Bloodstain pattern analysis in a case of fatal varicose vein rupture

Rupture of a varicose vein is a rare cause of sudden death. It occurs when the failure of venous valves causes an increase in venous pressure great enough to provoke rupture of the blood vessel. When it does happen, the victim is often found surrounded by a pool of blood, and the examination of the scene can mislead the forensic team to think of violent death. Until now, the bloodstain patterns in these fatal cases have not been described. An examination of the bloodstain pattern in a case of fatal varicose vein rupture in an 84-year-old man is here reported.     

Virtual autopsy and forensic identification-practical application: a report of one case

The body of an unidentified elderly woman was found trapped in a floodgate. Prior to autopsy, full-body multislice computed tomography (MSCT) was performed for study of bone lesions and cause of death. Age was estimated by analysis of the sternal end of the fourth rib and of the pubic symphyseal medial articular surfaces. The results were then compared with the autopsy findings. MSCT was superior to autopsy in diagnosis of traumatic bone lesions and also revealed dental anomalies and signs of drowning. Age estimation gave a similar result for both methods. This case report illustrates the potential value of MSCT for medico-legal investigations of death: diagnosis of injuries, possibility of determining the cause of death, and anthropological study in order to estimate age or to visualize features likely to enable identification of a corpse.     

Fatal MDMA-intoxication with postmortem diagnosis of hyperthermia

Hyperthermia is one of the main symptoms of the toxic MDMA effect. In a fatal intoxication, the premortal increase in body temperature may lead to a false assessment of the time of death. The problems of drug-induced hyperthermia faced by forensic pathologists and criminal investigators are discussed on the basis of a death from the autopsy material of the Berlin Institute of Legal Medicine (CCM).     

An extreme case of undoing and posing in a case of murder-suicide. A forensic pathological approach to crime scene investigation

A 7-year-old boy was killed by his father by manual strangulation during a murder-suicide. After the killing of the son, the father showed typical "undoing" behaviour: He changed the boy's clothes and laid him down on the bed. Then he placed candles around his head, put pictures of the parents' wedding around him and a crucifix and a picture of the family into his hands. He broke off a rose in a vase next to the bed, lit the candles and took photographs of his dead son. Later he called his wife, threatened to kill the son and finally called the police to confess the murder and to announce his forthcoming suicide.     

Methyl 3-[3',4'-(methylenedioxy)phenyl]-2-methyl glycidate: an ecstasy precursor seized in Sydney, Australia

Five 44 gallon drums labeled as glycidyl methacrylate were seized by the Australian Customs Service and the Australian Federal Police at Port Botany, Sydney, Australia, in December 2004. Each drum contained a white, semisolid substance that was initially suspected to be 3,4-methylenedioxymethylamphetamine (MDMA). Gas chromatography-mass spectroscopy (GC/MS) analysis demonstrated that the material was neither glycidyl methacrylate nor MDMA. Because intelligence sources employed by federal agents indicated that this material was in some way connected to MDMA production, suspicion fell on the various MDMA precursor chemicals. Using a number of techniques including proton nuclear magnetic resonance spectroscopy ((1)H NMR), carbon nuclear magnetic resonance spectroscopy ((13)C NMR), GC/MS, infrared spectroscopy, and total synthesis, the unknown substance was eventually identified as methyl 3-[3',4'(methylenedioxy)phenyl]-2-methyl glycidate. The substance was also subjected to a published hydrolysis and decarboxylation procedure and gave a high yield of the MDMA precursor chemical, 3,4-methylenedioxyphenyl-2-propanone, thereby establishing this material as a "precursor to a precursor."     

A study to narrow down the time when a hyoid bone fracture was sustained

An unstable hyoid bone that can be loosely moved during autopsy is initial reason to suspect trauma to the neck. The question to be answered is whether the increased mobility is due to incomplete ossification of the hyoid, a postmortem injury (damage), or an ante-mortem injury, possibly related to the cause of death. This is the first study to systematically assess whether stereomicroscopic examinations and flat-panel CT-scans of isolated, unstable hyoid bones can add information to the macroscopic examination by helping to determine when the instability arose. Sixteen isolated hyoid bones (8 female, 8 male; 4-87 years-old) were examined after being macerated. Four of the hyoid bones were already classified as unstable during autopsy. Of the other 12, 7 were fractured immediately after autopsy before being macerated, and 5 were fractured after being macerated. There were, in total, six different diagnostic constellations. Stereo-microscopic examination did not yield additional information compared with the macroscopic examination. Flat-panel CT allowed distinction between an incomplete ossification of the hyoid and a fracture, but did not help in determining whether the fracture had been sustained peri- or postmortem.     

