Dissertations / Theses: 'PMNC'

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Carneiro, Glauco de Figueiredo. "SourceMiner: Um Ambiente Integrado para Visualização Multi-Perspectiva de Software." http://wiki.dcc.ufba.br/PMCC/GlaucoCarneiro, 2013. http://wiki.dcc.ufba.br/PMCC/GlaucoCarneiro.

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Atividades de compreensão têm papel importante em engenharia de software. A leitura e a busca de informações no código fonte não são atividades triviais e requerem esforço significativo em sistemas de médio e grande porte. Atualmente, apesar da maioria dos ambientes de desenvolvimento de software (ADS) oferecer apoio às atividades de compreensão, eles ainda não adotaram plenamente técnicas e recursos de visualização para tal finalidade. Esta é uma limitação significativa dado que o ser humano tem maior capacidade para obter informação através da visão do que todos os outros sentidos combinados. Além disso, as próprias técnicas de visualização de software ainda não adotaram recursos de interação e coordenação já consolidados na área de visualização de informação. Esta tese propõe um ambiente interativo baseado em múltiplas visões chamado SourceMiner, desenvolvido como um plug-in da ADS Eclipse, para apoiar as atividades de compreensão de software. O SourceMiner traz novos recursos e técnicas para a área de visualização de software. O principal destes é o uso de múltiplas visões, já adotadas em visualização de informação e compatibilizadas para visualização de software através do conceito de perspectivas. O ambiente também utiliza mecanismos de coordenação entre as visões, zoom semântico e filtros interativos. O SourceMiner é um ambiente expansível no qual é possível incluir novas visões. Além disso, ele possui recursos de monitoramento de atividades a partir dos quais podem ser realizados estudos para a análise do perfil de uso do ADS e das funcionalidades oferecidas pelo próprio plug-in. A utilização integrada destes recursos é uma contribuição nova para a área de visualização de software. Foram realizados seis estudos experimentais para avaliar o uso do SourceMiner em atividades de compreensão de software. Os resultados indicam que o SourceMiner pode ser utilizado para apoiar a construção de modelos mentais que se adéquam às necessidades de compreensão daqueles que lidam tanto com atividades de desenvolvimento como de manutenção de software.
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Rodrigues, Júnior Methanias Colaço. "Identificação e validação do perfil neurolinguístico de programadores através da mineração de repositórios de software." http://wiki.dcc.ufba.br/PMCC/MethaniasColaco, 2013. http://wiki.dcc.ufba.br/PMCC/MethaniasColaco.

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Hodiernamente, o processo de desenvolvimento de software pode contar com a utilização de diversas ferramentas de apoio. Os sistemas de controle de versão, as listas de discussão entre as pessoas envolvidas no projeto e os sistemas de rastreamento de erros são usados freqüentemente para ajudar a controlar o andamento de projetos de software, produzindo repositórios de dados históricos. Nos últimos anos, pesquisadores vêm realizando análises lingüísticas nas listas de discussão de projetos de software para compreender as complexidades e especificidades do seu desenvolvimento. Uma abordagem inovadora para isso é usar a Teoria da Neuro-Lingüística. A Neuro-Lingüística postula que indivíduos, em contextos específicos, utilizam um sistema representacional preferencial (SRP) para cognição. Isto significa que apesar de diferentes recursos e canais cognitivos serem usados pelos desenvolvedores para entender o software, existem sistemas representacionais preferidos pelos mesmos. Nesta tese, apresentamos uma ferramenta de análise psicométrica baseada na Neuro-Lingüística (NEUROMINER) para classificar os Sistemas Representacionais Preferidos (SRP) de desenvolvedores de software. A avaliação experimental da abordagem foi realizada em três experimentos que visaram testar a classificação do SRP: (1) Um estudo realizado nas listas de discussão dos projetos do servidor Apache e do PostgreSQL; (2) Uma pesquisa de campo com engenheiros de software para estabelecer quais os tipos de sistemas representacionais são os preferidos pelos mesmos; e (3) Um experimento controlado feito na indústria para avaliação da efetividade da ferramenta neste tipo de ambiente. Os resultados indicaram que a nossa abordagem pode ser usada para classificar engenheiros de software com relação às suas preferências de representação para cognição. Esta classificação pode nortear a alocação de desenvolvedores em tarefas específicas e, possivelmente, melhorar a comunicação em organizações de desenvolvimento de software.
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Sá, Alirio Santos de. "Mecanismos Autonômicos de Tolerância a Falhas para Sistemas Distribuídos." http://wiki.dcc.ufba.br/PMCC/AlirioSa, 2013. http://wiki.dcc.ufba.br/PMCC/AlirioSa.

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As facilidades de processamento e comunicação oriundas das novas tecnologias têm promovido o surgimento de uma nova classe de ambientes distribuídos. Estes ambientes são caracterizados pela dinamicidade em suas composições, no provisionamento de seus recursos e nas características e requisitos de suas aplicações. Isto traz novos desafios à confiabilidade, a qual é um atributo essencial à grande maioria dos sistemas distribuídos modernos. Um destes desafios está na incapacidade, dos mecanismos tradicionais de tolerância a falhas, de atender aos requisitos de desempenho, ao mesmo tempo em que suportam a confiabilidade. Isto porque o projeto destes mecanismos requer um conhecimento prévio das características dos ambientes e de suas aplicações, para que possam oferecer configurações adequadas ao atendimento dos requisitos especificados -- isto representa um problema, uma vez que, nos ambientes distribuídos modernos, estas informações mudam dinamicamente. Neste contexto, nem mesmo os mecanismos adaptativos de tolerância falhas obtêm sucesso, pois realizam a sua configuração dinamicamente, mas confiam em comportamentos e requisitos definidos em tempo de projeto. Para enfrentar este desafio, esta Tese introduz os mecanismos autonômicos de tolerância a falhas, baseados em teoria de controle e capazes de se auto-configurar face às mudanças dinâmicas nas características do ambiente ou nos requisitos de suas aplicações. Com o intuito de demonstrar a viabilidade destes mecanismos, foram implementados e avaliados, como estudo de caso, detectores autonômicos de defeitos e protocolos autonômicos de comunicação em grupo, dois mecanismos básicos à construção de muitos sistemas distribuídos confiáveis. Estes mecanismos autonômicos de detecção e de comunicação em grupo são os primeiros da literatura a suportar a auto-configuração em tempo de execução, baseada em requisitos de qualidade de serviço definidos pelos usuários. Tais mecanismos foram avaliados, usando simulações, em condições de carga variadas e falhas. Mesmo sem trabalhos relacionados, para uma comparação direta de desempenho, os mecanismos autonômicos propostos foram comparados com mecanismos tradicionais de tolerância a falhas existentes na literatura. Estes mecanismos tradicionais usaram diferentes configurações definidas por parâmetros manualmente fixados. Os experimentos realizados demonstram que os mecanismos autonômicos propostos possuem, na maioria dos casos, desempenho superior que as diferentes configurações dos mecanismos tradicionais considerados, principalmente quando variações nas características da carga, mudanças nos requisitos ou reconfigurações dinâmicas no ambiente são considerados.
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Regnier, Paul Denis Etenne. "Optimal Multiprocessor Real-Time Scheduling via Reduction to Uniprocessor." http://wiki.dcc.ufba.br/PMCC/PaulRegnier, 2013. http://wiki.dcc.ufba.br/PMCC/PaulRegnier.

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Neste trabalho de doutorado, propõe-se RUN (Redução para Uniprocessor), um novo algoritmo de escalonamento para conjunto de tarefas periódicas com deadlines implícitas em sistemas multiprocessador de tempo real, nos quais as tarefas possuem restrições tanto no domínio do tempo quanto no domínio de valores. RUN apresenta as seguintes propriedades relevantes: - RUN é ótimo no sentido que ele produz um escalonamento correto, no qual todas as restrições temporais são atendidas, de qualquer sistemas de tarefas utilizando até 100% dos processadores da plataforma de tempo real; - RUN usa o conceito-chave do escalonamento do tempo ócio, chamado de escalonamento por dualidade, segundo o qual, em algum instante t, o escalonamento de uma tarefa utiliza tanto o conhecimento de seu tempo de execução restante, bem como o seu tempo ócio restante; - RUN baseia-se na diminuição do número de tarefas a ser escalonadas pela suas agregações em supertasks, os quais chamamos de servidores, com taxa acumulada não superior a 1. Cada servidor é responsável por escalonar o seu conjunto de tarefas clientes, de acordo com alguma política de escalonamento; - RUN utiliza o princípio original de justiça global (Gfair), de acordo com o qual cada servidor de um conjunto de tarefas T é garantido de executar por um tempo proporcional à taxa acumulada das tarefas de T entre cada duas deadlines das tarefas de T; - RUN reduz o problema do escalonamento de um conjunto de tarefas em/m/ processadores no problema equivalente do escalonamento de um ou mais conjuntos de tarefas diferentes em sistemas monoprocessador; - RUN supera significativamente os algoritmos ótimos existentes em termos de preempções com um limite superior de O(log m) preempções média por jobs em/m/ processadores.
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Schauenburg, Andrea J. A. "Molecular mechanisms underlying pMHC-II recognition." Thesis, Cardiff University, 2016. http://orca.cf.ac.uk/96291/.

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The immune system is a complex network of cells and molecules working together with the purpose of fending off potentially harmful pathogens. CD4+ T cells take key roles within this network by orchestrating a multitude of its players. They recognise pathogen or self-derived peptides (p) bound to molecules of the major histocompatibility class II (MHC-II) through their T cell receptor (TCR). Cytokines secreted in response to recognition aid antibody production and cytotoxic T cell activity, both critical for anti-viral immunity. In this thesis, TCR/pMHC-II interactions were investigated using a range of functional and molecular approaches in order to gain valuable insight into the mechanisms underlying successful antigen recognition. To aid these investigations, a versatile, insect cell based expression system for HLA-DR1 was successfully implemented to generate soluble protein for use in multimer stainings and biophysical assays. Two HLA-DR1 restricted peptides encoded within influenza heamagglutinin (HA) were confirmed as being highly conserved making them ideal targets for vaccine development and allowing identification of influenza specific CD4+ T cells. Furthermore, the various roles of peptide flanking residues (PFR) were investigated using two experimental models. In a HA derived peptide, C-terminal PFR proved essential for peptide binding stability to HLA-DR1 and in consequence, CD4+ T cell activation. Clonotyping of CD4+ T cells grown against peptides of varying PFR lengths showed that TCR gene selection was heavily influenced by PFR. A HIV gag24 derived peptide displaying an unusual secondary structure within its N-terminal PFR gave further insight into how seemingly small modifications to PFR can have wide reaching impact on CD4+ T cell activation. Both studies highlighted the need for more in depths investigations into this emerging field and the wide reaching impacts of this inherent feature of MHC-II restricted peptides. Overall, the results in this thesis added novel insight into the mechanisms underlying TCR/pMHC-II interactions.

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Patikarnmonthon, Nisa. "PMPC-PDPA polymersomes-mediated siRNA delivery." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/5476/.

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Polymersomes made from the amphiphilic diblock copolymers, PMPC-PDPA, are proposed to serve as a siRNA carrier with pH-responsive property that provides endosomal escape. The main purpose of this work is to investigate the ability of polymersomes to provide effective intracellular delivery of siRNA into HeLa cells. Encapsulation of siRNA into polymersomes was performed by pH-switch and electroporation method, both techniques enable siRNA encapsulation. No alteration of polymersomes size and morphology was observed in DLS and TEM. Purification of polymersome was conducted to ensure that no free siRNA or polymer remained. Intracellular delivery was examined by using fluorescence-labelled siRNA to track the internalisation. Flow cytometry and fluorescence microscope were used to study the cellular uptake of polymersomes and siRNA. siRNA is successfully delivered with the distribution of siRNA signal throughout the cell, with stronger signal compared with Lipofectamine. Kinetic uptake of siRNA suggests that siRNA can be effectively delivered to most cells within 20 hours. In addition, evidence of endosomal escape of siRNA delivered by polymersomes was observed. Silencing activity of siRNA was determined by qPCR and Western blot, mRNA and protein expression of Lamin A/C as a target gene were not significantly decreased. Cytotoxicity and other cellular response, including pro-inflammatory response and interferon response, were investigated. Polymersomes provide very low cytotoxicity and no pro-inflammatory response, unlike Lipofectamine. Moreover, the gene expression profile of interferon response indicates the possible apoptosis occurrence in Lipofectamine treated cells, but not in polymersomes treated cells. The information suggests two possible factors that influence the silencing activity of siRNA delivered by polymersomes; the incomplete characterisation of siRNA process and the cellular response from carriers.

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Bonijoly, Bastien. "Effets d'annonces de tapering par la Fed sur les pays d'Afrique du Nord et MENA et leur intégration au sein du système financier international." Electronic Thesis or Diss., Toulon, 2019. http://www.theses.fr/2019TOUL2005.

