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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

O sistema ?nico de sa?de e o princ?pio da sustentabilidade : interconex?es e perspectivas acerca da prote??o constitucional da sa?de

Figueiredo, Mariana Filchtiner 27 March 2013 (has links)
Made available in DSpace on 2015-04-14T14:34:01Z (GMT). No. of bitstreams: 1 449234.pdf: 220784 bytes, checksum: 09b94141e1430362b0f4f8e6a6a0eba6 (MD5) Previous issue date: 2013-03-27 / This study aims to examine Brazilian healthcare system (so-called Sistema ?nico de Sa?de, or simply SUS) regarding the efficacy of sustainability principle, focusing on interconnections and perspectives to health constitutional protection. In its first part, the text presents a study of SUS and the fundamental right to health, according to Brazilian constitutional and legal frame. Since review and criticism to previous models of healthcare, the text analyses the process of constitutionalization and implementation of SUS, particularly the efficacy and effectiveness of principles that structure SUS, as well as the efficacy and effectiveness of the fundamental right to health. Passing to its second part, the text is initially devoted to investigate sustainability principle, its historical context and most common theoretical definitions, in order to affirm its normative and legal nature, as well as its effectiveness as a constitutional-based principle under Brazilian law. This fact allows the recognition of an objective dimension for sustainability principle, from which different legal effects can be developed and affirmed. The text explores, then, sustainability principle s efficacy concerning the SUS, critically examining the current model of healthcare, in order to point out problems and possible alternatives towards the effectiveness of constitutional principles that structure SUS, as a way to increase the conditions for health protection and promotion, as premises to a life with dignity and quality / Este trabalho tem por objeto examinar o Sistema ?nico de Sa?de (SUS) a partir da incid?ncia do princ?pio da sustentabilidade, com foco nas interconex?es e perspectivas que da? exsurgem para a prote??o constitucional da sa?de. A primeira parte do texto ? dedicada ao estudo do Sistema ?nico de Sa?de (SUS) e do direito ? sa?de no marco constitucional brasileiro. A partir da investiga??o e cr?tica dos modelos anteriores de assist?ncia ? sa?de, s?o analisados o processo de constitucionaliza??o e implementa??o do SUS, especialmente no que respeita ? efic?cia dos princ?pios que o estruturam, bem como a efic?cia jur?dica do direito fundamental ? sa?de. A segunda parte do trabalho ? inicialmente voltada para o estudo do princ?pio da sustentabilidade, sua contextualiza??o hist?rica e defini??es te?ricas mais comuns, concluindo-se pela afirma??o de sua natureza jur?diconormativa e vig?ncia, na condi??o de princ?pio albergado pelo sistema constitucional brasileiro, a permitir o reconhecimento de uma especial dimens?o objetiva da? decorrente, ensejadora de efeitos jur?dicos diversos. O texto explora ent?o a efic?cia jur?dica do princ?pio da sustentabilidade sobre o SUS, examinando criticamente o atual modelo de assist?ncia ? sa?de, para apontar problemas e indicar poss?veis alternativas voltadas ? realiza??o dos princ?pios constitucionais que estruturam o SUS e, enfim, ao incremento das condi??es de prote??o e promo??o da sa?de, como pressupostos de uma vida digna e com qualidade
62

Estudos do uso da citocinina BAP e do gongocomposto na estaquia da Pitaieira (Hylocereus undatus) / Studies of the use of cytokinin BAP and millipede-compost on Pitaia (Hylocereus undatus) propagated by cuttings

