842 resultados para Complexidade estrutural
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Nowadays, composite resins are the direct restorative materials more important in dental clinical performance, due to their versatility and aesthetic excellence. Bis-GMA (2,2-bis[4(2-hydroxy-3-metacryloxypropoxy)phenil]propane) is the base monomer more frequently used in restorative composite resins. However, this monomer presents some disadvantages, such as high viscosity and two aromatic rings in its structure that can promote allergic reactions to the humans. In this work, the main purpose was to synthesize new monomers from glycidyl methacrylate to use in dental restorative materials. Structural characterization of the monomers was carried out through FTIR and NMR 1H, and eight composites were produced from the new monomers, by addition of silane-treated alumino silicate particles (inorganic filler) and a photocuring system (camphorquinone and ethyl 4-dimethylaminebenzoate). The composites were analyzed by environmental scanning electronic microscopy and the water sorption and solubility, compressive strength and elastic modulus were determined. A commercial composite resin [Z100 (3M)] was used to comparison effect. The new composites presented general characteristics similar to the commercial ones; however, they didn t present the properties expected. This behavior was attributed to the lower degree of monomer reaction and to the granulometry and size distribution of the mineral filler in the polymeric matrix
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Heating rate is one of the main variables that determine a fire cycle. In industrial processes that use high temperatures, greater fire great can reduce the cost of production and increase productivity. The use of faster and more efficient fire cycles has been little investigated by the structural ceramic industry in Brazil. However, one of the possibilities that aims at modernizing the sector is the use of roller kilns and the inclusion of natural gas as fuel. Thus, the purpose of this study is to investigate the effect of heating rate on the technological properties of structural ceramic products. Clay raw materials from the main ceramic industries in the state of Rio Grande do Norte were characterized. Some of the raw materials characterized were formulated to obtain the best physical and mechanical properties. Next, raw materials and formulations were selected to study the influence of heating rate on the final properties of the ceramic materials. The samples were shaped by pressing and extrusion and submitted to rates of 1 °C/min, 10 °C/min and 20 °C/min, with final temperatures of 850 °C, 950 °C and 1050 °C. Discontinuous cycles with rates of 10 °C/min or 15 °C/min up to 600 °C and a rate of 20 °C/min up to final temperature were also investigated. Technological properties were determined for all the samples and microstructural analysis was carried out under a number of fire conditions. Results indicate that faster and more efficient fire cycles than those currently in practice could be used, limiting only some clay doughs to certain fire conditions. The best results were obtained for the samples submitted to slow cycles up to 600 °C and fast fire sinterization up to 950 °C. This paper presents for the first time the use of a fast fire rate for raw materials and clay formulations and seeks to determine ideal dough and processing conditions for using shorter fire times, thus enabling the use of roller kilns and natural gas in structural ceramic industries
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It is estimated that the Brazilian karst areas sum about 200.000 km2. The caves, one of the main components of karst, are important windows into the biological studies on hypogean environments. In Rio Grande do Norte are known 563 caves, and 476 of them are in the municipalities of Baraúna, Felipe Guerra, Governador Dix-Sept Rosado, Apodi and Mossoró, the Western region of the State. However, like in the rest of the country, the cave fauna of the State is still poorly understood. This study used data from invertebrates harvested in 47 caves and aimed to analyze the effect of environmental change between the dry and rainy seasons in the communities of cave invertebrates, characterize these communities and evaluate the relationships between morphological and biotic variables of the caves and surroundings, and to define priority areas for conservation of cave environments of the study area from biotic parameters. Strong effects were found in the community structure of cave invertebrates due environmental changes between seasons, with values of total richness, abundance, diversity and ecological complexity significantly higher in the rainy season. It was possible to assess how the morphology of the cave and the external environment variables affect the biotic system, so that the variety of resources, forest cover in the vicinity, the area of the cave and its entrance were the variables that best explained the structure communities of cave invertebrates in the region. High values of total richness of invertebrates (36,62 ± 14,04 spp / cave) and troglomorphic species (61 species, mean 1,77 ± 2,34 spp / cave) were found and, given the biological relevance in the context of the area national and the imminent anthropogenic pressures existing, we defined four priority areas for actions aiming cave biodiversity conservation in the region.
