Fig. 1.

(A) Molecular structure of human aquaporin 4 (hAQP4) obtained from the Protein Data Bank (28). (B) Profiles of two aquaporins collected from ref. 13. Pore dimensions were estimated using the HOLE program (29). (C) Biconical channel considered in this work. The central cylinder, where perfect slip is assumed, is connected to two truncated cones of length L, opening angle α, and with perfect or finite slip (slip length b; see text). (D) Schematic of the system used for the FE resolution of the Stokes equation (COMSOL). The channel is connected to half-spherical reservoirs (not to scale). Color represents the magnitude of fluid velocity, from blue (slow flow) to red (fast flow).