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Assembly of plant communities in coastal wetlands--the role of saltcedar Tamarix chinensis during early succession

Journal of Plant Ecology 2015年第5期8卷 539-548页

作者： Meng Gao Xinxiu Wang cang hui Huapeng Yi Chuanqi Zhang xiaoqing Wu xiaoli Bi Yong Wang Luxiang xiao De Wang Yantai Institute of Coastal Zone Research Chinese Academy of SciencesNo.17 Chunhui RoadLaishan DistrictYantai 264003China University of Chinese Academy of Sciences No.19 Yuquan RoadShijingshan DistrictBeijing 100049China Department of Mathematical Sciences Centre for Invasion BiologyStellenbosch UniversityMatieland 7602South Africa Mathematical and Physical Biosciences African Institute for Mathematical SciencesMuizenberg 7945South Africa Institute of Geography and Planning Ludong UniversityNo.186Hongqi RoadZhifu DistrictYantai 264025China

Aims The mechanisms of plant community assembly are hypothesized to vary at different stages of ***,we explore the local assemblage structure of a herbaceous plant community at its early stage of succession in a supratidal ***,we assess the role of Chinese saltcedar(Tamarix chinensis),the lone dominant shrub species,in shaping the spatial structure and species composi-tion in the local plant community,after landscape *** We used the multivariate trend-surface analysis for analyzing the spatial structure of the community composition.a null model was also used to detect potential biotic interactions between *** significance was derived from a permutation test by randomizing the presence-absence matrix and functional traits *** analysis by randomly selecting 50 subplots and repeating the null model tests was also ***,rank correlation analysis was used to study the relationship between effect sizes and distance to nearest *** *** Findings The herbaceous plant community was highly structured and shaped by the presence of *** local scale,two functional traits,plant height and leaf area,were found to be significantly ***,environmental stress and interspecific competition played a trivial effect on the local community *** facilitating effect of *** on the pioneering herbaceous plants,through acting as a wind shelter,was put forward as the dominant community assembly process.

关键词： supratidal wetland functional traits spatial structure trait convergence facilitative effect wind sheltering

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Bayesian Rayleigh wave inversion with an unknown number of layers

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Earthquake Engineering and Engineering Vibration 2020年第4期19卷 875-886页

作者： Ka-Veng Yuen xiao-hui Yang State Key Laboratory of Internet of Things for Smart City and Department of Civil and Environmental Engineering University of Macao999078MacaoChina

Surface wave methods have received much attention due to their efficient, flexible and convenient characteristics. However, there are still critical issues regarding a key step in surface wave inversion. In most existing methods, the number of layers is assumed to be known prior to the process of inversion. However, improper assignment of this parameter leads to erroneous inversion results. A Bayesian nonparametric method for Rayleigh wave inversion is proposed herein to address this problem. In this method, each model class represents a particular number of layers with unknown S-wave velocity and thickness of each layer. As a result, determination of the number of layers is equivalent to selection of the most applicable model class. Regarding each model class, the optimization search of S-wave velocity and thickness of each layer is implemented by using a genetic algorithm. Then, each model class is assessed in view of its efficiency under the Bayesian framework and the most efficient class is selected. Simulated and actual examples verify that the proposed Bayesian nonparametric approach is reliable and efficient for Rayleigh wave inversion, especially for its capability to determine the number of layers.

关键词： Bayesian model class selection generalized r/t coefficients algorithm genetic algorithm inversion of Rayleigh wave number of layers

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New indices to balanceα-diversity against tree size inequality

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Journal of Forestry Research 2024年第1期35卷 229-237页

作者： Li Zhang Brady K.Quinn cang hui Meng Lian Johan Gielis Jie Gao Peijian Shi College of Ecology and Environment Bamboo Research InstituteNanjing Forestry University159 Longpan RoadNanjing 210037People’s Republic of China Fisheries and Oceans Canada Andrews Biological Station125 Marine Science DriveSt.AndrewsNB E5B 0E4Canada Department of Mathematical Sciences Centre for Invasion BiologyStellenbosch UniversityMatieland 7602South Africa Mathematical and Physical Biosciences African Institute for Mathematical SciencesCape Town 7945South Africa Department of Biosciences Engineering University of AntwerpB-2020 AntwerpBelgium College of Life Science Xinjiang Normal University102 Xinyi RoadUrumqi 830054People’s Republic of China

