992 resultados para 13077-070
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In [H. Brezis, A. Friedman, Nonlinear parabolic equations involving measures as initial conditions, J. Math. Pure Appl. (9) (1983) 73-97.] Brezis and Friedman prove that certain nonlinear parabolic equations, with the delta-measure as initial data, have no solution. However in [J.F. Colombeau, M. Langlais, Generalized solutions of nonlinear parabolic equations with distributions as initial conditions, J. Math. Anal. Appl (1990) 186-196.] Colombeau and Langlais prove that these equations have a unique solution even if the delta-measure is substituted by any Colombeau generalized function of compact support. Here we generalize Colombeau and Langlais` result proving that we may take any generalized function as the initial data. Our approach relies on recent algebraic and topological developments of the theory of Colombeau generalized functions and results from [J. Aragona, Colombeau generalized functions on quasi-regular sets, Publ. Math. Debrecen (2006) 371-399.]. (C) 2009 Elsevier Ltd. All rights reserved.
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Flow injection analysis (FIA) with amperometric detection was employed for the quantification of N-acetylcysteine (NAC) in pharmaceutical formulations, utilizing an ordinary pyrolytic graphite (OPG) electrode modified with cobalt phthalocyanine (CoPc). Cyclic voltammetry was used in preliminary studies to establish the best conditions for NAC analysis. In FIA-amperometric experiments the OPG-CoPc electrode exhibited sharp and reproducible current peaks over a wide linear working range (5.0 x 10(-5)-1.0 x 10(-3) mol L(-1)) in 0.1 mol L(-1) NaOH solution. High sensitivity (130 mA mol(-1) cm(2)) and a low detection limit (9.0 x 10(-7) mol L(-1)) were achieved using the sensor. The repeatability (R.S.D.%) for 13 successive flow injections of a solution containing 5.0 x 10(-4) mol L(-1) NAC was 1.1%. The new procedure was applied in analyses of commercial pharmaceutical products and the results were in excellent agreement with those obtained using the official titrimetric method. The proposed amperometric method is highly suitable for quality control analyses of NAC in pharmaceuticals since it is rapid, precise and requires much less work than the recommended titrimetric method. (C) 2010 Elsevier B.V. All rights reserved.
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Sulfinyltoluquinones (2a-2c) were submitted to thermal or catalyzed [4+2] cycloaddition reactions with cyclopentadiene. For p-tolylsulfinyltoluquinones (2b) and (2c), almost complete C2-C3-chemo- and unlike-diastereoselectivity was achieved by catalysis with ZnBr(2), yielding adducts 6. Under thermal conditions, Diels-Alder reaction took place at the C5-C6 double bonds of quinones 2a-2c, generating mixtures of diastereoisomeric like- and unlike-adducts 4.
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The effect of variations in the composition for ternary catalysts of the type Pt-x(Ru-Ir)(1-x)/C on the methanol oxidation reaction in acid media for x values of 0.25, 0.50 and 0.75 is reported. The catalysts were prepared by the sol-gel method and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), atomic absorption spectroscopy (AAS) and energy dispersive X-ray (EDX) analyses. The nanometric character (2.8-3.2 nm) of the sol-gel deposits was demonstrated by XRD and TEM while EDX and AAS analyses showed that the metallic ratio in the compounds was very near to the expected one. Cyclic voltammograms for methanol oxidation revealed that the reaction onset occur at less positive potentials in all the ternary catalysts tested here when compared to a Pt-0.75-Ru-0.25/C (E-Tek) commercial composite. Steady-state polarization experiments (Tafel plots) showed that the Pt-0.25(Ru-Ir)(0.75)/C catalyst is the more active one for methanol oxidation as revealed by the shift of the reaction onset towards lower potentials. In addition, constant potential electrolyses suggest that the addition of Ru and Ir to Pt decreases the poisoning effect of the strongly adsorbed species generated during methanol oxidation. Consequently, the Pt-0.25 (Ru-Ir)(0.75)/C Composite catalyst is a very promising one for practical applications. (c) 2007 Elsevier B.V. All rights reserved.
