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Phylogeny and species delimitation of the C-genome diploid species in Oryza

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Journal of Systematics and Evolution 2011年第5期49卷 386-395页

作者： 1,2.Li-Li ZANG 1~Xin-Hui ZOU 1~Fu-Min ZHANG 3,4~Ziheng YANG 1,2.Song GE 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of {2.,beijing 100093,china) 2.Graduate University of the chinese academy of sciences,beijing 100049,china) 3(Department of Biology,University College London,London WC1E 6BT,United Kingdom) 4(center for Computational and Evolutionary Biology,Institute of Zoology,chinese academy of {2.,beijing 100101,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of the chinese academy of sciences Beijing 100049 China) (Department of Biology University College London London WC1E 6BT United Kingdom) (center for Computational and Evolutionary Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China)

The diploid Oryza species with C-genome type possesses abundant genes useful for rice improvement and provides parental donors of many tetraploid species with the C-genome(BBCC,CCDD).Despite extensive studies,the phylogenetic relationship among the C-genome species and the taxonomic status of some taxa remain *** this study,we reconstructed the phylogeny of three diploid species with C-genome(Oryza officinalis,***,and ***) based on sequences of 68 nuclear single-copy *** obtained a fully resolved phylogenetic tree,clearly indicating the sister relationship of *** and ***,with *** being the more divergent *** phylogenies of the C-genome species found in previous studies might result from lineage sorting,introgression/hybridization and limited number of genetic markers *** further applied a recently developed Bayesian species delimitation method to investigate the species status of the Sri Lankan and African *** of two datasets(68 genes with a single sample,and 10 genes with multiple samples) support the distinct species status of the Sri Lankan and African *** addition,we evaluated the impact of the number of sampled individuals and loci on species *** simulation suggests that sampling multiple individuals is critically important for species delimitation,particularly for closely related species.

关键词： Bayesian species delimitation Oryza phylogeny taxonomy.

Identifying heavy hitters in high-speed network monitoring

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Science china(Information sciences) 2010年第3期53卷 659-676页

作者： ZHANG Yu1, FANG BinXing1,2.& ZHANG YongZheng2.1research center of Computer Network and Information Security Technology, Harbin Institute of Technology, Harbin 150001,{2. 2.0} center of Information Security, Institute of Computing Technology, chinese academy of sciences, beijing 100190,{2. research center of Computer Network and Information Security Technology Harbin Institute of Technology Harbin China research center of Information Security Institute of Computing Technology Chinese Academy of Sciences Beijing China

Identifying heavy hitters in a network traffic stream is important for a variety of network applications ranging from traffic engineering to anomaly detection such as detection of denial-of-service attacks. Existing methods generally examine newly arriving items in the stream, perform a small number of operations using a small amount of memory, and still provide guarantees on the identifying accuracy. In high-speed network monitoring, the update speed per item is extremely critical. However, so far as we know, there are no identifying algorithms which can provide constant update time (O(1)) in a weighted data stream. In this paper, we present an algorithm named Weighted Lossy Counting (WLC) which is able to identify heavy hitters in a high-speed weighted data stream with constant update time. WLC employs a novel efficient partially ordered data structure which is able to provide a fast per-item update speed while keeping the memory cost relatively low. We compare WLC with state-of-the-art algorithms for finding heavy hitters in real traffic traces. The experimental results show that WLC performs well in accuracy (recall, precision and average relative error) as other algorithms; moreover it has a much higher update speed at the cost of relatively larger memory space used. A theoretical worst-case memory bound of WLC is also derived in this paper; however, experiments with long real traffic traces show that WLC requires much less space than the theoretical bound in practice.

关键词： network traffic monitoring heavy hitter weighted data streams

Extremal eigenvalues of measure differential equations with fixed variation

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Science china Mathematics 2010年第10期53卷 2573-2588页

作者： ZHANG MeiRong 1,2.1 Department of Mathematical sciences,Tsinghua University,beijing 100084,{2. 2.Zhou Pei-Yuan center for applied Mathematics,Tsinghua University,beijing 100084,{2. Department of Mathematical sciences Tsinghua University Beijing China Zhou Pei-Yuan center for applied Mathematics Tsinghua University Beijing China

In this paper we will study eigenvalues of measure differential equations which are motivated by physical problems when physical quantities are not absolutely *** taking Neumann eigenvalues of measure differential equations as an example,we will show how the extremal problems can be completely solved by exploiting the continuity results of eigenvalues in weak* topology of measures and the Lagrange multiplier rule for nonsmooth *** results can give another explanation for extremal eigenvalues of SturmLiouville operators with integrable potentials.

