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Sequence analysis of mRNA polyadenylation signals of rice genes

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 10003.,{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

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Regional differences and determinants of built-up area expansion in china

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Science china Earth Sciences 2007年第12期50卷 1835-1843页

作者： HUANG JiKun1,2.ZHU LiFen3,1 & DENG XiangZheng1,2.1 center for Chinese Agricultural Policy,Chinese Academy of Sciences,beijing 100101,{2. 2.Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,beijing 100101,{2. 3 Research center of the Economy of the Upper Reaches of the Yangtze River,Chongqing Technology and Business University,Chongqing 400067,{2. 1. center for Chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China 2. Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 3. Research center of the Economy of the Upper Reaches of the Yangtze River Chongqing Technology and Business University Chongqing 400067 China

Based on remote sensing data on land use provided by the Chinese Academy of Sciences and socio-economic data collected by the authors,this paper analyzes the trends and regional differences in built-up area(BUA) expansion in china from the late 1980s to 2.00,and empirically estimates the major determinants of BUA expansion in different regions in 1996―*** 1989―2.00,although china's overall BUA expansion accelerated,the trends differed significantly among *** expansion in the central and western regions accelerated significantly,but it slowed down considerably in the east-ern *** estimation results from our econometric {2. reveal that BUA expansion in the eastern region reached a period when economic growth had no further significant impact on per capita BUA,the land utilization in this region has become more intensive with further expansion of the *** the central and western regions,the BUA has expanded remarkably due to the relatively more flexible land development policies and the relatively cheap land ***,as the econ-omy continues to grow rapidly,policies relating to BUA expansion and cultivated land reductions may face more serious challenges in the central and western regions.

关键词： built-up area, land use, regional difference, determinants, china

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Improving the accuracy of image-based forest fire recognition and spatial positioning

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Science china(Technological Sciences) 2010年第S1期53卷 184-190页

作者： JIANG LiLi 1,QI QingWen 1,ZHANG An 1,GUO ChaoHui 2.& CHENG Xi 1,3 1 Institute of Geographical Sciences and Natural Resources Research,Chinese Academy of Sciences,beijing 100101,china 2.2. center for Resources Satellite Data and Applications,beijing 100094,china 3Graduate University of Chinese Academy of Sciences,beijing 100049,china Chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China china Ctr Resources Satellite Data & Applicat Beijing 100094 Peoples R China Chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

Forest fires are frequent natural *** is necessary to explore advanced means to monitor,recognize and locate forest fires so as to establish a scientific system for the early detection,real-time positioning and quick fighting of forest *** paper mainly expounds methods and algorithms for improving accuracy and removing uncertainty in image-based forest fire recognition and spatial ***,we discuss a method of forest fire recognition in visible-light *** are four aspects to improve accuracy and remove uncertainty in fire recognition:(1)eliminating factors of interference such as road and sky with high brightness,red leaves,other colored objects and objects that are lit up at night,(2.excluding imaging for specific periods and azimuth angles for which interference phenomena repeatedly occur,(3)improving the thresholding method for determining the flame border in image processing by adjusting the threshold to the season,weather and region,and (4)integrating the visible-light image method with infrared image ***,we examine infrared-image-based methods and approaches of improving the accuracy of forest fire recognition by combining the spectrum threshold with an object feature value such as the normalized difference vegetation index and excluding factors of disturbance such as interference signals,extreme weather and high-temperature ***,a method of visible analysis to enhance the accuracy of forest fire positioning is examined and realized;the method includes decreasing the visual angle,selecting central points,selecting the largest spots,and judging the selection of fire spots according to the central *** studies are examined and the results are found to be satisfactory.

关键词： forest fire monitoring spatial positioning accuracy improvement

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The relationship between sea surface temperature anomalies in the North Atlantic and summer monsoon in South Asia

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Acta Oceanologica Sinica 1991年第4期10卷 555-564页

作者： Song Jiaxi national Research center for Marine Environment Forecasts, {2. 100081, china

Having been calculated and analysed, it is found in this research paper that there exist a close lag relationship between sea surface temperature (SST) change in the north of the North Atlantic and height change at 500 hPa level in South Asia. In this paper, it is focused on the analysis of physical processes of the relation between SST and height and their effect on summer monsoon in South Asia.

关键词： over

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Inconsistency between WMAP data and released map

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Chinese Science Bulletin 2010年第10期55卷 907-909页

作者： LIU Hao1 & LI TiPei1,2.3 1 Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,Chinese Academy of Sciences,beijing 100049,china 2.Department of Physics & {2. for Astrophysics,Tsinghua University,beijing 100084,china 3 Department of Engineering Physics & {2. for Astrophysics,Tsinghua University,beijing 100084,china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China Department of Physics & center for Astrophysics Tsinghua University Beijing China Department of Engineering Physics & center for Astrophysics Tsinghua University Beijing China

A remarkable inconsistency between the calibrated differential time-ordered data (TOD) of the Wilkinson Microwave Anisotropy Probe (WMAP) mission,which is the input for map-making,and the cosmic microwave background (CMB) temperature maps published by the WMAP team is revealed,indicating that there must exist a serious problem in the map making routine of the WMAP *** inconsistency is easy to be confirmed without the use of WMAP map-making *** view of the importance of this issue for cosmology study,we invite readers to check it by themselves.

