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111.
Shin-ichi Inomata Mitsuaki Komoda Hayaki Watanabe Masashi Nomura Tetsu Ando 《Journal of chemical ecology》2000,26(2):443-454
Anadevidia peponis and Macdunnoughia confusa are defoliators of plants in the family Cucurbitaceae and Compositae, respectively, in Japan. GC-MS analyses of crude pheromone gland extracts treated with or without dimethyl disulfide indicated that females of A. peponis produced six monoene acetates and two monoene alcohols and that M. confusa females produced five monoene acetates. These components include (Z)-7-dodecenyl acetate as a major common constituent and three other acetates as minor common constituents. The minor constituents are quite different in blend composition. In addition, with (Z)-7-dodecenyl acetate, an indispensable component for male attraction is (Z)-5-decenyl acetate for A. peponis and (Z)-9-tetradecenyl acetate is essential for M. confusa. Field tests with synthetic lures showed synergistic effects of some other minor components and male attraction of three additional Plusiinae species, Macdunnoughia purissima, Ctenoplusia albostriata, and Chrysodeixis eriosoma, suggesting their reproductive isolation is based in part on pheromonal communication. 相似文献
112.
Kazuaki Yanagisawa Keishiro Ito Chisato Katsuki Kei Kawashima Masashi Shirabe 《Scientometrics》2010,84(3):563-573
An outcome of nuclear safety research (NSR) done by JAERI (Japan Atomic Energy Research Institute) was case studied by the
bibliometric method. (1) For LOCA (loss-of-coolant accident) a domestic share of JAERI in monoclinic research paper was 63%
at the past (20) 1978–1982 but was decreased to 40% at the present 1998–2002. For co-authored papers a domestic share between
JAERI and PS (public sectors) was zero at past (20) but increased to 4% at the present. Research cooperation is active between
Tokyo University and JAERI or between JAERI and Nagoya University. (2) It is revealed that LOCA outputs born by NSR-JAERI
reflected partly to those of the Safety Licensing Guidelines, however, a share of NSR-JAERI could not determined due to the
lack of necessary information in the Guideline. 相似文献
113.
Takatoshi Shindo Hideki Motoyama Toru Miki Mikihisa Saito Akiyori Matsueda Noriyasu Honma Tomohito Hida Kazuo Shinjo Kiyotaka Hayashi Hayato Awazu Katsuhisa Makabe Masato Fujikawa Satoshi Kurihara Masashi Sato 《IEEJ Transactions on Electrical and Electronic Engineering》2016,11(Z2):S28-S33
Nine electric power companies in Japan have been collecting lightning data with lightning location systems. Five years of the lightning data (2009–2013) are summarized and analyzed in this paper. The recent annual number of lightning flashes of which the current is more than 10 kA in Japan is around 1 million. The variations of lightning occurrence characteristics by areas, seasons, and so on, are clarified. Meteorological conditions that may affect lightning occurrence are also discussed. Furthermore, we show that there is a clear correlation between the number of lightning strikes and the outage rate of transmission lines. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
114.
Mechanism‐Based Trapping of the Quinonoid Intermediate by Using the K276R Mutant of PLP‐Dependent 3‐Aminobenzoate Synthase PctV in the Biosynthesis of Pactamycin
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Akane Hirayama Dr. Akimasa Miyanaga Prof. Dr. Fumitaka Kudo Prof. Dr. Tadashi Eguchi 《Chembiochem : a European journal of chemical biology》2015,16(17):2484-2490
Mutational analysis of the pyridoxal 5′‐phosphate (PLP)‐dependent enzyme PctV was carried out to elucidate the multi‐step reaction mechanism for the formation of 3‐aminobenzoate (3‐ABA) from 3‐dehydroshikimate (3‐DSA). Introduction of mutation K276R led to the accumulation of a quinonoid intermediate with an absorption maximum at 580 nm after the reaction of pyridoxamine 5′‐phosphate (PMP) with 3‐DSA. The chemical structure of this intermediate was supported by X‐ray crystallographic analysis of the complex formed between the K276R mutant and the quinonoid intermediate. These results clearly show that a quinonoid intermediate is involved in the formation of 3‐ABA. They also indicate that Lys276 (in the active site of PctV) plays multiple roles, including acid/base catalysis during the dehydration reaction of the quinonoid intermediate. 相似文献
115.
