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Overview of HBV whole genome data in public repositories and the chinese HBV reference sequences

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Progress in Natural Science:Materials International 2008年第1期18卷 13-20页

作者： Guanghua Wu a,b, Huiguo Ding c, Changqing Zeng b,* a graduate School of chinese {2. of sciences, beijing 1.0049, china b beijing Institute of Genomics, chinese {2. of sciences, beijing 101300, china c beijing Youan Hospital, Capital Medical university, beijing 100069, china graduate School of chinese {2. of sciences Beijing 100049 China beijing Institute of Genomics Chinese Academy of Sciences Beijing 101300 China beijing Youan Hospital Capital Medical University Beijing 100069 China

The number of Hepatitis B virus (HBV) whole genomic sequences in public nucleotide databases (GenBank, EMBL, and DDBJ) had reached 866 by January 1, 2.07. Coming from 46 countries and regions, these sequences were categorized as eight genotypes (A–H). With the statistical and phylogenetic analysis on all available complete genomic data of HBV, we here present an overview of HBV sequences in public databases. From all registered 2.9 HBV genomes in chinese regions as well as 59 sequencing data from our research group, we report the establishment of reference sequences of HBV strains prevailing in china. These analyses provide clues for the effects of HBV genotypes in host clinical progressions, geographic distribution of the infection, and the viral evolutionary history. Moreover, the viral sequence reference would be helpful in the identiffcation of various HBV mutations. Based on the analysis of various public databases, we suggest that the chinese HBV database with the clinical information should be constructed.

关键词： Public databases HBV genomic sequences Genotype Subtype chinese reference sequences

Boundedness of solutions and existence of invariant tori for generalized pendulum type equation

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chinese Science Bulletin 1997年第20期42卷 1673-1675页

作者： HUANG Hai and YUAN Rong1. Institute of Mathematics, chinese academy of {2., beijing 100080, china 2. Department of Mathematics, beijing Normal university, beijing 100875, china Institute of Mathematics Chinese Academy of Sciences Beijing China Department of Mathematics Beijing Normal University Beijing China

MOTIVATED by various significant applications to non-Newtonian fluid theory, diffusion offlows in porous media, nonlinear elasticity, and theory of capillary surfaces, several authors(see refs.[1,2. and references cited therein ) have recently studied the existence of periodicsolutions and other properties for the following differential equation:

关键词： boundeduess of solutions invariant tori quasiperlodic solutions Moser’s small twist theorem.

An efficient chiral synthesis of (R)-N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl]-butanamide with high enantioselectivity

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Science china Chemistry 2009年第8期52卷 1216-1219页

作者： WANG NaiXing1,2.& TANG XinLiang1,3 1 Technical Institute of Physics and Chemistry,chinese academy of {2.,beijing 100080,china 2.College of Chemistry and Chemical Engineering,graduate university of chinese academy of {2.,beijing 1.0049,china 3 School of Chemical Engineering and Environment,beijing Institute of Technology,beijing 100081,china 1. Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China 2. College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China 3. School of Chemical Engineering and Environment Beijing Institute of Technology Beijing 100081 China

R-Enantiomer of the β-receptor antagonist N-[3-acetyl-4-(2.hydroxy-3-isopropylamino-propoxy)phenyl] butanamide with high enantioselectivity was synthesized from cheap starting materials and enantiopure chiral reagent through an efficient,convenient and practical synthetic *** product was detected by 1H NMR,13C NMR,and MS,and the enatiomeric excess was determined by chiral HPLC analysis using a chiracel AD-H column.

关键词： chiral synthesis enantioselectivity enatiomeric excess chiral HPLC analysis

Artificial coordinating field and its application to motion planning of robots in uncertain dynamic environments

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Science china(Technological sciences) 2004年第5期47卷 577-594页

作者： JING Xingjian1, 2. WANG Yuechao1 & TAN Dalong1 1. Robotics Laboratory, Shenyang Institute of Automation, chinese academy of {2., Shenyang 110016, china 2. graduate School, chinese academy of {2., beijing 100039, china Correspondence should be addressed to Jing Xingjian 1. Robotics Laboratory Shenyang Institute of Automation Chinese Academy of Sciences 10016 Shenyang China 2. graduate School Chinese Academy of Sciences 10039 Beijing China

