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101.
Glen B. Deacon Pauline Pearson Brian W. Skelton Leone Spiccia Allan H. White 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(12):m537-m539
The syntheses and crystal structure determinations of a pair of `sawhorse' dimers are reported, viz. [Ru2(C6H5CO2)2(C5H5N)2(CO)4] [a new polymorph, cf. Kepert, Deacon, Spiccia, Fallon, Skelton & White (2000). J. Chem. Soc. Dalton Trans. pp. 2867–2874] and [Ru2(CF3CO2)2(C5H5N)2(CO)4]. The Ru⋯Ru distances are 2.6724 (2) and 2.7122 (5) Å, respectively. 相似文献
102.
Saki Tanaka Yusuke Nakaya Kazufumi Ninomiya Hironori Nishio Junichi Onishi Robert Openshaw Matthew Pearson Yumi Totsuka Jiro Murata 《Physics of Particles and Nuclei》2014,45(1):237-240
A new experiment named MTV-G, probing a large electron spin-precession due to a possible strong gravitational field, which predicted by large extra dimension model, is started at TRIUMF from 2011. In an electron-nuclear scattering experiment, a strong gravitational field is tested as a large spin precession effect caused by geodetic precession predicted by general relativity theory as a result of a warped space-time around nuclei. Experimental design using spin polarized electron source and Mott-spin analyzer, commissioning experiment and the preliminary results are described. 相似文献
103.
We report an NMR experimental realization of a rapid quantum deletion algorithm that deletes marked states in an unsorted database.Unlike classical deletion,where search and deletion are equivalent,quantum deletion can be implemented with only a single query,which achieves exponential speed-up compared to the optimal classical analog.In the experimental realization,the GRAPE algorithm was used to obtain an optimized NMR pulse sequence,and the efficient method of maximum-likelihood has been used to reconstruct the experimental output state. 相似文献
104.
Meredith J Layton Mirette Saad Nicole L Church Richard B Pearson Christina A Mitchell Wayne A Phillips 《BMC biochemistry》2012,13(1):1-9
Background
Hyaluronan (HA) is made at the plasma membrane and secreted into the extracellular medium or matrix by phospolipid-dependent hyaluronan synthase (HAS), which is active as a monomer. Since the mechanism by which HA is translocated across membranes is still unresolved, we assessed the presence of an intraprotein pore within HAS by adding purified Streptococcus equisimilis HAS (SeHAS) to liposomes preloaded with the fluorophore Cascade Blue (CB).Results
CB translocation (efflux) was not observed with mock-purified material from empty vector control E. coli membranes, but was induced by SeHAS, purified from membranes, in a time- and dose-dependent manner. CB efflux was eliminated or greatly reduced when purified SeHAS was first treated under conditions that inhibit enzyme activity: heating, oxidization or cysteine modification with N-ethylmaleimide. Reduced CB efflux also occurred with SeHAS K48E or K48F mutants, in which alteration of K48 within membrane domain 2 causes decreased activity and HA product size. The above results used liposomes containing bovine cardiolipin (BCL). An earlier study testing many synthetic lipids found that the best activating lipid for SeHAS is tetraoleoyl cardiolipin (TO-CL) and that, in contrast, tetramyristoyl cardiolipin (TM-CL) is an inactivating lipid (Weigel et al, J. Biol. Chem. 281, 36542, 2006). Consistent with the effects of these CL species on SeHAS activity, CB efflux was more than 2-fold greater in liposomes made with TO-CL compared to TM-CL.Conclusions
The results indicate the presence of an intraprotein pore in HAS and support a model in which HA is translocated to the exterior by HAS itself. 相似文献105.
Polymeric versions of deacetylated auranofin, a gold complex with a sugar ligand, were prepared by post-modifying RAFT glycopolymers. Micellisation of a block copolymer containing pendant Au(I) units produced nanoparticles with an increased anti-proliferative effect against OVCAR-3 human ovarian carcinoma cells. 相似文献
106.
107.
108.
We present necessary and sufficient conditions for a critical point of certain two-dimensional cubic differential systems to be a centre. Extensive use of the computer algebra system REDUCE is involved. The search for necessary and sufficient conditions for a centre has long been of considerable interest in the theory of nonlinear differential equations. It has proved to be a difficult problem, and full conditions are known for very few classes of systems. Such conditions are also required in the investigation of Hilbert's sixteenth problem concerning the number of limit cycles of polynomial systems. 相似文献
109.
110.
We derive Feynman rules for gauge theories exhibiting spontaneous symmetry breaking using the real-time formalism of finite temperature field theory. We also derive the thermal propagators where only the physical degrees of freedom are given thermal boundary conditions. We analyse the abelian Higgs model and find that these new propagators simplify the calculation of the thermal contribution to the self energy. 相似文献