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81.
V P Poluianov 《Sudebno-meditsinskaia ekspertiza》1990,33(4):34-36
The analysis of naphthenic acid revealed that they may be used for tin detection in the cadaveric material due to their high complex-forming ability. Method of extraction-atomic absorption tin determination in human organs was developed on the basis of naphthenic acid use. Modified method which differs from the common one by higher sensitivity and selectivity is presented. 相似文献
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Helena Teixeira Paula Proena Alain Verstraete Francisco Corte-Real Duarte Nuno Vieira 《Forensic Science International Supplement Series》2005,150(2-3):205
An analytical method using solid-phase extraction (SPE) and high-performance liquid chromatography–mass spectrometry (LC–MS) has been developed and validated for the confirmation of Δ9-tetrahydrocannabinol (THC) in oral fluid samples. Oral fluid was extracted using Bond Elut LRC-Certify solid-phase extraction columns (10 cm3, 300 mg) and elution performed with n-hexane/ethyl acetate. Quantitation made use of the selected ion-recording mode (SIR) using the most abundant characteristic ion [THC + H+], m/z 315.31 and the fragment ion, m/z 193.13 for confirmation, and m/z 318.00 for the protonated internal standard, [d3-THC + H+]. The method proved to be precise for THC, in terms of both intra-day and inter-day analyses, with coefficients of variation less than 10%, and the calculated extraction efficiencies for THC ranged from 76 to 83%. Calibration standards spiked with THC between 2 and 100 ng/mL showed a linear relationship (r2 = 0.999). The method presented was applied to the oral fluid samples taken from the volunteers during the largest music event in Portugal, named Rock in Rio-Lisboa. Oral fluid was collected from 40 persons by expectoration and with Salivette®. In 55% of the samples obtained by expectorating, THC was detected with concentration ranges from 1033 to 6552 ng/mL and in 45% of cases THC was detected at concentrations between 51 and 937 ng/mL. However, using Salivette® collection, 26 of the 40 cases had an undetectable THC. 相似文献
86.
This study investigated the influence of an authority figure on eyewitness identification. Participants watched a staged crime
and then were administered a photo lineup by either an authority (policeman) or non-authority figure (civilian). Participants
in the authority condition were more likely to choose a lineup member than those in the non-authority condition. There was
no effect of authority, however, on the accuracy of the identification decisions. The lack of a deleterious effect suggests
that the presence of a police officer during identification procedures does not create an unduly suggestive situation or have
undesirable effects on eyewitness identification decisions. Although witnesses' choosing behaviors did not increase the rate
of identification errors, the effect of the administrator's authority on choosing was reduced when unbiased instructions (vs.
biased instructions) were presented to the witnesses. Thus, support was found for the use of neutral instructions during eyewitness
identification procedures. 相似文献
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The Federalist claims to present a republican response to thetypical political problems faced by republics. That solutionrequired a departure from all models of republics known at thattime, and in particular a break with Anti-Federalist modelsthat posited heavy reliance on responsibility, understood aseither political accountability or as moral and political virtue.The Federalist challenges the Anti-Federalist notion that a"no-gap polity" is the means to safe and effective republicanism.It also challenges those who believe that virtue of people orrulers is the precondition of a republican polity. Publius doesrequire quasi-virlues of certain sortsand thus does notrely entirely on calculating selfinterestbut these aresignificantly different from the virtues posited by earlierrepublican theorists or certain contemporary interpreters ofThe Federalist. 相似文献
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