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141.
Announcement     
The process of calibrating a tachograph makes use of a mechanical head drive unit and an electronic clock tester. Both these devices should be checked against a standard at 6-month intervals. The design of such a substandard, based on a highly stable 1 MHz crystal oscillator, is described.  相似文献   
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IsiXhosa literary critics have not yet interrogated literature that was produced during and after the tenure of Thabo Mvuyelwa Mbeki as deputy president and president of the Republic of South Africa in order to study the impact of his African Renaissance doctrine. This article analyses poetry that was produced from 2005 to 2011. The content of the isiXhosa written poetry is profoundly influenced by the context of former President Mbeki's African Renaissance philosophy, its implementation structures and philosophy of self-confidence and self-reliance. The selected poems analysed and interpreted in this article suggest that Mbeki's legacy of the African Renaissance empowered poets to develop a narrative that advances the building of a regenerated South African nation and the African continent. Selected poetry of the period is contextualised, and the findings reveal that the poets have a dialectical relationship with historical developments of the time, and that they demonstrate acquiescence to the African Renaissance ideology, and support the operational structures created; namely African Union, Pan-African Parliament and the Vuk’uzenzele programme.  相似文献   
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Hanson  Russell L. 《Publius》1991,21(2):63-81
The impact of political culture on state politics has been investigatedwidely, but little is known about the relationship between politicalculture and economic development policy, even though such policiesplay a prominent role in contemporary state politics. DrawingonDanielJ. Elazar's analysis of American political subcultures,I suggest that moralistic, individualistic, and traditionalisticvalues imply quite different strategies for promoting economicgrowth Empirical evidence shows that moralistic states pursuestrategies that emphasize solidarity, while individualisticstates employ policies that confer particularistic benefitson investors. For their part, policymakers in traditionalisticstates prefer exclusionary incentives that tend to reinforceexisting patterns of domination. Whether any of these strategiessucceed in realizing their cultural objectives remains to beseen; however, actions that positively affect economic performancemay lead to the erosion of cultural values by triggering migrationsthat bring new values into play.  相似文献   
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The inadvertent transmission of AIDS virus through contaminated whole blood has shaken the viability of the American voluntary blood supply system. For the first time since the voluntary donor system replaced the commercial blood system, there are widespread doubts about the ability of blood suppliers to meet the nation's increasing health care demands. This paper presents a framework for analyzing blood collection. First, we critique the existing literature on blood collection, arguing that its focus on donor motivation is difficult to integrate with policy analysis. We then present a specific model of the individual's decision to donate blood as a comparison of the costs and benefits of donating. The current system of collecting whole blood relies on donors receiving only altruistic benefits. We explore the limits of this approach to dealing with the quantity and quality problems presented by the AIDS virus. Alternative approaches....  相似文献   
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This study examines the influence of three-layered cranial architecture development upon blunt force trauma (BFT) cranial outcomes associated with pediatric non-accidental injury (NAI). Macroscopic and microscopic metric and morphological comparisons of subadult crania ranging from perinatal to 17 years of age chronicle the ontogenetic development and spatial and temporal variability in the emergence of a mature cranial architecture. Cranial vault thickness increases with subadult age, accelerating in the first 2 years of life due to rapid brain growth during this period. Three-layer differentiation of the cranial tables and diploë initiates by 3–6 months but is not consistently observed until 18 months to 2 years; diploë formation is not well developed until after age 4 and does not manifest a mature appearance until after age 8. These results allow topographic documentation of cortical and diploic development and temporal and spatial variability across the growing cranium. The lateral cranial vault is identified as expressing delayed development and reduced expression of the three-layer architecture, a pattern that continues into adulthood. Comparison of fracture locations from known BFT pediatric cases with identified cranial fracture high-risk impact regions shows a concordance and suggests the presence of a higher fracture risk associated with non-accidental BFT in the lateral vault region in subadults below the age of 2. The absence or lesser development of a three-layered architecture in subadults leaves their cranial bones, particularly in the lateral vault, thin and vulnerable to the effects of BFT.  相似文献   
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The presence of diatom algae in bone marrow has been used as forensic evidence of drowning for several decades; however, these studies are based on known or suspected recent drowning events. This study addresses the potential for diatoms to enter the bone marrow of skeletal remains, that is, de-fleshed long bones post-mortem. In laboratory and field experiments, bones were either inflicted with two access points by a cut and acid pitting or left intact. The bones were submerged in water for at least 1 week and up to 3 months. Samples of the bone surface and marrow were inspected for diatoms. The analysis considered the time required for diatoms to enter marrow and whether genus characteristics like size or mobility affect entry. The presence of an access point influenced diatom entry in that bones without an introduced access point had zero to one diatom present in the marrow, whereas a bone with an access point had >150 diatoms present in the marrow. The results of both laboratory and field phases suggest that diatoms will reliably colonize bone in as quickly as 1 week, establishing and maintaining communities for at least 3 months. However, the bone surface assemblages differ from the source community. Bone marrow displayed even more restrictive access to diatom colonization, resulting in communities dominated by small raphid diatoms. Based on these findings, we suggest some caveats on the use of diatoms as trace evidence in forensic science with recommendations for future avenues of research.  相似文献   
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