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961.
Jishan Fan Hongjun Gao Takayoshi Ogawa Futoshi Takahashi 《Mathematische Nachrichten》2012,285(16):1963-1968
We consider the regularity problem under the critical condition to the biharmonic map heat flow from ?4 to a smooth compact Riemannian manifold without boundary. Using Gagliardo‐Nirenberg inequalities and delicate estimates, the Serrin type regularity criterion for the smooth solutions of biharmonic map heat flow is obtained without assuming a smallness condition on the initial energy. Our result improved the results of Lamm in 5 and 6 and generalized the results of Chang, Wang, Yang 1 , Strzelecki 11 and Wang 13 , 14 to non‐stationary case. 相似文献
962.
F1‐ATPase is an adenosine tri‐phosphate (ATP)‐driven rotary motor enzyme. We investigated the structural fluctuations and concerted motions of subunits in F1‐ATPase using molecular dynamics (MD) simulations. An MD simulation for the α3β3γ complex was carried out for 30 ns. Although large fluctuations of the N‐terminal domain observed in simulations of the isolated βE subunit were suppressed in the complex simulation, the magnitude of fluctuations in the C‐terminal domain was clearly different among the three β subunits (βE, βTP, and βDP). Despite fairly similar conformations of the βTP and βDP subunits, the βDP subunit exhibits smaller fluctuations in the C‐terminal domain than the βTP subunit due to their dissimilar interface configurations. Compared with the βTP subunit, the βDP subunit stably interacts with both the adjacent αDP and αE subunits. This sandwiched configuration in the βDP subunit leads to strongly correlated motions between the βDP and adjacent α subunits. The βDP subunit exhibits an extensive network of highly correlated motions with bound ATP and the γ subunit, as well as with the adjacent α subunits, suggesting that the structural changes occurring in the catalytically active βDP subunit can effectively induce movements of the γ subunit. © 2010 Wiley Periodicals, Inc. J Comput Chem 2010 相似文献
963.
Starting from trimethylsilyl enol ether of 1-acetyl-1,3,5-cycloheptatriene, the title 1,1-dimethyl-, 1,1-diethyl-, and 1,1-dipropyl-1H-azulenium cations 6-8 were synthesized in five steps. The order of pKR+ values of these cations was found to be 7>8>6. A comparison of the values between 1,1-dialkyl- and 1,1-spiroalkylated 1H-azulenium cations with the same number of carbon atoms at the 1-position provided the results of 7>1 and 8<3. The cation 8 shows a relatively lower pKR+ value to those of 3 and 7 probably due to its slightly bulkier propyl groups from which solvation stabilization of 8 under the conditions suffers. An intermolecular charge-transfer interaction between the cations and dibenzo-24-crown-8 was also studied. 相似文献
964.
Summary The isoforms of a fish galectin, congerins I and II, have several features that make them suitable for a study of accelerated process of molecular diversification based on 3D structures: They have been generated by a gene duplication, and still maintain 47% amino acid sequence identity to each other. Their genes show very high K
A/K
S ratio, and are though to be components of fish defense system. The crystal systems for a high-resolution analysis are known for both proteins. A series of works with biochemistry, molecular biology, and X-ray crystallography techniques have suggested that the two proteins might have evolved under differential selection pressures. Congerin I appeared to be a stabilized version of galectin-1. Congerin II was shown to be adapted to a new carbohydrate-ligand. The 3D structures of the wild type and mutant proteins have revealed the probable cause and consequence of the selection pressure responsible for the diversification of congerins. 相似文献
965.
Tourniaire G Collins J Campbell S Mizomoto H Ogawa S Thaburet JF Bradley M 《Chemical communications (Cambridge, England)》2006,(20):2118-2120
Microarray screening of polymer libraries for cellular adhesion was developed utilising a thin film of agarose to allow unsurpassed localisation of cell binding onto the array substrate and the discovery of cell specific polymers. 相似文献
966.
Maeda T Nagafuchi N Kubota A Kadokami K Ogawa HI 《Journal of chromatographic science》2006,44(2):96-100
Two kinds of hydroxylamino-dinitrotoluenes (HADNTs), 2-hydroxylamino-4,6-dinitrotoluene (2HADNT) and 4-hydroxylamino-2,6-dinitrotoluene (4HADNT), are known to be major metabolites produced from 2,4,6-trinitrotoluene (TNT) by bacteria. These chemicals could not be identified as TNT metabolites produced by Pseudomonas sp. strain TM15 because the mass spectra of these chemicals could not be obtained by liquid chromatography-mass spectrometry (MS) or gas chromatography-MS, which are the classic methods for identifying the metabolites of xenobiotics. However, these problems are overcome by isolating 2HADNT and 4HADNT from TNT metabolites with one-step thin-layer chromatography using dichloromethane as the developing solvent, and individually extracting them into acetonitrile by collecting spots of 2HADNT and 4HADNT. The purity of each HADNT was approximately 98%, based on the results of high-performance liquid chromatographic analyses. 2HADNT and 4HADNT are identified by obtaining their mass spectra with laser time-of-flight MS. 2HADNT and 4HADNT dissolve in distilled water and are spontaneously broken down with time. Also, heat treatment (increasing temperatures) and dissolved oxygen accelerate the destruction of HADNTs. This technique may be applicable for the identification and exact quantitative analysis of unstable and fragile compounds such as HADNTs. 相似文献
967.