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BACKGROUND: Whether the type of dietary fat could alter cardiometabolic responses to a hypercaloric diet is unknown. In addition, subclinical cardiometabolic consequences of moderate weight gain require further study. METHODS AND RESULTS: In a 7-week, double-blind, parallel-group, randomized controlled trial, 39 healthy, lean individuals (mean age of 27±4) consumed muffins (51% of energy [%E] from fat and 44%E refined carbohydrates) providing 750 kcal/day added to their habitual diets. All muffins had identical contents, except for type of fat; sunflower oil rich in polyunsaturated fatty acids (PUFA diet) or palm oil rich in saturated fatty acids (SFA diet). Despite comparable weight gain in the 2 groups, total: high-density lipoprotein (HDL) cholesterol, low-density lipoprotein:HDL cholesterol, and apolipoprotein B:AI ratios decreased during the PUFA versus the SFA diet (-0.37±0.59 versus +0.07±0.29, -0.31±0.49 versus +0.05±0.28, and -0.07±0.11 versus +0.01±0.07, P=0.003, P=0.007, and P=0.01 for between-group differences), whereas no significant differences were observed for other cardiometabolic risk markers. In the whole group (ie, independently of fat type), body weight increased (+2.2%, P<0.001) together with increased plasma proinsulin (+21%, P=0.007), insulin (+17%, P=0.003), proprotein convertase subtilisin/kexin type 9, (+9%, P=0.008) fibroblast growth factor-21 (+31%, P=0.04), endothelial markers vascular cell adhesion molecule-1, intercellular adhesion molecule-1, and E-selectin (+9, +5, and +10%, respectively, P<0.01 for all), whereas nonesterified fatty acids decreased (-28%, P=0.001). CONCLUSIONS: Excess energy from PUFA versus SFA reduces atherogenic lipoproteins. Modest weight gain in young individuals induces hyperproinsulinemia and increases biomarkers of endothelial dysfunction, effects that may be partly outweighed by the lipid-lowering effects of PUFA. CLINICAL TRIAL REGISTRATION URL: http://ClinicalTrials.gov. Unique identifier: NCT01427140.
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Utilizando técnicas de geoprocessamento, desenvolveu-se metodologia para avaliar e diagnosticar os impactos ambientais decorrentes do uso e ocupação do solo em áreas de Florestas Nacionais. A área teste da pesquisa foi a Floresta nacional de Brasília. No modelamento para a avaliação da perda e tolerância de solo em função de seu uso, utilizou-se das ferramentas de geoprocessamento e imagem de satélite para a solução da equação USLE. Foi possível determinar as áreas de preservação permanente e as áreas passíveis de reflorestamento, através da criação de cenários de colheita florestal, bem como as diferentes formas de manejo que devem ser adotadas em função das perdas de solo por erosão laminar. As áreas de perda de solo acima de sua tolerãncia representam 1,90% (177,44 ha) da área total da Flona. As áreas consideradas de Preservação Permanente sob o aspecto da legislação vigente e do uso atual representam 6,78% (633,46ha) de sua área total. Destes, 140,18ha (22,13%) apresentam uma cobertura vegetal do tipo campo e devem ser recuperados e convertidos em áreas com cobertura vegetal do tipo floresta, a fim de adequar-se a legislação vigente como também minimizar os processos erosivos que possam comprometer os cursos d'água. A área passível de implantação de floresta corresponde a 8.712,82 ha (93,22%), onde 5.642,48 ha (64,76%) podem ser manejados a corte raso e 3.070,34 hectares (32,24%) devem ser manejados a corte seletivo, para que não haja comprometimento do solo devido às perdas por erosão laminar.
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Introdução: Pacientes com insuficiência cardíaca (IC) apresentam redução de força e resistência dos músculos inspiratórios. Objetivo: Avaliar os efeitos do treinamento muscular inspiratório sobre a capacidade funcional, oscilação da ventilação, e sobre a qualidade de vida na IC. Pacientes e Métodos: Foram selecionados 33 pacientes com IC, que apresentavam fraqueza da musculatura inspiratória. Os pacientes foram randomizados para participarem de um programa de treinamento muscular inspiratório (TMI) de 12 semanas, 7 sessões por semana de trinta minutos por sessão, com incremento semanal de 30% PImáx, com Threshold Inspiratory Muscle Trainer (grupo TMI, n=17) e um grupo controle (n=16), que realizaram o mesmo programa de treinamento, porém sem carga resistiva. Antes e após o TMI, foram avaliadas a força e a resistência da musculatura inspiratória, a capacidade funcional, a oscilação da ventilação durante o teste cardiopulmonar (TCP), e a qualidade de vida. Resultados: No grupo TMI houve aumento da PImáx (60,9±1,8 vs 129,6±2,8 cmH2O, ANOVA: p<0,001); da resistência, de 56,9±3 % para 65,5±2,9 %, (ANOVA: p<0,001); da distância percorrida no teste de caminhada, de 449,1±17,4 m para 550±17,2 m, (ANOVA: p<0,001) e no consumo de oxigênio no pico de exercício, de 17,2±0,5 para 20,6±0,7 ml/kg.min, (ANOVA: p<0,001). A oscilação da ventilação foi reduzida de 0,07±0,005 para 0,03±0,006 (ANOVA: p<0,001). Houve também melhora na qualidade de vida. Não houve alteração no grupo controle. Conclusão: O treinamento muscular inspiratório tem impacto sobre a musculatura ventilatória, melhorando a capacidade funcional em pacientes com insuficiência cardíaca.
