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Subjective Quality Assessment of Foveated Omnidirectional Images in Virtual Reality
No full textInternational audienceThis study presents a novel dataset called "Foveated Omnidirectional Image Quality Assessment" (FOIQA) for the subjective quality evaluation of foveated 2D omnidirectional images. This dataset addresses the limitations of existing datasets by leveraging a high-resolution head-mounted display and a gaze-contingent evaluation approach. We provide individual opinion scores, mean opinion scores, and gaze data associated with both the test and reference images. The utility of our dataset is validated by benchmarking two existing objective foveated image quality metrics. Our results demonstrate that incorporating gaze data into the evaluation framework improves the accuracy of one of the tested objective metrics.The dataset is publicly available at https://doi.org/10.5281/zenodo.14009106
Compétences et Méthodes d’Evaluation du Raisonnement Analogique chez les Personnes avec Trouble du Développement Intellectuel (TDI) : revue systématique de littérature
No full textInternational audienceLe raisonnement analogique se définit comme la capacité à élaborer des liens de similarités structurelles entre une situation ou un problème connu (i.e., la source) et une situation ou un problème nouveau (i.e., la cible) (Gentner, 1983, 1989; Holyoak, 1984). Les classifications actuelles des Troubles du Développement Intellectuel (TDI) font état d’altérations du fonctionnement cognitif (APA, 2013), comprenant des déficits de raisonnement (Greenspan & Woods, 2015), et la littérature scientifique relate plus particulièrement une altération des compétences de raisonnement analogique au sein de cette population (Curie et al., 2016). Malgré l’augmentation du nombre de publications sur le sujet, nous ne pouvons que constater le manque de consensus sur la question du développement des compétences de raisonnement analogique en population TDI, et des méthodes de mesure de ces compétences adaptées à cette population. Nous remarquons par exemple que des outils utilisés pour évaluer les compétences de raisonnement analogique peuvent également être utilisés par d’autres auteurs pour mesurer d’autres fonctions cognitives ou pour estimer plus largement le niveau de raisonnement non-verbal (e.g., Matrices Progressives de Raven). L’objectif de notre étude est de proposer une revue systématique de la littérature sur les compétences de raisonnement analogique en population TDI et sur les moyens existants de mesure de ces compétences. Notre revue systématique, préenregistrée sur PROSPERO, a été conduite sur la base de la méthodologie PRISMA. Les articles sélectionnés dans le cadre de cette revue systématique ont été choisis à partir des bases de données bibliographique Scopus, PsycINFO et PubMed, et évalués conformément aux critères JBI. L’examen de la littérature nous a permis d’identifier trois différentes approches dans l’étude du raisonnement analogique : l’approche perceptuelle standardisée et basées sur des tâches de matrices (e.g., Curie et al., 2016) ; l’approche conceptuelle standardisée et basée sur des listes de relations sémantiques (e.g., Boehm Test of Basic Concepts) ; et les analogies construites pour être conduites en contextes expérimentaux (e.g., tâches A:B::C:D ; scene analogy tests, etc.). Nous discuterons les forces et faiblesses de ces différentes approches, en allouant notamment un intérêt particulier au type de mesure (i.e., évaluation de la compréhension vs de la production d’analogies, mesures comportementales, utilisation de l’eye-tracking, etc.). Les résultats de cette revue ont pour objectif de tenter de centraliser les informations existantes sur le raisonnement analogique en population TDI, notamment en ce qui concerne les différents outils et les différentes méthodologies d’évaluation de ces compétences au sein de cette population, dans le but de servir de base théorique et méthodologique pour de nouvelles expérimentations dans le domaine du raisonnement analogique en population TDI
Current Advances in the Combination of Fatty Acids and Resveratrol to Fight Ocular Diseases
No full textInternational audienceOmega‐3 polyunsaturated fatty acids (PUFA) and polyphenols have attracted interest to counteract ocular diseases and more specifically age‐related macular degeneration (AMD). This eye disease, which is the leading cause of irreversible blindness in industrialized countries, is characterized by damage to the central part of the retina, the macula. Despite therapeutic advances with the use of anti‐vascular endothelial growth factor (VEGF) monoclonal antibodies, numerous resistance mechanisms that worsen visual impairment have been identified. In this context, we highlight the exceptional potential of polyphenols and PUFA in addressing AMD through their actions on the different molecular mechanisms involved in AMD progression. More specifically, this review focuses on the current understanding of the effects of resveratrol, as well as docosahexaenoic and eicosapentaenoic acids, two prominent omega‐3 PUFA, and the combination of these compounds. We also discuss the limitations and explore future directions for the combined use of these natural products as preventive or complementary therapies to preserve vision and slow disease progression
FlorSys: A mechanistic model bridging scientists, advisors and farmers in order to design agroecological weed management strategies
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/614347/)International audienc
The Combinatorics of Motzkin Polyominoes
No full textInternational audienceA word over the set of positive integers is a Motzkin word whenever , , and for . It can be associated to a -column Motzkin polyomino whose -th column contains cells, and all columns are bottom-justified. We reveal bijective connections between Motzkin paths, restricted Catalan words, primitive {\L}ukasiewicz paths, and Motzkin polyominoes. Using the aforementioned bijections together with classical one-to-one correspondence with Dyck paths avoiding s, we provide generating functions with respect to the length, area, semiperimeter, value of the last symbol, and number of interior points of Motzkin polyominoes. We give asymptotics and close expressions for the total area, total semiperimeter, sum of the last symbol values, and total number of interior points over all Motzkin polyominoes of a given length. We also present and prove an engaging trinomial relation concerning the number of cells lying at different levels and first terms of the expanded
