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Association curve for 3-year average PM2·5 and mortality under different tertiles of contemporaneous NDVI
(A) Tertile 1 of contemporaneous NDVI. (B) Tertile 2 of contemporaneous NDVI. (C) Tertile 3 of contemporaneous NDVI. HR=hazard ratio. NDVI=normalised difference vegetation index. PM2·5=fine particulate matter.
