Forensic Sciences Research最新文献

In the field of forensic sciences, human teeth are used to identify individuals in cases involving unidentified bodies. In recent years, isotope analysis of tooth enamel has been increasingly employed to estimate birth year and place of birth. The enamel is formed between the prenatal period and childhood, and after the tooth crown is complete, it does not undergo additional growth. Therefore, the oxygen isotope composition of the enamel bioapatite is significantly influenced by the environmental conditions during these periods, including dietary habits and tap water consumption. In this study, we aimed to predict the places of birth of 65 Japanese individuals, whose places of birth were known, by analysing the oxygen isotope ratios in carbonates in the enamel bioapatite. The oxygen isotope ratio in bioapatite varied from a maximum value of -3.4‰ to a minimum of -8.76‰, indicating lower and higher values in cold and warm areas, respectively. Furthermore, a correlation was observed between the oxygen isotope ratios and the latitudes and average annual temperatures of the place of residence during enamel formation (correlation coefficients: -0.84 and 0.81, respectively). Oxygen isotope analysis of enamel bioapatite can help in determining the environmental conditions in the place of residence during enamel formation. Overall, oxygen isotope analysis can be useful in predicting the place of residence during enamel formation of individuals in Japan. Key Points  Oxygen isotope ratios in tooth enamel bioapatite were analysed to determine the birthplaces of Japanese individuals.The oxygen isotope ratio correlated with the latitude and average annual temperature of the place of residence during enamel formation.Oxygen isotope analysis can help in estimating the place of birth of individuals in Japan.

Short tandem repeats have been essential and fundamental genetic markers used in forensic individual discrimination and paternity testing since their discovery, especially those used in the Combined DNA Index System. Nevertheless, in cases of complex kinship identification, such as full-sibling, half-sibling, and uncle-niece relationships, the combined application of additional short tandem repeat loci is necessary to reach reliable identification conclusions. In this study, we evaluated the efficiency of an updated novel short tandem repeat genotyping system for kinship identification in the Eastern Chinese Han population. This 23-plex short tandem repeat system demonstrated strong discrimination power among individuals in the target population, with a combined power of discrimination and cumulative probability of exclusion of 1-2.107 1 × 10^-27 and 0.999 999 999 800, respectively. When 74 short tandem repeats were used and the threshold log₁₀(likelihood ratio) was set to 4, the system efficiency reached 0.999 9 and 0.707 3 for simulated full-sibling and half-sibling pairs, respectively. Furthermore, in two real secondary kinship identification cases, incorporation of the novel 23-plex short tandem repeat system increased the probabilities of the prior kinship hypotheses from 154.259 5 and 1 031.699 5 to 56 597.118 4 and 134 829.791 5, respectively, yielding reliable identification conclusions. Hence, it is evident that the novel 23-plex short tandem repeat system has notable potential as a tool for forensic kinship identification in the Eastern Chinese Han population and could serve as a complementary set of short tandem repeat loci for the identification of distant kinship.

This study evaluates the accuracy and reliability of the İşcan and Hartnett methods for estimating the age of adults based on rib analysis, using a sample of 127 pairs of ribs from a contemporary European population. The study employed a double-blind design with repeated measurements conducted by two observers. The İşcan method demonstrated a higher success rate, accurately assigning age in 62% of cases, compared to 38% for the Hartnett method. Both methods exhibited moderate intra- and interoperator agreement, as measured by Cohen's Kappa. A detailed statistical analysis, including logistic regression, revealed significant discrepancies in phase-assignment accuracy between the two methods. The İşcan method's success rate improved when prioritizing the highest observed phase, indicating potential for enhancing accuracy through strategic methodological adjustments. The findings underscore the importance of operator training and the need for consistent application of criteria. This research highlights the critical need for standardization in age estimation methods and suggests potential improvements for forensic and anthropological applications. The study contributes valuable insights into the strengths and limitations of widely used skeletal age estimation techniques, with implications for improving methodological consistency and accuracy in forensic investigations. Key points  Human age can be estimated through the study of the fourth rib in skeletal remains; the two most commonly used methods are those of İşcan and Hartnett.Both the İşcan and Hartnett methods showed moderate inter- and intraoperator agreement.The İşcan method exhibited significant overlap in age ranges, particularly in later phases, which can lead to underestimation of age.The findings emphasize the importance of extensive training for operators using these methods.

Full-sibling (FS) identification is a crucial aspect of kinship analysis. However, current FS identification methods need to be more accurate and effective for routine FS identification. In this study, the optimal cut-off values for FS identification by incorporating both the identical by state (IBS) and likelihood ratio (LR) methods under four different levels of error rates were assessed. The corresponding sensitivity, specificity, accuracy, and effectiveness were calculated for different numbers of short tandem repeats (STRs), ranging from 19 to 55. The identified cut-off values were validated using authentic pedigrees from the Han population in East China. It was determined that the cut-off values derived from the IBS method and LR method with an error rate below 0.01% were dependable and practical. The study also explored the impact of half-sibling relationships and the inclusion of reference relatives in FS identification. Currently, an updated technical specification for FS identification in China was released, serving as a valuable resource for FS testing in forensic applications.

