574 research outputs found

    Are metals of antifouling paints transferred to marine biota?

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    Devido sua alta toxicidade, o TBT está banido desde 2003, o que resultou na re-utilização de tintas a base de cobre. O objetivo deste trabalho é determinar se os metais provenientes das tintas anti-incrustantes (AFP) são transferidos para organismos bentônicos da Baía de Guanabara (BG) (Rio de janeiro, Brasil). Concentrações de metais foram analisadas em duas espécies de algas Ulva flexuosa e U. fasciata e no isópoda, Sphaeroma serratum, em duas áreas de marinas em locais de substrato artificial coberto com tintas AFP e em locais de substrato natural. Também foram coletadas amostras em uma área oceânica (controle). Concentrações de Cd, Cr, Cu, Pb e Zn foram determinadas por Espectrofotometria de Absorção Atômica. Concentrações mais elevadas de Cu, Pb e Zn foram detectadas na BG em ambas espécies de algas em relação a área controle. Dentre as espécies de algas e do isópoda da BG, as populações coletadas sobre as superfícies cobertas com AFP apresentaram concentrações significativamente mais elevadas do que as populações do substrato natural. Os resultados obtidos demonstram que a liberação de metais presentes nas AFP dos decks e embarcações, estão sendo acumulados pelas algas e isópodas. Esses resultados indicam que o revestimento com AFP é a principal fonte de metais para a biota de marinas em áreas da BG.Because of its high toxicity, TBT (trybutiltin) was banned since 2003, which resulted in a greater re-use of Cu as based-biocide in antifouling paints (AFP). The aim of this work is to determine if metals form of AFP are transferred to benthic organisms from Guanabara Bay (GB) (Rio de Janeiro, Brazil). Metal concentrations were measured in two main fouling algae species Ulva flexuosa and U. fasciata and one isopod species, Sphaeroma serratum, in two GB marinas areas from sites with artificial substrate covered by AFP and natural substrate.In addition, control samples were collected in an adjacent open ocean area. Concentrations of Cd, Cr, Cu, Pb and Zn were determined by Atomic Absortion Spectrophotometry. Higher concentrations of Cu, Pb and Zn were detected in both algal species from GB in relation to control areas. Among samples of algae and isopod species from GB, populations collected over artificial surfaces covered by AFP presented significantly higher metal concentration than population of rocky natural substrate. Our data showed that the leaching of metals by antifouling paints present on decks and boats are being taken up by algae and isopods. These results indicate that antifouling coatings are the main source of heavy metal to biota of GB marina area

    Rhodoliths and rhodolith beds

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    Rhodolith (maërl) beds, communities dominated by free living coralline algae, are a common feature of subtidal environments worldwide. Well preserved as fossils, they have long been recognized as important carbonate producers and paleoenvironmental indicators. Coralline algae produce growth bands with a morphology and chemistry that record environmental variation. Rhodoliths are hard but often fragile, and growth rates are only on the order of mm/yr. The hard, complex structure of living beds provides habitats for numerous associated species not found on otherwise entirely sedimentary bottoms. Beds are degraded locally by dredging and other anthropogenic disturbances, and recovery is slow. They will likely suffer severe impacts worldwide from the increasing acidity of the ocean. Investigations of rhodolith beds with scuba have enabled precise stratified sampling that has shown the importance of individual rhodoliths as hot spots of diversity. Observations, collections, and experiments by divers have revolutionized taxonomic studies by allowing comprehensive, detailed collection and by showing the large effects of the environment on rhodolith morphology. Facilitated by in situ collection and calibrations, corallines are now contributing to paleoclimatic reconstructions over a broad range of temporal and spatial scales. Beds are particularly abundant in the mesophotic zone of the Brazilian shelf where technical diving has revealed new associations and species. This paper reviews selected past and present research on rhodoliths and rhodolith beds that has been greatly facilitated by the use of scuba

    Seaweed diversity associated with a Brazilian tropical rhodolith bed

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    This study describes the predominantly tropical, subtidal seaweed populations growing on rhodoliths between 4 and 18 m depth in the southern part of Espírito Santo State (Brazil). Qualitative and quantitative sampling revealed species-rich algal communities, comprising 167 species. Three species of rhodophytes represent new records for the Brazilian marine flora (Lithothamnion muelleri, Scinaia aborealis, and Mesophyllum engelhartii). Marked seasonal differences in fleshy algal species composition and abundance were related to seasonal instabilities caused by winter-storm disturbance over the rhodolith beds. In relation to depth, rhodolith density appears to be an important factor for the variation in the abundance of fleshy algae. The rhodolith community is composed of at least seven nongeniculate crustose coralline algal species. Rhodolith beds in southern Espírito Santo State, in an area of 150 km2, provide an important habitat for epibenthic communities, supporting 25% of the known macroalgal species richness along the Brazilian coast.Web of Scienc

