The planar plasma membrane model with linear polymer spacers with defined lengths enables the control of the frictional coupling between incorporated transmembrane proteins (human platelet integrin) and the solid substrate. This mimics the viscous environment provided by the extracellular matrix of cells. The friction coefficient can be calculated quantitatively from the diffusion coefficient o...

The effect of C60 molecular rotation on the nanotribological properties of C60 single crystal surfaces has been studied by atomic/frictional force microscopy. The orientational order-disorder phase transition, in which the high temperature C60 free rotation is reduced to a low temperature hindered rotation, is shown to give rise to an abrupt change in friction and adhesion. This change in frict...

The physicochemical properties of bovine prothrombin and of bovine thrombin were previously described in this journal (1, 2). A derivative of bovine prothrombin, autoprothrombin II, has now been obtained in sufficient quality and quantity for study. In this report we describe some of the physicochemical properties of our product, including sedimentation coefficient, diffusion coefficient, intri...

OBJECTIVE To compare frictional properties according to the amounts of vertical displacement (VD) and horizontal displacement (HD) of teeth and bracket types during the initial leveling/alignment stage. METHODS Combinations of self-ligating brackets (SLBs; two active type: In-Ovation-R and In-Ovation-C; four passive type: Damon-3Mx, Damon-Q, SmartClip-SL3, and Clarity-SL) and 0.014-inch nicke...

We study the coherence of transport of an overdamped Brownian particle in frictional ratchet system in the presence of external Gaussian white noise fluctuations. The analytical expressions for the particle velocity and diffusion coefficient are derived for this system and the reliability or coherence of transport is analysed by means of their ratio in terms of a dimensionless Péclet number. We...

The physical properties of bovine prothrombin preparations have been described in this journal (1). Although methods for obtaining bovine thrombin are now also available (a), the physical properties, including the molecular weight, have not been described. Here we report values for the sedimentation coefficient, diffusion coefficient, intrinsic viscosity, frictional ratio, molecular weight, and...