Fig. 1From: Short-term exposure to PM2.5 and vanadium and changes in asthma gene DNA methylation and lung function decrements among urban childrenStudy design. Residential indoor monitoring, pulmonary lung function test, and buccal sample collection over a 6Â day sampling period, repeated 6Â months later, are displayed. a Time 1 (March 2012 and August 2015). b Time 2: Repeated 6Â months laterBack to article page