105 resultados para Leito fluidizado (Pirometalurgia)


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This work depicts a study of the adsorption of carbon dioxide on zeolite 13X. The activities were divided into four stages: study batch adsorption capacity of the adsorbent with synthetic CO2 (4%), fixed bed dynamic evaluation with the commercial mixture of gases (4% CO2, 1.11% CO, 1 2% H2, 0.233% CH4, 0.1% C3, 0.0233% C4 argon as inert closing balance), fixed bed dynamic modeling and evaluation of the breakthrough curve of CO2 originated from the pyrolysis of sewage sludge. The sewage sludge and the adsorbent were characterized by analysis TG / DTA, SEM, XRF and BET. Adsorption studies were carried out under the following operating conditions: temperature 40 °C (for the pyrolysis of the sludge T = 600 °C), pressures of 0.55 to 5.05 bar (batch process), flow rate of the gaseous mixture between 50 - 72 ml/min and the adsorbent masses of 10, 15 and 20 g (fixed bed process). The time for the adsorption batch was 7 h and on the fixed bed was around 180 min. The results of this study showed that in batch adsorption process step with zeolite 13X is efficient and the mass of adsorbed CO2 increases with the increases pressure, decreases with temperature increases and rises due the increase of activation temperature adsorbent. In the batch process were evaluated the breakthrough curves, which were compared with adsorption isotherms represented by the models of Langmuir, Freündlich and Toth. All models well adjusted to the experimental points, but the Langmuir model was chosen in view of its use in the dynamic model does not have implications for adsorption (indeterminacy and larger number of parameters such as occurred with others) in solving the equation. In the fixed bed dynamic study with the synthetic gas mixture, 20 g of mass adsorbent showed the maximum adsorption percentage 46.7% at 40 °C temperature and 50 mL/min of flow rate. The model was satisfactorily fitted to the three breakthrough curves and the parameters were: axial dispersion coefficient (0.0165 dm2/min), effective diffusivity inside the particle (dm2/min 0.0884) and external transfer coefficient mass (0.45 dm/min). The breakthrough curve for CO2 in the process of pyrolysis of the sludge showed a fast saturation with traces of aerosols presents in the gas phase into the fixed bed under the reaction process

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Studies show the great influence of free radicals and other oxidants as responsible for aging and degenerative diseases. On the other hand, the natural phenolic compounds has shown great as antioxidants to inhibit lipid peroxidation and lipoxygenase in vitro. Among these, is highlighted trans-resveratrol ( 3,5,4 `- trihydroxystilbene ) phenolic compound , characterized as a polyphenol stilbene class. The vegetables popularly known as "Azedinha" (Rumex Acetosa) has trans-resveratrol in its composition and from this, the present work aimed to study on the supercritical extraction and conventional extraction (Soxhlet and sequential) in roots of Rumex Acetosa, evaluating the efficiency of extractive processes, antioxidant activity, total phenolic content and quantification of trans-resveratrol contained in the extracts. Extractions using supercritical CO2 as solvent, addition of co-solvent (ethanol) and were conducted by the dynamic method in a fixed bed extractor. The trial met a 23 factorial design with three replications at the central point, with the variable reply process yield and concentration of trans-resveratrol and pressure as independent variables, temperature and concentration of co-solvent (% v/v). Yields ( mass of dry extract / mass of raw material used ) obtained from the supercritical extraction ranged from 0,8 to 7,63 % , and the best result was obtained at 250 bar and 90 °C using the co-solvent 15% ethanol (% v/v). The value was calculated for YCER a flow rate of 1,0 ± 0,17 g/min resulting in 0,0469 CO2 ( g solute / g solvent ). The results of the mass yield varied between conventional extractions 0,78 % ( hexane) and 9,97 % (ethanol). The statistical model generated from the data of the concentration of trans-resveratrol performed as meaningful and predictive for a 95% confidence. GC analysis on HPLC (High Performance Liquid Chromatography), transresveratrol was quantified in all extracts and concentration values ranged between 0,0033 and 0,42 ( mg / g extract) for supercritical extracts and between 0,449 and 17,046 (mg / g extract) to conventional extractions and therefore, the Soxhlet extraction with ethanol for more selective trans-resveratrol than the supercritical fluid. Evaluation of antioxidant (radical method to sequester 2,2- diphenyl-1- picryl - hydrazyl - DPPH) the supercritical extracts resulted in EC50 values (concentration effective to neutralize 50% of free radicals) of between 7,89 and 18,43 mg/mL , while resulting in a Soxhlet extraction with EC50 values in the range of 6,05 and 7,39 mg/mL. As for quantification of the phenolic compounds (Method Spectrophotometer Folin-Ciocalteau) the supercritical extracts resulted in values between 85,3 and 194,79 mg GAE / g extract, whereas values derived from the Soxhlet extract resulted in values between 178,5 and 237,8 mg GAE / g extract. The high antioxidant activity can not be attributed solely to the presence of phenolic compounds, but the presence of other antioxidants in the existing Rumex acetosa

