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Development and validation of an interpretable predictive machine learning model for successful weaning of continuous renal replacement therapy
No full textInternational audienceContinuous renal replacement therapy (CRRT) is a vital intervention for critically ill patients with severe acute kidney injury, yet no standardized criteria exist to determine the optimal time for its discontinuation. We developed and validated machine learning models to predict successful CRRT weaning, defined as survival without any form of renal replacement therapy for at least seven days after discontinuation. This retrospective multicenter study used data from two French university hospitals and the publicly available MIMIC-IV critical care database. Predictive variables were selected from routinely collected clinical and biological data to ensure real-world applicability. Models were trained on the Rouen cohort and externally validated on the Rennes and MIMIC-IV cohorts. Among the tested algorithms, the random forest model achieved the best performance, with an area under the receiver operating characteristic curve (AUROC) of 0.86 (95% CI, 0.82-0.91) in the training cohort, 0.81 (95% CI, 0.71-0.90) in the Rennes cohort, and 0.72 (95% CI, 0.65-0.78) in the MIMIC cohort. These results demonstrate the feasibility of a robust and interpretable prediction model that relies solely on routinely available data and has potential for integration into clinical workflows to support CRRT weaning decisions
3D Quantification of Subsidence During Pyrenean Retro‐Wedge Initiation: Role of Structural and Thermal Inheritance on Hyperextended Margin Inversion (Aquitaine Basin)
No full textInternational audienceWe present novel 3D subsidence data enabling vertical movements' quantification during the early formation of the Pyrenean retro-wedge. From Cenomanian to Turonian times, subsidence is relatively low (~26 ± 10 m/Myr), corresponding to a brief 10 Myr thermal re-equilibration of the European lithosphere following the hyperextended rift episode. The Coniacian-Santonian period marks a major subsidence reorganisation, with uplift or subsidence cessation on the former Early Cretaceous margin and a sudden acceleration in the necking domain (~300 ± 10 m/Myr). We interpret this episode as lithospheric buckling related to far-field deformation leading to superimposed flexural and thermal subsidence due to incomplete thermal re-equilibration. During Campanian-Maastrichtian time, subsidence decreases in the necking domain (~26 ± 10 m/Myr) and resumes on the margin (~26 ± 10 m/Myr), reflecting a homogenization of subsidence drivers across the Aquitaine Basin. This marks the progressive shift from post-rift thermal subsidence to flexural retro-foreland basin subsidence
Domino Synthesis of Functionalized Cyclic Acetals From Organic Carbonates
No full textInternational audienceWe report a method for the base-mediated transformation of ether-tethered acrylic ester-based cyclic carbonates into functionalized cyclic acetals. The protocol builds on the use of hydroxyalkyl-substituted cyclic carbonates that undergo an oxa-Michael addition reaction in the presence of alkyl propiolates thereby forging (E)-configured acrylic ether intermediates. The scope of the reaction involves the use of both five- and six-membered cyclic carbonates, and correspondingly, both five- and six-membered cyclic acetals can be prepared. The amount of reagents, the purification method, and the type of ester substrate all contribute to the efficiency of the transformation. Mechanistic control reactions point at the intermediacy of an alkoxide that induces an intramolecular Michael addition onto the acrylic double bond following alkoxide-mediated formation of both an alcohol and ester in the final product. These functional groups, among others, further enable easy diversification of acetal-based synthons
Bifunctional Molecular Switches in Fused Diarylethene–Rhodamine Systems
No full textInternational audienceA synthetic route for a novel rhodamine-based diarylethene (DAE) systems 1 and 2 is reported. The key synthetic steps involve the preparation of 6′- and 7′-bromo rhodamine precursors, their conversion into azide derivatives, and subsequent Huisgen 1,3-dipolar cycloaddition with a perfluorocyclopentene acetylene unit. The target compounds, 1 and 2, isolated in their “closed” rhodamine and “open” DAE forms, are characterized through nuclear magnetic resonance (NMR), infrared, and UV–vis absorption spectroscopies, revealing distinct electronic environments for the triazole moiety in both derivatives. Spectroscopic studies highlight their intense UV–vis absorption with minimal visible-light absorption, supported by theoretical time-dependent density-functional theory (TD-DFT) calculations. Investigation of chemo-switching behavior with trifluoroacetic acid and metal ions in dichloromethane reveals a two-step protonation process involving the triazole and rhodamine moieties, confirmed by UV–vis absorption and NMR spectroscopies. Such a process is reversible upon triethylamine addition. Selectivity tests show strong responses toward Hg2+ and Zn2+, for compound 1 displaying an additional response with Fe3+. Photoswitching experiments and TD-DFT calculations reveal distinct behaviors for compounds 1 and 2. UV irradiation of 1 results in the formation of an unexpected open-spiro rhodamine species, potentially due to photoinduced acid production. In contrast, 2 undergoes a different spectral feature arising from a degraded product with lower-lying transitions
In vitro evaluation of biocompatibility of Ti–20Zr–3Mo–3Sn β-alloy for oral implantology
