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Genetic diversity and population structure of 288 potato(Solanum tuberosum L.) germplasms revealed by SSR and AFLP markers

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Journal of Integrative Agriculture 2017年第11期16卷 2434-2443页

作者： wang Jian HOU Lu wang ruo-yu HE Miao-miao LIU Qing-chang Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis and Utilization Ministry of EducationChina Agricultural University Institute of Biotechnology Qinghai Academy of Agriculture and Forestry Science Scientific Observing and Experimental Station of Crop Pest in Xining Ministry of Agriculture/Key Laboratory of Agricultural Integrated Pest ManagementQinghai Academy of Agriculture and Forestry Science Department of Statistics University of Connecticut

Potato （Solanum tuberosum L.） is an important staple food and economic crop in many countries. China has led world potato production in recent years. To understand the genetic diversity of potato germplasms and to enrich the current gene pool for potato improvement, we made a global collection consisted of 288 potato germplasms from eight countries and the International Potato Center （CIP）. Using SSR and AFLP techniques, we evaluated the genetic diversity and population structure of these 288 potato accessions. A total of 190 alleles on 20 SSR loci were detected and all of the SSR alleles were polymorphic among these potato germplasms with an average of 9.5 alleles per SSR locus ranging from 2 to 23. The effective number of alleles per locus （Ne＊）, Nei＇s genetic diversity （H＊）, and Shannon＇s information index （I＊） was from （0.1709＋0.3698） to （1.6166＋0.3414）, （0.076＋0.1388） to （0.3812＋0.1886）, and （0.1324＋0.1970） to （0.5347＋0.1440）, respec- tively, and the mean polymorphic information content （PIC） value was 0.7312. A total of 988 AFLP alleles were detected by 10 AFLP primer combinations with 983 polymorphic alleles, and 99.49% alleles was polymorphic with an average of 98.3 polymorphic alleles per primer combination ranging from 91 to 116. The values of Ne＊, H＊ and/＊ were from （1.5162＋0.311 ） to （1.6423＋0.3278）, （0.3114＋0.145） to （0.3675＋0.1121）, and （0.4761＋0.1792） to （0.547＋0.1322）, respectively, and the average PIC value was 0.9871. Bayesian analysis discriminated the accessions into seven subgroup and an admix group. The majority of accessions from CIP and China were assigned into SG1, SG5, SG6, SG7 and admix group. Accessions in SG3 were mainly from CIP and two small groups SG2 and SG4 were mainly from northeastern China. In general, the results obtained from Bayesian statistical analysis, cluster analysis and principal coordinate analysis consistently revealed the lack of geographical differentiation among country-wide collections, indicating germplasm introdu

关键词： potato germplasms genetic diversity population structure SSR AFLP

基于Bootstrapping的因特网流量分类方法

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北京邮电大学学报 2014年第5期37卷 66-70,79页

作者：刘珍王若愚刘琼华南理工大学软件学院广州510006 华南理工大学计算机科学与工程学院广州510006

针对因特网流量分类面临的流量类别标记瓶颈和类别样本数分布不平衡,提出基于Bootstrapping的流量分类方法,使用少量有标记样本训练初始分类器,迭代利用无标记样本扩展样本集并更新分类器.在构建扩展样本集过程中,将无标记样本在某后验... 详细信息

针对因特网流量分类面临的流量类别标记瓶颈和类别样本数分布不平衡,提出基于Bootstrapping的流量分类方法,使用少量有标记样本训练初始分类器,迭代利用无标记样本扩展样本集并更新分类器.在构建扩展样本集过程中,将无标记样本在某后验概率分布下的正确分类行为视为一个概率事件,建立新的置信度计算方法,以减少扩展样本集中的噪声样本;基于概率近似正确学习理论建立启发式规则,注重选择小类样本加入扩展样本集,缓解类别样本数分布的不平衡.实验结果表明,与初始分类器相比,基于Bootstrapping的流量分类器总体分类准确率可提高9.46%;与现有半监督学习方法相比,小类分类准确率提高2.22%.

