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Development of simple sequence repeats (SSR) markers of ramie and comparison of SSR and inter-SSR marker systems

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Progress in Natural science:Materials International 2005年第02期15卷 42-47页

作者： ZHOU Jianlin1*, JIE Yucheng2., jiang Yanbo2. ZHONG Yingli1, LIU Yunhai1 and zhang Jian1**(1. {2. of Biochemistry and Molecular Biology, College of Life science, Hunan normal university, Changsha 410081, china.2. Institute of Bast Fiber Crops, Chinese Academy of Agricultural science, Changsha 410006, china. department of Biochemistry and Molecular Biology College of Life Science Hunan Normal University Changsha 410081 China. Institute of Bast Fiber Crops Chinese Academy of Agricultural Science Changsha 410006 China

Ramie (Boehmeria nivea L.) is an important bast fiber crop. To study genetic background of this species, we isolated and characterized microsatellite markers of ramie. A genomic library containing inserts of rapid amplification of polymorphic DNA (RAPD) fragments was constructed, and screened by PCR amplification using anchored simple sequence repeats as primers. A total of 2. clones were identified as positives, and 13 microsatellite loci were found after sequencing. The polymorphism of these 13 microsatellite loci was examined and the utility of simple sequence repeats (SSR) and inter-SSR (ISSR) marker systems for genetic characterization compared using 19 selected ramie cultivars. Both approaches successfully discriminated the 19 cultivars which differed in the amount of polymorphism detected. The level of polymorphism detected by SSR was 95.0%, higher than that by ISSR (72.3%), but the average polymorphism information content (PIC) of ISSR (0.651) was higher than that of SSR (0.441). The higher PIC value of ISSR suggests that ISSR is more efficient for fingerprinting ramie cultivars than SSR markers. However, because the SSR loci are codominant, they are more suitable for determining the homozygosity levels of ramie, constructing linkage map, quantitative trait loci study of complex traits and marker-assisted selection.

关键词： ramie (Boehmeria nivea L.Gaud) simple sequence repeats inter-simple sequence repeats

Reducing the voltage loss of Y-series acceptor based organic solar cells via ternary/quaternary strategies

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Chinese Chemical Letters 2024年第2期35卷 70-86页

作者： Pengyu zhang Zhiyang zhang Heng Sun Jie Li Yi Chen {2. Wang Chuanlang Zhan Key Laboratory of Advanced Materials Chemistry and Devices (AMC&DLab) of the department of Education of Inner Mongolia Autonomous Region Inner Mongolia Key Laboratory of Green CatalysisCollege of Chemistry and Environment ScienceInner Mongolia Normal UniversityHuhehot 010022China

In recent years, with the emergence of non-fullerene fused-ring acceptors, power conversion efficiencies (PCEs) of organic solar cells (OSCs) have exceeded 19%.However, compared to inorganic or perovskite photovoltaic cells, a higher voltage loss has become one of the key factors limiting further improvement in the PCEs of *** ternary/quaternary strategy has been identified as a feasible and effective way to obtain high-efficiency *** this review, a brief outline is given of the key roles that guest materials played in reducing voltage losses in solar cell devices and a brief look at the future material design and the design of ternary/quaternary systems.

关键词： Organic solar cell Ternary/quaternary strategy Open-circuit voltage Voltage loss Non-radiative recombination loss

Population genomic data reveal low genetic diversity,divergence and local adaptation among threatened Reeves's Pheasant(Syrmaticus reevesii)

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Avian Research 2024年第1期15卷 1-11页

作者： Qi Lu Pengcheng Wang jiang Chang De Chen Shenghan Gao Jacob Hoglund Zhengwang zhang Ministry of Education Key Laboratory for Biodiversity science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing100875China jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life SciencesNanjing Normal UniversityNanjing210023China State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing100012China State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of SciencesBeijing100101China department of Ecology and Genetics Animal EcologyUppsala UniversityUppsalaSweden

Population genomic data could provide valuable information for conservation efforts;however,limited studies have been conducted to investigate the genetic status of threatened ***’s Pheasant(Syrmaticus reevesii)is facing population decline,attributed to increases in habitat *** is a knowledge gap in understanding the genomic status and genetic basis underlying the local adaptation of this threatened ***,we used population genomic data to assess population structure,genetic diversity,inbreeding patterns,and genetic ***,we identified candidate genes linked with adaptation across the current distribution of Reeves’s *** present study assembled the first de novo genome sequence of Reeves’s Pheasant and annotated 19,458 *** also sequenced 30 individuals from three populations(Dabie Mountain,Shennongjia,Qinling Mountain)and found that there was clear population structure among those *** comparing with other threatened species,we found that Reeves’s Pheasants have low genetic *** of homozygosity suggest that the Shennongjia population has experienced serious *** demographic history results indicated that three populations experienced several declines during the glacial *** adaptative analysis among the populations identified 2.1 candidate genes under directional *** are involved in a large variety of processes,including the immune response and *** results suggest that the three populations should be considered as three different conservation *** current study provides genetic evidence for conserving the threatened Reeves’s Pheasant and provides genomic resources for global biodiversity management.

