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Straining the root on and off triggers local calcium signaling
No full textThroughout their life, plant root are submitted to mechanical stresses due to pressure exerted by the soil. So far, few studies addressed root cell deformation and calcium signaling elicited by soil compression. In this study, we designed a microchip inspired by pneumatic microvalve concept in order to deliver a lateral pressure to the root of a plant expressing the RGECO1-mTurquoise calcium reporter. Lateral pressure applied on the root induced a moderate elastic deformation of root cortical cells and elicited a multicomponent calcium signal at the onset of the pressure pulse, followed by a second one at the release of the pressure. This indicates that straining rather than stressing of tissues is relevant to trigger the calcium signal. The calcium elevation was restricted to the tissue under pressure and did not propagate. Additionally, the calcium signals exhibited a remarkable attenuation upon repetitive stimulations. Highlights - A microvalve concept mimicking lateral soil pressure was developed. - Non-damaging lateral compression of the root induces an elastic deformation of cortical cells. - A multicomponent calcium signal is elicited at the onset of a pressure pulse and upon release of the pressure. - Straining rather than stressing of tissues is relevant to trigger the calcium signal. - The calcium signal is localized at the tissue under pressure and does not propagate. - Calcium signals exhibit a remarkable attenuation upon repetitive stimulations
EXTRACTING FOOD-FERMENTATION KNOWLEDGE USING AN NER FRAMEWORK FROM BIOLOGICAL AND CHEMICAL DOMAINS WITH LLM-ASSISTED SILVER ANNOTATIONS
No full textInternational audienceThe food-fermentation literature contains rich knowledge of microorganisms, compounds, and processing conditions, making it a valuable source for data-driven analysis, yet named entity recognition (NER) methods for this domain remain underexplored due to the lack of annotated data. To systematically extract fermentation-relevant knowledge from the literature, we adopt a generative, self-correcting NER framework from our previous work as the core extraction model and investigate its applicability to the food-fermentation domain. To enable evaluation under this data-scarce setting, we further explore the use of large language model-assisted annotation to construct a silver corpus for food-fermentation NER. We design a prompt-based pipeline to annotate 2,500 PubMed abstracts, yielding over 23,000 fermentation-related entities. By comparing the silver annotations with expert-labeled data in the Florilege dataset, we quantify the quality of the silver corpus, obtaining an F1 score of 60.3. We further evaluate the NER framework on the silver test set under three different initialization settings, corresponding to biological data, chemical data, and the silver corpus. The results demonstrate that the NER framework from our previous work can be effectively adapted to the foodfermentation domain, achieving its strongest and most stable performance with biological initialization, while silver-based training remains a viable option despite annotation noise.</div
Colouring the interference digraph of a set of requests in a bidirected tree
No full textIn this paper, we investigate the impact of the broadcast effect arising in filterless optical networks on the computational complexity of the wavelength assignment problem. We model conflicts using an appropriate interference digraph, whose proper colourings correspond to feasible wavelength assignments. Minimizing the number of required wavelengths therefore amounts to determining the chromatic number of this interference digraph. Within this framework, we first present a polynomial-time 2-approximation algorithm for minimizing the number of wavelengths. We then show that the problem is fixed-parameter tractable when parameterized by the number of available wavelengths. We also derive polynomial-time algorithms for computing the independence and clique numbers of this interference digraph
Développement d’un formulaire machine-actionnable pour la gestion FAIR des logiciels de recherche dans les plans de gestion de projet