Second level dactyloscopic markants (minutiae) are irregularities in the course of the friction ridge skin used for personal identification because of their high variability. Individual uniqueness is affected by the high number of minutiae and their random distribution within the friction ridge skin. The combination of various environmental factors, e.g., snow, soil environment, and direct sunlight, can affect the quality of fingerprints. The aim of this study was to analyze the influence of snow under two different conditions (natural snowfall and immersion in the snow) within various time intervals on fingerprints. A total of 265 groomed latent distal fingerprints were taken from a Caucasian male from Slovakia. Latent fingerprints were taken only from one participant, as the composition of sweat, i.e., the sweat-fat substance, varies from person to person, which could influence the results. Subsequently, obtained latent fingerprints were developed using small particle reagent. We evaluated the decrease in the number of minutiae on latent fingerprints exposed to the destructive influence of snow. The results confirmed that snow has a significant effect on the quality of latent fingerprints, as a decrease in the average number of minutiae on latent prints was observed after only 2 h of exposure to snow conditions. After snow exposure, usable fingerprints for identification decreased, whilst non-usable ones increased, with 53.33% of non-usable fingerprints resulting from natural snowfall exposure. After exposure of latent fingerprints to snow immersion, 98.13% of non-usable fingerprints were found. The results can help improving personal identification efficiency. Key Points  Fingerprints exposed to various environmental factors are recommended to be evaluated.Visual quality of latent prints decreases with the length of exposure to snow conditions.The average number of minutiae decreases significantly after the influence of snow conditions.Snowfall has a less negative influence on the average number of minutiae than forcible immersion.Latent fingerprints exposed to snowfall have better identification potential.

This contribution aims to analyse an Italian femicide case that progressed through three levels of trial up to the Supreme Court of Cassation and required an expert opinion. This analysis will address specific forensic psychiatry issues inherent to this field, i.e., the interaction between addiction, jealousy, and mental disorder in a femicide case, which necessitates a comprehensive understanding of both criminology and legal medicine. On one hand, the nosographic setup of the so-called dual diagnosis (in the case examined, there was alcohol addiction and a borderline personality disorder), together with conditions inherent to a personality disorder (in this specific case, at least a borderline state or actually marginal manifest disease) that integrated an infirmity with legal relevance. Both conditions were inserted in a relational context of dysfunctional and collusive characters in which the victim's personality caused her, at a victimological level, to become an active partner co-responsible for the criminal act. Key points  Forensic psychiatric analysis in a case of femicide.Nosographic difficulty in making dual diagnosis.Assessment of the perpetrator's mental capacity and of diminished responsibility.Personal predisposition of the victim as an active partner in the crime.

Trauma in victims of abuse often exists in various ways, and the characters usually manifest as non-fatal injuries, repetitive occurrence, and the injured parts are relatively hidden. Forensic experts are optimally positioned to raise suspicion for abuse when comprehensively considering a forensic investigation, reviewing imaging, and other multiple factors of geriatric injury victims. However, few experts received formal or informal training in abuse identification. In this article, we discussed two cases of suspected victims of abuse with rib fractures and attempted to determine the location, timing, and directionality of these injuries to raise the index of suspicion for abuse. We present two cases to characterize the radiographic changes of rib fractures in various stages of healing and radiographic findings in elder abuse events. To improve the accuracy of the imaging diagnosis, we collected a series of computed tomography images of rib fractures and compared all computed tomography images of these two victims with these images. We found that the victims presented with repeated rib fractures and with different stages of healing. We strongly suspect these were abuse cases due to the radiographic findings and clinical recordings demonstrated by these cases. We aim to raise awareness of abuse in radiology and forensic medicine to help these victims and reduce such incidents.

The comparison of footprints to establish positive identification of individuals is an accepted practice. Due to the poor clarity and limited quantity of friction ridge skin detail in the bare footprint at crime scenes, it can prove challenging and problematic to locate the part of the foot that made the print. The aim of the present study is to analyse the types and its distributions of patterns in the ball area of the footprint. The samples comprise 1 460 adults. Results show that loops, whorls, and arches have been found in the ball area of the footprint. In the inner zone, loops are 65.51% of all the patterns, in which vertical loop-down is the most common pattern. In the mid zone, 54.04% of the samples only have vertical loop-down as the single pattern, and 7.71% show multiple patterns, with particularly nine types of multiple patterns found. In the outer zone, patterns are very rare. Only 5.45% of the samples have horizontal loop-outer, and 0.27% of the samples are vertical loop-down. Different patterns in the ball area of the foot show different frequencies of appearance. The shapes of patterns are different in each area of the foot. The examination of the patterns in the bare footprint could be a possibility of locating a certain position of the origin foot.

Dental comparison is recognized by the International Criminal Police Organization as one of three primary forensic identification techniques that can provide conclusive findings. Queensland is a large Australian state with a centralized forensic odontology service located at Queensland Health's Coronial and Public Health Sciences (CPHS) in Brisbane, which sits in the state's South-Eastern corner. Almost half of the Queensland population is located outside of Brisbane, and the distance to regional centres can be very large. Transporting forensic dental personnel and their equipment to these regional centres to undertake identification and examination procedures can be both expensive and time-consuming, depriving CPHS of service for the period of absence. The acquisition of post-mortem computed tomography (PMCT) data locally in regional centres with remote access electronically from CPHS in Brisbane has the potential to alleviate these issues in many cases. Forensic radiographers at CPHS work with forensic odontologists to produce multi-planar reformat images from PMCT data, which simulate common dental radiographs such as orthopantomogram, bitewing, and periapical views. Additional images, such as three-dimensional (3D) reconstructions of the teeth and jaws, can also be produced and viewed from various angles. These multi-planar reformat and 3D images can be compared with antemortem (AM) radiographic images and dental records of a missing person sourced from public or private dental surgeries, public hospitals, or private radiology practices. Comparisons can be made not only with AM traditional dental radiographs but also with images and reconstructions produced from AM dental cone-beam computed tomography or medical computed tomography data. The authors term this remote dental identification "e-dentification". While e-dentification offers numerous advantages, there are several limitations to its use, including access to the necessary equipment, the consistent acquisition of high-resolution PMCT data, and artefacts, including those due to metal restorations, that may be present in computed tomography images. We present four cases to illustrate and discuss e-dentification.