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The relation between black hole masses and Lorentz factors of the jet components in blazars

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Research in Astronomy and Astrophysics 2009年第3期9卷 293-301页

作者： Ming Zhou1,2.3 and Xin-Wu Cao1,2.1 shanghai Astronomical Observatory, Chinese Academy of Sciences, shanghai 2.0030, {2. 2.Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC, shanghai 2.0030, {2. 3 graduate school of the Chinese Academy of Sciences, Beijing 100049, {2. shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC Shanghai 200030 China graduate school of the Chinese Academy of Sciences Beijing 100049 China

We explore the relationship between black hole mass (MBH) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2.cm Survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 2.8 radio-loud AGNs, of which 146 blazars have reliable measurements of their apparent velocities of the jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A sig- nificant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components. The Eddington ratio is only weakly correlated with the min- imal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.

关键词： black hole physics — galaxies: active — galaxies: jets — galaxies: nuclei

Superconductivity of small metal grains

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2.& ZHU Shunquan1,3 1. Department of Physics, shanghai Normal University, shanghai 2.02.4, {2. 2. Department of Physics, Southwest Normal University, Chongqing 400715, {2. 3. Department of Computer and Electric Technology, shanghai Business school, shanghai 2.1400, {2. 1. Department of Physics Shanghai Normal University 200234 Shanghai China 2. Department of Physics Southwest Normal University 400715 Chongqing China 3. Department of Computer and Electric Technology Shanghai Business School 201400 Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are BCS theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

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 430077, china 2. graduate {2. of the Chinese Academy of Sciences, Beijing 100039, china 3. Unite Center for Astro-geodymics Research, Chinese Academy of Sciences, shanghai 2.0030, china 1. Institute of Geodesy and Geophysics Chinese Academy of Sciences 430077 Wuhan China 2. graduate school of the Chinese Academy of Sciences 100039 Beijing China 3. Unite Center for Astro-geodymics Research Chinese Academy of Sciences 200030 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 2.0 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

Sequence analysis of mRNA polyadenylation signals of rice genes

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Chinese Science Bulletin 2006年第9期51卷 1069-1077页

作者： LU Ying1, 2. GAO Chenxi1,2.3 & HAN Bin1,3,41. National Center for Gene Research, shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, shanghai 2.02.3, {2. 2. graduate school of the Chinese Academy of Sciences, Beijing 100039, {2. 3. Institute of Plant Physiology and Ecology, shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, shanghai 2.0032. {2. National Center for Gene Research Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200233 China graduate school of the Chinese Academy of Sciences Beijing 100039 China Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China

The formation of eukaryotic mRNAs involves the cleavage and polyadenylation of pre- mRNAs. To investigate the sequence requirement of putative polyadenylation signals (PASs), poly(A) sites and downstream elements (DUEs) in 3′-end-pro- cessing in rice, we compared expressed sequences tags (ESTs) with poly(A) extremity to full-length cDNA sequences and constructed a database of 12.69 pre- mRNA sequences in ?40―+40 nt surrounding the poly(A) sites, which were from 9953 genes. The al- ternative poly(A) sites were revealed in approxi- mately 2.% of mRNAs. Nearly 80% of pre-mRNAs showed stringent requirement of the YA (CA or UA) at poly (A) sites for polyadenylation. About 7.9% had the AAUAAA signals on ?40―?1 nt upstream of the poly(A) sites. Over 60% of mRNAs probably used the one- or two-base variants of AAUAAA hexamers as their PASs in 3′ fragments. The single-base variants of AAUGAA revealed the high frequency in 11.5% of 3′ fragments. The DUEs were detected in 90% of pre- mRNAs, especially more than half of the pre-mRNAs with multi-base variants of AAUAAA had the DUEs surrounding the poly(A) site. The location of DUE is also important for defining the cleavage site. Al- though most of the rice pre-mRNAs did not contain AAUAAA signal, the existence of downstream ele- ments ensured the efficiency of cleavage-polyade-

关键词：多聚腺苷酸序列分析 mRNA 水稻基因工程

Research on nonlinear constitutive relationship of permanent deformation in asphalt pavements

