Characterization of the N+3 stutter product in the trinucleotide repeat locus DYS392

Stutter products generated during DNA amplification by the polymerase chain reaction (PCR) may complicate mixture interpretation. The PCR amplification of the DYS392 locus typically results in three distinct detectable PCR products: the true allele product (N), a stutter product three bases smaller (N-3), and a reproducible low-level product, three bases larger (N+3). Sequence analysis of the N+3 product demonstrated that its sequence is one TAT repeat longer than the true allele product. Our experiments demonstrated that the quantity of both N-3 and N+3 stutter increased as the allele number increased. The percent stutter also increased as the magnesium concentration was increased in the reaction, as well as when the amount of input DNA was decreased. As both stutter products behave in a similar and reproducible fashion, the same rules that apply to the interpretation of N-3 stutter products in short tandem repeat analysis, can be applied to N+3 stutters. The characterization of the DYS392 N+3 product is the first detailed published study of a stutter product larger than the true allele.     

Microbial metagenome profiling using amplicon length heterogeneity-polymerase chain reaction proves more effective than elemental analysis in discriminating soil specimens

The combination of soil's ubiquity and its intrinsic abiotic and biotic information can contribute greatly to the forensic field. Although there are physical and chemical characterization methods of soil comparison for forensic purposes, these require a level of expertise not always encountered in crime laboratories. We hypothesized that soil microbial community profiling could be used to discriminate between soil types by providing biological fingerprints that confer uniqueness. Three of the six Miami-Dade soil types were randomly selected and sampled. We compared the microbial metagenome profiles generated using amplicon length heterogeneity-polymerase chain reaction analysis of the 16S rRNA genes with inductively coupled plasma optical emission spectroscopy analysis of 13 elements (Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Si, and Zn) that are commonly encountered in soils. Bray-Curtis similarity index and analysis of similarity were performed on all data to establish differences within sites, among sites, and across two seasons. These data matrices were used to group samples that shared similar community patterns using nonmetric multidimensional scaling analysis. We concluded that while chemical characterization could provide some differentiation between soils, microbial metagenome profiling was better able to discriminate between the soil types and had a high degree of reproducibility, therefore proving to be a potential tool for forensic soil comparisons.     

Amino acid alanine reactivity with the fingerprint reagent ninhydrin. A detailed ab initio computational study

Ninhydrin is one of the most widely used reagents for chemical development of fingerprints on porous surfaces. The detection is based on the reaction of ninhydrin with a monoacidic component of the fingerprint to form an intensively colored compound named Ruhemann's Purple. A computational study of the mechanisms and reaction energetics of the formation of Ruhemann's Purple from ninhydrin and alanine is presented. Such a study is significant from a forensic science point of view because of the strong interest in the forensic chemistry and law enforcement communities in developing alternatives to the current generation of ninhydrin like chemicals for the detection and development of latent fingerprints. Information about the mechanism of reaction between ninhydrin and amino acids can ultimately help to design compounds with stronger chromo-fluorogenic properties in aid of detecting fingerprints at crime scenes. The three most accepted mechanisms of formation have been considered using ab initio quantum mechanical calculations. At relatively high temperature ( approximately 100 degrees C) all three mechanisms are energetically feasible. However since it is recommended that forensic analyses be performed at room temperature, a revised mechanism is proposed for the formation of Ruhemann's Purple under this condition.     

Prevalence of mental disorders and deliberate self-harm in Greek male prisoners

The aim of this survey was to determine the prevalence of current and lifetime mental disorder and deliberate self-harm among male prisoners in Greece. The subjects were 80 randomly selected remanded and sentenced prisoners in a Greek prison. They were assessed for mental disorder including suicidality and substance misuse using the Mini International Neuropsychiatric Interview (MINI). We also collected information regarding contact with psychiatric services, previous deliberate self-harm as well as physical health and conducted a brief assessment of their intellectual functioning. Mental disorder was diagnosed in 63 (78.7%) prisoners. The main diagnoses were: anxiety disorder, 30 (37.5%); major depression, 22 (27.5%); antisocial personality disorder, 30 (37.5%); alcohol dependence, 21 (26.3%) and opiate dependence 22 (27.5%) and schizophrenic or bipolar disorder 9 (11.2%). Deliberate self-harm prior to and during imprisonment was reported by 15% and 2.5% of prisoners, respectively, and 12 prisoners (15%) had IQ below 75. This survey identified a significant level of need for specialist mental health services in prison. Further studies are required to assess the specific needs of those patients who are too unwell to remain in prison, the need for specific treatments for substance misuse and improved assessment/treatment of common psychiatric disorders.     

