A Morphology-Based Model to Describe the Low-Temperature Impact Behaviour of Rubber-Toughened Polypropylene.

The roles of the rubber particle size, the rubber particle size distribution and the constitutive behaviour of the isotactic polypropylene matrix have been studied by combining the Lazerri-Bucknall energy criterion for cavitation with the Van der Sanden-Meier-Tervoort ligament model adapted for impact conditions. It is concluded that an optimised morphology offers great potential to achieve enhanced mechanical properties with far less rubber and hence achieve a superior stiffness/toughness/processing balance.

Simple Method for the Melt Extrusion of a Cellulose Nanocrystal Reinforced Hydrophobic Polymer.

The rheological properties of a dispersion of cellulose nanocrystals (CNCs) in an aqueous solution of polyoxyethylene (PEO) have been investigated. A peculiar behavior is reported. Upon adding CNC, the viscosity of the suspension first decreases and then increases.

Implantation of a dual-chamber, rate-adaptive pacemaker in a horse with suspected sick sinus syndrome.

A five-year-old gelding suffered syncope at the end of a period of exercise. A 24-hour electrocardiogram recording revealed intermittent pauses in the sinus rhythm of up to 10 seconds, indicating sinus node disease; the pauses occurred repeatedly, particularly after exercise. A dual-chamber, rate-adaptive pacemaker was successfully implanted, which prevented excessive postexercise bradycardia and syncope, and allowed the horse to return to work.

An equine model of chronic atrial fibrillation: methodology.

We describe the development and the different features of an experimental model of chronic atrial fibrillation (AF) in equines. In four healthy ponies a dual-chamber pacemaker, with an adapted pacemaker program, was implanted transvenously in the standing animal. This adapted pacemaker induced episodes of AF by delivering a 2s burst of electrical stimuli (42 Hz) as soon as sinus rhythm was detected.

Dual-chamber pacemaker implantation via the cephalic vein in healthy equids.

The purpose of the present study was to develop a feasible and safe technique for dual-chamber pacemaker implantation in healthy horses. Implantation was performed in a standing, tranquilized horse and in ponies. Atrial and ventricular leads were transvenously inserted through the cephalic vein, and a subcutaneous pacemaker pocket was created between the lateral pectoral groove and the manubrium sterni in 6 equids.