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Using a soft tensegrity to build an endoscope tip: numerical assessment of orientation and stiffness capabilities
No full textInternational audienc
Short rewriting, and geometric explanations related to the active bijection, for: Extension-lifting bijections for oriented matroids, by S. Backman, F. Santos, C.H. Yuen, arXiv:1904.03562v2 (October 29, 2023)
No full textFor an oriented matroid M , and given a generic single element extension and a generic single element lifting of M , the main result of [1] provides a bijection between bases of M and certain reorientations of M induced by the extension-lifting. This note is intended to somehow clarify and precise the geometric setting for this paper in terms of oriented matroid arrangements and oriented matroid programming, to describe and prove the main bijective result in a short simple way, and to show how it consists of combining two direct bijections and a central bijection, which is the same as a special case -practically uniform -of the bounded case of the active bijection [5, 6]. (The relation with the active bijection is addressed in [1] in an indirect and more complicated way.
Spectral decomposition unlocks ascidian morphogenesis
No full textInternational audienceDescribing morphogenesis generally consists in aggregating the multiple high resolution spatiotemporal processes involved into reproducible low dimensional morphological processes consistent across individuals of the same species or group. In order to achieve this goal, biologists often have to submit movies issued from live imaging of developing embryos either to a qualitative analysis or to basic statistical analysis. These approaches, however, present noticeable drawbacks, as they can be time consuming, hence unfit for scale, and often lack standardisation and a firm foundation. In this work, we leverage the power of a continuum mechanics approach and flexibility of spectral decompositions to propose a standardised framework for automatic detection and timing of morphological processes. First, we quantify whole-embryo scale shape changes in developing ascidian embryos by statistically estimating the strain-rate tensor field of its time-evolving surface without the requirement of cellular segmentation and tracking. We then apply to this data spectral decomposition in space using spherical harmonics and in time using wavelets transforms. These transformations result in the identification of the principal dynamical modes of ascidian embryogenesis and the automatic unveiling of its blueprint in the form of spectograms that tell the story of development in ascidian embryos
A Dance Performance with a Humanoid Robot using a Real-time Gesture Responsive Framework
No full textInternational audienceWe present a lightweight, real-time gesture responsive framework designed to investigate dynamics of human-robot interaction in live dance performances, merging aspects from choreography and robotics. In particular, it is tailored for artists to integrate human-sized humanoid robots into their dances seamlessly, offering an intuitive solution without the complexities of mastering robot control systems. Unlike existing interaction methods relying on wearable sensors or predetermined music cues, our framework, integrated in a task-space controller, enables the robot to dynamically respond to the dancer’s movements, generating unpredictable yet artistically meaningful gestures without the need for body-mounted sensors. This design choice emphasizes the artistic intention behind the improvisation, illustrating that it is not merely about creating movements spontaneously but rather a way of expression in intuition guided by perception. We assess our framework on the HRP-4 humanoid robot and the result has been successfully demonstrated in a public human-robot dance performance at the Arts Center of Enghien-les-Bains’s 23/24 season launch event, aiming to contribute to the exploration of co-creation between human and human-sized humanoid robot in improvised dance performances
Coarse-to-Fine Concept Bottleneck Models
No full textInternational audienceDeep learning algorithms have recently gained significant attention due to their impressive performance. However, their high complexity and un-interpretable mode of operation hinders their confident deployment in real-world safety-critical tasks. This work targets ante hoc interpretability, and specifically Concept Bottleneck Models (CBMs). Our goal is to design a framework that admits a highly interpretable decision making process with respect to human understandable concepts, on two levels of granularity. To this end, we propose a novel two-level concept discovery formulation leveraging: (i) recent advances in vision-language models, and (ii) an innovative formulation for coarse-to-fine concept selection via data-driven and sparsity-inducing Bayesian arguments. Within this framework, concept information does not solely rely on the similarity between the whole image and general unstructured concepts; instead, we introduce the notion of concept hierarchy to uncover and exploit more granular concept information residing in patch-specific regions of the image scene. As we experimentally show, the proposed construction not only outperforms recent CBM approaches, but also yields a principled framework towards interpetability
