Avaliação do selamento de ápices radiculares retrobturados ou recobertos com diferentes materiais mediante infiltração marginal por corante e análise da interface em microscopia eletrônica de varredura

The purpose of this study was to evaluate the apical sealing ability and the marginal adaptation of five dental materials used in retrofillings or applied to the bevelled root surface. One hundred and forty extracted single rooted human teeth were used, divided into seven groups of twenty each. ln the first, second, third and fourth groups, the teeth were apicoectomized, submitted to cavity preparations and retrofilled with one of the following materiais: zinc free silver amalgam, a dentin bonding system plus composite resin, a glass ionomer cement ora compomer. In the fifth, sixth and seventh groups, the teeth were apicoectomized and capped on the bevelled root surface with one of the following materiais: a dentin bonding system plus composite resin, a glass ionomer cement or a compomer. Two specimens of each experimental group were evaluated for the marginal adaptation using scanning electron microscopy. The remaining 126 specimens were immersed in 2% methylene blue dye, stored for one week at 37ºC and the infiltration was evaluated with a stereomicroscope. The results showed that the glass ionomer cement presented the lowest values of marginal infiltration when used as retrofilling material, with a significant statistical difference when compared with the others tested materials. When used as apical capping, the glass ionomer cement and the compomer were equivalent and significantly better than the dentin bonding system plus composite resin. Using scanning electron microscopy, all the materials showed some slight adjustment problem. ln the retrofilling, the smallest marginal gaps were observed with the compomer and the dentin bonding system plus composite resin, while the largest were observed with the glass ionomer cement and zinc free silver amalgam. ln the apical capping, the smallest marginal gaps were observed with the compomer and the dentin bonding system plus composite resin and ...

Análise da efetividade de polimerização, adaptação marginal e interna de restaurações Classe II de resinas compostas de inserção em bloco utilizando diferentes matrizes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

The importance of biotic interactions and local adaptation for plant response to environmental changes: field evidence along an elevational gradient

Predicting the response of species to environmental changes is a great and on-going challenge for ecologists, and this requires a more in-depth understanding of the importance of biotic interactions and the population structuration in the landscape. Using a reciprocal transplantation experiment, we tested the response of five species to an elevational gradient. This was combined to a neighbour removal treatment to test the importance of local adaptation and biotic interactions. The trait studied was performance measured as survival and biomass. Species response varied along the elevational gradient, but with no consistent pattern. Performance of species was influenced by environmental conditions occurring locally at each site, as well as by positive or negative effects of the surrounding vegetation. Indeed, we observed a shift from competition for biomass to facilitation for survival as a response to the increase in environmental stress occurring in the different sites. Unlike previous studies pointing out an increase of stress along the elevation gradient, our results supported a stress gradient related to water availability, which was not strictly parallel to the elevational gradient. For three of our species, we observed a greater biomass production for the population coming from the site where the species was dominant (central population) compared to population sampled at the limit of the distribution (marginal population). Nevertheless, we did not observe any pattern of local adaptation that could indicate adaptation of populations to a particular habitat. Altogether, our results highlighted the great ability of plant species to cope with environmental changes, with no local adaptation and great variability in response to local conditions. Our study confirms the importance of taking into account biotic interactions and population structure occurring at local scale in the prediction of communities’ responses to global environmental changes.

Patterns of psychological adaptation to divorce

Despite the increase in divorces after a long relationship, this trend remains a neglected research topic. The present contribution seeks to identify patterns of psychological adaptation to divorce after a long-term marriage. Data from a questionnaire study with 308 persons aged 45–65 years, who divorced after having been married for an average of 25 years, are presented. Exploratory latent profile analysis with various well-being outcomes revealed five groups: one with average adapted, one with resilients, and three small groups with seriously affected individuals. Discriminant variables between the groups were personality, time since separation, a new relationship, and financial situation. Age, gender, and length of marriage played a marginal role; satisfaction with the former marriage and initiator status were not relevant.

