Fig. 4

Endfoot area and gap area fraction from Voronoi tessellations. (First row) endfoot area distribution (left) and resulting gap area fraction (right) for 200 realizations with \(r_{\textrm{o}} = 2.9\,\upmu \hbox {m}^{2}\) (capillary), (second row) \(r_{\textrm{o}} = 15.0\,\upmu \hbox {m}^{2}\) (venule), (third row) \(r_{\textrm{o}} = 15.0\,\upmu \hbox {m}^{2}\) (arteriole). The dashed vertical line marks the mean (capillary: \(A=50\,\upmu \hbox {m}^{2}\), \(\bar{\phi }^A_{\textrm{g}} = 0.0056\); venule: \(A=110\,\upmu \hbox {m}^{2}\), \(\bar{\phi }^V_{\textrm{g}} = 0.0038\); arteriole: \(A=490\,\upmu \hbox {m}^{2}\), \(\bar{\phi }^A_{\textrm{g}} = 0.0018\)). The quantity ’gaps/ring’ states the number of inter-cellular endfoot gaps, on average, on cross-sectional vessel cuts. The resulting gap area fraction—if this value were to be extrapolated to the total surface—is denoted by \(\phi ^\perp _{\textrm{g}}\). ’Gaps/ring’ and \(\phi ^\perp _{\textrm{g}}\) are reported for comparison with experimental data. The solid lines represent fitted continuous distributions using a Gamma distribution for the endfoot area and a normal distribution for the gap area fraction