2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/58545We study the conditions on the physical parameters in the Helfrich bending energy of lipid bilayer vesicles. Among embedded surfaces with a biconcave axisymmetric shape, the variation equation is analyzed in detail. This leads to simple conditions which guarantee the solution the information about the geometry.23 pages, 1 figure, AMSLaTeX, major revision of "On the existence of biconcave shape vesicles". No offset problemAnalysis of PDEstext