934 resultados para Linear response


Relevância:

60.00% 60.00%

Publicador:

Resumo:

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

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Vitamin A is important to the proper development and functioning of the body, appearing in several metabolic functions. This experiment was conducted with aim evaluate to the vitamin A supplementation in diets for Goldfish Carassius auratus. The experimental was completely randomized with six treatments (0, 2.000, 4.000, 8.000, 16.000 and 32.000 IU of vitamin A kg(-1) diet) with four repetitions into 24 experimental cages, with capacity for 150 liters useful volume, made of mesh shading, installed inside a masonry circular tank with a capacity of 25 m(3) of water. 192 fish with an average initial weight of 6.66 +/- 0.57 g and initial length of 7.30 +/- 0.33 cm, feed at 8h, 11h, 14h and 17h at satiety were used. Evaluated the effects on productive performance and intensity of yellow-red coloring of the skin of the fish were. The Linear Response Plateau analysis of weight gain and length total, feed conversion and daily growth rate versus vitamin A requirement estimate showed 2,624, 2,385 and 2,358, 4,381 and 2,866 IU of vitamin A per kg diet, respectively. The data indicated that this vitamin has little or no influence on the intensity of the skin color of the Goldfish.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

A field trial was conducted designed in a completely randomized block in a 4 x 3 factorial arrangement to evaluate the application of nitrogen doses (N) (0, 40, 80 and 160 kg/ha) on the morphogenical characteristics and dry matter partition of three forage grasses (Panicum maximum cvs. Mombasa and Tanzania and Brachiaria sp. Hybrid Mulato). The leaf appearance (LAR, leaf/day) and stretching (LER; mm/day) rates, the number of green leaves per tiller (NLT) and the average weight of tillers (MTW; g) presented s positive linear response to the N dose while the phyllochron (Phil; day/leaves) showed a negative linear response. The highest LER, IAL and final leaf length (FLL; cm) occurred in the Mombaca and Tanzania grasses, while the highest LAR occurred in the Mulato grass. There was a negative quadratic effect of the N dose on the stem elongation rate (SER; mm/day) and LF. The Mombaca and Tanzania grasses presented the highest SER; however, in just two forages. The production of total dry matter (TDM; kg/ha), leaves (LDM; kg/ha) and stems (SDM; kg/ha) increased linearly and quadratically with the N dose, respectively, for the Mombaca and Tanzania grasses. There was a high positive correlation among DM, LDM and SDM and the Mombaca grass MTW. The dry matter production and morphogenic characteristics were influenced by the nitrogen fertilization as a result of the substantial increase in the flow of tissues stimulated by fertilization, proving the importance of N for forage biomass accumulation.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

A biomimetic sensor is proposed as a promising new analytical method for determination of norfloxacin (NF) in pharmaceuticals. The sensor was prepared by modifying a glassy carbon electrode surface with a Nafion® membrane doped with poly(copper phthalocyanine) complex [poly-CuPc]. Amperometric measurements carried out with the sensor under an applied potential of -0.05 V vs Ag|AgCl in 0.1 mol L-1 acetic acid containing 1.5 × 10-3 mol L-1 hydrogen peroxide showed a linear response range from 2.0 × 10-4 to 1.2 × 10-3 mol L-1. Selectivity and interference studies were also performed. A sensor response mechanism is proposed, based on the experimental evidence. Recovery studies were carried out using environmental samples, in order to evaluate the sensor’s potential for use with these sample classes. Finally, sensor performance was evaluated using analyses of commercial formulations.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Pós-graduação em Ciência dos Materiais - FEIS

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Pós-graduação em Engenharia Elétrica - FEIS

