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[pt] ANÁLISE DAS RESISTÊNCIAS DE COMPONENTES FABRICADOS POR MANUFATURA ADITIVA / [en] STRENGTH ANALYSIS OF COMPONENTS PRODUCED BY ADDITIVE MANUFACTURINGRENAN FERREIRA FRAGA WANDERLEY 05 January 2023 (has links)
[pt] A manufatura avançada, mais especificamente a manufatura aditiva, tem sido explorada cada vez mais, desde o surgimento da chamada Indústria 4.0. As técnicas de impressão 3D, incluindo a grande diversidade de tecnologias e de materiais que podem ser utilizados, permitem uma grande gama de aplicações. Com o intuito de explorar mais e aprofundar os estudos ligados a este tema, esta pesquisa investigou as propriedades mecânicas do aço inoxidável PH1, fabricado numa impressora EOS M280 através do processo de sinterização de camadas por laser. Buscou-se explorar as características do material, identificando influências da forma de fabricação e comparando as suas propriedades medidas, com as que são informadas pelo fabricante da impressora e com materiais laminados similares encontrados no mercado. Os ensaios de tração, rugosidade, dureza, impacto, M.E.V. e fadiga foram selecionados considerando a obtenção das propriedades mais relevantes do material para a indústria das peças produzidas pela tecnologia. Os resultados medidos foram comparados com os obtidos pela manufatura tradicional, para que fosse possível analisar a viabilidade e confiabilidade de substituição do método de fabricação. Estes indicam que o material impresso é resistente e pode substituir peças obtidas pela manufatura tradicional, mas deve ser utilizado com algumas considerações pois este sofre grande influência da orientação de impressão. Adicionalmente, foi desenvolvido um roteiro de fabricação digital de peças de reposição, para permitir a fabricação de peças que, juntamente com os ensaios mecânicos realizados, permite a avaliação do caminho a ser seguido dentro da manufatura aditiva para cada peça. / [en] Advanced manufacturing, more specifically additive manufacturing, has been increasingly explored since the emergence of the so-called Industry 4.0. 3D printing techniques, including the great diversity of technologies and materials that can be used, allow a wide range of applications. In order to further explore and deepen the studies related to this topic, this research investigated the mechanical properties of PH1 stainless steel, manufactured in an EOS M280 printer through the laser layer sintering process. The characteristics of the material were explored, identifying influences of the form of manufacture and comparing its measured properties with those reported by the printer manufacturer and with similar laminated materials found on the market. The tensile, roughness, hardness, impact, M.E.V. and fatigue tests were selected considering obtaining the most relevant properties of the material for the industry of the parts produced by the technology. The measured results were compared with those obtained by traditional manufacturing, so that it was possible to analyze the feasibility and reliability of replacing the manufacturing method. These indicate that the printed material is resistant and can replace parts obtained by traditional manufacturing, but it must be used with some considerations as it is greatly influenced by the printing orientation. Additionally, a script for the digital manufacturing of spare parts was developed, to allow the manufacture of parts that, together with the mechanical tests performed, allows the evaluation of the path to be followed within the additive manufacturing for each part.
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Les leucémies aiguës lymphoblastiques en 2015 : contribution des facteurs de risque cytogénétiques et moléculaires à une thérapeutique adaptée / Acute leukemia lymphoblastic in 2015 : contribution of the oncogenic and molecular risk factors to an adapted treatmentTanguy Schmidt, Aline 14 December 2015 (has links)
Les leucémies aiguës (LA) sont un groupe hétérogène d'hémopathies malignes dues à latransformation oncogénique clonale des cellules souches hématopoïétiques (CSH). On distingue les LA myéloblastiques etlymphoblastiques (LAL). Les LAL sont classées selon le type de précurseur lymphoïde atteint, leur degré de maturité et leurs anomalies cytogénétiques.Le traitement permettant d'obtenir 80 à 90 % de rémission complète (RC) comporte une chimiothérapie d'induction, une consolidation et une intensification(intensification retardée ou allogreffe de CSH selon la situation pronostique). Néanmoins la survie globale à long terme n'est que de 40 à 50 %, du fait de la survenue de rechutes et de la toxicité des traitements. Différents groupes pronostiques basés sur la cytogénétique et la biologie moléculaire se dégagent,pouvant bénéficier de thérapeutiques adaptées. Dans les LAL à chromosome philadelphie (LAL à Ph),antérieurement de mauvais pronostic, les inhibiteurs de tyrosine kinase (ITK) permettent d'obtenir 80% de RCavec cependant un taux de rechute non négligeable. Nous avons démontré qu'une intensification thérapeutique par autogreffe chez des patients avec une maladie résiduelle indétectable permettait une survie à long terme prolongée avec une toxicité moindre que celle de l'allogreffe. En montrant l'implication de l'autotaxine dans les mécanismes de résistance aux ITK dans les LAL à Ph, nous ouvrons la voie à l'utilisation potentielle de nouvelles thérapeutiques. Dans les LAL T, groupe considéré de bon pronostic, un tiers des patients rechute. Nous avons démontré que l'absence de mutation de Notch et/ou FBXW7 ou la présence de mutations de RAS ou PTEN était de mauvais pronostic identifiant un sous-groupe de LAL T dont le traitement devait être renforcé. Nos travaux ont ainsi contribué à l'identification des groupes pronostiques dans les LAL et à l'adaptation des traitements afin d'améliorer les chances de survie. / Acute leukemias are a heterogeneous groups of malignant hematological diseases due to the clonaloncogenic transformation of hematopoietic stem cells(HSTs). We distinguish acute myeloblastic leukaemiafrom acute lymphoblastic leukemia (ALL). ALLs are classified according to the type of lymphoid precursoraffected, its degree of maturity, and with associated cytogenetic abnormalities.Treatment incorporating induction therapy,consolidation, and intensification – delayedintensification or allogeneic stem cell transplantation(SCT) according to prognostic factors – enable 80 to 90% of complete remission (CR). Nevertheless, long-termoverall survival is only 40 to 50% because of relapseand treatment-related toxicity. Different prognosticgroups based on cytogenetic abnormalities andmolecular biology are emerging and patients from eachprognostic group can benefit from adapted therapies.In chromosome Philadelphia-positive ALL (Ph+ ALL) which used to be of particular bad prognosis, tyrosinekinase inhibitors (TKIs) enables 80% of CR but with ahigh-relapse risk. We demonstrated that high-dosetherapy followed by autologous SCT enables prolongedlong-term survival with less drug-related toxicity ascompared to allogeneic SCT in patients with undetectable minimal residual disease. By showing the implication of autotaxine in the resistance to TKIs inPh+ LAL, we enable the use of novel therapeutics inclinical practice.T-cell ALL is considered of poor prognosis as one thirdof patients relapse. In this group of patients we showedthat the absence of a Notch and/or a FBXW7 mutation or the presence of mutations in RAS or PTEN identified a subgroup of patients in whom the treatmentmust be intensified. Our research has contributed to the identification of prognostic groups in ALL and to theadjustment of treatment according to potential survival.
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