The number and composition of species in a community can be quantified withα-diversity indices,including species richness(R),Simpson’s index(D),and the Shannon-Wiener index(H΄).In forest communities,there are large variations in tree size among species and individu-als of the same species,which result in differences in eco-logical processes and ecosystem ***,tree size inequality(TSI)has been largely neglected in studies using the available diversity *** TSI in the diameter at breast height(DBH)data for each of 99920 m×20 m forest census quadrats was quantified using the Gini index(GI),a measure of the inequality of size *** generalized performance equation was used to describe the rotated and right-shifted Lorenz curve of the cumulative proportion of DBH and the cumulative proportion of number of trees per *** also examined the relationships ofα-diversity indices with the GI using correlation *** generalized performance equation effectively described the rotated and right-shifted Lorenz curve of DBH distributions,with most root-mean-square errors(990 out of 999 quadrats)being<*** were significant positive correlations between each of threeα-diversity indices(i.e.,R,D,and H’)and the ***,the total abundance of trees in each quadrat did not significantly influence the *** means that the TSI increased with increasing spe-cies ***,two new indices are proposed that can balanceα-diversity against the extent of TSI in the com-munity:(1−GI)×D,and(1−GI)×H’.These new indices were significantly correlated with the original D and H΄,and did not increase the extent of variation within each group of *** study presents a useful tool for quantifying both species diversity and the variation in tree sizes in forest communities,especially in the face of cumulative species loss under global climate change.

关键词： Diameter at breast height(DBH) Gini index Shannon-Wiener index Simpson’s index Quadrat Tree size

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Deterministic nondestructive state analysis for polarization-spatial-time-bin hyperentanglement with cross-Kerr nonlinearity

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Chinese Physics B 2021年第3期30卷 176-182页

作者： hui-Rong Zhang Peng Wang Chang-Qi Yu Bao-cang Ren Department of Physics Capital Normal UniversityBeijing 100048China

We present a deterministic nondestructive hyperentangled Bell state analysis protocol for photons entangled in three degrees of freedom(DOFs),including polarization,spatial-mode,and time-bin *** polarization Bell state analyzer and spatial-mode Bell state analyzer are constructed by polarization parity-check quantum nondemolition detector(P-QND)and spatial-mode parity-check quantum nondemolition detector(S-QND)using cross-Kerr nonlinearity,*** time-bin Bell state analyzer is constructed by the swap gate for polarization state and time-bin state of a photon(P-T swap gate)and *** Bell states analyzer for one DOF will not destruct the Bell states of other two DOFs,so the polarization-spatial-time-bin hyperentangled Bell states can be determinately distinguished without *** deterministic nondestructive state analysis method has useful applications in quantum information protocols.

关键词： quantum communication deterministic nondestructive state analysis polarization-spatial-time-bin hyperentanglement

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Gene expression alteration during redox-dependent enhancement of arsenic cytotoxicity by emodin in HeLa cells

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Cell Research 2005年第7期15卷 511-522页

作者： xiao Jing WANG, Jie YANG, hui cang, Yan Qiong ZOU, Jing YI*Department of Cell Biology, Shanghai Second Medical University, 280 Chongqing Road, Shanghai 200025, China Department of Cell Biology Shanghai Second Medical University Shanghai China

Emodin (1,3,8-trihydroxy-6-methylanthraquinone) could enhance the sensitivity of tumor cells to arsenic trioxide(As2O3)–induced apoptosis via generation of ROS, but the molecular mechanism has not been elucidated. Here, wecarried out cDNA microarray-based global transcription profiling of HeLa cells in response to As2O3/emodin cotreatment,comparing with As2O3–only treatment. The results showed that the expression of a number of genes was substantiallyaltered at two time points. These genes are involved in different aspects of cell function. In addition to redox regulationand apoptosis, ROS affect genes encoding proteins associated with cell signaling, organelle functions, cell cycle,cytoskeleton, etc. These data suggest that based on the cytotoxicity of As2O3, emodin mobilize every genomic resourcethrough which the As2O3–induced apoptosis is facilitated.

关键词： microarray reactive oxygen species apoptosis arsenic trioxide emodin.

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Insider Trading with a Random Deadline under Partial Observations:Maximal Principle Method

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Acta Mathematicae Applicatae Sinica 2022年第4期38卷 753-762页

作者： Kai xiao Yong-hui ZHOU School of Mathematical Sciences Guizhou Normal UniversityGuiyang 550001China School of Big Data and Computer Science Guizhou Normal UniversityGuiyang 550001China

For a revised model of Caldentey and Stacchetti(Econometrica,2010)in continuous-time insider trading with a random deadline which allows market makers to observe some information on a risky asset,a closed form of its market equilibrium consisting of optimal insider trading intensity and market liquidity is obtained by maximum principle *** shows that in the equilibrium,(i)as time goes by,the optimal insider trading intensity is exponentially increasing even up to infinity while both the market liquidity and the residual information are exponentially decreasing even down to zero;(ii)the more accurate information observed by market makers,the stronger optimal insider trading intensity is such that the total expect profit of the insider is decreasing even go to zero while both the market liquidity and the residual information are decreasing;(iii)the longer the mean of random time,the weaker the optimal insider trading intensity is while the more both the residual information and the expected profit are,but there is a threshold of trading time,half of the mean of the random time,such that if and only if after it the market liquidity is increasing with the mean of random time increasing.

