998 resultados para 13078-011


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This paper describes inter-specific differences in the distribution of sediment in the gut compartments and in the enzyme and bacterial profiles along the gut of abyssal holothurian species - Oneirophanta mutabilis, Psychropotes longicauda and Pseudostichopus villosus sampled from a eutrophic site in the NE Atlantic at different times of the year. Proportions of sediments, relative to total gut contents, in the pharynx, oesophagus, anterior and posterior intestine differed significantly in all the inter-species comparisons, but not between inter-seasonal comparisons. Significant differences were also found between the relative proportions of sediments in both the rectum and cloaca of Psychropotes longicauda and Oneirophanta mutabilis. Nineteen enzymes were identified in either gut-tissue or gut-content samples of the holothurians studied. Concentrations of the enzymes in gut tissues and their contents were highly correlated. Greater concentrations of the enzymes were found in the gut tissues suggesting that they are the main source of the enzymes. The suites of enzymes recorded were broadly similar in each of the species sampled collected regardless of the time of the year, and they were similar to those described previously for shallow-water holothurians. Significant inter-specific differences in the gut tissue concentrations of some of the glycosidases suggest dietary differences. For example, Psychropotes longicauda and Pseudostichopus villosus contain higher levels of chitobiase than Oneirophanta mutabilis. There were no seasonal changes in bacterial activity profiles along the guts of O. mutabilis and Pseudostichopus villosus. In both these species bacterial activity and abundance declined between the pharynx/oesophagus and anterior intestine, but then increased along the gut and became greatest in the rectum/cloaca. Although the data sets were more limited for Psychropotes longicauda, bacterial activity increased from the anterior to the posterior intestine but then declined slightly to the rectum/cloaca. These changes in bacterial activity and densities probably reflect changes in the microbial environment along the guts of abyssal holothurians. Such changes suggest that there is potential for microbial breakdown of a broader range of substrates than could be otherwise be achieved by the holothurian itself. However, the present study found no evidence for sedimentary (microbial) sources of hydrolytic enzymes.

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This series of research vignettes is aimed at sharing current and interesting research findings from our team and other international researchers. In this vignette, Dr Martie-Louise Verreynne from the University of Queensland Business School summarises the findings from a paper written in conjunction with Sarel Gronum, that examines how much innovation is enough and does it really matter. They found that innovation does matter, however careful consideration of the innovation - performance relationship is important.

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C 15H 1602 (a synthetic precursor to dodecahedrane), monoclinic, P21/n, a = 12.171 (5), b = 6.976(5), c = 13.868 (3) A, B = 102.56 (3) ° , Z = 4, D m = 1.30, D c = 1.318 g cm -3, F(000) = 488, g(Mo K¢t) = 0.92 cm- 1. Intensity data were collected on a Nonius CAD-4 diffractometer and the structure was solved by direct methods. Full-matrix least-squares refinement gave R = 0.077 (R w = 0.076) for 1337 observed reflections. All the five-membered rings are cis fused and have envelope (C s symmetry) conformations.

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O presidente da Assembleia Nacional Constituinte (ANC) Ulysses Guimarães (PSDB-SP) preside a cerimônia em homenagem ao segundo aniversário de morte de Tancredo Neves. Imagem de Risoleta Neves, esposa de Tancredo Neves, em plenário. O Deputado Pimenta da Veiga (PMDB-MG) discursa em nome do PMDB. O Deputado Aécio Neves (PMDB-MG) agradece a homenagem póstuma ao avô. As três Subcomissões da Educação, Cultura e Esportes; da Ciência e da Comunicação; da Família, do Menor e do Idoso que fazem parte da Comissão da Família, Educação e Cultura, Esporte, Ciência e Tecnologia e da Comunicação reuniram-se para tratar de questões como o livro didático, a destinação de verbas governamentais para o ensino público e privado e da educação pré-escolar. O Senador João Calmon (PMDB-ES) acredita numa projeção da educação. A Subcomissão da Família, do Menor e do Idoso recebeu Comba Marques Porto, representante do Conselho dos Direitos da Mulher, que relatou sobre a natureza da sociedade conjugal. A Deputada Rita Camata (PMDB-ES), em entrevista, aborda também a questão da sociedade conjugal. O Ministro Chefe da Casa Civil, Marco Maciel, esteve presente na Subcomissão do Poder Executivo.

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Recent measurements on dendrochronologically-dated wood from the Southern Hemisphere have shown that there are differences between the structural form of the radiocarbon calibration curves from each hemisphere. Thus, it is desirable, when possible, to use calibration data obtained from secure dendrochronologically-dated wood from the corresponding hemisphere. In this paper, we outline the recent work and point the reader to the internationally recommended data set that should be used for future calibration of Southern Hemisphere 14C dates.