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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.
361

Die staatswissenschaftlichen anschauungen Dirck Graswinckel's ...

Liesker, G. J. January 1901 (has links)
Inaug.-diss.--Freiburg (Schweiz).
362

The sacred in art : an interpretative study of Bernard Lonergan's theory of art /

O'Neill, Joanne Monica, January 2003 (has links)
Thesis (M.A.)--Memorial University of Newfoundland, 2003. / Bibliography: leaves 109-113.
363

Transformação genética de maracujazeiro azedo para resistência ao vírus do endurecimento dos frutos (Cowpea aphid-borne mosaic virus - CABMV) / Genetic transformation of yellow passionfruit for resistance to woodiness virus (Cowpea aphid-borne mosaic virus CABMV)

Alessandra Cristina Boffino de Almeida Monteiro Hara 26 March 2010 (has links)
A cultura do maracujazeiro é afetada pela virose causada pelo Cowpea aphid-borne mosaic virus (CABMV), provocando a redução da qualidade e produtividade dos frutos e, em alguns casos, pode inviabilizar o cultivo comercial desta espécie. Uma alternativa para o controle de doenças viróticas é o desenvolvimento de plantas resistentes pela transformação genética. O objetivo deste trabalho foi a obtenção de plantas transgênicas de maracujazeiro (Passiflora edulis f. flavicarpa), utilizando 2 construções gênicas contendo a região codificadora do gene da proteína capsidial do CABMV. A construção pCABMV-asCP, que contém um fragmento na orientação antisenso e a construção pCABMV-dsCP, que contém fragmentos senso e antisenso do gene da proteína capsidial, separados por um íntron, uma construção hairpin. Para os experimentos de transformação genética, via Agrobacterium tumefaciens, foram utilizados os explantes de segmentos de hipocótilo e discos de folhas jovens das variedades FB-100, IAC-275 e IAC-277. Após 2 - 3 dias de co-cultivo em meio de cultura MS (MURASHIGE; SKOOG, 1962) contendo acetosseringona (100 mM), os explantes foram transferidos para meio de cultura de seleção e regeneração constituído de sais minerais e vitaminas de MS, suplementado com canamicina (100 mg/L) + cefotaxima (500 mg/L) + nitrato de prata (4,0 mg/L), pH 5,8 e os reguladores BAP, TDZ e combinação de BAP e TDZ. Após 4 - 6 semanas, as gemas adventícias desenvolvidas foram transferidas para meio de cultura de alongamento MSM + GA3 (1,0 mg/L) + cefotaxima (500 mg/L) + nitrato de prata (4,0 mg/L). As plantas desenvolvidas foram aclimatizadas e analisadas por PCR, utilizando-se primers específicos para a detecção dos transgenes. Foram identificadas 30 plantas transgênicas PCR positivas para do gene nptII, sendo 11 positivas para o fragmento antisenso da proteína capsidial do CABMV e 2 positivas para o fragmento da construção gênica hairpin. Até o momento, a integração dos transgenes foi confirmada por Southern blot em 4 plantas. Paralelo aos experimentos de transformação genética, foram avaliadas plantas de maracujazeiro das variedades IAC-275 e IAC-277, obtidas em experimentos anteriores, com a construção gênica pCABMV-CP, que contém o gene da proteína capsidial do CABMV. A análise de Southern blot de 14 plantas destes experimentos, confirmou a integração do transgene em 13 plantas, as quais foram propagadas e inoculadas mecanicamente com 3 isolados do CABMV (SP, RJ, CE). A linhagem T16 foi resistente as 3 inoculações, com os 3 isolados testados. Clones desta linhagem foram analisados por RT-PCR, comprovando a transcrição do transgene / The yellow passionfruit is affected by Cowpea aphid-borne mosaic virus (CABMV), which causes a decrease in fruit quality and productivity and in some cases making it unpractical for commercial cultivation of this species. Ann alternative for the control of virus diseases is the development of resistant plants through genetic transformation techniques. The objective of this work was to obtain passion fruit (Passiflora edulis f. flavicarpa) transgenic plants with two different gene constructs derived from the CABMV coat protein coding region. pCABMV-asCP contains the gene fragment in an antisense direction and pCABMV-dsCP contains a sense and antisense coat protein gene fragments, separated by intron, a hairpin construct. The genetic transformation experiments with Agrobacterium tumefaciens, were done in hypocotyl segments and young leaf disks explants from varieties FB-100, IAC-275 and IAC-277. After two to three days in co-culture in MS culture medium (MURASHIGE; SKOOG, 1962) supplemented with acetoseringone (100 mM) the explants were subcultured to medium for selection and regeneration, composed of MS minerals and vitamins, supplemented with kanamycin (100 mg/L), cefotaxime (500 mg/L) and silver nitrate (4.0 mg/L), at pH 5.8, and the growth regulators BAP, TDZ and combination of BAP and TDZ. After four to six weeks, the adventitious buds developed were transferred to an elongating medium composed of MSM salts supplemented with GA3 (1.0 mg/L), cefotaxime (500 mg/L) and silver nitrate (4.0 mg/L). Plants were acclimatized and analyzed by PCR, with specific primers for the transgenes detection. Thirty transgenic plants were identified as PCR positive for the nptII gene, with 11 being positive for the antisense fragment of the CABMV coat protein gene and two positive for the hairpin gene construct fragment. Currently, the transgene integration was confirmed by Southern blot analysis in four plants. Simultaneously to the genetic transformation experiments, passionfruit plants, varieties IAC-275 e IAC-277, obtained from previous experiments with pCABMV-CP, which contains CABMV coat protein gene, were analized. The Southern blot analysis of 14 plants from these experiments confirmed the transgene integration in 13 plants, which were propagated and mecanically inoculated with three CABMV isolates (SP, RJ, CE). Line T16 was resistant to three inoculations with all three isolates tested. Clones from this line were analyzed by RT-PCR which confirmed the transgene transcription
364

