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In this article, we propose a stochastic search based method, namely genetic algorithm in conjunction with density functional theory to evaluate structures of water‐halide microclusters, with the halide ion being Cl?, Br?, and I?. Once the structures are established, we evaluate the infrared spectroscopic modes, vertical detachment energies and natural population analysis based charges. We compare our results with available experimental and theoretical results. © 2012 Wiley Periodicals, Inc. 相似文献
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Dr. Toby Passioura Prof. Dr. Hiroaki Suga 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(21):6530-6536
Noncanonical peptides occur frequently in Nature, and often display high bioactivity. However, the lack of tractable systems for the synthesis of diverse libraries of such peptides has thus far hampered their development as drugs. Genetic reprogramming techniques, in which noncanonical amino acids may be incorporated into peptides, have largely removed this limitation. This Concept article outlines the development of these techniques with an emphasis on drug discovery. 相似文献
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该文在免疫遗传算法(IGA)的基础上,提出一种改进免疫遗传算法(iIGA)用于近红外光谱波长变量的选择。该算法舍去了原算法中固定抗体相似度阈值的思想,取而代之的是抗体相似度阈值自适应,同时引入精英保留策略和贪心算法思想,使得算法朝着正确的方向进行局部性探优。将该算法在玉米的淀粉和蛋白质含量数据集上进行实验测试,建立偏最小二乘(PLS)分析模型,并与IGA、遗传算法(GA)以及全谱方法进行了对比。结果表明,在玉米淀粉含量的预测上,iIGA相较于原IGA算法,预测集均方根误差(RMSEP)从0.312 0降至0.298 0,预测集预测精度提升4.5%;在玉米蛋白质含量的预测上,RMSEP从0.124 4降至0.110 3,预测集预测精度提升11.3%。分别对预测淀粉和蛋白质模型的RMSEP值进行显著性检验,F值分别为165.22和182.05,P值分别为9.5 × 10-23和4.5 × 10-24,P值均小于0.05,因此,iIGA能显著提升模型预测精度。 相似文献
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Delaying the human aging process and thus eliminating the risk factors for age-related diseases is one of the prime objectives. While various aging-associated genes and proteins have been characterized, which provide a significant understanding of the human aging process, a significant success in regulating aging is not achieved yet. Understanding how aging proteins interact with each other and also with other proteins could provide important insights into the underlying mechanisms governing the aging process. Therefore, in this work, information of gene expression was included to the static aging-related protein interactome to understand the network-based relationships among aging-related essential (AE) proteins, aging-related non-essential (ANE) proteins, and housekeeping-proteins that could regulate or influence aging. Comprehensive analyses provided various systems-level insights into the regulatory characteristics of aging; for example, (i) network-based correlation analysis predicted functional relationships among AE proteins and ANE proteins; (ii) network variability analysis predicted aging to affect different tissues in strikingly different ways by differentially regulating various regulatory interactions; (iii) cross-network comparisons identified two aging-related modules to be significantly conserved across most of the tissues. Overall, the findings obtained during this study could be helpful for researchers to delay, prevent, or even reverse various aspects of the aging. 相似文献
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S. Rawat 《SAR and QSAR in environmental research》2014,25(7):527-549
Polybrominated diphenyl ethers (PBDEs) are known as effective flame retardants and have vast industrial application in products like plastics, building materials and textiles. They are found to be structurally similar to thyroid hormones that are responsible for regulating metabolism in the body. Structural similarity with the hormones poses a threat to human health because, once in the system, PBDEs have the potential to affect thyroid hormone transport and metabolism. This study was aimed at designing quantitative structure–activity relationship (QSAR) models for predicting toxic endpoints, namely cell viability and apoptosis, elicited by PBDEs in mammalian cells. Cell viability was evaluated quantitatively using a general cytotoxicity bioassay using Janus Green dye and apoptosis was evaluated using a caspase assay. This study has thus modelled the overall cytotoxic influence of PBDEs at an early and a late endpoint by the Genetic Function Approximation method. This research was a twofold process including running in vitro bioassays to collect data on the toxic endpoints and modeling the evaluated endpoints using QSARs. Cell viability and apoptosis responses for Hep G2 cells exposed to PBDEs were successfully modelled with an r2 of 0.97 and 0.94, respectively. 相似文献
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Improving Site‐Directed RNA Editing In Vitro and in Cell Culture by Chemical Modification of the GuideRNA
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Paul Vogel Marius F. Schneider Jacqueline Wettengel Dr. Thorsten Stafforst 《Angewandte Chemie (International ed. in English)》2014,53(24):6267-6271
Adenosine‐to‐inosine deamination can be re‐addressed to user‐defined mRNAs by applying phosphothioate/2′‐methoxy‐modified guideRNAs. Dense chemical modification of the guideRNA clearly improves performance of the covalent conjugates inside the living cell. Furthermore, careful positioning of a few modifications controls editing selectivity in vitro and was exploited for the challenging repair of the Factor 5 Leiden missense mutation. 相似文献
60.
Nanxi Wang Dr. Yue Li Dr. Wei Niu Dr. Ming Sun Dr. Ronald Cerny Prof. Qingsheng Li Prof. Jiantao Guo 《Angewandte Chemie (International ed. in English)》2014,53(19):4867-4871
A safe and effective vaccine against human immunodeficiency virus type 1 (HIV‐1) is urgently needed to combat the worldwide AIDS pandemic, but still remains elusive. The fact that uncontrolled replication of an attenuated vaccine can lead to regaining of its virulence creates safety concerns precluding many vaccines from clinical application. We introduce a novel approach to control HIV‐1 replication, which entails the manipulation of essential HIV‐1 protein biosynthesis through unnatural amino acid (UAA*)‐mediated suppression of genome‐encoded blank codon. We successfully demonstrate that HIV‐1 replication can be precisely turned on and off in vitro. 相似文献