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Seeking a greater appreciation of cheese whey was developed to process the hydrogenation of lactose for the production of lactitol, a polyol with high added value, using the catalyst Ni / activated carbon (15% and 20% nickel), the nitride Mo2N, the bimetallic carbide Ni-Mo/ activated carbon and carbide Mo2C. After synthesis, the prepared catalysts were analyzed by MEV, XRD, laser granulometry and B.E.T. The reactor used in catalytic hydrogenation of lactose was the type of bed mud with a pressure (68 atm), temperature (120 oC) and stirring speed (500 rpm) remained constant during the experiments. The system operated in batch mode for the solid and liquid and semi-continuous to gas. Besides the nature of the catalyst, we studied the influence of pH of reaction medium for Mo2C carbide as well as evaluating the character of the protein inhibitor and chloride ions on the activity of catalysts Ni (20%)/Activated Carbon and bimetallic carbide Ni-Mo/Activated Carbon. The decrease in protein levels was performed by coagulation with chitosan and adsorption of chloride ions was performed by ion exchange resins. In the process of protein adsorption and chloride ions, the maximum percentage extracted was about 74% and 79% respectively. The micrographs of the powders of Mo2C and Mo2N presented in the form of homogeneous clusters, whereas for the catalysts supported on activated carbon, microporous structure proved impregnated with small particles indicating the presence of metal. The results showed high conversion of lactose to lactitol 90% for the catalyst Ni (20%)/Activated Carbon at pH 6 and 46% for the carbide Mo2C pH 8 (after addition of NH4OH) using the commercial lactose. Monitoring the evolution of the constituents present in the reaction medium was made by liquid chromatography. A kinetic model of heterogeneous Langmuir Hinshelwood type was developed which showed that the estimated constants based catalysts promoted carbide and nitride with a certain speed the adsorption, desorption and production of lactitol

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Nowadays, Brazil has both the greatest goat herd and the greatest goat milk production of South America. The state of Rio Grande do Norte, located in northeast of Brazil, has an average year production of three thousand cubic meters of goat milk in natura. Part of this milk production is homemade and it comes from small farms, which unite in rural cooperatives created to encourage the production and implementation of industrial processes for preservation and processing of milk. Results presented by literature and obtained from preliminary essays in this thesis show that non conventional dryer of spouted bed with inert particles is able to produce powder milk from in natura milk (cattle or goat), with the same quality of spray dryer, however, operating at low cost. The method of drying in spouted bed consists of injecting milk emulsion on the bed of inert particles gushed by hot air. This emulsion covers the particles with a thin film, which dries and is reduced to powder during the circulation of inerts inside the bed. The powder is dragged by exhaustion air and separated in the cyclone. The friction among particles resulted from the particles circulation, encourages high taxes of shear in the thin film of emulsion, breaking the cohesive forces and making this process possible. Studying the drying process and the powder goat milk production in one unit of spouted bed with inert particles, seeing the development of a low cost technological route for powder milk production is the aim of this thesis. The powder milk produced by this route must attend the local demand of food industries which need an intermediate product to be used as a food ingredient (ice-cream, milk candy). In order to reach this aim, this thesis approaches the aspects related to physical, thermodynamics and physic-chemicals characteristics of goat milk, whose complete data are still inexistent in the literature. The properties of materials are of great importance to the project of any process which involves the operations of transportation of movement, heat and mass quantity, such as the dryers which operate in fluid dynamically active regime, like the spouted bed. It was obtained new data related to the goat milk properties in function of concentration of solids and temperature. It is also important to mention the study developed about the kinetic of solids retention in the bed of inert particles during the drying of goat milk. It was found more adequate processes conditions to the proposed technological route to be implemented in small and micro-industries, with simplifications in the system of milk injection as well as in the form of operation of the dryer. Important data were obtained for a posterior stage of this research which involves the v modeling, simulation, control and optimization of the process. The results obtained in this thesis, in relation to process performance as well as to the quality of produced powder milk validate the proposal of using the spouted bed dryer in the production of powder goat milk

