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Acquérir le vocabulaire des émotions en maternelle
No full textSupporting children in understanding and expressing their emotions as soon as they enter kindergarten is essential to promote their well-being and social interactions. This thesis deals with how disciplinary transversality can promote the acquisition of the vocabulary of emotions in the first year of kindergarten. The research work highlights the role of an experiment based on a transversal approach aimed at enriching pupils’ vocabulary in two distinct classes. It questions the factors that could constitute limits or levers for them. The data obtained through individual interviews and an evaluation grid show different developments according to the profiles of the students: they illustrate the importance of the influence of contextual and individual factors in the appropriation of this specific vocabulary. As an example, a class stands out with students who have memorized and used 19 of the 21 expected words.Accompagner les enfants dans la compréhension et l’expression de leurs émotions dès l’entrée en maternelle est primordial afin de promouvoir leur bien-être et leurs interactions sociales. Ce mémoire s’intéresse à la manière dont la transversalité disciplinaire peut favoriser l’acquisition du vocabulaire des émotions en petite section. Le travail de recherche réalisé met en lumière le rôle d’une expérimentation fondée sur une approche transversale ayant pour objectif d'enrichir le vocabulaire des élèves dans deux classes distinctes. Elle questionne les facteurs qui pourraient constituer des limites ou des leviers à leur égard. Les données obtenues grâce à des entretiens individuels et à une grille d’évaluation montrent des évolutions différentes en fonction des profils des élèves : elles illustrent l'importance de l'influence des facteurs contextuels et individuels dans l'appropriation de ce vocabulaire spécifique. À titre d'exemple, une classe se distingue avec des élèves qui ont mémorisé et employé 19 des 21 mots attendus
Community Structure and Functioning of Soil-dwelling Macro-invertebrates in Cocoa Plantations Invaded by the Little Fire Ant and Neighboring Secondary Forest in Mbalmayo Reserve Forest (Centre-Cameroon)
No full textInternational audienceAgroforestry leads to the degradation of natural forests, floral and faunal biodiversity. Little information exists on faunal functioning in agroforestry environments invaded by exotic pests compared to natural environments. Ecological survey was conducted from September to November 2023 in Mbalmayo Reserve Forest (Centre-Cameroon), the community structure and functioning of macro-invertebrates in cocoa plantations invaded by the little fire ant, were compared to the situation in neighboring secondary forest. Baits, pitfall, and quadrats allowed collection of 129,916 specimens of seven classes, 18 orders, 39 families, and 82 species. Insecta was mostly abundant (cocoa plantations: 92.7%, secondary forest: 6.97%, pooled sites: 99.7%), as well as Hymenoptera (cocoa plantations: 92.6%, secondary forest: 6.80% of 13 species, pooled sites: 99.4% of 14 species). Cocoa plantations and secondary forest presented each low species richness, diversity, and evenness, and a high dominance by a few species. Cocoa plantations presented more exotic species (92.9%, 25 species) while secondary forest showed mostly natives of unknown pest status and few native pests. The little fire ant was abundant (92.6%) and dominant exclusively in cocoa plantations. In secondary forest, Myrmicaria opaciventris, Crematogaster gabonensis, and Pheidole megacephala were abundant in the dry season, the two former being co-dominants while in the rainy season Cr. gabonensis, Cr. striatula, Craspedophorus bonvouloirii, My. opaciventris, Ph. speculifera, and Paltothyreus tarsatus were abundant, the four former being co-dominants. A low dissimilarity was noted between the two sites. The change in species composition from cocoa plantations to secondary forest was relatively large. Armadillidium vulgare Latreille, 1804 (Armadillidiidae) and Wasmannia auropunctata Roger, 1863 (Formicidae) were good indicators of disturbed environments. Assemblage functioned on the basis of maintaining a multi-species network developed in time and space for the circulation of the information, but with a weak force of regeneration. The secondary forest undergrowth was unfavorable for exotics and in-depth studies would be conducted on the behavior of natives in relation to the progression of invasions, since cases of repellency have been recorded. Policy makers responsible for green space management should take effective measures to prohibit the transfer of plants infested with exotic pest species between invaded and non-invaded areas when creating agroforestry areas
