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排序方式: 共有133条查询结果,搜索用时 15 毫秒
121.
1 Results Electrospinning has attracted immense attention recently as a versatile and easy method to prepare polymer membranes that are made up of thin fibers of micron and sub-micron diameters.Such membranes are particularly suitable as host matrices for polymer electrolytes (PEs) since the interlaying of fibers generate large porosity with fully interconnected pore structure facilitating the easy transport of ions.Characterization of PEs based on electrospun membranes of poly(vinylidene fluoride) (PVd... 相似文献
122.
Jorge?D.?CambaEmail author Manuel?Contero Gustavo?Salvador-Herranz Raquel?Plumed 《系统科学与系统工程学报(英文版)》2016,25(2):142-158
The connection of resources, data, and knowledge through communication technology plays a vital role in current collaborative design methodologies and Product Lifecycle Management (PLM) systems, as these elements act as channels for information and meaning. Despite significant advances in the area of PLM, most communication tools are used as separate services that are disconnected from existing development environments. Consequently, during a communication session, the specific elements being discussed are usually not linked to the context of the discussion, which may result in important information getting lost or becoming difficult to access. In this paper, we present a method to add synchronous communication functionality to a PLM system based on annotated information embedded in the CAD model. This approach provides users a communication channel that is built directly into the CAD interface and is valuable when individuals need to be contacted regarding the annotated aspects of a CAD model. We present the architecture of a new system and its integration with existing PLM systems, and describe the implementation details of an annotation-based video conferencing module for a commercial CAD application. 相似文献
123.
Classifying Time Series Data: A Nonparametric Approach 总被引:1,自引:1,他引:0
124.
Zody MC Garber M Adams DJ Sharpe T Harrow J Lupski JR Nicholson C Searle SM Wilming L Young SK Abouelleil A Allen NR Bi W Bloom T Borowsky ML Bugalter BE Butler J Chang JL Chen CK Cook A Corum B Cuomo CA de Jong PJ DeCaprio D Dewar K FitzGerald M Gilbert J Gibson R Gnerre S Goldstein S Grafham DV Grocock R Hafez N Hagopian DS Hart E Norman CH Humphray S Jaffe DB Jones M Kamal M Khodiyar VK LaButti K Laird G Lehoczky J Liu X Lokyitsang T Loveland J Lui A Macdonald P Major JE Matthews L Mauceli E 《Nature》2006,440(7087):1045-1049
Chromosome 17 is unusual among the human chromosomes in many respects. It is the largest human autosome with orthology to only a single mouse chromosome, mapping entirely to the distal half of mouse chromosome 11. Chromosome 17 is rich in protein-coding genes, having the second highest gene density in the genome. It is also enriched in segmental duplications, ranking third in density among the autosomes. Here we report a finished sequence for human chromosome 17, as well as a structural comparison with the finished sequence for mouse chromosome 11, the first finished mouse chromosome. Comparison of the orthologous regions reveals striking differences. In contrast to the typical pattern seen in mammalian evolution, the human sequence has undergone extensive intrachromosomal rearrangement, whereas the mouse sequence has been remarkably stable. Moreover, although the human sequence has a high density of segmental duplication, the mouse sequence has a very low density. Notably, these segmental duplications correspond closely to the sites of structural rearrangement, demonstrating a link between duplication and rearrangement. Examination of the main classes of duplicated segments provides insight into the dynamics underlying expansion of chromosome-specific, low-copy repeats in the human genome. 相似文献
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126.
Butland G Peregrín-Alvarez JM Li J Yang W Yang X Canadien V Starostine A Richards D Beattie B Krogan N Davey M Parkinson J Greenblatt J Emili A 《Nature》2005,433(7025):531-537
Proteins often function as components of multi-subunit complexes. Despite its long history as a model organism, no large-scale analysis of protein complexes in Escherichia coli has yet been reported. To this end, we have targeted DNA cassettes into the E. coli chromosome to create carboxy-terminal, affinity-tagged alleles of 1,000 open reading frames (approximately 23% of the genome). A total of 857 proteins, including 198 of the most highly conserved, soluble non-ribosomal proteins essential in at least one bacterial species, were tagged successfully, whereas 648 could be purified to homogeneity and their interacting protein partners identified by mass spectrometry. An interaction network of protein complexes involved in diverse biological processes was uncovered and validated by sequential rounds of tagging and purification. This network includes many new interactions as well as interactions predicted based solely on genomic inference or limited phenotypic data. This study provides insight into the function of previously uncharacterized bacterial proteins and the overall topology of a microbial interaction network, the core components of which are broadly conserved across Prokaryota. 相似文献
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128.
Tovar J León-Avila G Sánchez LB Sutak R Tachezy J van der Giezen M Hernández M Müller M Lucocq JM 《Nature》2003,426(6963):172-176
Giardia intestinalis (syn. lamblia) is one of the most widespread intestinal protozoan pathogens worldwide, causing hundreds of thousands of cases of diarrhoea each year. Giardia is a member of the diplomonads, often described as an ancient protist group whose primitive nature is suggested by the lack of typical eukaryotic organelles (for example, mitochondria, peroxisomes), the presence of a poorly developed endomembrane system and by their early branching in a number of gene phylogenies. The discovery of nuclear genes of putative mitochondrial ancestry in Giardia and the recent identification of mitochondrial remnant organelles in amitochondrial protists such as Entamoeba histolytica and Trachipleistophora hominis suggest that the eukaryotic amitochondrial state is not a primitive condition but is rather the result of reductive evolution. Using an in vitro protein reconstitution assay and specific antibodies against IscS and IscU--two mitochondrial marker proteins involved in iron-sulphur cluster biosynthesis--here we demonstrate that Giardia contains mitochondrial remnant organelles (mitosomes) bounded by double membranes that function in iron-sulphur protein maturation. Our results indicate that Giardia is not primitively amitochondrial and that it has retained a functional organelle derived from the original mitochondrial endosymbiont. 相似文献
129.
Optimization of an innovative approach involving mechanical activation and acid digestion for the extraction of lithium from lepidolite 下载免费PDF全文
Nathália Vieceli Carlos A. Nogueira Manuel F. C. Pereira Fernando O. Dur o Carlos Guimar es Fernanda Margarido 《矿物冶金与材料学报》2018,25(1):11-19
The recovery of lithium from hard rock minerals has received increased attention given the high demand for this element. Therefore, this study optimized an innovative process, which does not require a high-temperature calcination step, for lithium extraction from lepidolite. Mechanical activation and acid digestion were suggested as crucial process parameters, and experimental design and response-surface methodology were applied to model and optimize the proposed lithium extraction process. The promoting effect of amorphization and the formation of lithium sulfate hydrate on lithium extraction yield were assessed. Several factor combinations led to extraction yields that exceeded 90%, indicating that the proposed process is an effective approach for lithium recovery. 相似文献
130.
The common biology of cancer and ageing 总被引:1,自引:0,他引:1
At first glance, cancer and ageing would seem to be unlikely bedfellows. Yet the origins for this improbable union can actually be traced back to a sequence of tragic--and some say unethical--events that unfolded more than half a century ago. Here we review the series of key observations that has led to a complex but growing convergence between our understanding of the biology of ageing and the mechanisms that underlie cancer. 相似文献