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Biosurfactants are molecules produced by microorganisms mainly bacteria as Pseudomonas and Bacillus. Among the biosurfactants, rhamnolipids play an important role due to their tensoactive as well as emulsifying properties. Besides can be produced in a well consolidated way the production costs of biosurfactants are quite expansive mainly if downstream processing is goning to be considered. Actually, attention has been given to identification of biosurfactants as well as optimization of its fermentative processes including downstream ones. This work deals with the development of strategies to recovery and purification of rhamnolipids produced by Pseudomonas aeruginosa P029-GVIIA using sugar-cane molasses as substrate. Broth free of cells was used in order to investigate the best strategies to recovery and purification produced by this system. Between the studied acids (HCl and H2SO4) for the acid precipitation step, HCl was the best one as has been showed by the experimental design 24. Extraction has been carried out using petroleum ether and quantification has been done using the thioglycolic acid method. Adsorption studies were carried out with activated carbon in a batch mode using a 24 experimental design as well as combined with an hydrophobic resin Streamline Phenyl aiming to separate the produced biosurfactant. Biosurfactant partial identification was carried out using High Performance Liquid Chromatography (HPLC). Experiments in batch mode showed that adsorption has been controlled mainly by pH and temperature. It was observed a reduction of 41.4% for the liquid phase and the solid phase it was possible to adsorb up to 15 mg of rhamnolipd/g of activated carbon. The kinetics of adsorption has been well fitted to a pseudo-first order reaction with velocity constant (k1) of 1.93 x 10-2 min-1. Experiments in packed bed ranging concentration on eluent (acetone) has been shown the highest recovery factor of 98% when pure acetone has been used. The combined effect if using activated carbon with an hydrophobic resin Streamline Phenyl has been shown successful for the rhamnolipids purification. It has been possible to purify a fraction of the crude broth with 98% of purity when the eluted of activated carbon packed bed was used with pure acetone