关键词：威尔金森微波各向异性探测器 WMAP 地图制作宇宙微波背景有序数据制作软件 TOD CMB

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Systematic distortion in cosmic microwave background maps

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Science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 804-808页

作者： LIU Hao 1,3 &LI TiPei 1,2.1Key Laboratory of Particle Astrophysics,Institute of High Energy Physics,Chinese Academy of Sciences,beijing 100049,china 2.2. for Astrophysics,Tsinghua University,beijing 100084,china 3 Graduate University of Chinese Academy of Sciences,beijing 100049,china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China center for Astrophysics Tsinghua University Beijing 100084 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

To minimize instrumentally the induced systematic errors,cosmic microwave background(CMB)anisotropy experiments measure temperature differences across the sky using pairs of horn antennas, temperature map is recovered from temperature difference obtained in sky survey through a map-making *** inspect and calibrate residual systematic errors in the recovered temperature maps is important as most previous studies of cosmology are based on these *** analyzing pixel-ring coupling and latitude dependence of CMB temperatures,we find notable systematic devia- tion from CMB Gaussianity in released Wilkinson Microwave Anisotropy Probe(WMAP)*** detected deviation cannot be explained by the best-fit LCDM cosmological model at a confidence level above 99%and cannot be ignored for a precision cosmology study.

关键词： cosmology cosmic microwave background methods data analysis

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Abnormal high pressure in Kuqa foreland thrust belt of Tarim basin: Origin and impacts on hydrocarbon accumulation

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Progress in Natural Science:Materials International 2006年第12期16卷 1307-1314页

作者： ZENG Lianbo~1** and LIU Benming~ 1,2.(1. Key Laboratory of Hydrocarbon Accumulation in china Petroleum University, Ministry of Education, beijing 102.49, china 2. The Institute of Oil and Gas Exploration and Development, Tarim Oilfield Company, Petrochina Company Limited, Korla 841000, china) [a]Ministry of Education Key Laboratory of Hydrocarbon Accumulation in China Petroleum University Beijing China [b]The Institute of Oil and Gas Exploration and Development Tarim Oilfield Company PetroChina Company Limited Korla China

Following analyses of the abnormal high pressure distribution characteristics, based on the geological characteristics, tectonic stress field and physical simulation, we investigated the formation mechanisms of abnormal high pressure and its impacts on hydrocarbon accumulation in the Kuqa foreland thrust belt. The abnormal high pressure appears at the bottom of the Paleogene and obviously exists in the Triassic and Jurassic. However, the pressure coefficient in the Triassic and Jurassic is lower than that in the Cretaceous and at the bottom of the Paleogene. Horizontally, the abnormal high pressure distribution is characterized by E-W orientation zoning. The maximum pressure coefficient lies in the Kelasu-Dongqiu-Dina tectonic zones in the center of the Kuqa foreland thrust belt and decreases away from the tectonic zones. The formation of abnormal high pressure was mainly related with the intense tectonic compression in the Early Pleistocene time, and tectonic uplifting, undercompaction and hydrocarbon generation were secondary factors contributing to abnormal high pressure. Under the rapid and intense tectonic compression in the Early Pleistocene, the rock framework firstly undertook 1/4 of the compression stress and the other was borne by the pore fluids. Due to the presence of great seal of gypsum-salt or gypsum-mudstone beds in the Paleogene, the pressure of pore fluids increased rapidly and led to the abnormal high pressure in the Kuqa foreland thrust belt. The abnormal high pressure has important impacts on hydrocarbon accumulation. It is one of the necessary conditions for formation of large oil and gas fields in the Kuqa foreland thrust belt.

关键词： abnormal high pressure formation mechanism oil and gas reservoir Kuqa foreland thrust belt Tarim basin.

