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991.
992.
Impact of a Stereocentre Inversion in Cyclic Lipodepsipeptides from the Viscosin Group: A Comparative Study of the Viscosinamide and Pseudodesmin Conformation and Self‐Assembly
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Niels Geudens Matthias De Vleeschouwer Dr. Krisztina Fehér Dr. Hassan Rokni‐Zadeh Dr. Maarten G. K. Ghequire Prof. Dr. Annemieke Madder Prof. Dr. René De Mot Prof. Dr. José C. Martins Dr. Davy Sinnaeve 《Chembiochem : a European journal of chemical biology》2014,15(18):2736-2746
The viscosin group covers a series of cyclic lipodepsipeptides (CLPs) produced by Pseudomonas bacteria, with a range of biological functions and antimicrobial activities. Their oligopeptide moieties are composed of both L ‐ and D ‐amino acids. Remarkably, the Leu5 amino acid—centrally located in the nonapeptide sequence—is the sole residue found to possess either an L or D configuration, depending on the producing strain. The impact of this D /L switch on the solution conformation was investigated by NMR‐restrained molecular modelling of the epimers pseudodesmin A and viscosinamide A. Although the backbone fold remained unaffected, the D /L switch adjusted the segregation between hydrophobic and hydrophilic residues, and thus the amphipathicity. It also influenced the self‐assembly capacity in organic solvents. Additionally, several new minor variants of viscosinamide A from Pseudomonas fluorescens DR54 were identified, and an NMR assay is proposed to assess the presence of either an L ‐ or D ‐Leu5. 相似文献
993.
介绍了离子膜法烧碱三效自流蒸发工艺流程、设备选材及装置特点,针对运行中存在的问题(如仪表风压低,视镜破裂,预热器管线振动,密封垫片泄漏)提出了改进措施. 相似文献
994.
Dragos Horvath Michael Lisurek Bernd Rupp Ronald Kühne Edgar Specker Jens von Kries Didier Rognan C. David Andersson Fredrik Almqvist Mikael Elofsson Per‐Anders Enqvist Anna‐Lena Gustavsson Nikita Remez Jordi Mestres Gilles Marcou Alexander Varnek Marcel Hibert Jordi Quintana Ronald Frank 《ChemMedChem》2014,9(10):2309-2326
This work describes a collaborative effort to define and apply a protocol for the rational selection of a general‐purpose screening library, to be used by the screening platforms affiliated with the EU‐OPENSCREEN initiative. It is designed as a standard source of compounds for primary screening against novel biological targets, at the request of research partners. Given the general nature of the potential applications of this compound collection, the focus of the selection strategy lies on ensuring chemical stability, absence of reactive compounds, screening‐compliant physicochemical properties, loose compliance to drug‐likeness criteria (as drug design is a major, but not exclusive application), and maximal diversity/coverage of chemical space, aimed at providing hits for a wide spectrum of drugable targets. Finally, practical availability/cost issues cannot be avoided. The main goal of this publication is to inform potential future users of this library about its conception, sources, and characteristics. The outline of the selection procedure, notably of the filtering rules designed by a large committee of European medicinal chemists and chemoinformaticians, may be of general methodological interest for the screening/medicinal chemistry community. The selection task of 200K molecules out of a pre‐filtered set of 1.4M candidates was shared by five independent European research groups, each picking a subset of 40K compounds according to their own in‐house methodology and expertise. An in‐depth analysis of chemical space coverage of the library serves not only to characterize the collection, but also to compare the various chemoinformatics‐driven selection procedures of maximal diversity sets. Compound selections contributed by various participating groups were mapped onto general‐purpose self‐organizing maps (SOMs) built on the basis of marketed drugs and bioactive reference molecules. In this way, the occupancy of chemical space by the EU‐OPENSCREEN library could be directly compared with distributions of known bioactives of various classes. This mapping highlights the relevance of the selection and shows how the consensus reached by merging the five different 40K selections contributes to achieve this relevance. The approach also allows one to readily identify subsets of target‐ or target‐class‐oriented compounds from the EU‐OPENSCREEN library to suit the needs of the diverse range of potential users. The final EU‐OPENSCREEN library, assembled by merging five independent selections of 40K compounds from various expert groups, represents an excellent example of a Europe‐wide collaborative effort toward the common objective of building best‐in‐class European open screening platforms. 相似文献
995.
