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191.
192.
利用Kojima函数的正则性质研究了多目标规划问题的纯量化问题解的强Lipschitz稳定性. 相似文献
193.
Rothberg JM Hinz W Rearick TM Schultz J Mileski W Davey M Leamon JH Johnson K Milgrew MJ Edwards M Hoon J Simons JF Marran D Myers JW Davidson JF Branting A Nobile JR Puc BP Light D Clark TA Huber M Branciforte JT Stoner IB Cawley SE Lyons M Fu Y Homer N Sedova M Miao X Reed B Sabina J Feierstein E Schorn M Alanjary M Dimalanta E Dressman D Kasinskas R Sokolsky T Fidanza JA Namsaraev E McKernan KJ Williams A Roth GT Bustillo J 《Nature》2011,475(7356):348-352
The seminal importance of DNA sequencing to the life sciences, biotechnology and medicine has driven the search for more scalable and lower-cost solutions. Here we describe a DNA sequencing technology in which scalable, low-cost semiconductor manufacturing techniques are used to make an integrated circuit able to directly perform non-optical DNA sequencing of genomes. Sequence data are obtained by directly sensing the ions produced by template-directed DNA polymerase synthesis using all-natural nucleotides on this massively parallel semiconductor-sensing device or ion chip. The ion chip contains ion-sensitive, field-effect transistor-based sensors in perfect register with 1.2 million wells, which provide confinement and allow parallel, simultaneous detection of independent sequencing reactions. Use of the most widely used technology for constructing integrated circuits, the complementary metal-oxide semiconductor (CMOS) process, allows for low-cost, large-scale production and scaling of the device to higher densities and larger array sizes. We show the performance of the system by sequencing three bacterial genomes, its robustness and scalability by producing ion chips with up to 10 times as many sensors and sequencing a human genome. 相似文献
194.
Peça J Feliciano C Ting JT Wang W Wells MF Venkatraman TN Lascola CD Fu Z Feng G 《Nature》2011,472(7344):437-442
Autism spectrum disorders (ASDs) comprise a range of disorders that share a core of neurobehavioural deficits characterized by widespread abnormalities in social interactions, deficits in communication as well as restricted interests and repetitive behaviours. The neurological basis and circuitry mechanisms underlying these abnormal behaviours are poorly understood. SHANK3 is a postsynaptic protein, whose disruption at the genetic level is thought to be responsible for the development of 22q13 deletion syndrome (Phelan-McDermid syndrome) and other non-syndromic ASDs. Here we show that mice with Shank3 gene deletions exhibit self-injurious repetitive grooming and deficits in social interaction. Cellular, electrophysiological and biochemical analyses uncovered defects at striatal synapses and cortico-striatal circuits in Shank3 mutant mice. Our findings demonstrate a critical role for SHANK3 in the normal development of neuronal connectivity and establish causality between a disruption in the Shank3 gene and the genesis of autistic-like behaviours in mice. 相似文献
195.
Bing Joe Hwang Ching Hsiang Chen Loka Subramanyam Sarma Din-gao Liu Jyh Fu Lee 《复旦学报(自然科学版)》2007,46(5)
1 Results Bimetallic particles in the nanometer size range are of substantial interest due to their vast applications in catalysis[1].The synthesis of bimetallic nanoparticles with definite size with a well-control over their nanostructure remains a challenging problem.Thus there exists a great demand for both synthesis and atomic level characterization of nanostructure of bimetallic nanoparticles (NPs).With the recent advent of high-intensity tunable sources of X-rays,now available at synchrotron radia... 相似文献
196.
为研究软弱夹层对边坡失稳的影响,对含软弱夹层的岩体强度及破坏模式进行了理论和试验研究.采用某边坡钻孔芯样分别制备强风化泥岩、泥化夹层、含软弱夹层泥岩3种三轴试样,并进行三轴固结不排水剪试验.结合理论分析,对强风化泥岩、泥化夹层、含软弱夹层泥岩的强度和破坏模式进行了研究,揭示软弱夹层倾角、围压对试样强度和破坏模式的影响规... 相似文献
197.
198.
文中首先根据交叉口交通流参数时间序列的相关性对关联交叉口进行定义,给出关联交叉口短时交通流可预测分析的几个定量指标,以及交通流时间序列最大Lya-punov指数的计算方法;然后提出在短时交通流时间序列的可预测分析基础上,选取一组预测模型并建立基于RBF网络的非线性组合预测模型,提出了关联交叉口短时交通流的组合预测算法;最后对实测短时交通流进行仿真试验,结果表明组合预测方法相对于单项预测方法具有更好的预测性能. 相似文献
199.
粮食产量影响因素的灰色关联分析及其贡献率比较 总被引:4,自引:1,他引:3
运用灰色关联分析的方法,通过对省域(河南省)、市域(安阳市)、县域(滑县)三级粮食产量影响因素(播种面积、有效灌溉面积、农村用电、农用化肥、农用柴油、农药)的灰色关联分析及其贡献率比较,结果表明:有效灌溉面积对市域、省域两级粮食产量的影响均居第一位,农用化肥施用量对县域、市域两级粮食产量的影响均居第二位,农药与其它5个因素相比,对省、市、县三级粮食产量的影响相同,都是最小.农用柴油、农村用电、农用化肥、农药对县、市两级粮食产量的贡献率均居第一、第二、第三、第四位,化肥和农药对省、市、县三级粮食产量的贡献率都据第三和第四位.在此基础上,为不同区域尺度的粮食生产提供了决策依据.表5.参11. 相似文献
200.
Romeo S Pennacchio LA Fu Y Boerwinkle E Tybjaerg-Hansen A Hobbs HH Cohen JC 《Nature genetics》2007,39(4):513-516
Resequencing genes provides the opportunity to assess the full spectrum of variants that influence complex traits. Here we report the first application of resequencing to a large population (n = 3,551) to examine the role of the adipokine ANGPTL4 in lipid metabolism. Nonsynonymous variants in ANGPTL4 were more prevalent in individuals with triglyceride levels in the lowest quartile than in individuals with levels in the highest quartile (P = 0.016). One variant (E40K), present in approximately 3% of European Americans, was associated with significantly lower plasma levels of triglyceride and higher levels of high-density lipoprotein cholesterol in European Americans from the Atherosclerosis Risk in Communities Study and in Danes from the Copenhagen City Heart Study. The ratio of nonsynonymous to synonymous variants was higher in European Americans than in African Americans (4:1 versus 1.3:1), suggesting population-specific relaxation of purifying selection. Thus, resequencing of ANGPTL4 in a multiethnic population allowed analysis of the phenotypic effects of both rare and common variants while taking advantage of genetic variation arising from ethnic differences in population history. 相似文献