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Abstract In several recent studies George Rabinowitz and his co–authors challenge the 'classical' spatial model of issue voting, the proximity model, by introducing a directional model. In this article we examine whether different measurement of perceived issue positions of candidates or parties leads to diverging judgments about the predictive power of the directional model (which is claimed to be empirically superior), as compared to the proximity model, using data from the USA and Germany. The results demonstrate that the measurement preferred by Rabinowitz et al. tends to bias empirical findings in favour of directional theory. If we use a more plausible operational definition of issue positions of candidates and parties the directional model in both countries fails to turn out superior. 相似文献
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Fentanyl is a very strong opioid with analgesic properties that are approximately 80 times stronger than those of morphine and therefore is used in major surgery and treatment of pain in tumor patients. Cases of fentanyl abuse by intravenous injection, inhalation, oral or nasal application have been reported especially in the USA. Therapeutic levels of fentanyl are as low as 1 ng/ml of serum and therefore a screening test must have a detection limit below that concentration. Recently three non-radioactive enzyme immunoassays (EIAs) have become commercially available from COZART, STC and DIAGNOSTIX, all of them supplied by MAHSAN Diagnostika for evaluation with serum samples from forensic and clinical cases. A calibration curve is obtained with samples that contain 0, 0.1, 0.5, 1 and 5 ng fentanyl per ml of negative serum. The calibration curve of COZART is especially in the low range, steeper than those of STC and DIAGNOSTIX. The cut-off for all these EIAs, however, can be set at 0.5 ng/ml. After the administration of therapeutic doses, fentanyl concentrations were between 3 and more than 5 ng/ml as determined with the EIAs. The presence of the typical drugs of abuse, e.g. heroin, methadone, cocaine, cannabinoids and amphetamines including the derivatives of methylenedioxyamphetamine, don't generate false-positive results. No cross-reactivity was also observed at toxic levels of benzodiazepines and paracetamol and therapeutic levels of barbiturates, phenothiazines, antidepressants and analgesics. The EIAs tested so far appear to be suitable for the detection of fentanyl at therapeutic levels. False-positive results or cross-reactivity towards other compounds have not been observed. 相似文献
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3,4-methylenedioxyamphetamine (MDA) derivatives are increasingly abused central nervous system stimulants with neurotoxic properties. In recent years a number of controlled substance analogs (designer drugs) with high structural variety reached the illegal market making their identification an arduous task. The underivatized compounds give very similar or even virtually identical electron impact mass spectra containing mainly intense C(n)H(2n+2)N(+) immonium ions. Using tandem mass spectrometry (MS-MS) the additional structural information contained in the collision induced dissoziation (CID) mass spectra of molecular ions using electron impact (EI) and especially chemical ionization (CI) allowed an unequivocal differentiation of 18 studied regioisomeric 1-(methylenedioxyphenyl)-2-propanamines and 1-(methylenedioxyphenyl)-2-butanamines.Further synthetic methods are presented for 1-(3,4-methylenedioxyphenyl)-N-propyl-2-butanamine, N-isopropyl-1-(3,4-methylenedioxyphenyl)-2-butanamine and four 1-(2, 3-methylenedioxyphenyl)-2-butanamines. N-alkylated 1-(3, 4-methylenedioxyphenyl)-2-butanamine compounds (e.g. MBDB) are also known to be abused psychoactive agents (entactogenes) without the sympatomimetic effects of the 3,4-methylenedioxyamphetamines. 相似文献
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The first aim of this study was to examine the structure of externalizing and internalizing problem behavior during early
adolescence. Our second aim was to determine the stability of these problems for boys and for girls over time. A total of
650, 13–14-year-olds filled out (an expanded version of) the Youth Self-Report [YSR; Manual for the Youth Self-Report and 1991 Profile. Department of Psychiatry, University of Vermont, Burlington] 2 times with a 1-year interval. By using confirmatory factor
analyses (CFA) to test a series of competing models, a hierarchical model provided the best representation of the structure
of problem behavior at both Time 1 and Time 2: externalizing and internalizing problem behavior represent distinct aspects
but the model also demonstrates the existence of comorbidity at a higher level. This model appeared to be stable over time
for both boys and girls. The relative stability of problem behavior was found to be high for boys and girls. Absolute stability
for both externalizing and internalizing problems appeared to be higher for boys scoring in the lower range of problem behavior.
Senior Researcher, Utrecht University, The Netherlands. Received PhD in social sciences, University of Amsterdam. Major research
interests include problem behavior, family relations, and peer relations during adolescence.
Full Professor, Utrecht University, The Netherlands. Received PhD in social sciences: child and family studies, from University
of Nijmegen. Major research interests include adolescent social development, problem behavior, and family relations during
adolescence.
Assistant Professor, University of Amsterdam, The Netherlands. Received PhD in psychology, University of Amsterdam. Major
research interests include family influence on childhood illness and problem behavior. 相似文献
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Häkkänen H 《Forensic science international》2005,152(1):61-64
In Finland, homicide by ligature strangulation is a rare event. The purpose of this study was to investigate recent homicide cases by ligature strangulation and to analyse offence and offender characteristics. All forensic psychiatric evaluation statements of offenders accused of ligature strangulation homicides during the 7-year period 1996--2002 (n=19) were reviewed retrospectively. Thirty-five percent of the victims were females. In four cases, the victim was the offender's intimate partner; in one case, it was the stepson; in one case, a father and in the rest of the cases (n=13), an acquaintance. None of the cases involved planning, sadism or sexual elements. In 89% of the cases, the offender was either intoxicated or on drugs at the time of the offence and in 94% of the cases, the victim was found at the scene of the killing. Of the offenders, 63% had crime history, and approximately half of the offenders had experienced parental alcohol abuse, domestic violence or previous trauma. Most of the offenders were unemployed at the time of the offence. In all, 89% were diagnosed as having personality disorder and two were schizophrenic. 相似文献
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Schneider PM Bender K Mayr WR Parson W Hoste B Decorte R Cordonnier J Vanek D Morling N Karjalainen M Marie-Paule Carlotti C Sabatier M Hohoff C Schmitter H Pflug W Wenzel R Patzelt D Lessig R Dobrowolski P O'Donnell G Garafano L Dobosz M De Knijff P Mevag B Pawlowski R Gusmão L Conceicao Vide M Alonso Alonso A García Fernández O Sanz Nicolás P Kihlgreen A Bär W Meier V Teyssier A Coquoz R Brandt C Germann U Gill P Hallett J Greenhalgh M 《Forensic science international》2004,139(2-3):123-134
Degradation of human DNA extracted from forensic stains is, in most cases, the result of a natural process due to the exposure of the stain samples to the environment. Experiences with degraded DNA from casework samples show that every sample may exhibit different properties in this respect, and that it is difficult to systematically assess the performance of routinely used typing systems for the analysis of degraded DNA samples. Using a batch of artificially degraded DNA with an average fragment size of approx. 200 bp a collaborative exercise was carried out among 38 forensic laboratories from 17 European countries. The results were assessed according to correct allele detection, peak height and balance as well as the occurrence of artefacts. A number of common problems were identified based on these results such as strong peak imbalance in heterozygous genotypes for the larger short tandem repeat (STR) fragments after increased PCR cycle numbers, artefact signals and allelic drop-out. Based on the observations, strategies are discussed to overcome these problems. The strategies include careful balancing of the amount of template DNA and the PCR cycle numbers, the reaction volume and the amount of Taq polymerase. Furthermore, a careful evaluation of the results of the fragment analysis and of automated allele calling is necessary to identify the correct alleles and avoid artefacts. 相似文献