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31.
Tenascin-C is an extracellular matrix component which is transiently expressed in association with epithelial cell detachment, proliferation, and migration. This molecule has been identified in respiratory tissue, but little is known about the cellular source of tenascin-C or the factors that regulate its production. Since air pollutants are known to disrupt epithelial integrity, we investigated the regulation of tenascin-C in response to 0.3 ppm ozone in differentiated primate nasal epithelial cells in culture at an air-medium interface. The expression of tenascin-C was upregulated in response to ozone, as determined by Northern blot analysis, Western blotting, and immunofluorescent staining. In contrast, there was no change in the mRNA levels for versican, biglycan, perlecan, or collagen type I. Reduced cellular attachment to the substrate was evident in ozone-treated cultures in association with tenascin-C deposition at the interfaces between cells and basal surfaces. The presence of tenascin-C on denuded areas of the matrix suggests that tenascin-C may have been instrumental in the loss of patches of cells. The modulation of tenascin-C synthesis and distribution may play a significant role in the response of respiratory epithelial cells to ozone exposure.  相似文献   
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Heat insulating and acoustic absorbing materials were endued with fireproof performance and subjected to quantitative evaluations assuming a variety of uses and situations. Fireproofing was performed by spraying an aqueous solution of flame retardants on raw materials (wood shavings, kenaf bast fibers, and core-sheath-type fibers) during the fiber spreading and mixing step. It was possible to treat the materials homogeneously and without increasing manufacturing workload. Flame retardancy was evaluated using vertical flame testing, horizontal flame testing, the 45° Meckel’s Burner method, and a cone calorimetry method in accordance with UL94, JIS D 1201, JIS L 1091, and JIS A 9521, respectively. It was possible to achieve results that satisfied each of these standards, along with quantifying the relations between treatment conditions and performance.  相似文献   
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A multichannel queueing system with ordered entry and no waiting line is considered under the assumption of Poisson arrival and negative exponential service with a different rate in each channel. For the system with two or three heterogeneous servers, the best servers' arrangement is established by interchanging the order of servers to decrease the overflow probability and thereby increase the number of items serviced per unit time. The system considered is a simplified model for a production system with a closed loop conveyor.  相似文献   
34.
Abstract— From the adsorption and desorption characteristics of water, we showed that water can intercalate into BaMgAl10O17: Eu2+ blue phosphor. ESR, XANES, and XPS analyses confirmed that oxidation by water causes thermal degradation of BAM. We also demonstrated that intercalated water accelerates luminance degradation under VUV irradiation and showed oxidation of Eu2+ during panel operation by means of μ‐XPS. We concluded that the cause of thermal and operating degradation of BAM is the oxidation of Eu2+ due to water.  相似文献   
35.
For quantitative determination of 5 triterpenoid constituents, including one ganoderma alcohol (ganodermatriol) and four ganoderma acids (ganoderic acid TR, DM, A, and D), in the products of Ganoderma lucidum, an analytical system was developed using high-performance liquid chromatography. The mobile phase was a linear gradient of 2% AcOH/H2O–CH3CN, and the elution profile was monitored at 243 and 252 nm for ganoderma alcohols and acids, respectively. This system was applied to a quantitative determination of the constituents in the different stage of G. lucidum (BMC9049 strain). The analytical results indicated that the quantity and composition of these triterpenoids differed appreciably among various stages. The stage that showed the highest concentration of ganoderic acid DM and TR also showed the strongest 5α-reductase inhibitory activity. This stage (stage 5 of 6) is thus the prime stage for harvesting this strain. Further, the contents of 5α-reductase inhibitors such as ganoderic acid TR and DM in G. lucidum extracts could be a very useful indicator to assess their 5α-reductase inhibitory activity and verify their potency.  相似文献   
36.
A high amount of zinc disposed in the landfill sites as a mixed-metal plating sludge represents a valuable zinc source. To recover zinc from the plating sludge, a sulfidation treatment is proposed in this study, while it is assumed that ZnS formed could be separated by flotation. The sulfidation treatment was conducted by contacting simulated zinc plating sludge with Na(2)S solution at S(2-) to Zn(2+) molar ratio of 1.5 for a period of 1-48 h, while changing the solid to liquid (S:L) ratio from 0.25:50 to 1.00:50. The conversion of zinc compounds to ZnS was determined based on the consumption of sulfide ions. The reaction products formed by the sulfidation of zinc were identified by X-ray diffraction (XRD). As a result, it was found that the conversion of zinc compounds to ZnS increased with an increase in S:L ratio. A maximum conversion of 0.809 was obtained at an S:L ratio of 1.00:50 after 48 h. However, when the zinc sludge treated at S:L ratio of 1.00:50 for 48 h was subjected to XRD analyses, only ZnS was identified in the treated zinc sludge. The result suggested that the rest of zinc sludge remained unreacted inside the agglomerates of ZnS. The formation behavior of ZnS was predicted by Elovich equation, which was found to describe the system satisfactorily indicating the heterogeneous nature of the sludge.  相似文献   
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Higher accuracy and more efficient production of large aperture glass lenses is increasingly required for high-resolution imaging devices. These glass lenses are typically manufactured by both ultra-precision grinding and polishing. However, prolonged polishing deteriorates the lens shape accuracy and diminishes productivity. In order to reduce the required amount of polishing or even obtain a polish-free fine surface, chemical action-assisted ultra-precision grinding using La-doped CeO2 slurry is proposed and its effectiveness is experimentally evaluated. The results show that the proposed grinding method successfully provides a high-quality surface comparable to a polished surface and results in five times higher productively than conventional grinding.  相似文献   
40.
A polysaccharide was extracted with hot HCl from the endocarp of Citrus depressa grown in Okinawa, Japan. The yield was 4.1% on a fresh weight basis. Composition of the polysaccharide was 89.3% total carbohydrate, 79.2% uronic acid, 4.1% ash and 8.8% moisture. The degree of methoxylation was estimated to be 66.2%. The polysaccharide was composed of d-GalA, d-Gal, l-Ara and l-Rha in the ratio of 100:10.3:1.53:0.94, respectively. The molecular mass was estimated to be approximately 4.1 × 104. NMR spectra indicated that the polysaccharide was mainly composed of (1→4)-linked α-d-GalA and (1→4)-linked β-d-Gal. Methylation analysis results identified 1→2 and 1→2,4 linked Rha, 1→4, 1→3, 1→6 and 1→3,6 linked Gal. The results indicated that the polysaccharide was a pectin, which was relatively simpler than other pectins. The polysaccharide was classified as high-methoxyl pectin. The pectin turned into a gel by the generalised method.  相似文献   
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