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Spectral analysis of quasi-stationary sea surface topography from GRACE mission

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Science China Earth sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2 & LU Yang1,3.1. Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 43.077, China 2. {3. school.of the chinese academy of sciences, Beijing 10003., China 3. Unite Center for Astro-geodymics Research, chinese academy of sciences, Shanghai 20003., China Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan China graduate school.of the chinese {3. of sciences Beijing China Unite Center for Astro-geodymics Research Chinese Academy of Sciences Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 200 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis

Expression of Monomeric Insulin Precursor in Pichia pastoris and Its Conversion into Monomeric B27 Lys Destripeptide Insulin by Tryptic Hydrolysis

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Acta Biochimica et Biophysica Sinica 2005年第4期37卷 234-240页

作者： Jin-Guo DING~(1,3. Jian FEI~2 Da-Fu CUI~1 You-Shang ZHANG~1 ~1Institute of Biochemistry and Cell Biology,and ~2Model Organism Research Center,Shanghai Institutes for Biologicol sciences, chinese academy of sciences,Shanghai 20003.,China ~3.4} school.of the chinese academy of sciences,Shanghai 20003.,China Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China graduate school.of the chinese {3. of sciences Shanghai 20003. China Model Organism Research Center Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China

Monomeric B27 Lys destripeptide insulin (B27 Lys DTrI) was designed and produced from itsprecursor expressed in Pichia pastoris through tryptic hydrolysis instead of the less efficient *** monomeric B27 Lys DTrI precursor (MIP) was purified from a cultured medium *** by a combination of hydrophobic,size-exclusion,and ion-exchange *** purifiedMIP was converted,by tryptic hydrolysis,to B27 Lys DTrI,which was then purified by ion-exchangechromatography to homogeneity as assessed by native gel electrophoresis,HPLC,amino acid composition,and electrospray mass-spectrometric analysis.B27 Lys DTrI exhibited superior monomeric properties insize-exclusion *** yield of MIP was 200 mg per liter of culture,and the overall yield ofpurified B27 Lys DTrI from the crude MIP was 70%.The in vivo biological activity of B27 Lys DTrI asdetermined by the mouse convulsion assay was 21 U/mg,identical to that obtained by semisynthesis.

关键词： monomeric B27 Lys destripeptide insulin tryptic hydrolysis Pichia pastoris

Cloning and Analyzing of Xenopus Mespo Promoter in Retinoic Acid Regulated Mespo Expression

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 759-764页

作者： Jin-Hu WANG Xiao-Yan DING* Institute of Biochemistry and Cell Biology,Shanghai Institutes for Biological sciences,chinese academy of sciences,graduate school.of the chinese academy of sciences,Shanghai 20003.,China Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China

During vertebrate embryogenesis,presomitic mesoderm cells enter a segmental program togenerate somite,a process termed ***,a member of the bHLH transcription factor family,plays important roles in this ***,how Mespo expression is regulated remains *** this question,we isolated a genomic DNA sequence containing 43.7 bp of Mespo 5’ flanking regionin *** assays show that this upstream sequence has transcription *** assayshows that this genomic contig is sufficient to recapitulate the dynamic stage-and tissue-specific expressionpattern of endogenous Mespo from the gastrula to the tailbud *** further mapped a 3.6 bp DNAsequence responding to retinoic acid *** results shed light on how Mespo expression is regulated,and suggest that retinoic acid signaling pathways play roles in somitogenesis through regulating Mespo.

关键词： bHLH paraxial presomitic segmental tailbud Xenopus laevis

Analysis of tandem repeats in the genome of chinese shrimp Fenneropenaeus chinensis

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chinese Science Bulletin 2005年第14期50卷 1462-1469页

作者： KONG Jie1 & GAO Huan2,3.1. Key Laboratory for Sustainable Utilization of Marine Fisheries Re- sources, Ministry of Agriculture, Yellow Sea Fisheris Research Insti- tute, chinese academy of Fishery sciences, Qingdao 266071, China 2. Institute of Oceanology, chinese academy of sciences, Qingdao 266071, China 3. the graduate school.of the chinese academy of sciences, Beijing 10003., China Key Laboratory for Sustainable Utilization of Marine Fisheries Resources Ministry of Agriculture Yellow Sea Fisheris Research Institute Chinese Academy of Fishery Sciences Qingdao China Institute of Oceanology Chinese Academy of Sciences Qingdao China The graduate school.of the chinese {3. of sciences Beijing China