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This article proposes a simple and sensitive HPLC method with photo-diode array detection for the analysis of organic acids, monomeric polyphenols and furanic compounds in wine samples by direct injection. The chromatographic separation of 8 organic acids, 2 furans and 22 phenolic compounds was carried out with a buffered solution (pH 2.70) and acetonitrile as mobile phases and a difunctionally bonded C18 stationary phase, Atlantis dC18 (250 4.6 mm, 5mm) column. The elution was performed in 12 min for the organic acids and in 60 min for the phenolic compounds, including phenolic acids, stilbenes and flavonoids. Target compounds were detected at 210 nm (organic acids, flavan-3-ols and benzoic acids), 254 nm (ellagic acid), 280 nm (furans and cinnamic acid), 315 nm (hydroxycinnamic acids and trans-resveratrol) and 360 nm (flavonoids). The RSD for the repeatability test (n55) of peak area and retention times were below 3.1 and 0.3%, respectively, for phenolics and below 1.0 and 0.2% for organic acids. The RSDs expressing the reproducibility of the method were higher than for the repeatability results but all below 9.0%. Method accuracy was evaluated by the recovery results, with averaged values between 80 and 104% for polyphenols and 97–105% for organic acids. The calibration curves, obtained by triplicate injection of standard solutions, showed good linearity with regression coefficients higher than 0.9982 for polyphenols and 0.9997 for organic acids. The LOD was in the range of 0.07–0.49 mg/L for polyphenols (cinnamic and gallic acids, respectively) and 0.001–0.046 g/L for organic acids (oxalic and lactic acids, respectively). The method was successfully used to measure and assess the polyphenolic fingerprint and organic acids profile of red, white, rose ´ and fortified wines.
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The flowering is a physiological process that it is vital for plants. This physiological process has been well studied in the plant model Arabidopsis, but in sugarcane this process is not well known. The transition of the shoot apical meristem from vegetative to flowering is a critical factor for plant development. At Brazil northeastern region, the transition to flowering in sugarcane has an important effect as it may reduce up to 60% its production. This is a consequence of the sugar translocation from stalks to the shoot apical meristem which is necessary during the flowering process. Therefore, the aim of this work was to explore and analyze cDNAs previously identified using subtractive cDNA libraries. The results showed that these cDNAs showed differential expression profile in varieties of sugarcane (early x late flowering). The in silico analysis suggested that these cDNAs had homology to calmodulin, NAC transcription factor and phosphatidylinositol, a SEC14, which were described in the literature as having a role in the process of floral development. To better understand the role of the cDNA homologous to calmodulin, tobacco plants were transformed with overexpression cassettes in sense and antissense orientation. Plants overexpressing the cassette in sense orientation did not flowered, while plants overexpressing the cassette in the antissense orientation produced flowers. The data obtained in this study suggested the possible role from CAM sequence, SEC14 and NAC in the induction/floral development pathway in sugarcane, this is the first study in order to analyze these genes in the sugarcane flowering process.
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A total of 58 Ucides cordatus (Linnaeus, 1763) ovigerous females in final embryonic stage were collected in mangrove forest at Iguape (São Paulo). Each female were kept in laboratory until the larvae hatching and had their carapace width (CW) measured with caliper (0.05 mm) and the larval number (LN) calculated by volumetric method. The hatching rates (HR) were calculated for each animal's size class (5 mm). The values of LN and CW obtained were subjected to regression analyses and the best fitting model was chosen by comparing the obtained determination coefficients (R²). The fertility varied from 71,200 to 220,800 larvae (147,169 ± 32,070 larvae), corresponding to 41.7 to 76.8 mm CW (63.7±7.9 mm), respectively. The relationship LNxCW was expressed by the equation LN = 284.1CW1.5º¹ (N = 58; R² = 0.74; p < 0.01), that showed a positive correlation between the variables. Most part of ovigerous females (89.7%) showed their hatching during the nightly period. A negative correlation between HR and CW was observed in these animals (p < 0.05), probably due to reduction of spermatophores in the seminal receptacle (multiparous females) or due to senility in the females with large size. The biological studies of U. cordatus are very important for practices adoption that preserve and make the rational use of this recourse in Brazilian's mangrove forests.
