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991.
Aoki T Hirano M Takeuchi Y Kobayashi T Yanagida T Ide T 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2010,86(9):920-925
Single channel currents of lysenin were measured using artificial lipid bilayers formed on a glass micropipette tip. The single channel conductance for KCl, NaCl, CaCl(2), and Trimethylammonium-Cl were 474 ± 87, 537 ± 66, 210 ± 14, and 274 ± 10 pS, respectively, while the permeability ratio P(Na)/P(Cl) was 5.8. By adding poly(deoxy adenine) or poly(L-lysine) to one side of the bilayer, channel currents were influenced when membrane voltages were applied to pass the charged molecules through the channel pores. Current inhibition process was concentration-dependent with applied DNA. As the current fluctuations of α-hemolysin channels is often cited as the detector in a molecular sensor, these results suggest that by monitoring channel current changes, the lysenin channel has possibilities to detect interactions between it and certain biomolecules by its current fluctuations. 相似文献
992.
We theoretically study the development of quantum turbulence from two counter-propagating superfluids of miscible Bose-Einstein condensates by numerically solving the coupled Gross-Pitaevskii equations. When the relative velocity exceeds a critical value, the countersuperflow becomes unstable and quantized vortices are nucleated, which leads to isotropic quantum turbulence consisting of two superflows. It is shown that the binary turbulence can be realized experimentally in a trapped system. 相似文献
993.
Daisuke Takeuchi Ryuichi Matsuura Kohtaro Osakada 《Macromolecular rapid communications》2008,29(24):1932-1936
Copolymerization of hepta‐1,6‐diene with ethylene using a cobalt–bis(imino)pyridine complex affords a polymer that contains trans‐1,2‐five‐membered rings in the repeating unit from hepta‐1,6‐diene. The ratio of the repeating units of diene to those of ethylene is controlled from 3: 97 to 50:50, depending on the reaction conditions. Isotope‐labeling reactions reveal that the major chain transfer pathway involves β‐hydrogen elimination of the polymer end formed after ethylene insertion.
994.
We found that the length of the Fermi arc decreases with increasing out-of-plane disorder by performing angle resolved photoemission spectroscopy (ARPES) measurements in the superconducting state of optimally doped R=La and Eu samples of Bi2Sr2−xRxCuOy. Since out-of-plane disorder stabilizes the antinodal pseudogap as was shown in our previous study of the normal state, the present results indicate that this antinodal pseudogap persists into the superconducting state and decreases the Fermi arc length. We think that the shrinkage of the Fermi arc reduces the superfluid density, which explains the large suppression of the superconducting transition temperature when out-of-plane disorder is increased. 相似文献
995.
A VHF H2 plasma was produced with the multi rod electrode at high pressure and the plasma parameters were measured as a function of pressure for different VHF powers at 60 MHz. It was found that when the pressure is increased, the ion saturation current peaks at certain pressure and finally decreases at high pressures, while the electron temperature is around 10 eV. The wall potential at high pressure was lower than the values estimated from the electron temperature using the probe theory. Furthermore, the anomalous reduction of the electron saturation current was observed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
996.
Ryuta Mizutani Akihisa Takeuchi Genta Akamatsu Kentaro Uesugi Yoshio Suzuki 《Journal of synchrotron radiation》2008,15(4):374-377
An application of X‐ray microtomography to the Drosophila adult brain stained with colloidal gold and a platinum compound is described. The transparency of biological tissue to hard X‐rays enables tomographic visualization of the three‐dimensional structure of tissue entrails. Each high‐Z element was visualized as a three‐dimensional structure from the difference absorption coefficient image at the corresponding LIII absorption edge. The cortex of the optic lobe was selectively visualized by the specific adsorption of colloidal gold. The entire structure revealed by the platinum impregnation allowed the anatomical assignment of the gold‐stained structures. Selective staining and specific visualization of biological tissues at micrometer resolution should elucidate the three‐dimensional cellular organization essential for the understanding and application of biological microstructures. 相似文献
997.
Ryuta Mizutani Akihisa Takeuchi Kentaro Uesugi Yoshio Suzuki 《Journal of synchrotron radiation》2008,15(6):648-654
A micro test pattern prepared by focused ion beam milling was used to evaluate the three‐dimensional resolution of a microtomograph at the BL20B2 beamline of SPring‐8. The resolutions along the direction within the tomographic slice plane and perpendicular to it were determined from the modulation transfer functions. The through‐plane resolution perpendicular to the tomographic slice was evaluated to be 8 µm, which corresponds to the spatial resolution of two‐dimensional radiographs. In contrast, the in‐plane resolution within the slice was evaluated to be 12 µm. Real‐space interpolation was performed prior to the tomographic reconstruction, giving an improved in‐plane resolution of 8.5 µm. However, the 8 µm pitch pattern was resolved in the interpolated slice image. To reflect this result, another resolution measure from the peak‐to‐valley difference plot was introduced. This resolution measure gave resolution limits of 7.4 µm for the in‐plane direction and 6.1 µm for the through‐plane direction. The three‐dimensional test pattern along with the interpolated reconstruction enables the quantitative evaluation of the spatial resolution of microtomographs. 相似文献
998.
Takashiro Akitsu Yuiri Takeuchi Yasuaki Einaga 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(11):o801-o802
The title compound, (RS)‐3,5‐dichloro‐2‐{[(1‐phenylethyl)imino]methyl}phenol, C15H13Cl2NO, was synthesized from racemic 1‐phenylethylamine and 3,5‐dichlorosalicylaldehyde. The π‐conjugate system around the imine group is essentially planar in the phenol–imine tautomer. Intramolecular O⋯N hydrogen‐bond and intermolecular C—H⋯π interactions are present in the crystal structure. 相似文献
999.
Kisho Mori Mitsuhiro Hirase Takahiro Morishige Eri Takano Hirobumi Sunayama Yukiya Kitayama Sachiko Inubushi Ryohei Sasaki Masakazu Yashiro Toshifumi Takeuchi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(6):1626-1629
Exosomes are small (30–100 nm) membrane vesicles that serve as regulatory agents for intercellular communication in cancers. Currently, exosomes are detected by immuno‐based assays with appropriate pretreatments like ultracentrifugation and are time consuming (>12 h). We present a novel pretreatment‐free fluorescence‐based sensing platform for intact exosomes, wherein exchangeable antibodies and fluorescent reporter molecules were aligned inside exosome‐binding cavities. Such antibody‐containing fluorescent reporter‐grafted nanocavities were prepared on a substrate by well‐designed molecular imprinting and post‐imprinting modifications to introduce antibodies and fluorescent reporter molecules only inside the binding nanocavities, enabling sufficiently high sensitivity to detect intact exosomes without pretreatment. The effectiveness of the system was demonstrated by using it to discriminate between normal exosomes and those originating from prostate cancer and analyze exosomes in tear drops. 相似文献
1000.
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