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Cette thèse se consacre dans un premier temps à la compréhension des effets d’annonces de tapering réalisées par la Fed durant la période 2013-2015 et l’impact que ces annonces ont eu sur les pays d’Afrique du Nord et plus généralement des pays de la zone MENA et Afrique possédant des marchés financiers. Cela permet d’ainsi d’évaluer la sensibilité de ces pays aux chocs de politiques monétaires internationales, et permet ainsi de voir l’impact que cela a même sur des pays ayant de petits marchés financiers.Dans un second temps, cette thèse s’attache à estimer la place des pays de cette zone et de leur intégration au sein du système financier international à l’aide d’une topologie de réseau. Cela permet ainsi de voir les interactions, ou plutôt les connexions qui lient les pays de cette zone à l’intérieur même de celle-ci entre eux, et aussi avec le reste du réseau. Cette thèse permet d’étudier une thématique oubliée de la littérature au niveau des pays sélectionnés et dans un second temps, apporte un éclairage intéressant sur la question de l’intégration financière à l’aide d’une méthodologie atypique
The first purpose of this thesis is to assess the impact of tapering’s announcement by the Fed during the period 2013 / 2015, and the impact these announcements had on assets prices in North Africa and more generally in MENA and African countries with the most developped financial sectors. We will assess, by studying the relevant events, the vulnerability of those countries to the shock in the international monetary policy sequence; consequently enabling a characterization of its impact, even on countries with relatively lowly developped financial markets. The second purpose of this thesis is to investigate the position of these countries within a large sample of MENA economies, and the remainder of the international financial system using a topological network. This enables to outline the interactions that bind those countries with each other, and also with the rest of the network —financial markets of advanced economies and other emerging economies. This thesis tackles a scarcely covered theme within the existing literature for the selected countries and also sheds new light on the question of financial integration using an atypical methodology

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Stewart-Jones, Guillaume B. E. "Structural and functional analyses of human pMHC/TCR complexes." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.413213.

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Avila, Olias Maria Milagros. "Cellular uptake of PMPC-PDPA polymersomes in mammalian cells." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/6870/.

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Polymersomes (synthetic polymeric vesicles), formed by the self-assembly of amphiphilic block copolymers in water attract great attention as drug delivery systems and as diagnostic/imaging tools. Our group has shown that 2-(methacryloyloxy)ethyl phosphorylcholine-block-2-(diisopropylamino)ethyl methacrylate (PMPC-PDPA) polymersomes are of special interest due to their ability to encapsulate a wide range of therapeutic molecules including anticancer compounds, antibiotics, antibodies, and nucleic acids, and their capacity to deliver their cargo intracellularly, both in vitro and in vivo, without promoting cellular toxicity or stress. The favourable uptake kinetics and toxicological profile of PMPC-PDPA polymersomes justify a thorough study on the cellular interactions and mechanisms underlying their uptake, which was the aim of this thesis. Exploring different polymersome production methods we studied the impact that the physical properties of PMPC-PDPA polymersomes (nanoparticle size and shape) have on their cellular uptake. Using flow cytometry and fluorescence microscopy we demonstrated that both spherical and tubular polymersomes could be used as intracellular delivery vectors. In addition, spherical and tubular polymersomes presented different uptake kinetic profiles, opening new avenues to modulate the temporal delivery of a cargo. In a parallel line of work we identified receptor-mediated endocytosis as a common pathway for the internalisation of PMPC-PDPA polymersome in mammalian cells. Studying polymersome uptake in the presence of antagonists and neutralising antibodies, we identified two families of transmembrane proteins mediating PMPCPDPA polymersome endocytosis and the specific receptors facilitating polymersome uptake. In addition, different endocytic pathways and molecules (i.e. dynamin, BAR domain proteins) were investigated in relation with polymersome internalisation by means of chemical inhibitors, dominant negative proteins and siRNA knockdown. Polymersome endocytosis seems to be dominated by a high level of promiscuity and the ability of PMPC-PDPA polymersome to induce their uptake, which could be translated in new therapeutic applications with a great clinical impact.

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Lima, Elton Carvalho de [UNESP]. "Propriedades dielétricas de cerâmicas relaxoras PMN." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/92008.

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O presente estudo destina-se à investigação sistemática das propriedades dielétricas de cerâmicas ferroelétricas relaxoras de Pb(Mg1/3Nb2/3)O3 (PMN). A resposta dielétrica em ferroelétricos relaxores, sob diferentes condições de excitações elétricas externas, deve ser considerada com especial atenção, posto que a fenomenologia para os estudos reportados na literatura não está completamente fundamentada. Sob tais considerações, a finalidade do presente trabalho é investigar o comportamento da permissividade dielétrica (e = e´ + i e´´) de cerâmicas PMN em função de campos elétricos AC e DC, em uma ampla faixa de freqüências (20 Hz a 1 MHz) e temperatura (20 K a 800 K). O estudo da dispersão dielétrica com a freqüência foi realizado em termos da relação de Vogel-Fulcher, permitindo a determinação da energia de ativação (Ea) e da temperatura de congelamento (Tf) dos dipolos para a amostra investigada. O comportamento do efeito relaxor em função de campos elétricos externos AC e DC foi avaliado e comparado com os resultados recentes reportados na literatura.
The present study is destined to the systematic investigation of dielectric properties on relaxor ferroelectric lead magnesium niobate Pb(Mg1/3Nb2/3)O3 (PMN). The answer dielectric in ferroelectrics relaxors, under different conditions of external electric excitements, should be considered with special attention, position that the phenomenology for the studies moderated in the literature is not completely based. Under such considerations, the purpose of the present work is to investigate the behavior of the dielectric permittivity ( = ’+ i ”) of ceramic PMN in function of fields electric AC and DC, in a wide interval of frequencies (20 Hz to 1 MHz) and temperature (20 K to 800 K). The study of the dielectric dispersion with the frequency was accomplished in terms of the relationship of Vogel-Fulcher, allowing the determination of the activation energy (Ea) and of the freezing temperature (Tf) of the dipoles for the investigated sample. The behavior of the effect relaxor in function of fields external electric AC and DC was evaluated and compared with the recent results moderated in the literature.

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Lima, Elton Carvalho de. "Propriedades dielétricas de cerâmicas relaxoras PMN /." Ilha Solteira : [s.n.], 2008. http://hdl.handle.net/11449/92008.

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Orientador: Eudes Borges de Araújo
Banca: José de Los Santos Guerra
Banca: Jean-Claude M'Peko
Resumo: O presente estudo destina-se à investigação sistemática das propriedades dielétricas de cerâmicas ferroelétricas relaxoras de Pb(Mg1/3Nb2/3)O3 (PMN). A resposta dielétrica em ferroelétricos relaxores, sob diferentes condições de excitações elétricas externas, deve ser considerada com especial atenção, posto que a fenomenologia para os estudos reportados na literatura não está completamente fundamentada. Sob tais considerações, a finalidade do presente trabalho é investigar o comportamento da permissividade dielétrica (e = e' + i e') de cerâmicas PMN em função de campos elétricos AC e DC, em uma ampla faixa de freqüências (20 Hz a 1 MHz) e temperatura (20 K a 800 K). O estudo da dispersão dielétrica com a freqüência foi realizado em termos da relação de Vogel-Fulcher, permitindo a determinação da energia de ativação (Ea) e da temperatura de congelamento (Tf) dos dipolos para a amostra investigada. O comportamento do efeito relaxor em função de campos elétricos externos AC e DC foi avaliado e comparado com os resultados recentes reportados na literatura.
Abstract: The present study is destined to the systematic investigation of dielectric properties on relaxor ferroelectric lead magnesium niobate Pb(Mg1/3Nb2/3)O3 (PMN). The answer dielectric in ferroelectrics relaxors, under different conditions of external electric excitements, should be considered with special attention, position that the phenomenology for the studies moderated in the literature is not completely based. Under such considerations, the purpose of the present work is to investigate the behavior of the dielectric permittivity ( = '+ i ") of ceramic PMN in function of fields electric AC and DC, in a wide interval of frequencies (20 Hz to 1 MHz) and temperature (20 K to 800 K). The study of the dielectric dispersion with the frequency was accomplished in terms of the relationship of Vogel-Fulcher, allowing the determination of the activation energy (Ea) and of the freezing temperature (Tf) of the dipoles for the investigated sample. The behavior of the effect relaxor in function of fields external electric AC and DC was evaluated and compared with the recent results moderated in the literature.
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Madalli, Shimona. "An investigation into sex-differences in leukocyte mobilisation and recruitment in response to acute inflammation." Thesis, Queen Mary, University of London, 2012. http://qmro.qmul.ac.uk/xmlui/handle/123456789/8641.

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Females are relatively protected from inflammatory diseases, particularly conditions that are characterised by excessive tissue infiltration of neutrophils (PMNs), such as ischaemia/reperfusion (I/R) injury. Therefore, understanding sex-differences is very important particularly for appropriate treatment of inflammatory disorders in men and women. Unfortunately, efforts to exploit sex-differences therapeutically have been unsuccessful since the precise mechanisms that confer the protective advantage in females over males are unclear. Many fundamental aspects of the nature of sex-differences have not been investigated, particularly in the regulation of PMN mobilisation from the bone marrow during acute inflammation. The aim of this thesis is to determine the nature and mechanism of leukocyte activation and recruitment in males and females, particularly in I/R. This thesis demonstrates for the first time that regulation of PMN mobilisation during acute inflammation is distinct in females. In comparison to males, females demonstrate reduced expression of mediators that cause the release of PMNs, including GCSF, CXCR2 and CXCL5, and increased expression of CXCR4 and CXCL12, which mediate PMN retention in the bone marrow. Reduced granulopoiesis, PMN mobilisation and recruitment into tissues in response to inflammogens protect females from collateral damage incurred by PMN-derived mediators that contribute to tissue injury and loss of function. This thesis has also revealed a novel, and possibly predominant, role for the ELR+ CXC chemokine CXCL5 in mobilisation of tissue-damaging PMNs from the bone marrow, whereby CXCL5 production, PMN mobilisation and tissue infiltration was profoundly greater in males during acute inflammation. CXCL5 appears to stimulate PMN mobilisation by 1) upregulating CXCR2 v expression on bone marrow cells and simultaneously downregulating CXCR4 expression; 2) inducing its own expression; 3) stimulating GCSF expression; and 4) increasing PMN expression of β2 integrin. Thus, the thesis proposes that reduced CXCL5 expression, and increased CXCR4/CXCL12 expression, in females during acute inflammation may be a novel mechanism underlying the protection against tissue injury. The fact that these sex-differences were apparent in different species (rat, mouse), tissues (mesenteric, lung, kidney, heart), in response to different stimuli (mesenteric, renal, myocardial I/R and carrageenan-induced pleurisy) and shown both in vivo and in vitro, suggests that this is a fundamental, and more generalised, phenomenon in males and females following acute inflammation. The inherent differences between the sexes have important clinical implications in that they demonstrate the need of considering sex-differences in research. This thesis demonstrates that sex-differences must be taken into account when developing such therapies for specific inflammatory diseases such as I/R injury as there are major differences in the temporal profile of chemokines and the extent of PMN infiltration.

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Miranda, Edileuza Donizete Rocha. "Professor mediador escolar e comunitário – (PMEC): problematizando as consideradas boas práticas." Universidade do Oeste Paulista, 2016. http://bdtd.unoeste.br:8080/jspui/handle/jspui/1003.

