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Genetic diversity center of cultivated soybean(Glycine max) in China——New insight and evidence for the diversity center of Chinese cultivated soybean

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Journal of Integrative Agriculture 2016年第11期15卷 2481-2487页

作者： WANG Li-xia LIN Fan-yun LI Lin-hai LI Wei YAN Zhe LUAN Wei-jiang PIAO Ri-hua GUAN Yuan NING Xue-cheng ZHU Li MA Yan-song DONG Zhi-min ZHANG Hai-yan ZHANG Yue-qiang GUAN Rong-xia LI Ying-hui LIU Zhang-xiong CHANG Ru-zhen QIU Li-juan The national Key Facility for Crop Gene resources and Genetic Improvement (NFCRI)/Key Laboratory of Germplamsm {2. Ministry of Agiculture/Institute of Crop SciencesChinese Academy of Agricultural Sciences College of Agriculture Northwest A & F University College of Agriculture Northeast Agricultural University College of Science and Technology Xinjiang Agricultural University Department of Agronomy Jilin Agricultural University Department of Agronomy Liaoning Agricultural University

Information on the center of genetic diversity of soybean（Glycine max） will be helpful not only for designing efficient strategies for breeding programs, but also for understanding the domestication and origin of this species. Here, we describe an analysis of genetic diversity based on simple-sequence repeat（SSR） variations within a core collection of 2.111 accessions of Chinese soybean landraces. Prior to the diversity assessment, the geographic origin of each accession was mapped. The map was then divided into grids each 2.5° in latitude and 5° in longitude. We found two regions that had higher number of alleles（NA） and greater polymorphic information content（PIC） values than the others. These regions are adjacently located within grid position of {2.°–{2.°N×105°–110°E, which includes the valley of the middle and lower reaches of the Wei River, and the valley of the upper reaches of the Hanjiang River. It was also observed that in many regions, genetic diversity decreased with the increase in distance from the center. Another region, in northern Hebei Province（115°–12.°E×40°–42.5°N）, was observed having higher diversity than any surrounding regions, indicating that this is a sub-center of soybean diversity. Based on the presented results, the domestication and origin of soybean are also discussed.

关键词： Glycine max genetic resources SSRs diversity center domestication

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QoS路由近似算法的研究

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计算机科学 2003年第1期30卷 105-107,96页

作者：张信明陈国良黄刘生徐云中国科技大学计算机科学技术系国家高性能计算中心合肥230027

In general,finding a feasible route subject to multiple additive QoS constraints is an NP-complete *** this paper,we first analyze the constraints and their properties that can reflect the basic characteristics of a networkand support the fundamental QoS requirements. Then,we show that the unicast QoS routing problem can be general-ized as a Multiple Constrained Path(MCP) or Restricted Shortest Path(RSP) problem. Finally,We investigate the ef-ficient approximate algorithms for MCP and RSP,and how to convert a RSP problem to an easier MCP problem.

关键词： QoS 路由近似算法服务质量网络资源计算机网络

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Stoichiometry on Biosynthesis of Anabaena Cells for Analysis of Metabolism and Growth

Stoichiometry on Biosynthesis of Anabaena Cells for Analysis...

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Third Joint China/USA Chemical Engineering Conference

作者： Guoce Yu Zhaoling Cai Dingji Shi & Fan Ouyang State Key Laboratory of Biochemical Engineering Institute of Chemical Metallurgy Chinese Academy of Sciences Beijing 100080 P. R. China research center of Photosynthesis Institute of Botany Chinese Academy of Sciences Beijing 10009{2.P. R. China

＜正＞Rich in many kinds of nutritional ingredients, the nitrogen-fixing cyanobacteria Anabaena sps. have been adopted as basic materials in genetic engineering of microalgae, and cultures of Anabaena cells are thus of greater significance due to the fact that some valuable protein products can be produced safely and effectively by cultures of transgenic microalgae. Anabaena are one typical genus of filamentous cyanobacteria whose morphology and physiology have been studied extensively. Making an intrinsic insight into ceil growth stoichiometry is accordingly possible and can be conducive to more efficient cultures of Anabaena cells. In this work the contents and compositions of macromolecules in an Anabaena sp. cell were drawn from numerous literature mainly on the basis of the data of Anabaena cylindrica. The requirements of monomeric building blocks （amino acids, nucleotides, monosaccharides, fatty acids, etc.） for each kind of macromolecules were thus calculated. Finally, in terms of different requirements of precursor metabolites for building block synthesis, the amounts of 12.kinds of precursor metabolites required in making per unit dry weight of Anabaena sp. ceils were derived, i.e., 598.7 glucose-6-phosphate + 506.6 fructose-6-phosphate + 406.6 pentose-5-phosphate + 43..0 erythrose-4-phosphate + 3..0 triose phosphate + 668.7 3.phosphoglycerate + 102..9 phosphoenolpyruvate + 2.59.5 pyruvate + 1497.1 acetyl CoA + 13.0.6 oc-ketoglutarate + 1914.9 oxalacetate （μmol） →lg cells （The requirement of succinyl CoA is trivial.）. This stoichiometric relation on biomass synthesis is helpful in understanding and analyzing metabolism and growth of Anabaena sps. cells, e.g., in metabolic flux analysis during cultures of Anabaena cells.