Wataru Naito Masashi Kamo Yuichi Iwasaki 《The Science of the total environment》2010,408(20):4271-4284
In recent years, due to concerns on the potential effects of zinc on aquatic biota, zinc is receiving particular attention from regulatory agencies. A comprehensive exposure and risk assessment of zinc in Japanese surface waters was conducted to provide a scientific basis for developing realistic risk reduction measures for zinc. Emissions from corrosion contribute approximately 37% of the total zinc emissions to surface water in Japan. The zinc concentration distributions estimated using 12 years of monitoring data from 2075 sites by a maximum likelihood method indicated that the mean concentrations have gradually declined. The threshold concentrations (HC5 and PHC5) derived from organism- and population-level species sensitivity distributions were estimated to be 27 and 107 μg/L for total zinc, respectively. The risk characterization identified that during 1991-2002, 14.5-26.8% of the monitoring sites likely exceeded the HC5, whereas only 0.7-3.5% likely exceeded the PHC5. Evaluation of the effect of stormwater runoff to zinc concentrations in a river showed that zinc concentrations in river water increased significantly from roadway drainage flowing into the river. The cost-effectiveness analyses demonstrated that enforcement of the zinc national effluent standard may be effective at a certain level for public water areas in Japan; however, the degree of the effectiveness is highly dependent on the characteristics (e.g., sources and background) of the watersheds. An emissions and exposure assessment along with cost-effectiveness analysis is crucial for developing realistic and appropriate ecological risk management of zinc. The zinc RAD in Japan illustrated that in any “state-of-the science” method used, some degree of ecological risk from zinc can be observed in some Japanese water environments. On the other hand, zinc is a beneficial material for human industrial activities. Because zinc is an element, its role in industrial activities would be difficult to be substituted by other metals with less toxicity. In addition to improving science-based risk assessment methodologies which often focus on the toxicological perspectives, it is important to develop a more robust framework considering a trade-off between a damage in ecosystem and a benefit in human activities. Zinc can be a role model for it. 相似文献
116.
Masashi Imanaka Shigeo Tomita Suguru Kanda Mitsuteru Fujieda Kimikazu Sasa Jens Olaf Pepke Pedersen Hiroshi Kudo 《Journal of aerosol science》2010,41(5):468-474
To investigate the contribution of ions to gas nucleation, we have performed experiments on the formation of water droplets in H2O/N2 and H2O/Ar gas mixtures by irradiation with a 20 MeV proton beam and by positive corona discharge. The size of the formed nanoparticles was measured using a differential mobility analyzer equipped with a Faraday cup electrometer. Using the proton beam, droplets around 10 nm in diameter were observed for both positively and negatively charged particles, but none were found when the corona discharge was used. This implies the importance of the presence of both positive and negative ions for the formation of nanosize droplets, which attract each other by Coulomb interactions, enhancing the collision frequency and leading to the formation of the 10 nm droplets. 相似文献
117.
The Sonogashira-Hagihara polymerization of 3′,5′-diiodo-N-α-tert-butoxycarbonyl-l-tyrosine methyl ester (1) and 3′,5′-diiodo-N-α-tert-butoxycarbonyl-O-methyl-l-tyrosine methyl ester (2) with para-diethynylbenzene (3) was carried out to obtain optically active poly(m-phenyleneethynylene-p-phenyleneethynylene)s [poly(1) and poly(2)] with Mn’s ranging from 9900 to 15,000 in 80-87% yields. Poly(1) exhibited intense CD signals in DMSO and THF, but did not in CH2Cl2, indicating that it took a predominantly one-handed helical conformation in the former two solvents. On the other hand, there was no evidence for poly(2) to take a helical structure in these solvents. Poly(1) turned the CD sign at 390 nm from plus to minus in DMSO/H2O = 9/1 (v/v) by the addition of NaOH. Alkaline hydrolysis of ester moieties of poly(1) and poly(2) gave the corresponding polymers having carboxy groups [poly(1a) and poly(2a)]. Poly(1a) and poly(2a) increased the CD intensity by the addition of NaOH. 相似文献
118.
