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951.
Minamida K Kaneko M Ohashi M Sujaya IN Sone T Wada M Yokota A Hara H Asano K Tomita F 《Journal of Bioscience and Bioengineering》2005,99(6):548-554
The growth of DFA III-assimilating bacteria in the intestines of rats fed 3% DFA III for 2 weeks was examined. Sixty-four percent of the DFA III intake had been assimilated on day 3 of ingestion, and almost all of the DFA III was assimilated at the end of the experiment. The DFA III-assimilating bacterium, Ruminococcus productus, in DFA III-fed rats was in the stationary state of 10(8)-10(9) cells/g dry feces within a week from 10(6) cells/g dry feces on day 1 of DFA III ingestion. The number of R. productus cells was associated with the amount of DFA III excreted in the feces. The acetic acid produced from DFA III by R. productus lowered the cecal pH to 5.8. In control-fed rats and DFA III-fed rats, 94% of secondary bile acids and 94% of primary bile acids, respectively, were accounted for in the total bile acids analyzed. DFA III ingestion increased the ratio of primary bile acids and changed the composition of fecal bile acids. In conclusion, R. productus assimilated DFA III, produced short chain fatty acids, and the cecal pH was lowered. The acidification of rat intestine perhaps inhibited secondary bile acid formation and decreased the ratio of secondary bile acids. Therefore, it is expected that DFA III may prevent colorectal cancer and be a new prebiotic candidate. 相似文献
952.
A phase-shifting interferometry (PSI) with equal phase steps by use of a frequency-tunable diode laser and a Fabry-Perot cavity is proposed for the Carré algorithm. The measurement accuracy of the Carré algorithm depends on the equality of the phase steps. Using the Fabry-Perot cavity as a highly stable optical frequency reference, a high degree of phase step equality can be realized in PSI with an optical frequency shift. Our experimental scheme realizes an optical frequency step equality higher than 5.1 x 10(-5) and a measurement repeatability of lambda/800. 相似文献
953.
Yasuhiro Awakura Masami Aoki Atsushi Tsuchiya Hiroshi Majima 《Metallurgical and Materials Transactions B》1989,20(5):555-565
The diffusion coefficients of NiCl2, ZnCl2, and CdCl2 in the aqueous solution systems of MC12 and MC12-HC1 were measured at 298 K using a diaphragm-cell method. The data are listed as a function of molar concentrations of MC12 at the HC1 concentrations of 0, 0.1, 0.5, 1.0, and 2.0 mol dm-3. It was found that the concentration dependencies of the diffusion coefficients for these metal chlorides in single-electrolyte
solutions differed from each other. This could be explained in terms of changes in the mean activity coefficients of chloride
and in the viscosities of those solutions. The diffusion coefficient of metal chloride in MC12-HC1 solution was greatly affected by the HC1 concentration; however, the behavior of the diffusion coefficients varied, depending
on the kind of chloride involved. In NiCl2-HCl solutions, an increase in HC1 con-centration caused a decrease in the diffusion coefficient value, while in ZnCl2-HCl solutions, the addition of 2 mol dm-3 HC1 caused an increase in the diffusion coefficient of ZnCl2. These phenomena are quite different from those of the sulfate systems reported in our previous work. It was also demonstrated
that the concentration dependency of the diffusion coefficients of MC12 in aqueous MC12-HC1 solutions could be attributed to the diffusion potential as well as the changes in the mean activity coefficient and
viscosity.
Masami Aoki, formerly Graduate Student, Department of Met-allurgy, Kyoto University. 相似文献
954.
Cant Noel W. Chambers Dean C. Cowan Andrew D. Liu Irene O.Y. Satsuma Atsushi 《Topics in Catalysis》2000,10(1-2):13-20
Reactions which can produce and consume isocyanic acid (HNCO) over two types of catalysts active for the reduction of nitrogen oxides have been investigated. More than 1000 ppm HNCO can be produced by the reduction of 3000 ppm NO with H2/CO mixtures over a Pt/SiO2 catalyst. Complete hydrolysis of HNCO to ammonia and carbon dioxide occurs if even weakly catalytic materials, such as CeO2/SiO2 and BaO/SiO2, are placed downstream. Isocyanic acid is also involved as an intermediate in the reaction of nitromethane over CoZSM5 and CuZSM5 under the conditions of hydrocarbon SCR. In the initial stages of reaction there is complete conversion through to N2 with CuZSM5 but the process stops at ammonia with CoZSM5 at temperatures below 350°C. In both cases, but especially with CoZSM5, isocyanic acid becomes observable as the catalyst deactivates during continuous exposure at temperatures below about 290°C. In situ FTIR measurements indicate that deactivation is due to a reaction between isocyanic acid and ammonia which generates cyclic striazine compounds. 相似文献
955.
Crack propagation in multilayer piezoelectric actuators made of Pb((Ni1/3 Nb2/3 ), Ti, Zr)O3 ceramics with an interdigital electrode configuration was observed dynamically under an applied cyclic electric field using charge coupled device microscopy. The crack was observed only under a high electric field, and it healed under zero field. The crack was initiated at the internal electrode edge and propagated from the electrode edge in three directions. The electric-field-induced displacement was measured simultaneously with the propagation. The displacement of the multilayer actuator became gradually smaller and asymmetric with respect to the sign of the field with increased driving cycle. 相似文献
956.
