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51.
Protein–protein interactions (PPIs) play essential roles in many biological processes. In protein–protein interaction networks, hubs involve in numbers of PPIs and may constitute an important source of drug targets. The intrinsic disorder proteins (IDPs) with unstable structures can promote the promiscuity of hubs and also involve in many disease pathways, so they also could serve as potential drug targets. Moreover, proteins with similar functions measured by semantic similarity of gene ontology (GO) terms tend to interact with each other. Here, the relationship between hub proteins and drug targets based on GO terms and intrinsic disorder was explored. The semantic similarities of GO terms and genes between two proteins, and the rate of intrinsic disorder residues of each protein were extracted as features to characterize the functional similarity between two interacting proteins. Only using 8 feature variables, prediction models by support vector machine (SVM) were constructed to predict PPIs. The accuracy of the model on the PPI data from human hub proteins is as high as 83.72%, which is very promising compared with other PPI prediction models with hundreds or even thousands of features. Then, 118 of 142 PPIs between hubs are correctly predicted that the two interacting proteins are targets of the same drugs. The results indicate that only 8 functional features are fully efficient for representing PPIs. In order to identify new targets from IDP dataset, the PPIs between hubs and IDPs are predicted by the SVM model and the model yields a prediction accuracy of 75.84%. Further research proves that 3 of 5 PPIs between hubs and IDPs are correctly predicted that the two interacting proteins are targets of the same drugs. All results demonstrate that the model with only 8-dimensional features from GO terms and intrinsic disorder still gives a good performance in predicting PPIs and further identifying drug targets. 相似文献
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Stability in terms of two measures of solutions to stochastic partial differential delay equations with switching 下载免费PDF全文
In this paper, the problem of stability in terms of two measures is considered for a class of stochastic partial differential delay equations with switching. Sufficient conditions for stability in terms of two measures are obtained based on the technique of constructing a proper approximating strong solution system and conducting a limiting type of argument to pass on stability of strong solutions to mild ones. In particular, the stochastic stability under the fixed‐index sequence monotonicity condition and under the average dwell‐time switching are considered. 相似文献
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伸缩张量率的抽象表示 总被引:2,自引:0,他引:2
本文用“主轴内蕴法”给出右-左伸缩张量 U 和 V 的时间导数 U 和 V 的抽象表示。文中引进所谓“分离技巧”,使能有效地应用张量函数的标准表示。V 的表达式是新的。还给出U 和 V 的两个新关系式。 相似文献
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In a previous work, a reproducible procedure to produce a new biosynthetic tracer was developed. This new tracer is an MS2 bacteriophage with enzymatic probes grafted on its surface, which can induce enzymatic activity of the tracer. In this paper, the biochemical and physicochemical characteristics of this new tracer are determined. A protocol was developed to determine the specific enzymatic activity kcatTRACER of the tracer, which was found to be 2.93 ± 0.78 × 104 min−1 on average. Physicochemical characterizations of this new tracer showed that it is representative of viruses and may thus be used as a virus surrogate to assess the virus retention of membrane systems inline. Notably, the mean diameter and molecular weight of the tracer were found to be respectively 64.1 ± 0.3 nm and 12140 ± 3654 kDa, which are within the size and molecular weight ranges of pathogenic viruses carried by water. The tracer surface was also studied and revealed the considerable porosity of the grafted probe layer, with a mean porosity of 88%, which could explain why the zeta potential of the tracers (−14.34 ± 1.66 mV) was nearly the same as that of the native MS2 phages. Finally, a comparison between filtration of the reference microorganism used for membrane performance assessment (the MS2 phage) and the tracer suspensions showed the same filtration behaviour. 相似文献
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Fatemeh Shakeri Mehdi Dehghan 《Numerical Methods for Partial Differential Equations》2011,27(5):1055-1071
This article presents a technique based on the hybrid Legendre tau‐finite difference method to solve the fourth order wave equation which arises in the elasto‐plastic‐microstructure models for longitudinal motion of an elasto‐plastic bar. Illustrative examples and numerical results obtained using new technique demonstrate that the proposed approach is efficient in treating longitudinal equation of ealsto‐plastic bar. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 27: 1055–1071, 2011 相似文献
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本文重点解读通信电源用交联聚烯烃绝缘电缆通信行业标准的主要内容,介绍了交联聚烯烃绝缘的技术特点.评述了聚氯乙烯(PVC)绝缘电缆在环保和安全方面存在的不足.通过比较说明了交联聚烯烃绝缘电缆相对于PVC绝缘电缆和非交联的无卤低烟阻燃聚烯烃绝缘电缆所具有的优势.本文还介绍了低压电缆制造技术,特别是交联工艺路线、电缆料添加剂及电缆料配混技术进展等方面的内容,对未来通信电源用电缆的发展以及标准修改内容提出了建议. 相似文献
60.
1932年民国教育部颁布的《化学命名原则》为中文化学名词确立了统一的标准,并对于"元素及化合物定名取字"提出"取字应以谐声为主,会意次之,不重象形"的定名总则.它确立的中文化学名词醇、醛、酮、醚、酯是意译名,这似乎与其音译为主的命名原则相悖.本文讨论了醇、醛、酮、醚、酯的各种历史译名,并分析了它们被《原则》采纳的原因. 相似文献