Narrow Results

This study intends to evaluate the ratcheting response of biological samples prepared from bovine and porcine trabecular bone, articular cartilage, meniscus, and skin tissues and tested under asymmetric (nonzero mean stress) cycles. Meniscus and skin samples were tested with stress ratios of $R=0.1$ and $R=0.6$, respectively, while other tissues were tested at $R=0$. Experimental ratcheting data and related influential parameters including stress level, stress rate, and testing frequency were discussed. A parametric ratcheting equation was further calibrated to estimate the ratcheting response of tissues. The predicted ratcheting data were found to be in close agreement with the reported experimental data.

A mathematical model based on Pennes bio-heat equation was formulated to estimate temperature profiles at peripheral regions of human body. The heat processes due to diffusion, perfusion and metabolic pathways were considered to establish the second-order partial differential equation together with initial and boundary conditions. The model was solved using eigenvalue method and the numerical values of the physiological parameters were used to understand the thermal disturbance on the biological tissues. The results were illustrated at atmospheric temperatures $T_A=10^{\circ }$C and $20^{\circ }$C.

We propose and conduct both the rotating linear polarization imaging (RLPI) and Mueller matrix transformation (MMT) measurements of different biological tissue samples, and testify the capability of the Mueller matrix polarimetry for the anisotropic scattering media. The independent parameters extracted from the RLPI and MMT techniques are compared and analyzed. The tissue experimental results show that the parameters are closely related to the structural characteristics of the turbid scattering media, including the sizes of the scatterers, the angular distribution and order of alignment of the fibers. The results and conclusions in this paper may provide a potential method for the detection of precancerous and early stage cancerous tissues. Also, such studies represent the Mueller matrix transformation procedure which results in a set of parameters linking up the Mueller matrix elements to the structural and optical properties of the media.