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Due to the increase of violence in the school environment related to several situations that involve verbal, physical and symbolic aggressions carried out by basic education students, the Secretariat of Public Education of the State of Sao Paulo (SEESP), in partnership with the Secretariat of Public Security (SSP), has instituted the System of Public Protection in the State Educational System and the role of School and Community Mediator Teacher (PMEC), which aims to coordinate planning of actions destined to prevention, mediation and resolution of conflicts in the school environment. This investigative proposal has the goal of questioning the effectiveness of school mediation through analyses of the PMEC’s considered good practice in a public school that is connected to a Board of Education (DE) in the inner state of Sao Paulo. A case study was methodologically carried out and oriented by a qualitative research approach, in which techniques for data generation consist in analyses of normative resolutions, reports and evidences from the performed work, book of occurrences and semi-structured interviews. This thesis has shown many fragilities regarding the School Protection System, as these public policies interfere direct and indirectly in the effectiveness of the PMEC’s work in the Sao Paulo State schools. Through the obtained data, it was noticed that school mediation goes through a strong transition period, going from the Retributive Law, which has a more punitive nature, to the Restorative Law, based in restorative practices in conflict resolution. It was possible to perceive the effectiveness in the PMEC’s work through what is considered good practice; however, many things need to be reviewed so that a more pacific school environment can be implemented. This will only be possible with a collaborative work between the school agents, investments in formation, monitoring and assessment of projects. Finally, this research’s results aim to assist in subsidizing other PMECs’ work, broadening the debate on public policies and contributing with proposals that can come to improve the work performed by these professionals on behalf of constructing a peace culture inside and outside schools.
Devido ao aumento das violências, no ambiente escolar, em relação às diversas situações que envolvem agressões verbais, físicas e simbólicas protagonizadas por estudantes da educação básica, a Secretaria de Educação do Estado de São Paulo (SEESP), em parceria com a Secretaria de Segurança Pública (SSP), instituiu o Sistema de Proteção Escolar na Rede Estadual de Ensino e a função de Professor Mediador Escolar e Comunitário (PMEC), que visa a coordenar o planejamento de ações destinadas à prevenção, mediação e resolução de conflitos, no ambiente escolar. A presente proposta investigativa tem como objetivo problematizar a efetividade da mediação escolar a partir das análises das consideradas boas práticas do PMEC, em uma escola pública pertencente a uma Diretoria de Ensino (DE) do interior do Estado de São Paulo. Metodologicamente, efetuamos um estudo de caso orientado pela abordagem qualitativa de pesquisa, cujas técnicas para a geração de dados consistiram em análises das resoluções normativas, relatórios/evidências dos trabalhos realizados, livros de ocorrências, entrevistas semiestruturadas. Essa dissertação demonstrou muitas fragilidades, no que se refere ao Sistema de Proteção Escolar, pois essas políticas públicas interferem direta e indiretamente na efetivação do trabalho do PMEC, nas escolas paulistas. Pelos dados obtidos, percebemos que a mediação escolar passa por um forte momento de transição, da Justiça Retributiva de cunho mais punitivo para a Justiça Restaurativa, que tem suas bases nas práticas restaurativas de resolução de conflitos. Pôde-se observar a efetividade do trabalho do PMEC, através das consideradas boas práticas, no entanto, muitas coisas necessitam ser revistas, para a implantação de um ambiente escolar mais pacífico, o que só será possível por meio de um trabalho coletivo entre os agentes escolares, investimentos em formação, acompanhamento e avaliação do projeto. Enfim, espera-se que os resultados desta pesquisa sirvam para subsidiar o trabalho de outros PMECs, ampliando o debate sobre políticas públicas, contribuindo com propostas que venham a aprimorar o trabalho realizado por esses profissionais, em prol da construção de uma cultura de paz, dentro e fora das escolas.

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14

Miller, Peter Jason Collins Edward J. "The mechanisms of pMHC recognition by the AHIII T cell receptor." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2008. http://dc.lib.unc.edu/u?/etd,1924.

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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2008.
Title from electronic title page (viewed Dec. 11, 2008). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Biochemistry and Biophysics." Discipline: Biochemistry and Biophysics; Department/School: Medicine.

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15

Prouton, Oliver Rupert. "The PMN selected survey for southern gravitational lenses." Thesis, Imperial College London, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271157.

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16

Schneider, Neide Beschtold. "Parque Municipal do Maciço da Costeira (PMMC) :: caracterização da área e a conservação dos recursos hídricos. Estudo de caso das comunidades do entorno ao PMMC em Florianópolis SC /." Florianópolis, SC, 1999. http://repositorio.ufsc.br/xmlui/handle/123456789/81168.

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Dissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico.
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A pesquisa tem como objetivo constatar o abastecimento de água da comunidade e o conhecimento do Parque Municipal do Maciço da Costeira (PMMC), junto aos moradores do entorno, nos bairros; Pantanal, Costeira do Pirajubaé, Córrego Grande Canto da Lagoa, Porto da Lagoa e Rio Tavares em Florianópolis. Realizaram-se entrevistas junto aos moradores as lideranças dos centros comunitários dos respectivos bairros do entorno, através da aplicação de 102 questionários que permitiram averiguar a expressividade do uso dos mananciais do PMMC, e os níveis de participação nas questões relacionadas ao meio ambiente. A elaboração de mapas permitiu relacionar a ocupação do solo com o abastecimento de água das comunidade do entorno, no sentido de contribuir com informações para conservação do ecossistema do PMMC. Para concluir, apresenta-se a síntese da realidade encontrada. Parque Municipal do Maciço da Costeira e seu entorno têm-se modificado sistematicamente pela pressão do crescimento urbano. Os principais fatores que levaram a estas alterações foram projetos de parcelamento do solo, pela valorização das áreas litorâneas e conseqüentes loteamentos irregulares, principalmente, em áreas de morros. Outro fato é pela prática cultural, das queimadas para renovação da pastagem, que deverão alterar a sustentabilidade da água pela população do entorno.. Neste sentido os impactos da continuidade da ocupação irregular e intensa nas áreas dos morros, deverá alterar este espaço com as seguintes conseqüências: prejuízos para o uso sustentável da água pelas populações do entorno. Uma constatação importante da pesquisa foi a falta de conhecimento por parte da população da existência de um parque municipal naquela área. A evidência de tal fato foi observada através das entrevistas realizadas, que mostraram ser de apenas cerca de 20% o montante dos moradores que têm conhecimento do PMMC, mesmo já se passando quatro anos da promulgação da Lei que o cria. Tendo em vista que esta população necessita dos poços e dos pequenos cursos d'água que nascem dentro dos limites do PMMC, o desconhecimento da existência dessa unidade de conservação é preocupante pela falta de perspectiva de conservação destes mananciais. Constata-se que entre os meios em que a educação ambiental poderia ser divulgada no PMMC, a população escolheu com maior porcentagem a divulgação através dos lideres comunitários e em segundo lugar pelos professores das escolas dos respectivos bairros.

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Ye, Zhan. "Yersinia pestis VIRULENCE FACTOR YopM UNDERMINES THE FUNCTION OF DISTINCT CCR2⁺Gr1⁺ CELLS IN SPLEEN AND LIVER DURING SYSTEMIC PLAGUE." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_diss/63.

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Yersinia pestis, the infective agent of bubonic and pneumonic plague, is classified as a category A agent of bioterrorism. YopM, a protein toxin of Y. pestis, is necessary for full virulence in a systemic plague mouse model with ambient-temperature grown bacteria. We used this model to identify the cells undermined by YopM. Natural killer (NK) cells were previously reported to be lost in spleen and blood in a YopM-associated way; however, NK cell depletion was found not to occur in liver, and ablation of NK cells had no effect on bacterial growth, indicating that NK cells are redundant for the YopM-mediated virulence mechanism. In mice either ablated for Gr1+ cells or lacking the chemokine receptor CCR2, wildtype growth was at least partially restored to the ΔyopM Y. pestis in both spleen and liver. In a mouse model of bubonic plague, CCR2 also was shown to be required for the ΔyopM Y. pestis to show wildtype growth in skin. These data pointed towards Gr1+CCR2+ cells, which include polymorphonuclear leukocytes (PMNs), inflammatory monocytes and inflammatory dendritic cells (iDCs), as key cellular components in controlling the in vivo growth of the ΔyopM Y. pestis. Recruitment of Gr1+CCR2+ cells into both organs was not YopM-dependent, except iDCs, whose influx from blood into spleen was blocked by the YopM-producing Y. pestis parent strain, but not the ΔyopM mutant. Ablation of PMNs, another main subset of Gr1+CCR2+ cells, relieved the growth limitation of the ΔyopM Y. pestis in liver, but not in spleen. Taken together, the data imply that YopM disables the recruitment of CCR2+Gr1+ iDCs into spleen but compromises the function of CCR2+Gr1+ PMNs in liver. These results were recapitulated when the infecting ambient-temperature-grown bacteria received 3 hours of incubation at 37°C. However, the appearance of the ΔyopM mutant phenotype was postponed at least 24 hours, indicating that some virulence property of Y. pestis that was induced by the temperature transition compensated for the loss of YopM in the ΔyopM strain at an early stage of the infection. In general, these findings provide a framework for focusing future research to identify YopM’s direct molecular targets.

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Burns, James Adam. "Cell adhesion molecule mechanisms for polymorphonuclear leukocyte (PMNL) recruitment to lung inflammation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0009/MQ60670.pdf.

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Bronnimann, Heather. "Functional Analysis of Interactions within the TCR-CD3-pMHC-CD4 Macro-complex." Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/612427.

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CD4⁺ T cells are a critical component of the adaptive immune compartment. Each T cell expresses a clonotypic T cell receptor (TCR) that must discriminate between self and foreign peptides presented in major histocompatibility molecules (pMHC) on the surface of antigen presenting cells to direct T cell fate decisions. Information regarding TCR-pMHC interactions must then be transmitted to the TCR-associated CD3 signaling modules, which contain ITAMs that serve as signaling substrates for Src kinases. The Src kinase, Lck, is recruited to the pMHC-bound TCR-CD3 complex via association with the CD4 coreceptor that binds MHCII. It is therefore through the coordinated interactions within the TCR-CD3-pMHC-CD4 macro-complex that productive TCR signaling can occur to inform T cell activation and fate decisions. While much is known regarding the structure of the individual subunits that make up the TCR-CD3-pMHC-CD4 macro-complex, there is little information regarding how these components come together to initiate TCR signaling and determine functional outcomes. Here, we have interrogated how interaction of these individual components leads to productive T cell activation. Specifically, we interrogated the nature of TCR-MHC interactions and provide evidence that there is intrinsic specificity of the TCR for MHCII. We have also built mouse models to determine the role of TCR-CD3 interactions and TCR dimerization in the transmission of information from the TCR to the CD3 subunits following TCR-pMHC engagement. Finally, we show that both the CD4 transmembrane and extracellular domains contribute to T cell activation in vitro. Overall, this work provides insight into how the constituents of the TCR-CD3-pMHC-CD4 macro-complex interact to initiate T cell fate and function.

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Donnelly, N. J. "Dielectric and electromechanical properties of PMN-PT thin films." Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426713.

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Lohman, Victor Lohman, and Tobias Borge. "Effektivisering av materiallager : En fallstudie på PMC Cylinders materiallager." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Industriell organisation och produktion, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-41863.

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To be a highly competitive company in today's market, it is important for companies to utilize their resources as efficiently as possible. Customers have high demands on price, quality, and delivery reliability and in order to meet the customers hard and growing demands, it is important for the companies to work with continuous improvements. A process where there are great opportunities for improvements is how companies work with their material handling. This means everything from storage and transportation to administrative operations. PMC Cylinders is a company located in Vaggeryd, which produces hydraulic cylinders in various sizes. In this thesis, a case study is done on one of their material storage to investigate whether the material handling in the storage can be more streamlined. A lot of resources is also tied up in the warehouse due to low sales of certain pipes. PCM wants to utilize the warehouse more effectively and get a better fill rate of essential material. The capital that is bound in the stock must be of material that has a high picking frequency. Some of the material in the warehouse has been there for so long that they are no longer used in their product range. There will be rust on several pipes as the layer is poorly insulated and moisture easily absorbs. This can lead to deterioration of quality of the material and disposal. To tackle this problem and to get more information, an ABC-analysis is made. An ABC-analysis aimed at dividing the material into different classes was conducted to investigate which material should be prioritized in the material handling. With the help of the ABC-analysis, 3 suggestions were proposed for a new article placement that should reduce time for material handling. It was also investigated if the material in the stock is relevant for PMC Cylinders products. This resulted in another suggestion. The suggestion indicated that the company was recommended to discard the material considered to be outdated. A calculation was made of how the change could affect the storage, it showed that agent stock level will decrease by 2.1% and the stock turnover will increase by 2.03% when discarding of the outdated material is performed.
För att vara ett högt konkurrerande företag i dagens marknad gäller det för företagen att utnyttja sina resurser så effektivt som möjligt. Kunderna har stora krav på pris, kvalitet, leveranssäkerhet och för att kunna möta kundernas hårda och växande krav gäller det att arbeta med ständiga förbättringar. En process där det kan finnas stora möjligheter till förbättring, är hur företag arbetar med deras materialhantering. Det innebär allt från lagerhållning och transportering till administrativa aktiviteter. PMC Cylinders är ett företag, lokaliserat i Vaggeryd, som producerar hydraulcylindrar i olika storlekar. I det här examensarbetet görs det en fallstudie på ett av deras materiallager för att undersöka om materialhanteringen i lagret kan effektiviseras. I dagsläget binds det även mycket kapital i rörlagret på grund av låg omsättning av vissa rör. PCM vill utnyttja lagret mer effektivt och få en bättre fyllnadsgrad av väsentligt material och därmed en högre omsättning i lagret, d.v.s. det kapital som binds i lagret ska vara av material som har en hög plockfrekvens. En del av materialet i lagret har funnits där så länge att de inte längre används i deras produktsortiment. Det uppstår rost på flera rör då lagret är dåligt isolerat och fukt tar sig lätt in. Detta kan leda till försämrad kvalitet av materialet och kassation. För att tackla det här problemet och för att få mer informations görs en ABC-analys. En ABC-analys som går ut på att dela upp materialet i olika klasser genomfördes för att undersöka vilket material som skall prioriteras i materialhanteringen. Med hjälp av ABC-analysen togs det fram tre åtgärdsförslag om en ny artikelplacering som bör reducera ledtiderna för plock av material i lagret. Det undersöktes även om materialet i lagret är aktuellt för PMC Cylinders produktsortiment. Detta resulterade i att ett åtgärdsförslag till togs fram. Åtgärdsförslaget innebar att företaget rekommenderades att kassera det material som anses vara inaktuellt. En beräkning gjordes på hur förändringen påverkar lagret och det visade att MLN minskar med 2,1% och LOH ökar med 2,03% då kassering av inaktuella produkter genomförs.

