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Mitochondrial DNA diversity and origin of indigenous pigs in South China and their contribution to western modern pig breeds

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Journal of Integrative Agriculture 2019年第10期18卷 2338-2350页

作者： WANG Chen CHEN Yao-sheng HAN Jian-lin MO De-lin li xiu-jin liU Xiao-hong State Key Laboratory of Biocontrol School of Life SciencesSun Yat-sen UniversityGuangzhou 510006P.R.China CAAS-ILRI Joint Laboratory on livestock and Forage Genetic Resources Institute of Animal ScienceChinese Academy of Agricultural SciencesBeijing 100193P.R.China International livestock Research Institute (ILRI) Nairobi 00100Kenya

Indigenous pigs in South China are valuable genetic resources with many specific and unique characters, which have played an important role in the establishment of some western modern pig breeds. However, the origin and genetic diversity of indigenous pigs in South China have not been fully understood. In the present study, we sequenced 534 novel mitochondrial DNA (mtDNA) D-loop and assembled 54 complete mitogenome sequences for all 17 indigenous pig breeds from Fujian, Guangdong, Guangxi and Hainan in South China. These data were analyzed together with previously published homologous sequences relevant to this study. We found that all 13 coding genes of the mitogenomes were under purifying selection, but ND1 had the most variable sites and CYTB contained the most non-synonymous SNPs. Phylogenetic analysis showed that all indigenous pigs in South China were clustered into the D haplogroup with D1a1, D1b, D1c and D1e sub-haplogroups found to be dominant. Haplotype and nucleotide diversities of D-loop sequences ranged from 0.427 to 0.899 and from 0.00342 to 0.00695, respectively, among which all pigs in Guangdong had the lowest diversity. The estimates of pairwise FST, gene flow (Nm) and genetic distance (Da) indicated that most of these indigenous pig breeds differentiated from each other significantly (Plineal footprints from indigenous pigs in South China, especially the Spotted pigs distributed in Guangdong and Guangxi. The neutrality test (Fu’s FS) indicated that indigenous pigs from Fujian and Guangxi had gone through recent population expansion events (Plikely derived from the Mekong region and the middle and downstream regions of Yangtze River through Guangxi and Fujian. Our findings provide a complete and in-depth insight on the origin and distribution pattern of maternal genetic diversity of indigen

关键词： pig South China mitogenome D-loop genetic diversity

3D-QSAR Studies of Dimethoxyphenoxyphenoxy pyrimidines and Analogues

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Chinese Journal of Structural Chemistry 2000年第2期19卷 107-111页

作者： li Ai xiu WANG jin ling SU Hua Qing MIAO Fang Ming (Institute of Chemical Crystallography, Tianjin Normal University, Tianjin, 300074) 天津师范大学天津 3 0 0 0 74

Three dimensional quantitative structure activity relationships (3D QSAR) of a series of dimethoxyphenoxyphenoxypyrimidines and analogues which are known to be photosystem Ⅱ(PSⅡ)inhibitors have been studied using comparative molecular field analysis (CoMFA) method. The results suggest that the steric and electronic properties of substitutes at m position on the end phenyl ring have important influence on the Hill reaction inhibition.

关键词： D QSAR photosystem Ⅱinhibitor CoMFA

Incorporating genomic annotation into single-step genomic prediction with imputed whole-genome sequence data

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Journal of Integrative Agriculture 2022年第4期21卷 1126-1136页

作者： TENG jin-yan YE Shao-pan GAO Ning CHEN Zi-tao DIAO Shu-qi li xiu-jin YUAN Xiao-long ZHANG Hao li Jia-qi ZHANG Xi-quan ZHANG Zhe Guangdong Laboratory of lingnan Modern Agriculture/Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding College of Animal ScienceSouth China Agricultural UniversityGuangzhou 510642P.R.China State Key Laboratory of Biocontrol School of Life SciencesSun Yat-sen UniversityGuangzhou 510006P.R.China Guangdong Provincial Key Laboratory of Waterfowl Healthy Breeding College of Animal Sciences and TechnologyZhongkai University of Agriculture and EngineeringGuangzhou 510225P.R.China

