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Exploring the Fabrication, Properties, and Morphology of Fluorine Substituted Hydroxyapatite Coatings
No full textInternational audienceHighlights▪ Atomic Force Microscopy (AFM) was used to analyze the surface topography of FHAp coatings and MG63 cell adhesion on FHAp coatings surface. ▪ FHAp coatings displayed uniform deposition with evenly distributed particle conglomerates. ▪ MG63 cells maintained normal morphology and adhered consistently to FHAp coatings over 72 hours. ▪ AFM imaging revealed a monolayer of well-aligned cells on FHAp coatings, suggesting good biocompatibility. ▪ FHAp coatings offer promising surfaces for MG63 cell adherence and proliferation.</div
Case study on thermal and flow analysis of a water mist on a pool fire in a ventilated engine compartment
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Rigidity of min-max minimal disks in -balls with non-negative Ricci curvature
No full textInternational audienceIn this paper we prove a rigidity statement for free boundary minimal surfaces produced via min-max methods. More precisely, we prove that for any Riemannian metric g on the -ball with non-negative Ricci curvature and , there exists a free boundary minimal disk of least area among all free boundary minimal disks in . Moreover, the area of any such equals to the width of , has index one, and the length of is bounded from above by . Furthermore, the length of equals to if and only if is isometric to the Euclidean unit ball. This is related to a rigidity result obtained by F.C. Marques and A. Neves in the closed case. The proof uses a rigidity statement concerning half-balls with non-negative Ricci curvature which is true in any dimension
Weaving zeolite into long-lived catalysts
No full textInternational audienceThe spatial distribution of aluminum in zeolites plays a crucial role in optimizing their catalytic performance. Existing strategies often rely on combinations of inorganic and organic structure-directing agents to guide crystal growth and aluminum incorporation.However, these methods typically result in zeolite crystals with an aluminum-rich surface, providing limited control over the spatial placement of aluminum within the crystal structure. In this study, we explore an alternative "weaving" strategy aimed at synthesizing zeolites with alternating Al-rich and Si-rich nanodomains within single crystals. This approach involves the physical blending of two separately aged, amorphous sols with contrasting Si/Al ratios, followed by freeze-drying and steamassisted crystallization of the resulting solid in vapor. Unlike conventional hydrothermal synthesis, which produces zeolites with Al-enriched crystal surfaces, this modularized assembly enables systematic modulation of aluminum distribution, resulting in zeolite crystals with comparable bulk and surface Si/Al ratios, an uncommon feature for high-silica zeolites. The resulting interwoven zeolites, with closely matched bulk and surface Si/Al ratios, exhibit nearly a twofold increase in catalytic lifetime in the methanol-to-hydrocarbons reaction compared to a reference zeolite with a similar bulk composition but significant surface aluminum enrichment, underscoring the significant impact of aluminum spatial distribution on catalytic stability
Effects of Dribbling Constraints on Sprint Acceleration Performance and the Force-Velocity Profile according to Playing Positions in Professional Soccer Players
No full textInternational audienceThis study aimed to investigate the impact of dribbling on sprint acceleration performance (sprint time) and the associated force-velocity (F-V) profile among professional soccer players across playing positions. Participants (N = 52) were categorized as central defenders (CDs), wide defenders (WDs), central midfielders (CMs), wide midfielders (WMs), and forwards (Fs). A field method based on split times measurements during 30-m sprint acceleration was used to calculate maximal theoretical force (F0) and velocity (V0), maximal power (Pmax) and the F-V slope during sprinting without the ball and while dribbling. Our study revealed a significant decline in sprint performance during dribbling. CDs and WDs exhibited higher losses in 5-m split time (T5; 19%) compared to Fs (13%) and WMs (14%). CMs displayed higher losses in 20-m split time (T20; 11%) compared to Fs (8%). Pmax and F0 significantly decreased when dribbling, with a higher decrease in Pmax experienced by CMs (33%) compared to Fs (24%) and WMs (25%). Similarly, a higher decrease was observed in F0 for CMs (29%) compared to Fs (20%) and WMs (20%). The determination coefficients between the loss in T5 and Pmax (r² = 0.54), F0 (r² = 0.62), and the loss in T20 and Pmax (r² = 0.75), F0 (r² = 0.23), and V0 (r² = 0.22) indicated substantial relationships between sprint performance decline and losses in the F-V profile. In conclusion, this study highlights how dribbling affects sprint performance and the F-V profile differently across soccer playing positions. Coaches can tailor training programs considering the constraints imposed by dribbling for effective players’ development
Le rêve dans la magie rituelle latine
No full textInternational audienceLa vision en rêve, associée à un rituel magique, est l’un des moyens dont on peut user pour communiquer et obtenir satisfaction des démons, des esprits ou des anges, ici dans le cadre d’une forme de magie divinatoire. Dans les "experimenta" de magie rituelle que l’on a conservés dans les manuscrits de la fin du Moyen Âge(sur lesquels nous allons centrer notre propos), la place du rêve n’est pas central, mais en trouve toutefois un certain nombre d'occurrences, liées en général, mais pas exclusivement, à la détermination de l’avenir. Nous procéderons ainsi à un tour d’horizon assez descriptif de quelques-unes de ces opérations magiques, avant de tirer quelques conclusions quant aux traits qui leur sont communs, entre préparation rituelle, dévotion chrétienne et procès d'incubation
Géographie et prévisions locales dans les prédictions astrologiques générales du XVe siècle
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Enfin je veux dire on va où quoi ? Étude des emplois de "je veux dire" à l'oral en micro-diachronie : de la reformulation à la focalisation expressive
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Représenter la parole : une dimension fondamentale de la linguistique
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