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Paleoenvironments indicated by the fossil mammalian assemblages from red clay-loess sequence in the Chinese Loess Plateau since 8.0 Ma B.P.

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Science China Earth Sciences 2006年第5期49卷 518-530页

作者： XUE Xiangxu1,2, ZHANG Yunxiang1,2 & YUE Leping1,2 1. State Key Laboratory of Continent Dynamics (Northwest University), Institute of Cenozoic Geology and Environment, De- partment of Geology, Northwest University, Xi’an 710069, China 2. Institute of Earth Environment, State Key Laboratory of Loess and Quaternary Geology, Chinese Academy of Sciences, Xi’an 710075, China 1. State Key Laboratory of Continent Dynamics (Northwest University) Institute of Cenozoic Geology and Environment Department of Geology Northwest University Xi’an 710069 China 2. Institute of Earth Environment State Key Laboratory of Loess and Quaternary Geology Chinese Academy of Sciences Xi’an 710075 China

Information from eleven profiles of eolian earthy red silty clay and loess of the middle of the Late Miocene to Holocene age have been studied and correlated. A complete summary profile with projected isotopic ages and fossil-bearing beds has been assembled. The profile is subdivided into 12 stratigraphic units proceeding from the lower (older) to the upper (younger) one. The character of mammalian assemblages contained in each unit was analyzed and the corresponding pa- leo-climatic environments were deduced. The environmental character of each period and the change from the middle of the Late Miocene at about 8.0 Ma B.P. up to the Holocene progressed from the hot semiarid and semi-moist, warmer-moist, warm-moister of the Late Miocene. To slightly less warm moist, cool-dry, slight-warmer-moister of the Pliocene; later the cool to cold dry periods alternated frequently with the mild semiarid and semi-moist periods of the Quaternary. Vegetation progressed from the grasslands with sparse woods, wooded shrub-grasslands and subtropical forest-grasslands of the Late Miocene age to sparse grasslands and dry grasslands of the Pliocene; and to sparse grasslands, dry grasslands and tundras of the Quaternary. The climate changes in the Neogene were of low-amplitute in a generally warm-humid background. Those of the Quaternary were of higher am- plitude with a longer phase. Cool or cold dry and slightly warm semiarid and semi-moist climates al- ternated on a generally cool-dry background. The tendency since the start of the Quaternary was the change to more northern and western shift in the Loess Plateau, with progressively cooler and dryer conditions. The dramatic uplift of the Qinghai-Xizang (Tibet) Plateau and the forming and expansion of the Arctic ice sheet might be the main reasons of the more pronounced changes in the Quaternary.

关键词： paleoenvironment, mammalian fossils, eolian red clay-loess sequence, Loess Plateau.

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Genome organization and variation in the 3’-partial sequence of garlic latent virus in China

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Science China(Life Sciences) 2002年第4期45卷 441-448页

作者：陈炯郑红英陈剑平杨崇良 College of Life Sciences Zhejiang University Hangzhou 310029 China Virology Department Zhejiang Academy of Agricultural Sciences Hangzhou 310021 China

Ten different isolates of a carlavirus were detected by degenerate PCR from 12 garlic samples collected from 6 provinces in China, and the complete genome sequence of the Zhejiang isolate ZJ1 and 3′-terminal sequences of 9 other isolates were determined. The RNA genome of isolate ZJ1 consisted of 8363nts excluding the 3′-poly (A) tail, and the genome organization was similar to other carlaviruses with 6 open reading frames encoding a replicase, TGB1, TGB2, TGB3, CP and NABP respectively. sequence comparisons showed that all 10 isolates were Garlic latent virus (GarLV). The variations in the TGB2, TGB3 and NABP were more significant than those in the CP. High homology was also detected between those isolates and Shallot latent virus (ShLV). Phylogenetic analysis suggested that GarLV isolates from garlic can be divided into 4 main groups and Chinese isolates belonged to each group. This is the first reported molecular analysis of members of the genus Carlavirus in China.

