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Comparing skeletal structures between antemortem and postmortem chest radiographs is widely used by forensic specialists from many disciplines to positively identify unknown decedents. However, validity assessments of this method have been fairly limited. This study had three objectives: 1) to quantify the reliability of ante- and postmortem chest radiograph comparison for decedent identification; 2) to identify useful radiologic features supporting decedent identification; and 3) to recognize sources of error in decedent identification related to use of comparative radiographs. A forensic pathologist, a forensic anthropologist, and two radiologists participated in the study. Our results showed that chest radiograph comparisons proved reliable, if basic decedent information was provided, and antemortem and postmortem radiographs were adequately positioned and exposed. A "morphological approach" using normal anatomical structures for comparison may provide the most efficient method for accurate identification. 相似文献
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Samyn N De Boeck G Wood M Lamers CT De Waard D Brookhuis KA Verstraete AG Riedel WJ 《Forensic science international》2002,128(1-2):90-97
In a double-blind placebo controlled study on psychomotor skills important for car driving (Study 1), a 75 mg dose of +/- 3,4-methylenedioxymethamphetamine (MDMA) was administered orally to 12 healthy volunteers who were known to be recreational MDMA-users. Toxicokinetic data were gathered by analysis of blood, urine, oral fluid and sweat wipes collected during the first 5h after administration. Resultant plasma concentrations varied from 21 to 295 ng/ml, with an average peak concentration of 178 ng/ml observed between 2 and 4h after administration. MDA concentrations never exceeded 20 ng/ml. Corresponding MDMA concentrations in oral fluid, as measured with a specific LC-MS/MS method (which required only 50 microl of oral fluid), generally exceeded those in plasma and peaked at an average concentration of 1215 ng/ml. A substantial intra- and inter-subject variability was observed with this matrix, and values ranged from 50 to 6982 ng/ml MDMA. Somewhat surprisingly, even 4-5h after ingestion, the MDMA levels in sweat only averaged 25 ng/wipe. In addition to this controlled study, data were collected from 19 MDMA-users who participated in a driving simulator study (Study 2), comparing sober non-drug conditions with MDMA-only and multiple drug use conditions. In this particular study, urine samples were used for general drug screening and oral fluid was collected as an alternative to blood sampling. Analysis of oral fluid samples by LC-MS/MS revealed an average MDMA/MDEA concentration of 1121 ng/ml in the MDMA-only condition, with large inter-subject variability. This was also the case in the multiple drug condition, where generally, significantly higher concentrations of MDMA, MDEA and/or amphetamine were detected in the oral fluid samples. Urine screening revealed the presence of combinations such as MDMA, MDEA, amph, cannabis, cocaine, LSD and psilocine in the multiple-drug condition. 相似文献
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The Skinny on Body Dissatisfaction: A Longitudinal Study of Adolescent Girls and Boys 总被引:3,自引:1,他引:3
The present study tested whether theoretically derived risk factors predicted increases in body dissatisfaction and whether gender moderated these relations with data from a longitudinal study of 428 adolescent girls and boys because few prospective studies have examined these aims, despite evidence that body dissatisfaction increases risk for various psychiatric disturbances. Body dissatisfaction showed significant increases for girls and significant decreases for boys during early adolescence. For both genders, parental support deficits, negative affectivity, and self-reported dietary restraint showed significant relations to future increases in body dissatisfaction. Ideal body internalization and body mass index did not demonstrate significant relations to future increases in body dissatisfaction; peer support deficits showed a marginal relation to this outcome. Gender did not moderate these relations, despite adequate power to detect interactive effects.
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Sarah Kate BearmanEmail: |
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