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Development of a health promoting sports clubs intervention: An intervention mapping process analysis
No full textInternational audienceDeveloping and implementing health promotion interventions in sports clubs is challenging. Implementing interventions in real world settings should be specific to a sports club's context, particularly their voluntary nature. The present study maps and analyzes the development of the PROSCeSS intervention, designed to support sports clubs to implement health promotion. A case study design mobilising Intervention Mappingneeds assessment, matrix of change, theory of action, program design, plan for adoption and implementation and evaluationdescribes the multi-phase intervention. Results encompass the main findings from i) a literature review and a concept mapping study as a needs assessment; ii) a Delphi study and health promoting sports club intervention framework to design the matrix of change; iii) a case study among sports clubs and sports federations to select the theory of action; iv) the intervention co-construction to create the program; v) results from a pilot study to validate the plan for adoption; and vi) implementation and presentation of the e-PROSCeSS questionnaire creation and hybrid type-3 protocol as an evaluation method. The discussion explores the tensions created between evidence driven strategies and the habits of sports clubs, the use of top-down versus bottom-up approaches and reflections on the recursive rather than linear process adopted by the authors.</div
Modulation of persistent inward currents in alpha motoneurons with joint angle depends on muscle length
No full textInternational audienceDuring voluntary movement, activity of alpha motoneurons is modulated to account for changes in muscle force-generating capacity induced by variations in muscle length. To date, research has primarily focused on the modulation of ionotropic inputs, while the role of another key contributor to alpha motoneuron activity, persistent inward currents (PICs), has been largely overlooked. In this human study involoving young male participants (n=19), high-density surface electromyography signals were recorded from the gastrocnemius medialis and soleus muscles at different ankle positions, and subsequently decomposed into motor unit spiking activity. Metrics extracted from these spiking activities were used to estimate the respective contributions of PICs, neuromodulation, and inhibition to alpha motoneurons activity. To differentiate the impact of muscle length from muscle tension, we compared voluntary contractions performed at both similar relative torque levels and similar absolute torque levels across different ankle positions. Our results revealed that PIC-induced prolongation of motor unit discharges was reduced at longer muscle lengths, accompanied by increased inhibition. This effect was consistent across both relative and absolute torque conditions, supporting the hypothesis that muscle length is the primary driver of PICs modulation with change of position. These findings suggest that PICs may serve as an additional mechanism – likely related to inhibitory inputs - to regulate alpha motoneuron activity, ensuring adaptation to changes in muscle length
Excursion sets: from geometry to estimation
No full textThis Chapter introduces the statistical analysis of random field excursion sets i.e., regions where a real-valued random field exceeds a certain threshold based on a class of geometric measures called the Lipschitz-Killing curvatures. These geometric features provide computationally efficient and interpretable descriptors, useful in many applications such as astrophysics, medical imaging and environmental sciences. For instance in dimension 2, one has three curvatures: the area of the excursion set, its half-perimeter and its Euler-Poincaré characteristic. The aim of this Chapter is to illustrate how these geometric features are efficient statistical tools for the study of underlying random fields (hypothesis tests, inference procedures, etc.). But it also aims to highlight the various difficulties linked to the nature of the observations, particularly with respect to the estimation of higher-order moments of these curvatures and the treatment of edge and discretization effects. Particular attention is given to Gaussian related fields for which computations are facilitated
The sound of silence
No full textThe world of the sea is not one of silence: sounds are abundant and enable oceanologists to identify the organisms that live there, to understand some of their behaviour and to give indications about the state of health of ecosystems
Le standard juridique, essai d'une théorie générale à l'épreuve du droit des contrats: Compte rendu de thèse soutenue en 2022, Université Côte d'Azur
No full textInternational audienceLe droit n'a pas toujours besoin de crier pour se faire entendre. Il lui arrive aussi de murmurer. Et dans ce murmure, il y a parfois plus d'efficacité, plus de subtilité, plus d'humanité. Le standard juridique fait partie de ces formes de normativité discrètes mais puissantes. Longtemps traité comme un parent pauvre du droit, relégué aux marges de la rigueur juridique, il est aujourd'hui au coeur d'une révolution silencieuse. Loin de n'être qu'un résidu de la normativité, le standard juridique mérite d'être reconnu pour ce qu'il est : une technique juridique riche et opératoire. Cet article présente les fondements d'une théorie générale du standard comme sousdirective référée, c'est-à-dire comme norme secondaire articulée à</div
MUFASA: A Continuous-Time Stochastic Framework for Realistic Fluorescence Microscopy Simulation
No full textWe present MUFASA (Multi-Protocol Unified Fluorescence-based Advanced Simulation Algorithm), a physically grounded, continuous-time simulator for super-resolution fluorescence microscopy. By modeling fluorophore dynamics using continuous-time Markov chains, MUFASA’simulation feature yields realistic photon emission behavior across both Single Molecule Localization Microscopy (SMLM) and fluorescence fluctuation-based (FF-SRM) protocols independently of frame duration and sampling. The framework supports both individual emitters and structure-level simulations, incorporating photophysical transitions, photobleaching, as well as camera properties. To quantitatively validate simulations with real data, we consider a novel validation metric based on the 1-Wasserstein distance between simulated and experimental photon-count distributions. Along with simulations, another functionality makes use of fluctuation data to estimate key photophysical parameters (e.g. molar extinction coefficient) and to predict optimal laser-power ranges. An intuitive Python-based graphical interface enables real-time parameter tuning, visualization, and TIFF export. Designed for biologists, physicists, microscopists and numerical imaging engineers, MUFASA offers a practical platform for experimental planning, hypothesis testing, and potentially the generation of realistic training data for data-driven microscopy methods across different modalities
