963 resultados para Fresh-water Planctomycete


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Forty-five species of ostracoda from the Aquitanian of the Lisbon area, belonging in thirty-two genera, are presented. These are the first species belonging to this group reported for the Miocene formations in Portugal. Ostracoda assemblages are typical of fresh water, brackish and marine environments (littoral and inner continental shelf). References are made to the stratigraphically more significant species. Data on the paleoenvironments are also presented. A list of the studied species includes a comparison with their distribution in the Aquitaine and Rhone Miocene basins.

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The synthetic study of the uppermost Cretaceous of the Beira Litoral (fauna, flora) confirms its upper Campanian-Maastrichtian age. It shows the presence of a tropical to subtropical climate in an area constituted by a low coastal plain only occasionally linked to the sea, saturated with fresh water and possessing accordingly, a predominantely freshwater fauna (Viso, Aveiro); this plain changed towards the interior into a drier more forested zone with a more abundant terrestrial fauna which includes mammals (Taveiro). A thorough study of the chelonian Rosasia, abundant on the coastal plain, was made possible thanks to the discovery of a skull: it demonstrates that the genus belongs to the family Bothremydidae, revalided here. The composition of this family is presented, its phylogenetic and paleobiogeographic relation with the other pleurodires are analyzed, and its diagnosis established. The family is constituted of three groups; Rosasia belongs to one of these, the Bothremys group.

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The synthetic study of the uppermost Cretaceous of the Beira Litoral (fauna, floral confirms its upper Campanian-Maastrichtian age. It shows the presence of a tropical to subtropical climate in an area constituted by a low coastal plain only occasionally linked to the sea, saturared with fresh water and possessing accordingly, a predominantely freshwater fauna (Viso, Aveiro); this plain changed towards the interior into a drier more forested zone with a more abundant terrestrial fauna which includes mammals (Taveiro). A thorough study of the chelonian Rosasia, abundant on the coastal plain, was made possible thanks to the discovery of a skull: it demonstrates that the genus belongs to the family Bothremydidae, revalided here. The composition of this family is presented, its phylogenetic and paleobiogeographic relation with the other pleurodires are analyzed, and its diagnosis established. The family is constituted of three groups; Rosasia belongs to one of rhese, the Bothremys group.

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Trabalho Final de mestrado para obtenção do grau de Mestre em Engenharia Química e Biológica

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A água é um recurso natural único, escasso e essencial a todos os seres vivos, o que a torna um bem de extrema importância. Nos dias de hoje, o desperdício deste bem, aliado ao aumento da sua procura, tornou-se um problema devido à decrescente disponibilidade de água doce no nosso planeta. Todas as águas que rejeitamos depois da sua utilização para diversos fins, designadas de águas residuais, necessitam de tratamento antes de serem devolvidas ao meio ambiente. O seu tratamento é realizado numa Estação de Tratamento de Águas Residuais (ETAR) e o processo de tratamento depende das suas características. A ETAR das Termas de S. Vicente, em Penafiel, trabalha no seu limite de capacidade, apresenta uma sobrecarga hidráulica gerada por uma afluência de águas pluviais e o processamento das lamas geradas não permite uma secagem tão completa como seria desejável. Assim, este trabalho teve como objetivo o estudo do funcionamento desta ETAR com a finalidade de propor soluções que o possam otimizar. As soluções propostas para otimizar o funcionamento da ETAR em estudo são: i) a substituição de grades de limpeza manual por grades de limpeza automática de forma a reduzir a necessidade da intervenção do operador ao nível da remoção e condicionamento dos gradados; ii) a construção de um desarenador arejado que além de remover areias de diâmetro superior a 0,2 mm promove também a remoção de gorduras, protegendo desta forma os equipamentos a jusante da abrasão/desgaste prematuros e reduzindo a formação de depósitos nas tubagens; iii) a construção de um tanque de equalização de forma a garantir uma distribuição mais uniforme dos caudais e da carga poluente; iv) a substituição do enchimento do leito percolador por um meio de suporte plástico que permite atingir melhores eficiências de remoção neste tratamento biológico; v) a alteração do agente de desinfeção para radiação ultravioleta, evitando a adição de produtos químicos na água residual e possível formação de subprodutos prejudiciais ao ambiente, como ocorreria no caso da cloragem; e vi) a substituição da desidratação de lamas em leitos de secagem por filtros de banda, que é um processo mais rápido, que ocupa menos espaço e permite atingir elevadas eficiências de remoção de humidade. Para cada uma das sugestões são apresentadas as correspondentes especificações técnicas e dimensionamento. As sugestões de melhoria apresentadas neste trabalho constituem uma alternativa mais económica do que a ampliação da ETAR, que genericamente corresponde à duplicação da linha de tratamento atual. Devido à menor complexidade em termos de construção, estas sugestões podem vir a ser implementadas num futuro próximo, prolongando assim um pouco mais a vida útil da ETAR atual.

