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LEAFY HEAD2,which encodes a putative RNA-binding protein,regulates shoot development of rice

Cell Research 2006年第3期16卷 267-276页

作者： Guo Sheng Xiong~(1,3) Xing Ming Hu~2 Yong Qing Jiao~1 Yan Chun Yu~1 Cheng Cai Chu~1 Jia Yang Li~1 Qian Qian~2 Yong Hong Wang~11 State key laboratory of Plant Genomics and national Center for Plant Gene Research,Institute of Genetics and Developmental Biology,chinese academy of sciences,beijing 100101,china 2 State key laboratory of Rice Biology,china national Rice Research Institute,chinese academy of Agricultural sciences,Hangzhou 310006,china 3 Graduate University of chinese academy of sciences,beijing 100049,china State key laboratory of Plant Genomics and national Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China State key laboratory of Rice Biology China National Rice Research Institute Chinese Academy of Agricultural Sciences Hangzhou China

During vegetative development,higher plants continuously form new leaves in regular spatial and temporal *** with abnormal leaf developmental patterns not only provide a great insight into understanding the regulatorymechanism of plant architecture,but also enrich the ways to its modification by which crop yield could be ***,we reported the characterization of the rice leafy-head2 (lhd2) mutant that exhibits shortened plastochron,dwarfism,reduced tiller number,and failure of phase transition from vegetative to reproductive *** and histologicalstudy revealed that the rapid emergence of leaves in lhd2 was resulted from the rapid initiation ofleafprimordia whereasthe reduced tiller number was a consequence of the suppression of the tiller bud *** molecular and geneticanalysis showed that LHD2 encodes a putative RNA binding protein with 67% similarity to maize *** ofgenome-scale expression profiles between wild-type and lhd2 plants suggested that LHD2 may regulate rice shoot devel-opment through KNOXand hormone-related *** similar phenotypes caused by LHD2 mutation and the conservedexpression pattern of LHD2 indicated a conserved mechanism in controlling the temporal leaf initiation in grass.

关键词： phyllotaxy plastochron LHD2 RNA-binding protein stem elongation plant architecture Oryza sativa L

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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.

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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.

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Properties of Broad Band Continuum of Narrow Line Seyfert 1 Galaxies

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chinese Journal of astronomy and Astrophysics 2002年第6期2卷 501-524页

作者： Hong-Yan Zhou and Ting-Gui WangCenter for Astrophysics, University of Science and Technology of china, Hefei 230026national astronomical observatories, chinese Academic of Science, beijing 100012 Center for Astrophysics University of Science and Technology of China Hefei 230026 national astronomical observatories Chinese Academic of Science Beijing 100012

We have performed a statistical study of the properties of the broad band continuum of Narrow Line Seyfert 1 galaxies (NLS1s) by collecting ratio, infrared, optical and X-ray continuum data from various databases and compared the results with control samples of Broad Line Seyfert 1 galaxies (BLS1s). We find that the fraction (similar to 6%) of Radio Loud (RL) NLS1s is significantly less than that of BLS1s (similar to 13%), which is caused by the lack of radio-very-loud sources in the former. The rarity of RL NLS1s, especially radio-very-loud ones, is consistent with the scenario of small black hole and high accretion rate for NLS1s. Six new radio loud NLS1s are found and five RL NLS1 candidates are presented. In comparison with the BLS1s, the NLS1s tend to have stronger far infrared emission, cooler infrared colors and redder B - K color, which suggests that NLS1s are hosted by dust-richer nuclei. The NLS1s also show steeper soft X-ray spectrum and large soft X-ray to optical flux ratio, while a significant fraction show flat soft X-ray spectra. At least two factors can account for this, absorption and spectral variability. We also perform a correlation analysis between various broad band data. It is found that most correlations identified for NLS1s are also valid for radio quiet BLS1s: (1) the optical colors are anti-correlated with X-ray spectral index; (2) higher optical, Xray and NIR luminosity objects show bluer optical colors and red H - K color; (3) higher luminosity objects show warmer IRAS color; (4) the radio loudness correlates with B - K and X-ray to optical flux ratio. Radio loud objects behave somewhat differently in a few correlations.