关键词： measure differential equation eigenvalue extremal value weak* topology Frechét derivative sub-differential

Environmental analysis of mercury in china

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Journal of Environmental sciences 2000年第S1期12卷 9-11页

作者： CHEN Jian\|hua 1, CHEN Le\|tian 1, LIN Yu\|huan 1, QI Xiao\|fan 1, SHI Wei 2.(1. research center for Eco\|Environmental {2., chinese academy of sciences, beijing 100085, china 2. Institute of applied Chemistry, chinese academy of sciences, C

This paper summarizes some of the research and evaluation about mercury analysis in environment during the past years in china. The main contents are as follows: determination of total mercury and speciation of mercury compounds in atmosphere;storage and treatment of mercury in water samples; pre\|treatment of solid samples; determination of total mercury and analysis of mercury species; certified reference materials.

关键词： analysis mercury china

Systematic study of survival probability of excited superheavy nuclei

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 109-113页

作者： XIA ChengJun1, SUN BaoXi1, ZHAO EnGuang2.3 & ZHOU ShanGui2.3 1College of applied sciences, {2. University of Technology, {2. 10012., china 2.nstitute of Theoretical Physics, chinese academy of sciences, {2. 100190, china 3center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000, china College of applied sciences Beijing University of Technology Beijing China Institute of Theoretical Physics Chinese Academy of Sciences Beijing China center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou China

The stability of excited superheavy nuclei (SHN) with 100 Z 134 against neutron emission and fission is investigated by using a statistical model. In particular, a systematic study of the survival probability against fission in the 1n-channel of these SHN is made. The present calculations consistently take the neutron separation energies and shell correction energies from the calculated results of the finite range droplet model which predicts an island of stability of SHN around Z = 115 and N = 179. It turns out that this island of stability persists for excited SHN in the sense that the calculated survival probabilities in the 1n-channel of excited SHN at the optimal excitation energy are maximized around Z = 115 and N = 179. This indicates that the survival probability in the 1n-channel is mainly determined by the nuclear shell effects.

关键词： survival probability superheavy elements island of stability neutron emission fission

Latest progress on interactions between VLF/ELF waves and energetic electrons in the inner magnetosphere

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Science china Earth sciences 2010年第3期53卷 317-326页

作者： XIAO FuLiang1,2. ZONG QiuGang3, SU ZhenPeng4, TIAN Tian3 & ZHENG HuiNan4 1 School of Physics and Electronic sciences, Changsha University of Science and Technology, Changsha 410004, china 2.State Key Laboratory of {2. Weather, chinese academy of sciences, beijing 100190, china 3 Institute of {2. Physics and applied Technology, Peking University, beijing 100871, china 4 CAS Key Lab for Basic Plasma Science, School of Earth and {2. sciences, University of Science and Technology of china, Hefei 2.002., china School of Physics and Electronic sciences Changsha University of Science and Technology Changsha China State Key Laboratory of space Weather Chinese Academy of Sciences Beijing China Institute of space Physics and applied Technology Peking University Beijing China CAS Key Lab for Basic Plasma Science School of Earth and Space Sciences University of Science and Technology of China Hefei China

Interactions between very/extremely low frequency (VLF/ELF) waves and energetic electrons play a fundamental role in dynamics occurring in the inner magnetosphere. Here, we briefly discuss global properties of VLF/ELF waves, along with the variability of the electron radiation belts associated with wave-particle interactions and radial diffusion. We provide cases of electron loss and acceleration as a result of wave-particle interactions primarily due to such waves, and particularly some preliminary results of 3D evolution of phase space density from our currently developing 3D code. We comment on the existing mechanisms responsible for acceleration and loss, and identify several critical issues that need to be addressed. We review latest progress and suggest open questions for future investigation.

关键词： wave-particle interaction VLF/ELF waves energetic electrons acceleration and loss inner magnetosphere

Representations of Real and Complex Stability Radii of 2.Dimensional LinearSystems

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 299-301页

作者： Lequan Min1.2.Ning Song1(l applied Science School, University of Science and Technology’ beijing, beijing 100083, china2.3} center of Advanced Science and Technology, beijing 100080, china) applied Science School University of Science and Technology Beijing Beijing 100083 China china center of Advanced Science and Technology Beijing 100080 China

Rigorous proofs are given for the representations of real and complex stability' radii of 2.dimensional linear systems. This representations can be used to analyze the robustness of a nominal 2.dimensional linear system under pelturbation of the system parameters, in particular testing the effect of numerical algorithms which are used to calculate the real stability radii of higher dimensional piecewise-linear systems.

