55 research outputs found

    Post-embryonic changes in Melipona quadrifasciata anthidioides Lep. IV. Development of the digestive tract (1)

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    No presente trabalho estuda-se o desenvolvimento post-embrionário do tubo digestivo de Melipona quadrifasciata anthidioides. Cada uma das três partes do canal alimentar (estomódeo, mesentério e proctódeo) são tratadas isoladamente. O aspecto larval de cada porção é descrito antes de expor as transformações que ocorrem posteriormente. a maioria das tranformações post-embrionárias do tubo digestivo ocorrem durante a pupação, mas algumas ocorrem já na larva ou durante a fase de pré-pupa. A Tabela I é uma sinopse das mudanças pos-embrionárias que ocorrem nessas três fases. como pode ser visto as mudanças se iniciam 2 dias após a eclosão da larva e estão completas quando a pigmentação do corpo se inicia na pupa, ou seja, 6 dias antes da emergência

    Genomic profiling of type-1 adult diabetic and aged normoglycemic mouse liver

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    Background: Hyperglycemia induces chromatin remodeling with consequences on differential gene expression in mouse hepatocytes, similar to what occurs during aging. The liver is the central organ for the regulation of glucose homeostasis and xenobiotic and lipid metabolism and is affected by insulin signaling. The precise transcriptional profiling of the type-1 diabetic liver and its comparison to aging have not been elucidated yet. Methods: Here, we studied the differential genomic expression of mouse liver cells under adult hyperglycemic and aged normoglycemic conditions using expression arrays. Results: Differential gene expression involved in an increase in glucose and impaired lipid metabolism were detected in the type-1 diabetic liver. In this regard, Ppargc1a presents an increased expression and is a key gene that might be regulating both processes. The differential gene expression observed may also be associated with hepatic steatosis in diabetic mouse liver, as a secondary disease. Similarly, middle-aged mice presented differential expression of genes involved in glucose, lipid and xenobiotic metabolism. These genes could be associated with an increase in polyploidy, but the consequences of differential expression were not as drastic as those observed in diabetic animals. Conclusions: Taken together, these findings provide new insights into gene expression profile changes in type-1 diabetic liver. Ppargc1a was found to be the key-gene that increases glucose metabolism and impairs lipid metabolism impairment. The novel results reported here open new areas of investigation in diabetic research and facilitate the development of new strategies for gene therapy

    estudos artísticos

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    A revista Gama, Estudos Artísticos estabeleceu-se como um instrumento para a disseminação do conhecimento em torno da arte e da cultura numa perspetiva que se crê inovadora, e que nos caracteriza: estudar arte e artistas através do olhar formado e privilegiado dos companheiros de profissão. Artistas estudam outros artistas. A revista Gama pertence assim a um projeto de resistência: resistência ao centrismo do artworld, ao esmagamento pelos discursos dominantes, às lógicas de reprodução da legitimação instituída. Há uma característica que prevalece em todos os 28 artigos reunidos na presente edição: a reflexão informada sobre autores e obras de arte, que propõe novas leituras e novas redes de conhecimento. Todas juntas constituem um tecido que descobre sentidos, na sua integração global na nova paisagem cultural.info:eu-repo/semantics/publishedVersio

    Pervasive gaps in Amazonian ecological research

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    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
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