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The purpose of this study was to increase the knowledge base of adolescent substance use by examining the influences of risk and protective factors for specific substance use, namely alcohol, cigarettes, and marijuana. Participants included 271 adolescents and their primary caregivers referred for mental health services across North Carolina. A series of hierarchical multiple regressions showed that the relative influences of risk and protective factors differed depending on the target substance in some cases. History of parental felony predicted use of all 3 substances, although the direction of association was substance specific. Parental behavioral control (how families express and maintain standards of behavior) was predictive only of cigarette and marijuana use, not alcohol use. The different links among risk factors, protective factors, and specific substance use are discussed, and recommendations for both mental health and substance use professionals are offered.She received her M.A. in Psychology from Wake Forest University and is currently a doctoral student in Clinical Psychology at the University of North Carolina at Greensboro. Her major research interests include developmental pathways to aggressive behavior among females.An evaluator for the North Carolina Department of Health and Human Services, her major research interests include system of care intervention programming.She received her PhD in Clinical Psychology from Purdue University. Her major research interests include developmental psychopathology and early intervention.His research interests focus on youth violence and youth involved with the juvenile justice system.She received her PhD in Clinical Psychology from the University of North Carolina at Greensboro. Her research interests focus on early intervention with young children.  相似文献   
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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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A clear positive case for anabolic steroids doping was confounded by alleged urine tampering during doping control procedures. Review of the chain of custody showed no flaws, but nevertheless the athlete was adamant that the urine sample should be analyzed for DNA in order to support her contention that she was not the donor of the sample. The results obtained showed that the urine sample that scored positive for steroids contained nuclear DNA that could not be matched to the DNA obtained from the athlete's blood. On the other hand, the same urine sample contained mitochondrial DNA whose nucleotide sequences spanning the hyper variable regions HV1 and HV2 proved to be identical to those determined in mitochondrial DNA amplified from the athlete's blood. The occurrence of an extraneous genotype is compatible with exogenous nuclear DNA admixture to the athlete's urine. Alternatively, taking in consideration the mitochondrial DNA, we could not exclude that a sibling or a maternal relative of the athlete could have acted as a donor of the urine utilized for doping control and DNA analysis. Both situations point to possible tampering of the urine by the athlete. Adjudication at CAS maintained previous national and international federation decision that there was no proof of a chain of custody flaw to justify the athlete's allegation of urine substitution after collection.  相似文献   
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