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Factors associated with remission at 5-year follow-up in recent-onset axial spondyloarthritis: results from the DESIR cohort
No full textInternational audienceAbstract Objective The factors contributing to long-term remission in axial SpA (axSpA) are unclear. We aimed to characterize individuals with axSpA at the 5-year follow-up to identify baseline factors associated with remission. Methods We included all patients from the DESIR cohort (with recent-onset axSpA) with an available Ankylosing Spondylitis Disease Activity Score–CRP (ASDAS-CRP) at 5-year follow-up. Patients in remission (ASDAS-CRP < 1.3) were compared with those with active disease by demographic, clinical, biological and imaging characteristics. A logistic model stratified on TNF inhibitor (TNFi) exposure was used. Results Overall, 111/449 patients (25%) were in remission after 5 years. Among those never exposed to TNFi, 31% (77/247) were in remission compared with 17% (34/202) of those exposed to TNFi. Patients in remission after 5 years were more likely to be male, HLA-B27+, have a lower BMI, and a higher education level. Baseline factors associated with 5-year remission in patients never exposed to TNFi included lower BASDAI [adjusted odds ratio (ORa) 0.9, 95% CI: 0.8, 0.9) and history of peripheral arthritis (ORa 2.1, 95% CI: 1.2, 5.3). In those exposed to TNFi, remission was associated with higher education level (ORa 2.9, 95% CI: 1.6, 5.1), lower enthesitis index (ORa 0.8, 95% CI: 0.7, 0.9), lower BASDAI (ORa 0.9, 95% CI: 0.9, 0.9) and lower BMI (ORa 0.8, 95% CI: 0.7, 0.9). Conclusion This study highlights the difficulty in achieving 5-year remission in those with recent-onset axSpA, especially for the more active cases, despite the use of TNFi. Socio-economic factors and BMI are implicated in the outcome at 5 years
Modélisation et simulation des effets mécaniques d’expansions internes dues à la corrosion d’inclusions métalliques dans des matrices cimentaires
No full textThis thesis deals with the disposal of low-level, long-lived waste from ORANO, composed mainly of graphite, magnesium and uranium residues. The waste is immobilized in a metal container by a matrix based on Alcali-Activated slag cement. The presence of free water in the cement pores can accelerate the corrosion reactions of the metallic particles, such as magnesium, and uranium. The expansion due to the formation of corrosion products might cause microcracks in the cement matrix. The cemented waste package is characterized by a strong material heterogeneity at different scales, and its mechanical behavior is impacted by the existence of potential cracks at the microscopic scale. The EF² method has been introduced as a general multiscale method to solve problems of nonlinear heterogeneous structures. At the macroscopic scale, each integration point of the finite element mesh is associated with a representative volume element (RVE). The major drawback of this method is the prohibitive computational cost, since it is required, for each computational step, to solve a nonlinear problem over RVE at each integration point at the macroscopic scale. A new machine-learning based multiscale method, called k-means FE², is developed to solve general nonlinear multiscale problems with internal variables and loading history dependent behavior. The macroscale problem is reduced by constructing clusters of Gauss points in a structure that are estimated to be in the same mechanical state. A machine-learning k-means clustering algorithm is used to select Gauss points based on their strain state. Then, for all Gauss points in a cluster, a single nonlinear microscopic problem is solved, and its answer is transferred to all integration points in the cluster in terms of mechanical properties. The convergence of the k-means FE² method must be verified with respect to the number of clusters in the macroscopic structure, and the EF² reference solution. The k-means FE² method is applied on a cemented waste problem considering microstructures with several volume fractions of graphiteCette thèse s'inscrit dans le cadre du conditionnement des déchets de faible activité et à vie longue d'ORANO, constitués majoritairement de graphite, de magnésium et de résidus d'uranium. Les déchets sont immobilisés dans un conteneur métallique par une matrice à base de ciment de laitier Alcali-Activé. L'eau dans les pores de ciment peut accélérer les réactions de corrosion des phases métalliques, telles que le magnésium, et l'uranium. L'expansion due à la formation de produits de corrosion peut entrainer des microfissures