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61.
Sadamasu K Tabei Y Shinkai T Hasegawa M Kaneko S Hirai A Nakama A Ishizaki N Odagiri M Kamata S Yano K Kai A Morozumi S 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2006,47(1):1-8
A PCR method for the effective detection of Coxiella burnetii in commercially available mayonnaise was developed. Sample preparations were isolated from 50 g portions of each mayonnaise product by four successive extraction steps in phosphate buffer with 2.0 M NaCl. These extracts were then centrifuged at 20,000 x g for 60 min. DNA was isolated from the solution containing the precipitate with a commercial kit, and amplified quantitatively using real-time PCR that targeted the com1 region of C. burnetii. The recoveries of C. burnetii from 2 kinds of commercial mayonnaise specimens, with a baseline control of 1 x 10(7) particles of the Nine Mile phase II strain, were 85.0 +/- 6.0% and 72.0 +/- 0.4%, respectively. The determination limit of this method was 500 C. burnetii particles per 50 g of mayonnaise. The DNA specimens isolated from 50 different commercial mayonnaise samples sold in Tokyo using this method were amplified using both nested PCR and real-time PCR. No contamination by C. burnetii was detected in any of the mayonnaise samples. 相似文献
62.
Sasaki K Morita M Matsumoto N Sasaki D Hirano S Ohmura N Igarashi Y 《Journal of Bioscience and Bioengineering》2012,114(1):64-69
The aim of this study was to show the effectiveness of the membrane free bioelectrochemical system (BES) using three electrodes on inhibition of methanogenesis and construction of hydrogen fermentation from the artificial garbage slurry. The electrical redox-potential on the working electrode was adjusted to -1.0V (vs. Ag/AgCl) that has positive effect on methanogenesis. The redox-potential on the counter electrode was measured to be 1.6V. The pH in the effluents was 5.5-6.4. Hydrogen production rate at the cathode side was similar to that at the anode side and much higher than that calculated from current, and reached a maximum of 2445±815 (average±standard deviation) mL?L(-1)?d(-1) at an organic loading rate of 58.7g dichromate chemical oxygen demand per L d(-1). Methane production was negligible throughout the experiment. Acetate and butyrate were the main products of the fermentation using a BES; these offered favorable conditions for hydrogen production. The bacterial community in the bioelectrochemical hydrogen fermentor differed from that in the methanogenic seed sludge and included hitherto unknown species. These results show that high redox-potential on the anodic electrode and acidic pH in the membrane free BES can be utilized for hydrogen fermentation from the artificial garbage slurry by avoiding methanogenesis. 相似文献
63.
Arito Yozu Masashi Hamada Takuya Sasaki Shin-ichi Tokushige Shoji Tsuji Nobuhiko Haga 《Advanced Robotics》2017,31(1-2):80-87
AbstractPatients with gait disorders often use bilateral crutches along with their own two legs. It is a kind of quadrupedalism. Crutch-assisted gait is usually described and evaluated qualitatively. In this study, we developed a system to quantify the spatial and temporal parameters for crutch-assisted quadrupedalism. Our system consists of walkway hardware and our originally developed software. We specifically extended the measurable area to 1200 mm × 4800 mm, large enough to measure crutch gait. Using our system, we could describe crutch gait precisely. Our system has a capability to evaluate differences between patients and changes within a patient. 相似文献
64.
Experimental visualization of lithium diffusion in LixFePO4 总被引:2,自引:0,他引:2
Chemical energy storage using batteries will become increasingly important for future environmentally friendly ('green') societies. The lithium-ion battery is the most advanced energy storage system, but its application has been limited to portable electronics devices owing to cost and safety issues. State-of-the-art LiFePO4 technology as a new cathode material with surprisingly high charge-discharge rate capability has opened the door for large-scale application of lithium-ion batteries such as in plug-in hybrid vehicles. The scientific community has raised the important question of why a facile redox reaction is possible in the insulating material. Geometric information on lithium diffusion is essential to understand the facile electrode reaction of LixFePO4 (0相似文献
65.
