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Particle distributions of different sub-cases: (a) sub-case 1, (b) sub-case 2, (c) sub-case 3, (d) sub-case 4, (e) sub-case 5, (f) sub-case 6, (g) sub-case 7, and (h) sub-case 8. (Red particles were those from the previous sub-case and the blue particles were newly generated by the index person through breathing for the next sub-case.). (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)
