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Traitement du burnout professionnel et des symptômes d'insomnie chez les adultes : une revue systématique des interventions
No full textMethod for the systematic reviewPROSPERO ProtocolProtocole PROSPER
Gesture Use and Interactional Dynamics in L2 Speakers: A Comparative Study of Face-to-Face and Online Interactions
No full textInternational audienceStudies in second language (L2) interaction have shown that gestures enhance understanding,help manage turn-taking, address lexical gaps and collaboratively construct meaning during interactions(Gullberg, 2006; Huang et al., 2019; Mori & Hayashi, 2006; Yin, 2021, among others). This study investigates the differences in gesture use between face-to-face (F2F) and online interactions among Cantonese L2 speakers of English, focusing on how these gestures may influence interactional dynamics.The increasing transition to online platforms in educational settings compels us to examine its possibleeffect on gesture use by L2 learners. Previous research indicates that while online interactions may reducedistractions and communicative pressure, they also limit the visibility and effectiveness of gestures (Hampel & Stickler, 2012). Our study compares nineteen independent pairs of Cantonese L2 English speakers (average age 21) —ten engaging in online discussions and nine participating in F2F conversations. All pairs were instructed to sit in the same position to be able to record their whole bodies. Participants were asked to discuss and prioritize factors affecting well-being, allowing us to compare the same topics of discussion across the two conditions. We analyzed gesture types, turn-taking mechanisms and head and body movements.Preliminary findings on gesture type reveal that L2 learners produce more referential gestures in F2Finteractions compared to their online counterparts. Despite similar overall frequencies of other gesturetypes, qualitative analyses show how the F2F context fosters greater alignment as learners are more likelyto adapt and repeat their interlocutor's gestures. In contrast, online interactions exhibited longer turns with fewer interruptions, suggesting a more “polite” turn-taking dynamic but potentially less visible engagement.This research highlights the importance of context in L2 multimodal communication and the need to account for differences in gesture behavior to inform teaching practices and enhance learner experiences in both physical and virtual environments
The effect of the mineral matrix during thermal analysis of polymers: Implications for microplastics characterization
No full text(IF 6.2;Q1)International audienceThe exponential growth of global plastic production complicates waste management, leading to the accumulation of microplastics in the environment. Currently, the identification and quantification of microplastics rely on various analytical methods that often require sample pretreatments, which can introduce errors.The Rock-Eval® thermal method, through the total quantity of hydrocarbon (Total HC parameter) and the temperature of their maximum release (Tpeak), identifies and quantifies polymers when individually analyzed. However, mineral matrices in natural sediments can influence these parameters. In this study, synthetic mixtures of various mineral matrices and polymers were analyzed using the thermal Rock-Eval® method.Three effects of mineral matrices on the thermal degradation of polymers have been identified: (1) catalysis, which accelerates the polymer degradation;(2) multimodal inhibition, characterized by a fractionated release of hydrocarbons, first at expected pyrolysis temperatures and then at higher temperatures; and (3) retention, which reduces total HC released. The same mineral matrix can produce different effects depending on the type of polymer with which it is mixed. For instance, illite catalyzes the degradation of polyethylene (PE), but inhibits that of polyethylene terephthalate (PET).Despite these effects, linear regressions between the Total HC and polymer content in synthetic mixtures provide a coefficient of determination (r²) of 0.99, confirming that matrix effects do not hinder polymer quantification. Furthermore, mixtures with natural matrices show effects comparable to those observed with synthetic matrices.These findings represent a first step towards understanding the effects of the matrix and confirm the possibility of using the thermal Rock-Eval® method as a simple tool to identify and quantify microplastic pollution in natural sediments
Le travail des frontières dans les dynamiques institutionnelles. Etude historique du champ du handicap entre 1977 et 2022
