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The portrait of.a lady

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On the Evolution of.Consanguinities

作者： edited by Robert D. bamberg.

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Applied Mathematics 2017年第4期8卷 550-561页

作者： Paul G. bamberg Department of.Mathematics Harvard University Cambridge Massachusetts USA

“Consanguinity” is a gender-neutral term f.r “f.aternity” or “sorority.” Initially a consanguinity includes M male members and f.f.male members. Each week a member, chosen at random, selects a new member, always of.the same gender as the member making the selection. This model f.r evolution is isomorphic to the classic Pólya’s urn. The male and f.male members play the same roles as the red and black balls in the urn, and the procedure f.r selecting a new member is equivalent to drawing a ball f.om the urn, then replacing it and adding a new ball of.the same color. It is well known that f.r Pólya’s urn, the proportion of.red balls in the urn is a martingale. It f.llows that f.r a consanguinity, the proportion of.the membership that is male is a martingale. f.rthermore, being bounded, this martingale converges to a limit. f.r a martingale that is the sum of.independent random variables, such as a symmetric random walk, there is also a well-known second-degree martingale f.om which the variance of.the limiting distribution can be deduced. What the author discovered, in the process of.solving his own examination problem, is that a similar martingale exists also f.r Pólya’s urn, even though in this case the number of.red balls is the sum of.random variables that are not independent. This new martingale can be used to calculate the variance of.the limiting distribution. Traditionally, the probability that r red balls will be drawn f.om Pólya’s urn in n trials is derived by a rather tricky argument involving conditional probability. This article uses an obvious but overlooked simpler approach. Pólya’s f.rmula f.r the probability that m male members will be chosen in n weeks is derived, without any mention of.conditional probability, by an elementary counting argument, and its limit is shown to be a beta distribution.

关键词： Pólya’s Urn Martingale Martingale Convergence Beta Distribution

Detection of.Adaptive Genetic Diversity in Wild Potato Populations and Its Implications in Conservation of.Potato Germplasm

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American Journal of.Plant Sciences 2020年第10期11卷 1562-1578页

作者： Alf.nso H. del Rio John B. bamberg USDA/Agricultural Research Service US Potato Genebank Sturgeon Bay WI USA

A better understanding on how genetic diversity is structured at natural habitats can be helpf.l f.r exploration and acquisition of.plant germplasm. Historically, studies have relied on DNA markers to elucidate potato genetic diversity. Current advances in genomics are broadening applications allowing the identif.cation of.markers linked to genomic regions under selection. Those markers, known as adaptive markers, unlock additional ways to value and organize germplasm diversity. f.r example, conservation priorities could be given to germplasm units containing markers associated to unique geographic identity, and/or linked to traits of.tolerance to abiotic stresses. This study investigated if.adaptive marker loci were possible to be identif.ed in a large Af.P marker dataset of.ninety-f.ur populations of.the wild potato species S. fendleri. These populations originated from six different mountain ranges in southern Arizona, USA. A total of 2094 polymorphic AFLP markers were used to conduct genetic diversity analyses of populations and mountain ranges. Adaptive markers were detected using Bayesian methods which distinguished marker loci departing significantly from frequencies expected under neutral models of genetic differentiation. This identified 16 AFLP loci that were considered to be adaptive. To contrast diversity pf.nt-f.mily:Verdana;">arameters generated with each set of.markers, analyses that included all the 2094 Af.P markers, and only the 16 adaptive markers were conducted. The results showed that both were ef.icient f.r establishing genetic associations among populations and mountain ranges. However, adaptive markers were better on revealing geographic patterns and identity which would suggest these markers were linked to selection at the natural sites. An additiona

关键词： Adaptive Genetic Diversity Af.P Markers Plant Population Structure Potato Germplasm Solanum f.ndleri

Ef.ects of.the Pesticide <i>f.radan</i>on Traits Associated with Reproduction in Wild Potato Species

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American Journal of.Plant Sciences 2012年第11期3卷 1608-1612页

作者： Alf.nso del Rio John bamberg Ruth Centeno-Diaz Alberto Salas William Roca David Tay International Potato Center (CIP) Lima Peru International Potato Center (CIP) Lima Peru. USDA/Agriculture Research Service US Potato Genebank Wisconsin USA

