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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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The DNA dragnet     
Ripley A 《Time》2005,165(4):39-40
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A collaborative study on Raman spectroscopy was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on three dyed fibers: two red acrylics and one red wool. Raman instruments from six different manufacturers were tested as well as nine different laser wavelengths ranging from blue (lambda = 458 nm) to near infrared-NIR (lambda = 1064 nm). This represents the largest comparison study of Raman analytical parameters carried out on identical fiber samples. For the chosen fiber and dye samples, red lasers (lambda = 633 and 685 nm) gave the poorest spectral quality whereas blue (458 nm), green (514 nm) and near infrared lasers (785, 830 and 1064 nm) provided average results. Blue (488 nm) and green lasers (532 nm) globally gave the best quality spectra. Fluorescence problems were often encountered with some of the excitation wavelengths and therefore a flexible Raman instrument equipped with different lasers can be recommended to measure forensic fiber samples. The instrument should also be equipped with a Raman microscope in order to be able to focus on a single fiber. This study shows that Raman spectroscopy usually enables the identification of the main dye present in a colored fiber; however, minor dye components are much more difficult to detect. SERRS (Surface Enhanced Resonance Raman Scattering) techniques give an improvement of the dye's spectral intensity but no spectral improvement was observed for the two red acrylic and red wool fibers tested.  相似文献   
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Carbon monoxide (CO) poisoning as a cause of death is well documented in industrialized countries. The objective of this study was to compare demographic data in deaths due to accidents (in fires) and suicides in the same population between 1988 and 1998. Furthermore, the potential effect of a community wide education effort regarding safety in the home was assessed. Postmortem reports were reviewed for all deaths examined at the Office of the Cuyahoga County Coroner in Cleveland, OH, USA. During the study period, there were 209 accidental deaths due to fires in the home (6.5% of all accidents in the home) and 182 CO deaths by suicide (9.8% of all suicides). Demographic characteristics of the two groups differed: while males represented the majority of cases in both groups (55% of accidents, 70% suicides), race specific death rates were higher for whites than blacks (18/100,000 white, 3/100,000 black) in suicides compared with 29/100,000 deaths for blacks and 11/100,000 for whites in accidental cases. Fire deaths were prevalent in the young (0-9 years) and old (>60) whereas in the suicide group the age specific death rate was highest for those over 70 years. The majority of fire deaths occurred in the city of Cleveland but suicides were prevalent in the suburbs. More fire deaths occurred in December than any other month whereas more suicides occurred in April. In 1992, there was a community wide effort to provide free smoke detectors to residents in Cleveland. In 1992, there were 4.2/100,000 fire deaths in the city. This decreased to 0.6/100,000 in 1996, increased to 1.2/100,000 in 1997 followed by a decrease to 0.8/100,000 in 1998. This suggested that the program may have aided in decreasing these types of deaths. Deaths due to fires in the suburbs were <1/100,000 throughout the study period.  相似文献   
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