Effect of ultrasonic ecxitation on the ultimate tensili strength of glass ionomer cements after different water storage times

The application of ultrasound waves with a conventional dental ultrasonic scaler on glass ionomer cements surface accelerated initial setting reaction and improved the mechanical properties. Objective: This study evaluated the ultimate tensile strength of glass ionomer cements after ultrasonic excitation and different water storage times. Material and method: Twelve specimens of each material (Fuji IX GP, Ketac Molar Easymix and Vitremer) were prepared, and six of each received a 30-second ultrasound application during initial setting of the cements. After storage of the 24 hours or 30 days, the specimens were sectioned into stick to microtensile testing and the mean ultimate tensile strength values were submitted to Welch’s ANOVA and Tamhane’s test. Result: The results showed that the Vitremer presented the highest mean tensile strength. The chemically set Fuji IX GP presented significantly higher mean tensile strength after 30 days than after 24 hours of storage (p < 0.05). At 24 hours, the ultrasonically set Fuji IX GP presented significantly higher mean tensile strength than their counterparts set under standard conditions (p < 0.05). Conclusion: Treatment with ultrasound increased the tensile strength of Fuji IX GP in the early period of maturation.

Surface roughness and hardness of yttria stabilized zirconia (Y-TZP) after 10 years of simulated brushing

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Abordagens estatísticas em testes de resistência de união entre dentina bovina, sistema adesivo e resina composta

Pós-graduação em Odontologia Restauradora - ICT

Adesivos multi-uso-avaliação da resistência adesiva a dentina frente a teste de cisalhamento, estereomicroscopia e microscopia eletrônica de varredura

Recent bonding systems have been advocated as multi-purpose bonding agents. The aim of this study was to determine if some of these bonding systems could be associated to composite resins from different manufacturers. This investigation was conducted to test lhe shear bond strength of three bonding systems: Scotchbond Multi-Purpose (3M Dental Products), Optibond Light Cure (Kerr) and Optibond Dual Cure (Kerr), when each of them was associated to lhe composite resins: Z1 00 (3M Dental Products), Prisma - APH (Dentsply) and Herculite XRV (Kerr). Seventy-two flat dentin bonding sites were prepared to 600 grit on human premolars mounted using acrilic resins. The teeth were assigned at random to 9 groups of 8 samples each. A split die with a 3mm diameter was placed over lhe surface of lhe dentin treated with one of lhe adhesive systems, and lhe selected composite resin was inserted and light cured. The split mold was removed and all samples were termocycled and stored in 37ºC water for 24 hours before testing. Shear bond strength was determined using an lnstron Universal testing machine. Some failures were examined under lhe S.E.M. Data was analysed by one-way analysis of variance, that demonstrated a significant difference (p<0,05) in the mean shear bond strength among Optibond Light Cure (15,446 MPa), Scotchbond Multi-Purpose (13,339 MPa) and Optibond Dual Cure (10,019 MPa). These values did not depend on the composite resin used. The association between bonding system/composite resin was statistycally significant (p<0,05) and the best results were obtained when the composite resins Z100 and Herculite were used with the adhesive system Optibond Light Cure, and when the composite resin APH was used with the adhesive system Scotchbond Multi-Purpose

Avaliação da erosão hídrica e transporte de sedimentos através do modelo hidrossedimentológico SWAT (Soil and Water Assessment Tool)

Pós-graduação em Geociências e Meio Ambiente - IGCE

Vulnerabilidade ambiental dos recursos hídricos interceptados por rodovias na bacia do rio Uberaba

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da sensibilidade de organismos aquáticos e terrestres ao triclopyr

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Estanho em amostras ambientais por espectrometria de fluorescência atômica (AFS)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Diferentes métodos de tratamento de superfície de um novo material nano-cerâmico/resina (Lava™ Ultimate): estudo in vitro da resistência adesiva

Dissertação para obtenção do grau de Mestre no Instituto Superior de Ciências da Saúde Egas Moniz

Estudo comparativo de diferentes sistemas de injeção de vapor aplicados à remediação de solos contaminados por diesel

Among the potentially polluting economic activities that compromise the quality of soil and groundwater stations are fuel dealers. Leakage of oil derived fuels in underground tanks or activities improperly with these pollutants can contaminate large areas, causing serious environmental and toxicological problems. The number of gas stations grew haphazardly, without any kind of control, thus the environmental impacts generated by these enterprises grew causing pollution of soil and groundwater. Surfactants using various techniques have been proposed to remedy this kind of contamination. This study presents innovation as the application of different systems containing surfactant in the vapor phase and compares their diesel removal efficiencies of soil containing this contaminant. For this, a system that contains seven injection wells the following vaporized solutions: water, surfactant solution, microemulsion and nanoemulsion, The surfactants used were saponified coconut oil (OCS), in aqueous solution and an ethoxylated alcohol UNTL-90: aqueous solution , and nanoemulsion and microemulsion systems. Among the systems investigated, the nanoemulsion showed the highest efficiency, achieving 88% removal of residual phase diesel, the most ecologically and technically feasible by a system with lower content of active matter