Exploring strategic farming choices to respond to mitigation and adaptation to climate change

Las alteraciones del sistema climático debido al aumento de concentraciones de gases de efecto invernadero (GEI) en la atmósfera, tendrán implicaciones importantes para la agricultura, el medio ambiente y la sociedad. La agricultura es una fuente importante de emisiones de gases de efecto invernadero (globalmente contribuye al 12% del total de GEI), y al mismo tiempo puede ser parte de la solución para mitigar las emisiones y adaptarse al cambio climático. Las acciones frente al desafío del cambio climático deben priorizar estrategias de adaptación y mitigación en la agricultura dentro de la agenda para el desarrollo de políticas. La agricultura es por tanto crucial para la conservación y el uso sostenible de los recursos naturales, que ya están sometidos a impactos del cambio climático, al mismo tiempo que debe suministrar alimentos para una población creciente. Por tanto, es necesaria una coordinación entre las actuales estrategias de política climática y agrícola. El concepto de agricultura climáticamente inteligente ha surgido para integrar todos estos servicios de la producción agraria. Al evaluar opciones para reducir las amenazas del cambio climático para la agricultura y el medio ambiente, surgen dos preguntas de investigación: • ¿Qué información es necesaria para definir prácticas agrarias inteligentes? • ¿Qué factores influyen en la implementación de las prácticas agrarias inteligentes? Esta Tesis trata de proporcionar información relevante sobre estas cuestiones generales con el fin de apoyar el desarrollo de la política climática. Se centra en sistemas agrícolas Mediterráneos. Esta Tesis integra diferentes métodos y herramientas para evaluar las alternativas de gestión agrícola y políticas con potencial para responder a las necesidades de mitigación y adaptación al cambio climático. La investigación incluye enfoques cuantitativos y cualitativos e integra variables agronómicas, de clima y socioeconómicas a escala local y regional. La investigación aporta una recopilación de datos sobre evidencia experimental existente, y un estudio integrado sobre el comportamiento de los agricultores y las posibles alternativas de cambio (por ejemplo, la tecnología, la gestión agrícola y la política climática). Los casos de estudio de esta Tesis - el humedal de Doñana (S España) y la región de Aragón (NE España) - permiten ilustrar dos sistemas Mediterráneos representativos, donde el uso intensivo de la agricultura y las condiciones semiáridas son ya una preocupación. Por este motivo, la adopción de estrategias de mitigación y adaptación puede desempeñar un papel muy importante a la hora de encontrar un equilibrio entre la equidad, la seguridad económica y el medio ambiente en los escenarios de cambio climático. La metodología multidisciplinar de esta tesis incluye una amplia gama de enfoques y métodos para la recopilación y el análisis de datos. La toma de datos se apoya en la revisión bibliográfica de evidencia experimental, bases de datos públicas nacionales e internacionales y datos primarios recopilados mediante entrevistas semi-estructuradas con los grupos de interés (administraciones públicas, responsables políticos, asesores agrícolas, científicos y agricultores) y encuestas con agricultores. Los métodos de análisis incluyen: meta-análisis, modelos de gestión de recursos hídricos (modelo WAAPA), análisis multicriterio para la toma de decisiones, métodos estadísticos (modelos de regresión logística y de Poisson) y herramientas para el desarrollo de políticas basadas en la ciencia. El meta-análisis identifica los umbrales críticos de temperatura que repercuten en el crecimiento y el desarrollo de los tres cultivos principales para la seguridad alimentaria (arroz, maíz y trigo). El modelo WAAPA evalúa el efecto del cambio climático en la gestión del agua para la agricultura de acuerdo a diferentes alternativas políticas y escenarios climáticos. El análisis multicriterio evalúa la viabilidad de las prácticas agrícolas de mitigación en dos escenarios climáticos de acuerdo a la percepción de diferentes expertos. Los métodos estadísticos analizan los determinantes y las barreras para la adopción de prácticas agrícolas de mitigación. Las herramientas para el desarrollo de políticas basadas en la ciencia muestran el potencial y el coste para reducir GEI mediante las prácticas agrícolas. En general, los resultados de esta Tesis proporcionan información sobre la adaptación y la mitigación del cambio climático a nivel de explotación para desarrollar una política climática más integrada y ayudar a los agricultores en la toma de decisiones. Los resultados muestran las temperaturas umbral y la respuesta del arroz, el maíz y el trigo a temperaturas extremas, siendo estos valores de gran utilidad para futuros estudios de impacto y adaptación. Los resultados obtenidos también aportan una serie de estrategias flexibles para la adaptación