Single-step genomic best linear unbiased prediction(ss GBLUP) is now intensively investigated and widely used in livestock breeding due to its beneficial feature of combining information from both genotyped and ungenotyped individuals in the single model. With the increasing accessibility of whole-genome sequence(WGS) data at the population level, more attention is being paid to the usage of WGS data in ss GBLUP. The predictive ability of ss GBLUP using WGS data might be improved by incorporating biological knowledge from public databases. Thus, we extended ss GBLUP, incorporated genomic annotation information into the model, and evaluated them using a yellow-feathered chicken population as the examples. The chicken population consisted of 1 338 birds with 23 traits, where imputed WGS data including 5 127 612 single nucleotide polymorphisms(SNPs) are available for 895 birds. Considering different combinations of annotation information and models, original ss GBLUP, haplotype-based ss GHBLUP, and four extended ss GBLUP incorporating genomic annotation models were evaluated. Based on the genomic annotation(GRCg6a) of chickens, 3 155 524 and 94 837 SNPs were mapped to genic and exonic regions, respectively. Extended ss GBLUP using genic/exonic SNPs outperformed other models with respect to predictive ability in 15 out of 23 traits, and their advantages ranged from 2.5 to 6.1% compared with original ss GBLUP. In addition, to further enhance the performance of genomic prediction with imputed WGS data, we investigated the genotyping strategies of reference population on ss GBLUP in the chicken population. Comparing two strategies of individual selection for genotyping in the reference population, the strategy of evenly selection by family(SBF) performed slightly better than random selection in most situations. Overall, we extended genomic prediction models that can comprehensively utilize WGS data and genomic annotation information in the framework of ss GBLUP, and valida

关键词： genomic selection prior information sequencing data genotype imputation haplotype

Intravitreal bevacizumab injection for chronic central serous chorioretinopathy

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Chinese Medical Journal 2010年第15期123卷 2145-2147页

作者： li xiu-juan ZHANG jin-song Department of Ophthalmology the First Affiliated Hospital of Zhengzhou University Zhengzhou Henan 450052 China

Central serous chorioretinopathy （CSC） is characterized by an idiopathic serous neurosensory detachment primarily affecting the *** most cases,the disorder is self-limited and spontaneously in 4 to 6 months, and the... 详细信息

关键词： central serous chorioretinopathy intravitreal bevacizumab retinal pigment epithelium detachment

Differentiating QoS and Un-conflicting Channel-times lot Allocation Algorithm in WDM

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Semiconductor Photonics and Technology 2005年第3期11卷 150-153,160页

作者： li li-xiu FENG jin-yuan YANG Qi-hong College of Phys. and Eng. South China University of TechnologyGuangzhou 510640 CHN

A new effective and reliabl e channel-timeslot allocation algorithm has been proposed, which is applied in WD M optical networks using fiber as their media to allocate the operational reques t. This new algorithm can differentiate the priority of all requests and avoid c onflict and collision in the process of distributing channel and timeslot for th e data waiting for transmission. The method in calculating the best wavelength c hannel and the best timeslot number is simply given. The algorithm is carried o ut in a math language. On the basis of the experiment results, the performance a nd feasibility of the algorithm are analyzed, which prove that the allocation me thod can reach the requirements of an algorithm both in space complexity and tim e complexity .