dans la matrice cimentaire. Le colis de déchets cimentés est caractérisé par une forte hétérogénéité matérielle à différentes échelles, et son comportement mécanique est impacté par l'existence d'éventuelles fissures à l'échelle microscopique. La méthode FE² a été introduite comme une méthode générale multi-échelle pour résoudre des problèmes de structures hétérogènes non linéaires. À l’échelle macroscopique, chaque point d'intégration du maillage éléments finis est associé à un volume élémentaire représentatif (VER). L'inconvénient majeur de cette méthode est le coût de calcul prohibitif, car il est requis, pour chaque étape de calcul, de résoudre un problème non linéaire dans un VER en chaque point d'intégration à l'échelle macroscopique. Une nouvelle méthode multi-échelle basée sur le machine-learning, appelée k-means FE², est développée ici pour résoudre des problèmes multi-échelle non linéaires généraux avec des variables internes et des comportements dépendant de l'histoire de chargement. Le problème à l’échelle macroscopique est réduit en construisant des clusters de points de Gauss dans une structure qui sont estimés être dans le même état mécanique. Un algorithme de machine-learning k-means clustering est utilisé pour sélectionner les points de Gauss en fonction de leur état de déformation. Ensuite, pour tous les points de Gauss d'un cluster, un seul problème microscopique non linéaire est résolu, et sa réponse est transférée à tous les points d'intégration du cluster en termes de propriétés mécaniques. La convergence de la méthode k-means FE² doit être vérifiée par rapport le nombre de clusters dans la structure macroscopique, et la solution de référence EF². La méthode k-means FE² est appliquée sur un problème de déchets cimentés en considérant des microstructures avec plusieurs fractions volumiques de graphit
Prevalence of anti-TNF contraindications in Crohn’s disease: A cross-sectional survey from the GETAID
No full textInternational audienceBACKGROUND: The exact rate of contraindications to anti-TNF therapy and physician perspectives on treatment choices facing to anti-TNF contraindication, are poorly reported. METHODS: A two-week cross-sectional study was conducted in 31 centres. Physicians completed a questionnaire for a total of 1,314 consecutive outpatients with Crohn’s disease, assessing each patient’s potential contraindications to anti-TNF therapy, the choice of alternative therapy to anti-TNFs, and their preference in an unrestricted reimbursement setting. RESULTS: Among the 1,293 responses to the first item, 148 (11.5%) reported 32 absolute contraindications (2.5%) and 116 relative contraindications (9.0%) to anti-TNF therapy. When asked about their preference of alternative therapies in those cases with contraindications to anti-TNF, physicians chose ustekinumab and vedolizumab, 75.6% and 23.9%, respectively. In multivariable analysis, the choice of vedolizumab was the preferred choice for patients aged > 60 years with the L2 phenotype and the absence of perianal lesions. In a hypothetical setting of unrestricted reimbursement, anti-TNFs remained physicians’ preferred first-line biological therapy choice for 78.2%. CONCLUSION: Anti-TNF contraindications occurred in up to 11.5% of patients with Crohn’s disease. Physicians’ choices for alternative therapy to anti-TNF relied on ustekinumab in 75.6% and vedolizumab in 23.9% of these cases. This choice was driven mainly by phenotypical criteria and age
Functional Nanoporous Materials From Boronate-Containing Stimuli-Responsive Diblock Copolymers
No full textInternational audienceFunctional nanoporous polymeric materials have been prepared from novel polystyrene-blockpoly(ethylene oxide) (PS-b-PEO) diblock copolymer precursors containing a reversible boronate ester junction between both blocks. To this purpose, homopolymers presenting either a boronic acid or a (nitro)catechol end functionality were synthesized. The coupling of each homopolymer presenting complementary chemical functions was successfully achieved under mild conditions and allowed for the generation of the corresponding boronate ester-containing diblock copolymers. Upon orientation of these precursors on silicon wafers via solvent vapor annealing, the resulting films were submitted to PEO etching through selective cleavage of the boronate ester junction under mild acidic conditions. SEM micrographs of the as-obtained thin films revealed the generation of 12-nm-diameter oriented cylindrical nanopores perpendicular to the silicon support surface
Improved Processability and Antioxidant Behavior of Poly(3-hydroxybutyrate) in Presence of Ferulic Acid-Based Additives
