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Recent clusters of teenage suicides in Texas suburban communities have focused national attention on the rise in teenage suicidal behavior. This study sought to clarify the teenage suicide phenomenon by using a cohort method of data analysis. Beginning with suicide rates for white males aged 15-19 in 1945, suicide rates were calculated and plotted for each 5-year age cohort entering the late teenage years, when suicide risk factors dramatically increase. Our analysis of these cohort patterns confirmed the ever-rising risk factor associated with the ages of 15-19. This trend is consistent with many studies suggesting that teenage suicide is a function of socioeconomic and psychological factors operating across community and national boundaries. In addition, our study revealed that as white males 15-19 years of age in 1945 aged, their suicide rates also increased, confirming earlier findings that the suicide risk factor increases with age. In fact, Texas data for 1980 revealed that older persons, not teenagers, had the highest suicide rates-a finding that confirms other studies' results. Finally, Texas cohort patterns for suicide revealed the recent curvilinearity tendencies of older adult male suicide rates. By 1980 Texas data revealed a bimodal distribution of high suicide risk, with white males in their late 20s and ages 55 and over having the highest rates.  相似文献   
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Evidence from a number of sources now suggests that the visuo-spatial sketchpad (VSSP) of working memory may be composed of two subsystems: one for maintaining visual information and the other for spatial information. In this paper we present three experiments that examine this fractionation using a developmental approach. In Experiment 1, 5-, 8-, and 10-year old children were presented with a visuo-spatial working memory task (the matrices task) with two presentation formats (static and dynamic). A developmental dissociation in performance was found for the static and dynamic conditions of both tasks, suggesting that the activation of separable subsystems of the VSSP is dependent upon a static/dynamic distinction in information content rather than a visual/spatial one. A highly similar pattern of performance was found for a mazes task with static and dynamic formats. However, one strategic activity, the use of simple verbal recoding, may also have been responsible for the observed pattern of performance in the matrices task. In Experiments 2 and 3 this was investigated using concurrent articulatory suppression. No evidence to support this notion was found, and it is therefore proposed that static and dynamic visuo-spatial information is maintained in working memory by separable subcomponents of the VSSP.  相似文献   
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T his study examined factors associated with the medical severity of suicide attempts focusing on demographic characteristics, mental health characteristics, and the circumstances of the suicide attempt. Analyses were based on 153 nearly lethal suicide attempters and 47 less lethal suicide attempters aged 13–34 years who presented to emergency departments in Houston, Texas. The results show that young age was significantly associated with a nearly lethal suicide attempt. Prior suicide attempts, hopelessness, depression, and help‐seeking (ever) were significantly and negatively associated with a nearly lethal suicide attempt. None of the suicide attempt factors occurring prior to the attempt were associated with a nearly lethal suicide attempt.  相似文献   
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