RESUMO Dois morfotipos de Coryphaena hippurus (dourado e palombeta) encontrados ao longo da costa brasileira são considerados espécies diferentes por pescadores e mercadores das regiões de desembarque do estado do Rio de Janeiro. Além disso, esses morfotipos são comercializados por valores diferentes e sofrem diferentes pressões de pesca. Desta forma, a definição do status taxonômico desses morfotipos é importante, tanto em termos econômicos quanto biológicos. A fim de investigar esse problema foi utilizado o método de eletroforese de aloenzimas com a amostragem de dezessete loci para 117 indivíduos dos dois morfotipos de C. hippurus obtidos em desembarques pesqueiros na região de Cabo Frio/RJ (Brasil). Os dados indicaram uma homogeneidade entre os conjuntos gênicos dos morfotipos. A despeito disso, diferenças entre os conjuntos gênicos de dourado e palombeta foram encontradas, devido, especialmente, ao locus álcool desidrogenase. A hipótese de seleção natural é discutida como possível explicação para esses resultados.

ABSTRACT Two Coryphaena hippurus morphotypes (dourado and palombeta) are found along the Brazilian coast and are considered by Rio de Janeiro’s fisherman and fishmongers as two different species. Furthermore, these morphotypes are commercialized under different values and suffer different fishing pressure. Therefore, a definition of their taxonomic status is an important economic and biological matter. In order to investigate this problem, allozyme electrophoresis method was undertaken for seventeen loci on 117 individuals of C. hippurus sampled at Cabo Frio/RJ (Brazil). The data indicate homogeneity between the morphotypes gene pools. Nevertheless, differences were found for genetic variation among dourado and palombeta, especially due to alcohol dehydrogenase locus. Natural selection hypothesis is discussed in explaining these findings.

Neste trabalho, foi desenvolvido e caracterizado um compósito híbrido com memória de forma (SMAHC) por meio de uma análise teórico-experimental, no regime elástico, envolvendo a fabricação de vigas laminadas. A viga híbrida foi confeccionada em matriz de epóxi reforçada com fios de SMA e mantas de fibras picadas de vidro-E, com e sem bolsa de vácuo, de cura a frio e quente. A viga possui duas camadas de fios, com e sem roving, afastadas simetricamente o máximo possível do plano médio. Também foram produzidas vigas semelhantes, com e sem fios de aço galvanizado. Os módulos de elasticidade à flexão das vigas foram comparados aos módulos de simulações analíticas. O principal objetivo foi avaliar o aumento controlado da rigidez à flexão quando os fios de Ni-Ti (SMA) foram aquecidos, por efeito Joule, de 25°C a 69°C. As vigas de SMAHC, com fração volumétrica de Ni-Ti até 2%, tiveram um aumento no módulo de elasticidade de até 6,53%, apenas mudando a fase dos fios de martensita (25ºC) para austenita (69ºC).

In this paper, a shape memory alloy hybrid composite (SMAHC) was developed and characterized by theoretical and experimental analysis, in the elastic regime, involving the fabrication of laminated beams. The hybrid beam was made of epoxy matrix reinforced with SMA wires and E-glass chopped mat, with and without vacuum bag, as well as cold and hot curing. The two plies incorporating wires reinforced with roving or not, were symmetrically distributed along the thickness direction, as far as possible from the beam´s middle surface. Similar specimens were also produced, substituting the Ni-Ti (SMA) wires by cheaper galvanized steel wires. The flexure elasticity modulus of the beams was compared with those obtained analytically. The main objective was to evaluate the bending stiffness of the beams, when the temperature of the Ni-Ti wires was increased by Joule effect, from 25 ºC and 69 ºC. The SMAHC beams, with volume fraction of Ni-Ti up to 2%, presented an increase in the modulus, up to 6.53 %, by changing the phase of the wires, from the martensite (25 ºC) to the austenite (69 ºC).

A reference inventory of prehistoric marine mollusks from the Rio das Ostras region was created based on an excavation carried out at the Sambaqui da Tarioba shellmound. Patterns of richness and biogeography were studied, and the representativeness of bivalve and gastropod diversities found at this archaeological site were inferred. A total of 47 taxa belonging to 28 families, most of which from unconsolidated substrates, was identified. The shellmound species composition does not differ from the present-day composition. All recorded species are characteristic of a wide transition zone between the south of the states of Espírito Santo (21°S) and Rio Grande do Sul (32°S). Thus, the data show little evidence of evolution in the composition, richness,and biodiversity distribution patterns of mollusks in the Rio das Ostras region. Likewise, a reconstitution of the paleoenvironment from the functional characteristics of the shellmound species indicates that the locality's geomorphology and climate remained largely unchanged in the last 4,000 years BP.