Unidades f-unitárias em um anel de grupo intergral

Barbosa, Elen Deise Assis 16 April 2013 (has links)
Submitted by Marcio Filho (marcio.kleber@ufba.br) on 2016-06-07T13:38:55Z No. of bitstreams: 1 Elen_dissert_princ.pdf: 780037 bytes, checksum: 190cde1ac440feff303767a5c415a47b (MD5) / Approved for entry into archive by Uillis de Assis Santos (uillis.assis@ufba.br) on 2016-06-07T18:00:27Z (GMT) No. of bitstreams: 1 Elen_dissert_princ.pdf: 780037 bytes, checksum: 190cde1ac440feff303767a5c415a47b (MD5) / Made available in DSpace on 2016-06-07T18:00:27Z (GMT). No. of bitstreams: 1 Elen_dissert_princ.pdf: 780037 bytes, checksum: 190cde1ac440feff303767a5c415a47b (MD5) / O presente trabalho tem como objetivos estudar o subgrupo de todas as unidades de um anel de grupo integral bem como o subgrupo das unidades generalizadas; apresentar a relação entre estes subgrupos e o grupo das unidades. Verifica-se que o subgrupo das unidades generalizadas é exatamente o normalizador do subgrupo das unidades e que quando o grupo é periódico, o normalizador do subgrupo das unidades generalizadas é o próprio subgrupo. Além disso, serão caracterizados grupos para os quais se tenha o subgrupo das unidades bicíclicas sendo um subgrupo das unidades generalizadas. Finalmente, serão apresentados resultados que podem ser estendidos para a partir de e algumas relações entre as unidades hipercentrais de um anel de grupo integral e as unidades generalizadas.
365

Možnosti rozvoje úseku F&B WELLNESS HOTELU FRYMBURK / Opportunities of development F&B section of WELLNESS HOTEL FRYMBURK

PRŮŠOVÁ, Lucie January 2013 (has links)
The presented thesis deals with food and beverage section of Wellness Hotel Frymburk. The aim of the thesis is to analyze product of food and beverage section of Wellness Hotel Frymburk, comparasion with dining facilities in the selected area. An important goal is also a reccomendation for the further development of the product the studied hotel. Also will be inquired customer satisfaction with the current state of the service provided in this thesis. They will be also consulted on the opinions of management at current issues. In this thesis will be solved particulary the issue of regional gastronomy and employees in food service.
366

