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End-To-End Multi-View Multi-Modal Detection-Driven Image Fusion: One Method to Fuse them all
No full textWe present EDIF, an end-to-end detection-driven framework designed to unify multi-modal and multi-view image fusion within a single architecture. While most existing fusion methods address either spectral complementarity (multi-modal) or viewpoint variability (multi-view) in isolation, real-world perception systems increasingly require both. EDIF formulates fusion as an object-level alignment problem: heterogeneous images are encoded as sets of keypoints, which are matched and aggregated through a graph attention mechanism to form object-centric representations directly optimized for detection. To stabilize training across heterogeneous components, we introduce a three-stage task-driven strategy that progressively aligns keypoint extraction, object localization, and cross-sensor grouping. In addition, we release the Multi-Modal and Multi-View Object Detection Dataset (MMDOD), a new benchmark designed to study detection-driven fusion under strong modality–view dependencies. MMDOD contains over 10,000 images of transparent objects captured under four complementary modalities (visible, NIR, low-contrast, polarization shift) and six viewpoints, with detailed object-level annotations. Experiments on RGB–thermal, multi-camera, and joint multi-modal multi-view benchmarks show that EDIF achieves performance competitive with recent specialized methods, while uniquely operating within a unified framework. On MMDOD, EDIF significantly outperforms adapted multi-modal multi-view baselines, highlighting the benefits of detection-driven, object-level fusion. The proposed MMDOD dataset is publicly available at https://datasets.liris.cnrs.fr/mmdod-version1
Voting with Partial Orders: The Plurality and Anti-Plurality Classes
No full textIn the theory of voting, the Plurality rule for preferences that come in the form of linear orders selects the alternatives most frequently appearing in the first position of those orders, while the Anti-Plurality rule selects the alternatives least often occurring in the final position. We explore extensions of these rules to preferences that are partial orders, offering axiomatic characterisations for them
Space-time evolution of particle emission in pPb collisions at TeV with 3D kaon femtoscopy
No full textInternational audienceThe measurement of three-dimensional femtoscopic correlations between identical charged kaons (KK) produced in pPb collisions at center-of-mass energy per nucleon pair TeV with ALICE at the LHC is presented for the first time. This measurement, supplementary to those in pp and PbPb collisions, allows understanding the particle-production mechanisms at different charged-particle multiplicities and provides information on the dynamics of the source of particles created in pPb collisions, for which a general consensus does not yet exist. It is shown that the measured source sizes increase with charged-particle multiplicity and decrease with increasing pair transverse momentum. These trends for KK are similar to the ones observed earlier in identical charged-pion and KK correlations in PbPb collisions at various energies and in correlations in pPb collisions at TeV. At comparable multiplicity, the source sizes measured in pPb collisions agree within uncertainties with those observed in pp collisions, and there is an indication that they are smaller than those observed in PbPb collisions. The obtained results are also compared with predictions from the hadronic interaction model EPOS~3, which tends to underestimate the source size for the most central collisions and agrees with the data for semicentral and peripheral events. Furthermore, the time of maximal emission for kaons is extracted. It turns out to be comparable with the value obtained in highly peripheral PbPb collisions at the same energy, indicating that the kaon emission evolution is similar to that in pPb collisions
Electroporation of spheroids using an electric field gradient: a tool to study intensity-dependent permeabilization
No full textInternational audienceElectroporation (EPN) is the process by which cell membranes become transiently or permanently permeable upon exposure to pulsed electric fields of suitable intensity and duration. Depending on the pulse parameters, permeabilization can be reversible or irreversible, enabling a wide range of biomedical applications. To improve our understanding of EPN effects on tissues and select efficient treatments and parameters, relevant in vitro tumour models are required. Three-dimensional (3D) cell spheroids have emerged as valuable systems, as they more accurately replicate tumour microenvironment and cell-to-cell interactions than conventional 2D cultures. In this work, we present a new microdevice designed for the culture and gradual electroporation of a population of several hundred uniformly sized spheroids, allowing the systematic study of electroporation over a wide range of electric field intensities within a single experiment. Gradual permeabilization of HT-29 colorectal cancer cell spheroids was performed using a standard electrochemotherapy protocol, and electroporation efficiency was assessed by analysing propidium iodide (PI) uptake. Spheroids were treated with electric fields ranging from 800 V cm−1 to 3400 V cm−1. In toto analysis of PI distribution within spheroids by confocal microscopy revealed highly heterogeneous permeabilization patterns throughout the spheroid volume, for all intensities investigated, even at the highest one of 3400 V cm−1. This study introduces a robust 3D in vitro assay for the systematic evaluation of electroporation-based treatments, providing new insights into the influence of electric field heterogeneity, electrical protocol, and estimation of molecular uptake in the spheroid volume
Modélisation de trajectoires à partir de données non longitudinales à l'aide de l'analyse formelle de concepts
No full textInternational audienceLa modélisation des trajectoires permet de suivre l'évolution d'un phénomène au fil du temps et d'identifier des profils communs d'évolution, notamment dans le contexte des maladies neurodégénératives. Les méthodes classiques reposent sur des données longitudinales, mais leur collecte est souvent complexe et coûteuse. Dans cet article, nous proposons une approche innovante pour extraire des trajectoires à partir de données cross-sectional en utilisant l'Analyse Formelle des Concepts (FCA). Notre méthode transforme les données statiques en une représentation pseudo-temporelle, regroupe les patients en concepts significatifs et génère des trajectoires linéaires sur plusieurs étapes. La progression est ensuite modélisée sous forme d'un graphe de concepts et d'un processus de Markov, où les états sont décrits par les attributs cliniques partagés (intension) et les transitions sont pondérées par une similarité de Jaccard sous contraintes.</div