CRUVINEL, F?bio Ferreira 21 February 2017 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-02-20T18:25:57Z No. of bitstreams: 1 2017 - F?bio Ferreira Cruvinel.pdf: 1438823 bytes, checksum: 49768f1c89baea668d06d925b16c5e0c (MD5) / Made available in DSpace on 2018-02-20T18:25:57Z (GMT). No. of bitstreams: 1 2017 - F?bio Ferreira Cruvinel.pdf: 1438823 bytes, checksum: 49768f1c89baea668d06d925b16c5e0c (MD5) Previous issue date: 2017-02-21 / CAPES / The pitaya (Hylocereus undatus (Haw.) Britton & Rose) has an exotic shape, pleasant taste, easy digestibility and antioxidant properties, which have given greater demands in the Brazilian market for this fruit in recent years. The production of seedlings is a determining factor for the successful installation of pitaias orchards and the use of phytoregulators such as BAP (6-benzylaminopurine) and organic substrates, such as millipede-compost, in the production of seedlings of this fruit is still little reported. The objective of this work was to analyze the effect of BAP and millipede-compost on the production of pitaia seedlings. Pitaia cuttings from Fazendinha Agroecol?gica - Km 47, in the town of Serop?dica-RJ, were used. The stakes were standardized with 20 cm in length. The experiment with the phytoregulator was conducted in the greenhouse sector of the UFRRJ and the cuttings planted in substrate composed of sand and bovine manure in a ratio of 1: 1 by volume in a completely randomized design (DIC) in a factorial scheme (2X4) with 4 replicates: (2) By immersion and incision made at the apex of cladodes stakes versus (4) four doses of BAP (0, 50, 100 and 150 mg.L-1) were applied. Non-destructive Growth Analysis was performed and the simple correlations were calculated with the climatic data obtained at the Ecologia Automatic Station in Serop?dica-RJ. For the experiment with the millipede compost, the cutting was conducted in pots with three types of substrates: Gongocomposto, Biomix? and sand + bovine manure (1: 1 by volume) in DIC with five replicates. The results showed a linear tendency in number of shoots and quadratic tendency in other parameters (length, fresh and dry weight) evaluated with use of BAP. There was a correlation between the growth rates of the pitaya with the data of Global Solar Radiation of the 19h (22h UTC) period. The use of the gongocomposto showed larger and more vigorous plants of pitaia. / O fruto da pitaieira (Hylocereus undatus (Haw.) Britton & Rose) apresenta forma ex?tica, sabor agrad?vel, f?cil digestibilidade e propriedades antioxidantes, caracter?sticas essas que proporcionaram maiores demandas no mercado brasileiro por essa fruta nos ?ltimos anos. A produ??o de mudas ? um fator determinante para o sucesso da instala??o de pomares de pitaias e o uso de fitorreguladores como o BAP (6-benzilaminopurina) e substratos org?nicos, como o gongocomposto, na produ??o de mudas desta frut?fera ainda ? pouco relatado. O objetivo deste trabalho foi analisar o efeito do BAP e gongocomposto na produ??o de mudas de pitaia. Utilizaram-se estacas de pitaieira proveniente da Fazendinha Agroecol?gica ? Km 47, no munic?pio de Serop?dica-RJ. As estacas foram padronizadas com 20 cm de comprimento. O experimento com o fitorregulador foi conduzido no setor de olericultura da UFRRJ, em casa de vegeta??o e as estacas plantadas em substrato composto por areia e esterco bovino na propor??o 1:1 em volume em Delineamento Inteiramente Casualizado (DIC), com 4 repeti??es, em esquema fatorial (2X4), sendo (2) por imers?o e incis?o feita no ?pice das estacas dos clad?dios versus (4) quatro doses da citocinina BAP (0, 50, 100 e 150 mg.L-1). Foi realizada a An?lise de Crescimento n?o destrutiva e foram calculadas as correla??es simples com os dados clim?ticos obtidos na Esta??o Autom?tica Ecologia em Serop?dica-RJ. Para o experimento com o gongocomposto a estaquia foi conduzida em vasos com tr?s tipos de substratos: Gongocomposto, Biomix? e areia+esterco bovino (1:1 em volume) em DIC com cinco repeti??es. Os resultados mostraram uma tend?ncia linear positiva no n?mero de brota??es e quadr?tica para o incremento de comprimento, peso fresco e seco das brota??es para o uso da citocinina BAP no incremento de. Houve correla??o entre as taxas de crescimento da pitaia com os dados de Radia??o Solar Global do per?odo das 19h (22h UTC). O uso do gongocomposto proporcionou maiores e mais vigorosas mudas de pitaieira.
63

POSTMINIMALIST CHORAL MUSIC: A PEDAGOGICAL PERSPECTIVE

Chai, Joshua John 01 January 2019 (has links)
After the strict processes of mid-twentieth-century minimalism, a new musical style has emerged which retains extensive use of repetition, but is generally more aurally accessible, based in non-functional triadic harmony, and flexible in its compositional structure. Frequent use of non-minimalist resources, musical resources from multiple styles in a single composition, and quotation from previous historical periods define this flexibility. American choral music has many popular compositions that exhibit characteristics of this new musical style, in part because of its accessibility relative to earlier minimalist styles, and in part because it adapts easily to the choral setting. At the same time, teaching this music to choirs requires resources that are not in standard-practice choral pedagogy textbooks or peer-reviewed choral journals. This monograph utilizes newer research in musical analysis and several recent writings attempting to generalize the postminimalist style to develop a definition of choral postminimalism. Then, this monograph also suggests analytical approaches and resources for choral warm-ups, score preparation, and other pedagogical tools for three pieces: Arvo Pärt’s The Beatitudes, Nico Muhly’s Bright Mass with Canons, and Tarik O’Regan’s The Ecstasies Above.
64

Creaci?n de un plan de negocios para la implementaci?n de un sistema de pagos electr?nicos m?viles

