Development of a competitive exclusion product for poultry meeting the regulatory requirements for registration in the European Union

Competitive exclusion treatment is able to increase the pathogen colonization resistance of day-old chicks by applying probiotic bacteria stabilizing the indigenous microflora. In order to develop a safe microbial feed additive, various bacterial strains were isolated out of the gastrointestinal tract of healthy chickens. One hundred twenty-one representatives were selected based on differences in whole-cell protein patterns and screened for antagonistic properties. Five effective strains (Pediococcus acidilactici, Enterococcus faecium, Bifidobacterium animalis ssp. animalis, Lactobacillus reuteri, and Lactobacillus salivarius ssp. salivarius) exhibited in vitro the ability to inhibit a range of common pathogens and were evaluated with regard to the risks associated with genetic transfer of antibiotic resistances from animals to humans via the food chain. The probiotic strains were sensitive to several clinically effective antibiotics, though some of them showed single resistances. None of the vancomycin-resistant (R) strains carried the enterococcal vanA gene. Two tetracycline R strains were shown to harbor a tet(M)-associated resistance. The strains contained no extrachromosomal DNA and were not able to transfer the resistance by means of conjugation. On basis of the collected data the presence of easy transferable resistances was excluded and the chicken strains were considered to be suitable for the use as feed additive.     

Point pattern matching by relaxation

Let $\text{P}\text{= P}{}_1\text{, …, P}{}_{\mathrm{m}}$ and $\text{Q}\text{= Q}{}_1\text{, …, Q}{}_{\mathrm{n}}$ be two patterns of points. Each pairing (P_i, Q_j) of a point of $\text{P}$ with a point of $\text{Q}$ defines a relative displacement δ_ij of the two patterns. We can define a figure of merit for δ_ij according to how closely other point pairs coincide under δ_ij. If there exists a displacement δ₀ for which $\text{P}$ and $\text{Q}$ match reasonably well, the pairings for which δ_ij ? δ₀ will have high merit scores, while other pairings will not. The scores can then be recomputed, giving weights to the other point pairs based on their own scores; and this process can be iterated. When this is done, the scores of pairs that correspond under δ₀ remain relatively high, while those of other pairs become low. Examples of this method of point pattern matching are given, and its possible advantages relative to other methods are discussed.     

利用MSCONFIG修改WINDOWS98的启动项

本文通过对WINDOWS98中各种启动程序的认识,利用WINDOWS98的系统配置实用程序MSCON鄄FIG来配置电脑的启动项,从而减少系统资源的浪费,达到优化系统性能的功能。windows98的系统配置实用程序MSCONFIG工具提供给用户对注册表数据库操作的一个窗口,使得电脑初学者,摆脱了烦琐的操作,很方便地对自己的计算机进行维护和管理。     

Labeled point pattern matching by fuzzy relaxation

A method of matching labeled point patterns is described on the basis of a fuzzy relaxation. The method is applicable to labeled point patterns which differ by geometrical transformations, such as translation, rotation and scale change. In this method, the point pairs are considered to be the pattern primitives. The pattern primitives are geometrically transformed in the process of relaxation so as to minimize a measure of mismatch between the primitive pairs. The compatible primitive pairs between the two labeled point patterns are established after only a few iterations of relaxation and the corresponding points are obtained from the primitive pairs. As an example, the method is applied to the matching of constellations.     

基于图像配准的数字减影图像增强研究

提出了一种基于图像配准的数字减影图像增强算法,通过选择合适的控制点和相似尺度,并采用快速样条插值算法以及鲍威尔优化搜索方法,用块匹配方法对造影图像和掩膜图像配准,配准后的减影图像质量良好,并且该算法具有较快的计算速度。     

基于复形法配准工业产品CT切片模型和CAD模型

在对工业产品进行体积CT扫描时．会存在定住偏差问题，所以工业产品CT切片模型与其CAD模型之间的配准是必不可少的。首先从CT切片模型的表面选取n个点，再把这n个点到CAD模型的距离平方和作为目标函数，通过复形法搜索目标函数极小值，就可求出空间变换的位置匹配参数和角度匹配参数。仿真结果表明．利用复形法可得到满意的结果。     

精铸涡轮叶片的误差分析技术

针对精铸涡轮叶片的检测和模具型腔设计中存在的精度控制问题,运用配准技术来进行误差分析,分别以形心、收缩中心、中心轴线点为特征点,运用CAD模型引导的最临近点迭代ICP(iterative closet point)配准方法,将叶片实际测量数据和CAD模型进行配准。对比配准结果,得到了精铸过程中误差分布,并通过分析叶片的变形情况,得出以形心为特征点时,型面重合度最大,配准效果最好,为叶片精铸模具的型腔设计提供了量化的参考依据。     

我国CDM发展现状、存在的问题及对策研究

清洁发展机制是全球温室气体排放的市场化解决机制之一,在降低发达国家减排成本的同时,也可为发展中国家带来额外资金和先进技术,实现环境和发展的双赢。我国目前已经成为世界最大的CDM供应方,CDM给我国带来了发展契机,但是在我国CDM的发展过程中,出现了地域分布失衡、项目类型单一等方面的问题,需要对此予以完善。