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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 sciences,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 sciences,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.

Characterization of GLUT4-containing vesicles in 3T3-L1 adipocytes by total internal reflection fluorescence microscopy

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Science china(Life sciences) 2009年第7期52卷 665-671页

作者： WANG Yan1,2,ZHANG JinZhong1,2,CHEN Yu1,2,JIANG Li1,2,JI Wei1,2 & XU Tao1 1 National Laboratory of Biomacromolecules,Institute of Biophysics,chinese academy of sciences,beijing 100101,china 2 graduate university of chinese academy of sciences,beijing 100049,china National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China

Insulin-responsive GLUT4(glucose transporter 4) translocation plays a major role in regulating glucose uptake in adipose tissue and *** or not there is a specialized secretory GSV(GLUT4 storage vesicle) pool,and more importantly how GSVs are translocated to the PM(plasma membrane) under insulin stimulation is still under *** the present study,we systematically analyzed the dynamics of a large number of single GLUT4-containing vesicles in 3T3-L1 adipocytes by TIRFM(total internal reflection fluorescence microscopy).We found that GLUT4-containing vesicles can be classified into three groups according to their mobility,namely vertical,stable,and lateral GLUT4-containing *** these groups,vertical GLUT4-containing vesicles exclude transferrin receptors and move towards the PM specifically in response to insulin stimulation,while stable and lateral GLUT4-containing vesicles contain transferrin receptors and show no insulin *** data demonstrate that vertical GLUT4-containing vesicles correspond to specialized secretory GSVs,which approach the PM directly and bypass the constitutive recycling pathway.

关键词： GLUT4 IRAP-pHluorin GSV transferring TIRFM

A fast onboard star-extraction algorithm optimized for the SVOM Visible Telescope

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Science china(Physics,Mechanics & Astronomy) 2010年第S1期53卷 51-55页

作者： WANG TianZhou1,2,QIU YuLei1,CAI HongBo1 & DENG JingSong1 1 National Astronomical Observatories,chinese academy of sciences,beijing 100012,china 2 graduate university of chinese academy of sciences,beijing 100049,china National Astronomical Observatories Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China

The Space multi-band Variable Object Monitor(SVOM) is a proposed chinese astronomical satellite,dedicated to the detection,localization and measurement of gamma-ray bursts(GRBs) on a cosmological *** efficient algorithm is developed for the purpose of onboard star extraction from the CCD images obtained with the Visible Telescope(VT) onboard the *** CCD pixel coordinates of the reference stars will be used to refine the astronomical position of the satellite,which will facilitate triggering rapid ground-based follow-up observations of the *** this algorithm,the image is divided into a number of grid cells and the "global" pixel-value maximum within each cell is taken as the first-guess position of a "bright" *** correct center position of a star is then computed using a simple iterative *** two additional strategies,i.e.,scanning the image only by even(or odd) lines or in a black-white chess board mode,we propose to further reduce the time to extract the *** examine the efficiency of the above algorithms,we applied them to the experimental images obtained with a ground-based *** find that the accuracy of the astronomical positioning achieved by our method is comparable to that derived by using the conventional star-extraction method,while the former needs about 25 times less CPU time than the *** will significantly improve the performance of the SVOM VT mission.

关键词： gamma-ray burst(GRBs) SVOM VT on board computation

Three-dimensional decomposition method of global atmospheric circulation

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Science china Earth sciences 2008年第3期51卷 386-402页

作者： LIU HaiTao1,2,3, HU ShuJuan4, XU Ming5 & CHOU JiFan6,7 1 State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china 2 graduate university of chinese academy of sciences, beijing 100049, china 3 beijing Climate Center, beijing 100089, china 4 Department of Mathematics, Lanzhou university, Lanzhou 730000, china 5 Shanghai Typhoon Institute, Shanghai 200030, china 6 Department of Atmospheric sciences, Lanzhou university, Lanzhou 730000, china 7 china Meteorological Administration Training Center, beijing 100089, china State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China beijing Climate Center Beijing China Department of Mathematics Lanzhou University Lanzhou China Shanghai Typhoon Institute Shanghai China Department of Atmospheric sciences Lanzhou University Lanzhou China china Meteorological Administration Training Center Beijing China

By adopting the idea of three-dimensional Walker, Hadley and Rossby stream functions, the global atmospheric circulation can be considered as the sum of three stream functions from a global per- spective. Therefore, a mathematical model of three-dimensional decomposition of global atmospheric circulation is proposed and the existence and uniqueness of the model are proved. Besides, the model includes a numerical method leading to no truncation error in the discrete three-dimensional grid points. Results also show that the three-dimensional stream functions exist and are unique for a given velocity field. The mathematical model shows the generalized form of three-dimensional stream func- tions equal to the velocity field in representing the features of atmospheric motion. Besides, the vertical velocity calculated through the model can represent the main characteristics of the vertical motion. In sum, the three-dimensional decomposition of atmospheric circulation is convenient for the further in- vestigation of the features of global atmospheric motions.