y la mitigación a escala local, proporcionando a su vez una mejor comprensión sobre las barreras y los incentivos para su adopción. La capacidad de mejorar la disponibilidad de agua y el potencial y el coste de reducción de GEI se han estimado para estas estrategias en los casos de estudio. Estos resultados podrían ayudar en el desarrollo de planes locales de adaptación y políticas regionales de mitigación, especialmente en las regiones Mediterráneas. ABSTRACT Alterations in the climatic system due to increased atmospheric concentrations of greenhouse gas emissions (GHG) are expected to have important implications for agriculture, the environment and society. Agriculture is an important source of GHG emissions (12 % of global anthropogenic GHG), but it is also part of the solution to mitigate emissions and to adapt to climate change. Responses to face the challenge of climate change should place agricultural adaptation and mitigation strategies at the heart of the climate change agenda. Agriculture is crucial for the conservation and sustainable use of natural resources, which already stand under pressure due to climate change impacts, increased population, pollution and fragmented and uncoordinated climate policy strategies. The concept of climate smart agriculture has emerged to encompass all these issues as a whole. When assessing choices aimed at reducing threats to agriculture and the environment under climate change, two research questions arise: • What information defines smart farming choices? • What drives the implementation of smart farming choices? This Thesis aims to provide information on these broad questions in order to support climate policy development focusing in some Mediterranean agricultural systems. This Thesis integrates methods and tools to evaluate potential farming and policy choices to respond to mitigation and adaptation to climate change. The assessment involves both quantitative and qualitative approaches and integrates agronomic, climate and socioeconomic variables at local and regional scale. The assessment includes the collection of data on previous experimental evidence, and the integration of farmer behaviour and policy choices (e.g., technology, agricultural management and climate policy). The case study areas -- the Doñana coastal wetland (S Spain) and the Aragón region (NE Spain) – illustrate two representative Mediterranean regions where the intensive use of agriculture and the semi-arid conditions are already a concern. Thus the adoption of mitigation and adaptation measures can play a significant role for reaching a balance among equity, economic security and the environment under climate change scenarios. The multidisciplinary methodology of this Thesis includes a wide range of approaches for collecting and analysing data. The data collection process include revision of existing experimental evidence, public databases and the contribution of primary data gathering by semi-structured interviews with relevant stakeholders (i.e., public administrations, policy makers, agricultural advisors, scientist and farmers among others) and surveys given to farmers. The analytical methods include meta-analysis, water availability models (WAAPA model), decision making analysis (MCA, multi-criteria analysis), statistical approaches (Logistic and Poisson regression models) and science-base policy tools (MACC, marginal abatement cost curves and SOC abatement wedges). The meta-analysis identifies the critical temperature thresholds which impact on the growth and development of three major crops (i.e., rice, maize and wheat). The WAAPA model assesses the effect of climate change for agricultural water management under different policy choices and climate scenarios. The multi-criteria analysis evaluates the feasibility of mitigation farming practices under two climate scenarios according to the expert views. The statistical approaches analyses the drivers and the barriers for the adoption of mitigation farming practices. The science-base policy tools illustrate the mitigation potential and cost effectiveness of the farming practices. Overall, the results of this Thesis provide information to adapt to, and mitigate of, climate change at farm level to support the development of a comprehensive climate policy and to assist farmers. The findings show the key temperature thresholds and response to extreme temperature effects for rice, maize and wheat, so such responses can be included into crop impact and adaptation models. A portfolio of flexible adaptation and mitigation choices at local scale are identified. The results also provide a better understanding of the stakeholders oppose or support to adopt the choices which could be used to incorporate in local adaptation plans and mitigation regional policy. The findings include estimations for the farming and policy choices on the capacity to improve water supply reliability, abatement potential and cost-effective in Mediterranean regions.

