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Molecular Population Genetics of Rice Domestication

Journal of Integrative Plant Biology 2007年第6期49卷 769-775页

作者： tian Tang Suhua shi State Key Laboratory of Biocontrol School of Life Sciences Sun Yat-sen (Zhongshan) University Guangzhou 510275 China

Domestication is a selection process that genetically modifies species to meet human needs. A most intriguing feature of domestication is the extreme phenotypic diversification among breeds. What could be the ultimate source of such genetic variations？ Another notable outcome of artificial selection is the reduction In the fitness of domesticated species when they live In the wild without human assistance. The complete sequences of the two subspecies of rice cultlvars provide an opportunity to address these questions. Between the two subspecies, we found much higher rates of non-synonymous （N） than synonymous （S） substitutions and the N/S ratios are higher between cultivars than between wild species. Most interestingly, substitutions of highly dissimilar amino acids that are deleterious and uncommon between natural species are disproportionately common between the two subspecies of rice. We suggest strong selection in the absence of effective recombination may be the driving force, which we called the domestication-associated Hill-Robertson effect. These hitchhiking mutations may contribute to some fitness reduction in cultivars. Comparisons of the two genomes also reveal the existence of highly divergent regions in the genomes. Haplotypes in these regions often form highly polymorphic linkage blocks that are much older than speciation between wild species. Genes from such regions could contribute to the differences between indica and japonica and are likely to be involved in the diversifying selection under domestication. Their existence suggests that the amount of genetic variation within the single progenitor species Oryza rufipogon may be insufficient to account for the variation among rice cultivars, which may come from a more inclusive gene pool comprising most of the A-genome wild species. Genes from the highly polymorphic regions also provide strong support for the Independent domestication of the two subspecies. The genomic variation in rice has revealing i

关键词： rice population genetics domestication artificial selection admixture.

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Novel Fault Diagnosis Scheme for HVDC System via ESO

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高电压技术 2007年第11期33卷 88-93页

作者： YAN Bing-yong tian Zuo-hua shi Song-jiao Department of Automation Shanghai Jiao Tong University Shanghai 200240 China

A novel fault detection and identification(FDI)scheme for HVDC(High Voltage Direct Current Transmission)system was *** was based on the unique active disturbance rejection concept,where the HVDC system faults were estimated using an extended states observer(ESO).Firstly,the mathematical model of HVDC system was constructed,where the system states and disturbance were treated as an extended *** augment HVDC system was established by using the extended state in rectify side and converter side,***,a fault diagnosis filter was established to diagnose the HVDC system faults via the ESO *** evolution of the extended state in the augment HVDC system can reflect the actual system faults and disturbances,which can be used for the fault diagnosis purpose.A novel feature of this approach is that it can simultaneously detect and identify the shape and magnitude of the HVDC faults and ***,different kinds of HVDC faults were simulated to illustrate the feasibility and effectiveness of the proposed ESO based FDI *** with the neural network based or support vector machine based FDI approach,the ESO based FDI scheme can reduce the fault detection time dramatically and track the actual system fault ***'s more important,it needs not do complex online calculations and the training of neural network so that it can be applied into practice.

关键词：高压直流输电系统故障检验与识别故障诊断分支状态观测器

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Econometric modeling of risk measures: A selective review of the recent literature

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Applied Mathematics(A Journal of Chinese Universities) 2019年第2期34卷 205-228页

作者： tian Ding-shi CAI Zong-wu FANG Ying Wang Yanan Institute for Studies in Economics Department of StatisticsSchool of EconomicsMinistry of Education Key Laboratory of Econometrics and Fujian Key Laboratory of Statistical ScienceXiamen UniversityXiamenFujian 361005China Department of Economics University of KansasLawrenceKS 66045USA

Since the financial crisis in 2008, the risk measures which are the core of risk management, have received increasing attention among economists and practitioners. In this review, the concentration is on recent developments in the estimation of the most popular risk measures, namely, value at risk (VaR), expected shortfall (ES), and expectile. After introducing the concept of risk measures, the focus is on discussion and comparison of their econometric modeling. Then, parametric and nonparametric estimations of tail dependence are investigated. Finally, we conclude with insights into future research directions.

