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Swider C Maguire K Rickenbach M Montgomery M Ducote MJ Marhefka CA 《Journal of forensic sciences》2012,57(4):923-931
Following the September 11, 2001 terrorist attacks, letters containing Bacillus anthracis were distributed through the United States postal system killing five people. A complex forensic investigation commenced to identify the perpetrator of these mailings. A novel liquid chromatography/mass spectrometry protocol for the qualitative detection of trace levels of meglumine and diatrizoate in dried spore preparations of B. anthracis was developed. Meglumine and diatrizoate are components of radiographic imaging products that have been used to purify bacterial spores. Two separate chromatographic assays using multiple mass spectrometric analyses were developed for the detection of meglumine and diatrizoate. The assays achieved limits of detection for meglumine and diatrizoate of 1.00 and 10.0 ng/mL, respectively. Bacillus cereus T strain spores were effectively used as a surrogate for B. anthracis spores during method development and validation. This protocol was successfully applied to limited evidentiary B. anthracis spore material, providing probative information to the investigators. 相似文献
285.
Car key burglary has recently become the focus of empirical investigation as offenders, no longer able to steal vehicles without first obtaining their keys, resort to "burgling" target properties. Research surrounding the modus operandi of these offenses is beginning to emerge; however, little attention has been paid to investigating the characteristics of car key burglary offenders. Challenging the assumption that car key burglary offenses are perpetrated by regular burglars, this study aims to differentiate between offenders. Logistic regression analysis of 110 car key and 110 regular burglary offenders revealed that car key burglars are more likely to have previous vehicle theft convictions and are also more likely to be detected on information supplied to the police than regular burglars. Regular burglars are more likely to have previous shoplifting convictions. It was concluded that car key burglars are a distinct sample of offenders and the implications of these findings are discussed. 相似文献
286.
Gilchrist E Jongekrijg F Harvey L Smith N Barron L 《Forensic science international》2012,219(1-3):50-56
Gunshot residue (GSR) is commonly analysed in forensic casework using either scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) or gas chromatography-mass spectrometry (GC-MS). Relatively little work has been reported on the post-discharge GSR content of non-metallic inorganic or low molecular weight organic anions to distinguish between different ammunition types. The development of an analytical method using suppressed micro-bore anion exchange chromatography (IC) is presented for the analysis of GSR. A hydroxide gradient was optimised for the separation of 19 forensically relevant organic and inorganic anions in <23min and sensitivities of the order of 0.12-3.52ng of anion detected for all species were achieved. Along with an optimised extraction procedure, this method was applied to the analysis of post-ignition residues from three selected ammunition types. By profiling and comparing the anionic content in each ammunition residue, the possibility to distinguish between each type using their anionic profiles and absolute weight is presented. The potential for interference is also discussed with respect to sample types which are typically problematic in the analysis of GSR using SEM-EDX and GC-MS. To the best of our knowledge this represents the first study on the analysis of inorganic anions in GSR using suppressed ion chromatography. 相似文献
287.
Massonnet G Buzzini P Monard F Jochem G Fido L Bell S Stauber M Coyle T Roux C Hemmings J Leijenhorst H Van Zanten Z Wiggins K Smith C Chabli S Sauneuf T Rosengarten A Meile C Ketterer S Blumer A 《Forensic science international》2012,222(1-3):200-207
A collaborative study on Raman spectroscopy and microspectrophotometry (MSP) was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on different dyed cotton fabrics. The detection limits of the two methods were tested on two cotton sets with a dye concentration ranging from 0.5 to 0.005% (w/w). This survey shows that it is possible to detect the presence of dye in fibres with concentrations below that detectable by the traditional methods of light microscopy and microspectrophotometry (MSP). The MSP detection limit for the dyes used in this study was found to be a concentration of 0.5% (w/w). At this concentration, the fibres appear colourless with light microscopy. Raman spectroscopy clearly shows a higher potential to detect concentrations of dyes as low as 0.05% for the yellow dye RY145 and 0.005% for the blue dye RB221. This detection limit was found to depend both on the chemical composition of the dye itself and on the analytical conditions, particularly the laser wavelength. Furthermore, analysis of binary mixtures of dyes showed that while the minor dye was detected at 1.5% (w/w) (30% of the total dye concentration) using microspectrophotometry, it was detected at a level as low as 0.05% (w/w) (10% of the total dye concentration) using Raman spectroscopy. This work also highlights the importance of a flexible Raman instrument equipped with several lasers at different wavelengths for the analysis of dyed fibres. The operator and the set up of the analytical conditions are also of prime importance in order to obtain high quality spectra. Changing the laser wavelength is important to detect different dyes in a mixture. 相似文献
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To understand resilience to climate and environmental changes in fragile and conflict-affected societies is particularly important but equally challenging. In this paper, we first develop a conceptual framework to explore the climate-fragility-conflict and climate-resilience-peace nexus. Second, we discuss approaches to promote pathways from climatic changes to peace. We draw on the relevant literature and International Alert's experience in fragile and conflict-affected societies to stress the key role of resilience. To build resilience, climate, development, peacebuilding, and government actors would have to overcome bureaucratic and institutional barriers and cooperate across thematic and regional silos. 相似文献
290.
Stephen Chaudoin David Thomas Smith Johannes Urpelainen 《The Review of International Organizations》2014,9(4):441-469
Because a significant portion of the American electorate identify themselves as evangelical Christians, the evangelical position on climate policy is important to determining the role the United States could play in global climate cooperation. Do evangelicals oppose all climate policies, or are they particularly opposed to certain types of policies? We argue that American evangelicals oppose climate policy due to their distrust of international cooperation and institutions, which has been a prominent feature of evangelical politics since the beginning of the Cold War. Using data from the 2011 Faith and Global Policy Challenges survey and the 2010 Chicago Council Global View survey, we find support for the theory. Evangelicals are equally likely to support domestic climate policy as other Americans, but they are significantly less likely to support international treaties on climate cooperation. The findings suggest that proponents of climate policy could win more evangelicals to their side by focusing on domestic action, instead of multilateral negotiations or international institutions. 相似文献