460 research outputs found

    Ovulaster protodecimae n. sp. (Echinoidea, Spatangoida) and associated epifauna (Cirripedia, Verrucidae) from the Danian of northeastern Italy

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    A new species of irregular echinoid, Ovulaster protodecimae, is described from the Danian Scaglia Rossa Formation out-cropping in the Venetian Prealps (Southern Alps, northeastern Italy). The new species, belonging to the order Spatangoida, is very distinctive because of its inflated, almost triangular test, the high-positioned peri-proct and the plate arrangement on the oral face. This is the first report of the genus Ovulaster in the Danian of Italy and the first description of an echinoid from the Early Palaeocene of Italy. One test has an epifauna of the sessile verrucid barnacle Verruca sp. cf. V. prisca Bosquet, 1854, attached on all except the oral surface

    LOWER LIMB MUSCLE RECRUITMENT STRATEGIES DIFFER BETWEEN ELITE AND RECREATIONAL ICE HOCKEY PLAYERS

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    Understanding the muscle recruitment strategies that have the largest contribution to performance is essential in sports biomechanics. The aims of this study were to characterise principal muscle activation patterns during accelerative hockey skating and to classify skill levels of players based on their principal muscle activation patterns. Key features of lower limb muscle activation strategies during accelerative skating were extracted and used to classify, with 83% success, elite and recreational players’ acceleration strides. Classification and functional interpretation of muscle coordination is important to understand the differences in muscle recruitment strategies across skill levels, and to monitor changes that result from training

    Professional engineering ethics education: just how effective is it?.

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    Professional engineering degrees that are endorsed through independent protocols, (such as the Washington Accord), must ensure that students are given sufficient background to enable them to practise in an ethically professional manner. Graduates are expected to have a full understanding of the pertinent code(s) of ethics under which they can be expected to function as engineers. Further, they need to be able to appreciate the nuances involved in issues such as 'conflict of interest', sustainability, resource use, quadruple bottom line (the '4Es') as well as 'good practice'. This paper provides a review of the course Ethics and the Professional, currently being offered in four universities in three countries, that was established to directly address the need for professional ethics education. Over the last few years, student satisfaction surveys of this course have been undertaken in Australia, New Zealand and Germany; the results of these are provided herein. In addition to these assessments a further, novel approach, devised to assess the overall effectiveness of the professional ethics course is presented. This assessment provides a valuable tool through which we may monitor any apparent change in student attitudes that developed during the course

    Expression pattern of four storage xyloglucan mobilization-related genes during seedling development of the rain forest tree Hymenaea courbaril L.

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    During seedling establishment, cotyledons of the rain forest tree Hymenaea courbaril mobilize storage cell wall xyloglucan to sustain growth. The polysaccharide is degraded and its products are transported to growing sink tissues. Auxin from the shoot controls the level of xyloglucan hydrolytic enzymes. It is not yet known how important the expression of these genes is for the control of storage xyloglucan degradation. In this work, partial cDNAs of the genes xyloglucan transglycosylase hydrolase (HcXTH1) and β-galactosidase (HcBGAL1), both related to xyloglucan degradation, and two other genes related to sucrose metabolism [alkaline invertase (HcAlkIN1) and sucrose synthase (HcSUS1)], were isolated. The partial sequences were characterized by comparison with sequences available in the literature, and phylogenetic trees were assembled. Gene expression was evaluated at intervals of 6 h during 24 h in cotyledons, hypocotyl, roots, and leaves, using 45-d-old plantlets. HcXTH1 and HcBGAL1 were correlated to xyloglucan degradation and responded to auxin and light, being down-regulated when transport of auxin was prevented by N-1-naphthylphthalamic acid (NPA) and stimulated by constant light. Genes related to sucrose metabolism, HcAlkIN1 and HcSUS1, responded to inhibition of auxin transport in consonance with storage mobilization in the cotyledons. A model is proposed suggesting that auxin and light are involved in the control of the expression of genes related to storage xyloglucan mobilization in seedlings of H. courbaril. It is concluded that gene expression plays a role in the control of the intercommunication system of the source–sink relationship during seeding growth, favouring its establishment in the shaded environment of the rain forest understorey