Prisons in transition

The role of the prison has changed, in some ways dramatically, over the last two decades. The prison population has grown and its composition has altered. There has been an increase in the depth and weight of imprisonment, and a hardening of its emotional tone. Prisoners' voices have been silenced, outcomes have deteriorated, and yet public presentation of the prison has improved. Power has shifted upwards, as senior managers have an unprecedented grip on establishments and their 'performance'. There are new fantasies about, and constructions of, the prison's role, with little evidence to support such public and political dreams. Such sleights of hand are only possible without knowledge of the prison's interior life. Punitive prisons which treat prisoners, and possibly prison staff, unfairly and with little or no respect add to human suffering and do not address either the problem of crime or the problem of public fear.     

Prisoners’ Positive Illusions of Their Post-Release Success

Prisoners' forecasts of post-release success may have implications for how they respond to imprisonment, release, and parole decisions. We examined sentenced US and UK prisoners' forecasts of recidivism, and how well UK prisoners believed they would fare compared to the average other prisoner. In both samples, forecasts of recidivism were unrealistically optimistic when compared to official statistics on recidivism. UK prisoners also demonstrated a self-enhancement bias by forecasting that they were less likely to re-offend than other prisoners. Prisoners' forecasts of recidivism were predicted by only a few of the pre-prison, in-prison, and post-prison factors that have been shown to be associated with actual recidivism. We discuss the implications of these findings and propose avenues for future research.     

Strategic Use of Evidence During Police Interviews: When Training to Detect Deception Works

Research on deception detection in legal contexts has neglected the question of how the use of evidence can affect deception detection accuracy. In this study, police trainees (N=82) either were or were not trained in strategically using the evidence when interviewing lying or truth telling mock suspects (N=82). The trainees’ strategies as well as liars’ and truth tellers’ counter-strategies were analyzed. Trained interviewers applied different strategies than did untrained. As a consequence of this, liars interviewed by trained interviewers were more inconsistent with the evidence compared to liars interviewed by untrained interviewers. Trained interviewers created and utilized the statement-evidence consistency cue, and obtained a considerably higher deception detection accuracy rate (85.4%) than untrained interviewers (56.1%).     

Simultaneous analyses of cocaine, cocaethylene, and their possible metabolic and pyrolytic products

A method was developed for simultaneously analyzing cocaine (COC), benzoylecgonine (BZE), norbenzoylecgonine (BNE), norcocaine (NCOC), ecgonine (ECG), ecgonine methyl ester (EME), m-hydroxybenzoylecgonine (HBZE), anhydroecgonine methyl ester (AEME), cocaethylene (CE), norcocaethylene (NCE), and ecgonine ethyl ester (EEE) in blood, urine, and muscle. Available deuterated analogs of these analytes were used as internal standards. Proteins from blood and muscle homogenate were precipitated with cold acetonitrile. After the removal of acetonitrile by evaporation, the supernatants and urine were subjected to solid-phase extraction. The eluted analytes were converted to their hydrochloride salts and derivatized with pentafluoropropionic anhydride and 2,2,3,3,3-pentafluoro-1-propanol. The derivatized products were analyzed by a gas chromatograph (GC)/mass spectrometer by selected ion monitoring. The limit of detection (LOD) for COC, BZE, NCOC, EME, CE, NCE, and EEE was 2ng/ml, while the LODs for BNE, ECG, HBZE, and AEME were 25, 640, 50, and 13 ng/ml, respectively. This method was successfully applied in analyzing 13 case samples from aviation accident pilot fatalities and motor vehicle operators. AEME concentrations found in the 13 samples were consistent with those produced solely by the GC inlet pyrolysis of COC controls in blood. Anhydroecgonine cannot be used as a marker for the abuse of COC by smoking because it is also pyrolytically produced from COC metabolites on the GC inlet. The developed method can be effectively adopted for analyzing COC and related compounds in urine, blood, and muscle by a single extraction with increased sensitivity through formation of hydrochloride salts and using a one-step derivatization.     

Four X-chromosomal STRs and their allele frequencies in a Chinese population

X-chromosomal markers are particularly useful for solving complex problems relating to kinship and deficiency paternity analysis. In the present study, population genetics data of four X-chromosomal short tandem repeats (STRs) DXS8378, HPRTB, DXS7423 and DXS7132 were obtained by analyzing 500 unrelated Chinese individuals (250 males and 250 females). Population genetics data obtained from the Chinese were compared with those of the Asian and European population. Mutations in X-chromosomal markers were analyzed based on a total of 61 proven father-child and 45 proven mother-child pairs.