Time course of foreign gene integration and expression in transgenic fish embryos

Using a nuclear transplantation approach, the integration and expression of the green fluorescent protein (GFP) gene in the embryogenesis of transgenic loach (Misgurnus anguillicaudatus Cantor) have been studied. TheGFP gene expression is first observed at the gastrula stage, which is consistent with the initiation of cell differentiation of fish embryos. The time course of the foreign gene expression is correlated with the regulatory sequences. The expression efficiency also depends on the gene configuration: the expression of pre-integrating circular plasmid at early embryos is higher than that of the linear plasmid. The integration of theGFP gene is first detected at the blastula stage and lasts for quite a long period. When two types of different plasmids are co-injected into fertilized eggs, the behavior of their integration and expression is not identical.     

PDM与ERP的集成

提出ＰＤＭ和ＥＲＰ集成的必要性,分析了ＰＤＭ和ＥＲＰ二系统的区别和信息交汇处,提出二者集成的可能性和困难,指出只要ＰＤＭ和 ＥＲＰ的集成符合企业实际,就是最好的集成方法。     

基于STEP的CAD/CAAPP的信息集成

文章在介绍了CAD系统生成的数据信息和CAAPP的信息需求基础上 ,分析了两者的信息侧重点的差异 ,提出了利用STEP实现CAD与CAAPP信息集成的基本思想及产品装配数据模型 ,论述了基于STEP的CAD/CAAPP集成过程     

港口城市形态与布局规律──以浙江省沿海港口城市为例

以浙江沿海港口城市为研究对象,通过对实地调查所取得的大量具体资料的分析,系统地探讨了浙江沿海港口城市发展的区域背景条件、优势条件和制约因素,分析了浙江沿海港口城市总体布局特征,内部结构形态和外部形态的演变发展规律,提出了浙江沿海港口城市形态与布局变化趋势,为港口城市进一步发展提供理论依据．     

Symmetric Projection Methods for Differential Equations on Manifolds

Projection methods are a standard approach for the numerical solution of differential equations on manifolds. It is known that geometric properties (such as symplecticity or reversibility) are usually destroyed by such a discretization, even when the basic method is symplectic or symmetric. In this article, we introduce a new kind of projection methods, which allows us to recover the time-reversibility, an important property for long-time integrations.     

A new optimal algorithm for weighted approximation and integration over ℝ

The complexities of weighted approximation and weighted integration problems for univariate functions defined over ℝ have recently been found in [7]. Complexity (almost) optimal algorithms have also been provided therein. In this paper, we propose another class of (almost) optimal algorithms that, for a number of instances, are easier to implement. More importantly, these new algorithms have a cost smaller than the original algorithms from [7]. Since both classes of algorithms are (almost) optimal, their costs differ by a multiplicative constant that depends on the specific weight functions and the error demand. In one of our tests we observed this constant to be as large as four, which means a cost reduction by a factor of four. This revised version was published online in June 2006 with corrections to the Cover Date.     

上海国际集装箱枢纽港备选方案比较

针对当前上海建设国际航运中心过程中,对国际集装箱枢纽港选址存在的争议,用层次分析结合专家咨询的方法,对处于争论焦点的三个港口选址方案作了比较分析,结果认为洋山港的建设对上海国际航运中心建设的影响作用最大。     

空间:21世纪的制高点

基于空间优势与信息优势的关系,论述了空间在２１世纪军事斗争中的地位和作用,讨论了航天信息系统的集成问题,最后提出了实现其集成的若干关键技术,包括：频谱利用、宽带传输和网络技术,信息融合技术,安全保密和通信化标准等。     

从“天人合一”看儒学关于人与自然和谐的生态智慧

早在2000多年前,儒学思想家就提出了“天人合一”这一人与自然和谐的哲学命题,从先秦到明清,这种思想为历代儒家学者所阐释和发展。如果我们能结合现代科学文明,从优秀传统文化中发掘更多有价值的思想,那么对当今环境保护与生态建设,促进可持续发展会做出新的贡献。     

基于PDM的集成化CAPP系统

讨论了基于产品数据管理的集成化CAPP系统的总体结构和模块结构 ,并对面向产品的工艺设计、IMAN与AutoCAD之间的通信、CAPP与MRPⅡ之间的集成、版本管理、流程管理、配置管理等关键技术进行了研究 .