988 resultados para Eduardo Campos


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We investigate the cosmology of the vacuum energy decaying into cold dark matter according to thermodynamics description of Alcaniz & Lima. We apply this model to analyze the evolution of primordial density perturbations in the matter that gave rise to the first generation of structures bounded by gravity in the Universe, called Population III Objects. The analysis of the dynamics of those systems will involve the calculation of a differential equation system governing the evolution of perturbations to the case of two coupled fluids (dark matter and baryonic matter), modeled with a Top-Hat profile based in the perturbation of the hydrodynamics equations, an efficient analytical tool to study the properties of dark energy models such as the behavior of the linear growth factor and the linear growth index, physical quantities closely related to the fields of peculiar velocities at any time, for different models of dark energy. The properties and the dynamics of current Universe are analyzed through the exact analytical form of the linear growth factor of density fluctuations, taking into account the influence of several physical cooling mechanisms acting on the density fluctuations of the baryonic component of matter during the evolution of the clouds of matter, studied from the primordial hydrogen recombination. This study is naturally extended to more general models of dark energy with constant equation of state parameter in a flat Universe

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It is known that sleep plays an important role in the process of motor learning. Recent studies have shown that the presence of sleep between training a motor task and retention test promotes a learning task so than the presence of only awake between training and testing. These findings also have been reported in stroke patients, however, there are few studies that investigate the results of this relationship on the functionality itself in this population. The objective of this study was to evaluate the relationship between functionality and sleep in patients in the chronic stage of stroke. A cross-sectional observational study was conducted. The sample was composed of 30 stroke individuals in chronic phase, between 6 and 60 months after injury and aged between 55 and 75 years. The volunteers were initially evaluated for clinical data of disease and personal history, severity of stroke, through the National Institute of Health Stroke Scale, and mental status, the Mini-Mental State Examination. Sleep assessment tools were Pittsburgh Sleep Quality Index, the Questionnaire of Horne and Ostberg, Epworth Sleepiness Scale, the Berlin questionnaire and actigraphy, which measures were: real time of sleep, waking after sleep onset, percentage of waking after sleep onset, sleep efficiency, sleep latency, sleep fragmentation index, mean activity score. Other actigraphy measures were intraday variability, stability interdiária, a 5-hour period with minimum level of activity (L5) and 10-hour period with maximum activity (M10), obtained to evaluate the activity-rest rhythm. The Functional Independence Measure (FIM) and the Berg Balance Scale (BBS) were the instruments used to evaluate the functional status of participants. The Spearman correlation coefficient and comparison tests (Student's t and Mann-Whitney) were used to analyze the relationship of sleep assessment tools and rest-activity rhythm to measures of functional assessment. The SPSS 16.0 was used for analysis, adopting a significance level of 5%. The main results observed were a negative correlation between sleepiness and balance and a negative correlation between the level of activity (M10) and sleep fragmentation. No measurement of sleep or rhythm was associated with functional independence measure. These findings suggest that there may be an association between sleepiness and xii balance in patients in the chronic stage of stroke, and that obtaining a higher level of activity may be associated with a better sleep pattern and rhythm more stable and less fragmented. Future studies should evaluate the cause-effect relationship between these parameters

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The aim of this study is to assess the usability of the Integrated Management System for Academic Activities (SIGAA) for the sensu stricto postgraduate programs at Universidade Federal do Rio Grande do Norte. The study was based on ergonomic criteria proposed by Bastien and Scapin (1993) and the Federal Government s Handbook of Usability (2010). The methodology used was a descriptive data survey involving an online questionnaire, and a sample of 46 system users, composed of coordinators and secretaries from the sensu stricto postgraduate programs. In addition to this procedure, open interviews were held with the users as well as a documental analysis of calls registered by them at the SIGAA between May 2012 and June 2013. Data analysis showed that a number of additional usability criteria need to be implemented, primarily related to ergonomic problems of orientation, error management and workload. Based on the analyses, several changes were proposed that may streamline secretarial activities, as well as provide greater satisfaction and interaction between the SIGAA and its users

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In this work, we present a text on the Sets Numerical using the human social needs as a tool for construction new numbers. This material is intended to present a text that reconciles the correct teaching of mathmatics and clarity needed for a good learning

