24 resultados para TENORIO, OTILINIO

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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This work addresses the synthesis of carbon nanomaterials (CNMs) by up-cycling common solid wastes. These feedstocks could supersede the use of costly and often toxic or highly flammable chemicals, such as hydrocarbon gases, carbon monoxide, and hydrogen, which are commonly used as feedstocks in current nanomanufacturing processes for CNMs. Agricultural sugar cane bagasse and corn residues, scrap tire chips, and postconsumer polyethylene (PE) and polyethylene terephthalate (PET) bottle shreddings were either thermally treated by sole pyrolysis or by sequential pyrolysis and partial oxidation. The resulting gaseous carbon-bearing effluents were then channeled into a heated reactor. CNMs, including carbon nanotubes, were catalytically synthesized therein on stainless steel meshes. This work revealed that the structure of the resulting CNMs is determined by the feedstock type, through the disparate mixtures of carbon-bearing gases generated when different feedstocks are pyrolyzed. CNM characterization was conducted by scanning and transmission electron microscopy as well as by Raman spectroscopy and by thermogravimetric analysis. Gas chromatography was used to characterize the gases in the synthesis chamber. This work demonstrated an alternative method for efficient manufacturing of CNMs using both biodegradable and nonbiodegradable agricultural and municipal carbonaceous wastes.

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VIEIRA, R. D. P., A. C. TOLEDO, L. B. SILVA, F. M. ALMEIDA, N. R. DAMACENO-RODRIGUES, E. G. CALDINI, A. B. G. SANTOS, D. H. RIVERO, D. C. HIZUME, F. D. T. Q. S. LOPES, C. R. OLIVO, H. C. CASTRO-FARIA-NETO, M. A. MARTINS, P. H. N. SALDIVA, and M. DOLHNIKOFF. Anti-inflammatory Effects of Aerobic Exercise in Mice Exposed to Air Pollution. Med. Sci. Sports Exerc., Vol. 44, No. 7, pp. 1227-1234, 2012. Purpose: Exposure to diesel exhaust particles (DEP) results in lung inflammation. Regular aerobic exercise improves the inflammatory status in different pulmonary diseases. However, the effects of long-term aerobic exercise on the pulmonary response to DEP have not been investigated. The present study evaluated the effect of aerobic conditioning on the pulmonary inflammatory and oxidative responses of mice exposed to DEP. Methods: BALB/c mice were subjected to aerobic exercise five times per week for 5 wk, concomitantly with exposure to DEP (3 mg.mL (1); 10 mu L per mouse). The levels of exhaled nitric oxide, reactive oxygen species, cellularity, interleukin 6 (IL-6), and tumor necrosis factor alpha (TNF-alpha) were analyzed in bronchoalveolar lavage fluid, and the density of neutrophils and the volume proportion of collagen fibers were measured in the lung parenchyma. The cellular density of leukocytes expressing IL-1 beta, keratinocyte chemoattractant (KC), and TNF-alpha in lung parenchyma was evaluated with immunohistochemistry. The levels of IL-1 beta, KC, and TNF-alpha were also evaluated in the serum. Results: Aerobic exercise inhibited the DEP-induced increase in the levels of reactive oxygen species (P < 0.05); exhaled nitric oxide (P < 0.01); total (P < 0.01) and differential cells (P < 0.01); IL-6 and TNF-alpha levels in bronchoalveolar lavage fluid (P < 0.05); the level of neutrophils (P < 0.001); collagen density in the lung parenchyma (P < 0.05); the levels of IL-6, KC, and TNF-alpha in plasma (P < 0.05); and the expression of IL-1 beta, KC, and TNF-alpha by leukocytes in the lung parenchyma (P < 0.01). Conclusions: We conclude that long-term aerobic exercise presents protective effects in a mouse model of DEP-induced lung inflammation. Our results indicate a need for human studies that evaluate the pulmonary responses to aerobic exercise chronically performed in polluted areas.

