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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, China 2. graduate school of the Chinese Academy of Sciences,{2., China 3. Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 2.0032. China National Center for Gene Research Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China graduate school of the Chinese Academy of Sciences Beijing China Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 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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Report of Prionospio complex(Annelida:Polychaeta:Spio-nidae) from China's waters,with description of a new species

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Acta Oceanologica Sinica 2009年第1期28卷 116-127页

作者： ZHOU Jin LI Xinzheng Institute of Oceanology. Chinese Aeademy of Sciences Qingdao 266071 China graduate school Chinese Academy of Sciences Beijing 100039 China

Nine species of Prionospio complex are recorded from China＇s waters,including one new species and six newly recorded ***（Prionospio） pacifica ***.,is characterized by having first and forth pairs of branchiae pinnate,second and third pairs of apinnate,ventral crest on Setiger 9 and dorsal crests on Setigers *** kirrae（Wilson,1990）,Prionospio（Aquilaspio） convexa Imajima,1990,Prionospio（Minuspio） multibranchiata Berkeley,192.,Prionospio（Prionospio） bocki Sderstrm,192.,Prionospio（Prionospio） dubia Maciolek,1985 and Prionospio（Prionospio） paradisea Imajima,1990 are recorded for the first time from China＇s waters.

关键词： taxonomy Prionospio complex new species newly recorded species China's waters.

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Infrared Galaxies in the Nearby Universe

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Chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 643-652页

作者： Jian-Ling Wang 1 National Astronomical Observatories,Chinese Academy of Sciences,beijing 100012.China 2.graduate {2. of Chinese Academy of Sciences,beijing 100049,China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China graduate school of Chinese Academy of Sciences Beijing 100049 China

We used the Sloan Digital Sky Survey （SDSS） Data Release 5 （DR5） to study the morphological properties of 1137 nearby infrared （IR） galaxies, most of which are brighter than 15.9 mag in r-band. This sample was drawn from a cross-correlation of the Infra-Red Astronomical Satellite （IRAS） point source catalog redshift survey with DR5 at z ≤ 0.08. Based on this IR galaxy sample, we constructed five volume-limited sub-samples with IR luminosity ranging from 10^9.5 L⊙ to 10^12.⊙. By deriving the IR luminosity functions （LF） for different morphological types, we found that normal spiral galaxies are the dominant population below LIR ~ 8 ~ 10^10 L⊙; while the fraction of barred spiral galaxies increases with increasing IR luminosity and becomes dominant in spiral galaxies beyond LIR ≈ 5 × 10^10L⊙. As the IR luminosity decreases, the IR galaxies become more compact and have lower stellar masses. The analysis also shows that normal spiral galaxies give the dominant contribution to the total comoving IR energy density in the nearby universe, while, in contrast, the contribution from peculiar galaxies is only 39%.

关键词： galaxies evolution galaxies interactions galaxies starburst infrared galaxies galaxies luminosity function

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Numerical simulation of tides and tidal currents in Liaodong Bay with POM

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Progress in Natural Science:Materials International 2005年第1期 48-56页

作者： LIU Hao 1,2.*, YIN Baoshu 1, XU Yanqing 1,2.and YANG Dezhou 1,2.1. Institute of Oceanology, Chinese Academy of Sciences, Qingdao 2.6071, China 2. graduate school, Chinese Academy of Sciences,{2., China) Institute of Oceanology，Chinese Academy of Sciences，Qingdao 2.6071，China graduate school，Chinese Academy of Sciences Beijing 100039，China Institute of Oceanology，Chinese Academy of Sciences，Qingdao 2.6071，China

A three-dimensional ocean circulation model, called Princeton Ocean Model (POM), is employed to simulate tides and tidal currents in Liaodong Bay. The nested grid technique is adopted to improve the computation precision. Computed harmonic constants of m 1, M 2.tides at five tidal gauge stations and surface elevations at two oil platforms are compared with those observed, and show good agreements with them. Based on the calculated results, the co-amplitude and co-phase lag lines of m 1 and M 2.tidal constituents, the residual current field of M 2.constituent, tidal form, tidal current ellipse and the moving style of tidal current are given. It is found that diurnal tidal constituents have no amphidromic point whereas semi-diurnal constituents have one in the region of interest. Meanwhile, some meaningful results are concluded and presented, which are conducive to a thorough knowledge of the characteristics of tides and tidal currents in the Liaodong Bay.

