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21.
Insurance claims were examined for evidence of neck injuries to drivers of passenger cars struck in the rear. Neck injury rates were significantly lower for male drivers, elderly drivers, and drivers in less severe crashes. Even after accounting for differences in driver demographics and crash severity, neck injury rates were significantly lower for drivers of cars with head restraints that were more likely to be behind the heads of motorists.  相似文献   
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The psychometric properties of the newest version of the Temperament and Character Inventory (the TCI-R) were evaluated in a large (n = 727) community sample, as was the TCI-140, a short inventory derivative. Facets-to-scale confirmatory and exploratory factor analyses of the TCI-R did not support the organization of temperament and character facet scales within their superordinate domains. Five of the 29 facet scales also displayed relatively low internal consistency (α  相似文献   
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In this article we overview the design and implementation of the second generation of Kansas Lava. Driven by the needs and experiences of implementing telemetry decoders and other circuits, we have made a number of improvements to both the external API and the internal representations used. We have retained our dual shallow/deep representation of signals in general, but now have a number of externally visible abstractions for combinatorial and sequential circuits, and enabled signals. We introduce these abstractions, as well as our abstractions for reading and writing memory. Internally, we found the need to represent unknown values inside our circuits, so we made aggressive use of associated type families to lift our values to allow unknowns, in a principled and regular way. We discuss this design decision, how it unfortunately complicates the internals of Kansas Lava, and how we mitigate this complexity. Finally, when connecting Kansas Lava to the real world, the standardized idiom of using named input and output ports is provided by Kansas Lava using a new monad, called Fabric. We present the design of this Fabric monad, and illustrate its use in a small but complete example.  相似文献   
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The levels of lead in city street dirt and in soil from various locations in Glasgow were investigated during spring 1976. Lead concentrations in street dirt ranged from 150–2300 ppm, mean 960 ppm, and were significantly elevated with respect to the observed “natural” level of 78 ppm. Lead derived from anti-knock compounds in petrol and introduced to the environment via automobile exhausts was clearly implicated as the main source of lead pollution in a series of soil lead measurements at the centre and periphery of eight Glasgow parks.Various chemical leaching techniques were employed and compared. Less than 5% of street dirt and soil lead was found to be associated with the organic phase.  相似文献   
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