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To answer the question whether a negative result of gas chromatographic blood analysis for components of chemical mace proves that no or at most only slight tear gas exposure can have occurred, animal experiments were carried out. In the blood of 10 guinea pigs, which were exposed to the contents of chemical mace for 1--6 h, the solvants 1,1,2-trichloro-1,2,2-trifluorethane (freon 113) and 1,1,1-trichloroethane could easily be detected--even 23 h after the end of exposure or after a storage of the blood samples for 18 weeks--whereas the lacrimator chloracetophenone (CN) could not be found at all. In vitro experiments showed that CN relatively quickly reacts with components of blood. Therefore, blood samples should be analyzed for CN after withdrawal as soon as possible. In case of inhalation of the contents of chemical mace, i.e., after the comparatively mildest form of CN application, most probably no traces of the lacrimator at all can pass into the blood due to the quick reaction of CN with proteins of the respiratory surface of the lung. 相似文献
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Anthony M. Orum 《Political Behavior》1979,1(1):31-52
In the past three different paradigms or, more loosely, frames of reference, have been used by students of politics to interpret various dimensions of mass political participation. Each of these, which are referred to as the political socialization, the group interests and beliefs, and the political party/organization paradigms, has received empirical support for its scheme of interpretation; yet recent political events also suggest that these frames of reference may be inadequate, and may need to be complemented, if not replaced, by other schemes. The present paper outlines one such scheme, drawing upon recent writings on social networks and social influences on political participation. It relies on the metaphor of a political arena, and proposes two simple propositions to account both for conventional and unconventional participation in this arena.An earlier version of this paper was delivered at the Annual Meetings of the Society for the Study of Social Problems, New York, NY, August 1976. 相似文献
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Kelly?N.?GravesEmail author Maria?E.?Fernandez Terri?L.?Shelton James?M.?Frabutt Amanda?P.?Williford 《Journal of youth and adolescence》2005,34(4):379-387
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 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