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Pollen limitation and variation in floral longevity in gynodioecious Potentilla tanacetifolia

Journal of Systematics and Evolution 2011年第6期49卷 539-545页

作者： 1,2.ong YAO 1Yi-Bo LUO 1(state key {2. 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) (state key {2. of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of the chinese academy of {2. Beijing 100049 China)

Pollination limitation is common in flowering plants and is thought to be a factor driving the evolution of floral *** plasticity of floral longevity to pollination may be an adaptation of plants to pollen ***,this adaptation is less critical in short-lived *** evaluate pollen limitation and the plasticity of floral longevity to pollination in Potentilla tanacetifolia,a gynodioecious herb with short-lived flowers,we analyzed its breeding system,tested sex-differential pollen limitation,and compared variations in floral display size in natural populations in Duolun County,Inner Mongolia,*** pollination experiments and pollinator exclusion treatments revealed that *** is self-compatible and non-autonomously apomictic and shows sex-differential pollen *** plasticity of floral longevity to pollination was observed;the floral duration of female plants was prolonged by approximately 3-4 hours with pollination exclusion ***,the percentage of flowers displayed on female plants during pollination exclusion treatment was significantly higher than that during natural *** natural pollination conditions,the percentage of flowers displayed on female plants was significantly higher than on hermaphrodite ***,approximately 50%of the pollen grains spread out of the anthers of hermaphrodite flowers within 2.h of anthesis;the number of pollen grains adhering to the stigmas of hermaphrodite flowers was significantly higher than that adhering to female flowers when flowers shed their *** results indicate that variation in floral longevity may be an adaptive strategy to pollination conditions for gynodioecious ***.

关键词： floral longevity gynodioecy plasticity pollen limitation Potentilla tanacetifolia.

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ON THE ERROR ESTIMATE OF LINEAR FINITE ELEMENT APPROXIMATION TO THE ELASTIC CONTACT PROBLEM WITH CURVED CONTACT BOUNDARY

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Journal of Computational Mathematics 2000年第6期18卷 561-566页

作者： Lie-heng Wang (state key {2. of Scientific and Engineering Computing, Institute of Computational Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, china) 中科院计算数学所科学与工程计算国家重点实验室北京 100080

In this paper, the linear finite element approximation to the elastic contact problem with curved contact boundary is considered. The error bound O(h[sup ?]) is obtained with requirements of two times continuously differentiable for contact boundary and the usual regular triangulation, while *** et. al. Obtained the error bound O(h[sup ?]) with requirements of three times continuously differentiable for contact boundary and extra regularities of triangulation (c.f. [2.). [ABSTRACT FROM AUTHOR]

关键词： contact problem finite element approximation

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Image of local energy anomaly during a heavy rainfall event

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chinese Physics B 2017年第11期26卷 565-573页

作者：杨帅左群杰高守亭 laboratory of Cloud-Precipitation Physics and severe Storms (LACS) Institute of Atmospheric PhysicsChinese Academy of Sciences state key {2. of severe weather Chinese Academy of Meteorological Sciences

A clear and interesting image of local total energy anomaly(EA) is depicted for a heavy rainfall event in this *** the convection development, it exhibits a positive local EA, implying local total energy(TE) experiences heaping up to prepare for the future system development. As the convection grows, it transforms into an opposite spatial modality with negative EA dominant, which means that the local TE is consumed to feed the convection growth in the middle and lower levels. The local total EA has consistent variation regular in intensity with severe weather system evolution. By utilizing the local TE budget equation in variable density fluid, the flux divergence of energy and its components are investigated, which could account for the local TE variation better. To relax the restriction and complexity introduced by identifying sporadic and alternative positive/negative signals of EA, the method taking the absolute-value operator on energy flux divergence is used to further simplify analyses. The derived characteristic signal of absolute EA is clearer and cleaner than ***, the EA could be illustrated based on the active degree of energy supply/consumption in a generalized sense whatever positive or negative anomaly should be it, which could be used easily to identify and even predict the system development for operational application. Note that, although two sets of methodologies are used to define EA herein, they play absolutely different roles in nature throughout the whole context. For example, the taking-perturbation method provides a diagnostic tool to portray a preliminary sketch and to give sufficient necessity of this research, while tendency equation of local TE illuminates more predictive sense and accounts for future local EA related to following system evolution. Therefore, the latter could be a more effective tool to routine usage.

