139 research outputs found
RELATÓRIO TÉCNICO DOS CRUZEIROS DO PROJETO VIEIRA. I. CRUZEIRO 1(4 A 9 DE DEZEMBRO DE 1995)
Main technical results and original data of Cruise I of the Scallop Project (December 4 to 9, 1995) are presented in this Report. Sampling sites were distributed along seven transects, between the 30 and 50 meters isobaths, according to information of previous surveys carried out in 1975. Salinity and temperature of the water column, and sediment samples were obtained at each sampling site for a physical characterisation of the scallop grounds. Two types of beam-trawl and one dredge were tested to catch scallops and benthic samples. Salinity and temperature showed an important gradient, with high temperatures and low salinities at surface waters, and low temperature and high salinities at bottom waters. Sediments were constituted by pure fine to very fine sands. Organic matter and calcium carbonate content, together with other statistical sediment parameters, showed a bathymetrical variation. Along the study area, two beds were found, at SSE of Bom Abrigo Island (São Paulo State) and E of São Francisco do Sul Island (Santa Catarina State), both between 36 and 40 m depth. Very low scallop catches were probably related to a total depletion of the original stock. Future cruises will try to determine the efficiencies of the beam-trawl for a real estimation of scallops densities.Neste relatório são apresentados os dados originais e principais resultados técnicos do Cruzeiro I do Projeto Vieira, realizado entre 4 e 9 de dezembro de 1995. As estações de amostragem foram distribuídas ao longo de 7 transversais entre as isóbatas de 30 e 50 m, em áreas de reconhecida ocorrência de vieiras no passado. Foram obtidos perfis verticais de temperatura e salinidade da água em todas as estações, bem como amostras de sedimento, visando uma caracterização física da região. Dois tipos de beam trawl e uma draga foram empregados na captura de vieira e amostras da macrofauna bentõnica. A temperatura e a salinidade mostraram um gradiente acentuado, com altas temperaturas e baixas salinidades em superfície, e baixas temperaturas e altas salinidades junto ao fundo. Os sedimentos são constituídos de areia fina a muito fina. Tanto os parâmetros granulométricos como o conteúdo de matéria orgânica e carbonato de cálcio mostraram um gradiente batimétrico em seus valores. Ao longo da área de estudo, foram encontrados dois bancos de vieira, um a SSE da Ilha do Bom Abrigo, no litoral sul de São Paulo, e outro a E da Ilha de São Francisco do Sul, no norte de Santa Catarina, ambos entre 36 e 40 metros de profundidade. Entretanto, as capturas em ambos os bancos foram reduzidas, indicando, provavelmente, a ocorrência de uma depleção total no estoque original. Em cruzeiros futuros, a eficiência de captura do beam trawl será determinada com o objetivo de realizar uma estimação real da densidade de vieiras nas áreas
Talitridae (AMPHIPODA, CRUSTACEA) in estuarine beaches of Paranaguá Bay, southern Brazil: spatial distribution and abundance
The only family of Amphipoda with terrestrial representatives is the Talitridae. Four species are present along the Brazilian coast, three of which appear in the Bay of Paranaguá Complex, Atlantorchestoidea brasiliensis, Talorchestia tucurauna and Platorchestia monodi. Samples collected at the wrack line of eleven beaches of the complex showed that drift line was composed by vegetal fragments from mangroves and salt marshes, except for one beach where macroalgae prevail. T. tucurauna showed the highest densities, but occurred at only 5 beaches. This species was positively correlated with salinity suggesting weak osmotic tolerance, which could explain the restricted spatial distribution. In spite of the low abundance of P. monodi, the species occurred in all the eleven beaches. P. monodi was also positively correlated with the wrack biomass, probably using this material for protection against predation and desiccation.The only family of Amphipoda with terrestrial representatives is the Talitridae. Four species are present along the Brazilian coast, three of which appear in the Bay of Paranaguá Complex, Atlantorchestoidea brasiliensis, Talorchestia tucurauna and Platorchestia monodi. Samples collected at the wrack line of eleven beaches of the complex showed that drift line was composed by vegetal fragments from mangroves and salt marshes, except for one beach where macroalgae prevail. T. tucurauna showed the highest densities, but occurred at only 5 beaches. This species was positively correlated with salinity suggesting weak osmotic tolerance, which could explain the restricted spatial distribution. In spite of the low abundance of P. monodi, the species occurred in all the eleven beaches. P. monodi was also positively correlated with the wrack biomass, probably using this material for protection against predation and desiccation
Preliminary analysis of the genetic variability of two natural beds of the Scallop Euvola ziczac (Linnaeus, 1758) in Brazil
Euvola ziczac (formerly Pecten ziczac), a simultaneous hermaphroditic scallop was heavily fished in
Brazil between 1972 and 1980. The production peaked in 1980 with 8,800 tons and was followed by the
total collapse of the resource. In order to investigate the possible loss of genetic variability of the stock
associated to overfishing and self-fertilization, the polymorphism of phosphoglucomutase (PGM) and
glucose phosphate isomerase (GPI) was analyzed by electrophoresis of the adductor muscle of scallops
