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Primality Tests and Prime Certificate
No full textThis note presents a formalisation done in Coq of Lucas-Lehmer test and Pocklington certificate for prime numbers. They both are direct consequences of Fermat little theorem. Fermat little theorem is proved using elementary group theory and in particular Lagrange theorem
Fraygui Abdallah, Moubine Abdallah et Gay Vincent, <i>Des vies pour l’égalité. Mémoires d’ouvriers immigrés</i>
No full textInternational audience[Référence : Fraygui Abdallah, Moubine Abdallah et Gay Vincent, Des vies pour l’égalité. Mémoires d’ouvriers immigrés. – Paris : Éditions Syllepse, 2023. – 168 p. ISBN : 979-10-399-0102-4
Fault segmentation, geometry and recent activity in the epicentral area of the 1956 Mw 7.5 Amorgos earthquake (Greece)
No full textInternational audienceThe Amorgos-Santorini region (Hellenic Volcanic Arc, Greece), suffered the most powerful earthquake in the Mediterranean in the 20th century (1956, Mw ~7.5). This event caused casualties, severe damage and a large tsunami. The epicentral area is offshore and is characterized by several basins bounded by submarine faults accommodating back-arc extension and the Anatolian extrusion. Recently, the Amorgos fault was identified as the causative fault of the 1956 Amorgos earthquake. However, the characteristics of this fault, such as its detailed geometry, segmentation and kinematics remain unclear and debated. Using new high-resolution bathymetric data and sediment cores, we present a detailed mapping of this fault and its neighbors.The Amorgos fault is composed of three segments separated by relay zones. Taking into account the onshore geology, where E-W striking late Miocene normal faults are mapped, the segmentation could be controlled by structural heritage. Offshore, all but the southernmost segments of the Amorgos fault exhibit cumulative scarps of at least 700 m in relief. The segments strike NE-SW, except for the northern one that displays a curved structure in its middle, at 60° with respect to the main fault (E-W striking).The central segment, where evidences of the 1956 earthquake rupture were found, is composed of several secondary faults that offset young geomorphic features at the seafloor (such as mass-wasting scars) with purely normal kinematics. In comparison, the curved northern segment shows fewer secondary faults, none of them offsetting the numerous mass-wasting scars observed along its trace. We also find here secondary NE-SW faults that are crosscutting its cumulative scarps, and are offsetting the Last Glacial Maximum wave-cut platform by up to 5 meters, testifying for their recent activity. These observations question the role of the northern E-W striking segment in the accommodation of the present-day stress regime (NW-SE extension), that may be now inactive, or activated as a strike-slip fault, although we do not observe markers laterally offset. We discuss how the geometry and segmentation of the Amorgos fault can impact the rupture propagation, especially in relation to the 1956 earthquake and morphology of the nearby faults
Dosimetry Computation Based on Near-Field Measurements on a Huygens Box Surrounding the Antenna
No full textInternational audienceThis article presents a new technique for dosimetry assessment in realistic environments based on free-space EM-fields' measurements around the antenna thanks to a RF phasor array embedded in an EM scanner. These measured EM-fields are used in the simulation as a Huygens' box source to model the radiation from the EM-device. Note that in practice -except for the manufacturers of the EM device- the challenge is that we do not know the full details of the EM-device concretely. Such knowledge is necessary in any simulation process containing the device. The coupling of RF phasor near-field measurements with simulations (augmented measurements) are done by keeping a turned off simplified replica of the EM-device inside the Huygens' box to model the interactions between the human model and the EM-device (e.g., scattering and diffraction). Numerical simulations are done with the Finite Integration Technique (FIT) to test the accuracy and validity of the proposed approach
Cancer-associated loss-of-function mutations in KCNQ1 enhance Wnt/β-catenin signalling disrupting epithelial homeostasis
No full textInternational audienceIon channels are emerging as regulators of intracellular signalling pathway, yet the molecular mechanisms underlying this role remain poorly understood. KCNQ1, a potassium channel with tumour suppressor functions, restricts Wnt/β-catenin signalling, a pathway whose dysregulation, often driven by protein-altering mutations, is a hallmark of several epithelial cancers. Here, we identify loss-of-function (LOF) mutations in KCNQ1 across multiple epithelial cancers and elucidate their impact on Wnt/β-catenin signalling. Our findings reveal that cancer-associated KCNQ1-LOF mutations regulate the β-catenin pathway through a dual mechanism. First, they drive β-catenin transcriptional activity through triggering MET receptor, bypassing Frizzled/LRP6 receptor complex activation. Second, these mutations suppress the expression of key negative regulators of Wnt signalling, such as DKK-1, Wif-1 and NKD-1, leading to amplified pathway activation in response to Wnt ligand stimulation. This dysregulation disrupts epithelial homeostasis, as demonstrated by impaired crypt organization and increased proliferation in mouse colon-derived organoids. Together, these findings uncover an original mechanism linking KCNQ1 dysfunction to aberrant Wnt/β-catenin signalling, highlighting the role of ion channel in regulating epithelial signalling networks and tissue homeostasis
Revisiting Behavioral Merger Remedies in Turbulent Markets: A Framework for Dynamic Competition
No full textIlmenau Economics Discussion Papers, Vol. 30, No. 202Digital platforms, ecosystems, and R&D intensive sectors pose distinctive challenges for merger control. In these fast-evolving markets, shaped by technological change and shifting competitive dynamics, traditional ex-ante reviews often fall short in anticipating long-term outcomes. This paper proposes a multi-step merger control model that includes a mechanism for remedy revision, allowing authorities to adjust behavioral commitments during their implementation. By embedding structured flexibility into merger decisions, our approach enables remedies to evolve in response to market reconfigurations, strategic conduct, or regulatory insights. The framework aims to ensure that remedies remain proportionate, effective, and legally predictable. By bridging ex-ante assessment and ex-post adaptation, it offers a policy instrument better suited to the uncertainties of dynamic competition
IA et collectivités territoriales: Usages, enjeux et défis
No full textInternational audienceLes collectivités territoriales s’emparent progressivement des outils d’IA, souvent de façon expérimentale, pour améliorer la qualité des services rendus aux citoyens, mettre en place des politiques publiques, faciliter le travail en interne des agent·es, etc. Si à ce jour la percée de l’IA dans les collectivités reste timide, la tendance est au déploiement progressif à moyen et à plus long terme. En ce début d’année 2025, quelle est la place accordée à l’IA dans les politiques publiques territoriales ? Quels sont les usages concrets, les opportunités et les résistances au sein des collectivités ? Comment sont pris en considération les enjeux liés à l’attractivité du territoire, aux transformations des métiers des agent·es, à la participation citoyenne ? Cette journée d’étude propose de mettre l’accent sur les questionnements émergents, des expérimentations en cours et des premiers acquis sur le sujet en cherchant à croiser les points de vue des professionnel·les, des élu·es, des citoyen·nes et des chercheur·es
