6 resultados para CdS

em Universidade Federal do Rio Grande do Norte(UFRN)


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In recent years, the area of advanced materials has been considerably, especially when it comes to materials for industrial use, such as is the case with structured porosity of catalysts suitable for catalytic processes. The use of catalysts combined with the fast pyrolysis process is an alternative to the oxygenate production of high added value, because, in addition to increasing the yield and quality of products, allows you to manipulate the selectivity to a product of interest, and therefore allows greater control over the characteristics of the final product. Based on these arguments, in this work were prepared titanium catalysts supported on MCM-41 for use in catalytic pyrolysis of biomass, called elephant grass. The reactions of pyrolysis of biomass were performed in a micro pyrolyzer, Py-5200, coupled to GC / MS, the company CDS Corporation, headquartered in the United States. The catalysts Ti-MCM-41 in different molar ratios were characterized by XRD, TG / DTG, FT-IR, SEM, XRF, UV-visible adsorption of nitrogen and the distribution of particle diameter and specific surface area measurement by the BET method. From the catalytic tests it was observed that the catalysts synthesized showed good results for the pyrolysis reaction.The main products were obtained a higher yield of aldehydes, ketones and furan. It was observed that the best reactivity is a direct function of the ratio Si/Ti, nature and concentration of the active species on mesoporous supports. Among the catalysts Ti-MCM-41 (molar ratio Si / Ti = 25 and 50), the ratio Si / Ti = 25 (400 ° C and 600 ° C) favored the cracking of oxygenates such as acids , aldehydes, ketones, furans and esters. Already the sample ratio Si / Ti = 50 had the highest yield of aromatic oxygenates

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O tema proposto nesta tese vai ao encontro do atual debate em curso no Brasil e no mundo acerca de duas dimensões da cadeia agroalimentar: produção e consumo. Desse modo, as questões de como se dá essa relação frente às estratégias locais por diferentes atores, terá ênfase. Para isso, como campo empírico foram escolhidos três municípios localizados no território Centro-Sul do estado do Paraná: Irati, Inácio Martins e Fernandes Pinheiro que desde 2004 estão inseridos no Programa de Aquisição de Alimentos (PAA), mais especificamente na modalidade Compra com Doação Simultânea (CDS). A hipótese que embasa este estudo é de que o PAA poderá ser capaz de assumir um caráter estruturante - a partir do seu viés pedagógico, capacidade organizativa de produção, manutenção da diversidade ou resgate da policultura (e aqui se privilegia a agroecologia), bem como uma alternativa viável de acesso a um tipo de mercado (mercado institucional) -, não por altruísmo dos atores, mas por ser mais vantajoso ser parte integrante, do que estar à parte do processo, aliando a isso melhorias nas condições alimentares tanto das suas famílias, quanto das entidades receptoras. O objetivo principal foi analisar as relações sociais e as práticas alimentares de um grupo de agricultores(as) agroecológicos entre as responsáveis pelo recebimento dos alimentos doados buscando compreender se o PAA possibilita a Soberania e Segurança Alimentar e Nutricional (SSAN) de grupos sociais (como das famílias rurais) e das pessoas atendidas por estas entidades. A metodologia utilizada foi a de estudo de caso. Como procedimentos foram empregados entrevistas semi-estruturadas e aplicação de questionários como: Escala Brasileira de Insegurança Alimentar(EBIA) e Questionário de Frequência de Consumo Alimentar(QFCA). A amostra foi composta por agricultores(as)/ fornecedores(as) do PAA, nutricionistas e, coordenadora de uma das entidade dos seus produtos é, de fato, o que os mobiliza a continuar produzindo em maior diversidade e quantidade. Após a vivência dos(as) agricultores(as) /fornecedores de estarem inseridos no Programa foi possível para estes atores se sentirem parte do processo e, assim, repensar suas práticas de produção de alimentos, seja ela destinada ao autoconsumo, seja voltada à comercialização. Para além da discussão acerca da produção destinada ao autoconsumo, ficou claro o processo de recampesinização entre as famílias de agricultores(as). O processo de (re)conexão se apresenta de forma frágil, considerando, sobretudo, as considerações feitas pelas mediadoras. Trazer à tona o debate acerca da produção-consumo de alimentos, tanto na perspectiva de quem produz, como na de quem consome, e tomando por referência a operacionalização de políticas públicas, viabiliza a ampliação de debates e a concretização de ações mais contundentes numa perspectiva de minorar a situação de vulnerabilidade (social e alimentar) e de pobreza rural

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Family Health Strategy (FHS), founded in 1994 has appeared to play a strategic role in the SUS construction and consolidation. It has reaffirmed its Principles and Guidelines and has elected family as core of attention. The principle that has guided the work concerns the quality of the relationship between professional and family. Thus, the FHS has the family as a subject of health-disease process, and relations with its own characteristics and can be partners in building their health and improvement of quality of life of its members and the entire community. This study aims to characterize the surgeon-dentist (SD) working process in the family health strategy, from the knowledge of the SD integration with other team members; organization of services; development of shares, changes perceived by SDs, as well as knowing the surgeon-dentist profile who is part of this strategy. The collecting tool used was a semi-structured questionnaire, in which participated 30 professionals. As for profile, most professionals were women, completed the graduation in public university and did not have any training to work by joining the FHS. Almost all have other public or private working ties. They often carry out activities with students, and occasionally do home visits. In relation to team work, in activities such as home visits, school health, community activities, among others, they sometimes seek the cooperation of other members. The way of accessing for users in the most part has occurred through the schedule. The most frequently activities made to the Centro Especialidades Odontológicas (CEO), are in Endodontics and Prosthesis. The majority of them participate in team meetings, but they do not have frequency set to happen. As for the planning and programming of activities to be conducted, most said that individually develops them. Concerning the performance of their duties, most reported being satisfied, but that improvements could happen. Besides, they reported improvements in dental care following the inclusion of SD in the FHS in various aspects, such as access, organization, humanization, care and oral disease prevention. The professionals had poor integration with other team members, in addition to have a profile to more individualistic work, a fact seized by way of development and planning of actions. They work the actions in individual and curative way, in detriment promotion and collective ones. They work humanization, definition of territory and adscript population. Thus, it is concluded that the working process developed by SDs, includes the part which is advocated by FHS. This points out to a greater undertaking of this process aiming to detect the weakness met in order to reach the potential that the FHS represents in organization of basic attention