Z?rate Arellano, Rodrigo Daniel January 2014 (has links)
Tesis para optar al grado de Mag?ster en Gesti?n para la Globalizaci?n / En el presente informe se describe un modelo de negocios para el desarrollo de soluciones de pago m?viles en formato prepago cerrado. La idea de negocio se basa en la alta penetraci?n de los servicios de telefon?a m?vil en el pa?s (SUBSECRETAR?A DE TELECOMUNICACIONES, 2012) y el efecto que puede causar para aumentar los ?ndices de inclusi?n financiera (MESA DE TRABAJO DE LA AGENDA DE IMPULSO COMPETITIVO, 2013). Junto a ello, y de acuerdo a datos del Banco Mundial, hay un alto inter?s entre la poblaci?n por contar con medios de pago m?vil electr?nico e integrar servicios a trav?s del celular. El entorno de mercado es propicio, dada la virtual inexistencia de proveedores de medios de pago electr?nicos alternativos a Transbank, que opera principalmente como apoyo a las instituciones bancarias; en tanto, las soluciones m?viles actuales consisten b?sicamente en servicios de M-Banking (acceso a la cuenta electr?nica a trav?s de internet m?vil). La oportunidad de negocios descrita en este informe se basa en estos antecedentes y aprovecha la ventaja tecnol?gica que pueden proveer los productos de la compa??a multinacional Watchdata. Su soluci?n SIMpass es una innovaci?n en el mundo de los dispositivos de pago m?vil, ya que permite transformar a cualquier tel?fono celular en un dispositivo de pagos m?viles, s?lo instalando la nueva tarjeta SIM. Se ha caracterizado el mercado de los medios de pago electr?nico en Chile, identificando los actores principales y las alternativas de soluci?n t?cnica, incluyendo un an?lisis de los factores pol?ticos, econ?micos, sociales, ambientales y sociales (PESTEL, por su sigla en ingl?s). El modelo de negocios entonces corresponde a el establecimiento de un sistema de pagos m?viles, utilizando la tecnolog?a desarrollada por Watchdata, que trabajar? en un modelo de dos lados, realizando asociaciones con operadores m?viles virtuales por un lado y con compa??as de retail por el otro, permitiendo la entrega de un servicio diferenciado a los clientes finales que produzca beneficios para ambas partes. El negocio recibir? entradas por la entrega y puesta en marcha del servicio a ambos clientes corporativos y adem?s a trav?s de una comisi?n por transacci?n que se cobrar? a los usuarios finales. El modelo de negocio se describe usando la metodolog?a Canvas. El resultado del plan de negocios es la definici?n de una estrategia de negocios y una estructura organizacional para la prestaci?n del servicio de pagos m?viles. Se realiza una evaluaci?n financiera considerando los costos en ingresos proyectados dados los supuestos de mercado, cuyo resultado es un VAN de US$1.700.000 al final del tercer a?o de operaci?n, con una tasa interna de retorno del proyecto de 70%. Finalmente se realiza un an?lisis de posibilidades futuras de expansi?n, dependiendo de la evoluci?n del mercado y su regulaci?n.
65

Modelagem e simula??o de um sistema de bombeio mec?nico em po?os direcionais utilizando par?metros concentrados

Lins, Filipe Campos de Alcantara 07 May 2010 (has links)
Made available in DSpace on 2014-12-17T14:08:44Z (GMT). No. of bitstreams: 1 FilipeCAL_DISSERT.pdf: 1482396 bytes, checksum: ac4b807c36f7a7406c75156b433df756 (MD5) Previous issue date: 2010-05-07 / This work aims presenting the development of a model and computer simulation of a sucker rod pumping system. This system take into account the well geometry, the flow through the tubing, the dynamic behavior of the rod string and the use of a induction motor model. The rod string were modeled using concentrated parameters, allowing the use of ordinary differential equations systems to simulate it s behavior / Este trabalho visa apresentar a modelagem e a simula??o computacional de um sistema de eleva??o de petr?leo por bombeio mec?nico. Tal sistema leva em considera??o a geometria do po?o, o escoamento do fluido na coluna de produ??o, o comportamento din?mico da coluna de hastes e o uso de um modelo para o motor de indu??o. A coluna de hastes foi modelada de forma a utilizar par?metros concentrados, permitindo o uso de sistemas de equa??es diferenciais ordin?rias na simula??o do comportamento da mesma
66

Fatores que afetam a competitividade na produ??o de hortali?as org?nicas no Estado do Rio Grande do Norte / Factors affecting the competitiveness the production of organics vegetables in the state of Rio Grande do Norte