Estimativa da poluição emitida pelos ônibus das linhas troncais da cidade de Uberlândia, MG

The transport of people and goods contributes to the deterioration of the environment in urban areas because of the generation of pollution, such as, air, noise, soil, water or visual degradation. The heavy vehicles that use diesel as fuel are mainly responsible for the emission of nitrogen oxides (NOx) and particulate matter (PM), contributing to participation of the transport sector in air pollution. In addition, there is emission of Greenhouse Gas (GHG) whose main component is carbon dioxide (CO2). In most major cities, public transportation is often considered as a less polluting alternative compared to the private vehicle, in view of the potential to reduce, per passenger, the emissions of GHG and air pollutants. The study area was the city of Uberlândia and the objects of study were the trunk lines of the Sistema Integrado de Transporte (SIT). The emissions of NOx, PM and CO2 were estimated through the bottom-up approach which used the route of each bus line and also fuel consumption obtained through simulation from the TSIS software. The software has some result limitations, there are no report about the emission of pollutants by bus, and it is not able to change specifications for the fuel used by the fleet. The results obtained through calculations of pollutants and GHG emission by the bottom-up approach show that the emission is higher when using fuel comsuption obtained in simulation than using distance. For the results considering fuel and distance there was a reduction in emissions comparing ethanol and diesel.

La ruina como proceso: Robert Overby, Gordon Matta-Clark, Francesca Woodman y su legado

Me gustaría comenzar por agradecer a mi director Josu Larrañaga Altuna no solo su asistencia, guía y soporte para completar esta tesis, sino también el profundo respeto mostrado a la hora de plantear su ejecución en simbiosis con mi paulatino desarrollo vital como artista. Estoy en deuda con mi tutor en Estados Unidos, Leo Costello, por la generosidad mostrada al acogerme durante dos años como investigadora invitada en el Departamento de Historia del Arte de Rice University en Houston, durante los cuales iluminó algunos de los temas que han sido fundamentales para establecer las raíces históricas de la presente investigación. El estímulo y la calurosa acogida ofrecidos por la académica Fabiola López- Duran, Geoff Winnngahan y Annick Dekiouk que hicieron de Houston mi casa, integrándome en ese mundo donde los tejidos artísticos profesionales y académicos se entrelazan ha sido invaluable, así como la beca otorgada por la comisión Fulbright de España y la aceptación en el International Studio and Curatorial Program de Nueva York (ISCP) quienes hicieron posible la aventura americana. Gracias a esta, descubrí como una revelación a Robert Overby, esencial para el rumbo que tomó posteriormente la investigación. José Luis Corazón Ardura y Elisabeth Cummins Muñoz me aportaron el despertar a la conciencia de palabra justa sin renunciar a la esencia poética. Espero que esta tesis refleje las inestimables aportaciones que recibí de cada uno de ellos. Por otra parte me gustaría agradecer a mis galeristas Kerry Inman y Pilar Serra su apoyo a la hora de compatibilizar la vida académica con la artística. A mi hija Mariana por ofrecerme la maravillosa experiencia de descubrir paulatinamente el mundo juntas a través del lenguaje y sus diferentes idiomas. Y finalmente, mi más profundo reconocimiento a mi marido Alexandre, por creer en mí ciegamente, desde el principio y por encima de todas las cosas, mostrando su apoyo incondicional y constante en el tiempo. Porque su extraordinario valor me ha permitido seguir mis sueños y sobre todo por ofrecerme todas esas vidas posibles que no había osado soñar...