No full textThe concept of the boundary is omnipresent in the literature on organizations, yet it has been little conceptualized. This study seeks to enrich knowledge of this notion by integrating it into the neo-institutional theory research program. In so doing, we focus on the different types of boundary work, associated resources and their influence on institutional dynamics in the field of disability in France. To this end, our research is based on 53 semi-structured interviews with current and former Agefiph employees, Agefiph stakeholders and disability referents in private-sector companies, 600 documents from primary and secondary sources, and a field notebook from four years of ethnography. By mobilizing the literature on institutional work, boundary work and institutional biography, the study shows that the relational and discursive characters of boundary work favor the construction of the boundaries of an emerging profession and the stakeholders' areas of competence. The study also shows that configurational actors play an important role in the organization of a field. It highlights the need to align an organization's internal and external legitimacies to maintain the organization. Finally, it shows that actors arriving from a new field bring with them new institutions from their field of origin, institutions that may impose themselves or be absorbed by existing institutional infrastructures.Le concept de frontière est omniprésent dans la littérature sur les organisations, pour autant in n’est que très peu conceptualisé. Cette étude cherche à enrichir les connaissances sur cette notion en l’intégrant dans le programme de recherche en théorie néo institutionnelle. Ce faisant, nous nous intéressons aux différents types de travail des frontières, aux ressources associées et leurs influences sur les dynamiques institutionnelles du champ du handicap en France. Pour cela, notre recherche s’appuie sur 53 entretiens semi-directifs menés auprès d’employés actuels et anciens de l’Agefiph, des parties prenantes de cette dernière et de référents handicap dans des entreprises du secteur privé, 600 documents issus de sources primaires et secondaires et d’un carnet de terrain de quatre années d’ethnographie. En mobilisant la littérature sur le travail institutionnel, le travail des frontières et la biographie institutionnelle, l’étude montre que les caractères relationnel et discursif du travail des frontières favorisent la construction des limites d’une profession émergente et des domaines de compétences des parties prenantes. L’étude montre également que des acteurs configurationnels jouent un rôle important dans l’organisation d’un champ. Elle souligne la nécessité d’aligner les légitimités internes et externes d’une organisation pour maintenir l’organisation. Enfin, elle montre que les acteurs qui arrivent d’un nouveau champ apportent avec eux de nouvelles institutions issues de leur champ d’origine, institutions qui peuvent s’imposer ou être absorbées par les infrastructures institutionnelles en place
INSIGHTS INTO ROCK GLACIER ORIGINS AND DYNAMICS: GEOMORPHOLOGICALMAPPING OF THE EASTERN CAJÓN DE PINCHEIRA GLACIER-PERIGLACIAL COMPLEX (34°S)
No full textInternational audienc
Promising Alloys for Hydrogen Storage in the Compositional Space of (TiVNb) 100– x (Cr,Mo) x High-Entropy Alloys
No full textInternational audienceThis study reports on the search for the most promising alloys in the compositional space of (TiVNb)80Cr20-xMox (x = 5, 10 and 15) and (TiVNb)75Cr25-xMox (x = 5, 10, 15 and 20) high entropy alloys. Firstly, data-driven machine learning applied on these systems predicts that increasing Mo content destabilizes the enthalpy of the hydride phases. Second, experimental and density functional theory (DFT) validations were performed. The as-prepared alloys have single-phase bcc lattices and rapidly absorb hydrogen to form fcc-type hydrides with a high capacity between 1.6 and 2.0 H/M. Despite a positive effect on the thermodynamics of the hydride phases, increasing the Mo content in these alloys has a negative effect on the maximum capacity. The cycling experiments highlight the need to balance the reversible capacity, cycle life, and crystalline stabilities of these phases. Therefore, considering all these results, the most promising alloy with trade-off properties within the targeted compositional space has been identified to be (TiVNb)75Cr5Mo20 that shows a maximum capacity of 2.6 wt. % (1.8 H/M), a reasonable enthalpy of hydride formation (-38.6 kJ/mol H2), and a notable gravimetric reversible capacity of 1.42 wt.% at room temperature. To identify the most promising high entropy alloys for this application, integrated machine learning predictions followed by experimental and DFT validations proved to be an effective strategy
New analysis of the ν5 and ν6 interacting bands of Trans-HONO and of the ν6 band of Cis-HONO by high-resolution Fourier-transform spectroscopy in the 13-25 µm region.
