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851.
Banknote evidence is often submitted after a suspect has attempted to disguise or remove red dye stain that has been released because of an anti-theft device that activates after banknotes have been unlawfully removed from bank premises. Three chlorinated compounds have been synthesized as forensic chemical standards to indicate bank security dye bleaching as a suspect's intentional method for masking a robbery involving dye pack release on banknotes. A novel, facile synthetic method to provide three chlorinated derivatives of 1-(methylamino)anthraquinone (MAAQ) is presented. The synthetic route involved Ultra Clorox bleach as the chlorine source, iron chloride as the catalyst, and MAAQ as the starting material and resulted in a three-component product mixture. Two mono-chlorinated isomers (2-chloro-1-(methylamino)anthraquinone and 4-chloro-1-(methylamino)anthraquinone) and one di-chlorinated compound (2,4-dichloro-1-(methylamino)anthraquinone) of the MAAQ parent molecule were detected by gas chromatography mass spectrometry (GC-MS), and subsequently isolated by liquid chromatography (LC) with postcolumn fraction collection. Although GC-MS is sensitive enough to detect all of the chlorinated products, it is not definitive enough to identify the structural isomers. Liquid-state nuclear magnetic resonance (NMR) spectroscopy was utilized to elucidate structurally the ortho- and para-mono-chlorinated isomers once enough material was properly isolated. A reaction mechanism involving iron is proposed to explain the presence of chlorinated MAAQ species on stolen banknotes after attempted bleaching.  相似文献   
852.
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.  相似文献   
853.
Violent Sex Offenses: How are They Best Measured from Official Records?   总被引:1,自引:1,他引:0  
In the United States, sexually violent predator (SVP) commitment statutes generally require assessment of an offender's risk of subsequent sexual violence. Current actuarial methods for predicting sexual reoffending were actually designed to predict something else—charges or convictions for offenses deemed sexual based on information obtained from police “rapsheets” alone. This study examined the referral and past offenses of 177 sex offenders. Results showed that police rapsheets (and data based on them) underestimated the number and severity of sexually motivated violent offenses for which sex offenders were actually apprehended. Rapsheet violent offenses seemed a more accurate index of the conduct addressed by SVP legislation than were rapsheet sex offenses. We suggest that, when evaluating sex offenders for SVP status, actuarial instruments designed to predict violent recidivism (as measured by rapsheet violent reoffenses) might be preferable to those designed to predict sexual recidivism (as measured by rapsheet sexual reoffenses).
Marnie E. RiceEmail:
  相似文献   
854.
This study investigated adults’ judgments of the honesty of children's coached true and fabricated mock testimony. Adults saw video clips of children testifying in a mock court about a true or fabricated event in their lives. They were asked to make an assessment of the truthfulness of the testimony, and respond to questions about their perception of children's credibility. Half of the adults saw children testifying after a competence examination, and the other half saw children testifying without a competence examination. Overall, girls were rated as more competent than boys, and their testimony was more likely to be believed. Younger children were more likely to be rated as incompetent than older children. A factor analysis of adults’ responses revealed six factors which significantly predicted adults’ overall assessment of children's credibility, and their evaluations of children's competence to testify. Adults’ detection accuracy was at chance, with the majority of children rated as truthful. Viewing the competency examination and cross-examination did not improve the adults’ detection accuracy. However, seeing the cross-examination made adults’ less likely to believe children's testimony. The implications of these results for the judicial system are discussed.  相似文献   
855.
Drug screening through urinalysis is a widely accepted tool for rapid detection of potential drug use at a relatively low cost. It is, therefore, a potentially useful method for detecting and monitoring drug use in a variety of contexts such as the criminal justice system, pre-employment screening and a variety of treatment centers. This article explores the efficacy of two commercially available drug-screening assays: Online KIMS assay (Roche) and EMIT II assays. First, we evaluate the sensitivity and specificity of two immunoassays. A total of 738 urine samples were collected among adult arrestee populations from Chicago, New Orleans and Seattle through the Arrestee Drug Abuse Monitoring (ADAM) program. Partial samples were split within one laboratory and analyzed by both enzymes multiplied immunoassay technique (EMIT) II and kinetic interaction of microparticle in solution (KIMS) assays for a 10-drug panel (amphetamine, barbiturates, benzodiazepines, marijuana, cocaine, methadone, methaqualone, opiate, phencyclidine and propoxyphene). Gas chromatography-mass spectrometry (GC-MS) was used as a confirmation method for all positives from either EMIT II or KIMS for all experiments. Second, the paper examines whether using different testing laboratories plays a role in the final results. The same experiments were repeated at two different testing locations: one in California and one in London and England. Third, the paper studies whether drug testing results vary between two laboratories when each of them had used their own routine screening method: the Forensic Science Service (FSS) at Birmingham, United Kingdom with KIMS assay and Medscreen Limited at London, United Kingdom with EMIT II. In summary, both EMIT II and KIMS assays generate fairly consistent results. The concordance rate against each of the 10 drugs tested is relatively high (97.4-100%). The discrepancies, in most cases, occurred at drug concentrations near the cut-off levels. There were more discrepant results between two laboratories compared to when specimens were analyzed at the same laboratory using two different assays.  相似文献   
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Utilizing a theoretical perspective (the “social supports model”) increasingly applied by stress researchers in other fields, the present endeavor explores whether social supports operate to shield officers from the stresses emanating from police work To investigate this issue, 91 suburban officers were administered a questionnaire that contained scales measuring four job-related stressors, four types of social supports, and two forms of psychological stress—work and life. With regard to the stressors, the data analysis revealed that feelings of dangerousness were significantly and positively related to both stress scales, while shift change and court problems increased only general lye stress. It was also found that supervisory support mitigates work stress while family support helps to reduce more general psychological discomfort. These latter results rein force the assertion that future research could profit by systematically exploring the circumstances, such as social supports, which enable police to cope effectively with the more stressful features of their work.  相似文献   
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