Artificial coordinating fields (ACF) are proposed to deal with the motion planning problems of mobile robots in uncertain dynamic environments. An ACF around an obstacle can generate two orthogonal force vectors to a robot: one is called the coordinating force vector which is purposively designed in this paper, and the other is the repulsive force vector which is the same as that in a conventional artificial potential field. The ACF is designed according to the updated motion purpose and the relative states of the robot with respect to its local environment, and it also satisfies the robot’s dynamic constraints. The direction of the coordinating force can be determiend on line according to an optimal evaluation function. The ACF can effectively remove the local minima, and reduce the oscillation of the planned trajectory between multiple obstacles. Only local knowledge of the environments is needed in the ACF-based motion planning. The properties of the ACF such as controllability, adaptability, safety and reachability are studied and discussed in detail in this paper. Theoretical analysis and simulations are given to illustrate our main results.

关键词： artificial coordinating fields, artificial potential fields, mobile robots, motion planning, uncertain dynamic environments.

ORDER RESULTS FOR ALGEBRAICALLY STABLEMONO-IMPLICIT RUNGE-KUTTA METHODS

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Journal of Computational Mathematics 1999年第6期17卷 639-644页

作者： Ai-guo Xiao(1. Department of Mathematics, Xiangtan university, Xiangtan 411105, china2. ICMSEC, {2. academy of sciences, beijing 10080, china) Xiangtan Univ Dept Math Poona 411005 Maharashtra India chinese Acad Sci ICMSEC Beijing 100080 Peoples R China

It is well known that mono-implicit Runge-Kutta methods have been applied in the efficient numerical solution of initial or boundary value problems of ordinary differential equations. Burrage (1994) has shown that the order of an s-stage monoimplicit Runge-Kutta method is at most s+1 and the stage order is at most 3. In this paper, it is shown that the order of an s-stage mono-implicit Runge-Kutta method being algebraically stable is at most min((s) over tilde, 4), and the stage order together with the optimal B-convergence order is at most min(s, 2., where [GRAPHICS]

关键词： ordinary differential equations mono-implicit Runge-Kutta methods order algebraical stability

Cloning and expression of putative ethylene receptor genes in soybean plant

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Progress in Natural Science:Materials International 2007年第10期17卷 1152-1160页

作者： Xie Zongming1,2.3, Lei Gang1,2. Wuriyanghan Hada1,2. Tian Aiguo1, Zhang Jinsong1 and Chen Shouyi1(1. National Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, chinese academy of {2., beijing 100101, china 2. graduate School of chinese academy of {2., beijing 100039, china 3. Xinjiang academy of Agricultural and Reclamation Science, Shihezi 832.00, china) National Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China graduate School of chinese {2. of sciences Beijing 100039 China Xinjiang academy of Agricultural and Reclamation Science Shihezi 832000 China

Ethylene plays important roles in plant growth, development, and stress responses, and ethylene receptors have been identified and studied extensively in various plant species. Here we report the cloning of four ethylene receptor genes from soybean, i.e. GmETR1, GmERS1, GmETR2.and GmEIN4. Construction of the phylogenic tree showed that GmETR1 and GmERS1 belong to subfamily I whereas GmETR2.and GmEIN4 belong to subfamily II. The four ethylene receptor genes showed different tissue-specific expression patterns in roots, stems, leaves, cotyledons, flowers, pods and seeds of soybean. These genes were differentially regulated by various abiotic stresses and plant hormones. The possible roles of the four genes in soybean plant were also discussed.

关键词： abiotic stress expression analysis ethylene receptor plant hormone soybean.

Suprathermal particle events observed by WIND spacecraft in interplanetary space during 1995―1999 and their classification

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Science china(Technological sciences) 2008年第9期51卷 1542-1553页

作者： SUN LingPeng1,2. WU DeJin1 & WANG DeYu1 1 Purple Mountain Observatory, chinese academy of {2., Nanjing 2.0008, china 2.graduate School of chinese academy of {2., beijing 1.0049, china Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China graduate School of chinese {2. of sciences Beijing 100049 China