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The acidic galactan (AG) was obtained by extraction and proteolysis by acetone precipitation of the eggs of the mollusc Pomacea lineata. Its structure was elucidated by a combination of chemical analysis, the intrinsic viscosity and NMR spectroscopy 1D and 2D. Biological aspects of AG were evaluated by in vivo testing of healing and peritonitis induced (anti-inflammatory activity) and in vitro assays of cytotoxicity (MTT). This polymer showed a simple structure without the presence of sulfate and uronic acids in its structure. Its intrinsic viscosity and relative were evaluated at 0.44 ± 0.05 and 1.744± 0.07 dl.g-1. Spectroscopy showed that the AG has a constitution composed predominantly of β-D-galactosis, and β-D-glucosamine-NAcetil that comes in a smaller proportion in chain. The character of this acidic polysaccharide is given by the presence of pyruvate in the molecule, forming a cyclic acetal of six states, located in β-D-galactosis. The involvement of AG in the healing process was evaluated and the histological analysis revealed that there was so early in the process of healing, a great stimulation of macrophages with granuloma formation. Suggesting that AG may have promoted the advance of biological events required for tissue healing. In the trial of the GA-induced peritonitis showed dose dependent, demonstrating the anti-inflammatory effect at concentrations above 20 mg/kg, and confirming its inflammatory character and the concentration of 1mg/kg. In vitro tests used in the GA concentration of 1000 μg/mL showed proliferative activity by stimulating the growth of 3T3 cells, corroborating the findings in vivo and demonstrating the absence of cytotoxic activity
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This issue analises the unevenness in the brazilian system of public health care as an extension of socials inequities. It is a theoretical study based in a historical method, using empirical camp from academic, corporation and institution researchs, along the period 2002-2006. Equality and effectiveness in health systems are analitical basic cathegories grap in the root of the doctrine, principles and organization of the Unique Health System, in which sectorial actions are inserted. Discuss the estructural prodution and determined those inequalities through some social determiners of health system: income, land, food securitiy, nutritional situation, basic sanitation, epidemiological inequities and public management policy. Carry out a thematic review over health social production, it formlation and the goals of social policies, as well as the insertion of the equality principle in the assistance system, in the frame of the running public health regulations. It uses reflections that enlighted the correlation between the process of political-institutional actions and equity on health assistance. Analized the pertinency of sectorial reorganizational strategies on basic attendance, confronting the hipothesis that those strategies reinforce social inequities in health system, because it organize diferential assistance levels over not equal baselines. The results show up that social inequalities, even remaining, have had a small decrease; that the selectiviness of actual public policies and the duplication of the health system, increases the differences within and between the social classes and configures the assistance as inequal. The basic care system has great shortages that also appeares in middle and complex assistance levels. As conclusion, it remarks that the health assintance system, even with it integrality has limits; structural problems on material conditions of living and health system could not be reversed only with institutional legal arragements; by the contrary, in border conditions, these strategies produce policies that reinforce inequities, neglecting the equity principle of the system in which frame, they work. One patina of this tim
Avaliação histomorfométrica e ultra-estrutural da mucosa do cólon menor eqüino submetido a distensão
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Analyzes the factors that unleash violence by banalization of the problems and health questions of workers in a federal public institution, in Natal/RN. It analyzes transformations in the world of the work, with its politic, social and economic determinatives and its relation to the worker health. Boarding the violence in the work enviroment and its implications to the worker health, focusing on the banalization of problems faced by the workers as a kind of violence in and with the work. It was chosen an analitic methodology with qualitative approach, through the collection tecnic and information analyzes according to the thematic oral history, with recorders of authorized personal narratives, through individual interview with a semi-structured guide. In the analyzis of results it were made empiric cathegories: the daily work enviroment and its influence to the worker profession and life; the violence presents in the work enviroment and its consequences to the worker life and health; the banalization of the social injustice, due to violence against the worker that broked their dreams concerned to the nursing contribution. The results revealed the ordinary work of these workers showing enviromental and organizational unhealthy conditions, caracterized by physical and tecnical insecurity; absence and disqualification of instrumental and human supplies; overload and complexity service; bad distribution of the duties and pressure to the deadline and productivity, producing tension, conflict and anxiety related to the users, colleagues, superiors and to the duties. In the work enviroment, it were identified a external violence, caracterized by physical and verbal aggresion, psychic suffering, worker