Caractérisation mécanique des matériaux constitutifs des tubes roulés-soudés pour leur mise en forme par hydroformage dans un contexte industriel. / Mechanical characterization of rolled-welded tubes materials for tube hydroforming in an industrial setting

Vitu, Ludovic 11 December 2017 (has links)
L’hydroformage de tube nécessite l’emploi d’outillage coûteux et la phase de mise au point utilise intensivement la simulation par éléments finis. Pour ces simulations, il est nécessaire de disposer de données matériaux adaptées dans le domaine plastique. Le comportement des matériaux utilisés en mise en forme dépend du mode de sollicitation. Ainsi, plusieurs essais de caractérisation tels que l’essai de traction et les essais de gonflement de flan et de tube sont traités dans ce travail.On s’intègre dans une démarche pragmatique afin d’offrir des méthodes simples pour une mise en œuvre dans un contexte industriel en limitant le nombre d’essai, une méthode expérimentale de caractérisation simple et une méthode d’analyse des résultats expérimentaux efficace. De plus, on se limite à des modèles matériaux disponibles dans tout type de code de calcul comme la loi d’écrouissage de Swift et le critère de plasticité de Hill 1948.Après une introduction des différents types d’hydroformage et des notions de bases du comportement plastique des matériaux, la mise en œuvre des essais est présentée. On retiendra qu’il existe plusieurs façons de post-traiter les résultats expérimentaux. La méthode classique a été choisie pour l’essai de traction, celle préconisée par Koç et al. est utilisée pour le gonflement de flan et enfin la méthode de Boudeau et Malécot a été adoptée pour le gonflement de tube.À partir des essais effectués sur un acier austénitique inoxydable de type AISI 304, plusieurs courbes d’écrouissages distinctes ont été obtenues. Des simulations numériques ont été menées afin de confronter ces lois de comportement sur la prédiction des profils des flans et des tubes déformés ainsi que sur les distributions d’épaisseur de ceux-ci. Enfin, le matériau ayant été considéré isotrope jusqu’à présent, on s’attache à l’influence de l’anisotropie du matériau dans le cadre de la mise en forme par hydroformage. Pour cela un plan complet est mené.Mots-clés : hydroformage, caractérisation de matériaux, tube, simulation E.F., expérimentation / Tube hydroforming requires the employment of expensive tooling and its industrial development makes an intensive use of finite element simulations. For these simulations, we need plastic material data. The material behavior, in forming, depends on the loading mode. Thus, several characterization tests such as uniaxial tensile test, the bulging test on sheet and tube, are investigated in this work.The works are conducted in the context of a pragmatic approach. The goal is to offer simple methods for implementation in an industrial setting based on a limited number of tests, a simple experimental method and an efficient method for post-processing experimental results. In addition, we limit ourselves to classical material models, available in any FE code, such as the Swift’s hardening law and the Hill 1948 plastic criterion.After the introduction of the different kind of hydroforming and the fundamentals on the plastic behavior of materials, the experimental tests are presented. There are many ways for post-processing the experimental results of these advanced testing methods. The conventional method is chosen for post-processing the experimental results obtained with the tensile test ; for the sheet bulging test, the method recommended by Koç et al. is used and the model proposed by Boudeau and Malécot’s is adopted for tube bulging test.The different tests are carried out on an austenitic stainless steel AISI 304 and, distinct hardening curves are obtained. Numerical simulations of the tests and a tube hydroforming operation are performed with the different hardening law. The FE results are compared; the comparisons are led on the resulting bulged sheet or tube and on the thickness distribution. Finally, the influence of the initial anisotropy in tube hydroforming is studied through a full Design Of Experiences.Keywords: hydroforming, material characterization, tube, F.E. simulation, experiment
367

