HAL Portal UPPA (University of Pau and the Pays de l'Adour)
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Développement d'un framework de suivi et d'évaluation de l'impact à travers un data warehouse sémantique pour les méta-organisations
No full textInternational audienceCe travail de recherche vise à développer un cadre pour les méta-organisations (notamment les alliances d'universités européennes) pour surveiller et évaluer leur impact sur la société en utilisant des solutions données. Les alliances d'universités européennes, telles que celles créées dans le cadre de l'initiative européenne des universités, nécessitent des outils et des méthodologies spécifiques pour évaluer leur impact, qui dépasse celui des organisations individuelles. Ce cadre devra prendre en compte la complexité des organisations interconnectées et la nécessité de flexibilité pour répondre aux besoins spécifiques de chaque organisation membre
Environmental DNA illuminates the darkness of mesophotic assemblages of fishes from West Indian Ocean
No full textInternational audienceThe advent of environmental DNA (eDNA) represents a pivotal advancement in probing mesophotic communities, offering a non-intrusive avenue for studying marine biodiversity at greater depths. Using this approach, we characterized and compared the mesophotic reef fish assemblages of two West Indian Ocean islands, Mayotte and La Réunion, which are characterized by different geo-morphological contexts. The sequences obtained were assigned taxonomically and grouped into molecular operational taxonomic units to perform richness and beta diversity analyses. The functional diversity of the assemblages was assessed using five traits, enabling each sequence to be assigned to a functional entity corresponding to a specific trait combination. On both islands, the fish assemblages exhibited a comparable level of taxonomic and functional richness, consisting mainly of piscivorous and planktivorous fishes. These assemblages were primarily composed of families such as Serranidae, consistent with expectations for the mesophotic zone. However, beta diversity analyses revealed that the two islands exhibited different taxonomic and functional structures. For example, La Réunion was characterized by a greater importance of the Muraenidae, while Mayotte displayed a higher representation of families strongly associated with coral reefs (e.g., Zanclidae or Malacanthidae). These results suggest that depth-related forcing constrains fish assemblages to some extent, but that differences in structure remains determined by other, more local factors, likely linked to the geo-morphological contexts of the islands and their habitats. This study also revealed that eDNA is a promising method for studying difficult-to-observe taxa, such as moray eels or lanternfish, and may also be relevant for monitoring species depth ranges. Overall, results highlighted the “local scale”, “functionally integrative” and “temporally integrative” characteristics of eDNA for studying mesophotic reef fish assemblages. However, this study also highlights the limitations of reference DNA databases, pointing to future prospects for fully exploiting the potential of eDNA approaches in the mesophotic zones of the Indian Ocean
Structure and ion conducting properties of mixed-alkali Na<sub>3– x</sub>Li<sub> x</sub>InCl<sub>6</sub> solid electrolytes
No full textInternational audienceBall-milled and annealed Na3– xLi xInCl6 samples exhibit a solubility limit at x = 0.6 and a monoclinic-to-trigonal phase transition. Neutron diffraction and impedance spectroscopy suggest a connected Li network with enhanced ionic conductivity
Influence of polypropylene fibers on thermal-induced permeability changes in concrete
No full textInternational audienceDuring a fire, concrete structures experience rapid heating leading to thermal instability (spalling), compromising load-bearing capacity by reducing the concrete's cross-section or exposing steel reinforcement to flames. Polypropylene fibers are recognized for their effectiveness in mitigating instability risks. The study aims to enhance understanding of fiber's behaviour during heating to optimize their dosage and limit adverse effects on fresh concrete. Four concretes have been studied with calcareous gravels and mortar aggregates, with and without polypropylene fibers. Two samples of each concrete type were tested: C1-0 (calcareous aggregate), C1-18/32(0.5) (calcareous aggregate with fibers), C1MA (mortar aggregate), and C1MA-18/32(0.5) (mortar aggregate with fibers). The use of mortar aggregates allows us to investigate