349 resultados para solução saturada de NaCl
Resumo:
α2-Adrenoceptor activation with moxonidine (α2-adrenergic/imidazoline receptor agonist) into the lateral parabrachial nucleus (LPBN) enhances angiotensin II/hypovolaemia-induced sodium intake and drives cell dehydrated rats to ingest hypertonic sodium solution besides water. Angiotensin II and osmotic signals are suggested to stimulate meal-induced water intake. Therefore, in the present study we investigated the effects of bilateral injections of moxonidine into the LPBN on food deprivation-induced food intake and on meal-associated water and 0.3 M NaCl intake. Male Holtzman rats with cannulas implanted bilaterally into the LPBN were submitted to 14 or 24 h of food deprivation with water and 0.3 M NaCl available (n = 6-14). Bilateral injections of moxonidine (0.5 nmol/0.2 μl) into the LPBN increased meal-associated 0.3 M NaCl intake (11.4 ± 3.0 ml/120 min versus vehicle: 2.2 ± 0.9 ml/120 min), without changing food intake (11.1 ± 1.2 g/120 min versus vehicle: 11.2 ± 0.9 g/120 min) or water intake (10.2 ± 1.5 ml/120 min versus vehicle: 10.4 ± 1.2 ml/120 min) by 24 h food deprived rats. When no food was available during the test, moxonidine (0.5 nmol) into the LPBN of 24 h food-deprived rats produced no change in 0.3 M NaCl intake (1.0 ± 0.6 ml/120 min versus vehicle: 1.8 ± 1.1 ml/120 min), nor in water intake (0.2 ± 0.1 ml/120 min versus vehicle: 0.6 ± 0.3 ml/120 min). The results suggest that signals generated during a meal, like dehydration, for example, not hunger, induce hypertonic NaCl intake when moxonidine is acting in the LPBN. Thus, activation of LPBN inhibitory mechanisms seems necessary to restrain sodium intake during a meal. © 2007 Elsevier B.V. All rights reserved.
Resumo:
During eight weeks, in summer, four endurance trained high performance horses were worked in resistence exercise, recieving two different types of hydratatio, water or an isotonic solution containing carbohydrates, with the objective to compare their performance physiological parameters. Only the RT (rectal temperature), HR (heart rate), RR (respiratory rate), weight, total protein, glucose, the electrolytes K, Ca and the muscular enzyme CK presented distance effect. The others parameters evaluated, there weren't any identified effects of treatment and of the interaction between distance and treatments, with a significancy level of 5%, and it was concluded that the isotonic solution containing carbohydrate didn't have any significant influence on the animal's performance when compared to water.
Resumo:
The objective of this work was to evaluate the effect of omission of macronutrients in the growth and the nutritional state of elephant-grass plants (Pennisetum purpureum Shum cv. Mott). The experiment was developed in the FCAV/UNESP, in Jaboticabal-SP,Brazil, using nutrient solution. The experimental design was completely randomized blocks, with seven treatments (the complete solution proposed by Hoagland & Amon (1950) and the individual omission of N, P, K, Ca, Mg and S, in these solution), in three repetitions. Pre-germinated plants were placed in pot (5 dm3), containing the nutrient solution, which was aerated constantly during the experimental period and the respective treatments, with three replications each. Weekly, the height of the plants, the leaf number, apex diameter and number of tillers were evaluated as well as plant nutritional state. The omission of N, P, K, Ca, Mg and S limited the production of dry weight of shoot the elephant grass, compared to the full treatment. The deficiency of a macronutrient, in addition to promoting reduction of its content in the shoot, resulted in reducing the accumulation of most macronutrients, with resultant morphological changes, translated as characteristic symptoms of deficiency.
Resumo:
Soybean is a crop of great importance for Brazil, and knowledge of their nutritional status allows production and high quality products. Thus, the present work aimed to evaluate the culture of the soybean cv. BRSMG 68 (Vencedora), submitted to macronutrients omission on the development, nutritional status and the visual symptomatology of nutrient deficiency. The design used was completely randomized, with seven treatments that corresponded to the complete (macro and micronutrients) solution and the individual omission of N, P, K, Ca, Mg and S. The treatments were applied two weeks after the emergency of the soybean. The nutrient solution was constantly oxygenated and replaced weekly, and the pH monitored daily remained around 5. After six weeks of application of the treatments, the height of the plants, number of leaves, stem diameter was evaluated, matter dry accumulated in the roots, it leaves aerial and the nutritional state and the characterization of the visual symptoms. The macronutrient deficiency promoted a decrease in production of root and shoot dry mass of soybean cultivar BRSMG 68 (Vencedora) in nutrient solution, for the full treatment. The most limiting nutrient for dry matter production of soybean compared to complete treatment were N, S and K, with decreases of 90, 76 and 73%, respectively. Individual omissions resulted in morphological changes, which were translated by characteristic visual symptoms of nutritional deficiency of the respective nutrient.