No full textSoftware has become one of the fundamental pillars of research, on par with publications and data. Yet despite this central role, research software remains difficult to find, cite, and reference properly. In the absence of appropriate mechanisms, software is often overlooked or poorly described in data management plans. To address this challenge, a form dedicated to source code and research software has been integrated into the DMP OPIDoR platform. It enables the description of software and its associated research data within a single plan. Designed in accordance with the FAIR principles and intended to be machine-actionable, this form accounts for the specific characteristics of the source code and software lifecycle. It covers key aspects such as general software description, development tools and execution environments, preservation (referencing and long-term archiving), legal considerations (authors, licenses), and the scientific valorisation of software outputs.Les logiciels constituent aujourd’hui l'un des piliers fondamentaux de la recherche, au même titre que les publications et les données. Pourtant, malgré leur rôle central, les logiciels de recherche restent difficiles à trouver, à citer et à référencer correctement. En raison de l'absence de mécanismes appropriés, les logiciels sont souvent négligés ou mal décrits dans les plans de gestion des données. Pour répondre à ce défi, un formulaire dédié aux codes sources et logiciels de recherche a été intégré dans la plateforme DMP OPIDoR. Il permet de décrire les logiciels et les données de recherche associées au sein d’un même plan. Conçu selon les principes FAIR et exploitable par machine, ce formulaire prend en compte les spécificités du cycle de vie des codes sources et logiciels. Il aborde des aspects clés tels que la description générale du logiciel, les outils de développement et environnements d’exécution, la préservation (référencement et archivage pérenne), les questions juridiques (auteurs, licences), ainsi que la valorisation scientifique des productions logicielles
Cause végétale. Coopérer avec les plantes pour se nourrir
No full textInternational audienceLa « cause végétale » serait-elle un impensé de la transition agroécologique et alimentaire ? Cause végétale et cause paysanne sont-elles les deux versants d’une même exigence ? Cet ouvrage fait le pari que cette question, encore peu explorée, conditionne à la fois la reconnaissance des plantes comme êtres de relation et l’adoption de pratiques aujourd’hui indispensables pour fonder des solutions « avec » la nature. À travers l’affirmation d’une éthique du travail vivant, il met en lumière les chaînes d’interdépendances et de sociabilités basées sur la coopération entre humains et non-humains dans les activités productives.Issu du projet PlantCoopLab (Plant Cooperation Laboratory), cet ouvrage repose sur une recherche collective menée pendant cinq ans. Il s’appuie sur une démarche interdisciplinaire en sciences humaines et sociales d’une part et transdisciplinaire d’autre part, développée en interaction avec des travailleurs des plantes, cultivateurs et cueilleurs. Les contributions mobilisent des approches anthropologiques, éthiques, politiques et sociologiques qui permettent de repenser la place de ces métiers dans une agriculture respectueuse du vivant.L’ouvrage s’adresse aux chercheurs et universitaires, ainsi qu’aux acteurs de la société civile, aux professionnels et aux décideurs dans les secteurs de l’agriculture, de l’alimentation et de l’environnement
Vers une modélisation semi-distribuée pour la simulation des étiages : comparaison de quatre modèles hydrologiques sur le bassin de la Meuse française
No full textLes sécheresses sont une préoccupation croissante pour les gestionnaires de l’eau, avec la perspective d’événements plus sévères et plus fréquents. La bonne prévision de ces épisodes est cruciale pour en atténuer les conséquences. La modélisation hydrologique semi-distribuée, en découpant le bassin versant en mailles interconnectées, permet de modéliser des débits à des points jaugés et non jaugés et de prendre explicitement en compte les variabilités spatiales observées sur le bassin. Dans cette étude, quatre modèles semi-distribués sont mis en place sur le bassin de la Meuse à Chooz, territoire qui présente des caractéristiques géologiques, topographiques et météorologiques contrastées. À l’issue d’un exercice de calage commun, les modèles fournissent des résultats cohérents en termes de débits sur l’ensemble du bassin et comparables aux résultats de modélisations globales à l’exutoire à Chooz. Des biais analogues sont observés entre les modèles, pouvant refléter des limites structurelles communes, des incertitudes sur les mesures de débits ou sur les forçages météorologiques. L’exercice sur l’étiage 2022 met en évidence une variabilité des débits d’étiage simulés, liée notamment au choix du modèle et à la météorologie utilisée pour son calage. Une perspective de développement pour améliorer la simulation des étiages consiste à affiner la compréhension des stocks et des écoulements souterrains puis leur représentation dans les modèles hydrologiques
Complexity of Consistency Testing for the Release-Acquire Semantics