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Amorphous silica-alumina and modified by incipient impregnation of iron, nickel, zinc and chromium were synthetized in oxide and metal state and evaluated as catalysts for the chloromethane conversion reaction. With known techniques their textural properties were determined and dynamics techniques in programmed temperature were used to find the acid properties of the materials. A thermodynamic model was used to determine the adsorption and desorption capacity of chloromethane. Two types of reactions were studied. Firstly the chloromethane was catalytically converted to hydrocarbons (T = 300 450 oC e m = 300 mg) in a fixed bed reactor with controlled pressure and flow. Secondly the deactivation of the unmodified support was studied (at 300 °C and m=250 g) in a micro-adsorver provided of gravimetric monitoring. The metal content (2,5%) and the chloromethane percent of the reagent mixture (10% chloromethane in nitrogen) were fixed for all the tests. From the results the chloromethane conversion and selectivity of the gaseous products (H2, CH4, C3 and C4) were determined as well as the energy of desorption (75,2 KJ/mol for Ni/Al2O3-SiO2 to 684 KJ/mol for the Zn/Al2O3-SiO2 catalyst) considering the desorption rate as a temperature function. The presence of a metal on the support showed to have an important significance in the chloromethane condensation. The oxide class catalyst presented a better performance toward the production of hydrocarbons. Especial mention to the ZnO/Al2O3-SiO2 that, in a gas phase basis, produced C3 83 % max. and C4 63% max., respectively, in the temperature of 450 oC and 20 hours on stream. Hydrogen was produced exclusively in the FeO/Al2O3-SiO2 catalysts (15 % max., T = 550 oC and 5,6 h on stream) and Ni/SiO2-Al2O3 (75 % max., T = 400 oC and 21,6 h on stream). All the catalysts produced methane (10 à 92 %), except for Ni/Al2O3-SiO2 and CrO/Al2O3-SiO2. In the deactivation study two models were proposed: The parallel model, where the product production competes with coke formation; and the sequential model, where the coke formation competes with the product desorption dessorption step. With the mass balance equations and the mechanism proposed six parameters were determined. Two kinetic parameters: the hydrocarbon formation constant, 8,46 10-4 min-1, the coke formation, 1,46 10-1 min-1; three thermodynamic constants (the global, 0,003, the chloromethane adsorption 0,417 bar-1, the hydrocarbon adsorption 2,266 bar-1), and the activity exponent of the coke formation (1,516). The model was reasonable well fitted and presented a satisfactory behavior in relation with the proposed mechanism

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The present work has as objective the knowledge of the process of drying of the cephalothorax of shrimp to give support the industry to make possible the use of this byproduct. In this sense, the process conditions in this tray dryer and spouted bed were analyzed. With these results, it was projected and constructs a dryer with specific characteristics for the drying of the cephalothorax. The desorption isotherms were obtained by the dynamic method in the temperatures of 20, 35 and 50º C and in the interval of 10-90% of relative humidity. It was observed that the product in form of powder can be conserved with larger stability for lower relative humidity to 40%. The curves of drying of the dryer of fixed bed were adjusted for the models: single exponential, biparametric exponential and Page. The model biparametric exponential more adequately described all the drying conditions studied. The tests carry out in spouted bed showed high drying rate for the material in the paste form in beds active dynamicly-fluid, provely the necessity of a feeding in shorter intervals of time to increase the thermal efficiency of the process. The projected dryer, be considered the obtained results, it was a rotary dryer with inert bed, feed co-current, discharge in cyclone to take place the separation gas-solid, and feed carry out in intervals of 2 minutes. The optimization of the equipment projected it was accomplished used the complete factorial experimental design 24, this had as independent variables temperature velocity of the air, feed flow rate and encapsulated concentration (albumin), as variables answers the thermal efficiency, the moisture content of obtained powder, total time of test and the efficiency of production of powder in several points of processing. The results showed that the rotary dryer with inert bed can present, also, good results if applied industrially

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In the last decade, biological purification of gaseous waste has become an important alternative to many conventional methods of exhaust air treatment. More recently, biofiltration has proved to be an effective and inexpensive method for the treatment of air contaminated with volatile organic compounds (VOCs). A biofilter consists in a reactor packed with a porous solid bed material, where the microorganisms are fixed. During the biofiltration process, polluted air is transported through the biofilter medium where the contaminant is degraded. Within the biofilm, the pollutants in the waste gases are energy and carbon sources for microbial metabolism and are transformed into CO2, water and biomass. The bed material should be characterized by satisfactory mechanical and physical properties as structure, void fraction, specific area and flow resistance. The aim of this research was the biofilter construction and study of the biological degradation of ethanol and toluene, as well as the modeling of the process. Luffa cylindrica is a brazilian fiber that was used as the filtering material of the present work. The parameters and conditions studied were: composition of nutrients solution; effect of microflorae strains, namely Pseudomanas putida and Rhodococcus rhodochrous; waste gas composition; air flow rate; and inlet load of VOCs. The biofilter operated in diffusion regime and the best results for remotion capacity were obtained when a microorganisms consortion of Pseudomanas putida and Rhodococcus rhodochrous,were used, with a gas flow rate of 1 m3.h-1 and molar ratio nitrogene/phosphore N/P=2 in the nutrients solution. The maximum remotion capacity for ethanol was around 90 g.m-3.h-1 and 50 g.m-3.h-1 to toluene. It was proved that toluene has inhibitory effect on the ethanol remotion When the two VOCs were present in the same waste gas, there was a decrease of 40% in ethanol remotion capacity. Luffa cylindrica does not present considerable pressure drop. Ottengraf and van Lith models were used to represent the results obtained for ethanol and toluene, respectively. The application of the transient model indicated a satisfactory approximation between the experimental results obtained for ethanol and toluene vapors biofiltration and the ones predicted it

