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After a rather uneventful election campaign, the results of the May 1986 Dutch parliamentary election were a surprise to virtually all involved. Since the introduction of regular opinion polling in the 1960s, no election has taken place when the polls were ‘wrong’. However, in 1986 last minute shifts that were stronger than had ever occurred in the Netherlands produced results that differed significantly from the predictions based upon the polls published immediately prior to the election. 相似文献
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Meissner C Recker S Reiter A Friedrich HJ Oehmichen M 《Forensic science international》2002,130(1):49-54
The study was performed to distinguish fatal from non-fatal blood concentrations of morphine. For this purpose, blood levels of free morphine and total morphine (free morphine plus morphine conjugates) in 207 cases of heroin-related deaths were compared to those in 27 drivers surviving opiate intoxication. The majority of both survivors and non-survivors were found to show a concomitant use of depressants including alcohol or stimulants. Blood morphine levels in both groups varied widely, with a large area of overlap between survivors (free morphine: 0-128 ng/ml, total morphine: 10-2,110 ng/ml) and non-survivors (free morphine: 0-2,800 ng/ml, total morphine: 33-5,000 ng/ml). Five (18.5%) survivors and 87 (42.0%) non-survivors exhibit intoxication only by morphine. In these cases, too, both groups overlapped (survivors-free morphine: 28-93 ng/ml, total morphine: 230-1,451 ng/ml; non-survivors-free morphine: 0-2,800 ng/ml, total morphine: 119-4,660 ng/ml). Although the blood levels of free or total morphine do not allow a reliable prediction of survival versus non-survival, the ratio of free/total morphine may be a criterion to distinguish lethal versus survived intoxication. The mean of the ratio of free to total morphine for all lethal cases (N=207) was 0.293, for those that survived (N=27) 0.135, in cases of intoxication only by morphine 0.250 (N=87) and 0.080 (N=5), respectively. Applying a cut-off of 0.12 for free/total morphine and performing ROC analyses, fatal outcome can be predicted in 80% of the cases correctly, whereas 16% of the survivors were classified as dead. Nevertheless, in this study, all cases with a blood concentration of 200 ng/ml and more of free morphine displayed a fatal outcome. 相似文献
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Clauwaert KM Van Bocxlaer JF Lambert WE De Leenheer AP 《Forensic science international》2000,110(3):157-166
Hair samples of eight postmortem cases were analyzed in segments of 1 to 3 cm for cocaine, benzoylecgonine and cocaethylene. Samples were prepared for analysis by digestion in 0.1 M HCl and subsequent extraction with mixed-mode solid-phase extraction columns. Measurement was made by reversed-phase, narrow-bore HPLC and fluorescence detection using two laboratory-made internal standards. The concentrations were in the region of 0.29-316 ng/mg of hair for cocaine, 0.43-141 ng/mg of hair for benzoylecgonine and 0.93-1.83 ng/mg of hair for cocaethylene. All eight investigated cases had cocaine-positive segments. In six of the cases, all segments were positive, suggesting regular cocaine use and two showed in-between negative segments indicating an interruption or a change of the abuse intensity. The results showed a second, remarkable observation, i.e. enormous concentration differences (factor >150) for both cocaine and benzoylecgonine between the different subjects. Furthermore, interindividual cocaine/benzoylecgonine ratios ranged from 0.02 to 8.43. We believe these observations could in part be attributed to both some of the still existing limitations in the analytical approach(es), especially the mandatory hair washing steps, and in our still too limited knowledge of the hair incorporation processes. Nevertheless, in some cases, segmental analysis proved to be an important tool to distinguish, together with postmortem examination, deadly chronic abuse from single acute drug overdosage. 相似文献
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Massonnet G Buzzini P Jochem G Stauber M Coyle T Roux C Thomas J Leijenhorst H Van Zanten Z Wiggins K Russell C Chabli S Rosengarten A 《Journal of forensic sciences》2005,50(5):1028-1038
A collaborative study on Raman spectroscopy was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on three dyed fibers: two red acrylics and one red wool. Raman instruments from six different manufacturers were tested as well as nine different laser wavelengths ranging from blue (lambda = 458 nm) to near infrared-NIR (lambda = 1064 nm). This represents the largest comparison study of Raman analytical parameters carried out on identical fiber samples. For the chosen fiber and dye samples, red lasers (lambda = 633 and 685 nm) gave the poorest spectral quality whereas blue (458 nm), green (514 nm) and near infrared lasers (785, 830 and 1064 nm) provided average results. Blue (488 nm) and green lasers (532 nm) globally gave the best quality spectra. Fluorescence problems were often encountered with some of the excitation wavelengths and therefore a flexible Raman instrument equipped with different lasers can be recommended to measure forensic fiber samples. The instrument should also be equipped with a Raman microscope in order to be able to focus on a single fiber. This study shows that Raman spectroscopy usually enables the identification of the main dye present in a colored fiber; however, minor dye components are much more difficult to detect. SERRS (Surface Enhanced Resonance Raman Scattering) techniques give an improvement of the dye's spectral intensity but no spectral improvement was observed for the two red acrylic and red wool fibers tested. 相似文献