乙酰肉碱的化学合成与酶法拆分

采用化学方法以肉碱为底物, 合成了外消旋乙酰肉碱, 精制后可获得纯度99%以上的乙酰肉碱, 收率为96%. 利用蜗牛酶（Snail Enzyme）对其进行不对称酯水解反应, 发现蜗牛酶对乙酰肉碱具有高度立体选择性, 并且可得到光学纯度为98%的乙酰-L- 肉碱.     

盐和铬对单细胞藻生理生化的影响

以3种单细胞海洋藻类:新月菱形藻、亚心形扁藻、湛江叉鞭金藻为实验材料,研究了几种外界因子6-苄氨基腺嘌呤(6-BA)和二脘基氨基乙醇羧酸酯(DA-6)、盐度、铬等对其生长、光合作用、呼吸作用、叶绿素合成及SOD酶谱的影响.结果表明,在一定的浓度范围内DA-6和6-BA对藻类的生长有促进作用,超过一定浓度,则有抑制作用.在一定的盐度范围内,藻类的增长随着盐度的加大而加快,而超过一定范围,则盐度越大,生长越慢,盐度对藻类光合作用、呼吸作用及叶绿素合成的影响也大致如此.而铬则明显地抑制藻类叶绿素的合成,降低酶活,对藻类有很大的毒害作用.     

无线传感网络可信信息覆盖泰森多边形区域划分算法研究

针对无线传感网络区域划分问题,基于可信信息覆盖模型,设计了一种新的面向可信信息覆盖的泰森多边形区域划分算法。首先,该算法利用节点间的协作感知,通过节点聚类形成节点协作感知盘;然后基于可信信息覆盖模型计算各重建点的权值;最后利用权重泰森多边形图理论设计基于该模型的泰森多边形区域划分算法。仿真实验结果表明,该算法与传统圆盘模型下的泰森多边形法相比较,在相同数量节点下划分的泰森多边形区域数量更少,并且有着更高的覆盖率。     

传感器网络中基于最小覆盖重叠的移动部署

为了优化随机部署的传感器网络的覆盖率,提出了基于最小覆盖重叠(MCO,Minimum Coverage Overlap)的分布式移动部署算法.算法执行时,每个节点根据获得的邻居节点位置信息,计算节点覆盖圆周上覆盖重叠的分布情况,并沿着最大程度减小覆盖重叠的方向移动.通过算法的迭代运行,使网络覆盖重叠程度尽量减小,从而最大限度的优化了网络的覆盖率.仿真结果表明,与基于Voronoi图的算法相比,MCO算法在覆盖率、移动效率、移动距离和部署时间等方面具有更高的性能.     

快鸟数据在光学遥感器成像仿真中的应用

针对早期光学遥感成像模拟软件基于地面图像或机载航空图像的情况,提出针对高分辨率快鸟图像进行航天光学遥感器成像仿真的方法。基于高分辨率快鸟图像,采用ISODATA法进行非监督分类,得到土地分类专题图,通过地物光谱数据库进行反射率转换,从而获得地面反射率图像;利用大气辐射传输软件MODTRAN对其进行大气修正,结合卫星遥感器辐射定标系数,最终得到卫星遥感器输出图像。通过系统仿真结果表明,利用快鸟进行光学遥感器成像仿真为伪装效果检验提供一种有效的手段。     

基于共线度的传感器网络节点定位性能分析

节点定位是无线传感器网络一个很重要的研究内容。提出一种新参数——共线度来分析一组三个参考节点的不同部署对传感器网络节点定位性能的影响,同时从理论上提出并证明了该参数对定位性能影响程度的两个定理。仿真实验显示:该参数有助于分析传感器网络节点的定位性能,并为选择良好的参考节点组合来进行有效定位提供了一个可行的参考指标。     

一种节能的无线传感网异构配置模型

依据对实际传感信息分布与无线传感网络工程需求的分析,提出一种新的无线传感网异构配置模型(WSNHEDPM).对传感节点中的传感模块按需要进行组合,使其与感知物理特征量空间分布特征相适应,以减少信息冗余,降低无线传感节点的能量负担.对两种配置方法进行了配置成本、能量消耗与生存周期方面的理论和实验分析比较.理论和仿真实验表明,该模型使无线传感网在面向实际普通应用环境时更为能量有效和合理.     

Modulation of protein biophysical properties by chemical glycosylation: biochemical insights and biomedical implications

Glycosylation constitutes one of the most important posttranslational modifications employed by biological systems to modulate protein biophysical properties. Due to the direct biochemical and biomedical implications of achieving control over protein stability and function by chemical means, there has been great interest in recent years towards the development of chemical strategies for protein glycosylation. Since current knowledge about glycoprotein biophysics has been mainly derived from the study of naturally glycosylated proteins, chemical glycosylation provides novel insights into its mechanistic understanding by affording control over glycosylation parameters. This review presents a survey of the effects that natural and chemical glycosylation have on the fundamental biophysical properties of proteins (structure, dynamics, stability, and function). This is complemented by a mechanistic discussion of how glycans achieve such effects and discussion of the implications of employing chemical glycosylation as a tool to exert control over protein biophysical properties within biochemical and biomedical applications. Received 15 December 2006; received after revision 28 March 2007; accepted 25 April 2007     

Selectivity determinants of the aldose and aldehyde reductase inhibitor-binding sites

Aldose reductase and aldehyde reductase belong to the aldo-keto reductase superfamily of enzymes whose members are responsible for a wide variety of biological functions. Aldose reductase has been identified as the first enzyme involved in the polyol pathway of glucose metabolism which converts glucose into sorbitol. Glucose over-utilization through the polyol pathway has been linked to tissue-based pathologies associated with diabetes complications, which make the development of a potent aldose reductase inhibitor an obvious and attractive strategy to prevent or delay the onset and progression of the complications. Structural studies of aldose reductase and the homologous aldehyde reductase in complex with inhibitor were carried out to explain the difference in the potency of enzyme inhibition. The aim of this review is to provide a comprehensive summary of previous studies to aid the development of aldose reductase inhibitors that may have less toxicity problems than the currently available ones. Received 4 December 2006; received after revision 12 February 2007; accepted 20 April 2007     

基于Bayes估计的多传感器数据融合方法研究

对多传感器数据融合方法进行研究 ,以 Bayes估计理论为基础得到了多传感器最优融合数据 ,并将它与其它方法得到的融合数据进行了比较 .