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Impalement injuries represent a rare but forensically relevant form of penetrating trauma that combines characteristics of both blunt and sharp force injury. The mechanisms and reconstruction of such injuries are often complex, particularly in the context of high-energy occupational accidents. Two fatal occupational cases with unusual impalement-like mechanisms are presented. In the first case, a construction worker was struck by a falling metal scaffold tube, resulting in a vertical cranial impalement with destruction of the occipital region and posterior skull base. In the second case, a worker in a high-voltage tunnel sustained fatal injuries caused by a recoiling steel cable, leading to complete transection of the trachea and near-complete rupture of the aorta. Postmortem computed tomography (PMCT) in both cases enabled detailed three-dimensional reconstruction of the injury mechanisms and confirmed the high-energy trajectories of impact. These findings illustrate that impalement injuries, from a forensic perspective, should not be restricted to classical transfixion events. Complex high-energy mechanisms involving secondarily accelerated objects-such as falling rods or recoiling cables-can produce functionally equivalent injury patterns. Their forensic assessment requires interdisciplinary analysis integrating radiological, biomechanical, and technical expertise.

Recent studies focus on the different ways in which DNA can be transferred from and individual to another or to a surface. This work investigates how mixed DNA profiles can be generated on items commonly collected at the crime scene, specifically on cigarette butts. The aim is to determine how biological material exchanged during intimate contact (kissing or sharing a cigarette) can be secondarily transferred onto cigarettes, and how long non-self DNA persists and remains recoverable under different conditions and time intervals. The preliminary experimental study involved one investigative couple: each volunteer smoked a cigarette at fixed intervals after kissing (from 0 to 120 min) and both partners smoked a shared cigarette. DNA was extracted from cigarette butts immediately and after 30 days using the QIAamp DNA Investigator Kit on the QIAcube Connect. Quantification was performed with PowerQuant® System Kit and genetic profiles were obtained using PowerPlex® Fusion and Y23 Kits. Results showed non-self DNA alleles up to 2 h after kissing, even in non-immediate extractions, partial Y-STRs profiles in female butts after 1 h: individual variability and degradation made interpretations harder. Based on preliminary findings, the study will be expanded including more partner pairs, more smoking devices and longer processing timeframes. Our findings suggest the possibility of reconstructing transfer scenarios leading to mixed DNA traces on cigarette butts and of assessing a time window within which non-self DNA can be secondarily transferred to the cigarette, highlighting the impact of processing times and smoking device on DNA results.

Introduction: Suicide is a major global cause of premature mortality and a critical public health concern. Chronic alcohol misuse and illicit drug use are well-established risk factors, but conventional post-mortem toxicology frequently fails to detect long-term substance exposure. Hair analysis represents a valuable forensic tool, enabling the reconstruction of pre-mortem behavioral patterns and offering insight into chronic substance use and its association with suicidal behavior.

Materials and methods: This retrospective study examined 74 suicide cases (59 males, 15 females) from 2023 to 2024. Hair samples were analyzed for ethyl glucuronide to assess chronic alcohol consumption and screened for psychoactive substances. Demographic data, previous suicide attempts, and methods of suicide were also considered.

Results: Chronic excessive alcohol use was identified in 75.7% of cases, with higher prevalence in females (93.3%) and individuals aged ≥ 65 years (88.9%). Illicit drugs were detected in 25.7% of cases, mainly cocaine (23.0%) and cannabis (17.6%). Polydrug use was found in 66.2% of subjects. Psychoactive drugs were frequently present: benzodiazepines in 63.5%, antidepressants in 36.5%, and antipsychotics in 10.8%. A prior suicide attempt was reported in 23.0% of individuals, with the highest rate among adolescents and young adults (29.4%).

Discussion and conclusion: These findings highlight age- and sex-specific toxicological patterns and support the forensic relevance of hair analysis in detecting chronic substance use. Integrating toxicological, clinical, and demographic data enhances post-mortem risk profiling and informs suicide prevention strategies targeting high-risk, underserved populations.

