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Flexoelectricity in conjugated polymers and biopolymers
No full textInternational audienceFlexoelectricity, an alternative effect of piezoelectricity that corresponds to the appearance of an electrical polarization induced by a deformation gradient, offers new prospects for the self-powering of sensors, particularly through the recovery of ambient energy [1]. Recent studies show that flexoelectric polarization in high permittivity oxides can reach levels comparable to those obtained by the piezoelectric effect. More recent studies on conjugated polymers, especially poly(3,4-ethylenedioxythiophene) : polystyrene sulfonate (PEDOT: PSS) ([2], [3]), have revealed much higher flexoelectric coefficients up to 1000 times higher than those of conventional and insulating polymers, opening up new prospects for the development of high-performance flexoelectric materials. Our study involves improving the flexoelectric properties of conjugated polymers, in particularly by studying the influence of the mass ratio of PSS to PEDOT (from 2.5 to 20) (Fig.1), or by evaluating the flexoelectric response in bio-based polymers for an eco-friendly approach while investigating the dielectric and chemical properties of each simple
L'Esport, un secteur d'activité émergent futur outil de développement local ?
No full texthttps://www.echosciences-paysdelaloire.fr/articles/l-esport-un-secteur-d-activite-emergent-futur-outil-de-developpement-localProposition d'une synthèse L'objectif de ce document est de synthétiquement présenter l'Esport, d'identifier les enjeux actuels autour de cet objet nouveau. Il s'agit donc d'un document ressource mobilisable par différents acteurs cherchant à s'acculturer à l'Esport pour mieux en saisir les contours et potentiellement s'emparer de l'Esport comme nouveau champ d'activité. Ce document est rédigé en lien avec une thèse de doctorat en Géographie en cours à l'Université d'Angers et co-financée par la région Pays de la Loire. Cette thèse propose d'interroger les lieux d'Esport et leurs impacts dans les territoires. Qu'est-ce que l'Esport ? Il est possible de trouver de nombreuses définitions du terme « Esport » (Freeman &</div
Diagnostic and epidemiological landscape of anaerobic bacteria in Europe, 2020–2023 (ANAEuROBE)
No full textInternational audienceIntroductionDespite being implicated in a wide spectrum of community- and healthcare-acquired infections, anaerobes have not yet been incorporated into systematic surveillance programs in Europe.MethodsWe conducted a multicentre retrospective observational study analysing all anaerobic strains isolated from blood cultures in 44 European Hospital Centres over a 4-y period (2020–2023). Diagnostic approach, epidemiology, and antimicrobial susceptibility according to EUCAST v. 15.0 were investigated.ResultsOur study included 14,527 anaerobes, most of which were Gram-positive (45%) or Gram-negative (40%) bacilli. MALDI-TOF coupled to mass spectrometry was the most widely used tool for species identification (98%). Antimicrobial susceptibility testing was performed in the vast majority of centres, using mostly gradient diffusion strip (77%) and disk diffusion (45%) methods according to EUCAST guidelines. The most prevalent species were Cutibacterium acnes (18.7%), Bacteroides fragilis (16.3%), Clostridium perfringens (5.3%), Bacteroides thetaiotaomicron (4.2%), Fusobacterium nucleatum (3.5%), and Parvimonas micra (3.4%). C. acnes showed high resistance to benzylpenicillin (18%), clindamycin (39%), and imipenem (19% and 13% by MIC methods and disk diffusion, respectively). B. fragilis showed high resistance to amoxicillin/clavulanate (24%), piperacillin/tazobactam (22% and 14% by MIC methods and disk diffusion, respectively), clindamycin (22% by both MIC methods and disk diffusion), meropenem (13%), and metronidazole (10%, only by disk diffusion). A similar resistance pattern was observed in B. thetaiotaomicron, Bacteroides ovatus, and Parabacteroides distasonis. C. perfringens showed high resistance to clindamycin (69% and 45% by MIC methods and disk diffusion, respectively), while benzylpenicillin and metronidazole maintained over 90% activity. F. nucleatum showed high resistance to benzylpenicillin (11%), while Fusobacterium necrophorum showed alarming rates of resistance to clindamycin (12%), meropenem (16%) and metronidazole (11%).ConclusionsThis study presented an up-to-date analysis of the diagnostics and epidemiology of anaerobic bacteria in Europe, providing insights for future comparative analyses and the development of antimicrobial diagnostic and management strategies, as well as the optimization of current antibiotic treatments
L’événement, un Ba au service des communautés de fans : espace de création et de partage de connaissances
