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51.
The authors present a method by which to construct a fast N*N self-routing space switch network with identical 2*2 switch elements. This network is nonblocking and employs O(N log/sup 3/ N) switch elements; each element uses just two bits of the output port address for switching control.<> 相似文献
52.
Haruki Sakagami Akira Tsubouchi Akio Saito 《Advanced Synthesis \u0026amp; Catalysis》2024,366(3):533-540
Herein, we describe metal-free fluorocyclization of 2-alkynylbenzoates by N-fluoropyridinium salts. The present method allows the selective synthesis of 4-fluoroisocoumarins and 3,4,4-trifluoroisochromanones by minor modification of the reaction conditions. 相似文献
53.
Yuitsu Otsuka Koki Sato Shigekazu Yano Haruki Kanno Wasana Suyotha Hiroyuki Konno Koki Makabe Toki Taira 《Journal of Applied Glycoscience》2022,69(3):49
The GH-16 type β-1,3-glucanase (BgluC16MK) gene of Lysobacter sp. MK9-1 was cloned to study its antifungal activities. BgluC16MK displays amino acid sequence similarity with GluC from L. enzymogenes strain N4-7. BgluC16MK includes a signal sequence, a catalytic domain and carbohydrate-binding module family 6-type β-glucan binding domain (B-GBD). The expression of the BgluC16MK gene in Escherichia coli without the signal sequence resulted in antifungal activity at a dose of 0.6-0.8 nmol/disk. However, BgluC16MK displayed antifungal activity at a dose of 0.025 nmol/disk in combination with Chi19MK. Substrate-specific assay revealed that purified BgluC16MK hydrolyzed insoluble curdlan more readily than the soluble substrate. Furthermore, to explore the binding selectivity of B-GBD of BgluC16MK, we constructed a fusion protein (B-GBD-GFP) using the B-GBD and green fluorescent protein. The activity of the fusion protein against various substrates indicates that B-GBD was selective for glucans with β-1,3-linkages. An additional study demonstrated the binding ability of B-GBD-GFP to the cell-wall of living fungi, such as T. reesei and Aspergillus oryzae. These findings suggest that BgluC16MK can be utilized to generate antifungal enzyme preparations and that the fusion protein B-GBD-GFP can be used to identify the fungal cell surface structure using β-glucans. 相似文献
54.
Akina Obara Mari Ogawa Yoichi Oyama Yoshihiro Suzuki Masaru Kono 《International journal of molecular sciences》2023,24(1)
The green alga Aegagropila linnaei often forms spherical aggregates called “marimo” in Lake Akan in Japan. In winter, marimo are exposed to low water temperatures at 1–4 °C but protected from strong sunlight by ice coverage, which may disappear due to global warming. In this study, photoinhibition in marimo was examined at 2 °C using chlorophyll fluorescence and 830 nm absorption. Filamentous cells of A. linnaei dissected from marimo were exposed to strong light at 2 °C. Photosystem II (PSII) was markedly photoinhibited, while photosystem I was unaffected. When the cells with PSII damaged by the 4 h treatment were subsequently illuminated with moderate repair light at 2 °C, the maximal efficiency of PSII was recovered to the level before photoinhibition. However, after the longer photoinhibitory treatments, PSII efficiency did not recover by the repair light. When the cells were exposed to simulated diurnal light for 12 h per day, which was more ecological, the cells died within a few days. Our results showed new findings of the PSII repair at 2 °C and serious damage at the cellular level from prolonged high-light treatments. Further, we provided a clue to what may happen to marimo in Lake Akan in the near future. 相似文献
55.
To obtain fundamental information about hydrogen transfer, the relationships between hydrogen donor ability and chemical structure of model compounds representing donor solvents is studied using gas chromatography,1H n.m.r. and computing calculation methods. The order of the model compounds in terms of the ability as donor solvent to release hydrogen is: decalin < tetralin < 1,2-dihydronaphthalene < < 1,4-dihydronaphthalene. This trend closely correlates with the difference in binding energies of the hydroaromatic compounds and their radicals, determined by intermediate neglect of differential overlap (INDO) calculation. Electron spin resonance spectroscopy (e.s.r.) confirms that radical species are created after heat-treatment of the donor compounds. The ability of model compounds representing coal to accept hydrogen is assessed from a comparison of the1H n.m.r. spectra. It is established that donor and acceptor efficacies are dependent upon chemical structure. 相似文献
56.
Ezaki M. Kumagai H. Toyoda K. Obara M. 《IEEE journal of selected topics in quantum electronics》1995,1(3):841-847
The surface modification of semiconductors by laser-induced surface electromagnetic wave (SEW) etching was investigated. With the novel etching method using a holographic exposure system, submicron periodic dot structures were fabricated directly on semiconductor substrates (n-InP, n-GaAs, and InGaAs-InP). Making use of laser polarization dependence in this etching system, a variety of surface modifications could be achieved on the semiconductors. In particular, in the case of using the s-polarization light, periodic submicron dot structures with a geometrical diameter down to 80 nm could be obtained directly using a single-step process without a mask. The InGaAs-InP dot structures were studied optically by means of photoluminescence spectroscopy, and the blue shift of the photoluminescence energy up to 5.36 meV was observed for the smallest dots, which displayed a lateral quantization 相似文献
57.
