12 research outputs found
Upregulation of jasmonate biosynthesis and jasmonate-responsive genes in rice leaves in response to a bacterial pathogen mimic
Comparison of two laryngeal tissue fiber constitutive models
[[abstract]]Biological tissues are complex time-dependent materials, and the best choice of the appropriate time-dependent constitutive description is not evident. This report reviews two constitutive models (a modified Kelvin model and a two-network OgdenâBoyce model) in the characterization of the passive stressâstrain properties of laryngeal tissue under tensile deformation. The two models are compared, as are the automated methods for parameterization of tissue stressâstrain data (a brute force vs. a common optimization method). Sensitivity (error curves) of parameters from both models and the optimized parameter set are calculated and contrast by optimizing to the same tissue stressâstrain data. Both models adequately characterized empirical stressâstrain datasets and could be used to recreate a good likeness of the data. Nevertheless, parameters in both models were sensitive to measurement errors or uncertainties in stressâstrain, which would greatly hinder the confidence in those parameters. The modified Kelvin model emerges as a potential better choice for phonation models which use a tissue model as one component, or for general comparisons of the mechanical properties of one type of tissue to another (e.g., axial stress nonlinearity). In contrast, the OgdenâBoyce model would be more appropriate to provide a basic understanding of the tissueâs mechanical response with better insights into the tissueâs physical characteristics in terms of standard engineering metrics such as shear modulus and viscosity