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The accelerated growth of urban regions have produced relevant effects on water resources. Urban regions need an adequate institutional structure that can be able to face environmental demands and the adverse effects of land use on water resources. This study aims at analysing land use effects on heavy metals concentration in sediments and water, as well as making a comparative analysis involving water physical-chemical parameters. Applied methodology included both in loco water parameters measurement and water and bed sediment sampling at 8 sections along the fluvial system. Sample analysis was performed in laboratory in order to measure heavy metal concentrations. It was measured metal concentrations of Al, Cu, Pb, Cd, Fe, Ni and Zn. Once the samples were subjected to acid digestion (method 3050B), concentration values were measured by using atomic absorption spectrometry by flame (ICP-FLAA). The analysis results were compared with normative reference, these standards is intended to assess the risks of toxic substances in sediment and water management programs. The normative reference used in this work were: a) Ontario Ministry of the Environment and Energy (OMEE, 1993) b) Normative Netherlands (VROM, 2000); c) Normative Canadian (CCME, 1999); d) United States Environmental Protection Agency (USEPA, 1977), e) CONAMA Resolution No. 344/2004; f) CONAMA Resolution No. 357/2005. The high concentrations of iron (38,750 mg.g-1), Lead (1100 mg.g-1), Nickel (100 μg.g-1) and zinc (180 μg.g-1) detected sediments confirm the state of degradation of the aquatic system. Iron concentrations (1.08 mg.L-1), Aluminum (0.6 mg.L-1) and phosphorus (0.05 mg.L-1) present in the water are outside the established standards for human consumption

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The sludge generated in stabilization ponds can be designed for various purposes, among them we mention agricultural use, recovery of degraded areas and civil construction. The choice of these alternatives should be made based on qualitative and quantitative characteristics of the sludge. In this context, this study characterized the digested sludge from an anaerobic lagoon in Cidade do Natal/RN, which deals exclusively with residues of depleted septic tanks and pits. The sludge showed levels of macro and micronutrients that confirm its potential for agriculture, with 139.49 g.kg -1 organic matter, 15.40 g.kg-1 nitrogen and metal concentrations below those required by Resolution No. 375/06 of CONAMA, besides the absence of fecal coliform and less than 0.15 viable helminthes eggs/g, on average. The particle size distribution showed that most of the particles have a diameter similar to the sand, allowing the replacement of this input, for example. Analysis of the leachate and of the sludge solubilized classified as non-inert and non-hazardous according to NBR 10.004/04. The volume produced in three years of operation by the pond was 1903.50m³, equivalent to approximately 400 kg of dry sludge. Overall, the concentrations of the parameters were similar to literature, although none of them addresses sludge anaerobic pond treating sewer from septic tanks and pits.The sludgepresents technical feasibility to various types of use, however the cost of dewatering and especially with transport can derail it. It needs to be made a more thorough study of the costs to prove its economic viability