关键词： WDM Channel Timeslot Conflictr Collision Quality of service

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基于梯度的医学图像伪彩色编码

光学技术 2008年第4期34卷 576-578,582页

作者：李今秀李均利魏平宁波大学数字技术与应用软件研究所浙江宁波315211 浙江大学计算机科学与技术学院杭州310027

根据医学图像的特点和人的视觉特性,提出了一种基于梯度的非线性伪彩色编码新方法。利用梯度算子得到图像的梯度场,并确定阈值。根据梯度值与阈值的比较,大于阈值的是基于梯度值的编码方法,用红色编码;否则是基于灰度值的编码方法。通... 详细信息

根据医学图像的特点和人的视觉特性,提出了一种基于梯度的非线性伪彩色编码新方法。利用梯度算子得到图像的梯度场,并确定阈值。根据梯度值与阈值的比较,大于阈值的是基于梯度值的编码方法,用红色编码;否则是基于灰度值的编码方法。通过定义的两个阈值界定范围,设计非线性的正弦函数来进行伪彩色编码。由于映射函数中的三个参数k_1,k_2和k_3,所以增加了算法的灵活性。通过实验比较,处理后的医学图像轮廓更清晰,层次感更强,能有效地突出病灶区,有利于医生的诊断。

关键词：医学图像梯度伪彩色编码滤波

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从漠北到河东:萨珊银币与草原丝绸之路

青海民族研究 2018年第1期29卷 106-111页

作者：李锦绣中国社会科学院北京100000

本文以唐河东九姓纳"羊钱"为中心,结合蒙古国新发现的萨珊银币,对草原丝绸之路上萨珊银币贸易圈问题进行补充研究。指出河东九姓内附后税银、羊,是对漠北税制、币制的延续。随着九姓的迁徒,他们将漠北的货币形态带入太原以北,这不但使... 详细信息

本文以唐河东九姓纳"羊钱"为中心,结合蒙古国新发现的萨珊银币,对草原丝绸之路上萨珊银币贸易圈问题进行补充研究。指出河东九姓内附后税银、羊,是对漠北税制、币制的延续。随着九姓的迁徒,他们将漠北的货币形态带入太原以北,这不但使草原丝绸之路向更广阔范围内发展,而且也将萨珊银币的行用范围扩展到唐农耕区的边缘,逐步进入唐朝腹地。草原银币贸易圈的出现与扩展,体现了游牧民族对东西文化交流的重大贡献。

关键词：唐九姓羊钱萨珊银币草原丝绸之路

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古代“丝瓷之路”综论

新疆师范大学学报（哲学社会科学版） 2017年第4期38卷 53-60页

作者：李锦绣中国社会科学院历史研究所北京100732

"丝瓷之路"是自古以来连接东西方海陆两路交通的要道,涵盖陆上丝绸之路和海上丝绸之路。文本对"丝瓷之路"的研究内容、发展阶段以及陆海丝绸之路的差异与联系进行了综合论说,指出"丝瓷之路"是东西方文明通过海陆两路进行交通、交流、互... 详细信息

"丝瓷之路"是自古以来连接东西方海陆两路交通的要道,涵盖陆上丝绸之路和海上丝绸之路。文本对"丝瓷之路"的研究内容、发展阶段以及陆海丝绸之路的差异与联系进行了综合论说,指出"丝瓷之路"是东西方文明通过海陆两路进行交通、交流、互动与融合的道路,涉及经济、政治、军事、文化、民族、社会、地理与自然科学等诸多方面,而不仅仅是商品流通之路。"丝瓷之路"概念的提出,其本身就有强调"丝路"和"瓷路"关系研究的作用,以往研究者将两者孤立起来进行研究的状况应有所改变。

关键词：丝瓷之路陆海丝绸之路东西方文化交流西域中国南海

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网络时代的终身教育与图书馆建设

图书馆论坛 2005年第3期25卷 222-224,122页

作者：李金秀中共广东省委党校图书馆广东广州510053

着眼学习型社会的含义与特征,分析网络时代图书馆的职能变化及其在终身教育中的重要地位,探讨网络时代加强图书馆建设的若干措施。

关键词：图书馆建设网络时代终身教育学习型社会重要地位职能变化