HAL Portal UPF (Université de la Polynésie française)
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Les politiques de scolarisation pour l’Outre-mer. Bilan pour la Commission nationale consultative des droits de l'Homme
No full textCe diaporama a été présenté lors de l'audition à la Commission nationale consultative des droits de l’Homme (CNCDH), sous-commission A (scolarisation), qui s'est tenue à Paris le 16 janvier 2024. Dans cette communication, l'auteur présente un bilan (catastrophique) des politiques éducatives et de la situation de la scolarisation dans la France d'Outre-mer
Pearl Farming Micro-Nanoplastics Affect Oyster Physiology and Pearl Quality
No full textInternational audiencePearl farming is crucial for the economy of French Polynesia. However, rearing structures contribute significantly to plastic waste, and the widespread contamination of pearl farming lagoons by microplastics has raised concerns about risks to the pearl industry. This study aimed to evaluate the effects of micro-nanoplastics (MNPs, 0.4–200 μm) on the pearl oyster (Pinctada margaritifera) over a 5-month pearl production cycle by closely mimicking ecological scenarios. MNPs were produced from weathered plastic pearl farming gear and tested at environmentally relevant concentrations (0.025 and 1 μg L–1) to decipher biological and functional responses through integrative approaches. The significant findings highlighted the impacts of MNPs on oyster physiology and pearl quality, even at remarkably low concentrations. Exposure to MNPs induced changes in energy metabolism, predominantly driven by reduced assimilation efficiency of microalgae, leading to an alteration in gene expression patterns. A distinct gene expression module exhibited a strong correlation with physiological parameters affected by MNP conditions, identifying key genes as potential environmental indicators of nutritional-MNP stress in cultured oysters. The alteration in pearl biomineralization, evidenced by thinner aragonite crystals and the presence of abnormal biomineral concretions, known as keshi pearls, raises concerns about the potential long-term impact on the Polynesian pearl industry
L’évolution statutaire et l’affirmation de l’autonomie des territoires français du Pacifique (1946-2004)
No full textInternational audienceCet article a pour objectif de faire une brève synthèse et une rétrospective de l’histoire de l’évolution statutaire et de l’autonomie des territoires français du Pacifique. Si l’historiographie foisonne, elle n’est abordée et renouvelée que par une poignée de chercheurs en France. La Polynésie française, la Nouvelle-Calédonie et les îles Wallis et Futuna sont toujours des territoires autonomes de la République française au sein d’un océan Pacifique décolonisé. De 1946 à 2004, le statut et les institutions de ces territoires évoluent plus ou moins vers l’autonomie, pour le meilleur et pour le pire, selon les intérêts de la France dans le Pacifique Sud. L’autonomie, portée par des hommes charismatiques, locaux comme nationaux, défendant une singularité au sein même de l’outre-mer français, devient un outil majeur à la fois pour l’affirmation politique de ces territoires et leur conservation pour Paris. Entre enjeux politiques, économiques et militaires à toutes les échelles, la France, qu’elle soit « dans » ou « de » cette région, pour emprunter les mots de Denise Fisher, peine toutefois à décoloniser ce « monde du Pacifique », selon l’expression du général de Gaulle, si ce n’est à l’intégrer pleinement dans la République
The Underrealized Ecocritical Potential of ABZÛ
No full textInternational audienceIn recent years, diving ecogames have become an increasingly popular video game subgenre that seems to hold out the promise of raising awareness about environmental issues. In this chapter, a content analysis of the diving video game ABZU highlights its ecocritical potential despite its hints of speciesism, orientalism, and techno-solutionism. A reception study of the game, based on 2,421 comments published on fourteen platforms, however, shows that only fifty-six players mention its environmentalist message . Nevertheless, most of these commenters do pick up on the ecocritical potential of ABZU , sharing their thoughts with other players. Online forums therefore appear as discussion spaces where collective ecological awareness can develop
Premier desserrement de la politique monétaire des collectivités françaises du Pacifique
No full textArticle de vulgarisation scientifiqueDans notre article du 1er juin, Le gouvernement a-t-il réellement « stoppé l’inflation » ?, nous concluions s’agissant de la Polynésie française que « L’inflation peut dorénavant être considérée comme jugulée, au moins pour l’instant (il conviendra de voir l’impact éventuel du desserrement des politiques monétaires qui est prochainement à venir) ». Il n’aura pas fallu attendre bien longtemps, comme prévu, pour vérifier cet enclenchement de la baisse des taux.Article disponible sur le lien suivant :https://www.pacific-pirates-media.com/?s=Premier+desserrement+de+la+politique+mon%C3%A9taire+des+collectivit%C3%A9s+fran%C3%A7aises+du+Pacifiqu
: Assessment of therapeutic response by FDG-PET in solid tumors (PERCIST 1.0 criteria)
No full textInternational audience18F-Fluoro-Deoxyglucose (FDG) Positron Emission Tomography (PET) is an imaging technique used to study glucose metabolism in cells. It is particularly useful in oncology, especially for initial diagnosis and the detection of recurrence. Thanks to its functional approach to tissues, its use has evolved towards the evaluation of anticancer treatments, both in a personalized approach to patients and as part of clinical trials of new biotherapies. This technique provides additional information compared to conventional imaging, which is not always able to assess tumor viability of potentially necrotic or fibrotic residual masses after treatment. However, the use of FDG-PET requires a rigorous methodology, both for the performance of the studies and for their interpretation. Based on a large body of literature, interpretation criteria for solid tumors have been published and updated. PERCIST 1.0 (Positron Emission Tomography Response Criteria In Solid Tumors), proposed by an American task force in 2009, aims to clarify and standardize practice. These criteria will evolve according to the specificities of new biotherapies such as immunotherapy.La tomographie par émission de positons (TEP) au 18F-Fluoro-desoxyglucose (FDG) est une technique d’imagerie permettant d’étudier le métabolisme glucidique des cellules. Elle est particulièrement utile en