170 research outputs found
A dual thromboxane inhibitor and thromboxane receptor antagonist prevents pig myocardial infarction induced by coronary thrombosis
peer reviewe
Anatomie pathologique
SYL-8729 = 1re partie1re partie :Anatomie pathologique généraleDENT3, DENT033info:eu-repo/semantics/published
Anatomie pathologique :Anatomie pathologique spéciale
SYL-8706 = 2e partie2e partie :Anatomie pathologique spécialeDENT3, DENT033info:eu-repo/semantics/published
Contribution de variables morphologiques quantitatives au diagnostic des lésions bénignes et malignes de la prostate: mise au point d'un système expert lié à la microscopie assistée par ordinateur et à l'intelligence artificielle
Doctorat en sciences médicalesinfo:eu-repo/semantics/nonPublishe
Travaux pratiques d'anatomie pathologique de la bouche et des glandes salivaires
DENT4 - ANAT033info:eu-repo/semantics/published
Anatomie pathologique de la bouche, des maxillaires et des glandes salivaires
1ère édition 2000-01/1DENT4, ANAT033info:eu-repo/semantics/published
Contribution de variables morphologiques quantitatives au diagnostic des lésions bénignes et malignes de la prostate: mise au point d'un système expert lié à la microscopie assistée par ordinateur et à l'intelligence artificielle
Doctorat en sciences médicalesinfo:eu-repo/semantics/nonPublishe
Anatomie pathologique
SYL-10517 = 1re partie. Anatomie pathologique générale ;SYL-10520 = 2e partie - Anatomie pathologique spécialeDENT3 - MORF-G-301info:eu-repo/semantics/published
On the interactions between strain-induced phase transformations and mechanical properties in Mn-Si-Al steels and Ni-Cr austenitic stainless steels
L'augmentation constante de la circulation automobile a travers le monde fait des effluents gazeux un des problèmes majeurs de toutes les sociétés modernes. Tant d'un point de vue économique et écologique, chacun s'accorde sur le fait que la consommation de carburants fossiles utilisés dans le transport doit baisser, principalement en réduisant le poids des véhicules. Le développement de matériaux à hautes performances et à bas prix est donc indispensable.
Pour atteindre cet objectif, cette étude visait à élucider les interactions entre la déformation et les transformations de phase dans les aciers a hautes performances qui pourraient remplir les conditions de réduction de poids. En effet, une large gamme de travaux a montrer que les transformations de phase induites mécaniquement (effet TRIP) de l'austénite peuvent être à l'origine d'une amélioration des propriétés mécaniques dans de nombreuses nuances d'acier.
Les transformations de phase induites par la déformation dépendent de deux paramètres : la stabilité relative et l'énergie de fautes d'empilement de l'austénite, qui sont affectes par différents facteurs. Les interactions entre les transformations de phase et les propriétés mécaniques de différentes nuances Cr-Ni et Mn-Si-Al furent examinées sous plusieurs conditions de taille de grain, de température et d'état de chargement. Des relations particulières furent établies entre les phénomènes qui se produisent a l'échelle des grains individuels et a l'échelle macroscopique. Les mécanismes cristallographiques des transformations de phase successives (austénite - martensite e - martensite a') ont été mis en évidence.
Finalement, différentes techniques de raffinage de la taille de grain furent utilisées pour produire des aciers inoxydables comportant des tailles de grain variées, et l'efficacité de ces techniques a été comparée. Pour cela, les cinétiques de retransformation, recrystallisation et croissance des grains ont été étudiées. La réduction de taille des grains par cycles de transformations de phase fut établie comme plus efficace de la méthode classique par déformation - recristallisation.The continuously increasing use of automobiles all over the world, is making of gas effluents one of the major concerns for all modern societies. From economical and ecological points of view, everyone agrees on the fact that the consumption of fossil fuels for transport must decrease, particularly by vehicle weight reduction. Development of high performance materials at low cost is therefore needed.
In order to achieve this requirement, the present work aimed at investigating the interactions between straining and phase transformations in high performance steels that could meet the weight saving requirements. Indeed, a wide range of studies has shown that mechanically-induced phase transformations (TRIP effect) of the austenite may bring about improved mechanical properties in different steel grades.
Strain-induced phase transformations depend on two parameters : the relative stability and the stacking fault energy of the austenite, which are affected by different factors. The interactions between the phase transformations and the mechanical properties of different Ni-Cr and Mn-Si-Al grades were examined under various conditions of grain size, temperature or stress state. Particular relationships were clearly established between the phenomena taking place at the scale of the individual grains and at the macroscopic scale. The crystallographic mechanisms of the successive strain-induced phase transformations (austenite - e-martensite - a'-martensite) has been clarified.
Finally, different techniques of grain refinement were used to process stainless steels with various grain sizes, assessing the efficiency of these techniques. Therefore, the kinetics of retransformation, recrystallisation and grain growth were studied. Grain refinement by cycles of phase transformations was found more effective than the classical deformation - recrystallisation method.(FSA 3)--UCL, 200
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Specificity of Enzyme Immunoassay for Serologic Coccidioidomycosis Diagnosis Compared to Immunodiffusion
A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine.BACKGROUND: Serologic testing for coccidioidomycosis challenges clinicians due to conflicting small studies regarding the sensitivity and specificity of newer enzyme immunoassay (EIA) tests and the lack of a true gold standard diagnostic test for comparison. METHODS: We analyzed all Lab Corp coccidioidomycosis serological test results from February 2008 through February 2009 and calculated the sensitivity, specificity, and positive/negative predictive values of EIA immunoglobulin (Ig)M and IgG. Immunodiffusion IgM and IgG (ID), complement fixation titers (CF), and tissue/culture diagnosis were used as tests for comparison. The comparison test (CT) was considered positive if any comparison test was positive the day of EIA collection or if tissue/culture diagnosis occurred during the time period. Cases required EIA IgM and IgG and ≥ 2 comparison tests performed the same day for inclusion. Medical records associated with positive EIA and negative comparison test results were reviewed for coccidioidomycosis symptoms, physician diagnosis, and subsequent positive comparison test results. Sensitivity, specificity, and predictive values were calculated, including those with subsequent positive comparison test results. RESULTS: A total of 1445 laboratory test sets were identified. EIA sensitivity and specificity were 83.8% and 92.6%, respectively. Positive and negative predictive values were 61.5% and 97.6%, respectively. Of 94 “false positive” EIA results, 92 (97.9%) were associated with documented coccidioidomycosis symptoms and 81% with coccidioidomycosis physician diagnosis. CONCLUSION: Based on the largest study of sensitivity and specificity calculated from laboratory surveillance data, EIA sensitivity and specificity for coccidioidomycosis diagnosis are lower than previously reported using only coccidioidomycosis laboratory tests as a comparison. However, association of “false positive” EIA results with coccidioidomycosis symptoms and physician diagnosis suggests that ID and CF laboratory tests alone are not a sufficient confirmation test for diagnosis.This item is part of the College of Medicine - Phoenix Scholarly Projects 2011 collection. For more information, contact the Phoenix Biomedical Campus Library at [email protected]
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