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 671-682页

作者： PENG Miaojuan1 & XU Zhihong2.1. Department of Civil Engineering,shanghai University,shanghai 2.0072.{2. 2. school of Transportation Engineering,Tongji University,shanghai 2.0092.{2. 1. Department of Civil Engineering Shanghai University Shanghai 200072 China 2. school of Transportation Engineering Tongji University Shanghai 200092 China

To predict correctly the rut depths in asphalt pavements,a new nonlinear viscoelastic-elastoplastic constitutive model of permanent deformation in asphalt pave-ments is presented. The model combines a generalized Maxwell model with an elasto-plastic one. Then from the creep theory,the linear and nonlinear constitutive equations of the generalized Maxwell model are obtained. From the nonlinear finite element method for the rutting of the asphalt pavement,the rut depths of 4 asphalt-aggregate mixtures are obtained. And the results are compared with the ones from the finite element method by SHRP and the experiments by SWK/UN. The results in this paper are better than the ones by SHRP,and agree with the ones of the experiment by SWK/UN. This shows that the nonlinear viscoelastic-elastoplastic constitutive model,which is presented in this paper for the rutting of the asphalt pavement,is effective. The properties,such as nonlinear elastic-ity,plasticity,viscoelasticity and nonlinear viscoelasticity,which affect the rutting of an asphalt pavement,can be shown in the model. And the characteristics of the permanent deformation of the asphalt pavement can be presented entirely in the model.

关键词： asphalt pavement,permanent deformation,nonlinear viscoelastic-elastoplastic constitutive relationship,generalized Maxwell model,creep compliance.

Localization of genes for lateral branch and female sex expression and construction of a molecular linkage map in cucumber (Cucumis sativus L.) with RAPD markers

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Progress in Natural Science:Materials International 2005年第2期15卷 48-53页

作者： LI Xiaozun1*, PAN Junsong1*, WANG Gang1, TIAN Libo3, SI Longting3, WU Aizhong2.* and CAI Run1**(1. Agriculture and Biology school, shanghai Jiaotong University, shanghai 2.1101, china 2. shanghai Academy of Agricultural Science, shanghai 2.1106, china 3. Horticulture school, Shenyang Agricultural University, Shenyang 110161, china) Agriculture and Biology school Shanghai Jiaotong University Shanghai 201101 China. Horticulture school Shenyang Agricultural University Shenyang 110161 China. shanghai Academy of Agricultural Science Shanghai 201106 China

A cucumber (Cucumis sativus L.) molecular linkage map, including 79 random-amplified polymorphic DNAs (RAPD) and two genes , lb for lateral branch and f for female sex expression, is constructed from a cross between a line, S52. with weak lateral growing ability and staminate from Dabieshan Mountains area in china and another line, S06, with strong lateral growing ability and gynoecious from Europe. The map contains nine linkage groups and spans 1110.0 cM with an average distance of 13.7 cM between loci. The lb locus is located in a longer linkage group LG-2.and flanked by two markers, OP-Q5-1 and OP-M-2.2. at 9.3 cM and 15.9 cM, respectively. In the meantime, the RAPD loci, OP-Q5-2.and BC151, in a short linkage group were found to flank f at 13.7 cM and 13.4 cM, respectively. The construction of RAPD map has paved a way for further study of the genes for lateral branch, female sex expression and other agronomic traits in cucumber.

关键词： cucumber (Cucumis sativus L.) lateral branch gynoecy RAPD genetic mapping

New lower bounds of classical Ramsey numbers R(6,12., R(6,14) and R(6,15)

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Chinese Science Bulletin 1998年第10期43卷 817-818页

作者： LUO Haipeng 1, SU Wenlong 2.and LI Qiao 3 1. Guangxi Academy of Sciences, Nanning 530031, china 2. Wuzhou First Middle school, Wuzhou 543002. china 3. shanghai Jiaotong University, shanghai 2.0030, china Guangxi Academy of Sciences Nanning China Wuzhou First Middle school Wuzhou China shanghai Jiaotong University Shanghai China

Three new cyclic graphs are constructed by using a computer, and the lower bounds of three Ramsey numbers obtained: R(6,12.≥2.4, R(6,14)≥2.8,R(6,15)≥338, which fill in three blanks in the table of bounds of Ram... 详细信息

关键词： Ramsey number lower bound cyclic graph.

