997 resultados para 1764-1842


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We describe Kochiana new genus to accommodate a small Brazilian theraphosine species described originally as Mygale brunnipes by Koch (1842), resulting in Kochiana brunnipes new combination. Recently, specimens were rediscovered in northeastern Brazilian Atlantic rainforest. A preliminary cladistic analysis using equal weights parsimony and implied weights, was carried out to examine its phylogenetic placement. Kochiana new genus was monophyletic in all trees regardless of weighting scheme or concavity used. There is preliminary evidence for Kochiana new genus monophyly and weak evidence for its placement as sister group of Plesiopelma. Kochiana new genus can be characterized by the presence of a hornshaped spermatheca in females and males with a palpal bulb having prolateral accessory keels and a well developed medial crest on the embolus apex.

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When carrying out experiments on the production of the edible mushroom Pleurotus sajor-caju in the Laboratory of Edible Mushrooms, Universidade Federal de Lavras, Lavras, Brazil, in the second half of 2007, the presence of beetles later identified as belonging to the species Mycotretus apicalis was verified. This is the first recorded instance of this insect in cultures of P. sajor-caju in Brazil. The larvae and adults of this insect feed on the fruiting bodies of commercial harvests, resulting in reduction in mushroom quality. To provide evaluation of the injuries caused by these insects, substrates colonized by P. sajor-caju were infested with 4, 8, 16, 32 and 64 insects per block of substrate being the qualitative and quantitative losses then noted. Despite the lack of an observed decrease in biological efficiency, the injuries caused by these insects affected the commercial quality of the mushrooms, which may result in economic losses. The results showed that infestations of 32 insects per 0.8 kg of substrate led to a depreciation in the prices of mushrooms meant to be sold.

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Avicularia diversipes (C. L. Koch 1842) known previously only from its original description is redescribed along with Avicularia sooretama sp. nov. and Avicularia gamba sp. nov. The three species are endemic to Brazilian Atlantic rainforest. With other Avicularia species, they share a procurved anterior eye row, slender embolus and medially folded spermathecae, whereas they have unusual characters, such as a very long and spiraled embolus (A. diversipes) and spermathecae with multilobular apex (A. sooretama sp. nov.). Furthermore, the three species lack a tibial apophysis in males and share a distinctive color pattern ontogeny that is not known in any other Avicularia species. The conservation status of the three species is discussed, especially with respect to endemism, illegal trafficking and habitat destruction. The creation of protected areas in southern State of Bahia, Brazil, is recommended, as well as the inclusion of these species in IUCN and CITES lists. Appendices with figures and species information are presented to facilitate correct specimen identification by custom officers, in order to limit illegal traffic.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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The impact of pollutants in an organism can be observed by changes in functional complexity at different levels. Bivalve gills are suitable for histopathological analysis because of their structure and function. This study aimed at examining the morphology of Mytella falcata gill filaments from three sites in the Santos estuary (São Paulo, Brazil) with different levels of environmental degradation to identify possible changes in gill structure and discuss the significance of these alterations. For this purpose, histological, histochemical and ultrastructural techniques were used. The filaments of animals from site A (less impacted site) were intact, while in sites B and C, pathological changes were observed, such as: detachment of the epithelium in the intermediate zone, morphological changes of this epithelium, inflammatory process, increase in the number of mucous cells and cell turnover processes. These results suggest that the related changes are an attempt to prevent the entrance of pollutants through gill filaments into the entire organism and that cell turnover is the final way to compensate cell injury. (C) 2008 Elsevier Ltd. All rights reserved

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Pós-graduação em Educação Matemática - IGCE

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Pós-graduação em Ciências Biológicas (Zoologia) - IBB

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This article analyzes the main objectives of the scientific voyage to circumnavigate the earth, undertaken by the United States from 1838 to 1842. Charting was one of the most important of the scientific and strategic goals of the exploratory voyage. The initiative for the undertaking was the search for exact positioning on the high seas after the establishment of the longitude system, when nautical charts and maps from various countries were compared, and other, new ones were drawn. The United States participated in this international effort, leading to the creation of its own cartographic system.

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Analisa o principal objetivo da viagem científica de circunavegação realizada pelos EUA entre 1838 e 1842. A tarefa de mapeamento destaca-se entre outras metas científico-estratégicas da viagem exploratória. A iniciativa da empreitada foi movida pela busca da exata localização em alto-mar após a instituição do sistema de longitudes, quando cartas náuticas e mapas de vários países foram conferidos, e outros, novos, desenhados. Os EUA participaram desse esforço internacional, dando início à constituição de um sistema cartográfico próprio.