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Properties of mouse retinal ganglion cell dendritic growth during postnatal development

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Science china(Life sciences) 2010年第6期53卷 669-676页

作者： YANG XiuLan,SHI XiangMing & HE ShiGang State key laboratory of Brain and Cognitive sciences,institute of Biophysics,chinese academy of sciences,beijing 100101,china State key laboratory of Brain and Cognitive sciences Institute of Biophysics Chinese Academy of Sciences Beijing China

The property of dendritic growth dynamics during development is a subject of intense ***,we investigated the dendritic motility of retinal ganglion cells (RGCs) during different developmental stages,using ex vivo mouse retina explant culture,Semliki Forest Virus transfection and time-lapse *** results illustrated that during development,the dendritic motility underwent a change from rapid growth to a relatively stable state,i.e.,at P0 (day of birth),RGC dendrites were in a highly active state,whereas at postnatal 13 (P13) they were more stable,and at P3 and P8,the RGCs were in an intermediate *** any given developmental stage,RGCs of different types displayed the same dendritic growth rate and *** the mouse is the most popular mammalian model for genetic manipulation,this study provided a methodological foundation for further exploring the regulatory mechanisms of dendritic development.

关键词： retinal ganglion cells dendritic development time-lapse observation

PGE patterns of ores of Dajing Cu-polymetallic deposit in Linxi County, Inner Mongolia:Indicator to source of metallogenic elements

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chinese Science Bulletin 2002年第13期47卷 1119-1124页

作者： CHU Xuelei, SUN Min & ZHOU Meifuinstitute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china key laboratory of Mineral Resources, institute of Geology and Geophysics, chinese academy of sciences, beijing 100101, china Department institute of Geology and Geophysics Chinese Academy of Sciences Beijing China key laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Department of Earth sciences The University of Hong Kong Hong Kong China

By comparing PGE patterns of sulfide ores with that of basic-ultrabasic dikes occurring in the Dajing Cu-polymetallic deposit, we discover that there are similar positive slopes between the basic-ultrabasic dikes and the black ores composed mainly of sphalerite and galena, reflecting affinity of their source. The PGE patterns of the yellow ores composed basically of chalcopyrite, arsenopyrite and pyrite are actually different. One is close to the pattern of the mantle 1herzolite, and others resemble the pattern of the basic rocks. However, the concentrations of Ru are higher in the yellow ores, reflecting that sulfur attains or approaches saturation in their parent magma. The PGE characteristics of ores and dikes show that the magmas derived from the deep of crust and the metallogenic elements were supplied mainly by growth material of the crust. In addition, the mantle-derived magma also offered some elements.

关键词： Da Hinggan area polymetallic deposit PGE pattern hypomagma.

Molecular identification of species in Prunus sect. Persica (Rosaceae), with emphasis on evaluation of candidate barcodes for plants

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Journal of Systematics and Evolution 2011年第2期49卷 138-145页

作者： 1,2 Xu QUAN 1 Shi-Liang ZHOU 1 (State key laboratory of Systematic and Evolutionary Botany, institute of Botany, chinese academy of sciences, beijing 100093, china) 2 (Graduate School of the chinese academy of sciences, beijing 100049, china) (State key laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate School of the chinese academy of sciences Beijing 100049 China)

Species of Prunus L. sect. Persica are not only important fruit trees, but also popular ornamental and medicinal plants. Correct identification of seedlings, barks, or fruit kernels is sometimes required, but no reliable morphological characters are available. Nowadays, the technique of DNA barcoding has the potential to meet such requirements. In this study, we evaluated the suitability of 11 DNA loci (atpB-rbcL, trnH-psbA, trnL-F, trnS-G, atpF-H, rbcL, matK, rpoB, rpoC1, nad1, and internal transcribed spacer [ITS]) as candidate DNA barcodes for peaches, using samples from 38 populations, covering all the species in sect. Persica. On the whole, the primers worked well in this group and sequencing difficulties were met only in the case of ITS locus. Five loci (rbcL, matK, rpoB, rpoC, and nad1) have very low variation rates, whereas atpB-rbcL, atpF-H, trnH-psbA, trnL-F and trnS-G show more variability. The most variable loci, atpB-rbcL and trnH-psbA, can distinguish three of the five species. Two two-locus combinations, atpB-rbcL+trnL-F and atpB-rbcL+atpF-H, can resolve all five species. We also find that identification powers of the loci are method-dependent. The NeighborNet method shows higher species identification power than maximum parsimony, neighbor joining, and unweighted pair group method with arithmetic mean methods.

