Figure 4.

Experimental data (circles) showing the hysteresis and transmural-pressure dependence of lymphatic valve function, from Davis et al. (2011), and the fitted curves (solid lines) that were used in the lymphangion model. Note the change in definition of the transmural pressure on the abscissa between the two panels. The dotted curve shows the suggested closing threshold explained later in the paper (section 4). Variables here conform to those of Davis et al. (2011); their P_ext is p_e in this paper, while P_in is p_i–1,2 and P_out is p_i1.