The depletion of gluons as the parton flux traverses a nucleus in a heavy-ion collision can influence the production rate of heavy-quark states. Thus the suppression of J/ψ can be due to gluon depletion in the initial state in addition to nuclear and hadronic absorption in the final state. A formalism is developed to describe the depletion effect. It is shown that, without constraints from othe...

We have investigated the potential cytoprotective role of endoplasmic reticulum (ER) molecular chaperones in a cultured cell model of renal ischemia. Madin-Darby canine kidney (MDCK) cells were pretreated with tunicamycin (an inducer of ER but not cytosolic molecular chaperones) for 12-16 h, followed by 6 h of ATP depletion. A rapid and severe depletion of cellular ATP was noted in both control...

Cognitive effort and self-control are exhausting. Although evidence is ambiguous, behavioural studies have repeatedly suggested that control-demanding tasks seem to deplete a limited cache of self-regulatory resources leading to performance degradations and fatigue. While resource depletion has indirectly been associated with a decline in right prefrontal cortex capacity, its precise neural und...

The human mind is quite adept at modifying and regulating thoughts, judgments, and behaviors. Recent research has demonstrated that depletion of self-regulatory resources can impair executive function through restriction of working memory capacity. The current work explored whether the mere perception of resource depletion (i.e., illusory fatigue) is sufficient to directly produce these deficit...

The present study was designed to determine whether sodium phenylbutyrate (ΦB) acutely induces a decrease in plasma glutamine in healthy humans, and, if so, will decrease estimates of whole body protein synthesis. In a first group of three healthy subjects, graded doses (0, 0.18, and 0.36 g ⋅ kg-1 ⋅ day-1) of ΦB were administered for 24 h before study: postabsorptive plasma glutamine concentrat...

Ornithine decarboxylase (ODC) catalyses the conversion of ornithine to putrescine, an obligate precursor to the polyamines spermidine and spermine. We reported previously that homozygous odc-1 (pc13) worms have no detectable ODC activity. Despite their inability to make polyamines, these mutant worms appear normal, but with a slight reduction in total brood size, when grown in complex medium th...

The TRPV1 ion channel is expressed in nociceptors, where pharmacological modulation of its function may offer a means of alleviating pain and neurogenic inflammation processes in the human body. The aim of this study was to investigate the effects of cholesterol depletion of the cell on ion-permeability of the TRPV1 ion channel. The ion-permeability properties of TRPV1 were assessed using whole...

Our previous studies of Streptococcus faecalis 9790 have shown that the depletion of an essential amino acid from a highly buffered synthetic medium corresponds to the end of the exponential growth phase (log phase) (2, 3). The end of the log phase is followed by further turbidity changes that are characteristic for the particular amino acid studied. The exhaustion of valine is followed by a sl...