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Dessin et valence émotionnelle
No full textThis study evaluates children’s capacity to represent emotional valence of an instruction for living and non-living objects drawing. One hundred and forty-two kids of 5, 7 and 11 years old made those drawings. Half of them drew a dog and the other half drew a house. The drawings were analysed through a graphic index (literals and non-literals), number and valence. The results told us that children can modify or transform their drawing depending on the emotional valence of an instruction by using an expressive graphic index. For each instruction (neutral, positive and negative valence) and each object, the young pupils make it more complex and increase the number of graphic indexes with age. Literals indexes were more used in dog drawings while non-literal indexes were more used in house drawings.Cette étude évalue la capacité des enfants à représenter la valence émotionnelle d’une consigne pour des dessins d’objets vivants et non-vivants. Cent quarante-deux enfants de 5, 7 et 11 ans ont réalisé des dessins, dont la moitié des chiens et l’autre moitié des maisons. Les dessins ont été analysés en termes d’indices graphiques (littéraux / non-littéraux), de nombre et de valence. Les résultats indiquent que les enfants sont capables de modifier leurs dessins en fonction de la valence émotionnelle de la consigne en utilisant des indices graphiques expressifs. Pour chaque consigne (valence neutre, positive, négative) et chaque objet, les élèves complexifient et augmentent le nombre d’indices graphiques avec l’âge. Les indices littéraux sont plus utilisés dans le dessin du chien tandis que les indices non-littéraux sont plus utilisés dans le dessin de la maison
Should I Wait or Should I Pay? The Dynamics of Private and Public Healthcare
No full textIn many countries, a private health system coexists with the public one. Recently, however, it seems that the latter is subjected to budgetary cuts and no longer able to meet the needs of citizens. Within an OLG model with production and in which young agents invest in preventive medicine and consume private healthcare beside public one, we prove that access to public health system is rationed by increasing waiting times, entailing costs in terms of treatment e!ectiveness and psychological order. Considering a fiscal policy aimed at providing health services, we prove that there emerge two dynamic regimes, the first prevailing for low GDP levels, the other for larger ones, where waiting times are countercyclical. We find two stationary capital levels, the lower one being globally unstable while the higher one globally stable. We also study the set of optimal allocations and prove that stationary GDP is increasing in the social discount factor. Finally, we show that it is possible to decentralize any optimal allocation by fixing opportunely the debt-to-GDP ratio and government spending in healthcare
On the singularities of the spectral shift function for some tight-binding models
No full textWe consider perturbed discrete tight-binding models in ℓ_2(ℤ,G) describing union of quantum particles with localized interactions, where ℤ_h is the 1D lattice hℤ, h>0, and G is a separable Hilbert space. The perturbations play the role of self-adjoint relatively compact (matrix-valued) electric potentials with B(G)-valued coefficients decaying polynomially at infinity. We analyze the Spectral Shift Function (SSF) associated to the pair of the perturbed and the unperturbed operators. On the one hand, we show that the SSF is bounded near the spectral thresholds of the essential spectrum if dim(G)<+∞. On the other hand, if dim(G)=+∞, we show that it may have singularities at some thresholds points μ of the essential spectrum. In particular, new mechanisms allowing the SSF to have singularities at the thresholds are exhibited, based on the degeneracy of the spectrum of the unperturbed operator. Moreover, we give the main terms of the asymptotic behaviors of the SSF near μ described in terms of some explicit effective Berezin-Toeplitz type operators. These results are completed by Levinson type formulas and examples of eigenvalues asymptotics for power-like and exponential decay potentials
L’impact des feedbacks sur la motivation des élèves en Éducation Physique et Sportive
No full textPhysical Education holds a fundamental position within the school curriculum. Beyond developing motor and social skills, it plays a key role in fostering student motivation and engagement in the learning process. Among the various pedagogical tools available to teachers, feedback stands out as a major factor. By providing information related to a specific situation and/or performance, feedback can significantly influence students’ sense of competence and motivation. This study examined the impact of feedback on student motivation in Physical Education depending on age. Specifically, we investigated the effects of three types of feedback — negative, delayed, and resultoriented — within the context of athletic activities. The objective of the experiment was to analyze the responses of students across cycles 1, 2, and 3 following the receipt of