Estimating Projectile Perpendicular Impact Velocity on Metal Sheet Targets from the Shape of the Target Hole

Abstract:  The correlation between bullet hole shapes in metal and projectile impact velocity was examined. A series of shots were fired from an M-16A1 assault rifle of 5.56 mm caliber toward a 1-mm thick metal target. All shots were fired at a perpendicular angle to the metal sheets, and the velocity was measured just before the projectile hit the target. Velocities ranged between 400 and 900 m/sec. From the replica of the shooting hole, a perpendicular plane was created, showing the symmetrical properties of the hole. The best mathematical equation describing the shape of the entrance hole was the exponential function in the form:
The empirical equation of the hole defined using the regression method is:
This equation describes the general shape of shooting holes created by velocities ranging from 440 to 750 m/sec. From this equation, one can estimate the bullet velocity when it hits the target.     

Fatal hemorrhage from a periumbilical wound: Stabbing or hemorrhage from a caput medusae?

Varices are the main clinical manifestation of portal hypertension, and their bleeding is the predominant cause of mortality from this condition. Periumbilical varices are known as “caput medusae.” Reports of their bleeding are rare, with only three fatal cases described in the literature. The antemortem diagnosis is relatively simple, while the postmortem diagnosis is more complex. This paper is the first report of fatal hemorrhage from a caput medusae for which the diagnosis was made postmortem, thanks to a complete diagnostic process including scene and circumstances, medical history, and autopsy with detailed histology. The circumstantial analysis showed the presence of a large amount of blood at the scene, blood which originated from a small abdominal wound; an analysis of the subject's clinical data reported that he was affected by portal hypertension. The autopsy revealed some dilated and convoluted veins in the subcutaneous tissue of the umbilical region; a fistula between these veins and the abdominal wound was detected. The histological study confirmed the presence of periumbilical varices, one of them ruptured and connected with the overlying skin. The cause of death was attributed to a massive hemorrhage generated by a periumbilical varix in a patient affected by portal hypertension.     

3D forensic facial approximation: Implementation protocol in a forensic activity

The primary objective of this paper is to report on the successful implementation of forensic facial approximation in a real case in the forensic context. A three‐dimensional (3D) facial approximation protocol of the skull was performed with free software, applying techniques in a virtual environment that have already been consolidated in the literature. The skull was scanned with the photogrammetry technique, the digital replica was imported in the Blender software (Blender Foundation, Amsterdam) and individualized model sketches of the face were traced with the MakeHuman software (MakeHuman Org) according to the anthropological profile of the victim. The face created was imported in Blender, where it was adapted, modeled, and sculpted on the 3D skull and its soft tissue markers, using an American open‐source application of the technique in the digital environment. The face created in a virtual environment was recognized and legal identification procedures were started, resulting in the more agile delivery of the disappeared body to its next of kin. It is therefore concluded that facial approximation may not be a primary method of human identification, but it can be satisfactorily applied in the forensic field as an individual recognition resource. It has great value in narrowing the search, reducing the number of alleged victims, and leading to identification tests, therefore significantly reducing the number of genetic DNA (deoxyribonucleic acid) tests—which are considered costly for the State or Federation—and consequently reducing the waiting time before delivery of the body to its family.     

Primary intimal sarcoma of the pulmonary artery misdiagnosed as pulmonary thromboembolism: A case confirmed at medicolegal autopsy

Misdiagnosed PAS confirmed at medicolegal autopsy Pulmonary artery sarcoma (PAS) is a rare disease and usually indistinguishable from acute or chronic thromboembolic disease of the pulmonary arteries. We present a case of pulmonary artery sarcoma in a 54‐year‐old male, who was clinically misdiagnosed as pulmonary thromboembolism. The patient died of disease; however, the actual diagnosis of PAS was made after a medicolegal autopsy. PAS can be a diagnostic challenge for both clinicians and pathologists. In an autopsy case with a clinical suspicion of pulmonary thromboembolism, if there is an abnormal gross appearance in the pulmonary artery, the forensic pathologist should have a high index of suspicion of PAS, which should be ruled out by a histopathologic examination.     