Les O.N.G Humanitaires entre contraintes étatiques et transnationales : Les cas de Care International, C.R.S et M.S.F/F au Burundi / Humanitarian NGOs between governmental and transnational conditions : CARE International, CRS and MSF in Burundi

Niyonizigiye, Pascal 18 April 2012 (has links)
Les trois ONG humanitaires (CARE International, CRS et MSF/F) qui sont intervenues au Burundi de 1993 à 2005 ont réalisé des projets importants pour le pays. Ces acteurs transnationaux sont financés par des Etats, des Organisations internationales et des donateurs privés. C’est ainsi que l’on peut les qualifier d’acteurs intermédiaires parce qu’ils sont soumis aux contraintes étatiques et transnationales. Les financements étatiques sont motivés par la volonté de pousser les ONG humanitaires à servir des intérêts nationaux des Etats-bailleurs tandis que le financement privé légitime leur nature apolitique tout en les obligeant à se comporter comme des entreprises commerciales. Nonobstant cette nature hybride, dans chaque ONG existent des agents philanthropiques, qui travaillent juste pour l’Humanitaire. / The three humanitarian NGOs (CARE International, CRS and MSF/F) which have been operating in Burundi since 1993 to 2005 realized important projects for the country. These Transnational actors are funded by States, international organizations and private donators. That is why we can call them intermediate actors because they are submitted to governmental and transnational conditions. Static funding urges these NGOs to operate according to the national interests while private funding legitimates their transnational nature and justifies their “charity business”. Besides this hybrid nature, there are philanthropic agents in each of these three humanitarian NGOs.
368

O efeito do treinamento neuromuscular integrativo no desempenho motor de crian?as praticantes de futebol / The effect of integrative neuromuscular training in the motor performance of children soccer practitioners

