Reconstruction of linkage maps in the distorted segregation populations of backcross, doubled haploid and recombinant inbred lines

Non-Mendelian segregation of markers, known as distorted segregation, is a common biological phenomenon. Although segregation distortion affects the estimation of map distances and the results of quantitative trait loci (QTL) mapping, the effects of distorted markers are often ignored in the construction of linkage maps and in QTL mapping. Recently, we have developed a multipoint method via a Hidden Markov chain method to reconstruct linkage maps in an F2 population that corrects for bias of map distances between distorted markers. In this article, the method is extended to cover backcross, doubled haploid and recombinant inbred line (RIL) populations. The results from simulated experiments show that: (1) the degree that two linked segregation distortion loci (SDL) affect the estimation of map distances increases as SDL heritability and interval length between adjacent markers increase, whereas sample size has little effect on the bias; (2) two linked SDL result in the underesti- mation of linkage distances for most cases, overestimation for an additive model with opposite additive effects, and unbiased estimation for an epistatic model with negative additive-by-additive effects; (3) the proposed method can obtain the unbiased estimation of linkage distance. This new method was applied to a rice RIL population with severely distorted segregation to reconstruct the linkage maps, and a bootstrap method was used to obtain 95% confidence intervals of map distances. The results from real data analysis further demonstrate the utility of our method, which provides a foundation for the inheritance analysis of quantitative and viability traits.     

浅谈山区公路定线

按公路建设基本程序,公路初步设计审批后,即进入到路线的详测阶段,以便完成公路路线施工图设计。公路路线的勘测设计是公路建设的关键工作,而在详测阶段,公路的定线是整个详测工作的关键。     

浅析Autodesk Map 3D 在数字测图中的应用

文章通过对Autodesk Map 3D的主要功能的分析,介绍了它在数字测图中的一些具体应用,重点讨论了在土方量计算以及等高线绘制中应用问题。     

路与轮联图的邻强边色数

对一个正常的边染色满足相邻点的色集不同的条件时，称为邻强边染色，其所用最少染色数称为邻强边色数。就路与轮的联图，得到了在m,n任意取值情况下的邻强边色数。     

变频调速技术在细纱机恒张力控制中的应用

根据纱线长度，用变频器控制细纱机主轴转速，设计了纺纱过程中纱线恒张力控制．程序按照状态变化进行设计开发．实验结果表明，该设计达到设计要求．其产品已投入批量生产．     

一类广义Petersen图的邻强边染色

研究了一类广义Petersen图G(n,k)的邻强边染色,构造性地证明了:若n≡0(mod3),k≡/0(mod3),则χ_(as)~′(G(n,k))=4.其中χa′s(G(n,k))表示G(n,k)的邻强边色数.     

关于C_m∨K_(1,n)的邻强边色数

对一个正常边染色满足相邻点的色集不同,称为邻强边染色,其所用最少染色数称为邻强边色数.就圈Cm与星K1,n的联图CmVK1,n,文章中得到了在m,n不同取值情况下的邻强边色数.     

广义幂级数环的零因子图

研究了广义幂级数环[[R^s≤]]的零因子图的直径与围长等基本性质．当S为平凡序挠自由可消幺半群时，获得了[[R^s≤]]（即幺半群环R[S]）的零因子图的若干性质．     

非基本最短欧几里德2-连通Steiner网络的几个性质

欧几里德2-连通Steiner网络问题是组合优化中的著名问题,在水、电供应网络等的设计中有非常广泛的应用.以块图为工具,证明了非基本最短欧几里德2-连通Steiner网络的一些结构性质.     

UML 2.0通信图的一种测试用例生成方法

提出了一种UML2.0通信图生成测试用例的方法.首先根据通信图构建一棵通信树,利用后序遍历了所构造的树,从通信图中选择条件断言,然后转换条件断言并通过求解函数最小值的方法来生成测试用例.该测试用例满足消息路径覆盖和边界覆盖.