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Nowadays, technology has a direct influence on the relationship student and teacher have with language. The internet is a powerful tool in helping work with the language and, through it, the knowledge comes to the student easily and intensely. Furthermore, this facility has enhanced and made visible what has been called, within the University community, "plagiarism generation." This work assumes that this generation has, in their written texts, symbolic movements similar to those of "copy and paste" applied to research work carried out by high school students. Taking this as starting point, this dissertation aims to analyze how high school students of the 1st year from a school in Natal (RN) construct texts, under the movements known as "Ctrl + c" and "Ctrl + v", with reference to the text of the "other". More specific issues are behind the general objective, namely: 1. how the student appropriates the source-text when he copies and pastes? 2. What are the categories of analysis that allow us to look analytically and theoretically for the "ctrl + c / ctrl + v" practice made by the student? 2. how the studies developed in the fields of "Genetic Criticism" (Grésillon, 1987), the "school manuscripts" (Calil, 2004) and "paraphrase" (Fuchs, 1982) may help in working with writing in the classroom standing as a possible way to minimize the copy and paste effects in the students texts? Thus, we observe the categories of analysis that allow us to look, theoretically and analytically, for the symbolic ritual of the "ctrl + c" (copy) and "ctrl + v" (paste) in high school. Our study shows that the student text is a "hybrid body" whose writing is a drawing entanglement because of the presence of the foreign text, verbatim, and the presence of linguistic elements to paraphrase the original text.This textual embodiment has, behind it, certain operations, namely: replacing, moving, adding and deleting statements. Given the specificity of the data and the research objectives, this study aligns with qualitative research methods (SILVERMAN, 2009) and falls within the knowledge field of Applied Linguistics, which is characterized especially by investigating problems, phenomena in which language in a real situation is taken as central (BRUMFIT, 1995).Theoretically, our work follows the approach of studies on the paraphrase (Fuchs, 1982, 1994a, 1994b; DAUNAY, 1997, 1999, 2002a, 2002b), the studies developed in the field of Genetic Criticism (Grésillon, 1987, 1994, 1992, 2008 ) and those developed by Eduardo Calil (2004) on "school manuscripts"

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The present dissertation analyses the philosophy of Friedrich Nietzsche (1844-1900) and the short story written by João Guimarães Rosa (1908-1967), A hora e vez de Augusto Matraga (1946) seeking to point out the possibility of the philosophic application of some Nietzschean ideas to enlarge the aesthetic value of the short story. It has been especially aimed at applying the concept of the noble superior being described by Nietzsche, the ubermensch, to the hero s ontological nature, Augusto Matraga. Nietzsche s postulates of the will to power, the elements suggested of the trial between Dionysus and Apollo and the ascetic ideal, will be especially relevant to this work, which intends to establish until what point the hero can be conceived as a good ascetic person, in so far as his noble ontological nature trespass the Christian morality, bringing him closer to the man who, according to Nietzsche, is beyond good and evil. Some Heideggerian concepts will also be relevant in order to reinforce the idea that the judgment created about Matraga is just an appearance that does not contemplate his essential Being, contributing to veil his real tragic-ontological valour, what implies that the aesthetic power of the short has been under valued

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The public dental services in Brazil were limited, practically, to the basic care, so that the specialized services acted, up to 2002, no more than 3,5% of the total of clinical procedures. That lower offer reveals the difficulty of continuity of the attention, that is, the comprehensiveness in the assistance, particulary, the reference and counter-reference system. Brasil Sorridente search to supply those needs when proposing Speciality Dental's Centers(CEOs Centros de Especialidades Odontológicas, Brazil) to compose the services of average complexity. In 2005, Ministry of Health enabled the three CEOs of Natal, located in the North II, East and West Sanitary Districts. This investigation evaluated the implantation of these CEOs, as support of the family health care teams, in the perspective of organization of the services in assistencial nets in Natal/RN. It was a study of evaluation, with qualitative approach and some quantitative data as contribution. Dentists, users and managers were interviewed to identify and to understand their perceptions, relationships and experiences in the daily of the services. The conceptual base that orientated the investigation was the principle of comprehensiveness, in its operational sense of the hierarchization in health attention levels. The collection of data was done with documental research, direct observation and semi-structured interview. The analysis was accomplished by triangulation of the extracted content from the used techniques and sources of interviewed groups depositions, looking for theoretical-conceptual support in specific bibliography. The results pointed aspects that go away from the comprehensiveness like: low resolution of problems in the basic net; little valorization of the space in the health units; traditional models of access to health services, insufficient offer for some specialties, compromising the reference and counter-reference system; practices centered in procedures in the CEO; bureaucratic directions from basic care to the specialized service; disintegrated and disjointed system among levels of attention; disrespect to the municipal protocol. On the other hand, there is an approach of compreensiveness in situations like: increase of the access and covering in the Family Health Strategy (ESF Estratégia Saúde da Família, Brazil); larger approach between professional and user; tendency to the quantitative and qualitative growth of specialized actions; punctual initiatives of relationships among levels; existence of protocol to guide professionals