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Wennersten, Carl-Johan. "United Nations use of private military companies for peacekeeping operations." Thesis, Malmö universitet, Fakulteten för kultur och samhälle (KS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-23161.

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UN is sending peacekeeping operations all over the world. The paper will highlight that UN is not going only with their peacekeeping operation personnel, UN is also bringing private military companies into their ranks. This paper will focus on UN peacekeeping operations in Africa with the focus of non-interstate operations. Traditionally would not the Just war theory be the theory to apply to peacekeeping operations but by UN orthodox behavior of bringing private military contractors into peacekeeping operations, just war theory becomes appropriate. The purpose of this paper is to bring light on UN use of PMC and if PMC has increased UN security during peacekeeping operations. To be able to shed this light, a more extensive empirical study will be made to see UN practice with PMC by descriptive statistics. The paper finds that PMC has been an active force within peacekeeping operations and that PMC is performing several military tasks for UN. It further sees that UN fatalities are increasing in the cases when PMC has been present. Further insight into peacekeeping operation is that higher taxpaying nations are sending fewer troops and commanders compared to less taxpaying nations.

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Reed, Gary, and James DeVries. "TIMELY UPGRADES TO COMPLEX SYSTEMS SUCH AS THE TELEMETRY PROCESSING SYSTEM AT PMTC." International Foundation for Telemetering, 1990. http://hdl.handle.net/10150/613772.

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International Telemetering Conference Proceedings / October 29-November 02, 1990 / Riviera Hotel and Convention Center, Las Vegas, Nevada
The procurement of a new or upgraded data processing system doesn’t have to take eons of time and result in a less than adequate system. The complexity of requirements definition and system development are not getting any easier, but well-defined methodologies and the use of proven capabilities are providing a means of controlling the process. Even though there are more and more demands being placed on telemetry processing systems and advancing technology offers a myriad of solutions from which to choose, the Government and contractor communities are becoming more effective in applying techniques to define and deliver adequate systems. One method of demonstrating this is to describe an example of a complex telemetry processing system currently being developed for the Navy.

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24

Lin, Yu. "A Two-Mode Synchronous Buck Converter for Low-Power Devices with the Sleep Mode." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/72870.

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The power consumption of smart camera in car black box varies significantly between light load and heavy load. The high efficiency voltage regulator is necessary in prolong the life of smart camera battery. Since the smart camera only recording the video when car is driving, the most time of the smart camera works in the sleep mode. Hence the light load efficiency is important in this application, however, conventional buck converter usually have high efficiency at heavy load but poor efficiency at light load. To increase the light load efficiency of buck converter, this research continues Yeago's two phase buck converter with optimum phase selection control and Zhao's two mode buck converter to further improve the light load efficiency for the target application. With 5V input voltage and 1.2V output voltage, the proposed two-mode synchronous buck converter can supply the load power from 12mW to 1.44W. To improve the light load efficiency of conventional buck converter, the proposed design applied Wei's baby buck concept to provide another light load power stage to reduce the switching loss and driving loss at light load. Then, the variable frequency ripple-based constant on-time control with discontinuous conduction mode (DCM) in light load is applied to the baby-buck mode to reduce the switching frequency to further reduce the switching loss. Also, the baby-buck mode uses the synchronous buck topology to remove the diode in asynchronous converter to increase the efficiency at light load. Finally, a sensorless mode selector remove the sensing resistor in power stage to increase the efficiency for entire load range, especially for the heavy load. The mode selector can select the optimum mode for different load condition, and the opposite mode would completely shut down to save the loss. The proposed design is implement in CMOS 0.25um technology. The proposed monolithic buck converter which include the power stage of heavy buck mode, baby-buck mode and the controller is fabricated. The measurement result shows the close loop efficiency varies from 70%-83% toward the entire load range.
Master of Science

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25

GRIMOLIZZI, FRANCO. "Neutrophils alter placental glucose metabolism in gestational diabetes mellitus via neutrophil elastase mediated IRS1 degradation." Doctoral thesis, Università Politecnica delle Marche, 2017. http://hdl.handle.net/11566/245194.

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La gravidanza è da considerarsi una condizione pro-inflammatoria dove si osserva un’attivazione dei neutrofili circolanti. Con l'avanzare della gravidanza la concentrazione nel sangue di nucleosomi e mieloperossidasi aumenta e riflette la produzione delle trappole extracellulari dei neutrofili (NETs). Abbiamo dimostrato che in corso di diabete mellito gestazionale (GDM) tale produzione è aumentata in confronto ad una gravidanza fisiologica. Elevati livelli di glucosio e TNF-a, segni tipici presenti in corso di GDM, in vitro agiscono in modo sinergico e sono in grado di pre-attivare i neutrofili ed indurre il rilascio delle NETs. Abbiamo ipotizzato che, lo stato di iperattivazione osservato a livello sistemico possa essere associato ad una aumentata attività leucocitaria a livello placentare. A sostegno della nostra ipotesi, si osserva nei villi coriali isolati da placente GDM un’aumentata infiltrazione di PMNs pro-NETotici in associazione ad un accumulo della neutrofili elastasi (NE). Per valutare un possibile effetto pro-infiammatorio del glucosio a livello placentare, abbiamo incubato cellule di trofoblasto (BeWo) in presenza di un’elevata concentrazione di glucosio e successivamente valutato la produzione di TNF-a. È stato interessante rilevare un aumento nel rilascio di TNF- a tale da indurre un effetto pro-NETotico sui PMN con consequente rilascio della NE. Da recenti ricerche è emerso come in corso di diabete e tumore la NE possa essere internalizzata dalle cellule ed alterare la trasduzione del segnale insulinico attraverso la degradazione del substrato 1 del recettore insulinico (IRS1). Esperimenti in vitro hanno dimostrato che in presenza della NE si osserva una riduzione di IRS1 nelle cellule BeWo ed una diminuzione dell’internalizzazione del glucosio. Poichè l’espressione di IRS1 risulta ridotta nelle placente GDM é verosimile ipotizzare che la massiva presenza di NE ne può essere la causa. In conclusione, i nostri dati suggeriscono che in corso di GDM si verifica un’elevata produzione di NETs ed una massiva infiltrazione di pro-NETotici PMN nella placenta. Queste scoperte dimostrano come la NETosi abbia una significativa utilità diagnostica in corso di GDM e la NE un nuovo potenziale bersaglio terapeutico.
Human pregnancy is associated with a mild pro-inflammatory state characterized by activation of circulatory neutrophils (PMNs). Skewing of PMNs responses toward to neutrophil extracellular traps generation (NETs) is reflected in an increased of circulating nucleosomes and myeloperoxidase with advancing gestational age. Our data indicated that this pro-NETotic profile is enhanced in women with gestational diabetes mellitus (GDM). Maternal hyperglycemia and increased levels of TNF-a are a hallmark of GDM and we show a synergistic effect of both factors on the priming and release of NETs. Moreover, we hypothesized that systemic activation was associated with activated PMN in placenta. Indeed, we observed a massive infiltration of pro-NETotic PMNs and neutrophil elastase (NE) accumulation along chorionic villi of GDM placentas. To further explore whether hyperglycemia predisposes to exaggerated inflammatory response in placenta we incubated trophoblast BeWo cells in high glucose conditions and we next tested the TNF-a production capacity. Interestingly, TNF-a level was incresed and exert a pro-NETotic effect on PMN with consequent NE release. Recent studies in cancer tissues and diabetes models have described that released NE induce profound changes in the surrounding cells, altering the signal transducing cascade and promoting insulin resistance via degradation of insulin receptor substrate 1 (IRS1). Our in-vitro data indicate that addition of NE to trophoblast cell line BeWo causes degradation of IRS1 with consequent glucose uptake impairment. IRS1 is reduced in GDM placentas when compared to control placentas, suggesting that the presence of NE might be the causal factor. Taken together, our data showed that GDM is characterized by excessive NET formation and by a massive influx of pro-NETotic PMN into placentas. These findings underline the competence of NETs as a highly relevant diagnostic biomarker for GDM and NE as a new potential therapeutic target.

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Leland, Robert. "Duplicate Detection with PMC -- A Parallel Approach to Pattern Matching." Thesis, Norwegian University of Science and Technology, Department of Computer and Information Science, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9642.

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Fuzzy duplicate detection is an integral part of data cleansing. It consists of finding a set of duplicate records, correctly identifying the original or most representative record and removing the rest. The rate of Internet usage, and data availability and collectability is increasing so we get more and more access to data. A lot of this data is collected from, and entered by humans and this causes noise in the data from typing mistakes, spelling discrepancies, varying schemas, abbreviations, and more. Because of this data cleansing and approximate duplicate detection is now more important than ever. In fuzzy matching records are usually compared by measuring the edit distance between two records. This leads to problems with large data sets where there is a lot of record comparisons to be made so previous solutions have found ways to cut down on the amount of records to be compared. This is often done by creating a key which records are then sorted on with the intention of placing similar records near each other. There are several downsides to this, for example you need to sort and search through potentially large amounts of data several times to catch duplicate data accurately. This project differs in that it presents an approach to the problem which takes advantage of a multiple instruction stream, multiple data stream (MIMD) architecture called a Pattern Matching Chip (PMC), which allows large amounts of parallel character comparisons. This will allow you to do fuzzy matching against the entire data set very quickly, removing the need for clustering and re-arranging of the data which can often lead to omitted duplicates (false negatives). The main point of this paper will be to test the viability of this approach for duplicate detection, examining the performance, potential and scalability of the approach.

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Mietschke, Michael. "Zusammenhang zwischen Gefüge und ferroelektrischen Eigenschaften texturierter PMN-PT Dünnschichten." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-232546.

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Die Bedeutung von keramischen Materialien mit funktionalen Eigenschaften ist über die letzten Jahrzehnte kontinuierlich gestiegen. Ein besonderes Interesse liegt dabei in der elektronischen Speicherung von Informationen. Die Realisierung war jedoch lange Zeit problematisch, da die erforderlichen Feldstärken, die notwendig sind, um die Polarisation zu schalten, für Massivmaterialien zu hoch sind. Heutzutage ist dies dank moderner Dünnschichttechnologien kein Problem mehr, so dass nichtflüchtige ferroelektrische Datenspeicher kommerziell verfügbar sind. Aufgrund der ausgezeichneten dielektrischen und elektromechanischen Eigenschaften von ferroelektrischen Materialien werden diese auch für Anwendungen in Aktuatoren, Kondensatoren oder mikro-elektro-mechanischen Systemen verwendet. Neben den klassischen Ferroelektrika wie Pb(Zr,Ti)O3 spielen dabei vor allem Relaxor-Ferroelektrika wie Pb(Mg1/3Nb2/3O3-PbTiO3 (PMN-PT) eine entscheidende Rolle. Eine weitere sehr interessante funktionale Eigenschaft von ferroelektrischen Materialien, die besonders in den letzten zehn Jahren das Forschungsinteresse geweckt hat, ist der elektrokalorische Effekt (electro caloric effect, ECE). Besonders hohe ECE konnten in der Vergangenheit mit Blei-basierenden Materialien, wie beispielsweise PMN-PT, erzielt werden. Um den Einfluss der Struktur auf die funktionalen Eigenschaften zu untersuchen ist es vorteilhaft, mit texturierten Schichten zu arbeiten. Als Materialsystem wurde in dieser Arbeit PMN-PT verwendet, da dieses besonders gute ferroelektrische und elektrokalorischen Eigenschaften zeigt und es aufgrund der vielfältigen veröffentlichten Untersuchungen als Modellsystem genutzt werden kann. Als geeignete Herstellungsmethode von Dünnschichten komplexer Oxide hat sich die gepulste Laserabscheidung herausgestellt, die auch in dieser Arbeit genutzt wurde. Die Schwerpunkte der strukturellen Untersuchungen beschäftigen sich mit der Stabilisierung der Perowskit-Phase des PMN-PT, der detaillierten Aufklärung des Gefüges sowie der Realisierung von Schichten mit unterschiedlicher Orientierung und auf verschiedenen Substratmaterialien. Hinsichtlich der funktionalen Eigenschaften wird auf den Einfluss der Pyrochlor-Phase auf die Ferroelektrizität, die Anisotropie der ferroelektrischen und elektrokalorischen Eigenschaften sowie auf eine Möglichkeit der direkten Messung der elektrokalorischen Temperaturänderung von PMN-PT Dünnschichten eingegangen.

