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371.
Da Jiang Yinping Pan Shiyuan Wang Yishi Lin Connor M.Holland John R.Kirtley Xianhui Chen Jun Zhao Lei Chen Shaoyu Yin Yihua Wang 《科学通报(英文版)》2021,(5):425-432
The iron-chalcogenide high temperature superconductor Fe(Se,Te) (FST) has been reported to exhibit complex magnetic ordering and nontrivial band topology which ... 相似文献
372.
373.
Genome sequencing in microfabricated high-density picolitre reactors 总被引:21,自引:0,他引:21
Margulies M Egholm M Altman WE Attiya S Bader JS Bemben LA Berka J Braverman MS Chen YJ Chen Z Dewell SB Du L Fierro JM Gomes XV Godwin BC He W Helgesen S Ho CH Ho CH Irzyk GP Jando SC Alenquer ML Jarvie TP Jirage KB Kim JB Knight JR Lanza JR Leamon JH Lefkowitz SM Lei M Li J Lohman KL Lu H Makhijani VB McDade KE McKenna MP Myers EW Nickerson E Nobile JR Plant R Puc BP Ronan MT Roth GT Sarkis GJ Simons JF Simpson JW Srinivasan M Tartaro KR Tomasz A Vogt KA Volkmer GA Wang SH Wang Y Weiner MP 《Nature》2005,437(7057):376-380
The proliferation of large-scale DNA-sequencing projects in recent years has driven a search for alternative methods to reduce time and cost. Here we describe a scalable, highly parallel sequencing system with raw throughput significantly greater than that of state-of-the-art capillary electrophoresis instruments. The apparatus uses a novel fibre-optic slide of individual wells and is able to sequence 25 million bases, at 99% or better accuracy, in one four-hour run. To achieve an approximately 100-fold increase in throughput over current Sanger sequencing technology, we have developed an emulsion method for DNA amplification and an instrument for sequencing by synthesis using a pyrosequencing protocol optimized for solid support and picolitre-scale volumes. Here we show the utility, throughput, accuracy and robustness of this system by shotgun sequencing and de novo assembly of the Mycoplasma genitalium genome with 96% coverage at 99.96% accuracy in one run of the machine. 相似文献
374.
Recognition of unmethylated histone H3 lysine 4 links BHC80 to LSD1-mediated gene repression 总被引:1,自引:0,他引:1
Lan F Collins RE De Cegli R Alpatov R Horton JR Shi X Gozani O Cheng X Shi Y 《Nature》2007,448(7154):718-722
375.
ABSTRACT New Baltic amber species of Pteromalidae sensu lato are described, from two different subfamilies, Asaphesinae n. n. and Eunotinae. Asaphesinae is provided as a replacement name for Asaphinae Ashmead 1904, which is a junior homonym of the trilobite family Asaphidae Burmeister 1843. Coriotela lasallei gen. n., sp. n.. and Butiokeras costae gen. n., sp. n.. are described as the first known fossil species of Asaphesinae and Eunotinae, respectively. These species establish the minimum known age of both groups in the Eocene. Taxonomic changes are also proposed for some extant species. The genus Desantisiana Neder de Román syn. n.. is found to be a junior synonym of Notoglyptus, and its only described species is transferred as Notoglyptus jujuyensis (Neder de Román) comb. n.. The tribe Calyconotiscini, previously classified in Eunotinae, is abolished and Calyconotiscus Narendran & Saleem is transferred to Pireninae. http://www.zoobank.org/urn:lsid:zoobank.org:pub:7A107FF9-28E7-40AA-8A9B-71321E476C07 相似文献
376.
John Law 《Systemic Practice and Action Research》1992,5(4):379-393
This paper describes the theory of the actor-network, a body of theoretical and empirical writing which treats social relations, including power and organization, as network effects. The theory is distinctive because it insists that networks are materially heterogeneous and argues that society and organization would not exist if they were simply social. Agents, texts, devices, architectures are all generated in, form part of, and are essential to, the networks of the social. And in the first instance, all should be analyzed in the same terms. Accordingly, in this view, the task of sociology is to characterize the ways in which materials join together to generate themselves and reproduce institutional and organizational patterns in the networks of the social. 相似文献
377.
The mas oncogene encodes an angiotensin receptor 总被引:24,自引:0,他引:24
The class of receptors coupled to GTP-binding proteins share a conserved structural motif which is described as a 'seven-transmembrane segment' following the prediction that these hydrophobic segments form membrane-spanning alpha-helices. Identified examples include the mammalian opsins, alpha 1-, alpha 2-, beta 1- and beta 2-adrenergic receptors, the muscarinic receptor family, the 5-HT1C-receptor, and the substance-K receptor. In addition, two mammalian genes have been identified that code for predicted gene products with sequence similarity to these receptors, but whose ligand specificity is unknown namely, G21 and the mas oncogene. The mas oncogene shows the greatest sequence similarity to the substance-K receptor, and on this basis it was predicted that it would encode a peptide receptor with mitogenic activity which would act through the inositol lipid signalling pathways. The mas oncogene product was transiently expressed in Xenopus oocytes, and stably expressed in a transfected mammalian cell line. The results demonstrate that the mas gene product is a functional angiotensin receptor. 相似文献
378.
379.
John B. Guerard 《Journal of forecasting》1989,8(3):315-329
It has been shown in recent economic and statistical studies that composite forecasts may produce more accurate forecasts than individual ones. The purpose of this study is to develop composite forecasting models that may produce forecasts superior to the individual forecast implicit in forward exchange rates. In an efficient market one would expect to find little improvement with the composite models relative to the forward exchange rate. 相似文献
380.
This paper evaluates a general, infinite family of clustering algorithms, called the Lance and Williams algorithms, with respect to the space-conserving criterion. An admissible clustering criterion is defined using the space conserving idea. Necessary and sufficient conditions for Lance and Williams clustering algorithms to satisfy space-conserving admissibility are provided. Space-dilating, space-contracting, and well-structured clustering algorithms are also discussed.The work of J. Van Ness was supported by NSF Grant #DMS 9201075. 相似文献