2,808 research outputs found

    A Beginner’s Guide to New Testament Studies: Understanding Key Debates. [review]/Gupta, Nijay K.

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    This is a book review by André Reis

    Evaluation of bond strength, nanoleakage and physical properties of adhesive systems: a long-term study

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    Orientador: Marcelo GianniniTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de PiracicabaResumo: A efetividade dos procedimentos restauradores adesivos promovida através de diferentes protocolos de aplicação tem sido questionada com relação à durabilidade da união ao substrato dentinário. Os objetivos deste estudo foram avaliar: a resistência de união em diferentes substratos dentais; a importância dos solventes orgânicos na união produzida por adesivos que utilizam o condicionamento ácido prévio; a habilidade de diferentes adesivos em evitar a nanoinfiltração na interface resina-dentina; a sorção de água e solubilidade, a resistência à tração, o módulo de elasticidade e características ultraestruturais dos adesivos. Foram utilizados sistemas que empregam diferentes estratégias para condicionamento e infiltração no substrato dental: adesivos que utilizam condicionamento ácido prévio, adesivos de dois passos que empregam primers autocondicionantes e adesivos autocondicionantes de passo único. Os testes foram realizados após 24 h ou até o período de 12 meses de armazenagem em água e/ou óleo mineral. A resistência de união, foi avaliada através do ensaio de microtração. Para avaliação da nanoinfiltração foi utilizado AgNO3 amoniacal como agente traçador, para evidenciar espaços nanométricos e sinais de degradação nas interfaces. Os espécimes foram preparados para observação em Microsopia Eletrônica de Transmissão e/ou Varredura. Para avaliação da sorção de água e solubilidade, a variação de massa dos espécimes foi aferida. A resistência de união, a resistência máxima à tração e o módulo de elasticidade foram avaliados em máquina de ensaio universal. Os resultados mostraram que nenhum adesivo foi capaz de evitar a nanoinfiltração. A maioria dos materiais mostrou-se eficiente logo após a sua aplicação; no entanto, o comportamento da união ao longo do tempo frente a presença de água variou consideravelmente. Os adesivos autocondicionantes de passo único foram os mais susceptíveis à degradação após armazenagem em água. De acordo com as propriedades estudadas, conclui-se que: dentes bovinos são melhores substitutos para dentes humanos em testes de união; a presença de solventes orgânicos é essencial na adesão à dentina; e, a degradação da união está relacionada à hidrofilia dos materiais testadosAbstract: The effectiveness of adhesive restorative procedures promoted by different application protocols has been questioned with regard to the durability of adhesion to dentin substrate. The aims of this study were to: evaluate the bond strengths to different dental substrates; determine the importance of organic solvents in the adhesion promoted by etch-and-rinse adhesives; evaluate the ability of different adhesive systems to prevent nanoleakage in resin-dentin interfaces; and determine the water sorption and solubility, ultimate tensile strength, elastic modulus and ultrastructural characteristics of the bonding resins. Adhesive systems that use different etching and infiltration strategies were used: etch-and-rinse systems, twostep self-etching primers, and one-step self-etching adhesives. Tests were performed after 24 hours or after a storage period of up to 12 months in water and/or mineral oil. Bond strengths were analyzed by means of the microtensile bond test. Ammoniacal AgNO3 was used as a tracer for the nanoleakage test, in order to disclose nanometer-sized spaces and degradation signs within interfaces. Specimens were prepared for Transmission and/or Scanning Electron Microscopy. For water sorption and solubility analysis, the mass variation of specimens was determined. Microtensile bond strength, ultimate tensile strength and elastic modulus were analyzed in a universal testing machine. Results showed that noadhesive system was able to prevent nanoleakage. Most adhesives proved to be effective right after application; however, the behavior of bonded interfaces after long-term water-storage varied considerably. Single-step self-etching adhesives were the most susceptible to degradation after storage in water. Based on the tests performed and properties analyzed, it can be concluded that: bovine teeth are the best substitutes for human teeth in adhesion tests; organic solvents are essential in dentin adhesion; and, degradation of resin-dentin bonds is related to the hydrophilicity of the materials tested.DoutoradoDentísticaDoutor em Clínica Odontológic

    Library Free Technology Mapping

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    This paper presents an efficient method for mapping a set of Boolean equations onto a set of Static CMOS Complex Gates (SCCGs) under a constraint in the number of serial transistors. This Library Free Technology Mapping (LFTM) approach uses a virtuallibrary of SCCGs available through a layout generator, instead of using a limited set of pre characterized cells. Our goal is to use a virtuallibrary of SCCGs to perform the mapping at the transistor leveI, in order to fit the topological constraints imposed by the CMOS technology. Limitations of previously proposed techniques to perform Library Free Technology Mapping are discussed. The proposed method, based on an one-to-one association of CMOS transistors with Binary Decision Diagram ares, is not dependent on the initial ordering of Boolean equations. Experimental results comparing this technique to previously published ones indicate that it generates good-quality solutions

    Leiomyosarcoma of the Inferior Vena Cava: a case report of complete and sustained response with Trabectedin

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    Inferior vena cava leiomyosarcoma is a very rare tumor, accounting for only 0.5% of all soft tissue sarcomas. As the other leyomiosarcomas of vascular origin, they have a poor prognosis, and radical resection with surgical margins free of tumor is the only potentially curative treatment. We present a case of a 46 year-old woman with metastatic inferior vena cava leiomyosarcoma who progressed after anthracyclines and ifosfamide and achieved a complete and sustained response with trabectedin. Beyond progression, the patient started third line treatment with pazopanib. A brief review of literature is also given. This case supports the efectiveness of a recent therapeutic agent, with an impressive progression-free survival in a recurrent metastatic inferior vena cava leiomyosarcoma
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