    Nutritional reserves of Vochysiaceae seeds: chemical diversity and potential economic uses

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    Contents of proteins, carbohydrates and oil of seeds of 57 individuals of Vochysiaceae, involving one species of Callisthene, six of Qualea, one of Salvertia and eight of Vochysia were determined. The main nutritional reserves of Vochysiaceae seeds are proteins (20% in average) and oils (21. 6%). Mean of carbohydrate contents was 5. 8%. Callisthene showed the lowest protein content (16. 9%), while Q. cordata was the species with the highest content (30% in average). The contents of ethanol soluble carbohydrates were much higher than those of water soluble carbohydrates. Oil contents lay above 20% for most species (30. 4% in V. pygmaea and V. pyramidalis seeds). The predominant fatty acids are lauric (Q. grandiflora), oleic (Qualea and Salvertia) or acids with longer carbon chains (Salvertia and a group of Vochysia species). The distribution of Vochysiaceae fatty acids suggests for seeds of some species an exploitation as food sources (predominance of oleic acid), for other species an alternative to cocoa butter (high contents or predominance of stearic acid) or the production of lubricants, surfactants, detergents, cosmetics and plastic (predominance of acids with C20 or C22 chains) or biodiesel (predominance of monounsaturated acids). The possibility of exploitation of Vochysiaceae products in a cultivation regimen and in extractive reserves is discussed.Teores de proteínas, carboidratos solúveis e óleos de sementes de 57 indivíduos de Vochysiaceae, compreendendo uma espécie de Callisthene, seis de Qualea, uma de Salvertia e oito de Vochysia foram determinados. As principais reservas de sementes de Vochysiaceae são proteínas (20% em média) e óleos (21, 6%). A média dos teores de carboidratos foi de 5, 8%. Callisthene apresentou o mais baixo teor de proteínas (16, 9%), enquanto Q. cordata foi a espécie com o mais elevado teor (30% em média). Teores de carboidratos solúveis em etanol foram muito superiores aos solúveis em água. Os teores de óleo foram superiores a 20% na maioria das espécies (30, 4% em V. pygmaea e V. pyramidalis). Ácidos graxos predominantes foram láurico (Q. grandiflora), oleico (Qualea e Salvertia) ou ácidos com cadeias mais longas (Salvertia e um grupo de espécies de Vochysia). A distribuição de ácidos graxos de Vochysiaceae sugere para as sementes de algumas espécies o uso em alimentação (predominância de ácido oléico), para outras, uma alternativa à manteiga de cacau (teores elevadosde ácido esteárico) ou produção de lubrificantes, tensoativos, detergentes, cosméticos e plásticos (predominância de ácidoscom cadeias C20 ou C22) ou biodiesel (predominância de ácidos monoinsaturados). Discute-se a possibilidade de aproveitamento de produtos de Vochysiaceae em regime de cultivo eem reservas extrativas.Conselho Nacional do Desenvolvimento Científico e Tecnológico (CNPq

    Socio-Economic Disparities in the Burden of Seasonal Influenza: The Effect of Social and Material Deprivation on Rates of Influenza Infection

