Yao Jiang, Varner Victor D, Brilli Lauren L, Young Jonathan M, Taber Larry A, Perucchio Renato
Department of Mechanical Engineering, University of Rochester, Rochester, NY 14627, USA.
J Biomech Eng. 2012 Feb;134(2):024502. doi: 10.1115/1.4005693.
Accurate material properties of developing embryonic tissues are a crucial factor in studies of the mechanics of morphogenesis. In the present work, we characterize the viscoelastic material properties of the looping heart tube in the chick embryo through nonlinear finite element modeling and microindentation experiments. Both hysteresis and ramp-hold experiments were performed on the intact heart and isolated cardiac jelly (extracellular matrix). An inverse computational method was used to determine the constitutive relations for the myocardium and cardiac jelly. With both layers assumed to be quasilinear viscoelastic, material coefficients for an Ogden type strain-energy density function combined with Prony series of two terms or less were determined by fitting numerical results from a simplified model of a heart segment to experimental data. The experimental and modeling techniques can be applied generally for determining viscoelastic material properties of embryonic tissues.
发育中的胚胎组织的精确材料特性是形态发生力学研究中的关键因素。在本研究中，我们通过非线性有限元建模和微压痕实验来表征鸡胚中环状心管的粘弹性材料特性。对完整心脏和分离的心肌凝胶（细胞外基质）进行了滞后和斜坡保持实验。采用逆计算方法确定心肌和心肌凝胶的本构关系。假设两层均为准线性粘弹性，通过将心脏节段简化模型的数值结果与实验数据拟合，确定了与两项或更少项的Prony级数相结合的Ogden型应变能密度函数的材料系数。实验和建模技术可普遍应用于确定胚胎组织的粘弹性材料特性。
