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"De Marc Batta...à Clément Turpin". Les arbitres de football en France, du semi-professionnalisme au professionnalisme
No full textInternational audienceThe aim of this article is to understand how the elite of French referees reached, from the second half of the 1990s until today, the status of professional. Many archival materials are used in this study : institutional archives, gathered information from interviews with former referees, member of the refereeing administration and also of the trade union of football referees (SAFE). These archives allow us to examine the modifications made to the refereeing structure with regard to the European stage (UEFA) and the international stage (FIFA), and, on the other hand, to analyse the careers and characteristics of elite referees, taking into account the progressive arrival of technological innovations (Autoreference). If it is a question of studying what is concretely modified on the field for a first-rate referee, particularly from a technical and athletic point of view, it is therefore appropriate to analyse all the side effects of the ultra-modern elite referee’s life, which is punctuated by training, travel and meetings. This professionalisation began at the end of the 1990s under the leadership of Michel Vautrot and even more in the early 2000s, with the creation of the « DTNA », CTRA positions, and the creation of assistant and feminine sections. From 2006, the creation of SAFE allows elite referees to negotiate new conditions of practice, in connection with the Lamour law which provides a new status to referees. Since 2016, some leading referees have become employees of the French Football Federation. They no longer have to take on a profession alongside being a referee and can thus be considered professionnals referees. They then become similar to their colleagues from across the Channel, full-time referees since 2001 (Webb, 2019). Finally, this article is about studying the differences and developments between a referee such as Marc Batta, a semi-professional referee in the mid-1990s and Clément Turpin, currently a professional referee.L’objet de cet article est de comprendre comment les arbitres d’élite français sont passés, du milieu des années 1990 à aujourd’hui, d’un statut semi-professionnel à celui de professionnel. Plusieurs sources sont utilisées dans ce cadre : telles que des archives institutionnelles, des entretiens avec des arbitres et membres de la structure de l’arbitrage, mais aussi du Syndicat des Arbitres de Football d’Élite (SAFE). Ces dernières nous permettent d’étudier la modification de la structure arbitrale, des carrières des arbitres et de l’exercice de l’arbitrage, en lien avec l’arrivée d’innovations technologiques (Autoréférence), faisant tous partie de cette professionnalisation des arbitres d’élite. S’il s’agit d’étudier ce qui est modifié concrètement sur le terrain pour un arbitre de premier plan, notamment d’un point de vue technique et athlétique, il convient ainsi d’analyser tous les à-côtés de la vie de l’arbitre d’élite ultra-moderne, qui est rythmée par des formations, des entraînements physiques, des déplacements et des rencontres toujours aussi nombreuses. Cette professionnalisation s’amorce à la fin des années 1990 sous la houlette de Michel Vautrot et encore plus au début des années 2000, avec la création d’une Direction Technique Nationale de l’Arbitrage, de postes de CTRA et des filières « assistant » et « féminine ». À partir de 2006, la création du SAFE permet aux arbitres d’élite de négocier de nouvelles conditions d’exercice, en lien avec la loi Lamour qui fournit un nouveau statut aux arbitres. Depuis 2016, certains arbitres de premier plan deviennent des salariés de la Fédération Française de Football (FFF). Ils n’ont plus à assumer une profession en parallèle de leur activité arbitrale et peuvent être ainsi considérés comme des professionnels de l’arbitrage. Ils deviennent alors semblables à leurs collègues d’Outre-Manche, arbitres à temps plein depuis 2001 (Webb, 2019). Finalement, il s’agit d’étudier les différences et les évolutions entre un arbitre tel que Marc Batta, arbitre semi-professionnel au milieu des années 1990 et Clément Turpin, actuellement un professionnel de l’arbitrage
