We measure kinematic coefficients of normal restitution in head-on collisions of two identical small spheres of acrylic, ceramic or steel suspended by thin resilient strands at low enough impact speeds for adhesion to lower the restitution. We observe such reduction at speeds consistent with an apparent adhesion surface energy larger than expected.

Combined experimental and theoretical developments have demonstrated that in addition to preexisting electrophysiological heterogeneities, cardiac electrical restitution properties contribute to breakup of reentrant wavefronts during cardiac fibrillation. Developing therapies that favorably alter electrical restitution properties have promise as a new paradigm for preventing fibrillation.

We present numerical simulations of surface waves in vibrated granular systems. For the simulations we use an event driven (ED) procedure with a non-constant restitution coeecient. The important advantage of a non-constant restitution coeecient is that it allows to circumvent the \inelastic collapse", i.e. the divergence of collision frequency, usually observed in ED simulations of dense and di...

Upon ligand binding, epidermal growth factor (EGF) receptor (R) autophosphorylates on COOH-terminal tyrosines, generating docking sites for signaling partners that stimulate proliferation, restitution, and chemotaxis. Specificity for individual EGFR tyrosines in cellular responses has been hypothesized but not well documented. Here we tested the requirement for particular tyrosines, and associa...

Spatial heterogeneity of repolarization can provide a substrate for reentry to occur in myocardium. This heterogeneity may result from spatial differences in action potential duration (APD) restitution. The restitution portrait (RP) measures many aspects of rate-dependent restitution: the dynamic restitution curve (RC), S1-S2 RC, and short-term memory response. We used the RP to characterize ep...

The spatial variation in restitution properties in relation to varying stimulus site is poorly defined. This study aimed to investigate the effect of varying stimulus site on apicobasal and transmural activation time (AT), action potential duration (APD) and repolarization time (RT) during restitution studies in the intact human heart. Ten patients with structurally normal hearts, undergoing cl...

Small bowel epithelium is at the frontline of intestinal barrier function. Restitution is considered to be the major determinant of epithelial repair, because function recovers in parallel with restitution after acute injury. As such, studies of intact mucosa have largely been replaced by migration assays of cultured epithelia. These latter studies fail to account for the simultaneous roles pla...

Early epithelial restitution is an important repair modality in the gut mucosa and occurs as a consequence of epithelial cell migration. Canonical transient receptor potential-1 (TRPC1) functions as a store-operated Ca2+ channel (SOCs) in intestinal epithelial cells (IECs) and regulates intestinal restitution, but the exact upstream signals initiating TRPC1 activation after mucosal injury remai...

BASS, kz G. htitution of the action potential in cat papillary muscle. Am. J. Physiol. Z%(6) : 17 17-l 724. 1975.-Membrane recovery (electrical restitution) following an action potential (AP) was studied in isolated, electrically driven cat papillary muscle by interpolation of test extrasystoles at various delays in the interval between two AP’s (recorded with glass microelectrodes). Curves des...

Action potential duration (APD) restitution, which relates APD to the preceding diastolic interval (DI), is a useful tool for predicting the onset of abnormal cardiac rhythms. However, it is known that different pacing protocols lead to different APD restitution curves (RCs). This phenomenon, known as APD rate dependence, is a consequence of memory in the tissue. In addition to APD restitution,...