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The generation of wastes in most industrial process is inevitable. In the petroleum industry, one of the greatest problems for the environment is the huge amount of produced water generated in the oil fields. This wastewater is a complex mixture and present great amounts. These effluents can be hazardous to the environmental without adequate treatment. This research is focused in the analysis of the efficiencies of the flotation and photo-oxidation processes to remove and decompose the organic compounds present in the produced water. A series of surfactants derivated from the laurilic alcohol was utilized in the flotation to promote the separation. The experiments have been performed with a synthetic wastewater, carefully prepared with xylene. The experimental data obtained using flotation presented a first order kinetic, identified by the quality of the linear data fitting. The best conditions were found at 0.029 g.L-1 for the surfactant EO 7, 0.05 g.L-1 for EO 8, 0.07 g.L-1 for EO 9, 0.045 g.L-1 for EO 10 and 0.08 g.L-1 for EO 23 with the following estimated kinetic constants: 0.1765, 0.1325, 0.1210, 0.1531 and 0.1699 min-1, respectively. For the series studied, the most suitablesurfactant was the EO 7 due to the lower reagent consumption, higher separation rate constant and higher removal efficiency of xylene in the aqueous phase (98%). Similarly to the flotation, the photo-Fenton process shows to be efficient for degradation of xylene and promoting the mineralization of the organic charge around 90% and 100% in 90 min

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Innovative technologies using surfactant materials have applicability in several industrial fields, including petroleum and gas areas. This study seeks to investigate the use of a surfactant derived from coconut oil (SCO saponified coconut oil) in the recovery process of organic compounds that are present in oily effluents from petroleum industry. For this end, experiments were accomplished in a column of small dimension objectifying to verify the influence of the surfactant SCO in the efficiency of oil removal. This way, they were prepared emulsions with amount it fastens of oil (50, 100, 200 and 400 ppm), being determined the great concentrations of surfactant for each one of them. Some rehearsals were still accomplished with produced water of the industry of the petroleum to compare the result with the one of the emulsions. According to the experiments, it was verified that an increase of the surfactant concentration does not implicate in a greater oil removal. The separation process use gaseous bubbles formed when a gas stream pass a liquid column, when low surfactant concentrations are used, it occurs the coalescence of the dispersed oil droplets and their transport to the top of the column, forming a new continuous phase. Such surfactants lead to a gas-liquid interface saturation, depending on the used surfactant concentration, affecting the flotation process and influencing in the removal capacity of the oily dispersed phase. A porous plate filter, with pore size varying from 40 to 250 mm, was placed at the base of the column to allow a hydrodynamic stable operation. During the experimental procedures, the operating volume of phase liquid was held constant and the rate of air flow varied in each experiment. The resulting experimental of the study hydrodynamic demonstrated what the capturing of the oil was influenced by diameter of the bubbles and air flow. With the increase flow of 300 about to 900 cm3.min-1, occurred an increase in the removal of oil phase of 44% about to 66% and the removal kinetic of oil was defined as a reaction of 1° order.

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Foi desenvolvido um método para detectar e quantificar misturas de corantes em sucos artificiais em pó fabricados no Brasil, de diferentes marcas e sabores. Foram estudados 6 corantes artificiais: amarelo tartrazina, amarelo crepúsculo, vermelho ponceau 4R, vermelho bordeaux S, vermelho 40 e azul brilhante presentes de forma unitária ou em misturas nos sucos com sabores laranja, tangerina, maracujá, abacaxi, limão e uva. A identificação dos corantes nas amostras foi feita através da comparação com os espectros dos padrões, utilizando-se a análise por infravermelho médio e pelos respectivos valores de absorção máxima nos comprimentos de onda relativos aos padrões e valores de referência na literatura. Também foram estudados os perfis de decomposição térmica por termogravimetria, termogravimetria derivada e calorimetria diferencial exploratória dos corantes e dos sucos em pó, sendo determinados os teores de umidade, de matéria orgânica e de cinzas. O teor de umidade encontrado não ultrapassou 4% para todas as amostras de suco analisadas. Com relação ao teor de matéria orgânica obteve-se para 57% dos sucos analisados um teor médio de 51,3% e para 43% das outras amostras obteve-se uma média de 67,2 %. Os resultados obtidos para o teor de cinzas indicaram que 29% das amostras apresentaram um teor de 26,7% para esse parâmetro enquanto 71% das amostras apresentaram um teor de cinzas de 46,4%. Os resultados obtidos por análise térmica mostraram-se adequados considerando-se que para obter os resultados pelo método tradicional há um investimento maior de tempo, de pessoal envolvido e de material, além da proteção ao meio ambiente. Para a análise por espectroscopia de absorção molecular foi proposta uma equação simplificada para a determinação de cada corante na mistura utilizando-se a lei de Beer. Para validação, empregou-se a espectroscopia de absorção molecular no visível, onde foi investigada a influência dos interferentes (TiO2 e açúcar) presentes nas amostras de sucos, os testes de fotodegradação e a avaliação do efeito do pH. Para quantificação tomou-se como referência 512 amostras sintéticas contendo um e dois corantes (1,5625 a 25,000 mg L-1) para obtenção das curvas analíticas que foram aplicadas à análise dos sucos em pó. Os resultados indicaram que o teor máximo do amarelo crepúsculo foi encontrado nos sucos com os sabores laranja, tangerina e manga que correspondeu a 25,6% da ingestão diária aceitável (para ser ultrapassada corresponderia a ingestão de 4 copos). O teor máximo encontrado para o amarelo tartrazina nos sucos foi para o sabor maracujá que correspondeu a 8,5% da ingestão diária aceitável, (para ser alcançado corresponderia a ingestão de 12 copos). O método proposto foi testado e validado com sucesso para amostras de sucos em pó sendo de simples execução e de rapidez na obtenção dos resultados

