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Relations between sedimentary sequence and paleoclimatic changes during last 200 ka in the southern South China Sea

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Chinese Science Bulletin 2000年第14期45卷 1334-1340页

作者： Muhong Chen Xia Tu Fan Zheng Wen Yan Xianzan Tang Jun Lu Baogui Wang Miao’an Lu Chinese Acad Sci S China Sea Inst Oceanol Open Lab Marginal Sea Geol & Paleoenvironm Guangzhou 510301 Peoples R China

Core NS-93-5 was taken from the mild slope terrace of the southern South China Sea (SCS), which has preserved the steadiness depositional record of the normal marine environment since late Quaternary. Sedimentary sequence and oxygen isotopic stratigraphy of high resolution in the near 200 ka of the southern SCS has been established. By the comparative analysis with GISP2’s ice core, the depositional record of D/O’s events 1-21 and Heinrich’s events H1-H6 in the southern SCS that reflected the quick climate change in short time scale since the last interglacial stage is revealed, which indicates that in the last 200 ka in the southern SCS and the Arctic area there was tele-connection of paleoclimate and the unstability of the Western Pacific Warm Pool. This note shows that the sedimentary layers order of this sea area classified by color identification and by oxygen isotope stratum has the very good corresponding relation. The color feature of sediment changes along with the climate and the former

关键词： southern South China Sea sedimentary sequence quick climate change D/O and Heinrich events Toba’s volcanic record.

Geometry and tectonic deformation of the seismogenic structure for the 8 August 2017 M_S 7.0 Jiuzhaigou earthquake sequence,northern Sichuan, China

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Earth and Planetary Physics 2019年第3期3卷 253-267页

作者： Feng Long GuiXi Yi SiWei Wang YuPing Qi Min Zhao Sichuan Earthquake Agency Sichuan Seistech Corporation Ltd.

To reveal the geometry of the seismogenic structure of the Aug. 8, 2017 M_S 7.0 Jiuzhaigou earthquake in northern Sichuan,data from the regional seismic network from the time of the main event to Oct. 31, 2017 were used to relocate the earthquake sequence by the tomoDD program, and the focal mechanism solutions and centroid depths of the M_L ≥ 3.5 events in the sequence were determined using the CAP waveform inversion method. Further, the segmental tectonic deformation characteristics of the seismogenic faults were analyzed preliminarily by using strain rosettes and areal strains(As). The results indicate:(1) The relocated M_S 7.0 Jiuzhaigou earthquake sequence displays a narrow ～ 38 km long NNW-SSE-trending zone between the NW-striking Tazang Fault and the nearly NSstriking Minjiang Fault, two branches of the East Kunlun Fault Zone. The spatial distribution of the sequence is narrow and deep for the southern segment, and relatively wide and shallow for the northern segment. The initial rupture depth of the mainshock is 12.5 km, the dominant depth range of the aftershock sequence is between 0 and 10 km with an average depth of 6.7 km. The mainshock epicenter is located in the middle of the aftershock region, showing a bilateral rupture behavior. The centroid depths of 32 M_L ≥ 3.5 events range from 3 to 12 km with a mean of about 7.3 km, consistent with the predominant focal depth of the whole sequence.(2) The geometric structure of the seismogenic fault on the southern section of the aftershock area(south of the mainshock) is relatively simple, with overall strike of ～150° and dip angle ～75°, but the dip angle and dip-orientation exhibit some variation along the segment. The seismogenic structure on the northern segment is more complicated; several faults, including the Minjiang Fault, may be responsible for the aftershock activities. The overall strike of this section is ～159° and dip angle is ～59°, illustrating a certain clockwise rotation and a smaller dip angle than the southern segment. The differences betw

关键词： MS 7.0 Jiuzhaigou earthquake sequence relocation focal mechanism seismogenic structure geometry tectonic deformation

sequence Divergence of Mitochondrial 12S rRNA Gene and Phylogenetic Relationship Between Rattus rattus Sladeni and Rattus rattus Hainanicus

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中山大学学报（自然科学版） 2005年第3期44卷 82-85页

