one of the most common diseases associated with musculo-skeletal ailment is low back pain which is epidemic among general public. if manual tasks are performed inappropriately by workers at workplaces, it may cause back pain in the lumbar spine. in recent years, a variety of assistive devices has been presented and used to utilize a passive force generator which has been effective in decreasing...

Total knee replacement (TKR) is commonly used to correct end-stage knee osteoarthritis. Unfortunately, difficulty with stair climbing often persists and prolongs the challenges of TKR patents. Complete understanding of loading at the knee is of great interest in order to aid patient populations, implant manufacturers, rehabilitation, and future healthcare research. Musculoskeletal modeling and ...

We present a new method to locally apply mechanical tensile and compressive force on single cells based on integration of a microfluidic device with an optical laser tweezers. This system can locate a single cell within customized wells exposing a square-like membrane segment to a functionalized bead. Beads are coated with extracellular matrix (ECM) proteins of interest (e.g. fibronectin) to ac...

BACKGROUND The aim of the present work was to evaluate the stress magnitudes and directions along the midpalatal suture in the maxillary protraction therapy. METHODS The geometry of the maxilla and teeth were digitally reconstructed based on computer tomography images obtained from the skull of a girl in a mixed dentition stage with skeletal and dental class III malocclusion. An appliance com...

Interactions between cells and the surrounding matrix are critical to the development and engineering of tissues. We have investigated the role of cell-derived traction forces in the assembly of extracellular matrix using what we believe is a novel assay that allows for simultaneous measurement of traction forces and fibronectin fibril growth at discrete cell-matrix attachment sites. NIH3T3 cel...

Nearly all mechanochemical models of the cross-bridge treat myosin as a simple linear spring arranged parallel to the contractile filaments. These single-spring models cannot account for the radial force that muscle generates (orthogonal to the long axis of the myofilaments) or the effects of changes in filament lattice spacing. We describe a more complex myosin cross-bridge model that uses mul...

A polymer chain pinned in space exerts a fluctuating force on the pin point in thermal equilibrium. The average of such fluctuating force is well understood from statistical mechanics as an entropic force, but little is known about the underlying force distribution. Here, we introduce two phase space sampling methods that can produce the equilibrium distribution of instantaneous forces exerted ...

Abstract In this paper the generalized model of contact two plan bodies that roll and slide or just is presented. The analytical solution correct distribution pressure in realized presence normal compressive force, which realizes contact, as well force pair a tangential force. This can be used on sprocket teeth due to sliding rolling itself gear pole. results obtained have been experimentally c...

introduction: flow rate (fr) and compressive strength (cs) are important properties of endodontic biomaterials that may be affected by various mixing methods. the aim of this experimental study was to evaluate the effect of different mixing methods on these properties of mineral trioxide aggregate (mta) and calcium-enriched mixture (cem) cement. materials and methods: hand, amalgamator and ultr...