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In 1989, CONTI DÍAZ & RILLA published a hypothesis concerning the as yet unknown ecological niche of Paracoccidioides brasiliensis. The hypothesis proposed a highly efficient paracoccidioidal ecological strategy based on an important natural reservoir of the parasite, probably in heterothermic animals from fresh water environments. Further, the hypothesis proposed, a transient and variable residence in the soil with a wide aleuriospore dispersion throughout the environment together with an elevated capability of infecting humans, and domestic and wild animals. This paper analyzes scientific publications from the IX International Meeting on Paracoccidioidomycosis held in Águas de Lindoia, São Paulo, Brazil from 2-5 October 2005, providing a comparative study among this articles and with other recently published papers and the hypothesis' postulates. Since various findings and observations appear to agree with the postulates, the pursuit of novel, specific research projects in the supposed reservoirs is recommended partially or fully to confirm the hypothesis using classical laboratorial methods and modern molecular biology techniques.

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Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies

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Immature and adult stages of Anopheles (Anopheles) forattinii were collected in the Parque Nacional do Jaú, Novo Airão, Amazonas, Brazil. Larvae and pupae were taken from fresh water among floating plant debris inside flooded "igapó" forest. This species may make use of plant debris for passive dispersal throughout its distribution range.

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Dissertação de mestrado integrado em Engenharia Civil

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Dissertação de mestrado integrado em Engenharia Civil

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Biological invasions have been object of ecological research for years. As one objective, natural scientists investigate the effects of invasive species on ecosystems and their functioning (Levine et al. 2003). However, impacts on ecosystems are also of relevance for society. Changes in ecosystems affect humans in so far as ecosystems provide goods and services, such as fresh water, food and fibbers or recreation, which might be altered due to invasive species. Therefore impacts of biological invasions should be an object of socio-economic interest, which is also demanded by the Convention on Biological Diversity

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Unraveling the effect of selection vs. drift on the evolution of quantitative traits is commonly achieved by one of two methods. Either one contrasts population differentiation estimates for genetic markers and quantitative traits (the Q(st)-F(st) contrast) or multivariate methods are used to study the covariance between sets of traits. In particular, many studies have focused on the genetic variance-covariance matrix (the G matrix). However, both drift and selection can cause changes in G. To understand their joint effects, we recently combined the two methods into a single test (accompanying article by Martin et al.), which we apply here to a network of 16 natural populations of the freshwater snail Galba truncatula. Using this new neutrality test, extended to hierarchical population structures, we studied the multivariate equivalent of the Q(st)-F(st) contrast for several life-history traits of G. truncatula. We found strong evidence of selection acting on multivariate phenotypes. Selection was homogeneous among populations within each habitat and heterogeneous between habitats. We found that the G matrices were relatively stable within each habitat, with proportionality between the among-populations (D) and the within-populations (G) covariance matrices. The effect of habitat heterogeneity is to break this proportionality because of selection for habitat-dependent optima. Individual-based simulations mimicking our empirical system confirmed that these patterns are expected under the selective regime inferred. We show that homogenizing selection can mimic some effect of drift on the G matrix (G and D almost proportional), but that incorporating information from molecular markers (multivariate Q(st)-F(st)) allows disentangling the two effects.

