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21.
The antimicrobial effects of spices and herbs from 18 plant species were examined on a foodborne pathogen, Vibrio parahaemolyticus, with the use of combinations of temperatures and nutrient levels. Basil, clove, garlic, horseradish, marjoram, oregano, rosemary, and thyme exhibited antibacterial activities at incubation of 30 degrees C, while with the exception of horseradish, the same spices and additional 7 species exhibited the activities at 5 degrees C. The lowest MIC (minimum inhibitory concentration) was 0.125% observed in clove and marjoram at 30 degrees C in a nutrient rich medium. Lowering of incubation temperature produced little effect on the MICs except for turmeric. The decreasing of the MIC in turmeric appeared to be basically attributed to the sensitivity of the bacterium to coldness. In nutrient poor medium, the lowest was 0.001 and 0.00025% in marjoram at 30 degrees C and at 5 degrees C, respectively. The sensitivity to several spices and herbs was similar among different clinical serotypes including the emerging strain O3:K6. These results suggest that the spices and herbs can be practical for protecting seafood from the risk of contamination by V. parahaemolyticus and used in hurdle technology with low temperature.  相似文献   
22.
In Laos, located in mainland Southeast Asia, shifting cultivation has been one of the important means of livelihood, in terms of food security as well as religious and cultural anchorage, for local communities in a number of areas, especially in upland areas in the country. In Pakbeng District, Oudomxay Province, northern Laos, due to the implementation of various land and forest management policies and a village relocation and consolidation program, local communities were restricted from access to the forests and faced a shortage of agricultural lands. After facing difficulties in securing sufficient lands, the local farmers used the forests in a destructive manner. The author of this article was engaged with the Community-based Watershed Management Project, as a program director of an environmental NGO and tackled challenges to achieve a land and forest management system suitable for land use by local communities. The NGO attempted to apply an alternative approach to incorporate swidden farmers’ land use system into official land and forest management institutions.  相似文献   
23.
Although a high-energy gamma camera can obtain images of 137Cs distribution by detecting the 662-keV gamma photons, its spatial resolution is reduced because high-energy gamma photons penetrate the edge of the pinhole collimator. To solve this problem, we developed a low-energy X-ray camera that detects the characteristic X-ray photons (32–37 keV) that are emitted from 137Cs to obtain high resolution images. We used a 45 × 45 × 1-mm-thick NaI(Tl) scintillator that was encapsulated in 0.1-mm-thick aluminum and optically coupled to a 2-inch square, position sensitive photomultiplier tube (Hamamatsu Photonics, PSPMT:H12700 MOD) as an imaging detector. The imaging detector was encased in a 2-cm-thick tungsten alloy container and a pinhole collimator was attached to its camera head. The spatial resolution and sensitivity were ~5 mm full-width at half-maximum and ~0.6 cps/MBq for the 1.5-mm pinhole collimator 10 cm from the collimator surface, respectively. We administered 5 MBq of 137Cs to a soybean seedling, imaged the distribution of radionuclides for six hours, and successfully obtained a high resolution image of it with our developed X-ray camera. We believe our camera will be a powerful tool for such 137Cs imaging in plants.  相似文献   
24.
Metal surfaces can be improved in terms of thermal, mechanical, and chemical properties by a ceramic coating. The chromium-free corrosion resistance of stainless steel was achieved using a chemical solution method. Precursor solutions were prepared from metal alkoxides and were deposited on stainless-steel surfaces by dip coating and heat-treating at temperatures <500°C. The stainless steel was coated by silica, zirconia, and titania single-layer coating films, and/or coated by silica/zirconia and silica/titania double-layer coating films. The corrosion resistance was improved remarkably by a submicrometer silica-based coating on the stainless steel.  相似文献   
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26.
