Genetic background of phenotypic variation

A noteworthy feature of the living world is its bewildering variability. A key issue in several biological disciplines is the achievement of an understanding of the hereditary basis of this variability. Two opposing, but not necessarily irreconcilable conceptions attempt to explain the underlying mechanism. The gene function paradigm postulates that phenotypic variance is generated by the polymorphism in the coding sequences of genes. However, comparisons of a great number of homologous gene and protein sequences have revealed that they predominantly remained functionally conserved even across distantly related phylogenic taxa. Alternatively, the gene regulation paradigm assumes that differences in the cis-regulatory region of genes do account for phenotype variation within species. An extension of this latter concept is that phenotypic variability is generated by the polymorphism in the overall gene expression profiles of gene networks. In other words, the activity of a particular gene is a system property determined both by the cis-regulatory sequences of the given genes and by the other genes of a gene network, whose expressions vary among individuals, too. Novel proponents of gene function paradigm claim that functional genetic variance within the coding sequences of regulatory genes is critical for the generation of morphological polymorphism. Note, however, that these developmental genes play direct regulatory roles in the control of gene expression.     

基于模糊模拟的遗传算法在最短路径问题中的应用

模糊最短路径问题将网络中弧的权值描述成模糊的，突破了传统最短路径问题的局限性，更符合实际网络的要求。采用模糊期望值模型求解最短路径问题，由于模糊变量隶属函数的形式多种多样，对于有些模糊变量，很难求出其具体的期望值，所以本文设计了基于模糊模拟的遗传算法进行求解，获得了良好的效果。     

基板负偏压对铜基体磁控溅射离子镀铝膜相组成的影响

本文主要论述基板员偏压与铜基体磁控溅射离子镀铝膜的关系。磁控溅射离子镀 铝膜不是简单的单质外接铝膜，而是铜和铝组成的合金膜。膜的相组成主要是由基板 负偏压所决定的。在一定的实验条件下，每一种铜－铝合金相的出现都有一临界负偏压 与之对应．     

关于城镇化进程中的思考

分析了城镇化进程中的战略目标，对建设城镇的几个关键问题和城镇化实施问题进行了探讨，指出要全面建设小康社会，必须对大城市进行体制改革，协调中小城市比重，以经济发展为中心，注重各种功能区域建设。     

添加剂对AN多变晶型影响研究

本文运用热分析的方法对四十余种无机、有机添加剂和几种表面活性剂及水分对硝酸铵(AN)晶型转变的影响进行了研究。结果表明这些添加剂对AN的影响应为多种因素的综合结果。     

Natural lymphocytic rosettes in non-operated,thymectomized and bursectomized chickens

Résumé On démontre la présence des lymphocytes capables de faire des rosettes spontanées ou naturelles avec les globules rouges de cobaye, dans le thymus, la bourse de Fabricius, la rate et dans la moelle osseuse des poulets non-immunisés, âgés de 8 semaines. Les effets de la boursectomie et de la thymectomie néonatale chez le poulet, suggèrent l'existence de 2 populations de lymphocytes capables de faire des rosettes, dont l'une thymo-dépendente et l'autre dépendant de la bourse.     

The environment in which lymphocytes differentiate influences their ability to cooperate in vivo

Summary Whether or not parental B lymphocytes cooperate with F1 T lymphocytes depends upon the environment in which parental bone marrow cells differentiate. Only those parental B lymphocytes that have differentiated in the F1 environment are able to cooperate with F1 T lymphocytes.Postdoctoral Investigator supported by Subcontract No. 3322 from the Biology Division of Oak Ridge National Laboratory to the University of Tennessee and by the Fulbright-Hays Program.Operated by the Union Carbide Corporation for the Department of Energy.     

Lead metabolism in lactation

Summary A 2-fold increase in lead absorption was observed in lactating animals which received 2 mg Pb/1 in drinking water. About one-half of the absorbed lead was transferred to the litters.Acknowledgments. This work was partially supported by a research grant from the US Environmental Protection Agency and the US Public Health Service.     

Diurnal fluctuation of sensitivity to noradrenaline in the rat and thyroid adrenal interaction

Summary Diurnal fluctuation of the sensitivity to noradrenaline, which disappeared after thyroidectomy, was restored after novotyrol treatment. Dexamethasone treatment did not result in the restoration of the diurnal fluctuation of noradrenaline calorigenic action in adrenalectomized animals.     

群论解决分子振动问题的一般原理和方法

用群论方法处理多原子分子的振动问题,是群论在化学中的一个重要应用。原以为分子振动是杂乱无章的,但经群论方法的分析,就能揭示振动的规律性,将多原子分子复杂的振动分解为一系列的简单振动——简正振动,并求出分子所具有的不同简正振动的数目及所属的对称类型,确定是否具有红外活性,从而在理论上了解振动光谱的实质。