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High genetic diversity in the endangered and narrowly distributed amphibian species Leptobrachium leishanense

Integrative Zoology 2015年第5期10卷 465-481页

作者： Wei ZHANG Zhenhua LUO Mian ZHAO hua wu Institute of Evolution and Ecology International Research Centre of Ecology and EnvironmentSchool of Life SciencesCentral China Normal UniversityWuhanChina

Threatened species typically have a small or declining population size,which make them highly susceptible to loss of genetic diversity through genetic drift and *** diversity determines the evolutionary potential of a species;therefore,maintaining the genetic diversity of threatened species is essential for their *** this study,we assessed the genetic diversity of the adaptive major histocompatibility complex(MHC)genes in an endangered and narrowly distributed amphibian species,Leptobrachium leishanense in Southwest *** compared the genetic variation of MHC class I genes with that observed in neutral markers(5 microsatellite loci and cytochrome b gene)to elucidate the relative roles of genetic drift and natural selection in shaping the current MHC polymorphism in this *** found a high level of genetic diversity in this population at both MHC and neutral markers compared with other threatened amphibian *** positive selection was evident in the MHC class I *** higher allelic richness in MHC markers compared with that of microsatellite loci suggests that selection rather than genetic drift plays a prominent role in shaping the MHC variation pattern,as drift can affect all the genome in a similar way but selection directly targets MHC *** demographic analysis revealed no recent bottleneck events in ***,additional population decline will accelerate the dangerous status for this *** suggest that the conservation management of *** should concentrate on maximizing the retention of genetic diversity through preventing their continuous population *** their living habitats and forbidding illegal hunting are the most important measures for conservation of ***.

关键词： demography process genetic diversity major histocompatibility complex natural selection Leptobrachium leishanense

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Female-biased Dispersal of the Emei Moustache Toad (Leptobrachium boringii) under Local Resource Competition

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Asian Herpetological Research 2019年第1期10卷 24-31页

作者： Wenxia WANG Shichao WEI Mengjiao CHEN hua wu Institute of Evolution and Ecology School of Life Sciences Central China Normal University

Dispersal is an important area of ecological and evolutionary *** many studies have been conducted in mammals and birds,dispersal pattern in amphibians is still *** verify dispersal patterns of amphibians,an endangered species the Emei Moustache Toad(Leptobrachium boringii)was *** this study,we analyzed six genetic parameters:inbreeding coefficient(F_(IS)),gene diversity(H_S),the mean of corrected assignment index(mAI_C),the variance of corrected assignment index(vAI_C),relatedness(r)for all three years together and each year separately based on eight highly polymorphic microsatellite *** in totaled across years and each year for 581 individuals captured during 2013–2015 revealed a significant female-biased dispersal *** higher F_(IS) and H_S in females,and lower mAI_C and r for each year separately in females support that *** displays femalebiased dispersal,although r for the total dataset and vAI_C tests did not show significant differences between the ***-biased dispersal patterns may be explained by the local resource competition hypothesis.

关键词： Leptobrachium boringii microsatellite DNA female-biased dispersal the local resource competition hypothesis

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Energy efficiency of virtual MIMO transmission schemes for cluster-based wireless sensor networks

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 31-38页

作者： DING Jie LIU Dan-pu wu hua-ri Key Laboratory of Universal Wireless Communication Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China Beijing Academy of Agriculture and Forestry Sciences Beijing 100097 China

In this paper, a cluster-based virtual multiple-input multiple-output （MIMO） transmission architecture is proposed for energy-constrained wireless sensor networks. In the proposed architecture, instead of using cluster members as cooperative nodes, multiple cluster heads cooperate to form virtual antenna array so that MIMO transmission can be implemented. According to the MIMO techniques used in this architecture, two different schemes, vertical Bell Laboratories layered space-time （V-BLAST） based cluster heads cooperative transmission （VCHCT） and space time block code （STBC） based cluster heads cooperative transmission （SCHCT）, are developed. Based on the communication energy consumption model, theoverall energy consumption model for both VCHCT and SCHCT are derived. Detailed comparison between these two schemes and the original low-energy adaptive clustering hierarchy （LEACH） is performed to investigate the performance of these two schemes. Simulation results not only verify the theoretical analysis but also show that the two schemes have their specific application scenarios. When the sink is far from the sensor area, SCHCT scheme is much more energy efficient than LEACH and VCHCT scheme even if it consumes additional inter-cluster communication energy. When the distance to sink is near the sensor area, VCHCT is preferable.

