995 resultados para green function


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The close relationship between the chlorophyll-meters readings and the total chlorophyll and nitrogen contents in leaves, has allowed their evaluation both in annual and perennial species. Besides, some physiological events such as the CO2 assimilation have also been estimated by chlorophyll meters. This work was carried out aiming to evaluate the gas exchanges of peach palms as a function of the chlorophyll SPAD-Meter readings. Three year-old peach palms from Yurimaguas, Peru were studied in Ubatuba, SP, Brazil, spaced 2 x 1 m in area under a natural gradient of organic matter which allowed four plots to be considered, according to the peach palms leaves colors, from light yellow to dark green. The SPAD readings and the stomatal frequency of leaflets were evaluated. The photosynthetic photon flux density (PPFD, μmol m-2 s-1), the leaf temperature (Tleaf, ºC), the CO2 assimilation (A, μmol m-2 s-1), the stomatal conductance (g s, mol m-2 s-1), the transpiration (E, mmol m-2 s-1) and the intercellular CO2 concentration (Ci, μmol mol-1) were evaluated with a portable infrared gas analyzer (LCA-4, ADC BioScientific Ltd., Great Amwell, U.K.). A linear increase in the CO2 assimilation as a function of the SPAD readings (y = -0.34 + 0.19x, R² = 0.99), indicates that they can be a rapid and cheap complementary method to evaluate in peach palms some important physiological events, such as CO2 assimilation.

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The aim of this study was to identify the relation between the evapotranspirometer demand and the supply of water from local rainfall, evaluating the possibility of using water excess for irrigation of Green Roofs in the State of Mato Grosso, in Brazil. The study was done using a series of historical data provided by the National Institute of Meteorology (INMET - Instituto Nacional de Meteorologia) which has official climatological stations in 12 cities and regions of the State. The evapotranspiration values were obtained by the Penman-Monteith method and by the Climatic Water Balance (CWB) by the Thornthwaite and Mather method using Available Water Capacity (AWC) of 12mm. With the CWB the excess and deficit were calculated, which were used for the estimative of the volume and area of a reservoir as a function of a collector area of a roof of 100m² and the volume of supplementary water for irrigation. With the obtained results, it was found that in most investigated regions of the State the use of green roofs is not compromised by the water deficiency. On the other hand, the use of a reservoir to accumulate the rain water excess may be impractical, because it requires a considerable area for installation and also because of the high cost of the land.

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Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

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The Zubarev equation of motion method has been applied to an anharmonic crystal of O( ,,4). All possible decoupling schemes have been interpreted in order to determine finite temperature expressions for the one phonon Green's function (and self energy) to 0()\4) for a crystal in which every atom is on a site of inversion symmetry. In order to provide a check of these results, the Helmholtz free energy expressions derived from the self energy expressions, have been shown to agree in the high temperature limit with the results obtained from the diagrammatic method. Expressions for the correlation functions that are related to the mean square displacement have been derived to 0(1\4) in the high temperature limit.

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This research quantitatively evaluates the water retention capacity and flood control function of the forest catchments by using hydrological data of the large flood events which happened after the serious droughts. The objective sites are the Oodo Dam and the Sameura Dam catchments in Japan. The kinematic wave model, which considers saturated and unsaturated sub-surface soil zones, is used for the rainfall-runoff analysis. The result shows that possible storage volume of the Oodo Dam catchment is 162.26 MCM in 2005, while that of Samerua is 102.83 MCM in 2005 and 102.64 MCM in 2007. Flood control function of the Oodo Dam catchment is 173 mm in water depth in 2005, while the Sameura Dam catchment 114 mm in 2005 and 126 mm in 2007. This indicates that the Oodo Dam catchment has more than twice as big water capacity as its capacity (78.4 mm), while the Sameura Dam catchment has about one-fifth of the its storage capacity (693 mm).

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It is widely recognized that gain- and loss-of-function approaches are essential for understanding the functions of specific genes, and such approaches would be particularly valuable in studies involving human embryonic stem (hES) cells. We describe a simple and efficient approach using lipofection to transfect hES cells, which enabled us to generate hES cell lines expressing naturally fluorescent green or red proteins without affecting cell pluripotency. We used these cell lines to establish a means of diminishing gene function using small interfering (si)RNAs, which were effective at knocking down gene expression in hES cells. We then demonstrated that stable expression of siRNA could knock down the expression of endogenous genes. Application of these gain- and loss-of-function approaches should have widespread use, not only in revealing the developmental roles of specific human genes, but also for their utility in modulating differentiation.

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The beneficial effects of green tea catechins, such as the proposed improvement in endothelial function, may be influenced by phase II metabolism during and after absorption. The methylation enzyme, catechol-O-methyltransferase (COMT), has a missense mutation rs4680 (G to A), proposed to result in a 40 % reduction in enzyme activity. In the present pilot study, twenty subjects (ten of each homozygous COMT genotype) were recruited. Green tea extract capsules (836 mg green tea catechins) were given in a fasted state, and a high-carbohydrate breakfast was given after 60 min. Blood samples and vascular function measurements were taken at regular intervals. The change in digital volume pulse stiffness index (SI) from baseline was shown to be different between genotype groups at 120 and 240 min, with a lower SI in the GG individuals (P ≤ 0·044). The change in blood pressure from baseline also differed between genotype groups, with a greater increase in systolic (P = 0·023) and diastolic (P = 0·034) blood pressure at 120 min in the GG group. The AA group was shown to have a greater increase in insulin concentrations at 120 min (P = 0·019) and 180 min (P = 0·008) compared with baseline, despite similar glucose profiles. No genotypic differences were found in vascular reactivity measured using laser Doppler iontophoresis, total nitrite, lipids, plasma total antioxidant capacity or inflammatory markers after ingestion of the green tea extract. In conclusion, SI and insulin response to the glucose load differed between the COMT genotype groups, and this may be suggestive of a green tea extract and genotype interaction.

