In vitro production of GHB in blood and serum samples under various storage conditions

The in vitro production of GHB was observed in freshly collected, untreated whole blood samples using glass BD-Vacutainers and polypropylene S-monovettes. GHB concentrations were determined daily over a period of one week and after 3, 6 and 9 weeks again. Furthermore, the GHB concentration in 40 untreated random whole blood samples stored at 4°C for a longer period of time (10 samples 12 month, 10 samples 24 month and 20 samples 36 month) was also determined. For comparison, the in vitro production of GHB in freshly collected and prepared serum samples was observed. GHB serum concentrations were determined three times over a period of one week and once again after six weeks. Sample preparation was performed by means of methanolic extraction following the precipitation of whole blood and serum samples. A methanolic standard calibration was done in a low range of 0.005-0.1 μg/mL (LOD: 0.004, LLOQ: 0.013). For quantification a spiked blood bank serum with a determined GHB concentration of 0.09 μg/mL was used. Corrected calibrations in the range of 0.09-5.09 μg/mL were used (LOD: 0.08 μg/mL, LLOQ: 0.30 μg/mL), recovery: 91.3% (high level: 4.09 μg/mL) 50.5% (low level: 0.19 μg/mL). RESULTS: Relevant elevation of GHB was observed in all whole blood samples stored in liquid form (4°C or room temperature). In two of the 40 whole blood samples stored over a longer period of time at 4°C, GHB concentrations in the range of 13 μg/mL were even determined. These findings constitute grounds for caution. Even a GHB cut-off level of 5 μg/mL cannot be considered as "absolutely positive" proof of a case of exogenous administration, at least in untreated liquid blood samples in long time storage. However, no significant elevations of GHB were otherwise observed in any of the serum samples independently of storage temperature nor in the whole blood samples that were frozen for storage. CONCLUSIONS: The results suggest that the cut-off for exogenous GHB of 5 μg/mL could be lowered significantly, with the consequence of winning valuable time for the potential victim, but only if serum is collected for GHB determination or if the whole blood sample is frozen immediately after collection and the procedure well documented.     

Raman spectroscopy and microspectrophotometry of reactive dyes on cotton fibres: Analysis and detection limits

A collaborative study on Raman spectroscopy and microspectrophotometry (MSP) was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on different dyed cotton fabrics. The detection limits of the two methods were tested on two cotton sets with a dye concentration ranging from 0.5 to 0.005% (w/w). This survey shows that it is possible to detect the presence of dye in fibres with concentrations below that detectable by the traditional methods of light microscopy and microspectrophotometry (MSP). The MSP detection limit for the dyes used in this study was found to be a concentration of 0.5% (w/w). At this concentration, the fibres appear colourless with light microscopy. Raman spectroscopy clearly shows a higher potential to detect concentrations of dyes as low as 0.05% for the yellow dye RY145 and 0.005% for the blue dye RB221. This detection limit was found to depend both on the chemical composition of the dye itself and on the analytical conditions, particularly the laser wavelength. Furthermore, analysis of binary mixtures of dyes showed that while the minor dye was detected at 1.5% (w/w) (30% of the total dye concentration) using microspectrophotometry, it was detected at a level as low as 0.05% (w/w) (10% of the total dye concentration) using Raman spectroscopy. This work also highlights the importance of a flexible Raman instrument equipped with several lasers at different wavelengths for the analysis of dyed fibres. The operator and the set up of the analytical conditions are also of prime importance in order to obtain high quality spectra. Changing the laser wavelength is important to detect different dyes in a mixture.     

Does Self-Control Influence Maternal Attachment? A Reciprocal Effects Analysis from Early Childhood Through Middle Adolescence

Objectives

The purpose of this study is twofold. First, this study assesses the extent to which self-control and maternal attachment mutually influence one another. Second, it investigates whether this process continues to occur during adolescence. To date, studies of the etiology of self-control have yet to adequately address these issues, despite the fact that a number of theoretical perspectives emphasize the reciprocal nature of the parent-child relationship.

Methods

The current study seeks to shed light on these issues by examining the relationship between self-control and maternal attachment using structural equation modeling for eight waves of data spanning a period of time that encompasses early childhood through middle adolescence.

