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101.
Toru Katsumata Hiromi Kubo Shuji Komuro Hiroaki Aizawa 《Journal of the American Ceramic Society》2014,97(6):1704-1707
Photoluminescence spectrum, trap depths, and densities of trapped carriers of CaAl2O4:Eu phosphor crystals doped with rare‐earth elements were studied using the thermally stimulated luminescence technique. Trap depths and densities of the specimens vary with rare‐earth elements doped as the auxiliary activators. Tm and Nd are found to be effective for the strong afterglow phosphorescence peaking at λ = 442 nm for several hours after the excitation. CaAl2O4:Eu phosphor crystals doped with Nd and Tm include high density of carriers trapped at E = 0.59 and 0.52 eV, respectively. 相似文献
102.
Akira Kaieda Dr. Masashi Takahashi Hiromi Fukuda Dr. Rei Okamoto Dr. Shinji Morimoto Masayuki Gotoh Takahiro Miyazaki Yuri Hori Satoko Unno Dr. Tomohiro Kawamoto Dr. Toshimasa Tanaka Dr. Sachiko Itono Terufumi Takagi Dr. Hiroshi Sugimoto Dr. Kengo Okada Dr. Weston Lane Dr. Bi-Ching Sang Dr. Kumar Saikatendu Dr. Shinichiro Matsunaga Dr. Seiji Miwatashi 《ChemMedChem》2019,14(24):2093-2101
We identified novel potent inhibitors of p38 mitogen-activated protein (MAP) kinase using a structure-based design strategy, beginning with lead compound, 3-(butan-2-yl)-6-(2,4-difluoroanilino)-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one ( 1 ). To enhance the inhibitory activity of 1 against production of tumor necrosis factor-α (TNF-α) in human whole blood (hWB) cell assays, we designed and synthesized hybrid compounds in which the imidazo[4,5-b]pyridin-2-one core was successfully linked with the p-methylbenzamide fragment. Among the compounds evaluated, 3-(3-tert-butyl-2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-6-yl)-4-methyl-N-(1-methyl-1H-pyrazol-3-yl)benzamide ( 25 ) exhibited potent p38 inhibition, superior suppression of TNF-α production in hWB cells, and also significant in vivo efficacy in a rat model of collagen-induced arthritis (CIA). In this paper, we report the discovery of potent, selective, and orally bioavailable imidazo[4,5-b]pyridin-2-one-based p38 MAP kinase inhibitors. 相似文献
103.
Tokuyuki Yoshida Yasuo Yoshioka Hideki Takahashi Kazuki Misato Takahide Mori Toshiro Hirai Kazuya Nagano Yasuhiro Abe Yohei Mukai Haruhiko Kamada Shin-ichi Tsunoda Hiromi Nabeshi Tomoaki Yoshikawa Kazuma Higashisaka Yasuo Tsutsumi 《Nanoscale research letters》2014,9(1):532
Although amorphous silica nanoparticles are widely used in the production of food products (e.g., as anticaking agents), there is little information available about their absorption and biological effects after oral exposure. Here, we examined the in vitro intestinal absorption and in vivo biological effects in mice of orally administered amorphous silica particles with diameters of 70, 300, and 1,000 nm (nSP70, mSP300, and mSP1000, respectively) and of nSP70 that had been surface-modified with carboxyl or amine groups (nSP70-C and nSP70-N, respectively). Analysis of intestinal absorption by means of the everted gut sac method combined with an inductively coupled plasma optical emission spectrometer showed that the intestinal absorption of nSP70-C was significantly greater than that of nSP70. The absorption of nSP70-N tended to be greater than that of nSP70; however, the results were not statistically significant. Our results indicate that silica nanoparticles can be absorbed through the intestine and that particle diameter and surface properties are major determinants of the degree of absorption. We also examined the biological effects of the silica particles after 28-day oral exposure in mice. Hematological, histopathological, and biochemical analyses showed no significant differences between control mice and mice treated with the silica particles, suggesting that the silica nanoparticles evaluated in this study are safe for use in food production. 相似文献
104.
Norihisa Saeki Hiromi Sakamoto Teruhiko Yoshida 《International journal of molecular sciences》2014,15(5):7958-7973
Gastric cancer (GC) is one of the major malignant diseases worldwide, especially in Asia. It is classified into intestinal and diffuse types. While the intestinal-type GC (IGC) is almost certainly caused by Helicobacter pylori (HP) infection, its role in the diffuse-type GC (DGC) appears limited. Recently, genome-wide association studies (GWAS) on Japanese and Chinese populations identified chromosome 1q22 as a GC susceptibility locus which harbors mucin 1 gene (MUC1) encoding a cell membrane-bound mucin protein. MUC1 has been known as an oncogene with an anti-apoptotic function in cancer cells; however, in normal gastric mucosa, it is anticipated that the mucin 1 protein has a role in protecting gastric epithelial cells from a variety of external insults which cause inflammation and carcinogenesis. HP infection is the most definite insult leading to GC, and a protective function of mucin 1 protein has been suggested by studies on Muc1 knocked-out mice. 相似文献
105.
Ko Ikeda Yoshinori Nakamura Kiyoshi Masumoto Hiromi Shima 《Journal of the American Ceramic Society》1997,80(10):2672-2676
Unpolarized optical spectra were measured in the wavelength range 322–1666 nm by the diffuse reflection technique from spinel powders synthesized in the system MgAl2 O4 –MgCr2 O4 . The spectra were interpreted by the crystal-field theory on the basis of trigonally distorted spinel octahedra with D3d symmetry. For chromium-rich solid solutions, including the MgCr2 O4 end-member, results after peak fittings showed octahedral D3d local symmetry around Cr3+ ions, identical to the crystallographic site symmetry. For chromium-poor solid solutions, however, octahedral C3v local symmetry was suggested around Cr3+ ions, different from the D3d crystallographically expected. 相似文献
106.
