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Early-Reverberation Imaging Functions for Bounded Elastic Domains
No full textInternational audienceFor the ultrasonic inspection of bounded elastic structures, finite-duration imaging functions are derived in the Fourier-Laplace domain.The signals involved are exponentially windowed, so that early reflections are taken into account more strongly than later ones in the imaging methodology.Applying classical approaches to the general case of anisotropic elasticity, we express the Fréchet derivatives of the relevant data-misfit functional with respect to arbitrary perturbations of the mass density and stiffnesses in terms of forward and adjoint solutions.Their definitions incorporate the exponentially decaying weighting. The proposed finite-duration imaging functions are then defined on that basis.As some areas of the structure are less insonified than others, it is necessary to define normalized imaging functions to compensate for these variations.Our approach in particular aims to overcome the difficulty of dealing with bounded domains containing defects not located in direct line of sight from the transducers and measured signals of long duration.For this initiation work, we demonstate the potential of the proposed method on a two-dimensional test case featuring the imaging of mass and elastic stiffness variations in a region of a bounded isotropic medium that is not directly visible from the transducers
Investigating the Effects of Augmented Reality on Message Credibility When Visualizing Environmental Impacts
No full textInternational audienceAugmented reality (AR) has increasingly been used to communicate environmental impacts, offering greater engagement than conventional displays. However, its effect on message credibility—how much people believe in the content of the communication—remains unclear. In a preregistered study, we compared the perceived credibility of environmental information presented via visualizations on an AR headset or a desktop display. We created display-specific visual encodings (3D concrete for AR, 2D bar charts for desktop) and added two control conditions to cross display and encoding. We found no difference in message credibility between AR and desktop, though concrete AR was rated most engaging. Supplementary material is available at https://osf.io/n4p5c/
CHEBYSHEV'S BIAS WITHOUT LINEAR INDEPENDENCE
No full textWe confirm Chebyshev's observation that primes are strikingly more abundant in non-square residue classes modulo a fixed integer under the Generalized Riemann Hypothesis (GRH) by proving a (natural) density statement for prime counting functions in residue classes where each prime is weighted by its inverse square root. In contrast to the majority of the existing literature on the subject, we do not need to restrict to logarithmic densities to measure Chebyshev's bias, and we do not rely on any hypothesis on the zeros of -functions that is stronger than GRH
Inapplication de l'infraction de l'article L. 610-1 du code de l'urbanisme en l'absence d'entrée en vigueur du PLU
No full textInternational audienceCour de cassation, crim., 12 novembre 2025, no 25-81.179, inédi
New Trends in the Stability of Sinkhorn Semigroups
No full textEntropic optimal transport problems play an increasingly important role in machine learning and generative modelling. In contrast with optimal transport maps which often have limited applicability in high dimensions, Schrodinger bridges can be solved using the celebrated Sinkhorn's algorithm, a.k.a. the iterative proportional fitting procedure. The stability properties of Sinkhorn bridges when the number of iterations tends to infinity is a very active research area in applied probability and machine learning. Traditional proofs of convergence are mainly based on nonlinear versions of Perron-Frobenius theory and related Hilbert projective metric techniques, gradient descent, Bregman divergence techniques and Hamilton-Jacobi-Bellman equations, including propagation of convexity profiles based on coupling diffusions by reflection methods. The objective of this review article is to present, in a self-contained manner, recently developed Sinkhorn/Gibbs-type semigroup analysis based upon contraction coefficients and Lyapunov-type operator-theoretic techniques. These powerful, off-the-shelf semigroup methods are based upon transportation cost inequalities (e.g. log-Sobolev, Talagrand quadratic inequality, curvature estimates), -divergences, Kantorovich-type criteria and Dobrushin contraction-type coefficients on weighted Banach spaces as well as Wasserstein distances. This novel semigroup analysis allows one to unify and simplify many arguments in the stability of Sinkhorn algorithm. It also yields new contraction estimates w.r.t. generalized -entropies, as well as weighted total variation norms, Kantorovich criteria and Wasserstein distances
