We introduce a model of proportional growth to explain the distribution Pg(g) of business-firm growth rates. The model predicts that Pg(g) is exponential in the central part and depicts an asymptotic power-law behavior in the tails with an exponent z=3. Because of data limitations, previous...

Wildfires, suspended soil and other particulates, and industrial emissions combine to raise the urgency of air quality as a planetary threat. This paper introduces Prometheus, a proactive decision-making framework for managing environmental and health risks associated with air pollution and...