    PERSPECTIVA DE EDUCAÇÃO AMBIENTAL NA GESTÃO UNIVERSITÁRIA: O CASO DA UFS

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    A pesquisa tem como objetivo analisar a importância da implantação de um sistema de gestão ambiental na Universidade Federal de Sergipe, priorizando a educação e a consolidação de normas ambientais universitárias. Especificamente, objetiva: a) identificar os exemplos de gestão ambiental adotados por outras instituições de ensino superior; b) descrever a experiência de gestão ambiental na UFS; c) investigar a percepção dos alunos da UFS acerca do meio ambiente; d) verificar a compreensão dos alunos sobre a aplicação de normas ambientais; e) propor medidas para implementar a educação ambiental na comunidade universitária. Trata-se de pesquisa quanti-qualitativa e estudo de caso. Foram entrevistados 95 discentes de várias áreas de conhecimento, além de pesquisa bibliográfica realizada no período de um ano, entre agosto de 2008 e julho de 2009. Dentre os resultados, destacam-se os seguintes: são tímidos os Sistemas de Gestão Ambiental implementados nas universidades brasileiras; na UFS existem ações pontuais pautadas na redução do desperdício de recursos; existe uma compreensão por parte dos alunos acerca do meio ambiente e uma disposição favorável à mudança de normas, visando à sustentabilidade; medidas podem ser adotadas para incrementar ações que favoreçam a gestão e educação ambiental na UFS

    Correlation between Lumbar Lordosis Angle and Degree of Gynoid Lipodystrophy (Cellulite) in Asymptomatic Women

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    INTRODUCTION: Gynoid lipodystrophy (cellulite) has been cited as a common dermatological alteration. It occurs mainly in adult women and tends to gather around the thighs and buttocks. Its presence and severity have been related to many factors, including biotype, age, sex, circulatory changes, and, as some authors have suggested, mechanical alterations such as lumbar hyperlordosis. OBJECTIVE: To correlate the degree of cellulite with the angle of lumbar lordosis in asymptomatic women. METHODS: Fifty volunteers were evaluated by digital photos, palpation, and thermograph. The degree of cellulite was classified on a scale of 1-4. Analyses were performed on the superior, inferior, right and left buttocks (SRB, IRB, SLB, ILB), and the superior right and left thighs (SRT, SLT). The volunteers underwent a lateral-view X-ray, and the angle of lumbar lordosis was measured using Cobb's method (inferior endplate of T12 and the superior endplate of S). The data were statistically analyzed using ANOVA and Spearman's correlation. A significance level of 5% was adopted. RESULTS: Volunteers had a mean age of 26.1 ± 4.4 years and a mean body mass index of 20.7 ± 1.9 kg/m². There was no significant difference in lumbar lordosis angle between those with cellulite classes 2 and 3 (p > 0.297). There was also no correlation between lumbar lordosis angle and the degree of cellulite (p > 0.085 and r > 0.246). CONCLUSIONS: The analysis suggests that there is no correlation between the degree of cellulite and the angle of lumbar lordosis as measured using Cobb's method

    First report of Sporolithon ptychoides (Sporolithales, Corallinophycidae, Rhodophyta) for the Atlantic Ocean

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    Samples corresponding to Sporolithon ptychoides Heydrich were collected in the mesophotic zone (50 m depth) south of Espírito Santo State, Brazil. The collected material presented features characteristic of the species namely: tetrasporangia of 75-105 x 40-55 μm grouped into sori that are raised above the surrounding vegetative thallus surface; presence of a basal layer of elongate cells in areas where the tetrasporangia develop; presence of buried tetrasporangial compartments deep in the thallus; and 3-5 cells in the tetrasporangial paraphyses. These same features said to collectively characterise S. ptychoides, were all observed in a representative specimen and the type specimen of Sporolithon dimotum (Foslie & Howe) Yamaguishi-Tomita ex M.J Wynne. 2 This latter species is thus conspecific with S. ptychoides and is therefore considered a heterotypic synonym thereof as S. ptychoides has nomenclatural priority. This study expands the known geographical distribution of the species and may give insight into the origin of the species into other geographical regions.Web of Scienc

    Rhodolith bed structure along a depth gradient on the northern coast of bahia state, brazil

