3,590 research outputs found

    O Distrito Federal é um só? - a (re) construção do imaginário nas lentes do coletivo Ceicine

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    1º Congresso Internacional Epistemologias do Sul: perspectivas críticas - 7 a 9 de novembro de 2016, realizada pela Universidade Federal da Integração Latino-Americana (UNILA).Nossa pesquisa discute as resistências dos atores cotidianos/locais através da produção cinematográfica sobre Brasília e posteriormente de Ceilândia expandida e socializada em devido a utilização de instrumentos e aparelhos técnicos fruto de modernizações que respondem a lógica de atores hegemônicos, mas que no lugar são resignificadas com base na lógica da cultura popular

    Multiphase Mass Transfer in Iron and Steel Refining Processes

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    In the present chapter, a computational fluid dynamics (CFD) model for multiphase flow was developed, allowing the simulation of two different processes, the desulfurization of hot metal in a ladle mechanically agitated by an impeller (KR process) and the desulfurization of steel in a gas-agitated ladle. The model gives important information to characterize the fluid flow conditions, to define the velocity profiles of the phases involved, and to predict the evolution of the sulfur content during the desulfurization treatments. An expression for the rate of transfer of sulfur from the metal to the slag was proposed. This expression can be used in processes where sulfur is transferred from the metal to the slag phase. The predictions of the variations of sulfur content of the metal phase with time were validated based on experimental data obtained in a Brazilian industrial plant for steel desulfurization. After the validation, the model was used to simulate the effects of several parameters and to optimize the processes. Based on these simulations, it was possible to set up the best operational conditions to improve the productivity of sulfur removal in the primary and secondary metallurgy

    Towards Multi-robot Exploration: A Decentralized Strategy for UAV Forest Exploration

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    Efficient exploration strategies are vital in tasks such as search-and-rescue missions and disaster surveying. Unmanned Aerial Vehicles (UAVs) have become particularly popular in such applications, promising to cover large areas at high speeds. Moreover, with the increasing maturity of onboard UAV perception, research focus has been shifting toward higher-level reasoning for single- and multi-robot missions. However, autonomous navigation and exploration of previously unknown large spaces still constitutes an open challenge, especially when the environment is cluttered and exhibits large and frequent occlusions due to high obstacle density, as is the case of forests. Moreover, the problem of long-distance wireless communication in such scenes can become a limiting factor, especially when automating the navigation of a UAV swarm. In this spirit, this work proposes an exploration strategy that enables UAVs, both individually and in small swarms, to quickly explore complex scenes in a decentralized fashion. By providing the decision-making capabilities to each UAV to switch between different execution modes, the proposed strategy strikes a great balance between cautious exploration of yet completely unknown regions and more aggressive exploration of smaller areas of unknown space. This results in full coverage of forest areas of variable density, consistently faster than the state of the art. Demonstrating successful deployment with a single UAV as well as a swarm of up to three UAVs, this work sets out the basic principles for multi-root exploration of cluttered scenes, with up to 65% speed up in the single UAV case and 40% increase in explored area for the same mission time in multi-UAV setups

    Considerações estéticas e didáticas para o ensino de literatura: uma apropriação materialista histórico-dialética de João Cabral de Melo Neto

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    Is the poetry of João Cabral de Melo Neto with its place assured in the current educational programs about literature teaching? Departing since a radical criticism about the state of art in pedagogics, it is considered that no. The current tendency today tends to discard it along with other precious literary productions, within a larger process of emptying of scholar contents. Why the valorization of poetry requires a substantive, historical and critical pedagogy theory? And why is João Cabral’s poetry relevant for an emancipating and critical education perspective? In other words, this paper underlines the importance of Historical-critical Pedagogy for educators and scholars of João Cabral, by one way; and the importance of João Cabral for educators that assume such the PHC as other critical perspectives in education, by another way. To solve this problem, the paper analyses the poem “The River”, and discuss the “esthetic reflection theory”, by György Lukács, as well the Activity Theory, by A. Leontiev, considered opportune for the problem of the directive or non-directive way of the educational work and its needs. These are existing questions in the pith of the current pedagogic problematics. ¿La poesía de João Cabral de Melo Neto esta con su lugar garantizado en los programas educativos sobre enseñanza de literatura? Partindo desde uma crítica radical del estado de arte pedagógica, se considera que no. La tendencia vigente hoy tende a desharcerse de ella juntamente a otras producciones literárias preciosas, bajo um proceso más grande de vaciamento de contenidos escolares. ¿Por qué lá valorización de la poesía neesita uma teoría pedagógica sustantiva, historica y crítica?; ¿y por qué la poesía de Cabral es cara a una perspectiva educativa emancipadora y crítica? En otras palabras, el trabajo resalta la importancia de la Pedagogía Histórico-Crítica para los educadores y estudiosos de João Cabral, por um lado; y la importancia de João Cabral para los educadores que asumen tanto la PHC cuanto otras perspectivas críticas em educació. Para resolver ese problema, se analisa el poem a “El Río”, y se discute la “teoria del reflejo estetico”, de György Lukács, así como la contribuición de A. Leontiev para la Teoría de la Actividad, considerada oportuna para el problema del direccionamiento o del no-direccionamiento del proceso educativo y de sus necesidades, questiones existentes en el cerne de la atual problematización pedagógica.A poesia de João Cabral de Melo Neto está com seu lugar garantido nos atuais programas educacionais sobre ensino de literatura? Partindo de uma crítica radical do estado da arte pedagógica, considera-se que não. A tendência vigente hoje tende a descartá-lo juntamente com outras produções literárias preciosas, dentro de um processo maior de esvaziamento dos conteúdos escolares. Por que a valorização da poesia necessita de uma teoria pedagógica substantiva, histórica e crítica; e por que a poesia de Cabral é relevante para uma perspectiva educativa emancipadora e crítica? Em outras palavras, o trabalho ressalta a importância da Pedagogia Histórico-crítica para os educadores e estudiosos de João Cabral, por um lado; e a importância de João Cabral para os educadores que assumem tanto a PHC quanto outras perspectivas críticas em educação, por outro. Para resolver esse problema, analisa-se o poema “O Rio”, e discute-se a “teoria do reflexo estético”, de György Lukács, bem como a contribuição de A. Leontiev para a Teoria da Atividade, considerada oportuna para o problema do direcionamento ou não direcionamento do processo educativo e de suas necessidades, questões existentes no cerne da atual problematização pedagógica

