Utilização da mínima quantidade de lubrificante (MQL) com água no processo de retificação cilíndrica em cerâmica avançada com rebolo de ligante resino cerâmico/metálico

Pós-graduação em Engenharia Mecânica - FEB

Produção e imobilização de celulases em matriz de agarose com diferentes ativações químicas

Pós-graduação em Biotecnologia - IQ

Avaliação nutricional de silagem de restos culturais de abacaxi pérola

Pós-graduação em Zootecnia - FCAV

Thermo-sensitive chitosan-cellulose derivative hydrogels: swelling behaviour and morphologic studies

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Effects of litter manipulation in a tropical Eucalyptus plantation on leaching of mineral nutrients, dissolved organic nitrogen and dissolved organic carbon

Although many studies have shown that soil solution chemistry can be a reliable indicator of biogeochemical cycling in forest ecosystems, the effects of litter manipulations on the fluxes of dissolved elements in gravitational soil solutions have rarely been investigated. We estimated the fluxes of NH4-N, NO3-N, K, Ca, Mg, Na, Cl, dissolved organic nitrogen (DON) and dissolved organic carbon (DOC) over the first two years after re-planting Eucalyptus trees in the coastal area of Congo. Two treatments were replicated in two blocks after clear-cutting 7-year-old stands: in treatment R, all the litter above the mineral soil was removed before planting, and in a double slash (DS) treatment, the amount of harvest residues was doubled. The soil solutions were sampled down to a depth of 4 m and the water fluxes were estimated using the Hydrus 1D model parameterized from soil moisture measurements in 4 plots. Isotopic and spectroscopic analytical techniques were used to assess the changes in dissolved organic matter (DOM) properties throughout the transfer in the soil. The first year after planting, the fluxes of NH4-N, K, Ca, Mg, Na, Cl and DOC in the topsoil of the DS treatment were 2-5 times higher than in R, which showed that litter was a major source of dissolved nutrients. Nutrient fluxes in gravitational solutions decreased sharply in the second year after planting, irrespective of the soil depth, as a result of intense nutrient uptake by Eucalyptus trees. Losses of dissolved nutrients were noticeably low in these Eucalyptus plantations despite a low cation exchange capacity, a coarse soil texture and large amounts of harvest residues left on-site at the clear cut in the DS treatment. All together, these results clarified the strong effect of litter manipulation observed on eucalypt growth in Congolese sandy soils. DOM fluxes, as well as changes in delta C-13, C:N and aromaticity of DOM throughout the soil profile showed that the organic compounds produced in the litter layer were mainly consumed by microorganisms or retained in the topsoil. Below a depth of 15 cm, most of the DOC and the DON originated from the first 2 cm of the soil and the exchanges between soil solutions and soil organic matter were low. (C) 2014 Elsevier B.V. All rights reserved.

Comparison of polymers and ceramics in new and discarded electrical insulators: reuse and recycling possibilities

The expansion and maintenance of electricity distribution networks generates large amounts of waste, much of it in the form of discarded insulators that are not reused or recycled. This paper describes the results of tests on used and new ceramic and polymeric insulators to verify if their exposure to weathering justifies their replacement. In new and used ceramic insulators, properties such as contact angle, relative density, porosimetry, dilatometry and X-ray diffraction patterns showed no differences or the differences that were found could not be related to their use. The discarded ceramic material showed high thermal stability, an interesting characteristic for application as chamotte. It can also be reused to replace gravel used in substations. In polymeric insulators, thermogravimetry, differential scanning calorimetry and relative density test results suggest degradation of used material compared to new. This would justify their replacement and discard as waste, but they show little recycling potential.

RESPONSE OF CORN GROWN IN TILLAGE SYSTEM FOR THE APPLICATION OF NITROGEN DOSES IN A SEQUENCE OF PLANT COVER

The use of cover crops can produce large amounts of biomass, improving the cycling of nutrients, particularly nitrogen, promoting productivity gains and cost savings. Given this, the objective was to evaluate the use of N rates associated to cover crops grown in pre-harvest nutritional status, nitrogen accumulation and corn yield in both years. The experiment was conducted in an Oxisol with maize, no-tillage system. The experimental design was a randomized block, split plot with four replications. The main treatments were: six cropping systems (sun hemp, jack bean, lablab, millet, and velvet bean fallow) in secondary treatments: four doses of nitrogen (0, 60, 120 and 180 kg ha(-1) N). Corn yield was not affected by the type of coverage for pre-season, regardless of the nitrogen applied in the soil. Still, the use of nitrogen fertilizer in the soil promotes gains in grain yield in the first year of cultivation, regardless of the type of coverage in pre-season. In the first year (2006/2007) the species of coverage produced more biomass were velvet bean, jack bean, sun hemp and lablab, while in the second year (2007/08) were the sun hemp, millet, lablab, jack bean and velvet bean, respectively.

