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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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Abstract: Policy institutes are prominent members of policy communities in Canada, but there is little understanding of their diversity beyond well-known value orientations, nor of how they differ from other “think tank” organizations such as government councils and academic research centres. This paper supplies concepts and a framework for assessing the capacity and role of policy institutes. It compares the size and activities of several well-known Canadian institutes, and puts their emergence in historical context. The paper concludes with suggestions on how to make institutes more relevant to the policy-making process. Sommaire: Les instituts de politique sont des membres bien connus de la collectivité d'analyse des politiques au Canada, mais on comprend peu leur diversité (au-delà de leurs orientations bien connues), et on voit mal en quoi ils diffèrent d'autres groupes de réflexion comme les conseils gouvernementaux et les centres de recherches universitaires. Le présent article offre des concepts et un cadre permettant d'évaluer la capacité et le rôle des Instituts de politique. II compare la taille et les activités de plusieurs instituts canadiens bien connus et il place leur émergence dans un contexte historique. Dans sa conclusion, l'article suggère des moyens permettant d'impliquer davantage les instituts dans le processus de définition des politiques.  相似文献   
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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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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   
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Although representative payeeship is prevalent among people with mental illness and shows promise to positively influence clinically relevant outcomes, research also suggests this legal mechanism could be implemented in ways that are problematic. The current study examined whether family representative payeeship was associated with elevated risk of family violence perpetrated by persons with severe mental illness (SMI). Data were collected every 4 months for 1 year in structured interviews with N = 245 persons with SMI who received disability benefits. Multivariate analyses showed that substance abuse, history of violence, frequency of family contact, and family representative payeeship were associated with elevated odds of family violence. Analyses also showed family contact and family representative payeeship had a cumulative effect on increasing the predicted probability of family violence (controlling for covariates such as violence history and substance abuse). The data shed light on the potential for family representative payeeship to be associated with increased risk of interpersonal conflict and violence in SMI.  相似文献   
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