Solving the Hubble tension with the VLTI
No full textInternational audienceOptical interferometry can provide a decisive contribution to the Hubble tension problem from spectro astrometric angular measures of Active Galactic Nuclei Broad Line Regions (AGN BLR) combined with linear measures on the same targets provided by Reverberation Mapping (RM). To achieve such a major breakthrough in cosmology three conditions must be met. First, we need enough targets allowing to combine these two methods. Second, we need the SM measurements to be accurate enough. Third we need improved BLR models with additional geometrical constraints allowing to remove the model fitting biases that appear when we combine only SA and RM measures. We analyze these three conditions, and we show that they can be met on the VLTI with its current baselines and with the GRAVITY+ upgrade if we can extend the VLTI toward shorter wavelength. The J and H band give access to a higher angular resolution and to strong emission lines at low or moderate redshifts compatible with RM campaigns in less than 2-3 years. The gain in resolution is sufficient on the VLTI as it is to complement the SA measures with Differential Visibility (DV) measures on a large sample of targets. We show that DV yields a decisive complement of geometric constraints that, unlike SA measures, are not degenerate with the BLR kinematics. They can validate AGN model constraints derived from mid IR observations in the L, M and N bands. Accessing multiple lines at once with different ionization potentials also provides constraints on the radial structure of the BLR. To access enough targets in the J and H bands to meet the first condition we need to be able to fringe track at least up to magnitude K~15. We also mention strong evidence that such a fringe tracking magnitude is well within reach at the VLTI under GRAVITY+ with a new generation fringe tracker
Theia: Faint objects in motion or the new astrometry frontier
No full textInternational audienceIn the context of the ESA M5 (medium mission) call we proposed a new satellite mission, Theia, based on relative astrometry and extreme precision to study the motion of very faint objects in the Universe. Theia is primarily designed to study the local dark matter properties, the existence of Earth-like exoplanets in our nearest star systems and the physics of compact objects. Furthermore, about 15 of the mission time was dedicated to an open observatory for the wider community to propose complementary science cases. With its unique metrology system and "point and stare" strategy, Theia's precision would have reached the sub micro-arcsecond level. This is about 1000 times better than ESA/Gaia's accuracy for the brightest objects and represents a factor 10-30 improvement for the faintest stars (depending on the exact observational program). In the version submitted to ESA, we proposed an optical (350-1000nm) on-axis TMA telescope. Due to ESA Technology readiness level, the camera's focal plane would have been made of CCD detectors but we anticipated an upgrade with CMOS detectors. Photometric measurements would have been performed during slew time and stabilisation phases needed for reaching the required astrometric precision
Should hydrodynamics be taken into account when calculating the growth rate of microalgae in a photobioreactor ?
No full textInternational audienceMicroalgae, as photosynthetic organisms, are cultivated in photobioreactors for various industrial applications. Light intensity, a critical factor influencing their growth rate, is inherently non-uniform within photobioreactors. In regions distant from the illuminated surface, microalgae experience photolimitation due to insufficient photon availability, hindering optimal activation of the photosynthetic machinery. Conversely, near the illuminated surface, excessive light intensity can damage key photosynthetic proteins, leading to photoinhibition. While mixing in photobioreactors does not alter the light gradient, it influences the light exposure history of cells through hydrodynamic advection. In this study, we employ Han's mechanistic model to describe the dynamics of photon harvesting and its consequences, including photoinhibition and photolimitation. First, we calculate the time-averaged growth rate for arbitrary continuous light signals, revealing how mixing impacts growth under the assumption of periodic light signals generated by hydrodynamics. Next, we address the computational challenge of estimating growth rates in photobioreactors using computational fluid dynamics (CFD), modeling a single-phase incompressible fluid. Finally, we analyze the case of a raceway pond, evaluating errors arising when growth rate is estimated without accounting for hydrodynamics. We demonstrate that the gain in growth is related to the cell movement along the light gradient. Our results show that in predominantly laminar hydrodynamic regimes, hydrodynamics has only a marginal effect on microalgal growth. Moreover, we show that the average productivity can be estimated based on a static approximation of the average growth rate taking into account the light distribution, with an error lower than 10%
Structural Evolution of the Coastal Landscape in Klaipėda Region, Lithuania: 125 Years of Political and Sociocultural Transformations
No full textInternational audienceThe coastal region of Klaipėda (Lithuania) has experienced major political, economic, social, and cultural transformations since the 20th century. Landscapes as evolving expressions of land use and land cover patterns offer a valuable lens to analyse these changes. This study examines the evolution of physical landscape structures across the pre-Soviet, Soviet, and post-Soviet periods, using historical maps and open-access geospatial data. An ontological approach, combined with morphological and configurational metrics, reveals four major and relatively persistent landscape structures: hydrological systems (sea, lagoon, rivers), forest cover, farming intensity (from extensive grassland use to intensive arable farming), and semi-natural environments. Their structural evolution reflects broader cultural factors, such as contrasting land use traditions between former Prussian and Russian territories. The study also highlights the impact of Soviet collectivisation, marked by irrigation networks, agricultural intensification, and forest expansion. The post-Soviet period is characterised by widespread farmland abandonment and fragmentation, revealing new spatial dynamics and challenges in land reappropriation. Landscape transformations are predominantly structured around agricultural dynamics. Although the analysis was limited by the incomplete availability of data for this specific land use class, the centrality of agriculture in shaping territorial organisation is evident and reinforces the strong rural identity associated with the landscape