No full textInternational audienceThis article is part of our series of papers involving the reinvestigations of several fundamental bands of the Trans-HONO and Cis-HONO conformers of nitrous acid (HONO). The present work deals with the 13-25 µm region which was already investigated in 2007 [A. Perrin, S. Miljanic, A. Dehayem-Kamadjeu, P. Chélin, J. Orphal, J. Demaison, Journal of Molecular Spectroscopy 245 (2007) 100-108] at lower resolution. This HONO absorption band can potentially contribute to the observed infrared signature of the future “Far infrared Outgoing Radiation Understanding and Monitoring” (FORUM) satellite instrument (https://www.forum-ee9.eu/). Using high-resolution Fourier transform spectra recorded at the SOLEIL synchrotron, we performed a new and more extended investigation of the ν5 (ONO bend) and ν6 (torsion) interacting fundamental bands of Trans-HONO located near 595.620895 and 543.880143 cm–1, respectively, and of the ν6 band of Cis-HONO located at 639.742715 cm–1. As during our previous investigation, the A- and B-type Coriolis interactions coupling the 51 and 61 energy levels were considered for both conformers. In addition, for Cis-HONO the B-type Coriolis resonance coupling the 61 energy levels with those of the 41 state located at 851.942928 cm-1 was also accounted for [W. Tchana Betnga, A. Perrin, L. Manceron, J. Vander Auwera, F. Hindle, A. Cuisset, G. Mouret, R. Bocquet, P. Roy, X. Landsheere, A. Voute, F. Kwabia Tchana. JQSRT 325 (2024) 109082]. Finally, absolute line intensities were obtained for the ν5 and ν6 bands of both conformers by careful comparison of line intensities at 13-25 µm against those at 11 µm. For this computation, the more precise value ΔE(Cis-Trans) = 95.8 ± 9.2 cm-1, determined recently, was used for the HONO Cis- to Trans- conformers energy difference
Improved synthesis method and thermoelectric properties of the YbCuSb Zintl phase
No full textInternational audienceYbCuSb was synthesized via an improved quasi solid-state synthesis method for this compound, using either an open carbon crucible or a sealed stainless steel crucible. The former crucible led to a total fraction of secondary phases of 25 % whereas the latter one led to less than 2% of secondary phases. Densification was performed by spark plasma sintering to reach relative density values larger than 94 %. These densified YbCuSb samples are air-and water-stable at room temperature. Combined electronic transport measurements and ab initio electronic structure calculations led to the conclusion that YbCuSb is a semiconductor and can be classified as a Zintl compound. The present samples showed p-type conduction with large values of electronic mobility (78 cm 2 V -1 s -1 at 300 K) and small density of states effective mass (0.4 m0, with m0 the bare electron mass). They also displayed small values of Seebeck coefficient (9 -14 µV K -1 at 300 K) and power factor (0.04 -0.07 mW m -1 K -2 at 300 K), due to too large hole concentrations (2.9 -7.6 × 10 20 cm -3 ). The lattice thermal conductivity was small (λL = 1.5 W m -1 K -1 ), as expected from the overall trend in the ACuSb series (A = Ca, Sr, Ba, Eu, Yb) and from the heavy atomic mass of Yb. Nonetheless, the modest values of power factor led to small values of thermoelectric figure of merit: maximum ZT = 0.09 at 700 K
Le consumérisme digital au service des transitions socio-environnementales ? Le cas d’une start-up spécialisée dans l’évaluation sociétale des produits alimentaires
No full textInternational audienceNous proposons dans cette communication une étude de cas empirique de la startup myLabel, qui propose une forme de consumérisme digital permettant aux consommateurs d'acheter des produits alimentaires conformes à leurs attentes en matière d'éco-responsabilité et subséquemment de fournir aux distributeurs des données sur les choix des consommateurs dans le but de favoriser l’émergence d’une offre de produits plus durables. L'application est très innovante par rapport aux autres dispositifs de consommation digitale, car elle permet de créer des scores personnalisés en fonction des appétences individuelles pour les sujets sociaux et environnementaux priorisés par les consommateurs eux-mêmes. L’objectif de la communication est d’explorer si et comment le processus innovant de myLabel permet une meilleure acceptation sociale des transformations socio-environnementales par les consommateurs comme les producteurs et distributeurs afin de contribuer à l’évolution des marchés vers plus de durabilité