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The combined influence of maturation, ripening, and climate on the profile of bioactive compounds was studied in banana (Musa acuminata, AAA, Cavendish, cv. Grande Naine). Their bioactive compounds were determined by the Folin-Ciocalteu assay and high-performance thin layer chromatographic (HPTLC) method. The polyphenol content of bananas harvested after 400 degree days remained unchanged during ripening, while bananas harvested after 600 and 900 degree days exhibited a significant polyphenol increase. Although dopamine was the polyphenol with the highest concentration in banana peels during the green developmental stage and ripening, its kinetics differed from the total polyphenol profile. Our results showed that this matrix of choice (maturation, ripening, and climate) may allow selection of the banana (M. acuminata, AAA, Cavendish, cv. Grande Naine) status that will produce optimal concentrations of identified compounds with human health relevance.  相似文献   
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Abstract

Football is one of the most common extracurricular activities among schoolchildren. Illusions and expectations are poured into a competitive sport that complements their formal education at school. The controversy over competition in schoolchildren aged six and seven opens up a debate on the lessons that are constructed. This study explores the emotional management that children develop in order to participate in sports activities in relation to the lessons promoted by the school. This article presents an ethnographic study grounded upon participant observation, with 101 schoolchildren in the first and second years of primary school during one academic year in 207 sessions, and semi-structured interviews with 21 teachers. After analysing the narratives, the results reveal previous expectations and stresses, a level of activation adequate for the competitive demands of the environment, the development of the ability to be competent in a stressful situation, the emotional capitalization of knowing how to win and lose, the impact of social recognition on adaptative construction of self-esteem, and the management of episodes of stress.  相似文献   
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Differences in motor performance according to chronological age and gender of 341 young Nigerian children (ages 3 to 5) were examined. Motor test items designed by Morris et al. (1981) were administered to the subjects. Analysis of variance was used to determine significant differences in the motor performance of the groups. In the whole sample, more age differences than sex differences in performance were noted. Except for the balancing and running performances of the girls, a fairly linear trend of improvement with age was observed in the motor performances of the groups. At each age level the boys consistently performed better than the girls in four of the six motor tests (catching, standing long jump, tennis ball throw and speed run). Generally, the 4‐ and 5‐year‐old children performed homogeneously, with a great disparity in performance noted for the 3‐year‐old children. The results of this study confirm that age and sex differences in motor performance occur at early childhood. Prospective studies should seek to control the extraneous factors which influence motor development and account for the observed differences in motor performance of pre‐school children.  相似文献   
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[Abstract) This paper introduces the Scientific Electronic Library Online (SciELO) program and its three main objectives. Then the paper presents the methodology of open access to scientific information by the SciELO. At last, it shows the perspectives of open access in developing countries.  相似文献   
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