A new approach to amino acid racemization in enamel: testing of a less destructive sampling methodology

Aspartic acid racemization has been found to be an accurate measure of age at death for recent forensic material. This paper examines the practicality of using acid etching of the tooth surface to extract amino acids from the enamel for racemization analysis. By serial etching of the tooth and contamination of the teeth with bovine serum albumin prior to etching, the ability of etching to remove contamination was assessed. The destructiveness of the method was visualized and quantified using micro-computed tomography (micro-CT). By bleaching the teeth and by deeper etching it was possible to obtain more consistent values. While etching had little effect on the enamel at the macroscale, it did have an impact at the microscale. The quantities of enamel removed varied depending upon the tooth morphology, but were not large. Acid etching of enamel thus appears to be a promising new method for extracting proteins for amino acid racemization age estimation noninvasively.     

Further investigation of findings reported for the Minnesota sex offender screening tool-revised

Among a number of widely used risk assessment instruments with adult sexual offenders, the Minnesota Sex Offender Screening Tool-Revised (MnSOST-R) has been subject to relatively few evaluation studies. Only two independent research groups have published replication studies in the peer-reviewed literature with data not provided by the MnSOST-R's developers, and the results regarding the accuracy of predicting sexual recidivism have been mixed. In this article, important differences between the Barbaree et al. and Langton et al. studies are presented. Analyses reported for the various subsets comprising these two samples indicate that coding discrepancies in the Barbaree et al. study account for the different findings, with a moderate level of predictive accuracy using the Receiver Operating Characteristic curve ultimately found for the MnSOST-R in both data sets.     

The Formal Divide: Customary Rights and the Allocation of Credit to Agriculture in Tanzania

It is generally held that one mechanism to enable inclusive growth in Tanzania is enabling farmers to access credit to raise productivity and incomes. The formalisation of property rights in Tanzania is being undertaken by a multiplicity of actors at great expense to donors, individuals and the government. While there have been a variety of different justifications for allocating Certificates of Customary Rights of Occupancy (CCROs) to farmers in Tanzania, perhaps the most prominent argument is that it will enable farmers to finally overcome the divide between ‘informal’ customary rights and the formal banking sector. CCROs would provide the collateral that would induce banks to lend money to small-scale farmers. As part of a six-year investigation in Manyara, Mbeya and Dodoma regions, our research team evaluated the impact of formalisation on farmers’ access to credit. The paper will present the results while pointing to the continuing institutional and market imperfections that perpetuate the formal divide.     

The Politics of Obstruction: Republican Holds in the U.S. Senate

A defining feature of the modern US Senate is obstruction. Almost all pieces of legislation considered in the Senate are affected either directly or indirectly by obstruction. Obstruction takes many forms in the modern Senate, but one of the most prevalent, yet least studied, is the hold. Using a newly created dataset on Republican Senate holds, we cast light on this important practice. Our results suggest that a variety of factors including timing, party status, and a senator's voting record are related to both the prevalence of holds and the success of legislation subject to holds in the Senate.     

Is PCL-R psychopathy associated with either type or severity of personality disorder?

The extent to which assessment of personality disorders (PDs), and trans-diagnostic measures of PD severity, can capture the variance in psychopathy measured by the Psychopathy Checklist-Revised (PCL-R) was examined in 100 forensic patients with a history of violent offending. Correlational and linear regression analyses were carried out to establish whether (i) combinations of PDs would predict PCL-R scores for each of its two factors, interpersonal–affective (F1) and antisocial deviance (F2); (ii) ‘acting out’, a putative measure of externalising maladjustment that transcends PD categories, would predict PCL-R scores. Results showed that narcissistic and avoidant PDs contributed significantly to the prediction of F1, but only antisocial PD contributed to the prediction of F2. ‘Acting out’ predicted both F1 and F2, suggesting that core features of PCL-R psychopathy are embedded within and across different PD diagnoses. Results are discussed in relation to different sub-types of psychopathy described in the literature.