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28

Felix, Anderson André [UNESP]. "Estudo da estabilização da fase perovskita PMN em filmes ultrafinos." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/92014.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O presente trabalho descreve os estudos realizados para a síntese de filmes ferroelétricos ultrafinos de Pb(Mg1/3Nb2/3)O3 (PMN) e o estudo sistemático da cinética de cristalização deste material visando a obtenção de filmes monofásicos. Os filmes foram produzidos a partir da modificação de um método químico baseado em precursores óxidos. A obtenção dos filmes de PMN se deu através de uma técnica de duplo estágio, que possibilita maior controle na supressão de fases pirocloro, e da técnica via Método dos Precursores Óxidos (MPO), através da reação direta dos óxidos. Filmes de PMN foram preparados sobre substratos Si(100) com diferentes números de deposições. Esses filmes foram submetidos a tratamentos térmicos entre 400oC e 800ºC, em forno convencional, sob diferentes condições de preparo. A estrutura dos filmes foi investigada pela técnica de difração de raios-X e refinamentos da estrutura pelo método de Rietveld. Os resultados apresentaram uma coexistência da fase pirocloro Pb1.86Mg0.24Nb1.76O6.5 e da fase perovskita Pb(Mg1/3Nb2/3)O3 (PMN) nos filmes preparados via rota da Columbita e a supressão da fase prirocloro nos filmes preparados pelo método MPO. Um estudo da morfologia por MEV indicou a preparação de filmes com boa homogeinidade e espessura média de 150nm Os resultados obtidos neste projeto indicam que a estabilização da fase perovkita do PMN e a supressão da fase pirocloro está relacionada a uma combinação particular de parâmetros tais como tempo e temperatura de cristalização e a adição de excessos de MgO e PbO a estequiometria.
The present work describes the studies for the synthesis of ultrathin ferroelectric films of Pb(Mg1/3Nb2/3)O3 (PMN) and the systematic study of the crystallization kinetics of this material aimed at obtaining singlephase films. The films were produced from the modification of a chemical method based on oxide precursors. The obtention of the PMN films made by a technique of double stage, that allows greater control in the suppression of pyrochlore phases, and by technique via Oxide Precursors Method(OPM), through a direct reaction of the oxides. PMN films were prepared on Si(100) substrates with different numbers of depositions. These films were subjected to thermal treatments between 400ºC and 800°C, in conventional oven, under different preparation conditions. The structure of the films was investigated by the technique of X-ray diffraction and the structures refinements by the Rietveld method. The results showed a coexistence of pyrochlore phase Pb1.86Mg0.24Nb1.76O6.5 and perovskite phase Pb(Mg1/3Nb2/3)O3(PMN) in the films prepared via Columbita route and suppression of pyrochlore phase in films prepared by the OPM method. A study of morphology by SEM indicated the preparation of films with good homogeneity and medium thickness of 150 nm. The results obtained in this project suggest that the stabilization of PMN phase perovkite and the suppression of the pyrochlore phase is related to a particular combination of parameters such as time and temperature of crystallization and the addition of excess of MgO and PbO in the stoichiometry.

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29

Reis, Reginaldo Naves dos [UNESP]. "Síntese e propriedades físicas de cerâmicas ferroelétricas de PMN-PT." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/102529.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Materiais ferroelétricos do sistema Pb('Mg IND. 1/3''Nb IND.2/3')'O IND. 3'-xPbTi'O IND. 3'(PMN-xPT), possuem potencial efetivo para aplicações em dispositivos eletromecânicos, tais como, transdutores e sensores. Porém, a obtenção de cerâmica de PMN-xPT livre de fase pirocloro (paraelétrica) exige rigoroso controle durante a síntese. Neste trabalho, as condições destinadas a supressão de fase pirocloro em cerâmicas de PMN e PMN-xPT (para x = 0,33, 0,35 e 0,37), foram estudadas a partir de uma nova rota de preparação em função do excesso de MgO e PbO. Paralelamente, cerâmicas de PMN e PMN-PT obtidas pela rota convencional de mistura de óxidos, foram preparadas e os resultados comparados. Os resultados obtidos revelaram valores mais elevados de permissividade para as cerâmicas preparadas pela nova rota. Os valores da polarização remanescente das cerâmicas de PMN-xPT mostraram-se comparáveis com monocristais. Medidas dielétricas realizadas nas cerâmicas de PMN-xPT apontam um significante aumento nos valores de permissividade dielétrica em função do aumento do campo elétrico AC. Condutividade AC e impedância nas cerâmicas de PMN-xT foram estudadaas na região de frequência de 100Hz-1MHz e temperatura 325 - 50ºC. Uma anomalia no espectro de condutividade foi observada para todas as composições, próximo ao ponto de transição de fase ferroelétrica-paraelétrica.
Ferroelectric materials of Pb('Mg IND. 1/3''Nb IND.2/3')'O IND. 3'-xPbTi'O IND. 3'(PMN-xPT) system have effective potential for applications in electromechanical devices such as transducers and sensors. However, to obtain free pyrochlore phase (paraelectric) ceramics of PMN-xPT requires control during the synthesis. In this work, the conditions for the removal of pyrochlore phase of PMN and PMN-xPT (for x = 0.33, 0,35 and 0.37) ceramics, were studied using a new route of preparation with the excess MgO and PbO. The obtained results were compared with the ceramics of PMN and PMN-xPT prepared by the conventional route of mixed oxides. The results showed higher values of permittivity for the ceramics prepared by the new route. The remnant polarization values of PMN-xPT ceramics shown to be comparable with single crystal. Dielectric of PMN-xPT ceramics showed a significant increase in the values of dielectric permittivity due to the increase of the AC electric field. Conductivity AC and impedance of PMN-xPT ceramics were studied in the frequency range of 100Hz - 1MHz and temperature 325 - 50ºC. An anomaly was observed in the spectrum of conductivity for all the compositions, which is close to the point of ferroelectric-paraelectric phase transition.

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30

McPhillips, John. "Assessment pf PMN-PT thin films for acoustic device applications." Thesis, Queen's University Belfast, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437482.

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31

Felix, Anderson André. "Estudo da estabilização da fase perovskita PMN em filmes ultrafinos /." Ilha Solteira : [s.n.], 2009. http://hdl.handle.net/11449/92014.

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Orientador: Eudes Borges de Araújo
Banca: João Carlos Silos Moraes
Banca: Adolfo Franco Júnior
Resumo: O presente trabalho descreve os estudos realizados para a síntese de filmes ferroelétricos ultrafinos de Pb(Mg1/3Nb2/3)O3 (PMN) e o estudo sistemático da cinética de cristalização deste material visando a obtenção de filmes monofásicos. Os filmes foram produzidos a partir da modificação de um método químico baseado em precursores óxidos. A obtenção dos filmes de PMN se deu através de uma técnica de duplo estágio, que possibilita maior controle na supressão de fases pirocloro, e da técnica via Método dos Precursores Óxidos (MPO), através da reação direta dos óxidos. Filmes de PMN foram preparados sobre substratos Si(100) com diferentes números de deposições. Esses filmes foram submetidos a tratamentos térmicos entre 400oC e 800ºC, em forno convencional, sob diferentes condições de preparo. A estrutura dos filmes foi investigada pela técnica de difração de raios-X e refinamentos da estrutura pelo método de Rietveld. Os resultados apresentaram uma coexistência da fase pirocloro Pb1.86Mg0.24Nb1.76O6.5 e da fase perovskita Pb(Mg1/3Nb2/3)O3 (PMN) nos filmes preparados via rota da Columbita e a supressão da fase prirocloro nos filmes preparados pelo método MPO. Um estudo da morfologia por MEV indicou a preparação de filmes com boa homogeinidade e espessura média de 150nm Os resultados obtidos neste projeto indicam que a estabilização da fase perovkita do PMN e a supressão da fase pirocloro está relacionada a uma combinação particular de parâmetros tais como tempo e temperatura de cristalização e a adição de excessos de MgO e PbO a estequiometria.
Abstract: The present work describes the studies for the synthesis of ultrathin ferroelectric films of Pb(Mg1/3Nb2/3)O3 (PMN) and the systematic study of the crystallization kinetics of this material aimed at obtaining singlephase films. The films were produced from the modification of a chemical method based on oxide precursors. The obtention of the PMN films made by a technique of double stage, that allows greater control in the suppression of pyrochlore phases, and by technique via Oxide Precursors Method(OPM), through a direct reaction of the oxides. PMN films were prepared on Si(100) substrates with different numbers of depositions. These films were subjected to thermal treatments between 400ºC and 800°C, in conventional oven, under different preparation conditions. The structure of the films was investigated by the technique of X-ray diffraction and the structures refinements by the Rietveld method. The results showed a coexistence of pyrochlore phase Pb1.86Mg0.24Nb1.76O6.5 and perovskite phase Pb(Mg1/3Nb2/3)O3(PMN) in the films prepared via Columbita route and suppression of pyrochlore phase in films prepared by the OPM method. A study of morphology by SEM indicated the preparation of films with good homogeneity and medium thickness of 150 nm. The results obtained in this project suggest that the stabilization of PMN phase perovkite and the suppression of the pyrochlore phase is related to a particular combination of parameters such as time and temperature of crystallization and the addition of excess of MgO and PbO in the stoichiometry.
Mestre

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32

Reis, Reginaldo Naves dos. "Síntese e propriedades físicas de cerâmicas ferroelétricas de PMN-PT /." Ilha Solteira, 2009. http://hdl.handle.net/11449/102529.

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Orientador: Eudes Borges de Araújo
Banca: Newton Luiz Dias Filho
Banca: Marcelo Rubens Barsi Andreeta
Banca: Fábio Simões de Vicente
Banca: Emerson Marcelo Girotto
O Programa de Pós-Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi da Unesp
Resumo: Materiais ferroelétricos do sistema Pb('Mg IND. 1/3'Nb IND.2/3')'O IND. 3'-xPbTi'O IND. 3'(PMN-xPT), possuem potencial efetivo para aplicações em dispositivos eletromecânicos, tais como, transdutores e sensores. Porém, a obtenção de cerâmica de PMN-xPT livre de fase pirocloro (paraelétrica) exige rigoroso controle durante a síntese. Neste trabalho, as condições destinadas a supressão de fase pirocloro em cerâmicas de PMN e PMN-xPT (para x = 0,33, 0,35 e 0,37), foram estudadas a partir de uma nova rota de preparação em função do excesso de MgO e PbO. Paralelamente, cerâmicas de PMN e PMN-PT obtidas pela rota convencional de mistura de óxidos, foram preparadas e os resultados comparados. Os resultados obtidos revelaram valores mais elevados de permissividade para as cerâmicas preparadas pela nova rota. Os valores da polarização remanescente das cerâmicas de PMN-xPT mostraram-se comparáveis com monocristais. Medidas dielétricas realizadas nas cerâmicas de PMN-xPT apontam um significante aumento nos valores de permissividade dielétrica em função do aumento do campo elétrico AC. Condutividade AC e impedância nas cerâmicas de PMN-xT foram estudadaas na região de frequência de 100Hz-1MHz e temperatura 325 - 50ºC. Uma anomalia no espectro de condutividade foi observada para todas as composições, próximo ao ponto de transição de fase ferroelétrica-paraelétrica.
Abstract: Ferroelectric materials of Pb('Mg IND. 1/3'Nb IND.2/3')'O IND. 3'-xPbTi'O IND. 3'(PMN-xPT) system have effective potential for applications in electromechanical devices such as transducers and sensors. However, to obtain free pyrochlore phase (paraelectric) ceramics of PMN-xPT requires control during the synthesis. In this work, the conditions for the removal of pyrochlore phase of PMN and PMN-xPT (for x = 0.33, 0,35 and 0.37) ceramics, were studied using a new route of preparation with the excess MgO and PbO. The obtained results were compared with the ceramics of PMN and PMN-xPT prepared by the conventional route of mixed oxides. The results showed higher values of permittivity for the ceramics prepared by the new route. The remnant polarization values of PMN-xPT ceramics shown to be comparable with single crystal. Dielectric of PMN-xPT ceramics showed a significant increase in the values of dielectric permittivity due to the increase of the AC electric field. Conductivity AC and impedance of PMN-xPT ceramics were studied in the frequency range of 100Hz - 1MHz and temperature 325 - 50ºC. An anomaly was observed in the spectrum of conductivity for all the compositions, which is close to the point of ferroelectric-paraelectric phase transition.
Doutor

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Droescher, Roberta Elisabeth. "Obtenção e caracterização microestrutural e elétrica de cerâmicas PZT-PMN." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/17559.

