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111.
Men have previously been reported to exhibit seasonal fluctuations on specific types of cognitive performance. It has been speculated that this performance variability is a result of changes in cerebral asymmetry due to lowered testosterone concentrations in the spring relative to the fall. In the present study, functional cerebral lateralization was measured in a group of men and women in the spring and fall. Free testosterone concentrations were assessed for participants to determine what associations might exist between seasonal variability in lateralization and seasonal fluctuations in testosterone exposure. Men and women tested in the spring exhibited exaggerated patterns of asymmetry compared to participants tested in the fall. Lower testosterone concentrations were observed in the spring compared to the fall in women, but not men. No direct associations between testosterone and lateralization were detected for either sex at either season. These results illustrate that seasonal fluctuations in testosterone exposure do not directly influence seasonal changes in functional lateralization patterns.  相似文献   
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The purpose of this study was to identify factors associated with early onset of sexual intercourse. Within an ecological system's conceptual framework, familial factors associated with early onset of sexual activity were identified in a sample of 425 adolescents from San Juan metro area schools. Measures included questions about sexual activity, sexual permissiveness, and such familial variables as: discipline, parental supervision, and parental support. Significant relationships were observed between early onset of sexual intercourse and parental supervision, discipline, parental support, and parents' marital status. Results suggest the key role of parents and family in prevention of HIV-risk behaviors among adolescents in terms of delaying sexual onset. Overall, the study described youths who postponed sexual activity as having greater support, supervision, and parental involvement.  相似文献   
116.
The purpose of this study was to examine the Body Mass Index of 180 female Spanish Olympic athletes (M age = 27.1 yr., SD = 5.9 yr.) who participate in presentation sports and nonpresentation sports, in comparison with 114 female nonathletes (M age = 20.7, SD = 1.5 yr.). Presentation sports athletes have a profile similar to that of a university student but by age with a lower Body Mass Index. In particular, rhythmic gymnasts have a lower weight and Body Mass Index than other athletes and nonathletes.  相似文献   
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On March 11, 2004, Al-Qaeda set off 10 bombs on several train routes in Madrid. 192 people were killed and 2,000 wounded. In this study, 1,179 questionnaires were administered Week 2 after the attacks to residents 18 years and over from the affected geographical areas. The questionnaire included items about sociodemographic variables and exposure to the attacks. Psychological effects were assessed as presence of acute stress and depressive symptomatology and functional impairment. 46.7% of the sample presented symptomatology of acute stress and 49.6% depressive symptoms. Among the symptoms of acute stress, the most frequent were re-experiencing (72.5%) and dissociative symptoms (71.8%). The chief predicting variables in symptomatology were being female, over 65 yr. old, and a habitual train user. The large number of affected people was refined with an item analysis and the consideration of severity of interference in psychosocial functioning.  相似文献   
118.
Confirmatory factor analysis examined the factor structure of DSM IV Attention Deficit Hyperactivity Disorder symptoms and analyzed the differences in informants' ratings of ADHD symptoms by children's age and sex. A sample of 1,018 Spanish school children, 574 girls and 444 boys, ages 4 to 12 years, was rated by teachers and parents. Confirmatory factor analysis showed a similar fit for the three-factor model of Inattention, Hyperactivity, and Impulsivity (teachers: CFI = .976, RMR = .041, % of total variance = 83.2; parents: CFI = .969, RMR = .037, % of total variance = 82.7) and for the two-factor model of Inattention and Hyperactivity Impulsivity (teachers: CFI = .958, RMR = .044, % of total variance = 79.3; parents: CFI = .961, RMR = .038, % of total variance, 79.9). The two-factor model was selected as a parsi monious representation of the teachers' and parents' ratings of ADHD symptoms. Analyses of variance indicated significant differences in teachers' and parents' mean ratings across sex and school grades of children.  相似文献   
119.
This study examined the dimensional structure of Tomás-Sábado and Gómez-Benito's Death Anxiety Inventory and Templer, et al.'s Death Depression Scale-Revised. The responses of 244 Spanish nurses to the Spanish forms of both scales were evaluated by means of a principal axis factor analysis with direct Oblimin rotation. Five significant factors were identified: Internally Generated Death Anxiety, Death Depression, Externally Generated Death Anxiety, Death Threat, and Death Sadness, accounting for 51.6% of the variance. The distribution of the factor loadings for the items of both scales on the five factors supported the discriminant validity of the constructs specific to each of the scales and justified their use in evaluating death anxiety and death depression independently.  相似文献   
120.
Sheehan's shortened form of Betts' Questionnaire Upon Mental Imagery is one of the most widely used inventories for measuring imaging. Participants were 562 undergraduate students (414 women and 148 men), with a mean age of 20.2 yr. In a principal components analysis followed by varimax orthogonal rotation for the Spanish version, eight factors were identified, six of which coincide with those of the original English version. Internal consistency was .92 (Cronbach alpha). Scores on the Betts Questionnaire Upon Mental Imagery correlated -.34 with those on the Gordon Test of Visual Imagery Control, .58 with those on the Vividness of Visual Imagery Questionnaire, and .02 with the Verbalizer-Visualizer Questionnaire.  相似文献   
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