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991.
Masahiro Hirata Naoki Kogab Hitoshi Shinjo Haruhiro Fujita Gustave Gintzburger Akira Miyazaki 《International journal of remote sensing》2013,34(4):507-516
As vegetation classification on the highly diverse rangeland is an inevitable procedure in evaluating total forage resources and assessing human impact in large areas, a supervised classification was conducted by satellite image processing using geocoded bands 2, 3 and 4 of Landsat 5 Thematic Mapper (TM) images, dated 13 April 1994 in the Abdal Aziz Mountain study area in northeastern Syria. The rangeland was categorized into six classes according to the plant contacts of dominant shrubs (Artemisia herba-alba and Noaea mucronata) and herbaceous plants. In addition, cultivated fields were categorized into two classes. An average classification accuracy of 85% in the supervised processing and an average ground verification accuracy of 81% on the Landsat-estimated vegetation classes were achieved for the rangeland. These show that a 30m X 30m resolution of the Landsat TM image had the ability to recognize vegetation at six sub-divided community levels, and the successful classification was conducted on the whole rangeland of the study area. The distinctive feature of this work is that this vegetation classification using Landsat TM images was accomplished at the level of classifying a A. herba-alba and N. mucronata dominant community into six sub-community classes. This detailed vegetation classification was conducted with the final aim of forage resource estimation and human impact assessment in mind. 相似文献
992.
Yuichiro Tameda Akimichi Taketa Jeremy D. Smith Manobu Tanaka Masaki Fukushima Charles C.H. Jui Kenichi Kadota Fumio Kakimoto Takeshi Matsuda John N. Matthews Shoichi Ogio Hiroyuki Sagawa Nobuyuki Sakurai Tatsunobu Shibata Masahiro Takeda Stanton B. Thomas Hisao Tokuno Yoshiki Tsunesada Shigeharu Udo 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2009,609(2-3):227-234
The Telescope Array Project is an experiment designed to observe Ultra High Energy Cosmic Rays via a “hybrid” detection technique utilizing both fluorescence light detectors (FDs) and scintillator surface particle detectors (SDs). We have installed three FD stations and 507 SDs in the Utah desert, and initiated observations from March 2008. The northern FD station reuses 14 telescopes from the High Resolution Fly's Eye, HiRes-I station. Each of the two southern FD stations contains 12 new telescopes utilizing new FADC electronics. Each telescope is instrumented with a camera composed of 256 PMTs. Since the detectors are composed of many PMTs and each PMT detects fluorescence photons together with the vast amount of night sky background, a sophisticated triggering system is required. In this paper, we describe the trigger electronics of these new FD stations. We also discuss performance of the FDs with this triggering system, in terms of efficiencies and apertures for various detector configurations. 相似文献
993.
Kazunori Ichikawa Hiroshi Akamatsu Koji Yamasaki Masahiro Horita Yukiharu Uraoka 《材料科学与工程:中英文B版...》2013,(6):375-378
Low temperature polyclstaline Si thin film transistor (LTPS-TFT) used for a liquid crystal display (LCD) is obtained by crystallizing a-Si (amorphous Si). Although excimer laser is commonly used for crystallization, green laser crystallization attracts attention in recent years due to two a-Si layers in staked substrate (a-Si/SiO2/a-Si/quartz) are crystallized only by one time of irradiation. In order that this stacked layer structure is the same as the structure of a flash memory, this technology is applied to improvement in a performance of a flash memory. As a result, even when laser irradiation from the back is performed, two Si layers simulataneous crystallization is possible. Compared with the irradiation from front, the field-effect mobilities of the irradiation from the back improved about 10 times. Furthermore, in order that the retention time is improving significantly, it indicated that the quality of the oxide film between two layers improves. This technology is a technology promising for the improvement in a performance of a flash memory. 相似文献
994.
Franz A. Mautner Jörg H. Albering Masahiro Mikuriya Salah S. Massoud 《Inorganic chemistry communications》2010,13(6):796-799
The reaction of Cu(ClO4)2, N,N,N′,N″,N″-pentamethylethylenetriamine (pmedien) and sodium dicyanamide (Nadca) in aqueous medium led to the isolation of {[Cu(pmedien)(μ1,5-dca)]2(ClO4)2,[Cu(pmedien)(μ1,5-dca)]n(ClO4)n} (1). The complex was structurally and magnetically characterized. Single X-ray crystallography for 1 reveals the existence of two independent molecules in the unit cell: dinuclear doubly bridging complex and a 1-D polymeric chain with dca in both cases acting as a μ1,5-bridging ligand via the terminal nitrile nitrogen atoms. Magnetic susceptibility measurements of the complex showed that the Cu(II) ions are weakly coupled with ferromagnetic interaction in the dinuclear unit (Jd = 0.9 cm–1) and antiferromagnetic interaction in the polymeric chain (Jc = ? 0.6 cm? 1). 相似文献
995.
