1,720,971 research outputs found
Comparative postmortem blood alcohol concentrations in cardiac and peripheral blood: a case series
No full textBlood is an exceptionally important tissue in forensic toxicology. Determination of blood alcohol concentration (BAC) is conducted in gas chromatography with flame ionization detection using the headspace technique (HS-GC-FID). Whenever possible, postmortem blood from two districts, cardiac and peripheral, should be drawn at each autopsy. Because of the high probability of contamination, blood from the thoracic and abdominal cavities should be avoided unless no other blood matrix is available. In postmortem analysis for the determination and quantification of exogenous substances, cardiac blood tends to be more prone to redistribution than peripheral blood. Postmortem redistribution (PMR) is a phenomenon whereby the concentration of exogenous substances undergoes alterations in the body after death. The underlying mechanism is complex and still unclear; moreover, the degree of PMR can vary depending on the districts and tissues involved. Analyses conducted on peripheral (e.g., femoral) blood show greater reliability in terms of results than cardiac blood
Identification of N-piperidinyl etonitazene in alternative keratinous matrices from a decomposing cadaver
No full textThis short report describes research on N-piperidinyl etonitazene, also known as etonitazepipne, in keratinous matrices (hair and nails) after death related to a suspected opioid overdose. Etonitazepipne belongs to the family of benzimidazole opioids, a class of new synthetic opioids that has penetrated the illicit drug market. Analysis in the case under study showed the presence of etonitazepipne in both hair and nails, confirming that the substance accumulates in the body with repeated intake
A study into the nature and extent of polydrug use in driving recidivism behavior
No full textbjective: Polydrug use has become a frequent pattern of drug consumption in Europe, and this is considered a particularly dangerous risk factor for impaired driving. In Italy, persons whose license has been revoked or suspended due to the use of psychoactive drugs can reapply for a new driving license, depending on the judgment of the relevant local medical committee (CML). To regain a revoked license, offenders must remain drug free throughout an observation period. An important problem with enforcement of impaired driving is recidivism. The aim of the present study is to analyze the influence of polydrug use on driving recidivism. Method: We report the findings of several years’ experience at the forensic toxicology laboratory of the University of Macerata. Hair samples collected over a 7-year period by the CML from drug users were analyzed for cocaine, opiates, and cannabis using gas chromatography–mass spectrometry. Results: Three hundred thirty-five of the tested subjects were recidivists. Recidivism was more frequent among monodrug users (81%) compared with polydrug users (19%), but logistic regression showed that polydrug use is certainly a risk factor for recidivism compared to monodrug use (odds ratio [OR] = 1.99). The sex and age distribution of recidivist subjects showed a strong predominance of males in both groups, but there were no sex differences. There were more recidivist polydrug users than recidivist monodrug users in the younger age groups (OR = 2.012). Cocaine use was most prevalent in the recidivist monodrug group. All drugs analyzed were demonstrated to be a risk factor for recidivism among monodrug users, whereas only the cocaine and cannabis combination was shown to be a risk factor for recidivism among polydrug users (OR = 1.65 versus cocaine; OR = 1.30 versus Δ9-tetrahydrocannabinol). Almost all polydrug users became monodrug users, and cocaine was the most frequently detected drug in the subsequent test during the monitoring phase. Conclusions: Our results show that polydrug use increases the risk of impaired driving recidivism and represents a considerable threat to road safety
A study of free and total morphine in heroin death of chronic users
