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Composite figure composed of stills from high-speed videography of schlieren imaging of a cough from a healthy volunteer lying on operating table with head within a barrier enclosure. (a) Still image immediately before cough with further images taken in series at (b) 5%, (c) 10%, (d) 40%, and (e) 75% of total cough duration, and (f) immediately upon cessation of air expiration as air continues to move around and out of the box.