    Avaliação económica preliminar da nanofiltração na remoção de cianotoxinas em águas naturais

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    Com este trabalho pretende-se quantificar os custos associados à implementação e exploração de um sistema de nanofiltração (NF) na Estação de Tratamento de Águas (ETA) de Alcantarilha da Águas do Algarve, S.A. com uma capacidade de operação de 259.000 m3/d e efectuar uma comparação com os custos do actual sistema de tratamento implementado. A quantificação dos custos actuais foi efectuada através de dados obtidos a partir das operações desenvolvidas na ETA de Alcantarilha, fornecidos pelas Águas do Algarve, S.A. relativos a 2008 e 2009. Os custos foram estimados para as diferentes etapas de tratamento. Os resultados revelaram um custo associado ao tratamento de água para consumo humano de cerca de 0,10 €/m3.ano, para o esquema de tratamento existente na ETA de Alcantarilha. Realizaram-se ensaios experimentais à escala laboratorial e piloto onde se avaliou e optimizou o sistema de NF na remoção de matéria orgânica natural e cianotoxinas para diferentes taxas de recuperação de água (TxR), com águas que abastecem a actual ETA de Alcantarilha. A partir dos resultados obtidos com o estudo à escala piloto, verificou-se que a NF tem capacidade de produzir água de elevada qualidade com concentrações de microcistina muito inferiores ao valor legislado (1 mg/L), e baixo teor em matéria orgânica natural e de anatoxina- a, e que esta deve operar a TxR de pelo menos 75%. Com base nos resultados experimentais e através de modelos já desenvolvidos a partir de dados obtidos em trabalhos anteriormente realizados, determinaram-se os custos associados ao sistema de NF. O custo total estimado de implementação e operação/manutenção foi de 0,21 €/m3.ano para o ano de 2025. Conclui-se que apesar da implementação da NF na ETA de Alcantarilha provoque um acréscimo do custo de tratamento face ao tratamento convencional, este poderá ser justificável face à qualidade da água obtida

    Food Quality and Nutritional Profile of Students from a Public School in Brazil

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    Feeding is directly related to nutritional status and alterations as obesity and malnutrition, affecting human body and increasing the risk of morbidity and mortality. This study aimed to evaluate the nutritional status of children and adolescents in a public school located in Uberaba MG Brazil by comparing macro and micronutrients on the school menu with PNAE (Brazilian government program) recommendations. A descriptive cross-sectional study including 547 individuals was carried out. Nutritional assessment was done based on anthropometric Z-score analysis. Only the food ingestion made at the school was considered, in order to verify if the meals offered by the school meet the percentage of nutrients recommended by PNAE. With regard to the nutritional status, there was a small proportion of students (0.18%) with low weight (-3 ? Z < -2). There was 15% prevalence of overweight (overweight, obesity, and severe obesity) among students. Menus composition revealed that macronutrients, fiber, and energy intake was lower than that recommended by PNAE for all age groups studied. The prevalence of a considerable number of overweight students is a warning for interventions to prevent obesity. A small percentage of students classified as low weight represents a nutritional transition trend in recent years

    A rapid small scale evaluation of ultrafiltration performance for surface water treatment at Alcantarilha’s WTW (Algarve, Portugal)

