Geckos owe their remarkable stickiness to millions of dry, hard setae on their toes. In this study, we discovered that gecko setae stick more strongly the faster they slide, and do not wear out after 30,000 cycles. This is surprising because friction between dry, hard, macroscopic materials typically decreases at the onset of sliding, and as velocity increases, friction continues to decrease be...

We study the stability of steady sliding between elastically deformable continua using rate and state dependent friction laws. That is done for both elastically identical and elastically dissimilar solids. The focus is on linearized response to perturbations of steady state sliding, and on studying how the positive direct effect (instantaneous increase or decrease of shear strength in response ...

Lubrication is essential to minimize wear and friction between contacting surfaces in relative motion. Oil based lubricants are often enhanced via polymer additives self-degradation due the shear thinning effect. Therefore, an accurate estimate of load carrying capacity thin lubricating film requires careful modeling thinning. Available models such as generalized Reynolds equation (GR) approxim...

Reciprocating contacts occur in a wide variety of practical wear situations including hip joints and electrical contacts. In developing tribological tests for candidate materials with improved durability these it is beneficial that the contact conditions (e.g. sliding speed) can be reproduced. Hence, fully instrumented capability rapid high-cycle linear reciprocating nano-scale has been develop...

While frictionless spheres at jamming are isostatic, frictional spheres at jamming are not. As a result, frictional spheres near jamming do not necessarily exhibit an excess of soft modes. However, a generalized form of isostaticity can be introduced if fully mobilized contacts at the Coulomb friction threshold are considered as slipping contacts. We show here that, in this framework, the vibra...

Sense of coherence (SOC), with its components comprehensibility, manageability, and meaningfulness, is a major factor in the ability to cope successfully with stressors and is closely related to health. Qualitative studies related to SOC are scarce, and in this phenomenological interview study, self-care is investigated in relation to SOC. The aim of this study was to describe the lived experie...