Among patients with a Wolff–Parkinson–White (WPW) syndrome, approximately half will experience arrhythmia during their lifetime. Radiofrequency catheter ablation of the accessory atrioventricular pathway is the treatment of choice for this condition and is associated with a high success rate. Electrophysiology study is indeed the key procedure for identifying the target of radiofrequency ablati...

New CORAVEL radial-velocity observations and UBV photometry of 24 red giants in the field of the intermediate-age open cluster Mel 71 are analysed for membership and duplicity. The membership of 16 stars is confirmed, one star is a possible member, and 8 spectroscopic binaries have been discovered , all amongst the cluster stars. Four of their orbits have been determined, with periods ranging f...

We have obtained medium-low resolution spectroscopy and BV I CCD imaging of Berkeley 32, an old open cluster which lies in the anticentre direction. From the radial velocities of 48 stars in the cluster direction we found that 31 of them, in crucial evolutionary phases, are probable cluster members, with an average radial velocity of +106.7 (σ = 8.5) km s. From isochrone fitting to the colour m...

We present integrated photometry and color-magnitude diagrams (CMDs) for 24 star clusters in M33, of which 12 were previously uncataloged. These results are based on Advanced Camera for Surveys observations from the Hubble Space Telescope of two fields in M33. Our integrated V magnitudes and V–I colors for the previously identified objects are in good agreement with previously published photome...

We present B and V photometry of the outlying SMC star cluster BS 196 with the 4.1-m SOAR telescope. The photometry is deep (to V≈25) showing ≈3 mag below the cluster turnoff point (TO) at MV=2.5 (1.03M⊙). The cluster is located at the SMC distance. The colour-magnitude diagram (CMD) and isochrone fittings provide a cluster age of 5.0±0.5Gyr, indicating that this is one of the 12 oldest cluster...

schmelzens, und sind die Tektite von ähnlichem Ausgangsstoff abzuleiten, dann muß man jedoch Fraktionierung von Rb und Sr annehmen, um die Abweichung der Tektitenresultate von der „Isochrone" der Gläser zu erklären. Demnach ist es nicht möglich, genauere Folgerungen aus unseren Messungen hinsichtlich des Ursprungs der EK-Tektite zu gewinnen. Es ist jedoch gesichert, daß eine deutliche Ähnlichke...

We describe a technique to identify Be stars in open clusters using Strömgren b, y, and narrow-band Hα photometry. We first identify the B-type stars of the cluster using a theoretical isochrone fit to the (b−y, y) color-magnitude diagram. The strongest Be stars are easily identified in a (b−y, y−Hα) color-color diagram, but those with weaker Hα emission (classified as possible Be star detectio...

A phase resetting curve (PRC) measures the transient change in the phase of a neural oscillator subject to an external perturbation. The PRC encapsulates the dynamical response of a neural oscillator and, as a result, it is often used for predicting phase-locked modes in neural networks. While phase is a fundamental concept, it has multiple definitions that may lead to contradictory results. We...

A general method is presented for constructing distribution functions for flat systems whose surface density and Toomre's Q number profile is given. The purpose of these functions is to provide plausible galactic models and assess their critical stability with respect to global non axi-symmetric modes. The derivation may be carried out for an azimuthal velocity distribution (or a given specific...