Forensic Science International: Reports最新文献

Burned human remains have been studied by both forensic anthropologists and bioarchaeologists to understand how fire impacts and alters bone in different scenarios. Heat-induced changes can occur including differences in colour and shrinkage, where the extent of the latter varies in different studies. The current study aimed to bring information regarding this topic and to observe how the individual’s biological sex and age at death impact shrinkage. The variability of shrinkage was analysed, relating to temperature and duration of burning. The sample comprised of the patellae of 32 individuals (18 [56.3 %] females and 14 [43.8 %] males) with age at death between 60 and 93 (age grouped in decades) from the sub-collection of experimentally burned skeletons, part of the 21st Century Identified Skeletal Collection (ISC/XXI). The right patellae were subjected to experimental burning at different temperatures and durations using an electric muffle furnace. Both the right and left patellae had three measurements taken, maximum height, maximum thickness and maximum width, with a digital calliper. The shrinkage percentage was higher in males and among the younger individuals (60–79 years old of both sexes). The values of standard deviation were high which indicates high variability. Shrinkage occurred at every temperature with bigger values observed in the patellae that had been subjected to temperatures over 800ºC. However, three patellae showed an increase in size at temperature under 800ºC. These findings align with previous studies where a non-linear correlation between shrinkage and exposure duration was found. It is essential to underscore that the percentage of shrinkage exhibits substantial variability even under identical temperature and duration conditions, highlighting the critical significance of meticulous experimental design and thorough analysis.

Heroin use is responsible for many drug-related deaths, so the determination of its biomarkers, except for 6-acetylmorphine, in biological samples, is of particular concern in toxicological laboratories worldwide, for a better investigation of these cases. Th use of 6-acetylmorphine as a heroin biomarker has some limitations due to its rapid bioconversion to morphine within a few hours, especially in blood samples. The need for new indirect biomarkers, like the ones that come from the processing of opium during the clandestine production of heroin, becomes imperative. A GC/MS method was developed and validated for the determination of meconin, thebaine, papaverine, acetylcodeine and noscapine, along with morphine, codeine and 6-acetylmorphine, in different biological samples of heroin users. For all analytes and all individual biological samples, the LOD and LOQ were 2.00 and 5.00 ng/mL, respectively, the calibration curves were linear (R²≥0.991) from 5.00 to 500.0 ng/mL, and absolute recoveries were higher than 91.9 %. The method was applied during the toxicological investigation of 34 forensic cases after positive immunoassay screening for opiates. The results indicate that meconin is the most frequently detected indirect biomarker of heroin use, as it was found in 91.2 % of all cases, whilst in 23.5 % of them no 6-acetylmorphine was detected. Papaverine was found in 67.6 % of all cases and is considered to be the second most important indirect biomarker of heroin use. The establishment of detecting meconin and papaverine in biological materials in parallel with the detection of morphine, codeine and 6-acetylmorphine can contribute to more conclusive results concerning heroin use in forensic cases.

One of the primary goals of forensic laboratories performing DNA recovery and profiling is obtaining a high-quality DNA extract from crime scene samples. This is largely dependent on the sensitivity and reliability of the DNA extraction chemistry utilised, as well as the liquid handling and contamination minimisation techniques employed. Automation of DNA extraction methods on large liquid handling platforms allows high-throughput laboratories to apply sensitive chemistries to reliably process a large number of samples, while minimising manual processes and cross-contamination.

This study describes the first known implementation of the PrepFiler™ Automated Forensic DNA Extraction Kit on a Tecan Fluent® Gx 1080 Automation Workstation. Two Workstations were customised with the addition of novel “Safe Pipetting Modules” to eliminate sample crossover between wells, which is important in a forensic biology setting to reduce inadvertent DNA transfer. A comparison of DNA extraction efficiency between an optimised PrepFiler™ method and the DNA IQ™ System performed on a Perkin Elmer Janus® Integrator platform showed the optimised PrepFiler™ method consistently extracted a higher yield of DNA from a range of blood inputs, as well as blood and buccal swabs. The PrepFiler™ chemistry also more efficiently removed humic acid and haematin, reducing subsequent PCR inhibition. The subsequent implementation of the optimised PrepFiler™ method onto the Tecan Fluent® Gx workstations showed a further increase in sensitivity, with no evidence of DNA cross-contamination observed. However, the optimised PrepFiler™ method encountered difficulties extracting DNA from fabric substrates, with the PrepFiler Express™ chemistry extracting higher yields on the cartridge-based AutoMate Express™ System.

Overall, this study demonstrated the Tecan Fluent® Gx 1080 Automation Workstation is a sensitive, reliable and robust method for DNA extraction using the PrepFiler™ Automated Forensic DNA Extraction Kit, and the addition of the novel Safe Pipetting Module makes this platform an attractive option for forensic biology laboratories where minimising inadvertent DNA transfer is of paramount importance.

One crucial aspect of a forensic procedure is sex estimation during individual identification. Hand and its remains are usually among the common body parts found in scenes of mass disasters during forensic investigations. Hand outlines are also important in several biomedical fields such as prosthetics, plastic surgery, and ergonomics. This cross-sectional study was done to investigate sexual dimorphism and discriminate sex using hand and hand print dimensions of 283 male and 317 female subjects who were randomly selected. Bare hand measurement and bilateral hand prints were obtained using Vernier caliper, inked pad, and A4 plain paper. Data obtained were analyzed using SPSS version 23.0 IBM. Sexual dimorphism in all the hand dimensions and prints of both hands were observed. The binary logistic regression model showed that in the left hand, bare left-hand breadth (BLHB) was the single best variable to discriminate sex with a percentage accuracy of 69.5 %. Bare right-hand breadth (BRHB) was the best predictor in the right hand with a percentage accuracy of 71.8 %. The predicted probabilities of the binary logistic model (BLR) for the variables that contributed best to the prediction were analyzed using the receiver operating characteristic (ROC) curve. It was observed that the BLHB and BRHB had the highest area under the curve (above 0.5) in the hand and print variables respectively. Sexual dimorphism and sex determination were established in this study using hand dimensions and prints. The BLHB and BRHB were the best sex determinants in this study. Although the accuracies of sex estimation from both hands in this study are low, it does confirm and support previous reports of handbreadth being the best variable for sex estimation.

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As humanity advances into a space-faring species, the risk of injury by multiple means and intentions will follow. Expanding understanding of how forensic science adapts to extraterrestrial environments is a novel and inevitable expansion into the next forensic frontier. This study considers the unique challenges of bloodstain pattern analysis in microgravity environments. Specifically, observation in novel experimentation aboard a parabolic flight research airplane which yielded fluid dynamic behaviors in a microgravity environment that provides practical understanding of Earth-based and off-world bloodstain applications.

This is a Letter to the Editor in response to Kariks J. Diaphragmatic muscle fibre necrosis in SIDS. Forensic Sci Int. 1989 Dec;43(3):281–91. doi: 10.1016/0379-0738(89)90156-4. PMID: 2613142.