Natural populations of.wild potato species are the backups f.r the diversity held in genebanks f.r research and breeding. Some potato species are known to grow in close proximity to cultivated f.elds, thus are potentially impacted by human activity, including exposure to pesticides. The present study tested the ef.ects of.a common pesticide on reproductive traits of.potatoes known to grow in or near pesticide-treated f.elds in central Peru. f.radan? 4f. an insecticide— nematicide (common name = carbof.ran) was applied at two dif.erent rates to populations representing 15 wild potato species in a greenhouse environment in Peru. f.owering duration of.these populations was usually signif.cantly reduced in comparison to a water control, and in a f.w cases, percent viable pollen also was. These f.ndings suggest that agrichemicals may be having unintentional ef.ects on wild potato populations in ways that could compromise their genetic diversity.

关键词： Potato Species Pesticide Contamination Genetic Drif. Reproductive Capacity

发现有血流动力学意义的冠状动脉狭窄:动态CT心肌灌注成像有额外诊断价值

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国际医学放射学杂志 2011年第6期 577-578页

作者： f.bamberg A.Becker f.Schwarz R.P.Marcus M.Greif.f.V.Ziegler 王霁朏 Departments of.Clinical Radiology Ludwig-Maximilians UniversityKlinikum GrosshadernMarchioninistrasse 1581377 MunichGermany

目的探讨动态CT心肌灌注成像发现有血流动力学意义的冠状动脉狭窄的可行性,冠状动脉狭窄的血流动力学改变用血流储备分数(f.actional f.ow reserve,f.R)来定义。材料与方法该研究经伦理委员会批准,并获得病人知情同意

关键词：心肌灌注成像血流动力冠状动脉狭窄 CT

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机场自动旅客输送系统规划技术及其应用

城市轨道交通研究 2007年第9期10卷 37-40页

作者：朱忠隆 Wolf.ang bamberg 林晨胡建忠上海市政工程设计研究总院 Lea+Elliott IncAuf'm Graverich 2856179 VallendarGermany 上海机场建设指挥部上海申虹投资发展有限公司

介绍了机场自动旅客输送系统的一般规划技术。规划技术涉及交通规划、运输组织、线路设计、车站布局以及辅助设施规划等内容。该技术方法已应用于上海浦东国际机场自动旅客输送系统的前期规划阶段。本项研究有助于今后国内机场自动旅客... 详细信息

介绍了机场自动旅客输送系统的一般规划技术。规划技术涉及交通规划、运输组织、线路设计、车站布局以及辅助设施规划等内容。该技术方法已应用于上海浦东国际机场自动旅客输送系统的前期规划阶段。本项研究有助于今后国内机场自动旅客输送系统实施建设。

关键词：机场自动旅客输送系统规划技术

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应用交替球管方位的快速双源CT行动态心肌应力灌注成像的初期研究

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国际医学放射学杂志 2010年第4期 396-397页

作者： f.bamberg E.Klotz T.f.ohr A.Becker C.R.Becker B.Schmidt 赵芳 Department of.Clinical Radiology University of Munich Grosshadern CampusMarchioninistrasse 1581377 MunichGermany

目的详述CT定量模型基础上局部心肌血流量(MBf.的原理,并示范其在活体上的应用。方法双源CT扫描采用动态扫描方案,包括每30s于心电图触发收缩末期交替球管方位获

关键词：双源球管灌注成像心肌 CT

比较急性胸痛非洲裔美国人和白种人冠状动脉粥样硬化的冠状动脉CTA表现特征

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国际医学放射学杂志 2011年第5期 482-483页

作者： J.W.Nance f.bamberg U.J.Schoepf.J.M.Barraza J.A.Abro 付娇慧 Heart and Vascular Center Medical University of South CarolinaAshley River Tower25 Courtenay DrMSC 226CharlestonSC 29401

目的利用冠状动脉CT血管成像(CTA)比较研究急性胸痛的非洲裔美国人和白种人之间的动脉粥样硬化斑块病变的发生率、程度与成分。材料与方法本回顾性研究符

关键词：冠状动脉粥样硬化急性胸痛非洲裔美国人美利坚人 CTA 表现特征

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机场旅客捷运系统规划方法研究

机场旅客捷运系统规划方法研究