Full text linkHeroin is a widely abused substance, involved in a large number of deaths. It has been seen that long-term exposure to street heroin results in an increase in morphine glu- curonide metabolites. This suggested us that there might be a relationship between blood morphine metabolites concentrations and heroin-related deaths. In particular, the concen- tration of morphine glucuronide metabolites could be higher in delayed heroin-related death compared to rapid heroin-related deaths. To evaluate this hypothesis, 53 forensic autopsies of heroin-related death collected between 2016 and 2022 were divided into two groups: chronic user (CU) and non-chronic users (NCU), on the basis of the morphine positivity in hair. The dif- ference of blood free morphine concentrations (FM), blood total morphine concentrations (TM) in blood and bile morphine concentrations (BTM), in the two groups were statistically analysed. Also, the FM/TM ratios were calculated. FM was used to analyse the difference of immediate, subacute and delayed deaths in the two groups. The results showed that the median FM value in the CU group was non-statistically higher than in NCU one. The CU group showed a significantly higher median TM and BTM values, but a significantly lower FM/TM value than in NCU group. Furthermore, the CU group showed a significantly higher percentage of FM in delayed deaths than NCU group. In conclusion, measurements of blood variables indicate a shift in morphine metabolites that could be involved in heroin-related death among chronic users, possibly being a risk factor for delayed causes of death of drug users
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Comparative analysis between CDT in serum and Ethyl glucuronide in hair to define the best reliable tool for the diagnosis of alcohol abuse
Full text linkThe increase in alcohol consumption in society has not only led to a number of medical issues but has also become a matter of considerable legal importance. Thus, there is both scientific interest and the necessity to diagnose alcohol abuse in the application of the provisions of the law through laboratory tests that ensure maximum objectivity. The purpose of this work is to study and compare the diagnostic performance of two of the main markers of alcohol abuse, serum carbohydrate-deficient transferrin (CDT) and Ethyl glucuronide (EtG) in a group of 336 driving under the influence (DUI) of alcohol offenders. Thus, it is possible to establish the best marker of alcohol consumption in order to assess the fitness to drive of DUI subjects.EtG was detected in 55 hair samples, while CDT was detected in 5 blood samples. Of the EtG-positive subjects 96,4% had CDT values below the cut-off. While CDT refers to an alcohol consumption of approximately the previous 10 days, EtG allows to detect an excessive alcohol consumption of the last few months. Because of these two different time-windows, EtG proves to be more reliable, since it is more difficult for subjects to change their drinking practice to test negative to toxicological analysis. The determination of Ethyl glucuronide on hair matrix is a valuable tool for the diagnosis of alcohol abuse, with high sensitivity and specificity and certainly greater reliability than traditional markers such as CDT, being a direct marker of alcohol consumption
Detection of Three Opioids (Morphine, Codeine and Methadone) and Their Metabolites (6-Monoacetylmorphine and 2-Ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine) in Larvae of <i>Lucilia sericata</i> Species by UHPLC-TF-MS and Validation
Full text linkInsects on corpses could be a useful tool for the detection of exogenous substances such as drugs of abuse. The identification of exogenous substances in carrion insects is critical for proper estimation of the postmortem interval. It also provides information about the deceased person that may prove useful for forensic purposes. High-performance liquid chromatography coupled with Fourier transform mass spectrometry is a highly sensitive analytical technique that can identify substances even at very low concentrations, such as in the case of searching for exogenous substances in larvae. In this paper, a method is proposed for the identification of morphine, codeine, methadone, 6-monoacetylmorphine (6-MAM) and 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) in the larvae of Lucilia sericata, a common carrion fly widely distributed in temperate areas of the world. The larvae, which were reared on a pig meat substrate, were killed once they reached their third stage by immersion in hot water at 80 °C and aliquoted into 400 mg samples. The samples were fortified with 5 ng of morphine, methadone and codeine. After solid-phase extraction, the samples were processed with a liquid chromatograph coupled to a Fourier transform mass spectrometer. This qualitative method has been validated and tested on larvae from a real case. The results lead to the correct identification of morphine, codeine, methadone and their metabolites. This method could prove useful in cases where toxicological analysis must be conducted on highly decomposed human remains, where biological matrices are very limited. Furthermore, it could help the forensic pathologist to better estimate the time of death, as the growth cycle of carrion insects can undergo changes if exogenous substances are taken
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