Abnormal atrial refractoriness was examined as a cause of atrial fibrillation/flutter (AFF) in patients with bradycardia. Refractory periods at three disparate right atrial sites were compared in 17 patients with sinus node dysfunction (SND) and 16 controls. Atrial pacing shortened refractory periods, but failed to decrease dispersion of refractoriness significantly. During sinus rhythm, durati...

BACKGROUND Patients with sinus node dysfunction (SND) have increased risk of atrial tachyarrhythmias, including atrial fibrillation (AF). To date, treatment patterns and outcomes of patients with SND and AF have not been well described. HYPOTHESIS Patients with SND and AF have higher risk of adverse cardiovascular outcomes. METHODS Sinus node dysfunction was defined clinically, based on tre...

Sympathetic nerve discharge (SND) responses to hyperthermia are attenuated in aged rats without heart failure (HF) and in young HF (Y(HF)) rats, demonstrating that individually aging and HF alter SND regulation. However, the combined effects of aging and HF on SND regulation to heat stress are unknown, despite the high prevalence of HF in aged individuals. We hypothesized that SND responses to ...

We tested the hypothesis that sustained elevation in mean arterial pressure (MAP) alters the frequency-domain characteristics of efferent sympathetic nerve discharge (SND) after the return of MAP to control levels. Renal, lumbar, and splanchnic SND were recorded before, during, and after a 30-min increase in MAP produced by phenylephrine (PE) infusion in α-chloralose-anesthetized, spontaneously...

Symbolic noise detection (SND) has been shown to be highly effective in the Noisy Iterated Prisoner’s Dilemma, in which an action can accidentally be changed into a different action. This paper evaluates this technique in two other 2 × 2 repeated games: the Noisy Iterated Chicken Game (ICG) and the Noisy Iterated Battle of the Sexes (IBS). We present a generalization of SND that can be wrapped ...

This paper presents an original filtering approach, called SND (Scoringbased Neighborhood Dominance), for the subgraph isomorphism problem. By reasoning on vertex dominance properties based on various scoring and neighborhood functions, SND appears to be a filtering mechanism of strong inference potential. For example, the recently proposed method LAD is a particular case of SND. We study a spe...

Renal and splanchnic sympathetic nerve discharge (SND) responses to increased (38-41 degrees C) internal temperature were determined in anesthetized young (3-6 mo old), mature (12 mo old), and senescent (24 mo old) Fischer 344 (F344) rats. We hypothesized that SND responses would be altered in senescent and mature rats as demonstrated by attenuated sympathoexcitatory responses to heating and by...

Simultaneous nitrification denitrification (SND) has been referred to as a biological process for nitrogen removal where nitrification and denitrification occur concurrently in the same aerobic reactor. SND facilities, investigated in this study, have been shown to remove 80 to 96 percent nitrogen without additional carbon and alkalinity. Carbon availability and bulk dissolved oxygen (DO) conce...

The term SSS was coined by Ferrer in 1968 who grouped together all the anatomic etiologies of sinus node disease (SND).1 Table1. We will explore how some patients with underlying SND can have coexisting AF either the effect of SND on atria via various mechanisms or via the underlying disease of the atria. SND is frequently associated with AF, forming the basis of the ”tachycardia-bradycardia sy...