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    A rapid small scale evaluation of ultrafiltration (UF) performance with and without physicalchemical pre-treatment was performed to up-grade the conventional treatment used for drinking water production in Alcantarilha’s WTW, Algarve, Portugal. Direct UF and pre-ozonation/ coagulation/ flocculation/ sedimentation/ UF (O/C/F/S/UF) were evaluated using polysulphone membranes of different apparent molecular weight cut-off (MWCO) (15-47 kDa). The results indicated that (i) UF is an effective barrier against microorganisms, including virus larger than 80 nm; (ii) for surface waters with low to moderate SUVA values, direct UF performance is equivalent or better than the conventional treatment in terms of residual turbidity, while UV254nm and TOC residuals require the use of O/C/F/S/UF; (iii) the permeate quality improves with the membrane apparent MWCO decrease, especially for the direct UF, although the conventional treatment performance is never reached using UF; (iv) membrane fouling and adsorption phenomena are more severe in direct UF than in O/C/F/S/UF sequence (preozonation decreases the membrane foulants by decreasing their hydrophobicity) and these phenomena increase with the membrane hydraulic permeability and, particularly, with the membrane apparent MWCO

    Ultrafiltração directa de águas superficiais turvas na ETA de Alcantarilha

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    Efectuou-se a ultrafiltração (UF), à escala laboratorial, de águas bruta e decantada da ETA de Alcantarilha para avaliar se, para águas turvas, o ajuste de pH pode substituir o pré-tratamento convencional (pré-ozonização/clarificação) à UF, na produção de água para consumo humano. A água bruta (30-40NTU, UV254nm (indicador de substâncias húmicas) 0.30–0.32cm-1 e COT 2.78–8.02mgC/l) foi permeada a diferentes valores de pH: 4.13, 7.60 (pH natural da água) e 8.33. A água decantada (2.9–5.1NTU, UV254nm 0.03–0.05cm-1 e COT < 3.5mgC/l) foi permeada a 7.48 (pH natural da água). Os resultados mostram que o ajuste de pH aumenta o desempenho da UF directa de águas turvas: os fluxos da UF directa, particularmente a pH básico, aproximam-se dos fluxos de água decantada e a turvação residual da água é equivalente à da UF com pré-tratamento convencional. Relativamente à MON, por acção da pré-ozonização, a presente na água decantada tem um peso molecular inferior e é mais hidrofílica. Assim, a UF directa produz uma água com maior concentração em substâncias húmicas (apesar das rejeições serem maiores), enquanto que em termos de COT a qualidade da água ultrafiltrada a pH ácido é semelhante à produzida por UF de água decantada. Em conclusão, o ajuste de pH parece viabilizar a UF directa de águas superficiais turvas. O efeito do pH é justificado por alteração da carga e tamanho da MON e das interacção membrana – matéria colmatante

    The yeast Saccharomyces cerevisiae is sensitive to colorectal cancer routine treatment EGFR antibody Cetuximab

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    Cetuximab/Erbitux® (Merk Sereno), a drug used in routine treatment of colorectal cancer and other malignant pathologies, is a monoclonal antibody against the Epidermal Growth Factor Receptor (EGFR). A frequent problem affecting the clinical use of Cetuximab is the lack of effectiveness deriving from frequent mutations in K-ras (1-3). A set of mutations in K-ras gene, KRAS c.35G>A (G12D), KRAS c.38G>A (G13D) in exon 2, and KRAS c.183A>T (Q61H) in exon 3, all implicated in the development of colorectal cancer, have been recognized as impeding Cetuximab’s EGFR inhibitory action in human (1). Ras human genes have recognized counterparts in yeast, RAS1 and RAS2. The corresponding proteins belong to the PKA/cAMP MAPK pathway are involved in cell proliferation, in differentiation into hyphae and spores, in response to nitrogen starvation, and in carbon source regulation (4, 5). In opposition to Ras, yeasts do not have a recognized ortholog of EGFR. Nevertheless, yeast is sensitive to Imatinib, another drug that targets specifically EGFR in human cells (6). We generated recombinant yeast strains expressing human wild-type (wt) and mutated open reading frames (ORFs) of K-ras to use in the optimization of phenotypic tests appropriate for the assessment of cell sensitivity to Cetuximab. We observed that Saccharomyces cerevisiae, is sensitive to the treatment with this drug at identical concentration as human cell cultures. Moreover, the complementation of yeast deletions in RAS1 and/or RAS2 with wt or the above mentioned mutated forms of human K-RAS did not alter the response of the cells to the treatment. This suggests that the sensitivity of S. cerevisiae to Cetuximab is independent of the Ras/cAMP pathway. These results further indicate the existence of a paralog of EGFR protein in yeast cell surface. In view of these results, research focused on identifying the EGFR yeast counterpart, downstream effectors and target genes, and determining the correspondent Cetuximab/Erbitux® mode of action.Este trabalho é financiado por Fundos FEDER através do Programa Operacional Factores de Competitividade – COMPETE e por Fundos Nacionais através da FCT – Fundação para a Ciência e a Tecnologia no âmbito do projecto PEst-C/BIA/UI4050/201
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