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991.
This study investigates the enhancement of footwear impressions prepared with soils from different locations on a variety of fabric surfaces with different morphology. Preliminary experiments using seventeen techniques were carried out and the best responding reagents were evaluated further. Results indicated that the soils investigated (a cross-section of soils from Scotland) are more likely to respond to reagents that target iron ions rather than calcium, aluminium or phosphorus ions. Furthermore, the concentration of iron and soil pH did not appear to have an effect on the performance of the enhancement techniques. For the techniques tested, colour enhancement was observed on all light coloured substrates while enhancement on dark coloured fabrics, denim and leatherette was limited due to poor contrast with the background. Of the chemical enhancement reagents tested, 2,2'-dipyridil was a suitable replacement for the more common enhancement technique using potassium thiocyanate. The main advantages are the use of less toxic and flammable solvents and improved clarity and sharpness of the enhanced impression. The surface morphology of the fabrics did not have a significant effect on the enhancement ability of the reagents apart from a slight tendency for diffusion to occur on less porous fabrics such as polyester and nylon/lycra blends. 相似文献
992.
Leyton V Sinagawa DM Oliveira KC Schmitz W Andreuccetti G De Martinis BS Yonamine M Munoz DR 《Forensic science international》2012,218(1-3):25-27
Lysergic acid diethylamide (LSD) is a potent hallucinogen, active at very low dosage and its determination in body fluids in a forensic context may present some difficulties, even more so in hair. A dedicated liquid chromatography-electrospray-tandem mass spectrometry (LC-ES-MS/MS) assay in hair was used to document the case of a 24-year-old man found dead after a party. Briefly, after a decontamination step, a 50mg sample of the victim's pubic hair was cut into small pieces (<1mm length), and incubated overnight in 3mL of phosphate buffer pH 5 at room temperature. After a liquid-liquid extraction (dichloromethane/ether), the extract was analyzed using a LC-ES-MS/MS method exhibiting a limit of quantification of 0.5pg/mg for LSD. A LSD concentration of 0.66pg/mg of pubic hair was observed. However, this result remains difficult to interpret owing to the concomitant LSD presence in the victim's post mortem blood and urine, the lack of previously reported LSD concentrations in hair, and the absence of data about LSD incorporation and stability in pubic hair. 相似文献
993.
C. Haas E. HansonM.J. Anjos W. BärR. Banemann A. BertiE. Borges C. BouakazeA. Carracedo M. CarvalhoV. Castella A. ChomaG. De Cock M. DötschP. Hoff-Olsen P. JohansenF. Kohlmeier P.A. LindenberghB. Ludes O. MaroñasD. Moore M.-L. MorerodN. Morling H. NiederstätterF. Noel W. ParsonG. Patel C. PopielarzE. Salata P.M. SchneiderT. Sijen B. Svie?enaM. Turanská L. ZatkalíkováJ. Ballantyne 《Forensic Science International: Genetics Supplement Series》2012,6(1):70-80
A second collaborative exercise on RNA/DNA co-analysis for body fluid identification and STR profiling was organized by the European DNA Profiling Group (EDNAP). Six human blood stains, two blood dilution series (5-0.001 μl blood) and, optionally, bona fide or mock casework samples of human or non-human origin were analyzed by the participating laboratories using a RNA/DNA co-extraction or solely RNA extraction method. Two novel mRNA multiplexes were used for the identification of blood: a highly sensitive duplex (HBA, HBB) and a moderately sensitive pentaplex (ALAS2, CD3G, ANK1, SPTB and PBGD). The laboratories used different chemistries and instrumentation. All of the 18 participating laboratories were able to successfully isolate and detect mRNA in dried blood stains. Thirteen laboratories simultaneously extracted RNA and DNA from individual stains and were able to utilize mRNA profiling to confirm the presence of blood and to obtain autosomal STR profiles from the blood stain donors. The positive identification of blood and good quality DNA profiles were also obtained from old and compromised casework samples. The method proved to be reproducible and sensitive using different analysis strategies. The results of this collaborative exercise involving a RNA/DNA co-extraction strategy support the potential use of an mRNA based system for the identification of blood in forensic casework that is compatible with current DNA analysis methodology. 相似文献
994.
995.
Scholars have spent a great deal of effort examining the effects of negative advertising on citizens’ perceptions of candidates. Much of this work has used experimental designs and has produced mixed findings supporting one of two competing theories. First, negative ads may harm candidates who sponsor them because citizens tend to dislike negativity. Second, negativity may drive down citizens’ support for the targeted candidate because the attacks give people reasons to reject the target. We argue that the mixed findings produced by prior research may be driven by a disregard for campaign dynamics. We present a critical test of these two theories using data drawn from 80 statewide elections—37 gubernatorial and 43 U.S. Senate contests—from three election years and public opinion polling collected during the last 12 weeks of each campaign. We find that a candidate’s support declines as her advertising strategy includes a higher proportion of negative ads relative to her opponent and that this process unfolds slowly over the course of the campaign. 相似文献
996.
De Leon Petta Gomes da Costa 《Astropolitics》2016,14(1):90-98
With the Obama Administration’s foreign policy pivot to Asia, the Chinese government is concerned about the possibility of new challenges in their foreign policy sphere of influence. Since the 1990s, many political and military analysts have explored the eventual rivalry between these two states. However, events in the Middle East preoccupy U.S. attention, leaving China moderately free in Southeast Asia, though it is uncertain for how long this will persist and if the United States will reallocate its attention to contain China. In this case, the Chinese government will need to develop countermeasures to sustain its geopolitical interests. There are two focuses in this analysis: (1) the Chinese geopolitical naval situation, exploring the problems in the geosphere surrounding China and the eventual competition with other regional powers and the United States in East Asia; and (2) the potential for space program cooperation with Russia and Brazil, which, in turn, dramatically changes the balance of power in outer space through positive aspects of Russian technical capabilities and strategic Brazilian geographic (Alcântara launch site). 相似文献
997.
Kevin Quigley Colin Macdonald John Quigley 《Canadian public administration. Administration publique du Canada》2016,59(2):267-288
This article examines the claim that the media exaggerated the threat of H1N1, prompting an immediate demand for limited vaccine. We compare The Australian's and the Daily Telegraph's coverage of H1N1 with that of The Globe and Mail, which was comparatively critical of government performance. The events of October 2009 underscore the difficulty and importance of responding to media coverage of “uncertain risks” (Renn 2008 ), risks for which there is a lack of scientific basis for decision making and potentially generate anxious public responses. 相似文献
998.
Françoise De Bel-Air 《The international spectator : a quarterly journal of the Istituto affari internazionali》2018,53(2):52-73
Migration from South and East Mediterranean (SEM) countries has been considered a growing security threat in the EU and Gulf states following the 9/11 attacks and the Arab uprisings. Since 2011, the economic slowdown, regime changes and socio-political instability have spurred growing migration pressure from SEM countries. However, the securitisation of migration of young citizens from these countries in the EU and the Gulf states is manifested in the drastic limitation of migrants’ inflows, and in the selection of prospective migrants on demographic, socio-economic and political grounds. Today’s ‘governmentality’ of youth migration from SEM countries poses ethical and development-related issues. 相似文献
999.
1000.