Tacconi Neto, Ernesto Alexandre 19 May 2006 (has links)
Made available in DSpace on 2014-12-17T14:52:34Z (GMT). No. of bitstreams: 1 ErnestoATN.pdf: 2867586 bytes, checksum: 365968b169b7f677e1d1f4d8af8d3fab (MD5) Previous issue date: 2006-05-19 / The Brazilian organic market has growing year by year, and this commercialization is extremely important to the country, because it allows a bigger preoccupation with the environmental preservation, as well as to create employments and income to the rural workers. However, is necessary that these producers define forms of competition in the market, the way how they will compete, focusing aspects that really matters to the clients. So, the work objective is investigate, based in the rural producers perceptions, the facts which affect the competition the production of organics vegetables in the state of Rio Grande do Norte. With the aim of contribute to the made of strategic decisions related to the production and commercialization of these products in the agriculture scenery norte-rio-grandense, besides to contribute with information about the competition, helping as reference to others important researches. In the methodological view, this study can be qualified as an applied research study, with descriptive objective and quantitative approach. The instrument used was the formulary, resuming to producers of organics products in Rio Grande do Norte state, that grows the segment of organic types of vegetables and greens, been thirty two producers. The data was treated through of the descriptive analyze and the Cluster s analyze. The descriptive research results indicate that the main factors which affect the competition of the organics products in our State are the cost, the diversification and reliability. The Cluster s analyze shows that exists am group of organics producers who uses frequently a specialized technique and they give support to the bigger retail market, as supermarkets / O mercado org?nico brasileiro vem crescendo a cada ano, e essa comercializa??o ? extremamente importante para o pa?s, pois possibilita uma maior preocupa??o com a preserva??o ambiental, al?m de gerar emprego e renda para os trabalhadores rurais. Para tanto, ? necess?rio que esses produtores definam formas de competir no mercado, focalizando os aspectos que realmente importam para os clientes. Portanto, o objetivo deste trabalho ? investigar, com base na percep??o dos produtores rurais, os fatores que afetam a competitividade na produ??o de hortali?as org?nicas no Estado do Rio Grande do Norte, com a finalidade de contribuir para a tomada de decis?es estrat?gicas no que diz respeito ? produ??o e comercializa??o no cen?rio agr?cola norte-rio-grandense, al?m de disponibilizar informa??es sobre a competitividade desses produtos, a fim de servir de refer?ncia para outras pesquisas que sejam pertinentes. Do ponto de vista metodol?gico, o presente trabalho pode ser classificado como um estudo de pesquisa aplicada, com objetivo descritivo e abordagem quantitativa. O instrumento utilizado foi o formul?rio, delimitando-se a pesquisar os produtores de produtos org?nicos do Estado Rio Grande do Norte, que cultivam o segmento do tipo legumes e verduras org?nicas, totalizando trinta e dois produtores. Os dados foram tratados atrav?s da An?lise Descritiva e da An?lise de Cluster. Resultados da pesquisa descritiva indicaram que os principais fatores que afetam a competitividade dos produtos org?nicos no Estado do Rio Grande do Norte s?o os custos, a diferencia??o e a confiabilidade. A an?lise de Cluster apresentou que existe um agrupamento de produtores org?nicos que utilizam com maior freq??ncia ? ajuda de t?cnico especializado e este mesmo grupo ? o que atende ao ramo varejista de maior porte, como supermercados
67

Fun??o compras no setor p?blico: fatores preponderantes para o alcance da celeridade dos preg?es eletr?nicos da Base A?rea de Natal

