Forensic science international
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A new breath alcohol (ethanol) analyzer has been developed, which allows free exhalation, standardizes measured exhaled alcohol concentration to fully saturated water vapor at a body temperature of 37 degrees C (43.95 mg/L) and includes a built-in self-calibration system. We evaluated the performance of this instrument by comparing standardized alcohol concentration in freely expired breath (BrAC) with arterial (ABAC) and venous (VBAC) blood alcohol concentrations in fifteen healthy volunteers who drank 0.6 g of alcohol per kg body weight. The precision (coefficient of variation, CV) of the analyzer based on in vivo duplicate measurements in all phases of the alcohol metabolism was 1.7%. ⋯ We conclude that this new breath analyzer using free exhalation has a high precision for in vivo testing. The BrAC reflects very accurately ABAC in the post-absorption phase and substantially well in the absorption phase and thereby reflects the concentration of alcohol reaching the brain. Our findings highlight the magnitude of arterio-venous differences in alcohol concentration and support the use of breath alcohol analyzers as a stand-alone test for medical and legal purposes.
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The present study was aimed at demonstrating the diffusion of sea water or freshwater into the bloodstream as a consequence of water aspiration due to drowning. The study was carried out on 42 study group subjects who died by drowning in salt water (20 cases) and freshwater (22 cases) and 30 control group subjects who died from causes other than drowning. For 25 cases we obtained water samples from the aquatic locations where the victims were found. ⋯ Blood cultures from RV, FV, and FA showed various patterns of faecal bacteria presence. The analysis of 25 water samples from the aquatic locations where the victims were found showed the presence of FC and FS bacteria. Blood cultures from the 30 control subjects uniformly proved the absence of faecal bacteria.
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Child abuse by burning comprises 6-20% of all child abuse cases, but misdiagnosis may arise in cases of some medical conditions. We present two cases of suspected inflicted burns, later diagnosed as staphylococcal scalded skin syndrome (SSSS). In case 1, a 6-month-old girl was referred to hospital for small round ulcerations on the face and abdomen, resembling cigarette burns. ⋯ Child abuse was finally ruled out, and SSSS was diagnosed. In cases of suspected inflicted child burns, observation during hospitalization may reveal changes in lesions, ascribed to the evolution of medical conditions. SSSS diagnosis is mainly based on clinical grounds but, if the suspicion of abuse remains, isolation and phage typing of Staphylococcus aureus from nasal, pharyngeal or cutaneous swabs may confirm the diagnosis.
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This article reports on the electric network frequency criterion as a means of assessing the integrity of digital audio/video evidence and forensic IT and telecommunication analysis. A brief description is given to different ENF types and phenomena that determine ENF variations. In most situations, to reach a non-authenticity opinion, the visual inspection of spectrograms and comparison with an ENF database are enough. ⋯ The stability of the ENF over geographical distances has been established by comparison of synchronized recordings made at different locations on the same network. Real cases are presented, in which the ENF criterion was used to investigate audio and video files created with secret surveillance systems, a digitized audio/video recording and a TV broadcasted reportage. By applying the ENF Criterion in forensic audio/video analysis, one can determine whether and where a digital recording has been edited, establish whether it was made at the time claimed, and identify the time and date of the registering operation.
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Drug screening methods were developed to detect alprazolam, clobazam, clonazepam, diazepam, midazolam, oxazepam, temazepam, triazolam, zopiclone, and selected metabolites in human hair and nail samples employing liquid-liquid extraction and tandem liquid chromatography-mass spectrometry (LC-MS-MS). Hair and nail samples were obtained from patients who had recently discontinued or were currently prescribed one or more of the targeted drugs. ⋯ The analytical run time was 8-10min. Results of the hair analysis of a DFSA victim are also presented.