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911.
Early federal injury control programs in the 1960s and 1970s were centered first in the Division of Accident Prevention (Public Health Service) and subsequently in the National Highway Traffic Safety Administration (Department of Transportation) and the Consumer Product Safety Commission. The Centers for Disease Control (CDC) in the early 1970s also began to investigate injuries, particularly in the home and recreational environment. The field expanded in the 1970s and 1980s to include injuries that occur in many settings and both intentional injuries (violence) and unintentional injuries. After a 1985 report, Injury in America, CDC was chosen to be the national coordinating agency because of its mission of prevention. The current program also includes acute care, rehabilitation, and biomechanics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Inbreeding coefficients were computed for 910,444 animals of the Swiss Braunvieh population. Of the animals born in 1984, 71.5% were inbred with 67.9, 3.4, and .2% having inbreeding coefficients between greater than 0 and 5%, greater than 5 to 10%, and greater than 10%, respectively. The average inbreeding coefficient was 1.14% but, for animals with both parents and at least one grandparent known, it was 1.67%. Breeding values for total milk, fat, and protein yields and for fat and protein percentages were predicted using a repeatability animal model including a regression on the inbreeding coefficient. Phenotypic performance was sizeably depressed for milk yield only (-26 kg/% of inbreeding or 2.4% of the phenotypic standard deviation). Adjusting for inbreeding increased the estimated genetic trend slightly. Inbreeding is only partially accounted for when it is ignored in the construction of the inverse of the numerator relationship matrix. This effect was investigated by comparing predicted breeding values from a model including the complete matrix with predicted breeding values from a model including a matrix constructed with inbreeding ignored. Only .8% of all predicted breeding values were affected by more than +/- 5.5 kg. The maximum difference observed was 55.3 kg. The observed average absolute differences between the breeding values of offspring predicted with the two models increased with inbreeding of parents.  相似文献   
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The improved understanding of adsorption chemistry which has arisen from the development of new surface analytical techniques during the last twenty years has had a major effect on the understanding of catalytic reaction mechanisms. However, there are many other areas of technology where Interfacial chemistry has a determining role but where the understanding is much less developed. In this paper examples are presented of the role of interfacial chemistry in adhesion. In particular, It Is shown that modification of a surface to the extent of just a few atomic layers in depth can have dramatic effects on the performance of adhesive bonds, particularly when exposed to hostile environmental conditions. These examples will be used to highlight a need for greater fundamental understanding of the interfacial chemistry of adhesion and also other technologies where interface effects are dominant.  相似文献   
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