Muscle contraction and many other cell movements are driven by cyclic interactions between actin filaments and the motor enzyme myosin. Conformational changes in the actin-myosin binding interface occur in concert with the binding of ATP, binding to actin, and loss of hydrolytic by-products, but the effects of these conformational changes on the strength of the actomyosin bond are unknown. The ...

High servo control response and high energy-efficiency are requested in hydraulic servo systems of current hydraulic machines. This investigation concurrently implements energy-saving control and velocity-force control for simultaneously realizing high velocity-force control response and high energy-efficiency for hydraulic valve-controlled cylinder systems. The velocity-force control of the hy...

BACKGROUND The purpose of this study was to determine the relative amount of load that is transmitted through the superior portion of the subscapularis during activities of daily living as compared with the load that is transmitted through the middle and inferior portions in a normal shoulder and in a shoulder with a supraspinatus tear. METHODS By use of the Newcastle shoulder model, the subs...

Skeletal muscle's ability to shorten and lengthen against a load is a fundamental property, presumably reflecting the inherent load-dependence of the myosin molecular motor. Here we report the velocity of a single actin filament translocated by a mini-ensemble of skeletal myosin approximately 8 heads under constant loads up to 15 pN in a laser trap assay. Actin filament velocity decreased with ...

In the human spine, it is well known that facet joints play a significant role in load transmission and providing stability. It has also been hypothesized to be one of most probable sources of low back pain. Experimental determination of the load-bearing role of lumbar intervertebral joints, such as the facets joints, under axial compression has not been a straightforward task. In this study, t...

Previous studies on adaptation of fingertip forces to local friction at individual digit-object interfaces largely focused on static phases of manipulative tasks in which humans could rely on anticipatory control based on the friction in previous trials. Here we instead analyze mechanisms underlying this adaptation after unpredictable changes in local friction between consecutive trials. With t...

Mechanosensitive biological nanomachines such as motor proteins and ion channels regulate diverse cellular behaviour. Combined optical trapping with single-molecule fluorescence imaging provides a powerful methodology to clearly characterize the mechanoresponse, structural dynamics and stability of such nanomachines. However, this system requires complicated experimental geometry, preparation a...

BACKGROUND The total contact cast (TCC) is an effective intervention to reduce plantar pressure in patients with diabetes and a plantar forefoot ulcer. The walls of the TCC have been indirectly shown to bear approximately 30 % of the plantar load. A new direct method to measure inside the TCC walls with capacitance sensors has shown that the anterodistal and posterolateral-distal regions of the...

Purpose – The purpose of this paper is to present an analysis of the force ripples of an open slot permanent magnet linear synchronous motor (PMLSM). A calculation procedure using 2D finite elements method is then evaluated with experimentations. Design/methodology/approach – First, the studied PMSLM and its main features are introduced. Then, we present the 2D-FEM model used to study the motor...

Friction and wear become significant at small scale lengths, particularly in MEMS/NEMS. Nanopatterns are regarded as a potential approach to solve these problems. In this paper, we investigated the friction behavior of nanopatterned silicon surfaces with a periodical rectangular groove array in dry and wear-less single-asperity contact at the nanoscale using molecular dynamics simulations. The ...