Insulin-sensitizing effects of a novel α-methyl-α-phenoxylpropionate derivative in vitro

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Acta Pharmacologica Sinica 2007年第3期28卷 417-422页

作者： Hao-shu WU~(2.4) Juan-hong YU~(3,4) Ying-yin LI~2.Yu-she YANG~3 Qiao-jun HE~2.Yi-jia LOU~(2.5) Ru-yun JI~3 ~2.epartment of Pharmacology and Toxicology,College of Pharmaceutical Sciences,Zhejiang University,Hangzhou 310058,china ~3State Key Laboratory of Drug Research,shanghai Institute of Materia Medica,shanghai Institutes for Biological Sciences,graduate school of the Chinese Academy of Sciences,shanghai 2.12.3,china Department of Pharmacology and Toxicology College of Pharmaceutical Sciences Zhejiang University Hangzhou 310058 China Department of State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Graduate School of the Chinese Academy of Sciences Shanghai 201203 China

Aim:To examine the insulin sensitizing effects of a novel α-methyl-α-phenoxylpropionate derivative YY2. in insulin-sensitive cell ***:Theperoxisome proliferator-activated receptor γ（PPARγ）agonist bioactivities of YY2.were detected by a preadipocyte differentiation ***-PCR and Westernblotting analysis were used to detect the expression of the target gene or *** effects of YY2. on insulin-mediated glucose consumption were determined inthe HepG2.human hepatocellular carcinoma ***:YY2. could enhancethe differentiation of preadipocytes to adipocytes and upregulate the gene ex-pression of PPARγ2.as well as the protein expression of insulin receptor sub-strate-1（IRS-1）,glucose transporter-4（GLUT4）,and adiponectin（ACRP30）.Theeffects on GLUT4 and ACRP30 could be reversed by the PPARγ inhibitor ***,YY2. efficiently reduced glucose consumptions in HepG2.cells after2. h culture,and the effects were related to insulin and YY2. ***:YY2.,a potential insulin-sensitizing agent like rosiglitazone,couldenhance glucose consumption in HepG2.cells in a concentration-and insulin-dependent *** may improve the insulin resistance associated with type 2.iabetes.

关键词： YY2. peroxisome proliferator-activated receptor y insulin sensitivity glucose consumption

Progress in the detection of human genome structural variations

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Science china(Life Sciences) 2009年第6期52卷 560-567页

作者： WU XueMei1,3 & XIAO HuaSheng1,2.1 Center of Functional Genomics,Key Laboratory of System Biology,shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,shanghai 2.0031,{2. 2.National Engineering Center for Biochip at shanghai,shanghai 2.12.3,{2. 3 graduate school of the Chinese Academy of Sciences,shanghai 2.0031,{2. 1. Center of Functional Genomics Key Laboratory of System Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China 3. graduate school of the Chinese Academy of Sciences Shanghai 200031 China 2. National Engineering Center for Biochip at shanghai Shanghai 201203 China

The emerging of high-throughput and high-resolution genomic technologies led to the detection of submicroscopic variants ranging from 1 kb to 3 Mb in the human *** variants include copy number variations(CNVs),inversions,insertions,deletions and other complex rearrangements of DNA *** paper briefly reviews the commonly used technologies to discover both genomic structural variants and their potential ***,we highlight the array-based,PCR-based and sequencing-based assays,including array-based comparative genomic hybridization(aCGH),representational oligonucleotide microarray analysis(ROMA),multiplex amplifiable probe hybridization(MAPH),multiplex ligation-dependent probe amplification(MLPA),paired-end mapping(PEM),and next-generation DNA sequencing ***,we discuss the limitations and challenges of current assays and give advices on how to make the database of genomic variations more reliable.

关键词： structural variation cytogenetic microarray PCR paired end mapping(PEM) next-generation sequencing