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Landing data are the most basic information used to manage fisheries, although they are often unavailable or incomplete. The objective of this work was to reconstruct the national database of marine commercial landings for the Brazilian industrial and artisanal fisheries, from 1950 to 2015. Total landings increased strongly from 1950 to mid-1980s and suffered sharp decline in the early 1990s, mainly associated to the collapse of sardine fisheries. After that, another period of increasing landings was observed, but at a much lower rate. Industrial landings always surpassed artisanal landings in Brazilian waters, except for the beginning of the time series, when many industrial fleets had not started yet, and in the early 2000s, when a change in the methodology for collecting landing statistics was implemented in the state of Pará leading to an overestimation of artisanal landings. Artisanal fisheries have been declining since 2005, which is worrisome due to the social impact it may have on local income and food security. Regional differences were also observed, with industrial landings being always higher than artisanal landings in southeastern-southern Brazil, while the opposite was true for the northern-northeastern regions. Higher landings were observed in the southeastern-southern regions when both artisanal and industrial fleets were combined. Sardine and demersal fishes were the main resources landed by industrial fishers. Artisanal fishers caught more species than their industrial counterpart, featuringXiphopenaeus kroyeri,Cynoscion acoupa, andUcides cordatus. Although the fishing ofEpinephelus itajarawas banned in Brazil, it continues to be landed. Yet, catches of this species and others under some threat status are still not properly registered, including:Carcharhinus longimanus,Galeorhinus galeus,Sphyrna lewini,Sphyrna mokarran,Pristis pectinata, andPseudobatos horkelii. Fishing resources not identified in previous landing reconstruction efforts, such as sea urchins and sea cucumbers, have now been reported. The database presented here should be continuously updated and improved. It is of paramount importance to resume the collection of landing statistics, including information on fishing effort, to assess the relative impact of fisheries and environmental factors on the main Brazilian fishing stocks.

Niobium oxide based thin films were deposited on AISI 316 stainless steel substrates using reactive DC magnetron sputtering. Structure, composition and corrosion resistance of the niobium oxide films were studied. The corrosion behavior of the specimens was evaluated by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The concentration of niobium and oxygen in the films was obtained by Rutherford backscattering spectroscopy (RBS). The film structure was analyzed by X-ray diffractometry. The corrosion resistance of the substrate was improved by the Nb2O5 layers. The best protective performance was achieved for the deposition time of 15 min.

Filmes finos de óxido de nióbio têm sido usados em muitas aplicações tecnológicas. Existem pelo menos três óxidos estáveis de nióbio: NbO, NbO2 e Nb2O5 e cada um deles tem propriedades específicas. O Nb2O5 é a forma termodinamicamente mais estável e apresenta propriedades físicas e químicas únicas, como alto índice de refração, band gap largo, excelente estabilidade química e resistência à corrosão, baixa absorção óptica no campo da luz visível até regiões próximas ao infra-vermelho, sendo amplamente utilizados como filtros de interferência óptica de alta qualidade. Neste trabalho foram depositados filmes de óxido de nióbio por meio da técnica de sputtering reativo sobre substratos de silício e borossilicato. Os filmes finos foram obtidos com vazão de oxigênio variando entre 15 e zero sccm. O objetivo deste trabalho foi a caracterização das propriedades ópticas dos filmes. Foram avaliados o índice de refração e a espessura pela técnica de elipsometria, o band gap pelo método de Tauc e a razão atômica e a densidade superficial por meio de Espectrometria de Retroespalhamento Rutherford (RBS). Foram obtidos espectros de transmitância e refletância por Espectrofotometria UV/Vis/NIR e o coeficiente de extinção foi calculado pelo método de Hong. Todos estes parâmetros são importantes para aplicação em dispositivos ópticos. Nos filmes depositados com vazão de oxigênio de 15 sccm foi observado que o índice de refração aumenta com o aumento da espessura dos filmes e que o composto formado foi Nb2O5. Para uma vazão de 2,0 sccm foi encontrado o composto NbO2 e o filme apresentou alta absorção ótica. Os resultados sugerem que outros óxidos de nióbio ou nióbio metálico foram incorporados nos filmes conforme o fluxo de oxigênio foi diminuído. Foi observada uma relação direta entre a diminuição da vazão de oxigênio durante a deposição e um aumento da quantidade de nióbio nos filmes, acompanhados de um aumento do índice de refração e da densidade superficial. Niobium oxide thin films have been used in many technological applications. There are at least three stable niobium oxides: NbO, NbO2 and Nb2O5 and each one has specific properties. The Nb2O5 is the most stable thermodynamically form having unique physical and chemical properties such as high refractive index, wide band gap, excellent chemical stability and corrosion resistance, low optical absorption in the field of visible light to near the infrared regions, being widely used as high quality optical interference filters. In this work niobium oxide thin films were deposited by reactive sputtering technique on silicon and borosilicate substrates. The films were obtained by using oxygen flow rates varying from 15 up to zero sccm. The objective of this work was the optical characterization of niobium oxide films. The refractive index and the thickness were evaluated by ellipsometry technique, the band gap by TAUC method and the atomic ratio and the surface density by means of Rutherford backscattering spectrometry (RBS). Spectral transmittance and reflectance spectrophotometry by UV / Vis / NIR curves were obtained and the extinction coefficient was calculated by the method of Hong. All of these parameters are important for application in optical devices. In the films deposited with oxygen flow of 15 sccm it was observed that the refractive index increases with increasing thickness of the films and analyzes indicated that Nb2O5 forms for when a flow rate of 15 sccm is used. For a flow rate of 2.0 sccm it was found NbO2 and a high optical absorption. As the flow of oxygen used in the deposition of the films was decreased, there were signs that were incorporated in the films other oxides of niobium or niobium metal itself. A direct relationship between decreased of oxygen flow during deposition and a increase in niobium quantity in the films, accompanied by an increase in the refractive index and surface density was observed.

