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排序方式: 共有268条查询结果,搜索用时 15 毫秒
91.
92.
Ahn C. Doherty A.C. Hayden P. Winter A.J. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2006,52(10):4349-4357
The problem of distributed compression for correlated quantum sources is considered. The classical version of this problem was solved by Slepian and Wolf, who showed that distributed compression could take full advantage of redundancy in the local sources created by the presence of correlations. Here it is shown that, in general, this is not the case for quantum sources, by proving a lower bound on the rate sum for irreducible sources of product states which is stronger than the one given by a naive application of Slepian-Wolf. Nonetheless, strategies taking advantage of correlation do exist for some special classes of quantum sources. For example, Devetak and Winter demonstrated the existence of such a strategy when one of the sources is classical. Optimal nontrivial strategies for a different extreme, sources of Bell states, are presented here. In addition, it is explained how distributed compression is connected to other problems in quantum information theory, including information-disturbance questions, entanglement distillation and quantum error correction 相似文献
93.
R.J. Beach M.D. Feit S.C. Mitchell K.P. Cutter S.A. Payne R.W. Mead J.S. Hayden D. Krashkevich D.A. Alunni 《Photonics Technology Letters, IEEE》2003,15(5):670-672
We report on the first experimental demonstration of a scalable fiber laser approach based on phase-locking multiple gain cores in an antiguided structure. A novel fabrication technology is used with soft glass components to construct the multiple core fiber used in our experiments. The waveguide region is rectangular in shape and comprised of a periodic sequence of gain and no-gain segments having nearly uniform refractive index. The rectangular waveguide is itself embedded in a lower refractive index cladding region. Experimental results confirm that our five-core Nd-doped glass prototype structure runs predominately in two spatial antiguided modes as predicted by our modeling. 相似文献
94.
N. G. Kozlenko V. V. Abaev V. S. Bekrenev S. P. Kruglov A. A. Koulbardis I. V. Lopatin A. B. Starostin B. Draper S. Hayden J. Huddleston D. Isenhower C. Robinson M. Sadler C. Allgower R. Cadman H. Spinka J. Comfort K. Craig A. Ramirez T. Kycia M. Clajus A. Marusic S. McDonald B. M. K. Nefkens N. Phaisangittisakul S. Prakhov J. W. Price W. B. Tippens J. Peterson W. J. Briscoe A. Shafi I. I. Strakovsky H. Staudenmaier D. M. Manley J. Olmsted D. Peaslee N. Knecht G. Lolos Z. Papandreou I. Supek I. Slaus A. Gibson D. Grosnic D. Koetke R. Manweiler S. Stanislaus 《Physics of Atomic Nuclei》2003,66(1):110-113
The first results obtained in 1998 by the Crystal Ball collaboration from a measurement of the total and differential cross sections for the reaction π ? p → ηn are presented. These new experimental results for the total cross sections are compared with the predictions of the K-matrix model for pion-nucleon scattering. The angular distribution at momenta near the reaction threshold (685 MeV/c) is determined by the S-wave contribution. The P-wave contribution begins to manifest itself from a momentum of 720 MeV/c. 相似文献
95.
The adsorption of NO on Ru(001), and its co-adsorption with oxygen, has been investigated using temperature programmed desorption and infra-red reflection-absorption spectroscopy (IRAS). Only one band due to the NO stretch of adsorbed NO could be observed and was assigned to the linearly bound v2 species. Pre-adsorption of oxygen caused surprisingly little effect on the total desorbed flux of NO and its dissociation products in the TPD spectrum. The main effect of oxygen was to shift intensity from the v1 peak to a new desorption peak v1(O), which is accompanied by a splitting in the IRAS spectrum of the v2 species. The absence of the band observed in the “bridging region” in EELS experiments and the small influence of the pre-adsorbed oxygen on the v2 species is discussed in the light of current models for this adsorption system. 相似文献
96.
Measurement of a radiative lifetime of 9.6 ± 1.0 nsec for the SiOA1Π-state is reported. RKR Franck-Condon factors have been computed and, with these, absolute oscillator strengths are calculated. A band system at ∼ 3022Å has been found that may be due to SiO+, but the band is not resolved at our experimental resolution, and identification remains uncertain. The upper state of the carrier of this spectrum has a radiative lifetime of 8.3 ± 0.8 nsec. 相似文献
97.
Inside Back Cover: Infinite Polyiodide Chains in the Pyrroloperylene–Iodine Complex: Insights into the Starch–Iodine and Perylene–Iodine Complexes (Angew. Chem. Int. Ed. 28/2016) 下载免费PDF全文
98.
Lipid nanotube formation from streptavidin-membrane binding 总被引:1,自引:0,他引:1
Liu H Bachand GD Kim H Hayden CC Abate EA Sasaki DY 《Langmuir : the ACS journal of surfaces and colloids》2008,24(8):3686-3689
A novel transformation of giant lipid vesicles to produce nanotubular structures was observed upon the binding of streptavidin to biotinylated membranes. Unlike membrane budding and tubulation processes caused by proteins involved with endocytosis and vesicle fusion, streptavidin is known to crystallize at near the isoelectric point (pI 5 to 6) into planar sheets against biotinylated films. We have found, however, that at neutral pH membranes of low bending rigidity (<10kT), such as 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), spontaneously produce tubular structures with widths ranging from micrometers to below the diffraction limit (<250 nm) and lengths spanning up to hundreds of micrometers. The nanotubes were typically held taut between surface-bound vesicles suggesting high membrane tension, yet the lipid nanotubes exhibited a fluidic nature that enabled the transport of entrained vesicles. Confocal microscopy confirmed the uniform coating of streptavidin over the vesicles and nanotubes. Giant vesicles composed of lipid membranes of higher bending energy exhibited only aggregation in the presence of streptavidin. Routes toward the development of these highly curved membrane structures are discussed in terms of general protein-membrane interactions. 相似文献
99.
Matthew G. Alteen Hayden Peacock Richard W. Meek Jil A. Busmann Sha Zhu Gideon J. Davies Hiroaki Suga David J. Vocadlo 《Angewandte Chemie (International ed. in English)》2023,62(5):e202215671
Glycosyltransferases are a superfamily of enzymes that are notoriously difficult to inhibit. Here we apply an mRNA display technology integrated with genetic code reprogramming, referred to as the RaPID (random non-standard peptides integrated discovery) system, to identify macrocyclic peptides with high binding affinities for O-GlcNAc transferase (OGT). These macrocycles inhibit OGT activity through an allosteric mechanism that is driven by their binding to the tetratricopeptide repeats of OGT. Saturation mutagenesis in a maturation screen using 39 amino acids, including 22 non-canonical residues, led to an improved unnatural macrocycle that is ≈40 times more potent than the parent compound (Kiapp=1.5 nM). Subsequent derivatization delivered a biotinylated derivative that enabled one-step affinity purification of OGT from complex samples. The high potency and novel mechanism of action of these OGT ligands should enable new approaches to elucidate the specificity and regulation of OGT. 相似文献
100.