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181.
182.
The purpose of this study was to determine whether criminal thinking underpins peer influence and selection. It was predicted that proactive criminal thinking would mediate the peer influence effect (peers?→?offending) and reactive criminal thinking would mediate the peer selection effect (offending?→?peers). Participants were 1,170 male delinquent youth from the Pathways to Desistance study. The Moral Disengagement scale (proactive criminal thinking) and Peer Delinquent Behavior scale (peer delinquency) were cross-lagged to predict criminal offending, and the Weinberger Impulse Control scale (reactive criminal thinking) and criminal offending were cross-lagged to predict peer delinquency. Consistent with predictions, proactive but not reactive criminal thinking successfully mediated the peer?→?offending relationship and reactive but not proactive criminal thinking successfully mediated the offending?→?peer relationship. Whereas delinquent peer associations appear to promote proactive criminal thinking and peer influence, early criminal offending appears to promote reactive criminal thinking and peer selection.  相似文献   
183.
Young Cambodians are often the victims of human rights abuses due to their interactions with the criminal justice system. This paper is based on the outcomes of a 6-month research project which gained the perceptions of young male Cambodians who reported that violence within the criminal justice system is normalised and perpetrated by police and prison authorities. The research documented the physical and psychological effects of institutional violence encountered by young people such as problems in reintegrating back to their families and communities. The paper concludes with a number of suggestions regarding the introduction of a juvenile justice system, increased training of police and the introduction of human rights as part of the national school curriculum.  相似文献   
184.
The Middle East is one of the world regions that has frequently suffered from armed conflicts that resulted in mass burials. However, the detection of clandestine graves in such an arid environment by deploying remote sensing payload on unmanned aerial vehicles (UAVs) has received little attention. The present study used a UAV equipped with a thermal sensor aimed at narrowing down the search area of possible gravesites in the arid climate of Kuwait. The enclosed research area, which includes both control and experimental mass graves, was imaged for 18 months. The variation in topsoil temperature and soil moisture between the graves and their surroundings was evaluated. The results of the analysis demonstrated the effectiveness of thermal imaging techniques in detecting heat produced from buried sheep carcasses and detecting the change in grave soil moisture for our research environment for 7 and 10 months, respectively. The buried animals significantly influenced the topsoil temperature (p = 0.044), while the height from which the images were captured had an insignificant effect on the measured temperature within the range tested (p = 0.985). Furthermore, there was a negative correlation (−0.359) between grave temperature and the calculated soil moisture. The results from these cost- and time-effective search methods presented in this study confirm their potential for the detection of burial sites in an arid environment.  相似文献   
185.
Fentanyl, fentanyl analogs, and other novel synthetic opioids (NSO), including nitazene analogs, prevail in forensic toxicology casework. Analytical methods for identifying these drugs in biological specimens need to be robust, sensitive, and specific. Isomers, new analogs, and slight differences in structural modifications necessitate the use of high-resolution mass spectrometry (HRMS), especially as a non-targeted screening method designed to detect newly emerging drugs. Traditional forensic toxicology workflows, such as immunoassay and gas chromatography mass spectrometry (GC–MS), are generally not sensitive enough for detection of NSOs due to observed low (sub-μg/L) concentrations. For this review, the authors tabulated, reviewed, and summarized analytical methods from 2010–2022 for screening and quantification of fentanyl analogs and other NSOs in biological specimens using a variety of different instruments and sample preparation approaches. Limits of detection or quantification for 105 methods were included and compared to published standards and guidelines for suggested scope and sensitivity in forensic toxicology casework. Methods were summarized by instrument for screening and quantitative methods for fentanyl analogs and for nitazenes and other NSO. Toxicological testing for fentanyl analogs and NSOs is increasingly and most commonly being conducted using a variety of liquid chromatography mass spectrometry (LC–MS)-based techniques. Most of the recent analytical methods reviewed exhibited limits of detection well below 1 μg/L to detect low concentrations of increasingly potent drugs. In addition, it was observed that most newly developed methods are now using smaller sample volumes which is achievable due to the sensitivity increase gained by new technology and new instrumentation.  相似文献   
186.
