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901.
The afro-saxons     
Ali A. Mazrui 《Society》1975,12(2):15-21
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The first aim of this study was to examine the structure of externalizing and internalizing problem behavior during early adolescence. Our second aim was to determine the stability of these problems for boys and for girls over time. A total of 650, 13–14-year-olds filled out (an expanded version of) the Youth Self-Report [YSR; Manual for the Youth Self-Report and 1991 Profile. Department of Psychiatry, University of Vermont, Burlington] 2 times with a 1-year interval. By using confirmatory factor analyses (CFA) to test a series of competing models, a hierarchical model provided the best representation of the structure of problem behavior at both Time 1 and Time 2: externalizing and internalizing problem behavior represent distinct aspects but the model also demonstrates the existence of comorbidity at a higher level. This model appeared to be stable over time for both boys and girls. The relative stability of problem behavior was found to be high for boys and girls. Absolute stability for both externalizing and internalizing problems appeared to be higher for boys scoring in the lower range of problem behavior. Senior Researcher, Utrecht University, The Netherlands. Received PhD in social sciences, University of Amsterdam. Major research interests include problem behavior, family relations, and peer relations during adolescence. Full Professor, Utrecht University, The Netherlands. Received PhD in social sciences: child and family studies, from University of Nijmegen. Major research interests include adolescent social development, problem behavior, and family relations during adolescence. Assistant Professor, University of Amsterdam, The Netherlands. Received PhD in psychology, University of Amsterdam. Major research interests include family influence on childhood illness and problem behavior.  相似文献   
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The human teeth are a valuable source of information concerning identification and age calculation in forensic sciences. Dental treatment often causes permanent alteration of the teeth, which is visible on radiographs. The correlation of prosthetic restorations, root canal fillings and periodontal bone loss with chronological age has not yet been used for determining the completed 18th year of life in teenagers and young adults, e. g. for legal and anthropological purposes. The aim of this study was to determine whether the evaluation of such findings on radiographs correlates with the chronological age in teenagers and young adults. MATERIAL AND METHODS: The dental X-rays (orthopantomogram, OPG) of 1053 outpatients (age: 14 to 24 years) were avaluated. The values "prosthetically restored", "filled dental root", or "periodontal bone loss" were recorded for each tooth present. The data were then evaluated using statistical tools. RESULTS: The correlation between the number of prosthetically restored teeth and the chronological age is high. The positive predictive value of determining an age of at least 18 years proved to be very high. However, these findings are rarely present in this age group. The number of endodontically treated teeth correlated less exactly with age. On the other hand, the determination of periodontal bone loss gave reasonable positive predictive values for the threshold value "chronological age of 18 years or more". DISCUSSION: This study provides for the first time predictive values for the estimation whether a person is 18 years of age, based on the evaluation of teeth with prosthetic restorations, root canal fillings or periodontal bone loss on OPGs only. Whereas the number of patients with such findings is generally low in this age group, some of the positive findings can be used for age estimation as an adjunct to other sources of age calculation. The sole application of these criteria is not recommended, as sanitary conditions of the teeth depend on both social and individual circumstances. Therefore, the calculated values also reflect the culture of the sample studied. Finally, they are time-dependent and have to be compared to data from other populations. These results have some bearing on the field of forensic odontology.  相似文献   
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