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Droit du numérique [Chronique]
No full textNational audienceLa matière reste abondante tant au niveau des nouveaux textes adoptés que des décisions rendues. De manière désordonnée, des textes d'importance sont intervenus sur plusieurs aspects du secteur numérique, témoignant de l'état encore éclaté du droit sur la question. L'étude de la jurisprudence permet de revenir sur la question de la qualification de la mise à disposition de copie de logiciel ou encore sur l'adaptation de l'exception de copie privée aux évolutions numériques et sur la lutte contre la contrefaçon en ligne. Les décisions interrogent également la qualité des acteurs, qu'il s'agisse du contrôleur d'accès ou du fournisseur d'hébergement.Comme dans les précédentes livraisons, ce panorama, qui accueille désormais les professeurs Amélie Favreau et Nicolas Binctin, sera consacré à certains aspects législatifs et jurisprudentiels des évolutions du droit du numérique d'octobre 2023 à octobre 2024 sans prétendre à l'exhaustivité
Anticipatory muscle activations to coordinate balance and movement during motor transitions: A narrative review
No full textInternational audienceBackground: Maintaining balance while moving is vital for day-to-day activities. A key challenge in the comprehension of human movement is to determine how muscles contribute to balance-movement coordination. Motor transitions, defined as movements executed between two steady balance states, are particularly interesting phases to study balance-movement coordination because a large, discrete change in whole-body momentum may disturb balance. During voluntarily-initiated motor transitions, anticipatory muscle patterns provide the biomechanical conditions that are favourable to both maintaining balance and executing the movement.Research question: What are the mechanical consequences of anticipatory muscle activations for balance-movement coordination during voluntarily-initiated motor transitions?Methods: We review the biomechanical contributions of the anticipatory muscle activations identified in the literature during four types of voluntarily-initiated motor transitions, through the prism of three balance mechanisms (‘moving the centre of pressure (CoP)’, ‘counter-rotating segments’, and ‘applying new external force(s)’). In particular, we investigate how anticipatory muscle activations modulate whole-body centre of mass acceleration.Results:We show that the mechanical consequences of anticipatory muscle activations have been extensively described, but mainly using the ‘moving the CoP’ mechanism. Unlike their role during steady balance states, both ‘moving the CoP’ and ‘applying new external force(s)’ mechanisms create a required mechanical instability during the anticipatory phase of motor transitions. The ‘counter-rotating’ mechanism may act as a stabiliser during motor transitions, but additional research is needed to clarify this assumption.Significance: This review establishes that muscle activation processes have different mechanical consequences for balance-movement coordination during the anticipatory phases of motor transitions, compared to steady balance states. Because the mechanical instability that is created can lead to falls, a better understanding of the mechanisms underlying motor transitions is needed to enable the design of more effective fall prevention programs and/or devices for population with balance deficits
Décomposer la variation morphologique avec le package prWarp : quelles applications pour l’étude des primates humains et non-humains ?
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L'écriture de la pensée postcoloniale
No full textTable Ronde 1 – Travail de MémoireInternational audienc
Le recours à la visioconférence en procédure pénale, point trop n'en faut !
