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51.
Yoshimune Nonomura Taku Miura Takaaki Miyashita Yuka Asao Hirokazu Shirado Yasutoshi Makino Takashi Maeno 《Journal of the Royal Society Interface》2012,9(71):1216-1223
Water detection is one of the most crucial psychological processes for many animals. However, nobody knows the perception mechanism of water through our tactile sense. In the present study, we found that a characteristic frictional stimulus with large acceleration is one of the cues to differentiate water from water contaminated with thickener. When subjects applied small amounts of water to a glass plate, strong stick-slip phenomena with a friction force of 0.46 ± 0.30 N and a vertical force of 0.57 ± 0.36 N were observed at the skin surface, as shown in previous studies. Surprisingly, periodic shears with acceleration seven times greater than gravitational acceleration occurred during the application process. Finite-element analyses predicted that these strong stimuli could activate tactile receptors: Meissner''s corpuscle and Pacinians. When such stimuli were applied to the fingertips by an ultrasonic vibrator, a water-like tactile texture was perceived by some subjects, even though no liquid was present between the fingertip and the vibrator surface. These findings could potentially be applied in the following areas: materials science, information technology, medical treatment and entertainment. 相似文献
52.
Zhenhua He Hirokazu Katsui Rong Tu Jianfeng Zhang Takashi Goto 《Journal of the American Ceramic Society》2014,97(3):681-683
SiC powder was coated with SiO2 layer by chemical vapor deposition, and the SiC(core)/SiO2(shell) composite powder was consolidated to a SiC/SiO2 composite with a mosaic microstructure by spark plasma sintering (SPS) at 1923 K for 1.8 ks. The SiC(core)/SiO2(shell) powder with a 80–100 nm thick SiO2 layer resulted in a SiC/SiO2 composite with a relative density of 97% and hardness and fracture toughness of 17.1 GPa and 8.4 MPa m1/2, respectively. 相似文献
53.
Release of short and proline-rich antihypertensive peptides from casein hydrolysate with an Aspergillus oryzae protease 总被引:4,自引:0,他引:4
Angiotensin-I converting enzyme inhibitory activities were measured after hydrolysis of casein by 9 different commercially available proteolytic enzymes. Among these enzymes, a protease isolated from Aspergillus oryzae showed the highest angiotensin-I converting enzyme inhibitory activity per peptide. The A. oryzae peptide also showed the highest antihypertensive effect in spontaneously hypertensive rats when the systolic blood pressure was measured 5 h after oral administration of 32 mg/kg of various enzymatic hydrolysates. Significant antihypertensive effects were observed with dosages of 9.6, 32, and 96 mg of the A. oryzae peptide/kg of body weight (BW), and the effects were dependent on these peptide dosages.Analysis of peptide length showed the A. oryzae hydrolysate was the shortest of all tested casein hydrolysates; the peptide mixture had an average value of 1.4 amino acids (AA) in the sequence. To further characterize the A. oryzae hydrolysate, we analyzed the AA sequence of the whole peptide mixture. Various AA were detected at the first AA position, however, an increased number of Pro residues were observed at the second and third position of the A. oryzae hydrolysate. No strong signals were detected after the fourth AA position of the A. oryzae hydrolysate. These results suggest that the casein hydrolysate of A. oryzae, which expressed potent antihypertensive effects in spontaneously hypertensive rats, mainly contain short peptides of X-Pro and X-Pro-Pro sequences. 相似文献
54.
High thermal conductivity of spark plasma sintered silicon carbide ceramics with yttria and scandia 下载免费PDF全文
Yu‐Kwang Seo Young‐Wook Kim Toshiyuki Nishimura Won‐Seon Seo 《Journal of the American Ceramic Society》2017,100(4):1290-1294
A fully dense SiC ceramic with a room‐temperature thermal conductivity of 262 W·(m·K)?1 was obtained via spark plasma sintering β‐SiC powder containing 0.79 vol% Y2O3‐Sc2O3. High‐resolution transmission electron microscopy revealed two different SiC‐SiC boundaries, that is, amorphous and clean boundaries, in addition to a fully crystallized junction phase. A high thermal conductivity was attributed to a low lattice oxygen content and the presence of clean SiC‐SiC boundaries. 相似文献
55.
Gel permeation chromatography of polyoxymethylene has been studied using N,N-dimethylformamide as the solvent. Polyoxymethylene samples used here are a copolymer of tetraoxane with 1,3-dioxolane and a commercial polyoxymethylene whose molecular weight distributions are moderately broad. Their intrinsic viscosities [η] range from 1.4 to 2.8 dl/g. Factors affecting chromatograms are discussed, and the operating conditions were determined by using the analytical scale GPC. On the basis of these operating conditions, the molecular weight fractionation of polyoxymethylene was carried out by using the preparative scale GPC. It was found that polyoxymethylene can be effectively fractionated to give seven to ten fractions each of them containing the fractionated polymer ranging in weight from 0.2 to 8 mg when 40 mg polymer sample was used for a run of the measurement. The fractionated polymers were also found to have a narrow molecular weight distribution within a single peak, and their Mw/Mn values decrease with increasing molecular weight. 相似文献
56.