Urata C Yamauchi Y Aoyama Y Imasu J Todoroki S Sakka Y Inoue S Kuroda K 《Journal of nanoscience and nanotechnology》2008,8(6):3101-3105
A new type of hierarchically porous materials is fabricated by assembling mesoporous nanoparticles via spray drying. Well-dispersed mesostructured silica nanoparticles (MSN), whose particle size distribution was narrow in the range of 20 nm and 50 nm, were prepared by a thermal deposition method. By spray drying a MSN suspension, MSN were assembled into spherical secondary particles. After calcination, the spherical particles have two types of mesopores, mesopores of 3 nm in size inside of calcined MSN and larger inter-nanoparticle mesopores of about 15-20 nm. This hierarchical pore system should provide nanospaces for efficient mass transport of guest species with different sizes. 相似文献
66.
N Fujioka R Akazawa K Ohashi M Fujii M Ikeda M Kurimoto 《Canadian Metallurgical Quarterly》1999,73(3):2401-2409
We examined the effects of interleukin-18 (IL-18) in a mouse model of acute intraperitoneal infection with herpes simplex virus type 1 (HSV-1). Four days of treatment with IL-18 (from 2 days before infection to 1 day after infection) improved the survival rate of BALB/c, BALB/c nude, and BALB/c SCID mice, suggesting innate immunity. One day after infection, HSV-1 titers were higher in the peritoneal washing fluid of control BALB/c mice than in that of IL-18-treated mice. A genetic deficiency of gamma interferon (IFN-gamma), however, diminished the survival rate and the inhibition of HSV-1 growth at the injection site in the mice. Anti-asialo GM1 treatment had no influence on the protective effect of IL-18 in infected mice. IL-18 augmented IFN-gamma release in vitro by peritoneal cells from uninfected mice, while no appreciable IFN-gamma production was found in uninfected mice administered IL-18. Although IFN-gamma has the ability to induce nitric oxide (NO) production by various types of cells, administration of the NO synthase inhibitor NG-monomethyl-L-arginine resulted in superficial loss of the improved survival, but there was no influence on the inhibition of HSV-1 replication at the injection site in IL-18-treated mice. Based on these results, we propose that IFN-gamma produced before HSV-1 infection plays a key role as one of the IL-18-promoted protection mechanisms and that neither NK cells nor NO plays this role. 相似文献
67.
68.
Effect of Excess PbO on the Densification of PLZT Ceramics 总被引:1,自引:0,他引:1
Byung-Moo Song Doh-Yeon Kim Shin-ichi Shirasaki Hiroshi Yamamura 《Journal of the American Ceramic Society》1989,72(5):833-836
The densification behavior and electrical properties of PLZT ceramics as a function of excess PbO in the starting powder have been investigated. The hot-pressed PLZT ceramics, prepared from powders containing 0% to 4% excess PbO, were transparent, and their electrical properties were similar in general. PLZT with PbO deficiency up to 1.4 mol% from stoichiometry can be regarded as a single phase-PLZT. 相似文献
69.
Qing-qing LU Takuto KANETSUKI Shin-ichi YAMASAKI Ryoichi YAMADA Takahiro WATANABE Noriyoshi TSUCHIYA 《中国有色金属学会会刊》2014,24(6):1880-1889
Focusing on the origin of the heavy metal, this study aims to build an imputed method to estimate the heavy metal content in river water by making a distinction between the heavy metal of natural origins and that caused by human activities. Supported by GIS, Kosaka watershed within the Hokuroku basin was divided into several sub-watershed polygons and the outflows of water and Cu were calculated for each polygon. Compared with the natural origin, the dominant Cu emissions affected the river water more significantly in local. Based on the mass balance closure, the heavy metal content of Cu in the Kosaka River was estimated by the conflux accumulation of tributaries and mine drainages. The estimated Cu concentrations were checked by comparing with the actually measured values at monitoring points along the Kosaka River and the results are coincidence with each other in general. It is revealed that the mainstream water quality could be estimated by seizing the water quality of upstream tributaries and human drainages. 相似文献
70.