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1.
Yuta Yamamoto Shogo Nakano Fumio Seki Yasuteru Shigeta Sohei Ito Hiroaki Tokiwa Makoto Takeda 《Molecules (Basel, Switzerland)》2021,26(5)
Infection of hosts by morbilliviruses is facilitated by the interaction between viral hemagglutinin (H-protein) and the signaling lymphocytic activation molecule (SLAM). Recently, the functional importance of the n-terminal region of human SLAM as a measles virus receptor was demonstrated. However, the functional roles of this region in the infection process by other morbilliviruses and host range determination remain unknown, partly because this region is highly flexible, which has hampered accurate structure determination of this region by X-ray crystallography. In this study, we analyzed the interaction between the H-protein from canine distemper virus (CDV-H) and SLAMs by a computational chemistry approach. Molecular dynamics simulations and fragment molecular orbital analysis demonstrated that the unique His28 in the N-terminal region of SLAM from Macaca is a key determinant that enables the formation of a stable interaction with CDV-H, providing a basis for CDV infection in Macaca. The computational chemistry approach presented should enable the determination of molecular interactions involving regions of proteins that are difficult to predict from crystal structures because of their high flexibility. 相似文献
2.
3.
Yasuyuki Agari Kiyofumi Sakai Yosikazu Kano Ryoki Nomura 《Journal of Polymer Science.Polymer Physics》2007,45(21):2972-2981
We prepared biodegradable poly(ethylene oxide) (PEO)/poly(L ‐lactic acid) (PLLA) graded blends by the dissolution–diffusion process, and discussed the biodegradability and tensile strength of the graded blends by comparing isotropic blend and PLLA only. All the graded blends were degraded more largely than the PLLA only and isotropic blend (PEO: 37.5 wt %), which had the same content as the total content of those graded blends. The graded blend having most excellent wide compositional gradient was degraded most largely with the enzyme. Thus, graded structure of the blends promoted their biodegradabilities large. It was considered that the dissolution of PEO with water increased the surface area attacked by the enzyme, while PEO caught PLLA oligomers to promote the biodegradation of PLLA. Then, the biodegradabilities of the graded blends were suppressed by the increasing crystallinity of PLLA. Furthermore, the strengths of all the graded blends were larger than those of the isotropic blend. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 2972–2981, 2007 相似文献
4.
Akira Yanagisawa Prof. Dr. Takahiro Suzuki Takanori Koide Shogo Okitsu Takayoshi Arai Prof. Dr. 《化学:亚洲杂志》2008,3(10):1793-1800
A Barbier‐type regioselective propargylation of aldehydes and ketones with (3‐bromobut‐1‐ynyl)trimethylsilane has been achieved using reactive barium as a low‐valent metal in THF. Especially in the case of ketones, the corresponding homopropargylic alcohols form almost exclusively. In the reaction of α,β‐unsaturated carbonyl compounds, only 1,2‐adducts have been observed. This method is also applicable to propargylation of imines, and the corresponding homopropargylic amines are obtained regiospecifically in good yields with diastereomeric ratios of up to 87:13. 相似文献
5.
Let Cld
AW
(X) be the hyperspace of nonempty closed subsets of a normed linear space X with the Attouch–Wets topology. It is shown that the space Cld
AW
(X) and its various subspaces are AR's. Moreover, if X is an infinite-dimensional Banach space with weight w(X) then Cld
AW
(X) is homeomorphic to a Hilbert space with weight 2
w(X). 相似文献
6.
7.
8.
Selective oxidation of an AlInAs layer was investigated for enhancement of magneto-optic effect in an optical isolator. Twelve times nonreciprocal phase shift enhancement was estimated from a measured AlInAs-oxide refractive index. 相似文献
9.
Teruhisa Horita Katsuhiko Yamaji Natsuko Sakai Yueping Xiong Harumi Yokokawa Tatsuya Kawada 《Ionics》2002,8(1-2):108-117
The oxygen reduction active sites were visualized around the O2/SOFC cathode/electrolyte triple phase boundaries (TPB) by the16O/18O exchange techniques and secondary ion mass spectrometry (SIMS) analysis. The higher18O concentration is observed on the cathode top surfaces (La0.9Sr0.1MnO3-mesh, Au-mesh, and Ag-porous), which suggested the promotion of oxygen adsorption and oxygen surface exchange at the cathode.
The oxygen diffusion through the bulk of cathode occurred at the La0.9Sr0.1MnO3-mesh and the Ag-porous cathodes, not at the Au-mesh cathode. On the YSZ surfaces after removing the cathode, the active sites
for oxygen incorporation were analyzed by SIMS. The active sites for oxygen incorporation were at the La0.9Sr0.1MnO3/YSZ interface as well as the TPB. On the other hand, the active sites for oxygen incorporation are limited to the TPB in
the case of the Au-mesh removed YSZ surface. From the SIMS analysis, the expansion of the active sites for oxygen incorporation
is less than a few μm from the TPB lines.
Paper presented at the 8th EuroConference on Ionics, Carvoeiro, Algarve, Portugal, Sept. 16–22, 2001. 相似文献
10.
P. Periasamy K. Tatsumi N. Kalaiselvi M. Shikano T. Fiyieda Y. Saito T. Sakai M. Mizukata A. Kajinami S. Deki 《Ionics》2002,8(5-6):453-460
A series of gel polymer electrolytes containing PVdF as homo polymer, a mixture of 1:1 Ethylene Carbonate (EC) : Propylene
Carbonate (PC) as plasticizer and lithium-bistrifluoromethane sulphone imide [imide — LiN (CF3SO2)2] has been developed. Amounts of polymer (PVdF), plasticizer and the imide lithium salt have been varied as a function of
their weight ratio composition in this regard. Dimensionally stable films possessing appreciable room temperature conductivity
values have been obtained with respect to certain weight ratio compositions. However, conductivity data have been recorded
at different possible temperatures, i.e., from 20 °C to 65 °C. XRD and DSC studies were carried out to characterize the polymer
films for better amorphicity and reduced glass transition temperature, respectively. The electrochemical interface stability
of the PVdF based gel polymer electrolytes over a range of storage period (24 h – 10 days) have been investigated using A.C.
impedance studies. Test cells containing Li/gel polymer electrolyte (GPE)/Li have been subjected to undergo 50 charge-discharge
cycles in order to understand the electrochemical performance behaviour of the dimensionally stable films of superior conductivity.
The observed capacity fade of less than 20% even after 50 cycles is in favour of the electrochemical stability of the gel
polymer electrolyte containing 27.5% PVdF −67.5 % EC+PC −5% imide salt. Cyclic voltammetry studies establish the possibility
of a reversible intercalation — deintercalation process involving Li+ ions through the gel polymer electrolyte. 相似文献