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
The study of growth and uptake of nutrients is important to determine the times of increased demand in order to schedule the fertigation. The present research was developed with the objective of evaluating the effects of different levels of electrical conductivity on growth and accumulation of nutrients in chrysanthemum plants under greenhouse conditions. The electrical conductivity levels on the applied solution were 1.42, 1.65, 1.89, 2.13 and 2.36 dS m-1 (bud vegetative stage); 1.71, 1.97, 2.28, 2.57 and 2.85 dS m-1 (bud stage). The dry mass of the aerial portion of the plant and the contents of macronutrients and micronutrients were determined every 14 days. The nutrient accumulation in chrysanthemum plant showed similar trend as compared to dry matter accumulation. The nutrients presented the following order of absorption: K>N>Ca>Mg>P>S (1425, 892, 184, 150, 110 and 59 mg plant-1) and Fe>Zn>B>Mn>Cu (2254, 2219, 1725, 1287, 210 μg plant-1). The content of most nutrients increased with increase in electrical conductivity of the solution, without salt effect up to EC of 2.85 dS m-1.
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
The objective of this research was obtain collagen biomembranes treated in alkaline solution for 72 hours (GE) from tendineous diaphragmatic center of equines and compare its biocompatibility with membranes preserved in a glycerin solution 98% (GG) and membranes do not treated (GC). The membranes were implanted in the internal fascia of recto abdominis muscle of equines and removed, with adjacent tissues, seven, 63 and 126 days postoperative for the preparation of histological slides. The histomorphometric study revealed more intense inflammatory process to GG and CC implants and faster healing for GE implants. It was concluded that the collagen biomembranes treated in alkaline solution is more biocompatible than biomembranes preserved in 98% glycerin.
Resumo:
Adsorption of Reactive Blue 19 dye onto activated red mud was investigated. Red mud was treated with hydrogen peroxide (LVQ) and heated at both 400 °C (LVQ400) and 500 °C (LVQ500). These samples were characterized by pH, specific surface area, point of zero charge and mineralogical composition. Adsorption was found to be significantly dependent on solution pH, with acidic conditions proving to be the most favorable. The adsorption followed pseudo-second-order kinetics. The Langmuir isotherm was the most appropriate to describe the phenomenon of dye removal using LVQ, LVQ400 and LVQ500, with maximum adsorption capacity of 384.62, 357.14 and 454.54 mg g-1, respectively.
Resumo:
The corrosion behaviour of metal matrix composites (MMCs) is strictly linked with the presence of heterogeneities such as reinforcement phase, microcrevices, porosity, secondary phase precipitates, and interaction products. Most of the literature related to corrosion behaviour of aluminium matrix composites (AMCs) is focused on SiC reinforced AMCs. On the other hand, there is very limited information available in the literature related to the tribocorrosion behaviour of AMCs. Therefore, the present work aims to investigate corrosion and tribocorrosion behaviour of Al-Si-Cu-Mg alloy matrix composites reinforced with B4C particulates. Corrosion behaviour of 15 and 19% (vol) B4C reinforced Al-Si-Cu-Mg matrix composites and the base alloy was investigated in 0.05M NaCl solution by performing immersion tests and potentiodynamic polarisation tests. Tribocorrosion behaviour of Al-Si-Cu-Mg alloy and its composites were also investigated in 0.05M NaCl solution. The tests were carried out against alumina ball using a reciprocating ball-on-plate tribometer. Electrochemical measurements were performed before, during, and after the sliding tests together with the recording of the tangential force. Results suggest that particle addition did not affect significantly the tendency of corrosion of Al-Si-Cu-Mg alloy without mechanical interactions. During the tribocorrosion tests, the counter material was found to slide mainly on the B4C particles, which protected the matrix alloy from severe wear damage. Furthermore, the wear debris were accumulated on the worn surfaces and entrapped between the reinforcing particles. Therefore, the tendency of corrosion and the corrosion rate decreased in Al-Si-Cu-Mg matrix B4C reinforced composites during the sliding in 0.05M NaCl solution. © 2013 Elsevier B.V.
Resumo:
Pós-graduação em Matemática - IBILCE
Resumo:
Pós-graduação em Cirurgia Veterinária - FCAV
Resumo:
Pós-graduação em Ciências Cartográficas - FCT
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Resumo:
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)