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471.
We define "dual fingerprint reagents" as chemical formulations that produce with latent fingerprints in one stage impressions that are both colored and fluorescent. Solutions containing ninhydrin and group IIb metal salts appear to be true dual reagents. Application of these formulations to latent fingerprints on paper is as efficient as the two-step process beginning with ninhydrin and followed by treatment with metal salt. In the color mode, fingerprint detectability with the two ninhydrin-metal salt reagents (one with zinc chloride and the other with cadmium chloride) is comparable with that of ninhydrin itself, in spite of the difference in color. The sensitivity is significantly higher in the fluorescence mode. To view the latent impressions the exhibits are treated with ninhydrin-metal salt reagents and observed under white light illumination and under fluorescence conditions. Cooling to liquid nitrogen temperature enhances the fluorescence considerably. In the shorter wavelength domain, ninhydrin-metal salt reagents exhibit higher sensitivity than the recently reported dual reagent, genipin. The latter is advantageous, however, in the longer wavelength domain, on paper items with strong self-fluorescence, such as brown wrapping paper or paper printed with fluorescent ink. Upon reduction of the ninhydrin concentration 10-fold, ninhydrin-metal salt formulations become purely fluorogenic reagents; no color is noticed but the fluorescence is as intense as with concentrated solutions. Working at lower concentrations is an advantage from ecological and economical viewpoints. 相似文献
472.
Irwin JA Edson SM Loreille O Just RS Barritt SM Lee DA Holland TD Parsons TJ Leney MD 《Journal of forensic sciences》2007,52(5):1115-1118
This report describes the genetic identification of James "Earthquake McGoon" McGovern, a WWII fighter ace who perished in Laos while providing supplies to French troops during the French Indochina war. Because reference samples were unavailable for all of the potential casualties, testing of the entire mitochondrial genome, autosomal STRs and Y-chromosomal STRs was performed to increase the genetic information available for analysis. Kinship analyses performed on the evidentiary data and numerous indirect family references for McGovern excluded other possible casualties and definitively established McGovern's identity. This particular case demonstrates the practical utility of novel research technologies and aggressive genetic typing protocols in the identification of aged, degraded remains. 相似文献
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Many scholars argue that the media can influence parliamentarians though the extent of that influence is hotly debated. There is some evidence that the relationship is two way, with politicians taking note of salient media stories but using the media to communicate with their constituents. It is also apparent that, whilst the media may have a role in drawing attention to specific issues, politicians in Kenya do not entirely trust it and thus use a wide range of other sources including government agencies as well as third party sources such as interest groups. This article addresses two gaps in our knowledge―the extent to which parliamentarians in Kenya turn to unofficial sources for information and public opinion, especially interest groups, and the extent to which the media in particular influences parliamentarians in Kenya. The results suggest that parliamentarians in Kenya rely to some extent on both the media and interest groups and that the media is good at raising awareness and stimulating action but that it has only a modest effect on political actions. 相似文献