Intérêt et engagement des élèves à travers le jeu en Éducation au Développement Durable
No full textOn the one hand, Education for Sustainable Development (ESD) in schools is essential for preparing students to become responsible, thoughtful, and engaged citizens. By addressing topics such as resource management, environmental preservation, and social and economic issues, this education helps students better understand current global challenges and adopt more sustainable behaviors. On the other hand, play holds a crucial place in children's development and plays a key role in their learning. As a pedagogical tool, it provides a stimulating environment for students. By combining a lesson in the “Exploring the World” domain (kindergarten) or science (Cycle 3) on cyclones with play-based activities in three classes—Petite Section, Moyenne Section, and Cour Moyen 1—we can observe the evolution of students' skills before and after the lesson.D’une part, l'éducation au développement durable (EDD) à l'école est essentielle pour préparer les élèves à devenir des citoyens responsables, réfléchis et engagés. En abordant des thèmes tels que la gestion des ressources naturelles, la préservation de l'environnement et les enjeux sociaux et économiques, cette éducation permet aux élèves de mieux comprendre les défis mondiaux actuels et d'adopter des comportements plus durables. D’autre part, le jeu occupe une place essentielle dans le développement des enfants et joue un rôle clé dans leurs apprentissages. En tant qu'outil pédagogique, il offre un environnement stimulant pour les élèves. En combinant une séquence dans le domaine explorer le monde (maternelle) ou sciences (cycle 3) sur le cyclone et le jeu dans les 3 classes de Petite Section, Moyenne Section et Cour Moyen 1, nous pouvons observer l’évolution des compétences des élèves en amont et en aval de la séquence
Représentations des Maisons de Santé Pluriprofessionnelles (MSP) pour les internes de médecine générale à La Réunion
No full textBackground : Multidisciplinary Health Centers (MSPs) address medical workforce challenges and young GPs’ expectations, but development in La Réunion remains limited. This study explores interns' perceptions, motivations, and barriers to identify drivers of attractiveness.Method: Qualitative research using semi-structured interviews with 5th- and 6th-semester interns in La Réunion, analyzed with inductive thematic coding.Results: Interns value group practice for support and collaboration but highlight administrative constraints and economic knowledge gaps. Three profiles: “Independents” (autonomous, less attracted), “Collaboratives” (innovation and teamwork-focused), “Community-Oriented” (socially engaged but averse to constraints).Conclusion: MSPs are appealing but need improvement: communication, training, and administrative support are essential.Introduction : Les Maisons de Santé Pluriprofessionnelles (MSP) pourraient répondre aux attentes des jeunes médecins, mais leur développement reste limité à La Réunion. Cette étude analyse les perceptions, motivations et freins des internes pour identifier des leviers d’attractivité.Méthode : Recherche qualitative basée sur des entretiens semi-dirigés avec des internes de 5ᵉ et 6ᵉ semestre à La Réunion, analysés par codage thématique inductif.Résultats : Les internes préfèrent l’exercice de groupe, mais craignent les contraintes administratives. Trois profils : « Indépendants » (autonomes, peu attirés), « Collaboratifs » (motivés par l’innovation et le travail en équipe), « Communautaires » (engagés socialement).Conclusion : Les MSP séduisent mais peuvent être perfectibles : communication, formation et soutien administratif sont essentiels
Reversible degradation detection-identification-avoidance and deep-learning co-driven fuel cell remaining useful life prediction
