BACKGROUND Osteochondral autograft transfer (OAT) aims at restoring normal articular cartilage surface geometry and articular contact mechanics. To date, no studies have evaluated the contact mechanics of the canine stifle following OAT. Additionally, there are no studies that evaluated the role of the meniscus in contact mechanics following OAT in human or canine femorotibial joints. The objec...

Biological adhesive contacts are usually of hierarchical structures, such as the clustering of hundreds of sub-micrometre spatulae on keratinous hairs of gecko feet, or the clustering of molecular bonds into focal contacts in cell adhesion. When separating these interfaces, releasable adhesion can be accomplished by asymmetric alignment of the lowest scale discrete bonds (such as the inclined s...

This article develops a general framework for applying algebraic multigrid techniques to constrained systems of linear algebraic equations that arise in applications with discretized PDEs. We discuss constraint coarsening strategies for constructing multigrid coarse grid spaces and several classes of multigrid smoothers for these systems. The potential of these techniques is investigated with t...

We characterize the lengthscale-dependent rheological properties of mucus from the ubiquitous Chaetopterus marine worm. We use optically trapped probes (2-10 μm) to induce microscopic strains and measure the stress response as a function of oscillation amplitude. Our results show that viscoelastic properties are highly dependent on strain scale (l), indicating three distinct lengthscale-depende...

Thermally-assisted compaction of granular materials is of keen interest in many engineering applications. A proper estimation of the material behavior of compacted granular materials is contingent upon the knowledge of microstructure formation, which is highly dependent on the bulk material properties and processing conditions, during the deformation stage. Originating from the pair interaction...

Recent advances in contact mechanics have formalized approaches to distinguish between poroelastic and viscoelastic deformation regimes via load relaxation experiments, and to simultaneously extract the mechanical and transport properties of gels at the macroscale. As poroelastic relaxation times scale quadratically with contact diameter, contact radii and depths on the mm scale can require hou...

We start with a mathematical model which describes the frictionless contact of an elastic body obstacle and prove that it leads to stationary inclusion for strain field. Then, inspired by this model, we consider general in real Hilbert space, governed three parameters. unique solvability as well continuous dependence its solution respect use these results study associated optimal control proble...