关键词： galaxies : active galaxies : Seyfert radiation : continuum

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Interdecadal trend turning of global terrestrial temperature and precipitation during 1951-2002

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Progress in Natural Science:Materials International 2008年第11期18卷 1383-1393页

作者： Xiaohui Shi Xiangde Xu State key laboratory of Severe Weather,chinese academy of Meteorological sciences,beijing 100081,china State key laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China

A grid-by-grid counting of interdecadal trend turning(ITT)of annual mean surface air temperature(SAT)and total precipitation at 67,359 terrestrial grids in the period 1951-2002 is *** analysis of the last ITTs of SAT and total precipitation in the period,in the context of both occurrence time and linear trends after the breakpoint,indicates that a warming trend has become highly significant across most reagent of the world in the late 20th *** terrestrial grids have recorded an ITT of total precipitation in either the 1970s or 1980s,and 45.7% of the terrestrial grids in the study have seen a decreasing trend in total annual precipitation after the break- point,with the remaining 54.3% having experienced an increasing ***,global terrestrial regions have experienced either an increasingly warm and dry climate or an increasingly warm and wet *** analysis of ITT of regional mean SAT and total pre- cipitation in 22 regions shows that the Northern American continent has become increasingly warm and dry after the last interdecadal ***,the African continent has become increasingly warm and wet,with both Europe and most of Asia having the same *** South America and the West of Australia have experienced an opposite trend in climate,becoming increasingly cold and wet.

关键词： Global terrene Surface air temperature Precipitation Interdecadal trend turning

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Ambient noise near the sea-route

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Science china(Physics,Mechanics & astronomy) 2009年第1期52卷 40-45页

作者： HE Li1,2, LI ZhengLin1,3 & PENG ZhaoHui1 1 national laboratory of Acoustics, Institute of Acoustics, chinese academy of sciences, beijing 100190, china 2 Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china 3 NanHai laboratory of Acoustics, Institute of Acoustics, chinese academy of sciences, Haikou 570206, china national laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China NanHai laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Haikou China

Ambient noise data measured in an experiment conducted in shallow water near a sea-route were analyzed. It was observed that, at low frequency, the horizontal correlation has an obvious difference from that predicted by the classical ambient noise model. The theoretical analyses show that this phenomenon is caused by wind noise together with the discrete shipping noise nearby. An ambient noise model was proposed to include the effects caused by both the noise sources. Data measured at different times verify that the proposed model can be used to forecast the ambient noise field in shallow water near the sea-route.

关键词： ambient noise model horizontal correlation discrete ships

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Near-Infrared Solar Electric Field Telescope

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天文研究与技术 1999年第S1期 120-123页

作者： Song Guofeng 1 (beijing astronomical Observatory, The chinese academy of sciences, beijing 100012, china) 2 (national astronomical observatories, The chinese academy of sciences, beijing 100012, china)

The infrared monochromatic image of corona was reported in 1975. The Solar Infrared electric field observing and researching was proposed in 1986 and infrared solar magnetic field observing was suggested in 1987. These observing data describes various states of solar atmosphere. To varying degrees, compared with traditional system, near infrared system has its special characteristics. In this paper, we present a vacuum solar telescope with a near infrared (at 8438 angstrom～10830 angstrom) filter system which is designed to measure the solar electric field in Huairou workstation of beijing astronomical Observatory (BAO). The vacuum optical telescope will consist of a primary mirror in 35cm Diameter, a Gregorian mirror, two vacuum windows, a collimating lens and an imagine lens. The filter with polarizing analyzer will consist of two prefilters, one liquid crystal analyzers, a universal birefringent filter which spectral range is in 8000 angstrom～11000 angstrom and pass band 0 25 angstrom at 10830 angstrom. The birefringent filter and the optical system of the telescope are described in details. We expect to achieve an electric field observing system, two dimensional monochromatic image observational system of corona. It also can be turned across the spectral line to obtain line profiles of two dimensional of the field.

关键词： Infrared Solar

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Research of the Gas-solid Flow Character Based on the DEM Method

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Journal of Thermal Science 2011年第6期20卷 521-526页

作者： Xueyao Wang and Yunhan Xiao Research Center for Clean Energy and Power,chinese academy of sciences key laboratory of Advanced Energy and Power,chinese academy of sciences (Institute of Engineering Thermophysics),beijing,100190,china Research Center for Clean Energy and Power Chinese Academy of Sciences Beijing China key laboratory of Advanced Energy and Power Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing China