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Batch combustion of fixed beds of coal, bagasse and blends thereof took place in a pre-heated two-stage electric laboratory furnace, under high-heating rates. The average input fuel/air equivalence ratios were similar for all fuels. The primary and secondary furnace temperatures were varied from 800 degrees C to 1000 degrees C. The effects of fuel blending, combustion staging, and operating furnace temperatures on the emissions from the two fuels were assessed. Furnace effluents were analyzed for carbon dioxide and for products of incomplete combustion (PIC) including CO, volatile and semi-volatile hydrocarbons, as well as particulate matter. Results showed that whereas CO2 was generated during both the observed sequential volatile matter and char combustion phases of the fuels, PICs were only generated during the volatile matter combustion phase. CO2 emissions were the highest from coal, whereas CO and other PIC emissions were the highest from bagasse. Under this particular combustion configuration, combustion of the volatile matter of the blends resulted in lower yields of PIC, than combustion of the volatiles of the neat fuels. Though CO and unburned hydrocarbons from coal as well as from the blends did not exhibit a clear trend with furnace temperature, such emissions from bagasse clearly increased with temperature. The presence of the secondary furnace (afterburner) typically reduced PIC, by promoting further oxidation of the primary furnace effluents. (C) 2012 Elsevier Ltd. All rights reserved.

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This work reports on emissions of unburned hydrocarbon species from batch combustion of fixed beds of coal, sugar-cane bagasse, and blends thereof in a pre-heated two-stage laboratory furnace operated in the temperature range of 800-1000 degrees C. The effects of fuel blending, combustion staging, and operating furnace temperatures on emissions of pollutants were assessed. Furnace effluents were analyzed for products of incomplete combustion (PICs) including CO, volatile and semi-volatile hydrocarbons, and particulate matter, as has been reported in Ref. [1]. Emitted unburned hydrocarbons include traces of potentially health-hazardous Polycyclic Aromatic Hydrocarbons (PAHs), which are the focus of this work. Under the batch combustion conditions implemented herein, PAH were only generated during the volatile combustion phase of the fuels. The most prevalent species were in descending order: naphthalene, acenaphthylene, phenanthrene, fluoranthene, pyrene, dibenzofuran, benzofuran, byphenyl, fluorene, 9H-fluoren-9-one, acephenantrylene, benzo[b] fluoranthene, 1-methyl-naphthalene; 2-methyl-naphthalene, benz[a] anthracene and benzo[a] pyrene. PAH yields were the highest from combustion of neat bagasse. Combustion of the blends resulted in lower yields of PAH, than combustion of either of their neat fuel constituents. Increasing the furnace operating temperature enhanced the PAH emissions from bagasse, but had little effect on those from the coal or from the blends. Flue gas treatment in a secondary-stage furnace, upon with additional air, typically reduced PAH yields by promoting oxidation of the primary-stage furnace effluents. (C) 2011 Elsevier Ltd. All rights reserved.

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Syntesis of carbon nanomaterials from corn waste (DDGS). The world's largest ethanol producer (USA) uses corn as feedstock. DDGS (distillers dried grains with solubles) is the main waste generated from this process (around 32 million t/year). DDGS samples were pyrolyzed at 1000 degrees C in a furnace with controlled atmosphere. The effluent was channeled to a second furnace, in which catalyst substrates were placed. Chromatographic analysis was used to evaluate the gaseous effluents, showing that the catalyst reduced hydrocarbon emissions. The solid products formed were analyzed by SEM and TEM. Graphitic structures and carbon nanofibers, 50 mu m in length and with diameters of 80-200 nm, were formed.

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Family Health Support Centers (NASF) were created in Brazil to increase the case-resolution capacity of primary healthcare. Prior to their implementation in the West Side of the city of Sao Paulo, Brazil, a series of workshops were held for primary healthcare professionals to prepare a proposal for such centers. Hermeneutic analysis was used to study the transcribed material. The thematic categories were: role, constitution, and functioning of the NASF, relationship with family health teams, and interdisciplinarity. The participants' expected the NASF to be an empowering device for comprehensiveness of care, intervening in an existing culture of unnecessary referrals while fostering linkage with other levels of care. The participants also expected the NASF to contribute to the discussion on health professionals' training and stimulating reflection with policy-makers on health indicators based exclusively on the number of consultations. These indicators fail to reflect the impact on the services' activities and the quality of care offered to the population in the coverage area.

