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111.
Two previous studies found that life stress and parental alcoholism were not as highly related to distress for Hispanic adolescents as they were for European American adolescents (M. Barrera Jr., S. A. Li, and L. Chassin, 1993, 1995). Those findings could be interpreted as evidence of Hispanic youths' resilience, but limitations of the stress measure and the homogeneity of the Hispanic sample threatened this interpretation. The present study improved on those previous studies by using a new measure of uncontrollable stressors and a more heterogeneous Mexican American sample. Participants in this study were 175 Mexican American and 59 European American adolescents and their parents. Unlike the previous studies, results did not show that Mexican American adolescents were more resilient to parental problem drinking or life stress than were European American adolescents. Overall, life stress was related to adolescents', mothers', and fathers' reports of adolescents' psychological distress above and beyond the effects of ethnicity and socioeconomic factors.  相似文献   
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Change in cognitive abilities was assessed over a 6-year period in a sample of monozygotic and same-sex dizygotic twin pairs (N = 507 individuals), aged 80 and older (mean age = 83.3 years: SD = 3.1). who remained nondemented over the course of the study. Latent growth models (LGMs) show that chronological age and time to death are consistent predictors of decline in measures of memory, reasoning, speed, and verbal abilities. Multivariate LGM analysis resulted in weak and often negative correlations among rates of change between individuals within twin pairs, indicating greater differential change within twin pairs than occurs on average across twin pairs. These findings highlight several challenges for estimating genetic sources of variance in the context of compromised health and mortality-related change.  相似文献   
114.
Data regarding individual differences in children's regulation, emotionality, quality of socioemotional functioning, and shyness were obtained from teachers and peers for 112 Indonesian 6th graders. Similar data (plus parents' reports) also were collected when these children were in 3rd grade. For boys, regulation and low negative emotionality generally predicted positive socioemotional functioning (e.g., social skills, adjustment, prosocial tendencies and peer liking, sympathy) within and across time and across reporters, even at the follow-up when initial levels of regulation or negative emotionality were controlled. For girls, relations were obtained primarily for concurrent teacher reports, probably because girls tended to be fairly well regulated and socially competent and variability in their scores was relatively low. Shyness for both sexes tended to be associated with concurrent measures of low regulation, high negative emotionality, and low quality of social competence.  相似文献   
115.
In previous studies of attentional focus effects, investigators have measured performance outcome. Here, however, the authors used electromyography (EMG) to determine whether difference between external and internal foci would also be manifested at the neuromuscular level. In 2 experiments, participants (N=11, Experiment 1; N=12, Experiment 2) performed biceps curls while focusing on the movements of the curl bar (external focus) or on their arms (internal focus). In Experiment 1, movements were performed faster under external than under internal focus conditions. Also, integrated EMG (iEMG) activity was reduced when performers adopted an external focus. In Experiment 2, movement time was controlled through the use of a metronome, and iEMG activity was again reduced under external focus conditions. Those findings are in line with the constrained action hypothesis (G. Wulf, N. McNevin, & C. H. Shea, 2001), according to which an external focus promotes the use of more automatic control processes.  相似文献   
116.
The authors examined the influence that attentional focus on either a postural or a suprapostural task had on the performance of each task. Participants (N = 32) stood on an inflated rubber disk and held a pole horizontally. All participants performed under 4 attentional focus conditions: external (disk) or internal (feet) focus on the postural task, and external (pole) or internal (hands) focus on the suprapostural task. Compared with internal focuses, external focuses on either task resulted in similar and reduced postural sway. Response frequency on each task increased when participants focused on the respective task. Finally, an external focus on either task produced higher frequencies of responding on the suprapostural task. The authors conclude that suprapostural task goals have a stronger influence on postural control than vice versa, reflecting the propensity of the motor system to optimize control processes on the basis of the desired movement effect.  相似文献   
117.
Asymmetrical gait patterns such as the gallop provide insight into the complexity of human locomotion. The nature of spontaneous (e.g., walk-run), quasi-spontaneous (e.g., gallop-walk), and intentional (e.g., walk-gallop) transitions was analyzed in 2 ways in the present study. In Analysis 1, the authors used step-wise regression to associate 10 physical characteristics with gait transitions. Transition predictability was moderate; thigh length best predicted 3 of 6 transitions. In Analysis 2, the dynamic characteristics of transitions (order parameters, phase shifts, multistability, and critical fluctuations) were described; those characteristics existed for all transition types. The results of the analyses suggest that intentional transitions are less biomechanically predictable than are spontaneous transitions and that transitions between gait pairs (e.g., walk-gallop and gallop-walk), regardless of velocity direction, have more in common than do transitions requiring specific intention.  相似文献   
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119.
This study describes the effects of different weekly work intensity levels on adolescent functioning in a sample of 3,083 high school students in rural South Texas, where economically disadvantaged and Hispanic youth are heavily represented. Anonymous surveys were conducted in 10th- and 12th-grade students' classrooms in 1995. The following effects were associated with long hours of weekly employment during the school year: (1) decreased performance/engagement in school and satisfaction with amount of leisure time, and (2) increased health risk behaviors and psychological stress. The effects of school-year work on academic factors and health behaviors differed by grade, but not by race/ethnicity, parent education, or race/ethnicity and parent education considered together. It was concluded that parents and professionals should continue to monitor the number of weekly hours that students work during the school year.  相似文献   
120.
This paper explores a particular constellation of fantasies and defenses that in some women leads to the delay of childbearing. Destructive wishes towards the woman's own womb and her mother's lead to behaviors that sabotage fertility and pregnancy. These wishes and behaviors meet up with an unconscious belief in and commitment to time standing still, and with cultural tropes and trends that obscure intrapsychic conflicts and denials about motherhood, aging, and time. Analysis, like childbearing, is constrained by the reality of time, and the complex untangling and connecting of these three not obviously related threads may not occur until it is, for the woman who wants a child, too late.  相似文献   
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