关键词： Conservation genetics Local adaptation Pheasant Whole-genome sequencing

Diagnostics in Linear Regression Model

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systems science and systems Engineering 1997年第1期7卷 37-44页

作者： jiang Jiancheng department of Probability & Statistics, Beijing {2., Beijing, 100871, china.zhang Xibin school of management, Tianjin {2., Tianjin, 300072. china.WU XizhiThis paper is supported by National Natural science Found

In this paper, we consider the interaction between cases from the view of influence analysis in linear regression model. Our new diagnostic statistics can reveal the masking phenomenen in the situation of multiple outliers,and the method can also be adapted to the influential analysis in a general model based on single case deletion diagnostic and local influence approach,therefore has a wide range of application.

关键词： global influence interaction local influence masking.

AN ADAPTIVE TRUST REGION METHOD FOR EQUALITY CONSTRAINED OPTIMIZATION

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Journal of systems science & Complexity 2003年第4期16卷 494-505页

作者： zhangJuliang zhangXiangstm ZHUOXinjian departmentofmanagement{2.andEngineering SchoolofEconomicsandManagementTsinghuaUniversityBeijin9100084China InstituteofAppliedMathematics AcademyofMathematicsandSystemsSciencesChineseAcademyofSciencesBeijing100080China schoolofInformationEngineering BeijingUniversityofPostsandTelecommunicationsBeijing100876China

In this paper, a trust region method for equality constrained optimizationbased on nondifferentiable exact penalty is proposed. In this algorithm, the trail step ischaracterized by computation of its normal component being separated from computation of itstangential component, i.e., only the tangential component of the trail step is constrained by trustradius while the normal component and trail step itself have no constraints. The other maincharacteristic of the algorithm is the decision of trust region radius. Here, the decision of trustregion radius uses the information of the gradient of objective function and reduced ***, Maratos effect will occur when we use the nondifferentiable exact penalty function as themerit function. In order to obtain the superlinear convergence of the algorithm, we use the twiceorder correction technique. Because of the speciality of the adaptive trust region method, we usetwice order correction when p = 0 (the definition is as in Section 2. and this is different from thetraditional trust region methods for equality constrained optimization. So the computation of thealgorithm in this paper is reduced. What is more, we can prove that the algorithm is globally andsuperlinearly convergent.

关键词： equality constrained optimization global convergence trust region method superlinear convergence nondifferentiable exact penalty function maratos effect

ROBUST NONPARAMETRIC REGRESSION BASED ON L_1-NORM AND B-SPLINES

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systems science and Mathematical sciences 1995年第2期8卷 187-192页

作者： SHI Peide(department of Probability and Statistics, Peking university, Beijing 100871,{2.zhang Zhengjun(school of management,Beijing university of Aeronautics and Astronautics,Beijing 100083, {2. 北京大学概率统计系北京北京航空航天大学管理学院北京

ＲＯＢＵＳＴＮＯＮＰＡＲＡＭＥＴＲＩＣＲＥＧＲＥＳＳＩＯＮＢＡＳＥＤＯＮＬ＿１－ＮＯＲＭＡＮＤＢ－ＳＰＬＩＮＥＳＳＨＩＰｅｉｄｅ（ＤｅｐａｒｔｍｅｎｔｏｆＰｒｏｂａｂｉｌｉｔｙａｎｄＳｔａｔｉｓｔｉｃｓ，Ｐｅｋｉｎｇ... 详细信息

ＲＯＢＵＳＴＮＯＮＰＡＲＡＭＥＴＲＩＣＲＥＧＲＥＳＳＩＯＮＢＡＳＥＤＯＮＬ＿１－ＮＯＲＭＡＮＤＢ－ＳＰＬＩＮＥＳＳＨＩＰｅｉｄｅ（ＤｅｐａｒｔｍｅｎｔｏｆＰｒｏｂａｂｉｌｉｔｙａｎｄＳｔａｔｉｓｔｉｃｓ，ＰｅｋｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎ...

