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131.
JH Cate AR Gooding E Podell K Zhou BL Golden AA Szewczak CE Kundrot TR Cech JA Doudna 《Canadian Metallurgical Quarterly》1996,273(5282):1696-1699
The crystal structure of a group I intron domain reveals an unexpected motif that mediates both intra- and intermolecular interactions. At three separate locations in the 160-nucleotide domain, adjacent adenosines in the sequence lie side-by-side and form a pseudo-base pair within a helix. This adenosine platform opens the minor groove for base stacking or base pairing with nucleotides from a noncontiguous RNA strand. The platform motif has a distinctive chemical modification signature that may enable its detection in other structured RNAs. The ability of this motif to facilitate higher order folding provides one explanation for the abundance of adenosine residues in internal loops of many RNAs. 相似文献
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Yang Y Hwang Y Cho HA Song JH Park SJ Rogers JA Ko HC 《Small (Weinheim an der Bergstrasse, Germany)》2011,7(4):484-491
The ability to create and manipulate large arrays of inorganic semiconductor micro/nanostructures for integration on unconventional substrates provides new possibilities in device engineering. Here, simple methods are described for the preparation of structures of single crystalline silicon in suspended and tethered configurations that facilitate their deterministic assembly using transfer-printing techniques. Diverse shapes (e.g., straight or curved edges), thicknesses (between 55 nm and 3 μm), and sizes (areas of 4000 μm(2) to 117 mm(2) ) of structures in varied layouts (regular or irregular arrays, with dense or sparse coverages) can be achieved, using either flat or cylindrical roller-type stamps. To demonstrate the technique, printing with 100% yield onto curved, rigid supports of glass and ceramics and onto thin sheets of plastic is shown. The fabrication of a printed array of silicon p(+) -i-n(+) junction photodiodes on plastic is representative of device-printing capabilities. 相似文献
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P. Messina E. Felten P. Hipes R. Williams A. Alagar A. Kamrath R. Leary W. Pfeiffer J. Rogers D. Walker 《Concurrency and Computation》1990,2(3):195-255
Recently, a number of advanced architecture machines have become commercially available. These new machines promise better cost performance than traditional computers, and some of them have the potential of competing with current supercomputers, such as the CRAY X-MP, in terms of maximum performance. This paper describes the methodology and results of a pilot study of the performance of a broad range of advanced architecture computers using a number of complete scientific application programs. The computers evaluated include:
- 1 shared-memory bus architecture machines such as the Alliant FX/8, the Encore Multimax, and the Sequent Balance and Symmetry
- 2 shared-memory network-connected machines such as the Butterfly
- 3 distributed-memory machines such as the NCUBE, Intel and Jet Propulsion Laboratory (JPL)/Caltech hypercubes
- 4 very long instruction word machines such as the Cydrome Cydra-5
- 5 SIMD machines such as the Connection Machine
- 6 ‘traditional’ supercomputers such as the CRAY X-MP, CRAY-2 and SCS-40.
138.
Boudellioua Mohamed S. Galkowski Krzysztof Rogers Eric 《Multidimensional Systems and Signal Processing》2019,30(4):2185-2197
Multidimensional Systems and Signal Processing - This paper considers a class of spatially interconnected systems formed by ladder circuits using two-dimensional systems theory. The individual... 相似文献
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