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排序方式: 共有613条查询结果,搜索用时 31 毫秒
101.
Feunai Agape Papalii Tautau Minoru Izumi Emiko Matsunaga Yujiro Higuchi Kaoru Takegawa 《Journal of Applied Glycoscience》2020,67(3):87
α-L-Rhamnosidases (α-L-Rha-ases, EC 3.2.1.40) are glycosyl hydrolases (GHs) that hydrolyze a terminal α-linked L-rhamnose residue from a wide spectrum of substrates such as heteropolysaccharides, glycosylated proteins, and natural flavonoids. As a result, they are considered catalysts of interest for various biotechnological applications. α-L-rhamnose (6-deoxy-L-mannose) is structurally similar to the rare sugar α-L-mannose. Here we have examined whether microbial α-L-Rha-ases possess α-L-mannosidase activity by synthesizing the substrate 4-nitrophenyl α-L-mannopyranoside. Four α-L-Rha-ases from GH78 and GH106 families were expressed and purified from Escherichia coli cells. All four enzymes exhibited both α-L-rhamnosyl-hydrolyzing activity and weak α-L-mannosyl-hydrolyzing activity. SpRhaM, a GH106 family α-L-Rha-ase from Sphingomonas paucimobilis FP2001, was found to have relatively higher α-L-mannosidase activity as compared with three GH78 α-L-Rha-ases. The α-L-mannosidase activity of SpRhaM showed pH dependence, with highest activity observed at pH 7.0. In summary, we have shown that α-L-Rha-ases also have α-L-mannosidase activity. Our findings will be useful in the identification and structural determination of α-L-mannose-containing polysaccharides from natural sources for use in the pharmaceutical and food industries. 相似文献
102.
Kevinsanny Saburo Okazaki Osamu Takakuwa Yuhei Ogawa Koichi Okita Yusuke Funakoshi Junichiro Yamabe Saburo Matsuoka Hisao Matsunaga 《Fatigue & Fracture of Engineering Materials & Structures》2019,42(5):1203-1213
Tension‐compression fatigue tests were performed on two types of Ni‐based superalloy 718 with different microstructures in which small artificial defects of various sizes and shapes were introduced. The susceptibility of the fatigue strength to the defects varied significantly with the microstructure morphology, ie, a smaller grain size made the alloy more susceptible to defects. The fatigue limit as a small‐crack threshold was successfully predicted using the parameter model. The evaluation of the fatigue limit was classified into the following three stages depending on the defect size: (a) harmless defect regime, (b) small‐crack regime, and (c) large‐crack regime. Such a classification enabled comprehensive evaluation of the fatigue limit in a wide range of defect size, considering (a) defect size over a range of small crack to large crack and (b) characteristics of matrix represented by grain size and hardness. 相似文献
103.
Yuriko Okazaki Shinichiro Okazaki Shingo Asamoto Pang‐jo Chun 《Computer-Aided Civil and Infrastructure Engineering》2020,35(8):775-792
The growing demand for a more efficient maintenance of concrete bridges requires a model that tracks the deterioration of each bridge based on inspection data. Although it has been expected that machine learning could be applied to this problem, inspection data sparsely distributed over time are not suitable for machine learning in contrast to the continuous big data usually targeted. This study applies machine learning to a regression model of crack formation and propagation using inspection data to confirm the applicability. It includes the selection of the optimal algorithm, development of the model based on a novel methodology, and factor analysis using the model. Accordingly, the model was constructed by Gaussian process regression and it could appropriately extract the differences in the progress of crack damage due to multiple influential factors. The results demonstrate the excellent applicability of machine learning even to sparse data. 相似文献
104.
The heat transfers between the heating plane and the granular materials in both the “Stationary heating-plane type” and the “Moving heating-plane type” of the conductive-heating agitated dryers were discussed mainly from the view point of the scale-up of the dryer. Under the condition of complete mixing in the bed of bulk materials, the heat transfer models proposed for both the two types of dryers can predict the heat transfer coefficients in any sizes of the dryers. However, the complete mixing is not usually accomplished in the large scale of dryer. Hence, an “Incomplete mixing model” was proposed to estimate the effect of the incompleteness of mixing on the heat transfer coefficient. In this model, the incompleteness of mixing can be apparently taken into consideration only by increasing the contact time. 相似文献
105.