关键词： atpB-rbcL DNA barcode Prunus sect. Persica trnL-F.

Early scale effect and hemisphere superiority on the visual spatial attention:From the electrophysiological evidence of ERP

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Progress in Natural Science:Materials International 2004年第10期14卷 35-39页

作者： SONG Weiqun 1,3 ,GAO Yuan 1 and LUO Yuejia 1,2 (1.key laboratory of mental health,institute of psychology,chinese academy of sciences,beijing100101,china 2.School of Psy-chology,Southwest china Normal University,Chongqing400715,china 3.Graduate School of the chinese academy of sciences,Bei-jing100039,china) Lab. of mental health Inst. of Psychol. Chinese Acad. of Sci. Beijing 100101 China Graduate Sch. Chinese Acad. of Sci. Beijing 100039 China Sch. of Psychol. Southwest China Normal Univ. Chongqing 400715 China

The visual attention mechanism in the brain was studied among16young subjects through the precue-target visual search paradigm using the event-related potentials(ERPs)technique,with the attentive ranges cued with different scales of chinese *** results showed that the response time was shortened as the cue scale was reduced,while the amplitudes of the P1and N1components of the ERPs *** results not only provided the electrophysiological evidence supporting the spotlight theory,but also indicated that the spotlight effect occurred during the early period of the selected *** kinds of separation in the P2effect were *** separation was between the P1effect and P2effect,which meant that additional computation was needed when the spatial scale of attention was enlarged;the other was between the left and right hemisphere of the P2effect,which indicates that the at-tentive processing of the cue range mainly occurred in the left hemisphere.

关键词： visual spatial attention cue scale spotlight effect hemisphere superiority event-related potential(ERP)

Terrestrial transect study on driving mechanism of vegetation changes

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Science china Earth sciences 2008年第7期51卷 984-991页

作者： ZHANG YuJin1,2 & ZHOU GuangSheng1 1 State key laboratory of Vegetation and Environmental Change, institute of Botany, chinese academy of sciences, beijing 100093, china 2 Graduate University of chinese academy of sciences, beijing 100049, china State key laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

In terms of chinese climate-vegetation model based on the classification of plant functional types, to- gether with climatic data from 1951 to 1980 and two future climatic scenarios (SRES-A2 and SRES-B2) in china from the highest and the lowest emission scenarios of greenhouse gases, the distribution patterns of vegetation types and their changes along the Northeast china Transect (NECT) and the North-South Transect of Eastern china (NSTEC) were simulated in order to understand the driving mechanisms of vegetation changes under climatic change. The results indicated that the vegetation distribution patterns would change significantly under future climate, and the major factors driving the vegetation changes were water and heat. However, the responses of various vegetation types to the changes in water and heat factors were obviously different. The vegetation changes were more sensi- tive to heat factors than to water factors. Thus, in the future climate warming will significantly affect vegetation distribution patterns.

关键词： driving mechanism vegetation terrestrial transect climatic change plant functional types

Research progress on Drosophila visual cognition in china

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Science china(Life sciences) 2010年第3期53卷 374-384页

作者： GUO AiKe1,2,ZHANG Ke1,PENG YueQin1 & XI Wang1 1 institute of Neuroscience,State key laboratory of Neuroscience,Shanghai institutes for Biological sciences,chinese academy of sciences,Shanghai 200031,china 2 State key laboratory of Brain and Cognitive Science,institute of Biophysics,chinese academy of sciences,beijing 100101,china institute of Neuroscience State Key Laboratory of Neuroscience Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China State key laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing China

Visual cognition,as one of the fundamental aspects of cognitive neuroscience,is generally associated with high-order brain functions in animals and ***,as a model organism,shares certain features of visual cognition in common with mammals at the genetic,molecular,cellular,and even higher behavioral *** learning and memory to decision making,Drosophila covers a broad spectrum of higher cognitive behaviors beyond what we had *** with powerful tools of genetic manipulation in Drosophila,an increasing number of studies have been conducted in order to elucidate the neural circuit mechanisms underlying these cognitive behaviors from a genes-brain-behavior *** goal of this review is to integrate the most important studies on visual cognition in Drosophila carried out in china's Mainland during the last decade into a body of knowledge encompassing both the basic neural operations and circuitry of higher brain function in ***,we consider a series of the higher cognitive behaviors beyond learning and memory,such as visual pattern recognition,feature and context generalization,different feature memory traces,salience-based decision,attention-like behavior,and cross-modal leaning and *** discuss the possible general gain-gating mechanism implementing by dopamine-mushroom body circuit in fly's visual *** hope that our brief review on this aspect will inspire further study on visual cognition in flies,or even beyond.

