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51.
In rabbits, intracerebrally applied erythrocytes can move with the cerebrospinal fluid along connecting pathways between the subarachnoid space and the cervical lymph nodes. This study compares the time dependency for the degradation of intracerebrally injected erythrocytes in the brain as well as in the cervical lymph nodes. Rabbits were killed at various predetermined intervals after the intracerebral erythrocyte injection. Microscopic and histologic examination of the brain and the cervical lymph nodes revealed the following findings: (1) Erythrophages first appeared in the brain 24 h after the injection; siderophages, 4 days after the injection. Siderophages were still demonstrable at the conclusion of the study, i.e. 240 days after the injection. (2) In the cervical lymph nodes erythrophages were first observed 1 h after the injection; siderophages, 9 h after the injection. Only isolated erythrophages and siderophages were found in the lymph nodes 12 days after intracerebral injection of red blood cells. Later on no erythrocytes or siderophages were observed in the lymph nodes. The findings indicate that non-phagocytized red blood cells arriving at the lymph nodes were ingested by local macrophages. The extremely rapid ingestion and digestion of the red blood cells by lymph node macrophages as well as the possible reasons were discussed.  相似文献   
52.
A case of fatal myocarditis in a 24-year-old otherwise healthy man is described. It was possible to cultivate Salmonella typhimurium from the alimentary tract, the blood, the liver and skeletal muscles. The possibility of a solitary myocarditis with fatal outcome due to Salmonella typhimurium infection is discussed. Such a case seems not to have been mentioned previously in the literature.The problems concerning the statistical registration of such a death are briefly discussed.  相似文献   
53.
The purpose of this study was to specify the effects of alcohol on the performance of ship operators as a contribution to the development of new strategies against the risks of alcohol in water traffic. The nautical performance of 21 captains before and after alcohol consumption was assessed on a ship piloting simulator. The simulated scenarios represented passages of a container vessel through the German Bight. Performance was examined by nautical instructors according to standardised protocols. Mean (S.D.) blood alcohol concentrations (BACs) of 0.100 (0.024) g/dl before and 0.100 (0.017) g/dl after the performance trial resulted in striking effects on the nautical performance. The categories most severely affected were foresight and analysis of situation (impairment in 18 of 21 cases), concentration (impairment in 16 of 21 cases), accurateness, risk disposition and navigation (impairment in 15 of 21 cases). Chart work, preparation and communication were impaired in 12, 11 and 10 of 21 cases, respectively. None of the participants were capable to operate the simulated ship with an adequate safety after ingestion of alcohol. From these findings, and in consideration of the well-established impairment of a multitude of mental and physical functions by alcohol, it can be concluded that even low BACs bear high risks in water traffic, a concentration above 0.1 g/dl will hinder a sufficiently safe performance of ship operators. This should be considered in alcohol education and legislation.  相似文献   
54.
As European majority members are often hostile toward ethnic minorities, it is important to identify sources that reduce opposition to immigrants. First, focusing on Denmark, this article examines whether intergroup contact influences attitudes toward ethnic minority rights (henceforth: ‘ethnic tolerance’). Second, this study tests whether the contact‐tolerance relationship is mediated by self‐disclosure and symbolic threat. Furthermore, contact is measured as workplace contact in order to reduce self‐selection biases. The empirical tests are performed on a Danish high‐quality national probability sample from 2009 (N = 1,929). Analysis shows that intergroup contact generates ethnic tolerance because workplace contact weakens threat perceptions and stimulates disclosure of personal information. Generally, these results suggest that regular intergroup contact can improve ethnic relations in contemporary democracies.  相似文献   
55.
Abstract: The chemical profiling of illicit drugs is an important analytical tool to support the work of investigating and law enforcement authorities. In our work, comprehensive two‐dimensional gas chromatography–time‐of‐flight mass spectrometry (GC × GC‐TOFMS) combined with nontargeted, pixel‐based data analysis was adapted for the chemical profiling of 3,4‐methylenedioxymethamphetamine (MDMA). The validity and benefit of this approach was evaluated by analyzing a well‐investigated set of MDMA samples. Samples were prepared according to a harmonized extraction protocol to ensure the comparability of the chemical signatures. The nontargeted approach comprises preprocessing followed by analysis of variances as a fast filter algorithm for selection of a variable subset followed by partial least squares discriminant analysis for reduction to promising marker compounds for discrimination of the samples according to their chemical profile. Forty‐seven potential marker compounds were determined, covering most of the target impurities known from the harmonized one‐dimensional profiling as well as other compounds not previously elucidated.  相似文献   
56.
Choosing the number of seats in a legislature is a balancing act between efficiency and representativeness. This article focuses on representativeness and hypothesises that the larger the assembly, the higher the vote–seat proportionality, the higher the number of parties represented, and the higher the representation of otherwise under-represented groups. An approach using simulations of elections is introduced and applied in testing the hypotheses in the case of Danish local elections. Two thousand six hundred and forty-six elections are simulated, and a positive, but non-linear, relationship is demonstrated between number of seats and proportionality, number of parties, and percentage of women councillors.  相似文献   
57.
ABSTRACT

Right-wing Eurosceptic political groups gained ground in the elections for the European Parliament in May 2014. The electoral victory of right-wing Euroscepticism was accompanied by a concern that populism is (once again) spreading in Europe. Associating right-wing Eurosceptics with populism raises the question of whether critiques of populism can be directly extended to right-wing Euroscepticism. By reconstructing the right-wing Eurosceptic concept of ‘the people,’ this article demonstrates that the Eurosceptic concept of the people has a dual meaning that encompasses both a transnational and a national concept of the people. The article concludes that while Euroscepticism shares ideological features with populism, it is problematic, due to the internal structure of the promoted concept of the people and the European political environment, directly to extend recent critiques of populism to right-wing Euroscepticism.  相似文献   
58.
ABSTRACT

Many government services are delivered by (partially) autonomous agencies. Governments need effective measures for contracting, steering, and monitoring agencies and to balance control and trust. In the literature, control-based agency theory and trust-based stewardship theory have often been portrayed as alternative and competing approaches. In empirical studies in public administration, however, these approaches often find mixed and contradictory results. Against this background, this article analyzes how a combination of trust- and control-based approaches, explicitly founded on agency and stewardship theory, can help explain when participants find a given governance regime to be most satisfactory. A survey instrument is developed which, for the first time, fully measures the rich concept of stewardship theory in conjunction with agency theory. The analysis of the governance of Dutch agencies shows that government indeed combines governance solutions from both theoretical camps and illuminates under which conditions this combination is most satisfactory.  相似文献   
59.
ABSTRACT

SOCMINT (SOCial Media INTelligence) is increasingly considered relevant and cost efficient information, and the exploitation of social media information in the name of security and public safety is generally regarded as unproblematic. We will critically scrutinize this claim and argue that the exploitation of such information by Intelligence and Security Services raises new ethical concerns. Drawing on recent moral discussions about privacy, we will argue that individuals have an interest in privacy in public spaces, including online spaces. We will discuss the role of such public privacy interests and argue that the systematic surveillance of social media platforms by security authorities potentially entail a negative chilling effect.  相似文献   
60.
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