997 resultados para Potencial gravitacional


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Eryngium foetidum L., Eryngium cf. campestre and Coriandrum sativum L. are Apiaceae family vegetable appreciated due to its peculiar flavor and consumed mainly in the north and northeast of Brazil. The vegetables are rich in protein, vitamins, fiber, minerals, total phenolics and other essential bioactives for a balanced health. Nevertheless, many vegetables are falling into disuse by the population, instead of processed foods. The rescue consumption of these species is very important, aiming at their nutritional, therapeutic and antioxidant benefits. In this study, was quantified the levels of total phenolic, flavonoids and dihidroflavonoides by molecular absorption spectrophotometry in the ultraviolet. The total antioxidant capacity was also evaluated using five methodologies of in vitro assays: test Total Antioxidant Capacity (TAC), scavenging of DPPH and ABTS radical, Power Reducing and Power Chelating. It was also evaluated the power inhibitor of α-amylase and lipoxygenase extracts. All species showed significant levels of total phenolics, flavonoids and dihidroflavonoides in its composition. All treatments showed antioxidant activity of 50% except the sheets of E. cf. campestre, C. sativum and bracts of E. foetidum in DPPH and bracts of E. foetidum in ABTS. All treatments also exhibited 50% inhibition activity of the enzyme lipoxygenase.In α-amylase only the leaves of E. cf. campestre and C. sativum showed IC50. It was evaluate the phytochemical composition, aiming to meet the nutritional potential of Apiaceae family vegetables, called unconventional: Eryngium foetidum L., Eryngium cf. campestre; and conventional: Coriandrum sativum L. At the centesimal composition analysis Coriandrum sativum L. presented the highest levels of protein. The leaves of Eryngium foetidum L. exhibited higher values than other species in dietary fiber, while Eryngium cf. campestre detach with superior results in lipids. About the analyzed minerals, the leaves of Eryngium cf. campestre expressed results superior to the other in N, Ca, Mg, S and Cu. The amount of iron highlighted in sheets of E. foetidum, whereas P, K, Mn, Zn and B were most significant on leaves of C. sativum. It was concluded that the levels of total phenolic compounds found in these vegetables, characterize them for its high potential in the antioxidant and inhibition of lipoxygenase and α-amylase enzymes. Their protein and mineral levels classify them as species that can be used as a nutritional source in the preparation of other foods and may their regular consumption bring benefit to human health.

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Despite tobacco being a culture propagated by seeds, there is little information concerning tests that allow the distinction of similar germination lots in different levels of vigor. The diversity of cultivars available in the market, and a few peculiarities of the species, such as uneven maturation of the flowers, fruits and seeds, small size and seed dormancy, are considered obstacles for obtaining lots of tobacco of high physiological potential. Thus, this research was developed with the objective of adapting feasibility and vigor tests for evaluating the physiological potential of tobacco seed lots. We used nine lots of tobacco seeds of cultivar CSC 447 and nine lots of seeds of cultivar BAT 2101, belonging to variety groups Virginia and Burley, respectively. Initially, germination test was conducted to characterize the profile of the lots. For determining the feasibility and vigor of the tobacco seeds, germination tests were conducted in distinct temperatures, controlled emergence conditions, electric conductivity, artificial aging and in tetrazolium. For determining the isoenzymatic marker for seed quality, analyses were conducted with enzymes catalase, esterase, malate dehydrogenase and alcohol dehydrogenase. In conclusion, the emergence tests at 25oC and artificial aging at 41oC for 72 hours, are efficient in discriminating the lots of tobacco seeds in different levels of vigor. The electric conductivity and germination tests in different temperatures have distinct responses in relation to the genotype of the tobacco seeds. The tetrazolium test using the methodology with pre-conditioning in 3.5% sodium hypochlorite solution and subsequent emersion in 1.0% tetrazolium solution for 18 hours is efficient for the quick evaluation of the feasibility of tobacco seeds. The analysis of the profiles of enzymes catalase, esterase, malate dehydrogenase and alcohol dehydrogenase is efficient as markers for tobacco seed quality.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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A literatura sobre os determinantes do desempenho exportador das firmas industriais é ampla e bem diversificada, tanto na metodologia como nos resultados encontrados Para o caso dos países em desenvolvimento, em particular, a identificação destes determinantes não é tão convergente no sentido de que as relações de causalidade não são claras no que toca à sua direção e à relevância de determinada relação para um país específico. As relações comumente testadas no nível da firma industrial para estes países são as entre exportações e origem do capital (em particular, firmas estrangeiras), inovação e exportações, tamanho, produtividade e exportações, intensidade tecnológica setorial e exportações, eficiência de escala e exportações, indicadores de desempenho, custos fixos, freqüência das exportações e desempenho exportador. Os trabalhos mais recentes no Brasil têm focalizado mais o papel da eficiência de escala como determinante das exportações e o impacto das empresas transnacionais sobre o comércio exterior. Um passo metodológico à frente foi o uso das técnicas de Propensity Score Matching (PSM) para identificar as firmas potencialmente exportadoras, ou seja, firmas não exportadoras que possuem características produtivas e tecnológicas semelhantes a firmas exportadoras, o que contribui para trazer novas luzes à formulação de uma política industrial e tecnológica para o comércio exterior, pois vai além das proposições de reforçar as firmas exportadoras já existentes, ampliando o foco das políticas para exportadores potenciais. O objetivo aqui é trazer uma dimensão espacial do potencial exportador das firmas industriais brasileiras, através da análise das seguintes questões: (1) existe ou não um padrão locacional das firmas industriais que possuem probabilidade de exportar, isto é, das firmas com algum potencial exportador, seja este realizado ou não?; (2) existem determinantes espaciais das firmas com potencial exportador?; (3) existem determinantes espaciais específicos para as firmas com potencial exportador não realizado?

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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En este trabajo se efectúan mediciones, comparables con las metodologías internacionales, sobre la incidencia distributiva del impuesto a la renta y las transferencias públicas monetarias en 17 países de América Latina. Los resultados indican que la política fiscal juega un papel limitado en mejorar la distribución del ingreso disponible; el coeficiente de Gini baja apenas tres puntos porcentuales luego de la acción fiscal directa. En promedio, el 61% de esta reducción proviene de las transferencias públicas en efectivo y el resto de los tributos directos, reflejo del imperativo de fortalecer el impuesto a la renta personal. Las mediciones de encuestas de hogares permiten simular los efectos potenciales de reformas tributarias orientadas a aumentar las tasas medias efectivas del decil superior. Si esta recaudación adicional se destina a transferencias focalizadas, los efectos son muy significativos. En consecuencia, es necesario evaluar las reformas tributarias considerando el uso de estos recursos.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)