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From March 1985 to February 1987 montly cast net and beach seine sambles were collected at the Marapendi lagoon, Rio de Janeiro, Brazil, to describe its ichthyofauna and analyze associations between species and their distribution in areas with different salinity regimes. A stratified random sampling design was used and the lagoon diveided in four areas (1-4) according to salinity gradient. The "Bravais-Pearson" correlation index was utilized to analyze the similarity between species and between areas and also group them according to the UPGMA method. According to the results eight species groups were established. The majority of the species were wuryhaline, having a marine origin and were distributed in areas 1, 2 and 3 (high salinity areas). The formation of smaller groups with species of fresh water origin, which occurred in areas 2, 3 and 4 is also discussed.

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Eimeria lagunculata, Eimeria mammiformis and Eimeria podocnemis n. spp., are described from the faeces of the fresh-water turtle Podocnemis expansa, in Pará State, north Brasil. Oocysts of E. lagunculata are ellipsoidal, 19.2 x 12.8 (17.0-20.7 x 11.8-14.1) mum, shape-index (= length/ width) 1.5 (1.4-1.7). Oocyst wall about 0.5-0.7 mum thick, with a prominent stopper-like micropyle at one pole. No oocyst residuum and no polar body. Sporocysts elongate ellipsoidal, 11.0 x 5.4 (10.4-11.8 x 5.2-6.0) mum, shape-index 2.0 (1.8-2.1): no Stieda body. A compact, ellipsoidal sporocyst residuum lies between the two sporozoites, which possess a posterior and an anterior refractile body. Oocysts of E. mammiformis broadly ellipsoidal, 30.0 x 19.4 (23.0-37.0 x 16.3-21.5) mum, shape-index 1.5 (1.1-1.9). Oocyst wall about 0.7 mum thick, with a prominent micropyle: no oocyst residuum and rarely a single polar body. Sporocysts ellipsoidal, 15.3 x 7.9 (14.8-17.0 x 7.4-9.6) mum, shape-index 2.0 (1.8-2.2), with a tiny Stieda body. Sporocyst residuum bulky, ellipsoidal: sporozoites with two conspicuous refractile bodies. E. podocnemis has broadly ellipsoidal oocysts, 17.0 x 12.8 (14.8-19.2 x 11.8-14.1) mum, shape-index 1.3 (1.1-1.4). Oocyst wall about 0.5-0.7 mum thick, with no micropyle. No oocyst residuum, but always a single polar body. Sporocysts ellipsoidal, 9.7 x 5.2 (8.9-10.4 x 4.4-6.0) mum, shape-index 1.9 (1.6-2.0), with no Stieda body. Sporocyst residuum bulky, ellipsoidal: sporocysts with 2 refractile bodies. Eimeria carinii n. sp., is recorded from the tortoise Geochelone denticulata, also from Pará. Oocyst wall about 1.2 mum thicl. No micropyle. Oocyst residuum limited to a number (about 10-20) of scattered granules: no polar body. Sporocysts broadly ellipsoidal, and with no Stieda body: they measure 8,8 x 7.3 (8.0-9.0 x 7.0-7.5) mum, shape-index 1.2 (1.1-1.3). Sporocyst residuum bulky, spherical to ellipsoidal: sporozoites possess both posterior and anterior refractile bodies.

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Limnoderetrema tolosai sp. n. (Trematoda, Digenea) within an autochthonous freshwater fish, the silverside Basilichthys autralis Eigenmann, 1927, from Lakes Riñihue and Ranco in Southern Chile is described. The species is distinguished from Limnoderetrema minutum (Manter, 1954) by the presence of one spine in the cirrus and cecal bifurcation nearer to ventral sucker than to pharinx. It is proposed Limnoderetrema macrophallus (Szidat & Nani, 1951) n. comb. (originally Steganoderma). Limnoderetrema tolosai differs from L. macrophallus since it cirrus has a distal spine and by its vitelline follicles distribution. It seems that Limnoderetrema spp. of South America are highly specific unlike L. minutum of New Zealand.