PneuNet Actuators Design: Trade-offs between Deformation, Force, and Resistance to Buckling
No full textSoft pneumatic network (PneuNet) actuators and their derived grippers have gained prominence in industrial and medical applications. The performance of PneuNets is typically assessed based on their angular deformation and the tip force they exert. To enhance their effectiveness, several studies have investigated the relationship between design parameters and these critical performance metrics. This paper expands upon existing literature by examining the impact of design parameters on three performance metrics: angular deformation, tip force, and resistance to buckling—the latter proposed for the first time as a performance metric for PneuNets. Resistance to buckling is significant in applications requiring high forces with minimal restrictions on maximum allowable pressure. The angular deformation and tip force are analyzed by introducing additional design parameters previously unexplored in the literature. Moreover, the former is studied in three different configurations. In this context, the configuration of the PneuNet actuator refers to its orientation, such as horizontal or vertical fixation, and whether it bends against or towards gravity. These configurations simulate environmental factors and the diverse positions that PneuNets may encounter in practical applications. It is demonstrated that the influence of some design parameters on angular deformation is configuration-dependent. Furthermore, a comprehensive table is provided to aid users in optimizing PneuNet performance—whether in terms of angular deformation, tip force, or resistance to buckling—according to specific application requirements. Finally, to evaluate the practical applications of these performance metrics, five PneuNet grippers with different shapes are fabricated and tested in two distinct gripping modes
In-memory-computing implementation of magnetoresistive networks for ultra-low-power computing
No full textPartenaires FOTONINLC2NIESInternational audienc
Micro‐CT and high‐field MRI for studying very early post‐mortem human fetal anatomy at 8 weeks of gestation
No full textInternational audienceObjective: This study involved very early post‐mortem (PM) examination of human fetal anatomy at 8 weeks of gestation (WG) using whole‐body multimodal micro‐imaging: micro‐CT and high‐field MRI (HF‐MRI). We discuss the potential place of this imaging in early first‐trimester virtual autopsy. Methods: We performed micro‐CT after different contrast‐bath protocols including diffusible iodine‐based contrast‐enhanced (dice) and HF‐MRI with a 9.4 T machine with qualitative and quantitative evaluation and obtained histological sections. Results: Nine fetuses were included: the crown–rump length was 10–24 mm and corresponded to 7 and 9 WG according to the Robinson formula. The Carnegie stages were 17–21. Dice micro‐CT and HF‐MRI presented high signal to noise ratio, >5, according to the Rose criterion, and for allowed anatomical phenotyping in these specimens. Imaging did not alter the histology, allowing immunostaining and pathological examination. Conclusion: PM non‐destructive whole‐body multimodal micro‐imaging: dice micro‐CT and HF‐MRI allows for PM human fetal anatomy study as early as 8 WG. It paves the way to virtual autopsy in the very early first trimester. Obtaining a precision phenotype, even regarding miscarriage products, allows a reverse phenotyping to select variants of interest in genome‐wide analysis, offering potential genetic counseling for bereaved parents
Insights into the evolution, virulence and speciation of Babesia MO1 and Babesia divergens through multiomics analyses
No full textAll datasets generated for the current study are accessible in the NCBI/SRA repository under Bioproject PRJNA1032622 (reviewer link). Specifically, the datasets include PacBio HiFi reads (SRA accession number SRR26661633), B. MO1 genome, RNA-Seq (SRA accession number SRR26661632), Hi-C reads (SRA accession number SRR26661630, SRR26661631), ChIP-Seq reads (SRA accession number SRR26661627, SRR26661629, SRR26661626, SRR26661628, SRR26661625).The Babesia MO1 genome was processed using the gene annotation pipeline FunAnnotate v1.8.9 (https://github.com/nextgenusfs/funannotate) and PAP (https://github.com/kjestradag/PAP) pipelines. FunAnnotate was supplied with the MO1 IsoSeq isoforms computed above, along with protein sets of