Open Access
EDITORIAL
Open Access
ARTICLE
V. Sansalone1,∗, V. Bousson2, S. Naili1, C. Bergot2, F. Peyrin3, J.D. Laredo2, G. Haïat1
CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.5, pp. 387-410, 2012, DOI:10.3970/cmes.2012.087.387
Abstract This paper investigates the effects of the heterogeneous distribution of the Haversian Porosity (HP) and Tissue Mineral Density (TMD) on the elastic coefficients of bone in the human femoral neck. A bone specimen from the inferior femoral neck was obtained from a patient undergoing standard hemiarthroplasty. The specimen was imaged using 3-D synchrotron micro-computed tomography (voxel size of 10.13 mm), leading to the determination of the anatomical distributions of HP and TMD. These experimental data were used to estimate the elastic coefficients of the bone using a three-step homogenization model based on continuum micromechanics: (i) At the tissue scale (characteristic… More >
Open Access
ARTICLE
J.A. García1,2, J.M. Peña1, S. McHugh2, A. Jérusalem2,3
CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.5, pp. 411-432, 2012, DOI:10.3970/cmes.2012.087.411
Abstract Neuronal growth is a complex process involving many intra- and extracellular mechanisms which are collaborating conjointly to participate to the development of the nervous system. More particularly, the early neocortical development involves the creation of a multilayered structure constituted by neuronal growth (driven by axonal or dendritic guidance cues) as well as cell migration. The underlying mechanisms of such structural lamination not only implies important biochemical changes at the intracellular level through axonal microtubule (de)polymerization and growth cone advance, but also through the directly dependent stress/stretch coupling mechanisms driving them. Efforts have recently focused on modeling approaches aimed at accounting… More >
Open Access
ARTICLE
Taffetani M.1, Bertarelli E.1,2, Gottardi R.3,4, Raiteri R.5, Vena P.1,2
CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.5, pp. 433-460, 2012, DOI:10.3970/cmes.2012.087.433
Abstract Dynamic nanoindentation is a novel nanomechanical testing that is being increasingly used to characterize the frequency response of viscoelastic materials and of soft hydrated biological tissues at the micrometric and nanometric length scales. This technique is able to provide more information than those obtained by simple indentation; however, its interpretation is still an open issue for complex materials such as the case of anisotropic biological tissues that generally have a high water content. This work presents a numerical model to characterize the frequency response of poro-elastic tissues subjected to harmonic indentation loading with particular regard to the effect of geometrical… More >
Open Access
ARTICLE
F. Maceri1, M. Marino1, G. Vairo1
CMES-Computer Modeling in Engineering & Sciences, Vol.87, No.5, pp. 461-482, 2012, DOI:10.3970/cmes.2012.087.461
Abstract The mechanical behavior of biopolymer mo -le -cu -les is herein addressed and a novel predictive model for their elasto-damage response is proposed. Both entropic and energetic elastic mechanisms are accounted for, and coupled by consistent equilibrium conditions. Moreover, through non-smooth mechanics arguments, molecular damage is modeled accounting for failure due to both mechanical and non-mechanical damage sources. The model is applied to collagen molecules and an excellent agreement with available experimental tests and atomistic computations is shown. The proposed predictive theory can be usefully integrated in hierarchical models of biological structures towards a multiscale continuum approach. More >