The ‘Écolo’coteaux’ programme: an outdoor and cycling school-based intervention on daily physical activities opportunities
No full textInternational audienceBackground: Despite well-documented health benefits, children's engagement in Physical Activity (PA) remains insufficient, particularly in disadvantaged areas. Schools provide structured opportunities for PA, yet interventions often fail to increase overall moderate-to-vigorous physical activity (MVPA). Recent approaches suggest that focusing on physical activity opportunities (contexts where movement is encouraged) rather than overall volume may yield better results. The Écolo'coteaux programme aimed to explore whether an outdoor and cycling-based intervention could enhance PA engagement by reshaping daily physical activity opportunities. While outdoor education and cycling interventions have independently demonstrated benefits, their combined effects remain unexplored. Methods: A total of 96 children were assigned to either an intervention or control group. The intervention group participated in an outdoor and cycling education programme (4h/week, October to June), while the control group followed the standard physical education curriculum. PA levels were measured using accelerometers, and daily diaries were used to track PA opportunities. After applying exclusion criteria, 28 children (intervention: n = 10; control: n = 18) were included in the analysis. A two-way repeated-measures ANOVA and Kruskal-Wallis post-hoc tests assessed changes in MVPA and sedentary behaviour (SB) across PA opportunities. Results: No significant effect of the intervention on overall SB and MVPA was observed. However, PA patterns were significantly reorganized: the intervention group showed increased MVPA during physical education lessons (+13%) and active transport to school (+6%), while the control group experienced a decline in MVPA during weekend afternoons (-3%) alongside an increase in SB (+7%). Conclusion: Rather than increasing overall physical activity levels, the intervention influenced the redistribution of physical activity
Enhancing Query Efficiency for D-DNNF Representations Through Preprocessing
No full textInternational audienceIn this paper, we investigate preprocessing techniques aimed at improving the efficiency of accessing models of propositional formulas represented in conjunctive normal form (CNF). We focus on three fundamental tasks: uniform sampling, direct model access, and model enumeration. Our analysis reveals that most state-of-the-art preprocessors, when they do not preserve formula equivalence, are generally unsuitable for these tasks. In contrast, we demonstrate that preprocessors which preserve model counts can be effectively leveraged, provided relevant preprocessing information is maintained. To validate our approach, we perform extensive experiments on a diverse suite of benchmarks from multiple domains. The experimental results show that our preprocessing methods are both efficient and robust, yielding significant performance improvements for model access queries when CNF formulas are compiled into d-DNNF representations.</div
Large reversible magnetocaloric effect in GdPO4 nano-spherical particles at ultralow temperatures
No full textInternational audienceThis study reports the synthesis of gadolinium phosphate (GdPO4) with a monoclinic crystal structure (P21/n) using a high-temperature solid-state reaction method. Rietveld refinement of the X-ray diffraction (XRD) data revealed lattice constants of a = 0.66497(5) nm, b = 0.68457(5) nm, and c = 0.63327(4) nm. The magnetic and magnetocaloric properties of GdPO4 were investigated in detail. The ferromagnetic (FM) to paramagnetic (PM) phase transition temperature was determined to be around 1.8 K. The transition was strongly supported by Arrott plots and a universal phenomenological curve describing the magnetocaloric effect (MCE). GdPO4 exhibits significant magnetic entropy changes (−ΔSM). The maximum values of −ΔSmaxM are 20.43 J/(kg·K) and 44.79 J/(kg·K) for a magnetic field change (μ0ΔH) of 2 T and 9 T, respectively. Our analysis indicates that the GdPO4 nano-spherical particles exhibit short-range magnetic ordering, characterized by the coexistence of ferromagnetic (FM) and antiferromagnetic (AFM) interactions
Homonuclear decoupled INADEQUATE NMR methods with improved sensitivity and resolution in solid-state NMR.