关键词： stoichiometry biosynthesis Anabaena sps. macromolecuie building block precursor metabolite

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The Relationship Among Photoinhibition, Photooxidation and Early Aging at a Late Development Stage in Different Varieties with High Yield

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Agricultural Sciences in China 2002年第6期1卷 618-625页

作者： JIAO De-mao, LI Xia, HUANG Xue-qing and JI Ben-hua( Institute of Agrobiological Genetics and Physiology, Jiangsu Academy of Agricultural Sciences , nanjing 2.0014 , P.R. China Department of Biology, Nantong Normal College, Nantong 2.6007 , P.R. China) Institute of Agrobiological Genetics and Physiology Jiangsu Academy of Agricultural Sciences Nanjing 210014 P. R . China Department of Biology Nantong Normal College Nantong 226007 P. R . China

Using six high yield varieties from different ecological districts in China the parameters of Chl fluorescence, the performance of membrane lipid peroxidation and the reduction of Chl content in flag leaf under natural condition at the later developmental stages (from heading stage to mature stage). The results showed that Fv/Fm , decreased gradually, the excessive light energy led to the accumulation of active oxygen O2., H2.2.and the product of membrane-lipid peroxidation, MDA, which resulted in the reduction of Chl content and early aging due to photooxidation during the course of senescence of flag leaf. This phenomenon varied obviously in rice varieties. When comparina japonica tolerant to photooxidation, Fv/Fm in indica shanyou 63.susceptible to photoxidation decreased significantly. An increase of active oxygen and a sharp drop of Chl content, resulted in 'yellowish' early aging and influenced filling and setting of rice grain. The mechanism on early aging in indica was related to light and temperature conditions in filling stages. On a fine day (above 2.1), PS Ⅱ reaction center exhibited a dynamic change on revisable inactivation. Under strong midday light, PS Ⅱ function in indica exhibited obvious down-regulation and photoinhibition; Under strong light with low temperature, PS Ⅱ resulted in photodamage, showing early aging, which were related to the degradation of PSⅡ - D1 Protein and the inhibition of the endogenous protecting system such as Xanthophyll cycle and the enzymes of scavenging active oxygen. The results suggested that for a view of high-yield breeding, on the basis of a good type-plant, giving consideration to the {2. of heterosis and resistance to early aging, selecting japonica or a sterile line with japonice genotype as maternal was a breeding strategy worthy of being paid more attention.

关键词： Rice Characteristics of chl fluorescence Photoinhibition Photooxidation Early aging

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添加铁基生物炭对Cd在土壤-水稻体系中迁移转化的效应及其机制

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生态环境学报 2020年第8期29卷 1662-1668页

作者：曾晓舵刘传平孙岩李芳柏吴启堂王向琴广东省科学院/广东省生态环境技术研究所/华南土壤污染控制与修复国家地方联合工程研究中心/广东省农业环境综合治理重点实验室华南农业大学资源环境学院

该研究将探讨铁基生物炭对Cd在土壤-水稻系统中迁移转化的影响及Fe和Cd之间的相互作用关系,为研发成本低廉、实用、高效和安全的Cd污染土壤修复技术提供科学支持。采集广东省韶关市韶关电厂周边受Cd污染的水稻土,设置水稻盆栽试验,每盆... 详细信息

