Performance characteristics of commercial Y-STR multiplex systems

In this work, a number of performance checks were carried out to evaluate the efficacy of commercial Y-short tandem repeats (Y-STR) kits for casework applications. The study evaluated the sensitivity, specificity and stability of the Y-STR markers used and the ability to obtain a male profile from postcoital samples taken at various time points after intercourse. All systems performed well with 1-3 ng of male DNA as recommended by the manufacturers. All systems gave full profiles at 100 pg of input DNA, which is within the realm of low copy number DNA analysis. Moreover all, except Y-Plex12, gave full profiles with 30-50 pg of male DNA. No increased performance was obtained with any of the systems by increasing the cycle number beyond that recommended by the various manufacturers. When up to 1 microg of female DNA was used (in the absence of male DNA) no female DNA cross reactivity was observed with the Y-Plex 12 and Y-Filer systems. PowerPlex Y produced female DNA derived products near the DYS438 and within the DYS392 loci at a rare allele position with high input DNA levels (300 ng and 1 microg, respectively). Male/female DNA admixture experiments indicated the particularly high specificity of the Y-Filer and PowerPlex Y systems under conditions of several thousand fold female DNA excess. All systems were able to detect the minor alleles in male/male DNA admixtures at a 1:5 dilution with the PowerPlex Y and Y-Filer being able to detect some minor alleles at 1:20. Species testing indicated some limited, minor cross reactivity of the commercial systems with some domestic male mammals although it is easily recognizable and would not pose any problems in casework analysis. As expected a significant number of cross-reacting products were obtained with nonhuman primate species. All Y-STR multiplex systems tested were able to produce complete Y-STR profiles from bloodstains and semen stains exposed up to 6 weeks when the samples were protected against precipitation and sunlight. However, exposure of the samples to precipitation either in the presence or absence of sunlight resulted in Y-STR profile loss over time, with total profile loss occurring with all systems after 3 weeks or more. Complete Y-STR profiles of the male donors up to 72 h postcoitus were obtained with all of the multiplex systems tested, except for Y-Plex12, which gave partial profiles.     

Simplified low-copy-number DNA analysis by post-PCR purification

Frequently, evidentiary items contain an insufficient quantity of DNA to obtain complete or even partial DNA profiles using standard forensic gentotyping techniques. Such low-copy-number (LCN) samples are usually subjected to increased amplification cylces to obtain genetic data. In this study, a 28-cycle polymerase chain reaction (PCR) was used to evaluate various methods of post-PCR purification for their effects on the sensitivity of fluorophore-based allelic detection subsequent to capillary electrophoretic separation. The amplified product was purified using filtration, silica gel membrane, and enzyme mediated hydrolysis purification techniques and evaluated for their effect on fluorescent allelic signal intensity. A purification method was selected and its effect on fluorescent allelic signal intensity was compared with that of the unpurified PCR product. A method of post-PCR purification is described which increases the sensitivity of standard 28-cycle PCR such that profiles from LCN DNA templates (<100 pg DNA) can be obtained. Full DNA profiles were consistently obtained with as little as 20 pg template DNA without increased cycle number. In mock case type samples with dermal ridge fingerprints, genetic profiles were obtained by amplification with 28 cycles followed by post-PCR purification whereas no profiles were obtained without purification of the PCR product. Allele dropout, increased stutter, and sporadic contamination typical of LCN analysis were observed; however, no contamination was observed in negative amplification controls. Post-PCR purification of the PCR product can increase the sensitivity of capillary electrophoresis to such an extent that DNA profiles can be obtained from <100 pg of DNA using 28-cycle amplification.     

Ten methods for calculating the uncertainty of measurement

While forensic laboratories are coming under increasing pressure to provide meaningful estimates of measurement uncertainty, there has been little discussion of this topic in the literature. This article summarizes ten bases for estimating this parameter: (1) proficiency tests; (2) readability limits; (3) independent reference materials; (4) operational limits applied during calibration; (5) expert judgment; (6) precision control samples without (6) and with (7) contributions from extramural sources of error; (8) error budgets; (9) historical performance; and (10) ruggedness tests. Based on the assumptions underlying each approach, the forensic community will need to apply a variety of discipline-specific approaches to arrive at satisfactory estimates of measurement uncertainty.     

