We study radial solutions of a singularly perturbed nonlinear elliptic system of the FitzHughNagumo type. In a particular parameter range, we find a large number of layered solutions. First we show the existence of solutions whose layers are well separated from each other and also separated from the origin and the boundary of the domain. Some of these solutions are local minimizers of a related...

The use of human skin models is a widely accepted approach for studying biology. These include organotypic systems reconstructed from cells as well based on discarded surgical tissue. Cell-based are time-consuming to set up and maintain, unable fully recapitulate the differentiated architecture skin, typically lack minor cell populations. Traditional full-thickness prepared excised tissue colle...

The US Pharmacopeial Convention published the USP <797> Guidebook to Pharmaceutical Compounding— Sterile Preparations in 2008. This publication, which is based on the USP Revised General Chapter <797>, sets practice standards to help ensure that compounded sterile preparations are of high quality. Although these guidelines have not yet been enforced by the Quebec regulatory authority, they will...

We demonstrate an original solution to obtain a single-frequency ring laser coupled to an external passive nonresonant ring cavity, which plays the role of an optical diode. This system provides more output power than systems with an intracavity unidirectional device. To the best of our knowledge, this work marks the first demonstration of a unidirectional planar ring laser at 1.3 microm. Using...