Alexandre, Diego Rafael de Oliveira 28 July 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-02-15T12:44:59Z No. of bitstreams: 1 DiegoRafaelDeOliveiraAlexandre_DISSERT.pdf: 1747949 bytes, checksum: bba3f55136a533f5d8f403bd5439c70e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-02-19T21:45:41Z (GMT) No. of bitstreams: 1 DiegoRafaelDeOliveiraAlexandre_DISSERT.pdf: 1747949 bytes, checksum: bba3f55136a533f5d8f403bd5439c70e (MD5) / Made available in DSpace on 2018-02-19T21:45:41Z (GMT). No. of bitstreams: 1 DiegoRafaelDeOliveiraAlexandre_DISSERT.pdf: 1747949 bytes, checksum: bba3f55136a533f5d8f403bd5439c70e (MD5) Previous issue date: 2017-07-28 / O presente estudo tem como objetivo avaliar os efeitos do treinamento neuromuscular integrativo (INT) no desempenho motor (DM) em crian?as entre 06 a 10 anos. Foi analisada uma amostra de 38 crian?as do sexo masculino praticantes de futebol divididos em dois grupos: 20 no grupo do treinamento neuromuscular integrativo (GINT) e 18 no grupo controle (GC). Em seguida, foi aplicado o question?rio socioecon?mico para os pais, n?vel de atividade f?sica di?ria para os integrantes do estudo e a avalia??o da predi??o da idade ?ssea (CABRAL, 2013). Para determinar o efeito do INT no DM foi realizado uma bateria de testes f?sicos para a avalia??o do equil?brio, flexibilidade, agilidade, velocidade e pot?ncia anaer?bica de membros inferiores em tr?s momentos, antes (pr?) durante (6 semanas) e ap?s (12 semanas) de realiza??o do INT.. O INT foi realizado duas vezes por semana, 20 minutos iniciais de cada treino e constou de cinco exerc?cios voltados para aptid?o f?sica relacionada ? sa?de e ao desempenho. para verificar a homogeneidade das vari?veis do estudo entre os grupos, aplicou-se teste t de Student n?o pareado e o teste de Mann-Whitney. Para observar o efeito do tempo e a intera??o do treinamento no desempenho motor entre os dois grupos foram utilizadas a ANOVA mista de medidas repetidas, al?m do teste Post- Hoc com ajuste de Bonferroni, com intuito de identificar poss?veis diferen?as. Desta forma, para a vari?vel equil?brio ocorreu diferen?a significativa no efeito do tempo para o grupo INT, F(1,5;55,3) =5.865, p= 0.009, ??= 0.14, nos momentos pr? para 12 semanas do GINT (p < 0.001, d = 0,74) e do momento seis semanas para 12 semanas (p= 0.005, d = 0,35). Bem como, observou-se o efeito da intera??o, F(1,5;55,3) = 6.536, p=0.006, ??= 0.14, entre o GINT e GC no momento 12 semanas. Para a flexibilidade encontrou-se melhoria significativa no efeito do tempo, F(1,2;45,5) = 11.620, p= 0.001, ??= 0,24, no GINT entre os momentos pr? para seis semanas (p= 0.02; d= 0,48) pr? para 12 semanas (p < 0.001; d = 0,75) e entre os momentos seis para 12 semanas (p= 0.003; d= 0,25). Na agilidade verificou-se o efeito do tempo, F (2,72) = 7.332, p= 0.001, ??= 0,16, no grupo interven??o somente entre os momentos pr? para 12 semanas (p = 0.02). Em rela??o a vari?vel velocidade revelou-se n?o haver efeito do tempo nos grupos, (F (1,5;54,4)= 2.422, p= 0.112, ??= 0,06), como tamb?m n?o houve intera??o dos grupos nos tempos, (F (1,5;54,4)= 0.059, p= 0.898, ??= 0,002).Para a pot?ncia anaer?bica de membros inferiores houve intera??o entre os grupos, F(1,2;44,8)= 6.644, p= 0.009, ??= 0.15, por?m o teste post hoc com ajuste de Bonferroni n?o identificou em qual tempo havia intera??o. Quando analisado a m?dia ?% entre os grupos nas vari?veis motoras, algumas vari?veis tiveram melhorias significativas nos momentos pr? para 12 semanas, sendo apresentados os seguintes resultados: equil?brio (w=62,0; p=0,005), flexibilidade (w=97,0; p=0,015) e pot?ncia anaer?bica de membros inferiores (w=94,0; p=0,012). A adi??o do INT ao treinamento sistem?tico aplicado a crian?as teve influ?ncia direta no desempenho motor na maioria das capacidades f?sicas no per?odo de 12 semanas, a t?cnica dos exerc?cios integrais, o volume e intensidade adequados forneceram adapta??es de natureza neuromuscular na qual possibilitou uma melhora na mec?nica do movimento. / The present study aims to evaluate the effects of integrative neuromuscular training (INT) on motor performance in children between 06 and 10 years old. A sample of 38 male soccer players were divided into two groups: 20 in the integrative neuromuscular training group (GINT), age: 8.2 ? 1.2 years; body mass: 28.4 ? 6.4 kg; height: 1.3 ? 0.1 m. In addition to the 18 for the control group (GC), age: 8.5 ? 1.3 years; body mass: 32.8 ? 8.9 kg; height: 1.3 ? 0.1 m. The socioeconomic questionnaire was then applied to the parents, daily physical activity level for the study participants, as well as to evaluate the prediction of bone age (CABRAL, 2013) through anthropometric measurements. To determine the effect of INT on DM, a battery of physical tests was performed to evaluate the balance, flexibility, agility, speed and anaerobic power of the lower limbs at three moments, before (during) (6 weeks) and after (12 weeks ) of INT. The INT was performed twice a week, 20 minutes after each training, and consisted of five exercises aimed at physical fitness related to health and performance. To verify the homogeneity of the study variables between the groups, we applied unpaired Student's t test and the Mann-Whitney test. To observe the effect of time and interaction of training on motor performance between the two groups, the mixed ANOVA of repeated measures was used, in addition to the Post-Hoc test with Bonferroni adjustment, in order to identify possible differences. Thus, for the balance variable, there was a significant difference in the time effect for the INT group, F (1.5; 55.3) = 5.865, p = 0.009, ?? = 0.14, at the pre-12 weeks GINT <0.001, d = 0.74) and from the moment 6 weeks to 12 weeks (p = 0.005, d = 0.35). As well, the interaction effect, F (1,5; 55,3) = 6,536, p = 0.006, ?? = 0.14, was observed between the GINT and GC at the moment 12 weeks. For flexibility, significant improvement in the time effect was found, F (1.2; 45.5) = 11.620, p = 0.001, ?? = 0.24, in GINT between the pre-six and six-week periods (p = 0.02; d = 0.48) and pre-12 weeks (p <0.001; d = 0.75), and between times six and 12 weeks (p = 0.003; d = 0.25). In the agility, the effect of time was found, F (2.72) = 7.332, p = 0.001, ?? = 0.16, in the intervention group only between the pre-12 weeks (p = 0.02). In relation to the velocity variable, there was no effect of time in the groups, (F (1,5; 54,4) = 2,422, p = 0.112, ?? = 0,06), as well as there was no interaction of the groups in the times , (F (1.5; 54.4) = 0.059, p = 0.898, ?? = 0.002). For the anaerobic power of lower limbs, there was interaction between the groups, F (1,2; 44,8) = 6,644, p = 0.009, ?? = 0.15, but the post hoc test with Bonferroni adjustment did not identify at what time there was interaction. When the mean ?% between the groups in the motor variables was analyzed, some variables had significant improvements in the moments pre-12 weeks, and the following results were presented: balance (w = 62.0, p = 0.005), flexibility 0, p = 0.015) and anaerobic power of lower limbs (w = 94.0, p = 0.012). The addition of INT to the systematic training applied to children had a direct influence on motor performance in the majority of physical abilities over the 12 week period, the technique of the integral exercises, the adequate volume and intensity provided neuromuscular adaptations in which an improvement in mechanics of movement
369