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Este trabalho investigou o sistema (1 - x )PZT - x PMN, avaliando a influência da composição química e dos parâmetros de sinterização na microestrutura e propriedades elétricas dos corpos cerâmicos obtidos pelo método convencional de mistura de óxidos. Os óxidos usados foram o Nb2O5, ZrO2, TiO2, PbO e MgCO3, cominuídos e homogeneizados em moinho de bolas, por 3 horas. Para o 0,65PZT - 0,35PMN, utilizou-se 28,58% de Nb2O5, 38,93% de ZrO2, 23,29% de TiO2 e 9,2% de MgCO3; para o 0,75PZT-0,25PMN, utilizou-se 20,9% de Nb2O5, 45,34% de ZrO2, 27,13% de TiO2 e 6,62% de MgCO3 e para o 0,85PZT-0,15PMN, usa-se 12,71% de Nb2O5, 52,09% de ZrO2, 31,16% de TiO2 e 4,04% de MgCO3. O pó obtido foi submetido a calcinação a 1200°C por 4 h e, então, acrescentado PbO com um excesso de 2% em massa.à mistura, a qual foi submetida a uma nova calcinação a 800°C durante 2 horas. O pó resultante da calcinação foi conformado por prensagem, utilizando uma prensa uniaxial a 190 MPa, na forma de discos medindo 10 mm de diâmetro e 1,5 mm de espessura. A curva de queima dos corpos cerâmicos consistiu em um novo patamar a 500°C por 4h (e/ou a 800°C por 2h) e outro consecutivo a 1200°C por 4h. As amostras foram caracterizadas pela sua densidade e porosidade aparente (método de Arquimedes), composição de fases (por difração de raio-X), Microscopia Eletrônica de Varredura (MEV) e caracterização elétrica (constante dielétrica e capacitância). Os corpos cerâmicos correspondentes à composição 0,75PZT-0,25PMN alcançaram a maior densidade (7,09 ± 0,18 g/cm³) quando calcinados sucessivamente a 500°C e a 800°C, com os maiores valores de capacitância (210 pF a 200 KHz) e de constante dielétrica (1000 na frequência de 1 KHz), com menor evidência de formação de pirocloro e maior de perovskita. Os valores de constante dielétrica encontrados estão dentro do esperado para materiais cerâmicos piezoelétricos do tipo PZT - PMN, aproximadamente 1000 para freqüências de 1KHz.
This work investigated the system (1 - x )PZT - x PMN, evaluating the influence of the chemical composition and the sintering parameters on the microstructure and the electric properties of ceramic bodies obtained by the conventional method of mixture of oxides. The used oxides were Nb2O5, ZrO2, TiO2, PbO e MgCO3, squeezed and homogenized in mill of balls, for 3 hours. For the 0.65PZT-0.35PMN, it was used 28.58% of Nb2O5, 38.93% of ZrO2, 23.29% of TiO2 and 9.2% of MgCO3; for the 0.75PZT-0.25PMN, it was used 20.9% of Nb2O5, 45.34% of ZrO2, 27.13% of TiO2 and 6.62% of MgCO3 and for the 0.85PZT-0.15PMN, it is used 12.71% of Nb2O5, 52.09% of ZrO2, 31.16% of TiO2 and 4.04% of MgCO3. The obtained powder was submitted the calcination for 1200°C for 4 h and, then, increased PbO with an excess of 2% in mass, which was submitted to a new calcination to 800°C for 2 hours. The calcinated powder was conformed by pressing, using a uniaxial press to 190 MPa, in the form of disks measuring a diameter of 10mm and 1.5 mm of thickness. The curve of the burning of the ceramic bodies consisted in a new calcination to 500°C for 4h (and/or to 800°C for 2h) and other consecutive to 1200°C for 4h. The samples were characterized by density and apparent porosity (Method of Arquimedes), composition of phases (by X - rays diffraction), Scanning Electric Microstructure (SEM) and electrical properties characterization (dielectric constant and capacitance). The ceramic bodies corresponding to the composition 0.75PZT-0.25PMN reached the largest density (7.09 ± 0.18 g/cm³) when calcined successively to 500°C and 800°C, with the largest values of capacitance (210 pF to 200 KHz) and dielectric constant (1000 in the frequency of 1 KHz), with smaller evidence of pyrochlore formation and larger of perovskte. The values of dielectric constant found are inside of the expected for the piezoelectric ceramics of the type PZT- PMN, approximately 1000 by frequencies of 1KHz.

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Ciubotariu, Dragos. "Design, Modeling, Fabrication and Control of PMN-PT Piezoelectric Systems." Thesis, Besançon, 2016. http://www.theses.fr/2016BESA2048/document.

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Ce travail propose l’utilisation d’un nouveau matériau, appelé PMN-PT, qui continue aider la miniaturisation des systèmes complexes, utilisés dans des différentes technologies. Le travail est présenté dans le cadre de collaboration entre deux projets, MIOP et ADMAN. Les besoins tient compte que les actionneurs soient capables de délivrer de haute déplacement tout en conservant la simplicité et la fiabilité du système. L’accent est mis sur la polyvalence de ce matériau piézo-électrique, PMN-PT, en raison de ses propriétés électro-mécanique. Le travail comprend un aperçu sur quoi influence les propriétés électro-mécaniques du PMN-PT. L’accent est mis sur deux différentes, mais très puissants coupes: anisotrope [011] et longitudinale [001], choisi pour grand déplacement et haute dynamique avec un volume petit. Pour le PMN-PT[001], une structure de type poutre a été étudié, avec un modèle amélioré pour prendre en compte les spécificités de matériel. Les déplacements et forces ont été trouvés d’ être supérieur `a un actionneur en PZT, similairement dimensionnée, tandis que avoir des non-linéarités réduites. Ceci est illustré avec une micro pince avec 6DDL. L’étude de PMN-PT [001] coupé longitudinal suit. Cette étude a été fait en utilisant PMNPT comme un actionneur avec une structure simple, facile à intégrer. Les résultats démontrent les améliorations PMN-PT peut apporter à micro-spectrométrie et la correction d’image avec des micromiroirmobiles. Un micro actionneur PMN-PT a été intégré dans une structure compatible avec des MOEMS et présenté
This work proposes the use of a novel material, called PMN-PT, that futher aids the miniaturizationof complex systems used in different technologies. The work is presented within the collaborativeframework of two projects, MIOP and ADMAN. The end-needs account for actuators capable ofdelivering high displacement, while maintaining system simplicity and reliability. The focus is onthe versatility of the PMN-PT piezoelectric material, due to its electro-mechanical properties. Thework includes an overview on what influences the electro-mechanical properties focusing on twodifferent, though very potent cuts: anisotropic [011] and longitudinal [001]. They were chosen forgenerating large displacement and high dynamics with small volume. For PMN-PT[001] a cantileverstructure was studied, for which the model was improved taking into account the material specificities.Displacements and forces were found to be superior to a similarly dimensioned PZT actuator, whilsthaving reduced non-linearities. This is exemplified with a 6 DoF capable microgripper. The PMNPT[001] longitudinal cut based actuator study follows. This is done by using PMN-PT as a simple,easy to integrate, bulk actuator. The findings demonstrate the improvements PMN-PT can bringto micro-spectrometry and image correction with micro-mirror displacement. A bulk PMN-PT microactuator was integrated into a MOEMS compatible structure and presented

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Luo, Hongyu Shih Wei-Heng Shih Wan Y. "Colloidal processing of PMN-PT thick films for piezoelectric sensor applications /." Philadelphia, Pa. : Drexel University, 2005. http://dspace.library.drexel.edu/handle/1860/500.

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Fujino, Roberto Takashi [UNESP]. "Transições de fases estruturais em cerâmicas ferroelétricas do sistema PMN-PT." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/91995.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A solução sólida (1-x) Pb (Mg1/3Nb2/3)O3-PbTiO3 (PMN-xPT) é um ferroelétrico relaxor conhecido pelos altos valores de constante dielétrica e coeficientes piezelétricos. Devido a essas propriedades, o sistema PMN-xPT tem sido intensamente estudado nos últimos anos com potenciais aplicações em diferentes setores da tecnologia. O presente trabalho apresenta o estudo de transições de fases estruturais na solução sólida ferroelétrica 0,70Pb(Mn1/3Nb2/3)O3-0,30PbTiO3 (PMN-30PT) e 0,65Pb(Mn1/3Nb2/3)O3-0,35PbTiO3 (PMN-35PT). À temperatura ambiente, cerâmicas de PMN-xPT apresentam várias estruturas dependendo da quantidade de titanato de chumbo (PT): romboédrica (x<0,30) ou ainda monoclínica do tipo MB (0,270,34). A separação entre a fase romboédrica e a fase tetragonal é denominada de Contorno de Fase Morfotrópico (Morphotropic Phase Boundary-MPB) onde recentemente foi descoberta uma nova fase monoclínica, que pode estar relacionado com os altos valores piezelétricos desse sistema. Nos últimos anos, vários trabalhos foram publicados sobre o MPB, algumas novas características foram propostas por Noheda et al e Singh e Pandey utilizando técnicas de difratometria de pó com radiação síncrotron de alta resolução e medidas dielétricas...
The solid solution (1-x) Pb (Mg1/3Nb2/3)O3-xPbTiO3 (PMN-xPT) is a relaxor ferroelectric known by the high values of dielectric constant and piezoelectric coefficients. Had to these properties, the PMN-xPT system has been intensely studied in recent years with potential applications in different sectors of the technology. The present work show the study of structural phases transitions in the ferroelectric solid solution 0,70Pb (Mn1/3Nb2/3)O3-0,35PbTiO3 (PMN-30PT) and 0,65Pb (Mn1/3Nb2/3) O3-0,35PbTiO3 (PMN-35PT). At room temperature, ceramic of PMN-PT presents some structures depending on the amount of titanate of lead (PT): romboédral (x<0,30), monoclinic of the type MB (0,270,34). The separation between the romboédral phase and the tetragonal phase is called of (Morphotropic Phase Boundary-MPB) where recently was discovered a new monoclinic phase, that can be related with the high piezoelectric values of this system. In recent years, some works come being published on the MPB, some new characteristics had been proposals for Noheda et al and Singh and Pandey using powder x-ray diffractions with high resolution síncrotron radiation and dielectric measures in the neighborhoods of the MPB. With the use of the technique of infrared... (Complete abstract click electronic access below)

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Fujino, Roberto Takashi. "Transições de fases estruturais em cerâmicas ferroelétricas do sistema PMN-PT /." Ilha Solteira : [s.n.], 2006. http://hdl.handle.net/11449/91995.

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Orientador: Eudes Borges de Araújo
Banca: Keizo Yukimitu
Banca: Alejandro Pedro Ayala
Resumo: A solução sólida (1-x) Pb (Mg1/3Nb2/3)O3-PbTiO3 (PMN-xPT) é um ferroelétrico relaxor conhecido pelos altos valores de constante dielétrica e coeficientes piezelétricos. Devido a essas propriedades, o sistema PMN-xPT tem sido intensamente estudado nos últimos anos com potenciais aplicações em diferentes setores da tecnologia. O presente trabalho apresenta o estudo de transições de fases estruturais na solução sólida ferroelétrica 0,70Pb(Mn1/3Nb2/3)O3-0,30PbTiO3 (PMN-30PT) e 0,65Pb(Mn1/3Nb2/3)O3-0,35PbTiO3 (PMN-35PT). À temperatura ambiente, cerâmicas de PMN-xPT apresentam várias estruturas dependendo da quantidade de titanato de chumbo (PT): romboédrica (x<0,30) ou ainda monoclínica do tipo MB (0,270,34). A separação entre a fase romboédrica e a fase tetragonal é denominada de Contorno de Fase Morfotrópico (Morphotropic Phase Boundary-MPB) onde recentemente foi descoberta uma nova fase monoclínica, que pode estar relacionado com os altos valores piezelétricos desse sistema. Nos últimos anos, vários trabalhos foram publicados sobre o MPB, algumas novas características foram propostas por Noheda et al e Singh e Pandey utilizando técnicas de difratometria de pó com radiação síncrotron de alta resolução e medidas dielétricas... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The solid solution (1-x) Pb (Mg1/3Nb2/3)O3-xPbTiO3 (PMN-xPT) is a relaxor ferroelectric known by the high values of dielectric constant and piezoelectric coefficients. Had to these properties, the PMN-xPT system has been intensely studied in recent years with potential applications in different sectors of the technology. The present work show the study of structural phases transitions in the ferroelectric solid solution 0,70Pb (Mn1/3Nb2/3)O3-0,35PbTiO3 (PMN-30PT) and 0,65Pb (Mn1/3Nb2/3) O3-0,35PbTiO3 (PMN-35PT). At room temperature, ceramic of PMN-PT presents some structures depending on the amount of titanate of lead (PT): romboédral (x<0,30), monoclinic of the type MB (0,270,34). The separation between the romboédral phase and the tetragonal phase is called of (Morphotropic Phase Boundary-MPB) where recently was discovered a new monoclinic phase, that can be related with the high piezoelectric values of this system. In recent years, some works come being published on the MPB, some new characteristics had been proposals for Noheda et al and Singh and Pandey using powder x-ray diffractions with high resolution síncrotron radiation and dielectric measures in the neighborhoods of the MPB. With the use of the technique of infrared... (Complete abstract click electronic access below)
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38

Leblebicioglu, Binnaz. "The susceptibility of human PMNs to inhibition by extracellular pH shifts and signal transduction antagonists /." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu148795015360262.

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Almeida, Leslie Avila do Brasil. "Avaliação de tratamento homeopático com Phytolacca decandra 30CH durante a lactação de vacas com mastite subclínica." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-20072009-130359/.