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Glucose biosensors based on lyophilised, crystalline and cross-linked glucose oxidase (GOx, CLEC(R)) and commercially available lyophilised GOx immobilised on top of glassy carbon electrodes modified with electrodeposited Prussian Blue are critically compared. Two procedures were carried out for preparing the biosensors: (1) deposition of one layer of adsorbed GOx dissolved in an aqueous solution followed by deposition of two layers of low molecular weight Nafion(R) dissolved in 90% ethanol, and (2) deposition of two layers of a mixture of GOx with Nafion dissolved in 90% ethanol. The performance of the biosensors was evaluated in terms of linear response range for hydrogen peroxide and glucose, detection limit, and susceptibility to some common interfering species (ascorbic acid, acetaminophen and uric acid). The operational stability of the biosensors was evaluated by applying a steady potential of -50 mV versus Ag/AgCl to the glucose biosensor and injecting standard solutions of hydrogen peroxide and glucose (50 muM and 1.0 mM, respectively, in phosphate buffer) for at least 5 h in a flow-injection system. Scanning electron microscopy was used for visualisation of the Prussian Blue redox catalyst and in the presence of the different GOx preparations on the electrode surface. (C) 2001 Elsevier B.V. B.V. All rights reserved.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

Estudou-se a melhor relação entre lisina digestível (LIS) e energia metabolizável (EM) e efeitos no desempenho e balanço de nitrogênio em leitões na fase de creche. No desempenho foram usados 216 leitões dos 6,90 ± 1,11 kg de peso inicial aos 12 kg, aproximadamente. No metabolismo eram 48 leitões com 9,31 ± 2,09 kg. As concentrações de LIS eram: 1,302; 1,390 e 1,497% e de EM: 3.510, 3.700 e 3.830 kcal/kg, combinadas em um arranjo fatorial 3 × 4 e distribuídas em delineamento de blocos ao acaso. No desempenho dos leitões houve interação LIS em no ganho de peso e conversão alimentar. No ganho de peso a resposta para LIS foi linear crescente nas dietas com 3.510 kcal e 3.830 kcal de EM. Na conversão alimentar observou-se efeito quadrático de LIS nas dietas que continham 3.510 kcal e efeito linear de LIS nas dietas com 3.830 kcal de EM. O efeito quadrático de LIS dentro de 3.510 kcal indicou 1,44% do aminoácido digestível como nível ótimo ou a ingestão de 4,16 g LIS/Mcal de em consumida. A resposta linear positiva na conversão alimentar ao acréscimo de LIS nas dietas com 3.830 kcal em indica maior eficiência dos leitões ao acréscimo do aminoácido quando o nível de energia é alto. No ensaio de metabolismo o aumento de em sugere maior retenção de N, enquanto o acréscimo de LIS sugere menor retenção do N ou na relação Mcal de EM:% LIS. A interação observada nos dois ensaios, todavia, indica que a relação LIS:EM, depende do nível energético e da característica considerada. A variação de LIS e em na dieta indica 4 g LIS/Mcal de em consumida, o que corresponde à ingestão diária aproximada de 7,8 g de LIS.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

The concentration of nutrients in plant is related to the soil, fertilization, climate, season, cultivar and cultural practices. Aiming to evaluate the soil chemical properties, the dry matter production of shoots and roots, nutrient content in the plant and the chemical composition of the grass Tierra Verde subjected to levels of organic biofertilizer as nitrogen source, an experiment was conducted in a greenhouse at the Faculty of Veterinary Medicine , UNESP, Araçatuba-SP, January-September 2010. Treatments were arranged in a completely randomized design with six fertilized biofertilizer doses (0, 33, 66, 132, 264, 528 m3 ha-1) and five repetitions for three cuts. We used the model split plot, with doses of biofertilizer considered as main treatments and cuts as sub-plots. We obtained a linear response in the production of dry mass of shoots and roots to the dose of 528 m3 ha-1 of organic biofertilizer. Nitrogen fertilization influenced the soil chemical properties and levels of organic matter, sulfur, boron and manganese, and in foliar levels of phosphorus, potassium and copper. The chemical composition was not altered by the influence of organic biofertilizer doses applied to the soil.

Relevância:

60.00% 60.00%

Publicador:

Resumo:

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

Relevância:

60.00% 60.00%

Publicador:

Resumo:

A bare graphite-polyurethane composite was evaluated in the tetracycline (TC) determination in natural water samples. Using differential pulse voltammetry (DPV), a linear response was observed in the range of 4.00-40.0 mu mol L-1 with limit of detection of 2.80 mu mol L-1, without the need of surface renewing between successive runs. During the tetracycline determination in water samples, recoveries between 92.6 and 100% were found. The results for TC determination in water samples after a pre-concentration stage agreed with spiked value at a 95% confidence level according to student t-test.