Contribuições de Karl Marx ao problema da mimese artística / Karl Marxs Contributions to the Problem of Artistic Mimesis

Ana Aguiar Cotrim 07 May 2015 (has links)
Esta tese toma três momentos da obra de Karl Marx em que temas estéticos são aventados: a formação da sensibilidade nos Manuscritos econômico-filosóficos de 1844, a passagem sobre a épica na Contribuição à crítica da economia política Introdução, de 1857 e o debate epistolar entre Marx, Engels e Lassalle sobre a peça do último, Franz von Sickingen, de 1859. No contexto desses temas, buscamos descobrir as contribuições de Marx ao problema da mimese artística, da objetividade e especificidade da arte. São abordados a objetivação, mimese, historicidade dos gêneros, especificidade do reflexo artístico, o indivíduo e universalidade na obra artística, gênero artístico e revolução. Ao tratar desses temas, procura-se colocar Marx em diálogo com momentos da tradição estética, em particular pontos presentes em Aristóteles, Shakespeare e Schiller, Lessing, Hegel e Feuerbach. Lateralmente, algumas consequências para o marxismo contemporâneo são trazidas à tona, como a crítica de Marx à arte diretamente política. O trabalho conta com as contribuições de G. Lukács e M. Lifschitz, para quem a obra de Marx dispõe as linhas fundamentais de um pensamento estético coerente, a despeito da forma esparsa. / This thesis takes three passages of Karl Marxs work which bring out aesthetic subjects: the formation of senses in the Economic and Philosophical Manuscripts of 1844, the famous passage on the epic in the Contribution to the Critique of Political Economy - Introduction, 1857, and the epistolary debate between Marx, Engels and Lassalle on the tragedy written by the latter, Franz von Sickingen, held in 1859. In those contexts, we search for Marxs contributions to the problem of artistic mimesis, objectivity and specificity of art. Objectification, mimesis, historicity of genres, artistic reflection specificity, individual and universality in artistic work, artistic genre and revolution are points approached. In order to address these issues, we put Marx in dialogue with relevant moments in aesthetic tradition, particularly points present in Aristotle, Shakespeare and Schiller, Lessing, Hegel and Feuerbach. Laterally, some consequences for contemporary Marxism are brought to light, such as Marx\'s critique of political art. The work counts on the contributions of G. Lukács and M. Lifschitz, for whom Marx\'s work provides the main lines of a coherent aesthetic thought, despite its sparse form.
370

Estudo de dosimetria gel polimérica em radioterapia com feixes de elétrons utilizando ressonância magnética e simulação Monte Carlo / Study of polymer gel dosimetry in Radiotherapy with electron beams using magnetic resonance imaging and Monte Carlo simulation.

