Avaliação laboratorial da resistência ao cisalhamento de discos de porcelana e de um polímero de vidro cimentados à dentina bovina com o emprego de cimentos adesivos

Pós-graduação em Odontologia Restauradora - ICT

Avaliação do desempenho das propriedades mecânicas de concretos self compacting elaborados com diferentes tipos de cimentos submetidos à cura térmica

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Desenhos sobre aprendizagem e não aprendizagem: a construção do conhecimento social sob o enfoque piagetiano

The article presents preliminary data of a survey that aimed to investigate the beliefs of children and adolescents about not learning. A total of 80 students, aged 6 to 16 years participated of the study. Among the participants, 20 are 6 years old, 20 are 9, 20 are 12 and 20 are 16 years old. As methodological tool, it was asked the participants to draw a person that learns and another one that doesn’t learn. Data was analyzed according to the Piagetian perspective for the construction of social knowledge. The main results indicate that a significant part of the participants tend to blame the students for the result of no learning. This indicates that students are able to consider the amplitude of different dimensions of social phenomena only partially. When considering the level of understanding of social reality, it was observed that, even at older ages, participants have a very basic notion of the social world.

Dilemas e hesitações da modernidade tardia e a emergência da sociedade de controle

The objective of this study is to emphasize the fundamental points of the theoretical discussion about late modernity. In the two last decades, authors like Giddens, Beck, Bauman, Sennett and Garland have emphasized the social, historical and theoretical characterization of modernity in the advanced occidental societies. This discussion, despite being indispensable, does not allow the comprehension of the problems of this new stage of occidental capitalism in terms of its technical dimension and social control. The article arguments in favor of the incorporation of analysis of Michel Foucault’s power and stresses its present reality and potential. This author renewed the theoretical possibilities of the human sciences as he criticized a naturalized view of History and historical events. The influence of his works, an analysis of modernity, may be observed in the debate around the crisis of modernity and the emerging society of control. At the same time, his work helps us understand the main dilemmas and hesitations of contemporary societies.

Um Método para a Utilização de Ontologias na Indexação Automática

The indexing process aims to represent synthetically the informational content of documents by a set of terms whose meanings indicate the themes or subjects treated by them. With the emergence of the Web, research in automatic indexing received major boost with the necessity of retrieving documents from this huge collection. The traditional indexing languages, used to translate the thematic content of documents in standardized terms, always proved efficient in manual indexing. Ontologies open new perspectives for research in automatic indexing, offering a computer-process able language restricted to a particular domain. The use of ontologies in the automatic indexing process allows using a specific domain language and a logical and conceptual framework to make inferences, and whose relations allow an expansion of the terms extracted directly from the text of the document. This paper presents techniques for the construction and use of ontologies in the automatic indexing process. We conclude that the use of ontologies in the indexing process allows to add not only new feature to the indexing process, but also allows us to think in new and advanced features in an information retrieval system.

As relações entre a construção da abstração reflexionante e o conhecimento social: um estudo psicogenético

This article aims to investigate the construction of reflective abstraction and relate it to the construction of social knowledge. So, two methodological tools were applied to 60 students aged between ten and 16 years: a) evidence of the construction of surfaces and perimeters b) clinical interview about the origins of Earth and life. The main results show that participants were presented at more elementary levels of constuction of reflective abstraction and contruction of social knowledge despite the advanced age and schooling. Statistical analysis revealed a highly significant relationship between the constuction of abstraction and social knowledge.

Caracterização de argilas usadas para produção de cerâmica vermelha e estudo das alterações nas suas propriedades pela adição de resíduos

Neste trabalho são apresentados os resultados de caracterização das principais argilas usadas pela indústria cerâmica vermelha regional e, também, de alguns resíduos sólidos produzidos na região de Presidente Prudente - SP. Os resultados da incorporação destes resíduos em massas cerâmicas são avaliados através do estudo de suas propriedades tecnológicas. Para a caracterização dos materiais foram utilizadas as seguintes técnicas: análise textural (concentração das frações areia, silte e argila), difratometria de raios X e análise térmica. As propriedades tecnológicas de corpos de prova cerâmicos foram avaliadas através dos seguintes parâmetros: retração linear (RL), perda de massa ao fogo (PF), massa específica aparente (MEA), porosidade aparente (PA), absorção de água (AA) e resistência mecânica à flexão (RMF). Corpos de prova, com diferentes concentrações de resíduos, foram prensados (prensa uniaxial manual) e queimados em temperaturas que variaram de 800 a 1200 oC, usando um forno tipo mufla com controle de temperatura. As argilas sedimentares foram coletadas nas margens do rio Paraná e em áreas de várzea, próximas as cerâmicas. As amostras estudadas, coletadas nos depósitos das cerâmicas, são usadas para produção de tijolos maciços, blocos furados e telhas. Quatro tipos diferentes de resíduos foram estudados: (1) lodo de estação de tratamento de água ETA, (2) torta de filtro de indústria de re-refino de óleo lubrificante, (3) pó de vidro (soda-cal) de garrafa tipo long neck descartável, e (4) cinza de bagaço de cana. Estes resíduos foram incorporados em massas cerâmicas coletadas nas indústrias... (Resumo completo, clicar acesso eletrônico abaixo)