No full textInternational audienceA major obstacle to achieving large-scale applications of fuel cells in smart cities is the lack of durability of the stack. Accurate prediction of the Remaining Useful Life (RUL) of a fuel cell becomes a key prerequisite for enhancing its durability. However, reversible degradation behavior in fuel cell operation not only challenges the reliability of degradation trend prediction, but also affects the accurate estimation of RUL. To address this issue, this work proposes a reversible degradation detection-identification-avoidance and deep learning codriven prognostic strategy. Diagnostic techniques are utilised to detect and isolate reversible degradation. The interference of data imbalance on model training is improved by a data augmentation approach incorporating physical knowledge. The prognostic strategy proposed in this paper is validated on a dynamic operating conditions dataset, and the results show an average improvement of 22% to 62% in the prognostic horizon matching rate.</div
Temperature-dependent versatility shapes invasiveness in the tropical freshwater gastropod Melanoides tuberculata: Versatility shapes invasiveness in M. tuberculata
No full textInternational audienceInvasive species cause major losses in biodiversity worldwide and alter ecosystem functioning. Once established, invaders are often impossible to remove from ecosystems, especially in eco-insular systems such as the African Great Lakes. How intrinsic biological properties of invasive taxa interact with human-induced ecosystem modifications is a crucial factor determining invasiveness and our ability to anticipate, prevent and manage bioinvasions. Here we investigate the influence of temperature on key life-history traits, including fecundity, growth, offspring size, survival and parental immune investments, of invasive Asian Melanoides tuberculata (Müller, 1774) from Lake Malawi/ Nyassa (morph LMI). We subjected populations of this parthenogenetic (clonal) lineage to uniform temperature treatments of 20 °C, 26 °C and 32 °C and monitored adult and juvenile life-history traits. Constitutive (preventative) and infection-induced immune investments of adults were estimated via antibacterial responses to a natural pathogen. Fecundity was low during our experiment and did not differ amongst temperature treatments, but a burst of offspring release occurred in the first two weeks of the experiment. Juvenile size and growth increased with temperature, which resulted in decreasing generation times. Juvenile mortality was, however, elevated at 32 °C. Temperature differences prompted a shift in immune investments. Under cold temperatures, adults invested in costly constitutive immunity, but they did not in warm environments, where strong investments in infection-induced immune responses occurred. This strategy may enable adults in warm environments to redirect energy from immunity to growth and reproduction, therewith, enhancing competitiveness at the cost of reduced offspring survival. We observed contrasting responses in various studied traits, suggesting that Melanoides tuberculata adopts compensatory mechanisms to cope with environmental changes. This versatility favours invasiveness and contributes to the competitive pressure which invasive Melanoides exerts on native taxa amid global warming and ecosystem change. Understanding the intricate interactions between bioinvasions and environmental change is essential for effective conservation of native species, the stability of their ecosystems and for policy development. Species-specific versatility of invasive species and associated competitive advantages remain understudied, but are critical to predict invasion dynamics in the context of multidimensional anthropogenic stressors, for informed risk assessment and decision-making.</div
Maternidad, muertas vivientes y horror en las novelas [Ella] (2012) y Esa muerte existe (2016) de Jennifer Thorndike
No full textInternational audienc
ANALYSE DES EFFETS NON-LINEAIRES DE LA VOLATILITE DU TAUX DE CHANGE SUR L'INFLATION EN REPUBLIQUE DEMOCRATIQUE DU CONGO DE 1970 à 2022
No full textInternational audienceThis study takes part in the debate about nature of the relationship between exchange rate fluctuations and inflation. The goal is to demonstrate that the exchange rate evolves in a volatile manner, and that its effects on inflation are positive and non-linear for the case of the Democratic Republic of Congo (DRC), with annual data for the period from 1970 to 2022. Two econometric models are fitted for this purpose : (i) the Generalized Autoregressive Conditional Heteroscedasticity (GARCH) model, which was developed by Robert Engle, F., (1986); (ii) the Nonlinear Staggered Lag Autoregressive (NARDL) model, which was developed by Shin, Y.; Yu, B. C., and Greenwood-Nimmo, M. (2014). The results obtained from the estimations attest to the following : (i) the exchange rate in the DRC evolves in a volatile manner ; (ii) in the short term, the effects of exchange rate volatility