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Each partition of a population defines a homomorphic mapping of sociometric graphs onto a corresponding set of image graphs. For sets of images selected by substantive importance, the expected number of mappings is calculated when the array of sociometric graphs is drawn at random with equal probabilities. Upper and lower bounds are computed for the probability of finding at least one mapping from an array to the given images, and for the expected number of mappings given that there is at least one. Results of small Monte Carlo trials are reported.  相似文献   
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Four rhesus monkeys were trained to respond on one key when a one-second noise burst was presented through one speaker and to respond on a second key when the noise burst was presented through a second speaker. The acquisition of stimulus control was studied under three conditions, in each of which the relationship between the sound source and the response-key positions varied: an adjacent condition in which the noise burst was presented through the key and a response on this key was reinforced; a reversed-adjacent condition in which the noise burst was presented through one key and responding on the other key was reinforced: and a nonadiacent condition in which responding on the key nearer the sound was reinforced. Under adjacent conditions, stimulus control developed within one or two sessions. Under reversed and nonadjacent conditions, 10 sessions were required for the development of control. The asymptote of correct responding was the same under each condition in all animals.  相似文献   
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Sixteen observers palpated silicone models of human breasts containing lumps 1.6-12.1 mm in diameter. Detectability depended on the size of the lump, producing a systematic psychometric function. In eight observers who participated in three or more sessions, performance improved with practice, with most improvement occurring within one or two 26-trial sessions. Three-week retention measures disclosed no appreciable decrease in performance, but a significant correlation was found between the number of lumps detected and duration of trial (p < .01). There was no difference in performance between four observers who used their preferred hands and four observers who used their nonpreferred hands. These data establish that examination of breast models for the detection of lumps simulating cancer is a task amenable to experimental analysis.  相似文献   
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Journal of Religion and Health - Identifying reforms that minimize US healthcare costs is imperative. This commentary explores one intervention with potential cost-saving implications that has...  相似文献   
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Transitioning from an acute psychiatric care setting to a less restrictive environment after a suicidal event is arguably the most critical period of suicide risk for adolescents, making comprehensive safety and coping plans for this population ever more critical. In this paper we provide theoretical and empirical rationale for the need for developmental adaptations to current safety planning procedures for suicidal adolescents, as well as the standardization of pediatric safety plans for broader use across settings that provide acute psychiatric care to adolescents. We describe how we developed the Adolescent Safety and Coping Plan (ASCP) using qualitative in-depth interviews with 20 adolescents and their parents, explain the specific components of the ASCP, and give a case example of the ASCP being used with a young adolescent and her parents. Finally, we conclude with a discussion of the barriers and facilitators of the use of the ASCP in settings that provide acute psychiatric care, as well as the need for future research to test the ASCP with diverse adolescent and family populations and settings.  相似文献   
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