Almeida, Alessandro Anibal Martins de 18 March 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-16T23:16:37Z No. of bitstreams: 1 AlessandroAnibalMartinsDeAlmeida_DISSERT.pdf: 1657763 bytes, checksum: 6db22b702082732061a8789cd23c535a (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-24T20:54:28Z (GMT) No. of bitstreams: 1 AlessandroAnibalMartinsDeAlmeida_DISSERT.pdf: 1657763 bytes, checksum: 6db22b702082732061a8789cd23c535a (MD5) / Made available in DSpace on 2016-08-24T20:54:28Z (GMT). No. of bitstreams: 1 AlessandroAnibalMartinsDeAlmeida_DISSERT.pdf: 1657763 bytes, checksum: 6db22b702082732061a8789cd23c535a (MD5) Previous issue date: 2016-03-18 / O presente estudo discute a quest?o dos prazos nos processos de compras no ?mbito da Administra??o P?blica Federal. Seu principal objetivo ? analisar os fatores que influenciaram, preponderantemente, na execu??o das subfases do preg?o eletr?nico na BANT, no ano de 2014, quanto ao atendimento ao princ?pio da celeridade. A pesquisa ? do tipo descritiva, uma vez que identifica e analisa os fatores que influenciaram nos prazos das compras, por meio da observa??o direta e de entrevistas. Com base no referencial te?rico, a fun??o compras, estabelece quatro dimens?es de an?lise: ?Legisla??o e processos de compras?, ?Estrutura e Organiza??o do setor de compras?, ?Sistemas de compras? e ?Recursos humanos do setor de compras?. As an?lises demonstraram que, diferentemente do que ocorre no ?mbito privado, o setor de compras p?blico n?o alcan?ou um status estrat?gico dentro das organiza??es, o que traz consequ?ncias prejudiciais ? celeridade das compras. Com isso,verificou que h? a necessidade de uma maior participa??o do pessoal do setor de compras e dos pregoeiros na formula??o das estrat?gias de aquisi??o da organiza??o e que esses elementos de compras apresentam, em suas atitudes, um perfil h?brido, proativo quanto ?s especifica??es dos itens, mas reativo em rela??o ? necessidade de compras de car?ter de urg?ncia, fruto da car?ncia de um melhor planejamento, o que sobrecarrega o trabalho do setor. A observa??o desses aspectos estrat?gicos da fun??o compras na BANT influenciou na constata??o de que a car?ncia de pessoal e de investimentos em qualifica??o somados ao excesso de rigor e formalismo da legisla??o, entre outros fatores, contribu?ram, preponderantemente, para a falta de celeridade dos processos. Por fim, este estudo traz sugest?es para o aumento da celeridade das compras da BANT. / This study discusses the issue of deadlines in the purchasing process within the Federal Public Administration. Your main goal is to analyze the main factors that influenced, mainly in the implementation of sub-phases of electronic trading in BANT, in 2014, as service to the principle of celerity. The research is descriptive since they were identified and analyzed the factors that influenced in terms of purchases, through direct observation and interviews. Based on the theoretical framework, the purchasing function, four dimensions of analysis were established: "Legislation and procurement processes", "Structure and Organization of the purchasing department", "purchasing systems" and "Human Resources of the purchasing department." Analysis showed that, unlike what happens in the private sector, the public procurement sector has not reached a strategic status within organizations, which brings harmful consequences to the speed of the purchases. It was found that there is a need for greater involvement of the purchasing department staff and criers in the formulation of the organization's purchasing strategies and that these purchases elements present, about their attitudes, a hybrid profile, proactive regarding specifications of the items, but reactive in relation to the need to urgently purchase, due to the lack of a better plan, which overloads the work of the sector. The observation of these strategic aspects of the procurement function in BANT influenced the finding that the lack of staff and expertise in investments plus the lack of rigor and formality of legislation, among other factors, contributed mainly to the lack of speed of processes.
68

