International Journal of Legal Medicine最新文献

Due to the complexity of the decomposition process and all the variables affecting it, there are many factors that have not been thoroughly examined. The impact of different soil types on decomposition of buried remains has received relatively little attention. This study sought to investigate the impact of three soil types on decomposition. Fourteen piglet carcasses were used to assess and compare the decomposition patterns and rates that take place in dolomite and quartzite (two soil types common in the city of Johannesburg, South Africa), as well as in tailings from gold mines (another common feature in southern Johannesburg). Each piglet was buried in a container filled with one of these soil types (four for Dolomite, five for quartzite and mine tailings) and was periodically partially exhumed to record Total Body Score progression as thermal energy (measured in Accumulated Degree Days) accumulated. Soil samples were also taken to record the soil's water content and pH level. The decomposition of the dolomite and mine tailing-interred piglets was found to differ significantly, with the latter progressing more rapidly. Dolomite was also consistently the soil type with the lowest water content and the least pH fluctuation, while quartzite had the highest water content and the most significant changes in pH over the course of the experiment. While this study has experimental limitations, it provides novel results that will help forensic practitioners understand subterranean decomposition in South Africa, and possibly other countries with similar climates and soil types.

Background and aim: Skeletal remains are sometimes discovered with the mandible missing from the skull due to external factors such as environmental conditions or scavenger activity. The absence of the mandible reduces the accuracy of forensic identification methods, including facial reconstruction. Although we previously established a two-dimensional method for estimating mandibular measurements (e.g., bicondylar breadth) commonly used in forensic practice, no method has yet been developed for estimating the entire three-dimensional mandibular shape. Therefore, the aim of this study was to establish a method for three-dimensional estimation of a missing mandible from the remaining cranium using an image analysis technique based on homologous modeling theory.

Materials and methods: Postmortem CT images of 200 Japanese subjects were used to create homologous models of the cranium (8,739 vertices) and mandible (4,255 vertices), ensuring that all samples contained the same number of vertices. Principal component regression analysis was then performed using the three-dimensional point cloud data obtained from each homologous model to construct a three-dimensional estimation model. Estimation accuracy was subsequently validated using separate samples.

Results: The mean error between all corresponding vertices of the estimated mandible and the actual mandible (ground truth) was 2.324 ± 0.659 mm. In addition, visualization analysis using multidimensional scaling confirmed that most of the estimated shapes were distributed close to the ground truth.

Conclusion: The estimation method developed in this study demonstrated a satisfactory degree of accuracy, suggesting its potential usefulness for three-dimensional estimation of missing mandibular morphology.

Postmortem interval (PMI) estimation is mandatory in any forensic investigation. Although it remains a very challenging task, particularly in skeletonized human remains. Luminol chemiluminescence has been explored as a tool for PMI estimation, however, its application requires further experimental validation to ensure accuracy and reproducibility. The present research aims to increase the objectivity of PMI estimation by quantifying the light emission from the luminol chemiluminescence reaction. For this purpose, a sample of clavicles collected from 24 adult individuals of both sexes, with known PMI ranging from 7 to approximately 500 years, was selected. After being reduced to powder, the samples were analyzed on a CCD camera with an image intensifier, and the reaction Ipeak was measured. The results obtained revealed a clear inverse relationship between PMI and Ipeak values. A segmented regression analysis identified a statistically supported threshold at approximately 30 years postmortem, distinguishing a variable early postmortem phase from a long-term phase characterized by consistently low and minimally variable chemiluminescence intensities. This pilot study supports the validity of quantifying the luminol chemiluminescence reaction as a feasible and informative presumptive screening tool for PMI estimation, with potential applicability in distinguishing remains of forensic interest from those of archaeological relevance.

As the largest human organ, the skin frequently interacts with the environment and retains abundant microbial information, making it a crucial source of forensic biological evidence. However, the temporal dynamics of microbial communities between in situ and in vitro samples, as well as the traceability of in vitro samples back to their donors based on corresponding in situ samples, remain unverified through longitudinal sampling and dynamic tracking. A total of 15 young adult volunteers participated in the study, during which skin microbiome samples were collected from their palms and cheeks. A short-term exposure experiment was designed, with a duration of between 0 and 72 hours. Fresh samples were collected at corresponding timepoints, in a synchronised manner. In this study, we utilised a combination of 16S rRNA gene (V3-V4 regions) sequencing and machine learning algorithms to analyse the environmental exposure effects on microbial community structure and their forensic applicability. The results indicated that the relative abundance of dominant genera remained largely stable, regardless of exposure status, with no significant temporal variations observed in the short term. Although individual lifestyles exerted an influence on microbiome composition, they did not affect significant alterations to the overall community architecture. The random forest model attained an accuracy of 91.33% in skin site identification, while the individual differentiation accuracy attained 97.33% when integrating palm and cheek data. These results indicate that the skin microbiome exhibits considerable structural stability under both in situ and in vitro conditions during short-term exposure and maintains high host specificity and site-specific characteristics.