No full textInternational audienceÉtude d'une série d'arrêts rendus par la chambre criminelle de la Cour de cassation à propos du recours à la visioconférence dans le cadre de la procédure pénale.Le développement du recours à la visioconférence dans la procédure pénale génère un contentieux nourri depuis plusieurs années, montrant le souci de parvenir à un équilibre entre efficacité du système judiciaire et respect des droits fondamentaux. Plusieurs arrêts rendus tout récemment confirment à la fois la diversité des questions posées, l’absence de neutralité du recours à la technologie et la nécessité d’adapter le droit dans ce contexte
Balance analysis of autistic children during beam walking
No full textInternational audienceAutism Spectrum Disorder (ASD) is characterised by persistent deficits in communication and social interaction, as well as restricted, repetitive patterns of behaviour, interests, or activities. Although not included among the diagnostic criteria, motor disorders are also part of the clinical phenotype of ASD, and their origins are largely under-researched (Mosconi et al., 2015). Among these motor disorders, specificities in postural control and gait initiation have been identified (Benchekri et al., 2023), suggesting that balance mechanisms are impacted by ASD. Walking on a narrow beam requires the ability to maintain balance with a reduced base of support (BoS) along the medio-lateral (ML) direction. When balance is challenged, humans can use various strategies to increase stability, such as increasing the size of the BoS to enhance the whole-body centre of mass (CoM) shifts and/or rotating segments to modulate whole-body angular momentum (AM) (Hof, 2007). To rely on the “extend the BoS” strategy is limited when walking on a beam. Authors have shown that the main stabilisation strategy during this type of task focuses on regulating the AM of different body parts (Chiovetto et al., 2018) and also that a significant active control is required to stabilise motion especially along the ML axis (Bauby & Kuo, 2000). Assuming that children with ASD exhibit unique balance characteristics in motor tasks, it is important to explore the extent of their particularities by analysing their performance during challenging balance tasks such as beam walking
New data on morphological evolution and dietary adaptations of Elephas recki from the Plio-Pleistocene Shungura Formation (Lower Omo Valley, Ethiopia)
No full textInternational audienceThe abundant and diverse proboscideans are essential terrestrial megaherbivores for studying morphological adaptations and reconstructing paleoenvironments in Africa. This new study of the lineage of Elephas recki from the Plio-Pleistocene deposits of the Shungura Formation aimed at investigating further the interplay between morphological and behavioral adaptations within proboscideans. For this, we used the most complete and well-preserved third molars of the series for characterizing morphological changes, while describing dietary behavior by applying mesowear angle analysis to all identifiable cheek teeth. Biometric character changes indicated that evolutionary change was not a gradual, progressive trend through the Shungura sequence deposition. Rather, we observed a complex trend involving sudden changes. The mesowear angle analysis suggested that Elephas recki from the Shungura Formation had consistently grazing dietary habits throughout its evolution, except for some slight tendencies of mixed browse/graze diet in certain time intervals. We therefore did not observe any correlation between morphological change and feeding preferences over two million years. This delay between the acquisition of the observed diet and purportedly consequent morphological changes questions the classical interpretations of factors at play in this evolutionary sequence
Leak-Rate Through Carbon Brush Seals: Experimental Tests Versus Predictions From a Porous Medium Approach
No full textInternational audienceThis study presents a detailed comparative analysis between experimental leakage flow rates and numerical predictions for carbon brush seals with long bristles, utilizing a porous medium model approach. A series of tests were carried out on a static rig (without rotor rotation). The experimental setup allows tests under various interference conditions, revealing significant insights into the flow behavior through the brush seal. A numerical model based on the Darcy-Forchheimer equation is developed to interpret the complex flow dynamics within the brush seal, accounting for viscous, compressible and inertial effects. The study evaluates the impact of brush deformation and porosity on flow resistance, leveraging experimental data to refine the numerical model parameters. This investigation not only deepens the understanding of brush seal flow physics but also improves the predictive accuracy of the numerical model in simulating operational conditions
Impact of chronic low back pain on implicit motor imagery assessed by a new laterality judgment task
No full textInternational audienceIt is clear that implicit motor imagery (IMI) is impaired by chronic pain in peripheral regions (hand, feet), but unclear in axial regions (neck, shoulder, back). Previous IMI tasks displayed small-amplitude movements of axial regions, which limits person-centered IMI processes mobilization. This study aimed to assess the impact of chronic low back pain (CLBP) on IMI processes with a new task displaying large-amplitude whole-body movements mobilizing the lumbar spine. Twenty patients with CLBP and twenty age-matched controls performed a laterality judgment task on four distinct whole-body movements (trunk flexion, trunk rotation, capoeira, kickboxing). Participants viewed images from four different body viewpoints (back, left, right and front), randomly presented. Mixed ANOVAs were used to compare judgment accuracy and response times between groups and conditions. In participants with CLBP, response times were longer than in controls. The response times of participants with CLBP were also associated with DN4 scores, a self-reported questionnaire assessing neuropathic pain. We validated the use of a person-centered IMI because, for all participants, the accuracy decreased and the response times increased for images presented in the front viewpoint, i.e. when a 180° turn in IMI was required, compared to other viewpoints. The laterality judgment task proposed here confirmed that CLBP impacts IMI processes, and that the nature of pain (neuropathic or mechanical) needs to be considered because it seems to modulate IMI processes.PerspectivesA laterality judgment task with large-amplitude lumbar movements is key to show that CLBP alters processing speed of sensorimotor information originating from the painful region. This task could become an objective tool, transferable in clinical settings, for assessing the impact and the progression of CLBP on motor control processes