995 resultados para mineral supplement


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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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High soil acidity influences the availability of mineral nutrients and increases that of toxic aluminium (Al), which has a jeopardizing effect on plant growth. The objective of this research was to evaluate the effects of soil liming on the development of guava (Psidium guajava L.) plants, on soil chemical characteristics, and on fruit yield. The experiment was carried out at the Bebedouro Citrus Experimental Station, state of São Paulo, Brazil, in a Typic Hapludox soil, from August 1999 to March 2003. The treatments consisted of limestone dose: D0 = zero; D1 = half dose; D2 = total dose; D3 = 1.5 times the dose, and D4 = 2 times the dose to raise the V value to 70%. The doses corresponded to zero, 1.85, 3.71, 5.56, and 7.41tha(-1) applied to the upper soil layer (0-30cm deep) before planting. The results showed that liming caused an improvement in the evaluated soil chemical characteristics up to a depth of 60cm in soil samples both in the line and between lines. The highest fruit yields were obtained when the base saturation reached a value of 55% in the line and 62% between the lines. Foliar levels of calcium (Ca) and magnesium (Mg) were 8.8 and 2.5gkg-1, respectively. The highest limestone dose maintained the soil base saturation (at the layer of 0-20cm) in the line close to 55% during at least 40 months after the incorporation of limestone.

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O desenvolvimento das grandes cidades tem gerado um dos maiores desafios ambientais enfrentados na atualidade, que é a gestão eficaz de resíduos sólidos. A grande variedade e quantidade dos resíduos produzidos diariamente, tem tornado a destinação ecologicamente correta e sustentável destes materiais cada vez mais difícil. Dentre os vários resíduos produzidos diariamente destacam-se os lodos oriundos de estações de tratamento de esgotos, denominados de lodos de esgoto, cuja destinação final segura tem sido discutida mundialmente em diversos estudos, tendo em vista que a tendência de geração deste tipo de resíduo tende a crescer com o aumento do saneamento das cidades. Uma forma amplamente difundida nos países desenvolvidos para destinação dos lodos de esgoto é a incineração destes materiais para posterior envio das cinzas geradas neste processo a aterros sanitários. Porém, tem-se estudado formas alternativas de disposição, destacando-se a utilização destas cinzas como adição mineral em concretos e argamassas de cimento Portland. Sabe-se que o desempenho de resíduos de incineração como adição mineral em matrizes cimentícias, depende em grande parte da capacidade de atuação destes materiais como elementos pozolânicos ou como fileres, podendo estas características serem influenciadas pela temperatura de queima ao qual estes resíduos foram submetidos. Neste sentido, verificou-se com esta pesquisa a influência da temperatura empregada na queima dos lodos sépticos no índice de atividade pozolânica (IAP) das cinzas geradas como resíduo deste processo, aqui denominadas de cinzas de lodo séptico (CLS), sendo em seguida, avaliadas as implicações técnicas e microestruturais da utilização deste resíduo em teores de 10%, 20% e 30% como adição mineral em concretos de cimento Portland. Os resultados obtidos demonstraram não haver alterações significativas no IAP das CLS em decorrência da temperatura utilizada durante o processo de queima dos lodos de esgoto. Além disso, verificou-se que embora a utilização das CLS tenham provocado diminuição da trabalhabilidade dos concretos para todos os teores de incorporação, estas melhoraram a resistência mecânica à compressão, o índice de vazios, a absorção de água e o comportamento microestrutural dos concretos contendo 10% e 20% de resíduo

