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51.
Fire Safety Performance of Japanese Traditional Wood/Soil Walls and Implications for the Restoration of Historic Buildings in Urban Districts 总被引:2,自引:0,他引:2
Yuji Hasemi Noboru Yasui Michitaka Akizuki Koichi Kinoshita Koichi Yamamoto Masatomo Yoshida Yoshihide Tamura Mariko Takeda 《Fire Technology》2002,38(4):391-402
Grass-root research activities to clarify fire safety performance of Japanese traditional wooden construction are introduced. The activities aim to resolve conflict between the restoration of historic buildings and the reduction of risk and hazard of urban fires. Among various activities, scope and results of fire resistance tests on traditional soil wall assemblies supported by timber frame are reported in detail. The test results indicate an encouraging prospect for the rational fire safety assessment of historic buildings and further development of fire-safe traditional constructions for the restoration of historic buildings and historic urban districts. 相似文献
52.
Takahashi Taiki; Sakaguchi Kikue; Oki Mariko; Hasegawa Toshikazu 《Canadian Metallurgical Quarterly》2008,1(1):7
Hormones in the brain have many types of visceral influences on social behavior and economic decision-making. Although hormone-associated visceral effects attract attention in neuroeconomics, little is known regarding the relationship between sex hormones and hyperbolic discounting. Furthermore, although the “discount factor” (a parameter indicating patience in intertemporal choice) is economically relevant and has neural correlates, most neuroeconomic studies on intertemporal choice have been focusing on neuromodulation of logged discount rates, which sometimes results in difficulty in interpretation. This study was aimed to examine linear correlations between chronic sex hormone levels and hyperbolic discount factors of gains and losses in healthy male students. Participants’ salivary sex hormone (testosterone) levels were also assessed. We observed a positive linear relationship between testosterone levels and hyperbolic discount factor of gains; while no linear relationship between testosterone levels and discount factor of losses was observed. The results indicate that (i) chronic elevation in testosterone may be associated with patience (indicated by a discount factor) in intertemporal choice on gains, (ii) testosterone is unrelated to discounting of delayed losses. Implications for sex hormone-related visceral effects on problematic decision-making (e.g. addiction) and possible neuroendocrinological mechanism (e.g. conversion of testosterone into female hormones in the brain) are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
Nakamura N Ito K Takahashi M Hashimoto K Kawamoto M Yamanaka M Taniguchi A Kamatani N Gemma N 《Analytical chemistry》2007,79(24):9484-9493
An electrochemical DNA chip using an electrochemically active intercalator and DNA probe immobilized on a gold electrode has been developed for genetic analysis. In this study, the six polymorphisms associated with rheumatoid arthritis (RA), N-acetyltransferase2 (NAT2) gene polymorphisms T341C, G590A, and G857A, methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms C677T and A1298C, and serum amyloid A1 (SAA1) gene promoter polymorphism C-13T were simultaneously detected by the electrochemical DNA chip and the loop-mediated isothermal amplification (LAMP) method, which is a novel technique for DNA amplification. Human genomic DNAs were extracted from blood, and the targets containing the six polymorphisms were amplified by the LAMP method. A sample containing the six LAMP products was reacted with the electrochemical DNA chip using a DNA detection system that controls hybridization reaction, washing, electrochemical detection, and data analysis automatically. A total of 31 samples were genotyped by this method, and the results were completely consistent with those determined by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis or the PCR direct sequence analysis. The time required for this method was only 2 h, and operations were very simple. Therefore, this method is expected to contribute to personalized medicine based on genotype. 相似文献
54.
Ohmae M Sakaguchi K Kaneto T Fujikawa S Kobayashi S 《Chembiochem : a European journal of chemical biology》2007,8(14):1710-1720
Keratan sulfate (KS) oligomers with well-defined structures were synthesized by keratanase II (KSase II)-catalyzed transglycosylation. N-Acetyllactosamine [Galbeta(1-->4)GlcNAc; LacNAc] oxazoline derivatives with sulfate groups at the C-6 (1 a) and both the C-6 and the C-6' (1 b) were prepared as transition-state analogue substrate monomers for KSase II. Monomer 1 a was effectively oligomerized by the enzyme under weak alkaline conditions, to give alternating 6-sulfated KS oligomers (2 a) in good yields, and with total control of regioselectivity and stereochemistry. KSase II also recognized 1 b, which provided fully 6-sulfated KS oligomers (2 b) in good yields under similar conditions. Nonsulfated LacNAc oxazoline was difficult to oligomerize enzymatically. These results imply that the catalysis mechanism of KSase II involves a sugar oxazolinium ion that requires the 6-sulfate group in the GlcNAc residue not only in hydrolysis of KS chains, but also in oligomerization of oxazoline monomers. This is the first report of KSase II-catalyzed transglycosylation to form beta(1-->3)-glycosidic bond through a substrate-assisted mechanism. 相似文献
55.
