Optimization of recovery of human DNA from envelope flaps using DNA IQ™ System for STR genotyping

An optimized protocol based on the DNA IQ™ System has been tested for the extraction of DNA from envelope flaps. DNA is extracted directly without the need for opening and swabbing the flaps. The method is repeatable with <10% R.S.D. (relative standard deviation). The results of a systematic study show that it is an equilibrium extraction, and a small sample volume as well as high lysis buffer content in sample contribute to high extraction efficiency. The extracted DNA requires no further purification steps following its extraction with the DNA IQ™ System. Complete but skewed 15-locus short tandem repeat (STR) profiles, which is typical of degraded of DNA, have been generated from the DNA extracted from 6 to 9 years old casework envelope samples.     

Dealing with allelic dropout when reporting the evidential value in DNA relatedness analysis

A method is suggested that allows the use of loci that have shown allelic dropout in kinship analysis as used for disaster victim identification (DVI) and missing person work (MP). This approach uses an extension of a previously published approach to modelling allelic dropout. This method may salvage some information in cases where allelic dropout is hindering DVI or MP work particularly in reconciliations involving a large number of bodies and pedigrees. It should not replace the pursuit of more complete DNA profiles by the normal rework process for such samples.     

Community juvenile arbitration: An alternative in judicial administration

Congestion in trial courts continues to create a dilemma in judicial administration. In Florida, an effort to address this problem in the juvenile justice system emerged with legislative authorization of community arbitration programs. Implementation came in a joint endeavor of a community and a university to develop a juvenile arbitration program. Assessment of the program in reduction of caseload, cost efficiency, recidivism, reduction of delay prior to hearing, and volunteer participation suggests that community arbitration can be a viable alternative.     

Manners of Death in Drug‐Related Fatalities in Florida

To understand the mortality patterns among drug users and potential risk factors, we evaluated drug‐related deaths reported to the Florida Medical Examiners Commission from 2001 to 2013, by substances, demographics, and manner of death. The annual drug‐related fatalities increased by 57% from 2001 to 2013 (total n = 100,882); 51.8% were accidental, 7.9% homicide, 18.6% natural, and 19.6% suicide. The different manners of death exhibited distinct demographic profiles and drug composition. The gender gap was more prominent in homicide. Age ≥55 years was more closely associated with natural death and suicide. Age <35 years and central nervous system (CNS) stimulants including amphetamines and cocaine showed higher relative risks for accidental death and homicide, whereas CNS depressants including benzodiazepines, carisoprodol, opioids, and zolpidem were more strongly associated with accidental death and/or suicide. The findings aid in identifying populations more vulnerable to drug‐related deaths, developing targeted interventions and thereby improving efficiency of preventive efforts.     

An integrated exploration of factors associated with psychological distress among older prisoners

This paper compares the contributions of socio-demographic, health, mental health, social and environmental factors in explaining variations in psychological distress among older prisoners in two Australian states. One hundred and seventy-three prisoners (aged 50+ ) from 8 Australian prisons were interviewed using the Kessler Psychological Distress (K10) Scale. Three regression analyses were conducted to compare different models of 14 variables significantly associated with psychological distress. Independent variables most prominently associated with variations in psychological distress among older inmates were self-reported levels of social support, self-reported safety and ease of health care access. Difficulties in the built environment and mental health history were significantly explanatory of variations in older prisoner distress in two of the three models. The findings suggest that modifiable situational factors evident in current prison contexts are reasonably explanatory of variations in prisoner distress among older inmates.     

Linking ammonium nitrate-aluminum (AN-AL) post-blast residues to pre-blast explosive materials using isotope ratio and trace elemental analysis for source attribution

Forensic science practitioners are often called upon to attribute crimes using trace evidence, such as explosive remnants, with the ultimate goal of associating a crime with a suspect or suspects in order to prevent further attacks. The explosive charge is an attractive component for attribution in crimes involving explosives as there are limited pathways for acquisition. However, there is currently no capability to link an explosive charge to its source via post-blast trace residues using isotope ratios or trace elements. Here, we sought to determine if pre-blast attribution signatures are preserved after detonation and can be subsequently recovered and detected. A field study was conducted to recover samples of post-blast explosives from controlled detonations of ammonium nitrate-aluminum (AN-Al), which were then analyzed via isotope ratio mass spectrometry (IRMS) and inductively coupled plasma-mass spectrometry (ICP-MS) for quantitation and profiling of isotopes ratio and trace element signatures, respectively. Oxygen and nitrogen isotope ratios from AN-Al yielded some of the most promising results with considerable overlap within one standard deviation of the reference between the spreads of pre- and post-blast data. Trace element results from AN-Al support the findings in the isotope ratio data, with 26 elements detected in both pre- and post-blast samples, and several elements including B, Cd, Cr, Ni, Sn, V, and Zn showing considerable overlap. These preliminary results provide a proof-of-concept for the development of forensic examinations that can attribute signatures from post-blast debris to signatures in pre-blast explosive materials for use in future investigations.     

Global perspectives on scientists’ roles in legislative policymaking

Policy Sciences - The question of how scientists should engage in policymaking has spurred both pragmatic and philosophical debates for decades. Scant empirical research addressing how experts...