Fig. 4.

Multiscale model based on aortic media structure. (a) Hematoxylin and eosin stain shows smooth muscle cell nuclei (dark purple) and elastic lamina (pink). (b) Masson's trichrome stain shows collagen (blue) within the lamina and smooth muscle (red). (c) Verhoeff–Van Gieson shows elastin (black/purple). (d) A microstructural model based on the histology contains a layer of elastin (red) reinforced by collagen fibers (black). The collagen fibers are aligned preferentially in the circumferential direction, and the elastin sheet is isotropic. Lamellae are connected by interlamellar connections (green) representing the combined contribution of fibrillin and smooth muscle. The interlamellar connections are aligned primarily in the radial direction but also have some preference for circumferential alignment to match smooth muscle alignment in vivo. (e) An RVE with eight gauss points. (f) FE geometry showing a uniaxial shaped sample (equibiaxial, lap, and peel geometries were also used).