Image analysis of morphological change during arachidonic acid production by Mortierella alpina 1S-4
Higashiyama K Fujikawa S Park EY Okabe M 《Journal of Bioscience and Bioengineering》1999,87(4):489-494
The changes in mycelial morphology during arachidonic acid (AA) production by Mortierella alpina 1S-4 were investigated using an image analysis system. Cultivation was performed in a 10-kl fermentor, and the culture broth was separated into two fractions by sieving (0.5 mm aperture size): the filament fraction (F-fraction, <0.5 mm), and the pellet fraction (P-fraction, >0.5 mm). The effect of the mycelial morphology in each fraction on AA production was analyzed. As a result, a product distribution in the culture broth wherein the AA content in the mycelia of the P-fraction was observed to be higher than that in the mycelia of the F-fraction throughout the cultivation. Morphological analysis of the P-fraction revealed that the hairy pellets became smooth because the mycelia on the pellet surface were shaved off; some pellets were broken and reduced in size. The shaved-off mycelia from the hairy pellets surface moved into the F-fraction and aggregated there. From the above findings, it was likely that the low AA content in the F-fraction was due to mycelial damage during the cultivation. In addition, the morphology of the hairy pellets was found to contribute to an increase in the viscosity of culture broth. 相似文献
56.
57.
The corrosion behavior of various austenitic stainless steels and high-alloy steels has been studied in simulated fluidized bed boiler environment to develop a new corrosion resistant austenitic stainless steel for the superheater tube. The superheater is usually not installed within the bed position, which is different from the evaporator installed within the bed position. Therefore, the superheater tubes are exposed to an oxidizing environment; but it is also necessary to estimate the corrosion resistance of the steels in a reducing environment. It is already known that the high temperature corrosion behavior in conditions where CaSO4 is coated on the steels is more important than the erosion of the superheater tubes. The main results in this present study are as follows: The Nb bearing steels and low C steels showed good resistance to high-temperature corrosion in CaSO4/CaO, e.g. 347, 304L and HR3C. The corrosion rate of all steels used increased with increase in temperature, particularly at temperatures higher than 650°C. Internal penetration was not detected at temperatures lower than 550°C, but it was detected at temperatures higher than 600°C, in particular, higher than 650°C. The corrosion thickness loss was almost the same as the internal penetration depth at 700 and 750°C in the 300 series steels placed in CaSO4/CaO, including the fine grained 347 steel, while the internal penetration depth was larger than the corrosion thickness loss in high-alloyed materials such as Alloy 800 and 310 steels. At temperatures higher than 800°C, the same result was also obtained for the fine grained 347 steel. The corrosion during exposure to oxidizing or reducing gases without CaSO4/CaO or CaS was slight, but when the test specimens were placed in CaSO4/CaO or CaS, the corrosion rate sharply increased, regardless of the atmospheric gas composition. Cr, Si, Mn (less than 5 %), Mo and Nb are beneficial elements while C, Cu and Al are harmful elements. From the above results, the following steel was developed for high temperature corrosion resistance in CaSO4/CaO: low C-22/25Cr-17/25Ni-3/5Mn-(2Mo)-Nb-0.08/0.2N-Al-(B). 相似文献
58.
By means of gel permeation chromatography analysis, the molecular weights and molecular weight distributions of liquefied wood obtained under various liquefaction conditions and species of catalysts were investigated in order to trace the change in the structural characteristics of the liquefied wood. The results indicated that during the liquefaction reaction, wood components were subjected to decomposition, phenolation, and recondensation. The intensities of these reactions depended greatly on the reaction conditions and the species of catalysts, and their competing result determined the structural characteristics of the resulting liquefied wood. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 351–357, 1997 相似文献
59.
Jessica Da Gama Duarte Luke T. Quigley Anna Rachel Young Masaru Hayashi Mariko Miyazawa Alex Lopata Nunzio Mancuso Mikio Mikami Andreas Behren Els Meeusen 《International journal of molecular sciences》2021,22(20)
Ovarian cancers include several disease subtypes and patients often present with advanced metastatic disease and a poor prognosis. New biomarkers for early diagnosis and targeted therapy are, therefore, urgently required. This study uses antibodies produced locally in tumor-draining lymph nodes (ASC probes) of individual ovarian cancer patients to screen two separate protein microarray platforms and identify cognate tumor antigens. The resulting antigen profiles were unique for each individual cancer patient and were used to generate a 50-antigen custom microarray. Serum from a separate cohort of ovarian cancer patients encompassing four disease subtypes was screened on the custom array and we identified 28.8% of all ovarian cancers, with a higher sensitivity for mucinous (50.0%) and serous (40.0%) subtypes. Combining local and circulating antibodies with high-density protein microarrays can identify novel, patient-specific tumor-associated antigens that may have diagnostic, prognostic or therapeutic uses in ovarian cancer. 相似文献