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Search Results: 1 - 10 of 55080 matches for " Messias Borges Silva "
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Project Based Learning Applied to Technical Drawing  [PDF]
Eduardo Ferro dos Santos, Bruna Caroline Marques Gon?alves, Karine Borges de Oliveira, Messias Borges Silva
Creative Education (CE) , 2018, DOI: 10.4236/ce.2018.93034
Abstract: New technological advances have been challenging professionals in education area to reach the new generation of students. Since this new generation is surrounded by this new technology, it is mandatory to associate new practices and teaching methods to their education plan. In this way, educators must reflect not only on their usual pedagogical practices but also in the efficacy of the method that has been practiced in the teaching and learning process. Technical Drawing is a discipline that takes place in High School programs in addition to Technical and Higher Education. It is directly influenced by this technological advance, once the student goes from the draw in the paper to the draw in computers during the classes and is encouraged to execute the projects that arise from the step-by-step draw. In this context, this work aimed to show a study performed during the Technical Drawing discipline to report a new structure in the educational methodology related to project-based learning. The focus of this study was to encourage students to develop a greater interest in engineering using project based learning and use this as a method for learning.
Formation of TiO2 Nanotube Layer by Anodization of Titanium in Ethylene Glycol-H2O Electrolyte  [PDF]
Alain Robin, Michele Bernardes de Almeida Ribeiro, Jorge Luiz Rosa, Roberto Zenhei Nakazato, Messias Borges Silva
Journal of Surface Engineered Materials and Advanced Technology (JSEMAT) , 2014, DOI: 10.4236/jsemat.2014.43016

In orthopaedics and orthodontics, the growth of nanotubes of titanium oxide on titanium implants is a promising route for improving the osseointegration. Among the fabrication routes to produce nanotubes, anodization was generally preferred due to its simplicity and low cost. TiO2 nanotubes are formed by the simultaneous anodic reaction and chemical dissolution due to the fluoride species present in the anodization bath. In this work, the formation of TiO2 nanotubes was studied in stirred ethylene glycol-H2O electrolyte (90 - 10 v/v) containing NH4F at room temperature. In order to study the effect of NH4F concentration, voltage and anodization time, and to reduce the number of experiments, a design of experiments (DOE) based on a 2k factorial design with four replicates at the center point was used. The analysis of variance (ANOVA) was used to evaluate the effects of the factors of control and their interactions on the percentage of the titanium surface coated by nanotubes. The dimensions of nanotubes (length and diameter) were also evaluated using field emission gun scanning electron microscopy. The cristallinity and phase composition of the oxide layers was investigated by X-ray diffractometry. The electrochemical behavior of as-received and anodized titanium specimens was studied in Ringer’s solution. The statistical analysis showed that fluoride concentration is the most significant factor. The best condition according to the response surface analysis is the center point (1% NH4F, 20 V, 2 h). The nanotubular oxide layers presented an amorphous structure. Electrochemical tests showed that TiO2 nanotubes coated titanium is less corrosion resistant than

An Application of the Taguchi Method (Robust Design) to Environmental Engineering: Evaluating Advanced Oxidative Processes in Polyester-Resin Wastewater Treatment  [PDF]
Messias Borges Silva, Livia Melo Carneiro, João Paulo Alves Silva, Ivy dos Santos Oliveira, Hélcio José Izário Filho, Carlos Roberto de Oliveira Almeida
American Journal of Analytical Chemistry (AJAC) , 2014, DOI: 10.4236/ajac.2014.513092
Abstract: This paper presents the Taguchi Method, a statistical design modelling for experiments applied in environmental engineering. This method was applied to optimize the treatment conditions of polyester-resin effluent by means of Advanced Oxidative Processes (AOPs) using chemical oxygen demand (COD) as response parameter. The influence of each independent parameter including respective interactions was evaluated by Taguchi Method, which allowed determining the most statistically significant variables and conditions to best fit the process. Results showed that Taguchi Method is a very useful tool for environmental engineering field and possible simplifications of analysis and calculations through commercially available software.
Avalia??o das condi??es reacionais para a síntese enzimática do butirato de butila empregando lipase de Candida rugosa
Gomes, Fabrício Maciel;Silva, Messias Borges da;Castro, Heizir Ferreira de;
Revista Brasileira de Ciências Farmacêuticas , 2004, DOI: 10.1590/S1516-93322004000200007
Abstract: free lipase from candida rugosa was used for the synthesis of butyl butyrate by direct esterification of butyric acid and butyl alcohol. a full factorial experimental design (24) was employed to determine the effect of alcohol to acid ratio (1: 0.5-2.5), water adsorbent concentration (0-20%), enzyme concentration (40-80 mg) and incubation temperature (30-60 °c) on the esterification yield. water adsorbent concentration has been found to be the most significant factor on the esterification reaction and its influence was negative. the extent of esterification was higher for substrates containing acid in excess even with a low enzyme concentration of 40 mg and 50% conversion was observed. the maximum predicted values for butyl butyrate yield (92.67%) can be attained with substrate containing acid in excess (molar ratio alcohol to acid 1:2.5), 80 mg enzyme concentration in the absence of water adsorbent at temperature incubation of 30 °c.
