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91.
Of 778 gay and bisexual men (none with acquired immunodeficiency syndrome [AIDS]), 27% (n = 212) reported suicidal ideation over the previous 6 months. Covariance structure models were used to explore predictors of suicide intent among (n = 112) suicide ideators with (n = 100) and without (n = 112) human immunodeficiency virus (HIV). Current AIDS-related stressors (deaths and illnesses and perceived AIDS risk) and past levels of adaptive functioning (social isolation and depression) were significantly more powerful predictors of suicide intent among HIV-positive than among HIV-negative ideators. Biological AIDS risk predicted neither suicide intent, current distress, nor perceived AIDS risk. Pathways to suicide intent appear to be psychologically, rather than biologically, mediated. Among HIV-positive ideators, AIDS-related death and illness events predicted suicide intent but not current distress symptoms. Some suicidal ideation in response to AIDS-related events may be an effort to cope rather than a manifestation of psychological distress.  相似文献   
92.
How a chronic environmental stressor can interfere with the buffering effects of social support by eroding social support was analyzed in this prospective, longitudinal study. A classic buffering effect of support was found after 2 months of exposure to the stressor, household crowding. Crowded residents with low perceived support had greater increases in psychological distress than did crowded residents with high perceived support. However, after 8 months exposure the buffering effect disappeared. Moreover, greater crowding had become directly associated with lower support, which in turn was associated with greater increases in psychological distress. All analyses controlled for prior distress. Under some types of chronic stress, the buffering effects of social support may be short-lived because the stressor eventually erodes social support.  相似文献   
93.
Responsiveness of 1-, 3-, and 5-year-old children and adults to octave-band noises at .4 and 10 kHz was assessed with a go/no-go version of visual reinforcement audiometry (VRA) (Moore, Thompson, & Thompson, 1975) and a two-alternative, forced-choice version (Suzuki & Ogiba, 1961; Trehub, Schneider, & Endman, 1980). Infants performed better on the two-alternative, forced-choice version in quiet and in noisy backgrounds, and adults performed better on the two-alternative, forced-choice version in quiet but not in noisy backgrounds. Performance on the two tasks was essentially equivalent for 3- and 5-year-old children. Superior performance on two-alternative VRA over go/no-go may be due to lesser cognitive demands in the case of infants and to the engagement of superior decision strategies in the case of adults.  相似文献   
94.
In pairwise multidimensional scaling, a spatial representation for a set of objects is determined from comparisons of the dissimilarity of any two objects drawn from the set to the dissimilarity of other pairs of objects drawn from that set. In pairwise conjoint scaling, comparisons among the joint effects produced by pairs of objects, where the objects in a pair are drawn from separate sets, are used to determine numerical representations for the objects in each set. Monte Carlo simulations of both pairwise dissimilarities and pairwise conjoint effects show that Johnson's algorithm can provide good metric recovery in the presence of high levels of error even when only a small percentage of the complete set of pairwise comparisons are tested.  相似文献   
95.
Trajectory and kinematics of drawing movements are mutually constrained by functional relationships that reduce the degrees of freedom of the hand-arm system. Previous investigations of these relationships are extended here by considering their development in children between 5 and 12 years of age. Performances in a simple motor task--the continuous tracing of elliptic trajectories--demonstrate that both the phenomenon of isochrony (increase of the average movement velocity with the linear extent of the trajectory) and the so-called two-thirds power law (relation between tangential velocity and curvature) are qualitatively present already at the age of 5. The quantitative aspects of these regularities evolve with age, however, and steady-state adult performance is not attained even by the oldest children. The power-law formalism developed in previous reports is generalized to encompass these developmental aspects of the control of movement.  相似文献   
96.
