cordierite. In respect of petrography, geochemistry, Nd isotope, and single grain zircon U-Pb dating, the representative granite bodies of them are studied. The research shows that these granites were emplaced in two stages, namely 228-225 Ma BP and J2-3 159-156 Ma BP, belonging to Indosinian and early Yanshanian periods, respectively, and they have low εNd(t) values (-10.6--11.1), high A/CNK, Rb/Sr ratios and tDM values (1887-1817 Ma), and REE's tetrad effect (TE1, 3=1.13-1.34). In comparison with related geology, petrology and chronology of granites in adjacent regions, it is suggested that Indosinian SPGs of ENR formed in the circumstance of post-collisional extension 20 Ma after the major collision of Indosinian Movement (258-243 Ma BP) in Indo-China Peninsula, and early Yanshanian SPGs formed in the background of back-arc extension setting controlled by paleo-Pacific tectonic domain, and J1, the interval of two stages, is the interim from Tethyan to Pacific tectonic domains in South China. These SPGs have similar geological and geochemical characteristics, because they all crystallized from the magma of partial melting of early Proterozoic metasedimentary rocks when the thickened crust (≤50 km) became thinning, decompression, and transmitting of water.SUN Tao, ZHOU Xinmin, CHEN Peirong, LI Huimin, ZHOU Hongying, WANG Zhicheng & SHEN Weizhou Department of Earth Sciences, Nanjing University, Nanjing 210093, China Tianjin Institute of Geology and Mineral Resources, China Geological Survey, Tianjin 300170, China 2005Science China Earth Sciences2005,48,2:78
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