Obtenção e caracterização de suporte de regeneração óssea de dióxido de titânio

Due to complications caused by metallic implants in the replacement of bone tissue, the biological application of ceramics raised and became a viable alternative. The titania has the ability to promote bone tissue regeneration based on its structure, mechanical and biologically properties compatibility. The present work aims at obtaining and characterization of Titania (TiO2) porous ceramics produced by the polymeric sponge method (replica method). Polyurethane sponge with 10 ppi and 15 ppi (pores per linear inch) were used. The process differentiation is the air blower used to remove excess slurry. The ceramics sponges were dried in an oven, then pre-sintered at 1000 o C and sintered at 1450 o C. The effect of direct sintering at 1450 o C was also assessed. The percentage of solids used to prepare the slurry was 40 to 45% by weight. To increase the surface porosity of the sponge, 20% of starch was added. There was difficulty on controlling the thickness of the slurry layers on the sponge which resulted in the variation of samples mechanical resistance. Despite this, the results obtained are quite promising for the proposed use, indicating that it is possible to obtain titania sponges with an apparent porosity of around 60%, a bulk density ranging from 40 to 47% and a compressive strength resistance – that with better control of layers depositions – can vary from 1 to 4 MPa

Vitrocerâmicas porosas via conformação e consolidação com amidos

The search for new methods of manufacture of glass-ceramics with controlled porosity and permeability is interesting of the industrial and commercial point of view, and a challenge of great complexity. Porous glass-ceramics produced by sintering and crystallization of glasses can find applications, for example, as filters, materials with bactericidal properties, bio-implants, as catalytic and enzymes supports, among others. An alternative and low cost method of ceramic manufacture reaching different levels of porosity, for diverse purposes, is the conformation assisted by addition of starch, known as consolidation with starch. The objective of this project is to study the process of conformation with starch for making porous glass-ceramics from a commercial glass in the system Na2O-CaO-SiO2, whose kinetics of sintering by viscous flow and surface crystallization are known. The method of conformation with starches is innovative for glass-ceramics and its development opens the way for obtaining a new class of materials. We found a possible route for the production of porous compacts of glass particles, from the powder preparation to the removal of starch. It was observed that a glass powder obtained by dry milling in a ball mill with alumina balls for 24 h, afterwards mixed with water in an eccentric ball mill for 2 h, without the addition of a deflocculant, and subsequently mixed with starch also in an eccentric ball mill for 5 min resulted in slurries stable against sedimentation

Sobre as considerações de uma concepção de um projeto de um forno cerâmico

The current competitiveness of the market has generated the need to minimize the cost of production companies in any field of activity, aimed at reducing the cost of production, the cost of purchasing and manufacturing processes interruption of manufacturing processes for possible maintenance. In this sense, companies are seeking methods to improve and streamline their production line. In ceramics industries, cooking the pieces is the portion of the production process that influences the total costs. The oven construction and maintenance represent a large portion embedded in the cost of the final ceramic product. The proposal for a type of oven for baking the parts that takes into account a better burning process, knowledge of the causes of disease and cost analysis of purchasing both of the constituent materials and labor for its construction, can be significant importance to the composition of final product costs or time analysis of ROI. It is proposed a streamlined design of an oven that takes into account the positive characteristics of the furnaces already built and that the experience has endorsed, and also others that are added at the end, lead to a reduction in production cost, the cost income and the number of pathologies arising from wear of the furnace along the lifespan. Therefore, according to the experiences gained over the years in the construction of furnaces and experience of manufacturing of ceramic, it is proposed a project that has an oven improvement over those now being built and that include, among other topics, economy in fuel burning, streamlining the building process

Proposta para melhoria da qualidade dos produtos cerâmicos e de criação de um polo cerâmico artesanal na cidade de Indiana - SP