Fluid noncompliance in patients with end-stage renal disease (ESRD) is a widespread problem with severe consequences for health. In addition, ESRD patients report considerable stress in relation to their illness and dialysis treatment. The present study examined the role of cognitive and emotional variables in fluid noncompliance, symptomatology, and stress. Fifty hemodialysis patients were assessed (a) on the cognitive variables of locus of control, self-evaluations of their past compliance, and self-efficacy to resist fluid intake and (b) on the emotional variables of depression, anger, and anxiety. Results showed that cognitive variables accounted for fluid noncompliance and predicted future adherence. Patients high in negative emotions complied equally as well as patients low in negative emotions but were found to report substantially more symptomatology and distress associated with their treatment. The implications of these findings for treatment of ESRD patients and future research are discussed.  相似文献   
97.
AIDS-related stressors were studied in relationship to suicidal ideation and suicide intent among 778 gay and bisexual men (none with AIDS). Over the previous six months, 27% (n = 212) reported suicidal ideation. Subjects who reported suicidal ideation (compared to those who did not) were more likely to report recent (last 6 months) bereavement of partner, recent ARC diagnosis, and multiple close friends with ARC. Suicide ideators were divided by a median split on a self-report scale of suicide intent into low (n = 105) and high (n = 107) intent suicide ideators. News of HIV seropositivity was specifically related to low intent suicidal ideation. High intent suicidal ideation was associated with having a partner with AIDS or ARC, or multiple close friends with AIDS, or having ARC. Generally speaking, while temporally discrete AIDS-related events were associated the report of suicidal ideation, ongoing stressors which may more greatly challenge adaptational capacities were more associated with high intent suicidal ideation.  相似文献   
98.
Reliable monitoring of the movement of small aquatic animals presents some unique problems. In the case of the larval salamander, the animal may be less than an inch long and move in sporadic short bursts. A device is described that utilizes infrared emitters and wide-band sensors inter-faced to a computer for monitoring location and movement of animals between light and dark environments over extended periods of time. The system employs a multiplexed digital input, is inexpensive, and can be easily expanded to deal with a range of monitoring problems that may occur with a wide range of both aquatic and terrestrial species.  相似文献   
99.
Traditional assumptions that sex-role conformity is positively related to psychological adjustment in young children have not, to date, been examined empirically. Seventy-four preschool children, 37 boys and 37 girls aged 3 to 5, were observed over a 3-month period to determine their frequency of play in male and female sex-typed activities during the free-play period in their classrooms. Teacher ratings on the Kohn and Rosman Symptom Checklist and Social Competence Scale were correlated with individuals' rates of play in male and female preferred activities (M and F scales, respectively). Results indicated that boys' play with male-preferred toys was related to high scores on the aggression/defiance dimension of the Symptom Checklist, while boys who scored highly on play in female-preferred activities received high scores on the Social Competence dimension labeled conforming to classroom rules. For girls, play with malepreferred toys was negatively related to the apathy/withdrawal dimension of the Symptom Checklist. These results do not confirm the hypothesis that sex-typed behavior is positively related to adjustment, and they suggest that for both sexes, play in opposite sex-typed activities may contribute positively to children's social and academic functioning in the classroom.This research was supported in part by Grant No. MH25751-06 from the National Institute of Mental Health, and by a grant from the Programme de Formation de Chercheurs et d'Action Concertée, Ministére de l'Education, Gouvernement du Québec. Portions of this paper were presented at the biennial meeting of the Society for Research in Child Development, Boston, April 1981.  相似文献   
100.
Several studies of choice behavior (risk taking) in achievement-oriented situations are reanalyzed. The usual ways of pooling all choices over trials and subjects conceal the series of subjects' decisions and the dynamics inherent in these decisions. A basic strategy of subjects in an achievement-oriented choice situation seems to be to start with an easy task, choose a more difficult one whenever you succeed, and stay mostly at the same difficulty level whenever you fail. A computer model, in which such simple assumptions are made, generates preference functions over the order of difficulty levels that are indistinguishable from those found in empirical studies. It is concluded that the study of choice behavior in achievement-oriented situations should be based on the analysis of the series of single decisions by one subject. For this we need models that allow the predictions of such decisions and the prediction of action-controlling cognitions and emotions.  相似文献   
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