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1.
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   
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The biggest issue that must be addressed in promoting widespread use of fuel cell vehicles (FCVs) is to reduce the cost of the fuel cell system. Especially, it is of vital importance to reduce platinum (Pt) loading of catalyst layers (CLs) in the membrane electrode assembly (MEA) of a proton exchange membrane fuel cell (PEMFC). In order to lower the Pt loading of the MEA, mass transport of reactants related to the performance in high current density should be enhanced significantly as well as kinetics of the catalyst, which can result in the better Pt utilization and effectiveness. In this study, we summarized our analytical approach and methods for reduction of Pt loading in CLs. Microstructure, mass transport properties of the reactants, and their relation in CLs were elucidated by applying experimental analyses and computational methods. A simple CL model for IV performance prediction was then established, where experimentally elucidated parameters of the microstructure and the properties in CLs were taken into account. Finally, we revealed the impact of lowering the Pt loading on the transport properties, polarization, and the IV performance.  相似文献   
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Simple Method for Measuring the Peroxide Value in a Colored Lipid   总被引:1,自引:0,他引:1  
We developed a simple method for quantification of the peroxide value (PV) in colored lipids on the basis of the reaction between triphenylphosphine (TPP) and oxidized oil to afford triphenylphosphineoxide (TPPO). Diphenylphosphineoxide (DPPO) was employed as internal standard. The formed TPPO was analyzed by high-pressure liquid chromatography–UV spectroscopy with absorption at 260 nm. The conditions that gave the highest correlative calibration curve between the peak area on the chromatogram and peroxide value were identified: the optimum TPP–oxidized oil mix ratio, reaction temperature, and reaction time were found to be 2:1, 40 °C, and 30 min, respectively. Linear calibration curves, passing through the origin, were obtained for PV versus TPPO and TPPO versus DPPO. The quantification limit for this method was 2.01 pmol hydroperoxyl group, which corresponds to a PV value of 0.2 meq/kg in a 10-mg oil sample. This method was used to measure the PV in colored fats and oils or lipids extracted from dark meat and processed food containing a coloring agent. Though the official method could not measure the PVs in the colored lipids, the method proposed here, which uses an inexpensive chemical reagent and machine, could. The developed method could play an important role for food quality control.  相似文献   
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Silica fibers, which can potentially be used as filters and media for catalysts immobilization, were successfully spun via electrospinning process with precursor prepared through the sol–gel synthesis. Spinnable sols can be obtained only when the molar ratio of water to TEOS is less than 2 which is consistent with the retrospective results derived for other spinning methods. It was confirmed for the first time that the reaction time can be drastically reduced by introducing humidified air, controlled by KCl saturated aqueous solution, during sol–gel process. The size of obtained silica fibers is about 4.5 μm and has a certain degree of flexibility and mechanical strength. Although the specific surface area of as spun fiber was 7.7 m2/g, which is apparently small comparing to generic silica, treatment by boiling water only for 5 min could increase the specific surface area to be about 500 m2/g.  相似文献   
6.
We investigated if complement-mediated enhancement of HIV infection occurs in peripheral blood mononuclear cells (PBMC). In 7 experiments, we evaluated the effect of human complement on HIVIIIB infection in vitro. We measured HIV antigen production on day 4 and found that pre-incubation of HIV with complement led to enhanced production of antigen with a median enhancement of 2.5-fold (range 1.1-6.8). This complement-mediated increase in antigen production was statistically significant (p < 0.02). Complement-mediated enhancement of HIV infection was also tested in CD4 cells enriched from PBMC, and CD4 cells persistently gave higher levels of infection enhancement than PBMC. Thus, CD4 cells appear to be sufficient for complement-mediated enhancement of HIV infection to occur. In addition, we tested if it was possible to detect complement-mediated enhancement of primary HIV isolates in PBMC. We tested 3 isolates and found only a minor effect on antigen production (median enhancement 1.2-fold, range 0.6-1.5). Furthermore, addition of HIV-specific antibodies in combination with complement resulted in enhanced antigen production in 2/3 sera tested. However, the combination of complement and antibodies resulted in only a minor increase in enhancement of HIV infection compared to that obtained with complement alone. Finally, we found evidence of complement-mediated enhancement of HIV infection in resting PBMC. In conclusion, we demonstrated that complement-mediated enhancement of HIV infection does occur in vitro in PBMC.  相似文献   
7.
We experienced that therapeutic embolization of a large cerebral arteriovenous malformation (AVM) led to venous outflow obstruction resulting in intracranial hypertension in a patient who had undergone external decompression. To evaluate hemodynamic changes after embolization, we monitored the cerebrospinal fluid pressure in the next four patients who underwent endovascular treatment. The embolization of a medium AVM resulted in a slight increase in the cerebrospinal fluid pressure. In two medium AVMs, embolization produced slight decreases in the cerebrospinal fluid pressure. In a small AVM, we did not observe any changes in the cerebrospinal fluid pressure during the endovascular treatment. We discuss the mechanism of changes in the intracranial pressure after embolization and conclude that monitoring of the cerebrospinal fluid pressure immediately yields useful information for hemodynamic changes during endovascular treatment.  相似文献   
8.
In infants and children requiring prolonged, multiple central venous (CV) catheterizations, the superior (SVC) and inferior vena cava may become thrombosed or stenotic, making CV access a difficult problem. Use of the iliac vein may be an acceptable alternative. We report a patient with thrombosis of the SVC in whom the external iliac vein was accessed through a retroperitoneal approach for placement of an implantable port. This technique is easy to perform, and there are no special materials or patient positioning required.  相似文献   
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Multisensory scientific data sensualization methods that utilize virtual reality technology permit the use of several human sensations, such as visual, acoustic, and tactile sensation to display numerical data. The purposes of multisensory data sensualization can be classified as follows: (a) representing the relationships between different kinds of data; (b) displaying data utilizing sensory integration; and (c) representing conditions using the compound image. By using multisensory information, computers increase the ability to express data. However, these methods lead us to the question of which sensation should be used to display data most effectively. In this study, a multisensory data sensualization environment was developed in which color, loudness, sound frequency, and air flow pressure could be used to display scientific data. In particular, a wind sensation display prototype using air flow pressure was developed to generate tactile sensation. A basic experiment was conducted on sensory interference when subjects used two kinds of sensations simultaneously. From these results, guidelines for the usage of multisensory information for each purpose is proposed.  相似文献   
10.
A 42-year-old man who complained progressive enlargement of an intrascrotal mass visited to our hospital. Preoperative sonography revealed multiple cystic masses adjacent to the left testis. Total surgical excision was performed. The cystic masses were arising from tunica vaginalis testis. Histopathologically, a cystic lymphangioma was diagnosed because of the morphological features and the immunohistochemical stainings of CD34 and Factor VIII related antigen which were observed positive reactions in endothelial cells of the cysts.  相似文献   
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