HAL Portal UPF (Université de la Polynésie française)
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L’expérience émotionnelle du soin aux parents âgés chez les proches aidant.e.s : entre révélateur d’inégalités sociales « en train de se faire » et travail de régulation
No full textCette contribution documente et analyse l’expérience émotionnelle des aidant.e.s familiaux prenant soin à domicile d’un parent âgé dépendant, en Polynésie française. Ce territoire se caractérise par un vieillissement rapide de sa population et un modèle familialiste faiblement professionnalisé de prise en soin de la dépendance. À partir d’une enquête sociologique qualitative par entretiens auprès de 32 proches aidant.e.s résidant sur ce territoire, l’article met en évidence une différenciation des expériences émotionnelles du soin selon le niveau de soutien familial et institutionnel dont disposent les aidant.e.s. Les émotions apparaissent comme des expériences socialement situées, produites au croisement du genre, des conditions socio-économiques et du contexte institutionnel. Pour les aidant.e.s placé.e.s en position de « parent piégé » au sein de leur famille, plus particulièrement, l’expérience émotionnelle s’inscrit dans une dynamique de vulnérabilisation dont les coûts sont à la fois sociaux (ruptures conjugales, isolement social), économiques (sortie de l’emploi, appauvrissement) et psychiques (dépression, burn out). Pour maintenir, malgré tout, la relation de soin à leur parent, malgré les fortes contraintes que cette relation implique et les faibles compensations qui l’accompagnent, ces aidant.e.s sont amené.e.s à déployer un travail de régulation émotionnelle invisibilisé
A preliminary assessment of sediment toxicity and vulnerability of tropical marine species in the society islands, French Polynesia
No full textAquatic sediments act as reservoirs of multiple sources of pollutants, and the increasing urbanization of coastal marine areas generally contributes to the accumulation of contaminants, endangering aquatic life and biodiversity. In the present study, we assessed the toxicity of sediment, relative to negative control, sampled at 150 sites around six islands in the Society Archipelago, French Polynesia. This evaluation was based on the use of biological assays, during larval development of tropical benthic species in sediment elutriates. The results demonstrated a limited correlation in the responses of the three species studied: the sea cucumber Holothuria fuscogilva, the sea urchin Tripneustes gratilla, and the shrimp Litopenaeus stylirostris. Larvae of Holothuria fuscogilva and Tripneustes gratilla were the most sensitive for assessing sediment quality. Data mapping revealed high toxicity, up to 100 % mortality of larvae, in selected sites such as the Vaitepiha river mouth, Titaaviri, Atimaono in Tahiti Islans, as well as ‘Ōpūnohu Bay, Cook Bay, and Haapiti Bay in Moorea, and lake Maeva in Huahine. Despite not being chemically characterized, this toxicity is attributable to various sources of pollution, including agricultural, urban runoff and industrial effluents, as well as harbor and leisure activities. This study provides a significant contribution to the assessment of sediment quality in Society Islands, by identifying species that will provide essential predictive tools for adaptive management of tropical lagoons and identifying areas that showed high rates of developmental anomalies, requiring increased monitoring
MiCoReCa (Microbiome Community Resource Catalogue) - Towards Centralized Curation And Integration Of Microbiome Bioinformatics Resources
No full textThe rapid growth of microbiome research has led to the development of numerous bioinformatics tools and databases, but information about them remains fragmented across disparate, often outdated cataloging efforts, hindering resource discovery and utilization. To address this critical gap, the ELIXIR Microbiome Community proposes the development of MiCoReCa (Microbiome Community Resource Catalogue), a comprehensive, dynamic, open-access catalogue of microbiome-related bioinformatics resources (tools, workflows, training, standards, and databases). Leveraging our community's expertise, this initiative will utilize standardized ontologies like EDAM and cross-reference established platforms like bio.tools and WorkflowHub to create a centralized, findable inventory. A key feature is the community-driven process for identifying and curating missing ontological terms and metadata, ensuring MiCoReCa's accuracy and relevance in collaboration with partner platforms. Furthermore, the catalogue will integrate links to training materials from TeSS to support appropriate tool usage, and connect with OpenEBench for benchmarking capabilities. This project will not only provide a vital resource for the microbiome field, enhancing research efficiency and reproducibility, but will also establish a sustainable, adaptable infrastructure potentially applicable to other ELIXIR Communities. This effort represents a significant contribution by the ELIXIR Microbiome Community to streamline microbiome bioinformatics
Automorphismes de corps finis à partir des cycles d'isogénie.
