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Doping control laboratories accredited by the World Anti-Doping Agency (WADA) require criteria that allow endogenous steroids to be distinguished from their synthetic analogues in urine. Methodology based on "looking outside the metabolic box" was used in this study to identify diagnostic urinary markers of 4-androstenediol (4-ADIOL) administration. Androst-2,4-diene-17-one and androst-3,5-diene-17-one are proposed to be formed in urine from acid-catalyzed hydrolysis of 4-ADIOL sulfoconjugate, a major phase II metabolic product of 4-ADIOL. The presence of these markers in the routine gas chromatography-mass spectrometry (GC-MS) steroid screen was suitable to identify samples requiring confirmation by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) - to measure the carbon isotope ratio (δ(13)C) of the androstdiene markers and confirm their likely synthetic origin based on depleted (13)C content. 相似文献
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This paper takes the influential ??direct democracy makes people happy??-research as a starting point and asks whether direct democracy impacts individual satisfaction. Unlike former studies we distinguish two aspects of individual satisfaction, namely satisfaction with life (??happiness??) and with how democracy works. Based on multilevel analysis of the 26 Swiss cantons we show that the theoretical assumption on which the happiness hypothesis is based has to be questioned, as there is very little evidence for a robust relationship between satisfaction with democracy and life satisfaction. Furthermore, we do not find a substantive positive effect of direct democracy on happiness. However, with respect to satisfaction with democracy, our analysis shows some evidence for a procedural effect of direct democracy, i.e. positive effects related to using direct democratic rights, rather than these rights per se. 相似文献
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De Grazia A Mikhael M Stojanovska N Reedy B Shimmon R Tahtouh M 《Forensic science international》2012,216(1-3):189-197
In 1979, Miller and Patel showed that a solution containing two diacetylene monomers, 2,4-hexadiyne-1,6-bis(phenylurethane) (HDDPU) and 2,4-hexadiyne-1,6-bis(p-chlorophenylurethane) (HDDCPU) could be used to develop latent fingermarks on a non-porous surface. In the current work, the same mixture (HDDPU:HDDCPU=10:1, in acetone solution) was used to develop fingermarks on a wide variety of surfaces, both non-porous and porous, including paper. An airbrush system was optimized for the application of the reagent solution. Once the solution evaporates on a surface, the monomers co-crystallize in different ways, depending upon a number of factors, including the surface residue. "Active" co-crystallization leads (with heat or radiation) to the formation of purple polymer, while "inactive" crystallization results in a non-polymerizable white deposit. Fingermark contrast was achieved as a result of active co-crystallization (giving purple polymer) in either the ridges or the furrows, depending upon the surface and other factors. A general observation (supported by spot tests with linseed oil, salt and amino acid solutions) was that on paper, oily materials are more likely to lead to the formation of the purple polymer, while the presence of water inhibits polymerization. However, these observations are not consistent across all other substrates. It is hypothesized that water disrupts hydrogen bonding between diacetylene molecules, and thus prevents the topochemical polymerization of the diacetylenes, which occurs in the solid state between favourably aligned monomers. An interesting observation was the development of fingermarks deposited on paper that had already been treated with the diacetylene reagent. 相似文献
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Bloodstain evidence is a highly valued form of physical evidence commonly found at scenes involving violent crimes. However, painting over bloodstains will often conceal this type of evidence. There is limited research in the scientific literature that describes methods of detecting painted-over bloodstains. This project employed a modified digital single-lens reflex camera to investigate the effectiveness of infrared (IR) photography in detecting latent bloodstain evidence beneath a layer or multiple layers of paint. A qualitative evaluation was completed by comparing images taken of a series of samples using both IR and standard (visible light) photography. Further quantitative image analysis was used to verify the findings. Results from this project indicate that bloodstain evidence can be detected beneath up to six layers of paint using reflected IR; however, the results vary depending on the characteristics of the paint. This technique provides crime scene specialists with a new field method to assist in locating, visualizing, and documenting painted-over bloodstain evidence. 相似文献