Avalia o da intera o de Zinco, Alumínio, Cobre e Manganês em Chromobacterium violaceum
Tania Cristina Sumita,Rogerio Santos Pereira,Messias Borges Silva,Luis Carlos Laureano da Rosa
Ambiente e água : An Interdisciplinary Journal of Applied Science , 2007,
Abstract: Os metais tra os liberados por atividades extrativistas, mineralógicas, industriais, agroindustriais e pelos resíduos urbanos acumulam-se no meio ambiente, afetando o equilíbrio dinamico dos ecossistemas onde est o presentes, gerando n o apenas um problema ambiental, mas também econ mico. Com foco no potencial biotecnológico de Chromobacterium violaceum, o objetivo deste trabalho foi avaliar a resistência dessa cepa a quatro sais metálicos: sulfato de alumínio, sulfato de cobre, sulfato de manganês e sulfato de zinco, bem como um possível efeito de intera o de 2a ordem, utilizando um planejamento fatorial completo 24. Para todos os sais estudados, usou-se a concentra o de 100mg/L ou a ausência do sal. Em uma microplaca de cultura com 96 orifícios, foram realizados os 16 experimentos, em duplicata. Uma suspens o do microrganismo foi preparada como inóculo e diluída em Caldo Nutriente para ser adicionada aos orifícios. Após 24 horas de incuba o a 37oC, foi realizada a leitura da absorbancia a 410nm em leitora de microplacas Versamax. Os resultados mostraram alta capacidade de adapta o de C. violaceum aos sais estudados. A análise dos resultados pelo teste t de Student mostrou que o Manganês foi o único metal que n o teve efeito significativo sobre o crescimento de C. violaceum, enquanto o Zinco foi o mais ativo, sendo observadas intera es positivas envolvendo a presen a do Zinco; a intera o entre Alumínio e Cobre n o foi relevante.
Utiliza??o de diferentes tipos de policloretos de alumínio para purifica??o de hidrolisado de baga?o de cana através da técnica de coagula??o e flocula??o
Noronha, Leonardo de Lima;Fonseca, Christiane Reis;Silva, Cássia Cavalcanti da;Silva, Messias Borges;Faria, Luís Fernando Figueiredo;
Química Nova , 2010, DOI: 10.1590/S0100-40422010000800015
Abstract: in order to investigate the action of the flocculating agents panfloc and panclar a full factorial design 23 and a central composite design 22 were carried out. the control variables were the flocculant concentration, ph and temperature. the response variables were phenolic compounds reduction and spectral area reduction. the best conditions of treatment was hydrolyzate at ph 9 for both coagulants, but the use of panfloc was more effective in the phenolic compounds reduction (73.9%) and spectral area reduction (65.8%).
A DOE based approach for the design of RBF artificial neural networks applied to prediction of surface roughness in AISI 52100 hardened steel turning
Pontes, Fabrício José;Silva, Messias Borges;Ferreira, Jo?o Roberto;Paiva, Anderson Paulo de;Balestrassi, Pedro Paulo;Sch?nhorst, Gustavo Bonnard;
Journal of the Brazilian Society of Mechanical Sciences and Engineering , 2010, DOI: 10.1590/S1678-58782010000500010
Abstract: the use of artificial neural networks for prediction in hard turning has received considerable attention in literature. an often quoted drawback of anns is the lack of a systematic way for the design of high performance networks. this study presents a doe based approach for the design of anns of radial basis function (rbf) architecture applied to surface roughness prediction in turning of aisi 52100 hardened steel. experimental factors are the number of radial units on the hidden layer, the algorithm employed to calculate the spread factor of radial units and the algorithm employed to calculate radial function centers. doe is employed to select levels of factors that benefit network prediction skills. experiments with data sets of distinct sizes were conducted and network configurations leading to high performance were identified. ann models obtained proved capable to predict roughness in accurate, precise and affordable way. results pointed significant factors for network design and revealed that interaction effects between design parameters have significant influence on network performance for the task proposed. the work concludes that the doe methodology constitutes a better approach to the design of rbf networks for roughness prediction than the most common trial and error approach.