This work presents a proposal to create a Polo Ceramic Craft in the town of Indiana - SP, through the potter’s organization in a cooperative that will coordinate activities to add value to ceramic pieces. To achieve this, two things are essential: improving the ceramic body and improve the properties of the ceramic material. For the first action it’s necessary to create a Central Mass Production of Ceramics, to provide raw materials and homogeneous composition that results in differentiated ceramic after burning process (sintering). To this end, we propose the incorporation of additives (which act as fluxes) to the clay material. These additives can be mineral such as feldspar and nefelinas or leavings, such as glass powder obtained from disposable containers. For the second action is necessary to acquire an oven, electric or gas, it reaches higher temperatures (around 1200 ° C). The presence of the additive and burning at higher temperatures will enable better production of sintered ceramic material with less porosity and water absorption and higher mechanical strength, and pieces vitrified and glazed, allowing them to assign a higher value. For the production of these materials (thinner walls) requires a smaller volume of clayey raw materials. Besides benefiting the ceramic pieces, the proposed changes reduce the environmental impact caused by burning wood, since it will be replaced by natural gas (or electricity), and even will reduce the disposal of glass containers in the environment by recycling and incorporating this material in the clay. From a social standpoint, the cooperative is crucial to the viability of the proposed project, to coordinate activities and commercial production, which will result in better wages and profits for companies and consequently for the city and its population

Síndrome urêmica em cães com doença renal crônica

Uremic syndrome, arising from kidney malfunction, consists of a set of systemic changes caused by the accumulation of toxic substances to the body. Since, with the advance of medicine, the animals lived more reaching advanced age and entering thus on track of senility, chronic renal disease, became a common complaint in the routine of the ambulatory. This high rate of morbidity generates an increased need for clarification of pathophysiology involved in this disease. The components of the uremic syndrome include water and sodium imbalance, anemia, intolerance to carbohydrate, neurological disorders, disorders of the gastrointestinal tract, osteoarthritis, immunological incompetence and metabolic acidosis. The clinical manifestations occur in isolation or in combination. In most cases canines patients are subject to an assessment when the kidney disease has evolved to the final stage with uremic syndrome and installed already, under these conditions, the prognosis is reserved

Vitrocerâmicas para blindagens balísticas

The use of ceramic materials in ballistic armor is considerable. Such materials can be very harder and lighter than metallic materials commonly used and it presents advantages to replace metallic materials when necessary toughness can be achieved. However, as SiC and Al2O3 ceramic, traditionally used for shielding, still have high manufacturing cost or low density do not have enough to shield applications such as aircraft. An alternative is the glass-ceramics, ceramics obtained by controlled crystallization of glasses, whose properties can be adjusted by choosing the chemical composition of glass, heat treatment of crystallization and special treatments such as ion exchange on the surface, resulting in increased mechanical strength . The objective of this project is to study the kinetics of crystallization of a glass composition based on cordierite (2MgO.2Al2O3.5SiO2), low density and high hardness, for the manufacture of glass-ceramics for ballistic tests. Shown in this report are results of heat treatment of crystallization and characterization by thermal analysis (DSC) glass obtained previously, indicating uneven distribution of crystals, and drying, weighing, mixing of raw materials and a new fusion of glass, the same composition

Scout no futsal: o que os números mostram sobre o jogo

Nos últimos tempos o futsal tem se desenvolvido muito rapidamente, modificando seu caráter amador e aumentando o número de participantes e de país que o praticam. Essas mudanças têm causado melhoras nas ações técnicas e táticas dos jogadores, além de aumento na rapidez do raciocínio para a tomada de decisão, além da forma física (necessidade de uma capacidade aeróbica e de uma massa muscular desenvolvidas para a melhora do desempenho em quadra). Um dos responsáveis pelo desenvolvimento do futsal foram os avanços na tecnologia que através de ferramentas específicas facilitam e auxiliam na evolução da equipe no decorrer dos treinamentos e jogos. Desta forma, as equipes conseguem controlar os aspectos técnicos, táticos, físicos e psicológicos que ocorrem com a equipe, podendo obter dados quantitativos e qualitativos que ajudam a alcançar melhor performance dos atletas e da equipe. Um exemplo destas ferramentas é o “scout”, o qual se mostra um instrumento viável para uma avaliação técnica e tática de uma equipe. Através desta ferramenta pode-se avaliar detalhes importantes do jogo como o número de finalizações (eficiência do ataque), local de finalização, número de desarmes, passes certos e errados, tanto da sua equipe como também da equipe adversária. Com isso, com o auxilio do “scout” independentemente da tecnologia que se utilize, mais avançadas como softwares específicos ou menos sofisticadas como planilhas de anotações, consegue-se além de realizar uma avaliação individual da condição técnica do atleta também analisar os sistemas de defesa e ataque de uma equipe.Assim, o objetivo deste estudo foi de verificar e comparar a relação de acerto e erro das ações de passe, desarme e finalização apresentado pelas equipes vencedoras e as perdedoras de partidas de futsal, vislumbrando...(Resumo completo, clicar acesso eletrônico abaixo)

Efeito de diferentes espessuras, técnicas de aplicação e protocolos de resfriamento na resistência à fratura da cerâmica de cobertura aplicada sobre infraestrutura de y-tzp

Pós-graduação em Odontologia Restauradora - ICT