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91.
The mammalian tongue is one of the most important organs during food uptake because it is helpful for mastication and swallowing.
In addition, taste receptors are present on the surface of the tongue. Lipids are the second most abundant biomolecules after
water in the tongue. Lipids such as phosphatidylcholine (PC), lysophosphatidylcholine (LPC) and sphingomyelin (SM) are considered
to play fundamental roles in the mediation of cell signaling. Imaging mass spectrometry (IMS) is powerful tool for determining
and visualizing the distribution of lipids across sections of dissected tissue. In this study, we identified and visualized
the PC, LPC, and SM species in a mouse tongue body section with matrix-assisted laser desorption/ionization (MALDI)-IMS. The
ion image constructed from the peaks revealed that docosahexaenoic acid (DHA)-containing PC, LPC, linoleic acid-containing
PC and SM (d18:1/16:0), and oleic acid-containing PC were mainly distributed in muscle, connective tissue, stratified epithelium,
and the peripheral nerve, respectively. Furthermore, the distribution of SM (d18:1/16:0) corresponded to the distribution
of nerve tissue relating to taste in the stratified epithelium. This study represents the first visualization of PC, LPC and
SM localization in the mouse tongue body. 相似文献
92.
Ishida Y Shimada T Masui D Tachibana H Inoue H Takagi S 《Journal of the American Chemical Society》2011,133(36):14280-14286
The quantitative excited energy transfer reaction between cationic porphyrins on an anionic clay surface was successfully achieved. The efficiency reached up to ca. 100% owing to the "Size-Matching Rule" as described in the text. It was revealed that the important factors for the efficient energy transfer reaction are (i) suppression of the self-quenching between adjacent dyes, and (ii) suppression of the segregated adsorption structure of two kinds of dyes on the clay surface. By examining many different kinds of porphyrins, we found that tetrakis(1-methylpyridinium-3-yl) porphyrin (m-TMPyP) and tetrakis(1-methylpyridinium-4-yl) porphyrin (p-TMPyP) are the suitable porphyrins to accomplish a quantitative energy transfer reaction. These findings indicate that the clay/porphyrin complexes are promising and prospective candidates to be used for construction of an efficient artificial light-harvesting system. 相似文献
93.
Coronene (C(24)H(12)) is a flat polyaromatic hydrocarbon consisting of seven peri-fused benzene rings and attracts lots of attention as a fragment of graphene. Using a hybrid method of quantum chemistry and statistical mechanics called RISM-SCF, which is an alternative to QM/MM, the electronic structure and solvation structure of a coronene-transition metal complex were computed in a self-consistent manner. The binding of a ruthenium complex ([C(5)H(5)Ru](+)) was extensively studied, especially the changing of the solvation structure. 相似文献
94.
Hirofumi Minamoto Robert Seifried Peter Eberhard Shozo Kawamura 《European Journal of Mechanics - A/Solids》2011,30(3):336-344
In machine dynamics impacts are usually common phenomena, resulting from collisions of moving bodies. Even low velocity impacts might produce high stresses in the contact region, which result in inelastic deformation. Thereby, visco-plastic materials, such as steel, show a significant increase of the yield stress with the strain rate. In machine dynamics repeated collisions occur, resulting in repeated impacts on a previously deformed contact area. Then, inelastic deformation and the resulting residual stresses produced by previous impacts have an influence on the behavior of the following impacts. Thus, the impact behavior varies with the number of impacts. This paper presents a numerical and experimental evaluation of repeated impacts with identical impact velocity up to 3 m/s, whereby the deformation history of the contact area, due to previous impacts, is included. The approach is applied to longitudinal impacts of an elastic steel sphere on a steel rod with distinct visco-plastic material behavior which is identified by Split Hopkinson Pressure Bar tests. A Finite Element analysis and experimental verification using two Laser-Doppler-Vibrometers are performed. It is shown that for an accurate impact simulation the FE model must include the visco-plastic material behavior of the steel. Further it is found that the maximal contact force, the rebound velocity and the coefficient of restitution increase with the number of impacts, while the contact duration decreases with the number of impacts. After several impacts these quantities show saturation to a constant value, indicating no significant additional inelastic deformation in the later impacts. Further, the residual stress distribution, the maximal von Mises stress distribution and the local deformation at the contact point are evaluated and a characteristic force-deformation diagram is obtained. Finally, an analysis is performed to describe the relation between maximal force and remaining crater at the contact point. 相似文献
95.