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Since the advent of the postgenomic era, efforts have focused on the development of rapid strategies for annotating plant genes of unknown function. Given its simplicity and rapidity, virus-induced gene silencing (VIGS) has become one of the preeminent approaches for functional analyses. However, several problems remain intrinsic to the use of such a strategy in the study of both metabolic and developmental processes. The most prominent of these is the commonly observed phenomenon of ""sectoring"" the tissue regions that are not effectively targeted by VIGS. To better discriminate these sectors, an effective marker system displaying minimal secondary effects is a prerequisite. Utilizing a VIGS system based on the tobacco rattle virus vector, we here studied the effect of silencing the endogenous phytoene desaturase gene (pds) and the expression and subsequent silencing of the exogenous green fluorescence protein (gfp) on the metabolism of Arabidopsis (Arabidopsis thaliana) leaves and tomato (Solanum lycopersicum) fruits. In leaves, we observed dramatic effects on primary carbon and pigment metabolism associated with the photobleached phenotype following the silencing of the endogenous pds gene. However, relatively few pleiotropic effects on carbon metabolism were observed in tomato fruits when pds expression was inhibited. VIGS coupled to gfp constitutive expression revealed no significant metabolic alterations after triggering of silencing in Arabidopsis leaves and a mild effect in mature green tomato fruits. By contrast, a wider impact on metabolism was observed in ripe fruits. Silencing experiments with an endogenous target gene of interest clearly demonstrated the feasibility of cosilencing in this system; however, carefully constructed control experiments are a prerequisite to prevent erroneous interpretation.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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The content of ascorbic acid was assayed in acerolas harvested in three phases of maturation: green-yellow fruits (I); light red (II) and wine-coloured (III). Phase I and Phase II fruit were packed in aluminium sheets and stoppered flasks and stored in freezer (-10o.C) and in refrigerator (8o.C). Samples of 8 fruits from each experimental condiction were analysed for ascorbic acid determination by 2-chlorophenol indophenol discolouration method. The averages of 1.393,5 mg./100g. for Phase I sample, 1024,9 for Phase II and 756,5 for Phase III fruits, showed a statistically significative linear decreasing of the ascorbic acid content related with the maturation extent Phase I samples stored in freezing showed statitically significative decreasing of that vitamin at 408 hours of storage in both: aluminium sheet and stoppered flask package; in chilling temperature there was significative reduction of ascorbic acid content after 240 and 312 hours, respectively, for fruits packed in aluminium sheet and stopped flasks. Phase Il samples showed significative lost at 72 hours of storage when maintained in freezing temperature either, in aluminium sheet or in stoppered flasks: When stored in chilling temperature showed progressive lost of ascorbic acid in all measuring periods in every package. After 144 hours suffered deterioration suggested by colour changes.

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Pomegranate (PGE) and green tea (GTGE) glycolic extracts are being employed in formulations because of their antiseptic and astringent effects. Apricot (AGE) glycolic extract possesses function cooling and antibacterial. The aim was to verify the antibacterial activity of these extracts incorporated in gel base. The antibacterial activity was verified by diffusion in agar method, using cylinder in plate. Plates containing Staphylococcus aureus (ATCC 6538p), Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 10536) and Salmonella sp. (ATCC 19196) were incubated at 37°C for 24 hours. After incubation, the results were analysed with a pachymeter, observing the bacterial growth inhibition halo diameter and the statistical significance level was determined. PGE presented activity only against P. aeruginosa; GTGE presented activity against S. aureus, P. aeruginosa and E. coli; and AGE presented activity against P. aeruginosa and Salmonella sp. According to the experimental conditions, it is possible to conclude that GTGE presented the greater growth inhibition halo diameter when compared with other extracts, suggesting higher antibacterial action of this extract.

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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)

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Este trabalho oferece um método para a predição da intensidade de campo elétrico para TV Digital utilizando a Função de Green diádica. A Diádica é uma ferramenta matemática eficiente que tem simplicidade simbólica e robustez permitindo, assim, que algumas características do meio (como permissividade, condutividade e permeabilidade, por exemplo) sejam consideradas na elaboração do modelo de campo elétrico, bem como levar em conta a anisotropia do meio. Na maior parte dos trabalhos correlatos, que utilizam as funções de Green diádicas, estão relacionados na faixa de VHF. Este trabalho irá apresentar desde os conceitos básicos das diádicas, desenvolvendo-a para o cálculo de um modelo que permita predizer o campo elétrico para a faixa de UHF, na qual os sistemas de TV Digital se encontram. Uma explanação teórica e um desenvolvimento matemático serão feitos de forma que um entendimento claro e objetivo sejam alcançados no estudo das funções de Green diádicas, numa parte da teoria do eletromagnetismo. Testes foram realizados para confirmar a aplicabilidade da formulação sugerida, fazendo simulações que realizem uma comparação entre os dados medidos, de duas emissoras de TV situadas na cidade de Belém, e o modelo de Okumura-Hata modificado, mostrando resultados satisfatórios, tanto para frequências na faixa de VHF e UHF.