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961.
962.
Egan JM Rickenbach M Mooney KE Palenik CS Golombeck R Mueller KT 《Journal of forensic sciences》2006,51(6):1276-1283
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
963.
964.
In forensic image processing, it is often important to be able to separate a feature from an interfering background or foreground, or to demonstrate colors within an image to be different from each other. In this study, a color deconvolution algorithm that could accomplish this task is described, and it is applied to color separation problems in document and fingerprint examination. Subtle color differences (sometimes invisible to the naked eye) are found to be sufficient, which is demonstrated successfully for several cases where color differences were shown to exist, or where colors were removed from the foreground or background. The software is available for free in the form of an Adobe Photoshop-compatible plug-in. 相似文献
965.
The United States prison population is becoming more diverse and comprised of increasingly more violent inmates. Although race has been cited as a risk factor for inmate violence, most prior research had narrowly investigated White/Black differences in inmate misconduct. Using a sample of 1,005 inmates from the southwestern U.S., the current study explored racial, ethnic, and citizenship correlates among male and female prisoners. Negative binomial regression models indicated that net of controls, Hispanics and Native Americans were the most violent male prisoners, while African Americans and Native Americans were the most violent female inmates. The current study was admittedly modest in scope; however, the findings were couched within a broader, imperative sociological framework that lamented the increasing interplay between communities and prison and the role of prison as a social institution. 相似文献
966.
T. E. Bosch 《Communicatio》2013,39(1):88-100
Abstract Kwaito can be described as the new music of the new South Africa. Since its emergence over a decade ago, kwaito still blasts from minibus taxis, on the new urban commercial stations formed after media liberalisation, and on street corners from Cape Town to Johannesburg. Kwaito is young, vibrant and decidedly black. This is hardly surprising in a context where music, like everything else, is a highly racialised terrain. This article describes the emergence of kwaito, and explores community radio station, Bush Radio's, broadcasts of kwaito music, looking at how these broadcasts create a sense of community. First, kwaito's emergence within the context of South Africa's mainstream cultural industries is articulated. Then kwaito music is explored as a signifier of black identity. This article is located within a cultural studies framework, which approaches musical genres as cultural texts capable of generating multiple meanings (Grossberg, 1993). 相似文献
967.
T.G. Otte 《Diplomacy & Statecraft》2013,24(1):271-290
Niall Ferguson, The Pity of War (London: Allen Lane/The Penguin Press, 1998). xlv + 623 pp., £18.99 (hb), ISBN 0–713–99246–8. Niall Ferguson (ed.), Virtual History: Alternatives and Counterfactuals (London: Picador, 1997). 548 pp., £20 (hb), ISBN 0–330–35132‐X. 相似文献
968.
969.
The incidence of drug and chemical related deaths was studied over a six-year period in the State of Maryland. Deaths were classified into the following categories: alcohol, carbon monoxide (CO), single drugs, multiple drugs, and narcotism. The last three categories were further subdivided as to the specific drugs or chemicals involved. Over the six-year period the number of alcohol and CO deaths remained steady, the number of barbiturate and propoxyphene deaths declined, while the number of tricyclic antidepressant drug deaths increased. 相似文献
970.
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