Takahito Itoh Takahiro Sakakibara Masashi Tamura Masataka Kubo 《Electrochimica acta》2010,55(4):1419-1424
The hyperbranched polymers (HBP-SA-Acs) with both a sulfonic acid group as a functional group and an acryloyl group as a cross-linker at terminals in different ratios of sulfonic acid group/acryloyl group (SO3H/Ac) were successfully synthesized as a new thermally stable proton-conducting electrolyte. The cross-linked hyperbranched polymer electrolyte membranes (CL-HBP-SAs) were prepared by thermal polymerizations of the HBP-SA-Acs using benzoyl peroxide, and their ionic conductivities under dry condition and thermal properties were investigated. The ionic conductivities of the CL-HBP-SAs were found to be in the range of 2.2 × 10−4 to 3.3 × 10−6 S/cm, depending upon the SO3H unit contents, at 150 °C under dry condition, and showed the Vogel-Tamman-Fulcher (VTF) type temperature dependence, indicating that proton transfer is cooperated by local polymer chain motion. All CL-HBP-SAs were thermally stable up to 260 °C, and they had suitable thermal stability as electrolyte membranes for the high-temperature fuel cells under dry condition. Fuel cell measurement using a single membrane electrode assembly cell with a cross-linked electrolyte membrane was successfully performed under non-humidified condition. It was demonstrated that applying the concept of dry polymer system to proton conduction is one possible approach toward high-temperature fuel cells. 相似文献
119.
Fumitaka Kudo Dr. Atsushi Motegi Kazutoshi Mizoue Dr. Tadashi Eguchi Prof. Dr. 《Chembiochem : a European journal of chemical biology》2010,11(11):1574-1582
FD‐891 is a 16‐membered cytotoxic antibiotic macrolide that is especially active against human leukemia such as HL‐60 and Jurkat cells. We identified the FD‐891 biosynthetic (gfs) gene cluster from the producer Streptomyces graminofaciens A‐8890 by using typical modular type I polyketide synthase (PKS) genes as probes. The gfs gene cluster contained five typical modular type I PKS genes (gfsA, B, C, D, and E), a cytochrome P450 gene (gfsF), a methyltransferase gene (gfsG), and a regulator gene (gfsR). The gene organization of PKSs agreed well with the basic polyketide skeleton of FD‐891 including the oxidation states and α‐alkyl substituent determined by the substrate specificities of the acyltransferase (AT) domains. To clarify the involvement of the gfs genes in the FD‐891 biosynthesis, the P450 gfsF gene was inactivated; this resulted in the loss of FD‐891 production. Instead, the gfsF gene‐disrupted mutant accumulated a novel FD‐891 analogue 25‐O‐methyl‐FD‐892, which lacked the epoxide and the hydroxyl group of FD‐891. Furthermore, the recombinant GfsF enzyme coexpressed with putidaredoxin and putidaredoxin reductase converted 25‐O‐methyl‐FD‐892 into FD‐891. In the course of the GfsF reaction, 10‐deoxy‐FD‐891 was isolated as an enzymatic reaction intermediate, which was also converted into FD‐891 by GfsF. Therefore, it was clearly found that the cytochrome P450 GfsF catalyzes epoxidation and hydroxylation in a stepwise manner in the FD‐891 biosynthesis. These results clearly confirmed that the identified gfs genes are responsible for the biosynthesis of FD‐891 in S. graminofaciens. 相似文献