Dynamical System Modeling in Schizophrenia: A Narrative Review of Computational Psychiatry Frameworks
No full textThis is a preprint of the article submitted to "Dialogues in clinical neuroscience". The published version may differ, from the final version (accepted).The symptom dynamics in schizophrenia often exhibit complex, non-linear temporal patterns, alternating between relatively predictable and disorganized states. Conventional diagnostic frameworks often struggle to capture these evolving dynamics, prompting the development of diverse modeling approaches aimed at describing symptom trajectories more faithfully. Among these approaches, dynamical systems theory provides a particularly powerful framework for addressing temporal dependencies, non-linear interactions, and state-dependent transitions. Recent advances in longitudinal data collection and analysis, including improved temporal resolution and computational methods, now enable both the construction of interpretable models that distinguish distinct trajectories of symptom evolution and the extraction of informative dynamical features. This narrative review synthesizes the growing body of work applying dynamical systems theory to schizophrenia spectrum. It highlights convergent insights across studies while explicitly distinguishing between conceptually motivated models, emerging computational approaches, and empirically validated frameworks. This narrative review also addresses current limitations, including methodological constraints, issues of feasibility, and the need for further longitudinal and clinical validation. The aim is to provide a coherent conceptual framework for understanding schizophrenia as a dynamic process, to promote cross-disciplinary dialogue, and to guide future research in translational computational psychiatry
New Insights on Scalar Promotion with the Polyhedral Model
No full textInternational audienceMemory accesses are a well known bottleneck whose impact might be mitigated by using properly the memory hierarchy until registers. In this paper, we address scalar promotion, a technique to turn temporary arrays into a collection of scalar variables to be allocated to registers. We revisit array scalarization in the light of the recent advances of the polyhedral model. We propose a general algorithm for array scalarization and we show a scalarization of stencil computations thanks to a preliminary preprocessing. Our scalarization algorithm operates on the polyhedral intermediate representation and could be plugged in a polyhedral compiler among other passes. In particular, our scalarization algorithm is parametrized by the program schedule, possibly computed by a previous compilation pass. We present a preliminary experimental validation with promising results
Existence and Regularity of Minimizers for a Plateau Approximation Problem
No full textIn this paper, we study the functional introduced by the author in collaboration with Bonnivard, Bretin, and Lemenant, which is designed to approximate Plateau’s problem. We establish the existence of a minimizer and prove its Hölder regularity. Our results may be viewed as a generalization to higher-dimensional surfaces of the one-dimensional work of Bonnivard, Lemenant, and Millot on the approximation of the Steiner problem
For Generalised Algebraic Theories, Two Sorts Are Enough
No full textGeneralised algebraic theories (GATs) allow multiple sorts indexed over each other. For example, the theories of categories or Martin-Löf type theories form GATs. Categories have two sorts, objects and morphisms, and the latter are double-indexed over the former. Martin-Löf type theory has four sorts: contexts, substitutions, types and terms. For example, types are indexed over contexts, and terms are indexed over both contexts and types. In this paper we show that any GAT can be reduced to a GAT with only two sorts, and there is a section-retraction correspondence (formally, a strict coreflection) between models of the original and the reduced GAT. In particular, any model of the original GAT can be turned into a model of the reduced (two-sorted) GAT and back, and this roundtrip is the identity. The reduced GAT is simpler than the original GAT in the following aspects: it does not have sort equalities; it does not have interleaved sorts and operations; if the original GAT did not have interleaved sorts and operations, then the reduced GAT won't have operations interleaved between different sorts. In a type-theoretic metatheory, the initial algebra of a GAT is called a quotient inductive-inductive type (QIIT). Our reduction provides a way to implement QIITs with sort equalities or interleaved constructors which are not allowed by Cubical Agda. An instance of our reduction is the well-known method of reducing mutual inductive types to a single indexed family. Our approach is semantic in that it does not rely on a syntactic description of GATs, but instead, on Uemura's bi-initial characterisation of the category of (finite) GATs in the 2-category of finitely complete categories with a chosen exponentiable morphism
From additive analysis to process monitoring: characterization of polypropylene solvent-based recycling from plastic feedstocks representative of sorting centres
No full textInternational audienceIn between mechanical and chemical recycling, the recycling by dissolution/precipitation method has emerged as an economically and sustainably viable solution. This work addresses the challenges of this recycling method, particularly those related to the complex and diverse composition representative of polymers feedstocks from sorting centers, from an analytical perspective. We used various analytical tools, ranging from off-line chromatography coupled with high resolution mass spectrometry (LC-HRMS) to in situ spectroscopy, as well as thermal and fractionation analysis, to deeply characterize the plastic feedstocks at different stages of the recycling process. LC-HRMS and thermal gradient interaction chromatography (TGIC) provide valuable insights into the composition of market-available plastics feedstocks and the efficiency of sorting center operations. In situ NIR and Raman spectroscopy allowed real-time monitoring of the dissolution step to ensure complete dissolution, as well as the precipitation step to ensure effective polymer/additive separation. Ex situ attenuated total reflectance infrared spectroscopy (ATR-IR), differential scanning calorimetry (DSC), high temperature size exclusion chromatography (HT-SEC), and LC-HRMS confirmed that the recovered polymer after recycling maintained its properties while removing a fraction of additives. Also, we show that substitution of fossil-based solvents like xylene and decalin is possible by more responsible solvents like amyl acetate or cyclohexanone with comparable dissolution and additives removal performances