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The objective of the present study was to evaluate the characteristics of the sward canopy of Marandu grass during the rainy season, the wet-to-dry transition and the dry seasons, between March and September 2004, under intermittent grazing, and to correlate those characteristics with the performance of crossbred heifers receiving mineral supplements ad libitum or protein supplements. The experiment consisted of a randomized block design with three blocks (set of 13 paddocks), each containing five crossbred heifers per experimental unit, totaling 15 replicates. The heifers were given protein supplements daily in individual stalls and received an average 4 g/kg/day of the supplement during the rainy season and 5 g/kg/day during the dry season. Their weight gain was assessed monthly. The pasture structure was assessed through destructive sampling, and the bromatological composition of esophageal extrusa samples was also assessed. Analysis of variance was used to assess performance, and regression analysis was used to evaluate the sward canopy characteristics in relation to the months of the year. A cluster procedure was used to determine the similarity between the months of the year under assessment. Two different groups were formed for pasture evaluation: one group including the months of March to July and another group including the months of August and September. The first group exhibited a better canopy structure than the second group. This fact was corroborated by the animal performance, which was lower during the months of the second group. Low-intake protein supplementation was effective in increasing the performance of the grazing heifers. Pasture structure is critical for animal performance in a grazing environment, regardless of the type of supplementation.

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The objective of this study was to assess the sward canopy structure of Brachiaria brizantha cv. Marandu pastures maintained in three grazing intensities under continuous stocking system during the rainy season, along with the behavior and performance of grazing beef heifers supplemented with mineral salt or an energy/protein supplement. Three levels of forage allowance were assessed: 2.0, 2.5 and 3.0 kg of forage/kg of live weight, combined with two supplements (ad libitum mineral salt, and an energy/protein supplement at 0.3% of live weight/day, supplied daily). The experiment was designed as a randomized block study with two replications. The supplements did not influence the variables related to the canopy structure. Canopy height was greater at higher forage allowances during the late summer and early fall. Similarly, the stem mass was greater in pastures with higher forage allowances. Animals fed protein supplement spent less time grazing than animals supplemented with mineral salt. Stocking rate was higher in pastures with lower forage allowance levels, which increased the live weight gain per grazing area. Daily weight gain did not vary according to the forage allowance levels. The use of an energy/protein supplement did not affect the stocking rate; however, it increased individual live weight gain and live weight gain per grazing area compared with mineral salt supplementation. The use of energy/protein supplements is an efficient alternative to enhance animal performance and production under grazing systems during the rainy season

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The objective of this study was to evaluate the Brachiaria brizantha cv. Marandu canopy structure maintained at different grazing heights under a continuous stocking rate and with a dietary supplementation strategy for the animals during the rainy season. This study also intended to observe the relationships of these variables with the grazing behaviors of the heifers. The effects of three canopy heights (15, 25 and 35 cm) were evaluated in association with three types of supplements: one mineral and two protein/energy supplements, the first with a high rumen degradable protein and energy and the others with a low ratio. Both the protein/energy supplements were provided at 0.3% of body weight/day. The experimental design was completely randomized, with two replications and repeated measures, and took place during the period from January to April 2008. The supplementation strategies did not affect any variable related to the canopy structure. Total and green herbage masses and the ratio of green/dead material increased with canopy height. The leaf/stem ratio was higher in the lowest canopy height: 15 cm. Changes in the canopy structure caused variations in the grazing behavior of the animals. Animals maintained in the 15-cm-tall pasture grazed for a longer time, increasing the time for each meal, but the number of meals was lower than that of the animals grazing within the 35-cm-tall pasture. The grazing time of animals receiving the energy/protein supplement was lower only in the period of the day during which it was supplied. Canopy structure is affected by sward height, and changes animal behavior. Supplementation does not affect the canopy structure of the pastures with similar heights.

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It s more and more evident the subject of the shortage of water, worsened by the accelerated urbanization, growth of the population, increase of the demand and of the costs of its treatment, factors that are also tied up to the increase of the consumption of mineral waters, whose chemical composition or physical-chemistries characteristics do with that are considered beneficial to the health. The growth accelerated all over the world in its consumption aims the concern with the waters quality, the health and the incentive to the consumption of natural products. However, in spite of quite valuable, that resource is explored, most of the time, without optimization of production or actions that avoid wastefulness. This research is justified for the need of minimizing the negative environmental impacts caused by the mineral water s production, mainly in what it say about the generation of effluents and wastes in the productive process, through the study, development and application of cleaner production tools for the environmental management, pertinent for that section. The applicability of Environmental Management System was determined by means of the characterization of the environmental aspects of productive process in a company of the section, in the state of Rio Grande do Norte and of the discussion of the panoramas that demonstrate the tendency for a sustainable development. Actions as a reforestation, optimization of energy and water uses, recycle of solid residues and water reuse were applied during the research, resulting in the considerable reduction of wastes of raw materials and inputs and consequent environmental and economic won. A specific methodology was proposed with concepts of Environmental Management, integrating with Quality Management. As foundations for the elaboration of the methodology, it was realized a similarity analysis among the systems and, mainly, an analysis of the experiences observed in the case study, including specificities, needs and difficulties of the company. With these results, the implantation of a EMS as a company strategy has environmental, economic and social benefits, and this research can be applied and adequate to others companies and sectors