关键词： B-spline function L1-norm estimator TURBO nonparametric regression

Community Detecting By Signaling on Complex Networks

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Community Detecting By Signaling on Complex Networks

Amelioration of habitat since the early Holocene contributed to the origin of agriculture in the farming-pastoral zone of northern china

第四届全国网络科学学术论坛暨研究生暑期学校

作者： Yanqing Hu Menghui Li Peng zhang Ying Fan Zengru Di~* department of {2. science,school of management Center for Complexity Research Beijing normal university,Beijing 100875,P.R.china

＜正＞Based on signaling process on copplex networks,a method for identifica- tion community structure is *** a network with n nodes,every node is coussmed to be a system which can send,receive,and recond *** node is taken as the initial signal source to inspire the whole network one time. Then the source node is endowed a n-dimensional vector which record the ef- fects of signaling *** this process,the topological relationship of nodes on the network could be transferred into the geometrical structure of vectors is n-dimensional Euclidian *** the best partition of groups is determined by F-statistics and the final community structure is given by K-means clus-tering method（KMC）.This method can detect community structure both in unweighted and weighted networks without any extra *** has been applied to ad hoc networks and some real networks such as Zachary Karate Club network and football team *** results indicate that the algo-rithm based on signaling process works well.

关键词： Complex network Community Structure Signaling Algorithm KMC

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science china.Earth sciences 2024年第8期67卷 2535-2546页

作者： Xin JIA Zhiping zhang Yonggang SUN Runqi jiang Shuangwen YI Wei CHEN Jue SUN Guoqiang LI Shuzhi WANG Enrui LI Xiaonong HU Qingchun BAO Harry F.LEE Huayu LU jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China Schlool of History and Culture Chifeng UniversityChifeng 024000China school of Geography and Ocean science Nanjing UniversityNanjing 210023China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and PalaeontologyChinese Academy of SciencesNanjing 210008China Key Laboratory of Western china.s Environmental systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Institute of Archaeology Chinese Academy of Social SciencesBeijing 100710China Ulanqab Museum Ulanqab 012000China The Institute of Cultural Relics and Archaeology Hohhot 010011China department of Geography and Resource management The Chinese University of Hong KongHong Kong 999077China Key Laboratory of Virtual Geographic Environment(Ministry of Education of PRC) Nanjing Normal UniversityNanjing 210023China school of Geography Nanjing Normal UniversityNanjing 210023China Institute of Environmental Archaeology Nanjing Normal UniversityNanjing 210023China

The origin of agriculture in the farming-pastoral zone of northern china.remains in *** central region of the Inner Mongolia Plateau is located in the core area of the farming-pastoral zone;thus,it is a critical region for exploring the origin of the dryland farming system in northern *** study selected the Yumin Site and Banan Site,which belong to the Yumin Culture-the beginning of Neolithic culture in Inner Mongolia-as the research *** on the quartz optically stimulated luminescence(OSL)dating on the sedimentary sections from the Yumin site(YM)and Banan site(BN1 and BN2.,the Holocene chronology framework of each section was *** that,by identifying carbonized grains in the Yumin site and the multi-proxy analysis of each section,we investigated the relationship between the origin of agriculture and climate change in this *** results revealed that the timing of the origin of agriculture recorded in the Yumin site lagged behind the timing of a significant increase of precipitation during the early Holocene but coincided with the timing of a significant increase of vegetation around 8.4 *** phenomenon was further confirmed by the published high-resolution paleoenvironmental records from the surrounding area of the Yumin *** propose that with the gradual amelioration of hydrothermal conditions since the beginning of the Holocene,the regional ecosystem had been improved,resulting in the gradual conversion of the land surface from infertile sand to organic-rich soil,providing an appropriate environmental foundation for the origin of dryland farming in northern china.around 8.4 *** study highlighted that the“accumulative environmental effects”during the early Holocene played a vital role in the origin of agriculture in northern china.and provided a reference for agricultural management in the context of future climate change.

关键词： Origin of agriculture Accumulative environmental effects Yumin Culture Northern china Holocene

ON SOLUTIONS TO SINGULAR FRACTIONAL DIFFERENTIAL systems WITH CONSTANT COEFFICIENTS

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Annals of Differential Equations 2010年第3期26卷 373-378页

作者： Xiaowen Zhao1, Wei jiang1, Hai zhang1,2.(1. {2. of Mathematical sciences, Anhui university, Hefei 2.0039 2. Dept. of Math., Anqing normal university, Anqing 2.6011, Anhui)

In this paper, we consider solutions to singular fractional differential systems with constant coefficients involving Riemann-Liouville differential operator. At first, we study the solvability of the systems. Then we... 详细信息

关键词： fractional differential systems solvability general solution