Aproveitamento de resíduos de laminação da madeira para a produção de painel estrutural

Products derived from wood or engineered products are becoming interesting alternatives to the replacement of solid wood in various applications, from structural components to the furniture industry and packaging. Among these products, there are panels built by strands, particles and fibers, each one having their particular characteristics and potential of use. Since the different types of panels are produced, waste generation is part of the process, and that more technological it is, it still generates losses of raw materials. Based on the need for rational use of raw materials and using almost full of industrially processed wood, It arises the proposal of this work, which seeks to use waste from the lamination, like pieces of strands, broken strands, strands rough, cracked strands to produce panels with structural characteristics of the OSL panel (Oriented Strand Lumber), LSL (Laminated Strand Lumber) and OSB (Oriented Strand Lumber). Besides the use of waste, this paper seeks an alternative to the use of the adhesive, because the industry uses formaldehyde-based adhesives, which over the press, they emit large amounts of formaldehyde, which is very aggressive to humans and environment. The panels made with polyurethane resin based on castor oil and hot-pressed were characterized by physical and mechanical tests according to specifications of European Standard (EN). High values of tensile strength, elastic modulus and density were found in the results of tests. Adding to stable values of swelling and moisture content, the panel studied adds attractive features to the panel market, especially in the civil construction

Avaliação do potencial genotóxico e mutagênico do efluente de uma refinaria de petróleo e dos rios sob sua influência, por meio de bioensaios com Oreochromis niloticus (Perciformes, Cichlidae)

The petrochemical industry represents a sector of intense activity, in constant expansion and great economic importance for Brazil. In order to be used in various human activities petroleum needs to suffer a refinement process that, besides requiring large amounts of water, produces large amounts of wastes, which are discharged in hydric resources. Petroleum is a complex mixture mainly comprised by hydrocarbons, many of them are recognized as toxic chemicals, which are able to induce a considerable environmental pollution. Since water is an important resource for the maintenance of ecosystems and is also the final receiver of effluent discharges of the petroleum industry, there is an imminent need to monitor, constantly, the hydric resources that are influenced by this industrial activity, so that it can be ensured the environmental health. This study aimed, mainly, to analyze the quality of water samples derived from refinement process performed of the largest petroleum refinery in Brazil (REPLAN), in distinct steps of the industry treatment, and waters of rivers associated to its activity. Micronuclei and Nuclear Abnormalities tests were performed in erythrocytes of the fish species Oreochromis niloticus exposed to water samples derived from refinery use and to rivers under the influence of their effluents, in order to evaluate its possible toxic, genotoxic and mutagenic effects. The results obtained show that the treatment carried out by the refinery, during the evaluated periods, was effective, since the substances present in the water samples did not induce significant genotoxic and/or mutagenic alterations in the genetic material of the test organisms. On the other hand, when the substances present in the refinery effluent mix with the ones derived from other industrial activities developed upstream of this industry, the resultant compound, in some periods, presented genotoxic potencial, characterized by a rise of erythrocytic...

Efeitos da exposição à sílica sobre a responsividade vascular e de vias aéreas de ratos

Silicosis, a common type of pneumoconiosis, is an occupational lung disease caused by inhalation of silica dust often with mining activity and thus reaches the miners. The fine and ultrafine silica particles deposited in the alveolar epithelium may lead to the development of progressive massive fibrosis. An increased reactive oxygen species (ROS) production has been proposed to explain the mechanism for induction of pulmonary fibrosis in silicosis. In this situation, alveolar macrophages are activated to phagocytes silica particles deposited in the alveoli. The activated macrophages secrete large amounts of ROS that in turn induce synthesis of fibrotic factors. In addition, the activity of antioxidant enzymes is impaired, which results in increased lipid peroxidation, as well as generating a local inflammatory process. Diffuse pulmonary fibrosis progresses with interstitial collagen deposition. Interstitial collagen overlies small pulmonary arteries and arterioles and thus it is associated with pulmonary hypertension in pulmonary fibrotic diseases. In addition, cytokines and silica particles passing through the respiratory membrane can reach the bloodstream. In this context, the increase in the generation of ROS in the circulation may lead to a reduction in the bioavailability of nitric oxide, an important endothelium-derived relaxing factor. A deficiency in the nitric oxide bioavailability can result in vascular endothelial dysfunction. Moreover, pro-inflammatory cytokines could contribute to the impairment of endothelial function. In the airways, pro-inflammatory cytokines can reduce the smooth muscle responsiveness to β- adrenergic agonists as isoproterenol. Thus, the aim of this study was to evaluate the effect of silica dust instillation in the function of the pulmonary artery, aorta and trachea of rats with acute silicosis. For this purpose, male Wistar rats were anesthetized... (Complete abstract click electronic access below)

Dinâmica da secreção de néctar em Zeyheria montana Mart. (Bignoniaceae) relacionada à atividade dos beija-fores polinizadores