Y. Nagasawa Y. Tachikawa E. Yamaguchi N. Tada T. Miura A. Itoh 《Advanced Synthesis \u0026amp; Catalysis》2016,358(2):178-182
A new catalytic method was developed for photo‐oxidizing the methyl group on aromatic heterocycles such as benzothiazole, benzoxazole, and quinoline to produce the corresponding aldehyde. This is the first report of the metal‐free catalytic synthesis of benzothiazole‐2‐carboxaldehydes using molecular oxygen as the terminal oxidant.
107.
A novel vinyl ether-type RAFT agent, benzyl 2-(vinyloxy)ethyl carbonotrithioate (BVCT) was synthesized for various block copolymers via the combination of living cationic polymerization of vinyl ethers and reversible addition−fragmentation chain transfer (RAFT) polymerization. The novel BVCT–trifluoroacetic acid adduct play an important role to produce well-defined block copolymers, which is both as a cationogen under EtAlCl2 initiation system in the presence of ethyl acetate for living cationic polymerization and a RAFT agent for blocks by RAFT polymerization. The resulting polymer, poly(vinyl ether)s, by living cationic polymerization had a high number average α-end functionality (≥0.9) as determined by both 1H NMR and MALDI-TOF-MS spectrometry. In addition, this poly(vinyl ether)s worked well as a macromolecular chain transfer agent for RAFT polymerization. The RAFT polymerization of radically polymerizable monomers was conducted in toluene using 2,2′-azobis(isobutyronitrile) at 70 °C. For example, a double thermoresponsive block copolymer (MOVE61-b-NIPAM150) consisting of 2-methoxyethyl vinyl ether (MOVE) and N-isopropylacrylamide (NIPAM) was prepared via the combination of living cationic polymerization and RAFT polymerization. The block copolymer reversibly formed and deformed micellar assemblies above the phase separation temperature (Tps) of poly(NIPAM) block in water. This BVCT is not only functioned as an initiator, but also acted as a monomer. When BVCT was copolymerized with MOVE by living cationic polymerization, followed by graft copolymerization with NIPAM via RAFT polymerization, well-defined graft copolymers (MOVEn-co-BVCTm)-g-NIPAMx (n = 62–73, m = 1–9, x = 19–214) were successfully obtained. However, no micelle formed in water above Tps of poly(NIPAM) graft chain unlike the case of block copolymers. 相似文献
108.
Saito M. Sugimori Y. Kohama Y. Yoshida Y. Miura N. Ishikuro H. Sakurai T. Kuroda T. 《Solid-State Circuits, IEEE Journal of》2010,45(1):134-141
An inductive-coupling programmable bus for NAND flash memory access in solid state drive (SSD) is presented. Compared to the conventional SSD, this wireless interface using relayed transmission reduces power consumption to 1/2, I/O circuit-layout area to 1/40, and achieves a data rate of 2 Gb/s in 0.18 ?m CMOS process. In addition, since this wireless interface enables one package to contain 64 chips, the number of packages is reduced to 1/8. 相似文献
109.
Iwao Matsuya Ryota Tomishi Maya Sato Kiyoshi Kanekawa Yoshihiro Nitta Motoichi Takahashi Satoru Miura Yasutsugu Suzuki Tomohiko Hatada Ryuta Katamura Takashi Tanii Shuichi Shoji Akira Nishitani Iwao Ohdomari 《IEEJ Transactions on Electrical and Electronic Engineering》2011,6(3):266-272
We have developed a novel sensor that enables us to measure the relative story displacement of a building structure in real time. This lateral displacement sensor (LDS) is composed of a light‐emitting diode (LED) array, which is fixed on the ceiling, and a position‐sensitive detector (PSD) unit, which is placed on the floor. We optimized the LDS to achieve high accuracy in lateral displacement measurement. The accuracy was evaluated to be 60 µm by conducting shaking table tests. Two LDSs were implemented in an actual building equipped with an active variable stiffness (AVS) system, and the building was vibrated with seismic waveforms by an exciter placed on the rooftop. The seismic displacement of the second floor relative to the first floor was measured using the LDS. Furthermore, the inclination angle of the second floor could be measured using the LDS during the seismic vibration. Using the AVS system, we realized the residual displacement of the second floor without inducing damage to the building, and succeeded in real‐time residual displacement measurement for the first time. These results indicate that the LDS is useful for the health diagnosis of a building structure. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
110.
Hirotami Nakano Takeshi Tanabe Masanobu Naitoh Yoshiki Kubota Tsuyoshi Morita Toyoaki Kimura Makoto Matsukawa Yushi Miura 《Electrical Engineering in Japan》2000,131(4):1-10
In a balanced three‐phase system, the three‐phase current distortion factor of three‐phase ac power sources has been expressed by applying the conventional single‐phase current distortion factor, which is defined for a single‐phase system. However, in an unbalanced three‐phase system, it is difficult to express the three‐phase current distortion factor for distorted three‐phase ac currents by means of the conventional single‐phase current distortion factor. For instance, the conventional current distortion factors for three‐phase ac currents are usually different from each other in the unbalanced three‐phase system. To solve the above problem, this paper proposes a novel definition of the three‐phase current distortion factor. The proposed three‐phase current distortion factor is quite effective for the unbalanced three‐phase system as well as the balanced three‐phase system. © 2000 Scripta Technica, Electr Eng Jpn, 131(4): 1–10, 2000 相似文献