Recovering obliterated laser engraved serial numbers in firearms

An easy procedure for recovering obliterated firearms serial numbers, which are laser engraved is presented in this case report. For these serial numbers, the traditional recovering method using acid etching generally fails, once marking the serial number does not necessarily imply a deep permanent deformation of the crystalline array. The standard required mirror-like finish of the surface commonly can destroy any evidence of the original serial number, i.e., can destroy the heat affected zone (HAZ) of only few micra, if it is still present. It is shown in this report that relief polishing and reflected light stereomicroscopy can, in certain cases, successfully reveal obliterated serial numbers, originally marked by laser. The use of this procedure for recovering this type of obliterated serial number is illustrated and discussed with an example we have dealt with.     

Spatio-Temporal Interaction of Urban Crime

Over the past decade, a renewed interest in the analysis of crime hot-spots has emerged in the social and behavioral sciences. Spurred by improvements in computing power, data visualization and geographic information systems, numerous innovative approaches have materialized for identifying areas of elevated crime in urban environments. Unfortunately, many hot-spot analysis techniques treat the spatial and temporal aspects of crime as distinct entities, thus ignoring the necessary interaction of space and time to produce criminal opportunities. The purpose of this paper is to explore the utility of statistical measures for identifying and comparing the spatio-temporal footprints of robbery, burglary and assault. Functional and visual comparisons for spatio-temporal clusters are analyzed across a range of space–time values using a comprehensive database of crime events for Cincinnati, Ohio. Empirical results suggest that robbery, burglary and assault have dramatically different spatio-temporal signatures.

The analysis of biological samples from crime scene for a future human DNA profile confrontation. Effects of presumptive test reagents on the ability to obtain STR profiles for human identification

Because of the increase of evidence of blood stains, that have been washed or cleaned in an attempt to mask the analysis of DNA profiles, there is also an increase in the use of presumptive tests on samples sent to laboratories. Some of the presumptive tests, used to identify blood and semen stains, could potentially affect the recovery of high molecular weight DNA from the samples, or extinguish them, especially those already present in small quantities. After the presumptive tests, often these samples are discarded. This study aimed to examine the possibility of obtaining a DNA profile from samples submitted for presumptive testing and cleaned with bleaches with and without chlorine. Two different protocols were conducted: (a) A unique sample of human blood in natura (5 μL), already typed through the DNA techniques with the genetic profile previously known (control), was distributed onto cotton fabrics and dried at room temperature. Four samples of fabric were macerated in saline solution and Coombs serum and then stored for three months (room temperature and freezer −20 °C). (b) Another sample of human blood, type A, in natura, already typed through the techniques of DNA (control) was used. Aliquots of 200 μL were distributed in: cotton, denim and synthetic fabric. The samples were dried at room temperature for 24 h. The blood stains in those fabrics (cotton, denim and synthetic) were then divided into three groups: unwashed, cleaned with chlorine bleach and cleaned with chlorine bleach and soap powder. The samples were again dried at room temperature for 24 h, before the use of luminol. The DNA were extracted with Chelex 100 and amplified with the Identifiler Kit (Applied Biosystems). The blood stains exposed to saline and Coombs serum had DNA profiles consistent with untreated samples (controls). This result shows that the experts should keep and store the samples treated with saline and Coombs serum for future DNA confrontation when necessary. Also discussed in this paper the pattern of blood stains after washing with bleaching solutions, as well as the quantity of DNA obtained from these samples.     

Crime, economic conditions, social interactions and family heritage

This paper tests whether factors referring to socio-economic aspects, family heritage, social interaction, habits and customs explain differences among violent and non-violent prisoners. Some of the results of the probit estimation show that economic issues are the main factors that stimulate the practice of non-violent crime. On the other hand, violent crimes results suggest that factors related to family heritage reduce this kind of crime. In relation to variables of social interaction, prisoners who were brought up in a good neighborhood have a lower probability of committing violent crimes.     

Assessing treatment readiness in violent offenders

Although violent offenders are widely considered to be difficult to engage in therapeutic change, few methods of assessing treatment readiness currently exist. In this article the validation of a brief self-report measure designed to assess treatment readiness in offenders who have been referred to violent offender treatment programs is described. The measure, which is an adaptation of a general measure of treatment readiness developed in a previous work, displayed acceptable levels of convergent and discriminant validity and was able to successfully predict treatment engagement in violent offender treatment. These results suggest that the measure has utility in the assessment of treatment readiness in violent offenders.     

Death Caused by Toxic Epidermal Necrolysis (Lyell Syndrome)

Abstract: Toxic epidermal necrolysis (TEN) is characterized by fever, scalded appearance of the skin, and epidermolysis associated to blister formation and exfoliation, and it is caused by hypersensitivity reaction to a drug. The authors report two cases of death as a result of TEN; both referred to old aged women treated with a polytherapy including allopurinol. Both patients displayed erythematous skin lesions similar to scald burns and epidermolysis at the face, chest, and abdomen and died shortly after hospitalization. Autopsy findings and histological examinations revealed epidermal necrolysis and confirmed the clinical diagnosis. A strict time‐correlation between allopurinol administration and symptoms was evidenced. Because of its iatrogenic origin, TEN often arises suspicions of medical liability; however, because of its unpredictable nature, the occurrence of this syndrome cannot be ascribed to the medical staff whose main task is the rapid diagnosis and the correct management.