No full textInternational audienceIn a seminal work, Gibbons and Korach [10] studied the complexity of deciding whether an observed sequence of reads and writes of a multi-threaded program admits a sequentially consistent interleaving. They showed the problem to be NP-hard even under strong syntactic restrictions. More recently, Chakraborty et al.[7] considered the problem for weak memory models and proved that NP-hardness remains even when the number of threads, the number of memory locations, and the value domain are all bounded.In this paper we revisit the problem for the release-acquire variants of the C11 memory model. Our main positive result is that consistency testing can be done in polynomial-time when each memory location is written by at most one thread (multiple readers are allowed). Notably, this restriction is already NP-hard for sequential consistency. We complement this upper bound with tight hardness results: the problem is NP-hard when two threads may write to the same location, and allowing three writers per location rules out 2 o(k) • n O(1) algorithms under the Exponential Time Hypothesis, where k denotes the number of threads, and n the number of memory operations
Light antiproton-nucleus systems at low energies with the ab initio NCSM/RGM method
No full textInternational audienceThe availability of low-energy antiproton beams at the CERN Antiproton Decelerator has renewed interest in using antimatter as a probe of nuclear structure and in forming exotic antiprotonic few-body systems. In this work, we extend the ab initio No-Core Shell Model combined with the Resonating Group Method (NCSM/RGM), which was successfully applied to light-nucleus structure and reactions, to antiproton-nucleus dynamics at low energies. The NCSM/RGM formalism is adapted to antiproton projectiles by removing the requirement of antisymmetrization under exchange of target and projectile constituents, while retaining a fully microscopic description of the nuclear target and the relative motion. We focus on the lightest systems, , , and , for which benchmarking against exact solutions of the Schrödinger equation enables stringent validation and helps disentangle methodological uncertainties -- e.g., those associated with the choice of configurations included in the NCSM/RGM expansion -- so that the dominant residual uncertainty can be attributed to the interaction. We compute phase shifts, scattering lengths, cross sections, antiprotonic-atom level shifts and widths, nuclear quasi-bound energies, and annihilation densities. We find that the hard short-range components of the meson-exchange-based interaction lead to slow convergence of the NCSM/RGM kernels expanded in a harmonic-oscillator basis, requiring exceptionally large model spaces and posing significant numerical challenges. We discuss practical strategies to mitigate these limitations and assess the impact of missing closed-channel configurations, which is a significant source of uncertainties in very light systems
Evidence of production with the ATLAS detector
No full textInternational audienceThis paper presents the first evidence of the simultaneous production of two bosons and one photon with the ATLAS detector at the Large Hadron Collider. The measurement is performed using the full Run-2 dataset, recorded from 2015 to 2018, of proton-proton collisions at a center-of-mass energy of TeV, corresponding to an integrated luminosity of fb. The fully leptonic final state with four leptons and one photon is analyzed, with or . This final state is measured in a fiducial region where photon final-state radiation is minimized, and the photon has a transverse momentum of GeV. Eight events are selected, with a background estimate of . This results in an observed (expected) significance of the final state of (). The measured cross-section for in the fiducial region is , in agreement with the predicted Standard Model one, fb
ASR impacts on the behaviour of mortar submitted to a pull-out test inside a X-ray tomograph
No full textInternational audienceMulti-scale and multi-physics processes make understanding the mechanical impact of alkali-silica reaction (ASR) on structure challenging.This study investigates ASR's impact on a small-scale mortar foundation subjected to reinforcement pull-out.A 1/50 scale electrical pylon foundation is tested in an X-ray tomograph at different ASR swelling stages. Finite-element-based digital volume correlation is used to analyze the structure’s behavior during loading.Results show that the pull-out resistance of small-scale foundations increases with ASR and the failure patterns change. Through measurements of displacements within the mortar, interfacial debonding, and multidirectional swelling, this increase is attributed to reinforcement prestressing caused by ASR swelling.In-situ tests combined with Digital Volume Correlation allow for precise quantification of three-dimensional displacement fields in the specimen. Such a method highlights the effects of alkali-silica reaction, enabling a quantified understanding of the relationship between structural response and pathology progression