No full textInternational audiencePoly(3-hydroxybutyrate), PHB, has gathered a lot of attention for its promising properties—in particular its biobased nature and high biodegradability. Although PHB is prime candidate for the packaging industry, the applications are still limited by a narrow processing window and thermal degradation during melt processing. In this work, three novel additives based on ferulic acid esterified with butanediol, pentanediol, and glycerol (BDF, PDF, and GTF, respectively) were used as plasticizers and antioxidative additives to improve mechanical properties of PHB. Elongation at break up to 270% was obtained in presence of BDF and the processing window was improved nearly 10-fold. The Pawley method was used to identify the monoclinic space group P2 of the BDF. The estimated crystallite size (71 nm) agrees with a crystalline additive. With PHB70BDF30 blends, even higher elongations at break were obtained though dwindled with time. However, these properties could be recovered after thermal treatment. The high thermal stability of this additive leads to an increase in the fire retardancy property of the material, and the phenolic structure induced antioxidant properties to the samples as demonstrated by radical scavenging tests, further highlighting the possibilities of the PHB/additive blends for packaging applications
Du gaspillage au réemploi : processus de (re)création de valeur des objets dans les pratiques de don et de vente
No full textInternational audienceThis research aims to understand how individuals transform the perceived value of their unused objects for re-use through donation and sale, by considering these practices as processes of dispossession, i.e. processes of physical and/or psychological separation. Through a longitudinal qualitative study conducted with 28 informants, we show that individuals, when they give or sell, transform the status of the object through four stages: spatial distancing, regaining of control, valorization and effective separation. At each of these stages, the relation object - subject evolves: the object is respectively comforting or distressing private possession, cumbersome private possession, object to be valued, and then social, civic or commercial object. Thus, far from being influenced by their possessions, individuals are actors who make the meaning given to objects evolve through actions and well-defined spatio-temporal trajectories.Cette recherche vise à comprendre comment les individus transforment la valeur perçue de leurs objets inutilisés pour les réemployer par le don et la vente, en considérant ces pratiques comme des processus de dépossession, c'est-à-dire des processus de séparation physique et/ou psychologique. Par le biais d'une étude qualitative longitudinale menée auprès de 28 informants, nous montrons que les individus, quand ils donnent ou vendent, transforment l'objet au travers de quatre étapes que sont la mise à distance spatiale, la reprise de contrôle sur l'objet, sa valorisation et sa séparation effective. Dans chacune de ces étapes, le rapport objet-sujet évolue : l'objet est respectivement possession privée réconfortante ou angoissante, possession privée encombrante, objet à valoriser, puis objet social, civique ou marchand. Ainsi, loin d'être seulement influencés par l'objet, les individus sont des acteurs qui font évoluer la valeur donnée à leurs possessions au travers d'actions et de trajectoires spatio-temporelles bien définies
Quantification of Microplastics by Pyr-GC-MS in Sediments: Challenges and Implications
No full textInternational audienc
De la conception à l’exploitation ? : L’intégration des préoccupations d’exploitation des systèmes énergétiques dans la conception des projets urbains
No full textFrom design to exploitation?The integration of exploitation concerns of energy systems into the design of of urban projectsFacing negative feedback during the exploitation of sustainable urban projects, actors are increasingly integrating the operational concerns of energy systems into the design process. The research objective is to question the effects of this operational issues integration in the urban design process.Based on a case analysis, we show that the integration of operational concerns leads to changes in technical choices, energy objectives and the social organisation of design. There is a bifurcation of technical choices, following/after double-loop learning by the actors, where the objectives have to be revised during the design process in order to move forward. Indeed, reasoning in terms of exploitation