关键词： Visual invariance recognition visual memory traces feature and context generalization selective attention cross-modality memory integration salience-based decision making

Numerical simulation of Richtmyer-Meshkov instability

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Science china Mathematics 2004年第Z1期47卷 234-244页

作者： FU Dexun, MA Yanwen, ZHANG Linbo & TIAN BaolinState key laboratory of Nonlinear Mechanics, institute of Mechanics, chinese academy of sciences, beijing 100080, china State key laboratory of Scientific and Engineering Computing, institute of Computational Mathematics, chinese academy of sciences, beijing 100080, china State key laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing China State key laboratory of Scientific and Engineering Computing Institute of Computational Mathematics Chinese Academy of Sciences Beijing China

The compressible Navier-Stokes equations discretized with a fourth order accurate compact finite difference scheme with group velocity control are used to simulate the Richtmyer-Meshkov (R-M) instability problem produced by cylindrical shock-cylindrical material interface with shock Mach number Ms=1.2 and density ratio 1:20 (interior density/outer density). Effect of shock refraction, reflection, interaction of the reflected shock with the material interface, and effect of initial perturbation modes on R-M instability are investigated numerically. It is noted that the shock refraction is a main physical mechanism of the initial phase changing of the material surface. The multiple interactions of the reflected shock from the origin with the interface and the R-M instability near the material interface are the reason for formation of the spike-bubble structures. Different viscosities lead to different spike-bubble structure characteristics. The vortex pairing phenomenon is found in the initial double mode simulation. The mode interaction is the main factor of small structures production near the interface.

关键词： R-M instability, direct numerical simulation, shock-interface interaction.

Paeonia rotundiloba(***)***:A new status in tree peonies(Paeoniaceae)

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Journal of Systematics and Evolution 2011年第5期49卷 464-467页

作者： De-Yuan HONG(State key laboratory of Systematic and Evolutionary Botany,institute of Botany,chinese academy of sciences,beijing 100093,china) (State key laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China)

Paeonia decomposita Hand.-*** *** is here raised to the specific rank,***(***) ***,based on its distinctiveness of four diagnostic characters:number of carpels;height of disk;number of leaflets of the lower leaves,and shape of the terminal leaflets;and unpublished molecular *** rotundiloba differs distinctly from *** in having carpels mostly 3,less often 2 or 4,very rarely 5(*** always 5,very occasionally 4 or 3),disk 8-15 mm high(vs.4-9.6 mm),leaflets mostly 19-39(vs.29-63) in number,and ratio of length to width of the terminal leaflets 1.09-1.93(vs.1.81-2.99).

关键词： china new status Paeonia decomposita Paeonia rotundiloba Sichuan statistical analysis.

CORRECTION METHODS FOR STEADY INCOMPRESSIBLE FLOWS

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Journal of Computational Mathematics 1999年第4期17卷 419-424页

作者： Jian Li(State key laboratory of Scientific and Engineering Computing, ICMSEC, chinese academy of sciences, beijing 100080, china) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京

Correction methods for the steady semi-periodic motion of incompressible fluid are investigated. The idea is similar to the influence matrix to solve the lack of vorticity boundary conditions. For any given boundary condition of the vorticity, the coupled vorticity-stream function formulation is solved. Then solve the governing equations with the correction boundary conditions to improve the solution. These equations are numerically solved by Fourier series truncation and finite difference method. The two numerical techniques are employed to treat the non-linear terms. The first method for small Reynolds number R equals 0-50 has the same results as that in M. Anwar and S.C.R. Dennis' report. The second one for R greater than 50 obtains the reliable results. (Author abstract) 4 Refs.

关键词： incompressible flow vorticity stream function numerical solution