Pyranose 2-oxidases catalyze the oxidation of various pyranose sugars at the C2 position. However, their potential application for detecting sugars other than glucose in blood is hindered by relatively high activity towards glucose. In this study, in order to find a mutant enzyme with enhanced specificity for 1,5-anhydro-D-glucitol (1,5-AG), which is a biomarker for diabetes mellitus, we conducted site-directed mutagenesis of pyranose 2-oxidase from the basidiomycete Phanerochaete chrysosporium ( Pc POX). Considering the three-dimensional structure of the substrate-binding site of Pc POX and the structural difference between glucose and 1,5-AG, we selected alanine 551 of Pc POX as a target residue for mutation. Kinetic studies of the 19 mutants of Pc POX expressed as recombinant proteins in E. coli revealed that the ratio of k cat / K m for 1,5-AG to k cat / K m for glucose was three times higher for the A551L mutant than for wild-type Pc POX. Although the A551L mutant has lower specific activity towards each substrate than the wild-type enzyme, its increased specificity for 1,5-AG makes it a promising lead for the development of POX-based 1,5-AG detection systems. 相似文献
996.
Kiyohiko Igarashi Satoshi Kaneko Motomitsu Kitaoka Masahiro Samejima 《Journal of Applied Glycoscience》2020,67(2):51
Cellobiose dehydrogenase (CDH) is a flavocytochrome catalyzing oxidation of the reducing end of cellobiose and cellooligosaccharides, and has a key role in the degradation of cellulosic biomass by filamentous fungi. Here, we use a lineup of glucose/xylose-mixed β-1,4-linked disaccharides and trisaccharides, enzymatically synthesized by means of the reverse reaction of cellobiose phosphorylase and cellodextrin phosphorylase, to investigate the substrate recognition of CDH. We found that CDH utilizes β-D-xylopyranosyl-(1→4)-D-glucopyranose (Xyl-Glc) as an electron donor with similar K m and k cat values to cellobiose. β-D-Glucopyranosyl-(1→4)-D-xylopyranose (Glc-Xyl) shows a higher K m value, while xylobiose does not serve as a substrate. Trisaccharides show similar behavior; i.e., trisaccharides with cellobiose and Xyl-Glc units at the reducing end show similar kinetics, while the enzyme was less active towards those with Glc-Xyl, and inactive towards those with xylobiose. We also use docking simulation to evaluate substrate recognition of the disaccharides, and we discuss possible molecular mechanisms of substrate recognition by CDH. 相似文献
997.
Akihiro Maeta Masahiro Katsukawa Yasushi Inomoto Yaeko Hayase Kyoko Takahashi 《Journal of food science》2020,85(10):3570-3576
998.
We investigated improvement of workability (viscosity), storage stability, and curing ability of thiirane resin for adhesive applications. The viscosity of bisphenol‐F thiirane resin was lower than that of bisphenol‐A thiirane resin, especially at low temperatures, thus improving ease of handling. Addition of diphenyl decyl phosphite improved its storage stability to a level similar to that of bisphenol‐A epoxy resin. The curing of bisphenol‐F thiirane resin increased three times faster by adding 2,4,6‐tris(dimethylaminomethyl)phenol (DMP‐30) as a tertiary amine. In applications of this new thiirane resin as civil and architectural adhesives, a superior curing ability at low temperature was attained. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2953–2957, 2001 相似文献
999.
Mitsuhiro Arisawa Masahiro Hamada Ikuko Takamiya Masahiko Shimoda Shiro Tsukamoto Yasuhiko Arakawa Atsushi Nishida 《Advanced Synthesis \u0026amp; Catalysis》2006,348(9):1063-1070
We have developed a method for preparing a recyclable and environmentally benign organopalladium catalyst for the Heck reaction supported on sulfur‐terminated gallium arsenide(001). This three‐component catalyst, {Pd}‐S‐GaAs(001), exhibited high stability and activity, furthermore, it tolerated reuse in 10 runs of the Heck reaction (average yield, 97 %) under aerobic conditions. The sulfur layer was very important to stabilize this catalyst. Only trace amounts of Pd were leached from this catalyst to the reaction mixture, as measured by ICP‐mass. The valence of immobilized Pd was zero by XPS spectrometry. 相似文献
1000.
Kawahara M Ogo Y Ueda H Nagamune T 《Protein engineering, design & selection : PEDS》2004,17(10):715-719
Structure-based design of antibody/cytokine receptor chimeras has permitted a growth signal transduction in response to non-natural ligands such as fluorescein-conjugated BSA as mimicry of cytokine-cytokine receptor systems. However, while tight on/off regulation is observed in the natural cytokine receptor systems, many chimeras constructed to date showed residual growth-promoting activity in the absence of ligands. Here we tried to reduce the basal growth signal intensity from a chimera by engineering the transmembrane domain (TM) that is thought to be involved in the interchain interaction of natural cytokine receptors. When the retroviral vectors encoding the chimeras with either the wild-type erythropoietin receptor (EpoR) TM or the one bearing two mutations in the leucine zipper motif were transduced to non-strictly interleukin-6-dependent 7TD1 cells, a tight antigen-dependent on/off regulation was attained, also demonstrating the first antigen-mediated genetically modified cell amplification of non-strictly factor-dependent cells. The results clearly indicate that the TM mutation is an effective means to improve the growth response of the antibody/receptor chimera. 相似文献