1,415 research outputs found

    Evaluation of a numerical method to predict the polyphenol content in monovarietal olive oils

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    Three monovarietal virgin olive oils obtained from olives grown under biological agricultural system, in Portugal, with different ripening stages, were studied in what concerns the parameters usually related with oxidation status (total polyphenols, tocopherols, chlorophylls and carotenoids, peroxide values, oxidative stability, specific extinction coefficients K232 and K270 and titratable acidity). A total of 18 samples were analyzed: seven from Cv. Cobranc¸osa (maturation indices 1–7), five from Cv. Madural (maturation indices 3–7) and six from Cv. Verdeal Transmontana (maturation indices 1–6). Oxidative stability and polyphenols profile presented high correlation coef- ficients. Given this high correlation, a numerical method was developed and evaluated to predict total polyphenols contents in olive oil. The method is based on the kinetic equation of the oxidation process in the presence of antioxidants and on Rancimat profiles. Total polyphenols contents obtained with this method were similar to those obtained by the Folin-Ciocalteau method

    Qual a escala que melhor explica a composição das comunidades avifaunísticas numa área agro-florestal na envolvente de Évora?

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    O objectivo deste trabalho consistiu em testar diferentes escalas de abordagem com o intuito de verificar qual a que permite obter melhores correlações entre a composição das comunidades de aves nidificantes e a estrutura de uso

    A Note On Asymptotic Smoothness Of The Extensions Of Zadeh

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    The concept of asymptotic smooth transformation was introduced by J. Hale [10]. It is a very important property for a transformation between complete metric spaces to have a global attractor. This property has also consequences on asymptotic stability of attractors. In our work we study the conditions under which the Zadeh's extension of a continuous map f : R n → R n is asymptotically smooth in the complete metric space JF(R n) of normal fuzzy sets with the induced Hausdorff metric d ∞ (see Kloeden and Diamond [8]).212141153Barros, L.C., Bassanezi, R.C., Tonelli, P.A., On the continuity of Zadeh's extension (1997) Proceedings Seventh IFSA World Congress, 2, pp. 3-8. , PragueBarros, L.C., Bassanezi, R.C., Tonelli, P.A., Fuzzy modeling in populations dynamics (2000) Ecological Modeling, 128, pp. 27-33Brumley, W.E., On the asymptotic behavior of solutions of differential difference equations of neutral type (1970) J. of Differential Equations, 7, pp. 175-188Cabrelli, C.A., Forte, B., Molter, U., Vrscay, E., Iterated Fuzzy Sets Systems: A new approach to the inverse for fractals and other sets (1992) J. of Math. Anal, and Appl., 171, pp. 79-100Cooperman, G., (1978) α-Condensing Maps and Dissipative Processes, , Ph. D. Thesis, Brown University, Providence, R. IDiamond, P., Chaos in iterated fuzzy systems (1994) J. of Mathematical Analysis and Applications, 184, pp. 472-484Diamond, P., Time Dependent Differential Inclusions, Cocycle Attractors and Fuzzy Differential Equations (1999) IEEE Trans. on Fuzzy Systems, 7, pp. 734-740Diamond, P., Kloeden, P., (1994) Metric Spaces of Fuzzy Sets: Theory and Applications, , World Scientific PubFriedmann, M., Ma, M., Kandel, A., Numerical solutions of fuzzy differential and integral equations (1999) Fuzzy Sets and Systems, 106, pp. 35-48Hale, J.K., Asymptotic Behavior of Dissipative Systems (1988) Math. Surveys and Monographs, 25. , American Mathematical Society, ProvidenceHüllermeier, E., An Approach to Modeling and Simulation of Uncertain Dynamical Systems (1997) J. Uncertainty, Fuzziness, Know Ledge-Bases Syst., 5, pp. 117-137Kloeden, P.E., Fuzzy dynamical systems (1982) Fuzzy Sets and Systems, 7, pp. 275-296Kloeden, P.E., Chaotic iterations of fuzzy sets (1991) Fuzzy Sets and Systems, 42, pp. 37-42Nguyen, H.T., A note on thé extension principle for fuzzy sets (1978) J. Math. Anal. Appl., 64, pp. 369-380Puri, M.L., Ralescu, D.A., Fuzzy Random Variables (1986) J. of Mathematical Analysis and Applications, 114, pp. 409-422Roman-Flores, H., Barros, L.C., Bassanezzi, R., A note on Zadeh's Extensions (2001) Fuzzy Sets and Systems, 117, pp. 327-331Roman-Flores, H., On the Compactness of E(X) (1998) Appl. Math. Lett., 11, pp. 13-17Zadeh, L.A., Fuzzy sets (1965) Inform. Control, 8, pp. 338-35