No full textInternational audienceThe two-dimensional (2D) refocused INADEQUATE NMR experiment, which correlates double-quantum (DQ) and single-quantum (SQ) coherences, is widely used to probe the chemical connectivities in solids. Nevertheless, the multiplets along the F2 dimension reduce the resolution and sensitivity of this experiment. The Composite-Refocusing (CR) technique with two excitation pulses has been proposed to suppress these multiplets in 2D INADEQUATE spectra of liquids. Recently (Kolyagin et al., J. Phys. Chem. Lett., 13 (2022) 10793), we showed that this technique can also be applied to suppress doublets in 2D 29Si INADEQUATE spectra of 29Si-enriched zeolites, which resulted in improved sensitivity and resolution. We investigate here how this INADEQUATE-CR scheme can also be applied for two other spin-1/2 isotopes: 13C and 31P. We also demonstrate the possibility to accelerate the acquisition of these 2D INADEQUATE-CR spectra with a very simple bi-exponential non-uniform sampling (NUS). For instance, in the case of 31P nuclei in SnP2O7, the use of the INADEQUATE-CR method with NUS yields a 7.5-fold reduction in experimental time with a simultaneous 1.4–1.5 gain in resolution with respect to a conventional INADEQUATE acquisition. Furthermore, we analyze the origins of the possible artifacts in these 2D spectra, including mismatching between J-coupling constants and refocusing delays, differences in relaxation times, coupling with a proton bath, and spin systems containing multiple identical nuclei. Based on this analysis, we introduce a new z-filtered INADEQUATE-CR version, which produces artifact-free 2D spectra, even in the presence of several distinct J-couplings and relaxation times or for multi-spin systems, and notably samples with high proton density
Le graphe des capacités : Une granularité fine pour accompagner chaque étudiant dans sa Zone de Développement le plus Proche
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Hydrohydroxymethylation of a bio-based substrate catalyzed by rhodium in a recyclable biphasic system using ionic liquids
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Reductive Hydroformylation of Vegetable Oils Derivatives Catalyzed by a Rhodium/Trialkylamine Combination Associated to Oxide Materials: A New Step Towards a Simple, Robust and Recyclable Catalytic System
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High-Performance Natural Dye-Sensitized Solar Cells Employing a New Semiconductor: Gd2Ru2O7 Pyrochlore Oxide
No full textInternational audienceWe investigated a novel natural dye-sensitized solar cell (DSSC) utilizing gadolinium ruthenate pyrochlore oxide Gd2Ru2O7 (GRO) as a photoanode and compared its performance to the TiO2-Gd2Ru2O7 (TGRO) combined-layer configuration. The films were fabricated using the spin-coating technique, resulting in spherical grains with an estimated mean diameter of 0.2 µm, as observed via scanning electron microscopy (SEM). This innovative photoactive gadolinium ruthenate pyrochlore oxide demonstrated strong absorption in the visible range and excellent dye adhesion after just one hour of exposure to natural dye. X-ray diffraction confirmed the presence of the pyrochlore phase, where Raman spectroscopy identified various vibration modes characteristic of the pyrochlore structure. Incorporating Gd2Ru2O7 as the photoanode significantly enhanced the overall efficiency of the DSSCs. The device configuration FTO/compact-layer/Gd2Ru2O7/Hibiscus-sabdariffa/electrolyte(I−/I3−)/Pt achieved a high efficiency of 9.65%, an open-circuit voltage (Voc) of approximately 3.82 V, and a current density of 4.35 mA/cm2 for an active surface area of 0.38 cm2. A mesoporous TiO2-based DSSC was fabricated under the same conditions for comparison. Using impedance spectroscopy and cyclic voltammetry measurements, we provided evidence of the mechanism of conductivity and the charge carrier’s contribution or defect contributions in the DSSC cells to explain the obtained Voc value. Through cyclic voltammetry measurements, we highlight the redox activities of hibiscus dye and electrolyte (I−/I3−), which confirmed electrochemical processes in addition to a photovoltaic response. The high and unusual obtained Voc value was also attributed to the presence in the photoanode of active dipoles, the layer thickness, dye concentration, and the nature of the electrolyte
Synthesis, characterization and biological screening of N-heterocyclic carbene Ag(I) catalysts for aldehyde-amine-alkyne coupling reaction.
No full textInternational audienceN-heterocyclic carbenes (NHCs) are widely recognized for their applications in organometallic chemistry, catalysis, and pharmaceutical research due to their unique steric and electronic properties. In this study, we report the synthesis of six novel unsymmetrical N,N-disubstituted benzimidazolium salts (2a-f) and their corresponding silver-NHC complexes (3a-f). The structures of all compounds were characterized using nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FT-IR), and elemental analysis. The biological potential of these compounds was evaluated through in vitro antimicrobial assays against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Candida glabrata. Additionally, anticancer activity was tested against A549, HCT116, and BEAS-2B cell lines, revealing promising results for some derivatives. Preliminary catalytic studies demonstrated the effectiveness of the silver-NHC complexes in A3-coupling reactions involving aldehydes, alkynes, and amines. These reactions yielded propargylamines with high conversion rates (up to 90%) using minimal catalyst amounts. This work highlights the dual utility of these compounds as both potent biological agents and efficient catalysts, paving the way for further exploration of their applications in medicinal chemistry and sustainable catalysis