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Un dispositif de formation au numérique qui vient questionner l'identité professionnelle enseignante
No full textInternational audienceLa médiation scientifique correspond à un temps nouveau de l’école primaire et témoigne de l’autonomie plus grande du corps enseignant confronté à l’effacement institutionnel. Cette forme pédagogique nécessite cependant des ajustements de la part du corps enseignant. Ce sont des ajustements et leurs impacts sur l’identité professionnelle enseignante que nous questionnons ici. Notre terrain de recherche repose sur le déploiement entre 2016 et 2021 du dispositif Les Filles Qui (LFQ). Une enquête par entretiens auprès d’enseignants ayant accueilli le dispositif a été conduite et permet de mieux comprendre comment l’identité professionnelle des enseignants évolue et est impactée par ce dispositif. Nos résultats mettent en évidence que la médiation scientifique impacte l’identité professionnelle enseignante en invitant à un mode de fonctionnement plus collectif, systémique et plus horizontal. Les reconfigurations sensibles des places et des rôles que la médiation implique, tout en préservant la légitimité des enseignants et enseignantes en fait des individus qui accompagnent le changement et déploient leur capacité d’agir en mobilisant de multiples acteurs, actrices et compétences
Palladium-Catalyzed Cycloadditions towards Nitrogen-containing heterocycles
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Interactive environments for training children’s curiosity through the practice of metacognitive skills : a pilot study
No full textInternational audienceCuriosity-driven learning has shown significant positive effects on students' learning experiences and outcomes. But despite this importance, reports show that children lack this skill, especially in formal educational settings. To address this challenge, we propose an 8-session workshop that aims to enhance children's curiosity through training a set of specific metacognitive skills we hypothesize are involved in its process. Our workshop contains animated videos presenting declarative knowledge about curiosity and the said metacognitive skills as well as practice sessions to apply these skills during a reading-comprehension task, using a web platform designed for this study (e.g. expressing uncertainty, formulating questions, etc). We conduct a pilot study with 15 primary school students, aged between 8 and 10. Our first results show a positive impact on children's metacognitive efficiency and their ability to express their curiosity through question-asking behaviors
Transitional Tensions: Observations from Engineering Education Researchers
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Embedded Imaging Sonar Simulator for AUV Localisation
No full textInternational audienceThis paper presents the new RTAC acoustic simulator aimed at embedded use on low power GPUs. The purpose of this simulator is to be used for relocalisation tasks based on front scan sonars for Autonomous Underwater Vehicles in already mapped environments. Relocalisation is to be achieved by registration of the real and estimated sonar images. The RTAC simulator is implemented using the CUDA programming model for a deployment on NVIDIA Jetson. Geometrical accuracy of the simulator was tested by comparing simulated sonar image with their real counterpart acquired in natural environnements. To simulate comparable sonar images, the environment map used in the simulator was generated by a photogrammetry software from optical images acquired at the same location at the sonar images. Results show good geometrical consistency between the real and simulated sonar images and the simulator is able to compute one frame per second on a Jetson TX2 module which is enough for relocalisation purposes
Sonification of underwater acoustic data: an art-science intiative to explore aquatic life
No full textInternational audienceThe project aims at better understanding the functioning of aquatic ecosystems by using the most advanced 3D sound technologies (Wave Field Synthesis, binaural synthesis...) to design a spatialized audio representation of underwater active acoustics data. This so-called "sonification" process will enable to benefit from the excellent temporal and frequency acuity of the auditory system for the exploration and analysis of echosounder data, whose quantity and complexity still constitute a major challenge. Sonification has initially been tested in artistic contexts, with an emphasis on pedagogy and mediation for the general public: creation of electronic music by students in Hydrography/Oceanography/Acoustics, digital art installations, composition of a string quartet, musical conferences, etc. These various experiments will participate in the elaboration, in a second time, of a tool for sound analysis of underwater active acoustics data, whose scientific relevance and complementarity to traditional analysis methods will have to be validated (signal processing, statistics, data classification algorithms, multi-frequency approaches, visual representations such as echograms, etc.)
THE L 2 -NORM OF THE FORWARD STOCHASTIC INTEGRAL W.R.T. FRACTIONAL BROWNIAN MOTION H > 1 2
No full textIn this article, we present the exact expression of the L 2-norm of the forward stochastic integral driven by the multi-dimensional fractional Brownian motion with parameter 1 2 < H < 1. The class of integrands only requires rather weak integrability conditions compatible w.r.t. a random finite measure whose density is expressed as a second-order polynomial of the underlying driving Gaussian noise. A simple consequence of our results is the exact expression of the L 2-norm for the pathwise Young integral
Lesion Extension and Neuronal Loss after Spinal Cord Injury Using X-Ray Phase-Contrast Tomography in Mice
No full textInternational audienceFollowing spinal cord injury (SCI) the degree of functional (motor, autonomous, or sensory) loss correlates with the severity of nervous tissue damage. An imaging technique able to capture non-invasively and simultaneously the complex mechanisms of neuronal loss, vascular damage, and peri-lesional tissue reorganization is currently lacking in experimental SCI studies. Synchrotron X-ray phase-contrast tomography (SXPCT) has emerged as a non-destructive three-dimensional (3D) neuroimaging technique with high contrast and spatial resolution. In this framework, we developed a multi-modal approach combining SXPCT, histology and correlative methods to study neurovascular architecture in normal and spinal level C4-contused mouse spinal cords (C57BL/6J mice, age 2–3 months). The evolution of SCI lesion was imaged at the cell resolution level during the acute (30 min) and subacute (7 day) phases. Spared motor neurons (MNs) were segmented and quantified in different volumes localized at and away from the epicenter. SXPCT was able to capture neuronal loss and blood–brain barrier breakdown following SCI. Three-dimensional quantification based on SXPCT acquisitions showed no additional MN loss between 30 min and 7 days post-SCI. In addition, the analysis of hemorrhagic (at 30 min) and lesion (at 7 days) volumes revealed a high similarity in size, suggesting no extension of tissue degeneration between early and later time-points. Moreover, glial scar borders were unevenly distributed, with rostral edges being the most extended. In conclusion, SXPCT capability to image at high resolution cellular changes in 3D enables the understanding of the relationship between hemorrhagic events and nervous structure damage in SCI
Experimental evidence of shock wave measurements with low-velocity (<100 m s −1 ) and fast dynamics (<10 ns) capabilities using a coupled photonic Doppler velocimetry (PDV) and triature velocity interferometer system for any reflector (VISAR) diagnostic
No full textInternational audienceWe present a series of shock-wave measurements on aluminum based on the use of a simultaneous Photon Doppler Velocimetry (PDV) and triature velocity interferometer system for any reflector. Our dual setup can accurately measure shock velocities, especially in the low-speed range (<100 m s −1 ) and fast dynamics (<10 ns) where measurements are critical in terms of resolution and unfolding techniques. Especially, the direct comparison of both techniques at the same measurement point helps the physicist in determining coherent settings for the short time Fourier transform analysis of the PDV, providing increased reliability of the velocity measurement with a global resolution of few m s −1 in velocity and few ns FWHM in time. The advantages of such coupled velocimetry measurements are discussed, as well as new opportunities in dynamic materials science and applications