Comportamento mec?nico e tenacidade ? fratura de ligas de alum?nio 2024 e 7075 submetidas a diferentes tempos de envelhecimento

Cavalcante, Felipe Fernandes 06 May 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-26T23:06:54Z No. of bitstreams: 1 FelipeFernandesCavalcante_DISSERT.pdf: 15830059 bytes, checksum: 1df43f246bc497f6fb2c86ad9f43fb04 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-30T22:45:53Z (GMT) No. of bitstreams: 1 FelipeFernandesCavalcante_DISSERT.pdf: 15830059 bytes, checksum: 1df43f246bc497f6fb2c86ad9f43fb04 (MD5) / Made available in DSpace on 2016-08-30T22:45:53Z (GMT). No. of bitstreams: 1 FelipeFernandesCavalcante_DISSERT.pdf: 15830059 bytes, checksum: 1df43f246bc497f6fb2c86ad9f43fb04 (MD5) Previous issue date: 2016-05-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Sabe-se que a grande parte das ligas de alum?nio pode sofrer varia??es significativas em suas propriedades mec?nicas dependendo do tratamento de envelhecimento realizado. Por?m, poucos trabalhos apontam as caracter?sticas dessas ligas em condi??es subenvelhecidas e superenvelhecidas, principalmente em rela??o ? tenacidade ? fratura. Al?m disso, estudos recentes apontam que algumas ligas de alum?nio subenvelhecidas podem sofrer uma esp?cie de auto cura, ou seja, esses materiais podem, quando solicitados devido a algum esfor?o externo, tender a um fechamento de algum defeito como uma trinca devido ? precipita??o din?mica, o que aumentaria sua capacidade de resistir ?s solicita??es. Neste contexto, neste trabalho ? avaliada a rela??o entre a tenacidade ? fratura e a resist?ncia ? tra??o e as condi??es de tratamentos t?rmicos de duas ligas de alum?nio (2024-T351 e 7075-T651), tanto na condi??o de entrega quanto submetidas a tratamentos t?rmicos de solubiliza??o (a 480 0C por 2,5 h) e envelhecimento artificial (145 0C por 8, 10, 16 e 24 h para a 7075, e 190 0C por 1, 3, 5, 8 e 12 h para a 2024), portanto, em condi??es de subenvelhecimento (abaixo do m?ximo de dureza), envelhecida (no ponto de m?xima dureza) e superenvelhecimento (al?m do ponto de m?xima dureza). Os materiais, nestas diferentes condi??es de processamento foram caracterizados do ponto de vista mec?nico - atrav?s dos ensaios de tenacidade ? fratura, utilizando a metodologia de entalhe chevron - KICVM (ASTM 1304), de tra??o uniaxial (ASTM E8M) e dureza HRB (ASTM E18) - e do ponto de vista estrutural, atrav?s da microscopia ?ptica, MEV e EDS. As microestruturas obtidas nas diferentes condi??es s?o avaliadas por MEV e DR-X. Os micromecanismos de fratura das amostras de tra??o e tenacidade ? fratura s?o avaliados por MEV. Em rela??o ? dureza verificou-se, para ambas as ligas, que ouve apenas um pequena tend?ncia de redu??o dos valores obtidos para a amostras envelhecidas em rela??o ao estado de entrega. Os resultados dos ensaios de tra??o indicam tamb?m uma pequena redu??o da resist?ncia das amostras envelhecidas, em rela??o ao estado de entrega. Estes resultados de dureza e tra??o indicam que a m?xima resist?ncia pode ser obtida para tratamentos de envelhecimento por 5 h (2024) e entre 10 e 12 h (7075). Os resultados de tenacidade ? fratura mostram que n?o houve influ?ncia significativa dos tempos de envelhecimento de 8h, 10h, 16h e 24h sobre os valores de KICV para a liga 7075, apesar dos tratamentos de envelhecimento terem aumentado a tenacidade ? fratura em rela??o ao estado de entrega. Em rela??o ? liga 2024, nem todos os resultados de tenacidade ? fratura puderam ser validados em fun??o da trajet?ria de crescimento de trinca fora do regime de abertura (modo I), mesmo para corpos de prova de maiores dimens?es. Este resultado indica que os diferentes tratamentos de envelhecimento da liga 2024 atuaram no sentido de aumentar a tenacidade do material, elevando a amplitude dos eventos inel?sticos ? frente da trinca. / Heat treatable aluminum alloys may experience significant changes in mechanical properties depending on heat treatment developed. Futhermore, a few works discuss about this properties in underaged and overaged conditions, mainly about fracture toughness. Recently, some researches showed that some aluminum alloys in underaged conditions may indicate the self healing phenomenon, in other words, when streched mechanically, the material could present a closure, or a reduction in crack growth ratio due local compressive stress associated to dynamic precipitation. In this context, its valued the relationship between fracture toughness, mechanical properties and heat treatment in two aluminum alloys (2024-T351 e 7075-T651) when submitted to solubilization (480 ?C for 2,5h) and artificial aging (145 ?C for 8h, 10h, 12h, 16h and 24h for 2024-S1 named first set and 7075; and 190 ?C for 1h, 3h, 5h, 8h and 12h for 2024-S2, second set), obtaining underaged, peak hardness and overaged conditions. The samples were featured using fracture toughness tests with a chevron notch, K??? (ASTM E1304); tensile tests (ASTM E8/E8M) and Vickers hardness (ASTM E 384). In structural aspects, this alloys were featured using optical microscopy and scanning electron microscopy (SEM), in microstructural aspects, using energy-dispersive X-ray spectroscopy (EDS). The micromechanisms of fracture surface on chevron samples are showed using SEM. After results, hardness and ultimate tensile stress showed maximum values between 3h and 5h (2024-S2) and approximately 10h and 12h (7075). About 2024-S2 alloy, it is showed the phenomenon of dynamic precipitation in delivery state, underaged and peak aged samples, due little peaks on stress-strain curves. However, in 2024 first and second sets, all results cannot be valid because the samples showed a significant change in fracture mode presenting a mix of mode I + mode II, futhermore, thickness B is not sufficient for attend ASTM E 1304. The 7075 aluminum alloy presented a distinguished behavior, showing independence in properties like fracture toughness and hadness mainly in overaged conditions, because as the hardness value increase in this condition, fracture toughness increased also. Besides that, K??? values showed no much variation besides the different times of aging, despite this values are much high than delivery state condition. About micromechanisms of fracture, all conditions presented dimples, and cleavage fracture associated to coarse precipitates.
69

An?lise da composi??o qu?mica, atividade citot?xica e inibi??o de citocinas in vitro de prepara??es de partes a?reas da planta ageratum fastigiatum

