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Molecular phylogeny of Pneumocystis based on 5.8S rRNA gene and the internal transcribed spacers of rRNA gene sequences

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science china(Life sciences) 2008年第5期51卷 445-452页

作者： LI ZiHui1,2, FENG XianMin1, LU SiQi1, ZHANG Fan1, WANG FengYun1 & HUANG Song1 1 Department of Pathogenic Biology, Capital Medical University, beijing 100069, china 2 beijing Tuberculosis and Thoracic Tumor Research Institute, beijing 101100, china 1. Department of Pathogenic Biology Capital Medical University Beijing 100069 China 2. beijing Tuberculosis and Thoracic Tumor Research Institute Beijing 101100 China

To clarify the phylogenetic relationships and species status of Pneumocystis, the 5.8S rRNA gene and the internal transcribed spacers (ITS, 1 and 2) of Pneumocystis rRNA derived from rat, gerbil and human were amplified, cloned and sequenced. The genetic distance matrix of six Pneumocystis species compared with other fungi like Taphrina and Saccharomyces indicated that the Pneumocystis genus contained multiple species including Pneumocystis from gerbil. The phylogenetic tree also showed that Pneumocystis from human and monkey formed one group and four rodent Pneumocystis formed another group. Among the four members, Pneumocystis wakefieldiae was most closely related to Pneumocystis murina and Pneumocystis carinii, and was least related to gerbil Pneumocystis.

关键词： Pneumocystis phylogeny 5.8S rRNA gene internal transcribed spacers

A NEW EXPRESSION OF X-RAY DEPTH DISTRIBUTION FUNCTION φ(pz) FOR QUANTITATIVE EDS

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电子显微学报 1991年第2期 199-200页

作者： ZHANG Renji(Tsinghua university, beijing, china)WU Ziqin(University of science and Technology of china, Hefei, china)

In our direct standardless quantitative analysis program forEDS(1,2), the X-ray depth distribution function Φ(ρz) is based onthe improved "full diffusion" model of the electron scattering andis a stepped distribution function. From this distribution function,a quantitative relationship between the constituents of thesample and the intensities of the characteristic X-rays has beenestablished directly, and the standard samples are not required.

关键词： FOR QUANTITATIVE EDS A NEW EXPRESSION OF X-RAY DEPTH DISTRIBUTION FUNCTION pz

An empirical orthogonal function model of total electron content over china

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An empirical orthogonal function model of total electron con...

LoI:Effcient relevance evaluation and filtering for distributed simulation

中国科学院地质与地球物理研究所2008学术年会

作者： Tian Mao,Weixing Wan,Xinan Yue,Lingfeng Sun,Biqiang Zhao, and Jianpeng Guo, 1 Institute of Geology and Geophysics,chinese academy of sciences,beijing,china. 2 National Center for Space Weather,china Meteorological Administration, beijing,china. 3 Wuhan Institute of Physics and Mathematics,chinese academy of sciences,Wuhan,china. 4 Graduate school of chinese academy of sciences,beijing,china.

[1]In this paper a climatology model of total electron content(TEC) over china has been developed on the basis of the empirical orthogonal function(EOF) analysis using Global Positioning System(GPS) data from the International Global Navigation Satellite System Service(IGS) and Crust Movement Observation Network of china(CMONOC) covering almost the whole chinese sector during *** model well represents observational data with mean bias of -0.00994 TECU(1 TECU = 1.0×10 el·m) and standard deviation of 5.42 *** the EOF model and IRI have been used in three-dimensional variational(3DVAR) data assimilation experiments separately,and results reveal that the ability of assimilation nowcasting for the EOF model is better as it provides a more authentic background.