关键词： Liaodong Bay POM harmonic constants amphidromic point tidal current ellipse.

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Land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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Science China Earth Sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2.3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5, LIU Linshan1, 2.& ZHENG Du1 1. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, China 2. graduate {2. of the Chinese Academy of Sciences, beijing 100039, China 3. College of Resources and Environment, Southwest Agricultural University, Chongqing 400716, China 4. The Ministry of Science and Technology, P. C. China, beijing 100862. China 5. Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate school of the Chinese Academy of Sciences Beijing China College of Resources and Environment Southwest Agricultural University Chongqing China The Ministry of Science and Technology P. C. China Beijing China Chengdu Institute of Biology Chinese Academy of Sciences Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2.00 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. Land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2.00, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2.00, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

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DYNAMIC CHANGES OF THE WETLAND AND ITS DRIVING FORCES IN FUJIN REGION IN SANJIANG PLAIN,CHINA

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湿地科学 2005年第3期3卷 176-182页

作者： WANG Zhi-Qiang~1,2. CHEN Ming~1,2.WANG Dan-Dan~1,2., ZHANG Bai~1,ZHANG Shu-Qing~1(1. Northeast Institute of Geography and Agricultural Ecology, the Chinese Academy of Sciences,Changchun Jilin 130012. China 2. graduate school of Chinese Academy of Sciences,{2., China ) Northeast Institute of Geography and Agricultural Ecology the Chinese Academy of SciencesChangchun Jilin 130012China graduate school of Chinese Academy of Sciences Beijing 100039China Northeast Institute of Geography and Agricultural Ecology the Chinese Academy of SciencesChangchun Jilin 130012China

Wetland is a kind of key natural resources. However, the wetlands have been shrinking rapidly in Sangjiang Plain and its functions have been degrading. These all hold back the sustainable development of human communities, and lead to great change in the land use /cover (LUCC), consequently caused global changes in climate, water cycling, etc.. Taken Fujin region as a case study, spatial and temporal dynamic processes of wetland and its driving forces were analyzed from 1954 to 2.00 in this paper. It showed that the wetlands had been reduced from 52.104 ha to 11×104 ha in areas during the nearly 50 years . The percentage of wetland areas reduced from 61.2.% to 12.39%. On the other hand, cultivated land increased from 2.×104 ha to 60×104 ha in areas. The percentage of the areas increased from 2..31% to 70.45%. Further quantitative analysis of the wetland landscape conversion characteristics and the correlation analysis between the change of wetland areas and population increase were made. The results showed that 40×104 ha wetlands had been converted to cultivated land within half of a century; the correlation between the rate of wetland loss and that of population increased is nearly -0.92.. So it was concluded that the main driving force of wetland shrinkage in Fujin region was the colonization of human being.

关键词：湿地动态变化三江平原生态系统生态环境

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Mass Spectrometric Evidence of Heparin Disaccharides for the Catalytic Characterization of A Novel Endolytic Heparinase

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 840-844页

作者： Yapeng CHAO1,3, Shaoxiang XIONG2. Xiulan CHENG1, and Shijun QIAN1* 1Institute of Microbiology, Chinese Academy of Sciences, beijing 100080, China 2.enter of Mass Spectrometry, Institute of Chemistry, Chinese Academy of Sciences, beijing 100080, China 3{2. school of the Chinese Academy of Sciences, beijing 100039, China Institute of Microbiology Chinese Academy of SciencesBeijing 100080 China graduate school of the Chinese Academy of Sciences{2. 100039 China Center of Mass Spectrometry Institute of Chemistry Chinese Academy of SciencesBeijing 100080 China