该研究将探讨铁基生物炭对Cd在土壤-水稻系统中迁移转化的影响及Fe和Cd之间的相互作用关系,为研发成本低廉、实用、高效和安全的Cd污染土壤修复技术提供科学支持。采集广东省韶关市韶关电厂周边受Cd污染的水稻土,设置水稻盆栽试验,每盆装土10kg,处理如下:（1）对照,（2.添加纯的生物炭100g,（3.添加ω（Fe）=0.5%的铁基生物炭100 g,（4）添加ω（Fe）=1%的铁基生物炭100 g,（5）添加ω（Fe）=2.5%的铁基生物炭100 g,（6）添加ω（Fe）=5%的铁基生物炭100 g,（7）添加Fe粉5 g。分析各处理对水稻成熟期根表铁膜Fe和Cd、水稻各部位Cd含量的影响,并探讨此影响的机制。结果表明,（1）铁基生物炭的添加显著降低了水稻根部对Cd的吸收。在7个不同处理中,水稻各部位总Cd含量大小为根表铁膜、根系>稻杆>稻壳>稻米,呈现出植株从下往上依次递减的趋势。根表铁膜所固定的Fe和Cd之间存在显著的正相关关系。（2.铁基生物碳的添加能在一定程度上改变Cd在土壤中的赋存形态。根际土壤中以铁锰氧化物结合的Cd含量随着铁基生物碳含铁量的增加而有所增加,而离子交换态的Cd和碳酸盐结合态的Cd含量相应有所下降,进入水稻体系的Cd含量也相应降低。（3.土壤中无定型铁氧化物是土壤中Cd的重要的汇,强烈影响着Cd在土壤-水稻体系中的迁移。其Cd含量与稻米、稻壳、茎叶和根系中的Cd含量之间存在着显著的负相关关系,铁基生物碳的添加能有效地增加土壤中无定型铁氧化物的含量,从而对生物可利用性的Cd进行有效吸附,降低其对水稻的危害,降低Cd在稻米中的累积。这表明铁基生物炭是良好的土壤Cd钝化剂和土壤改良剂,可在大田中应用。

关键词：铁基生物炭土壤水稻镉迁移转化吸收

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Solution of the Bottleneck Problems in Polyploid Rice Breeding

Solution of the Bottleneck Problems in Polyploid Rice Breedi...

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湖北省遗传学会、江西省遗传学会2.06年学术年会暨学术讨论会

作者： Detian Cai //, Jianguo Chen, Dongling Chen, Zhaojian Song, Wei Zhang, Chunhua Yang, Aiyun Wang, Youqi Liu, Chaoqun Du, Qin Peng, Yaping Hu, Lixia Zhang, Jianxin Liu, Zifan Yang, Guangcun He, Yunchun Song, Lijia Li, Longping Yuan, Xinggui Lu College of Life Sciences, Hubei University, Wuhan, 43.062. China College of Life Sciences, Wuhan University, Wuhan, 43.072. China {2. Hybrid Rice research and Development {2. in China, Changsha, 41012., China Hubei Agricultural Academy, Wuhan, 43.070, China

To solve the potential crises of food shortage, strategies for the breeding of super rice have been suggested. They based on the rationale of intervarieties cross and diploidy. The best hybrid rice combination just increased yield 15% more than control varieties and did not reach the demand of resolving the crises of food shortage. However, the duplication increases of yield in wheat, cotton, rape-seed and other crops during their evolution from diploid to polyploid gives us inspiration. A new strategy used double heterosis of wide cross and polyploidization to breed super rice was developed by us. Its principle is different from conventional cross and hybrid rice breeding. Three key techniques including utilization of the parent with relative distance, wide compatibility and Ph (pairing homoeologous) genes were applied. Here we showed the results from using the strategy to break through two bottlenecks in polyploid rice breeding. A technique program of inducing polyploid rice in high frequency (46.7%) was established (Fig 1), and two lines of polyploid meiosis stability (PMeS) gene with high rate of seed set alike Ph functioned in wheat were selected (Fig 2.3.. More than 150 combinations of polyploid intersubspecific rice with powerful heterosis have been developed. The demonstration culture also showed the more advantage than diploid (Fig 4). The fact has proved that the bottleneck problems have been dissolved. Polyploid rice breeding can be used in super rice breeding.