La biopolitique de Foucault et les études littéraires : lire la fiction dystopique et/ou postapocalyptique
No full textInternational audienc
Experimental analysis of metamaterial with improved high sound levels absorption using complex frequency plane
No full textInternational audienceThis study proposes using the complex frequency plane representation as a tool to quantify loss levels of a metamaterial at low sound levels, enabling the prediction of trends in absorption coefficient changes at high sound levels. A multi-resonant metamaterial composed of a series of thin annular cavities connected by a central perforation is considered which has been previously studied in the linear regime. With the analytical model developed for the linear regime, the representation of the complex frequency plane allows understanding whether a low value of absorption peak is due to excessive losses or, instead, to a lack of losses in the material. As sound level increase, material losses rise, leading to decrease in absorption peaks for structures with excessive losses and increase of peak absorption coefficient values for those with insufficient losses. Multi-resonant metamaterials with a constant main pore profile are selected to exhibit resonances with various loss levels, and measurements in a high sound level impedance tube are conducted to validate the expected changes in absorption coefficient. After that, an acoustic black hole is considered and a structure with two low frequency absorption peaks increasing with sound level and presenting a broad absorption band with low sensitivity to high sound levels is identified. The predictions are validated experimentally
Anxio-depressive phenotype and impaired memory in mice with a conditional knockout of brain-derived neurotrophic factor in endothelial cells
No full textInternational audienceThe present study investigated the role of endothelial brain-derived neurotrophic factor (BDNF) in cognition. Male adult micewith a selective knockout of BDNF in endothelial cells (BDNFECKO) and their wild-type (WT) littermates were subjected to testsfor detection of anxiety- and depression-like behaviors and impaired recognition memory. Neuronal activity and synaptogenesiswere assessed from hippocampal levels of c-fos and synaptophysin, respectively, and cerebral capillary density from forebrainlevels of CD31. BDNF/TrkB (tropomyosin-related kinase type B) receptor signaling was investigated through hippocampal levelsof BDNF and activated TrkB receptors coupled with their immunolabeling by neurons and endothelial cells from both cerebrovascularfractions enriched in capillaries and hippocampal arterioles. Endothelial nitric oxide (NO) production was assessed fromthe expression of endothelial NO synthase phosphorylated at serine 1177. BDNFECKO mice exhibited anxio-depressive phenotype,impaired memory, and reduced synaptogenesis. Neither neuronal activity, neuronal BDNF/TrkB signaling, nor capillary densitydiffered between BDNFECKO and WT mice. However, endothelial-activated TrkB receptors as well as endothelial NO productionand hippocampal BDNF levels were lower in BDNFECKO than those in WT mice. We conclude that endothelial BDNF is involvedin cognition through mechanisms independent of neuronal BDNF/TrkB signaling and that endothelial NO might be a driver ofthe procognitive effect of endothelial BDNF
Enseignants : le grand déclassement ?
No full textInternational audienceL'enseignement fait l'objet d'une forte perte d'attractivité, comme le suggèrent la baisse continue des candidatures aux concours de recrutement et la hausse tendancielle des démissions. Le temps où ces métiers étaient investis comme un sacerdoce semble révolu. Cet ouvrage propose d'explorer les différents facteurs et effets de cette érosion des corps enseignants, qui n'est pas propre à la France. Il invite ainsi à prêter attention non seulement aux rémunérations, mais aussi aux politiques de recrutement et de gestion des carrières enseignantes, aux transformations des conditions d'entrée dans le métier comme de son exercice quotidien, au sentiment de valorisation sociale ainsi qu'aux attitudes politiques. Sans perdre de vue que le milieu enseignant est touché par des évolutions sociales qui traversent également d'autres groupes professionnels
Why oaks should stay with their close relatives: growing in a distantly related neighbourhood delays and reorganizes nutrient recycling during litter decomposition
No full textInternational audienceClosely related species often conserve similar niches despite interacting negatively. We suggest that close relatives may interact positively via ecosystem feedbacks: leaf litter produced or exposed in a closely related neighbourhood (low phylogenetic isolation) may decompose more quickly, leading to more rapid nutrient recycling. We studied decomposition of leaf litter of oaks Quercus petraea across 8 and 14 months, reciprocally transplanting leaf litters between low and high phylogenetic isolation to distinguish between effects mediated by leaf litter quality and by decomposition environment. We found that, by affecting litter quality, phylogenetic isolation reduced decomposition across 14 months (loss of litter mass and C). Moreover, by affecting litter quality and decomposition environment, phylogenetic isolation reduced microbial biomass and extensively altered relationships between C and N losses and abundances/diversities of different soil organisms across 8 and 14 months. Phylogenetic isolation was to a large extant driven by percentage of gymnosperms, explaining the decomposition‐environment mediated effects. Such environment‐mediated effects reflected decreasing soil humidity and pH with phylogenetic isolation, while litter‐quality mediated effects reflected decreasing leaf phytophagy or increasing leaf phenolics. Tree‐species richness, in contrast, did not explain effects of phylogenetic isolation, and had little effect overall. To conclude, coexistence of oaks with distant relatives partly impedes recycling of leaf litter and re‐organizes the trajectories of this recycling. In contrast, oaks coexisting with close relatives may profit from a positive ecosystem feedback through increased nutrient recycling, possibly contributing to the conservation of the oak's niches. We suggest that such a positive ecosystem feedback among close relatives might exist in other late successional tree species