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The strengthening of the domestic industry in Brazil required the modernization, mechanization and expansion of salt production. Thereafter the production of sea salt started to be made in a process of continuous flow, where the product is constantly stored in yards, with daily movements in and out of salt. Thus far, the major bottleneck found in this production process is the control of production, because due to the large amount produced and variety of losses existing in the various stages of production there are not a regulated and safe way to control inventories with accuracy and speed demanded. In a typical case with a salt marsh company of Rio Grande do Norte state, salt produced is stored in two open courtyards and inventory control of salt made by carrying input / output relationship of salt in each storage yard. This work developed a conceptual model of inventory control, based on topography, adopting surveys into one of the courtyards of the company. There were 25 biweekly survey measurements over a year book to generate digital models representing the stock. For each measurement, results were compared with the values of inventory accounting provided by the salt marsh in order to identify existing losses and mark out the sales department on the actual stock available at each measurement date. Inventories calculated by the model indicated losses of 6,349 tonnes for the period of one year book and 3,279 tonnes for the period between harvests, when compared to the accounting control

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The objective of this study was to evaluate performance and daytime ingestive behavior of 84 Nellore young bulls in the post-weaning phase kept on Brachiaria brizantha cv. Marandu pastures during the dry season. Treatments were protein mineral supplementation (1 g/kg body weight) and protein+energy mineral supplementation (3 g/kg body weight). The experimental area comprised 12 paddocks in a total area of 27.36 ha, divided in two blocks of six paddocks each, having three replications per treatment in each block, with 42 animals/treatment. The data were subjected to variance analysis with repeated measures over time via procedure PROCMIXED of SAS (Statistical Analysis System, version 9.0) and means were compared by the Tukey test at 5% probability. The initial average weight of animals was 204.8 kg; final weights were 260.9 and 276.9 kg for animals that received protein and protein+energy supplement, respectively. The forage availability, sward height and stocking rate values did not differ with supplementation, but they showed difference between the experimental periods. The average time spent grazing during daylight of animals fed protein+energy supplement was shorter as compared with those which consumed protein supplement. Animals kept under the same pasture conditions during the dry season show better performance when they receive protein+energy supplement than protein supplement.

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An experiment was carried out with male and females broilers of two different commercial breeds to evaluate bone mineral density of the right femur head. A number of 600 one-day-old broilers were raised in an experimental poultry house up to 42 days of age at the School of Veterinary Medicine and Animal Science of UNESP, Botucatu, Brazil. After slaughter, three males and three females in each breed in each of the established gross scores were selected. Their femora heads were submitted to gross examination, and subsequently the thighs were submitted to the Veterinary Hospital for radiographic analysis. Femora were also submitted to bone resistance, Seedor index, and dry matter content analyses. All these bone quality characteristics were different between males and females, independent of breed. Breeds presented similar behavior. It was possible to establish correlations between bone quality parameters, and confidence intervals for bone mineral density values, correlating them to femoral degeneration score, which allows characterizing femoral head lesions by radiographic optical densitometry.