Freitas, Beth?nia Alves de Avelar 13 September 2013 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-17T15:38:43Z No. of bitstreams: 2 bethania_alves_avelar_freitas.pdf: 67938565 bytes, checksum: 4f06416afedd4040fb61d7bad494c673 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-17T15:40:36Z (GMT) No. of bitstreams: 2 bethania_alves_avelar_freitas.pdf: 67938565 bytes, checksum: 4f06416afedd4040fb61d7bad494c673 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-17T15:41:09Z (GMT) No. of bitstreams: 2 bethania_alves_avelar_freitas.pdf: 67938565 bytes, checksum: 4f06416afedd4040fb61d7bad494c673 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Made available in DSpace on 2014-12-17T15:41:09Z (GMT). No. of bitstreams: 2 bethania_alves_avelar_freitas.pdf: 67938565 bytes, checksum: 4f06416afedd4040fb61d7bad494c673 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) Previous issue date: 2013 / Ageratum fastigiatum ? uma planta utilizada na medicina popular como anti-inflamat?rio e analg?sico, no entanto, poucos estudos foram realizados a fim de detalhar os mecanismos envolvidos nessa atividade. O objetivo deste estudo foi avaliar a atividade anti-inflamat?ria in vitro do ?leo essencial e do extrato dicloromet?nico de A. fastigiatum. Pela t?cnica de exclus?o do azul de tripam por citometria de fluxo foram determinadas concentra??es n?o t?xicas das prepara??es de A. fastigiatum. As concentra??es n?o t?xicas do ?leo essencial foram 5x10-3 e 1x10-2 ?L/mL. Essas concentra??es foram utilizadas para a pesquisa do potencial anti-inflamat?rio do ?leo essencial, medido por meio da an?lise do perfil de citocinas pro (TNF- ? e IFN- ?) e anti-inflamat?rias (IL-10), em culturas de leuc?citos humanos estimulados e n?o estimulados com PMA (acetato de forbol miristato) . Os dados demonstraram que ambas as concentra??es inibiram o percentual de linf?citos-TNF+ nas culturas estimuladas com PMA. A an?lise cromatogr?fica em fase gasosa acoplada a espectrometria de massas (CG/EM) revelou como principais constituintes no ?leo essencial as subst?ncias ?-pineno (7,51%), limoneno (5,9%), ?xido de cariofileno (13,59%), 1,2 ep?xido humuleno (8,41%) e 1,6-humulanodien-3-ol (17,71%). O extrato dicloromet?nico de A. fastigiatum, na concentra??o 20 ?g/mL, n?o apresentou toxicidade aos leuc?citos do sangue perif?rico humano e reduziu o percentual de linf?citos-TNF-?+ e linf?citos-IFN-?+ nas culturas estimuladas com o PMA. Este extrato foi fracionado em coluna de Sephadex LH-20 (150 g). Na an?lise de citocinas, a fra??o 10 (AFDM 10), na concentra??o 10 ?g/mL, demonstrou efeito anti-inflamat?rio in vitro reduzindo a frequ?ncia de linf?citos-TNF-?+ e a prolifera??o de linf?citos estimulados com PHA (fitohemaglutinina). Sugere-se que parte da atividade anti-inflamat?ria de A. fastigiatum se d? pela inibi??o que os constituintes da planta promovem sobre a ativa??o de leuc?citos. / Tese (Doutorado) ? Programa Multic?ntrico de P?s-Gradua??o em Ci?ncias Fisiol?gicas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013. / ABSTRACT Ageratum fastigiatum is a plant used in folk medicine as topical anti-inflammatory and analgesic agent. However, few studies have been conducted with this plant in order to detail the molecular mechanisms involved in its biological activities. Therefore, main purpose of the present study was to investigate the anti-inflammatory activity of the essential oil and leaf rinse dichloromethane of A. fastigiatum extract. The cytotoxicity of the compounds was assessed by means of trypan blue exclusion. The essential oil at 5x10-3 e 1x10-2 ?L/ did not present cytotoxic activity. These two concentrations were used for investigating the anti-inflammatory potential of the essential oil, by analyzing the pro-inflammatory (TNF-? and IFN-?) and anti-inflammatory (IL-10) cytokine profiles on human leukocyte cultures stimulated and non-stimulated with PMA (phorbol myristate acetate). The data obtained by flow cytometry demonstrated that both concentrations decreased the percentage of lymphocytes ?TNF-? + on the cell cultures stimulated with PMA. In the non-stimulated cell cultures there were no changes in the percentage of IL-10+ cells. The gas phase chromatography coupled with mass spectrometry analysis (GC/MS) revealed that the main compounds present in oil samples were: ?-pinene (7.51%), limonene (5.9%), caryophyllene oxide (13.59%), 1,2 humulene epoxide (8.41%) and 1,6-humulanodien-3-ol (17.71%). The dichloromethane extract of A. fastigiatum, obtained from the washing leaves, at the concentration 20 ?g/mL, did not presented cytotoxicic action on the human peripheral blood leukocytes. Following the same protocol performed to cytokines analysis used before, we observed that the dichloromethane A. fastigiatum extract also decreased the percentage of lymphocytes-TNF-? + and IFN-?+ on the cell cultures stimulated with PMA. This extract after fractionated on Sephadex LH-20 . The dichloromethane A. fastigiatum fraction (AFDM 10) at 10 ?g/mL reducing the frequency of lymphocytes-TNF-?+. Furthermore AFDM 10 decreasing the proliferation of lymphocytes stimulated with PHA (phytohemagglutinin). It is concluded that part of the anti-inflammatory activity of A. fastigiatum is give by inhibiting the plant constituents on promoting the activation of leukocytes.
70

Resist?ncia adesiva ? microtra??o de restaura??es biol?gicas posteriores / Bond strength of biological restorations submitted to microtraction