Thatiane Alves Pianoschi 03 February 2014 (has links)
Radioterapia com feixe de elétrons tem sido empregada, frequentemente, para tratamentos de neoplasias superficiais, devido às características de alcance bem definido e alto gradiente de dose em pouca profundidade. Para que as novas técnicas radioterápicas com esse tipo de feixe possam ser implementadas com segurança é necessária a realização de um controle da qualidade rigoroso. Protocolos recomendam que o controle da qualidade para esse tipo de feixe seja realizado com câmara de ionização, porém dosímetros termoluminescentes, diodos e filmes também são empregados com essa finalidade. Entretanto, esses dosímetros não possuem simultaneamente um conjunto de características essenciais para realização do controle da qualidade, como alta resolução espacial, baixa dependência energética, possibilidade de uso em altos gradientes de dose e distribuição tridimensional de dose. Nesse trabalho avaliou-se a utilização do dosímetro polimérico MAGIC-f gel em aplicações em controle da qualidade em Radioterapia com feixes de elétrons. As leituras das amostras de gel foram realizas por ressonância magnética e simulação Monte Carlo foi utilizada para comparação dos resultados. Como parte de um controle da qualidade para feixe de elétrons, foram determinados parâmetros dosimétricos, como perfil de dose e porcentagem de dose em profundidade, e fatores de qualidade do feixe, como R50, em condições de referência e para campos pequenos. Da comparação entre os dados clínicos e MAGIC-f as diferenças máximas encontradas foram de 4%. Além disso, distribuições de dose de aplicações clínicas com feixes de elétrons foram avaliadas pelo método de comparação do índice gama. Considerando os critérios de 3% e 3 mm, os resultados obtidos para o índice gama mostraram concordâncias acima de 94% para os métodos dosimétricos utilizados. Dessa forma, de acordo com as medidas dosimétricas realizadas com o dosímetro MAGIC-f gel conclui- se que a dosimetria polimérica gel pode ser empregada como uma ferramenta auxiliar em procedimentos de controle da qualidade em Radioterapia com feixes de elétrons, assim como uma ferramenta na determinação das distribuições tridimensionais de dose para feixe de elétrons. / Electron beam radiotherapy has been used frequently for treatments of superficial tumors, due its characteristics of well-defined range and high dose gradient at low depth. For new radiotherapy techniques with this type of beam, a strict quality control is necessary for a safe implementation. Protocols recommend that the quality control for electron beams must be performed with an ionization chamber. However, thermoluminescent dosimeters, films and diodes are also used for this purpose. Although, these dosimeters do not have a set of essential characteristics for performing quality control, like high spatial resolution, low energy dependence, possibility of use in high dose gradients and three dimensional dose distribution acquisition. The present work evaluated the use of MAGIC-f gel dosimeter for the quality control in radiotherapy with electron beams. The readings of the gel samples were made by magnetic resonance imaging and Monte Carlo simulation was used to compare the obtained results. As part of a quality control for the electron beam parameters as percentage depth dose and beam profile were determined. Also beam quality factors, such as R50, were calculated in reference conditions and for small fields. The obtained results were compared with clinical data and MAGIC-f the maximum obtained difference was 4%. In addition, dose distributions from clinical applications with electron beams were evaluated by the gamma index. Considering the criteria of 3% DD and 3 mm DTA, the results showed concordance greater than 94% for all dosimetric methods. Thus, according to the dosimetric measurements through MAGIC-f gel dosimeter it can be inferred that the gel dosimeter can be used as auxiliary tool in the quality control procedures in radiotherapy to electron beam. Also, MAGIC-f is a useful a tool to determine tridimensional dose distributions of electron beam.

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