The network of regions shown by functional imaging studies to be deactivated by experimental tasks relative to nominally more passive baselines (task < baseline) may reflect processes engaged during the resting state or "default mode." Deactivation may result when attention and resources are diverted from default-mode processes toward task processes. Aging is associated with altered patterns of...

Diagnosis of patients with a disorder of consciousness is very challenging. Previous studies investigating resting state networks demonstrate that 2 main features of the so-called default mode network (DMN), metabolism and functional connectivity, are impaired in patients with a disorder of consciousness. However, task-induced deactivation--a third main feature of the DMN--has not been explored...

1. Paramyotonia congenita (PC) is a human hereditary disorder wherein missense mutations in the skeletal muscle sodium channel lead to cold-exacerbated muscle hyperexcitability. The most common site for PC mutations is the outermost arginine of domain i.v. segment 4 (human R1448, rat R1441). 2. We examined the rat homologues of two PC mutants with changes at this site: R1441P and R1441C. The R-...

Pretreatment of lignocellulosic materials may result in the release of inhibitors and deactivators of cellulose enzyme hydrolysis. We report the identification of phenols with major inhibition and/or deactivation effect on enzymes used for conversion of cellulose to ethanol. The inhibition effects were measured by combining the inhibitors (phenols) with enzyme and substrate immediately at the b...

Cognitive processing is associated with deactivation of the default mode network. The presence of dopaminoceptive neurons in proximity to the medial prefrontal node of this network suggests that this neurotransmitter may modulate deactivation in this region. We therefore used positron emission tomography to measure cerebral blood flow in 15 Parkinson's disease (PD) patients while they performed...

PURPOSE OF REVIEW As the use of intracardiac devices has increased, the awareness of the burdens of the devices, especially the uncomfortable defibrillator shocks, has also increased. Some patients have requested device deactivation and some physicians have expressed reluctance to do so. This review will update physicians about the ethical acceptability of removal of intracardiac devices. REC...

In this study, the hydrolysis of pretreated sorghum stem and rice husk was investigated at various initial enzyme concentrations and substrate loadings. The slowdown in enzymatic hydrolysis of lignocellulosic materials with conversion has often been attributed to decreasing the activity of enzyme. A kinetic model was developed and expressed mathematically based on enzyme deactivation for enzyma...

Deactivation of commercially relevant cobalt catalysts for Low Temperature Fischer-Tropsch (LTFT) synthesis is discussed with a focus on the two main long-term deactivation mechanisms proposed: Carbon deposits covering the catalytic surface and re-oxidation of the cobalt metal. There is a great variety in commercial, demonstration or pilot LTFT operations in terms of reactor systems employed, c...

The small GTPase Rab5 regulates the early endocytic pathway of transferrin (Tfn), and Rab5 deactivation is required for Tfn recycling. Rab5 deactivation is achieved by RabGAP5, a GTPase-activating protein, on the endosomes. Here we report that recruitment of RabGAP5 is insufficient to deactivate Rab5 and that developmentally regulated GTP-binding protein 2 (DRG2) is required for Rab5 deactivati...