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1.
This paper describes the analytical methodology for the determination of MDMA, MDA, MDEA and MBDB in oral fluid. After a liquid–liquid extraction, the analysis was carried out by high performance liquid chromatography (HPLC), with fluorescence detection. The detector wavelength was fixed at 285 nm for excitation and 320 nm for emission. The mobile phase, a mixture of phosphate buffer (pH = 5) and acetonitrile (75:25), and the column, Kromasil 100 C8 5 μm 250 mm × 4.6 mm, allowed good separation of the compounds in an isocratic mode in only 10 min. The method was validated and showed good limits of detection (2 ng/mL) and quantitation (10 ng/mL) for all the amphetamine derivatives. No interfering substances were detected. A stability study of these compounds in oral fluid stored at three different temperatures (−18, 4 and 20 °C) over 10 weeks was conducted, showing a time-dependent degradation of the four compounds.  相似文献   
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DNA is one of the fastest growing tools in forensic sciences, increasing reliability in forensic reports and judgments. The use of DNA has increased in different areas of the forensic sciences, such as investigation of plant species, where plastid DNA has been used to elucidate and generate evidence in cases of traceability of genetically modified and controlled plants. Even with several advances and the practice of using DNA in forensic investigations, there are just few studies related to the identification of genetic tools for the characterization of drug and nondrug-types of Cannabis. Herein, the whole plastomes of two drug-type Cannabis are presented and have their structures compared with other Cannabis plastomes deposited in the GenBank, focusing in the forensic use of plastome sequences. The plastomes of Cannabis sativa “Brazuka” and of the hybrid Cannabis AK Royal Automatic presented general structure that does not differs from the reported for other C. sativa cultivars. A phylogenomic analyses grouped C. sativa “Brazuka” with the nondrug C. sativa cultivars, while the hybrid Cannabis AK Royal Automatic placed isolated, basal to this group. This suggests that the analysis of plastomes is useful toward genetic identification of hybrids in relation to C. sativa.  相似文献   
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Public Choice - Although often at the heart of the public debate, the underlying determinants of political selection and voters’ punishment of corrupt politicians remain poorly investigated....  相似文献   
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International Journal for the Semiotics of Law - Revue internationale de Sémiotique juridique - This paper discusses the creation and use of the new Macquarie Laws of War Corpus (MQLWC). The...  相似文献   
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Behavioral interventions appealing to taxpayers’ reciprocity often leave tax compliance unaffected. We provide evidence that a “fiscal exchange nudge” increased tax compliance in a setting where one might not expect it: crisis-ridden Argentina. In a randomized controlled trial with over 20,000 taxpayers, a tax bill visually celebrating realized public works benefiting children increased payment rates of tax delinquents by about 20 percent, or almost 40 percent when the bills were delivered in person. Without the appeal, the new bill design generated significantly fewer payments. Changes in the design of the tax bill also increased arrears cancellation. We estimate the ratio of marginal revenues to costs for the fiscal exchange bill to be 18. The factors we associate with the unexpectedly positive impacts are consistent with strengthening an affective response. We find persistent effects of the experiment two years later. The results suggest that communities have more scope to increase tax revenues through non-threatening interventions.  相似文献   
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The objective was to investigate color change and surface damage in dental resin composites exposed to high temperatures over different time intervals for comparative purposes. Samples were prepared using two resins - Z100(R) (R1) and Charisma (R2), heated at the following temperatures: 200 degrees C, 400 degrees C, 600 degrees C, 1000 degrees C, for 15, 30 and 45 min (n = 104 for each resin sample). Color (DeltaE) and brightness (DeltaL) changes were analyzed by spectrophotometry using the CIE Lab system and surface changes by Scanning Electron Microscopy (SEM). R1 showed more intense color changes after heat exposure than R2. DeltaL values were found to be the best parameter for evaluation of light and color change. A biphasic pattern after thermal exposure was detected, from dark brown to light white. SEM showed more intense alterations in R2 than in R1. These results indicate that the parameters observed in both resins are useful as a guide in forensic analyses.  相似文献   
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Using a data set that covers all Portuguese mainland municipalities for the period 1979–2005, this study performs an empirical analysis of the economic determinants of mayors’ decisions to run for another term in office. The literature on the subject is mainly centered on the United States and, as far as we know, there are no papers addressing the economic factors influencing those choices. Probit panel estimations show that local economic conditions matter more than the national or regional economic environment. The results also confirm that political variables are important and that they influence the likelihood of seeking reelection in much the same way as they affect vote and popularity functions.  相似文献   
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