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131.
132.
Associations between uncoupling protein (UCP) expression and functional changes in myocardial mitochondrial bio-energetics have not been well studied during periods of starvation stress. Our aim was to study the effects of acute starvation, for 24 or 48 h, on combined cardiac mitochondrial function and UCP expression in mice. Isolated heart mitochondria from female mice starved for 48 h compared to that from mice fed revealed a significantly (p < 0.05) decreased adenosine diphosphate-to-oxygen ratio, a significantly increased proton leak and an increased GTP inhibition on palmitic acid-induced state 4 oxygen consumption (p < 0.05). These bio-energetic functional changes were associated with increases in mitochondrial UCP2 and UCP3 protein expression. In conclusion, our findings suggest that increased UCP2 and UCP3 levels may contribute to decreased myocardial mitochondrial bio-energetic function due to starvation.  相似文献   
133.
Recent studies have demonstrated that context can dramatically influence the recognition of basic facial expressions, yet the nature of this phenomenon is largely unknown. In the present paper we begin to characterize the underlying process of face-context integration. Specifically, we examine whether it is a relatively controlled or automatic process. In Experiment 1 participants were motivated and instructed to avoid using the context while categorizing contextualized facial expression, or they were led to believe that the context was irrelevant. Nevertheless, they were unable to disregard the context, which exerted a strong effect on their emotion recognition. In Experiment 2, participants categorized contextualized facial expressions while engaged in a concurrent working memory task. Despite the load, the context exerted a strong influence on their recognition of facial expressions. These results suggest that facial expressions and their body contexts are integrated in an unintentional, uncontrollable, and relatively effortless manner.  相似文献   
134.
Use of unmanned aerial vehicles (UAVs) is an increasingly important element of military missions. However, controlling UAVs may impose high stress and workload on the operator. This study evaluated the use of the RoboFlag simulated environment as a means for profiling multiple dimensions of stress and workload response to a task requiring control of multiple vehicles (robots). It tested the effects of two workload manipulations, environmental uncertainty (i.e., UAV’s visual view area) and maneuverability, in 64 participants. The findings confirmed that the task produced substantial workload and elevated distress. Dissociations between the stress and performance effects of the manipulations confirmed the utility of a multivariate approach to assessment. Contrary to expectations, distress and some aspects of workload were highest in the low-uncertainty condition, suggesting that overload of information may be an issue for UAV interface designers. The strengths and limitations of RoboFlag as a methodology for investigating stress and workload responses are discussed.  相似文献   
135.
Little is known about factors determining which families utilize genetic counseling services. We conducted semistructured interviews with parents of four children born with cystic fibrosis (CF) and ten with Down's syndrome (DS) to ascertain reasons for using, or not using, genetic counseling services in the state of Victoria, Australia. We also explored the usefulness of genetic counseling for the families who had experienced it, and the perceived role of genetic counseling. All mothers of children with CF see a genetic counselor as part of a structured education program following diagnosis through newborn screening. Information overload was identified by them as an important problem. There is no specific program for families of children with DS. Six of them had received genetic counseling and four had not, either because it was not specifically offered to them or because they did not pursue it in the context of misconceptions about its purpose. The timing of the offer of genetic counseling is important and needs to take into account parents' coping strategies after diagnosis. Several parents commented on the favorable aspects of counseling, including getting information they needed to deal with the diagnosis and relief of guilt. Better awareness of genetic counseling by referring physicians, and providing counseling at more than one visit, may contribute to a more effective service.  相似文献   
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137.
Use of the Cognitive Failures Questionnaire (CFQ) in clinical research assumes that the questionnaire measures a single factor. A factor analysis of the CFQ was performed, on a sample of 475 students, using accurate procedures for determining the number of factors. These procedures gave mutually inconsistent results: at least two alternative factor structures can be extracted from the CFQ. An interpretable seven factor solution was found, but the CFQ probably has insufficient items to measure more than two strongly defined factors. The capacity of CFQ multiple factors to predict measures related to stress vulnerability was tested in a further study (N=57). Correlations between CFQ total score and neuroticism and use of coping strategies appeared to depend mainly on a single CFQ multiple factor, related to failures of concentration. Some of the other CFQ factors predicted other criteria. Further research on multiple factors of cognitive failure might improve the validity of the CFQ as a predictor of stress vulnerability and of cognitive performance.  相似文献   
138.
In a free recall task, homogeneity of semantic reference and strong associative connections facilitated the recall after a twenty second filled interval of lists of 18 words. Facilitation in the recall of lists consisting of three sets of six related words when compared with six sets of three related words was also obtained. The organisation present in the recalled sequences is reported using various clustering measures and differences between the measures are indicated and discussed. Difficulties in the use of such measures in evaluating an hypothesis about the relationship between recall and organisation are illustrated and the general theoretical issue of selecting between alternative measures of organisation is considered.  相似文献   
139.
ObjectivesThe objective of this study is to report on the development of an instrument to assess non-physical aspects of physical activity (PA)-related self-worth (SW).MethodsThree hundred thirty five women (mean age = 36.69 ± 15.94 yrs, BMI = 24.87 ± 4.56) completed the Women's Physical Activity Self-Worth Inventory (WPASWI), General SW Scale, and a PA Questionnaire. Rasch analysis was used to evaluate the WPASWI.ResultsThree PA-related SW subscales were identified: PA Knowledge (16 items), PA Emotional (13 items), and PA Social (8 items). Rasch analysis supported construct validity, and items demonstrated acceptable internal consistency (Cronbach's alpha = 0.90, 0.87 and 0.72) and test-re-test reliability (r = 0.79, 0.70, 0.81). Women who reported regular PA participation had higher PA Knowledge, PA Emotional, PA Social, and General SW than those who reported some or no PA (p < 0.01) and correlations between Knowledge, Emotional, and Social SW subscales and General SW were 0.207, 0.130, and 0.220, respectively. PA Knowledge and PA Emotional SW had stronger correlations with PA (r = 0.344, 0.273, respectively) than did General SW (r = 0.133).ConclusionsThe WPASWI demonstrated good internal consistency, reliability, construct validity and a stronger relationship with PA than a General SW instrument.  相似文献   
140.
In a recent article, Gross (2004) argues that physicians in decent societies have a civic duty to aid in the torturing of suspected terrorists during emergency conditions. The argument presupposes a communitarian society in which considerations of common good override questions of individual rights, but it is also utilitarian. In the event that there is a ticking bomb and no other alternative available for defusing it, torture must be used, and physicians must play their part. In an earlier article, Jones (1980) also argues in favour of physician participation in torture, going so far as to enthusiastically endorse the allocation of research resources as well to ensure that the ability to meet emergency situations is as efficient as scientifically possible. I argue against both these views and defend the absolute prohibition against torture generally, and against any participation by physicians in particular. I show that these arguments are incompatible with liberal or decent societies, and that the institutional requirements for making torture effective would constitute an unacceptable degradation both of medical ethics and practice, as well as of political institutions in general.  相似文献   
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