This work correlates time series of biological and physical variables to the marine viruses across trophic gradients within Arraial do Cabo upwelling system, Southeast of Brazil. The objective is to investigate the major controlling factors of virioplankton dynamics among different water masses. It was used an in situ and ex situ flow cytometry for accessing the plankton community. Viruses were highly correlated to bacteria and phytoplankton, but although the lack of direct correlation with physicals, upwelling turned out to be the main contributing factor to the highest values of viral abundance and virus:bacterial ratio.Our data suggest that the lowest temperature of upwelled South Atlantic Central Waters would help to maintain a high viral abundance and higher temperatures of Coastal and Tropical Waters might be another ecological niche allowing the co-existence.

Short-period variability in plankton communities is poorly documented, especially for variations occurring in specific groups in the assemblage because traditional analysis is laborious and time-consuming. Moreover, it does not allow the high sampling frequency required for decision making. To overcome this limitation, we tested the submersible CytoSub flow cytometer. This device was anchored at a distance of approximately 10 metres from the low tide line at a depth of 1.5 metres for 12 hours to monitor the plankton at a site in the biological reserve of Barra da Tijuca beach, Rio de Janeiro. Data analysis was performed with two-dimensional scatter plots, individual pulse shapes and micro images acquisition. High-frequency monitoring results of two interesting groups are shown. The abundance and carbon biomass of ciliates were relatively stable, whereas those from dinoflagellates were highly variable along the day. The linear regression of biovolume measures between classical microscopy and in situ flow cytometry demonstrate high degree of adjustment. Despite the success of the trial and the promising results obtained, the large volume of images generated by the method also creates a need to develop pattern recognition models for automatic classification of in situ cytometric images.Keywords: aquatic systems, microbial ecology, in situ flow cytometry, method. Usando imagem de citometria de fluxo in situ de ciliados e dinoflagelados para o monitoramento de sistemas aquáticos ResumoA variabilidade de curto período em comunidades do plâncton é pouco documentada, especialmente as variações que ocorrem em grupos específicos das assembleias por causa das análises tradicionais serem muito trabalhosas e demoradas. Além disso, não permitem que a alta frequência amostral necessária para a tomada de decisão. Para superar esta limitação, nós testamos o CytoSub, um citômetro de fluxo submersível. Este aparelho foi ancorado a aproximadamente 10 metros de distância da linha de maré baixa a uma profundidade de 1,5 metros por 12 horas para monitorar o plâncton em um sítio da reserva biológica da praia da Barra da Tijuca, Rio de Janeiro. A análise dos dados foi realizada a partir de gráficos de dispersão bidimensionais, pelas assinaturas ópticas individuais escaneadas (pulse shape profile) e aquisição de micro imagens. Resultados do monitoramento de alta frequência de dois grupos interessantes são apresentados.A abundância e a biomassa de carbono de um grupo de ciliados foram relativamente estáveis, ao passo que o grupo de dinoflagelado, foi altamente variável ao longo do dia. O modelo de regressão linear das medidas de biovolume entre a clássica microscopia e a citometria de fluxo in situ apresentou alto grau de ajustamento. Apesar do sucesso deste ensaio e dos resultados promissores obtidos, o grande volume de imagens geradas por este método também gerou a necessidade de se desenvolver modelos de reconhecimento de padrões para a classificação automática de imagens de citometria in situ.Palavras-chave: sistemas aquáticos...

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Over the last decades, alloy 718 usage has expanded and requirements imposed by its industrial applications became more critical. The knowledge about grain boundary character distribution (GBCD) in alloy 718 and its effect on properties improvement is mostly built based on iterative processing through cold rolling steps interspersed with solution annealing. Alloy 718 is found in the industry in many different forms and geometries, and fabricated by multiple thermomechanical processes such as wire drawing, rolling, forging or extrusion. The present study focused on understanding how wires respond to deformation mode related to drawing in regard to GBCD evolution, crystallographic orientation, precipitation of δ-phase and grain size. Lastly, assessing the resulting mechanical properties. The findings show that microstructural evolution is a consequence of competing mechanisms such as strain induced boundary migration, recrystallization, grain growth and phase precipitation. The deformation gradient along wire cross section plays an important role in affecting microstructural features, such as δ precipitation, GBCD and microtexture.

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Decision-making in coastal waters management is a complex and interdisciplinary task. Particularly, to find seasonal patterns and ecological thresholds, which are not always clear in tropical areas. Therefore, the ultimate in this activity is to gain knowledge about biogenic element, the biological response, and the selection of indicators which may reveal the trophic status of the system. Under this scenario, this paper applies Data Mining techniques as an alternative approach in order to access hidden patterns of in situ flow cytometry monitoring data. The case studied is the upwelling influenced bay at Cabo Frio Island (Rio de Janeiro-Brazil). A neural network uses phytoplankton and bacterial data of real time monitoring as input variables to forecast marine viruses temporal variability. We also demonstrate that it is possible to access patterns of planktonic community structure in different water masses within a set of association rules.

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