No full textInternational audienceThe development of new titanium alloys for dental implants aims to eliminate potentially cytotoxic elements while achieving mechanical properties compatible with bone, particularly a low elastic modulus. This study evaluates the in vitro biocompatibility and mechanical performance of a newly developed β-type Ti-20Zr-3Mo-3Sn (Ti2033) alloy, in comparison with Ti-14Zr and Ti-6Al-4V, two reference alloys used in oral implantology. Mechanical properties were assessed by tensile testing and hardness measurements, while biocompatibility was evaluated using MTT and wound healing assays on osteoblastic cells (Saos-2). Ti2033 exhibits a significantly reduced Young's modulus (52 GPa), nearly 50% that of the reference alloys, thereby improving mechanical compatibility with bone. Although its ultimate tensile strength (825 MPa) and hardness (300 HV) are slightly lower, Ti2033 shows good ductility (elongation at rupture: 10%). No cytotoxic effects were observed, and cellular viability and migration were comparable among the three alloys. These findings suggest that Ti2033 combines mechanical performance and biocompatibility, making it a promising candidate for endosseous dental implant applications
Vers une méthode d’analyse de la sécurité des systèmes de communication sans-fil
No full textWireless communication systems have become ubiquitous to the current society. To communicate with the outside world and devices around us, many wireless technologies have been defined over the years. In the civilian world, Bluetooth, Wi-Fi, cellular networks, etc. are well-known and widely used systems. All these systems are standardized in technical specifications that may seem abstruse upon reading. The work presented in this thesis commits to studying their security. Through studies on Bluetooth, Wi-Fi, Lo- RaWAN, and 2G specifications, as well as on some implementations, this thesis assesses the security of these systems, for some desirable security properties. This advances knowledge on understanding the security issues affecting them, while also fostering reflection on the methods that can be used to analyze the security of wireless communication systems.Les systèmes de communication sans-fil sont aujourd’hui omniprésents dans notre société. Pour communiquer avec le monde et les objets qui nous entourent, de nombreuses technologies ont été définies au fil des années. Dans le monde civil, le Bluetooth, le Wi-Fi, les réseaux mobiles, etc. sont des systèmes bien connus et largement utilisés. Tous ces systèmes sont définis dans des spécifications techniques qui peuvent sembler obscures de prime abord. Les travaux présentés dans cette thèse s’attachent à en étudier la sécurité. A travers des travaux sur les spécifications Bluetooth, Wi-Fi, LoRaWAN, et 2G, ainsi que sur certaines implémentations, cette thèse évalue la sécurité de ces différents systèmes pour certaines propriétés de sécurité souhaitables. Cela permet de faire avancer la connaissance sur la compréhension des problèmes de sécurité qui les affectent, mais également d’apporter une réflexion sur les méthodes qui peuvent être utilisées pour analyser la sécurité des systèmes de communication sans-fil
Recension, Mauricette Michallet avec Christine Durif-Bruckert, Faire face à la maladie grave. L’engagement d’une femme médecin, Toulouse, Éditions Érès, 2023
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Meta-DAN: towards an efficient prediction strategy for page-level handwritten text recognition
No full textRecent advances in text recognition led to a paradigm shift for page-level recognition, from multi-step segmentation-based approaches to end-to-end attention-based ones. However, the naïve character-level autoregressive decoding process results in long prediction times: it requires several seconds to process a single page image on a modern GPU. We propose the Meta Document Attention Network (Meta-DAN) as a novel decoding strategy to reduce the prediction time while enabling a better context modeling. It relies on two main components: windowed queries, to process several transformer queries altogether, enlarging the context modeling with near future; and multi-token predictions, whose goal is to predict several tokens per query instead of only the next one. We evaluate the proposed approach on 10 full-page handwritten datasets and demonstrate state-of-the-art results on average in terms of character error rate. Source code and weights of trained models are available at https://github.com/FactoDeepLearning/meta_dan
Experimental Demonstration of Demand-Driven PON Configuration for Fixed-Mobile Convergence
No full textInternational audienceHere, we address fixed-mobile convergence using an SDN-enabled PON with dynamic T-CONT configuration. Sub-millisecond PON latency is demonstrated for mobile traffic while reducing bandwidth usage by up to 80% during off-peak periods. We also compare different network configuration approaches with a Random Forest prediction model
Systemic sclerosis: pathogenic mechanisms and their implications for treatment
No full textInternational audienceSystemic sclerosis (SSc) is a rare systemic autoimmune disease characterized by a triad of pathogenic mechanisms, including: a) microvascular hyperreactivity secondary to endothelial dysfunction, b) dysregulated immune activation of both innate and adaptive immunity, with the production of autoantibodies targeting nuclear antigens (e.g., anticentromere antibodies, anti-RNA polymerase III antibodies, and anti-topoisomerase I antibodies), and c) fibrosis of the skin and internal organs, such as the lungs, due to excessive extracellular matrix deposits produced by dysregulated myofibroblasts. Skin involvement plays a crucial role in the detrimental impact of SSc on quality of life. Skin fibrosis in SSc is characterized by the progressive accumulation of extracellular matrix components, including collagen, in the dermis, and is associated with adipocyte atrophy in the hypodermis. Visceral manifestations include fibrotic interstitial lung disease (ILD), myocardial involvement, pulmonary arterial hypertension, gastrointestinal manifestations, and scleroderma renal crisis. These manifestations are key determinants of prognosis and significant contributors to mortality in SSc. This review will explore the clinical features of SSc, the existing subtypes based on different classification approaches (such as skin-driven classifications, autoantibodies, or molecular subsets), epidemiology, identified etiologies, pathogenesis, current standards of care, and a selection of potential therapeutic perspectives. This review will emphasize SSc-related skin manifestations, including their pathogenesis and treatment, while also discussing other organ manifestations