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    O objetivo deste estudo foi determinar a estrutura de um banco de rodolitos ao longo de um gradiente de profundidade na plataforma em frente à cidade de Salvador, nordeste brasileiro. Foram analisadas as dimensões, a forma e composição das algas calcárias dos rodolitos, bem como a vitalidade, densidade e flora associada ao banco, em três profundidades: 5, 15 e 25 m. As amostras foram obtidas por meio de mergulho autônomo no verão de 2007. Cinco espécies de algas calcárias formadoras de rodolito foram identificadas: Sporolithon episporum, Lithothamnion brasiliense, Lithothamnion superpositum, Mesophyllum erubescens e Lithophyllum sp. A forma de crescimento incrustante e a forma esférica foram predominantes em todas as profundidades. Houve uma redução da dimensão e vitalidade dos rodolitos e um aumento da densidade com a profundidade. Cinqüenta e seis espécies de macroalgas foram encontradas como flora associada aos rodolitos. A profundidade mais rasa apresentou os maiores valores de biomassa e número de espécies de macroalgas. Esses resultados, associados com outras descrições recentes de bancos de rodolitos, indicam que o padrão estrutural desses bancos no Brasil, ao longo de gradientes de profundidade, pode estar relacionado a uma combinação da extensão e da inclinação da plataforma continental.The aim of this study was to determine the structure of a rhodolith bed along a depth gradient of 5 to 25 m in the shelf in front of Salvador City, a region of northeastern Brazil. The dimensions, morphology and coralline algae composition of the rhodoliths were analyzed, as well as the vitality, density, and associated flora of the bed at three depths: 5, 15 and 25 m. Samples were obtained by SCUBA divers in summer 2007. Five rhodolith-forming taxa were identified: Sporolithon episporum, Lithothamnion brasiliense, Lithothamnion superpositum, Mesophyllum erubescens, and Lithophyllum sp. The encrusting growth form and the spherical shape were predominant at all depths. Rhodolith dimensions and vitality decreased and the density increased from the shallow to the deepest zones. Fifty-six macroalgal species were found as rhodolith-associated flora. The shallower depth presented higher values for macroalgal biomass and number of species. These results associated with other recent rhodolith bed descriptions indicate that the pattern of Brazilian rhodolith bed structure along depth gradients may be related to a combination of the extent and slope of the continental shelf

    Measurement uncertainty of geometric parameters in weld beads

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    Este trabalho apresenta uma metodologia para estimar a incerteza associada à medição dos parâmetros que definem a geometria do cordão de solda, especificamente da área do cordão, de forma a atender à exigência estabelecida pela norma NBR ISO/IEC 17025. A qualidade geométrica dos corpos de prova utilizados durante as medições foi ainda avaliada através da medição dos desvios geométricos de planeza e de perpendicularidade. As seguintes etapas foram propostas e realizadas: identificação dos parâmetros que definem a geometria do cordão de solda; identificação e estudo das variáveis que afetam a medição destes parâmetros; adoção do modelo matemático para estimativa da incerteza de cada parâmetro; planejamento e execução dos experimentos para o levantamento dos dados, cálculo da incerteza e, finalmente, análise e discussão dos resultados. Através da análise dos resultados foi possível concluir que as incertezas provenientes da calibração do sistema de medição e relativa ao desvio de perpendicularidade contribuíram significativamente para a incerteza final. As análises despertaram uma preocupação com relação aos valores permissíveis para o desvio de perpendicularidade dos corpos de prova utilizados durante as medições.This work presents a methodology to estimate the uncertainty associated to the measurement of the weld bead geometric parameters in order to address the requirements of NBR ISO/IEC 17025 Standard. The specimen geometric quality was additionally evaluated through the measurement of flatness and perpendicularity deviations. The following steps were proposed and executed: identification of weld bead geometric parameters; identification and study of the variables that affect measurement of the identified parameters; adoption of a mathematical model to estimate the uncertainty for each parameter; planning and execution of the experiments for data obtaining; uncertainty determination, analysis and discussion of the results. It was concluded that the most important variables influencing the final uncertainty were the uncertainty associated to the measuring system calibration and the perpendicularity deviation. The analysis warned about the permissible values of perpendicularity deviations of specimens used during the measurements

    Software traceability for multi-agent systems implemented using BDI architecture

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    The development of multi-agent software systems is considered a complex task due to (a) the large number and heterogeneity of documents generated during the development of these systems, (b) the lack of support for the whole development life-cycle by existing agent-oriented methodologies requiring the use of different methodologies, and (c) the possible incompleteness of the documents and models generated during the development of the systems. In order to alleviate the above problems, in this thesis, a traceability framework is described to support the development of multi-agent systems. The framework supports automatic generation of traceability relations and identification of missing elements (i.e., completeness checking) in the models created during the development life-cycle of multi-agent systems using the Belief-Desire-Intention (BDI) architecture. Traceability has been recognized as an important activity in the software development process. Traceability relations can guarantee and improve software quality and can help with several tasks such as the evolution of software systems, reuse of parts of the system, validation that a system meets its requirements, understanding of the rationale for certain design decisions, identification of common aspects of the system, and analysis of implications of changes in the system. The traceability framework presented in this thesis concentrates on multi-agent software systems developed using i* framework, Prometheus methodology, and JACK language. Here, a traceability reference model is presented for software artefacts generated when using i* framework, Prometheus methodology, and JACK language. Different types of relations between the artefacts are identified. The framework is based on a rule-based approach to support automatic identification of traceability relations and missing elements between the generated artefacts. Software models represented in XML were used to support the heterogeneity of models and tools used during the software development life-cycle. In the framework, the rules are specified in an extension of XQuery to support (i) representation of the consequence part of the rules, i.e. the actions to be taken when the conditions are satisfied, and (ii) extra functions to cover some of the traceability relations being proposed and completeness checking of the models. A prototype tool has been developed to illustrate and evaluate the work. The work has been evaluated in terms of recall and precision measurements in three different case studies. One small case study of an Automatic Teller Machine application, one medium case study of an Air Traffic Control Environment application, and one large case study of an Electronic Bookstore application.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
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