关键词： Expectile Expected Shortfall Network Risk Nonparametric Estimation Tail Dependence Value at Risk

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Energy Consumption and Its Influencing Factors of Iron and Steel Enterprise

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Journal of Iron and Steel Research International 2013年第8期20卷 8-13页

作者： DU Tao shi tian LIU Yong YE Jian-bo State Environmental Protection Key Laboratory of Eco-Industry Northeastern University

Based on the theory of system energy-saving, a multilevel input-output computational model ot the iron and steel enterprise was established. And one example was calculated using this model to analyze the product energy value, the process of energy consumption and energy consumption per ton of steel of an iron and steel enterprise. The influences of factory layout, steel ratio and production structure are calculated and analyzed. The calculation example indicates that reasonable factory layout is helpful to reduce its transportation energy consumption, decrease loss of heat, improve product rate and reduce environmental contamination; ore to steel ratio and iron to steel ratio decrease at the same degree; the influence of ore to steel ratio on energy intensity per ton is less than that of iron to steel ratio. The lord process product structure has a certain effect on comprehensive energy consumption per ton of steel.

关键词： energy consumption product energy value input-output model influencing factor

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Wavy structures in compressible mixing layers

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Acta Mechanica Sinica 2013年第5期29卷 633-640页

作者： Jun Chen Xiao-tian shi Tie-Jin Wang Zhen-Su She State Key Laboratory for Turbulence and Complex Systems College of Engineering China Academy of Aerospace Aerodynamics

Semi-periodic structures namely inclined wavy structures （IWS） are experimentally observed in compressible mixing layers at two convective Mach numbers （Mc = 0.11 and 0.47）. Flow structures are visualized by the laserinduced planar laser Mie scattering （PLMS） technique. Two methods are developed to investigate the spatial distribu- tion and geometry of IWS：（1） the dominant mode extrac- tion （DME） method, to extract the dominant modes of IWS from the streamwise gray-level fluctuation, and （2） the phase tracking （PT） method, to identify the shape of IWS. The re- sults suggest that pressure perturbations account for the for- marion of IWS in the initial mixing region and the joint effect of dilatation and coherent vortices enhances IWS in the well- developed region. The large transverse （cross-flow） scale of the IWS and their relation to coherent vortices （CV） indicate that the disturbance originated from CV in the mixing center propagates far into the free streams. The DME and the PT method are shown to be the effective tools to study the geometrical features of wavy structures in compressible shear flows.

关键词： Compressible mixing layer. Growth rate. Visu- alization Structures Coherent vortex

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Interaction Between Cryptococcus laurentii,Monilinia fructicola,and Sweet Cherry Fruit at Different Temperatures

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Agricultural Sciences in China 2008年第1期7卷 48-57页

作者： WANG You-sheng tian shi-ping Beijing Key Laboratory of Plant Resources Research and Development Beijing Technology and Business University Beijing 100037 P.R. China Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 P.R.Chinu

The present study was performed mainly to investigate the antagonist-pathogen-host interaction in wounds of the sweet cherry fruits. The antagonistic yeast Cryptococcus laurentii could significantly reduce the brown rot of the sweet cherry fruit caused by Monilinia fructicola at 25 and 1 ℃. The populations of yeast increased faster in the presence of the pathogen initially, but then decreased rapidly. In the fruits inoculated with M. fructicola alone or combined with C. laurentii, an induction of lipid peroxidation as well as activities of the antioxidant enzymes, such as, superoxide dismutases （SOD）, catalase （CAT）, and peroxidase （POD）, was observed. The isoenzyme pattern of polypheno/oxidase （PPO） changed greatly after the symptoms appeared, with new PPO isoforms being induced. By contrast, the induction of lipid peroxidation and activities of SOD, CAT, and POD were low, although no significant changes were found in the PPO isoenzyms in the fruits inoculated with antagonist C. laurentii alone. The inhibition of brown rot during the antagonist- pathogen-host interaction in wounds of the sweet cherry fruits was mainly on account of the stimulated growth of C. laurentii as well as the induction of antioxidant enzymes of the fruits by M. fructicola.

