Image analysis as an adjunct to sodium rhodizonate test in the evaluation of gunshot residues: an experimental study

It is important to investigate the clothing, as well as the body, to determine the range of fire of entry wounds in firearm injuries. Clothing can affect the amount of gunshot residues (GSR) reaching the body and their distribution. The amount and distribution of the GSR also vary according to the distance between the firearm and the target. Sodium rhodizonate test provides valuable data when clothing is available for examination. In the absence of clothing, light microscopic examinations may add additional information regarding the range of fire. In this study, a sodium rhodizonate test was done on 80 garment samples containing the bullet entrance. The 80 calfskin samples were processed histologically and were stained using Alizarin Red S. These were also evaluated with computer-assisted image analysis. Gross residues were seen on military camouflage clothing in samples from < or = 45-cm group. White flannel undershirts under the military camouflage contained rhodizonate-positive particles only around the contact wounds. With image analysis, however, the residues could be detected also in the skin samples of the 2.5-cm- and 5-cm-range groups. We suggest that the image analysis can be combined with other techniques and it can provide valuable data in the determination of entry wounds and also in the estimation of firing distance.     

Computerized Image Analysis in Differentiation of Skin Lesions Caused by Electrocution, Flame Burns, and Abrasion

Abstract:  In the practice of forensic science, sometimes, it is not easy to understand whether skin lesion is due to electrocution and to differentiate the thermal burns and abrasion-type lesions, especially when electricity source cannot be revealed by death science investigation. Based on the causes of the lesions, cases were classified into three groups. Group 1 included 30 deaths from electrocution. Group 2 included 30 deaths with flame burns. Group 3 included 30 deaths from traffic accident cases, which had abrasions. In this study, epidermal nuclear area, perimeter, nuclear form factor, nuclear minimum axes, nuclear maximum axes, and minimum axes/maximum axes ratio were measured. As a result, we think that computerized image analysis beside light microscopic examination can be useful in the differentiation of the electrocution, flame burn, and abrasion type lesions.     

Distribution of surplus in sequential bargaining with endogenous recognition

I examine a sequential bargaining situation in which agents contest the right to propose an allocation. The contest can either take place at a pre-bargaining stage, yielding “persistent recognition” to propose, or recur throughout the bargaining, yielding “transitory recognition”. Equilibrium analysis reveals that surplus is distributed more unequally under persistent recognition; social cost is higher under persistent recognition if and only if it attracts a sufficient number of “active” bargainers; and individual’s incentive to propose under transitory recognition may actually increase in the number of agents, while this incentive always diminishes under persistent recognition.     

STR and SNP analysis of human DNA from Lucilia sericata larvae's gut contents

Importance of forensic entomology becomes inevitable when come across some incident where corpse is unidentifiable and lot of maggots or other insects are present. The most common application of forensic entomology is to use insects for the identification of specimens or human remains. DNA analysis recovered from a larva's gut contents can be used to identify a missing body. The obtained human STR and SNP profile support the association of a maggot to a specific patients or corpse. Main aim of this research was the identification of human DNA from gut contents of third instar maggots (larvae of Lucilia sericata) placed on diabetic patient's wounds for treatment purpose. Maggots (8–15) were taken from each diabetic patients (no. of the patients 8) and DNA was extracted from the gut contents manually by using Qiagen tissue protocol. Agarose gel electrophoresis was performed and the total size of DNA was seen using UV transilluminator. PCR amplification, STRs and SNPs profiling was then performed using PCR 9700 and AmpFLSTR Identifiler and SnaPshot Multiplex Kit (Applied Biosystems) respectively. The results were analyzed on ABI 310. SNP profiles were good and identifiable compared to the STRs where amplification was poor and the peaks were low. This may be the fact of the enzymatic activity present in the gut of the larvae which cause tremendous reduction in DNA size and thus yield. The results of this study reveals that it is possible to obtain a complete human profile using STRs and SNPs even if DNA is recovered from gut contents of maggots.