关键词： energy efficiency MIMO STBC V-BLAST wireless sensor networks

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Viewpoint Optimization Using Genetic Algorithm for Flying Robot Inspection of Electricity Transmission Tower Equipment

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Chinese Journal of Electronics 2014年第2期23卷 426-431页

作者： YANG Guotian DONG Ruifang wu hua LIU Chang'an School of Control and Computer Engineering North China Electric Power University

To fully exploit the limited flight-time of the flying robot, and ensure the successful visibility of target, viewpoint optimization is proposed in this paper for the inspection of electricity transmission tower equipment with an optimization function to determine the best viewpoints in a local viewpoint region. The local viewpoint regions are generated from the local objective regions which are determined by the geometrical structure of a priori3 D model for the electricity transmission tower *** optimization function is structured based on three factors including visibility, viewing quality and observation distance. In addition, the fitness function of genetic algorithm is used to find the optimal viewpoint. The experimental results demonstrate the effectiveness and efficiency of the proposed viewpoint selection algorithm.

关键词： Flying robot inspection Electricity transmission tower equipment Viewpoint optimization Genetic algorithm 3D model

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Allelic Polymorphism,Gene Duplication and Balancing Selection of MHC Class ⅡB Genes in the Omei Treefrog(Rhacophorus omeimontis)

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Asian Herpetological Research 2016年第1期7卷 1-11页

作者： Li huaNG Mian ZHAO Zhenhua LUO hua wu Institute of Evolution and Ecology International Research Centre of Ecology and EnvironmentSchool of Life SciencesCentral China Normal University

The worldwide declines in amphibian populations have largely been caused by infectious fungi and bacteria. Given that vertebrate immunity against these extracellular pathogens is primarily functioned by the major histocompatibility complex（MHC） class Ⅱ molecules, the characterization and the evolution of amphibian MHC class Ⅱ genes have attracted increasing attention. The polymorphism of MHC class Ⅱ genes was found to be correlated with susceptibility to fungal pathogens in many amphibian species, suggesting the importance of studies on MHC class Ⅱ genes for amphibians. However, such studies on MHC class Ⅱ gene evolution have rarely been conducted on amphibians in China. In this study, we chose Omei treefrog（Rhacophorus omeimontis）, which lived moist environments easy for breeding bacteria, to study the polymorphism of its MHC class Ⅱ genes and the underlying evolutionary mechanisms. We amplified the entire MHC class ⅡB exon 2 sequence in the R. omeimontis using newly designed primers. We detected 102 putative alleles in 146 individuals. The number of alleles per individual ranged from one to seven, indicating that there are at least four loci containing MHC class ⅡB genes in R. omeimontis. The allelic polymorphism estimated from the 102 alleles in R. omeimontis was not high compared to that estimated in other anuran species. No significant gene recombination was detected in the 102 MHC class ⅡB exon 2 sequences. In contrast, both gene duplication and balancing selection greatly contributed to the variability in MHC class ⅡB exon 2 sequences of R. omeimontis. This study lays the groundwork for the future researches to comprehensively analyze the evolution of amphibian MHC genes and to assess the role of MHC gene polymorphisms in resistance against extracellular pathogens for amphibians in China.

关键词： MHC class ⅡB polymorphism gene duplication balancing selection Rhacophorus omeimontis

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Zm HAK5 and Zm HAK1 function in K^+ uptake and distribution in maize under low K^+ conditions

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Journal of Integrative Plant Biology 2019年第6期61卷 691-705页

作者： Ya-Juan Qin Wei-hua wu Yi Wang State Key Laboratory of Plant Physiology and Biochemistry (SKLPPB) College of Biological SciencesChina Agricultural UniversityBeijing 100193China Center for Crop Functional Genomics and Molecular Breeding China Agricultural UniversityBeijing 100193China

