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61.
This work presents the validation of a new immunological assay, the One-Step™ enzyme-linked immunosorbent assay (ELISA) tests from International Diagnostic Systems Corp. for the screening of drugs of abuse (cannabis, amphetamines, opiates, and cocaine) in human hair, with subsequent GC–MS confirmation. After decontamination and segmentation into small pieces, 50 mg of hair sample were incubated in 1 ml of methanol during 16 h at 40 °C. A 100 μL aliquot was collected and evaporated to dryness in presence of 100 μL of methanol/hydrochloric acid (99:1, v/v) to avoid amphetamines loss. The dried extract was dissolved in 100 μL of the “sample and standard diluent” solution included in the kit. This solution was submitted to analysis according to the recommended instructions of the manufacturer. During the validation phase, GC–MS confirmations were conducted according to our fully validated and published methods for opiates, cocaine, cannabis, and amphetamines determinations in hair. In a last development step, these procedures were slightly modified to directly confirm ELISA results by GC–MS using the methanolic extract. Ninety-three specimens were simultaneously screened by the ELISA tests (103 for tetrahydrocannabinol (THC)) and confirmed by GC–MS. Twenty were found positive for cannabis (THC: 0.10–6.50 ng/mg), 21 for cocaine (0.50–55.20 ng/mg), 24 for opiates (6-acetylmorphine (6-AM): 0.20–11.60 ng/mg, MOR: 0.20–8.90 ng/mg, codeine (COD): 0.20–5.90 ng/mg), and 13 for amphetamines (AP: 0.20 and 0.27 ng/mg, methamphetamine (MAP): 0.30 and 1.10 ng/mg, methylenedioxymethamphetamine (MDMA): 0.22–17.80 ng/mg). No false negative results were observed according to the Society of Hair Testing's (SoHT) cutoffs (0.5 ng/mg for cocaine, 0.2 ng/mg for opiates and amphetamines, and 0.1 ng/mg for THC). The One-Step™ ELISA kits appear suitable due to their sensitivity and specificity for drug of abuse screening in hair. This technology should find interest in workplace drug testing or driving license regranting, especially when many samples have to be tested with a high rate of negative samples, as ELISA is an easy and high-throughput method.  相似文献   
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Cyanide is a powerful chemical asphyxiant found in some forensic cases following voluntary (suicide) or involuntary ingestion (fire, accidental exposure). A quantification method for cyanide that is specifically suited to post-mortem forensic purposes was developed. Determination was performed by headspace gas chromatography coupled to mass spectrometry using a GS-GASPRO column on an HP-6890 gas chromatograph with an HP-5973N mass detector. The biological sample was treated with an internal standard, frozen, glacial acetic acid was added and the sample was then incubated at 60°C for 15min. The headspace was sampled with a disposable syringe, and analyzed to quantify hydrogen cyanide. Isotopically labeled cyanide ((13)C(15)N) was used as the internal standard to minimize matrix effect and sampling error. The method produced an extended linear dynamic range (0.07-50μg/mL), and a method detection limit of 0.02μg/mL. Identical calibration curves were obtained when blood, gastric contents and aqueous solutions were used as the calibration standard matrix. This method was also successful in quantitating cyanide in gastric contents, one of the most variable biological fluids. The method has been validated and is being used for current forensic cases such as fire victims and suicides.  相似文献   
64.
In forensic science, there is a strong interest in determining the post-mortem interval (PMI) of human skeletal remains up to 50 years after death. Currently, there are no reliable methods to resolve PMI, the determination of which relies almost exclusively on the experience of the investigating expert. Here we measured (90)Sr and (210)Pb ((210)Po) incorporated into bones through a biogenic process as indicators of the time elapsed since death. We hypothesised that the activity of radionuclides incorporated into trabecular bone will more accurately match the activity in the environment and the food chain at the time of death than the activity in cortical bone because of a higher remodelling rate. We found that determining (90)Sr can yield reliable PMI estimates as long as a calibration curve exists for (90)Sr covering the studied area and the last 50 years. We also found that adding the activity of (210)Po, a proxy for naturally occurring (210)Pb incorporated through ingestion, to the (90)Sr dating increases the reliability of the PMI value. Our results also show that trabecular bone is subject to both (90)Sr and (210)Po diagenesis. Accordingly, we used a solubility profile method to determine the biogenic radionuclide only, and we are proposing a new method of bone decontamination to be used prior to (90)Sr and (210)Pb dating.  相似文献   
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A 67‐year‐old man was found dead, at his home. On external examination, we found a voluminous purplish black ecchymosis of the anterior neck area. On internal examination, we found a voluminous epiglottis hematoma completely obstructing the upper airway. It was associated with other sites of intra‐abdominal hemorrhage. Toxicological studies revealed the presence of warfarin at a concentration of 8.4 mg/L in peripheral blood, which supposes an INR well above 4.5. To conclude, we supposed death was due to asphyxia secondary to a spontaneous epiglottic hematoma caused by a high blood concentration of warfarin. Hemorrhage in the epiglottis is very rare. To our knowledge, our patient is the only case of “sudden death” reported with spontaneous epiglottic hematoma due to high blood concentration of warfarin. In forensic practice, an anterior neck ecchymosis, without trauma, may suggest hemorrhage into soft airway tissues. Pathology findings make it possible to exclude exogenous trauma.  相似文献   
67.
One of the goals of the Forensic Anthropology Society of Europe (FASE) is to map the existing education and practice opportunities in the field of forensic anthropology in order to support the development of the discipline and to optimize the training courses provided by the Society. To address this goal, an online questionnaire was sent to European and South African practitioners of forensic anthropology and related disciplines in 2016. The results of the questionnaire showed that the status and roles of forensic anthropologists vary depending on the national legal systems, education, and employment status of the practitioners. Despite the fact that the expertise of forensic anthropologists has been increasingly requested in a variety of investigations and the spectrum of tasks has become broader, including identification of living persons, specialized education in forensic anthropology is still restricted to a few graduate and postgraduate programs in European countries and to annual FASE courses.  相似文献   
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With regard to the law, estimating fetal age is essential to assess viability (after 20 weeks according to the WHO) and the proposed methods generally use long bone measurements. Here, we evaluated the accuracy of soft tissue maturational stage and compared it with long bone measurements. First, eight kinds of tissues or organs from 448 fetuses with known medical history were studied (macroscopically or histologically). We clearly demonstrated that adrenal glands and skin were very good age indicators, because some characteristics appeared only after 20 weeks. We established a linear regression with a 95% confidence interval of +/- 2.9 weeks. Second, we applied our original formula using femur measurement and we combined soft tissues and bones in a multiparametric regression. The confidence interval was reduced to +/- 2.5 weeks. We conclude that the pathologist must use both histological and anthropometric data to determine fetal age as accurately as possible.  相似文献   
70.
Interests and information in referendum voting: An analysis of Swiss voters   总被引:1,自引:0,他引:1  
Abstract. Referendums impose considerable informational demands on voters. Recent theoretical and empirical research has emphasized the different shortcuts and heuristics they may employ in deciding how to vote. Relying on a substantial series of votes at the national level in Switzerland, we provide empirical tests on how Swiss voters cope with the informational demands in referendum voting. We combine simple heuristics, like partisan cues and endorsements, with indicators of instrumental interests to explain citizens' choices in a series of votes.  相似文献   
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