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O elevado custo dos tratamentos tradicionais da mastite bovina, associado à redução de produção e inviabilidade de tratamento das mastites subclínicas durante a lactação, bem como a exigência cada vez mais rigorosa da ausência de resíduos de antimicrobianos por parte de instituições nacionais e internacionais, impulsiona o desenvolvimento de novas alternativas terapêuticas que visem minimizar o impacto das medidas tradicionais de tratamento. A homeopatia surge como importante alternativa, sendo aceita nacional e internacionalmente. O objetivo do trabalho foi avaliar o tratamento homeopático com Phytolacca decandra 30CH durante a lactação de vacas com mastite subclínica, utilizando parâmetros de qualidade do leite como Califórnia Mastitis Test (CMT), contagem de células somáticas (CCS) totais, porcentagens de polimorfonucleares (PMN) e de mononucleares (MN), teores de proteína, lactose, gordura, sólidos totais (ST) e extrato seco desengordurado (ESD), além da mensuração da produção leiteira. Foram selecionadas 26 vacas, CMT 2+ e 3+ sem sinais de mastite clínica, entre o terceiro e sexto mês de lactação, pluríparas e divididas em dois grupos, um com tratamentos medicamentosos mensais e outro com tratamentos quinzenais. Mensalmente foram colhidas duas amostras de leite de cada glândula mamária (teto) que apresentava mastite subclínica. Uma das amostras foi utilizada para CCS e análise dos componentes do leite, e a outra para identificação microbiológica. Nos grupos tratados, foi administrado o medicamento homeopático Phytolaca decandra 30CH diluído em água e aspergido nas mucosas oro-nasais e vaginais, enquanto que nos grupos denominados controle foi administrado placebo da mesma maneira. A pesagem da produção láctea de ambos os grupos foi realizada quinzenalmente até o final do experimento. Verificou-se então que não houve diferença significativa entre a produção láctea, CCS e a presença de microrganismos na secreção láctea das glândulas quando comparadas antes e depois do tratamento homeopático, dentro de cada grupo, bem como quando comparados os grupos entre si. As medianas de CMT e porcentagens de PMN foram compatíveis com infecções mamárias agudas, embora os animais tenham sido diagnosticados como portadores de mastites crônicas e em nenhum momento desenvolveram sinais clínicos.
The high cost of traditional treatments of bovine mastitis, with the reduction of production and impracticable treatment of subclinical mastitis during lactation, as well as the requirement of an increased demand for absence of antimicrobial agents residues by national and international institutions, drives the development of new therapeutic alternatives in order to minimizing the impact of traditional treatment measures. The homeopathy appears as an important alternative, accepted domestically and internationally. The objective of this work was to evaluate homeopathic treatment with Phytolacca decandra 30CH during the lactation of cows with subclinical mastitis, using some milk quality parameters as California Mastitis Test (CMT), total somatic cell count (SCC), percentages of polymorphonuclear (PMN) and mononuclear (MN) cells, levels of protein, lactose, fat, total solids and dry defatted matter, in addition to the measurement of milk production. Twenty-six cows were selected with CMT 2 + and 3 + without any signs of clinical mastitis, between the third and sixth month of lactation, pluriparous and they were divided into two groups, with monthly or biweekly drug treatments. Monthly were collected two milk samples from each mammary gland (teat) that presented subclinical mastitis. One of the samples was used for analysis of SCC and milk components, and the other one for microbiological identification. In the treated groups, was given the homeopathic medicine Phytolaca decandra 30CH diluted in water and sprayed in the oral-nasal and vaginal mucosa, while to the control group was given placebo following the same method. The weighing of the milk production for both groups was performed fortnightly until the end of the experiment. There was no significant difference between milk production, SCC and the presence of microorganisms in milk gland secretion compared before and after homeopathic treatment, within each group as well as comparing the groups together. The medians of CMT and percentages of PMN were compatible with acute mammary infection, in spite of they have been diagnosed as carriers of chronic mastitis, and at any time no clinical signs have been developed.

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Sakiyama, Débora Tieko Parlato. "Avaliação dos medicamentos homeopáticos Sulphur 30CH e Calcarea carbonica 30CH para tratamento de vacas com mastite subclínica." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/10/10134/tde-16022011-140712/.

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O uso de antibióticos para tratamento da mastite bovina subclínica durante a lactação apresenta restrições econômicas e a administração indiscriminada e inadequada destes medicamentos os torna potencialmente tóxicos aos animais e aos consumidores finais dos produtos lácteos. A utilização de medicamentos homeopáticos oferece menor custo, facilidade de administração, não há risco de resistência microbiana e não é necessário o descarte do leite dos animais em tratamento. Além disso, a homeopatia é reconhecida no Brasil como especialidade médica veterinária e aceita para uso no sistema de produção animal orgânico. Portanto, o presente trabalho teve como objetivo avaliar a eficácia de dois protocolos homeopáticos para tratamento da mastite bovina subclínica durante a lactação. O experimento foi realizado no período de seis meses e dividido em duas etapas. Na Etapa I, um grupo foi medicado com Sulphur 30CH, enquanto que o outro recebeu placebo. Na Etapa II, um grupo foi medicado com Calcarea carbonica 30CH e o outro grupo recebeu placebo. Os medicamentos foram administrados a cada trinta dias na Etapa I e a cada quinze dias na Etapa II. Em cada etapa foram coletadas amostras de leite antes, durante e após o tratamento. Para avaliar a eficácia dos protocolos, durante o experimento foram analisadas 138 amostras de leite na Etapa I e 72 amostras na Etapa II, realizando-se prova de Tamis, California Mastitis Test (CMT), contagem de células somáticas (CCS), quantificação de polimorfonucleares (PMN) e mononucleares (MN) por microscopia óptica, exame microbiológico e mensuração da produção leiteira. As análises estatísticas foram realizadas utilizando o software Graphpad Instat 1990-93. Os protocolos homeopáticos testados não diminuíram a celularidade do leite, pois não houve diferenças significativas nos resultados do CMT e da CCS no decorrer do experimento. Também não foi constatada nenhuma alteração significante na produção láctea. O microrganismo isolado com maior frequência no rebanho estudado foi o Corynebacterium bovis. Porém, não houve diferenças significativas em relação à frequência de isolamento deste microrganismo ao longo dos tratamentos, indicando a sua permanência nas glândulas mamárias. Além disso, observou-se durante todo o experimento o predomínio de células PMN em relação às MN. Sugere-se o estudo de novos protocolos homeopáticos com outros medicamentos, potência e frequência de administração, a fim de buscar alternativas para o tratamento de vacas com mastite subclínica
The use of antibiotics for treatment of bovine subclinical mastitis during lactation presents economic restrictions and the indiscriminate and inappropriate administration of these drugs makes them potentially toxic to animals and consumers of dairy products. The use of homeopathic medicine offers lower cost, ease of administration, no risk of microbial resistance and is not necessary to discard milk from animals under treatment. Furthermore, homeopathy is recognized as a medical specialty in Brazil and support for veterinary use in organic livestock production system. Therefore, this study aimed to evaluate the effectiveness of two protocols for homeopathic treatment of bovine subclinical mastitis during lactation. The experiment was performed between six months and divided into two stages. In Phase I, one group was treated with Sulphur 30CH, while the other received placebo. In Phase II, one group was treated with Calcarea carbonica 30CH and the other group received placebo. The drugs were administered every thirty days in the Phase I and every fifteen days in the Phase II. At each step the milk samples were collected before, during and after treatment. To evaluate the effectiveness of the protocols during the experiment were analyzed 138 samples of milk at Phase I and 72 samples at Phase II, performing proof Tamis, California Mastitis Test (CMT), somatic cell count (SCC), quantification of polymorphonuclear (PMN) and mononuclear (MN) by optical microscopy, microbiological examination and measurement of milk production. Statistical analysis was performed using the software Graphpad Instat 1990-93. The homeopathic protocols tested not diminished cellularity of milk because there were no significant differences in the results of CMT and SCC during the experiment. Nor was it found no significant change in milk production. The organism isolated most frequently in the herd studied was Corynebacterium bovis. However, no significant differences were observed in the frequency of isolation of this microorganism during the treatments, indicating his permanence in the mammary glands. Furthermore, it was observed during the experiment a predominance of PMN cells compared to MN. It is suggested the study of new protocols with other homeopathic medicines, potency and frequency of administration, to find alternatives for the treatment of cows with subclinical mastitis

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Cavalheiro, Alberto Adriano [UNESP]. "Influência dos dopantes potássio e lítio na cerâmica relaxora niobato de chumbo e magnésio (PMN)." Universidade Estadual Paulista (UNESP), 2002. http://hdl.handle.net/11449/102590.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Este trabalho se focaliza na obtenção da cerâmica relaxora PMN com temperatura de máxima constante dielétrica se situando próximo à temperatura ambiente, alta constante dielétrica e valores de perda dielétrica baixos. A influência dos dopantes potássio e lítio durante a síntese dos pós e o processamento da cerâmica PMN constitui uma grande contribuição para a pesquisa deste tipo de material. Os pós de PMN foram sintetizados utilizando a rota da columbita associada ao método de coprecipitação de chumbo. O monitoramento da formação da fase columbita foi acompanhado por DRX. O refinamento de estrutura, o cálculo do tamanho médio de cristalito e a microdeformação de rede foram executadas utilizando o método de Rietveld. Além disso, as amostras foram caracterizadas por TG/DTA, BET e MEV. Diferentemente do lítio, o potássio provoca a elevação da temperatura de formação da fase MgNb2O6 (MN), mas isto não interfere na obtenção do precursor monofásico até a concentração de 2,0%mol de dopante. Para pós de MN calcinados a 900ºC por 2 horas, a presença dos dopantes atenuam a microdeformação de rede e aumentam o tamanho médio de cristalito e, conseqüentemente ocorre a formação de partículas secundárias. Os valores de tamanho médio de cristalito das amostras de PMN dopadas com lítio, calcinadas a 800ºC por 2 horas, são maiores do que para as amostras dopadas com potássio. Nesta condição, a adição de lítio também acarreta crescimento de partículas e aglomeração dos pós. Durante a sinterização, as amostras dopadas com potássio apresentaram tamanho de grão menor e com menor faixa de distribuição de tamanhos, enquanto que para o lítio houve uma menor perda de massa. A mescla de pós permitiu obter maiores valores de densidade a verde, reduzir a perda de massa e obter uma cerâmica mais densa. A adição de,...
This work aims at getting the relaxor ceramic PMN with temperature of maximum dielectric constant close to room temperature, high dielectric constant and low dielectric loss values. The influence of the potassium and lithium additives during powder synthesis and processing of the PMN ceramic constitutes a great contribution to the research of this material type. The PMN powders were synthesized by using the columbite route associated to the lead co-precipitation method. The columbite phase formation was verified by XRD. The structure refinement, calculus of mean crystallite size and lattice microstrain were performed by using the Rietveld method. Furthermore, the samples were characterized by TG/DTA, BET and SEM. Differing from lithium, potassium increases the temperature of MgNb2O6 phase formation, however it does not hinder obtaining the monophasic precursor until 2mol% of additives. For columbite powders, burned at 900ºC during 2 hours, additive presence attenuates the lattice microstrain and increases the mean crystallite size and, consequently, the secondary particle formation occurs. The values of mean size crystallite for lithium doped-PMN samples burned at 800ºC during 2 hours are bigger than potassium ones. In this condition, the lithium doping causes particles growth and powder agglomeration. In sintering, the potassium doped-PMN samples showed smaller grain size and short range of size distribution, while the lithium doped ones showed lesser weight loss. The powder mixture allowed obtaining greater green density values, decreasing weight loss and getting a denser ceramic. Potassium addition reduces Km and Tm values, while the lithium addition, increases these values if compared to PMN. The utilization of LiNbO3 seeds reduces the weight loss and helps the ceramic densification. The seeded sample showed a diffuse phase transition more...(Complete abstract, click electronic access below)

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Bruno, Juliana Catarina [UNESP]. "Influência da metodologia de síntese nas propriedades elétricas da cerâmica PMN-PT." Universidade Estadual Paulista (UNESP), 2005. http://hdl.handle.net/11449/97741.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Este trabalho propõe o estudo da influência dos métodos de síntese na obtenção da cerâmica (1-x)PMN-xPT, com x = 0,10; 0,28 e 0,35. Foram investigados muitos aspectos envolvidos em cada uma das metodologias de síntese, como quantidade de fases, reatividade superficial, homogeneidade química, densidade, perda de massa e propriedades elétricas. As metodologias de síntese abordam métodos químicos, físicos e mistos, de forma a mostrar suas aplicabilidades nas propriedades de algumas composições cerâmicas do sistema, incluindo x= 0,10, onde a propriedade é relaxora, x= 0,35 com propriedade ferroelétrica, e x= 0,28 com propriedade intermediária entre as duas. Os métodos químicos atuaram favoravelmente na obtenção de pós cerâmicos mais homogêneos e com maior reatividade superficial. Para os métodos mistos, a etapa de inserção do chumbo por via química durante a síntese dos pós de PMN-PT levou a melhores resultados do que a obtenção do pó via reação de estado sólido. Por fim, a associação da composição com a aplicação do material pôde ser estabelecida, sendo demonstrado que as cerâmicas PMN-PT 28 são melhores ferroelétricos e as cerâmicas PMN-PT 35, melhores piezoelétricos.
This work aims at studying the influence of the synthesis method in the attainment of (1-x) PMN-xPT ceramics, with x = 0.10; 0.28 and 0.35. Many aspects related to each one of the synthesis methodologies had been investigated, as phase amount, superficial reactivity, chemical homogeneity, density, weigh loss and electrical properties. The synthesis methodologies concerned chemical, physical and mixed methods, in a manner of showing its applicability in the properties of some ceramic compositions of such system, including x = 0.10, for relaxor property, x = 0.35 for ferroelectric property, and x = 0.28 with an intermediate property between the two. The chemical methods have shown to be very favorable at getting more homogeneous ceramic powders and with higher superficial reactivity. For mixed methods, the stage of lead insertion via chemical method during PMN-PT powder synthesis led to better results if compared to the solid state reaction. Finally, the association between composition and material application could be established, being demonstrated that PMN-PT 28 ceramic exhibits better ferroelectric properties, while PMN-PT 35 ceramic, piezoelectric one.

