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1.
Titanium dioxide (TiO2) nanopowder (P-25;Degussa AG) was treated using dielectric barrier discharge (DBD) in a rotary electrode DBD (RE-DBD) reactor.Its electrical and optical characteristics were investigated during RE-DBD generation.The treated TiO2 nanopowder properties and structures were analyzed using x-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR).After RE-DBD treatment,XRD measurements indicated that the anatase peak theta positions shifted from 25.3° to 25.1°,which can be attributed to the substitution of new functional groups in the TiO2 lattice.The FTIR results show that hydroxyl groups (OH) at 3400 cm-1 increased considerably.The mechanism used to modify the TiO2 nanopowder surface by air DBD treatment was confirmed from optical emission spectrum measurements.Reactive species,such as OH radical,ozone and atomic oxygen can play key roles in hydroxyl formation on the TiO2 nanopowder surface.  相似文献   
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We investigated the prevalence of Salmonella in chicken meat from northern, central, and southern Japan. Between 2006 and 2008, 821 samples from these three regions were collected and examined. Salmonella isolates were detected in 164 (20.0%) of these samples, with 15 (10.0%) of 150, 113 (27.5%) of 411, and 36 (13.8%) of 260 recovered from the northern, central, and southern regions, respectively. We recovered 452 Salmonella isolates. From the isolates, 27 serovars were identified; the predominant serovars isolated were Salmonella Infantis (n=81), Salmonella Kalamu (n=56), and Salmonella Schwarzengrund (n=43). Of the 452 isolates, 443 (98.0%) were resistant to one or more antibiotics, and 221 (48.9%) showed multiple-antibiotic resistance, thereby implying that multiple-antibiotic resistant Salmonella organisms are widespread in chicken meat in Japan. Resistance to oxytetracycline was most common (72.6%), followed by dihydrostreptomycin (69.2%) and bicozamycin (49.1%). This study, the first to report Salmonella prevalence in chicken meat throughout Japan, could provide valuable data for monitoring and controlling Salmonella infection in the future.  相似文献   
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The hypocholesterolemic efficacies of various polyunsaturated fatty acids were compared in rats given cholesterol-enriched diets.Oenothera biennis Linn oil (OBLO, linoleic +γ-linolenic), sunflower oil (linoleic), palm oil (PLO, oleic+linoleic), soybean oil (linoleic+α-linolenic), high-oleic safflower oil (oleic+linoleic), or mixed oil (linoleic+α-linolenic) was added to the diet at 200 g/kg (20% groups). OBLO was also added at 100 g/kg diet (10% group). The serum total and very low density lipoprotein+intermediate lipoprotein+low density lipoprotein cholesterol concentrations of the 10 and 20% OBLO groups were consistently lower than those in the other groups. The liver cholesterol concentration in the PLO group was lower in all groups. The liver cholesterol concentrations in the 10 and 20% OBLO groups were also lower than in the other groups. There were no significant differences in the fecal neutral sterol and bile acid extraction among groups.  相似文献   
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Long-term storage of dessert grapes requires fruit which is free from rotting, efficient means of rapid cooling and cold storage, prompt initial fumigation with sulphur dioxide, and periodic disinfection with the correct dosage, uniformly distributed.The distribution of gas in the cold store or in the transport vehicle depends on the type of package used, the tightness of the pack, the use of pallets, and of course, on the system of air circulation employed. All these factors are very important in the control of deterioration, free from risk of damage due to exposure to excessive concentrations of SO2. Fumigation of packaged produce with diverse mixtures of sodium or potassium bisulphite gives further protection to fruit in transit for more than ten days.  相似文献   
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Nanohole‐structured single‐crystalline Pt nanosheets have been synthesized by the borohydride reduction of Na2PtCl6 confined to the lyotropic liquid crystals (LLCs) of polyoxyethylene (20) sorbitan monooleate (Tween 80) with or without nonaethylene‐glycol (C12EO9). The Pt nanosheets of around 4–10 nm in central thickness and up to 500 nm or above in diameter have a number of hexagonal‐shaped nanoholes ∼1.8 nm wide. High‐resolution electron microscope images of the nanosheets showed atomic fringes with a spacing of 0.22 nm indicating that the nanosheets are crystallographically continuous through the nanoholed and non‐holed areas. The inner‐angle distributions for the hexagonal nanoholes indicate that the six sides of the nanoholes are walled with each two Pt (111), Pt (1 1) and Pt (010) planes. The formation mechanism of nanoholed Pt nanosheets is discussed on the basis of structural and compositional data for the resulting solids and their precursory LLCs, with the aid of similar nanohole growth observed for a Tween 80 free but oleic acid‐incorporated system. It is also demonstrated that the nanoholed Pt nanostructures loaded on carbon exhibit fairly high electrocatalytic activity for oxygen reduction reaction and a high performance as a cathode material for polymer‐electrolyte fuel cells, along with their extremely high thermostability revealed through the effect of electron‐irradiation.  相似文献   
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β-Casomorphin-7 (BCM) is a degradation product of β-casein, a milk component, and has been suggested to affect the immune system. However, its effect on mucosal immunity, especially anti-tumor immunity, in cancer-bearing individuals is not clear. We investigated the effects of BCM on lymphocytes using an in vitro system comprising mouse splenocytes, a mouse colorectal carcinogenesis model, and a mouse orthotopic colorectal cancer model. Treatment of mouse splenocytes with BCM in vitro reduced numbers of cluster of differentiation (CD) 20+ B cells, CD4+ T cells, and regulatory T cells (Tregs), and increased CD8+ T cells. Administration of BCM and the CD10 inhibitor thiorphan (TOP) to mice resulted in similar alterations in the lymphocyte subsets in the spleen and intestinal mucosa. BCM was degraded in a concentration- and time-dependent manner by the neutral endopeptidase CD10, and the formed BCM degradation product did not affect the lymphocyte counts. Furthermore, degradation was completely suppressed by TOP. In the azoxymethane mouse colorectal carcinogenesis model, the incidence of aberrant crypt foci, adenoma, and adenocarcinoma was reduced by co-treatment with BCM and TOP. Furthermore, when CT26 mouse colon cancer cells were inoculated into the cecum of syngeneic BALB/c mice and concurrently treated with BCM and TOP, infiltration of CD8+ T cells was promoted, and tumor growth and liver metastasis were suppressed. These results suggest that by suppressing the BCM degradation system, the anti-tumor effect of BCM is enhanced and it can suppress the development and progression of colorectal cancer.  相似文献   
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Platinum/carbon (Pt/C) composite materials were prepared by the hydrazine reduction of H2PtCl6 confined to a mixed surfactant lytropic liquid crystal (LC)/C mixture with varying amounts of water. The reaction at relatively low water contents successfully yielded cross-linked Pt nanowires with wire-widths of 2-5 nm. The novel Pt nanostructure is believed to be from poorly hydrated hexagonal domains formed together with layered domains by the phase separation of the precursory LC mixture in the presence of carbon. Electrochemical measurements using cyclic volutammetry and membrane electrode assemblies revealed that the cross-linked nanowired Pt/C composite exhibits fairly high electrocatalytic activity for oxygen reduction reaction, as well as a high performance as the cathode material for polymer electrolyte fuel cells.  相似文献   
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