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Este trabalho teve como objetivo avaliar os efeitos das lâminas brutas de irrigação na concentração de nutrientes de mudas de Eucalyptus grandis, produzidas em diferentes substratos. O experimento foi realizado na Camará - Mudas Florestais, em Ibaté, SP, e constituiu-se de um fatorial 5 x 4, sendo cinco lâminas brutas de irrigação diárias (6, 8, 10, 12 e 14 mm), aplicadas em diferentes horários (10, 13 e 16 h), e quatro substratos (FB - fibra de coco; CPV - casca de pinus e vermiculita; CATV - casca de pinus, carvão, turfa e vermiculita; e um MIX - 70 % de CPV e 30 % de FB). Foram determinadas os conteúdos dos nutrientes na parte aérea e no sistema radicular das mudas. Os resultados indicaram que houve influência das lâminas de irrigação e dos substratos no conteúdo dos nutrientes das mudas com maior acúmulo dos mesmos à medida que o fornecimento de água foi maior. As plantas crescidas nos substratos FB e CPV registraram os maiores acúmulos de nutrientes. CPV foi o melhor em se tratando do acúmulo dos macronutrientes nas raízes e também, juntamente com FB, o melhor para o acúmulo dos micronutrientes nas raízes e na parte aérea. Não houve influência dos substratos no acúmulo dos macronutrientes na parte aérea, porém houve das lâminas de irrigação.

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Com o objetivo de estudar o efeito da calagem e de diferentes quantidades de calcário na cova de plantio sobre o desenvolvimento inicial do mamoeiro e a concentração de nutrientes nas folhas, desenvolveu-se o presente trabalho na Estação Experimental Presidente Médici, município de Botucatu, SP. Dentre os resultados obtidos constatou-se que: (a) A calagem com calcário dolomítico favoreceu o desenvolvimento inicial do mamoeiro; (b) A adição de calcário dolomítico na cova de plantio não teve nenhum efeito sobre o desenvolvimento inicial do mamoeiro; (c) A calagem realizada durante o preparo do solo para o plantio teve maior influência nas variações das concentrações dos nutrientes nas folhas do mamoeiro do que a adição de calcário na cova por ocasião da adubação fundamental; (d) Na competição iônica dos nutrientes catiónicos Ca e Mg, o Mg foi mais efetivo.

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Para recomendações de adubação mais racionais, é fundamental o conhecimento das exigências nutricionais da cultura do arroz, nos diversos sistemas de cultivo. Objetivando estudar a influência de lâminas de água na nutrição e exportação de nutrientes pelo arroz de terras altas, cultivar IAC 201, sob dois níveis de adubação, foram instalados experimentos em um Latossolo Vermelho distrófico, em Selvíria (MS), nos anos agrícolas de 1994/95 e 1995/96. O delineamento foi de blocos casualizados, com quatro repetições. Os tratamentos constituíram-se da precipitação natural e de quatro lâminas de água fornecidas por aspersão. A lâmina L2 foi baseada no coeficiente de cultura (Kc) do arroz de terras altas. As lâminas L1 e L3 foram definidas como 0,5 e 1,5 vez os Kcs utilizados em L2, respectivamente, e na lâmina L4 foi adotado Kc = 1,95 durante todo o ciclo da cultura. em 1995/96, foram utilizados os mesmos tratamentos em parcelas subdivididas, sendo as subparcelas constituídas por duas doses de adubação (AD1 - 12 kg ha-1 de N, 90 de P2O5 e 30 de K2O, e AD2 - 24 kg ha-1 de N, 180 de P2O5 e 60 de K2O). A menor disponibilidade de água durante a fase vegetativa e reprodutiva proporcionou redução na produção de matéria seca, nos teores e quantidades de nutrientes acumuladas na parte aérea. O sistema irrigado por aspersão, independentemente da lâmina utilizada, proporcionou maior produtividade de grãos e exportação de nutrientes. em solos com teores adequados de nutrientes para o sistema de sequeiro, não há resposta ao aumento da adubação mineral pelo arroz no sistema irrigado por aspersão, apesar da maior extração de nutrientes.

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

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Cyclic oligomers were identified in PET bottles used for mineral water and fruit juice using MS and H-1 and C-13 NMR: a first series cyclic trimer, a first series cyclic tetramer, a first series cyclic dimmer and a second series cyclic trimer. An analytical method to determine first series cyclic trimer in these bottles was developed and validated, using HPLC. The first series cyclic trimer levels were 316-462 mg/100 g of PET bottle. (c) 2005 Elsevier B.V. All rights reserved.