Intentional overdose of glargine insulin: Determination of the parent compound in postmortem blood by LC-HRMS

Insulin glargine is a long-acting insulin analog that is converted after enzymatic cleavage of the arginine pair of the β-chain into its main metabolite M1 (21^A-Gly-insulin), which is responsible for the hypoglycemic activity. In all the overdose cases described in the literature, only M1 concentrations have been reported, whereas insulin glargine was always absent or below the limit of quantitation. In this study, we present a case of suicide of a young nurse by injection of insulin glargine in which the parent molecule was found at a toxic concentration in blood. The determination and the discrimination of insulin glargine from human insulin and other synthetic analogs in the blood specimen were performed by liquid chromatography coupled to high-resolution mass spectrometry (Waters XEVO G2-XS QToF) and extraction after precipitation in the presence of bovine insulin (internal standard), with a mixture of acetonitrile/methanol +1% formic acid followed by purification on solid phase extraction cartridges C18. Glargine insulin tested highly positive in the blood with a concentration of 1.06 mg/L. Due to the difficulty in obtaining a M1 pure standard, the metabolite could not be dosed. This unique presence of the parent molecule, reported for the first time, can be explained by inter-individual variability in the rate of conversion to metabolite. Intravenous injection versus subcutaneous injection can also explain the presence of insulin glargine. Finally, the dose injected may have been so high that saturation of the proteolytic enzymes responsible for conversion to M1 should have occurred.     

Radiodense bullet wipe around osseous entrance gunshot wounds

“Bullet wipe” is the material deposited by a bullet on any surface with which it comes into contact after it is fired and may contain debris from the gun barrel, including particles of primer and metal fragments from previously fired bullets. X‐ray analysis is a non‐destructive method by which traces of metallic elements can be visually detected. The analysis of osseous defects for radiodense bullet wipe (RBW) assists in determining the presence or absence of perforating gunshot wounds, especially in fragmented, skeletonized remains. The aim of our current study was to determine the frequency of RBW around entrance firearms injuries that perforated bone. We prospectively analyzed entrance gunshot wounds for RBW over a three‐year period using digital X‐ray analysis (n = 59). We retrospectively reviewed the corresponding autopsy reports to determine the frequency of RBW by biologic sex, reported ancestry, age‐at‐death, location of wound, manner of death, range of fire, bullet caliber, and presence of bullet jacket. Data were analyzed by Fisher's exact test or Chi‐square test with significance levels accepted at p < 0.05. RBW was present in 66% (n = 39) of examined cases. Decedent characteristics did not significantly alter RBW distribution, including biologic sex (p = 0.75), reported ancestry (p = 0.49), and age‐at‐death (p = 0.43). Additionally, the location of the osseous entrance gunshot wound, manner of death, range of fire, and cartridge caliber did not affect RBW detection. All cases involving non‐jacketed rounds (n = 5) showed RBW (p = 0.30). To our knowledge, this study is the first to report the frequency of RBW detection from osseous entrance gunshot wounds.     

The Longitudinal Effects of Chronic Mediated Exposure to Political Violence on Ideological Beliefs About Political Conflicts Among Youths

This study examines the effects of chronic (i.e., repeated and cumulative) mediated exposure to political violence on ideological beliefs regarding political conflict. It centers on these effects on young viewers, from preadolescents to adolescents. Ideological beliefs refers here to support of war, perception of threat to one’s nation, and normative beliefs concerning aggression toward the out-group. A longitudinal study was conducted on a sample of Israeli and Palestinian youths who experience the Israeli-Palestinian conflict firsthand (N = 1,207). Two alternative hypotheses were tested: that chronic exposure via the media increases support for war and aggression and elevates feeling of threat, or that chronic exposure via the media strengthens preexisting beliefs. Results demonstrated that higher levels of exposure were longitudinally related to stronger support for war. Regarding normative beliefs about aggression and threat to one’s nation, mediated exposure reinforced initial beliefs, rendering the youths more extreme in their attitudes. These results mostly support the conceptualization of the relation between media violence and behaviors as “reciprocally determined” or “reinforcing spirals.” The results are also discussed in light of the differences found between the effect of exposure to political violence firsthand and exposure via the media.