Time Limitations Enhance Reading Comprehension.

Few studies in the domain of reading have explored the relation between time limitations and reading comprehension. Time limitations may enhance reading comprehension by promoting mindfulness in students, a construct which involves exertion of more effort and motivation. This study explored the effects of time constraints on reading comprehension in adult readers. Mild time constraints should create greater mindfulness in readers, resulting in enhanced comprehension. College students read passages under no time pressure, under mild time pressure, or under severe time pressure. Reading comprehension was assessed in each condition. The best reading comprehension was observed under mild time pressure. Implications are discussed. Copyright 1999 Academic Press.

Effects of dietary treatment of rats with eicosapentaenoic acid or docosahexaenoic acid on hepatic lipid metabolism.

(1) Effects of dietary treatment of male albino rats with eicosapentaenoic acid (EPA) or docosahexaenoic acid on hepatic mitochondrial lipid metabolism have been investigated. (2) Mitochondria isolated from rats given these treatments were shown to have increased ability to respire on acyl-CoA esters in the presence of malonate. This effect was expressed with most of the long-chain acyl-CoA esters used as substrates. When malonate in the incubations was replaced with malate, mitochondria from treated animals were found to exhibit diminished rates of respiration on polyunsaturated acyl-CoA esters, in particular linolenoyl-, eicosapentaenoyl- and docosahexaenoyl-CoA. This phenomenon could not be attributed to changes in activity of carnitine palmitoyltransferase I or in peroxisomal beta-oxidation. (3) Uncoupled respiration on glutamate, malate or succinate was also affected by treatment with EPA. With liver mitochondria isolated from rats that had been treated with a omega-3 fatty acid in the fasted state, the respiratory rates were lower than those observed with mitochondria isolated from control rats. Respiratory rates with mitochondria isolated from rats given the omega-3 fatty acid in the fed state was not significantly different from control rates. (4) In rats treated with EPA in the fed state, the amount of EPA incorporated into mitochondrial lipids was markedly more increased as compared to rats given omega-3 fatty acid in the fasted state. Incorporation of dietary EPA into tissue lipids was investigated, also following mildronate treatment of rats (an inhibitor of carnitine biosynthesis). (5) A hypolipidaemic effect of dietary EPA was only observed when the fatty acid was given to fed rats. Rats treated with EPA in the fasted state, in contrast, exhibited hypoglycaemia, the hypolipidaemic effects now being absent. (6) These results suggest that hypolipidaemia is most pronounced when the metabolic state favours incorporation of dietary EPA into body lipids rather than its beta-oxidation, as mediated by the fed/fasted transition or by treatment with mildronate.