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排序方式: 共有226条查询结果,搜索用时 15 毫秒
211.
Jinghui Li Rui Kang Ali Mosleh Xing Pan .School of Reliability Systems Engineering Beihang University Beijing P.R.China .Center for Risk Reliability University of Maryl College Park MD USA 《系统工程与电子技术(英文版)》2011,(6):1015-1022
This paper presents a methodology for automatically generating risk scenarios for dynamic reliability applications in which some dynamic characteristics(e.g.,the order,timing and magnitude of events,the value of relevant process parameters and initial conditions) have a significant influence on the evolution of the system.The main idea of the methodology is:(i) making the system model "express itself" through simulation by having the model driven by an elaborated simulation engine;(ii) exploiting uniform design to pick out a small subset of representative design points from the space of relevant dynamic characteristics;(iii) for each selected design point,employing a depth-first systematic exploration strategy to cover all possible scenario branches at each branch point.A highly dynamic example adapted from the literature(a chemical batch reactor) is studied to test the effectiveness of the proposed methodology. 相似文献
212.
213.
Scherer SE Muzny DM Buhay CJ Chen R Cree A Ding Y Dugan-Rocha S Gill R Gunaratne P Harris RA Hawes AC Hernandez J Hodgson AV Hume J Jackson A Khan ZM Kovar-Smith C Lewis LR Lozado RJ Metzker ML Milosavljevic A Miner GR Montgomery KT Morgan MB Nazareth LV Scott G Sodergren E Song XZ Steffen D Lovering RC Wheeler DA Worley KC Yuan Y Zhang Z Adams CQ Ansari-Lari MA Ayele M Brown MJ Chen G Chen Z Clerc-Blankenburg KP Davis C Delgado O Dinh HH Draper H Gonzalez-Garay ML Havlak P Jackson LR Jacob LS 《Nature》2006,440(7082):346-351
Human chromosome 12 contains more than 1,400 coding genes and 487 loci that have been directly implicated in human disease. The q arm of chromosome 12 contains one of the largest blocks of linkage disequilibrium found in the human genome. Here we present the finished sequence of human chromosome 12, which has been finished to high quality and spans approximately 132 megabases, representing approximately 4.5% of the human genome. Alignment of the human chromosome 12 sequence across vertebrates reveals the origin of individual segments in chicken, and a unique history of rearrangement through rodent and primate lineages. The rate of base substitutions in recent evolutionary history shows an overall slowing in hominids compared with primates and rodents. 相似文献
214.
Arsenite transport in plants 总被引:2,自引:0,他引:2
Waqar Ali Stanislav V. Isayenkov Fang-Jie Zhao Frans J. M. Maathuis 《Cellular and molecular life sciences : CMLS》2009,66(14):2329-2339
Arsenic is a metalloid which is toxic to living organisms. Natural occurrence of arsenic and human activities have led to
widespread contamination in many areas of the world, exposing a large section of the human population to potential arsenic
poisoning. Arsenic intake can occur through consumption of contaminated crops and it is therefore important to understand
the mechanisms of transport, metabolism and tolerance that plants display in response to arsenic. Plants are mainly exposed
to the inorganic forms of arsenic, arsenate and arsenite. Recently, significant progress has been made in the identification
and characterisation of proteins responsible for movement of arsenite into and within plants. Aquaporins of the NIP (nodulin26-like
intrinsic protein) subfamily were shown to transport arsenite in planta and in heterologous systems. In this review, we will
evaluate the implications of these new findings and assess how this may help in developing safer and more tolerant crops. 相似文献
215.
Systemic Practice and Action Research - Action research studies in education often address learners’ needs and empower practitioners to effectively change instructional practices and school... 相似文献
216.
Oaks JL Gilbert M Virani MZ Watson RT Meteyer CU Rideout BA Shivaprasad HL Ahmed S Chaudhry MJ Arshad M Mahmood S Ali A Khan AA 《Nature》2004,427(6975):630-633
217.
Ali K Bilancio A Thomas M Pearce W Gilfillan AM Tkaczyk C Kuehn N Gray A Giddings J Peskett E Fox R Bruce I Walker C Sawyer C Okkenhaug K Finan P Vanhaesebroeck B 《Nature》2004,431(7011):1007-1011
Inflammatory substances released by mast cells induce and maintain the allergic response. Mast cell differentiation and activation are regulated, respectively, by stem cell factor (SCF; also known as Kit ligand) and by allergen in complex with allergen-specific immunoglobulin E (IgE). Activated SCF receptors and high-affinity receptors for IgE (FcvarepsilonRI) engage phosphoinositide 3-kinases (PI(3)Ks) to generate intracellular lipid second messenger signals. Here, we report that genetic or pharmacological inactivation of the p110delta isoform of PI(3)K in mast cells leads to defective SCF-mediated in vitro proliferation, adhesion and migration, and to impaired allergen-IgE-induced degranulation and cytokine release. Inactivation of p110delta protects mice against anaphylactic allergic responses. These results identify p110delta as a new target for therapeutic intervention in allergy and mast-cell-related pathologies. 相似文献
218.
The male-specific region of the human Y chromosome is a mosaic of discrete sequence classes 总被引:2,自引:0,他引:2
Skaletsky H Kuroda-Kawaguchi T Minx PJ Cordum HS Hillier L Brown LG Repping S Pyntikova T Ali J Bieri T Chinwalla A Delehaunty A Delehaunty K Du H Fewell G Fulton L Fulton R Graves T Hou SF Latrielle P Leonard S Mardis E Maupin R McPherson J Miner T Nash W Nguyen C Ozersky P Pepin K Rock S Rohlfing T Scott K Schultz B Strong C Tin-Wollam A Yang SP Waterston RH Wilson RK Rozen S Page DC 《Nature》2003,423(6942):825-837
219.
Résumé Les Fréquences de Fusion de l'Electrorétinogramme (FFF) ont été enregistrées chez les truites mouchetées (Salvelinus fontinalis) normales et albinos. Chez les poissons adaptés à la lumière ainsi qu'à l'obscurité les valeurs sont plus élevées chez les albinos que chez les animaux normaux. Les valeurs maximum de FFF sont aussi atteintes à des intensités moins élevées chez les albinos. Ces différences sont attribuables à l'entrée d'une plus grande quantité de lumière ainsi qu'à sa réflection par la sclérotique, ce qui est due au manque de pigment épithelial rétinien. 相似文献
220.
Marjan Radi Behnam Dezfouli Kamalrulnizam Abu Bakar Shukor Abd Razak Mohammad Ali Nematbakhsh 《清华大学学报》2011,16(5):475-490
The existing multipath routing protocols for wireless sensor networks demonstrate the efficacy of traffic distribution over multiple paths to fulfill the Quality of Service (QoS) requirements of different applications.However,the performance of these protocols is highly affected by the characteristics of the wireless channel and may be even inferior to the performance of single-path approaches.Specifically,when multiple adjacent paths are being used concurrently,the broadcast nature of wireless channels res... 相似文献