Childhood Violence Exposure: Cumulative and Specific Effects on Adult Mental Health

Childhood exposure to violence and victimization is a significant public health problem, with potentially long-lasting, deleterious effects on adult mental health. Using a longitudinal study design, 123 young adults—identified in adolescence as at-risk for high school dropout—were examined for the effects of multi-domain childhood victimization on emotional distress and suicide risk, net of adolescent risk and protective factors, including family dysfunction. The hypothesis that higher levels of cumulative childhood victimization would be significantly associated with mental health maladjustment in young adulthood was confirmed by the analysis. However, the victimization predictors of adult emotional distress were different than the predictors of adult suicide risk. These findings indicate the need for prevention and intervention approaches that include thorough assessment, and focus on the childhood and adolescent problem areas that are most consequential for long-term psychological well-being.     

Recovery of DNA and fingerprints from touched documents

This study investigated the various factors affecting DNA profiling from DNA recovered from fingerprints deposited on paper before and after fingerprint enhancement treatments. The DNeasy^® plant mini kit (QIAGEN^®) was found to improve DNA recovery from paper by over 150% compared with the QIAamp^® mini kit. A significant decrease in the amount of DNA recovered was observed following treatment with DFO and/or Ninhydrin. This decrease in yield did not have a comparably significant effect on the quality of the SGM Plus™ profiles. Furthermore, this study found that whilst certain paper types, such as newspaper, magazine and filter paper allowed for the good recovery of DNA, common office paper and white card, strongly interfered with the recovery of DNA resulting in poor quality profiles.     

Validation of Large White Pig as an animal model for the study of cannabinoids metabolism: application to the study of THC distribution in tissues

This study presents a new animal model, the Large White Pig, which was tested for studying cannabinoids metabolism. The first step has focused on determination of plasma kinetics after injection of Delta(9)-tetrahydrocannabinol (THC) at different dosages. Seven pigs received THC by intravenous injections (50, 100 or 200 microg/kg). Plasma samples were collected during 48 h. Determination of cannabinoids concentrations were performed by gas chromatography/mass spectrometry. Results showed that plasma kinetics were comparable to those reported in humans. Terminal half-life of elimination was 10.6 h and a volume of distribution of 32 l/kg was calculated. In a second step, this model was used to determine the kinetic profile of cannabinoids distribution in tissues. Eight Large White male pigs received an injection of THC (200 microg/kg). Two pigs were sacrificed 30 min after injection, two others after 2, 6 and 24 h. Different tissues were sampled: liver, kidney, heart, lung, spleen, muscle, fat, bile, blood, vitreous humor and several brain areas. The fastest THC elimination was noted in liver tissue, where it was completely eliminated in 6 h. THC concentrations decreased in brain tissue slower than in blood. The slowest THC elimination was observed for fat tissue, where the molecule was still present at significant concentrations 24 h later. After 30 min, THC concentration in different brain areas was highest in the cerebellum and lowest in the medulla oblongata. THC elimination kinetics noted in kidney, heart, spleen, muscle and lung were comparable with those observed in blood. 11-Hydroxy-THC was only found at high levels in liver. THC-COOH was less than 5 ng/g in most tissues, except in bile, where it increased for 24 h following THC injection. This study confirms, even after a unique administration, the prolonged retention of THC in brain and particularly in fat, which could be at the origin of different phenomena observed for heavy users such as prolonged detection of THC-COOH in urine or cannabis-related flashbacks. Moreover, these results support the interest for this animal model, which could be used in further studies of distribution of cannabinoids in tissues.     

The use of mitochondrial cytochrome oxidase I gene (COI) to differentiate two UK blowfly species -- Calliphora vicina and Calliphora vomitoria

Traditionally identification of forensically important insects has been carried out based upon morphological differences between species. However insect evidence found at a crime scene may on occasion be difficult to distinguish by morphological techniques and under these circumstances another method of accurate identification is required. This work utilises a cytochrome oxidase I partial mitochondrial gene region (COI) to distinguish the two of the main UK blowfly species -- Calliphora vicina (Robineau Desvoidy) and Calliphora vomitoria (Linnaeus) (Diptera:Calliphoridae). Seventeen interspecific differences in COI sequence were located. Use of the restriction enzyme SfcI on this gene region provides a simple method for distinguishing between C. vicina and C. vomitoria.     

Interviewing Preschoolers: Comparisons Of Yes/No and Wh- Questions

This study investigated the influence of question format on preschool-aged children's errors, their response accuracy, and their tendency to say I don't know when given non-misleading questions in a neutral, unbiased context. Children (3 to 5 years old) participated in a craft-making session that included a staged accident with two experimenters differing in gender and appearance; the environment also had several distinctive features. One week later children were interviewed about actions, participants, and environment; questions were yes/no format with the veridical response yes (yes questions), yes/no format with the veridical response no (no questions), and specific wh- format questions. Question format substantially influenced children's responses: they were most likely to make errors if asked no questions, and were unlikely to answer either yes/no question with I don't know. In contrast, children spontaneously and frequently said I don't know to wh- questions about content they did not recall (environment), but not about content that was well recalled (actions). Implications of question format for reliability of eyewitness testimony by preschoolers are discussed.     

THE IMPACTC OF DIVORCE ON FAMILIES

Australian research on the impact of separation and divorce on children and their families has consistently shown that although separation is a stressful event in the lives of families, the long-term prospects for these families is encouraging. A number of issues arising from the research presented in this article warrant closer consideration by decision makers, court administrators, and professionals dealing with disputing families. First, programs aimed at reducing conflict and assisting families to deal with the emotional impact of separation need to be given priority. Second, there is sufficient indication to suggest that poverty as a result of separation and divorce has a debilitating effect on women and children. Third, in dealing with disputes over custody and access, care needs to be taken to respect the needs of individual children. Finally, high conflict in a family postseparation should be a warning to pay particular attention to the potential harm of applying joint custody and frequent access presumptions.     

Comparison of presumptive blood test kits including hexagon OBTI

Four presumptive blood tests, Hexagon OBTI, Hemastix(R), Leucomalachite green (LMG), and Kastle-Meyer (KM) were compared for their sensitivity in the identification of dried bloodstains. Stains of varying blood dilutions were subjected to each presumptive test and the results compared. The Hexagon OBTI buffer volume was also reduced to ascertain whether this increased the sensitivity of the kit. The study found that Hemastix(R) was the most sensitive test for trace blood detection. Only with the reduced buffer volume was the Hexagon OBTI kit as sensitive as the LMG and KM tests. However, the Hexagon OBTI kit has the advantage of being a primate specific blood detection kit. This study also investigated whether the OBTI buffer within the kit could be utilized for DNA profiling after presumptive testing. The results show that DNA profiles can be obtained from the Hexagon OBTI kit buffer directly.