the influence of thermal mismatch and to better understand the interaction between several phenomena: cracking due to thermal mismatch and porosity and cracking due to fiber melting. Controlled heating from 80°C to 450°C at a rate of 2°/min was conducted, followed by a 3-hour stabilization before radial permeability testing. Results indicate a temperature-dependent increase in intrinsic permeability across all concrete types, with mortar aggregates showing lower permeability values. Mortar aggregate induces minimal thermal mismatch compared to calcareous aggregate, owing to its similar expansion and shrinkage characteristics to cement paste. This reduced thermal mismatch results in fewer cracks when exposed to elevated temperatures, further contributing to the lower permeability of concretes containing mortar aggregate. In contrast, fiber-reinforced concretes exhibited higher permeability, primarily due to the melting and expansion of polypropylene fibers around 170°C. Overall, these findings suggest that the mechanism that increases permeability and reduces spalling is primarily linked to the addition of fibers. While polypropylene fibers are effective in enhancing concrete's permeability and minimizing thermal instability, the thermal expansion of aggregates also has a high influence in this risk. Further research would explore the effects of mechanical loading on the intrinsic permeability of these concrete types and investigate polypropylene fibers with varying geometries and dosages to compare results with the current findings.</div
Applications of coastal videometry within a multi-scale coastal flooding assessment framework - Basque Coast
No full textInternational audienceThe Basque Coast video-monitoring network provides high-frequency and continuous images of nearshore areas along the Basque Coast. The coastal flooding and morphological parameters are collected from the network at regional scale. The use of these parameters for a multi-scale coastal flooding assessment framework is presented
Spéciation du cadmium sanguin pour évaluer l'exposition au cadmium des travailleurs.
No full textCadmium is a toxic metal that can cause adverse health effects such as kidney, bone, and liver damage, even at very low concentrations. By reason of its proven carcinogenicity in humans, it is classified as a Group 1 carcinogen by the IARC. Despite usage restrictions, cadmium remains particularly prevalent in occupational environments. Therefore, assessing workers' exposure to low doses is essential and relies on appropriate biological monitoring. This PhD thesis focuses on the development of specific analysis methods of cadmium in blood as a relevant biomarker of occupational exposure. The pharmacokinetics of cadmium in blood highlights two phases of elimination, depending on its different physicochemical forms: a short one (less than three months) and a long one (over ten years). Both were studied from two types of blood-fraction analysis (erythrocytes and plasma). In addition, cadmium speciation in plasma was also implemented to differentiate cadmium-protein complexes. These methods were adjusted so as to work on micro volumes. Initially, erythrocyte analysis using single-cell approaches was validated, and the performance levels of scICP-MS and scICP-MS/MS were compared. These techniques proved precise and sensitive, particularly in scICP-MS/MS mode, thanks to optimized interference management. The latter also demonstrated high efficiency for analyzing blood micro volumes (<0.1 µL). Subsequently, the quantification of metalloproteins in plasma was carried out using HPLC(SEC)-ICP-MS/MS. This approach was validated with plasma samples supplemented with cadmium and relevant metalloproteins (albumin and metallothioneins), as well as by quantifying naturally-occurring isotopes in blood. Following these developments, an analytical protocol applicable to a few microliters of blood was proposed. Finally, these methods were tested in real conditions and compared with conventional analyses conducted during an occupational biological-monitoring campaign. The results showed overall consistency between the specific and traditional analyses performed. Generally, cadmium was primarily found in erythrocytes and complexed with albumin in plasma. However, low exposure levels did not allow the quantification of metallothioneins and intra-erythrocyte cadmium by single-cell ICP-MS. In conclusion, this work proposes innovative and sensitive methods for cadmium quantification in erythrocytes and cadmium speciation in plasma. These methods, applicable to the biological monitoring of