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991.
Masataka Kubo Hisatomu Yamamoto Takahiro Uno Takahito Itoh Hiroaki Sato 《Polymer Bulletin》2001,47(1):25-30
Summary
α-Amino, ω-carboxyl heterodifunctional poly(methyl methacrylate) was prepared by a living anionic polymerization of methyl
methacrylate using N,N'-diphenylethylenediamine monolithium amide and succinic anhydride as an initiator and terminator, respectively. Its intramolecular
cyclization was carried out to obtain a well-defined cyclic poly(methyl methacrylate).
Received: 27 June 2001/Accepted: 16 July 2001 相似文献
992.
Yamamoto S. Ara T. Oda S. Matsuse K. 《Industry Applications, IEEE Transactions on》2000,36(4):1053-1060
This paper presents a method to predict the direct- and quadrature-axes operational impedances and starting performance of permanent-magnet (PM) motors by a simple standstill response testing method using a small-capacity DC power supply unit. In this method, not only the starting performance but also the direct- and quadrature-axes synchronous machine constants (synchronous, transient, and subtransient reactances) and equivalent circuit constants are calculated. This proposed strategy, tentatively named the DC decay testing method, is carried out on a 3.7-kW 200-V 22. A 100-Hz four-pole interior PM motor with a damper winding. The results measured by on-load tests and those predicted by the proposed method on starting performance demonstrate the validity and usefulness of the proposed method 相似文献
993.
Differences in properties of myofibrillar proteins from bovine semitendinosus muscle after hydrostatic pressure or heat treatment 总被引:1,自引:0,他引:1
Eun‐Jung Lee Yun‐Ji Kim Nam‐Hyouck Lee Seok‐In Hong Katsuhiro Yamamoto 《Journal of the science of food and agriculture》2007,87(1):40-46
Hydrostatic pressure (HP) and heat treatments of myofibrillar proteins have both been shown to induce protein denaturation, but different gel formation properties result from these treatments. To characterise differences in the properties of proteins resulting from HP or heat treatment, Ca‐ and Mg‐ATPase activities (ATP, adenosine triphosphate) and protein solubility in 0.1 and 0.6 mol L?1 KCl buffers (pH 7) were evaluated in this study. The inactivation rate of Ca‐ATPase of myofibrillar proteins (Mf) induced by HP was slower than that of Mg‐ATPase at each of the tested pressures. However, the inactivation rate of Ca‐ATPase induced by heating was faster than that of Mg‐ATPase at each of the tested temperatures. The level of soluble proteins in Mf suspension induced by HP in 0.1 mol L?1 KCl buffer increased with increasing pressure up to 400 MPa and then decreased slightly at 500 MPa. However, the level of soluble proteins in Mf suspension induced by heat treatment in 0.1 mol L?1 KCl buffer increased with increasing temperature up to 55°C. According to the results of sodium dodecyl sulfate polyacrylamide gel electrophoresis, the levels of soluble myosin heavy chain and actin in Mf suspension induced by HP in 0.6 mol L?1 KCl buffer decreased simultaneously at pressures higher than 300 MPa. The level of soluble MHC in 0.6 mol L?1 KCl buffer decreased gradually with increasing temperature, but there were no changes in the level of soluble actin in 0.6 mol L?1 KCl buffer with increasing temperature up to 50°C. These results showed that the mechanism of HP‐induced protein denaturation was different from the mechanism underlying heat‐induced protein denaturation. Copyright © 2006 Society of Chemical Industry 相似文献
994.
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
995.
In general all detonation waves have cellular structure formed by the trajectory of the triple points.This paperaims to investigate experimentally the propagation of detonation in narrow gaps for hydrogen-oxygen-argonmixtures in terms of various gap heights and gap widths.The gap of total length 1500 mm was constructed bythree pair of stainless plates,each of them was 500 mm in length,which were inserted in a detonation tube.Thegap heights were varied from 1.2 mm to 3.0 mm while the gap widths were varied from 10 mm to 40 mm.Variousargon dilution rates were tested in the present experiments to change the size of cellular structure.Attempts havebeen made by means of reaction front velocity,shock front velocity,and smoked foil to record variations of cel-lular structure inside the gaps.A combination probe composed of a pressure and an ion probe detected the arrivalof the shock and the reaction front individually at one measurement point.Experimental results show that thenumber of the triple points contained in detonation front decreases with decrease in the gap heights and gapwidths,which lead to larger cellular structures.For mixtures with low detonability,cell size is affected by a cer-tain gap width although conversely cell size is almost independent of gap width.From the present result it wasfound that detonation propagation inside the gaps is strongly governed by the gap height and effects of gap widthis dependent on detonability of mixtures. 相似文献
996.