No full textInternational audienceCet article analyse le rôle des événements dans les écosystèmes de connaissances en mobilisant le concept de Ba et les travaux sur les Field Configuring Events. A travers une étude de cas unique (Angers Geekfest), nous expliquerons comment un événement, à travers la combinaison d’espaces physiques et virtuels favorise la création et l’échange de connaissances au sein de communautés de fans.Cet article analyse le rôle des événements dans les écosystèmes de connaissances en mobilisant le concept de Ba et les travaux sur les Field Configuring Events. A travers une étude de cas unique (Angers Geekfest), nous expliquerons comment un événement, à travers la combinaison d'espaces physiques et virtuels favorise la création et l'échange de connaissances au sein de communautés de fans. Mots clés : Communautés de fans, cyber Ba, événement, Field Configuring Events, connaissances Conférence AGESCO 2025 : Session 4 : Ecosystèmes de connaissances et technologies : opportunités et limites L'événement, un Ba au service des communautés de fans : espace de création et de partage des connaissances Cet article analyse le rôle des événements dans les écosystèmes de connaissances en mobilisant le concept de Ba et les travaux sur les Field Configuring Events. A travers une étude de cas unique (Angers Geekfest), nous expliquerons comment un événement, à travers la combinaison d'espaces physiques et virtuels favorise la création et l'échange de connaissances au sein de communautés de fans.</div
Les spécificités culturelles dans la recherche sur le haut potentiel intellectuel
No full textInternational audienc
The Quantum-Efficiency Normalized Light Scattering Spectra of Colloidal Nanoparticles in Solution: Quantitative Comparison between Theory and Experiment
No full textInternational audienceLight scattering is an intrinsic property of colloidal nanoparticles and molecular assemblies in fluid or solid transparent media. Various measurable light scattering parameters may contribute to the characterization of colloidal systems. Herein, a quantitative, spectrallyresolved, steady-state light scattering technique is formulated and realized for the characterization of ensembles of colloidal nanoparticles in solution: quantum-efficiency normalized light scattering (QENLS) spectroscopy. QENLS spectra are complementary to standard ultraviolet-visible-near-infrared (UV-vis-NIR extinction spectra. Their measurement does not require knowledge of nanoparticle concentration, and they can be quantitatively compared to theoretical calculations. This is illustrated for archetypal plasmonic gold nanospheres, nanocubes and nanorods. We find good agreement between experimental and theoretical QENLS spectra for gold nanospheres and nanocubes, corroborated by results from the literature. Concerning gold nanorods, our QENLS results fall into the broad, somewhat disperse trends reported in the literature
Are Botrytis cinerea small RNAs a real threat for grapevine?
No full textInternational audienceWhile Botrytis cinerea is notorious for having a broad host range, population studies revealed that this species includes multiple co-existing populations that show a certain degree of host specialization. Genome sequencing of strains representing French populations isolated from tomato (Solanum lycopersicum) or grapevine (Vitis vinifera) was previously conducted to investigate the genomic correlates of host-specialization. This revealed that the main grapevine-associated population of B. cinerea harbors two specific retrotransposons i.e. Copia 4 and Gypsy 7. Interestingly, these retrotransposons generate small RNAs (sRNAs) with structures similar to the previously published B. cinerea effectors that highjack the Arabidopsis thaliana and S. lycopersicum AGO proteins to manipulate the host immunity.The role of the Copia 4- and Gypsy 7-derived sRNAs in the interaction between B. cinerea and grapevine was therefore investigated using the representative strain Vv3 isolated from grapevine (https://bioinfo.bioger.inrae.fr/portal/genome-portal/, ANR grant 20‐PCPA‐0010 VITAE). Unfortunately, immunoprecipitation of the V. vinifera AGO to identify the loaded fungal sRNA was not possible due to the lack of an efficient antibody. Nevertheless, grapevine genes potentially targeted by the Vv3 sRNA were predicted by in silico analysis and by RNAseq of infected berries. We then used RLM-RACE to try to validate the predicted cutting site of the mRNA of these V. vinifera genes. In parallel, we investigated the role of the B. cinerea Dicer proteins Dcl1 and Dcl2 in the generation of the Copia 4- and Gypsy 7-derived small RNAs, and in the virulence toward grapevine. Single and double KO mutants (dcl1, dcl2, dcl1dcl2) were generated in the Vv3 strain. The resulting impaired production of small RNAs by these mutants was assessed by stem-loop RT-PCR. Finally, pathotests on berries and leaves were conducted with the dcl mutants and the results cast doubt on a significant role for small RNAs on the B. cinerea / V. vinifera interaction