关键词： Cryptococcus laurentii Monilinia fructicola sweet cherry interaction

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Discussion of Some Problems About Nonlinear Time Series Prediction Using v-Support Vector Machine

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Communications in Theoretical Physics 2007年第7期48卷 117-124页

作者： GAO Cheng-Feng CHEN tian-Lun NAN tian-shi Department of Physics,Nankai University,tianjin 300071,China Department of Physics Nankai University Tianjin 300071 China

Some problems in using v-support vector machine(v-SVM)for the prediction of nonlinear time series *** problems include selection of various net parameters,which affect the performance of prediction,mixtureof kernels,and decomposition cooperation linear programming v-SVM regression,which result in improvements of *** simulations in the prediction of nonlinear time series produced by Mackey-Glass equation andLorenz equation provide some improved results.

关键词： v-SVM nonlinear time series prediction

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Electrocatalytic Oxidation of Calcium Folinate on Carboxyl Graphene Modified CuxO/Cu Electrode

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Chinese Journal of Chemical Physics 2016年第6期29卷 729-734,I0002页

作者： Li-wen Wang Shou-guo Wu tian-yang shi Wei Wei Pan Pan Departmentol:Chemistry UniversityofScienceandTechnologyofChinaHefei230026China

Carboxyl graphene modified CuxO/Cu electrode was fabricated. The bare copper electrode was firstly anodic polarized in 1.0 mol/L NaOH solution in order to get CuxO nanoparticles, then the carboxyl graphene （CG） was electrodeposited on the CuxO/Cu electrode by cyclic potential sweeping. The electrocatalytic oxidation behaviors of calcium folinate （CF） at the graphene modified CuxO/Cu electrode were investigated by cyclic voltammetry. A positive scan polarization reverse catalytic voltammetry was used to obtain the pure catalytic oxidation current. The graphene modified CuxO/Cu electrode was served as the electrochemical sensor of CF, a highly sensitivity of 22.0μA.（μmol/μL）^-1cm^-2 was achieved, and the current response was linear with increasing CF concentration in the range of 2.0×10^-7 mol/L to 2.0×10^-5 mol/L, which crossed three orders of magnitude, and the detection limit was found 7.6×10^-5 mol/L （S/N=3）. In addition, the proposed sensor was successfully applied in determination of CF in drug sample.

关键词： Calcium folinate Carboxyl graphene CuxO/Cu electrode Chemically modi-fied electrode Positive scan polarization reverse catalytic voltammetry

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The Effect of Boron on the Properties of Glucomannan: An Experimental and Molecular Dynamics Simulation Study

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Chinese Journal of Structural Chemistry 2005年第12期24卷 1397-1402页

作者： PANG Jie SUN Yu-Jing LI Bin tian shi-Ping CHEN Shao-Jun College of Food Science Fu Jian Agriculture And Forestry University Fuzhou Fujian 350002 China Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany The Chinese Academy of Sciences Beijing 100093 China College of Food Science and Technology Agriculture University of Middle China Wuhan Hubei 430070 China

The effect of boron on the properties of Konjac Glucomanan （KGM） has been investigated by the method of experiment and molecular dynamic simulation. Upon analysis, the property and structure of KGM are apt to be affected by boron and structural reasons for property change were discussed. In detail, the addition low concentration borax can increase the systematic inherent viscosity, by contrast, high concentration borax has opposite effect on the viscosity. When adding borax, the micropores on KGM film surface decrease or disappear, leading to more compact and uniform on the film surface. The structure of KGM-Boron complex is described as the coordination reaction between KGM and boron. The main reaction points are hydroxyl group on C（6） position of sugar as well as those on C（2） and C（3） positions of mannose with two kinds of complexes formation： B-K2 and KB-K. And KB-K mainly consists of g-b-m.

关键词： glucomannan boron NMR molecular dynamics

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Calculation and Analysis of Internal Force in Arch Structure of Frozen Soil

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Journal of China University of Mining and Technology 2005年第4期15卷 279-282页

作者： YUE Feng-tian ZHANG Yong shi Rong-jian School of Architecture and Civil Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Aimed at the frozen soil arch reinforcement form of upside shed used for the shield machine launching in tunneling the internal force of the structure was calculated with the aid of the structural mechanics theory. Considering the space characteristics of the structure, this calculating method is suitable for practical engineering. Moreover, the behavior of the freezing arch reinforcement structure was analyzed combined with an engineering case.

关键词： shield machine launching freezing reinforcement arch structure internal force

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