Multidrug resistance (MDR) is considered to be an important impediment to the effective treatment of cancer. P-glycoprotein, the drug efflux pump that mediates this resistance, can be inhibited by a wide variety of pharmacological agents, resulting in the circumvention of the MDR phenotype. SDZ PSC 833 ([3'-keto-Bmt1]-Val2]-cyclosporine), a nonimmunosuppressive cyclosporine D derivative, was identified to be a potent MDR modulator (Gaveriaux et al. J. Cell Pharmacol. 2:225-234; 1991). In this study, the interactions of P-glycoprotein with two cyclosporine derivatives, SDZ PSC 833 and cyclosporine A (CsA, Sandimmune), were analyzed. SDZ PSC 833 enhanced the sensitivity of the MDR cells to anticancer drugs by increasing the accumulation and inhibiting the efflux of cytotoxic agents from resistant cells more efficiently than CsA. The two cyclosporine analogs competed with the labeling of P-glycoprotein by a photoactive cyclosporine derivative. In addition, membrane vesicles derived from resistant cells bound SDZ PSC 833. However, CsA was transported by P-glycoprotein, whereas SDZ PSC 833 was not actively transported. This resulted in a prolonged inhibitory effect by SDZ PSC 833. The studies suggest that the binding of SDZ PSC 833 to P-glycoprotein in the absence of its transport from MDR cells mediated its high potency as an MDR reversing agent. In addition, the comparison of the two cyclosporine analogs indicated that limited chemical modifications of MDR reversing agents can affect their potential to inhibit P-glycoprotein function.  相似文献   
27.
In this study, the effect of dietary calcium and vitamin D on serum parathyroid hormone and vitamin D metabolites was measured in 376 free-living women aged 65-77 y. Mean calcium intake in both groups was close to the recommended dietary allowance of 800 mg/d. Mean vitamin D intake in the 245 women not taking vitamin D supplements was 3.53 microg/d (141 IU/d), which is below the recommended dietary allowance of 5 microg/d (200 IU/d). To test the hypothesis that vitamin D is more important than calcium in reducing serum parathyroid hormone, the source of dietary calcium intake was subdivided into milk, which is fortified with vitamin D, and nonmilk sources. The serum parathyroid hormone concentration was inversely correlated with calcium intake derived from milk (r = -0.20, P < 0.01) but not from nonmilk sources (r = -0.06). Furthermore, serum calcidiol correlated with milk calcium intake (r = 0.35, P < 0.001) but not with nonmilk calcium intake (r = 0.10). Multivariate analysis showed a significant effect of season on serum calcidiol but not on serum parathyroid hormone. Serum parathyroid hormone was inversely correlated with serum calcidiol (r = -0.33, P < 0.001) and the regression predicted that mean serum parathyroid hormone would be reduced in the elderly to concentrations considered normal in the young when serum calcidiol is 122 nmol/L (49 ng/mL); this would require a much higher recommended dietary allowance for vitamin D than 5 microg/d (200 IU/d).  相似文献   
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29.
Emulsion polymerization of methyl methacrylate was carried out using a mixture of anionic emulsifier, sodium dodecyl sulfate (SDS) and nonionic emulsifier, poly(oxy ethylene) nonyl phenyl ether with an average of 40 oxy ethylene units per molecule (NP-40). The rate of polymerization and the number of polymer particles produced both increased with increasing the amount of NP-40 initially charged, when NP-40 was used as the sole emulsifier. Interestingly, however, both the rate of polymerization and the number of polymer particles produced was found to decrease, when the amount of NP-40 added to the fixed amount of SDS is increased in the mixed emulsifier. On the contrary, they both increased when the amount of SDS added to the fixed amount of NP-40 is increased in the mixed emulsifier. The mixed emulsifier did not affect the number of the radicals per polymer particle at a certain number of polymer particles, but affected the number of polymer particles, thus the rate of polymerization.  相似文献   
30.
A cylindrical linear pulse motor (CLPM) of a new construction is proposed in this paper. The conventional CLPM, which has a permanent magnet between A-phase and B-phase stators, has a problem: thrust unbalance occurs because the magnetic flux of the outer poles is longer than that of the inner poles. This paper proposes a CLPM of completely new construction, in which the field magnetic flux and the armature magnetic flux perpendicularly intersect each other as a result of a restructured magnetic circuit. This new CLPM has the same magnetic field as the stepping motor, and has the distinctive characteristic of being available in a multiphase design, as well as the conventional two-phase design. A five-phase 10-pole CLPM was experimentally manufactured and the static thrust was measured to identify its basic characteristics. The experiment confirmed the theory that the torque did not differ from phase to phase and that controllability equal to that of the stepping motor was obtainable. The CLPM proposed here is effective as an alternate linear electromagnetic actuator for electrical servos of air actuators (such as air cylinders).  相似文献   
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