Syndactyly release with full-thickness skin graft harvested from the wrist: About 24 webspaces
No full textInternational audienceThe management of congenital syndactylies often requires the use of a full-thickness skin graft to reconstruct the affected web space. Traditionally, full-thickness skin grafts are harvested from the groin region, but using the anterior aspect of the wrist may offers benefits in terms of scar quality while simplifying surgical time. This descriptive study evaluates scar quality (at donor and recipient site) associated with full-thickness skin graft harvested from the volar wrist in syndactyly release. We conducted a retrospective single-center study including patients who underwent syndactyly release with full-thickness skin graft harvested from the anterior wrist. Scar assessment was performed using the Observer Scar Assesment Scale, the Vancouver Scar Scale and the Withey Score. Overall, our results show high scores for scars at both donor and recipient sites. In conclusion, harvesting full-thickness skin graft from the volar wrist in syndactyly release is a simple and effective option for covering defects on the digits, while producing high-quality scars
Aborder la confidentialité des données et l'interconnectivité dans les jumeaux numériques : une étude de cas sur le cycle d'eau chaude d'un banc d'essai de pompe à chaleur
No full textContext: The concept of Industry 4.0 is increasingly significant in today's industrial landscape. There are numerous emerging technologies associated with Industry 4.0, including Digital Twin (DT). However, the adoption of DT faces several research challenges that hinder its seamless integration into industrial environments. These challenges include ensuring the security of data exchanged and improving the interconnectivity among industrial assets within DT systems. Tackling these issues is crucial to enhance the benefits of DT in the context of Industry 4.0. Objective: This paper proposes and evaluates a DT prototype that ensures encryption of data at rest and in transit during transmission over the Internet. Additionally, the design of this prototype facilitates signal exchange between heterogeneous physical equipment and software. Method: Established on the Six-Step DT Design Framework outlined in the literature and aligned with the International Organization for Standardization (ISO) on DT, this paper presents, a Digital Twin prototype of the heat pump test bench's hot water cycle (DT-HP-HWPrototype) using the Node-RED platform as a case study. Results: This study introduces a novel deployment diagram of a data-driven DT hosted on a remote cloud server accessible regardless of the DT Users'Contexte : Le concept d’Industrie 4.0 prend une importance croissante dans le paysage industriel actuel. De nombreuses technologies émergentes y sont associées, dont le jumeau numérique (JN). Cependant, l’adoption du JN se heurte à plusieurs défis de recherche qui entravent son intégration transparente dans les environnements industriels. Ces défis incluent la sécurité des données échangées et l’amélioration de l’interconnectivité entre les actifs industriels au sein des systèmes JN. La résolution de ces problèmes est cruciale pour optimiser les avantages du JN dans le contexte de l’Industrie 4.0.Objectif : Cet article propose et évalue un prototype JN qui assure le chiffrement des données au repos et en transit lors de leur transmission sur Internet. De plus, la conception de ce prototype facilite l’échange de signaux entre des équipements physiques et logiciels hétérogènes.Méthode : Établi selon le cadre de conception JN en six étapes décrit dans la littérature et conforme aux normes de l’Organisation internationale de normalisation (ISO) sur le JN, cet article présente un prototype JN du cycle d’eau chaude sanitaire du banc d’essai de pompe à chaleur (Prototype JN-HP-HW) en utilisant la plateforme Node-RED comme étude de cas.Résultats : Cette étude présente un nouveau schéma de déploiement d'une DT pilotée par les données, hébergée sur un serveur cloud distant, accessible quel que soit l'emplacement des utilisateurs. Le temps aller-retour moyen mesuré est de 851 ms pour l'envoi des commandes de contrôle de la DT sur un réseau Internet 4G.Conclusion : L'étude de cas souligne qu'une DT temps réel souple peut être efficacement mise en œuvre, notamment pour la surveillance des actifs industriels, tout en préservant la confidentialité des données. Néanmoins, des recherches supplémentaires sont nécessaires pour définir les besoins en réseaux informatiques du composant DT et pour améliorer la granularité de la représentation des processus industriels au sein du prototype DT-HP-HW
