28 research outputs found

    Selection of yeast strains for bioethanol production from UK seaweeds

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    Macroalgae (seaweeds) are a promising feedstock for the production of third generation bioethanol, since they have high carbohydrate contents, contain little or no lignin and are available in abundance. However, seaweeds typically contain a more diverse array of monomeric sugars than are commonly present in feedstocks derived from lignocellulosic material which are currently used for bioethanol production. Hence, identification of a suitable fermentative microorganism that can utilise the principal sugars released from the hydrolysis of macroalgae remains a major objective. The present study used a phenotypic microarray technique to screen 24 different yeast strains for their ability to metabolise individual monosaccharides commonly found in seaweeds, as well as hydrolysates following an acid pre-treatment of five native UK seaweed species (Laminaria digitata, Fucus serratus, Chondrus crispus, Palmaria palmata and Ulva lactuca). Five strains of yeast (three Saccharomyces spp, one Pichia sp and one Candida sp) were selected and subsequently evaluated for bioethanol production during fermentation of the hydrolysates. Four out of the five selected strains converted these monomeric sugars into bioethanol, with the highest ethanol yield (13 g L−1) resulting from a fermentation using C. crispus hydrolysate with Saccharomyces cerevisiae YPS128. This study demonstrated the novel application of a phenotypic microarray technique to screen for yeast capable of metabolising sugars present in seaweed hydrolysates; however, metabolic activity did not always imply fermentative production of ethanol

    Psychological adjustment and quality of life in children and adolescents following open-heart surgery for congenital heart disease: a systematic review

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    BACKGROUND: Children with congenital heart defects (CHD) requiring open-heart surgery are a group at high risk for health-related sequelae. Little consensus exists regarding their long-term psychological adjustment (PA) and health-related quality of life (QoL). Thus, we conducted a systematic review to determine the current knowledge on long-term outcome in this population. METHODS: We included randomized controlled trials, case control, or cohort studies published between 1990-2008 evaluating self- and proxy-reported PA and QoL in patients aged between two and 17 years with a follow-up of at least two years after open heart surgery for CHD. RESULTS: Twenty-three studies assessing psychological parameters and 12 studies assessing QoL were included. Methodological quality of the studies varied greatly with most studies showing a moderate quality. Results were as follows: (a) A considerable proportion of children experienced psychological maladjustment according to their parents; (b) studies on self-reported PA indicate a good outcome; (c) the studies on QoL suggest an impaired QoL for some children in particular for those with more severe cardiac disease; (d) parental reports of psychological maladjustment were related to severity of CHD and developmental delay. CONCLUSION: A significant proportion of survivors of open-heart surgery for CHD are at risk for psychological maladjustment and impaired QoL. Future research needs to focus on self-reports, QoL data and adolescents
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