    Ictiofauna De Riachos Da Bacia Do Baixo Rio Iguaçu, Estado Do Paraná, Brasil

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    The drainages of the Iguaçu River basin, as well as the main channel of the river, have peculiar characteristics resulting from geomorphological processes in this area, including the formation of the Iguaçu River Falls. This slope in the lower portion of the basin is a biogeographical barrier to many organisms. In this study was inventoried the fish fauna of streams of the lower Iguaçu River basin, evaluating possible differences in the species composition upstream and downstream of this biogeographical barrier. Sampling were conducted between 2004 and 2013, in five streams, three upstream and two downstream of the Iguaçu River Falls, using electrofishing. The nMDS analysis was run to investigate possible groupings of similar fauna between the streams sampled. The scores of this test were tested as to the significance of groupings with the Hotelling T2 test. The indicator value method (IndVal) was used to detect the distribution of species among the groups of the streams upstream and downstream of the Iguaçu River Falls. We collected 18,908 individuals of six orders, 11 families, and 40 species. Siluriformes and Characiformes had the highest species richness; Cyprinodontiformes presented the highest abundance. Considering the species recorded, 21 are considered natives to the Iguaçu River basin, including 15 endemic, wich were found only in streams upstream of the falls. Additional 18 species were verified only in the streams downstream of such barrier. Four species were common to both stretches. The axis 1 of the nMDS separated two groups: streams upstream (S1, S2 and S3) and streams downstream of the Iguaçu River Falls (S4 and S5). The indicator species analysis also indicated a distinction between the groups of streams, that were significantly different (Hotelling’s T2 = 234.36, p < 0.0001). The number of endemic species in the streams upstream of the Falls (15 spp.) evidences a significant effect of isolation promoted by the Iguaçu River Falls, and confirms the role of this barrier in the vicariant processes and endemism typical of this basin. These results emphasize the importance of conserving these ecosystems, once the extinction of species in this region means the irreversible loss of them. © 2016, Universidade Estadual de Campinas UNICAMP. All rights reserved.16311

    Chemometric characterization of three varietal olive oils (Cvs. cobrancosa, madural and verdeal Transmontana) extracted from olives with different maturation indices

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    This paper evaluates the usefulness of three chemical parameters (compositions on tocopherols, sterols and fatty acids) as a tool to discriminate three varietal olive oils (Cvs. Cobrançosa, Madural and Verdeal Transmontana), which are permitted cultivars for the production of ‘‘Trás-os-Montes olive oil’’, a Portuguese protected designation of origin (PDO) product. The olives were collected during the year crop 2000/2001 from the same orchard, in order to eliminate the geographical and climatic influences. Lots with different maturation indices were prepared to allow the evaluation of the ripening stage on the characteristics of varietal olive oils produced from each cultivar. Statistical methods such as multivariate analysis of variance (MANOVA), principal components analysis (PCA) and cluster analysis were used to evaluate significant differences on the studied parameters. Regarding the results, the three cultivars were clearly discriminated

    Does hepatocellular carcinoma in non-alcoholic steatohepatitis exist in cirrhotic and non-cirrhotic patients?