PowerPlex(R) 16 HS系统直接扩增法检测常见检材的DNA

目的研究PowerPlex 16 HS系统直接扩增法对血样、口腔拭子和烟蒂3种常见检材的有效性。方法采用PowerPlex 16 HS系统对11份新鲜血样、10份口腔拭子和10份烟蒂样本进行直接扩增检测,对所得数据进行统计分析。结果新鲜血样和口腔拭子的完整遗传图谱检测成功率为100%,烟蒂样本的完整遗传图谱检测成功率为90%。结论 PowerPlex 16 HS系统直接扩增法是一种适用于血样、口腔拭子和烟蒂3种常见检材的有效方法。     

Is the appearance of macrophages in pulmonary tissue related to time of asphyxia?

In order to connect the appearance of macrophages and giant cells in pulmonary tissue with the time of asphyxia the authors analyzed 50 asphyxiated human lungs paying their attention on the number of alveolar and interstitial macrophages and giant cells. They compared histological specimens of 25 asphixiated humans lungs following a slow asphyxia (30 min or more) with 25 histological specimens of asphyxiated human lungs following a rapid asphyxia (10-15 min). Alveolar and interstitial macrophages and giant cells per section, were considered and numbered. Controls were done on histological examination of traumatized lungs. In the pulmonary alveoli following on acute asphyxia there were 27.7+/-4.4 macrophages per section. Subjects dead after a slow asphyxiation showed 68.2+/-7.1 alveolar macrophages per section (p<0.001). Interstitial macrophages were also frequently present. No differences are detectable in the number of polynuclear giant cells between rapidly and slowly asphyxiated human lungs. The number of alveolar and interstitial macrophages per section can be considered as a further histological evidence of a slow asphyxia and can differentiate a slow asphyxia from an acute one.     

Image matching algorithms for breech face marks and firing pins in a database of spent cartridge cases of firearms

On the market several systems exist for collecting spent ammunition data for forensic investigation. These databases store images of cartridge cases and the marks on them. Image matching is used to create hit lists that show which marks on a cartridge case are most similar to another cartridge case. The research in this paper is focused on the different methods of feature selection and pattern recognition that can be used for optimizing the results of image matching.The images are acquired by side light images for the breech face marks and by ring light for the firing pin impression. For these images a standard way of digitizing the images used. For the side light images and ring light images this means that the user has to position the cartridge case in the same position according to a protocol. The positioning is important for the sidelight, since the image that is obtained of a striation mark depends heavily on the angle of incidence of the light. In practice, it appears that the user positions the cartridge case with +/-10 degrees accuracy.We tested our algorithms using 49 cartridge cases of 19 different firearms, where the examiner determined that they were shot with the same firearm. For testing, these images were mixed with a database consisting of approximately 4900 images that were available from the Drugfire database of different calibers.In cases where the registration and the light conditions among those matching pairs was good, a simple computation of the standard deviation of the subtracted gray levels, delivered the best-matched images. For images that were rotated and shifted, we have implemented a "brute force" way of registration. The images are translated and rotated until the minimum of the standard deviation of the difference is found. This method did not result in all relevant matches in the top position. This is caused by the effect that shadows and highlights are compared in intensity. Since the angle of incidence of the light will give a different intensity profile, this method is not optimal.For this reason a preprocessing of the images was required. It appeared that the third scale of the "à trous" wavelet transform gives the best results in combination with brute force. Matching the contents of the images is less sensitive to the variation of the lighting.The problem with the brute force method is however that the time for calculation for 49 cartridge cases to compare between them, takes over 1 month of computing time on a Pentium II-computer with 333MHz. For this reason a faster approach is implemented: correlation in log polar coordinates. This gave similar results as the brute force calculation, however it was computed in 24h for a complete database with 4900 images.A fast pre-selection method based on signatures is carried out that is based on the Kanade Lucas Tomasi (KLT) equation. The positions of the points computed with this method are compared. In this way, 11 of the 49 images were in the top position in combination with the third scale of the à trous equation. It depends however on the light conditions and the prominence of the marks if correct matches are found in the top ranked position. All images were retrieved in the top 5% of the database. This method takes only a few minutes for the complete database if, and can be optimized for comparison in seconds if the location of points are stored in files.For further improvement, it is useful to have the refinement in which the user selects the areas that are relevant on the cartridge case for their marks. This is necessary if this cartridge case is damaged and other marks that are not from the firearm appear on it.     

Discriminating red spray paints by optical microscopy, Fourier transform infrared spectroscopy and X-ray fluorescence

Red spray paints from different European suppliers were characterised to determine the discriminating power of a sequence of analysing techniques. A total of 51 red spray paints were analysed with the help of three techniques: (1) optical microscopy, (2) Fourier transform infrared spectrometry and (3) X-ray fluorescence. Infrared spectra were classified according to binder type, filler and pigment composition and a searchable spectral library was created. Due to the difference in the elemental composition of spray paints, a further discrimination was possible. The microscopic analysis was not taken into consideration for classification purposes. The structure of the substrate under a paint coating strongly affects the surface characteristics of this spray paint. Together with the spectral library, a database of information of spray paints was build.