Experiments in which two specifically interacting protein molecules are dissociated by external force have yielded new insights into mechanisms involved in cell adhesion, leukocyte rolling, regulation of integrin activity, antigen-antibody interactions and other protein-mediated reactions contingent upon molecular recognition. Another important aspect of force-induced protein-protein unbinding ...

A microcantilever technique was used to apply force to receptor-ligand molecules involved in leukocyte rolling on blood vessel walls. E-selectin was adsorbed onto 3-microm-diameter, 4-mm-long glass fibers, and the selectin ligand, sialyl Lewis(x), was coupled to latex microspheres. After binding, the microsphere and bound fiber were retracted using a computerized loading protocol that combines ...

Rolling processes for which the characteristic length scale reaches into the range where size effects become important are receiving increased interest. In particularly, this is owed to the roll-molding process under development for high-throughput of micronscale surface features. The study presented revolves around the rolling induced effect of visco-plasticity (ranging hot and cold rolling) i...

This paper shows the mixed lubrication analysis between the vane tip and rolling piston in a rotary refrigerant compressor, coupling the motion equations of vane and rolling piston, the elastohydrodynamic lubrication (EHL) analysis of line contact and the equations of viscosity characteristics of lubricating oil as a function of oil pressure, oil temperature and concentration of refrigerant. Th...

A number of problems of dynamic deformation in the presence of moving contact surfaces are considered. A grid characteristic method using a two-dimensional irregular triangular grid and a hybrid scheme with 1-2 order of approximation is adapted. An algorithm for calculating the force of friction and the force of static friction is proposed. The numerical solution to wheel rolling and shear wave...

This work is about designing Pobot V2, a robot capable to climb poles with a cylindrical or conical shape. It is original because of its rolling self-locking concept: rolling allows continuous ascension whereas self-locking guarantees a null energy consumption while staying still on the pole. The robot is also capable to avoid tangential obstacles, to cross small collars and to regulate passive...

Using contact dynamics simulations, we compare the effect of rolling resistance at the contacts in granular systems composed of disks with the effect of angularity in granular systems composed of regular polygonal particles. In simple shear conditions, we consider four aspects of the mechanical behavior of these systems in the steady state: shear strength, solid fraction, force and fabric aniso...

Steel making is known as a complex manufacturing industrial process. Automation of the process represents a challenge. Empirical mathematical modeling of the process was used to design mill equipment, ensure productivity and service quality. This modeling approach shows many problems associated to complexity and time consumption. Soft computing techniques show significant modeling capabilities ...

The rolling/sliding in the presence of friction of a vibrating elastic body on an elastic substrate is studied. It is shown that the longitudinal components of the velocity of the center of mass of the body and of the resultant frictional force are not affected by the vibration process. However, the normal vibration of the body influences the slip velocities and the distribution of frictional f...

The purpose of this study was to describe a rolling motion, which is common in normal adults and patients with motor disorder, and to try to understand the mechanism of the motion. Ten healthy young adults participated in the experiment and were requested to roll from supine to side-lying by pressing the floor with their contra-lateral foot. Their motions in the task were measured with a 3-D an...