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排序方式: 共有636条查询结果,搜索用时 78 毫秒
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Onay B. Dogan Makenzie G. Flach Markus F. Miller Mindy M. Brashears 《Comprehensive Reviews in Food Science and Food Safety》2023,22(5):3506-3530
Recently, multiple reports from regulatory agencies have linked leafy green outbreaks to nearby or adjacent cattle operations. While they have made logical explanations for this phenomenon, the reports and data should be summarized to determine if the association was based on empirical data, epidemiological association, or speculation. Therefore, this scoping review aims to gather data on the mechanisms of transmission for pathogens from livestock to produce, identify if direct evidence linking the two entities exists, and identify any knowledge gaps in the scientific literature and public health reports. Eight databases were searched systematically and 27 eligible primary research products, which focus on produce safety concerning proximity to livestock, provided empirical or epidemiological association and described mechanisms of transmission, qualitatively or quantitatively were retained. Fifteen public health reports were also covered. Results from the scientific articles provided evidence that proximity to livestock might be a risk factor; however, most lack quantitative data on the relative contribution of different pathways for contamination. Public health reports mainly indicate livestock presence as a possible source and encourage further research. Although the collected information regarding the proximity of cattle is a concern, data gaps indicate that more studies should be conducted to determine the relative contribution of different mechanisms of contamination and generate quantitative data to inform food safety risk analyses, regarding leafy greens produced nearby livestock areas. 相似文献
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Alan Devoe Hung Trinh Fatih Dogan 《International Journal of Applied Ceramic Technology》2023,20(5):3140-3147
The electrical properties of dense, high purity CaZrO3 discs, sintered at 1380°C with and without added ZrO2, were investigated up to 950°C. Dielectric constant, loss tangent, and electrical conductivity were measured from 25 to 725°C, and the real and imaginary impedances were measured between 800 and 950°C by impedance spectroscopy techniques. Dielectric constant increased by 8% above 300°C and loss tangent increased from .1% at 25°C to ∼2% above 300°C. Activation energy of electrical conductivity determined between 300°C and 950°C by alternative current (AC) and direct current (DC) measurements. These results indicate that CaZrO3 could be a useful dielectric material for capacitor applications up to 500°C. A reported decrease in conductivity due to addition of excess ZrO2 into stoichiometric CaZrO3 could not be confirmed. 相似文献
636.
Dong Wook Kim Yuki Hagiwara Shodai Hasebe Nihal Olcay Dogan Mingchao Zhang Toru Asahi Hideko Koshima Metin Sitti 《Advanced functional materials》2023,33(47):2305916
Research on molecular crystals exhibiting light-driven actuation has made remarkable progress through the development of various molecules and the identification of driving mechanisms. However, crystals developed to date have been driven mainly by ultraviolet (UV) or blue light irradiation, and driving by red or near-infrared (NIR) light has not been attempted yet. Herein, a broad-wavelength light-driven molecular crystals that exhibit high-speed bending by photothermal effect is developed. Titanium carbide (Ti3C2Tx) MXene nanosheets are integrated into salicylideneaniline crystals to extend the wavelength range that causes photothermally driven bending to UV, visible, and NIR light. In addition, unlike the thin pristine molecular crystals that show slow photoisomerization-induced bending only under UV light, the MXene layer enables the molecular crystals to be actuated rapidly regardless of their thickness over a wide range of wavelengths. The hybridization of molecular crystals with MXene, which exhibits strong biocompatibility as well as NIR light-driven photothermal effect, allows for the bending of the hybrid crystals inside agar phantoms mimicking biological tissue. Last, it is confirmed that MXene hybridization can be extended to common molecular crystals including various salicylideneaniline and anisole derivatives. 相似文献