performance- related feedback. Our findings indicate that students in cycle 3 were more likely to experience a drop in motivation after receiving negative feedback, whereas students in cycle 1 appeared to be only minimally affected by such feedback. Contrary to our initial hypothesis, delayed feedback — which we assumed would increase motivation among older students — did not have the expected effect. No significant changes were observed from cycle 2 onward, but a slight decrease in motivation was noted among cycle 1 students. Lastly, result-oriented feedback appeared to negatively affect students in cycles 2 and 3, both of whom showed a decrease in motivation. These results underscore the necessity for teachers to tailor their feedback in Physical Education based on the students’ age.L’Éducation Physique et Sportive occupe une place primordiale à l’école. Au-delà du développement de compétences motrices et sociales, elle joue un rôle clé dans la motivation des élèves et leur engagement dans l’apprentissage. Parmi les leviers mobilisables par l’enseignant, les feedbacks occupent une place centrale. En fournissant des informations liées à une situation et/ou une performance, ils influencent le sentiment de compétence et la motivation des élèves. Nous nous sommes intéressés à l’impact des feedbacks sur la motivation des élèves en EPS en fonction de l’âge et plus particulièrement celui de trois types de feedbacks — négatif, différé et axé sur la connaissance du résultat — en nous appuyant sur l’activité athlétisme. L’objectif de notre expérimentation était alors d’analyser la manière dont des élèves des cycles 1, 2 ou 3 réagissaient après réception d’un feedback donné à la suite de leur performance. Il s’avère que les élèves de cycle 3 subissent davantage une baisse de motivation à la suite d’un feedback négatif contrairement aux élèves de cycle 1 pour qui cette rétroaction n’a eu qu’un faible impact. À l’inverse, le feedback différé, qui allait selon nous provoquer une augmentation de la motivation chez les plus grands, n’a pas eu l’effet escompté puisque qu’aucun changement n’a été observé à partir du cycle 2 tandis que la motivation des élèves de cycle 1 a légèrement chuté. Enfin, l’apport d’un feedback qui vise la connaissance du résultat semble toucher négativement les cycles 2 et 3 qui ont subit une baisse de motivation. Il semble alors indispensable pour l’enseignant d’adapter les feedbacks en EPS en fonction de l’âge des élèves
Le jeu et la motivation mathématique
No full textThis study examines the impact of mathematical games on student motivation and engagement in upper elementary education (Grade 4-5). Focusing on the ListenUp Géo game, the research explores how game-based activities strengthen student involvement and motivation in mathematics.The first section establishes the theoretical foundations of school motivation and didactic games, drawing from educational psychology and pedagogical frameworks. The second section analyzes an experiment conducted in a mixed-age classroom (CM1-CM2) using an observation grid and targeted student interviews.Results indicate that well-structured mathematical games enhance engagement, conceptual understanding, and enthusiasm among students.Key findings highlight that game-based learning fosters active participation, peer collaboration, and a positive attitude toward problem-solving.This work advocates for the regular integration of mathematical games to create more motivating and differentiated learning environments, ultimately supporting student success.Ce mémoire explore l’impact du jeu mathématique sur la motivation et l’engagement des élèves au cycle 3. Cette étude vise à comprendre comment une activité sous forme de jeu mathématique, ici le jeu ListenUp Géo, peut être utilisée pour renforcer l’implication des élèves et leur motivation.La première partie établit les fondements de la motivation scolaire et du jeu didactique, tandis que la seconde analyse l’expérimentation menée en classe de CM1-CM2 à travers une grille d’observation et des entretiens ciblés.Les résultats montrent que lorsque qu’une activité est complète et sous forme de jeu mathématique, elle favorise l’engagement, la compréhension et l’enthousiasme des élèves.Ce travail invite à intégrer régulièrement le jeu en mathématiques pour créer des environnements d’apprentissage plus motivants et différenciés afin de favoriser la réussite des élèves
Investigation on the Effect of Moisture Content in Mixed Substrates of Green Walls on Sound Diffraction
