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Clauwaert KM Van Bocxlaer JF Lambert WE De Leenheer AP 《Forensic science international》2000,110(3):157-166
Hair samples of eight postmortem cases were analyzed in segments of 1 to 3 cm for cocaine, benzoylecgonine and cocaethylene. Samples were prepared for analysis by digestion in 0.1 M HCl and subsequent extraction with mixed-mode solid-phase extraction columns. Measurement was made by reversed-phase, narrow-bore HPLC and fluorescence detection using two laboratory-made internal standards. The concentrations were in the region of 0.29-316 ng/mg of hair for cocaine, 0.43-141 ng/mg of hair for benzoylecgonine and 0.93-1.83 ng/mg of hair for cocaethylene. All eight investigated cases had cocaine-positive segments. In six of the cases, all segments were positive, suggesting regular cocaine use and two showed in-between negative segments indicating an interruption or a change of the abuse intensity. The results showed a second, remarkable observation, i.e. enormous concentration differences (factor >150) for both cocaine and benzoylecgonine between the different subjects. Furthermore, interindividual cocaine/benzoylecgonine ratios ranged from 0.02 to 8.43. We believe these observations could in part be attributed to both some of the still existing limitations in the analytical approach(es), especially the mandatory hair washing steps, and in our still too limited knowledge of the hair incorporation processes. Nevertheless, in some cases, segmental analysis proved to be an important tool to distinguish, together with postmortem examination, deadly chronic abuse from single acute drug overdosage. 相似文献
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Massonnet G Buzzini P Jochem G Stauber M Coyle T Roux C Thomas J Leijenhorst H Van Zanten Z Wiggins K Russell C Chabli S Rosengarten A 《Journal of forensic sciences》2005,50(5):1028-1038
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
47.
Although representative payeeship is prevalent among people with mental illness and shows promise to positively influence
clinically relevant outcomes, research also suggests this legal mechanism could be implemented in ways that are problematic.
The current study examined whether family representative payeeship was associated with elevated risk of family violence perpetrated
by persons with severe mental illness (SMI). Data were collected every 4 months for 1 year in structured interviews with N
= 245 persons with SMI who received disability benefits. Multivariate analyses showed that substance abuse, history of violence,
frequency of family contact, and family representative payeeship were associated with elevated odds of family violence. Analyses
also showed family contact and family representative payeeship had a cumulative effect on increasing the predicted probability
of family violence (controlling for covariates such as violence history and substance abuse). The data shed light on the potential
for family representative payeeship to be associated with increased risk of interpersonal conflict and violence in SMI. 相似文献
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This study reports on the reduction in violent offending in a population of serious and violent juvenile offenders following an intensive institutional treatment program. The treatment group (N=101) is compared to a similar group that was assessed but not treated (N=147). All youth were sent to the program from a juvenile corrections institution where they had received the customary rehabilitation services. The results show a significant reduction in the prevalence of recidivism in the treated group after controlling for time at risk in the community and other covariates. The effects of non-random group assignment were reduced by including a propensity score analysis procedure in the outcome analysis. Untreated comparison youth appeared to be about twice as likely to commit violent offenses as were treated youth (44% vs. 23%). Similarly, treated youth had significantly lower hazard ratios for recidivism in the in the community than the comparison youth, even after accounting for the effects of non-random group assignment. 相似文献
49.
Renita?R.?Glaser M.?Lee?Van.?Horn Michael?W.?ArthurEmail author J.?David.?Hawkins Richard?F.?Catalano 《Journal of Quantitative Criminology》2005,21(1):73-102
Prevention science has produced information about risk and protective factors that predict adolescent drug use and related problem behaviors. This paper investigates the Communities That Care Youth Survey that measures multiple risk and protective factors. Using a sample of 172,628 students who participated in surveys administered in seven states in 1998, analyses were conducted to test the factor structure of these risk and protective factors and to test the equivalence of the factor models across five racial/ethnic groups (African Americans, Asians or Pacific Islanders, Caucasians, Hispanic Americans, and Native Americans), four grade levels (6th, 8th, 10th, and 12th) and both gender groups. Results support the construct validity of the surveys risk and protective factor scales and indicate that the measures are equally reliable across males and females and five racial/ethnic groups. Implications of these findings for science-based prevention planning are discussed. 相似文献
50.
This study investigated to what extent abuse-related symptoms and family functioning are related to intra- or extrafamilial sexual abuse. One hundred adolescents (12 to 18 years old) were recruited shortly after disclosure of the abuse. Information from the participants was obtained through self-report questionnaires and a semistructured interview. Fifty-three percent of the adolescents reported clinically significant symptoms. Data did not support the idea that intrafamilial sexually abused adolescents report more symptoms than extrafamilial sexually abused adolescents. Type of abuse did not account for the differences and variety of reported symptoms or for differences in family functioning. Family functioning-in particular, lack of cohesion- was an independent contributor to internalizing trauma-related problems. 相似文献