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James Garbarino Nancy Burston Suzanne Raber Robert Russell Ann Crouter 《Journal of youth and adolescence》1978,7(4):417-428
This article reports the first results of the three-year longitudinal study of the social maps of children beginning the transition to adolescence. This exploratory study is guided by Bronfenbrenner's conception of the ecology of human development, stressing the importance of a phenomenological orientation to development in the context of ecological transitions. The study focuses on characteristics of children's social networks (the web of relationships in which the individual is involved) as a function of neighborhood type, socioeconomic status, and level of physical maturation. The social heterogeneity of the social network (e.g., the relative salience of peers versus adults) is a primary concern. The child's and parent's perceptions of the network, of the people available to help the child, and the child's friends are compared within the context of ecological, socioeconomic, and maturational factors. The results (for 111 sixth-grade children from three contrasting neighborhood schools) shed some light on age segregation and the overall heterogeneity of the social environments of children facing the transition to adolescence. They provide a context and a baseline for the longitudinal study.A version of this paper was presented at the 85th annual convention of the American Psychological Association, San Francisco, August 25–30, 1977.Received his Ph.D. in human development and family studies from Cornell University in 1973. Principal interests are the ecology of social development and child maltreatment. 相似文献
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Nicole V. Lasky Bonnie S. Fisher Caitlin B. Henriksen Suzanne C. Swan 《Journal of school violence》2017,16(2):173-188
ABSTRACTDrugging victimization is an understudied phenomenon. This study examines the relationship between the campus party culture and drugging victimization. Campus party culture has been shown to influence risk of other types of victimization, and there is reason to believe it may also influence drugging victimization. Using three behavioral indicators of participation in the campus party culture—binge drinking, Greek life membership, and first-year student status—this study estimates the main effect of each indicator, and their interaction, on undergraduates’ rates of drugging victimization. Estimating a generalized linear model using a large random sample (N = 6,931) from three universities, results show that each party culture variable and their three-way interaction significantly influenced students’ rate of drugging victimization. Sorority members who were first-year students and binge drank at least once in the past month had significantly higher rates of drugging victimization compared to all other groups of students. 相似文献
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Kaitlin R. Prather M.S. Suzanne E. Towner M.S. Victoria L. McGuffin Ph.D. Ruth Waddell Smith Ph.D. 《Journal of forensic sciences》2014,59(1):52-60
The effect of substrate interferences from high‐density polyethylene (HDPE) on the ability to associate an ignitable liquid residue with the corresponding liquid standard, using statistical procedures, is demonstrated. Gasoline, kerosene, and lighter fluid, at three different evaporation levels, were spiked onto HDPE and subsequently burned to generate simulated ignitable liquid residues (ILRs). Samples were extracted using a passive headspace procedure and analyzed by gas chromatography–mass spectrometry. The total ion chromatograms were subjected to data pretreatment procedures prior to principal components analysis and Pearson product moment correlation. Using the combination of these statistical procedures, simulated ILRs were successfully associated with the corresponding liquid type, despite the presence of compounds inherent to the HDPE substrate, as well as those resulting from pyrolysis of the substrate. 相似文献
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Funded by the National Science Foundation and the National Nanotechnology Infrastructure Network (NNIN), this study asks qualitatively analyzes interviews with 48 nanoscientist users at four NNIN facilities. The main research questions were: (1) Do nanotechnologies pose unique social and ethical concerns?; (2) how are the risks associated with nanotechnology distributed among different human populations?; (3) what are specific policy steps that can be used to manage such risks? This study purposefully oversampled female scientists to correct for the historical underrepresentation of women in the nanotechnology workforce. By amplifying the voice of this science, technology, engineering, and mathematics (STEM) workforce minority, the policy discussion contained herein better reflects the concerns of the general population. The results, analyzed with the aid of qualitative data analysis software, yield interesting differences in risk characterization among the scientists and innovative policy suggestions for the nanoscience community and regulators alike. 相似文献
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A simple microfluidic device (MFD) has been developed to perform multiple color and crystal tests for controlled substance analysis. The MFD method uses less sample and reagents and generates less waste than traditional spot plate methods while performing several tests simultaneously. This methodology provides significantly more analytical information for a single sample analysis. The current generation device is the size of a microscope slide with four analytical channels: one for microcrystal tests and three for color tests. The optimized devices were subjected to a rigorous validation study using comparative replicate analyses and several operators. Target analytes were methamphetamine, amphetamine, cocaine, and oxycodone and color test reagents used were the Marquis, Simon, and cobalt thiocyanate. For the crystal tests, platinic chloride was used. The validation study showed the MFD's limits of detection to be in the picogram range. Positive tests results were observed in complex mixtures in which the controlled substance was present at concentrations of 5-10% (w/w). The microcrystal reagents showed greater sensitivity than color test reagents when used in the device. Reagent use and waste generation using the devices was 95% less that that used and generated using the traditional methods. The device performance was also shown to be operator independent. 相似文献