Indicadores energéticos: instrumentos de apoio ao desenvolvimento sustentável

Energy indicators are tools to support decision-making on energy. The growing debate on sustainable development, contributed to the energy indicators began to incorporate, besides the traditional economic, social and environmental information. Therefore, taking sustainable development into account, it is important to know contributions and limitations of these tools. The overall goal of this study is to analyze the contributions and limitations of the energy indicators as assets to support sustainable development.This study can be classified as descriptive because it relies on bibliographical and documental material. As a result of documental analysis, 55 energy indicators for sustainable development (EISD) were selected. The selection took place by identification of those indicators through the institutions International Atomic Energy Agency (IAEA), Helio International and World Energy Council (WEC), among 19 institutions involved in research on energy identified in the survey. The study stresses that most of the selected indicators focuses on the economic dimension, 19 EISDs (34.54%), followed by 10 EISDs (18.18%) focused on the environmental dimension, 9 EISDs (16.36%) focused on the social issues, 7 EISDs (12.45%) are classified as resilience, 4 EISDs (7.27%) is about governance, 3 EISDs (5.45%) focused on vulnerability and 3 EISDs (5.45%) is about policy. Despite the inclusion of indicators associated with other dimensions than economy, information provided by those indicators emerges as their own limitation. Because, recently, indicators’ information were used to promote sustainable development as well as the opposite. Additionally, the study identified EISDs whose components were not specified. They may enable generation of information far from the real scenario, if components dissociated EISD would be taking into consideration or even the non-consideration of relevant components. Despite limitations, EISDs assisting decision-makers contributes to the pursuit of sustainable development. But they may be improved through information about environmental issues, such as emission of atmospheric pollutants, soil and water, resulting from energy sources, helps identifying which sources are more or less harmful for sustainable development. However, difficulty in collecting data, identifying the components for calculation of each indicator and even interpretation of this, as analyzed, may not only fail to contribute to sustainable development, as can delay taking corrective or preventive decisions.

Proteômica diferencial da Chromobacterium violaceum em resposta ao estresse oxidativo induzido por peróxido de hidrogênio

The β-proteobacterium Chromobacterium violaceum is a Gram-negative, free-living, saprophytic and opportunistic pathogen that inhabits tropical and subtropical ecosystems among them, in soil and water of the Amazon. It has great biotechnological potential, and because of this potential, its genome was completely sequenced in 2003. Genome analysis showed that this bacterium has several genes with functions related to the ability to survive under different kinds of environmental stresses. In order to understand the physiological response of C. violaceum under oxidative stress, we applied the tool of shotgun proteomics. Thus, colonies of C. violaceum ATCC 12472 were grown in the presence and absence of 8 mM H2O2 for two hours, total proteins were extracted from bacteria, subjected to SDS-PAGE, stained and hydrolysed. The tryptic peptides generated were subjected to a linear-liquid chromatography (LC) followed by mass spectrometer (LTQ-XL-Orbitrap) to obtain quantitative and qualitative data. A shotgun proteomics allows to compare directly in complex samples, differential expression of proteins and found that in C. Violaceum, 131 proteins are expressed exclusively in the control condition, 177 proteins began to be expressed under oxidative stress and 1175 proteins have expression in both conditions. The results showed that, under the condition of oxidative stress, this bacterium changes its metabolism by increasing the expression of proteins capable of combating oxidative stress and decreasing the expression of proteins related processes bacterial growth and catabolism (transcription, translation, carbon metabolism and fatty acids). A tool with of proteomics as an approach of integrative biology provided an overview of the metabolic pathways involved in the response of C. violaceum to oxidative stress, as well as significantly amplified understanding physiological response to environmental stress. Biochemical and "in silico" assays with the hypothetical ORF CV_0868 found that this is part of an operon. Phylogenetic analysis of superoxide dismutase, protein belonging to the operon also showed that the gene is duplicated in genome of C. violaceum and the second copy was acquired through a horizontal transfer event. Possibly, not only the SOD gene but also all genes comprising this operon were obtained in the same manner. It was concluded that C. violaceum has complex, efficient and versatile mechanisms in oxidative stress response

Contributo da agricultura de conservação na prevenção do encharcamento e dos riscos de halomorfização dos solos argilosos na cultura de milho na área de influência de Alqueva

This study aims to evaluate the contribution of no-till (SD) and cover crops (CC) in mitigating the risk of salinity / sodicity of the soil. We tested whether the increase of soil infiltration rate and the reduction of the direct evaporation, achieved with a high amount of residues on the soil surface from the CC followed by SD, would enable a smaller accumulation of salts during the summer and more leaching of salt during winter. The experiment The experiment included two tillage systems: no-till associated to a winter cover crop (SD / CC) and the conventional system (SC) (chisel and disc harrows), divided into two water regimes and two levels of water salinity (0.7 dS m-1 and 2.0 dS m-1), both with adsorption sodium ratio 3. Contrary to expectations CC showed a tendency to increase salt content in Fall-Winter period, due to the reduction of the fraction available to leaching, but showed advantages in reducing long term salt content due to the improved structure of the B horizon, because decreases the tendency to the reduction of the structure of this horizon, caused typically by the permanent high moisture content during.