We have investigated the force required to remove lumbar extradural catheters from 88 parturients to determine the effects of patient positioning at removal, relative to the position at insertion. Parturients were allocated randomly to one of four groups: LS (lateral insertion, sitting withdrawal), LL (lateral insertion, flexed lateral withdrawal), SL (sitting insertion, lateral withdrawal) or ...

In the permanent magnet linear synchronous motor (PMLSM), force ripple is harmful, useless and disturbing. The force ripple is basically composed of two components: detent force and mutual force ripple. This force is influenced by the geometric parameters of the permanent magnet (PM) motors; such as width, thickness and length of the magnet poles, length and thickness of the rotor and stato...

The lateral Casimir force between a sinusoidally corrugated gold coated plate and large sphere was measured for surface separations between 0.2 to 0.3 microm using an atomic force microscope. The measured force shows the required periodicity corresponding to the corrugations. It also exhibits the necessary inverse fourth power distance dependence. The obtained results are shown to be in good ag...

We present a study of the lateral resolution in electrostatic force microscopy for dielectric samples in both force and gradient modes. Whereas previous studies have reported expressions for metallic surfaces having potential heterogeneities (Kelvin probe force microscopy), in this work we take into account the presence of a dielectric medium. We introduce a definition of the lateral resolution...

Carbon nanotubes are usually imaged with the atomic force microscope (AFM) in non-contact mode. However, in many applications, such as mechanical manipulation or elasticity measurements, contact mode is used. The forces affecting the nanotube are then considerable and not fully understood. In this work lateral forces were measured during contact mode imaging with an AFM across a carbon nanotube...

A biomechanical study of lateral translation in lumbar spine with human cadavers was performed in order to explore the direction of the force increasing lateral translation and the contributions of discs and facet joints to lateral translation. Whole lumbar spines from 12 fresh cadavers were attached to a specially designed loading apparatus whose five cables simulated the muscles of the trunk ...