B. bigemina, B. bovis, B. microti, P. falciparum, Toxoplasma gondii, T. orientalis, T. parva and all UniProt/SwissProt protein models. Functional annotations were obtained using InterProScan v5.55-88 with default parameters. For B. divergens Rouen 87, gene annotations were transferred to the improved assembly presented here using the PATT pipeline (https://github.com/kjestradag/PATT). Gene models form B. MO1 were constructed based on annotations of evolutionarily-related species and further refined using PacBio Iso-seq data specific to B. MO1.Babesia MO1, B. divergens Rouen 87 and a B. divergens clinical isolate from Spain were cultured using human A+ blood obtained from healthy volunteer donors [Citation6]. The blood was sourced from the American red cross (US), the Interstate Blood Bank (US), or the Blood Transfusion Center (Spain), adhering to approved protocols and in compliance with the relevant institutional guidelines and regulations.International audienceBabesiosis, caused by protozoan parasites of the genus Babesia, is an emerging tick-borne disease of significance for both human and animal health. Babesia parasites infect erythrocytes of vertebrate hosts where they develop and multiply rapidly to cause the pathological symptoms associated with the disease. The identification of new Babesia species underscores the ongoing risk of zoonotic pathogens capable of infecting humans, a concern amplified by anthropogenic activities and environmental changes. One such pathogen, Babesia MO1, previously implicated in severe cases of human babesiosis in the United States, was initially considered a subspecies of B. divergens, the predominant agent of human babesiosis in Europe. Here we report comparative multiomics analyses of B. divergens and B. MO1 that offer insight into their biology and evolution. Our analysis shows that despite their highly similar genomic sequences, substantial genetic and genomic divergence occurred throughout their evolution resulting in major differences in gene functions, expression and regulation, replication rates and susceptibility to antiparasitic drugs. Furthermore, both pathogens have evolved distinct classes of multigene families, crucial for their pathogenicity and adaptation to specific mammalian hosts. Leveraging genomic information for B. MO1, B. divergens, and other members of the Babesiidae family within Apicomplexa provides valuable insights into the evolution, diversity, and virulence of these parasites. This knowledge serves as a critical tool in preemptively addressing the emergence and rapid transmission of more virulent strains
Assistance à l’ingénierie de logiciels pour mieux protéger la vie privée des utilisateurs
No full textPrix du meilleur poster du GdR GPL 2024National audienceAlors que les systèmes logiciels deviennent de plus en plus personnalisés pour les utilisateurs,la collecte et l’exploitation des données personnelles ont atteint des niveaux sans précédent.Cette évolution souligne un problème critique sur la protection de la vie privée des utilisateurs.Le respect de réglementations en matière de protection des données personnelles, comme lerèglement général européen sur la protection des données (RGPD), est devenu une nécessitéjuridique. Malgré les obligations légales, il subsiste un manque de méthodes universellementacceptées pour intégrer la gestion de la vie privée dans les applications. Pour aider lesdéveloppeurs, notre objectif principal est d'introduire une approche d'ingénierie logicielleoutillée qui intègre des fonctionnalités de protection des données personnelles dans lesapplications existantes, les rendant ainsi respectueuses de la vie privée. La particularité de notreproposition réside dans son caractère actionnable, qui va au-delà d’une simple descriptiondéclarative de la régulation. Notre travail consiste à présenter les fondements de cette approche : le métamodèle PRIAM (Privacy Assessment Model) et ses artefacts associés. PRIAMmodélise le RGPD en capturant les concepts décrits dans le règlement. Ce métamodèle sert debase à divers artefacts (user stories génériques, schéma de BD) qui s'adaptent à toute applicationspécifique qui nécessite de tenir compte du respect de la vie privée. Notre approche comprendun langage spécifique au domaine (DSL) dérivé du métamodèle PRIAM, des user storiesadaptées à l'application spécifique et une base de données qui stocke à la fois les donnéesspécifiques à l'application et à l'utilisateur nécessaires à la mise en œuvre des droits desutilisateurs en matière de respect de la vie privée.Notre approche se veut non-intrusive sur l'application du fournisseur des traitements. Pour cela,nous avons élaboré un protocole de contrôle d'accès (gestion de l'authentification et desautorisations) et de gestion des consentements externalisé, s'appuyant sur le paradigme ABAC(Attribute-Based Access Control) avec le patron d'architecture des side-cars pour impacter auminimum l'application du fournisseur