Heparinase from different sources can eliminate heparin or/and heparan sulfate into various low-molecular weight heparins with different characteristics. Porcine intestinal mucosa heparin was de- graded into a series of oligosaccharides by a novel heparinase from the species Sphingobacterium. Disaccha- ride components from the digests were separated and purified by ultrafiltration and HPLC. Five major peaks appeared as three types according to their retention time. The mass spectrometry of peak I mainly gave the non-sulfated disaccharide with the mass of 379 Da. Peak II and III were indicated as two major monosulfated disaccharides with molecular mass of 417 and 459 Da respectively. Moreover, the peak III represented an N- acetyl disaccharide. Both peak IV and V showed the same mass of 496 Da, hinting that they were disulfate- substituted disaccharides. No trisulfate-substituted disaccharides were detected in the mixture of the heparin digest though they were abundant in the heparin structure. The results revealed that the heparinase might specifically cut the sites with low sulfated domain in heparin.

关键词： electrospray ionization-mass spectrometry heparin disaccharides heparinase high perfor- mance liquid chromatography Sphingobacterium sp.

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On conformal measures for infinitely renormalizable quadratic polynomials

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Science China Mathematics 2005年第10期48卷 1411-1420页

作者： HUANG Zhiyong~1 JIANG Yunping~(2.3) & WANG Yuefei~3 1. school of Information,Renmin University of China,beijing 100872.China 2. Department of Mathematics,Queens College,City University of New York,NY 11367,USA Department of Mathematics,{2. school,City University of New York,New York,NY 10016,USA 3. Academy of Mathematics and Systems Science,Chinese Academy of Sciences,beijing 100080,China school of Information Renmin University of China Beijing China Department of Mathematics Queens College City University of New York NY USA Department of Mathematics Graduate School City University of New York New York USA Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China

We study a conformal measure for an infinitely renormalizable quadratic polynomial. We prove that the conformal measure is ergodic if the polynomial is unbranched and has complex bounds. The main technique we use in t... 详细信息

关键词： Julia set, conformal measure, three-dimensional puzzle, infinitely renormalizable quadratic polynomial.

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Dynamic learning rates algorithm for BPNN to forecast time series of dam security

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Progress in Natural Science:Materials International 2007年第12期17卷 1527-1530页

作者： Hu Daiping1, Wu Ruiming1, Lei Aizhong1 and Wang Qi2.1. Antai College of Economics & Management, Shanghai Jiaotong University, Shanghai 2.0052. China 2. graduate school, Lanzhou University, Lanzhou 730000, China) Antai College of Economics and Management Shanghai Jiaotong University Shanghai 200052 China graduate school Lanzhou University Lanzhou 730000 China

Time series data of dam security have a large number of observed values and should be forecasted accurately in time. Neural networks have the powerful approach ablilities of arbitrary functions and have been broadly utilized in many domains. In this paper, a dynamic learning rate training algorithm of back-propagation neural networks for time series forecasting is proposed and the networks with this algorithm are built to forecast time series of dam security. The application results demonostrate the efficiency of modelling and the effictiveness of forecasting.

关键词： neural network dynamic learning rate forecasting dam security.

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Discovery of submicron diamonds within kimberlite in Liaoning Province, China and its significance

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Chinese Science Bulletin 1997年第11期42卷 939-941页

作者： BAO Yanan, T. V. Dubuchick and T. D. Liabchekov1. graduate school in {2., Chinese Mining University, {2. 100083, China 2. Moscow Resources Institute of Mineral Materials, Russia 3. Resources Institute of Deposit Geology, Russian Academy of Sciences, Russia graduate school in {2. Chinese Mining University Beijing China Moscow Resources Institute of Mineral Materials Russia Resources Institute of Deposit Geology Russian Academy of Sciences Russia

ALTHOUGH a lot of research work on diamond mineralogy has already been done,the formationand development of diamond leave much to be *** have done some researches onthe diamond samples with obvious crystal-growing cha... 详细信息

关键词： submicron diamond lath-shape aggregative parent material.

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