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101.
102.
Average human life expectancies for the U.S. resident population are calculated using tabulated population and survival rate data. These life expectancies are recalculated assuming elimination of various types of motor vehicle fatalities using Fatal Accident Reporting System (FARS) data. The differences between the original and recalculated values provide estimates of life expectancy reductions due to the motor vehicle fatalities. These estimates are combined with prior work relating the likelihood of an occupant fatality to car mass, so that reductions in life expectancy are determined as a function of car mass. The estimates of life expectancy reductions are also used to determine the effect of seat belt use on life expectancy. The estimates, which are based on data for 1978, assume that survival rates remain unchanged. Estimates of the changes in life expectancy associated with switching from a large (1800 kg) car to a small (900 kg) car, and switching from not using to using a seat belt are presented as functions of the age at which an individual makes the switch.  相似文献   
103.
Resistance training has been shown to be the most effective exercise mode to induce anabolic adaptations in older men and women. Advances in imaging techniques and histochemistry have increased the ability to detect such changes, confirming the high level of adaptability that remains in aging skeletal muscle. This brief review presents a summary of the resistance-training studies that directly compare chronic anabolic responses to training in older (>60 years) men and women. Sixteen studies are summarized, most of which indicate similar relative anabolic responses between older men and women after resistance training. Relatively small sample sizes in most of the interventions limited their ability to detect significant sex differences and should be considered when interpreting these studies. Future research should incorporate larger sample sizes with multiple measurement time points for anabolic responses.  相似文献   
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This paper presents a relative cohort size model of suicide. The model states that as relative cohort size (the ratio of younger to older workers) rises, income and income aspirations diverge for the young. One possible extreme reaction to this disequilibrium is suicide. The model explains the variation in age- and sex-specific suicide rates for the United States over the period 1948 to 1976. It identifies the direct effect of changes in cohort size on suicide rates as well as the indirect effect operating through other demographic variables. The model predicts the suicide rates for males above 45 years of age to rise and those for all other groups to decline. For most groups this is a reversal of recent movements in their suicide rates.  相似文献   
106.
Abstract

Dominance analysis is a procedure for measuring the importance of predictors in multiple regression analysis. We show that dominance analysis can be enhanced using a dynamic programing approach for the rank-ordering of predictors. Using customer satisfaction data from a call center operation, we demonstrate how the integration of dominance analysis with dynamic programing can provide a better understanding of predictor importance. As a cautionary note, we recommend careful reflection on the relationship between predictor importance and variable subset selection. We observed that slight changes in the selected predictor subset can have an impact on the importance rankings produced by a dominance analysis.  相似文献   
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Abstract

Serials and the serials information chain have changed rapidly since the development of the electronic journal. Many recent developments are briefly described, including electronic resource management systems (ERMS) and functional requirements for bibliographic records (FRBR). The constantly changing nature of serials is compared to a psychological midlife crisis.  相似文献   
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