No full textInternational audienceGreen wall substrates composed of porous materials such as perlite, coconut peat, and coconut fiber offer dual environmental benefits by supporting vegetation and mitigating urban noise. This study investigates the acoustic performance of these substrates under varying moisture contents (0%, 30%, and 60%), focusing on their effects on sound absorption and diffraction. Surface impedance and absorption coefficients were experimentally measured and implemented in a Boundary Element Method (BEM) model to simulate sound attenuation at six receiver positions located 5 m and 10 m from a 2 m high barrier. Results show that dry mixtures (0% moisture) consistently deliver superior low-frequency attenuation (100-300 Hz), attributed to lower acoustic impedance and greater internal energy dissipation. As moisture content increases, pore saturation leads to higher impedance and diminished absorption, particularly at low frequencies. Performance differences are most evident in lit regions, where diffraction and interference effects are more complex. Importantly, the comparable performance of the 30% and 60% moisture substrates suggests that excess water offers limited acoustic benefit, supporting more sustainable water use. These findings highlight the critical role of moisture content in acoustic behavior and support the design of resource-efficient green wall systems for effective and ecofriendly urban noise control.</div
On the resilience of traditional AI algorithms toward poisoning attacks for vulnerability detection
No full textInternational audienceThe complexity of implementations and the interconnection of assorted systems and devices facilitate the emergence of vulnerabilities. Detection systems are developed to fight against this security issue, being the use of artificial intelligence (AI) a common practice. However, the use of AI is not without its problems, especially those affecting the training phase. This article tackles this issue by characterizing the resilience against poisoning attacks using a benchmark for vulnerability detection, extracting simple code features while applying traditional AI algorithms. These choices are beneficial for the fast processing of vulnerabilities required in a triage process. The study is carried out in C#, C/C++, and PHP. Results show that the vulnerability detection process is specially affected beyond 20% of false data. Remarkably, detecting some of the most frequent common weakness enumeration (CWE) is altered even with lower poison rates. Overall, K ‐nearest‐neighbor (KNN) and support vector machine (SVM) are the most resilient in C# and C/C++, while multilayer perceptron (MLP) in PHP. Indeed, vulnerability detection in PHP is less affected by attacks, while C# and C/C++ present comparable results
External biosecurity in outdoor pig farms: Gaps in fencing and wildlife control
No full textInternational audienceOutdoor pig farming is increasingly favoured by consumers due to its perceived benefits for animal welfare. However, ensuring adequate biosecurity remains a major challenge, particularly in preventing disease transmission between livestock and wildlife. This study aimed to evaluate key external biosecurity measures, with a focus on fencing, in 40 outdoor pig farms in France.Data were collected from free-range pig farms housing at least 30 animals. The presence, type, maintenance, and functionality of fencing were assessed, along with potential exposure to wildlife and contact, based on farmer interviews.Overall, 59% of farms did not comply with national biosecurity regulations designed to prevent contact with wild boar. Non-compliance varied by production stage: 54% of farms with outdoor farrowing, 29% with outdoor mating and gestation, 45% with outdoor quarantine, and 25% with outdoor finishing units. Electric fence integrity was deficient in 25% of mating and gestation areas and 19% of farrowing areas. Proper vegetation management around electric fences was conducted in 69% and 55% of farrowing and mating/gestation areas, respectively.Wild boars were observed near 75% of farms, with 43% of farms reporting sightings more than twice a year. Direct contact between wild boar and pigs occurred on 20% of farms, leading to pig-boar hybrids in two cases. Other frequently observed wildlife included foxes, hares, badgers, roe deer, cats, rabbits, martens, and crows. While 70% of farms employed fencing or trapping to mitigate fox intrusion, 5% implemented protective measures against crowsThese findings underscore the need to strengthen external biosecurity measures in outdoor pig farms to mitigate the risk of disease transmission from wildlife, particularly African swine fever
Multiphase tectonothermal events in the Indochina block, viewed from migmatitic rocks of the Kon Tum massif
No full textInternational audienceCrustal melting, represented by migmatite formed at various stages of orogenesis and in regions of thinned crust, plays a key role in understanding tectonic history. Migmatitic rocks are widespread in the Kon Tum massif, the southeastern part of Indochina, but their timing is still poorly constrained. The zircon (SIMS) U–Pb dating of representative migmatitic rocks and anatectic leucosome reveal three stages of crustal partial melting in the Kon Tum massif. These partial melting events involved three distinct geodynamic settings. The first one occurred at 450–440 Ma during Early Paleozoic collisional orogeny between Viet-Lao and Viet-Cambodia blocks along the Tam Ky-Phuoc Son suture. The newly identified second event took place at 370–360 Ma and was plausibly linked to the break-off of the Indochina-South China continent from the north rim of Gondwana. The third partial melting event, volumetrically the most developed, occurred as early as 260–250 Ma. This event involved the underplating magmatism and the extensional exhumation of the Kon Tum lower–middle crust