depreciation; and internal, caracterized by: moral and psychological molestations and accupational structural violence. These kinds of violence bring consequences to the life, that is, professional, economic and moral order of factors and to the health by biological, mental and emocional factors. The banalization of social injustice during the daily work was discussed in the aspects of banalization of problems and work conditions, the health, qualification banalizations and professional valorization. The workers expectatives pointed out to the necessity of: secure conditions of work; trainning and tecnical assistance; politics of attention to the physical, mental and social health to the workers and their family. We conclude the enviromental and organizational conditions of the workers interviewed do not offer physical and tecnical security that they need to the execution of their activities, neither offer comfort or physical and psychological satisfactions. The politic the instituition has used points out to the depreciation and inhumanization of them producing feelings as unsatisfaction, frustation and indignation related to the institution and the work, bringing suffering and physical and mental sicking. We noticed the most terrible violence found in the work enviroment is the banalization of social injustice related do the problems and health of these workers, producing a slowly debility and simbolic death of their lifes. Therefore, it is necessary the implementation of a politic that promotes assurance, health and integral education, valorization and humanization of these workers
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The demographic and epidemiological transition process caused by a declining in birth rates and in mortality, also changes occurred in morbidity and mortality is represented by the increasing of the aging population and the raising of chronic diseases. These diseases are characterized by multiple etiologies, risk factors, long latency period, a prolonged evolution, non-infectious origin and it has association with functional impairment and disability. Thus, elderly with chronic non-communicable disease has priority because they belong to a vulnerable group to get affection of comorbidities in aging, with increased demand and spending on health services. This study is aimed to analyse the understanding of elderly people with chronic non comunicable disease in the medium complexity service as a contribution to the improvement of health care in the city of Natal / RN. This is a descriptive and exploratory study with a quantitative approach, carried out at the Specialized Center for Elderly Health Care and at the Pescadores Hospital. The population was composed of 4,180 persons with a sample of 124 elderly aged above 60 years, attended in these medium complexity services. The instrument, a structured form, adapted from a questionnaire for monitoring risk and protective factors for chronic disease of the Ministry of Health. To collect data was was used the interview form containing demographic data, habits, health status and health care services. The results were processed using the Statistical Package for Social Science, version 18.0, analyzed by simple statistics. It was found that most seniors were female, predominantly between 70 and 74 years old, married, with a brown skin tone and Catholic religion, more than half had incomplete basic education, family income between one to two minimum wages and living with their families. Regarding the interviewers lifestyle, 94.4%, of them ate chicken and 97.6%, fruits, it was observed a reduction in smoking, alcoholism habits and physical activity according to the increasing age, 58.1 and 18.5% had insomnia18,5 % used sleeping pills. The elderly (51.6%) reported using services in times of sickness, seeking primary care at first (30.6%), 52% did not receive referral and was looking for free demand (38.7%). The most reported morbidity was hypertension, followed by musculoskeletal disorders. Regarding the difficulties in seeking health services, the delay in treatment and the waiting line were the most cited by the elderly. Almost all of them reported no activities to promote health in these services and those who received individual counseling on chronic diseases. Almost always, the health professionals who care of them, were mostly doctors followed by nurses. Based on the results presented, it is considered that the health services of medium complexity must undergone a more continuous dialogue with other attention level and focus on actions of health promotion and prevention. It is also recommended the necessity for qualified professionals to delivery health care to elderly and the implementation of protocols by a multidisciplinary health team, intending to provide better and continous care for the elderly with chronic diseases. The healthcare professionals who served them, were mostly physicians, followed by nurses. Through the results presented, it is considered that the medium complexity healthcare services need to perform a more continuous dialogue with the other levels of attention focusing attention to the health promotion and prevention actions. It is also recommended the necessity for qualified professionals to delivery healthcare for the elderly, in addition, a protocol implementation for the multidisciplinary health care team, to provide better care, and also the care continuity to elderly with chronic diseases
