OBJECTIVE Several factors, such as homeostatic and circadian influences, may affect the density of cortical and subcortical arousals (AR). The purpose of this study was to examine the time-of-night and the first night effect on AR response. METHODS AR were classified into microarousals (MA), phases of transitory activation (PAT), delta (D-burst) and K-complex burst (K-burst). The AR density a...

A study has been conducted on amine-cured epoxy resins and the effects on the ultimate burst strength of internally loaded glass-reinforced filament-wound vessels when these rosins were used as the plastic matrices. The tensile properties of the niatrLx were changed by systematically altering the molecular structure of the amine-cured epoxy resin. It was found that resintensile properties had a...

Extracellular recordings were obtained from the ganglion cell (GC) layer during correlated spontaneous bursting activity (SBA) in the immature turtle retina. Pharmacological agents were bath-applied, and their effects on burst and correlation parameters were determined. SBA requires synaptic transmission. It was blocked in the presence of curare and mecamylamine, two cholinergic nicotinic antag...

Fluoride ion (F-) is an effective activator of the respiratory burst in neutrophils, as indicated by its ability to induce O2- production by these cells. Other halide ions did not activate the burst, Cl-, in particular appeared to antagonize the effect of F- on O2- production. F- stimulated O2- production showed a requirement for Ca++, but was independent of other exogenous cations. Neither pha...

The period of first feeding, when young salmonid fishes emerge from natal stream beds, is one fraught with predation risk. Experiments conducted in semi-natural stream mesocosms have shown that growth hormone transgenic salmonids are at greater risk of predation than their non-transgenic siblings, due partly to the higher metabolic demands associated with transgenesis, which force risky foragin...

BACKGROUND The relationship between measures of drug effect such as bispectral index (BIS) and end-tidal (ET) levels of anaesthetic agents is described by the 'effect site equilibrium half-time', t(1/2)(ke0). There are limited data available on sevoflurane t(1/2)(ke0) during routine anaesthesia and surgery. Preliminary observations suggested t(1/2)(ke0) for the degree of hypnosis as estimated b...

Coupling between cyclically varying external light and an endogenous biochemical oscillator known as the circadian clock, modulates a rhythmic pattern with two prominent peaks in the locomotion of Drosophila melanogaster. A morning peak appears around the time lights turn on and an evening peak appears just before lights turn off. The close association between the peaks and the external 12:12 h...