The Application of Response Surface Methodology in the Study of Photodegraded Industrial Dairy Effluents by the Photo-Fenton Process: Optimization and Economic Viability
Carla Cristina Almeida Loures,Hélcio José Izário Filho,Ivy dos Santos Oliveira,Gisella Rossana Lamas Samanamud,André Luiz de Souza,Messias Borges Silva
ISRN Chemical Engineering , 2014, DOI: 10.1155/2014/967534
Abstract: This study presents results from an application of Photo-Fenton process for organic-load reduction in dairy effluents. Process efficiency was evaluated in terms of percentage dissolved organic carbon, chemical oxygen demand, and biochemical oxygen demand (DOC, COD, and BOD, resp.), whose initial values were ?mg?O2?L?1, ?mg?O2 L?1, and ?mg?O2?L?1, respectively. We applied a statistical design represented by Box-Behnken factorial design inclusive of Fenton's reagent, the power of applied radiation (W), and pH factors. The set temperature value was 30°C with a reaction time of 60?min. The maximum efficiency obtained was at , Fenton reagent in the proportion of 35?g H2O2? ?3.6?g Fe2+, and ultraviolet radiation potency of 28?W. The results obtained for DOC, COD, and BOD were 81%, 90.7%, and 78.8%, respectively. Regarding the cost/benefit evaluation, the variables and their levels should be the following: pH 3.5, 35.0?g H2O2/Fe2+ 3.6?g, and 28?W?UV, obtaining a reduction in concentration of 79.5% DOC. 1. Introduction Dairy industry effluents are characterized by high volumes of water consumption and elevated organic contents and inhibited recalcitrancy for a conventional treatment [1]. The escape into the aqueous environment of such pollutants, defined as industry-relevant organic components and BOD, COD, pH, fats, and phosphates, among others, demands treatment formulas that minimize the devastating impact of effluent pollution inclusive of degraded waterways, harmed environment, and a general detriment to animal and human health [2, 3]. Economically advantageous biological processes are typically used for dairy effluent treatments regardless of a series of practical limitations [4, 5]. A common problem in this methodology is the oscillation of the organic load in the dairy effluent, resulting in expanded sludge volume and compromises to the efficiency of biological processes [5]. POAs are defined as processes with considerable capacity for hydroxyl radical (?OH) production [6, 7]. A high standard reduction potential (see (1)) for this radical is capable of oxidizing a wide variety of organic compounds to CO2, H2O, and inorganic ions from heteroatoms: Among the POAs, the use of Fe2+/Fe3+ in the presence of hydrogen peroxide under irradiation, called a Photo-Fenton reaction, is considered the most promising for remediation of effluents containing a variety of toxic nonbiodegradable organic compounds [8, 9]. Several industrial effluent treatment studies using this process have been made in recent decades [5, 8–11]. Using a process parameter optimization, the
Migra??o e hanseníase em Mato Grosso
Magalh?es, Maria da Concei??o Cavalcanti;Santos, Emerson Soares dos;Queiroz, Maria de Lourdes de;Lima, Messias Lucas de;Borges, Rita Christina Martins;Souza, Maria Silva;Ramos, Alberto Novaes;
Revista Brasileira de Epidemiologia , 2011, DOI: 10.1590/S1415-790X2011000300004
Abstract: studies on medical geography about leprosy discuss the role of the detailed report of the occupation of the territories as a basis of the permanence of leprosy focus. in brazil, the states that present the highest rates of detection historically are in the amazon region, which shows an uneven regional evolution of the disease. this paper analyzes the evolution of leprosy contextualizing the migratory processes that occurred in the state of mato grosso since the second half of the 20th century. the economic dynamism that occurred in the state in the 1970s, 1980s and 1990s caused population growth rates higher than the national average. the data analyzed permitted an association between the evolution of leprosy and the process of occupation of the mato-grossense territory. however, the permanence of leprosy in the municipalities of the baixada cuiabana, as well as in other municipalities that lost population, seem to point to the existence of geographic contexts of different vulnerability to the social production of the disease in the tate. the migration would explain the appearance and evolution of leprosy. however, we consider that the maintenance of the endemic can be associated to contextual factors related to environment.
Cutaneous Tuberculosis and AIDS Diagnosis: A Case Report  [PDF]
Gisela Borges, Maria de Jesus Silva
Case Reports in Clinical Medicine (CRCM) , 2018, DOI: 10.4236/crcm.2018.72010
Abstract: The incidence of extrapulmonary tuberculosis has been increasing especially among immunocompromised patients. Mycobacterium tuberculosis skin infection is rare, accounting for 1.5% of all forms of the disease. We present a clinical case of 38 years old woman, Brazilian; with sexual risk behaviours that develops a sudden thoracoabdominal tumefaction of 4 - 5 cm. The investigation confirmed a metastatic tuberculous abscess in a patient with acquired immunodeficiency syndrome.
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