关键词：半监督学习类别不平衡 Bootstrapping Internet流量分类

Treatment of portal hypertension from portal vein cavernoma with the meso-Rex bypass

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Chinese Medical Journal 2013年第5期126卷 971-973页

作者： LI Jin-liang CHEN Wei-xiu XU Chang-xian wang ruo-yi CHEN yu-li Division of Pediatric Surgery Department of Surgery SecondHospital and Medical School of Shandong University JinanShandong 250033 China

Extrahepatic or prehepatic portal vein cavernoma and thrombosis is a more common condition in children than that in adult patients with extrahepatic or prehepatic portal vein obstruction （EHPVO）, which involves approximately 30% of children with portal hypertension and can involve all the portal hypertension complications. Cavernomatous transformation of the portal vein is common after portal thrombosis in non-cirrhotic patients. This challenging situation is relatively more frequent after liver transplantation, particularly in pediatric recipients. Acute bleeding from esophageal and gastric varices is temporarily treated by sclerotherapy or variceal banding. Children who experience continued bleeding despite medical management or who experience clinically significant hypersplenism are referred for surgery.

关键词： hypertension portal extrahepatic bypass surgery

“一带一路”背景下中国与哈萨克斯坦深化旅游合作面临的挑战与路径分析

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新疆大学学报（哲学社会科学版） 2023年第6期51卷 40-49页

作者：王若雨新疆财经大学经济学院新疆乌鲁木齐830012

哈萨克斯坦长期与中国保持着睦邻友好和经贸合作关系,是“丝绸之路经济带”的必经之地,具有重要的地缘政治地位。我国与哈萨克斯坦开展跨区域旅游合作具有丰富的自然资源与人文历史基础。“一带一路”倡议提出后,两国旅游领域合作成效... 详细信息

哈萨克斯坦长期与中国保持着睦邻友好和经贸合作关系,是“丝绸之路经济带”的必经之地,具有重要的地缘政治地位。我国与哈萨克斯坦开展跨区域旅游合作具有丰富的自然资源与人文历史基础。“一带一路”倡议提出后,两国旅游领域合作成效显著、成果丰硕。近年来受到疫情等外部因素影响,两国区域旅游合作进程放缓。随着后疫情时代的到来,全球旅游业复苏、多边合作机制的建立以及哈国对旅游业的投入增大为中国与哈萨克斯坦深化旅游合作创造了良好前景。分析发现,两国可以通过新媒体宣传、打造精品旅游节点城市、开展基础设施建设合作、建立跨区域旅游数字平台等多种合作模式来深化区域旅游合作,推动区域旅游经济增长。

关键词： “一带一路”倡议哈萨克斯坦旅游合作

工艺参数对镀铝锌钢板点焊接头质量与组织的研究

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电焊机 2011年第5期41卷 66-71页

作者：王若愚四川机电职业技术学院四川攀枝花617000

通过镀铝锌钢板点焊实验,对十二组不同工艺参数下获得的点焊接头进行抗剪力实验和金相分析,研究表明:当采用较小的焊接电流和较短的焊接时间,接头熔合不良;焊接电流太大,焊接过程中飞溅很大,焊点表面压痕深度超标,同时形成方向性很强的... 详细信息

通过镀铝锌钢板点焊实验,对十二组不同工艺参数下获得的点焊接头进行抗剪力实验和金相分析,研究表明:当采用较小的焊接电流和较短的焊接时间,接头熔合不良;焊接电流太大,焊接过程中飞溅很大,焊点表面压痕深度超标,同时形成方向性很强的粗大柱状晶;适当增加电极压力,可使柱状晶发生倾斜,方向性减弱。研究确定了0.8 mm厚镀铝锌钢板较佳的工艺参数为I=8.5～9.0 kA,T=14 cyc,FW=2 400 N,用这组工艺参数焊接,点焊接头抗剪力、熔核直径均超过了《点焊焊接区的检验方法》标准中规定的A级要求,熔透率、焊点表面压痕深度均能满足质量要求。

关键词：镀铝锌钢板点焊宏观金相显微组织

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模式选择阀开度对变循环压缩系统匹配的影响

工程热物理学报 2020年第3期41卷 562-572页

作者：刘宝杰王若玉于贤君北京航空航天大学能源与动力工程学院北京100191 北京航空航天大学航空发动机气动热力国防重点实验室北京100191 先进航空发动机协同创新中心北京100191

对双外涵变循环压缩系统进行了建模和全三维数值模拟,分析了模式转换过程中第二外涵道倒流对系统气动性能及部件匹配规律的影响。随着倒流流量的增大,变循环压缩系统的第一外涵道比和总涵道比提高,风扇总压比升高,CDFS与高压压气机的总... 详细信息

对双外涵变循环压缩系统进行了建模和全三维数值模拟,分析了模式转换过程中第二外涵道倒流对系统气动性能及部件匹配规律的影响。随着倒流流量的增大,变循环压缩系统的第一外涵道比和总涵道比提高,风扇总压比升高,CDFS与高压压气机的总压比降低。倒流主要影响风扇后面级的气动性能。倒流导致CDFS进口流场发生畸变,CDFS下游第一分流环局部流场严重恶化,应及时调节系统控制参数防止压缩系统失效。

关键词：变循环发动机压缩系统倒流匹配

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人机合作中延展的归责方式何以可能?