In recent years, Forensic DNA Phenotyping (FDP) has emerged as an innovative "DNA intelligence approach" aimed at predicting externally visible individual characteristics from biological traces collected at crime scenes or from biological samples of unidentified corpses or skeletal remains. This study aims to analyse the allele frequency distribution of genetic markers involved in the prediction of eye and hair colour in an Italian population sample, to enhance the existing European dataset. A large cohort of Italian individuals with at least three generations of ancestry was recruited, ensuring representation of phenotypic variability. The 24 SNP markers included in the HIrisPlex panel were analysed using SNaPshot sequencing technique, and the genotypic data were uploaded to the FDP web tool validated for forensic use by the international VISAGE Consortium's. This tool provides prediction probabilities for three eye colour categories (blue, brown, and intermediate) and four hair colour categories (black, blonde, brown, and red). The results confirmed a high predictive accuracy for the Italian population as well; however, the complex genetic structure of intermediate phenotypic traits highlights the need for novel prediction models that include genetic markers associated with complex phenotypes. The strong north-south European gradient in eye colour, along with the hypothesis that variation in eye colour is associated with skin pigmentation and UV environmental adaptation, underscores the importance for further research. These should focus on novel genetic markers to refine the European dataset, in which the Italian population may be included to enhance the accuracy of predictive models.

Accurate estimation of shooting distance is one of the main aspects in forensic gunshot case reconstruction. Reliable methods to estimate shooting distance are thus important for forensic practitioners. In this pilot study we test how computed tomography (CT) based evaluation of bullet cavitation could potentially be utilized to differentiate shooting distance. To conduct our study, we utilized ballistic gelatine blocks as a soft tissue simulant. Test shooting was performed from two distances, 20 and 100 m. Four expanding monolithic bullets were used all in 0.30 caliber (Barnes TTSX, Sako Blade, Norma Ecostrike, Lapua Naturalis). The gelatine blocks were CT-scanned after the experiment. The scans were processed and segmented using an open-source 3D Slicer software to provide a 3D reconstruction of the cavitation and obtain numerical cavitation parameters (total volume and surface area of cavitation; maximum crack diameter; location of maximum cavitation). Our results indicated that all four bullets had distinct terminal ballistic performance. This could be detected from the bullet parameters such as maximum diameter and also from the pattern of cavitation. Shooting distance had a consistent, measurable association with bullet diameter and surface area of the gelatine cavity in all four bullets. Our preliminary pilot study underscores the potential of CT in the comprehensive analysis of gelatine cavitation in terminal ballistics. Our results suggest that it would be essential to know exact bullet type when shooting distance is estimated from terminal ballistic findings.

Falls are major causes of trauma in older people, often resulting in cervical spine/cord injury, and may even be fatal. We aimed to identify factors associated with cervical spine/cord injury and severe injury caused by falls to aid forensic evaluation. We retrospectively analyzed data for 83 individuals who fell between 2011 and 2023 at Shiga University of Medical Science. The characteristics of the victim, cause of death, presence of cervical spine/cord injury, injury severity, part of the body making contact with the impact surface, properties of the impact surface, and fall height were evaluated. Injury severity was assessed using the Abbreviated Injury Severity score and Injury Severity Score (ISS). Severe injury with ISS ≥ 16 occurred in 39.8% of victims and cervical spine/cord injury in 21.7%. Logistic regression analyses revealed that body mass (odds ratio [OR] 1.063, 95% confidence interval [CI] 1.003-1.126) and the part of the body making contact with the impact surface (chest/abdomen vs. head/face, OR 0.074, CI 0.007-0.723) significantly influenced the incidence of cervical spine/cord injury, and fall height >3 m was significantly associated with severe injury (OR 11.473, CI 2.163-60.868). These findings demonstrate that the severity of injury depends on the fall height, whereas cervical spine/cord injury is influenced by body mass and the part of the body making contact with the impact surface. Therefore, the collection of scene information, including the fall height, and body mass and posture are critical for postmortem examinations. Autopsy should be considered when cervical spine/cord injury is suspected.