The development of tissue surrogate materials that can replicate the mechanical response of biological soft tissues is of increasing interest. Such materials are required to enable robust experimental capabilities for evaluating next-generation armor systems that are critical to the survivability of the Soldier with regard to mechanical impact forces, including small caliber projectiles, fragme...

The use of laser-based optical techniques for medical imaging is an attractive alternative to other methods that utilize ionizing radiation. Beside being non-carcinogenic, it is non-invasive, the equipment is transportable, and the methodology can be used to examine properties of soft tissue. However, unlike x-ray photons, optical photons generated in the near-infrared suffer significant amount...

The material response discussed in the previous chapters was limited to the response of elastic materials, in particular to linearly elastic materials. Most metals, for example, exhibit linearly elastic behavior when they are subjected to relatively low stresses at room temperature. They undergo plastic deformations at high stress levels. For an elastic material, the relationship between stress...

A physical model describing the propagation of low-frequency surface waves in relation to the viscoelastic behavior of porcine skin is presented, along with a series of empirical studies testing the performance of the model. The model assumes that the skin behaves as a semi-infinite, locally isotropic, viscoelastic half-space. While the assumption of a semi-infinite body is violated, this viola...

Depletion of skeletal muscle mass in animals bearing an experimental model of cachexia, the MAC16 adenocarcinoma, occurs by a reduction in protein synthesis accompanied by a large increase in protein degradation. Serum from mice bearing the MAC16 tumour produced an increased protein degradation in isolated gastrocnemius muscle, as measured by tyrosine release, with a maximal effect occurring wi...

Introduction: Mechanical properties of human soft tissues can be investigated in vivo with dynamic magnetic resonance elastography (MRE) by applying low frequency shear waves and measuring the resulting tissue deflections [1]. From these data, elastic and viscoelastic modules are commonly calculated using the algebraic Helmholtz inversion [2,3]. So far, MRE is the only method for a noninvasive ...

During morphogenesis, forces generated by cells are coordinated and channeled by the viscoelastic properties of the embryo. Microtubules and F-actin are considered to be two of the most important structural elements within living cells accounting for both force production and mechanical stiffness. In this paper, we investigate the contribution of microtubules to the stiffness of converging and ...

Biomechanical properties are an excellent health marker of biological tissues, however they are challenging to be measured in-vivo. Non-invasive approaches to assess tissue biomechanics have been suggested, but there is a clear need for more accurate techniques for diagnosis, surgical guidance and treatment evaluation. Recently air-puff systems have been developed to study the dynamic tissue re...

A method to characterize the bulk hydrated properties of soft polymers and hydrogels, whose moduli are in the low MPa regime, using the pressure-bulge technique is presented. The pressure-bulge technique has been used extensively in the characterization of thin films, particularly for the case of metals. The extension of the plane-strain and circular bulge techniques to determine the Young’s mo...