Desempenho adesivo de sistemas de união à dentina aplicados in vivo e in vitro: efeito da pressão intrapulpar e profundidade dentinária

O objetivo do presente estudo foi investigar a influência da pressão intrapulpar e da profundidade dentinária sobre o desempenho adesivo de dois agentes de união à dentina, Single Bond (3M ESPE, St. Paul, MN, EUA) e Clearfil SE Bond (Kuraray, Tokyo, Japão), aplicados in vitro e in vivo. Quarenta e oito prémolares superiores hígidos foram selecionados e os pares pertencentes aos mesmos pacientes foram aleatoriamente distribuídos em 4 grupos experimentais de acordo com o sistema adesivo e a pressão intrapulpar, presente ou ausente. Dos dentes pertencentes ao mesmo par, um foi tratado in vivo e o outro in vitro. A ausência ou presença de pressão intra-pulpar foi determinada in vivo pelo uso de anestésicos locais com ou sem vasoconstritor, respectivamente. In vitro, os dentes foram mantidos sob pressão hidrostática de 15 cm de água por 24 horas. Cavidades de classe I foram preparadas e os sistemas adesivos aplicados de acordo com a recomendação dos fabricantes, seguidos da restauração incremental em resina composta. Para os dentes tratados in vitro, os mesmos procedimentos restauradores foram realizados após 6 meses de armazenagem em solução contendo timol 0,1%. Espécimes com área de secção transversal de 1 mm2 foram obtidos e submetidos ao ensaio mecânico de microtração. In vivo, ambos os sistemas adesivos apresentaram desempenho adesivo comparável, enquanto in vitro, o sistema Single Bond foi superior ao sistema Clearfil SE Bond. Esse último não foi influenciado por nenhuma das variáveis estabelecidas no estudo, ou seja, aplicação in vitro ou in vitro, presença de pressão intrapulpar e profundidade em dentina. O sistema Single Bond aplicado sob pressão intrapulpar positiva sofreu variação significante de resistência de união em função da profundidade da dentina, ou seja, em dentina profunda seu desempenho adesivo... (Resumo completo, clicar acesso eletrônico abaixo)

Estudo da propagação de trinca por fadiga sob carregamento de amplitude variável

For engineering projects that require high reliability levels, is often not enough know only physical and chemical material properties. It’s necessary understand the failure mode of these materials in operation to ensure security level in the project and establish more stringent criteria in the analysis of structural integrity. Due to this need, aircraft industry has been using aluminum alloys in their designs and projects. “Currently more than 70% of aircraft structures are built of high strength aluminum alloys among which stand out 7075-T6 and 2024-T3 alloys, which are considered basics for being used in the new alloys development.” (PASTOUKHOV & VOORWALD, 1995). Some years ago ALCOA develops Al 2524 alloy that has emerged as refinement of Al 2024 (Al, Cu. Mg) alloy, with purpose of improve fracture toughness and fatigue resistance on structural components. The present research addresses testing of fatigue crack propagation under variable amplitude loading for Al 2024 alloy, observing the interaction effects from application of overhead blocks and plastic zone at the crack tip and makes an analysis of fracture surface images

A influência das características morfométricas e de uso da terra na morfodinâmica: um estudo da alta bacia do Rio Itanhaém - Baixada Santista/SP

