Glutamine transport as a possible regulator of nitrogen catabolite repression in Saccharomyces cerevisiae.

Nitrogen catabolite repression (NCR) is a major transcriptional control pathway governing nitrogen use in yeast, with several hundred of target genes identified to date. Early and extensive studies on NCR led to the identification of the 4 GATA zinc finger transcription factors, but the primary mechanism initiating NCR is still unclear up till now. To identify novel players of NCR, we have undertaken a genetic screen in an NCR-relieved gdh1Δ mutant, which led to the identification of four genes directly linked to protein ubiquitylation.

Dissipative dynamics of a harmonically confined Bose-Einstein condensate.

We study the dissipation of the center of mass oscillation of a harmonically confined condensate in the presence of a disorder potential. An extension of the harmonic potential theorem allows one to formulate the dynamics from the point of view of an oscillating disorder potential. This formulation leads to a rigorous result for the damping rate in the limit of weak disorder.

Varicella zoster induced cardiac dysfunction: a case report.

A case is presented of cardiac arrhythmia associated with varicella zoster infection, affecting a 34-year-old man. The patient presented with episodes of seizure-like activity, which were subsequently shown to be caused by ventricular fibrillation. The literature regarding this unusual complication of varicella zoster infection is discussed, as it affects both children and adults.

Making polysomnography more "child friendly:" a family-centered care approach.

With the increasing recognition of pediatric sleep disorders, there is a growing demand for pediatric sleep medicine services, including polysomnography. The procedure of polysomnography can be particularly challenging in young children with limited ability to cooperate, especially when they have developmental disabilities or other medical complications. This article describes a family-centered care approach to polysomnography in children that is appropriate in any type of sleep laboratory setting.

Nonlinear screening in two-dimensional electron gases.

We have performed self-consistent calculations of the nonlinear screening of a point charge Z in a two-dimensional electron gas using a density functional theory method. We find that the screened potential for a Z=1 charge supports a bound state even in the high-density limit where one might expect perturbation theory to apply. To explain this behavior, we prove a theorem to show that the results of linear response theory are in fact correct even though bound states exist.