Cell free DNA as a component of forensic evidence recovered from touched surfaces

In the course of a criminal investigation, DNA is often recovered from items that have been handled by an individual. Whilst there have been studies investigating the propensity of different individuals to deposit DNA, little is known about the factors involved in the transference of DNA through touch. This investigation seeks to clarify some of the underlying processes involved in DNA transfer, as to better understand the significance of so-called “touch DNA” evidence (tDNA). It was shown that an average yield of 11.5 ng of DNA could be recovered from 1 mL cell-free sweat samples leading to the hypothesis that cell-free nucleic acids (CNAs) of a suitable length for standard DNA profiling are transferred during handling/touching items. A method of standardization of tDNA deposition was developed to overcome the significant sample to sample variability in DNA levels characteristic of tDNA samples. The glass bead method allowed the creation of identical tDNA sample sets, thus permitting direct comparisons to be made in the efficiency of various extraction methods. Extraction methods designed to optimize CNA recovery from touched articles resulted in comparable yields in a general population study, however the methods resulted in a twofold increase in DNA yields from touched items touched by individuals with sweaty hands. These results suggest that the CNA component of touched surfaces should be included to maximize profiling success of tDNA.     

An investigation of model forensic bone in soil environments studied using infrared spectroscopy

Infrared spectroscopy has been used to examine changes to bone chemistry as a result of soil burial. Pig carcasses were buried as part of a controlled field study, and pig bone was used in soil environments established in the laboratory. The variables of species type, bone pretreatment, soil type and pH, moisture content, temperature, and burial time were investigated. The crystallinity index (CI) and the organic and carbonate contents of the bones were monitored. The data revealed decreasing trends in the organic and carbonate contents and an increase in the CI of the bone with burial time. An acidic soil environment and soil type are the factors that have the most influence on bone chemistry as a result of burial. The study demonstrates the potential of infrared spectroscopy as a straightforward method of monitoring the changes associated with aging of bones in a variety of soil environments.     

The Optimal Combination of Cartilage Source and Apparatus for Long‐Term In Vitro Chondrocyte Viability Analysis

Abstract: Most studies of long‐term chondrocytes survival were for tissue banks. They showed a gradual reduction in the viable chondrocytes percentage as a function of time and ambient temperature, but the samples were harvested under optimal conditions. The aim of our study was to determine the most reliable combination of cartilage source and assay for the in vitro postmortem chondrocyte viability analysis in the conditions that imitate a dead body. Osteochondral cylinders were procured from femoral condyles and talar trochleas of three male donors and stored in the cell culture media at 4 ± 2°C and 23 ± 2°C. The samples were analyzed by a cell viability analyzer and a confocal laser scanning microscope (CLSM) initially 24–36 h after death and then in 4‐week intervals. The results reconfirmed the significant influence of time (p = 0.0002), but not of the temperature (p = 0.237). The largest reproducibility was presented for the knee joint and the CLSM.     

Characterization of the triacylglycerol crystal formation in adipose tissue during a vehicle collision

The unusual appearance of crystalline fat structures was observed during the postmortem examination of a motor vehicle accident victim. The crystal structures were characterized using Fourier transform infrared spectroscopy and x-ray diffractometry. The structures were found to be made of triacylglycerols, a dominant lipid structure found in human adipose tissue, capable of forming various polymorphic structures. The morphology of the crystalline material was found using both techniques to be predominantly the beta' form of triacylglycerols. The accelerated growth of such triacylglycerol morphology has been observed as a result of shear stresses in other studies involving edible fats. As a result of the findings of this study, it is proposed that increased shear forces may be responsible for the formation of the unusual fat structure found in the victim. An understanding of the effect of forces on the structure of body fat in high-impact collisions can potentially assist in verifying a high-velocity impact.     

Fatal intoxication with tianeptine (Stablon)

Tianeptine (Stablon), although structurally similar to tricyclic antidepressants, acts by enhancing the reuptake of serotonin. A fatal case is presented involving a 26-year-old man, found lying in bed with a "mushroom of foam" around his mouth. Empty blister packs of Stablon and a suicide note were found next to the body. A liquid-liquid extraction procedure with n-hexane: ethyl acetate and n-hexane: 2-propanol, followed by LC-DAD-MS analysis, using positive mode electrospray ionization was performed. The detection limit was 0.001 microg/mL. The toxicological results revealed the following tianeptine concentrations in the post-mortem samples: blood 5.1 microg/mL; urine 2.0 microg/mL; liver 23 microg/g; stomach contents 22 mg. Femoral blood analyses also revealed an ethanol concentration of 0.53 g/L. The present method was also developed and validated for the other post-mortem specimens, since no previous published data had confirmed the post-mortem distribution of tianeptine. The absence of other suitable direct causes of death (macroscopic or histological) and the positive results achieved with the toxicological analysis led the pathologist to rule that death was due to an intoxication caused by the suicidal ingestion of tianeptine in combination with alcohol.     

Predictors of adult attitudes toward corporal punishment of children

This study identifies predictors of favorable attitudes toward spanking. Analyses were performed with survey data collected from a representative sample of 1,000 adults from Quebec, Canada. According to this survey, a majority of respondents endorsed spanking, despite their recognition of potential harm associated with corporal punishment (CP) of children. The prediction model of attitudes toward spanking included demographics, experiencing or witnessing various forms of family violence and abuse in childhood, and perceived frequency of physical injuries resulting from CP. Spanking was the most reported childhood experience (66.4%), and most violence and abuse predictors were significantly and positively correlated. Older respondents who were spanked in childhood and who believed that spanking never or seldom results in physical injuries were the most in favor of spanking. On the other hand, respondents who reported more severe physical violence or psychological abuse in childhood were less in favor of spanking. Findings are discussed in terms of prevention of CP and family coercion cycle.     

Subdural Hematoma Rebleeding in Relation to Abusive Head Trauma

When cases of suspected abusive head trauma are adjudicated in courts of law, one of the theories often presented by defense experts is that a normal, healthy infant or child suddenly neurologically deteriorates or dies several weeks to months after birth or minor injury because a preceding subdural hematoma spontaneously rebleeds after a minor traumatic event. This article reviews the underlying scientific basis of subdural hematoma rebleeding as it applies to this courtroom theory.     

Between Cold War Imperatives and State-Sponsored Terrorism: The United States and “Operation Condor”

Operation Condor was a transnational network of organized state-sponsored terrorism that targeted Communist “subversion.” It was operational in the second half of the 1970s. The key member countries were Chile, Argentina, Uruguay, Bolivia, Paraguay, and Brazil (Peru and Equador joined the network later on, with a more marginal role). Based on declassified documents from the United Nations High Commissioner for Refugees in Geneva and on U.S. documents of various origin, this article will assess the development of the Condor network and the U.S. reaction to such manifest acts of state-sponsored terrorism.