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If manufacturing a safer cigarette is technically possible--an open question--then mandating that tobacco manufacturers improve the safety of cigarettes would likely have both positive and negative implications for the nation's health. On the one hand, removing toxins may reduce the incidence of smoking-related diseases and premature mortality in smokers. On the other hand, smokers might be less inclined to quit, those who have quit might resume the habit, and youth who have never smoked will have one less reason to avoid tobacco use. To assess the expected population health impacts of a legislative or regulatory mandate, we created the Tobacco Policy Model, a system dynamics computer simulation model. The model relies on secondary data and simulates the U.S. population over time spans as long as 50 years. Our simulation results reveal that even if requiring cigarettes to be safer makes smoking more attractive and increases tobacco use, a net gain in population health is still possible.  相似文献   
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This article addresses a problem faced by many historians of living standards: what was the effect of unemployment on the real incomes of working-class families during industrialization? The 1901 Census of Canada offers a rare opportunity to answer this question, and to measure both unemployment and living standards while taking into account the contributions of all family wage-earners. The conclusion is that average weekly or monthly wages were more important than work duration in determining the living standards of poor families.  相似文献   
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Abstract

In this article, we conduct a generational study of measuring progress towards the inclusion of homosexuality in professional sport. We accomplish this by interviewing an openly gay football player, Anton Hysén, in the year 2017, using the precise same questions about the relationship between his homosexuality and sport that were asked of the first openly gay professional footballer in 1992, Justin Fashanu. We thus measure difference in attitude according to the 25 years that have elapsed between the interviews. Our results emphasize two themes: First, the near-total acceptance of being gay within professional football today, compared to 25 years ago; and second, the social praise that is levied upon today’s openly gay sportsmen, compared to the social stigma placed upon Fashanu.  相似文献   
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High‐throughput sequencing (HTS) of large panels of single nucleotide polymorphisms (SNPs) provides an alternative or complimentary approach to short tandem repeats (STRs) panels for the analysis of complex DNA mixture forensic samples. For STRs, methods to estimate individual contribution concentrations compare capillary electrophoresis peak heights, peak areas, or HTS allele read counts within a mixture. This article introduces three approaches (mean, median, and slope methods) for estimating individual DNA contributions to forensic mixtures for HTS/massively parallel sequencing (MPS) SNP panels. For SNPs, the major:minor allele ratios or counts, unique to each contributor, were compared to estimate contributor proportion within the mixture using the mean, median, and slope intercept for these alleles. The estimates for these three methods were typically within 5% of planned experimental contributions for defined mixtures.  相似文献   
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