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O trabalho foi conduzido com o objetivo de determinar os períodos de interferência e de controle das plantas daninhas na cultura do arroz de terras altas. Os experimentos foram instalados nos anos agrícolas de 2003/04 e 2004/05 em área experimental da Universidade Estadual Paulista, campus de Jaboticabal/SP, situado a 21º 15' 22 de latitude sul e 48º 18' 58 de longitude oeste. O cultivar utilizado foi o IAC 202, semeado, respectivamente, em 18 de novembro de 2003 e 24 de novembro de 2004. O delineamento experimental foi em blocos ao acaso, com os tratamentos constituídos por períodos crescentes de controle ou de convivência das plantas daninhas com a cultura. Os períodos iniciais de controle ou de convivência após a emergência da cultura foram: 0-10, 0-20, 0-30, 0-40, 0-50, 0-60, 0-70 dias e 0-colheita. As principais plantas daninhas em 2003/04 foram Cyperus rotundus, Cenchrus echinatus, Digitaria spp. Echinochloa crus-galli e Brachiaria decumbens. No ano agrícola de 2004/05, destacaram-se Digitaria spp., C. echinatus, Raphanus raphanistrum e Alternanthera tenella. Considerando 5% de tolerância na redução da produtividade do arroz nos anos agrícolas de 2003/04 e 2004/05, concluiu-se que os períodos anteriores à interferência (PAI) foram de 12 e 26 DAE, respectivamente; os períodos totais de prevenção à interferência (PTPI), de 40 e 42 DAE; e os períodos críticos de prevenção à interferência (PCPI), de 12 a 40 DAE e de 26 a 42 DAE, respectivamente.
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O desenvolvimento de projetos relacionados ao desempenho de diversas culturas tem recebido aperfeiçoamento cada vez maior, incorporado a modelos matemáticos sendo indispensável à utilização de equações cada vez mais consistentes que possibilitem previsão e maior aproximação do comportamento real, diminuindo o erro na obtenção das estimativas. Entre as operações unitárias que demandam maior estudo estão aquelas relacionadas com o crescimento da cultura, caracterizadas pela temperatura ideal para o acréscimo de matéria seca. Pelo amplo uso dos métodos matemáticos na representação, análise e obtenção de estimativas de graus-dia, juntamente com a grande importância que a cultura da cana-de-açúcar tem para a economia brasileira, foi realizada uma avaliação dos modelos matemáticos comumente usados e dos métodos numéricos de integração na estimativa da disponibilidade de graus-dia para essa cultura, na região de Botucatu, Estado de São Paulo. Os modelos de integração, com discretização de 6 em 6 h, apresentaram resultados satisfatórios na estimativa de graus-dia. As metodologias tradicionais apresentaram desempenhos satisfatórios quanto à estimativa de grausdia com base na curva de temperatura horária para cada dia e para os agrupamentos de três, sete, 15 e 30 dias. Pelo método numérico de integração, a região de Botucatu, Estado de São Paulo, apresentou disponibilidade térmica anual média de 1.070,6 GD para a cultura da cana-de-açúcar.
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Cellulolytic enzymatic broth by Trichoderma reesei ATCC 2768 cultived in shaker using cashew apple bagasse and coconut shell bagasse, as substrate for fermentation, was used to investigate the enzymatic hydrolysis of these substrates after pre-treatment with 1 M NaOH, wet-oxidation as well as a combination of these treatments. Hydrolysis runs were carried at 125 rpm, 50ºC and initial pH of 4.8 for 108 hours. Enzymatic broth produced using cashew apple bagasse treated with 1M NaOH (1.337 UI/mL CMCase and 0.074 UI/mL FPase), showed after the hydrolysis an initial of 0.094 g of reducing sugar/g of substrate.h with 96% yield of total reducing sugars while for the coconut shell bagasse treated using the alkaline process (0.640 UI/mL CMCase and 0.070 UI/mL FPase) exhibited an initial hydrolysis velocity of 0.025 g of reducing sugar/g of substrate.h with 48% yield of total reducing sugars. For the treatment with wet-oxidation using cashew apple bagasse as substrate enzymatic broth (0.547 UI/mL CMCase) exhibited an initial hydrolysis velocity of 0.014 g of reducing sugars/g of substrate.h with a lower yield about 89% of total reducing sugars compared to the alkaline treatment. Enzymatic broth produced using coconut shell treated by wet-oxidation showed an initial hydrolysis velocity of 0.029 g of reducing sugar/g of substrate.h with 91% yield. However, when the combination of these two treatments were used it was obtained an enzymatic broth of 1.154 UI/mL CMCase and 0.107 FPase for the cashew apple bagasse as well as 0.538 UI/mL CMCase and 0,013 UI/mL de FPase for the coconut shell bagasse. After hydrolysis, initial velocity was 0.029 g of reducing sugar/g of substrate.h. with 94% yield for the cashew apple bagasse and 0.018 g de reducing sugar/g of substrate.h with 69% yield for coconut shell bagasse. Preliminary treatment improves residues digestibility showing good yields after hydrolysis. In this case, cellulose from the residue can be converted into glucose by cellulolytic enzymes that can be used for ethanol production
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)