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The relationship between periodontal and cardiovascular diseases is a reality in the current days. The knowledge about the role of periodontal disease as a risk factor to cardiovascular disease from dentistry and physicians is very important to try to eliminate this risk factor. The aim of this work was to investigate, using a questionary, if physicians and dentistry are aware about this relationship and if they think that it is important. These forms were distributed in 4 groups: cardiologists (n=90), physicians from other specialist (POS) (n=110), periodontists (n=35) and dentistry from other specialist (DOE) (n=85). We had a loss off 32,4% of the total sample due to a lack of response of some professionals. Our results showed that all cardiologists, all dentists and 68,2% of POE said that they had gotten information about the relationship between periodontal and cardiovascular disease, and just 6 POS don t believe that this relationship can occur. When questioned if, even when a periodontal disease is diagnosed, there is a habit to treat or orient the patient for treatment, 29,5% of cardiologists answered no, 25,5% of POE also answered that they did not orient and only 1 DOE answered that he did not treat nor orient. All periodontists said that treat their patients when periodontal disease was identify. The physicians seem not to find important the relationship that exist between periodontal and cardiovascular diseases and the dentistry have shown a good knowledge about this subject. Maybe, if physicians and dentistry work together, the incidence of cardiovascular disease decreases

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Receptor ativador nuclear κappa B (RANK), ligante do receptor ativador nuclear κappa B (RANKL) e osteoprotegerina (OPG) são membros da família do fator de necrose tumoral relacionados com o metabolismo ósseo. A formação, diferenciação e atividade dos osteoclastos são reguladas por estas três proteínas. RANK é um receptor transmembrana presente em diversos tipos celulares, principalmente em células de linhagem macrofágica, linfócitos, células dendríticas e fibroblastos e quando ativado pelo seu ligante, RANKL, promove a diferenciação e ativação de células osteoclásticas responsáveis pelo processo de reabsorção óssea. A OPG impede a ligação RANK/RANKL atuando como um receptor inibitório para a atividade osteolítica. O objetivo deste estudo foi comparar a expressão imuno-histoquímica destes biomarcadores em cistos radiculares (n=20) e cistos dentígeros (n=20). A expressão imuno-histoquímica destes marcadores foi avaliada no epitélio e na cápsula dos cistos por escores e percentuais médios de imunomarcação. Para o epitélio, a análise semi-quantitativa revelou um padrão similar dos escores de imunomarcação de RANK, RANKL e OPG nas lesões, não havendo diferença estatística significante (p=0.589, p=0.688, p=0.709, respectivamente). Para a cápsula cística a análise quantitativa, mostrou diferença estatística significante entre os percentuais médios de imunomarcação do RANK e RANKL (p=0,001 e p=0,005, respectivamente) nos cistos. A correlação dos escores de imunomarcação de RANKL e OPG no epitélio do CR e do CD revelou diferença estatística significante (p=0,029, p=0,003, respectivamente). No epitélio dos CRs e dos CDs observou-se uma maior imunoexpressão da OPG comparada a do RANKL. Os resultados apontam a presença de RANK, RANKL e OPG nos cistos radiculares e cistos dentígeros, sugerindo a atuação destas proteínas no desenvolvimento e expansão das lesões no osso adjacente

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The radicular cysts (RCs) and dentigerous (DCs), despite having different etiologies, form a pathological cavity lined by epithelium, which grows due to the buildup of fluid inside, as the surrounding bone is reabsorbed and the epithelium will being induced to proliferate. The epithelial proliferation, which has been identified as one of the key processes in the growth of odontogenic cystic lesions, is influenced by growth factors such as EGFR (epidermal growth receptor factor) and podoplanin (PDPN), many of which may have its production stimulated mainly during inflammatory processes. The objective of this research was to evaluate and compare the immunohistochemical expression of EGFR and PDPN in 30 cases of RCs and 30 cases of DCs, semiquantitatively, in light microscopy, associating it with the degree of inflammation, cellular localization of immunostaining and with the immunostained epithelial layers. Data were statistically analyzed by Chi-square test and Fisher exact test, considering a significance level of 5 %. The results showed high immunoreactivity of both proteins in the lesions studied, only statistically significant difference was observed in immunostaining of PDPN (p=0.033), which proved higher in RCs. The other analyzed parameters showed no relevant significant differences. We conclude that, as EGFR and PDPN showed high immunoreactivity in cystic lesions analyzed, these proteins participate the pathogenesis of these lesions through the epithelial stimulation process, despite having different etiologies. Furthermore, it can infer that the higher immunostaining of PDNP in RCs that DCs showed no distinction indicator between the two lesions, regarding their etiologies, once this protein also showed a considerable expression in DCs, independent of the intensity of the inflammatory infiltrate