oncologie, notamment pour le diagnostic initial et la recherche de récidive. Grâce à son approche fonctionnelle des tissus, son utilisation a évolué vers l’évaluation des traitements anticancéreux, aussi bien dans une approche personnalisée des patients que dans le cadre d’essais cliniques de nouvelles biothérapies. Cette technique offre des informations supplémentaires par rapport à l’imagerie conventionnelle, qui ne permet pas toujours d’évaluer la viabilité tumorale des masses résiduelles potentiellement nécrosées ou fibrosées après traitement. Cependant, l’utilisation de la TEP-FDG nécessite une méthodologie rigoureuse, tant pour la réalisation des examens que pour leur interprétation. Sur la base d’une littérature de plus en plus complète, des critères d’interprétation pour les cancers solides ont été publiés et mis à jour. La version PERCIST 1.0 (Positron Emission Tomography Response Criteria In Solid Tumors), proposée par un groupe de travail américain en 2009, vise à clarifier et homogénéiser les pratiques. Ces critères sont amenés à évoluer pour s’adapter aux spécificités de nouvelles biothérapies comme l’immunothérapie
The Generalization Error of Supervised Machine Learning Algorithms
No full textIn this paper, the method of gaps, a technique for deriving closed-form expressions in terms of information measures for the generalization error of supervised machine learning algorithms is introduced. The method relies on the notion of \emph{gaps}, which characterize the variation of the expected empirical risk (when either the model or dataset is kept fixed) with respect to changes in the probability measure on the varying parameter (either the dataset or the model, respectively). This distinction results in two classes of gaps: Algorithm-driven gaps (fixed dataset) and data-driven gaps (fixed model). In general, the method relies on two central observations: ~The generalization error is the expectation of an algorithm-driven gap or a data-driven gap. In the first case, the expectation is with respect to a measure on the datasets; and in the second case, with respect to a measure on the models. ~Both, algorithm-driven gaps and data-driven gaps exhibit closed-form expressions in terms of relative entropies. In particular, algorithm-driven gaps involve a Gibbs probability measure on the set of models, which represents a supervised Gibbs algorithm. Alternatively, data-driven gaps involve a worst-case data-generating (WCDG) probability measure on the set of data points, which is also a Gibbs probability measure. Interestingly, such Gibbs measures, which are exogenous to the analysis of generalization, place both the supervised Gibbs algorithm and the WCDG probability measure as natural references for the analysis of supervised learning algorithms. All existing exact expressions for the generalization error of supervised machine learning algorithms can be obtained with the proposed method. Also, this method allows obtaining numerous new exact expressions, which allows establishing connections with other areas in statistics, e.g., hypothesis testing and Pythagorean identities involving mutual information, lautum information, and/or relative entropies
Adoption of Covid-19 safety certification and pricing strategy in the hotel industry
No full textInternational audienceThe tourism sector has voluntarily undertaken several initiatives to boost customer confidence in response to the COVID-19 pandemic. For example, in the hotel industry, three different strategies have been implemented: sending no COVID-19 safety signal; sending a moderate signal through a charter; or sending a strong signal through a label. This study aims to identify the main drivers of the hotels’ choice among these strategies and to analyze the influence of their choice on price setting. We estimate a system of three equations (hotel pricing, star rating, COVID-19 safety signal) on a sample of 418 rated hotels in the Hauts-de-France region. Results support three main findings: 1) star rating positively correlates with COVID-19 certification; 2) COVID-19 certification has a strongly negative impact on hotel prices; 3) star rating moderates positively the effect of COVID-19 certification on prices. Furthermore, error terms between the star rating level and COVID-19 certification equations are strongly correlated. Hence unobserved common factors play a role in the adoption of these quality signals. Our findings are consistent with the idea that managers implementing safety signaling strategies are more worried about recovery speed after lockdowns
Social Structure and Habitat Use of New Caledonian Leopard Skinks (Scincidae: Lacertoides pardalis): A Radiotelemetric Study
No full textInternational audienc
Spawning window and fecundity in three Acroporid corals from the environmentally variable semi-enclosed lagoon of Bouraké
No full textInternational audienceThe gametogenic cycle in broadcast spawning corals takes several months, with oogenesis culminating in synchronized maturation when seawater temperatures rise. Temperature is known for governing reproductive seasonality, yet little is known about how multiple stressors may affect spawning timing. The semi-enclosed lagoon of Bouraké in New Caledonia is subjected to high fluctuations in seawater temperature, pH, salinity, and oxygen, representing an ideal playground to explore possible effects of extreme environmental variability on coral gametogenesis. Here, the spawning window and fecundity metrics (i.e., colony- and polyp-level fecundity, and egg size) of Acropora tenuis, Montipora digitata, and M. stellata from Bouraké were compared with four reference sites located at variable distances from Bouraké. Results suggest that Bouraké and its nearby control site largely spawned synchronously, but there was a spawning asynchrony between Bouraké and the sites further south, in all three species. Interestingly, no reduction in the number of eggs per fecund polyp or number of fecund polyps was observed in Bouraké compared with the reference sites, in any species. However, A. tenuis and M. digitata had smaller eggs in Bouraké compared to reference sites, with possible repercussions for coral fitness. In conclusion, some reproductive traits are maintained in coral species inhabiting a highly variable environment, but smaller gametes may alter population recovery processes. Furthermore, since our data are limited to 2 yrs of observations, spawning synchronization between Bouraké and its surroundings warrant continued investigation to determine whether coral colonies from this area harbor traits that increase fitness under future climate scenarios