The Barra das Jangadas estuarine system is located at the Jaboatão dos Guararapes Town, 20km south of Recife city, and it is formed by the Pirapama and Jaboatão Rivers. The area main economical activity is the artisanal fisheries. The objective of this paper is to evaluate the environmental quality through the phytoplankton biomass spatial distribution and the hydrological parameters. Surface samples (dissolved oxygen, BOD, temperature, salinity, nutrients, chlorophyll-a and suspended material) were collected in 15 fixed stations with a Nansen bottle during diurnal low tide. The phytoplankton biomass presented a maximum of 111.13mg.m3 indicating an euthrophic condition. Nutrients weren’t limitant to the phytoplankton development, presenting a non conservative pattern. Ammonium, phosphate and silicate influenced the primary biomass, being removed from nearly all estuary. The high N:P ratio indicated anthropic impacts as domestic and/or industrial pollution, and the biological uptake or sedimentation of the phosphate compounds. The salinity pattern showed a vertical homogenous estuary. According to Principal Component Analysis the phytoplankton biomass showed a high direct correlation with the suspended material, while the dissolved oxygen, saturation tax, salinity, pH and transparence presented direct correlation among them and were inversely correlated to the nutrients and BOD. O sistema estuarino de Barra das Jangadas localiza-se no município de Jaboatão dos Guararapes 20km ao sul da cidade do Recife, sendo formado pelos rios Pirapama e Jaboatão e cuja a atividade econômica predominante é a pesca artesanal. Este trabalho teve como objetivo avaliar a distribuição espacial da biomassa fitoplanctônica e dos parâmetros hidrológicos pra caracterizar as condições ambientais da referida área. As amostras foram coletadas com garrafa de Nansen, na superfície, em 15 estações fixas durante baixamar diurna. Para tal, analisou-se o teor de oxigênio dissolvido e taxa de saturação, DBO, temperatura, salinidade, nutrientes, clorofilaa e material em suspensão. A biomassa fitoplanctônica apresentou um comportamento eutrófico com teor máximo de 111,13mg.m3 . Os nutrientes não foram fatores limitantes para o desenvolvimento fitoplanctônico, apresentando os mesmos um padrão não conservativo. A Amônia, o fosfato e o silicato foram os que mais influenciaram a biomassa primária, sendo removidos praticamente em toda a porção do estuário. A relação N:P elevada comprovou a existência de ações antrópicas como poluição doméstica ou industrial, e a remoção biológica ou sedimentação de compostos fosfatados. O padrão de salinidade mostrou tratar-se de um estuário verticalmente homogêneo. De acordo com a Análise de Componentes Principais a biomassa fitplanctônica mostrou uma alta correlação direta com o material em suspensão enquanto o oxigênio dissolvido, taxa de saturação, salinidade, pH e transparência da água apresentaram uma alta correlação direta entre si e inversa com os sais nutrientes e a DBO.