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Venous ulcers are lesions resulting from chronic venous insufficiency, venous valvular abnormalities and venous thrombosis. Its occurrence has been growing with the increase in life expectancy of the world population. Considered as fundamental aspects in the approach to the person with venous ulcer care with the interdisciplinary approach, adoption of protocol-specific knowledge, technical skill, coordination between levels of care complexity of the Health System and active participation of patients and their families, a holistic perspective. The construction of a clinical protocol for people with venous ulcers can help professionals of high complexity services in patient assessment and the establishment of quality care in a systematic way and focused on the factors that interfere with wound healing. Thus, this study aimed to analyze the evidence of validation of a clinical protocol for people with venous ulcers treated at high-complexity services. This is a methodological study with a quantitative approach, developed in three stages: literature review, evidence of content validity and evidence of validation in the clinical context. Approved by the Federal University of Rio Grande do Norte Research Ethics Committee (Opinion: 147.452 and CAAE: 07556312.0.0000.5537). The literature review was conducted in August and September 2012, becoming the basis for the construction of the protocol. Then the evidence of content validity, which included 53 judges (experts) selected by the Lattes platform to evaluate the protocol items was performed. The judges were contacted by e-mail and rated the protocol via Google Docs
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The main objective of this thesis was the study of bracing panels of structural masonry, by applying the Finite Element Method and Strut and Tie Method. It was analyzed the following aspects: the effect of orthotropy on the behavior of the panels; distribution of horizontal forces between panels for buildings; comparison between Equivalent Frame and Finite Elements models; panels design with the Strut and Tie Method. The results showed that one should not disregard the orthotropy, otherwise this can lead to models stiffer than the real. Regarding the distribution of horizontal forces, showed that the disregard of lintels and shear deformation leads to significant differences in the simplified model. The results showed also that the models in Finite Element and Equivalent Frame exhibit similar behavior in respect to stiffness of panels and stress distribution over the sessions requested. It was discussing criteria for designing Strut and Tie Method models in one floor panels. Then, the theoretical strength these panels was compared with the rupture strength of panels tested in the literature. The theoretical maximum strength were always less than the rupture strength of the panels obtained in tests, due to the fact that the proposed model cannot represent the behavior of the masonry after the start of the panel cracking due to plasticization of the reinforcement
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Usually masonry structures has low tension strength, hence the design to flexural efforts can results in high reinforcement ratio, specification of high unit and prism strength, structural members with larger section dimensions and modification in structural arrangement to be possible to use masonry members. The main objective of this study is to evaluate the stiffness, the efforts distribution and the effect of horizontal elements (girders) and vertical elements (counterforts) distribution on the behavior of masonry blocks retaining walls. For this purpose, numerical modeling was performed on typical retaining wall arrangements by varying the amount and placement of horizontal and vertical elements, beyond includes elements simulating the reactions of the soil supporting the foundation of the wall. The numerical modeling also include the macro modeling strategy in which the units, mortar and grout are discretized by a standard volume that represents the masonry elastic behavior. Also, numerical model results were compared with those ones of simplified models usually adopted in bending design of masonry elements. The results show horizontal displacements, principal and shear stresses distribution, and bending moments diagrams. From the analysis it was concluded that quantity and manner of distribution of the girders are both important factors to the panel flexural behavior, the inclusion of the foundation changed significantly the behavior of the wall, especially the horizontal displacements, and has been proposed a new way of considering the flanges section of the counterforts
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In academia, it is common to create didactic processors, facing practical disciplines in the area of Hardware Computer and can be used as subjects in software platforms, operating systems and compilers. Often, these processors are described without ISA standard, which requires the creation of compilers and other basic software to provide the hardware / software interface and hinder their integration with other processors and devices. Using reconfigurable devices described in a HDL language allows the creation or modification of any microarchitecture component, leading to alteration of the functional units of data path processor as well as the state machine that implements the control unit even as new needs arise. In particular, processors RISP enable modification of machine instructions, allowing entering or modifying instructions, and may even adapt to a new architecture. This work, as the object of study addressing educational soft-core processors described in VHDL, from a proposed methodology and its application on two processors with different complexity levels, shows that it s possible to tailor processors for a standard ISA without causing an increase in the level hardware complexity, ie without significant increase in chip area, while its level of performance in the application execution remains unchanged or is enhanced. The implementations also allow us to say that besides being possible to replace the architecture of a processor without changing its organization, RISP processor can switch between different instruction sets, which can be expanded to toggle between different ISAs, allowing a single processor become adaptive hybrid architecture, which can be used in embedded systems and heterogeneous multiprocessor environments
