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Definitional Proof Irrelevance Made Accessible
No full textA universe of propositions equipped with definitional proof irrelevance constitutes a convenient medium to express properties and proofs in type-theoretic proof assistants such as Lean, Rocq, and Agda. However, allowing accessibility predicates---used to establish semantic termination arguments---to inhabit such a universe yields undecidable typechecking, hampering the predictability and foundational bases of a proof assistant. To effectively reconcile definitional proof irrelevance and accessibility predicates with both theoretical foundations and practicality in mind, we describe a type theory that extends the Calculus of Inductive Constructions featuring observational equality in a universe of strict propositions, and two variants for handling the elimination principle of accessibility predicates: one variant safeguards decidability by sticking to propositional unfolding, and the other variant favors flexibility with definitional unfolding, at the expense of a potentially diverging typechecking procedure. Crucially, the metatheory of this dual approach establishes that any proof term constructed in the definitional variant of the theory can be soundly embedded into the propositional variant, while preserving the decidability of the latter. Moreover, we prove the two variants to be consistent and to satisfy forms of canonicity, ensuring that programs can indeed be properly evaluated. We present an implementation in Rocq and compare it with existing approaches. Overall, this work introduces an effective technique that informs the design of proof assistants with strict propositions, enabling local computation with accessibility predicates without compromising the ambient type theory
: contributions du droit, du français, de la géographie, de l'histoire, des arts, des SVT et des mathématiques aux compétences citoyennes
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A posteriori-driven adaptive strategy for solving inverse Cauchy problems in diffusion-reaction models
No full textInternational audienceThis work addresses the inverse Cauchy problem for the modified Helmholtz equation using an alternating iterative approach. The central contribution lies in the design of novel local error indicators based on a posteriori analysis, which simultaneously assess the accuracy of the spatial discretization and the convergence behavior of the iterative algorithm. Unlike standard methods, our strategy leverages a comparative assessment of these indicators to drive an adaptive mesh refinement process. This adaptive framework ensures a more balanced distribution of computational resources, significantly reducing the numerical cost while maintaining high solution accuracy. The proposed methodology is validated through a series of synthetic and application-driven numerical experiments, demonstrating both its effectiveness and robustness in reconstructing inaccessible boundary data
SPH modelling of water flow inside a fixed and undeformable porous medium using a Riemann based formulation
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Severity of complications is associated with impaired health‐related quality of life in people with type 1 diabetes
No full textInternational audienceAims Health‐related quality of life (HRQoL) assessment is increasingly integrated into type 1 diabetes (T1D) monitoring to promote a holistic approach. To investigate HRQoL in adults with T1D and to assess the impact of the severity of complications on HRQoL. Materials and Methods This is a cross‐sectional analysis of baseline characteristics of adults living with T1D included in Société Francophone du Diabète – Cohorte Diabète de Type 1 (SFDT1), a French longitudinal cohort study. HRQoL was assessed using generic (EuroQol 5‐Dimensions 5‐Level questionnaire [EQ‐5D‐5L]) and diabetes‐specific (Audit of Diabetes‐Dependent Quality of Life) instruments. The severity of diabetes complications was measured using an adapted Diabetes Complication Score Index (DCSI) ranging from 0 to 14. We used multiple imputations to deal with missing data. Results We included 1892 adults, 48% women, with a median (interquartile range [IQR]) age of 38 (28; 51) years. The mean overall EQ‐5D‐5L HRQoL score was 71.1 ± 17.7 (maximum 100), with the following number of participants negatively impacted for each domain: 271 (14%) for mobility, 94 (5%) for self‐care, 378 (19%) for usual activities, 853 (45%) for pain/discomfort and 983 (52%) for anxiety/depression. The median (IQR) DCSI was 1 (0; 2). In multivariable models, a one‐step increase in DCSI was associated with a 1.5% decrease in overall EQ‐5D‐5L HRQoL. DCSI was also inversely associated with all domains of the generic scale except anxiety/depression and 17 domains of the diabetes‐specific scale. Conclusions We observed an inverse association between the severity of complications and overall HRQoL and most of its dimensions. Our results highlight the need to reinforce the prevention of complications to improve the overall well‐being of people with T1D
Proceedings of the AI WILD West 2026
No full textInternational audienceArtificial Intelligence Workshop on Inverse problem, Learning, imaging & Data science in the West (AI WILD West) aims to bring together researchers working at the interface of inverse problems, artificial intelligence, and applied mathematics. The workshop focuses on methodological advances and their applications in translational research, imaging and data science. By fostering interactions between theory and practice, the workshop encourages cross-disciplinary exchanges between mathematics, machine learning, and application-driven research communities
Sortir de la grotte pour mieux y rentrer : à la recherche d’invariants
No full textInternational audienceBernard Lahire’s thinking is extremely motivating because it allows us to connect the social with the living, to identify “lines of force” and “laws” that permit the creation of a scientific language that transcends mere descriptions and protects us from general discourses too disconnected from reality. Is it possible to make a considerable leap forward in time and apply these ideas to periods without written records, about which we know practically nothing? This is a new path to explore, and we present here the first, undoubtedly still clumsy, strokes of the pruning knife.La pensée de Bernard Lahire est extrêmement motivante, car elle permet d’articuler le social avec le vivant, d’identifier des « lignes de force » et des « lois » qui autorisent la création d’un langage scientifique dépassant les simples descriptions et qui nous préserve des discours généraux trop déconnectés du réel. Est-il possible de faire un saut considérable dans le temps et de les appliquer à des époques sans trace écrite, dont nous ne connaissons pratiquement rien ? Voici un nouveau chemin à défricher, dont nous présentons ici les premiers coups de serpette, encore maladroits sans doute
The Greeks among the natives: Culture, ritual, and craftmanship in non-colonial spaces of the Southern Italy Iron Age
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Evolution of the sentinel lymph node procedure following the approval of adjuvant anti-PD-1 therapy for stage IIB and IIC melanoma: A multicenter study from RICMEL database
No full textInternational audienceIntroduction: Programmed cell death protein (PD)-1 inhibitors can be initiated for stage IIB-IIC melanomas after complete surgical resection following marketing authorization, to reduce the risk of recurrence later in the disease course. A year after this significant change to our therapeutic arsenal in France, we reflect on how this earlier initiation of immunotherapy may influence the practice of the sentinel lymph node biopsy (SLNB) and the overall staging of melanomas, particularly in an era where SLNB is increasingly considered outdated. The aim of this study is to compare the incidence of de novo IIB-IIC-III melanoma between 2021/2022 and 2023, and to examine the relationship between the stage III incidence and the number of SLN procedures to determine whether this therapeutic change has impacted melanoma staging practices.Materials and methods: We conducted a retrospective cohort study of 1158 de novo melanomas stage IIB-IIC and III diagnosed between 2021 and 2023. Data were extracted from the RICMEL database, a French, multicenter melanoma registry.Results: The incidence of SLNB dropped significantly following the marketing authorization of adjuvant anti-PD-1 therapy, decreasing from 59.1 % in 2021/2022 to 38.1 % in 2023 (p < 0.0001). This decline was accompanied by a significant shift in the staging of IIB-IIC-III melanomas.Conclusion: Although prognostic scores or new marketing authorization could suggest performing fewer SLNBs, the reduced use of SLNB due to earlier access to immunotherapy may result in inaccurate melanoma staging, potentially affecting prognosis and treatment decisions