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141.
White JB Beckford J Yadegarynia S Ngo N Lialiutska T d'Alarcao M 《Food chemistry》2012,131(4):1453-1459
A common feature of both apoptosis and inflammation is the activation of caspases. Caspases are aspartate-directed cysteine proteases that have numerous cellular targets. It has been discovered that several flavonoids are inhibitors of caspases. Flavonoids are members of a family of polyphenolic compounds from plants that have many biological properties, one of which is the ability to induce cell death. Some flavonoids are selective inhibitors of particular caspases. Since some of the inhibitory flavonoids are nevertheless cytotoxic, these results suggest that flavonoid-induced cell death may be occurring through a non-classical apoptosis pathway that is not dependent on caspase activity. 相似文献
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Marianne Richou Marc Missirlian Nicolas Vignal Vincent Cantone Caroline Hernandez Prachai Norajitra Luigi Spatafora 《Fusion Engineering and Design》2013,88(9-10):1753-1757
Plasma facing components (PFCs) with tungsten (W) armor materials for DEMO divertor require a high heat flux removal capability (at least 10 MW/m2 in steady-state conditions). The reference divertor PFC concept is a finger with a tungsten tile as a protection and sacrificial layer brazed to a thimble made of tungsten alloy W – 1% La2O3 (WL10). Defects may be located at the W thimble to W tile interface. As the number of fingers is considerable (>250,000), it is then a major issue to develop a reliable control procedure in order to control with a non-destructive examination the fabrication processes. The feasibility for detecting defect with infrared thermography SATIR test bed is presented. SATIR is based on the heat transient method and is used as an inspection tool in order to assess component heat transfer capability. SATIR tests were performed on fingers integrating or not the complex He cooling system (steel cartridge with jet holes). Millimeter size artificial defects were manufactured and their detectability was evaluated. Results of this study demonstrate that the SATIR method can be considered as a relevant non-destructive technique examination for the defect detection of DEMO divertor fingers. 相似文献
146.
A review of 15 papers reporting 25 independent correlations of perceived beauty with perceived usability showed a remarkably high variability in the reported coefficients. This may be due to methodological inconsistencies. For example, products are often not selected systematically, and statistical tests are rarely performed to test the generality of findings across products. In addition, studies often restrict themselves to simply reporting correlations without further specification of underlying judgmental processes. The present study's main objective is to re-examine the relation between beauty and usability, that is, the implication that “what is beautiful is usable.” To rectify previous methodological shortcomings, both products and participants were sampled in the same way and the data aggregated both by averaging over participants to assess the covariance across ratings of products and by averaging over products to assess the covariance across participants. In addition, we adopted an inference perspective to qualify underlying processes to examine the possibility that, under the circumstances pertaining in most studies of this kind where participants have limited experience of using a website or product, the relationship between beauty and usability is mediated by goodness. A mediator analysis of the relationship between beauty, the overall evaluation (i.e., “goodness”) and pragmatic quality (as operationalization of usability) suggests that the relationship between beauty and usability has been overplayed as the correlation between pragmatic quality and beauty is wholly mediated by goodness. This pattern of relationships was consistent across four different data sets and different ways of data aggregation. Finally, suggestions are made regarding methodologies that could be used in future studies that build on these results. 相似文献
147.
Glycoalkaloids in potato-derived products result in bitter taste and potentially toxic effects at high intakes. Generally, extraction of glycoalkaloids prior to HPLC analysis is carried out by dilute acetic acid. For most potato-derived extracts including heat-coagulated potato proteins, this extraction method is sufficient to achieve satisfying tri-glycoalkaloid (TGA) recoveries. Soluble potato proteins obtained by non-denaturing processes show different requirements for glycoalkaloid extraction. TGA extraction was optimized for two commercially available native potato protein isolates and compared to heat-coagulated potato protein. The highest TGA levels were determined in the extract when extraction was carried out at 40 °C by at least 5 % acetic or propionic acid supplemented with 20 mM Na-1-heptanesulfonate (HSA). Addition of HSA results in substantially improved TGA extraction and induces precipitation of soluble protein which enhanced sample cleanup. On the contrary, extraction of TGA from coagulated potato protein in the presence of HSA showed a reduced TGA extraction efficiency. This improved TGA extraction procedure for soluble non-denatured potato protein isolates results in reliable quantification of bitter tasting and toxic glycoalkaloid levels. This contributes to a non-bitter and safe use of the nutritional and functional benefits of this plant protein in food applications. 相似文献
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This article reports an extraction–purification of napins from an industrial rapeseed meal and the assessment of their antimicrobial activity against Fusarium langsethiae. The best extraction conditions are observed at pH 2, 12% (w/w) of rapeseed meal after 15 min of extraction in water at room temperature. Under these conditions the extraction is highly selective, allowing a simple purification process (ammonium sulfate precipitation followed by desalting size exclusion chromatography) to get purified napins. These napins possessed significant anti-Fusarium activity (IC50 = 70 μM) and a compact secondary structure rich in α-helix, which may explain this bioactivity. 相似文献
150.
Data warehouses (DW) form the backbone of data integration that is necessary for analytical applications, and play important roles in the information technology landscape of many industries. We introduce an approach for addressing the fundamental problem of semantic heterogeneity in the design of data integration requirements during DW development. In contrast to ontology-driven or schema-matching approaches, which propose the automatic resolution of differences ex-post, our approach addresses the core problem of data integration requirements: understanding and resolving different contextual meanings of data fields. We ground the approach firmly in communication theory and build on practices from agile software development. Besides providing relevant insights for the design of data integration requirements, our findings point to communication theory as a sound underlying foundation for a design theory of information systems development. 相似文献