Araki T Enomoto S Furuno K Gando Y Ichimura K Ikeda H Inoue K Kishimoto Y Koga M Koseki Y Maeda T Mitsui T Motoki M Nakajima K Nakamura K Ogawa H Ogawa M Owada K Ricol JS Shimizu I Shirai J Suekane F Suzuki A Tada K Takeuchi S Tamae K Tsuda Y Watanabe H Busenitz J Classen T Djurcic Z Keefer G Leonard DS Piepke A Yakushev E Berger BE Chan YD Decowski MP Dwyer DA Freedman SJ Fujikawa BK Goldman J Gray F Heeger KM Hsu L Lesko KT Luk KB Murayama H O'Donnell T Poon AW Steiner HM Winslow LA 《Physical review letters》2006,96(10):101802
The Kamioka Liquid scintillator Anti-Neutrino Detector is used in a search for single neutron or two-neutron intranuclear disappearance that would produce holes in the -shell energy level of (12)C nuclei. Such holes could be created as a result of nucleon decay into invisible modes (inv), e.g., n--> 3v or nn--> 2v. The deexcitation of the corresponding daughter nucleus results in a sequence of space and time-correlated events observable in the liquid scintillator detector. We report on new limits for one- and two-neutron disappearance: tau(n--> inv) > 5.8 x 10(29) years and tau (nn--> inv) > 1.4 x 10(30) years at 90% C.L. These results represent an improvement of factors of approximately 3 and >10(4) and over previous experiments. 相似文献
968.
Takaki Kanbara Keisuke Okada Hiromitsu Ogawa 《Journal of organometallic chemistry》2004,689(10):1860-1864
Reaction of 1,3-bis(1-pyrrolidinothiocarbonyl)benzene with PtCl2(PhCN)2 afforded a platinum complex with η3-S,C,S type coordination. The molecular structure of the SCS-pincer platinum(II) complex was determined by X-ray analysis. Substitution of chloro ligand with anionic ligands such as iodo and acetylide was carried out. The complexes exhibit strong emission in a glassy frozen state as well as in the solid state. Light-emitting diodes based on the complexes displayed red electroluminescence. 相似文献
969.
A macroreticular polystyrene-based chelating resin with oxime and diethylamino functional groups has been synthesized. The resin is stable in acid and alkaline solutions; no decrease in nitrogen content or capacity for sorption of copper(II) is observed when it is exposed to 3M hydrochloric acid and 1M sodium hydroxide for 7 days. The resin has higher selectivity for copper(II) than for other metal ions tested and the time required for 50% uptake of copper(II) is 15 min. The highest capacity for copper(II) is 2.0 mmole/g at pH 6.0. In a column operation, quantitative recovery of copper(II) is achieved by elution with 1M hydrochloric acid, and the resin can be used repeatedly. 相似文献
970.
M.Muramatsu A.Kitagawa Y.Iwata K.Yamamoto H.Ogawa S.Hojo Y.Sakamoto T.Honma W.Takasugi M.Wakaisami Y.Yoshida T.Kubo Y.Kato S.Biri 《中国物理 C》2007,31(Z1):60-62
Four ECR ion sources have been operated in National Institute of Radiological Sciences(NIRS). Two ECR ion sources supply various ion species for the Heavy Ion Medical Accelerator in Chiba(HIMAC). The 10GHz NIRS-ECR ion source mainly produces C~(2 ) ions for the heavy-ion therapy.Ions of Si,Ar,Fe,Kr and Xe are usually produced by the 18GHz NIRS-HEC ion source for physical and biological experiments.The other two compact ECR ion sources with all permanent magnet configuration have been developed for the new generation carbon therapy facility.One of these,the Kei-source,is a prototype which has been installed to the NIRS-930 cyclotron for axial injection.The other source,Kei2-source,is a demonstration source and utilized for the new generation Linac.In addition,both Kei sources have been used to study fundamental properties. In this paper,present status of the ion sources and recent developments are reported. 相似文献