Global adaptation of spring bread and durum wheat lines near-isogenic for major reduced height genes

The effect of major dwarfing genes, Rht-B1 and Rht-D1, in bread (Triticum aestivum L.) and durum (Triticum turgidum L. var. durum) wheats varies with environment. Six reduced-height near-isogenic spring wheat lines, included in the International Adaptation Trial (IAT), were grown in 81 trials around the world. Of the 56 IAT trials yielding > 3 Mg ha(-1), the mean yield of semidwarfs was significantly greater than tails in 54% of trials; in the 27 trials yielding < 3 Mg ha-1, semidwarfs were superior in only 24%. Sixteen pairs of semidwarf-tall near-isolines were grown in six managed drought environment trials (DETs) in northwestern Mexico. In these trials, semidwarfs outyielded talls in all but the most droughted environment (2.5 Mg ha(-1)). The effect of the height alleles varied with genetic background and environment. For both yield and height, variance components for allele and environment by allele interaction were larger than those for genetic background and genetic background by environment. Pattern analysis showed that tall and semidwarf lines had similar adaptation to stressed environments (< 2.8 Mg ha(-1), low rainfall), while semidwarfs yielded more in less stressed environments (> 4.3 Mg ha(-1), high rainfall). The best adapted near-isogenic pair had a Kauz background, where the tall was only 16% taller than the dwarf. In the Kauz-derived pair, the semidwarf outyielded the tall in only 13% of trials with no differences in low yielding trials. This supports the idea that '' short talls '' may be useful in marginal environments (yield < 3 Mg ha(-1)).

Growth, uniformity, local responsiveness, and system-wide adaptation in multiunit franchising

Using the resource-based view framework, we investigate the link between multiunit franchising (MUF) and performance on four key challenges in franchise chain management: growth, uniformity, local responsiveness, and system-wide adaptation. Our findings support the assertion that system growth is positively related to MUF rate within a system, in particular in relation to geographic expansion. Interestingly, while uniformity does not seem to be related to MUF rate, we find marginal support for an inverted u-shaped relationship between system-wide adaptation and MUF rate. Furthermore, the data suggest that local responsiveness and MUF rate are related in a u-shaped function.

Avaliação da adaptação marginal de diferentes tipos de restaurações obtidas por CAD/CAM e métodos convencionais

The past few decades have brought many changes to the dental practice and the technology has become ready available. The result of a satisfactory rehabilitation treatment basically depends on the balance between biological and mechanical factors. The marginal adaptation of crowns and prosthetic structures is vital factor for long-term success. The development of CAD / CAM technology in the manufacture of dental prostheses revolutionized dentistry, this technology is capable of generating a virtual model from the direct digital scanning from the mouth, casts or impressions. It allows the planning and design of the structure in a computered software. The virtual projects are obtained with high precision and a significant reduction in clinical and laboratory time. Thus, the present study (Chapters 1, 2 and 3) computed microtomography was used to evaluate, different materials, different CAD/CAM systems, different ways of obtaining virtual model (with direct or indirect scanning), and in addition, also aims to evaluate the influence of cementing agent in the final adaptation of crowns and copings obtained by CAD / CAM. Furthermore, this study (Chapter 4, 5 and 6) also aims to evaluate significant differences in vertical and horizontal misfits in abutment-free frameworks on external hexagon implants (HE) using full castable UCLAs, castable UCLAs with cobalt-chromium pre-machined bases and obtained by CAD / CAM with CoCr or Zirconia by different scanning and milling systems. For this, the scanning electron microscopy and interferometry were used. It was concluded that the CAD / CAM technology is capable to produce restorations, copings and screw-retained implant-supported frameworks in different materials and systems offering satisfactory results of marginal accuracy, with significative reduction in clinical and laboratory time.

Avaliação in vitro da adaptação marginal e interna de coroas de cerâmica e resina composta fabricadas com o sistema CAD/CAM utilizando duas câmeras intraorais de moldagem digital

Dissertação (mestrado)—Universidade de Brasília, Faculdade de Ciências da Saúde, Programa de Pós-Graduação em Ciências da Saúde, 2015.