Xin Xu Toshiyuki Nishimura Qing Huang Rong-Jun Xie Naoto Hirosaki Hidehiko Tanaka 《Journal of the American Ceramic Society》2007,90(12):4047-4049
A feasible doping strategy is introduced to synthesize Eu2+ -doped α-Si3 N4 nanowires coated with a thin BN film. The nanowires were characterized by X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and a fluorescence spectrophotometer. The Eu2+ -doped α-Si3 N4 nanowires emitted strong yellow light, which is related to the 4 f 6 5 d –4 f 7 transition of Eu2+ , upon a broad excitation wavelength range between 250 and 450 nm. The obtained nanowires provided a potential candidate for application in optical nanodevices, as well as in white LEDs. 相似文献
57.
Shuqi Guo Yutaka Kagawa Toshiyuki Nishimura Hidehiko Tanaka 《Journal of the American Ceramic Society》2007,90(7):2255-2258
The thermal and electrical properties of MoSi2 and/or SiC-containing ZrB2 -based composites and the effects of MoSi2 and SiC contents were examined in hot-pressed ZrB2 –MoSi2 –SiC composites. The thermal conductivity and electrical conductivity of the ZrB2 –MoSi2 –SiC composites were measured at room temperature by a nanoflash technique and a current–voltage method, respectively. The results indicate that the thermal and electrical conductivities of ZrB2 –MoSi2 –SiC composites are dependent on the amount of MoSi2 and SiC. The thermal conductivities observed for all of the compositions were more than 75 W·(m·K)−1 . A maximum conductivity of 97.55 W·(m·K)−1 was measured for the 20 vol% MoSi2 -30 vol% SiC-containing ZrB2 composite. On the other hand, the electrical conductivities observed for all of the compositions were in the range from 4.07 × 10–8.11 × 10 Ω−1 ·cm−1 . 相似文献
58.
Saeko Yanaka Shigetaka Nishiguchi Rina Yogo Hiroki Watanabe Jiana Shen Hirokazu Yagi Takayuki Uchihashi Koichi Kato 《International journal of molecular sciences》2022,23(4)
Immunoglobulin G (IgG) adopts a modular multidomain structure that mediates antigen recognition and effector functions, such as complement-dependent cytotoxicity. IgG molecules are self-assembled into a hexameric ring on antigen-containing membranes, recruiting the complement component C1q. In order to provide deeper insights into the initial step of the complement pathway, we report a high-speed atomic force microscopy study for the quantitative visualization of the interaction between mouse IgG and the C1 complex composed of C1q, C1r, and C1s. The results showed that the C1q in the C1 complex is restricted regarding internal motion, and that it has a stronger binding affinity for on-membrane IgG2b assemblages than C1q alone, presumably because of the lower conformational entropy loss upon binding. Furthermore, we visualized a 1:1 stoichiometric interaction between C1/C1q and an IgG2a variant that lacks the entire CH1 domain in the absence of an antigen. In addition to the canonical C1q-binding site on Fc, their interactions are mediated through a secondary site on the CL domain that is cryptic in the presence of the CH1 domain. Our findings offer clues for novel-modality therapeutic antibodies. 相似文献
59.
Kiyoharu Nakagawa Hirokazu Oda Akira Yamashita Masahiro Okamoto Yoichi Sato Hidenori Gamo Mikka Nishitani-Gamo Kazuyuki Ogawa Toshihiro Ando 《Journal of Materials Science》2009,44(1):221-226
We developed a novel spherical carbon material. The spherical carbon is composed of a high density of carbon nanotubes or
nanofilaments, and includes an oxidized diamond particle as a core. Syntheses of this carbon in high volume with high selectivity
may be possible. It is expected that this carbon will be useful as a catalyst material for fuel cells, electric double-layer
capacitors, etc. 相似文献
60.
Hirokazu Ozaki Atsushi Kara Zixue Cheng 《Quality and Reliability Engineering International》2011,27(7):895-903
In this paper, we investigate service‐level assurance in high‐availability multi‐unit systems using the M‐for‐N backup scheme. M‐for‐N shared protection (backup) systems with priority control (i.e. prioritized protection switching and prioritized re‐housing of repaired units) can be applied to actual telecommunication devices that are subject to service‐level agreement (SLA) involving reliability measures. A priority level is assigned to each end user in such a system and the switching and unit re‐housing process is subject to the priority. The main contribution of this paper is to give a practical computation method of the user‐perceived availability under the priority control. Our case studies for real telecommunication systems reveal the effect of priority control on the user‐perceived availability. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献