Shigeaki Yamamoto Yoshiaki Ukita Kozo Mochiji Yuichi Utsumi 《Electrical Engineering in Japan》2012,178(4):49-54
Polytetrafluoroethylene (PTFE) is a very attractive material for various fields because of its chemical resistance, insulation properties, and hydrophobic properties. However, it is difficult to fabricate PTFE microstructures with conventional techniques such as semiconductor processes or micromachining. We have succeeded in the fabrication of high‐aspect‐ratio microfluidics parts from PTFE by direct in‐vacuum photo‐etching utilizing synchrotron radiation (SR) at energy levels from 2 to 12 keV. This paper presents an analysis of the mechanisms of the PTFE microfabrication process and describes newly discovered processing characteristics of PTFE. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 178(4): 49–54, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21152 相似文献
997.
998.
Jia Shi Riku Kanoya Yurina Tani Sodai Ishikawa Rino Maeda Sana Suzuki Fumiya Kawanami Naoko Miyagawa Katsuhiko Takahashi Teruaki Oku Ami Yamamoto Kaori Fukuzawa Motowo Nakajima Tatsuro Irimura Nobuaki Higashi 《International journal of molecular sciences》2022,23(9)
We examined whether sulfated hyaluronan exerts inhibitory effects on enzymatic and biological actions of heparanase, a sole endo-beta-glucuronidase implicated in cancer malignancy and inflammation. Degradation of heparan sulfate by human and mouse heparanase was inhibited by sulfated hyaluronan. In particular, high-sulfated hyaluronan modified with approximately 2.5 sulfate groups per disaccharide unit effectively inhibited the enzymatic activity at a lower concentration than heparin. Human and mouse heparanase bound to immobilized sulfated hyaluronan. Invasion of heparanase-positive colon-26 cells and 4T1 cells under 3D culture conditions was significantly suppressed in the presence of high-sulfated hyaluronan. Heparanase-induced release of CCL2 from colon-26 cells was suppressed in the presence of sulfated hyaluronan via blocking of cell surface binding and subsequent intracellular NF-κB-dependent signaling. The inhibitory effect of sulfated hyaluronan is likely due to competitive binding to the heparanase molecule, which antagonizes the heparanase-substrate interaction. Fragment molecular orbital calculation revealed a strong binding of sulfated hyaluronan tetrasaccharide to the heparanase molecule based on electrostatic interactions, particularly characterized by interactions of (−1)- and (−2)-positioned sulfated sugar residues with basic amino acid residues composing the heparin-binding domain-1 of heparanase. These results propose a relevance for sulfated hyaluronan in the blocking of heparanase-mediated enzymatic and cellular actions. 相似文献
999.
Seiichiro Katagiri SungGi Chi Yosuke Minami Kentaro Fukushima Hirohiko Shibayama Naoko Hosono Takahiro Yamauchi Takanobu Morishita Takeshi Kondo Masamitsu Yanada Kazuhito Yamamoto Junya Kuroda Kensuke Usuki Daigo Akahane Akihiko Gotoh 《International journal of molecular sciences》2022,23(9)
KIT is a type-III receptor tyrosine kinase that contributes to cell signaling in various cells. Since KIT is activated by overexpression or mutation and plays an important role in the development of some cancers, such as gastrointestinal stromal tumors and mast cell disease, molecular therapies targeting KIT mutations are being developed. In acute myeloid leukemia (AML), genome profiling via next-generation sequencing has shown that several genes that are mutated in patients with AML impact patients’ prognosis. Moreover, it was suggested that precision-medicine-based treatment using genomic data will improve treatment outcomes for AML patients. This paper presents (1) previous studies regarding the role of KIT mutations in AML, (2) the data in AML with KIT mutations from the HM-SCREEN-Japan-01 study, a genome profiling study for patients newly diagnosed with AML who are unsuitable for the standard first-line treatment (unfit) or have relapsed/refractory AML, and (3) new therapies targeting KIT mutations, such as tyrosine kinase inhibitors and heat shock protein 90 inhibitors. In this era when genome profiling via next-generation sequencing is becoming more common, KIT mutations are attractive novel molecular targets in AML. 相似文献
1000.
R. Ueyama K. Kamada M. Harada T. Ueyama T. Yamamoto K. Kuribayashi K. Koumoto T. Shiosaki 《Journal of Materials Science》2001,36(2):371-379
Physical and electrical properties of three types of Ag-Pd pastes, which consist of different metal fine powders, i.e., a coprecipitated powder, an agglomerated alloy powder made by heat treatment and a pulverized alloy powder produced by improved pulverization method, have been studied. The paste prepared from pulverized alloy powder showed a higher film packing density (6.3 g/cm3) than those made of the other powders. The film consisting of pulverized alloy powder showed a lower expansion at around 500 °C, a lower shrinkage from 700 °C to 1100 °C and a lower electric resistivity. The results indicated that the paste which consists of an pulverized Ag-Pd alloy powder was superior in performance to the other two pastes for an internal electrode material of multilayer ceramic device. 相似文献