This paper investigates the avalanche photodiode (APD) gain effect on spectral-amplitude coding optical code-division multiple-access (SAC-OCDMA) system using a modified-AND subtraction detection in comparison to the conventional AND detection scheme. Analytical results are presented to investigate the APD gain impact on the bit-error rate (BER) performance. In addition, we confirm the influenc...

BACKGROUND The arrhythmogenic effects of hyperthermia have been highlighted in the Brugada syndrome but remain largely unexplored in other arrhythmic syndromes. The present study examines the effect of hyperthermia on transmural dispersion of action potential duration (TD-APD), early afterdepolarization (EAD) activity, and torsade de pointes (TdP) under long-QT conditions. METHODS AND RESULTS...

Anti-arrhythmic drug therapy is a frontline treatment for atrial fibrillation (AF), but its success rates are highly variable. This is due to incomplete understanding of the mechanisms of action of specific drugs on the atrial substrate at different stages of AF progression. We aimed to elucidate the role of cellular, tissue and organ level atrial heterogeneities in the generation of a re-entra...

Does APD Gradient Indicate Dispersion of Repolarization ? To the Editor: The article by Glukhov et al1 is a very important study, providing, as it does, direct measurement of action potential durations (APD) transmurally in the human heart. We commend the authors for providing the first evidence for M cells in the human heart. However, we dispute the assumption throughout the article that APD g...

Livshitz LM, Rudy Y. Regulation of Ca and electrical alternans in cardiac myocytes: role of CAMKII and repolarizing currents. Am J Physiol Heart Circ Physiol 292: H2854–H2866, 2007. First published February 2, 2007; doi:10.1152/ajpheart.01347.2006.—Alternans of cardiac repolarization is associated with arrhythmias and sudden death. At the cellular level, alternans involves beat-to-beat oscillat...

The purpose of this study was to determine if peripheral hearing loss of varying degrees in elderly subjects affected performance on monotic auditory processing disorder (APD) tests. A battery of monotic APD tests was administered to a group of well-educated and high-functioning older adults who were divided into three subgroups based on hearing acuity but similar in age: (1) normal hearing out...

INTRODUCTIONS The widespread use of prenatal ultrasonography results in increased recognition of congenital hydronephrosis, a therapeutic and diagnostic challenge. This study was conducted to investigate the natural course of prenatal hydronephrosis and the accuracy of postnatal APD in determining the outcome. MATERIALS AND METHODS All newborns with prenatal hydronephrosis were followed up by...

The influence of activation sequences on action potential configuration, especially in the repolarization phase, was examined in isolated canine ventricular muscles. Action potentials were recorded from the epicardial surface in the center of a preparation having nearly uniform fiber orientation (25 X 25 mm). Stimuli applied just adjacent to the recording site produced nearly centrifugal propag...

BACKGROUND This study assessed the relationship between working memory capacity and auditory stream segregation by using the concurrent minimum audible angle in children with a diagnosed auditory processing disorder (APD). METHODS The participants in this cross-sectional, comparative study were 20 typically developing children and 15 children with a diagnosed APD (age, 9-11 years) according t...

Alternans of cardiac repolarization is associated with arrhythmias and sudden death. At the cellular level, alternans involves beat-to-beat oscillation of the action potential (AP) and possibly Ca(2+) transient (CaT). Because of experimental difficulty in independently controlling the Ca(2+) and electrical subsystems, mathematical modeling provides additional insights into mechanisms and causal...