BACKGROUND Atrial tachycardias (AT) during or after ablation of atrial fibrillation frequently pose a diagnostic challenge. We hypothesized that both the patterns and the timing of coronary sinus (CS) activation could facilitate AT mapping. METHODS AND RESULTS A total of 140 consecutive postpersistent atrial fibrillation ablation patients with sustained AT were investigated by conventional ma...

The cumulative retardance Delta(t) introduced between the p and the s orthogonal linear polarizations after two successive total internal reflections (TIRs) inside a right-angle prism at complementary angles phi and 90 degrees - phi is calculated as a function of phi and prism refractive index n. Quarter-wave retardation (QWR) is obtained on retroreflection with minimum angular sensitivity when...

We characterize the director structures in electroconvection patterns of nematic liquid crystals by means of polarising microscopy. This study was stimulated by a theory put forward by Rossberg et al. [1] who propose a mechanism for chevron texture formation. We characterize the relation between the wave vector modulation and in-plane twist modulations of the director field. In addition to the ...

For over 25 years it is known that the roll structure of electroconvection (EC) in the dielectric regime in planarly aligned nematic liquid crystals has, after a transition to defect chaos, the tendency to form chevron structures. We show, with the help of a coarse-grained model, that this effect can generally be expected for systems with spontaneously broken isotropy, that is lifted by a small...

The use of the phase change material (PCM) as a storage medium represents an important advance to store energy for absorption cooling systems when solar is not available; however, temperature tank key parameter adequate operation system. This paper presents parametric analysis flat and commercial plate heat exchangers with MgCl2·6H2O PCM at conditions. exchanger (PHE) chevron type angle 45° are...

BACKGROUND There are two surgical approaches for distal soft-tissue procedures for the correction of hallux valgus-the dorsal first web-space approach, and the medial transarticular approach. The purpose of this study was to compare the outcomes achieved after use of either of these approaches combined with a distal chevron osteotomy in patients with moderate to severe hallux valgus. METHODS ...