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Deep Puzzles     
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There is increasing evidence that some individuals actively seek to bring about their own deaths by provoking armed police officers to shoot them. The current paper examines 22 police shooting incidents, nine fatal, between 1998 and 2001, to assess the likelihood of suicidal motivation in each of these cases. All 22 individuals shot were male, 18 were white, three black and one Asian and ages ranged from 18 to 51. Around half of the shootings examined have some evidence indicating a suicidal motive in those shot, with further indications of irrational behaviour in a number of the other cases. This has clear implications for the choice of police strategy in responding to such incidents and an imperative to develop ‘less lethal’ options to minimise the risk to such vulnerable populations.  相似文献   
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Conventional Gas Chromatography‐Mass Spectrometry (GC‐MS) methods for the analysis of ignitable liquids (ILs) are usually time‐consuming, and the data produced are difficult to interpret. A fast IL screening method using direct analysis in real time mass spectrometry (DART‐MS) is proposed in this study. GC‐MS, QuickStrip DART‐MS, and thermal desorption DART‐MS methods were used to analyze neat ILs and thermal desorption DART‐MS without extraction was used to analyze ILs on five substrates (e.g., carpet, wood, cloth, sand, and paper). Compared to GC‐MS, DART‐MS methods generated different spectral profiles for neat ILs with more peaks in the higher mass range and also provided better detection of less volatile compounds. ILs on substrates were successfully classified (98 ± 1%) using partial least squares discriminant analysis (PLS‐DA) models based on thermal desorption DART‐MS data. This study shows that DART‐MS has great potential for the high‐throughput screening of ILs on substrates.  相似文献   
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This paper describes the process of change in attitudes of male social workers’ towards themselves and towards their clients who are male perpetrators of partner violence (PV). The process reveals a reconstruction of the therapist’s beliefs concerning key elements in their work related being, such as masculinity, aggression, perception of their clients and their own male identities. The sample includes 15 male social workers that worked with battering men in social services. Data collection was performed through semi-structured interviews. The therapists’ process of questioning the popular and accepted demonization of violent men clarifies what differentiates them from their clients, but also opens an authentic pathway to examining similarities they share as men, without the need to be politically correct or to conform. The implications for practitioners working in batterers’ intervention programs are addressed.  相似文献   
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Connection of a perpetrator to a sexual assault is best performed through the confirmed presence of semen, thereby proving sexual contact. Evidentiary items can include sanitary napkins or diapers containing superabsorbent polymers (SAPs), complicating spermatozoa visualization and DNA analysis. In this report, we evaluated the impact of SAPS on the current forensic DNA workflow, developing an efficient centrifugal protocol for separating spermatozoa from SAP material. The optimized filtration method was compared to common practices of excising the top layer only, resulting in significantly higher sperm yields when a core sample of the substrate was taken. Direct isolation of the SAP‐containing materials without filtering resulted in 20% sample failure; additionally, SAP material was observed in the final eluted DNA samples, causing physical interference. Thus, use of the described centrifugal‐filtering method is a simple preliminary step that improves spermatozoa visualization and enables more consistent DNA yields, while also avoiding SAP interference.  相似文献   
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Gunshot Residue (GSR) produced by the discharge of a firearm often provides very useful information in criminal investigations in cases involving the use of firearms. Scanning Electron Microscopy equipped with an Energy Dispersive X-ray Spectrometer (SEM-EDS) is typically used worldwide to visualize micrometric particles constituting GSR and to analyse their elemental composition. The 2017 ASTM Standard guide for gunshot residue analysis by scanning electron microscopy/energy dispersive X-ray spectroscopy specifies that “Particles classified as characteristic of GSR will have one of the following elemental compositions: Lead, antimony, barium; Lead, barium, calcium, silicon, tin”. For the first time, the presence of an additional element, such as Sn, plays a key role in ASTM particle classification. It is known that some ammunitions, used for pistols, revolvers and rifles, contain tin foil discs for sealing the primer mixture into the cup, resulting in GSR particles containing Sn. The authors faced some cases in which Sn was unexpectedly found in GSR particles from a 0.22 Long Rifle derringer and from some 12 gauge shotguns. No tin foil discs are used in rimfire ammunitions and there is no published evidence of tin foil discs in shotshell ammunitions. Following a “case by case” approach, experimental research has been carried out to explain how Sn can be present in GSR particles when the last discharged cartridge also does not contain any Sn either in components and in the explosive charges.Moreover, the use of Particle Induced X-ray Emission (PIXE) showed the capability to overcome overlap ambiguity of Sb and Sn peaks in the X-ray spectra, being a possible key issue in real shooting cases if Sn quantities are below the lower limit of SEM detection, especially when Sb is also present.  相似文献   
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