作者： JIANGQing-lan HeMiao XINJing-xi OOIE.C.Vincent KWANHoi-shan CoreLab TheFirstMunicipalPeople＇sHospitalofGuangzhouGuangzhou510180China DepartmentofBiology SchoolofLifeSciencesSunYat-senUniversityGuangzhou510275China DepartmentofBiology TheChineseUniversityofHongKongNTHongKongChina

The appearance and hair color between these two subspecies Rattus rattus Sladeni and R.r. Hainanicus are similar to each other. Their most major distinctive characteristic is the length ratio of tail to body. However, this characteristic was unstable in some measuring records. In Guangdong, R.r. Hainanicus is restrictedly distributed in the west region, and R.r. Sladeni is widely distributed in the other regions of this province. In this study, we detected the sequences of mitochondrial 12S rRNA gene fragments of 9 samples from R.r. Hainanicus and R.r. Sladeni (Longmen and Hong Kong populations). These 385 nucleotide positions of 12S rRNA gene fragment include 26 variable sites and 14 parsimony-informative sites. 3 insertion/deletion sites are observed. The phylogenetic relationships among these samples were constructed by Neighbor-joining and Maximum parsimony methods. The analysis shows that R.r. Hainanicus is more closely relative to the Longmen population of R.r. Sladeni than to the Hong Kong population of R.r. Sladeni. The sequencing analysis of 12S rRNA gene fragments is not agreement on the classification of subspecies R. r. Hainanicus inferred from the morphology and geographical distribution. The morphological variation of R.r. Hainanicus should result from the natural selection, which causes local adaptation and geographic isolation.

关键词： Rattus rattus Sladeni R.r. Hainannicus mitochondrial DNA sequence divergence phylogenetic relationships

Topological algebras of infinite matrix operators between sequence spaces λ and μ

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Chinese Science Bulletin 1997年第19期42卷 1591-1593页

作者： WU CongxinDepartment of Mathematics, Harbin Institute of Technology, Harbin 150001, China Department of Mathematics Harbin Institute of Technology Harbin China

SINCE Michael (1952) published the first book about topological algebras, it has become abranch of functional analysis. Applications of topological algebras have been found in complexanalysis of several variables, differential geometry, unbounded operator and others, and alge-braic topology, k-theory and others have been applied to topological algebras (see, for exam-ple, ref.[2]). It is well known that the set of all continuous linear operators on Banach spaceconstitutes a Banach algebra, so it is obviously meaningful to study the topological algebra con-stituted by the set of all continuous linear operators on concrete topological vector space. It

关键词： topologiesl algebra sequence space infinite matrix m-convexity metrizability.

Complete nucleotide sequence and genomic organization of Periplaneta fuliginosa densonucleosis virus

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Chinese Science Bulletin 2000年第19期45卷 1782-1786页

作者： Haitao Guo Jiamin Zhang Yuanyang Hu Wuhan Univ Coll Life Sci Wuhan 430072 Peoples R China

We have cloned the replicative form of the Periplaneta fuliginosa densonucleosis virus (PfDNV) genome and determined its complete sequence. The sequence has 5 454 nucleotides (nt), the genome consists of an internal unique sequence flanked by inverted terminal repeats (201 nt). The first 122 nt at the 5’end and the terminal 122 nt at the 3’end of both plus and minus strands can fold into a typical hairpin structure. The genome contains seven major open reading frames (ORFs). The plus strand has 4 ORFs occupying the 5’half of the plus strand, whereas the others span the 5’ half of the minus strand. Two potential promoters were found at map units (m.u.) 3 and 97. Computer analysis of sequence homologies with other parvoviruses suggests that the plus strand of Pf DNV encodes very likely the nonstructural proteins and the minus strand probably encodes the structural proteins.

关键词： Perlplaneta fuliginosa densovirus nucleotide sequence genomic organization.