关键词： continuous-time insider trading random deadline partial observations filtering theory maximal principle

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Theoretical Studies on the Ground State and Excited State of 2,7′- （Ethylene）-bis-8-hydroxyquinoline

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Chinese Journal of Chemical Physics 2008年第3期21卷 263-269页

作者： hui-xue Li Su-juan Pan xiao-feng Wang Tai xiao Biochemical College of Tianshui Normal University Tianshui 741000 China College of Chemical Engineering Northwest Normal University Lanzhou 730070 China

2,7′-（Ethylene）-bis-8-hydroxyquinoline was optimized with DFT/B3LYP and ab initio HF methods, so ion- ization potential and electron affinity could be determined. Absorption spectrum was calculated by ZINDO and TD-DFT. CIS method was used to calculate the S1 excited states of the compound and afterwards the emission spectrum was computed. When the solvent effect was taken into account, the computed results show encouraging agreement with known experimental data. The results of analyzing the relationship between the energies and absorption spectra indicate that the ability to transporting electrons is strengthened compared with 8-hydroxyquinoline and that absorption and emission spectra are red-shifted. The intramoleeular reor- ganization energy of tris（2,7′-（ethylene）-bis-8-hydroxyquinoline）-aluminum implies its electron transporting property is worse than tris（8-hydroxyquinoline）-aluminum. The predicted maximum emission wavelength is red-shifted compared with tris（8-hydroxyquinoline）-aluminum.

关键词： 2,7′(Ethylene)-bis-8-hydroxyquinoline Absorption spectrum Emission spectrum Densityfunctional theory

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SYMMETRY IN WORLD TRADE NETWORK

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Journal of Systems Science & Complexity 2009年第2期22卷 280-290页

作者： hui WANG Guangle YAN Yanghua xiao Business School University of Shanghai for Science and Technology Shanghai 200093 China. Department of Computing and Information Technology Fudan University Shanghai 200433 China.

ymmetry of the world trade network provides a novel perspective to understand the world-wide trading system. However, symmetry in the world trade network （WTN） has been rarely studied so far. In this paper, the authors systematically explore the symmetry in WTN. The authors construct WTN in 2005 and explore the size and structure of its automorphism group, through which the authors find that WTN is symmetric, particularly, locally symmetric to a certain degree. Furthermore, the authors work out the symmetric motifs of WTN and investigate the structure and function of the symmetric motifs, coming to the conclusion that local symmetry will have great effect on the stability of the WTN and that continuous symmetry-breakings will generate complexity and diversity of the trade network. Finally, utilizing the local symmetry of the network, the authors work out the quotient of WTN, which is the structural skeleton dominating stability and evolution of WTN.

关键词： Automorphism group network quotients symmetry world trade network.

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The hydrodynamic interactions of an array of truncated circular cylinders as each cylinder oscillates independently with different prescribed modes

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Journal of Hydrodynamics 2013年第1期25卷 27-38页

作者： ZENG xiao-hui TANG Si-yi Institute of Mechanics Chinese Academy of Sciences

An analytical method based on the eigenfunction expansion and the Graf＇s addition theorem for Bessel functions is developed to study the hydrodynamic interactions of an array of truncated circular cylinders with each cylinder oscillating independently in different prescribed modes. The hydrodynamic radiation and diffraction of linear waves by such an array of cylinders are investigated and the analytical solutions of the velocity potentials are obtained. After comparisons for degenerated cases and program verifications, several cases for an array of truncated cylinders with each cylinder oscillating independently in surge, sway, heave, roll, and pitch modes with different prescribed amplitudes, are studied and the hydrodynamic forces and moments acting on the cylinders are obtained.

关键词： array of truncated circular cylinders independent oscillation radiation hydrodynamic interaction

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Heteroscedastic regression analysis method for mixed data

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航空动力学报 2011年第4期26卷 721-726页

作者： FU hui-min YUE xiao-rui Research Center of Small Sample Technology Beijing University of Aeronautics and Astronautics Beijing 100191 China

The heteroscedastic regression model was established and the heteroscedastic regression analysis method was presented for mixed data composed of complete data,type-Ⅰ censored data and type-Ⅱ censored data from the location-scale *** best unbiased estimations of regression coefficients,as well as the confidence limits of the location parameter and scale parameter were ***,the point estimations and confidence limits of percentiles were ***,the traditional multiple regression analysis method which is only suitable to the complete data from normal distribution can be extended to the cases of heteroscedastic mixed data and the location-scale *** the presented method has a broad range of promising applications.

关键词： heteroscedastic regression analysis censored data performance test life prediction reliability analysis

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