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science in china(Series F) 2009年第3期52卷 470-489页

作者： ZHOU Zhong1,2 & WU Wei1,2 1 State Key Laboratory of Virtual Reality Technology and Systems, Beihang University, beijing 100191, china 2 school of Computer science and Engineering, Beihang University, beijing 100191, china

In large-scale distributed simulation, thousands of objects keep moving and interacting in a virtual environment, which produces a mass of messages. High level architecture （HLA） is the prevailing standard for modeling and simulation. It specifies two publish-subscribe mechanisms for message filtering： class-based and value-based. However, the two mechanisms can only judge whether a message is relevant to a subscriber or not. Lacking of the ability to evaluate the relevance, all relevant messages are delivered with the same priority even when congestion occurs. It significantly limits the scalability and performance of distributed simulation. Aiming to solve the relevance evaluation problem, speed up message filtering, and filter more unnecessary messages, a new relevance evaluation mechanism Layer of Interest （Lol） was proposed by this paper. Lol defines a relevance classifier based on the impact of spatial distance on receiving attributes and attribute values. An adaptive publish-subscribe scheme was built on the basis of Loh This scheme can abandon most irrelevant messages directly. Run-time infrastructure （RTI） can also apply congestion control by reducing the frequency of sending or receiving object messages based on each objects＇ Loh The experiment results verify the efficiency of message filtering and RTI congestion control.

关键词： distributed simulation high level architecture (HLA) relevance evaluation layer of interest (Lol) run-time infrastructure (RTI)

Cytotoxicity of nano-ZnO in cultured hippocampal neurons

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Cytotoxicity of nano-ZnO in cultured hippocampal neurons

Differential retardation of organic matter maturation by overpressure

The International Conference on NanoToxicology(ICNT2008):The 22nd Satellite Meeting of the 10th Annual Conference of china Association for science and Technology

作者： Lijuan Wang Lin Wang Fang Zhang WenJun Ding College of Life sciences Graduate University of chinese academy of sciences beijing 100049 china

＜正＞Background:Of the many types of nanoprocluets in current use,toxicity testing should obviously begin with those that pose the highest risk of environmental *** zinc oxide （ZnO）is a reasonable candidate for stu... 详细信息

关键词： cytotoxicity oxide nanoparticles neural cell zinc oxide

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science china Earth sciences 2004年第9期47卷 783-793页

作者： HAO Fang1,2, JIANG Jianqun1, ZOU Huayao1, FANG Yong1 & ZENG Zhiping2 1. Key Lab for Hydrocarbon Accumulation Mechanism in the Ministry of Education, Petroleum University, beijing 102249, china 2. Department of Petroleum Geology, china University of Geosciences, Wuhan 430074, china Key Lab for Hydrocarbon Accumulation Mechanism in the Ministry of Education Petroleum University Beijing 102249 China Department of Petroleum Geology China University of Geosciences Wuhan 430074 China

The thermal evolution of organic matter (OM) is composed of a series of reactions that are paralell and successive with each other. Different reactions have different activation energy, different rates of product concentration variation, and different volume expansion effects, and therefore have different responses to overpressure, which determines the differential retardation of different OM maturation reactions and maturity parameters. Based upon comprehensive studies on the OM maturation in different pressure systems in the Yinggehai, Qiongdongnan and Bohai Bay basins, 4 hierarchies of overpressure retardation have been recognized. (1) OM maturation in all aspects has been retarded by overpressure. (2) The thermal evolution of hydrocarbons and thermal degradation of hydrogen-rich kerogens has been retarded, but the thermal evolution of hydrogen-poor kerogen components has not been affected by overpressure. As a result, vitrinite reflectance has not been retarded. (3) The thermal cracking of hydrocarbons has been retarded, yet overpressure has had little or no effect on thermal degradation of kerogens. (4) Overpressure has no detectable effect on all aspects of OM maturation. The hierarchy that overpressure has retarded all aspects of OM maturation is the combined result of early overpressure (overpressure began to develop when the source rock was still immature) and the protracted maintenances of closed fluid system. Any case that overpressure had developed too late, or overpressure was too small to reach the threshold values, or overpressured fluid had been frequently released, could give rise to the occurrence of state 4 that overpressure had no detectable effect on all aspects of OM maturation. It seems that in many basins, overpressure retardation of hierarchies 2 and 3 developed where the most commonly used maturity parameter, vitrinite reflectance, had not been affected. In theses cases, multiple parameters must be used to distinguish overpressure retardati

关键词： overpressure, organic matter maturation, hydrocarbon generation, differential retardation.

