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21.
The best methods for determining surface roughness in an industrial environment are of the noncontact variety, with reproduction of the profile. The objective of this work was to compare the roughness profile obtained by a contact stylus with a commercial laser displacement sensor (LDS). Measurements were done using 15 wood species with different densities and colors, based on which special triangle profiles were prepared. The accuracy of the laser sensor was examined by statistical analysis of roughness parameters measured from the profiles. Experimental results show that LDS profiles were imitated correctly. However, LDS accuracy depends on the scanned wood properties (density and color), installation position of the sensor, and profile shape. It was found that evaluation of dark and high-density wooden surfaces was imperfect.Part of this work was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, April 2000; and at the 51st Annual Meeting of the Japan Wood Research Society, Tokyo, April 2001  相似文献   
22.
We examined the abrasive wear properties and the effect of abrasive grain size on the rate of wear when sugi wood (Cryptomeria japonica D.Don), compressed to various densities, was rubbed with abrasive paper. The results showed that the wear resistance of compressed wood increased linearly with the increased compression ratio; and under the condition of a low compression ratio it tended to be higher in comparison with the strength of compressed wood. The critical grain size effect, which can be witnessed during the abrasive wear of metals and plastics, was seen when low pressure was applied to the abrasive material. At higher pressures, the wear rate of the compressed wood increased with grain size, but the critical grain size effect was not observed. The pressure required to create the critical grain size effect was found to be higher than that needed for other types of uncompressed wood with the same yield properties.Part of this report was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, April 2000  相似文献   
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Cytotoxic T-lymphocyte (CTL) responses to hemagglutinin (H) protein of canine distemper virus (CDV) were evaluated in dogs using the replication-deficient adenovirus protein expression system. Skin fibroblasts were isolated from two dogs and were infected with recombinant adenovirus bearing the CDV-H gene (Ade-CDVH). CTL assay was performed using fibroblasts expressing CDV-H protein as target cells and peripheral blood lymphocytes (PBL) collected from the same dogs one week after immunization of CDV as effector cells. Specific cytotoxic activity was observed against autologous but not heterologous fibroblasts expressing CDV-H protein. These results indicate that the CTL epitope(s) were localized in the H protein.  相似文献   
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Clearance of Theileria sergenti-infected bovine red blood cells (Bo-RBCs) from the blood circulation of severe combined immune deficiency (SCID) mice was studied to help understand the mechanisms of anemia developing in cattle infected with T. sergenti. For the clearance test, Bo-RBC samples having 2%, 58%, and 76% parasitemia and, as a control, parasite-free Bo-RBCs were prepared in the Bo-RBC-SCID mouse model. The T. sergenti-infected Bo-RBCs and the uninfected control Bo-RBCs were separately labeled with two, green and red, fluorescent dyes, mixed together, and injected intravenously into SCID mice. The blood samples collected at various time points were observed under a fluorescent microscope, and the numbers of green and red fluorescing RBCs were counted differentially to determine the clearance rates of T. sergenti-infected and uninfected Bo-RBCs. This test clearly demonstrated that the Bo-RBC samples having higher parasitemias were cleared faster from the blood circulation of SCID mice. The results suggest that the intravascular clearance system in SCID mice may have a mechanism by which T. sergenti-parasitized and non-parasitized Bo-RBCs are recognized and cleared differentially.  相似文献   
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Pigmentation enhancement in cultured red sea bream, Chrysophrys major, was investigated using Antarctic krill, Euphausia superba, and a mysid, Neomysis sp., as a source of astaxanthin. Diets fortified with processed Antarctic krill (krill meal) and its acetone extract, containing 0.82–4.92 mg carotenoids/100 g dry weight, and raw krill and raw mysid supplemented diets, containing about 2.00 mg carotenoids/100 g wet weight, were formulated and tested for carotenoid deposition. The rate of carotenoid deposition in fish fed with raw krill and raw mysid was significantly higher and resulted in distinct pigmentation. The groups fed with the krill meal and acetone extract diets showed varied concentrations of skin carotenoids and resulted in faint pigmentation. Pigmented fish then fed on a carotenoid-free diet for the same length of time showed no apparent differences in the skin pigmentation although the detectable amounts of carotenoids varied. The bream converted some of the dietary astaxanthin to skin tunaxanthin.  相似文献   
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Highly pathogenic avian influenza virus (HPAIV) induces acute disease in chickens causing high mortality and morbidity and is a major threat to poultry industries in Southeast Asian countries. The mechanisms of disease manifestation and host innate immune responses against HAPIV in chickens are not well understood. In this study, we examined virus replication and host gene expressions in four chicken cell lines in vitro to elucidate the impact of host innate immune responses against viral replication. It was demonstrated that viral replication efficiencies were different depending on the cell line. The viral replication appeared to be affected by the basal expression of IFN related genes. The expression of immune-related genes against the viral infection also varied in a cell line dependent manner. In non-immune derived cell lines, but not in immune derived cell lines, the expression of the CCL5 and CCL20 genes were induced by HPAIV infection. Reverse genetics HPAIV, with internal genes from avirulent avian influenza, reduced virus replication and affected immune-related gene expression in a cell line dependent manner. These results suggest the possibility that differential immune responses in different cell types in local tissues could modulate the consequences of HPAIV infection in chickens.  相似文献   
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