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排序方式: 共有1578条查询结果,搜索用时 31 毫秒
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François Chiocchio Geneviève Beaulieu Jean-Sébastien Boudrias Vincent Rousseau Caroline Aubé Estelle M. Morin 《International Journal of Project Management》2010
It is important to understand the extent to which project involvement affects mental health. As projects and project management expand beyond traditional fields, it is also important to compare project involvement and mental health across settings that vary in terms of management structure. This study is the first to validate a Project Involvement Index (PII) useful in various settings to understand how workload relates to mental health defined as high psychological well-being and low psychological distress. Our results demonstrate that the PII is parsimonious measure showing reliability, predictive validity, and discriminant validity. Furthermore, results show that people involved in projects from a non-projectized organization show less mental health than those from a projectized organization. 相似文献
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Núria Parera Pera Dr. Hilbert M. Branderhorst Dr. Raymond Kooij Caroline Maierhofer Dr. Marjolein van der Kaaden Rob M. J. Liskamp Prof. Dr. Valentin Wittmann Prof. Dr. Rob Ruijtenbeek Dr. Roland J. Pieters Dr. 《Chembiochem : a European journal of chemical biology》2010,11(13):1896-1904
Multivalency is an important phenomenon in protein–carbohydrate interactions. In order to evaluate glycodendrimers as multivalent inhibitors of carbohydrate binding proteins, we displayed them on a microarray surface. Valencies were varied from 1 to 8, and corrections were made for the valencies so that all surfaces contained the same amount of the sugar ligand. Five different carbohydrates were attached to the dendrimers. A series of fluorescent lectins was evaluated, and for each of them a binding profile was obtained from a single experiment showing both the specificity of the lectin for a certain sugar and whether it prefers multivalent ligands or not. Very distinct binding patterns were seen for the various lectins. The results were rationalized with respect to the interbinding distances of the lectins. 相似文献
125.
The temperature effects on a ferroelectric non-volatile memory latch were measured. The device is based on a design from Radiant Technologies Inc. utilizing a discrete ferroelectric capacitor. The effects measured include functionality, I-V characteristics and retention. The range of temperatures for which the device was tested is –107°F to +302°F. The results are compared with measurements made at room temperature for the device. Retention measurements of the device at elevated temperatures allow predictions of retention performance under normal operating conditions. Potential applications of this device in harsh environments which include aerospace, industrial and automotive are presented. 相似文献
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Omar S. Ahmed Charles Tardif Caroline Rouger Vessela Atanasova Florence Richard-Forget Pierre Waffo-Téguo 《Comprehensive Reviews in Food Science and Food Safety》2022,21(2):1161-1197
Mycotoxins are metabolites produced by molds that contaminate food commodities, are harmful to both humans and animals, as well as cause economic losses. Many countries have set regulatory limits and strict thresholds to control the level of mycotoxins in food and feedstuffs. New technologies and strategies have been developed to inhibit toxigenic fungal invasion and to decontaminate mycotoxins. However, many of these strategies do not sufficiently detoxify mycotoxins and leave residual toxic by-products. This review focuses on the use of phenolic compounds obtained from botanical extracts as promising bioagents to inhibit fungal growth and/or to limit mycotoxin yields. The mechanism of these botanicals, legislation concerning their use, and their safety are also discussed. In addition, recent strategies to overcome stability and solubility constraints of phenolic compounds to be used in food and feed stuffs are also mentioned. 相似文献
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Jonas Schröter Tobias Graf Daniel Frank Christiane Bauer Josef Kallo Caroline Willich 《International Journal of Hydrogen Energy》2021,46(40):21151-21159
Low ambient pressures at elevated flight altitudes lead to power losses in fuel cell powered aircrafts. As countermeasure ambient air can be pressurized with a suitable fuel cell air supply system. In this study the influence of low ambient pressures and pressure losses within the system on the performance of two turbo compressors and the resulting stack power are examined theoretically and the findings validated experimentally. Results show that decreasing ambient pressures and pressure losses in front and after the compressor reduce the maximum pressure from 2.4 to 1.6 bar(a) in the examined system. Air compression may require a significant share of the fuel cell stack power and the maximum system power is reduced from 54 to 41 kW. For air pressures higher than 1.8 bar(a) the fuel cell stack power gain due to pressurization is found to be cancelled out by the increasing power required for air compression. 相似文献
128.
Caroline A. Harris Mary J. Renfrew Michael W. Woolridge 《Food Additives & Contaminants》2001,18(12):1124-1129
Assessing exposure of consumers to pesticide residues is an area of regulatory science that has rapidly developed over the last decade. From simplistic, deterministic models calculating lifetime exposure for adults only, assessment procedures have diversified so that more realistic estimates of long term exposures for adults, schoolchildren, toddlers and infants and short term exposures for adults and toddlers (who generally bound the more extreme consumer patterns) are now carried out. The final assessment of risk still remains a simplistic numeric comparison against hazard assessment based on a wide range of toxicity studies incorporating the appropriate safety or uncertainty factors. As development of risk assessments continues, the use of probabilistic models is becoming an invaluable information tool for quantitative risk management and aiding assessment of cumulative exposure. This paper examines the recent developments in risk assessment and consumer perception of the risks of pesticide residues, and speculates where the future developments in these areas may lie. 相似文献
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