Nogueira, Lilian Capanema 25 February 2014 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-22T11:43:42Z No. of bitstreams: 2 lilian_capanema_nogueira.pdf: 2184946 bytes, checksum: 6f6169ea092a767b716bac691cf179f3 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-22T11:44:14Z (GMT) No. of bitstreams: 2 lilian_capanema_nogueira.pdf: 2184946 bytes, checksum: 6f6169ea092a767b716bac691cf179f3 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2014-12-22T11:44:31Z (GMT) No. of bitstreams: 2 lilian_capanema_nogueira.pdf: 2184946 bytes, checksum: 6f6169ea092a767b716bac691cf179f3 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2014-12-22T11:44:31Z (GMT). No. of bitstreams: 2 lilian_capanema_nogueira.pdf: 2184946 bytes, checksum: 6f6169ea092a767b716bac691cf179f3 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2014 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / A ?Restaura??o Biol?gica? ? uma t?cnica que pode oferecer uma excelente biocompatibilidade, desgaste fisiol?gico e mant?m as caracter?sticas est?ticas e funcionais da estrutura do dente tais como brilho de superf?cie, textura, dureza, tamanho, forma, cor e resili?ncia. O objetivo do presente estudo foi comparar pelo ensaio de microtra??o a resist?ncia ? ades?o de restaura??es biol?gicas ap?s cimenta??o no substrato dentin?rio em compara??o as convencionais restaura??es est?ticas cer?micas e analisar suas ?reas de fratura. Foram selecionados vinte e quatro terceiros molares humanos h?gidos, rec?m-extra?dos, que tiveram suas por??es coron?rias seccionadas em dentina e aleatoriamente divididos em dois grupos (n=12), grupo controle (Restaura??es Cer?micas IPS e.max ZirPress) e grupo experimental (Restaura??es Biol?gicas). Para confec??o das restaura??es biol?gicas, discos de dentina foram seccionados com espessura de 2,0 mm cada. Pastilhas de cer?mica foram confeccionadas com as mesmas dimens?es dos discos de dentina. As restaura??es foram cimentadas com cimento resinoso Rely X ARC e ap?s 24 horas submetidos a 10.000 ciclos de termociclagem (5-55?C). Os dentes foram seccionados perpendicularmente ? interface de uni?o, gerando palitos de 1 mm2 e submetidos a ensaio de microtra??o com velocidade de 0,5 mm/min, utilizando uma c?lula de carga de 5Kg. Foi realizada an?lise do padr?o de fratura em lupa estereosc?pica com o aumento de 40x. Esp?cimes representativos foram caracterizados por MEV/EDS para an?lise da morfologia geral e composi??o qu?mica elementar quantitativa dos materiais. Esp?cimes representativos de cada grupo foram submetidas ao protocolo de nanoinfiltra??o com AgNO3 e analisados em MEV. Os dados foram analisados pelo teste t de Student para esp?cimes independentes (p ? 0.05) e do qui-quadrado. N?o foi observada diferen?a estat?stica significativa em rela??o ? resist?ncia ? ades?o. Houve diferen?a significativa (p=0,015) quanto ao tipo de fratura, com 75% de fraturas adesivas para o grupo experimental. As restaura??es biol?gicas apresentaram comportamento semelhante em termos de resist?ncia ? ades?o, quando comparadas ?s restaura??es cer?micas, podendo vir a ser consideradas alternativas para o restabelecimento est?tico-funcional de dentes posteriores. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Odontologia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2014. / ABSTRACT ?Biological restoration? offers excellent biocompatibility and maintains the esthetic and functional characteristics of the tooth, such as physiological wear, surface shine, texture, hardness, size, shape, color and resilience. The aim of the present study was to evaluate the bond strength of biological restorations on dentin in comparison to conventional porcelain restorations through a microtraction test and characterize areas of fracture. The crowns of 24 recently extracted sound human third molars were planed to the dentin and randomly divided into a control group (n = 12; porcelain restorations ? IPS e.max ZirPress) and experimental group (n = 12, biological restorations). Biological restorations were made from fragments of the teeth cut to a thickness of 2.0 mm. Porcelain crowns were made with the same dimensions as the biological fragments. All restorations were cemented with Rely X ARC resin and, after 24 hours, submitted to 10,000 thermal cycles (5 to 55 ?C). The teeth were sectioned perpendicularly to the interface of the union for the obtainment of samples measuring 1 mm2, which were submitted to microtraction using the EZ Test - L universal testing machine operating at 0.5 mm/min with a 5 Kg cell load. Standard fracture analysis was performed with a stereomicroscopic magnifying glass (magnification: 40 x). Representative samples were characterized by scanning electron microscopy (SEM) for the analysis of general morphology and the quantitative element composition of the materials. Additional representative samples from each group were submitted to nano-injection with AgNO3 and analyzed using SEM. Data analysis involved the Student?s t-test for independent samples and the chi-squared test (p ? 0.05). No significant difference in bond strength was found, but a significant difference was found regarding the type of fracture (p = 0.015), with an adhesive fracture rate of 75% in the experimental group. Biological restorations demonstrate similar behavior to that found in porcelain restorations with regard to bond strength and constitute a viable option for the reestablishment of function and esthetics on posterior teeth.

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