Nontuberculous Mycobacterial Lymphadenitis in Children: A French Retrospective Multicenter Study on Epidemiology, Management Strategy and Outcome Over the Last Decade
No full textInternational audienceBackground: Nontuberculous mycobacterial (NTM) adenitis is increasingly recognized in children; however, optimal management strategies remain debated. The aim of this study was to describe the clinical characteristics, management and outcomes of pediatric NTM lymphadenitis in France. Methods: We conducted a multicenter retrospective descriptive study of culture-confirmed NTM lymphadenitis cases in children across 15 French hospitals participating in the MYCOMED network between 2010 and 2019. Results: A total of 279 patients were included, with a progressive increase in diagnoses over the study period, from 11 cases in 2010 to 33 in 2019, with peaks of 38 observed in 2015 and 2018. Most patients were female (64%) with a median age of 3 years. Mycobacterium avium was the most frequently isolated species (71%). Histologic examination revealed necrotizing granulomatous lymphadenitis in two-third of cases (71%, 112/115), and acid-fast bacilli staining was positive in 24.6% (68/276) of the cases. Of the 250 patients with available therapeutic data, 34.8% were treated with surgery alone, 24.8% with antibiotics alone, 28% with combined therapy and 12.4% received no treatment. Overall, 104 children were lost to follow-up. Among 175 patients with follow-up data, the overall cure rate was 96%, with no significant differences between therapeutic strategies. Relapse occurred in 6 children (3.4%). No cases of facial nerve palsy were reported; however, cosmetic sequelae related to scarring were observed. Conclusions: The incidence of pediatric NTM adenitis has increased over the last decade in France, with M. avium as the predominant species. The clinical outcome was favorable in most cases, irrespective of the management strategy. Surgery with complete excision should be considered when technically feasible and safe, while antibiotics or a “wait and see” strategy remain acceptable alternatives
Hyperpolypharmacy in patients with chronic kidney disease and its impact on clinical outcomes
No full textInternational audienceHyperpolypharmacy (≥ 10 daily medications) is frequent in patients with chronic kidney disease (CKD), but its impact remains poorly characterized. This study, based on 3,011 non-dialyzed, non-transplant CKD outpatients from the CKD-REIN cohort (eGFR < 60 mL/min/1.73 m2) aimed to describe drug burden and assess associations between hyperpolypharmacy and adverse outcomes. Drug prescription, kidney function, adverse drug reactions (ADRs), hospitalizations, kidney replacement therapy and deaths before KRT were prospectively recorded over five years. Median age was 69 years and mean eGFR was 34 mL/min/1.73 m2. At baseline, 80% of the cohort had polypharmacy (≥ 5 daily medications), and 33% had hyperpolypharmacy. These rates remained stable over time. Diabetes, dyslipidemia, and a history of cardiovascular and respiratory diseases were the main contributors to hyperpolypharmacy status. Hyperpolypharmacy was associated with greater likelihoods of an ADR (hazard ratio (HR) [95% confidence interval (CI)] 1.21 [1.04-1.40]), hospitalization (HR [95%CI] 1.34 [1.18-1.51]) and death before KRT (HR [95%CI] 1.46 [1.17-1.82]). Among patients with eGFR ≥ 30 mL/min/1.73m2, hyperpolypharmacy also raised the risk of KRT initiation (HR [95%CI] 1.46 [1.00-2.13]), but not in those with eGFR < 30 (HR [95%CI] 0.94 [0.78-1.14]). These results identify hyperpolypharmacy as a significant concern in CKD and underscore the importance of regular medication reviews to reduce adverse outcomes
Complexity of Evaluating GQL Queries
No full textInternational audienceGQL has recently emerged as the standard query language over graph databases, particularly, property graphs. Indeed, this is analogous to the role of SQL for relational databases. Unlike SQL, however, fundamental problems regarding GQL are still unsolved, most notably the complexity of query evaluation. In this paper we provide a complete solution to this problem for the core fragment of GQL and for its extension with path restrictors. In particular, we show that the data complexity of these fragments is P^NP[log]-complete in general, and drops to NL-complete when restrictors are disallowed. Using techniques from embedded finite model theory, we show that this is true, even when the queries use data from infinite concrete domains such as real numbers with arithmetic. In proving these results, we establish and exploit tight connections between GQL and query languages over relational databases, especially extensions of relational calculus with transitive closure operators and fragments of second-order logic