Through random sequencing, we found a total of 884000 base-pairs (bp) of random genomic sequences in the genome of chinese shrimp (Fenneropenaeus chinensis). Using bio-soft Tandem Repeat Finder (TRF) software, 2159 tandem repeats were found, in which there were 1714 mi- crosatellites and 445 minisatellites, accounting for 79.4% and 20.6% of repeat sequences, respectively. The cumulative length of repeat sequences was found to be 116685 bp, ac- counting for 13.2% of the total DNA sequence; the cumula- tive length of microsatellites occupied 9.78% of the total DNA sequence, and that of minisatellites occupied 3.42%. In decreasing order, the 20 most abundant repeat sequence classes were as follows: AT (557), AC (471), AG (274), AAT (92), A (56), AAG (28), ATC (27), ATAG (27), AGG (18), ACT (15), C (11), AAC (11), ACAT (11), CAGA (10), AGAA (9), AGGG (7), CAAA (7), CGCA (6), ATAA (6), AGAGAA (6). Dinucleotide repeats, not only in the aspect of the number, but also in cumulative length, were the preponderant repeat type. There were few classes and low copy numbers of repeat units of the pentanucleotide repeat type, which included only three classes: AGAGA, GAGGC and AAAGA. The classes and copy numbers of heptanucleotide, eleven-nucleotide and thirteen-nucleotide primer-number-composed repeats were distinctly less than that of repeat types beside them.

关键词：虾遗传特性遗传基因 DNA

An Efficient High-Resolution Shock-Capturing Scheme for Multi-Dimensional Flows I. Hydrodynamics

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chinese Journal of Astronomy and Astrophysics 2006年第6期6卷 680-688页

作者： Cong Yu National Astronomical Observatories / Yunnan Astronomical Observatory, chinese academy of sciences, Kunming 650011 {3. school.of chinese academy of sciences, Beijing 100049 National Astronomical Observatories / Yunnan Astronomical Observatory Chinese Academy of Sciences Kunming 650011 graduate school.of chinese {3. of sciences Beijing 100049

Many problems at the forefront of theoretical astrophysics require a treatment of dynamical fluid behavior. We present an efficient high-resolution shock-capturing hydrodynamic scheme designed to study such phenomena. We have implemented a weighted, essentially non-oscillatory （WENO） scheme to fifth order accuracy in space, lILLE approximate Riemann solver is used for the flux computation at cell interface, which does not require spectral decomposition into characteristic waves and so is computationally friendly. For time integration we apply a third order total variation diminishing （TVD） Runge-Kutta scheme. Extensive testing and comparison with schemes that *** characteristic decomposition are carried out demonstrating the ability of our scheme to address challenging open questions in astrophysics.

关键词： accretion - hydrodynamics- method numerical - shock waves

Transformations and non-degenerate maps

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Science China Mathematics 2005年第Z1期48卷 195-205页

作者： LI Baokui & WANG Yuefei Institute of Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, Beijing 100080, China graduate school, chinese academy of sciences, Beijing 100080, China Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China graduate school Chinese Academy of Sciences Beijing China

We shall prove the equivalences of a non-degenerate circle-preserving map and a M(o)bius transformation in ^Rn, of a non-degenerate geodesic-preserving map and an isometry in Hn of a non-degenerate line-preserving map and an affine transformation in Rn. That a map is non-degenerate means that the image of the whole space under the map is not a circle, or geodesic or line respectively. These results hold without either injective or surjective, or even continuous assumptions, which are new and of a fundamental nature in geometry.

关键词： M(o)bius transformation, circle-preserving map, non-degenerate map.