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The role of innate immune response in protection against leptospirosis is poorly understood. We examined the expression of the chemokine CXCL2/MIP-2 and the cytokine TNF-alpha. in experimental resistant and susceptible mice models, C3H/HeJ, C3H/HePas and BALB/c strains, using a virulent strain of Leptospira interrogans serovar Copenhageni. Animals were infected intraperitoneally with 107 cells and the development of the disease was followed. Mortality of C3H/HeJ mice was observed whereas C3H/HePas presented jaundice and BALB/c mice remained asymptomatic. The infection was confirmed by the presence of leptospiral DNA in the organs of the animals, demonstrated by PCR. Sections of the organs were analyzed, after H&E stain. The relative expression of mRNA of chemokine CXCL2/MIP-2 and cytokine TNF-alpha was measured in lung, kidney and liver of the mice by qPCR. The concentrations of these proteins were measured in extracts of tissues and in serum of the animals, by ELISA. Increasing levels of transcripts and protein CXCL2/MIP-2 were detected since the first day of infection. The highest expression was observed at third day of infection in kidney, liver and lung of BALB/c mice. In C3H/HeJ the expression of CXCL2/MIP-2 was delayed, showing highest protein concentration in lung and kidney at the 5th day. Increasing in TNF-alpha transcripts were detected after infection, in kidney and liver of animals from the three mice strains. The expression of TNF-alpha protein in C3H/HeJ was also delayed, being detected in kidney and lung. Our data demonstrated that Leptospira infection stimulates early expression of CXCL2/MIP-2 and TNF-alpha in the resistant strain of mice. Histological analysis suggests that the expression of those molecules may be related to the influx of distinct immune cells and plays a role in the naturally acquired protective immunity. (C) 2012 Elsevier Ltd. All rights reserved.

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Campos R, Shimizu MH, Volpini RA, de Bragan a AC, Andrade L, Lopes FD, Olivo C, Canale D, Seguro AC. N-acetylcysteine prevents pulmonary edema and acute kidney injury in rats with sepsis submitted to mechanical ventilation. Am J Physiol Lung Cell Mol Physiol 302: L640-L650, 2012. First published January 20, 2012; doi: 10.1152/ajplung.00097.2011.-Sepsis is a common cause of acute kidney injury (AKI) and acute lung injury. Oxidative stress plays as important role in such injury. The aim of this study was to evaluate the effects that the potent antioxidant N-acetylcysteine (NAC) has on renal and pulmonary function in rats with sepsis. Rats, treated or not with NAC (4.8 g/l in drinking water), underwent cecal ligation and puncture (CLP) 2 days after the initiation of NAC treatment, which was maintained throughout the study. At 24 h post-CLP, renal and pulmonary function were studied in four groups: control, control + NAC, CLP, and CLP + NAC. All animals were submitted to low-tidal-volume mechanical ventilation. We evaluated respiratory mechanics, the sodium cotransporters Na-K-2Cl (NKCC1) and the alpha-subunit of the epithelial sodium channel (alpha-ENaC), polymorphonuclear neutrophils, the edema index, oxidative stress (plasma thiobarbituric acid reactive substances and lung tissue 8-isoprostane), and glomerular filtration rate. The CLP rats developed AKI, which was ameliorated in the CLP + NAC rats. Sepsis-induced alterations in respiratory mechanics were also ameliorated by NAC. Edema indexes were lower in the CLP + NAC group, as was the wet-to-dry lung weight ratio. In CLP + NAC rats, alpha-ENaC expression was upregulated, whereas that of NKCC1 was downregulated, although the difference was not significant. In the CLP + NAC group, oxidative stress was significantly lower and survival rates were significantly higher than in the CLP group. The protective effects of NAC (against kidney and lung injury) are likely attributable to the decrease in oxidative stress, suggesting that NAC can be useful in the treatment of sepsis.

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The aim of the present study is to contribute an ecologically relevant assessment of the ecotoxicological effects of pesticide applications in agricultural areas in the tropics, using an integrated approach with information gathered from soil and aquatic compartments. Carbofuran, an insecticide/nematicide used widely on sugarcane crops, was selected as a model substance. To evaluate the toxic effects of pesticide spraying for soil biota, as well as the potential indirect effects on aquatic biota resulting from surface runoff and/or leaching, field and laboratory (using a cost-effective simulator of pesticide applications) trials were performed. Standard ecotoxicological tests were performed with soil (Eisenia andrei, Folsomia candida, and Enchytraeus crypticus) and aquatic (Ceriodaphnia silvestrii) organisms, using serial dilutions of soil, eluate, leachate, and runoff samples. Among soil organisms, sensitivity was found to be E. crypticus < E. andrei < F. candida. Among the aqueous extracts, mortality of C. silvestrii was extreme in runoff samples, whereas eluates were by far the least toxic samples. A generally higher toxicity was found in the bioassays performed with samples from the field trial, indicating the need for improvements in the laboratory simulator. However, the tool developed proved to be valuable in evaluating the toxic effects of pesticide spraying in soils and the potential risks for aquatic compartments. Environ. Toxicol. Chem. 2012;31:437-445. (C) 2011 SETAC