Objectives: Individual dental age estimation systems provide essential information in law and forensic sciences for the living and deceased. Considering the multi-ethnic population of Australia, it is important to compare the performance of the internationally recognized London Atlas against the Australian-developed Blenkin Taylor age estimation system.

Methods: 218 anonymized digital panoramic radiographs of children aged 5-18 years old were reviewed and 200 met inclusion criteria. The qualified radiographs were subjected to both the London Atlas and Blenkin Taylor age estimation systems, and this was compared to the children's real ages.

Results: The Blenkin Taylor method produced a statistically significant mean underestimation of 0.34 ± 1.44 years, while the London Atlas also produced a statistically significant mean underestimation of 0.96 ± 1.64 years.

Conclusion: Both age estimation systems produced a significantly smaller difference between the estimated and chronological age for females compared to males. Both the London Atlas and Blenkin Taylor are appropriate to apply in an Australian paediatric population for the purposes of forensic age estimation.

This study developed and evaluated data mining models for age estimation and legal age thresholds classification based on elbow MRI in a contemporary Chinese population. A total of 867 patients (614 males and 253 females) aged 30 years or younger were retrospectively included, and T1-weighted coronal elbow MRI images were assessed by experts using five age-related indicators. Multiple data mining models were constructed, with mean absolute error (MAE) as the primary performance metric. Both intra- and inter-observer agreements demonstrated good reliability. In external validation, the optimal model achieved the lowest MAE of 2.9845 years in males and 2.9767 years in females, compared to 2.0471 years and 3.0477 years, respectively, in internal validation. For classification at the 12-, 14-, 16-, and 18-year threshold, the area under the receiver operating characteristic curve (AUC) exceeded 0.90 across all models. Notably, these models also attained the highest specificity (defined as the proportion of individuals truly below the threshold correctly identified) reaching 1.000, 1.000, 0.970, and 0.800 in males, and 1.000, 1.000, 0.857, and 0.750 in females at the respective thresholds. In conclusion, the proposed models show promise in estimating age and classifying legal thresholds, with performance that is generally comparable to that of other MRI-based approaches in certain contexts. These preliminary findings suggest that elbow MRI may serve as a useful tool for age assessment in the Chinese population, though further validation is warranted to confirm its generalizability.

In medico-legal literature, the notion of the "dignity of the corpse" is frequently used as a narrative device, almost romantic in nature, aimed at highlighting the values attributed to it and thereby justifying its defense. The most common explanations tend to focus on its strictly practical effects (in relation to the living), either by pointing to a certain inviolability or by emphasizing some consequences at a symbolic level. Intentionally or not, some of these theories undertake the bold task of explaining the consequences of a phenomenon (the death/dead binomial) while disregarding the study of the material object that sustains this phenomenon, as well as the phenomenon itself. This paper proposes a reflection on the parallels between human dignity (better understood) and the so-called dignity of the dead (practically unknown), advancing an argumentative model (ontological/anthropological) that defends the existence of a 'special dignity of the corpse'. This sui generis dignity demands a sui generis treatment, whose practical applications-both in forensic science and other biological disciplines-can only be determined subsequently, after undergoing moral scrutiny.

Molecular analyses were conducted on skeletal remains discovered in a late medieval burial site beneath the former Convent of San Francesco in Mirandola, Modena, Italy. Part of the burial ground was exposed, revealing infant and adult graves dating to the construction period of the complex (14th-15th centuries AD). Thirty graves were identified which had been buried directly in the ground. They were arranged in several strictly overlapping layers and oriented along an east-west axis in accordance with Christian tradition. The historical context is poorly documented; no archival records are available regarding the causes of death or the reasons for burial at this site. Genetic analyses were conducted to complement the ongoing archaeological and anthropological studies of the site in an attempt to reveal relationships, confirm the number of individuals, explain the burial arrangements, and reconstruct their external appearance and ancestry. Ancient DNA (aDNA) was analysed using the molecular workflow routinely adopted for forensic samples. Teeth and bones were collected. DNA was isolated using a powder-free decalcification and extraction protocol. Autosomal and Y-STR markers were genotyped and Y-haplogroups inferred. The HIrisPlex system was then used to predict eye and hair colour. The results for seventeen individuals are presented herein, alongside an evaluation of the performance of this workflow when applied to severely degraded human remains. The usefulness of the powder-free decalcification protocol was also evaluated, demonstrating its applicability to both ancient and forensic samples of buried skeletal remains recovered under comparable conditions.