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Topology optimization of rectangular parallel plate heat exchanger unit
No full textInternational audienc
Exfoliated montmorillonite nanofillers role on the high performance and the permeability of polyamide nanofiltration membrane
No full textInternational audienc
Hereditarily frequently hypercyclic operators and disjoint frequent hypercyclicity
No full textInternational audienceWe introduce and study the notion of hereditary frequent hypercyclicity, which is a reinforcement of the well known concept of frequent hypercyclicity. This notion is useful for the study of the dynamical properties of direct sums of operators; in particular, a basic observation is that the direct sum of a hereditarily frequently hypercyclic operator with any frequently hypercyclic operator is frequently hypercyclic. Among other results, we show that operators satisfying the Frequent Hypercyclicity Criterion are hereditarily frequently hypercyclic, as well as a large class of operators whose unimodular eigenvectors are spanning with respect to the Lebesgue measure.On the other hand, we exhibit two frequently hypercyclic weighted shifts on whose direct sum is not -frequently hypercyclic (so that neither of them is hereditarily frequently hypercyclic), and we construct a -type operator on , 1\le p<\infty which is frequently hypercyclic but not hereditarily frequently hypercyclic. We also solve several problems concerning disjoint frequent hypercyclicity: we show that for every , any disjoint frequently hypercyclic -tuple of operators can be extended to a disjoint frequently hypercyclic -tuple as soon as the underlying space supports a hereditarily frequently hypercyclic operator; we construct a disjoint frequently hypercyclic pair which is not densely disjoint hypercyclic; and we show that the pair is disjoint frequently hypercyclic, where is the derivation operator acting on the space of entire functions and is the operator of translation by .Part of our results are in fact obtained in the general setting of Furstenberg families
Immobilization of Trametes versicolor laccase on LDH/alginate composite beads for improved textile dyes decolorization
No full textInternational audienceLaccase is an oxido-reductase known for its applications in biomass valorization (lignin depolymerization), in fine chemicals (building-blocks synthesis) or in environment (wastewater treatment). It works with molecular oxygen and produces water as its only by-product. However, its practical use remains limited due to the low stability and poor reusability of free laccase.To overcome these challenges, laccase from Trametes versicolor was immobilized onto layered double hydroxide and alginate composite beads by a glutaraldehyde cross-linker to create an easily separable and stable enzyme. Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD) and energy-dispersive X-ray spectroscopy (EDX) were used to characterize the as-synthesized composite beads (laccase@MgFe(LDH)/alginate). The activity of the immobilized laccase was measured with 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) model substrate. Here, the optimal conditions of laccase immobilization were explored and the effects of various conditions of immobilization, pH, storage stability and thermal resistance of the (laccase@MgFe(LDH)/alginate) were also studied. The results revealed that the optimal conditions for laccase immobilization were a concentration of glutaraldehyde of 2.5 %, an amount of laccase (0.5 U/mg) of 2 mg/mL, and an immobilization time of 6 h. The stability of (laccase@MgFe(LDH)/ alginate) was >70 % of its initial activity, even after 10 cycles.The study of dye decolorization showed up to 74 % of methylene blue (MB) and 69 % of Crystal violet (CV) degradation, suggesting the use of immobilized laccase on MgFe(LDH)/alginate composite beads as a promising and environmentally friendly tool for the degradation of environmental pollutants, in particular for the removal of textile dyes from wastewater.</div
Comparison between hybrid cardiac rehabilitation and center-based cardiac rehabilitation: a noninferiority randomized controlled trial.
No full textInternational audienceCardiac rehabilitation (CR) is a cornerstone of heart disease (HD) management, enhancing functional capacity and quality of life. Hybrid cardiac rehabilitation (hCR), combining supervised center-based sessions with synchronous, real-time telerehabilitation at home, offers an alternative to conventional CR to overcome logistical barriers such as facility limitations, distance, and pandemic-related disruptions. This randomized controlled trial evaluated the noninferiority of hCR compared to standard CR in improving functional capacity in patients with chronic heart disease, including those with stable coronary artery disease. Seventy-five participants were randomized into two groups: the CR group, with exclusively center-based sessions, and the hCR group, with synchronous tele-rehabilitation sessions at home complemented by center-based sessions. Functional capacity was assessed using cardiopulmonary exercise testing, the six-minute walk test, and the wall squat test. Both groups showed significant improvements in functional outcomes, including walking distance (six-minute walk test), strength capacity (wall squat test), and cardiopulmonary exercise testing performance (P < 0.001). The improvements in the hCR group were statistically noninferior to those in the CR group. These findings demonstrate that hCR provides an effective alternative to conventional CR while addressing practical challenges in access to care. The hCR protocol represents a viable solution for expanding rehabilitation options without compromising outcomes, particularly for patients facing logistical constraints or during emergencies such as pandemics
Barat et Haimet de Jean Bodel - Édition, traduction et notes d'après le ms. BnF 837