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Sakka, Aymen. "Investigation of Heat Conduction Through PMC Components Made Using Resin Transfer Moulding." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23508.

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The increasing demand for polymer matrix composites (PMCs) from the airframe industry raises the issues of productivity, cost and reproducibility of manufactured PMC components. Performance reproducibility is closely related to the manufacturing technique. Resin transfer moulding (RTM) offers the advantage of flexible manufacturing of net-shape PMC components with superior repeatability starting from ready-to-impregnate dry reinforcements. An RTM apparatus was developed for manufacturing PMC plates and demonstrator components representative of actual, PMC components and PMC moulds made and used in the airframe industry. The RTM process developed in this work involved making net-shape dry carbon fibre preforms and impregnating them an epoxy resin, targeting mould applications. Thermal repeatability of different net-shape PMC components manufactured using the RTM apparatus developed in-house was investigated. Effects of bonding an outer copper plate onto the PMC material, targeting mould applications known as integrally heated copper tooling (IHCT), were explored. Heat conduction through the PMC components was studied using simulation models validated by experimental data obtained primarily by thermography. Manufactured PMC components showed good repeatability, particularly in terms of thermal behaviour. The IHCT technique was found to be well suited for mould applications. Expected advantages of thermography were materialised. Finally, the simulation models developed were in good agreement with experimental data.

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Bruno, Juliana Catarina. "Influência da metodologia de síntese nas propriedades elétricas da cerâmica PMN-PT /." Araraquara : [s.n.], 2005. http://hdl.handle.net/11449/97741.

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Orientador: José Arana Varela
Resumo: Este trabalho propõe o estudo da influência dos métodos de síntese na obtenção da cerâmica (1-x)PMN-xPT, com x = 0,10; 0,28 e 0,35. Foram investigados muitos aspectos envolvidos em cada uma das metodologias de síntese, como quantidade de fases, reatividade superficial, homogeneidade química, densidade, perda de massa e propriedades elétricas. As metodologias de síntese abordam métodos químicos, físicos e mistos, de forma a mostrar suas aplicabilidades nas propriedades de algumas composições cerâmicas do sistema, incluindo x= 0,10, onde a propriedade é relaxora, x= 0,35 com propriedade ferroelétrica, e x= 0,28 com propriedade intermediária entre as duas. Os métodos químicos atuaram favoravelmente na obtenção de pós cerâmicos mais homogêneos e com maior reatividade superficial. Para os métodos mistos, a etapa de inserção do chumbo por via química durante a síntese dos pós de PMN-PT levou a melhores resultados do que a obtenção do pó via reação de estado sólido. Por fim, a associação da composição com a aplicação do material pôde ser estabelecida, sendo demonstrado que as cerâmicas PMN-PT 28 são melhores ferroelétricos e as cerâmicas PMN-PT 35, melhores piezoelétricos.
Abstract: This work aims at studying the influence of the synthesis method in the attainment of (1-x) PMN-xPT ceramics, with x = 0.10; 0.28 and 0.35. Many aspects related to each one of the synthesis methodologies had been investigated, as phase amount, superficial reactivity, chemical homogeneity, density, weigh loss and electrical properties. The synthesis methodologies concerned chemical, physical and mixed methods, in a manner of showing its applicability in the properties of some ceramic compositions of such system, including x = 0.10, for relaxor property, x = 0.35 for ferroelectric property, and x = 0.28 with an intermediate property between the two. The chemical methods have shown to be very favorable at getting more homogeneous ceramic powders and with higher superficial reactivity. For mixed methods, the stage of lead insertion via chemical method during PMN-PT powder synthesis led to better results if compared to the solid state reaction. Finally, the association between composition and material application could be established, being demonstrated that PMN-PT 28 ceramic exhibits better ferroelectric properties, while PMN-PT 35 ceramic, piezoelectric one.
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Ruscombe, King Benjamin Charles. "The use of(pmhc x Fab') to Retarget Cytotoxic T-cells to Non-cognate Tumour Antigen." Thesis, University of Southampton, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.509524.

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Mansour, Salah. "Development of a DC-based microsomal vaccine for delivering high doses of pMHC and costimulatory signals." Thesis, Queen Mary, University of London, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515458.

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Chaloux, Annie. "Fédéralisme, relations transfrontalières et changements climatiques en Amérique du Nord le cas de la CGNA-PMEC." Mémoire, Université de Sherbrooke, 2009. http://savoirs.usherbrooke.ca/handle/11143/2610.

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Reconnu comme un enjeu environnemental planétaire, l'acceptabilité de l'origine anthropique des changements climatiques ne fait pratiquement plus de doute au sein de la communauté internationale. L'entrée en vigueur du Protocole de Kyoto en février 2005 a eu pour résultat de pousser davantage les États à se concerter, reconnaissant la nécessité de répondre globalement à un enjeu mondialisé. Or, le cas canadien et états-unien demeure particulier à cet égard: ces derniers se sont tous deux distanciés du Protocole, alors que ceux-ci sont parmi les principaux émetteurs de gaz à effets de serre dans le monde. Toutefois, ceci n'a pas signifié pour autant l'absence de politiques à l'égard des changements climatiques sur leur territoire. Paradoxalement, cela a eu pour effet d'inciter d'autres acteurs, cette fois subétatiques, à prendre le relais et à développer nombre de politiques novatrices et divergentes de celles de Washington et Ottawa. Ainsi, ce mémoire aborde de façon ,plus particulière le développement d'une paradiplomatie environnementale au Canada et aux Etats-Unis. A travers une étude de cas particulière, soit la Conférence des gouverneurs de la Nouvelle-Angleterre et des premiers ministres de l'Est du Canada, ce mémoire s'interroge sur le rôle, les capacités d'action et les limites des États fédérés nord-américains dans le déploiement d'une diplomatie parallèle dans le domaine des changements climatiques. Nous posons également une réflexion quant à la marge de manoeuvre que les États fédérés observent dans ce type d'enjeu, et quelle est la place de l'acteur subétatique dans la lutte contre les changements climatiques.

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48

Rodrigues, Daniela Cristina Manfroi [UNESP]. "Síntese de filmes finos do sistema PMN-PT pelo método dos precursores óxidos." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/92015.

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Made available in DSpace on 2014-06-11T19:25:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-04-29Bitstream added on 2014-06-13T20:47:02Z : No. of bitstreams: 1 rodrigues_dcm_me_ilha.pdf: 1395984 bytes, checksum: 5f52de55e2329a979bca9d5a8878bbb1 (MD5)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O presente trabalho realizou uma investigação acerca da síntese de filmes finos do sistema PMN-PT utilizando o método dos precursores óxidos, associado a uma resina polimérica resultado de uma reação de condensação entre o ácido cítrico e o etileno glicol, e algumas de suas variações a fim de investigar o impacto da rota de síntese empregada sobre as fases formadas nos filmes finos. O estudo do comportamento desta resina submetida a diversas temperaturas, através do uso da técnica de espectroscopia no infravermelho, apontou que para a rota de síntese proposta os metais são incorporados à resina polimérica através de fortes ligações coordenadas com os grupos carboxilas do ácido cítrico (COO-). Também mostrou que temperaturas acima de 400°C favorecem a decomposição da cadeia orgânica e a liberação destes metais, que podem reagir com o oxigênio formando uma fase cristalina. O uso da técnica de difratometria de raios-X para a investigação das fases formadas nos filmes finos produtos de diversas modificações na síntese, apontou principalmente a dificuldade em obter os filmes livres de fases secundárias, como pirocloro, MgNb2O3,67, Mg3Nb6O11 e Pb3O4. Os principais fatores levantados para o aparecimento destas fases são: sublimação de metais como Pb e Mg levando a mudanças na estequiometria, excesso de matéria orgânica que acarreta numa pirólise descontrolada da cadeia polimérica levando à formação de aglomerados. A composição do polímero (razão ácido cítrico:etilenoglicol) pode favorecer a formação da fase desejada. Salientando ainda que os tratamentos térmicos tem importante colaboração na formação de fases, pois a diminuição do tempo durante o qual a amostra fica exposta a uma determinada temperatura pode ajudar na formação da fase desejada. O estudo desta rota de síntese forneceu filmes finos com a fase perovskita, porém...
This study conducted a research on the synthesis of PMN-PT thin films using the method of precursor oxides and some of its variants to investigate the impact of the route of synthesis employed on the phases formed in thin films. The behavior of the polymeric resin, subjected to different heat treatments, was investigated by infrared spectroscopy, showed that for the proposed route of synthesis the metals are incorporated into the polymeric resin through strong coordinated bonds with the hydroxyl group of citric acid (COO-). Temperatures above 400°C promote the pyrolysis of polymer and the release of these metals, which react with oxygen and form a crystalline phase for investigation of phases formed in thin films from changes in the synthesis, the X-ray diffraction technique was used. Mainly pointed to the difficulty to get thin films free of secondary phases, as pyrochlore, MgNb2O3,67, Mg3Nb6O11 and Pb3O4. The major factors for the appearance of these phases are: sublimation of metals such as Pb and Mg leading to losses in the composition, uncontrolled pyrolysis of a polymer chain caused by excess of the organic matter, that lead to form clusters. The composition of the polymer (ratio citric acid: ethylene glycol) may promote the perovskite phase formation. Emphasizing, the heat treatment has an important relationship on formation of phases, because the decrease of the time which the sample is exposed to heat can lead to form the desired phase, as could be observed. These route of synthesis lead to formation of perovskite phase in thin films, but the secondary phases elimination, including pirocloro, still need to be more investigated.

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49

Snukal, Katia. "Legal Absurdities and Wartime Atrocities: Lawfare, Exception, and the Nisour Square Massacre." Thesis, 2013. http://hdl.handle.net/1807/42940.

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According to the United States Department of Defense (DOD), as of 2013 there were over 12,000 DOD contractors supporting the U.S. mission in Iraq (DASD, 2013). This thesis explores the laws and legal systems that operate to keep contractors, and the companies that employ them, resistant to legal oversight. I ground my analysis in the 2007 Nisour Square massacre, exploring how every attempt to prosecute those responsible was doomed due to Blackwater’s legal position of being American-headquartered, hired by the State Department, privately owned, and operating in Iraq. I conclude that the legal indeterminacy of the US deployed security contractor normalizes violence towards Iraqi civilians while simultaneously downloading the risk and responsibility associated with the US war efforts onto the shoulders of individual contractors. Moreover, I suggest that this legal indeterminacy is of particular interest to geographers as it arises, in part, out of overlapping legal systems, jurisdictions, and authorities.

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50

Lung, Wei Jing, and 魏敬倫. "The Application of the PMAC Servo Motor Control Card." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/85236396927195038381.

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碩士
國立臺灣科技大學
機械工程研究所
84
The purpose of the present study is to refurbish an existing seven-axis probe manipulator which is a crucial part of a wind tunnel at the National Taiwan Institute of Technology. The servo controller of this probe manipulator was previously designed and built by a former graduate student and was reaching its limits, so the author replaced the original controller with a commercial product called PMAC (Programmable Multi-Axis Controller) and successfully integrated the PMAC with the servo motors, servo amplifiers, traversing and rotary mechanisms, and optical encoders that constitute the probe manipulator. PMAC is a powerful control card, and it is easy to learn and use. Detailed descriptions of the hardware and software settings, and control commands are included in this paper. The author also developed a new user interface to better meet the demand of experimental measurements. Upon a demonstration using a series of wind tunnel measurements, the author concludes that the new system is functioning satisfactorily with excellent positioning accuracy and measurement data repeatability.

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Dissertations / Theses on the topic 'PMNC'

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