Heat transfer characteristics of bio-materials irradiated by pulsed-laser

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Progress in Natural science:Materials International 2002年第12期12卷 52-56页

作者： HUAI Xiulan LIU Dengying, ZHOU Jianhua and YU Aibing(1. Institute of Engineering Thermophysics, chinese academy of sciences, beijing 100080, china 2. school of Materials science and Engineering, The University of New South Wales, Sydney, NSW 2052, Australia) chinese Acad Sci Inst Engn Thermophys Beijing 100080 Peoples R China Univ New S Wales Sch Mat Sci & Engn Sydney NSW 2052 Australia

The dynamic temperature variation of bio-materials induced by pulsed-laser irradiation is determined by a rapid transient temperature measuring system. The heat transfer characteristics of bio-materials, and the influence of pulse duration, power density, thickness and initial moisture content of bio-materials on heat transfer are studied. Based on the experiments, a mathematical model of bio-heat transfer is set up. Numerical simulation results show that the calculated results agree well with the experimental results, and bioheat transfer characteristics irradiated by pulsed-laser can be displayed well. Valuable information and experiences are provided for further experimental and theoretical investigation.

关键词： bio-materials dynamic temperature measurement pulsed-laser.

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计算机二维绘图系统的射影几何表征

计算机工程与应用 2002年第14期38卷 100-101,122页

作者：崔伟东田捷葛江伟中国科学技术大学研究生院(北京) 北京100039 中国科学院自动化研究所(北京) 北京100080

文章给出了一种在传统的计算机二维绘图系统增加射影几何方法的途径。该方法基于位于以视点为中心的单位球表面上的点与图像面上的点之间的投影变换。简要介绍了射影几何基础以及用它来处理视图的基本方法,用实例初步演示了该系统的某... 详细信息

文章给出了一种在传统的计算机二维绘图系统增加射影几何方法的途径。该方法基于位于以视点为中心的单位球表面上的点与图像面上的点之间的投影变换。简要介绍了射影几何基础以及用它来处理视图的基本方法,用实例初步演示了该系统的某些优点和准三维功能。

关键词：计算机二维绘图系统射影几何表征几何实体图形变换

Positional variation of antipodal cells in polyembryonic rice ApⅢ before and after fertilization

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Progress in Natural science:Materials International 2003年第11期 14-18页

作者： YUAN Liangchen 1,2, CHEN Yongzhe 2, MU Xijin 1 and LIN Jinxing 1*(1. Key Laboratory of Photosynthesis and Molecular Physiology, Institute of Botany, chinese academy of sciences, beijing 100093, china 2. Institute of Cell Biology and Genetics, school of Life science, Shandong University, Jinan 250100, china) Key Laboratory of Photosynthesis and Molecular Physiology，Institute of Botany，chinese academy of sciences，beijing 100093，china Institute of Cell Biology and Genetics，school of Life science，Shandong University，Jinan 250100，china Institute of Cell Biology and Genetics，school of Life science，Shandong University，Jinan 250100，china Key Laboratory of Photosynthesis and Molecular Physiology，Institute of Botany，chinese academy of sciences，beijing 100093，china

The variation in the position of antipodal cells before and after fertilization in polyembryonic rice strain ApⅢ was studied by using conventional sectioning technique. It was shown that initially the three antipodal cells lie at the chalazal end of the young embryo sacs. Along with the development of embryo sac, the antipodal cells proliferate into a multicellular structure containing up to about 20 cells. Most of the cells migrate to its dorsal side when the embryo sacs turn into mature. In a few embryo sacs the antipodal cells are situated in the positions adjacent to the egg apparatus at the micropylar end, while in other sacs, they spread from the midst of the embryo sac to the micropylar end clinging to the nucellar tissue. Furthermore, it is reported for the first time that cells of some egg apparatus or proembryos disorganize when antipodal cells lie at the micropylar end, indicating that the function of the antipodal cells may vary during the embryogenesis in rice ApⅢ.

关键词： polyembryonic rice antipodal cell embryo sac egg apparatus.