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The increasingly request for processing power during last years has pushed integrated circuit industry to look for ways of providing even more processing power with less heat dissipation, power consumption, and chip area. This goal has been achieved increasing the circuit clock, but since there are physical limits of this approach a new solution emerged as the multiprocessor system on chip (MPSoC). This approach demands new tools and basic software infrastructure to take advantage of the inherent parallelism of these architectures. The oil exploration industry has one of its firsts activities the project decision on exploring oil fields, those decisions are aided by reservoir simulations demanding high processing power, the MPSoC may offer greater performance if its parallelism can be well used. This work presents a proposal of a micro-kernel operating system and auxiliary libraries aimed to the STORM MPSoC platform analyzing its influence on the problem of reservoir simulation

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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There is a growing interest of the Computer Science education community for including testing concepts on introductory programming courses. Aiming at contributing to this issue, we introduce POPT, a Problem-Oriented Programming and Testing approach for Introductory Programming Courses. POPT main goal is to improve the traditional method of teaching introductory programming that concentrates mainly on implementation and neglects testing. POPT extends POP (Problem Oriented Programing) methodology proposed on the PhD Thesis of Andrea Mendonça (UFCG). In both methodologies POPT and POP, students skills in dealing with ill-defined problems must be developed since the first programming courses. In POPT however, students are stimulated to clarify ill-defined problem specifications, guided by de definition of test cases (in a table-like manner). This paper presents POPT, and TestBoot a tool developed to support the methodology. In order to evaluate the approach a case study and a controlled experiment (which adopted the Latin Square design) were performed. In an Introductory Programming course of Computer Science and Software Engineering Graduation Programs at the Federal University of Rio Grande do Norte, Brazil. The study results have shown that, when compared to a Blind Testing approach, POPT stimulates the implementation of programs of better external quality the first program version submitted by POPT students passed in twice the number of test cases (professor-defined ones) when compared to non-POPT students. Moreover, POPT students submitted fewer program versions and spent more time to submit the first version to the automatic evaluation system, which lead us to think that POPT students are stimulated to think better about the solution they are implementing. The controlled experiment confirmed the influence of the proposed methodology on the quality of the code developed by POPT students

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Multimedia systems must incorporate middleware concepts in order to abstract hardware and operational systems issues. Applications in those systems may be executed in different kinds of platforms, and their components need to communicate with each other. In this context, it is needed the definition of specific communication mechanisms for the transmission of information flow. This work presents a interconnection component model for distributed multimedia environments, and its implementation details. The model offers specific communication mechanisms for transmission of information flow between software components considering the Cosmos framework requirements in order to support component dynamic reconfiguration

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Multimedia systems must incorporate middleware concepts in order to abstract hardware and operational systems issues. Applications in those systems may be executed in different kinds of platforms, and their components need to communicate with each other. In this context, it is needed the definition of specific communication mechanisms for the transmission of information flow. This work presents a interconnection component model for distributed multimedia environments, and its implementation details. The model offers specific communication mechanisms for transmission of information flow between software components considering the Cosmos framework requirements in order to support component dynamic reconfiguration

