Stable free radical from plant litter decomposing in water

The presence of a stable radical species in both fresh straw and that which had been submerged in aerated water for up to six months has been demonstrated using electron paramagnetic (spin) resonance (EPR or ESR) spectroscopy. A radical signal was associated also with material shown to contain straw lignin markers, which was leached from the rotting straw into surrounding water. Fresh straw treated with strong alkali to remove phenolics did not show a radical signal. The possible effect of a dissolved stable free radical is discussed in relation to the antagonistic effect of rotting straw on algal and cyanobacterial growth in water to which straw has been added as a nuisance algal control agent.

Interview method affects incidence of postoperative sore throat

Two hundred and forty-two routine surgical patients who had undergone general anaesthesia, were questioned about postoperative sore throat by one of two methods, either direct or indirect questioning. A significantly higher incidence of sore throat was obtained by direct questioning (p less than 0.001).

Differential transfer in poor and normal readers

It has been suggested that children who sustain specific reading disability experience difficulty in abstracting and generalizing the invariant components of words containing redundant elements because of basic dysfunction in categorical processing. This hypothesis was assessed by comparing independent samples of poor and normal readers on transfer of training tasks of two different types: a visual-verbal association task which simulated the reading process, and a visual-visual association task unlike reading. It was predicted that poor readers would perform significantly below normal readers on both initial learning and transfer under the visual-verbal association conditions. In contrast, it was expected that the performance of similar groups of poor and normal readers would be comparable under the visual-visual training and transfer conditions. The results supported these predictions, and it was concluded that the generalization problems observed in poor readers in early word learning are, most likely, attributable to transfer difficulties associated with specific disorder in visual-verbal integration, rather than primary or basic disorder in categorization ability.