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Removal of Mg from aluminum scraps, known as demagging, has been widely applied in the,aluminum industry. This work discusses bubble-formation theories and magnesium kinetic removal from aluminum scraps using chlorine and inert gas fluxing. The interfacial area of the bubbles and residence time were estimated using a mathematical model. To inject gaseous chlorine, three types of nozzles were used with varying internal diameter. In addition, a porous plug, as well as varying input chlorine flow and concentration were used. The use of lower chlorine concentration improves efficiency because the interfacial tension is reduced therefore, more and smaller bubbles are formed. The model proposed herein is consistent with the experimental data. [doi:10.2320/matertrans.M2011256]

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Dengue fever is a mosquito-borne viral disease estimated to cause about 230 million infections worldwide every year, of which 25,000 are fatal. Global incidence has risen rapidly in recent decades with some 3.6 billion people, over half of the world's population, now at risk, mainly in urban centres of the tropics and subtropics. Demographic and societal changes, in particular urbanization, globalization, and increased international travel, are major contributors to the rise in incidence and geographic expansion of dengue infections. Major research gaps continue to hamper the control of dengue. The European Commission launched a call under the 7th Framework Programme with the title of 'Comprehensive control of Dengue fever under changing climatic conditions'. Fourteen partners from several countries in Europe, Asia, and South America formed a consortium named 'DengueTools' to respond to the call to achieve better diagnosis, surveillance, prevention, and predictive models and improve our understanding of the spread of dengue to previously uninfected regions (including Europe) in the context of globalization and climate change. The consortium comprises 12 work packages to address a set of research questions in three areas: Research area 1: Develop a comprehensive early warning and surveillance system that has predictive capability for epidemic dengue and benefits from novel tools for laboratory diagnosis and vector monitoring. Research area 2: Develop novel strategies to prevent dengue in children. Research area 3: Understand and predict the risk of global spread of dengue, in particular the risk of introduction and establishment in Europe, within the context of parameters of vectorial capacity, global mobility, and climate change. In this paper, we report on the rationale and specific study objectives of 'DengueTools'. DengueTools is funded under the Health theme of the Seventh Framework Programme of the European Community, Grant Agreement Number: 282589 Dengue Tools.