There has been considerable interest in silicon-on-insulator (SOI) technology recently because of its potential applications in VLSI. CMOS circuits in SOI have higher speed because of the absence of substrate capacitance, and freedom from latch-up because of dielectric isolation. Recently, memory circuits like DRAMs have reached the physical limits of what is possible in two dimensions, and hence there is a growing need for 3-dimensional circuits. SOI offers a possible avenue to realise such 3-D circuits and thus lead the way to the next generation of memories and integrated circuits. 相似文献
106.
S Takahashi E Narimatsu H Asanuma M Okazaki A Okazaki K Hirata M Mori T Chiba N Sato K Kikuchi 《Canadian Metallurgical Quarterly》1995,52(5):371-375
A case of laryngeal paraganglioma in a 25-year-old female is reported. The site of the tumor was the left aryepiglotic fold and ventricular band. The diagnosis was made by histology and immunohistochemistry medial thyrotomy was performed in order to remove a bilateral carotid paraganglioma. We analyzed 76 cases reported in the world literature, clinical, histological, prognostic, and therapeutic factors in laryngeal paraglioma. 相似文献
107.
Y Moriwake Y Tohno S Tohno T Minami M Utsumi F Nishiwaki M Yamada H Yamamoto Y Okazaki T Fujii Y Takakura 《Canadian Metallurgical Quarterly》1998,64(1-3):229-235
The relative contents (RCs) of elements in the human menisci from 23 subjects in the age range between 65 and 93 yr were analyzed by inductively coupled plasma atomic emission spectrometry. The RCs of sulfur, calcium, and phosphorus in menisci increased progressively until the 80s, being the highest in the 80s, and thereafter decreased. The RCs of magnesium in menisci increased progressively until the 90s. Regarding the medial and lateral menisci, higher RCs of magnesium and iron, and a lower RC of phosphorus were found in lateral menisci in comparison with those in medial menisci. There were sexual differences in the RCs of calcium and phosphorus of medial and lateral menisci. The RCs of calcium and phosphorus were about 50% higher in women's menisci than in men's. Histological examinations showed that structureless mucoid masses were observed in the menisci, with very high RCs of calcium and phosphorus being detected. 相似文献
108.
This paper attempts to propose a structural model that integrates various factors influencing attitude towards wireless banner ads and intention to access them. This model is applied to empirical data of Japanese mobile users sampled in the greater Tokyo area. First, structural equation modelling is used to test the baseline model. The results show that the model explains mobile users’ perceptual antecedents and consequences well, with all structural paths statistically significant. Second, in the attempt to identify different mobile user groups, a probabilistic cluster analysis is performed. This results in three-cluster groups, consisting of (1) housewives and part-timers, (2) middle-aged white-collar workers and professionals, and (3) students and “parasite singles”. Finally, multigroup analysis is used to examine whether the model operates invariantly across the three-cluster groups. The results indicate significant differences in the paths associated with consumer innovativeness and perceived entertainment between the groups. In closing, managerial implications and future research directions are discussed, while important limitations are recognised. 相似文献
109.
Yamashita N. Kimura T. Fujita Y. Aimoto K. Manabe T. Okazaki S. Nakamura K. Yamashina M. 《Solid-State Circuits, IEEE Journal of》1994,29(11):1336-1343
An integrated memory array processor (IMAP) ULSI with 64 processing elements and a 2-Mb SRAM has been developed for image processing. The chip attains a 3.84 GIPS peak performance through the use of SIMD parallel processing and a 1.28 GByte/s on-chip processor-memory bandwidth. The IMAP is capable of parallel indirect addressing, which increases applications for parallel algorithms. Large power consumption with the wide memory bandwidth is avoided by reducing the number of active sense amplifiers and adopting dynamic power control. Fabricated with a 0.55-μm BiCMOS double layer metal process technology, the IMAP contains 11 million transistors in a 15.1×15.6 mm2 die area 相似文献
110.
Y. Ushigami Y Okazaki N. Abe T. Kumano M. Kikuchi T. Inokuchi 《Journal of Materials Engineering and Performance》1995,4(4):435-440
Thin-gauge 3% Si-Fe with {110}〈001〉 orientation is a suitable material for magnetic devices in the frequency range from 102 to 105 Hz. Low core loss and high permeability in this frequency range are required. With recently developed, highly grain-oriented
materials, physical parameters that affect core losses were investigated as a function of excitation frequency and magnetic
flux density. The relationship between core loss and excitation conditions is classified into four regions. This material
is useful for transformers and inductors, especially for higher flux density application in the middle frequency region (Bm[maximum
excitation magnetic flux density] > 1T, 102 to 103 Hz), such as airplane devices. 相似文献