No full textÉdition, traduction et notes de Barat et Haimet de Bodel d'après le manuscrit BnF fr. 83
Towards a consensus on the development of the aquatic curricula analysis tool using an ecosystem approach: a delphi method
No full textInternational audiencePhysical inactivity and drowning are two of the leading causes of death worldwide. While participation in aquatic physical activity can help reduce these public health challenges, it is crucial to equip young people with key water skills through a well-designed aquatic curriculum to protect them from drowning and engage them in the long term in aquatic physical activities. This study reports on the development of a tool to analyse aquatic curricula for 6-to-12-year-olds in Europe, addressing both aquatic health issues. Methods: Using a three-round Delphi method, 101 participants from eight European countries - including experts in teaching, organising and researching aquatic education - were asked to rate the relevance of criteria conceptualised through Bronfenbrenner’s ecological model. Results: 115 criteria were retained and grouped into eight categories: (1) curriculum management, (2) drowning epidemiology, (3) timetable, (4) location and equipment, (5) staff, (6) content, (7) assessment and (8) learners. The strong consensus on most of the criteria suggests that promoting physical activity and water safety are compatible goals. Conclusion: A well-designed aquatic curriculum, rooted in each level of the ecological model and organised through a multisystemic approach, can successfully achieve both objectives. The findings provide valuable insights for the design of aquatic safety promotion policies, as well as guidance for educators and policy makers to improve teaching strategies to increase physical activity while preventing drowning accidents.Contexte : L'inactivité physique et les noyades comptent parmi les principales causes de mortalité dans le monde. Si la participation à des activités physiques aquatiques peut contribuer à réduire ces enjeux de santé publique, il est crucial d'équiper les jeunes de compétences clés liées à l'eau grâce à un programme aquatique bien conçu, afin de les protéger contre les noyades et de les engager à long terme dans des activités physiques aquatiques. Cette étude présente le développement d’un outil permettant d’analyser les programmes aquatiques destinés aux enfants de 6 à 12 ans en Europe, en abordant les deux problématiques de santé aquatique.Méthodes : En utilisant une méthode Delphi en trois tours, 101 participants issus de huit pays européens – comprenant des experts en enseignement, en organisation et en recherche sur l’éducation aquatique – ont été invités à évaluer la pertinence de critères conceptualisés à travers le modèle écologique de Bronfenbrenner.Résultats : 115 critères ont été retenus et regroupés en huit catégories : (1) gestion du programme, (2) épidémiologie des noyades, (3) emploi du temps, (4) lieux et équipements, (5) personnel, (6) contenu, (7) évaluation et (8) apprenants. Le fort consensus sur la plupart des critères suggère que la promotion de l’activité physique et la sécurité aquatique sont des objectifs compatibles.Conclusion : Un programme aquatique bien conçu, enraciné dans chaque niveau du modèle écologique et organisé selon une approche multisystémique, peut atteindre avec succès ces deux objectifs. Les résultats fournissent des perspectives précieuses pour la conception de politiques de promotion de la sécurité aquatique, ainsi que des orientations pour les éducateurs et les décideurs politiques afin d'améliorer les stratégies d'enseignement visant à augmenter l'activité physique tout en prévenant les accidents de noyade
Impact of polymer binders on the aggregation modes of two-pieces CSH composites
No full textInternational audienc
Antimicrobial and antioxidant properties of water-soluble lignin extracts obtained from ozonation of Miscanthus giganteus and Vitis vinifera in a pilot-scale reactor
No full textInternational audienceLignin is a potential source of polyphenols with different biological activities which might be affected by the extraction or isolation process. This study investigated the effect of ozonation on the bioactive properties of water-soluble lignin extracts from Miscanthus giganteus (grass-type biomass) and Vitis vinifera (wood-type biomass). Total polyphenolic content, antioxidant activities (ABTS, DPPH and β-carotene bleaching assays), and antimicrobial properties were evaluated. Although ozonation did not improve the antioxidant activity per gram of lignin extract with any of the methods employed, it significantly enhanced extraction of antioxidants. All lignin extracts displayed significant antioxidant potential, DPPH IC50 values ranging from 7.6 to 29.0 µg/mL and ABTS ranging 64.1-154.6 mg Trolox/g extract. Miscanthus lignin extracts achieved 70.6 % β-carotene bleaching inhibition, compared with 96.2 % inhibition by BHT. Miscanthus lignin extracts exhibited better yield and antioxidant activity compared with vine shoots, likely due to their lower molecular weight and higher content of phenolic monomers. Antibacterial analysis revealed that Miscanthus lignin extracts had superior activity against Staphylococcus aureus and Escherichia coli, which was enhanced by ozonation and linked to zeta potential and compositional aspects. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) for Miscanthus extracts were 3 mg/mL and 6 mg/mL, respectively. Miscanthus extracts from 160 min ozonation demonstrated better antifungal activity than vine shoots, particularly against Penicillium digitatum (MIC:12 mg/ mL) compared with Botrytis cinerea (MIC:25 mg/mL). The bioactive properties of water-soluble lignin extracts from ozonated Miscanthus open up new possibilities for their potential use in food and food packaging applications.</div