on inflation are positive and non-linear, while they are linear in the long term. Positive shocks have an inflationary effect ; while negative shocks have a negative and statistically insignificant effect (prices are rigid to exchange rate depreciation in the DRC).Cette étude participe au débat sur la nature de la relation entre les fluctuations du taux de change et l'inflation. L'objectif est de démontrer que le taux de change évolue de manière volatile, et que ses effets sur l'inflation sont positifs et non-linéaires pour le cas de la République Démocratique du Congo (RDC), avec les données annuelles pour la période allant de 1970 à 2022. A cet effet, deux modèles économétriques ont été construits : (i) le modèle d'Hétéroscédasticité Conditionnelle Autorégressive Généralisée (GARCH), qui a été développé par Robert Engle, F., (1986) ; (ii) le modèle autorégressif à retard échelonné non-linéaire (NARDL), qui a été développé par Shin, Y. ; Yu, B. C., et Greenwood-Nimmo, M. ( 2014). Les résultats obtenus des estimations attestent ce qui suit : (i) le taux de change en RDC évolue de manière volatile ; (ii) à court terme, les effets de la volatilité du taux de change sur l'inflation sont positifs et non-linéaires, tandis qu'ils sont linéaires à long terme. Les chocs positifs ont un effet inflationniste, alors que les chocs négatifs ont un effet négatif et statistiquement non significatif (les prix sont rigides à la baisse du taux de change en RDC).</div
Link between crustal thickness and Moho transition zone at 9°N East Pacific Rise
No full textInternational audienceOceanic crust is formed from basaltic melt produced by decompression melting due to mantle upwelling at mid-ocean ridges. This crust is separated from the underlying mantle either by a sharp Mohorovičić (Moho) discontinuity or a thick Moho transition zone (MTZ). Determining the relationship between the oceanic crustal structure and the MTZ is critical for understanding the crustal accretion processes at mid-ocean ridges. However, this relationship remains elusive due to the lack of high-resolution velocity model of the oceanic crust and MTZ. Here, we present result from the application of full waveform inversion to wide-angle seismic data acquired over a young oceanic crust near the 9°N East Pacific Rise, allowing us to obtain the crustal and MTZ thicknesses along a ∼70 km-long segment. We find that the crustal thickness and the MTZ thickness vary along the segment and they are inversely correlated, although the total cumulative thickness does not vary much along the profile. These variations could be attributed to the different melt migration efficiency or the variations in mantle thermal/chemical structure, indicating mantle heterogeneity along the ridge
Steady-State Dune Morphodynamics Through the Barchan-Parabolic Transition
No full textInternational audienceDunes in the presence of vegetation exhibit a variety of shapes, from barchan to parabolic forms. Given the rapid fluctuations in environmental conditions across space and time, it is challenging to ascertain whether these dune shapes are merely transient or indicative of a dynamic equilibrium between sediment transport and vegetation growth. In this study, plant cover is introduced into a 3D cellular automaton dune model to numerically investigate the influence of vegetation on dune morphodynamics. Numerical simulations show that isolated parabolic dunes are unstable, increasing or decreasing in size according to the volume of vegetated sediment they remobilize downstream or deposit upstream in their horns. When specific boundary conditions are applied, dunes converge on steady states that accurately capture the barchan-parabolic transition. Most of the isolated dune shapes observed in nature are reproduced at steady state in the model by increasing the intensity of vegetation processes, from the typical migrating barchans to the fully stabilized parabolic dunes. As the impact of vegetation increases, the steepness of the steady-state dune slopes changes, and the crest curvature reversal occurs. This ensures that all the longitudinal sections of the dune migrate at the same rate by reorienting the transverse sediment fluxes. In the model parameter space, sudden jumps in steady-state properties are associated with the stabilization of upstream horns or crest curvature reversals. These results illustrate why transitional dune shapes between barchans and parabolic dunes are less common in natural environments where environmental conditions are heterogeneous and variable in both space and time