Developmental factors related to deviant sexual preferences in child molesters

The aim of this study was to investigate the relationship between developmental factors and deviant sexual preferences in child molesters. In total, 146 adult males having committed a sexual offence against a child were included in the study. Three types of factors were investigated: negative experiences during childhood, behavior problems during adolescence, and sexual criminal activity in adulthood. Negative experiences and behavior problems were assessed through a semistructured interview. The sexual criminal activity was determined using police records. Sexual preferences towards children were assessed using phallometric assessment. Hierarchical regression analyses suggested the presence of two developmental pathways. The psychosocial deficits pathway is related to a sexual interest for nonviolent sexual stimuli involving children. The sexualization pathway is associated with a sexual interest for violent sexual stimuli involving children. These two pathways are discussed in light of previous empirical findings related to the development of deviant sexual preferences in child molesters.     

NIST bullet signature measurement system for RM (Reference Material) 8240 standard bullets

A bullet signature measurement system based on a stylus instrument was developed at the National Institute of Standards and Technology (NIST) for the signature measurements of NIST RM (Reference Material) 8240 standard bullets. The standard bullets are developed as a reference standard for bullet signature measurements and are aimed to support the recently established National Integrated Ballistics Information Network (NIBIN) by the Bureau of Alcohol, Tobacco and Firearms (ATF) and the Federal Bureau of Investigation (FBI). The RM bullets are designed as both a virtual and a physical bullet signature standard. The virtual standard is a set of six digitized bullet signatures originally profiled from six master bullets fired at ATF and FBI using six different guns. By using the virtual signature standard to control the tool path on a numerically controlled diamond turning machine at NIST, 40 RM bullets were produced. In this paper, a comparison parameter and an algorithm using auto-and cross-correlation functions are described for qualifying the bullet signature differences between the RM bullets and the virtual bullet signature standard. When two compared signatures are exactly the same (point by point), their cross-correlation function (CCF) value will be equal to 100%. The measurement system setup, measurement program, and initial measurement results are discussed. Initial measurement results for the 40 standard bullets, each measured at six land impressions, show that the CCF values for the 240 signature measurements are higher than 95%, with most of them even higher than 99%. These results demonstrate the high reproducibility for both the manufacturing process and the measurement system for the NIST RM 8240 standard bullets.     

FACE Facts: Why Human Genetics Will Always Provoke Bioethics

Some people dispute the relative importance of issues in genetics and biotechnology for the future of bioethics, either because they think the problems are time-limited or because they give priority to issue of human rights and social justice in health care. In fact, the special historical standing of genetic issue s in bioethics reflects four overlapping sources of moral sensitivity which ar inherent in the stories that genetic science tells and raise paradigmatic justice concerns: the implications of new genetic knowledge for people's understanding of their familial roles, ancestral origins, community memberships, and ethnic affiliations. Beneath worries over "genetic privacy," "the therapeutic gap," and the "post-human," this constellation of basic wellspring which both insures and justifies a central place for genetics on the agenda of bioethics.     

Capillary electrophoretic analysis of phosphorus species in clandestine methamphetamine laboratory samples

The clandestine manufacture of methamphetamine is a spreading epidemic. Manufacturing methods are constantly changing, necessitating the implementation of new analytical tools to identify materials from these labs. Characterization of phosphate, phosphite, and hypophosphite ions is necessary to distinguish the various phosphorus-iodine manufacturing methods that are popular methods for reducing pseudoephedrine to methamphetamine. This work describes a capillary electrophoresis method to separate acetate, azide, bromide, carbonate, chlorate, chloride, chromate, fluoride, hypophosphite, iodide, nitrate, nitrite, perchlorate, phosphate, phosphite, sulfate, sulfite, and thiocyanate. The CElixerOA 8.2 dynamic coating system was modified by lowering the capillary temperature to 15 degrees C and using an acid flush between runs to remove adsorbed materials. This allows detection of ions down to between 10 and 30 parts per million with percent relative standard deviations of normalized migration times under 0.1%. This method is a valuable tool for the characterization of phosphate, phosphite, and hypophosphite in routine analysis of clandestine methamphetamine manufacturing evidence and has a broader application in other areas of forensic analysis.     