关键词： local energy anomaly energy budget equation heavy rainfall

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

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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 {2. 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 {2. 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 {2. 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 {2. Beijing China state key {2. 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 {2. of Nonlinear Mechanics, Institute of Mechanics, chinese academy of sciences, beijing 100080, china state key {2. of Scientific and Engineering Computing, Institute of Computational Mathematics, chinese academy of sciences, beijing 100080, china state key {2. of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing China state key {2. 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 1:2. (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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Confirmation of a natural hybrid species in Petrocosmea(Gesneriaceae) based on molecular and morphological evidence

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Journal of Systematics and Evolution 2011年第5期49卷 449-463页

作者： 1,3~Zhi-Jing QIU 2.Zu-Li YUAN 1~Zhen-Yu LI 1~Yin-Zheng WANG 1(state key {2. of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,beijing 100093,china) 2.Henan Agricultural University,Zhengzhou 45002.china) 3(Graduate School of the chinese academy of sciences,beijing 100049,china) (state key {2. of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate School of the chinese academy of {2. Beijing 100049 China) (Henan Agricultural University Zhengzhou 45002 China)

A natural hybrid species in Petrocosmea named Longianthera in Yanshan County,Yunnan Province is confirmed for the first time based on molecular and morphological *** character count procedure of the variable characters show that Longianthera populations are characteristic of the intermediate morphological traits between its putative parents Yanshan and Petrocosmea *** nuclear ribosomal internal transcribed spacer region and three chloroplast regions of matK,trnL-F,and trnT-L are sequenced in the putative hybrid and the related *** alignment of DNA sequences and the phylogenetic trees could exclude all the other species in Petrocosmea as the parental species except for Yanshan and *** haplotypes in the 31 internal transcribed spacer sequences and six haplotypes in 42.cpDNA sequences were found from 14 individuals of Longianthera *** analyses of DNA sequences,haplotypes,and phylogenetic trees indicate that Longianthera is likely a hybrid species between its putative parents Yanshan and ***,in which Yanshan might be the most possible maternal *** factors may contribute to the natural hybridization between these two parental species in Petrocosmea,such as the overlapped geographic distribution,habitats,flowering periods,and shared ***,the new species of Yanshan and the natural hybrid species of Longianthera are described.

关键词： chloroplast DNA Gesneriaceae ITS morphology natural hybridization Petrocosmea.

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Evolution of desertification in a two-dimensional energy balance model coupled with thermodynamics and dynamics

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Science china Earth sciences 2010年第11期53卷 1726-1733页

作者： CHAO JiPing1,2.& LI YaoKun3,4 1National Marine Environmental Forecasting Center, beijing 100081, china 2.irst Institute of Oceanography, {2. Oceanic Administration, Qingdao 2.6061, china 3{2. key laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics, Institute of Atmospheric Physics, chinese academy of sciences, beijing 10002., china 4Graduate University of chinese academy of sciences, beijing 100049, china National Marine Environmental Forecasting Center Beijing China First Institute of Oceanography State Oceanic Administration Qingdao China state key {2. 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 {2. Beijing China

The relationship between desert evolution and change in albedo has been investigated quasi-analytically using a zonal mean two-dimensional energy balance model which considers the radiation transmission process due to thermodynamics and bound- ary layer movement caused by kinetics. A climate state including temperature, zonal wind, meridional wind and vertical wind can be simulated according to the current zonal distribution of albedo. Given desert distribution, characterized by the value and distribution of albedo, the response of climate on albedo has been studied to analyze the evolution of desert climate. One significant result is that the simple model can reproduce mean meridional circulation. Another result indicates that climate corresponds to two equilibria. This happens when the junction temperature between vegetation and desert is higher than a certain critical value. As for the first equilibrium, the desert belt is predicted to move southward in the northern hemisphere with the increasing values of albedo, which corresponds to the current trend of climate change. For the second equilibrium, vegetation will expand northward with increasing values of albedo, which would indicate a narrowing of the desert belt. In order to determine if the two equilibria exist, new physical models are needed.

