Metachronal wave

Nonciliated cells separate fields of ciliated epithelial cells from each other. Synchronized ciliary movement, with a beat frequency in human proximal airways under normal conditions of 8-15 EIz, propels mucus along the mucociliary escalator at a rate of up to 25 mm/min. Beat frequencies appear to slow to roughly 7 Hz in more distal airways. Cilia move in the same direction and in phase within each field but cilia in adjacent fields move in slightly different directions and are phase shifted. These beat patterns result in metachronal waves that steadily move mucus at higher velocities ( -12-18 mm/min) than would be achievable by summing the motion of individual cilia. 

Metachronal wave Synchronized ciliary movement over a relatively large... 

Lagomarsino, M.C., Jona, P., and Bassetti, B. (2003) Metachronal waves for deterministic switching two-state oscillators with hydrodynamic interaction. Phys. Rev. E. 68, 021908-1-021908-9. 

Guirao, B. and Joatmy, J.-F. (2007) Spontaneous creation of macroscopic flow and metachronal waves in an array of dlia. Biophys. f, 92, 1900-1917. 

Niedermayer,T, Eckhardt, B., and Lenz, P. Synchronization, phase locking, and metachronal wave formation in ciliary chains. CHAOS. 18,037128-1-037128-10. 

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