Fifty-five suprathermal particle events were selected from WIND observations between 1995 and 1999. Based on systematic analysis on the observational characteristics of these events a two-parameter (the rising time and the flux ratio of electrons to protons in each event) classification method was proposed to classify these events. The three clas-sified classes are (1) impulsive electron events with the flux ratio of electrons to protons being bigger than 1 and rising time being shorter than 2.0 min, (2. impulsive proton events with the flux ratio being smaller than 1 and rising time being shorter than 2.0 min, and (3) gradual proton events with the flux ratio being smaller than 1 and the rising time being longer than 2.0 min. In the past, "impulsive solar electron events" were under in-tense research. However, because the selection standards of their velocity dispersions or pitch-angle distributions were inadequate, statistical surveys of selected events were dif-ferent from each other and even some conclusions were not consistent with the theory, for example, the relation of type-III solar radio bursts to the "impulsive solar electron events". The first class of impulsive electron events are associated with type-III radio bursts and with clear velocity dispersions; therefore they ought to originate from the Sun. The second class of the events, which have short continuance time and usually are not associated with type-III radio bursts and without velocity dispersion, are still far away from inter-planetary shocks and most of them do not one-to-one correspond to corrotating interact-ing regions (CIRs); such events are possible results of local interplanetary magnetic field reconnection or electromagnetic disturbances. Finally, about 2.3 gradual proton events of the third class occur with interplanetary shocks, the delay times of which are almost equal to the rising time. Some of these events can be understood as particle accelerations by shocks.

关键词： suprathermal particles solar wind plasma solar eruptive activity interplanetary active regions

Antisense expression of a rice cellular apoptosis susceptibility gene (OsCAS} alters the height of transgenic rice

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Progress in Natural Science:Materials International 2007年第1期17卷 39-43页

作者： XU Chunxiao and HE Chaozu ( National Key Laboratory of Plant Genomics, Institute of Microbiology, chinese academy of {2., beijing 100080, china graduate university of chinese academy of {2., beijing 100039, china Shenzhen Laboratory of Superhybrid Rice Research, graduate School at Shenzhen, Tsinghua university, Shenzhen 518055, china) [a]National Key Laboratory of Plant Genomics Institute of Microbiology Chinese Academy of Sciences Beijing China [b]graduate university of {2. academy of sciences Beijing China

Cellular apoptosis susceptibility (CAS) gene plays important roles in mitosis, development and export of importin a from the nucleus, but its function in plant is unknown. In this study, a rice CAS ortholog (OsCAS), which encodes a predicted protein of 983 amino acids with 62. similarity to human CAS, was identified. DNA gel blot analysis revealed a single copy of OsCAS in the rice genome. A 973 bp fragment at the 3' end of OsCAS cDNA was cloned from rice cDNA library and transferred into rice in the antisense direction under the control of CaMV 35S promoter via Agrobacterium-mediated transformation method, 105 transgenic lines were obtained. Expression of OsCAS was suppressed in the antisense transgenic lines as revealed by semi-quantitative RT-PCR. The antisense transgenic lines showed dwarf phenotypes. The results indicated that OsCAS was involved in culm development of rice.

关键词： antisense dwarf ortholog OsCAS rice.

Application of three-dimensional discrete element face-to-face contact model with fissure water pressure to stability analysis of landslide in Panluo iron mine

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Science china(Technological sciences) 2005年第z1期48卷 146-156页

作者： ZHANG Lei1,2. WEI Zuoan1, LIU Xiaoyu1 & LI Shihai1 1.Institute of Mechanics, chinese academy of {2., beijing 100080, china 2.graduate School, chinese academy of {2., beijing 100060, china chinese Acad Sci Inst Mech Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100060 Peoples R China

Three-dimensional discrete element face-to-face contact model with fissure water pressure is established in this paper and the model is used to simulate three-stage process of landslide under fissure water pressure in the opencast mine, according to the actual state of landslide in Panluo iron mine where landslide happened in 1990 and was fathered in 1999. The calculation results show that fissure water pressure on the sliding surface is the main reason causing landslide and the local soft interlayer weakens the stability of slope. If the discrete element method adopts the same assumption as the limit equilibrium method, the results of two methods are in good agreement; while if the assumption is not adopted in the discrete element method, the critical φ numerically calculated is less than the one calculated by use of the limit equilibrium method for the sameC. Thus, from an engineering point of view, the result from the discrete element model simulation is safer and has more widely application since the discrete element model takes into account the effect of rock mass structures.

关键词： face-to-facecontactmodel, fissure water pressure, three-dimensional discrete element method,landslide.