关键词： two-dimensional energy balance model desertification two equilibria

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Cotton pixel identification with CBERS-02.CCD data based on spectral knowledge

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Science china(Technological sciences) 2005年第S2期48卷 129-144页

作者： LI Jing1,2.3, LIU Qinhuo1,3, LIU Qiang1, CHEN Liangfu1, BO Junhua3 & LI Shaokun3 1. state key {2. of Remote Sensing Science, IRSA, chinese academy of sciences, beijing 100101, china 2. Graduate University of chinese academy of sciences, beijing 100049, china 3. The key Oasis Eco-agriculture {2. of Xinjiang Production and Construction Corps, Shi Hezi 832.00, china state key {2. of Remote Sensing Science IRSA Chinese Academy of Sciences Beijing 100101 China Graduate University Chinese Academy of Sciences Beijing 100049 China key Oasis Eco-agriculture laboratory Xinjiang Production and Construction Corps. Shi Hezi 832000 China

In this paper the in-situ experiment data are collected from the Spectral Library to estimate the possible values of the primary structural parameters in each cotton growing season by statistics. Based on these values the spectra of the cotton major growing seasons were simulated and analyzed using the canopy reflectance model, SAILH. In this way we also simulated the cotton pixel spectra corresponding to CBERS-02.CCD and took them as the reference spectra for spectra fitting. Then No.143 Regiment of No.8 Agricultural Division of Xinjiang Production and Construction Corps (XPCC) was chosen as the study area, and two spectra fitting methods, Mahalanobis distance and spectra angle, were used to identify cotton pixel from CBERS-02.CCD image of the study area. At last we analyzed the effect of the calibration coefficients error on cotton identifying. The results showed that within 4% error the spectral angle classifier can still have a good performance.

关键词： CBERS-02 cotton pixel identification spectra fitting.

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Quantum threshold group signature

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Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1505-1514页

作者： YANG YuGuang1,2.3 & WEN QiaoYan4 1 College of Computer Science and Technology, beijing University of Technology, beijing 10012., {2. 2.state key laboratory of Integrated Services Network, Xidian University, Xi’an 710071, {2. 3 state key laboratory of Information Security (Graduate University of chinese academy of {12.), beijing 100049, {2. 4 state key laboratory of Networking and Switching Technology, beijing University of Posts and Tele-communications, beijing 100876, {2. College of Computer Science and Technology Beijing University of Technology Beijing China state key {2. of Integrated Services Network Xidian University Xi’an China state key {2. of Information Security Graduate University of Chinese Academy of Sciences Beijing China state key {2. of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China

In most situations, the signer is generally a single person. However, when the message is written on behalf of an organization, a valid message may require the approval or consent of several persons. Threshold signature is a solution to this problem. Generally speaking, as an authority which can be trusted by all members does not exist, a threshold signature scheme without a trusted party appears more attractive. Following some ideas of the classical Shamir’s threshold signature scheme, a quantum threshold group signature one is proposed. In the proposed scheme, only t or more of n persons in the group can generate the group signature and any t-1 or fewer ones cannot do that. In the verification phase, any t or more of n signature receivers can verify the message and any t-1 or fewer receivers cannot verify the validity of the signature.

关键词： threshold quantum signature trusted party quantum cryptography

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Direct numerical simulation of shock/turbulent boundary layer interaction in a supersonic compression ramp

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1651-1658页

作者： LI XinLiang1,FU DeXun2.MA YanWen2.& LIANG Xian1 1 key laboratory of High Temperature Gas Dynamics,Institute of Mechanics,{2. academy of sciences,beijing 100190,china 2.The state key laboratory of Nonlinear Mechanics,Institute of Mechanics,{2. academy of sciences,beijing 100190,china key laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of Sciences Beijing China The state key {2. of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing China

A direct numerical simulation of the shock/turbulent boundary layer interaction flow in a supersonic 2.-degree compression ramp is conducted with the free stream Mach number *** blow-and-suction disturbance in the upstream wall boundary is used to trigger the *** the mean wall pressure and the velocity profiles agree with those of the experimental data,which validates the *** turbulent kinetic energy budget in the separation region is *** show that the turbulent production term increases fast in the separation region,while the turbulent dissipation term reaches its peak in the near-wall *** turbulent transport term contributes to the balance of the turbulent conduction and turbulent *** on the analysis of instantaneous pressure in the downstream region of the mean shock and that in the separation bubble,the authors suggest that the low frequency oscillation of the shock is not caused by the upstream turbulent disturbance,but rather the instability of separation bubble.

关键词： compression ramp shock/turbulent boundary layer interaction direct numerical simulation shock oscillation

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