依据AP1000核电项目建筑结构的特殊性,重点叙述了三门核电一期核岛项目中所用自密实混凝土的配比、运输、施工方法、浇筑区域、养护、质量评定等内容,最后对自密实混凝土的性能表现提出了一些有益的建议。 相似文献
996.
本文主要对建筑工程自组织施工管理模式进行了分析,总结了以自组织理论为基础的管理系统构成,并详细阐述了自组织施工的管理模式,具体内容有管理模式中的项目输入、管理模式中的部门运作、有序升降的次循环单位组成等。 相似文献
997.
One way of adapting and reusing vacant office buildings is conversion into housing. Former research has shown possibilities for this type of conversion, and has delivered instruments for determining the conversion potential of vacant offices. Although adaptation and renovation of outdated offices can prove to be a successful property (real estate) strategy, conversions into housing still only occur on a small scale. There are several reasons for this, including uncertainty about financial feasibility and little knowledge about the opportunities and risks of building conversions. A meta-study of the conversion of 15 office buildings into housing in the Netherlands is used to reveal the drivers for office-to-housing conversions as well as the opportunities and risks that arise in the conversion process. The findings show that various legal, financial, technical, functional and architectonic issues define the opportunities and risks of building conversions. These insights can be used to support the decision-making processes for dealing with vacant office buildings in order to minimize the risks and increase the opportunities. 相似文献
998.
Ecological resilience and resilient cities 总被引:2,自引:0,他引:2
Steward T.A. Pickett Brian McGrath M.L. Cadenasso Alexander J. Felson 《Building Research & Information》2014,42(2):143-157
The urban realm is changing rapidly and becoming increasingly interconnected across continents, and across contrasting types of land covers, while at the same time facing new environmental threats and experiencing new demographic and social pressures. The urban component of the global ecosystem can be made more sustainable by incorporating the ecological understanding of resilience into the discourse. Sustainability is seen as a social, normative goal, which can be promoted using the mechanisms of ecological resilience. Ecological resilience differs from engineering resilience. Ecological resilience emphasizes the capacity of a site to adjust to external shocks and changes in controlling interactions, while engineering resilience emphasizes its ability to return to a state that existed before perturbation. Ecological resilience is particularly appropriate to urban systems, given the extent and open-ended nature of the changes and challenges they face. Adaptive processes are explored as contributions to the achievement of a successful adaptive cycle in urban socio-ecological systems. Key tools for incorporating the ecological thinking about resilience into the social discourse include landscape or patch ecology, the novel idea of the metacity, an assessment of ecological and design models, and the use of designs as experiments. 相似文献
999.
针对气源变化影响全预混冷凝式燃气壁挂炉的燃烧工况,探讨了2种燃气自适应控制方案——离子电流检测法、氧或二氧化碳含量检测法。 相似文献
1000.
María Botn‐Fernndez Miguel A. Vega‐Rodríguez Francisco Prieto Castrillo 《Concurrency and Computation》2015,27(14):3539-3560
Grid computing is considered a promising trend, which enables the sharing of a wide variety of computational and storage resources geographically distributed. Despite the advantages of such paradigm, several problems have emerged during the last decade; most of them caused by an inefficient utilization of grid resources. The present contribution proposes an approach to improve the grid resources selection process. An optimization model for choosing grid resources in an intelligent way has been designed. A mathematical formulation to monitor the resources efficiency has also been established. Furthermore, the model provides a self‐adaptive capability to grid applications, enhancing them for dealing with the changing environmental conditions. The model applies an artificial intelligence algorithm for ensuring an efficient selection. In particular, three different versions have been implemented. Each of them uses a different algorithm. Finally, during the evaluation phase of the model, the experimental tests were performed in a real grid infrastructure. The results show that the model improves the infrastructure throughput, by increasing the finished tasks rate and by reducing the applications execution time. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献