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941.
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
942.
943.
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
944.
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
945.
Johnson RD Lewis RJ Canfield DV Dubowski KM Blank CL 《Journal of forensic sciences》2005,50(3):670-675
Specimens from fatal aviation accident victims are submitted to the FAA Civil Aerospace Medical Institute for toxicological analysis. During toxicological evaluations, ethanol analysis is performed on all cases. Care must be taken when interpreting a positive ethanol result due to the potential for postmortem ethanol formation. Several indicators of postmortem ethanol formation exist; however, none are completely reliable. The consumption of ethanol has been shown to alter the concentration of two major serotonin metabolites, 5-hydroxytryptophol (5-HTOL) and 5-hydroxyindole-3-acetic acid (5-HIAA). While the 5-HTOL/5-HIAA ratio is normally very low, previous studies using living subjects have demonstrated that the urinary 5-HTOL/5-HIAA ratio is significantly elevated for 11-19 h after acute ethanol ingestion. Recently, our laboratory developed and validated an analytical method for the simultaneous determination of both 5-HTOL and 5-HIAA in forensic urine samples using a simple liquid/liquid extraction and LC/MS/MS and LC/MS/MS/MS. In this previous work a 15 pmol/nmol serotonin metabolite ratio cutoff was established in postmortem urine, below which it could be conclusively determined that no recent antemortem ethanol consumption had occurred. In the current study this newly validated analytical method was applied to five ethanol-positive aviation fatalities where the origin of the ethanol present could not previously be conclusively determined. In four of the five cases examined the detected ethanol was demonstrated to be present due to postmortem microbial formation, and not consumption, even though some indication of ethanol consumption may have been present. 相似文献
946.
947.
Sexually dimorphic distinctions within the human thoracic area may include morphological as well as metric differences in the sternum and 4th rib. This research assesses the validity of a set of previously published measurements from chest radiographs and their use in contemporary forensic situations. The chest plates from 130 adult individuals of a known sample undergoing medico-legal post-mortem examination were examined at autopsy. Thoracic radiographs were taken using a Faxitron cabinet X-ray machine at 40 kV using Kodak Diagnostic Film Ready Pack X-Omat TL. Measurements were taken to the nearest millimetre using a sliding calliper. Logistic regression analysis of measurements of the sternum and 4th rib was undertaken to determine sex. Using 4th rib width and sternal area, sex was predicted at an accuracy of 95.8% for males and 90.3% for females. 相似文献
948.
Does sexual dimorphism in facial soft tissue depths justify sex distinction in craniofacial identification? 总被引:1,自引:0,他引:1
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
949.
950.