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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 200233, china 2. Graduate School of the chinese academy of sciences, beijing 100039, china 3. institute of Plant Physiology and Ecology, Shanghai institutes for Biological sciences, chinese academy of sciences, Shanghai 200032, china 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 12969 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 25% 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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Low-frequency variability of the North Equatorial Current bifurcation in the past 40 years from SODA

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Acta Oceanologica Sinica 2011年第3期30卷 14-19页

作者： MENG Qingji WANG Fan LIU Na Key Laboratory of Ocean Circulation and Waves （KLOCAW） Chinese Academy of Sciences Qingdao 266071 China Graduate School of chinese academy of sciences Beijing 100039 China National Marine Environmental Forecasting center Beijing 100081 China

The low-frequency variability of the North Equatorial Current （NEC） bifurcation during 1958 to 2001 was investigated with the Simple Ocean Data Assimilation （SODA） 2.0.2 dataset. In agreement with recent observations, the NEC bifurcation latitude （NBL） shifted northward as depth increases, from about 12.7°N near the surface to about 17.1°N at depths around 500 m for the annual average. This study reveals that the interannual variations of NBL, with five years period, mainly focused on the upper 500 m with amplitude increasing as depth increased. The NBL shifted southward in the past 40 years, which was more significant in the subsurface at more than -0.02°/a. The NBL manifests itself in the transports of NMK （NEC-Mindanao Current （MC）-Kuroshio） system in strong relationship with MC （0.7） and Kuroshio （-0.7）. The EOF analysis of meridional velocity off the Philippine coast shows that the first mode, explaining 62% of variance and 5 years period, was highly correlated with the southward shift of NBL with coefficient at about 0.75. The southward shift of NBL consists with the weakening of MC and strengthening of Kuroshio, which exhibited linear trends at -0.24Sv/a and 0.11Sv/a. Both interannual variation and trend of NBL were closely related to the variation of NMK system.

关键词： North Equatorial Current bifurcation latitude interannual variation linear trend NEC-Mindanao Current-Kuroshio system

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Molecular kinetics of cell aggregation and disaggregation under uniform shear flow:unequal-sized doublets

Molecular kinetics of cell aggregation and disaggregation un...

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2008年全国生物流变学与生物力学学术会议

作者： Changliang Fu,Mian Long(National Microgravity Laboratory and center for biomechanics and bioengineering, institute of mechanics,chinese academy of sciences,beijing 100190,china)

Shear-induced cell aggregation and disaggregation,mediated by specific receptor-ligand interactions,play important roles in many biological and biophysical *** investigations have been performed to elucidate the shear rate and shear stress dependence of cell *** existing models based on population balance equation(PBE),however,have rarely dealt with the aggregation

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Environmental Implication of Intensive Farming Practices on North china Plain

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chinese Journal of Population,Resources and Environment 2005年第3期3卷 11-20页

作者： Zhen Lin 1, Zhou Hailin 2 & Xie Gaodi 1 1 institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101 , china 2 The Administrative center for china's Agenda 21, beijing 100089, china institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China The Administrative center for china’s Agenda 21 Beijing 100089 China

The current pressure on production resources of North china Plain, such as land and water to feed the growing population, necessitates the assessment of the sustainability of farming practices. This study focuses on the sustainability of farming practices related to groundwater and soil fertility management. The assessment is based on selected site-specific key indicators and their established threshold limits. The current farming practices in the study area are clearly unsustainable. Only about 6% of the surveyed farm households practice sustainable farming. The study stresses that farming practice, which is economically sustainable, should not be promoted at the cost of environment. Holistic strategies need to be developed and implemented that aim at balanced use of inputs, which satisfy both productivity and environmental concerns.