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The deep-water molluscs collected during the expedition MD55 off SE Brazil have been gradually studied in some previous papers. The present one is focused on samples belonging to caenogastropod taxa Xenophoridae Troschel, 1852, Cypraeoidea Rafinesque, 1815, mitriforms and Terebridae Morch, 1852. Regarding the Xenophoridae, Onustus aquitanus n. sp. is a new species, collected off the littoral of Espirito Santo and Rio de Janeiro, Brazil, 430-637 m depth (continental slope). The main characters of the species include the small size (c. 20 mm), the proportionally wide shell, the white colour, the short peripheral flange, the oblique riblets weakly developed and a brown multispiral protoconch. This appears to be the smallest living species of the family, resembling in this aspect fossil species. In respect to the Cypraeoidea, the following results were obtained: family Cypraeidae Rafinesque, 1815: Erosaria acicularis (Gmelin, 1791) and Luria cinerea (Gmelin, 1791) had the deepest record, respectively 607-620 m and 295-940 m, although the samples were all dead, eroded shells. Family Lamellariidae d'Orbigny, 1841: a total of three lots were collected, provisionally identified as Lamellaria spp. as the samples consist of only vestigial shells; possibly each lot represents a different species. Family Pediculariidae Gray, 1853: a sample of Pedicularia tibia Simone, 2005 was found, expanding the range c. 1000 km southwards, from Ceara to Espirito Santo. Family Ovulidae Fleming, 1822: Pseudosimnia lacrima n. sp., collected off Espirito Santo, 607-620 m depth, is described here and is mainly characterised by its strong biconic outline, small size (c. 7 mm), and a thick peripheral callus. Family Triviidae Troschel, 1863: Cleotrivia antillarum (Schilder, 1922) is recorded for the first time as deep as 620 m, and its distribution expanded from Rio Grande do Norte to Espirito Santo; Dolichupis akangus n. sp. with rounded outline and c. 15 transverse ribs; D. pingius n. sp. with the outer lip expanded posteriorly and c. 10 ribs. In respect to the mitriform neogastropods, the following species are emphasised: family Costellariidae MacDonald, 1860: Vexillum sp., 607-620 m depth; Turricostellaria amphissa n. sp., 295 m depth; T. jukyry n. sp.; T. apyrahi n. sp., both 790-1575 m depth; T. ovir n. sp., 1200 m depth; Nodicostellaria crassa (Simone, 1995), 240-600 m depth, with extension northwards of the range up to Espirito Santo; Austromitra decresca n. sp., 60-105 m depth. Family Mitridae Swainson, 1829: Subcancilla joapyra n. sp., 295 m depth; S. cf. straminea (Adams, 1853), 607-620 m depth. Family Volutomitridae Gray, 1854: Microvoluta corona n. sp., 1500-1575 m depth. Family Mitromorphidae Casey, 1904: Mitromorpha sama n. sp., 607-940 m depth; M. mirim n. sp., 60105 m depth. Regarding the conoidean Terebridae, this paper is a complement of a previous study. It deals with a new species Terebra assu Simone n. sp., from the Abrolhos Bank, 295 m depth, characterised by its narrow outline, yellowish colour, weak sculpture on the last whorls, and a proportionally broad, paucispiral protoconch. A second finding of Terebra alagoensis Lima, Tenorio & Barros, 2007 expands the geographic range from Alagoas to north Espirito Santo. A discussion on the systematics of the "complex Terebra doellojuradoi" in South American coast is also provided, highlighting the improbability of synonymy between T. leptapsis Simone, 1999 and T doellojuradoi Carcelles, 1953. Differences in size, sculpture, spire angulation, aperture, and mainly in protoconch, indicate specific separations. The presently studied terebrids belong to the "complex Terebra doellojuradoi", which encompasses closely related, deep-water, small species, possessing a relatively high degree of endemicity.

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The world's largest ethanol producer (USA) uses corn as feedstock. DDGS (distillers dried grains with solubles) is the main waste generated from this process (around 32 million t/year). DDGS samples were pyrolyzed at 1000 ºC in a furnace with controlled atmosphere. The effluent was channeled to a second furnace, in which catalyst substrates were placed. Chromatographic analysis was used to evaluate the gaseous effluents, showing that the catalyst reduced hydrocarbon emissions. The solid products formed were analyzed by SEM and TEM. Graphitic structures and carbon nanofibers, 50 µm in length and with diameters of 80-200 nm, were formed.

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As fibras cerâmicas se caracterizam por ser um material leve, com alto grau de pureza, baixo armazenamento de calor, baixa condutividade térmica, resistência a choque térmico e alta resistência à corrosão em altas temperaturas. Essas características levam a uma grande procura das indústrias mínero-metalúrgicas e de outros setores para revestimentos de distribuidores, muflas, fornos de aquecimentos, entre outros. Após utilização no processo, por perderem sua capacidade de isolamento, os resíduos gerados precisam de destinação. Esse trabalho enfoca, especificamente, resíduos de lã cerâmica e lã de vidro. Pelo fato de a composição das fibras cerâmicas ser rica em sílica e alumina, efetuou-se uma investigação acerca da atividade pozolânica das mesmas com a cal e o cimento, especificamente CPV ARI, CPII E32 e CPIII 32RS, para avaliação da perspectiva de reciclagem em possível incorporação no concreto.

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The objective of this paper is to present an analysis of the use of residual marble mixtures in the pig iron desulfurization process. The study involved the use of: marble waste, fluorspar, lime, and hot metal. Four mixtures were made and added to a liquid hot metal - with known chemical composition - at a temperature of 1450ºC. The mass of each element was calculated from its chemical analysis and compared with an industrial mixture. All of the four mixtures used in the experiments were stirred by a mechanical stirrer. Samples were collected by vacuum sampling for times of 5, 10, 15, 20, and 30 minutes, and analysis was performed to check sulfur variation in the bath with time. The results were analyzed and they verified that it was possible to use marble waste as a desulfurizer.