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Changes in lipid layer structure as a function of short (0.01–0.14 s), medium (3.00–3.57 s) and long (10.20–19.53 s) times after a blink. (a) “Backgrounds” graded as “sea”=1, “irregular”=0. Numbers in parentheses are the number of sea grades observed in 50 images. (b) Grades of density and size of “droplets” on a scale of 0 (absent or rare) to 4 (dense).