No full textWe develop an explicit geometric construction of automorphisms of finite fields arising from isogeny cycles. Let k be a finite field, E/k an elliptic curve, and ℓ an integer coprime to char(k). Let h ⊆ End(E) be an ideal dividing (ℓ), and consider the corresponding torsion subgroupFrom the action of End(E) on E[h], we construct the splitting field K of the x-coordinates of points in E[h] and the associated Galois group Gal(K/k). This yields (End(E)/h) * → Gal(K/k) a group homomorphism.Nous développons une construction géométrique explicite des automorphismes des corps finis issus des cycles d'isogénie. Soit k un corps fini, E/k une courbe elliptique et ℓ un entier premier avec char(k). Soit h ⊆ End(E) un idéal divisant (ℓ), et considérons le sous-groupe de torsion correspondant À partir de l'action de End(E) sur E[h], nous construisons le corps de décomposition K des abscisses des points de E[h] et le groupe de Galois associé Gal(K/k). Il en résulte un homomorphisme de groupes (End(E)/h) * → Gal(K/k). </div
Multi-Omics Reprogramming Drives a Counterintuitive Reversal of Disease Susceptibility During Ageing
No full textInternational audienceAgeing is a progressive and irreversible biological process characterized by the deterioration of physiological functions and increased vulnerability to mortality. Although extensively studied in vertebrates, ageing in long-lived invertebrates remains comparatively unexplored. While ageing typically leads to greater susceptibility to infectious diseases, a striking and unexpected reversal was identified in oysters: older oysters exhibit markedly increased tolerance to the Pacific Oyster Mortality Syndrome (POMS), a panzootic disease primarily driven by the OsHV-1 herpesvirus and responsible for severe losses in global aquaculture. To investigate this counterintuitive pattern, we challenged oysters aged 4, 16, and 28 months from four biparental families and conducted an integrative multi-omics analysis, including epigenomics, transcriptomics, and metabolomics on the two families showing the strongest age-related increase in survival. Our results reveal that ageing in Magallana gigas is characterized by coordinated epigenetic, transcriptional, and metabolic reprogramming that reduces host permissiveness to POMS. We show that the epigenetic remodeling of key immune regulators (e.g., Toll-like receptors, MyD88) aligns with transcriptional rewiring of NF-κB and ubiquitin pathways, producing a finely tuned innate immune state marked by enhanced antiviral activity but reduced antibacterial responsiveness. We also identify age-related repression of mTOR signaling, likely promoting autophagy and improving viral control. These regulatory changes are tightly linked to metabolic adjustments, including reduced TCA cycle flux, remodeled nitrogen metabolism, and altered glutathione dynamics, which collectively support a stress-tolerant, energy-conserving phenotype. Together, our findings reveal a fundamental evolutionary trade-off: juveniles prioritize growth at the cost of viral susceptibility, whereas adults invest in cellular maintenance and antiviral preparedness
Reconstructing the geological evolution of small tropical volcanic islands: Insights from the study case of Moorea (French Polynesia)
No full textInternational audienceStudying extinct volcanic islands is critical to constrain the geological evolution of intra-plate volcanoes and shed light on related natural hazards. From new fieldwork, geomorphological and new K/Ar geochronological data, we revisited the main stages of growth and destruction of Moorea, a small and highly eroded tropical volcanic island in French Polynesia. We show that: (1) the southern part of the island comprises the remnants of a main former basaltic volcano that was active between ca 1.85 Ma and 1.70 Ma; (2) the northern flank of this early edifice was removed around 1.64 Ma by a main flank-collapse that produced debris-avalanche partly exposed on the ocean floor up to 30 km from the island shore; the sudden subsequent decompression was followed by (3) vigorous volcanic activity witnessed by widespread strombolian deposits including peridotite xenoliths; a second main volcanic edifice rapidly grew inside the collapse depression between 1.64 Ma and ca 1.58 Ma, (4) overflowed into adjacent valleys until 1.50 Ma and (5) was followed by less-voluminous sporadic lava eruptions until ca 1.35 Ma; late volcanic units (3-5) were erupted from vents along the E-W direction, and/or small parasitic cones around the rims of the collapse scar; related lava flows covered unconformably the weathered slopes of the older edifice and filled existing paleo-valleys; (6) subsequent erosion enlarged the former landslide scar and led to significant topographic inversion. Successive construction and destruction episodes on small volcanic islands like Moorea led to strong geometric imbrication of geological units, which has important societal implications, e.g., for volcanic aquifers management or land occupation.</div