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Periodontal infections consist of a group of inflammatory conditions caused by microorganisms that colonize the tooth surface through the formation of dental biofilm. Chronic infections such as periodontitis have been associated to the development and progression of atherosclerosis. AIM: Detect cultivatable and non-cultivatable periodontopathogenic bacteria in atheromatous plaques; search for factors associated to the presence of these bacteria in the atheromatous plaques and characterize the presence of cultivatable and non-cultivatable bacteria in these plaques. METHODOLOGY: A cross-sectional study was performed with a sample of 30 patients diagnosed with atherosclerosis in the carotid, coronary or femoral arteries and surgically treated with angioplasty and stent implant, bypass or endarterectomy. The plaques were collected during surgery and analyzed using the PCR molecular technique for the presence of the DNA of the cultivatable bacteria Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis and Treponema denticola and of the non-cultivatable Synergistes phylotypes. The patients were examined in the infirmary, after the surgery, where they also responded to a questionnaire aimed at determining factors associated to the presence of periodontopathogenic bacteria in the atheromatous plaques. RESULTS: All patients with tooth (66,7%) possessed disease periodontal, being 95% severe and 65% widespread. No periodontopathogenic bacteria were found in the atheromatous plaques. However, four samples (13.3%) were positive for the presence of bacteria. Of these, three participants were dentate, being two carriers of widespread severe chronic periodontite and one of located severe chronic periodontitis. None of them told the accomplishment of procedures associated to possible bacteremia episodes, as treatment endodontic, extraction the last six months or some procedure surgical dental. CONCLUSION: The periodontopathogenic bacteria studied were not found in the atheromatous plaques, making it impossible to establish the prevalence of these pathogens or the factors associated to their presence in plaques, the detection of positive samples for bacteria suggests that other periodontal and non-periodontal pathogens be studied in an attempt at discovering the association or not between periodontal disease and/or others infections and atherosclerosis, from the presence of these bacteria in atheromas

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The assessment of oral health status in elderly patients is essential for the development of specific health policies. The prevalence of oral diseases is high in this population. The self-perception of oral health conditions influences the demand for oral care and quality of life for seniors. The aim of this study was to assess self-perception of oral health status in 100 elderly of both sexes, aged 60 years or older and functionally independent the Basic Health Unit of Felipe Camarão II, Natal, Brazil. For comparison of self-perception data was collected in Bom Pastor, Natal / RN. In this research data were collected a questionnaire grouped into two parts. The first part with the socio-demographic data, subjective and objective condition of oral health and access to the service, the second part GOHAI Index. This index consists of 12 items that make it possible to obtain information involving aspects of chewing, speech, phonation, and self-assessed oral health. The results were subjected to statistical tests of Mann-Whitney and Kruskal-Wallis test (α = 0.05), to identify possible predictors of self-evaluation. As a result, 69% were female, ages ranged from 60 to 86 years, with a median of 65 years. In relation to marital status 48% were married. For the years of study, the sample had an average of 3 years. For the last visit to the dentist, only 27% of seniors had visited the Dentist for less than a year. Regarding the questions about the presence of gingival and dental problems were answered by 46% and 21% respectively. The data on the perception of your teeth and gums, 44%. The index showed GOHAI value for self-perception of 30 points to Felipe Camarão and 28 points for the Bom Pastor, both considered a low perception. We identified predictors of self-rated number of people in the room, participate in any associational activity, there is problems with your teeth and your gums. Concluded a negative self-perception of oral health condition by Gone in both areas, influenced by socioeconomic and cultural issues, although they realize the importance given to oral health, but by the misfortunes of other prominent favored little valuing of oral health