Geometry of Broad Line Regions of Active Galactic Nuclei

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chinese Journal of Astronomy and Astrophysics 2008年第1期8卷 50-62页

作者： Xiao-Rong Lü1 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese academy of sciences, Beijing 100049 2 {3. school.of chinese academy of sciences, Beijing 100049 Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 graduate school.of chinese {3. of sciences Beijing 100049

It has long remained an open question as to the geometry of the broad line region （BLR） in active galactic nuclei （AGNs）. The reverberation mapping technique which measures the response of the broad emission lines to the ionizing continuum, when combined with multiwavelength continuum fitted by sophisticated accretion disks, provides a way of probing the BLR geometry. We analyze a sample of 3. AGNs, which have been monitored by the reverberation mapping campaign. In view of energy budget, the reverberation-based BH masses are found to be in agreement with those obtained by accretion disk models in two thirds of the present sample while the reverberation mapping methods underestimate the BH masses in about one third of objects, as also suggested by CoUin et al. in a recent work. We point out that there are obviously two kinds of BLR geometry, which are strongly dependent on the Eddington ratio, and separated by the value LBol/LEdd - 0.1. These results prefer a scenario of the disk and wind configuration of the BLR and identify the Eddington ratio as the physical driver regulating the wind in the BLR.

关键词： accretion, accretion disks - galaxies active - galaxies Seyfert - quasars general

Relationships between tree-ring width index and NDVI of grassland in Delingha

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chinese Science Bulletin 2006年第9期51卷 1106-1114页

作者： HE Jicheng1,3.& SHAO Xuemei1,21. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, China 2. Institute of Tibetan Plateau Research, chinese academy of sciences, Beijing 100085, China 3. graduate school.of chinese academy of sciences, Beijing 10003., China Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate school.of chinese {3. of sciences Beijing China Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China

Using five well-replicated Qilian juniper (Sabina przewalskii Kom.) tree-ring width index se- ries, monthly normalized difference vegetation index (NDVI) of grassland, and climatic data from 1982 to 2001, the relationships between tree-ring width index, NDVI of grassland, and climatic data were analyzed firstly. Then, the relationship between tree-ring width index and NDVI of grassland was explored. The re- sults showed that: (1) Temperature and precipitation in June influenced tree-ring width index and NDVI of grassland deeply in Delingha. (2) There were sig- nificant relationships between five tree-ring width index series (DLH1-DLH5) and monthly NDVI of grassland from June to September, with the most significant relationship being between tree-ring width index series and NDVI of grassland in August. (3. The PC1 (the first principal component derived from DLH1-DLH5 series) exhibited good agreement with monthly NDVI of grassland in the grass growth sea- son (from June to September) and the averaged NDVI in the growth season, which was attributed to their common responses to water-supply limit in Delingha. This study may allow an increase in studying the past dynamics of grassland in Delingha in that the variation of grassland NDVI during the last millennium has been reconstructed from PC1.

关键词：圆柏祁连山 NDVI 草原年轮宽度指数

Differential phosphorylation of p3. induced by apoptotic and anti-apoptotic stimuli in murine hepatocytes

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World Journal of Gastroenterology 2005年第9期11卷 1345-1350页

作者： Li-Xia Guo, Hong Xie, Laboratory of Biotherapy, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological sciences, chinese academy of sciences graduate school.of the chinese academy of sciences Laboratory of Biotherapy Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China.

AIM: To investigate the differential phosphorylation and activation of p3. in hepatocytes by pro-apoptotic Transforming Growth Factor-βi (TGF-β1), pro-survival factors Epidermal Growth Factor (EGF) and 12-0- tetradecanoylphorbol-13.acetate (TPA) and the potential mechanisms. METHODS: The phosphorylation and activation of p3. were determined by immunoblotting. Apoptosis was analyzed by morphological staining and observation, FACS analysis of sub-G1 content and DNA fragmentation assay. To quantitatively determine caspase activation, caspase activity assay was performed in vitro. RESULTS: TGF-β1-induced apoptosis was associated with the phosphorylation of p3., and SB202190, a specific inhibitor of p3., which was able to inhibit TGF-β1-induced caspase activation and apoptosis. TPA and EGF also blocked apoptosis induced by TGF-β1. Both of them induced the phosphorylation of p3.. The results showed SB202190 had no effect on TGF-β1-induced phosphorylation of p3., but effectively inhibited both EGF and TPA-induced phosphorylation of p3.. CONCLUSION: Pro-apoptotic TGF-β1, anti-apoptotic TPA and EGF induce the phosphorylation of p3. through different mechanisms that can be distinguished by SB202190. The data suggest that TPA and EGF-induced p3. phosphorylation is through an autophosphorylation-dependent mechanism. Since p3. phosphorylation induced by TGF-β1 plays an important role in caspase activation and apoptosis, TPA and EGF-induced p3. phosphorylation may not be requisite for their anti-apoptotic function.

关键词： p3. Apoptosis Hepatocytes