关键词： garlic latent virus, nucleotide sequence, genome organization, variation.

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Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin

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Science China Earth Sciences 2006年第7期49卷 731-738页

作者： QIAO Yansong1,3, GUO Zhengtang2,1, HAO Qingzhen1, YIN Qiuzhen1, YUAN Baoyin1 & LIU Tungsheng1 1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 3. Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China 1. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 3. Institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China 2. Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China

In this study, grain-size of 507 bulk samples from the QA-I Mioceneloess-soil sequence at Qinan were analyzed, and the grain-size features are compared with those oftypical Quaternary loess and soil samples, representative lacustrine and fluvial samples. Theresults indicate that the grain-size distribution pattern of the Miocene loess is essentiallysimilar to that of Quaternary loess, but greatly differs from the lacustrine and fluvial *** layers are regularly coarser than soil layers, indicating cyclical climate changes. Mediangrain-size along the 253.1 m sequence varies from 6 to 13 μm and the > 63 μm fraction representsonly 5.3% in maximum, 0.9% in average. Long-term grain-size variations are consistent with the loessaccumulation rate at Qinan and with the eolian mass accumulation rate in the North Pacific. Thesefeatures firmly indicate an eolian origin of the studied sequence, and also reveal a coeval changesbetween the long-term changes of eolian grain-size and continental aridity in the dust sourceregions.

关键词： Qinan, Miocene loess-soil sequence, grain-size, eolian origin.

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Criteria for defining and recognizing the various orders of sequences in outcrop sequence stratigraphy

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Science China Earth Sciences 2004年第7期47卷 618-629页

作者： WANG Xunlian Faculty of Earth Sciences and Mineral Resources, China University of Geosciences, Beijing 100083, China State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, China 1. Faculty of Earth Sciences and Mineral Resources China University of Geosciences 100083 Beijing China 2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences 210008 Nanjing China

The regional distribution in different depositional facies belts is here regarded as an important criterion for defining and recognizing the various orders of sequences. The third-order sequence is possibly global in nature, which may be discerned in different depositional facies belts in one continental margin and can be correlated over long distances, sometimes even worldwide. Commonly, correlation of subsequence (fourth-order sequence with time interval of 0.51.5 Ma) is difficult in different facies belts, although some of them may also be worldwide in distribution. A subsequence should be able to discern and correlate within at least one facies belt. The higher-order sequences, including microsequence (fifth-order sequence) and minisequence (sixth-order sequence), are regional or local in distribution. They may reflect the longer and shorter Milankovitch cycles respectively. sequence and subsequence are usually recognizable in different facies belts, while microsequence and minisequence may be distinguished only in shallow marine deposits, but not in slope and basin facies deposits. A brief discussion is made on the essential conditions for correct identification of sequences, useful methods of study, and problems meriting special attention in outcrop sequence stratigraphy.

关键词： outcrop sequence stratigraphy, facies belt, sequence, subsequence, microsequence, minisequence, meter-scale cyclothem, Milankovitch cycle.

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sequence analysis for the complete proviral genome of reticuloendotheliosis virus Chinese strain HA9901

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Science China(Life Sciences) 2006年第2期49卷 149-157页

作者： WANG Yu CUI Zhizhong JIANG Shijin College of Animal Science and Veterinary Medicine Shandong Agricultural University Taian 271018 China College of Animal Science and Veterinary Medicine Shandong Agricultural University Taian 271018 China College of Animal Science and Veterinary Medicine Shandong Agricultural University Taian 271018 China

The genomic DNA extracted from chicken embryo fibroblast (CEF) infected with a Chi-nese field isolate HA9901 of reticuloendotheliosis virus (REV) was used as the template to amplify the REV proviral genomic cDNA by PCR with 6 pairs of primers according to published sequences. Six overlapping fragments were amplified, cloned into the TA vector and sequenced, including a fragment which was amplified from the circular proviral cDNA and covering both 5′- and 3′-ends. The complete sequence of the whole genome was established and analyzed with a DNAstar software. Comparisons of the sequence with two other strains demonstrated that the genomes of REV were relatively con-servative, the homogenecity for all genes or LTR fragments of the 3 strains was over 92%, no matter whether they were isolated from different species and regions in different years. But, the homology of Chinese strain HA9901 to a fowl pox virus-associated strain from Chickens was higher than that to strain SNV isolated from ducks.