From the abyss to efficiency: Optimizing Sea Water Air Conditioning (SWAC) for sustainable cooling
No full textInternational audienceAs global cooling demand grows, improving air conditioning efficiency while reducing its environmental impact is an urgent challenge. Sea Water Air Conditioning (SWAC) harnesses deep seawater as a renewable cooling source and offers a promising low-carbon alternative to conventional systems. This study presents a parametric sensitivity analysis and a multi-objective optimization of a large-scale SWAC installation in French Polynesia, using a numerical model validated by experimental data and coupled with a dynamic building simulation. Key design and operational parameters, such as seawater intake temperature, chilled water loop configuration, and heat exchanger effectiveness, are identified using the Morris method and optimized through a Non-dominated Sorting Genetic Algorithm. Results show that the global coefficient of performance can be increased from 24.7 up to 85.6, nearly 24 times higher than typical values for split-system air conditioners, while preserving comfort and adequate dehumidification. Raising the seawater intake temperature from 5 • C to 8 • C significantly reduces capital costs, resulting in major economic benefits: the Levelized Cost of Cooling decreases from 0.312 /kWh, the payback period shortens from 15 to 7 years, and the Net Present Value nearly doubles. These results highlight SWAC's potential as a high-efficiency, economically viable, and climate-resilient cooling solution. Furthermore, coupling SWAC with complementary systems such as OTEC could enhance resource utilization, reinforce its contribution to net-zero targets, and broaden its applicability in tropical and coastal regions
Assessing innovation readiness in European tourism and hospitality firms: Evidence from the European company survey
No full textInternational audienceTourism and hospitality (T&H) firms in Europe face mounting pressure to innovate amid rapid digitalization, globalization, and competition. This study examines the relative innovativeness of T&H firms compared to other sectors, using harmonized data from the 2019 European Company Survey (ECS) covering all EU countries. Innovation is assessed across three dimensions (product, process, and marketing) and by degree of novelty, distinguishing radical (new-to-market) from new-to-firm innovations, while also capturing underlying innovation readiness. Results show that, compared to other sectors, T&H firms are less likely to introduce market-new innovations, but display a strong propensity for incremental and adaptive innovation. Innovation outcomes are primarily shaped by enabling capabilities rather than structural firm characteristics, with ICT adoption, female leadership, strategies focused on quality and location emerging as key drivers. Findings also reveal intra-sectoral heterogeneity, highlighting the need for differentiated policies tailored to T&H subsectors. This study provides the first cross-sectoral, cross-national assessment of innovation in European T&H SMEs, helping close an empirical gap and foster innovation and competitiveness in the tourism economy
Aménagements commerciaux dans les collectivités du Pacifique Sud : un contrôle ex ante générateur de gaspillage de ressources
No full textInternational audienceL'Autorité polynésienne de la concurrence a récemment rendu une décision d'aménagement commercial, ce qui représente plus de la moitié de son activité décisionnelle. La très faible envergure de l'opération, ainsi que le délai particulièrement long pour déclarer la complétude du dossier de notification, viennent illustrer une nouvelle fois l'inefficacité de ces contrôles ex ante dans les collectivités du Pacifique Sud