Analysis of the characteristic sequence of intein and revision of its motifs

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Chinese Science Bulletin 2001年第9期46卷 758-761页

作者： Jun Xie Jingfei Huang Xiufan Shi Ciquan Liu Chinese Acad Sci Kunming Inst Zool Kunming 650223 Peoples R China

Since the first intein (Sce VMA) was found in Saccharomydes cerevisiae ATPases gene in 1990, more and more inteins were identified. It is necessary to analyze the new inteins to understand the sequence charateristics of inteins. By searching protein and nucleic acid database systematically, 101 inteins were found, of which 69 inteins contain homing endonuclease motifs. We only analyze the 69 inteins since most inteins are the classic inteins with homing endonuclease motifs. We found that the distribution of these inteins is particular among species and protein. By multiple sequence alignment, some new sequence characteristics were found and the motifs described previously were revised.

关键词： intein distribution location of intein sequence charateristics.

Telomerase activity, TRAP, DNA sequence analysis

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High Technology Letters 2001年第3期7卷 8-10页

作者：金礼吉 Department of Bioengineering Dalian University of Technology Dalian 116012 China

Telomeric repeat amplification protocol (TRAP) is now a conventional assay for detecting telomerase activity. However, this method presents problems owing to tedious quantitation, radioisotopic handling. In order to alleviate these inconveniences, a novel telomerase DNA sequencing assay together with TRAP to detect human telomerase activity was developed. It was used to detect telomerase activity in Hela, HLF, MCF, K562, SMMC 7721 cells, Leukocytes and RNase pretreated or heat treated cells as control. Telomerase activity assayed by this method was positive when the number of K562 cells examined was 102,103, and 104. The telomerase activity depended on the number of K562 cells used in the assay. Telomerase activity of Rnase pretreated cells or heat treated cells, and human normal peripheral blood leukocyte(Leu) were negative. The result of this method was available within a few hours and was handled without radioisotope. Further studies should be taken to detect telomerase activity in quantitation.

关键词： Telomerase activity TRAP DNA sequence analysis

Characters of variation of LURR during the earthquake sequence of Xinjiang

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Chinese Science Bulletin 1998年第20期43卷 1752-1755页

作者： Haitao Wang Keyin Peng Yongxian Zhang Yucang Wang Xiangchu Yin Xinjiang Seismol Bur Urumqi 830011 Peoples R China State Seismol Bur Ctr Analyt & Predict Beijing 100036 Peoples R China State Seismol Bur Inst Geophys Beijing 100081 Peoples R China Chinese Acad Sci Inst Mech Lab Nonlinear Mech Beijing 100080 Peoples R China

The theory of the loading/unloading response ratio (LURR) was applied to the Jiashi earthquake sequence which occurred at the beginning of 1997 in Xinjiang, and found that, before the earthquakes with relatively high magnitudes in the sequence, the ratio showed anomalies of high values. That is to say, the LURR theory can be applied to the short_term earthquake prediction in some cases, especially in the early period after a strong earthquake, such as the forecasts for some strong earthquakes in the Jiashi sequence.

关键词： Jiashi earthquake sequence theory of loading/unloading response ratio (LURR) earthquake sequence.

Identification of selenocyst-eine insertion sequence(SECIS) element in eukaryotic selenoproteins by RNA Draw program

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Chinese Science Bulletin 2001年第14期46卷 1159-1161页

作者： XU Huibi HUANG Kaixun QU Xianghu GAO Zhonghong LIU Qiong CHEN Runsheng XUAN Zhenyu Department of Chemistry Huazhong University of Science and TechnologyWuhan 430074China Department of Protein Engineering Institute of BiophysicsChinese Academy of SciencesBeijing 100101China

The computer program RNA Draw was used to identify the secondary structures in the 3’untranslated regions (3’UTRs) of the mRNAs from 46 eukaryotic seleno-proteins among 7 species. The program found one or two possible SECIS elements in these selenoproteins. The SECIS element consists of a stem-loop or hairpin structure with three conserved sequences of AUGA-(A)AA-GA. SECIS element was not found by the RNA Draw program in randomly selected non-selenoproteins. The results showed that SECIS element is the unique character of the genes ofeukaryotic selenoproteins. Thus it is possible to use RNA Draw to search the SECIS elements in gene bank for potential new selenoproteins.

关键词： selenoprotein eukaryotes 3’ untranslated region (3’ UTR) selenocysteine insertion sequence (SECIS) RNA Draw program.