求解加工中心组成问题的新的遗传算法

对成组技术中加工中心组成问题进行研究,在满足各中心机器间相似系数最大的情况下寻求最优组成方案.提出了一种新的求解成组技术中加工中心组成问题的遗传算法.该算法包括建立问题数学模型、提出新的基因编码方法及建立新的基因值与问题解的映射方法,同时设置了合适的适应度函数和遗传运算,最后利用实例对算法进行测试.结果表明:该算法可对具体的问题求解并筛选出最优的求解方案.     

Sex determination in beef by melting curve analysis of PCR amplicons from the amelogenin locus

Sex determination of beef is important to meet the rules of the Commission Regulation (EC) 765/2002 that qualify for export refunds. A SYBR Green sex identification assay based on melting curve analysis of PCR amplicons from the amelogenin locus (AMELX and AMELY) was developed. The PCR amplicons of 130/130 and 130/67 base pairs produced from female and male beef, respectively, are easily distinguished by both melting curve analysis and gel electrophoresis. Results from the melting curve analysis of amplicons are ready in less than three minutes, and requires no additional work in addition to the PCR setup. Applicability of the sex determination assay was studied by analysis of 12 unknown beef samples and the results were compared to an accredited method based on gel electrophoresis. In addition, six different cattle breeds were examined. All test results were correct in respect to sex.     

Isolation and Identification of Potential Beer‐Spoilage Pediococcus inopinatus and Beer‐Spoilage Lactobacillus backi Strains Carrying the horA and horC Gene Clusters

Four beer‐spoilage strains, LA20, LA21, LA22 and LA23, were isolated from brewery environments. Based on the 16S rRNA gene sequence, LA20 was identified as Pediococcus inopinatus and the remaining three were identified as Lactobacillus backi. The homologs of horA and horC, the hop resistance genes originally identified in L. brevis ABBC45, were detected simultaneously in LA22 and LA23, while only a horA homolog and a horC homolog were found in LA20 and LA21 respectively. The 5.6 kb DNA regions containing the horA homolog in LA20 and LA22 were almost 99% identical with the corresponding region of ABBC45. Similarly the 8.2 kb regions containing the horC homolog in LA21 and LA22 were more than 99% identical with that of ABBC45. Interestingly the horA‐containing 5.6 kb regions in LA20 and LA22 were found to be completely identical despite the distinct genus status. Coupled with the fact that LA20 and LA22 were isolated from the same sampling site, these results, taken collectively, reinforce our hypothesis that horA and horC genes were acquired by beer‐spoilage species through horizontal gene transfer and confirm the usefulness of horA and horC as genetic markers for the species‐independent determination of beer‐spoilage ability in lactic acid bacteria.     

Investigating the genetic polymorphism of sheep milk proteins: a useful tool for dairy production

Sheep is the second most important dairy species after cow worldwide, and especially in the Mediterranean and Middle East regions. In some countries, the difficult environmental conditions require a peculiar adaptation and, in these contexts, sheep are able to provide higher quality protein than cattle. In the least‐developed countries, the amount of dairy sheep and ovine milk production is progressively increasing. In order to improve dairy productions, in particular those with local connotations, it is necessary to obtain in‐depth information regarding milk quality and rheological properties. The genetic polymorphisms of milk proteins are often associated with quantitative and qualitative parameters in milk and are potential candidate markers that should be included in breeding strategies similar to those already available for cattle. Due to the current and growing interest in this topic and considering the large amount of new information, the aim of this study was to review the literature on sheep milk protein polymorphisms with a particular emphasis on recent findings in order to give scientists useful support. Moreover, the effects of different protein variants on milk yield and composition are discussed. © 2014 Society of Chemical Industry     

Application of Molecular Marker Assisted Selection in Gene Pyramiding and Selection of New Cultivars

The feasibility of molecule markers' application in gene pyramiding has been proved, and obvious progresses in crop breeding have been made till now. Furthermore, different QTLs or molecular markers linked tightly to yield, quality or resistance may be used for marker assisted selection. MAS will be applied widely in crop breeding due to the development of more gene-based markers and efficient quantitative trait locus (QTL) as well as lower cost marking systems.     

转基因产品中外源基因克隆、转化体系的建立

对所用的受体载体、克隆位点、感受态细胞的制备、转化方法、以及质粒的提取方法进行了筛选,建立了一套适于外源基因克隆、转化的体系,为下一步将转基因产品中常见外源基因转化到同一受体菌中做好准备。     

Absence of Effect after Introducing Bacillus thuringiensis Gene on Nutritional Composition in Cottonseed

ABSTRACT To assess the effect of nutritional composition of cottonseed after introducing Bacillus thuringiensis gene, compositional analyses of Bollgard II cotton event 15985, DPH37B, and 5415 were carried out. Cotton DPH37B contains cry1Ac gene, and Bollgard II 15985 contains cry2Ab and cry1Ac genes. Cotton 5415 was a control. Crude protein, crude fiber, fat, moisture, ash, amino acids level, and selected minerals were measured by chemical analysis. Anti‐nutrients including free gossypol, total gossypol, and tannin were also measured. The results showed that the compositional components of the transgenic cottonseed were comparable to those of the nontransgenic cottonseed. The results of numerous qualitative and quantitative analyses revealed that the transgenic cottonseed was compositionally equivalent to the conventional counterpart.