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Bayesian networks are powerful tools as they represent probability distributions as graphs. They work with uncertainties of real systems. Since last decade there is a special interest in learning network structures from data. However learning the best network structure is a NP-Hard problem, so many heuristics algorithms to generate network structures from data were created. Many of these algorithms use score metrics to generate the network model. This thesis compare three of most used score metrics. The K-2 algorithm and two pattern benchmarks, ASIA and ALARM, were used to carry out the comparison. Results show that score metrics with hyperparameters that strength the tendency to select simpler network structures are better than score metrics with weaker tendency to select simpler network structures for both metrics (Heckerman-Geiger and modified MDL). Heckerman-Geiger Bayesian score metric works better than MDL with large datasets and MDL works better than Heckerman-Geiger with small datasets. The modified MDL gives similar results to Heckerman-Geiger for large datasets and close results to MDL for small datasets with stronger tendency to select simpler network structures
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The red ceramics and structural ceramics, as they are known, include ceramic materials made by blocks of seals and structures, bricks, tiles, smail flagstones manacles, rustic floors and ornamental materials. Their fabrication uses raw material such as clay and clay sites, with some content of impurity. It has good durability and mechanical strength to compression, low cost, making it one of the mainly used materials in civil engineering. The incorporation of many industrial activities residue to ceramic products is a technological alternative for reducing the environmental impact caused by its carefree disposal. This incorporation can promote chemical change and inertness of metals from residue, by fixation in the glassy phase of ceramic during the burning stage. The main aim of this project is to study the technical feasibility of the addition of ceramic oven ash into formulations of mass for structural ceramics. In this project two kinds of clay (plastic and non-plastic) were used, as well as the ash from firewood used in the process of burning of structural ceramics. A group of experiments was outlined, which permitted the evaluation of the influence of the burning cycle in different temperatures of the ash content in formulations for ceramic blocks through technological properties, mechanical behavior and microstructure. Five samples were processed of each one of the masses of plastic and non-plastic clay without addition of ash and with addition of ash on the percentages of 10 % and 20 %, for temperatures of 850 °C, 950 °C, 1050 °C and 1150 °C, obtained through sinterization process. Among the studied compositions, the one which presented best performance was the mass of clay with 10 % of ash, at temperature of 1150 °C, with the smallest absorption of water, the smallest apparent porosity, specific apparent mass a bit over the others and greatest mechanical resistance to flexion. The composition made confirmed the technical feasibility of the use of ash in the mass for structural ceramics with maintenance of its necessary characteristics for its purposes
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There are a number of damaging mechanisms that various materials can suffer in service. However, when working with polymer composite materials, this is something that requires analysis, especially when exposed to adverse environmental conditions. Thus, the objective of the present thesis is the study of the direct influence of environmental aging and the form of hybridization of the reinforcement woven on the structural stability, surfacedegradation and fracture process of polymer composites laminates. For this, the development of two polymer composite laminates was necessary, where one of them was reinforced with a bi-directional woven with hybrid strandsofkevlar-49/glass-Efibers, and the other also with a bi-directionalwoven, however with weft and warpformed of alternating strandsof Kevlar-49 fibers and glass-E fiber The reinforcementwoven are industrially manufactured. Both laminates use a polyester resin as a matrixand are made up of four layers each. All laminates were industrially prepared by the hand lay-up method of manufacturing. To do this, test specimens were manufactured of the respective laminates and submitted to environmental aging accelerated through the aging chamber. They were exposed to alternating cycles of UV radiation and moisture (heated steam) for a standard defined period. At the end of the exposure period the specimens were subjected to mechanical tests of uniaxial tensile and bending in three points and to the characterizationsof the fracture and surface deterioration. In addition, they were submitted to a structural degradation assessment by the measurement of mass variation technique (MMVT) and the measurement of thickness variation technique (MTVT), this last technique being developed in this thesis. At the end of the analysis it was observed that the form of hybridization of the reinforcement woven and the aging process directly influence with losses or gain in mechanical properties, with losses in the structural degradation and in the formation and propagation of damage mechanism of the developedcomposite laminates