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181.
182.
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   
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Recently, a metric approach to skeletal sex determination was published by Paiva and Segre which is based on the summation of two triangular areas defined by three distinct craniometric landmarks: Porion, Mastoidale, and Asterion. According to the authors, values for the total triangle > or =1447.40 mm(2) are characteristic for male crania, while values < or =1260.36 mm(2) are indicative of female skulls (95% confidence). In order to evaluate the method's validity, two sex- and age-documented samples of different provenience were analyzed (N=197). The results show that while the indicated measurements display significant sex differences, the technique is of little practical meaning where a single individual must be independently classified. It is hypothesized that differences in the expression of sexual dimorphism as well as a population-specific variability of the asterion location undermine the value of the mastoid triangle as a sex determinant.  相似文献   
185.
Research on deception detection in legal contexts has neglected the question of how the use of evidence can affect deception detection accuracy. In this study, police trainees (N=82) either were or were not trained in strategically using the evidence when interviewing lying or truth telling mock suspects (N=82). The trainees’ strategies as well as liars’ and truth tellers’ counter-strategies were analyzed. Trained interviewers applied different strategies than did untrained. As a consequence of this, liars interviewed by trained interviewers were more inconsistent with the evidence compared to liars interviewed by untrained interviewers. Trained interviewers created and utilized the statement-evidence consistency cue, and obtained a considerably higher deception detection accuracy rate (85.4%) than untrained interviewers (56.1%).  相似文献   
186.
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   
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188.
Haplotype frequencies for 11 Y-STR markers (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS437, DYS438 and DYS439) in a Romani population (n=63) from Slovakia, Jats of Haryana (n=84) and Jat Sikhs (n=80) from India were determined. The Slovakian Romani, the Haryana and Sikh populations were endogamous based on their unique haplotype ratio and haplotype diversity values, although the Sikh population appeared to be more diverse. AMOVA revealed non-significant differences between the Romanies and significant differences with non-Romani populations. The Macedonian Romani population differed from all Romani populations examined. Frequent haplotypes observed in Romani populations were sporadic in northwest Indian populations. Thirteen out of 316 populations worldwide were found to share the six most frequent haplotypes of the Slovakian Romanies when the screening conditions were narrowed based on the population size to be over 40, the occurrence of the haplotypes was more than one and the sum frequencies of the most frequent haplotypes was at least 0.02. The most common haplotypes were also observed in other Romani groups. When searching with two Indian (Malbar and Malaysian Indian) most frequent haplotypes under the same conditions matches could be detected in all Romani populations except for the Macedonian Romanies. The search with the Jat Sikhs and Jats of Haryana most frequent haplotypes resulted no matches in Romani populations.  相似文献   
189.
This paper examines persistence and change in the Soviet Union's and then Russia's relations with Afghanistan with respect to development and security. First, a detailed analysis of the promise and reality of Soviet development assistance reveals conceptual shortcomings in their attempt to induce economic development in Afghanistan. The Soviet Union's heritage is then revealed in order to understand Russia's current perception of post-Taliban Afghanistan as well as Russia's emerging interests and commitment to Afghanistan's economic development. This paper argues that Russia will most likely replicate standard industrialization development approaches in contributing to Afghanistan's development. Therefore, Russia will probably run into problems similar to those that led to the failure of the Soviet modernization project, which consisted of large-scale development projects that were inappropriate to the country's institutions and the lives of most Afghans. It is questionable whether such reiteration will induce economic development now, in the complex setting of a fragmented and fragile state with a multitude of external players looking out for their own interests.  相似文献   
190.
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   
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