The Cerrado is home to important biodiversity areas in the state of Sao Paulo. Therefore, research on the reproduction of species of this biome are essential to help conservation programs. Pollination is the main mechanism by which outcrossing plants perpetuate their populations, and the attractive, such as nectar, are of vital importance to many anthophilous animals and essential to the maintenance of interactions with pollinators. In this context, the objective of this study was to investigate the ecological dynamics of secretion and sugar composition of floral nectar in Zeyheria montana, an ornithophilous exclusive Cerrado species, visited preferentially by Colibri serrirostris, also exclusive to this biome. This dynamic was assessed in isolated flowers in pre-anthesis, using microsyringes to collect nectar and manual refractometer to measure the concentration. Experiments were carried out to evaluate production throughout anthesis, including the assessment of total daily production, the effect of successive removal, the rate of production during the day and night and changes in concentration and composition of sugars, which was performed in HPLC (High Performance Liquid Chromatography). The rate of nectar production was about three times greater at night with a concentration two times lower, resulting in a supply of large amounts of dilute nectar in the early morning hours, peak of visitation for hummingbirds. Moreover, the production of nectar was more pronounced before the anthesis, and is available to visitors already in newly opened flowers, which are preferentially visited by C. serrirostris. There was an increase in the nectar production of flowers in the group with successive manual removal upon the control group, suggesting that the withdrawal by visitors stimulates the production, ensuring the availability of the resource including flowers previously visited... (Complete abstract click electronic access below)

Aspectos gerais da síndrome anorexia caquexia do câncer em pequenos animais

The cancer anorexia-cachexia syndrome is the most common paraneoplastic syndrome in Veterinary Medicine. It is characterized by severe loss of muscle mass and adipose tissue resulting in severe unintentional weight loss, anemia, fatigue, negative nitrogen balance, immune dysfuntion and other metabolic disturbances. The SAC is not only a result of inadequate intake of nutrients. The tumor requires large amounts of nutrients to allow growth and causes changes in pacient metabolism to get this energy. Recent studies suggest that the metabolic changes by cancer can be measured by hormones and cytokines produced or by the patient or the tumor, but this not completely understood. Animals with SAC have lower survival time, the greater chance of complications during treatment and lower quality of life. With the increase in the number of cancer cases in domestic animals and longer lifespan after diagnosis of malignant disease through the use of antineoplastics drugs, diagnosis and treatment of cancer anorexia-cachexia syndrome has shown great importance in that patients may have higher survival then better quality of life. This paper aims to provide information about this complex and multifunctional syndrome and its possible treatments

Toxicidade de petróleo bruto sobre microcrustáceo Daphnia similis em água de rio e água de produção de petróleo

Aquatic ecosystems are suffering many impacts caused by human activities resulting from the activities occurring around them. With technological progress observed in recent years, this environment has received large amounts of chemicals from industries, agriculture and urban area that affect the aquatic biota. Among these sources of contamination, the oil industry has contributed to the pollution of aquatic environments with both effluents as produced water well as oil spills and their derivatives having toxicity to various organisms. With all the environmental issues has increased concern about water quality and has been used ecotoxicological tests with aquatic organisms to ecosystems to assess the toxicity of chemicals present in the water. In this context the microcrustacea Daphnia similis stands out as a freshwater organism very representative of the aquatic fauna of rivers and high sensitivity to environmental impacts. Thus, the present study aimed to evaluate the lethal toxicity of crude oil and produced water on this microcrustacea. The results showed that the microcrustacea presented high sensitivity to contaminants primarily crude oil. There was also the influence of environmental variables pH and temperature on the survival of organisms

Introdução de Lentinulaedodes (Shiitake) e Pleurotusostreatus (Shimeji) em bagaço de cana termo explodido para diminuição da toxicidade

Ethanol production has gained great prominence in the investment new renewable energy sources and Brazil is among the leaders of production. However, this activity generates large amounts of waste being the largest volume of the sugar cane bagasse. For this reason looking up ways to use this material as burning for energy production and composition of forage in the diet of ruminants, however there are difficulties to use this production for this last one. This paper proposes a microbiological treatment with Lentinula edodes and Pleurotus ostreatus in order to enable the bagasse in ruminant feed composition in order to be used more noble than their burning. After treatment with the fungus, tests were performed for quantifying crude protein by the method of Kjeldhal. It was verified that the protein content in the pure bagasse was 1.0% after fermentation the protein content was 4.2% with L.edodes and 4.9% with P. ostreatus. To evaluate the protein quality of the product fermented by L. edodes and P. ostreatus was applied microbiological method for growth of Enterococcus zimogenes verifying that after fermentation the protein quality was 76 and 27.4% with L. edodes and P.ostreatus, respectively, compared with casein. The quantification of amino acids showed significant improvement of protein with altered amino acid profile with treatments of fungos. About of DQO and BOD were also found considerable improvement besides considerable drop in toxicity as measured by acute toxicity test with Daphinia similis

Períodos de interferência de Mucuna aterrima (Piper & Tracy) em cana-de-açúcar e seu controle químico

Pós-graduação em Agronomia (Produção Vegetal) - FCAV