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This study aims to develop a viscoelastic database for muscles (VM: vastus medialis and Sr: sartorius) and subcutaneous adipose tissue with multifrequency magnetic resonance elastography (MMRE) coupled with rheological models. MMRE was performed on 13 subjects, at 70-90-110 Hz, to experimentally assess the elastic properties (μ) of passive and active (20% MVC) muscles. Then, numerical shear modulus (μ) and viscosity (η) were calculated using three rheological models (Voigt, Zener, Springpot). The elastic properties, obtained with the Springpot model, were closer to the experimental data for the different physiological tissues (μ_{Springpot_VM_Passive} = 3.67 ± 0.71 kPa, μ_{Springpot_Sr} = 6.89 ± 1.27 kPa, μ_{Springpot_Adipose Tissue} = 1.61 ± 0.37 kPa) and at different muscle states (μ_{Springpot_VM_20%MVC} = 11.29 ± 1.04 kPa). The viscosity parameter increased with the level of contraction (η_{_VM_Passive_Springpot} = 4.5 ± 1.64 Pa.s versus η_{_VM_20%MVC_Springpot} = 12.14 ± 1.47 Pa.s) and varied with the type of muscle. (η_{_VM_Passive_Springpot} = 4.5 ± 1.64 Pa.s versus η_{_Sr_Springpot} = 6.63 ± 1.27 Pa.s). Similar viscosities were calculated for all tissues and rheological models. These first physiologically realistic viscoelastic parameters could be used by the physicians to better identify and monitor the effects of muscle disorder, and as a database for musculoskeletal model.

The traveling wave is the most important phenomenon in cochlear macromechanics. The behaviors of the traveling wave that greatly alter the auditory discrimination, are tightly related with the mechanical properties of the basilar membrane (BM) and its surrounding lymph. As an addition to the blanks of related researches, this paper focuses on some of the key parameters that affect the cochlear response most: the BM stiffness, damping parameters and the fluid viscosity. The influence of these parameters on the traveling wave is discussed, based on our former developed 2D finite element hydrodynamic cochlear model. Moreover, the traveling wave velocity and its transmitting time are calculated based on the simulating results. Although generally a rapid fall of the velocity from the cochlear base to the characteristic frequency (CF) location is confirmed, our quantitative analysis also indicates the traveling wave velocity may be both location and frequency dependent.