Diante do desenfreado uso da terra, gerando impactos muitas vezes irreversíveis, o planejamento ambiental insere-se como uma ferramenta atualmente necessária. Visto que é sob o relevo que se consolidam as atividades antrópicas, a cartografia do relevo surge como um importante instrumento, indicando setores cujas características naturais impõem limites ao uso da terra. Assim, o objetivo desta pesquisa é analisar as características geomorfológicas da alta bacia do Rio Itanhaém, com ênfase à questão morfográfica e morfométrica do relevo, avaliando também as modificações impostas a este em decorrência do uso da terra, contribuindo, portanto, com a gestão ambiental desta área. Para tanto, foram elaborados documentos cartográficos capazes de evidenciar as características do relevo que impõem limites ao uso antrópico, a saber: as cartas morfométricas (carta de declividade, carta de dissecação vertical, carta de dissecação horizontal e carta de energia do relevo), que são documentos que evidenciam a suscetibilidade potencial do relevo sob a influência da ação das águas e gravitacional; a carta geomorfológica (cenário de 1962), que possibilita a espacialização das formas do relevo, contribuindo para a análise da morfodinâmica; e as cartas de uso da terra (cenário de 1962 e 2000), que, em conjunto com os documentos já especificados, possibilitam a análise da influência da atuação antrópica sob o sistema relevo. De maneira geral, pôde-se detectar problemas na morfodinâmica da área de estudo, evidenciados pela presença de feições denudacionais localizadas, tais como sulcos erosivos, voçorocas, ravina e cicatrizes de escorregamentos, os quais vinculam-se ao potencial natural que o relevo da área de estudo possui ao desencadeamento de processos morfogenéticos; à dinamização de processos naturais pela atuação antrópica... (Resumo completo, clicar acesso eletrônico abaixo)

Avaliação do método de classificação baseada no objeto em imagens de alta resolução espacial aplicado para o monitoramento de faixa de dutos: estudo de caso no entorno da refinaria de Capuava em Mauá - SP

The metropolitan region of São Paulo is the most populous of the country, this happens because of its great importance in the national economy and the job opportunities that are offered to the population. These factors result in intense population growth and urban expansion, reaching some non-habitable places of the metropolis, as areas of pipelines, which are very important for the transportation of natural gas, oil and its derivatives. Before the population growth of the region, these sites were unoccupied, do not presenting problems for the population. However, with the disorderly occupation is generated great anthropogenic pressure on the pipeline stitches, causing risks to people who are around them. Therefore it is extremely important to monitor the strip of pipelines through products and techniques of remote sensing and geoprocessing, enabling, through high spatial resolution images, identification of objects or phenomena that occur on Earth's surface that can alter the functioning and safety of pipelines. Therefore, this study aims to monitor a stretch of the area of the pipeline mesh GASPAL/OSVAT and Capuava Refinery (RECAP), located on the outskirts of the metropolitan area of São Paulo in the city of Mauá, who suffer great human pressure, proving thus the techniques of remote sensing and geographic information system (GIS) as effective tools for monitoring phenomena occurred in urban areas of great complexity. The monitoring was done by object-based classification applied in orbital images Ikonos II and RapidEye, of high spatial resolution and, image processing, detection of objects, segmentation, classification and editing were developed through the eCognition and ArcGis softwares. To determine the statistical accuracy of the mapping of the land cover of the stretch of pipeline in Maua, the results were analyzed by error matrix... (Complete abstract click electronic access below)

Biotratamento de sacolas plásticas de supermercado

Supermarket plastic bags are produced by high density polyethylene (HDPE) and low density polyethylene (LDPE) resins. In Brazil, are produced annually around 150 plastic bags per capita. Disposed in landfills, the supermarket plastic bags prevent the passage of water by slowing the breakdown of biodegradable materials and hindering compaction of waste, according to their low degradability. This work investigated the biodegradation of PE bags containing additive oxo-biodegradable and bags without additives: buried in soil columns, exposed in a controlled environment and exposed to air. The analysis methods used to assess the changes brought in the bags with respect to microbial action and exposure time were weight loss, thickness measurement, infrared (FTIR), scanning electron microscopy (SEM) and contact angle. The results showed that the use of prodegradant agents such as oxobiodegradable additives in polyethylene bags, buried in soil for 270 days, was not efficient to accelerate the biodegradation by microorganisms. It seems that these additives have been more efficient to degrade the colored pigmentation of printed bags, under the influence of light and heat.

