UNLABELLED Stride length analysis represents an easy method for assessing race walking kinematics. However, the stride parameters emerging from such an analysis have never been used to design a training protocol aimed at increasing stride length. With this aim, we investigated the effects of stride frequency manipulation during three weeks of uphill (2%) training on stride length at iso-efficie...

Surfaces can be slippery or sticky depending on surface chemistry and roughness. We demonstrate in atomistic simulations that regular and random slip patterns on a surface lead to pressure excursions within a lubricated contact that increase quadratically with decreasing contact separation. This is captured well by a simple hydrodynamic model including wall slip. We predict with this model that...

The profiles of a spreading wetting film are computed taking into account intermolecular forces and introducing a kinetic slip condition at a molecular cut-off distance. This eliminates the stress singularity, so that both “true” and “visible” contact angles are defined unequivocally. The “true” contact angle at the cut-off distance depends on the slip length as well as on the edge propagation ...

Pinning of a solid–liquid–vapour interface by stripes of obstacles. Abstract We use a macroscopic Hamiltonian approach to study the pinning of a solid–liquid–vapour contact line on an array of equidistant stripes of obstacles perpendicular to the liquid. We propose an estimate of the density of pinning stripes for which collective pinning of the contact line happens. This estimate is shown to b...

A set of simple time to contact estimators are derived, using isolated points or curve segments. For this purpose the use of both optic ow and optic acceleration is suggested. For curves it is pointed out, that there is no aperture problem present, since normal ow and acceleration of the curve segment is suucient for estimating time to contact. Time to contact with a curve segment may be calcul...

Molecular dynamics simulations reveal that thermal-induced edge barriers and forces can govern the interlayer interaction of double walled carbon nanotubes. As a result, friction in such systems depends on both the area of contact and the length of the contact edges. The latter effect is negligible in macroscopic friction and provides a feasible explanation for the seemingly contradictory laws ...

Abstract. In this paper, we set up the dynamic frictionless Euler Bernoulli equation with Signorini contact conditions along the length of a thin beam and consider how to solve this equation. The existence of solutions is shown, based on a penalty method. Using energy conservation in the penalty method, we bound the integral of contact forces over time and space. Hölder continuity of the fundam...

BACKGROUND A description is given of a major outbreak of isoniazid monoresistant tuberculosis (TB) chiefly in north London, including prisons. The earliest case was diagnosed in 1995 with most cases appearing after 1999. METHODS Confirmation of a local cluster of cases was confirmed by restriction fragment length polymorphism (RFLP IS6110) typing or "rapid epidemiological typing" (RAPET). Fur...

BACKGROUND In recent years several population based studies using restriction fragment length polymorphism (RFLP) analysis have shown a higher rate of recent transmission of tuberculosis than previously thought. This study was undertaken to determine the transmission patterns of tuberculosis and the potential causes of recent transmission on the island of Gran Canaria (Spain). METHODS The str...

We present performance characteristics of nanoscaled cobalt phthalocyanine-based organic field-effect transistors (OFETs) as a function of channel length. We found a channel length range which maximizes the field effect mobility in a trade-off between the decrease in the number of organic grain boundaries and the increase of the electrode-organic contact region. Further reduction of channel len...