关键词： three-dimensional decomposition of the global atmospheric circulation generalized Walker Hadley and Rossby stream functions existence and uniqueness vertical motion

Synthesis and characterization of LiCo_(1/3)Ni_(1/3)Mn_(1/3)O_2 prepared by Pechini process

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Rare Metals 2006年第Z1期25卷 7-11页

作者： LI Zhigang WANG Tiandiao KANG Xueya Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of Sciences Urumuqi 830011 China graduate university of chinese academy of sciences Beijing 100049 China Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of Sciences Urumuqi 830011 China Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of Sciences Urumuqi 830011 China

Layered cathode material LiCo1/3Ni1/3Mn1/3O2 was synthesized by Pechini process, and investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM) and galvanostatic charge/discharge cycling. The sample is well-crystallized and has a phase-pure a-NaFeO2 structure. The particle sizes are uniform, and distributed in the range of 20-200 nm. The initial discharge capacity of the Li/LiCo1/3Ni1/3Mn1/3O2 cell was about 149 mAh·g-1 when it was cycled at a voltage range of 4.5-2.3 V with a specific current of 0.25 mA. The result is better in comparison with solid-state solution method. The synthetic procedure was discussed. Three major reactions: chelation, esterification, and polymerization successively occurred.

关键词： layered cathode material LiCo_(1/3)Ni_(1/3)Mn_(1/3)O_2 Pechini method structure morphology electrochemical properties

Electronic structure and magnetism of Fe-doped SiC nanotubes

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1582-1589页

作者： ZHANG WeiHu1,2,3,ZHANG FuChun3,ZHANG ZhiYong4,LU ShuYuan5 & YANG YanNing3 1 Xi’an Institute of Optics and Precision Mechanics,chinese academy of sciences,Xi’an 710068,china 2 graduate university of chinese academy of sciences,beijing 100049,china 3 College of Physics and Electronic Information,Yan’an university,Yan’an 716000,china 4 Information Science and Technology Institution,Northwest university,Xi’an 710127,china 5 Department of Telecommunications,Xi’an Institute of Posts and Telecommunications,Xi’an 710121,china Xi’an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an China graduate university of chinese academy of sciences Beijing China College of Physics and Electronic Information Yan’an University Yan’an China Information Science and Technology Institution Northwest University Xi’an China Department of Telecommunications Xi’an Institute of Posts and Telecommunications Xi’an China

The electronic structure and magnetic properties of Fe-doped SiC nanotubes are investigated by using the first-principles method based on density functional theory(DFT) in the local spin density approximation(LSDA).The calculation results indicate that the SiC nanotube of Fe substitution for C exhibits antiferromagnetism while ferromagnetism features prominently when Fe substitutes *** is a kind of half-metal magnetic *** formation energy calculation results show that the formation energy of ferromagnetic structure is 3.2 eV lower than that of antiferromagnetic *** atoms are more likely to replace Si ***-orbit coupling induces electron spin polarization in the ground ***,the doping Fe atoms make relaxation towards the outside of the tube to some extent and larger geometric distortion occurs when Fe substitutes C,but the whole geometric structure of SiC nanotubes is not damaged due to the *** is revealed in the calculation of energy band structure and density of states that more dispersed distribution of energy levels is produced near the Fermi *** Fe substitution for Si,obviously there are spin-split and intense p-d hybrid effects by Si 3p electron spins and Fe 3d electron spins localized at the exchanging interactions between magnetic transitional metal(TM) *** electronic density results indicate that system magnetic moments are mainly generated by the unpaired 3d electrons of Fe *** these results show that the transition metal doping SiC nanotube could be a potential route to fabricating the promising magnetic materials.