Numerical simulation of gas-solid flow behaviors in a rectangular fluidized bed is carried out three dimensionally by the discrete element method (DEM).Euler method and Lagrange method are employed to deal with the gas phase and solid phase *** collided force among particles,striking force between particle and wall,drag force,gravity,Magnus lift force and Saffman lift force are considered when establishing the mathematic ***-sphere model is used to describe the collision of *** addition,the Euler method is also used for modeling the solid phase to compare with the results of *** flow patterns,particle mean velocities,particles' diffusion and pressure drop of the bed under typical operating conditions are *** results show that the DEM method can describe the detailed information among particles,while the Euler-Euler method cannot capture the micro-scale *** matter which method is used,the diffusion of particles increases with the increase of gas *** the gathering and crushing of particles cannot be simulated,so the energy loss of particles' collision cannot be calculated and the diffusion by using the Euler-Euler method is *** addition,it is shown by DEM method,with strengthening of the carrying capacity,more and more particles can be schlepped upward and the dense suspension upflow pattern can be ***,the results given by the Euler-Euler method are not consistent with the real situation.

关键词： DEM gas-solid flow numerical simulation

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Spectroscopic and photometric observations of unidentified ultraviolet variable objects in the GUVV-2 Catalog

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Research in astronomy and Astrophysics 2011年第7期11卷 833-842页

作者： You Li Jing Wang Jian-Yan Wei Xiang-Tao He Department of astronomy Beijing Normal University Beijing 100875 China national astronomical observatories Chinese Academy of Sciences Beijing 100012 China

An NUV-optical diagram composed from sources from the second Galaxy Evolution Explorer（GALEX） Ultraviolet Variability（GUVV-2） Catalog provides us with a method to tentatively classify the unknown GUVV-2 sources by their NUV-optical *** the purpose of testing the correctness and generality of the method,we carry out a program on the spectroscopic observations of the unidentified GUVV-2 *** spectroscopic identification of these 37 sources are 19 type-A to-F stars,10 type-G to-K stars and 7 M dwarf stars together with an *** also present the light curves in the R-band for two RR Lyrae star candidates selected from the NUV-optical diagram,both of which undergo cyclic *** their light curves and colors,we classify them as RR Lyrae *** confirm the re-sults,we show a color-color diagram for the 37 newly identified spectroscopic objects compared with previously identified ones,which are consistent with our previous re-sults,indicating that the ultraviolet variable sources can initially be classified by their NUV/optical color-color diagram.

关键词： stars:variables:general—galaxies:active—methods:observational—ultraviolet emission

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Relative importance of water, energy, and heterogeneity in determining regional pteridophyte and seed plant richness in china

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Journal of Systematics and Evolution 2011年第2期49卷 95-107页

作者： 1,2,3 Sheng-Bin CHEN § 1 Gao-Ming JIANG 3 Zhi-Yun OUYANG 3 Wei-Hua XU 3 Yi XIAO 1 (State key laboratory of Vegetation and Environmental Change, Institute of Botany, chinese academy of sciences, beijing 100093, china) 2 (Graduate University of the chinese academy of sciences, beijing 100049, china) 3 (State key laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085, china) (State key laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of the chinese academy of sciences Beijing 100049 China) (State key laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China)

Environmental variables, such as ambient energy, water availability, and environmental heterogeneity have been frequently proposed to account for species diversity gradients. How taxon-specific functional traits define large-scale richness gradients is a fundamental issue in understanding spatial patterns of species diversity, but has not been well documented. Using a large dataset on the regional flora from china, we examine the contrast spatial patterns and environmental determinants between pteridophytes and seed plants which differ in dispersal capacity and environmental requirements. Pteridophyte richness shows more pronounced spatial variation and stronger environmental associations than seed plant richness. Water availability generally accounts for more spatial variance in species richness of pteridophytes and seed plants than energy and heterogeneity do, especially for pteridophytes which have high dependence on moist and shady environments. Thus, pteridophyte richness is disproportionally affected by water-related variables; this in turn results in a higher proportion of pteridophytes in regional vascular plant floras (pteridophyte proportion) in wet regions. Most of the variance in seed plant richness, pteridophyte richness, and pteridophyte proportion explained by energy is included in variation that water and heterogeneity account for, indicating the redundancy of energy in the study extent. However, heterogeneity is more important for determining seed plant distributions. Pteridophyte and seed plant richness is strongly correlated, even after the environmental effects have been removed, implying functional linkages between them. Our study highlights the importance of incorporating biological traits of different taxonomic groups into the studies of macroecology and global change biology.

关键词： habitat heterogeneity pteridophytes seed plants species richness water-energy hypothesis.

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