K Yamazaki K Sato K Shizume Y Kanaji Y Ito T Obara T Nakagawa T Koizumi R Nishimura 《Canadian Metallurgical Quarterly》1995,80(2):473-479
Using a highly sensitive bioassay for TSH, in which human thyroid follicles incorporate 125I and release de novo synthesized thyroid hormone into the culture medium, the thyrotropic activities of various hCG preparations were studied. Under the culture conditions employed, bovine TSH (bTSH) was approximately 6- to 9-fold more active than human TSH (hTSH). Highly purified hCG prepared from urine of normal pregnant women (CR 127) had only a trivial thyrotropic activity equipotent to 0.00022 microU bTSH/U hCG or 0.0013 microU hTSH/U hCG (19.7 microU hTSH/mg hCG). Hybrid hCG (AB1ER) also elicited low thyrotropic activity (14.0 microU hTSH/mg), whereas crude hCG had moderate thyrotropic activity (0.041 hTSH microU/U hCG or 127 microU/mg protein). Deglycosylated hCG, a very weak LH/hCG receptor agonist, was the most potent agonist in thyroid follicles (588 microU hTSH/mg protein). hCGs purified from urine of patients with trophoblastic tumors had greater TSH-like activity (37-84 microU hTSH/mg protein) than purified hCG. Asialo-hCG purified from a patient with choriocarcinoma had very potent TSH-like activity (468 microU hTSH/mg). Submaximal doses of bTSH and hCG variants produced additive stimulation of thyroid function. Furthermore, the thyrotropic effect of hCG was inhibited by anti-TSH receptor antibody obtained from patients with myxedema. These in vitro findings suggest that although hCG is reported to exert potent cAMP-stimulating activity on rat thyroid-like cells (FRTL-5) and Chinese hamster ovary cells transfected with hTSH receptor complementary DNA (0.092-0.72 microU hTSH/U hCG), the thyrotropic activity induced by authentic hCG in human thyroid follicles is too weak to cause hyperthyroidism in normal pregnancy. However, hCG produced by some trophoblastic tumors, particularly asialo-hCG, has potent thyrotropic activity sufficient to cause clinically overt hyperthyroidism when produced excessively. 相似文献
58.
S Nakajima Y Uchiyama K Yoshida H Mizukawa E Haruki 《Canadian Metallurgical Quarterly》1998,26(3-4):365-373
The effect of Ginseng Radix Rubra (Red ginseng) on human vascular endothelial cells was examined. Red ginseng was found to promote the proliferation of vascular endothelial cells, inhibit the production but promote the decomposition of endothelin, which is known to constrict blood vessels and raise blood pressure as well as accelerated the synthesis of nitric oxide, which is known to have an angio-tonic effect. Furthermore, Red ginseng was observed to increase the production of Interleukin 1 beta, which is known to play important roles in the homeostatic activities of the human body such as immunity and inflammation as well as increasing the production of tissue plasminogen activators, which suppress the formation of thrombin in the blood coagulation and fibrinolysis mechanisms. It is suggested that Red ginseng has the effect of accelerating endothelial cells proliferation and of promoting physiological activities. 相似文献
59.
“Immittance converter” is short for “impedance–admittance converter.” The immittance converter has an input impedance that is proportional to the admittance of the load connected across output terminals. In this converter, the output current is proportional to the input voltage and the input current is proportional to the output voltage. Consequently, it converts a constant voltage source into a constant current source and a constant current source into a constant voltage source. It is well known that the quarter‐wavelength transmission line shows immittance conversion characteristics. However, it has very long line length for the switching frequency, and is not suitable for power electronics application. Thus, we proposed immittance converters that consist of lumped elements L, C and show improved immittance conversion characteristics at a resonant frequency. In this paper, we propose a T‐LCLC‐type immittance converter, which has the transitive configuration and both advantages of T‐LCL‐ and π‐CLC‐type immittance converters. We show voltage–current transformation characteristics and frequency characteristics and efficiency characteristics of the T‐LCLC immittance converter. These characteristics were determined analytically and experimentally. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 142(3): 57–63, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10095 相似文献
60.
Kiyoshi Ohishi Toshimasa Miyazaki Koichi Inomata Daiichi Koide Haruki Tokumaru 《Electrical Engineering in Japan》2006,156(4):60-68
This paper proposes a new robust feedforward tracking servo system for optical disk recording systems in the case of a sudden disturbance for the optical disk recording system. In optical recording systems, the tracking servo system must suppress tracking error below its tolerance. This paper designs the robust feedback control system by using the coprime factorization and disturbance observer. The proposed robust feedback control system suppresses the sudden disturbance caused by walking and running. The detecting signal of optical disk recording systems is only a tracking error. Hence, the feedforward controller of the proposed tracking control system is constructed based on both Zero Phase Error Tracking (ZPET) control theory and prediction of tracking error. The experimental results point out that the proposed tracking servo system has a quick and precise tracking response and keeps the residual tracking error below its tolerance. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 156(4): 60– 68, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20257 相似文献