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To determine the roles of mutation, migration, and selection in maintaining genetic variability in populations of house mice (Mus musculus), stochastic models based on characteristics of mouse populations inhabiting corn cribs in southwestern Ontario and the t allele were developed. Two sets of models were examined. One involved selection against t/t mice and a migration rate of 0.05 to 0.10 (low migration model) whereas the other involved selection against both t/t and +/t genotypes and a migration rate of 0.33 (high migration model). Both models could account for the t allele frequencies observed in natural populations. Similarly both models explain the frequencies observed at a second polymorphic locus, the Hbb locus which controls the β chain of the hemoglobin molecule, provided strong selection favoring the Hbb heterozygotes is incorporated. Without such selection pressure rapid extinction of one of the alleles at this locus occurred. A stabilizing force such as selection is considered necessary for the hemoglobin polymorphism observed in the populations under consideration. Evidence supporting the high migration model as the more realistic is also presented.

Asian Pacific countries that are particularly vulnerable to climate change recently endorsed the concept of an international public-private partnership to accelerate the application of greenhouse-benign energy such as renewables and efficiency measures. Rather than a global regulatory apparatus, this initiative seeks ultimately to stabilize greenhouse concentrations by speeding the time benign energy becomes cheaper than conventional fossil fuels. Such a South-North partnership could take many forms. These might include a dramatic reorientation of industrialized country investment in energy R&D to focus more on renewables and energy efficiency, public-private collaboration to enhance near-competitive renewable technologies, and the use of multilateral and bilateral development funds to spur private investment in such initiatives in developing countries.

Objective: To evaluate the effectiveness of the requirements of the voluntary safety standard for drawstrings on children's upper outerwear garments in preventing child deaths resulting from drawstring entanglement. Design: An interrupted time series design. Annual estimates of drawstring-related child deaths were developed for the study period of January 1985 to December 2009. A Poisson regression model for rate data was used to evaluate the effectiveness of the drawstring requirements during the postintervention period. Setting: United States. Subjects: Children aged 14 years and younger. Intervention: The application of the drawstring requirements of the voluntary standard that were adopted in 1997. Main Outcome Measure: The estimated percentage reduction in the drawstring-related child mortality rate associated with the application of the drawstring requirements. Results: The drawstring requirements of the voluntary standard were associated with a 90.9% (95% CI, 83.8%-96.1%) reduction in the drawstring-related mortality rate. This suggests the prevention of about 50 child deaths from 1997, when the voluntary standard was adopted, through the end of our study period in 2009. Conclusions: The requirements of the voluntary safety standard for drawstrings have been highly effective in preventing deaths resulting from the entanglement of drawstrings in children's upper outerwear garments.

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