关键词： reticuloendotheliosis virus, the genomic sequence, homology comparison.

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“Beijing Region” (3pter-D3S3397) of the Human Genome: Complete sequence and analysis

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Science China(Life Sciences) 2005年第4期48卷 311-329页

作者： The Chinese Human Genome Sequencing Consortium Beijing Genomics Institute Chinese Academy of Sciences Beijing 101300 China /James D. Watson Institute of Genome Sciences Zhejiang University Hangzhou 310008 China Chinese National Human Genome Center at Shanghai (CHGC) Shanghai 201203 China Chinese National Human Genome Center Beijing (CHGB) Beijing 100176 China

The goal of the Human Genome Project (HGP) is to determine a complete and high-quality sequence of the human genome. China, as one of the six member states, takes a region between 3pter and D3S3397 of the human chromosome 3 as its share of this historic project, referred as “Beijing Region”. The complete sequence of this region comprises of 17.4 megabasepairs (Mb) with an average GC content of 42% and an average recombination rate of 2.14 cM/Mb. Within Beijing Region, 122 known and 20 novel genes are identified, as well as 42607 single nucleotide polymorphisms (SNPs). Comprehensive analyses also reveal: (i) gene density and GC-content of Beijing Region are in agreement with human cytogenetic maps, i.e. G-minus bands are GC-rich and of a high gene density, whereas G-plus bands are GC-poor and of a relatively low gene density; (ii) the average recombination rate within Beijing Region is rela-tively high compared with other regions of chromosome 3, with the highest recombination rate of 6.06 cM/Mb in the subtelomeric area; (iii) it is most likely that a large gene, associated with the mammary gland, may reside in the 1.1 Mb gene-poor area near the telomere; (iv) many dis-ease-related genes are genetically mapped to Beijing Region, including those associated with cancers and metabolic syndromes. All make Beijing Region an important target for in-depth mo-lecular investigations with a purpose of medical applications.

关键词： Human Genome Project (HGP), "Beijing Region", complete sequence, genome landscape, sequence annotation.

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Immune and Genetic Algorithm Based Assembly sequence Planning

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Journal of Donghua University(English Edition) 2004年第6期21卷 38-42页

作者：杨建国李蓓智俞雷金宇松 College of Mechanical Engineering Dong Hua University Shanghai 200051professor College of Mechanical Engineering Dong Hua University Shanghai 200051

In this paper an assembly sequence planning model inspired by natural immune and genetic algorithm (ASPIG) based on the part degrees of freedom matrix (PDFM) is proposed, and a proto system — DSFAS based on the ASPIG is introduced to solve assembly sequence problem. The concept and generation of PDFM and DSFAS are also discussed. DSFAS can prevent premature convergence, and promote population diversity, and can accelerate the learning and convergence speed in behavior evolution problem.

关键词： assembly, assembly sequence, automatic planning, immune algorithm, genetic algorithm

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Depositional architecture of the Tertiary tectonic sequences and their response to foreland tectonism in the Kuqa depression, the Tarim Basin

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Science China Earth Sciences 2002年第3期45卷 250-258页

作者：林畅松肖建新刘景彦陈建强张燕梅纪云龙 1. Department of Energy Geology China University of Geosciences 100083 Beijing China

