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511.
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The purpose of this study was to examine the associations between using unhealthy substances and the digit ratio (2nd to 4th digit length ratio, 2D:4D) which is supposed to indicate the prenatal testosterone level. The subjects were 455 students, 225 women and 230 men. Participants declared their frequency of smoking and alcohol drinking. There was no significant difference in digit ratios between subjects regularly using both nicotine and alcohol and those who took none of them. When analyzing the two substances separately, there was no relationship between 2D:4D and alcohol drinking, whereas left hand 2D:4D was positively related to smoking only for women (nonsignificant trend was observed for right hand). Contrary to the previous study, our results indicate that there is no relationship between 2D:4D and alcohol drinking. There is, however, a subtle influence of prenatal testosterone levels for cigarette smoking habits in the case of women.  相似文献   
513.
A very simple derivation is given for the dependence of localisation length on boundary velocity and various model parameters, in the continuum theory of 2D foam shear localisation. It is pointed out that the existence of distinct yield and limit stresses can complicate this theory for low boundary velocities, by introducing another mechanism for localisation, which does not depend on wall drag.  相似文献   
514.

Much attention has been given to determining whether an adolescent patient has the capacity to consent to research. This study explores the factors that influence adolescents' decisions to participate in a research study about youth violence and to determine positive or negative feelings elicited by being a research subject. The majority of subjects perceived their decision to participate to be free of coercion, and few felt badly about having participated. However, adolescents who were alone in the room during the assent process were more likely to report that they chose freely to be a research subject. This study may influence the ways physicians communicate with adolescent patients around research assent within a clinical care environment.  相似文献   
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Standard discussions of prudence treat it as requiring time-slice management. That this is the standard view of prudence can be seen by its presence in two seemingly opposed positions on prudence, those of Thomas Nagel and Derek Parfit. I argue that this kind of view fails to properly appreciate the difficulty with being prudent, treating imprudence as a kind of theoretical mistake. I then offer a characterization of prudence as integrity, the holding together of disparate but temporally extended parts of the self in a manner that makes the act of reasoning possible.  相似文献   
517.
Olson (1997a) tries to refute the Psychological Approach to personal identity with his Fetus Argument, and Mackie (1999) aims to do the same with the Death Argument. With the help of a suggestion made by Baker (1999), the following discussion shows that these arguments fail. In the process of defending the Psychological Approach, it is made clear exactly what one is and is not committed to as a proponent of the theory.  相似文献   
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In this paper, we assessed the efficacy of different types of visual information for improving the execution of the roundoff movement in gymnastics. Specifically, two types of 3D feedback were compared to a 3D visualization only displaying the movement of the expert (observation) as well as to a more ‘traditional’ video observation. The improvement in movement execution was measured using different methods, namely subjective evaluations performed by official judges, and more ’quantitative appraisals based on time series analyses. Video demonstration providing information about the expert and 3D feedback (i.e., using 3D representation of the movement in monoscopic vision) combining information about the movement of the expert and the movement of the learner were the two types of feedback giving rise to the best improvement of movement execution, as subjectively evaluated by judges. Much less conclusive results were obtained when assessing movement execution using quantification methods based on time series analysis. Correlation analyses showed that the subjective evaluation performed by the judges can hardly be predicted/ explained by the ‘more objective’ results of time series analyses.  相似文献   
520.
近年来随着研究的深入,发现维生素D除了调节钙磷代谢外,对先天性免疫、适应性免疫亦具有调节作用,其不仅能降低重症加强治疗病房(ICU)内多器官衰竭的病死率,还能预测疾病的严重程度及预后,在危重患者中具有广阔的应用前景,可作为ICU的一种辅助治疗手段。  相似文献   
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