A. Doria G. P. Gallerano E. Giovenale A. Casini C. Cucci M. Picollo M. Poggesi L. Stefani K. Fukunaga M. Tamassia 《Journal of Infrared, Millimeter and Terahertz Waves》2017,38(4):390-402
In this paper, we report on Vis-IR hyperspectral and terahertz imaging investigations carried out on a fresco painting on tavella depicting St. John Baptist, by Alessandro Gherardini (1655–1726). Measurements took place at the Restoration Laboratories of the former “Polo Museale della Toscana,” in Florence, in the framework of the Italy-Japan collaborative project THz-ARTE. We show how the hyperspectral data made it possible to determine the state-of-conservation of Gherardini’s painting, while reflection imaging measurements performed at 97 GHz provided a qualitative evaluation of the position of defects inside the tavella. 相似文献
957.
Corinna Ludovica Koch Dandolo Kaori Fukunaga Yoshei Kohzuma Kyoko Kiriyama Kazutaka Matsuda Peter Uhd Jepsen 《Journal of Infrared, Millimeter and Terahertz Waves》2017,38(4):425-434
Lacquering is considered one of the most representative Asian artistic techniques. While the decorative part of lacquerwares is the lacquer itself, their substructures serve as the backbone of the object itself. Very little is known about these hidden substructures. Since lacquerwares are mostly composed of organic materials, such as urushi, wood, carbon black, and fabrics which are very X-ray transparent, standard X-ray radiography has some problems in achieving clear X-ray radiographic images. Therefore, we wanted to contribute to the understanding of the lacquer manufacturing technique by inspecting the substructures of Asian lacquerwares by means of THz time-domain imaging (THz-TDI). Three different kinds of Asian lacquerwares were examined by THz-TDI, and the outcomes have been compared with those obtained by standard X-radiography. THz-TDI provides unique information on lacquerwares substructures, aiding in the comprehension of the manufacturing technology yielding to these precious artefacts. 相似文献
958.
Tatsuya Shimada Yuki Kudoh Takuya Noguchi Tomohiro Kagi Midori Suzuki Mei Tsuchida Hiromu Komatsu Miki Takahashi Yusuke Hirata Atsushi Matsuzawa 《International journal of molecular sciences》2021,22(11)
Receptor-interacting protein kinase 1 (RIPK1) is a key component of the tumor necrosis factor (TNF) receptor signaling complex that regulates both pro- and anti-apoptotic signaling. The reciprocal functions of RIPK1 in TNF signaling are determined by the state of the posttranslational modifications (PTMs) of RIPK1. However, the underlying mechanisms associated with the PTMs of RIPK1 are unclear. In this study, we found that RING finger protein 4 (RNF4), a RING finger E3 ubiquitin ligase, is required for the RIPK1 autophosphorylation and subsequent cell death. It has been reported that RNF4 negatively regulates TNF-α-induced activation of the nuclear factor-κB (NF-κB) through downregulation of transforming growth factor β-activated kinase 1 (TAK1) activity, indicating the possibility that RNF4-mediated TAK1 suppression results in enhanced sensitivity to cell death. However, interestingly, RNF4 was needed to induce RIPK1-mediated cell death even in the absence of TAK1, suggesting that RNF4 can promote RIPK1-mediated cell death without suppressing the TAK1 activity. Thus, these observations reveal the existence of a novel mechanism whereby RNF4 promotes the autophosphorylation of RIPK1, which provides a novel insight into the molecular basis for the PTMs of RIPK1. 相似文献
959.
960.
Hirohide Takahashi Atsushi Miyagi Lorena Redondo‐Morata Simon Scheuring 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(44):6106-6113
With nanometer lateral and Angstrom vertical resolution, atomic force microscopy (AFM) has contributed unique data improving the understanding of lipid bilayers. Lipid bilayers are found in several different temperature‐dependent states, termed phases; the main phases are solid and fluid phases. The transition temperature between solid and fluid phases is lipid composition specific. Under certain conditions some lipid bilayers adopt a so‐called ripple phase, a structure where solid and fluid phase domains alternate with constant periodicity. Because of its narrow regime of existence and heterogeneity ripple phase and its transition dynamics remain poorly understood. Here, a temperature control device to high‐speed atomic force microscopy (HS‐AFM) to observe dynamics of phase transition from ripple phase to fluid phase reversibly in real time is developed and integrated. Based on HS‐AFM imaging, the phase transition processes from ripple phase to fluid phase and from ripple phase to metastable ripple phase to fluid phase could be reversibly, phenomenologically, and quantitatively studied. The results here show phase transition hysteresis in fast cooling and heating processes, while both melting and condensation occur at 24.15 °C in quasi‐steady state situation. A second metastable ripple phase with larger periodicity is formed at the ripple phase to fluid phase transition when the buffer contains Ca2+. The presented temperature‐controlled HS‐AFM is a new unique experimental system to observe dynamics of temperature‐sensitive processes at the nanoscopic level. 相似文献