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21.
Guided by self‐determination theory, the aim of this study was to examine whether adolescents’ autonomous motivation for making healthy diet choices mediates the association between parenting practices regarding diet and adolescent food choices. We analyzed data from the NCI FLASHE study, a survey of demographically diverse parents and their adolescent children (N = 1,646 dyads). Path models supported self‐determination theory’s assertion that indirect, encouraging parenting practices fostered internal motivation; in contrast, regulation was both positively and negatively linked to motivation depending on the model. Models also yielded direct paths between parenting practices and healthy and unhealthy diet choices. Overall, regardless of what predicted motivation, adolescents’ autonomous motivation was linked with their consumption of healthier foods and drinks. As such, cultivating a sense of internal motivation during these formative years may put young people on a path toward healthy patterns of self‐regulation later in life.  相似文献   
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Operations management methods have been applied profitably to a wide range of technology portfolio management problems, but have been slow to be adopted by governments and policy makers. We develop a framework that allows us to apply such techniques to a large and important public policy problem: energy technology R&D portfolio management under climate change. We apply a multi‐model approach, implementing probabilistic data derived from expert elicitations into a novel stochastic programming version of a dynamic integrated assessment model. We note that while the unifying framework we present can be applied to a range of models and data sets, the specific results depend on the data and assumptions used and therefore may not be generalizable. Nevertheless, the results are suggestive, and we find that the optimal technology portfolio for the set of projects considered is fairly robust to different specifications of climate uncertainty, to different policy environments, and to assumptions about the opportunity cost of investing. We also conclude that policy makers would do better to over‐invest in R&D rather than under‐invest. Finally, we show that R&D can play different roles in different types of policy environments, sometimes leading primarily to cost reduction, other times leading to better environmental outcomes.  相似文献   
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Today there are more than 80,000 chemicals in commerce and the environment. The potential human health risks are unknown for the vast majority of these chemicals as they lack human health risk assessments, toxicity reference values, and risk screening values. We aim to use computational toxicology and quantitative high‐throughput screening (qHTS) technologies to fill these data gaps, and begin to prioritize these chemicals for additional assessment. In this pilot, we demonstrate how we were able to identify that benzo[k]fluoranthene may induce DNA damage and steatosis using qHTS data and two separate adverse outcome pathways (AOPs). We also demonstrate how bootstrap natural spline‐based meta‐regression can be used to integrate data across multiple assay replicates to generate a concentration–response curve. We used this analysis to calculate an in vitro point of departure of 0.751 μM and risk‐specific in vitro concentrations of 0.29 μM and 0.28 μM for 1:1,000 and 1:10,000 risk, respectively, for DNA damage. Based on the available evidence, and considering that only a single HSD17B4 assay is available, we have low overall confidence in the steatosis hazard identification. This case study suggests that coupling qHTS assays with AOPs and ontologies will facilitate hazard identification. Combining this with quantitative evidence integration methods, such as bootstrap meta‐regression, may allow risk assessors to identify points of departure and risk‐specific internal/in vitro concentrations. These results are sufficient to prioritize the chemicals; however, in the longer term we will need to estimate external doses for risk screening purposes, such as through margin of exposure methods.  相似文献   
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Over the years, a growing body of evidence indicates that certain cognitive skills are a critical determinant of leader performance. In the present effort we show that application of these skills is typically founded in case-based knowledge. Subsequently, we identify nine key skills people in leadership positions employ when working with case-based knowledge to address leadership problems: 1) problem definition, 2) cause/goal analysis, 3) constraint analysis, 4) planning, 5) forecasting, 6) creative thinking, 7) idea evaluation, 8) wisdom, and 9) sensemaking/visioning. Individual and situational contingencies shaping effective application of these thinking skills is discussed. In addition, the implications of findings bearing on leader thinking skills for leader assessment and leader development are considered.  相似文献   
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In any crisis, there is a great deal of uncertainty, often geographical uncertainty or, more precisely, spatiotemporal uncertainty. Examples include the spread of contamination from an industrial accident, drifting volcanic ash, and the path of a hurricane. Estimating spatiotemporal probabilities is usually a difficult task, but that is not our primary concern. Rather, we ask how analysts can communicate spatiotemporal uncertainty to those handling the crisis. We comment on the somewhat limited literature on the representation of spatial uncertainty on maps. We note that many cognitive issues arise and that the potential for confusion is high. We note that in the early stages of handling a crisis, the uncertainties involved may be deep, i.e., difficult or impossible to quantify in the time available. In such circumstance, we suggest the idea of presenting multiple scenarios.  相似文献   
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Historically the law regarded children as inherently unreliable and made it difficult for them to testify. Since 1975 awareness of child abuse has increased and research has established that children can be reliable witnesses. Governments began to recognize the needs and capacities of children and enacted legal reforms to facilitate prosecutions for child abuse. This paper reports on a survey of victim witness workers and other justice system professionals which reveals some of the continuedfailings of that system in dealing with children. Althoughrelatively rare, there are cases of false allegations of abuse, usually a result of investigations by poorly trained professionals. Further legal reforms and better human supports are required to ensure that the needs of children are met and their capacities as witnesses are fully appreciated.  相似文献   
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ABSTRACT

Illegitimate tasks are tasks that violate norms for what the employee should do as part of the job, and have been found to harm employees’ well-being. The current research uses a mixed methods design to examine the role of attributions on the two types of illegitimate tasks: unreasonable and unnecessary tasks. A sample of 432 engineers described a specific illegitimate task that was assigned to them, the attributions they made and their response. They also completed a quantitative questionnaire. Results from both the qualitative (event level) and quantitative (person level) portions of our study portray differences in the attributions made to unreasonable and unnecessary tasks, as well as differential negative effects on employees’ emotions. In addition, hostile attribution bias was found to moderate the relationship between illegitimate tasks and negative emotions, particularly for unreasonable tasks. This supports the theoretical basis for illegitimate tasks because unreasonable tasks pose a potentially greater risk to the employee’s self-worth than unnecessary tasks that are more often assigned at random.  相似文献   
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