Hirofumi Ishikawa Yuta Nagasaka Hitoshi Ohta Takao Nanba Ryouji Kanno 《Journal of Physics and Chemistry of Solids》2005,66(11):2065-2067
The reflection measurements of superionic conductors LiCoO2 and Li1-xCoO2, which are already in use for the positive electrode material of 4 V rechargeable lithium batteries, have been performed in the millimeter wave region from 6 to 60 cm−1 using the electron storage ring facilities of Institute of Molecular Science in Okazaki. The increase of the reflectivity has been observed in the low wavenumber region below 10 cm-1 above 300 K in Li1-xCoO2 for the first time, while the reflectivity of LiCoO2 has almost the constant value in all observed temperature region between 77 to 380 K. The results will be discussed in connection with our previous results of LiNiO2. 相似文献
96.
97.
Nobutoshi Kiba Youhei Inoue Masaki Tachibana Kazue Tani Hitoshi Koizumi 《Analytical sciences》2003,19(8):1203-1206
A chemiluminometric flow-through sensor for the simultaneous determination of glucose (Glu) and 3-hydroxybutyrate (HB) in a single sample has been developed. Coimmobilized 3-hydroxybutyrate dehydrogenase/NADH oxidase/peroxidase, a support material, and coimmobilized glucose dehydrogenase/NADH oxidase/peroxidase were packed sequentially in a transparent PTFE tube. The tube was then placed in front of a photomultiplier tube as a flow cell. A two-peak recording was obtained by one injection of the sample solution. The peak heights of the first and second peaks were dependent on the concentrations of HB and Glu, respectively. The calibration graphs for HB and Glu were linear at 0.05-10 and 0.1-30 microM, respectively. The maximum sample throughput was 30 h(-1). The sensor was stable for two weeks. 相似文献
98.
Efficient optical phase-conjugate (PC) signals in four kinds of novel polyester films containing cyanoazobenzene units in the side chain are reported. One of them can efficiently generate only the photoinduced anisotropy (PA) component of PC signal, while the other three films can simultaneously generate two types of PC signals, PA and holographic components. These polymers have good potential not only as a phase conjugator but also as a polarization-sensitive hologram-recording material.Presented at the International Commission for Optics Topical Meeting, Kyoto, 1994 相似文献
99.
Hirofumi Osada 《Communications in Mathematical Physics》1996,176(1):117-131
We construct infinite-dimensional Wiener processes with interactions by constructing specific quasi-regular Dirichlet forms. Our assumptions are very mild; accordingly, our results can be applied to singular interactions such as hard core potentials, Lennard-Jones type potentials, and Dyson's model. We construct nonequilibrium dynamics.Dedicated to Professor Masatoshi Fukushima on his 60th birthday 相似文献
100.
Cationic liposomes enhanced firefly bioluminescent assay of bacterial ATP in the presence of an ATP extractant. 总被引:1,自引:0,他引:1
Naohiro Nakata Akihiko Ishida Hirofumi Tani Tamio Kamidate 《Analytical sciences》2003,19(8):1183-1185
Cationic liposomes composed of two components, diethylaminoethyl-carbamoyl cholesterol and phosphatidylcholine, were applied to an enhancer for a firefly bioluminescent (BL) assay of bacterial ATP in the presence of an ATP extractant. Trichloroacetic acid (TCA), which inhibits the activity of luciferase, was used as an ATP extractant. Cationic liposomes enhanced the BL intensity as long as luciferase was active. The detection limits for cell numbers of Escherichia coli extracts in the presence of cationic liposomes and in water alone were 199 and 897 colony forming units ml(-1), respectively. The sensitivity for bacterial ATP in the presence of cationic liposomes was improved by a factor of 2.5 times compared to that in the presence of diethylaminoethyl-dextran. 相似文献