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    There is little empirical evidence in support of a relationship between rates of influenza infection and level of material deprivation (i.e., lack of access to goods and services) and social deprivation (i.e. lack of social cohesion and support).Using validated population-level indices of material and social deprivation and medical billing claims for outpatient clinic and emergency department visits for influenza from 1996 to 2006, we assessed the relationship between neighbourhood rates of influenza and neighbourhood levels of deprivation using Bayesian ecological regression models. Then, by pooling data from neighbourhoods in the top decile (i.e., most deprived) and the bottom decile, we compared rates in the most deprived populations to the least deprived populations using age- and sex-standardized rate ratios.Deprivation scores ranged from one to five with five representing the highest level of deprivation. We found a 21% reduction in rates for every 1 unit increase in social deprivation score (rate ratio [RR] 0.79, 95% Credible Interval [CrI] 0.66, 0.97). There was little evidence of a meaningful linear relationship with material deprivation (RR 1.06, 95% CrI 0.93, 1.24). However, relative to neighbourhoods with deprivation scores in the bottom decile, those in the top decile (i.e., most materially deprived) had substantially higher rates (RR 2.02, 95% Confidence Interval 1.99, 2.05).Though it is hypothesized that social and material deprivation increase risk of acute respiratory infection, we found decreasing healthcare utilization rates for influenza with increasing social deprivation. This finding may be explained by the fewer social contacts and, thus, fewer influenza exposure opportunities of the socially deprived. Though there was no evidence of a linear relationship with material deprivation, when comparing the least to the most materially deprived populations, we observed higher rates in the most materially deprived populations

    Short- and long-term temperature responses of soil denitrifier net N2O efflux rates, inter-profile N2O dynamics, and microbial genetic potentials

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    Production and reduction of nitrous oxide (N2O) by soil denitrifiers influence atmospheric concentrations of this potent greenhouse gas. Accurate projections of the net N2O flux have three key uncertainties: (1) short- vs. long-term responses to warming, (2) interactions among soil horizons, and (3) temperature responses of different steps in the denitrification pathway. We addressed these uncertainties by sampling soil from a boreal forest climate transect encompassing a 5.2 ∘C difference in the mean annual temperature and incubating the soil horizons in isolation and together at three ecologically relevant temperatures in conditions that promote denitrification. Both short-term exposure to warmer temperatures and long-term exposure to a warmer climate increased N2O emissions from organic and mineral soils; an isotopic tracer suggested that an increase in N2O production was more important than a decline in N2O reduction. Short-term warming promoted the reduction of organic horizon-derived N2O by mineral soil when these horizons were incubated together. The abundance of nirS (a precursor gene for N2O production) was not sensitive to temperature, whereas that of nosZ clade I (a gene for N2O reduction) decreased with short-term warming in both horizons and was higher from a warmer climate. These results suggest a decoupling of gene abundance and process rates in these soils that differs across horizons and timescales. In spite of these variations, our results suggest a consistent, positive response of denitrifier-mediated net N2O efflux rates to temperature across timescales in these boreal forests. Our work also highlights the importance of understanding cross-horizon N2O fluxes for developing a predictive understanding of net N2O efflux from soils

    Short- and long-term temperature responses of soil denitrifier net N2O efflux rates, inter2 profile N2O dynamics, and microbial genetic potentials

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    Production and reduction of nitrous oxide (N2O) by soil denitrifiers influence atmospheric concentrations of this potent greenhouse gas. Accurate projections of the net N2O flux have three key uncertainties: (1) short- vs. long-term responses to warming, (2) interactions among soil horizons, and (3) temperature responses of different steps in the denitrification pathway. We addressed these uncertainties by sampling soil from a boreal forest climate transect encompassing a 5.2 ∘C difference in the mean annual temperature and incubating the soil horizons in isolation and together at three ecologically relevant temperatures in conditions that promote denitrification. Both short-term exposure to warmer temperatures and long-term exposure to a warmer climate increased N2O emissions from organic and mineral soils; an isotopic tracer suggested that an increase in N2O production was more important than a decline in N2O reduction. Short-term warming promoted the reduction of organic horizon-derived N2O by mineral soil when these horizons were incubated together. The abundance of nirS (a precursor gene for N2O production) was not sensitive to temperature, whereas that of nosZ clade I (a gene for N2O reduction) decreased with short-term warming in both horizons and was higher from a warmer climate. These results suggest a decoupling of gene abundance and process rates in these soils that differs across horizons and timescales. In spite of these variations, our results suggest a consistent, positive response of denitrifier-mediated net N2O efflux rates to temperature across timescales in these boreal forests. Our work also highlights the importance of understanding cross-horizon N2O fluxes for developing a predictive understanding of net N2O efflux from soils
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