科学技术哲学研究 2024年第5期41卷 30-36页

作者：郭菁王若宇大连理工大学人文学院辽宁大连116024

人机合作是一种混合行动模式,其行动的后果不是由单个个体所导致,而是在人与机器的动态交互关系中产生。当损害发生时,倘若没有“谁”能够为交互行动所产生的后果负责,就会出现无人负责的责任困境。传统的个体主义路径由于采用分离的、... 详细信息

人机合作是一种混合行动模式,其行动的后果不是由单个个体所导致,而是在人与机器的动态交互关系中产生。当损害发生时,倘若没有“谁”能够为交互行动所产生的后果负责,就会出现无人负责的责任困境。传统的个体主义路径由于采用分离的、立足于个人意向的以及静态封闭的归责形式,忽略了人机合作中混合的整体关系,不能有效地解决这一困境。这便需要以一种延展-耦合论的整体视角,依照延展的归责方式,把责任归于耦合的、立足于共同意向的以及动态开放的人机延展行动体,由此来回应责任归属难题。

关键词：人机合作责任归属个体主义人机延展行动体延展责任

Silk damping in scalar-induced gravitational waves: a novel probe for new physics

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 79-85页

作者： Yan-Heng yu Sai wang Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences School of Physics University of Chinese Academy of Sciences

Silk damping is well known in the study of cosmic microwave background（CMB） and accounts for suppression of the angular power spectrum of CMB on large angular multipoles. In this article, we study the effect of Silk damping on the scalar-induced gravitational waves（SIGWs）. Resulting from the dissipation of cosmic fluid, the Silk damping notably suppresses the energydensity spectrum of SIGWs on scales comparable to a diffusion scale at the decoupling time of weakly-interacting particles. The effect offers a novel observable for probing the underlying particle interaction, especially for those mediated by heavy gauge bosons beyond the standard model of particles. We anticipate that pulsar timing arrays are sensitive to gauge bosons with mass ～10～3-10～4 GeV, while space-and ground-based interferometers to those with mass ～10～7-1012GeV, leading to essential complements to on-going and future experiments of high-energy physics.

关键词： scalar-induced gravitational waves Silk damping new physics

Constructing 2D bismuth-based heterostructure for highly efficient photocatalytic CO2 reduction

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Tungsten 2025年第1期7卷 71-79页

作者： ruo-Hang Xu Hao-yu Jiang Dan-Dan Cui Kun-Rong Du Hong-Run Zhang Sheng-Jie Xu Ya-Qi Li Zhi-Zhen Ren Liang wang Wei-Chang Hao Yi Du School of Physics and BUAA-UOW Joint Research Centre Beihang University Shenzhen Institute of Beihang University Centre for Catalysis and Clean Energy School of Environment and Science Griffith University

Reforming carbon dioxide（CO2） into fuels and valuable chemicals using solar energy holds significant potential for emission reduction and addressing energy supply *** recombination of photocarriers remains a major obstacle,however,to enhancing solar energy conversion efficiency in the photocatalytic reaction *** two-dimensional materials,constructing heterogeneous structures has emerged as an effective strategy to enhance the separation of photoexcited carriers by leveraging the internal electric field at the heterogeneous ***,we present a facile strategy for preparing Bi4NbO8Br/Bi2WO6plate-on-plate Z-scheme junctions with a strong internal electric field by in situ *** unique heterostructure facilitates efficient separation and transport of photoexcited charges by harnessing the internal electric field induced by chemical bonding at the lateral ***,the Bi4NbO8Br/Bi2WO6heterostructure exhibits enhanced CO2photoreduction properties,along with a CO yield rate of approximately 35 μmol·g-1·h-1under full light *** work offers novel insights into the synthesis of unique hetero structures intended to enhance the efficiency of photocatalytic CO2reduction.

关键词： Bi4NbO8Br/Bi2WO6 CO2 reduction Heterostructures Photocatalysts