Color separation in forensic image processing

In forensic image processing, it is often important to be able to separate a feature from an interfering background or foreground, or to demonstrate colors within an image to be different from each other. In this study, a color deconvolution algorithm that could accomplish this task is described, and it is applied to color separation problems in document and fingerprint examination. Subtle color differences (sometimes invisible to the naked eye) are found to be sufficient, which is demonstrated successfully for several cases where color differences were shown to exist, or where colors were removed from the foreground or background. The software is available for free in the form of an Adobe Photoshop-compatible plug-in.     

Reduction of postmortem angiography-induced tissue edema by using polyethylene glycol as a contrast agent dissolver

Postmortem investigation is increasingly supported by computed tomography (CT) and magnetic resonance imaging, in which postmortem minimal invasive angiography has become important. The newly introduced approach using an aqueous contrast agent solution provided excellent vessel visualization but was suspected to possibly cause tissue edema artifacts in histological investigations. The aim of this study was to investigate on a porcine heart model whether it is possible to influence the contrast agent distribution within the soft tissue by changing its viscosity by dissolving the contrast agent in polyethylene glycol (PEG) as a matrix medium. High-resolution CT scans after injection showed that viscosities above c. 15 mPa s (65% PEG) prevented a contrast agent distribution within the capillary bed of the left ventricular myocardium. Thereby, the precondition of edema artifacts could be reduced. Its minimal invasive application on human corpses needs to be further adapted as the flow resistance is expected to differ between different tissues.     

Virtopsy hemorrhage of the posterior cricoarytenoid muscle by blunt force to the neck in postmortem multislice computed tomography and magnetic resonance imaging

In forensic autopsies, one of the most important and common signs of violence to the neck is hemorrhages of the soft tissues. The Institute of Forensic Medicine in Bern evaluates the usefulness of postmortem multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) of forensic cases prior to autopsy. The aim of this study was to prove the sensitivity of postmortem MSCT and MRI in the detection of hemorrhages of the neck muscles. A full body scan prior to and a detailed scan of the explanted larynx after autopsy were performed. MSCT detected multiple fractures of the larynx. Detailed MRI was able to demonstrate the hemorrhage of the left posterior cricoarytenoid muscle. The minor hemorrhage of the right posterior cricoarytenoid muscle could not be detected with certainty. Although more experience is required, we conclude that combined MRI and MSCT examination is a useful tool for documentation and examination of neck muscle hemorrhages in forensic cases.     

Negotiated Third Party Access—An Industrial Organisation Perspective

In the course of the liberalization of European energy markets, the German government opted—diverging from all other European countries—for Negotiated Third-Party Access. In this article we analyze if, theoretically, this institutional regime can be superior to regulation. We review empirically whether certain aspects of the actual implementation, in particular publication of the network access charges for each network supplier, facilitated or inhibited competition. In the first place we reconsider previous research, showing that NTPA can—under certain conditions—be economically effective. Our empirical analysis shows that the duty of publishing access charges supported market transparency and imposed a regulatory threat, particularly to suppliers with significantly above-average charges. On the other hand observable price adjustments over time serve as an indicator of tacit collusion. Although the expensive suppliers cut their prices, the cheaper ones raised theirs.We thank Maik Heinemann, Joachim Wagner and two anonymous referees for helpful comments and the Lower Saxonian Ministry of Science and Culture for financial support.JEL Classification: D42, L43, L94     

Assessment of intra- and intercostal variation in rib histomorphometry: its impact on evidentiary examination

Rib histological age estimation requires the evaluation of the middle third of the sixth rib. Human ribs have thin cortices and, when recovered, are often fragmented or absent, making it difficult to identify a specific midthoracic rib. This research explores the amount of microstructure variation in the middle third of the midthoracic ribs and determines whether the sixth rib age prediction equation can be applied to non-sixth ribs with similar accuracy. The amount of variability must be evaluated in order to meet the criterion for evidentiary examination. The sample consists of 120 cortical bone cross-sections from the middle third of ribs 3-8 removed from 20 cadavers. For each rib, osteon population densities (OPDs) and associated age estimates were calculated. The results demonstrate that non-sixth ribs can provide similar OPD values compared with those of the sixth ribs; however, individual variation proved to be significantly associated with bias, suggesting that individual factors influence the magnitude and direction of bias in non-sixth rib OPD values. This demonstrates the importance of evaluating multiple cross-sections (both intra- and inter-rib) to estimate age due to the normal remodeling variation within individuals.     

Acute pancreatitis presenting as sudden, unexpected death: an autopsy-based study of 27 cases

Acute pancreatitis represents a spectrum of disease, ranging from a mild, transitory illness to a severe, rapidly progressive hemorrhagic form, with massive necrosis and mortality rates of up to 24%. The reported incidence of acute pancreatitis diagnosed first at clinicopathologic autopsy ranges between 30% and 42%. To better describe outpatient fatalities due to acute pancreatitis that present as sudden, unexpected death, we retrospectively reviewed the autopsy files at the Institute of Legal Medicine, University of Hamburg, Germany, from 2000-2004. Individual cases were analyzed for sex, age, race, circumstances of death, social background of the deceased and previous medical history, seasonal occurrence of the disease, blood alcohol concentration at the time of death, body mass index, autopsy findings, histopathology, and etiology of acute pancreatitis. Among the 6178 autopsies carried out during the 5-year period evaluated, there were 27 cases of acute pancreatitis that presented as sudden, unexpected death. In all cases, the diagnosis was first made at autopsy. The male:female ratio was 1.7:1 and the mean age was 52 years (range, 30-91 years). Etiologies of acute pancreatitis included alcohol (n=19), gall stones (n=2), other identified etiologic factors (n=3), and idiopathic (n=3). Complications of acute pancreatitis included lung edema and/or acute respiratory distress syndrome, peritonitis, disseminated intravascular coagulation, and sepsis. At least 20 subjects (74%) had lived isolated, with no social contacts. Contrary to the clinical observations of a clear seasonal variation in the onset of acute pancreatitis, we found no correlation between death due to acute pancreatitis and a specific month or season. Many prior studies have suggested that the majority of deaths in severe acute pancreatitis occur in the late phase of the disease as a result of pancreatic sepsis. Conversely, in the present study, the majority of affected individuals died during the very early phase of the disease. While gallstones represent the main etiologic factor in most larger clinical series, biliary etiology seems to play only a minor role in outpatient deaths undergoing medicolegal autopsies. Data derived from medicolegal autopsy studies should be included in future population-based studies of acute pancreatitis.     

Fatal crossbow injury in an adolescent

The authors present the case of a 14-year-old boy who died while handling a crossbow, which was a gift from a friend's mother. The bolt passed through the right nostril, penetrated the sinus sphenoidalis, the brain stem, the left occipital lobe and the occipital calvaria. Immediately after the accident, the victim was taken to a maximum care hospital. In spite of neurosurgical treatment and intensive care the victim died 4 days later. The case presented demonstrates that crossbows are not suitable as toys for underage persons, as they are deadly weapons which can cause serious penetrating injuries. In Germany, no license is required to buy and/or possess crossbows. In the authors' opinion, legal restrictions on the sale of crossbows and a special training of the users would be reasonable measures to reduce such accidents.