多层交换技术在宽带防火墙系统中的应用

随着网络的宽带化,传统的防火墙已经无法适应这样的变化。对于防火墙来说,需要支持1G,甚或10G这样的链路。无论是基于包过滤的防火墙,还是基于应用网关的防火墙都必须满足这样的要求。文章利用作者研究的高性能包分类算法和基于粘结的技术可以极大地提高基于包过滤和应用网关防火墙的性能。在一个商业化的防火墙的环境下测试了采用新包分类算法和基于粘结技术的原型的性能。在目前的测试环境下,根据理论分析,可以达到1G的性能。     

某框架—剪力墙结构的鉴定与加固设计

通过对某停建多年建筑物的安全性鉴定，发现已建楼层的部分梁、柱、剪力墙等构件存在结构安全问题，并对该部分构件分别采用几种可行的加固措施进行处理,同时，还对续建楼层的钢筋连接提出了解决的方法。     

光纤接续质量的控制

介绍了光缆施工维护中的技术标准与要求,以及如何提高光纤和光缆的接续质量及接续中应注意的问题,对正确、规范和高质量的光缆接续,延长光缆的使用寿命,减少光缆故障,确保通信畅通,将起到重要作用.     

常用角钢接头长度的简化计算

针对在钢结构的加工及安装过程中经常碰到的角钢拼接问题,根据GB 50017-2003钢结构设计规范,通过强度计算,提出等边或不等边角钢的拼接接头简化计算公式,以期作为工程实践的技术依据。     

Minor Intron Splicing from Basic Science to Disease

Pre-mRNA splicing is an essential step in gene expression and is catalyzed by two machineries in eukaryotes: the major (U2 type) and minor (U12 type) spliceosomes. While the majority of introns in humans are U2 type, less than 0.4% are U12 type, also known as minor introns (mi-INTs), and require a specialized spliceosome composed of U11, U12, U4atac, U5, and U6atac snRNPs. The high evolutionary conservation and apparent splicing inefficiency of U12 introns have set them apart from their major counterparts and led to speculations on the purpose for their existence. However, recent studies challenged the simple concept of mi-INTs splicing inefficiency due to low abundance of their spliceosome and confirmed their regulatory role in alternative splicing, significantly impacting the expression of their host genes. Additionally, a growing list of minor spliceosome-associated diseases with tissue-specific pathologies affirmed the importance of minor splicing as a key regulatory pathway, which when deregulated could lead to tissue-specific pathologies due to specific alterations in the expression of some minor-intron-containing genes. Consequently, uncovering how mi-INTs splicing is regulated in a tissue-specific manner would allow for better understanding of disease pathogenesis and pave the way for novel therapies, which we highlight in this review.     

抗体重链轻链可变区连接条件的优化

采用重叠延伸PCR(SOE-PCR)法拼接VH、Linker、VL,优化了SOE-PCR中模板量、引物量、退火温度及DNA聚合酶量。确定了优化的连接条件为:50μL反应体系中,SfiI-VH-Linker-232ng,Linker+-VL-NotI 200ng,于64.8℃退火,7个循环后,各加入上下游引物1.5μL(10μmol·L-1),再另加PrimeSTAR HS DNA Polymerase 0.5μL,于62.0℃退火,扩增25个循环。在改进后的连接条件下,可获得高纯度、高丰度的扩增产物,利于抗体库的多样性。     

载重子午线轮胎胎体成型稀线的原因分析及解决措施

分析载重子午线轮胎胎体成型稀线的原因并提出解决措施.分析表明,造成轮胎成型稀线的主要原因是接头机工作不稳定,通过对电动接头机和帘布自动裁刀进行改进、规范接头机工艺参数、制定标准化作业指导书和建立过程监控制度等措施,有效地防止了稀线废次品的产生.     

Investigation of Serine‐Proteinase‐Catalyzed Peptide Splicing in Analogues of Sunflower Trypsin Inhibitor 1 (SFTI‐1)

Serine‐proteinase‐catalyzed peptide splicing was demonstrated in analogues of the trypsin inhibitor SFTI‐1: both single peptides and two‐peptide chains (C‐ and N‐terminal peptide chains linked by a disulfide bridge). In the second series, peptide splicing with catalytic amount of proteinase was observed only when formation of acyl–enzyme intermediate was preceded by hydrolysis of the substrate Lys–Ser peptide bond. Here we demonstrate that with an equimolar amount of the proteinase, splicing occurs in all the two‐peptide‐chain analogues. This conclusion was supported by high resolution crystal structures of selected analogues in complex with trypsin. We showed that the process followed a direct transpeptidation mechanism. Thus, the acyl–enzyme intermediate was formed and was immediately used for a new peptide bond formation; products associated with the hydrolysis of the acyl–enzyme were not observed. The peptide splicing was sequence‐ not structure‐specific.