leads to different design choices prioritising the quality of use and of provided services. In terms of design organisation, the integration of operational concerns does not question the hierarchical and linear rhythm of the organisation of the actors' activities. However, it does facilitate the affirmation of new actors such as the operators of energy and multi-service systems. More broadly, the research shows that the feedback from more than fifteen years of experience in the operation of sustainable districts contributes to an interprofessional learning process, which sedimentation produces new technical or design references and contributes to the renewal of professional cultures. In this way, the design activity is transformed. In particular, the analysis emphasises the importance of technical objects for consolidating the actors' learning, objects around which lessons and feedback crystallised.Face aux retours d’expériences négatifs pendant l’exploitation des projets urbains durables, les acteurs se mettent à intégrer de plus en plus les préoccupations d’exploitation des systèmes énergétiques dans la conception. L’objectif de cette recherche est d’interroger les effets de cette intégration des enjeux d’exploitation sur le processus de conception urbaine. À partir d’une analyse de cas, nous montrons que l’intégration des préoccupations d’exploitation engendre des évolutions des choix techniques, des objectifs énergétiques et des paramètres de l’organisation sociale de la conception. On assiste à une bifurcation des choix techniques, suite à des apprentissages en double boucle des acteurs, où il s’agit de revoir les objectifs en cours de conception pour pourvoir avancer. En effet, raisonner en termes d’exploitation amène à réaliser des choix de conception différents priorisant la qualité d’usage et de services rendus. En matière d’organisation de la conception, l’intégration des préoccupations d’exploitation ne requestionne pas le rythme hiérarchique et linéaire d’organisation des activités des acteurs. Toutefois, cela facilite l’affirmation de nouveaux acteurs comme les exploitants des systèmes énergétiques et multi-services. Plus largement, la recherche montre que les retours d’expériences, de plus d’une quinzaine d’années autour de l’exploitation des quartiers durables, contribuent à un processus d’apprentissage interprofessionnel, dont les sédimentations produisent de nouvelles références techniques ou de projets, et participent au renouvellement des cultures professionnelles. De cette manière, l’activité de conception se transforme. L’analyse met notamment l’accent sur l’importance des objets techniques dans la consolidation des apprentissages des acteurs, des objets autour desquels se cristallisent les enseignements et les retours d’expériences
Long-term survival benefit from dual kidney transplantation using kidneys from donors with very extended criteria-a French cohort between 2002 and 2014
No full textInternational audienceBACKGROUND: This national multicentre retrospective cohort study aimed to assess the long-term outcomes of dual kidney transplantation (DKT) and compare them with those obtained from single kidney transplantation (SKT). METHODS: Our first analysis concerned all first transplants performed between May 2002 and December 2014, from marginal donors, defined as brain death donors older than 65 years, with an estimated glomerular filtration rate (eGFR) lower than 90 mL/min/1.73 m2. The second analysis was restricted to transplants adequately allocated according to the French DKT program based on donor eGFR: DKT for eGFR between 30 and 60, SKT for eGFR between 60 and 90 mL/min/1.73 m2. Recipients younger than 65 years or with a panel-reactive antibody percentage ≥25% were excluded. RESULTS: The first analysis included 461 DKT and 1131 SKT. DKT donors were significantly older (77.6 versus 74 years), had a more frequent history of hypertension and a lower eGFR (55.1 versus 63.6 mL/min/1.73 m2). While primary nonfunction and delayed graft function did not differ between SKT and DKT, 1-year eGFR was lower in SKT recipients (39 versus 49 mL/min/1.73 m2, P < 0.001). Graft survival was significantly better in DKT, even after adjustment for recipient and donor risk factors. Nevertheless, patient survival did not differ between these groups. The second analysis included 293 DKT and 687 SKT adequately allocated with donor eGFR and displayed similar results but with a smaller benefit in terms of graft survival. CONCLUSIONS: In a context of organ shortage, DKT is a good option for optimizing the use of kidneys from very expanded criteria donors