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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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A 6-year longitudinal panel study investigated the absolute and relative stability in depressed mood throughout adolescence by reporting data from a sample of 538 adolescents between 13 and 19 years of age. Results revealed the following. (1) Girls had on average higher depressed mood scores than boys at all ages. (2) Among boys there were no substantial changes in depressed mood mean scores, while among girls there was a slight tendency of a curvilinear trend, with a peak level reached in midadolescence. (3) There was a tendency for adolescents to retain their relative level in depressed mood, most pronounced for a period of 4 years, from age 15 to age 19 years. (4) Depressed mood was most stable in a subgroup of adolescents who had high initial depressed mood scores. (5) By applying structural equation modeling, it was shown that the stable (trait) component of depressed mood increased in importance with increasing age, while the temporal (state) component decreased with increased age. 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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ABSTRACTThe Turkish Armed Forces (TAF) have been the main discussion topic in the political arena over the last decade in Turkey, with a focus on curtailing military supervision over political life. This article investigates the evolution of civil–military relations (CMR) in Turkey. Thus, the aim of this study is to explore the factors and dynamics that have led to the development and realignment of CMR in Turkey. The focus will be on how military tutelage in Turkey has been ended, what factors have caused this and finally whether Turkish CMR have been normalized. 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