Publications by authors named "W Stille"

The deformation of cholesteric elastomers by mechanical stress applied parallel to the helix axis is studied by calculation of the free-energy density. The Frank-elasticity contribution is taken into account. A chiral solvent, present at cross-linking time, is in general considered to be replaced after cross-linking by a solvent with different chirality.

View Article and Find Full Text PDF

The effect of Frank elasticity on deformations of cholesteric elastomers by mechanical stress applied perpendicular to the helix axis is studied by numerical minimization of the free energy. Above a critical strain, a solution with an only oscillating director is found to be stable in comparison to a distorted helix. At the critical strain, the contractions perpendicular to stress change discontinuously.

View Article and Find Full Text PDF

Background: Infection with Chlamydia pneumoniae may be involved in atherosclerosis. Neointima proliferation after percutaneous coronary intervention (PCI) could be aggravated by proinflammatory action of chronic vascular chlamydial infection. We investigated the influence of doxycycline therapy on restenosis rate and adverse clinical event rates after PCI.

View Article and Find Full Text PDF

We discuss the properties of photonic defect modes in cholesteric liquid crystals. Twist defects, isotropic defect layers, and combinations of both are considered. After deriving the reflection and transmission properties of the defects, we study the effect of a finite sample thickness on the defect mode's amplitude and on the required polarization of incident light to excite the defect mode.

View Article and Find Full Text PDF