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Cerebral hemorrhages are rare complications that occur after the consumption of amphetamine; the mortality rate is estimated at 50 %. It is assumed that cerebral hemorrhages are caused by amphetamine-induced hypertensive crises coinciding with pre-existing vascular alterations (congenital vascular malformations, vasculitis). In the present case report, a 40-year-old man, who is said to have regularly consumed hashish, heroin and speed, died of a massive cerebral hemorrhage located in the region of the basal ganglia shortly after the intravenous administration of amphetamine and heroin. In the course of the post-mortem investigation, neither vascular malformations nor vasculitis could be detected in the brain. Even if the evidence for the existence of such alterations was missing, this does not exclude their presence for certain. Other potential amphetamine-induced vascular alterations are discussed.  相似文献   
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A 77-year-old man was found in his flat with a shot to the right temple. In spite of hospital treatment he died from the head injury the next day. The weapon at the scene used for committing the suicide was a pistol, make Kaba Special (calibre 6.35 mm). At autopsy, the right temporal region showed a surgically treated, originally stellate gunshot entrance wound with a powder cavity. Close to this penetrating gunshot wound there were 3 parallel graze shot injuries of the scalp. The autopsy findings were consistent with the assumption that all the shots had been fired by the victim himself with suicidal intent. The injury pattern is presented and discussed in relation to the results of the technical investigation of the weapon and the findings at the scene.  相似文献   
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A sensitive, specific and simple color test for the improvised explosive urea nitrate is described. It is based on the formation of a red pigment upon the reaction between urea nitrate and p-dimethylaminocinnamaldehyde (p-DMAC) under neutral conditions. Urea itself, which is the starting material for urea nitrate, does not react with p-DMAC under the same conditions. Other potential sources of false positive response e.g., common fertilizers, medications containing the urea moiety and various amines, do not produce the red pigment with p-DMAC. Exhibits collected from 10 terrorist cases have been tested with p-DMAC. The results were in full agreement with those obtained by instrumental techniques including GC/MS, XRD and IR.  相似文献   
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Previous research conducted into the use of the human ear in the field of forensic identification has focused upon the use of grids and manual methods to measure and catalogue the different anatomical features of the ear. To date, few have considered the importance of the presence of ear piercings and their possible role in human identification. This study aims to highlight the common distribution of piercings of both ears in both genders and to explore the effect of piercings on earprints. The presence of a piercing may, in part, help to explain why partial and not whole earprints are sometimes recovered from a scene of crime (suggesting that the offender's ears may be pierced). The presence of piercings through the tragus and the superior part of the helix are shown to be infrequent and thus may be used to assist the identification of a body, due to its relative rarity with respect to piercings found in other areas of the ear.  相似文献   
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In a "mafia" crime case, a magistrate asked us whether it is possible to destroy a cadaver by immersing it in acids, and would it be possible to identify any residues. The aim of this study was to observe the behavior of teeth exposed to four kinds of acid solutions. The teeth were placed in plastic containers with 25 mL of acid and observed. The experiences showed that teeth are completely dissolved after 14 h of immersion in 37% solution of hydrochloric acid, while at 90h in 96% sulfuric acid, the destruction of the samples is still incomplete. In nitric acid the teeth undergo a complete dissolution in 12 h, and in 17 h in aqua regia (chloroazotic acid-hydrochloric/nitric acid 1:3). It was possible to recognize the characteristic morphological features of dental tissues and structures up until the advanced stages of degradation.  相似文献   
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Forensic analysis of glass samples was performed in different laboratories within the NITE-CRIME (Natural Isotopes and Trace Elements in Criminalistics and Environmental Forensics) European Network, using a variety of Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) systems. The main objective of the interlaboratory tests was to cross-validate the different combinations of laser ablation systems with different ICP-MS instruments. A first study using widely available samples, such as the NIST SRM 610 and NIST SRM 612 reference glasses, led to deviations in the determined concentrations for trace elements amongst the laboratories up to 60%. Extensive discussion among the laboratories and the production of new glass reference standards (FGS 1 and FGS 2) established an improved analytical protocol, which was tested on a well-characterized float glass sample (FG 10-1 from the BKA Wiesbaden collection). Subsequently, interlaboratory tests produced improved results for nearly all elements with a deviation of < 10%, demonstrating that LA-ICP-MS can deliver absolute quantitative measurements on major, minor and trace elements in float glass samples for forensic and other purposes.  相似文献   
210.
Validation of a recently proposed differentiation method for single poly (ethylene terephthalate) (PET) fibers, based on integration of IR absorption bands, is presented. IR microscopy in the transmission mode, differential scanning calorimetry and optical microscopy were employed. The reliability of the technique has been extended to the cases in which the fibers being compared have experienced long exposure to the elements, as may happen if these items are recovered from open-air crime scenes. The effect of immersion in water and irradiation by the sun for a three-month period have been considered. The fibers remained morphologically and structurally unaltered. The significance of comparisons between fibers kept in different environments is thus enhanced, because the detrimental effect of the elements can be ruled out. This further validation of the proposed technique contributes to render the data presented by the forensic scientist less vulnerable to context effect and bias.  相似文献   
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