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    Non-alcoholic steatohepatitis (NASH) has been associated with hepatocellular carcinoma (HCC) often arising in histologically advanced disease when steatohepatitis is not active (cryptogenic cirrhosis). Our objective was to characterize patients with HCC and active, histologically defined steatohepatitis. Among 394 patients with HCC detected by ultrasound imaging over 8 years and staged by the Barcelona Clinic Liver Cancer (BCLC) criteria, we identified 7 cases (1.7%) with HCC occurring in the setting of active biopsy-proven NASH. All were negative for other liver diseases such as hepatitis C, hepatitis B, autoimmune hepatitis, Wilson disease, and hemochromatosis. The patients (4 males and 3 females, age 63 ± 13 years) were either overweight (4) or obese (3); 57% were diabetic and 28.5% had dyslipidemia. Cirrhosis was present in 6 of 7 patients, but 1 patient had well-differentiated HCC in the setting of NASH without cirrhosis (fibrosis stage 1) based on repeated liver biopsies, the absence of portal hypertension by clinical and radiographic evaluations and by direct surgical inspection. Among the cirrhotic patients, 71.4% were clinically staged as Child A and 14.2% as Child B. Tumor size ranged from 1.0 to 5.2 cm and 5 of 7 patients were classified as early stage; 46% of all nodules were hyper-echoic and 57% were <3 cm. HCC was well differentiated in 1/6 and moderately differentiated in 5/6. Alpha-fetoprotein was <100 ng/mL in all patients. HCC in patients with active steatohepatitis is often multifocal, may precede clinically advanced disease and occurs without diagnostic levels of alpha-fetoprotein. Importantly, HCC may occur in NASH in the absence of cirrhosis. More aggressive screening of NASH patients may be warranted

    Avaliação do impacte de fogos florestais em recursos hídricos subterrâneos

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    Comunicação apresentada no Seminário sobre Águas Subterrâneas, organizado pela Associação Portuguesa de Recursos Hídricos, que decorreu de 1 a 2 de Março de 2007 em Lisboa.Apresentam-se os objectivos, as tarefas e os primeiros resultados obtidos do Projecto actualmente em curso “Avaliação do impacte de fogos florestais nos recursos hídricos subterrâneos” (POCI/AGR/59180/2004). Os objectivos principais deste Projecto são estudar o impacte dos fogos nas quantidades de água envolvidas nos diversos processos do ciclo hidrológico e estudar o impacte das substâncias poluentes existentes nas cinzas florestais, no solo e no meio hídrico subterrâneo. Criou-se uma rede de monitorização da piezometria e da qualidade da água, e seleccionaram-se pontos de amostragem de solos e de cinzas em quatro áreas ardidas e não ardidas no concelho de Mação, para caracterizar e avaliar a influência que os fogos florestais têm na potencial degradação das Associação Portuguesa dos Recursos Hídricos 2 águas de superfície e subterrâneas. As áreas seleccionadas foram: bacia do Caratão, bacia do Carvoeiro, Bacia da Quebrada e Penhascoso. Para estas áreas estuda-se o coberto vegetal, os solos, a hidrogeologia, o clima e as condições de escoamento. Tem sido feita a monitorização dos níveis de água em furos e poços, assim como a amostragem de água para análise físico-química dos iões maiores e dos hidrocarbonetos aromáticos policíclicos (HAP). Para os solos, cinzas e lixiviados são analisados os seguintes elementos: Al, Ca, Fe, K, Na, Mg, Cd, Cu, Cr, Mn, Ni, Pb, Zn, Hg, S, C, H, N, e HAP. Para as bacias do Caratão e do Carvoeiro foi feito o inventário fitosociológico, comportando os aspectos fisiográficos, de geologia, de hidrologia e de vegetação (considerando 23 espécies), tendo-se desenvolvido a análise estatística dos dados, e foi feita a caracterização pedológica quanto aos parâmetros pH, matéria orgânica, P e K. Nas mesmas bacias foi feita a recolha de material vegetal para incineração em instalação de combustão, existindo já resultados analíticos para cinzas de arbustos e respectivos lixiviados

    Desenvolvimento de uma metodologia para avaliação de impactos qualitativos dos fogos nas águas subterrâneas : aplicação aos casos de estudo do Vale de Manteigas e de Mação