Results

The results yield two findings bearing on the adequacy of Gottfredson and Hirschi??s model of self-control development. First, measures of self-control and maternal attachment were found to mutually influence one another during childhood. Second, these effects were reduced to nonsignificance during adolescence.

Conclusions

This study finds that self-control emerges during childhood in a complex manner in which it both shapes and is shaped by parental attachment.     

Detecting Feigned PTSD Using the Personality Assessment Inventory

Research generally supports the use of the Personality Assessment Inventory (PAI; Morey 1991) to detect feigned PTSD, although this support has been somewhat mixed. There is also evidence that coaching individuals on the presence of PAI validity indicators may not affect their ability to avoid detection as feigners (Bagby et al. in Journal of Personality Assessment 78:69–86, 2002), although this question has not been specifically addressed with regard to PTSD. Additionally, a new PAI validity indicator, the Negative Distortion Scale (NDS), was developed that may have utility in detecting feigned PTSD, but this has not been tested. The purpose of this study was to further test the operating characteristics of the PAI validity indicators to detect feigned PTSD among naïve and coached respondents and to examine the newly developed NDS for this purpose. Individuals with genuine PTSD were compared to individuals instructed to feign PTSD on PAI validity indicators. Results suggest that: (a) coaching had minimal influence on the ability of the PAI to detect feigned PTSD, (b) the PAI validity indicators all significantly differentiated genuine from feigned PTSD, and (c) the NIM and NDS indicators were particularly effective for detecting feigned PTSD.     

A study of DNA transfers onto plastic packets placed in personal bags

The ability to detect low level DNA brings with it the uncertainty of whether the detected DNA is a result of transfer. To address this uncertainty, a simulation study was conducted in which a mock illicit drug packet was placed into the personal bags of individuals. When the average transit time of the packets was increased from around 2 h to more than 14 h, the percentage of the DNA profiles recovered from the packets which could be attributed to the individuals increased greatly from 5.3% to 48.6%. We found that drug packers who were poor shedders could not be included as contributors to the DNA profiles from the drug packets at all and there was a higher chance that individuals other than themselves could be included as contributors to the DNA profile recovered from drug packets. We also found that it was equally likely that the drug packers who had direct contact with the drug packets and bag owners who did not, could be included as contributors to the DNA profiles recovered from the packets. The results in this study highlight the importance of taking into consideration the transit time of drug packet, the shedder status of the alleged packer and the history of an item, when evaluating DNA evidence in the context of illicit drug activities.     

The Impact of Pro-Government Militias on Human Rights Violations

New data show that between 1982 and 2007, in over 60 countries governments were linked to and cooperated with informal armed groups within their own borders. Given the prevalence of these linkages, we ask how such links between governments and informal armed groups influence the risk of repression. We draw on principal-agent arguments to explore how issues of monitoring and control help understanding of the impact of militias on human rights violations. We argue that such informal agents increase accountability problems for the governments, which is likely to worsen human rights conditions for two reasons. First, it is more difficult for governments to control and to train these militias, and they may have private interests in the use of violence. Second, informal armed groups allow governments to shift responsibility and use repression for strategic benefits while evading accountability. Using a global dataset from 1982 to 2007, we show that pro-government militias increase the risk of repression and that the presence of militias also affects the type of violations that we observe.     

Editors’ introduction: critical terrorism studies: practice,limits and experience

The articles in this special issue are drawn from papers presented at a conference titled Critical Terrorism Studies: Practice, Limits and Experience. The conference was organised by the Critical Studies on Terrorism Working Group of the British International Studies Association (BISA). The event was supported by both a BISA workshop grant and by Loughborough University’s Centre for the Study of International Governance (CSIG) and was held at Loughborough University from 9–10 September 2013. The conference aimed to explore what we know about terrorism and counterterrorism and importantly to ask how we know it. Reflecting the recent “materialist”, “everyday”, “experiential” and “narrative” turns in the fields of International Relations (IR), Geography and Cultural Theory, the event brought together scholars and practitioners to reflect on practices of research and knowledge production in Critical Terrorism Studies and related fields. The articles in this special issue reflect those aims.