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Suicides among older adults in the United States and Canada in the last decade have accounted for an increasing share of all suicides. In both countries the use of firearms among older adults has steadily increased. Despite these trends, little is known about the extent to which crisis centers are prepared to prevent elder suicide. A survey of AAS-listed crisis prevention centers examined the training, knowledge, and current practices relevant to elder suicide among personnel in 321 crisis prevention centers in both countries. Results revealed insufficient training, a lack of familiarity with recent suicide trends, and limited outreach to older adults.  相似文献   
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How do speakers design what they say in order to communicate effectively with groups of addressees who vary in their background knowledge of the topic at hand? Prior findings indicate that when a speaker addresses a pair of listeners with discrepant knowledge, that speakers Aim Low, designing their utterances for the least knowledgeable of the two addressees. Here, we test the hypothesis that speakers will depart from an Aim Low approach in order to efficiently communicate with larger groups of interacting partners. Further, we ask whether the cognitive demands of tracking multiple conversational partners' perspectives places limitations on successful audience design. We find that speakers can successfully track information about what up to four of their partners do and do not know in conversation. When addressing groups of 3–4 addressees at once, speakers design language based on the combined knowledge of the group. These findings point to an audience design process that simultaneously represents the perspectives of multiple other individuals and combines these representations in order to design utterances that strike a balance between the different needs of the individuals within the group.  相似文献   
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Cancellation tests are commonly used in the clinical assessment of visuospatial function, but there has been little study of task characteristics influencing performance. This study was designed to assess factors which affect cancellation performance. Sixteen healthy subjects sequentially performed four random-array letter cancellation tasks. The forms contained 50 and 100 stimuli and target:distractor (T/D) ratios of 1:4 and 1:9 with target letter “A” and randomly selected letter distractors. The primary performance measure was calculated as the number of correctly cancelled targets divided by the time to complete the task, corrected for accuracy. This measure revealed a strong effect of T/D ratio (p< .0001), with performance adversely affected by higher proportion of distractors. There was no effect of stimulus number. This suggests that T/D ratio should be considered in cancellation test design and interpretation.  相似文献   
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