关键词： sustainability indicators threshold values farming practices environmental implication

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A formal model of fair exchange protocols

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Science in china(Series F) 2005年第4期48卷 499-512页

作者： QING Sihan1,2,3 & LI Gaicheng1,2,3 1. Engineering Research center for Information Security Technology, institute of Software, chinese Aca- demy of sciences, beijing 100080, china 2. beijing Zhongke Ansheng Corporation of Information Technology, beijing 100080, china 3. Graduate School of the chinese academy of sciences, beijing 100039, china 1. Engineering Research center for Information Security Technology Institute of Software Chinese Academy of Sciences 100080 Beijing China 2. beijing Zhongke Ansheng Corporation of Information Technology 100080 Beijing China 3. Graduate School of the chinese academy of sciences 100039 Beijing China

Based on the study of existing fair exchange protocols, this paper sets up an accurate formal model by stepwise refinement. In the process of refinement an unreliable channel is employed to simulate an attack behavior. The model provides a novel formal definition of exchanged items, and presents the formal goals for fairness, accountability, etc., reflecting the inherent requirements for fair exchange protocols across-the-board. In order to check, prove, and design fair exchange protocols effectively and efficiently, the model puts forward a novel property of abuse-freeness which applies to all fair exchange protocols, gives a formal definition for trust strand of the third party, and presents general criteria of designing a secure and effective fair exchange protocol. Taking a typical fair exchange protocol as an example, this paper presents the analysis steps of fair exchange protocols appealing to our model. An unknown attack is uncovered. The analysis reveals the process of a complete attack, discovering deeper reasons for causing an attack. Finally, we modify the flawed protocol and the revised protocol ensures the desirable properties.

关键词： events local causal relation local temporal relation global relation exchanged item security goals.

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Determination　of　herbicides　atrazine　and　butachlor　in　soil　by　high　performance　liquid　chromatography

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Journal of Environmental sciences 1996年第4期8卷 504-506页

作者： Xu Weibing (Research center for Eco-Environmental sciences,chinese academy of sciences,beijing 100085,china) Res. Ctr. for Eco-Environ. sciences Chinese Academy of Sciences Beijing 100085 China

A Liquid Chromatographic procedure was described for simultaneous determination atrazine and butachlor in soil with a diode-array-detector(DAD).Unequivocal identification by Rt alone,however,is sometimes difficult. The UV spectra offer a viable alternative to *** distinct differences in Rt and UV of the peaks are noteworthy. UV spectra are extremely helpful and served to accurately identify the various component. Soil samples containing herbicide residues were extracted on a shaker using dichloromethane. The extractions were finally concentrated to 1 ml by a K-D concentrator then the residues were quantitated by peak height. Detection limits for atrazine and butachlor were 0.1 ppb and 0.8 ppb respectively. Fortified at 5.0 ng,10. 0 ng, and 50.0 ng levels,the recoveries of atrazine (n= 8)were 88.4%,95. 1% and 91. 6%. Fortified at 10. 0 ng,50. 0 ng and 80.0 ng levels,the recoveries of butachlor (n=8) were 89. 8%,91.2% and 87.4%,respectively.

关键词： RP-HPLC,atrazine butachlor herbicids soil.

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Treatment of black liquor from the papermaking industry by acidification and reuse

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Journal of Environmental sciences 2003年第5期15卷 697-700页

作者： YANG Wen bo, MU Huan zhen, HUANG Yan chu (Research center for Eco Environmental sciences, chinese academy of sciences, beijing 100085, china. Research center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 Chin

Two different kinds of black liquor from the papermaking industry were treated by acidification and reuse. The experimental parameters and conditions were discussed in detail. The experimental results indicated that the treatment process mentioned in this article is an effective process for the treatment of black liquor from the papermaking industry. By the treatment, the solid materials in black liquor are transferred into two by products and the other components are reused or evaporated. Thus, no wastewater except some condensation water would be discharged in pulping process and the problem of pollution of black liquor would be effectively solved.

关键词： black liquor acidification reuse lignin water reducing agent

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Plasmacytoid dendritic cells in antiviral immunity and autoimmunity

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Science china(Life sciences) 2010年第2期53卷 172-182页

作者： TANG Fei1,2,DU Qiumei1,2 & LIU Yong-Jun3 1 center for Infection and Immunity,institute of Biophysics,chinese academy of sciences,beijing 100101,china 2 Graduate University of chinese academy of sciences,beijing 100049,china 3 Department of Immunology and center for Cancer Immunology Research,University of Texas,M.D.Anderson Cancer center,Houston,Texas 77030,USA 1. center for Infection and Immunity Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Department of Immunology and Center for Cancer Immunology Research University of Texas M.D. Anderson Cancer Center Houston Texas 77030 USA