关键词： SiC nanotube the first-principles doped magnetic properties

The flhDC gene affects motility and biofilm formation in Yersinia pseudotuberculosis

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Science china(Life sciences) 2007年第6期50卷 814-821页

作者： WANG Yao1, DING LiSha1,2, HU YangBo1,2, ZHANG Yong1,2, YANG BaoYu1 & CHEN ShiYun1 1 Wuhan Institute of Virology, chinese academy of sciences, Wuhan 430071, china 2 graduate university of chinese academy of sciences, beijing 100049, china Wuhan Institute of Virology Chinese Academy of Sciences Wuhan China graduate university of chinese academy of sciences Beijing China

The flagella master regulatory gene flhDC of Yersinia pseudotuberculosis serotype III (YPIII) was mu- tated by deleting the middle region and replaced by a tetracycline resistant gene, and the subsequent mutant strain named YPIII?flhDC was obtained. Swimming assay showed that the swimming motility of the mutant strain was completely abolished. The promoter region of the flagella second-class regula- tory gene fliA was fused with the lux box, and was conjugated with the mutant and the parent strains respectively for the first cross. LUCY assay result demonstrated that flhDC regulated the expression of fliA in YPIII as reported in E. coli. Biofilm formation of the mutant strain on abiotic and biotic surfaces was observed and quantified. The results showed that mutation of flhDC decreased biofilm formation on both abiotic and biotic surfaces, and abated the infection on Caenorhabdtis elegans. Our results suggest that mutation of the flagella master regulatory gene flhDC not only abolished the swimming motility, but also affected biofilm formation of YPIII on different surfaces. The new function of flhDC identified in this study provides a novel viewpoint for the control of bacterial biofilm formation.

关键词： Yersinia pseudotuberculosis, flhDC, motility, biofilm

A cyclic behavior of CME accelerations for accelerating and decelerating events

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Research in Astronomy and Astrophysics 2009年第10期9卷 1165-1172页

作者： Peng-Xin Gao Ke-Jun Li National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China graduate university of chinese academy of sciences Beijing 100049 China

We investigate the cyclic evolutionary behavior of CME accelerations for accelerating and decelerating CME events in cycle 23 from 1997 January to 2007 December. It is found that the absolute values of semiannual mean accelerations of both accelerating and decelerating CME events roughly wax and wane in a cycle, delaying the sunspot cycle in time phase. We also investigate the semiannual number of CMEs with positive and neg- ative acceleration and find that there are more decelerating CME events than accelerating CME events during the maximum period of a cycle （about three years）, but there are more accelerating CME events than decelerating CME events during the rest of the time interval of the cycle. Our results seem to suggest that the different driving mechanisms may be acting accelerate and decelerate CME events; for accelerating CME events, the propelling force （Fp） statistically seems to play a significant role in pushing CMEs outward; for decelerating CME events, the drag （Fd） statistically seems to play a more effective role in determining CME kinematic evolution in the outer corona. During the maximum period of a cycle, because of the V^2 dependence, Fd is generally stronger; because of the magnetic field dependence, Fp is also generally stronger. Thus, the absolute values of both the negative and positive accelerations are generally larger during that time. Because of the V^2 dependence, Fd may be more effective during the maximum period of a cycle. Hence, there are more decelerating CME events than accelerating CME events during that time. During the minimum time interval of a cycle, CMEs have relatively small speeds, and Fp may be more effective. Therefore, there are more accelerating CME events than decelerating CME events during that time.

关键词： Sun corona -- Sun coronal mass ejections (CMEs)

Monitoring Dynamic Change of Land Cover Based on SVM and Satellite Images in Hanoi,Vietnam

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Wuhan university Journal of Natural sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2, LIU Chuang1, 3 1. Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china 2. graduate university of chinese academy of sciences, beijing 100049, china 3. College of Resources Science and Technology, beijing Normal university, beijing 100875, china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate university of chinese academy of sciences Beijing China College of Resources Science and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (SVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993,the enhanced the-matic mapper plus (ETM+) image in 2000,and the image with the charge-coupled device camera (CCD) on the china-Brazil earth resources satellite (CBERS) in 2008 were used. Six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993 to 2008. There were 12 637.54 hm2 cropland de-creased between 1993 and 2000,and 8 227.6 hm2 cropland de-creased between 2000 and 2008. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERS dataset has the application potential in world resources researches.

关键词： land cover the china-Brazil earth resources satellite (CBERS) support vector machine (SVM) change detection