from São Francisco (26° 20.583S; 48° 16.507W) and Bom Abrigo (25° 28.735S; 47° 37.621W) beds;
the southern and northern extremes of the scallop fishing ground, respectively. Animals from São
Francisco showed a strong deficiency of heterozygosity for GPI and PGM. In addition, PGM showed
*exclusive alleles for each bed. Such results coupled with other information about the species
suggested the following hypothesis: a) the stock was a metapopulation with at least two populations; b)
some reproductive isolation might be occurring which might be influenced by conditions of larval
transport and by the extremely low densities of scallops; c) presently, the stock seemed to be mostly
maintained through self-fertilization; d) São Francisco could constitute a source-area, contributing with
larvae and recruits to Bom Abrigo and other areas; e) both beds were suffering a genetic
homogenization more evident in São Francisco. Such hypothesis needed to be investigated in order to
furnish guidelines for future programs of recovery and management of the resource.info:eu-repo/semantics/publishedVersio
Modeling of Thermodynamic Properties and Phase Equilibria for the Al-Sm Binary System
The thermodynamic properties and associated phase equilibria for the Al-Sm binary system are examined, and experimental results regarding the stability of the Al3Sm, Al11Sm3, and Al4Sm intermetallics are incorporated. In the analysis presented, the liquid phase is described using a three-species association model, the intermediate phases are treated as stoichiometric compounds, and the terminal phases are treated as solid solutions with a single sublattice model. In addition to the stable phases, thermodynamic descriptions of the metastable Al11Sm3-α and Al4Sm-γ phases are employed, and both stable and metastable phase equilibria are presented over the full composition range, providing a general model, which is consistent with available experimental data. Metastable liquidus curves are examined with respect to the observed crystallization behavior of amorphous Al-Sm alloys
Distribuição espacial e temporal de espécies de Bledius (Coleoptera, Staphylinidae) em praias arenosas no sul do Brasil
Visceral leishmaniasis caused by Leishmania infantum in a Spanish patient in Argentina: What is the origin of the infection? Case report
BACKGROUND: The question "Where have you been?" is a common one asked by doctors in Northern Europe and America when faced with clinical symptoms not typical of their country. This question must also arise in the clinics of developing countries in which non-autochthonous cases such as the one described here can appear. Important outbreaks of Leishmania infantum have been recorded in the last decade in several Latin American countries but its presence has not yet been recorded in Argentina. We report the first case of visceral leishmaniasis owing to L. infantum in this country. CASE PRESENTATION: A 71-year-old Spanish woman who has been living in Mendoza, Argentina, during the last 40 years presented with a history of high fever and shivering, anemia, leukopenia and splenomegaly over two years. Argentinian doctors did not suspect visceral leishmaniasis even when the histological analysis revealed the presence of "intracytoplasmatic spheroid particles compatible with fungal or parasitic infection". After a serious deterioration in her health, she was taken to Spain where she was evaluated and visceral leishmaniasis was established. Specific identification of the parasite was done by PCR-ELISA, isoenzyme electrophoresis and RAPD-PCR. CONCLUSION: We would like to point out that: i) cases such as the one described here, which appear in non-endemic areas, can pass unnoticed by the clinical physician. ii) in countries in which these introduced cases reside, in-depth parasitological studies are required into vectors and possible reservoirs to rule out the rare case of local infection and, once infection has taken place, to ensure that this does not spread by anthroponotic transmission or a competent reservoir
Nycthemeral and Monthly Occupation of the Fish Assemblage on a Sheltered Beach of Baía Norte, Florianópolis, Santa Catarina State, Brazil
Interpreting fish community records is challenging for several reasons, including the lack of past ichthyofauna data, the cyclical temporal variations in the community, and the methodology employed, which usually underestimates fish assemblages. The objective of this study was to describe short-scale and meso-scale (nycthemeral period and months, respectively) temporal variations in the ichthyofauna composition and structure of a sheltered beach of Baía Norte (Florianópolis, Santa Catarina state, Brazil), using a capéchade net. Samples were collected monthly for a period of 48 hours. During the period from December 2010 to November 2011, a total of 19,302 individuals belonging to 89 species and 39 families were captured. The number of individuals that were sampled during the day and/or night was dependent on the sampling month. On average, the daytime assemblage was more abundant and different in structure and composition than the nighttime assemblage. Of the eight species that had the highest Index of Relative Importance (%IRI), five had higher variations (ANOVA F) between the day and night than between the months. This finding reinforced the need for sampling during both the day and night. The capéchade net effectively captured demersal and pelagic individuals in a broad range of sizes
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