Pressão arterial em cães: uma revisão

The evaluation of blood pressure is an essential tool for veterinarian clinical practice and for monitoring anesthetized patients or patients in intensive care, because of its usefulness in diagnostics, treatment and monitoring of several diseases. Apart from the pathological factor, the blood pressure also suffers the influence of different variables, such as age, breed, gender, temperament (anxiety and stress especially during the treatment, “white coat syndrome”), disease state, physical activity and, with lower intensity, animal’s diet. One of the main indications of the evaluation of blood pressure is the observation of clinical changes resulting from hypertension in animals, which one is characterized by lesions in the nervous and cardiovascular systems, kidneys and eyes. Not least important, the evaluation of blood pressure is also essential in hypotensive states, which represent an imminent risk of death. The techniques used in measuring blood pressure correspond to invasive forms (direct) or non invasive (indirect), whose correlation has been the subject of study and improvement within the small animal clinic. Thus, the purpose of this review is emphasize the importance of measuring blood pressure within the veterinary clinic routine, studying the influence of variables associated or not with elevated blood pressure, comparing the different methods used to obtain the blood pressure

Variabilidade espacial dos atributos físicos e químicos em um gleissolo mecânico sob três áreas no município Arari - MA

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Avaliação da pressão liquórica em pacientes obstétricas submetidas à anestesia subaracnoidea que apresentaram cefaleia pós-punção dural

Pós-graduação em Anestesiologia - FMB

Avaliação da autozigosidade em vacas Nelore (Bos indicus) através de genótipos SNP de alta densidade

Pós-graduação em Medicina Veterinária - FCAV

Os efeitos da alta temperatura e do myleran (busulfan) na espermatogênese de Devario aequipinnatus (teleostei, cyprinidae)

Pós-graduação em Ciência e Tecnologia Animal - FEIS

Sistema adesivo universal: influência da técnica de condicionamento e da pressão pulpar com soro fetal bovino ou água deionizada na resistência de união à dentina humana

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos de práticas de descompactação do solo em área sob sistema plantio direto

Soil compaction is one of the limiting factors in areas subjected to direct seeding. The method used to break up the compacted layer should disturb the soil as little as possible, as well as maintain the ground cover. The aim of this study was to evaluate the influence of subsoiling, scarification and use of shaft-type furrowing mechanisms when sowing, on preserving the ground cover, water content and soil density, as well as the effects on maize yield in a dystroferic Red Nitosol, cultivated under a system of direct seeding for ten years. The experimental design was of randomised blocks, with eight soil management treatments: subsoiling to a depth of 0.40 m before sowing the winter crop, subsoiling to 0.40 m before sowing the maize, scarification to 0.30 m before the winter crop, scarification to 0.30 m before the maize, scarification to 0.20 m before the winter crop, scarification to 0.20 m before the maize, direct seeding of the maize with a shaft-type furrowing mechanism and direct seeding of the maize using a double disc furrower. There were four replications. Subsoiling and scarification influenced the preservation of the ground cover, soil density and water content immediately after sowing, but did not interfere in plant development or grain yield in the maize crop. The use of shaft-type furrowing mechanisms in the sowing operation had no effect on any of the parameters under study.

Prediction of soil shear strength in agricultural and natural environments of the Brazilian Cerrado

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Comparação termométrica entre preparos cavitários realizados com turbinas de alta-rotação e laser de Er:YAG

The aim of this study was to compare temperature increases produced by a well-known equipment, the high-speed handpieces, with a relatively new instrument, the Er:YAG laser (350 mJ/10 Hz). Thirty-five bovine mandibular incisors, which were reduced to an enamel/dentin thickness of 2,5 mm, were used. Cavity preparation was done till a depth of 2, 5 mm. A thermocouple was placed to read the temperature inside of the pulp chamber. Analysis was performed in these groups: I - high-speed handpiece without water-cooling (n=10); II - high-speed handpiece with water-cooling (n=10); III - Er:YAG laser without water-cooling (n=5); IV- Er:YAG laser with water-cooling (n=10) Group III had only 5 teeth because it was impossible to properly make the cavity preparations by the laser equipment without water cooling. The temperature increases were recorded in a computer linked to the thermocouples and the data of the groups I, II and IV were submitted to Dunn's multiple comparison test (p<0,05). The medium temperature increases were: 11,64ºC for group I, 0,96ºC for group II, 40,86ºC for group III and 2,9°C for group IV. There were no statistical differences between groups lI and IV, and these were different from group I. The cavity preparations made by the high-speed and the laser equipment generated very similar heat increases under water-cooling. The water-cooling is essential to avoid aggressive temperature increases, both when using the high-speed and the laser equipment, and with laser it is especially necessary for ablation of enamel