关键词： Ployploid rice Wide cross Heterosis Meiosis PMeS

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A TRAFFIC OVERSTOCK RESLOVE SCHEME IN WLAN

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Journal of Electronics(China) 2005年第5期22卷 478-484页

作者： Liu Jing Li Jiandong Chen Yanhui Information Science Institute National Key Lab of ISN Xidian University Xi＇an 710071 China

A new Multiple Access Control (MAC) protocol-User Adaptive Scheduling Multiple Access (UASMA) protocol is proposed in this paper. It can well schedule the packet transmission according to the exact number of active Mobile Terminals (MTs) determined by selforganizing algorithm and adjust the number of packets sent by one node in one frame *** protocol employs a special frame structure, which makes it possible to allocate channel resource to uplink and downlink traffic according to their respective service requirements. The proposed concept of referenced-frame-length can ensure the frame length varies in a certain range,and consequently increase the utilization efficiency of the channel greatly. Meanwhile, UASMA protocol uses an efficient collision resolution algorithm to guarantee that active MTs can access the channel rapidly. Finally, the performance of UASMA protocol is evaluated by simulation and it is also compared with carrier sense multiple access, rounding-poll and UPMA protocols. The results show that the UASMA has better performance than others.

关键词： Multiple Access Control (MAC) protocol Round-robin User number Packet overstock

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An efficient Algorithm for Indoor Positioning in WLAN Environments using KNN Algorithm and Pass-Loss Model

An Efficient Algorithm for Indoor Positioning in WLAN Enviro...

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2.11年全国通信安全学术会议

作者： Liangzi Ding,Kangfeng Zheng Information Security center,Beijing University of Posts and Telecommunications Beijing 100876,China

＜正＞A new approach has been presented to increase the location estimation accuracy in WLAN *** Location fingerprint method base on KNN algorithm,optimal parameter has not been theoretically *** studies have shown that value of k in KNN algorithm have a great impact on the positioning accuracy and should comprehensively consider the cumulative probability,the average location error distance,the complexity of the algorithm and some other *** novel technology we propose provides a practical method to select the value of k *** first uses triangulation location method based on Pass - Loss model to calculate the area where the typical measured point may exist,and then uses the traditional KNN algorithm to select k closest vectors from the regional location fingerprint database which are in the triangulation location intersection district,finally calculate their estimated *** experimental results show that the new method improves the original KNN algorithm and can achieve a great positioning accuracy.

关键词： location fingerprint KNN algorithm Pass - Loss Triangulation location

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二氧化碳捕集、利用与封存环境风险问卷调查研究

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环境工程 2018年第2期36卷 6-9,26页

作者：曹丽斌赵学涛蔡博峰谷莹莹周颖李琦马劲风胡丽莎王永胜赵兴雷王保登环境保护部环境规划院气候变化与环境政策研究中心北京100012 北京交通大学北京100044 中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室武汉430070 西北大学地质学系二氧化碳捕集与封存技术国家地方联合工程研究中心西安710069 中国地质调查局水文地质环境地质调查中心河北保定071051 神华鄂尔多斯煤制油分公司内蒙古鄂尔多斯017209 北京低碳清洁能源研究所工艺工程研发中心北京102209

基于对从事应对气候变化的政府管理人员、科研人员和相关企业人员开展问卷调查,分析他们对CCUS技术和相关项目的环境安全性认知程度,为完善《二氧化碳捕集、利用与封存环境风险评估技术指南(试行)》(以下简称《指南》)提供重要依据。结... 详细信息

基于对从事应对气候变化的政府管理人员、科研人员和相关企业人员开展问卷调查,分析他们对CCUS技术和相关项目的环境安全性认知程度,为完善《二氧化碳捕集、利用与封存环境风险评估技术指南(试行)》(以下简称《指南》)提供重要依据。结果显示,大部分被调查对象对CCUS技术有所了解,但是对于CCUS项目的环境安全性认识还比较模糊,未来《指南》的评估范围应侧重于采用最大可信事故计算CO_2.大气、地表水、地下水等扩散来定义或者根据CO_2.移分布来定量评估。CCUS技术各环节对环境风险影响大小进行排序,捕集环节应该重点考虑捕集工艺和环境风险物质,运输环节重点考虑运输设备材质、运输方式和运输规模,利用和封存环节建议4项因素均需充分考虑。

关键词：二氧化碳利用与封存关注度环境风险技术指南

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The research of Multimedia Data Transmission Basis on the Inventory and Queuing Theory

The Research of Multimedia Data Transmission Basis on the In...

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2.12.national Conference on Information Technology and Computer Science

作者： Shen Jia-jie Computer center of School of Information Science & Technology East china normal university Shanghai,china

Aim to problem how the packet size effect to the multimedia data transmission and how to design the packet size to reach the best efficient of *** research is mainly to use the inventory and queuing theory find the best way to design the send packet *** the model is established and calculated,The best value have been *** experiment result also proof that exist best point of the packet size.

关键词： Multimedia transmission inventory theory Queuing theory network efficiency

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