Distribution of YAP in 10 populations of China

The Y-chromosome Alu polymorphism was studied in 10 populations in China. The Alu insertion is present in 54/571 individuals (9%). Among 10 populations, the frequency of YAP element is quite high (49%) in the Tibetans and at moderate or low levels (15%-4%) in the Yi, Hui and Uygur. The Alu insertion is absent in the Han in Guangdong and Shaanxi, and in the Manchu and Zhuang, while a single Tujia individual and a single Yao individual are found to have the Alu insertion.     

浙江省及其临近地区益母草的RAPD分析

运用8个有效的10mer-寡核苷酸引物对浙江省及其邻近地区益母草(Leonurus japonicus)7个居群的基因组DNA进行了RAPD(random amplified polymorphic DNA)扩增，共检测到65个位点，其中多态位点45个，占69．23％。应用Jaccard公式计算了7个居群在65个位点上的相似性，并以此为基础，应用主坐标排序法作出了7个居群遗传分化的三维排序图，结果表明，浙江省及其邻近地区益母草的遗传性状总体较为接近，7个居群的遗传分化与其地理分布有一定的联系。     

有限总体中条件最优预测的稳健性

研究了有限总体中条件最优线性无偏预测的稳健性,得到了条件线性可预测变量的这种预测关于协方差阵具有稳健性的充要条件。     

不同地理种群羊草的形态解剖结构的比较研究

将１９９４年从中科院草原定位站栗钙土,内蒙呼伦贝尔盟尔塔拉黑钙土和从吉林盐碱土上采集的羊草种子行栽培试验,然后分别对这３个不同地理种群羊草的根,茎,叶的横截面和表面进行了电镜扫描观察。结果发现：原生境为不同土壤类型的羊草,其内部的形态结构在根,茎,叶上都发生了一些变化,而且这些变化与其生境有相当的联系。     

中国两性生殖卤虫种群PO同工酶基因的表达特征

采用聚丙烯酰胺凝胶垂直板电泳法对中国两性生殖卤虫 14个品系和伊朗的 1个两性生殖品系的过氧化物酶 ( PO)同工酶基因的表达特征进行了研究 .实验结果表明 :( 1)中国卤虫种群 Artemia sinica各品系和伊朗的 A.urmiana各自有其独特的 PO同工酶基因型 ;( 2 )在两性生殖卤虫各品系 PO同工酶基因表达过程中多数品系 PO-1、PO-3座位均未发现 aa基因型 ;PO-2座位测定不到 aa基因型 ;( 3 )存在品系内和品系间的多态现象 .     

同工酶与林木群体遗传变异研究

<正>同工酶技术应用于林木群体遗传变异研究以来,已取得了很大的进展。本文评述了用同工酶技术研究林木群体遗传变异的情况,并对研究中应注意的几个问题进行了讨论。研究表明,在不同树种中,同工酶的变异水平很高,但林木群体间在同工酶水平上的分化却很低;同工酶技术是评估林木群体变异和分化的有效手段。     

具有一类Holling功能性反应的捕食—被捕食系统的极限环

本文研究一类随着食物量的增加捕食者捕食速度的变化率起变化的种群模型。得到它在R{(x,y):x≥0,y≥0}内存在唯一正平衡点的充要条件和该系统在R内全局渐近稳定的条件,指出其可以出现至少一个(或两个单侧环)或至少两个极限环线的情形以及所存在的极限环的大致位置,从而得出两种群在相互竞争中一种群趋于灭绝或两者互惠共存而达到“生态平衡”的条件。     

定位-车辆路径问题的两阶段混合启发式算法

定位-车辆路径问题(LRP)集成了设施定位分配和车辆路径决策,属于NP-hard难题.为有效求解实际大规模的具有设施容量约束和车辆容量约束的LRP问题,设计了基于禁忌搜索及双种群蚁群算法的两阶段混合启发式算法.算法第1阶段采用禁忌搜索算法确定设施定位及客户分配,算法第2阶段采用双种群蚁群算法优化车辆路径,蚁群间的通信与协调通过信息素共享来实现.通过仿真试验并与其他启发式算法进行对比,结果表明,该算法是可行和有效的.     

Retrospective Testing of Mortality Forecasting Methods for the Projection of Very Elderly Populations in Australia

The purpose of this paper is to present the results of retrospective tests of various extrapolative methods to forecast adult mortality and very elderly populations for Australia. Direct extrapolation methods tested include the Geometric method, Ediev variant, Lee‐Carter method, BMS variant and a relational model. Indirect methods include the extrapolation of parameters of models fitted to the age profile of death rates and a new method involving the extrapolation of features of death frequency distributions namely the modal age and concentration. The geometric, Ediev and Lee‐ Carter BMS methods were very successful in projecting death rates and very elderly populations. Differences between these methods were small. The extrapolation of parametric functions proved successful for males but less so for females. Very elderly populations can be viably projected by directly extrapolating death rates by age when rates of decline in death rates show consistent relationships between ages and are stable over time. Copyright © 2016 John Wiley & Sons, Ltd.