Forensic science professionals are routinely exposed to potentially traumatizing evidence. This study aimed to estimate the prevalence of occupational posttraumatic stress disorder (PTSD) among forensic science professionals, identify job-related correlates of PTSD symptoms, and examine the role of social support in mitigating PTSD symptomology. In response to recruitment through the American Academy of Forensic Sciences, the American Society of Crime Laboratory Directors, and Evidence Technology Magazine, 449 forensic science professionals participated in the current study. Results found that 73.5% (n = 330) of the overall sample experienced at least one work-related traumatic event consistent with meeting Criterion A for PTSD, and these rates were higher for field-based respondents (n = 203, 87.9%). The prevalence of past-month provisional PTSD was 21.6% for the full sample. Disaggregated PTSD rates were 29.0% and 14.5% for field-based and non-field-based respondents, respectively. These rates were 6- to 8-fold higher than the past-year prevalence of PTSD in the general US population, estimated to be 3.5%, and were found to be at least as high as those observed in prior epidemiological research with non-treatment seeking members of the US military deployed to war zones in Iraq and Afghanistan. Results further showed that social support was protective against PTSD symptomology. The high rates of occupational exposure to trauma and consequent PTSD symptomology observed in this large sample of forensic science professionals highlight the under-acknowledged psychological risks of these occupations and the need for enhanced attention to mental health resources for these professionals.  相似文献   
187.
In the absence of surface indications of burial sites, law enforcement or humanitarian organizations are faced with the difficult task of focusing large-scale ground searches to a manageable excavation area. A geoforensic-based survey may exclude parts of the landscape for reasons such as diggability or viewshed analysis but leave areas still too large for invasive exploration. This work examines how drone-based remote sensing, geophysics, and search dogs may be combined to narrow such searches. Here, we ask the reader to consider two examples where forensic geomorphology and land use provided a range of possible burial locations. Following this is a multi-proxy approach to similar dilemma, with a search-to-scene case study using remote sensing (drone photography), geophysics, ground probes, and search dogs. This approach is not presented as a definitive guide, but serves as an example of the conjunctive use of well-studied methods to approach a common problem in geoforensics.  相似文献   
188.
A fatal case of 1,4-butanediol (1,4-BD) oral ingestion is reported here, in which a 51-year-old man was found dead in his bed. According to the police report, the deceased was a known drug user. A glass bottle labeled (and later confirmed to be) “Butandiol 1,4” (1,4-BD) was found in the kitchen. Furthermore, the deceased's friend stated that he consumed 1,4-BD on a regular basis. The autopsy and histological examination of postmortem parenchymatous organ specimens did not revealed a clear cause of death. Chemical-toxicological investigations revealed gammahydroxybutyrat (GHB) in body fluids and tissues in the following quantities: femoral blood 390 mg/L, heart blood 420 mg/L, cerebrospinal fluid 420 mg/L, vitreous humor 640 mg/L, urine 1600 mg/L, and head hair 26.7 ng/mg. In addition, 1,4-BD was qualitatively detected in the head hair, urine, stomach contents, and the bottle. No other substances, including alcohol, were detected at pharmacologically relevant concentrations. 1,4-BD is known as precursor substance that is converted in vivo into GHB. In the synoptic assessment of toxicological findings, the police investigations and having excluded other causes of death, a lethal GHB-intoxication following ingestion of 1,4-BD, can be assumed in this case. Fatal intoxications with 1,4-BD have seldom been reported due to a very rapid conversion to GHB and, among other things, non-specific symptoms after ingestion. This case report aims to give an overview to the published of fatal 1,4-BD-intoxications and to discuss the problems associated with detection of 1,4-BD in (postmortem) specimens.  相似文献   
189.
Aminoindanes are a class of novel psychoactive substances (NPSs) that have become more prevalent over the past decade. GC–MS is often utilized for identifying seized drugs and is well regarded for its ability to separate mixtures. However, certain aminoindanes have similar mass spectral data and require specific gas chromatographic stationary phases for separation. Derivatization is an alternative method that can be applied to GC–MS to enhance chromatographic results, providing more selective analysis in seized-drug identification. This study investigates derivatization techniques to provide options for forensic science laboratories in accurately identifying aminoindanes. Three derivatization reagents, N-methyl-bis(trifluoroacetamide) (MBTFA), heptafluorobutyric anhydride (HFBA), and ethyl chloroformate (ECF) were evaluated for the analysis of eight aminoindanes by GC–MS using two common gas chromatographic stationary phases, Rxi®-5Sil MS and Rxi®-1Sil MS. All three derivatization methods successfully isolated eight aminoindanes, including the isomers 4,5-methylenedioxy-2-aminoindane (4,5-MDAI), and 5,6-methylenedioxy-2-aminoindane (5,6-MDAI) that could not be differentiated prior to derivatization. Reduced peak tailing and increased abundance were observed after derivatization for all the compounds, and mass spectra of the derivatives contained individualizing fragment ions that allowed for further characterization of the aminoindanes. This excluded 4,5-MDAI and 5,6-MDAI as they shared the same characteristic ions and were only distinguishable by their retention times. All three derivatization techniques used in this study allow for successful characterization of the aminoindanes and give forensic science laboratories flexibility in their analysis approach when they encounter these compounds.  相似文献   
190.
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.  相似文献   
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