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891.
892.
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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The DNA dragnet     
Ripley A 《Time》2005,165(4):39-40
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897.
The increasingly global role of a forensic anthropologist necessitates a proper means for archiving evidence for re-examination. Large quantities of evidence can be stored and be made readily accessible through digital imaging. This study focuses on age assessment from digital photographs for personal identity reconstructions. A comparison of 52 Suchey-Brooks scores assigned to digital images and actual bone revealed that age assessment from digital images can be completed with accuracy. Coefficients of concordance imply that there significant agreement between osteological assessment of aging criteria from digital images and direct observation-greater than random change alone (p < 0.05). However, assessments from images should be approached with caution since there are inherent limitations of the naked eye in identifying morphological changes in certain skeletal features, especially where older adults are concerned. Although there is no replacement for a hands-on physical assessment, a digital archive may facilitate the global needs of the forensic anthropologist.  相似文献   
898.
Samples containing DNA from two or more individuals can be difficult to interpret. Even ascertaining the number of contributors can be challenging and associated uncertainties can have dramatic effects on the interpretation of testing results. Using an FBI genotypes dataset, containing complete genotype information from the 13 Combined DNA Index System (CODIS) loci for 959 individuals, all possible mixtures of three individuals were exhaustively and empirically computed. Allele sharing between pairs of individuals in the original dataset, a randomized dataset and datasets of generated cousins and siblings was evaluated as were the number of loci that were necessary to reliably deduce the number of contributors present in simulated mixtures of four or less contributors. The relatively small number of alleles detectable at most CODIS loci and the fact that some alleles are likely to be shared between individuals within a population can make the maximum number of different alleles observed at any tested loci an unreliable indicator of the maximum number of contributors to a mixed DNA sample. This analysis does not use other data available from the electropherograms (such as peak height or peak area) to estimate the number of contributors to each mixture. As a result, the study represents a worst case analysis of mixture characterization. Within this dataset, approximately 3% of three-person mixtures would be mischaracterized as two-person mixtures and more than 70% of four-person mixtures would be mischaracterized as two- or three-person mixtures using only the maximum number of alleles observed at any tested locus.  相似文献   
899.
Infectious microorganisms are important to multiple communities engaged in biodefense and biosecurity, including the agencies responsible for health, defense, law enforcement, agriculture, and drug and food safety. Many agencies have created lists of high priority infectious microorganisms to prioritize research efforts or to formally control the possession and distribution of specific organisms or toxins. However, the biological classification of infectious microorganisms is often complex and ambiguous, leading to uncertainty and confusion for scientists involved in biosecurity work. To address this problem, we created a database, known as the Microbial Rosetta Stone, which resolves many of these ambiguities and includes links to additional information on the microbes, such as gene sequence data and scientific literature. Here we discuss the efforts to coordinate organism names from pathogen lists from various governmental agencies according to biological relatedness and show the overlap of high-priority organisms from multiple agencies. To our knowledge, this is the first comprehensive coordination of pathogens, synonyms, and correct taxonomic names. The organized tables and visual aids are freely available at http://www.microbialrosettastone.com. This website provides a single location where access to information on a broad range of disease-causing organisms and toxins is available to members of the biosecurity community.  相似文献   
900.
Efficient capillary electrophoretic STR analysis requires rapid, reproducible and robust separation of DNA fragments with reasonable capillary longevity--this is currently accomplished using proprietary commercial polymeric sieving matrices specifically developed for this separation. These matrices, while effective, are costly and do not provide adequate resolution of STR DNA fragments in capillaries with shorter effective separation lengths, increasing the time required to accomplish the separation and minimizing the potential extrapolation to other miniaturized platforms. As the forensic community looks toward next generation microchip technology as a means of processing casework more rapidly, new sieving polymers need to be evaluated for utilization in this platform. The research presented here describes the assessment of commercially-available polymeric sieving matrices for STR analysis, with consideration given to feasibility of incorporation into a microdevice. Polymer composition, molecular weight, and concentration were evaluated, along with an assessment of the effects of buffer composition, separation temperature, and capillary length. These variables were evaluated individually or collectively on the ability to resolve STR DNA fragments and the reproducibility of the separations and the results compared to a proprietary commercial product. A 600,000 Da MW poly(ethylene oxide) (PEO) solution at a 3% (w/v) concentration was determined to be the most suitable matrix for these separations. This polymer, in coated capillaries, provided highly robust and reproducible separations, with near baseline resolution of fragments having single base differences. Reductions in the temperature of the separation, from 60 degrees C to 40 degrees C, and the urea concentration of the buffer, from 7 M to 3.5 M, provided increased longevity of the PEO polymer for repeated separations. Comparison of this polymer with currently specified commercial products used for STR analysis showed that the optimized PEO matrix provided superior separations under all conditions tested. In addition, PEO could be utilized in shorter capillary systems, with a concurrent decrease in analysis time, highlighting its potential for use in shortened capillary or microdevice systems.  相似文献   
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