关键词： linear systems robustness stability radii

PLS path model building:A multivariate approach to land price studies-A case study in beijing

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Progress in Natural Science:Materials International 2009年第11期19卷 1643-1649页

作者： Wenjie Wu~(a,b),Wenzhong Zhang~(a,*) a Institute of Geographic sciences and Natural Resources research,CAS,{2. 100101,china b Graduate University of chinese academy of sciences,{2. 100049,china Institute of Geographic sciences and Natural Resources research CAS Beijing 100101 China Graduate University of chinese academy of sciences Beijing 100049 China

Previous studies have revealed that statistical methods can be used to analyze land-leasing parcel ***,the conventional statistical methods used in land analysis have some limitations,especially in cases of limited observational *** this paper,with the help of geographic information system(GIS) techniques,a partial least squares(PLS) path model is applied to study the relationship between residential land prices and various determinants through a case study of beijing in *** a preliminary analysis,four latent variables are selected:accessibility of the workplace {2.,livability,traffic,and environment *** results show that the observation variables have a strong explanatory power for their corresponding latent variables,and the four latent variables have varying impacts on residential land *** the latent variables,accessibility to the workplace {2. has the strongest impact on the residential land price.

关键词： Land PLS path model GIS beijing

Primary scientific results of Chang'E-1 lunar mission

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Science china Earth sciences 2010年第11期53卷 1565-1581页

作者： OUYANG ZiYuan1,2. LI ChunLai1, ZOU YongLiao1, ZHANG HongBo1, Lü Chang1, LIU JianZhong1, LIU JianJun1, ZUO Wei1, SU Yan1, WEN WeiBin1, BIAN Wei1, ZHAO BaoChang3, WANG JianYu4, YANG JianFeng3, CHANG Jin5, WANG HuanYu6, ZHANG XiaoHui7, WANG ShiJin7, WANG Min1, REN Xin1, MU LingLi1, KONG DeQing1, WANG XiaoQian1, WANG Fang1, GENG Liang1, ZHANG ZhouBin1, ZHENG Lei1, ZHU XinYing1, ZHENG YongChun1, LI JunDuo1, ZOU XiaoDuan1, XU Chun1, SHI ShuoBiao1, GAO YiFei1 & GAO GuanNan1 1 National Astronomical Observatories, chinese academy of sciences, beijing 100012.{2. 2.Institute of Geochemistry, chinese academy of sciences, Guiyang 550002.{2. 3 Xi’an Institute of Optics and Precision Mechanics, chinese academy of sciences, Xi’an 710119,{2. 4 Shanghai Institute of Technical Physics, chinese academy of sciences, Shanghai 2.0083,{2. 5 Purple Mountain Observatory, chinese academy of sciences, Nanjing 2.0008,{2. 6 Institute of High Energy Physics, chinese academy of sciences, beijing 100049,{2. 7 center for space Science and applied research, chinese academy of sciences, beijing 100190,{2. National Astronomical Observatories Chinese Academy of Sciences Beijing China Institute of Geochemistry Chinese Academy of Sciences Guiyang China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an China Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai China Purple Mountain Observatory Chinese Academy of Sciences Nanjing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China center for space Science and {2. research Chinese Academy of Sciences Beijing China

The strategic plan for the development of the unmanned chinese Lunar Exploration Program is characterized by three distinct stages: "orbiting around", "landing on" and "returning from" the Moon. The first chinese lunar probe, Chang'E-1, which was successfully launched on October 2.th, 2.07 at Xichang Satellite Launch {2., and guided to crash on the Moon on March 1st, 2.09, at 52.36°E, 1.50°S, in the north of Mare Fecunditatis, is the first step towards the "orbiting around" stage. The Chang'E-1 mission lasted 495 days, exceeding the expected life-span by about four months. A total of 1.37 TB raw data was received from Chang'E-1. It was then processed into 4 TB scientific data products at various levels. Many scientific results have been obtained by analyzing these data, including especially the "global lunar image from the first chinese lunar explora- tion mission". All scientific goals of Chang'E-1 have been achieved. It provides much useful materials for further advances of lunar sciences and planetary chemistry. Meanwhile, these results will serve as a firm basis for future chinese lunar missions.

关键词： lunar orbiter Chang’E-1 scientific data results