This study analyses the reaction forces and variations of rock climbing in vertical and overhanging positions. Subjects voluntarily released their right foot and regained equilibrium. In the overhanging position the quadrupedal state was characterised by a significant involvement of the arms to prevent fall. Moreover, the horizontal forces applied to the holds were less important, which suggest...

The paper presents a DEM model for simulating dry granular avalanche down an incline. Flow pattern and impact forces on rigid obstacles are considered. Results of the simulations are compared with experimental data reported in the literature. The experiments include granular flow along an inclined channel and three-dimensional free surface flow on an inclined chute merging into a horizontal run...

This paper describes the modification and instrumentation of standard parallel bars to allow for the measurement of applied forces on both horizontal bars in three dimensions. This measurement system has been used in the development and evaluation of functional electrical stimulation (FES) devices for standing and gait restoration in paralyzed patients. Real-time measurement of forces applied b...

Remarkable similarities in the vertical plane of forward motion exist among diverse legged runners. The effect of differences in posture may be reflected instead in maneuverability occurring in the horizontal plane. The maneuver we selected was turning during rapid running by the cockroach Blaberus discoidalis, a sprawled-postured arthropod. Executing a turn successfully involves at least two r...

The determination and analysis of complete genome sequences has led to the suggestion that horizontal gene transfer may be much more extensive than previously appreciated. Many of these studies, however, rely on evidence that could be generated by forces other than gene transfer including selection, variable evolutionary rates, and biased sampling.

The stationary problem for the heat convection of compressible fluid is considered around the equilibrium solution with the external forces in the horizontal strip domain z0 < z < z0 + 1 and it is proved that the solution exists uniformly with respect to z0 ≥ Z0 . The limit system as z0 → +∞ is the Oberbeck-Boussinesq equations. Mathematics Subject Classification (2010). Primary 35Q35; Secondar...

Falls are a leading cause of occupational injuries and fatalities. A substantial proportion of occupational falls results from loss of postural stability. Load lifting perturbs postural stability, and thus is often associated with an increased incidence of falls. Although aged people are at higher fall risks, few studies have examined age effects on postural stability during lifting. Therefore,...

We study by Monte Carlo simulation the compaction dynamics of hard dimers in two dimensions under the action of gravity, subjected to vertical and horizontal shaking, considering also the case in which a friction force acts for horizontal displacements of the dimers. These forces are modeled by introducing effective probabilities for all kinds of moves of the particles. We analyze the dynamics ...

The function of the heterocercal tail in sharks has long been debated in the literature. Previous kinematic data have supported the classical theory which proposes that the beating of the heterocercal caudal fin during steady horizontal locomotion pushes posteroventrally on the water, generating a reactive force directed anterodorsally and causing rotation around the center of mass. An alternat...

We present results from an independent analysis of friction that more generally addresses all crystalline materials by an extension of coincident site lattice theory and dislocation drag. Calculations for graphitic friction are carried out and agree in magnitude with experimental friction forces. More interestingly, static, dynamic and anisotropic friction forces, incommensurability effects and...