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An analysis of the wide area differential method of geostationary orbit satellites

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Science china(Physics,Mechanics & Astronomy) 2009年第2期52卷 310-314页

作者： CAI ChengLin1,2.3?, LI XiaoHui1 & WU HaiTao1 1 national Time Service center, Chinese Academy of Sciences, Lintong 710600,{2. 2.Hunan Institute of Humanities, Science and Technology, Loudi 417000,{2. 3 Graduate University of Chinese Academy of Sciences, beijing 100049,{2. 1. national Time Service center Chinese Academy of Sciences Lintong 710600 China 2. Hunan Institute of Humanities Science and Technology Loudi 417000 China 3. Graduate University of Chinese Academy of Sciences Beijing 100049 China

This work aims to obtain a wide area differential method for geostationary orbit (GEO) constellation. A comparison between the dilution of precision (DOP) of four-dimensional (4D) calculation including sa- tellite clock errors and ephemeris errors and that of three-dimensional (3D) calculation only including ephemeris errors with the inverse positioning theory of GPS shows the conclusion that all the 3D PDOPs are greatly reduced. Based on this, a basic idea of correcting satellite clock errors and ephem- eris errors apart is put forward, and moreover, a specific method of separation is proposed. Satellite clock errors are separated in a master station with time synchronization, and all the remaining pseu- do-range errors after the satellite clock errors have been deducted are used to work out ephemeris corrections of all GEO satellites. By a comparative analysis of user positioning accuracy before and after differential, the wide area differential method is verified to be quite valid for GEO constellation.

关键词： geostationary orbitsatellite dilution of precision satellite ephemeris errors satellite clock errors wide area differential method

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A comparison analysis between developed and undeveloped depressions over the South china Sea

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Acta Oceanologica Sinica 1989年第2期8卷 199-208页

作者： Liang Biqi Zhang Qiuqing Department of Atmospheric Sciences, Zhongshan University, Guangzhou, china national Research {2. for Marine Environment Forcasts, beijing, china Dept. of Atmospheric Sciences Zhangshan Univ. Guangzhou China. China

-- In this paper, by using two sets of composite data of developed and undeveloped depressions over the South china Sea, we analyze and compare the dynamic structures, the heating fields and the vorticity budget residuals of two different types of depressions. Our conclusions are as follows:The two types of depressions are similar in thermodynamical and dynamical structures. The main differ ences are : in the high layer of developed depression there is a divergence field, with a center near the zero line of vertical wind shear, and over undeveloped depression, the divergence field is weaker and the vertical wind at its center is greater than 5 m s-1. The thermodynamical field of the former is asymmetrical and that of the latter is quasi - symmetrical. As far as the dynamics structure is concerned, the convergence in the lower layer and the difference of divergence between the upper and lower layers of developed depression is three tmies larger than that of undeveloped depression. The upward motion and heating field at the center of developed depression is also stronger than that of undeveloped *** vorticity budget of the two types of depressions is mainly determined by the divergence term, the vorticity advection term and the vertical transport term. The residual term is also *** principal contribution comes from the divergence term . This is more significant for developed depression than for undeveloped depression.

关键词： over A comparison analysis between developed and undeveloped depressions over the South china Sea

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Selective support of a mouse thymus epithelial cell line(MTEC1)to the viability and proliferation of CD4~+CD8~-,CD4~-CD8~-,and CD4~+CD8~+thymocytes in vitro

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Cell Research 1992年第2期2卷 183-193页

作者： CHEN WEIFENG, QILING SUN, AND JAPING TAO Department of Immunology,center of Calculation and analysis, {2. Medical University, {2. 100083, china center of Calculation and analysis Beijing Medical University Beijing 100083 China

The MTEC1 cell line,established in our laboratory,isa normal epithelial cell line derived from thymus medulla ofBalb/c mice and these cells constitutively produce *** selection of thymic microenvironment on de-veloping T cells was investigated in an in vitro ***-separated fresh thymocytes from Balb/c mice were cocul-tured with MTEC1 cells or/and MTEC1-SN,then,the via-bility,proliferation and phenotypes of cultured thymocyteswere *** any exogenous stimulus,bothMTEC1 cells and MTEC1-SN were able to maintain the vi-ability of thymocytes,while only the MTEC1 cells,not theMTEC1-SN,could directly activate thymocytes to exhibitmoderate proliferation,indicating that the proliferative sig-nal is delivered through cell surface interactions of MTEC1cells and *** analysis on FACS of viablethymocytes after coculture revealed that MTEC1 cellsPreferentially activate the subsets of CD4~+ CD8~-,CD4~+CD8~+ and CD4~- CD8~- thymocytes;whereas MTEC1-SNpreferentially maintained the viability of CD4~+ CD8~- andCD4~- CD8~+ thymocyte subsets. For the Con A-activated thymocytes,both MTEC1cells and MTEC1-SN grovided accessory signal(s) to signifi-cantly increase the number of viable cells and to markedlyenhance the proliferation of thymocytes with virtuallyequal potency,phenotyped as CD4~+ CD8~-,CD4~- CD8~+,andCD4~- CD8~- *** summary,MTEC1 cells displayedselective support to the different thymocyte subsets,and theselectivity is dependent on the status of thymocytes.

关键词： thymic selection thymic epithelial cells thymocyte subsets cytokines flow cytometry.

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