Fig. 2From: Effects of particulate matter (PM) on childhood asthma exacerbation and control in Xiamen, ChinaDistribution and exposure leveltoPM2.5. Panel(a): Distribution of exposure days of PM2.5 in one week before the exacerbation and the density curve;Panel(b): Distribution of exposure days of PM2.5 in two weeks before the exacerbation and the density curve; Panel(c): Exposure days of PM2.5 in one week (red line) and in two weeks (blue line) before the exacerbationBack to article page