Figure 15.

Results of plug passages and ruptures over the airway cells. Red cells are dead and green are alive. (a) Single-phase liquid flows do not damage differentiated cells. Exposure to propagation and subsequent rupture of liquid plugs results in progressively larger numbers of injured cells [(b)–(d)]. PR is plug propagation and ruptures within 10 min. (e) The extent of cellular damage is elevated with increasing PR. (f) Numerical simulation reveals generated large wall shear and wall pressure gradients. (g) Downstream viability suggests more deleterious mechanical stresses at site of plug rupture. Reprinted with permission from D. Huh, H. Fujioka, Y. C. Tung, N. Futai, R. Paine, J. B. Grotberg, and S. Takayama, Proc. Natl. Acad. Sci. U.S.A. 104, 18886 (2007). Copyright 2007, National Academy of Sciences, U.S.A.