Simultaneous determination of total human and male DNA using a duplex real-time PCR assay

A single duplex assay to determine both the amount of total human DNA and the amount of male DNA in a forensic sample has been developed. This assay is based on TaqMan technology and uses the multicopy Alu sequence to quantitate total human DNA and the multicopy DYZ5 sequence to quantitate Y chromosomal (male) DNA. The assay accepts a wide concentration range of input DNA (2 muL of 64 ng/microL to 0.5 pg/microL), and also allows detection of PCR failure. The PCR product sizes Alu (127 bp) and DYZ5 (137bp) approximate that of the smaller short tandem repeats (STRs) which should make the assay predictive of STR success with degraded DNA. The assay was optimized for probe/primer concentrations and BSA addition and validated on its reproducibility, on its human specificity, on its nonethnic variability, for artificial mixtures and adjudicated casework, for the effect of inhibitors and for state of DNA degradation. This assay should prove very usual in forensic analyses because knowing the relative amounts of male versus female DNA can allow the examiner to decide which samples may yield the most probative value in a case or direct the samples to methods that would yield the greatest information.     

DNA analysis of digested tomato seeds in stomach contents

Examination of stomach contents is one of the important steps in medical legal autopsy. Vegetative materials such as stems, roots, and seeds in stomach contents can be valuable evidence for providing investigative leads in death investigation. Currently, the identification of plant materials relies on microscopic and morphologic examination. We have found that many seeds are often protected from acid degradation during stomach digestion by their tough exterior seed coat. Tomato seeds were selected as a model system to assess DNA analysis and plant variety marker identification. The DNA-amplified fragment length polymorphism method was performed to determine if the DNA obtained from single seeds could be used for PCR analysis. From the amplified fragment length polymorphism results, some candidate markers for individualizing seeds from morphologically distinct tomatoes were identified. These data on DNA analysis of tomato seeds indicate amplified fragment length polymorphism is a viable procedure for the individualization of seeds from stomach contents in forensic investigations.     

Gender, Threat/Control-Override Delusions and Violence

This study brings together the threat/control-override perspective and the literature on gender and stress coping to argue that gender moderates the association between threat delusions and violence. We suggest that men are more likely than women to respond to stressors such as threat delusions with violence. We test these ideas using data from the MacArthur Violence Risk Assessment Study, a multi-wave study of post-discharge psychiatric patients. Within-person results from two-level hierarchical models support the idea that men and women cope with threat delusions differently. Specifically, we find that men are significantly more likely to engage in violence during periods when they experience threat delusions, compared with periods when they do not experience threat delusions. In contrast, women are significantly less likely to engage in violence during times when they experience threat delusions, compared with periods when they do not. We discuss these findings in light of the literature on gender and stress coping.     

The case of the unreliable SNP: recurrent back-mutation of Y-chromosomal marker P25 through gene conversion

The Y-chromosomal binary marker P25 is a paralogous sequence variant, rather than a SNP: three copies of the P25 sequence lie within the giant palindromic repeats on Yq, and one copy has undergone a C to A transversion to define haplogroup R1b (designated C/C/A). Since gene conversion is known to be active in the palindromic repeats, we reasoned that P25 might be liable to back-mutation by gene conversion, yielding the ancestral state C/C/C. Through analysis of a set of binary markers in Y-chromosomes in two large samples from Great Britain and the Iberian Peninsula we show that such conversion events have occurred at least twice, and provide preliminary evidence that the reverse conversion event (yielding C/A/A) has also occurred. Because of its inherent instability, we suggest that P25 be used with caution in forensic studies, and perhaps replaced with the more reliable binary marker M269.