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Purpose: To evaluate cigarette smoke exposure and/or diabetes association effects on the glycemia and liver glycogen levels of pregnant Wistar rats. Methods: 60 adult rats were randomly distributed into (n= 10/group): non-diabetic exposed to filtered air (G1); non-diabetic exposed to cigarette smoke only before pregnancy (G2); non-diabetic exposed to cigarette smoke before and during pregnancy (G3); diabetic exposed to filtered air (G4); diabetic exposed to cigarette smoke only before pregnancy (G5), and diabetic exposed to cigarette smoke before and during pregnancy (G6). Glycemia was determined at days 0 and 21 of pregnancy. Liver samples were collected for liver glycogen determinations. Results: At day 21 of pregnancy, glycemia was higher in G5 and G6 compared to G4 group. G2 (2.43 +/- 0.43), G3 (3.20 +/- 0.49), G4 (2.62 +/- 0.34), G5 (2.65 +/- 0.27) and G6 groups (1.94 +/- 0.35) presented decreased liver glycogen concentrations compared to G1 (4.20 +/- 0.18 mg/100mg liver tissue) (p<0.05). G5 and G6 groups presented decreased maternal weight gain and litter weight. Conclusions: Severe diabetes and cigarette smoke exposure, alone or associated, caused impairment in liver glycogen storage at term pregnancy. Due to the fact that liver glycogen storages were considered determinant for glucose tolerance, it is relevant to point out a rigid clinical glycemic control and to stop smoking so earlier in pregnancy programming.

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INTRODUÇÃO: Apesar da alta freqüência de infecção por Helicobacter pylori na população, somente uma minoria de indivíduos desenvolve câncer gástrico. É provável que a colonização da mucosa por cepas patogênicas, levando a maior agressão e inflamação da mucosa seja um dos elos da cadeia de eventos da oncogênese gástrica. OBJETIVOS: Investigar a freqüência de cepas patogênicas cagA e vacA do H. pylori em pacientes com câncer gástrico. MATERIAL E MÉTODOS: Foram estudados retrospectivamente 42 pacientes com câncer gástrico. A infecção por H. pylori foi avaliada por exame histológico e pelo PCR para identificação dos genótipos cagA e vacA em amostras de material fixado em formalina e incluído em parafina. RESULTADOS: A análise histológica permitiu a visualização direta do H. pylori em 85,7% dos casos, e o método de PCR para o gene urease C demonstrou a presença de DNA da bactéria em 95% dos casos. O gene cagA foi detectado em amostras de 23 pacientes (54,7%) com câncer gástrico. O alelo s1 do gene vacA foi identificado em amostras de 24 pacientes (57,1%) e o alelo m1, em amostras de 26 pacientes (61,9%). Os alelos s1 e m1 foram identificados simultaneamente em 24 pacientes (57,1%). O alelo s2 foi identificado em amostras de quatro pacientes (9,5%), e o alelo m2, em amostras de três pacientes (7,1%). A freqüência de infecção pelo Helicobacter pylori foi similar em ambos os tipos histológicos de câncer gástrico (intestinal e difuso). CONCLUSÕES: Os resultados confirmam a relevância dos genótipos patogênicos cagA e vacA do H. pylori para lesões orgânicas significativas tais como o câncer gástrico, sugerindo a participação dessa bactéria na cadeia de eventos da oncogênese gástrica.

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Ce travail a comme objectif analyser la structure et l'efficacité d'un système symbolique, qui est configuré à travers qui le philosophe Dufour (2000), à partir du linguiste Benveniste (1995) et du philosophe Lyotard (1998), dans la manutention et la sustentation des récits et d'histoires, appelle de trinité naturel des la langue. C'est sous cet appareil, inscrit à travers des pronomes « moi », « toi » et « lui » qui nous étudierons les suivantes questions: 1. comme s'il établit, synchronement, la mise à jour du mythe religieux Santa Menina présente dans la ville de Florânia, gêné dans le coeur broussard du Rio Grande do Norte? 2. qui manière, diachronement, les récits sur mentionné mythe s´il récupère? Le culte religieux à la Santa Menina est marqué discoursivement à travers d´un univers à facettes multiples qui se soutient à travers les voix de floranienses sur l'histoire d'une fille, dont le corps est trouvé intact et qui, sacralitée par la population, est connu comme la Santa Menina. Une histoire qui, notamment, avait/a répercussion et résonance, en participant, efficacement, des la réalité culturelle des la population. Théoriquement, notre travail est nourri par des savoirs arrivés, des la Linguistique, et des études sur la Mémoire et l'Histoire Verbale