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Michael A. Hoffman Rachel Levy-Shiff Varda Ushpiz 《Journal of youth and adolescence》1993,22(1):23-31
The study assessed whether the impact of social support on self-esteem is moderated by the adolescent's orientation toward the source of aid. Questionnaires were administered to 84 Israeli adolescents regarding self-esteem, perceived level of support from parents and peers, and preference, or orientation, for support from these sources. Regression analyses indicated that the positive effect of social figures' support on self-esteem increased as a function of interest in receiving aid from the specific source. Correlational analyses also revealed that heightened orientation toward parents was associated with higher levels of perceived parental support, whereas heightened orientation toward peers was associated with higher levels of peer support and lower levels of parental aid. These findings were consistent with self-evaluation maintenance and social provision theories, which suggest that the individual has an active role in selectively seeking out and filtering external social influences.His doctorate in educational psychology is from UCLA. Current research interests include stress and coping across the life span, social sources of adolescent self-esteem, and intergroup relations in the junior high school.Her doctorate in clinical psychology is from the Hebrew University in Jerusalem. Her research interests include family relations, social and emotional development in children and adolescents, and developmental psychopathology.Her research interests focus on social support in the family. 相似文献
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Does sexual dimorphism in facial soft tissue depths justify sex distinction in craniofacial identification? 总被引:1,自引:0,他引:1
Separation of male and female soft tissue depths into discrete groups for craniofacial identification implies that males and females differ enough from each other, with respect to this application, for this distinction to be useful. In this study, previously published soft tissue depth data were analyzed for sex separation. It was found that the variation within each sex was large while the variation between the sexes was small. Often the value of two standard deviations of the measurement for either sex was larger than the difference displayed between the means of each sex. Furthermore, opposite sex overlap in regions defined to be close to the male or female mean were found to be large and the amount of variance explained by sex was small (less than 6% on average). These results indicate that while male and female means at single craniofacial landmarks may differ slightly, and even at statistically significant levels, individual male and female soft tissue depths are often the same or very similar. On average, soft tissue depths of the face do display some sexual dimorphism but it is not marked and of little practical meaning for craniofacial identification where a single individual must be independently considered. Thus, there is little use in separate reporting of data for males and females and data should be combined to increase sample sizes. 相似文献
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The fingernails of Mary Sullivan, the last victim of the Boston Strangler, were examined to determine if any genetic information about the murderer could be obtained. The nails were extremely friable necessitating the development of new techniques for isolating and purifying DNA. DNA yields from nails were optimized by using a NaOH-based preparation technique, which was simple, efficient, and minimized handling. Methods for selectively and thoroughly removing exogenous material on nails were also developed through use of a species-specific PCR assay, wherein mitochondrial DNA from the nail could easily be differentiated from DNA of contaminating cells. 相似文献