The Tertiary Kuqa depression is a foreland basin generated by flexural subsidence resulting from the southward thrusting of the southern Tianshan Mountains. Tertiary basin fills of the depression can be classified into four tectonic sequences bounded by gentle angular unconformities. The sequences are composed of two parts, the lower transgressive and the upper progradational successions, which are separated by a regional maximum transgressive surface. The development of these sequences is attributed to the foreland tectonic process from flexural subsidence caused by thrust loading to rebounded uplift due to the erosion and stress release. The generation of the angular unconformities defining the tectonic sequences has been interpreted as the result of the rebounded uplift and the following thrusting. It has been found that there is a significant difference in depositional pattern between the northeastern and the northwestern margins. The relatively strong thrusting and mountain building occurring along the northwestern margin resulted in the development of thick-bedded alluvial fan and angular unconformities. The northeastern margin, in contract, lacks thick alluvial fan accumulation due to weak thrusting. This difference is likely related to the pre-existing east-west partition of the basin basement.

关键词： tectonic sequence, depositional architecture, Tertiary Kuqa depression.

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Biostratigraphical significance of the Devonian Sinoleperditiini(Ostracoda)

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Science China Earth Sciences 2005年第10期48卷 1666-1671页

作者： WANG Shangqi PENG Jinlan Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Tribe Sinoleperditiini (Ostracoda), which is mainly distributed in South China and its adjacent areas, is a single natural group of the Leperditiidae, characterized by the development of a trailing chevron muscle scar. This tribe is known only from the Devonian and ranges through most of the Devonian. The evolutionary trends within the Sinoleperditiini have been well documented and are exemplified by changes in the trailing chevron muscle scar. The main evolutionary change is a tendency of the trailing chevron muscle scar to extend ventrally through time, as demonstrated by the increasing ratio (th/ah) of the vertical height of the trailing chevron muscle scar (th) to that of the adductor muscle scar (ah). The recent discovery of a sinoleperditiine assemblage (th/ah values available) in the middle-upper Lower Emsian Shanglun Formation allows to propose a sinoleperditiine biostratigraphical sequence for the Devonian. This sequence contains 11 assemblages (th/ah value available for each assemblage), which cover all the 7 Devonian stages and some substages. This sequence is particularly useful for correlating and dating Devonian rocks in the littoral clastic, lagoonal and restricted or semirestricted car-bonate platform facies where these ostracodes are most abundant and other fossils are un-common.

关键词： Sinoleperditiini biostratigraphical sequence, Devonian, South China.

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Three-dimensional structure of the Chinese Sacbrood bee virus

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Science China(Life Sciences) 2001年第4期44卷 443-448页

作者：张景强冯建勋梁玉尧谌东华周正洪张勤奋卢炘英 State Key Laboratory for Bio-control Zhongshan University Guangzhou 510275 China Department of Pathology and Laboratory Medicine University of Texas-Houston Medicine School Houston TX 77030 USA

The RNA of Chinese Sacbrood Bee Virus (CSBV) was purified and used as template to obtain a 1096 bp cDNA fragment by RT-PCR amplification. This DNA fragment was cloned into pGEM-T Easy Vector for sequencing. Analyses of the sequenced CSBV RNA fragment revealed a nucleotide sequence homology of 87.6% and a deduced amino-acid sequence homology of 94.6% with that of the Sacbrood Virus (SBV), indicating that CSBV is a different but highly homologous virus of SBV. The three-dimensional (3D) structure of CSBV was determined at 2.5 nm resolution by using electron cryo-microscopy (cryoEM) and computer reconstruction methods. The 3-D structure showed that the capsid has a T= 1 (or P= 3) icosahedral capsid shell with a smooth surface. There were 12 pentons at its icosahedral vertices (5-fold axes) and 132 holes penetrating the shell. The 3-D structure also revealed densities corresponding to the CSBV genome, suggesting icosahedrally-ordered RNA organization, a novel feature not previously reported for any picornavi-ruses.

关键词： Chinese Sacbrood virus (CSBV), sequence, three-dimensional structure, electron cryo-microscopy.

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