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    No Projecto POCI/AGR/59180/2004, concluído em 2009 (cf. Lobo-Ferreira et al., 2009), apresenta-se uma metodologia para avaliação quantitativa dos impactos dos fogos florestais na quantidade e qualidade das águas superficiais e subterrâneas. Nesta metodologia procura-se avaliar as alterações que possam ter ocorrido após o fogo: (A) em volumes de recarga, (B) volumes de escoamento superficial, (C) qualidade das águas superficiais e subterrâneas. Esta metodologia considera: (1) tipo e densidade de coberto vegetal à data do incêndio; (2) tipos de poluentes que podem ser libertados pelas diferentes comunidades vegetais afectadas pelo fogo; (3) extensão e volume do aquífero e sua porosidade eficaz, para aferir dos volumes de reservas de água; (4) recarga média anual; (5) tempo de permanência das águas no sistema subterrâneo. Para a avaliação do tipo e densidade de coberto vegetal e consequente biomassa combustível à data do incêndio usou-se a inventariação fitossociológica, cartografia da vegetação, análise estatística multivariada e estimativa da biomassa florestal ardida, realizada pelo Instituto Politécnico de Castelo Branco-Escola Superior Agrária. Os tipos e cargas poluentes libertados calcularam-se com base nos valores de biomassa ardida e estudos (realizados por INETI – Departamento de Engenharia Energética e Controlo Ambiental) de cinzas de ensaios de combustão de espécies florestais e arbustivas representativas do coberto vegetal ardido, e ensaios de lixiviação de solos e cinzas. A avaliação das variações na recarga baseou-se na informação recolhida nos estudos quantitativos realizados na bacia de Manteigas, associada a modelos hidrológicos conceptuais e cenários de variação de escoamento e evapotranspiração quando a informação não era suficiente para colmatar as lacunas de conhecimento. Com base na biomassa ardida, características composicionais das suas cinzas e potenciais de lixiviação, calculou-se a quantidade e tipo de poluentes em fase sólida e dissolvida passíveis de entrar nas águas superficiais e subterrânea. As características hidráulicas dos meios geológicos afectados deram os volumes de armazenamento e as prováveis velocidades de circulação nestes materiais, o que serviu para prever espaços temporais de contaminação da área. Da avaliação dos volumes de carga poluente calculados e dos dados de campo de decaimento destas cargas poluentes nas águas superficiais e subterrâneas em zonas de coberto vegetal similar estabeleceram-se cenários possíveis do tempo de desaparição do poluente na área ardida. Nesta comunicação realçam-se os aspectos relacionados com a qualidade das águas subterrâneas

    Carrot seed production under different soil moisture regimes

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    Objetivando estabelecer tensões de água no solo que mais favoreçam a produção de sementes de cenoura (Daucus carora L.), foram conduzidos experimentos no CNPH, em Brasília, DF, nos anos de 1984, 1985 e 1986. Os tratamentos consistiram em irrigar quando as tensões, na profundidade de 10 cm até o florescimento e de 20 cm após este estádio, atingiam 25, 50, 100, 200,400, 800 e 1.500 kPa. A análise de regressão indicou que a produtividade máxima de sementes foi obtida com a tensão de 75 kPa, enquanto a tensão ótima econômica foi estimada cm 80 kPa. O estande, a taxa de germinação e o peso de 1.000 sementes não foram influenciados pelas diferentes tensões.Field experiments were carried out at CNPH-EMBRAPA in 1984, 1985, and 1986 with the objective of establishing soil moisture management for carrot (Daucus carota L.) seed production, based on soil water tension. Treatments consisted of refilling the root zone with water as soil water tension reached values of 25, 50, 100, 200, 400, 800 and 1.500 kPa, at 10 cm depth till flowering and at 20 cm depth after that phase. Regression analysis allowed to conclude that maximum seed productivity was obtained when irrigation was applied each time soil water tension reached 75 kPa. Economical water tension was found to be 80 kPa. Stand, germination and weight of 1.000 seeds were found not to be significantly influenced by the treatment
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