Plasmacytoid dendritic cells (pDCs) represent a unique and crucial immune cell population capable of producing large amounts of type I interferons (IFNs) in response to viral *** function of pDCs as the professional type I IFN-producing cells is linked to their selective expression of Toll-like receptor 7 (TLR7) and TLR9,which sense viral nucleic acids within the endosomal *** I IFNs produced by pDCs not only directly inhibit viral replication but also play an essential role in linking the innate and adaptive immune *** aberrant activation of pDCs by self nucleic acids through TLR signaling and the ongoing production of type I IFNs do occur in some autoimmune ***,pDC may serve as an attractive target for therapeutic manipulations of the immune system to treat viral infectious diseases and autoimmune diseases.

关键词： plasmacytoid dendritic cells type I interferon TLR7 TLR9 antiviral immunity autoimmune diseases

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Explanation of the mechanism of carcinogenesis and syntheses of anticancer agents with high selectivity

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Science china Chemistry 2006年第1期49卷 44-62页

作者： DAI Qianhuan1,2 1. center of Chemistry and bioengineering of Cancer Research, beijing Polytechnic University (Now known as beijing Univer-sity of Technology), beijing 100022, china 2. center of Environmental sciences, Peking University, beijing 100871, china 1. center of Chemistry and bioengineering of Cancer Research Beijing Polytechnic University Beijing 100022 China 2. center of Environmental sciences Peking University Beijing 100871 China

In 1979, the mechanism of chemical carcinogenesis, a challenging anddifficult scientific problem pending for a number of years, was explained by Dai Qianhuan. Themechanism named di-region theory predicted that a carcinogen always metabolizes to form a specialbi-functional alky-lating agent. This agent induces cross-linkages between the complementary basepairs in DMA and switches on initial mutageneses in genomes including point and frameshiftmutations. This, in turn, induces further deep mutageneses including the production of variouschimeric chromosomes, deletions and other aberrations found in genomes. In the end this initiatescarcinogenesis of the whole cell through the reverse transcription mechanism after a lengthyincubation period. Recently, this laboratory has verified that physical carcinogenesis, includingthe oncogenesis induced by radiation and asbestos as well as the carcinogenesis induced byendogenous factors such as estrogen or diethyl-stilbestrol switch on carcinogenesis by inducing theformation of cross-linkages between the complementary base pairs in DNA. Di-region theory has nowbeen supported by many experimental observations such as mutational spectra of various *** potential for carcinogenesis, teratogenesis, sterility and mutagenesis lumped together asgenetic toxicity appears to originate almost uniformly from the cross-linking between complementarybases, i.e. malignant cross-linking, which is in accordance with di-region theory. Other forms ofcross-linking between non-complementary bases, benign cross-linkings, show bi-functional alkylationanticancer activity but lack genetic toxicity. The predictable design and synthesis of a highselectivity anticancer agent with high efficacy and low genetic toxicity, a goal long pursued incancer chemotherapy, have been realized for the first time in this laboratory by inhibitingmalignant and heightening benign cross-linking using the principles of di-region theory. A series ofpatented new anticanc

关键词： mechanism of carcinogenesis, di-region theory, minoplatin, selectivity of anticancer agent, cross-linking between DNA bases, anticancer platinum complexes, predictive design of anticancer agent, second generation anticancer agent.

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THE DEVELOPMENT OF RAPIDLY SOLIDIFIED MICROSTRUCTURE IN SiC p/A356 COMPOSITES SUBJECTED TO LASER BEAM

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 1147-1152页

作者： K. Zhang and G.N. Chen Materials center, institute of mechanics,The chinese academy of sciences, beijing 100080, china

The present investigation is aimed to understand the microstructure evolution of SiC p/Al Si composites, i.e. particle distribution and matrix microstructure in laser processing. Microstructures of SiC p/A356 composite and the monolithic alloy are comparatively studied through laser remelting process. It is observed that the particle remains its original distribution after re solidification, indicating rejection of particles by rapid solidification interface does not occur. The presence of particles does not lead to any change in the phase constitution and phase morphology in the matrix, but instead result in a considerable change in growth direction of primary phase. The underlying mechanism is rationalized based on the interplay between the particles and solidification interface.

关键词： composites laser processing solidification

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