Experiences of Incarcerated Veterans in an All-Veterans Housing Unit: a Qualitative Study

Many US veterans leave military service with a variety of psychosocial risk factors stemming from readjustment to civilian life, and there is increased public concern about the incarceration of veterans given ongoing conflicts in Iraq and Afghanistan. Prisons are playing instrumental roles in developing interventions to address the problems justice-involved veterans face both psychologically and environmentally in the form of veterans’ service units (VSUs), dormitories developed to assist with community reintegration, and connecting veterans to medical and mental health services. This study uses qualitative data from 87 veterans on a VSU who participated in a program improvement survey asking about their programming and reentry needs, experiences on the unit compared to other units, and any suggestions for improvement. Qualitative analysis of responses identified several themes including veterans’ needs around physical fitness, job training, education, and mental health and substance abuse treatment; positive experiences on the VSU compared to traditional units; the positive partnership role with the State Department of Corrections and the local Veterans Affairs (VA) medical center; and concerns on the unit about VA eligibility, combat status, and “real veterans.” These results are some of the first to capture the experiences of veterans on a VSU and the findings highlight potential benefits and challenges with implementing VSUs. Greater research and evaluation are needed to develop more treatment-oriented, rehabilitative models of justice and to continue to refine the VSU model.     

The effectiveness of supermarket posters in helping to find missing children

One approach used to help find missing children is to place posters of them at the exits of supermarkets. The present research addresses the question of how effective that approach is likely to be. Posters of 8 missing children were displayed on a bulletin board at a cooperating grocery store. Customers leaving the store completed a survey and took a recognition memory test for the children. Most customers thought the problem of missing children was an important issue. However, the majority of customers also reported either not looking at the posters or only briefly looking at the posters. Recognition memory for children depicted in the posters did not reliably differ from chance. It appears that there is much room for improvement when it comes to increasing the attention paid to posters meant to help find missing children.     

Coase and Bertrand on lighthouses

Coase (Journal of Low and Economics 17(2):185–213, 1974) failed to appreciate that the construction and maintenance of nineteenth-century lighthouses were in part financed by British taxpayers. Bertrand (Cambridge Journal of Economics 30:389–402, 2006) rightly calls him to account. While agreeing with Bertrand’s conclusion, we dispute her reasoning and argue that lighthouses nevertheless could have been supplied by the private sector.     

Someone has to do it: towards a practical defence of politicians

In response to rising popular disenchantment with elected officials, numerous scholars have sought to defend politics and restate why it matters. For the most part, however, these theoretical arguments overlook the views and reflections of politicians themselves. As a step towards filling this gap, the author surveys politician-centred studies from around the world and the reflections of academics who have become politicians. By paying careful attention to what ‘insiders’ say about life in politics, the author constructs a practical rather than theoretical defence of the vocation and the people who undertake it. The author argues that politicians' views remind one that human endeavour is central to the purpose and function of politics and associated political institutions. To link the practical views and experiences of politicians with the emerging literature on demonisation, the author revisits the work of Arendt and Weber. The author concludes that while one may not always like who politicians are or the ways they operate, revaluing endeavour allows one to give credit where credit is due; politicians may regularly disappoint people but representative democracy does not work without them.     

Westminster in small states: comparing the Caribbean and pacific experience

Small states, and those in the Caribbean and Pacific regions in particular, are among the most stubbornly and disproportionally democratic countries in the world. And yet, they are rarely studied comparatively, despite sharing seemingly obvious similarities – aside from being small island states with developing economies they also tend to share a British colonial heritage and Westminster-inspired political institutions. This omission is all the more puzzling if we consider that the group does not conform to the standard battery of explanations developed by democratization theorists. To pave the way for further research across these two regions, this article provides a synoptic comparison of the process of democratization in Caribbean and Pacific small states. We highlight important similarities and differences that stem from the interaction between formal institutions and informal practices. We conclude by reiterating the benefits for scholars of democratization by looking at these significant yet hitherto rarely compared cases.     

Public Attitudes Toward Immigration Policy Across the Legal/Illegal Divide: The Role of Categorical and Attribute-Based Decision-Making

Scholars debate the relative strength of economic and ‘socio-psychological’ sources of anti-immigrant sentiment. However, the literature often fails to distinguish legal from illegal immigration and therefore overlooks a major instance in which this debate is moot. To address this issue, we develop a theory that recognizes two different modes of evaluating immigrants: “attribute-based” judgment, in which respondents weigh immigrants’ desirability based on individual characteristics—human capital, race, language ability, and so on—and “categorical” judgment, which disregards these altogether. Categorical judgments arise when a policy issue triggers blanket considerations of justice or principle that obviate considerations about putative beneficiaries’ individual merits, instead evoking overriding beliefs about the desirability of the policy as a whole or casting the entire category as uniformly deserving or undeserving. We use experimental evidence from two national surveys to show that the principal distinction between attitudes toward legal and illegal immigration is not in the relative weight of immigrants’ attributes but the much greater prevalence of categorical assessments of illegal immigration policy, much of it rooted in rigid moralistic convictions about the importance of strict adherence to rules and laws.     

Conference on Business Crime,Fraud and Corruption England,March/April 1991 Preliminary Call for Papers

Conference on Business Crime, Fraud and Corruption England, March/April 1991 Preliminary Call for Papers