Potassium (K^+) is an essential macronutrient for plant growth and development. Transporters from the KT/HAK/KUP family play crucial roles in K^+ homeostasis and cell growth in various plant species. However, their physiological roles in maize are still unknown. In this study, we cloned ZmHAKs and ZmHAKi and investigated their functions in maize (Zea mays L.). In situ hybridization showed that ZmHAKs was mainly expressed in roots, especially in the epidermis, cortex, and vascular bundle. ZmH AK5 was characterized as a high-affinity K^+ transporter. Loss of function of ZmHAK5 led to defective K^+ uptake in maize, under low K^+ conditions, whereas ZmHAK5-over-expressing plants showed increased K^+ uptake activity and improved growth. ZmHAKi was upregulated under low K^+ stress, as revealed by RT-qPCR. ZmHAKi mediated K^+ uptake when heterologously expressed in yeast, but its transport activity was weaker than that of ZmHAK5. Overexpression of ZmHAKi in maize significantly affected K^+ distribution in shoots, leading to chlorosis in older leaves. These findings indicate that ZmHAKs and ZmHAKi play distinct roles in K^+ homeostasis in maize, functioning in K^+ uptake and K^+ distribution, respectively. Genetic manipulation of ZmHAK5 may represent a feasible way to improve K^+ utilization efficiency in maize.

关键词： ZmHAK5 and ZmHAK1 function in K^+uptake and distribution in maize under low K^+conditions^FA ZmHAK5 and ZmHAK1 function in K^+uptake distribution

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Ruin Probabilities of a Surplus Process Described by PDMPs

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Acta Mathematicae Applicatae Sinica 2008年第1期24卷 117-128页

作者： Jing-min He Rong wu hua-yue Zhang Department of Mathematics and LPMC Nankai University Tianjin 300071 China

In this paper we mainly study the ruin probability of a surplus process described by a piecewise deterministic Markov process （PDMP）. An integro-differential equation for the ruin probability is derived. Under a certain assumption, it can be transformed into the ruin probability of a risk process whose premiums depend on the current reserves. Using the same argument as that in Asmussen and Nielsen, the ruin probability and its upper bounds are obtained. Finally, we give an analytic expression for ruin probability and its upper bounds when the claim-size is exponentially distributed.

关键词： Ruin probability piecewise deterministic Markov process integro-differential equation volterra equation

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A Modified Integral Global Optimization Method and Its Asymptotic Convergence

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Acta Mathematicae Applicatae Sinica 2009年第2期25卷 283-290页

作者： Zheng Peng Ya-jun Shen Dong-hua wu Department of mathematics Nanjing University Nanjing 210093 China Department of mathematics Shanghai University Shanghai 200444 China

In this paper, we propose a new integral global optimization algorithm for finding the solution of continuous minimization problem, and prove the asymptotic convergence of this algorithm. In our modified method we use variable measure integral, importance sampling and main idea of the cross-entropy method to ensure its convergence and efficiency. Numerical results show that the new method is very efficient in some challenging continuous global optimization problems.

关键词： Continuous global optimization modified integral global optimization method asymptotic convergence

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Strong Mixing Subshift of Finite Type and Hausdorff Measure of Its Chaotic Set

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Acta Mathematica Sinica,English Series 2011年第4期27卷 789-798页

作者： Wan Gan SONG Zhi HU hua Ming wu School of Mathematical Science Peking University Beijing 100871 P. R. China School of Computer Science and Technology Huaibei Coal Industry Teachers Huaibei 235000 P. R. China School of Mathematical and Computer Science Zhanjiang Teachers College Zhanjiang 524048 P. R. China

We present a sufficient and necessary condition for the subshift of finite type to be a measure-preserving transformation or to be a strong mixing measure-preserving transformation with respect to the Hausdorff measur... 详细信息

关键词： Symbolic space a finite subshift chaotic set Hausdorff measure

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Synthesis of Ti_3AlC_2 by SHS and thermodynamic calculation based on first principles

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Rare Metals 2015年第2期34卷 107-110页

作者： Chun-Cheng Zhu Jia Zhu hua wu Hong Lin College of Chemistry and Chemical Engineering Harbin Normal University

In this paper, a self-propagating high-temperature combustion synthesis with the pseudo-hot isostatic pressing process（SHS/PHIP） was employed to fabricate high-pure Ti_3AlC_2（φ 240 mm）. In addition, the first principle with quasi-harmonic approximation was applied for the thermodynamic properties＇ investigation of Ti_2AlC and Ti_3AlC_2, including Gibbs free energy, enthalpy, and *** temperature increasing, Gibbs free energy increases,but enthalpy and entropy decrease. The present work provides the theoretical proof for the synthesis mechanism of Ti_3AlC_2 by SHS/PHIP.

关键词： Ti_3AlC_2 Combustion synthesis Thermodynamics

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