exposed workers, will also contribute to a better understanding of cadmium distribution and metabolism in the human body. Furthermore, these methods will be easily deployed for the determination of other metals of interest.Le cadmium est un métal toxique, même à très faibles concentrations, qui peut engendrer des effets néfastes sur la santé, tels que des atteintes rénales, osseuses et hépatiques. Par ailleurs, classé en catégorie 1 par le CIRC en raison de sa cancérogénicité avérée chez l’Homme, il reste toutefois encore particulièrement présent en milieu professionnel malgré des restrictions d’usage. L’évaluation des expositions des travailleurs est donc essentielle et doit reposer sur un suivi biologique adapté. Ce travail de thèse vise à développer des méthodes d’analyse spécifiques dans le sang pour un suivi biologique pertinent. En effet, le sang, matrice centrale de l’organisme, possède deux composantes temporelles d’élimination du cadmium, relatives aux différentes formes physico-chimiques : une composante à long terme (plus de dix ans) et une à court terme (moins de trois mois). L’étude de ces deux composantes a été réalisée par des analyses spécifiques des fractions sanguines érythrocytaire et plasmatique. Une spéciation du cadmium dans le plasma a notamment été mise en œuvre afin de différencier les complexes cadmium-métalloprotéines. Par ailleurs, les méthodes ont été envisagées afin de pouvoir réaliser l’analyse sur des micro-prélèvements. Dans un premier temps, l’analyse des érythrocytes par single cell a été validée et les performances des modes scICP-MS et scICP-MS/MS ont été comparées. Ces techniques se sont révélées précises et sensibles, notamment le mode scICP-MS/MS, grâce à une gestion optimisée des interférences. La méthode développée a également montré une grande efficacité pour analyser de très faibles volumes de sang (<0,1 µL). Dans un second temps, la quantification des métalloprotéines dans le plasma a été réalisée par HPLC(SEC)-ICP-MS/MS. Cette approche a été validée sur des échantillons de plasma dopés en cadmium et en métalloprotéines d’intérêt (albumine et métallothionéines), ainsi qu’en quantifiant des isotopes naturellement présents dans le sang. À l’issue de ces développements, un protocole d’analyse applicable à des volumes de quelques microlitres de sang a été proposé. Finalement, ces nouvelles méthodes ont été testées en conditions réelles et comparées aux analyses conventionnelles déployées lors d’une campagne de suivi biologique en entreprise. Les résultats ont montré une cohérence globale entre les différentes analyses réalisées, spécifiques et classiques. D’une manière générale, le cadmium a été majoritairement retrouvé dans les érythrocytes et complexé à l’albumine dans le plasma. En revanche, les niveaux d’exposition faibles n’ont pas permis de quantifier les métallothionéines et le cadmium intra-érythrocytaire par single cell ICP-MS. En conclusion, ce travail propose des méthodes innovantes et sensibles pour le dosage du cadmium dans les érythrocytes et la spéciation dans le plasma. Ces méthodes, applicables au suivi biologique des travailleurs exposés, contribueront par ailleurs à une meilleure compréhension de la distribution et du métabolisme du cadmium dans l’organisme. En outre, elles pourront aisément être déployées pour la détermination d’autres métaux d’intérêts
Physical Education for a Sustainable Future: Merging Promotion of Health Through Physical Literacy With Global Environmental Responsibility
No full textInternational audienceThis article examines how redefining health through the perspectives of One Health, EcoHealth and Planetary Health can enrich Physical Education (PE) by advancing both health and environmental sustainability. While PE and health education are often treated as separate subjects, most PE curricula worldwide emphasise the promotion of an active lifestyle as a key component of health education through PE. This promotion of an active lifestyle is central to the concept of physical literacy (PL), which is a fundamental aspect of quality PE according to UNESCO (2015). This article focuses on how PE, contributing to health education through the promotion of PL, can evolve to incorporate sustainability goals through the recent new definitions of approaches to health. One Health approach underscores the interconnections between human, animal and environmental health, expanding PL to address zoonotic diseases and ecological impacts. EcoHealth highlights the sustainability of ecosystems, promoting PE activities that (re)connect humans with the more-than-human worlds without causing environmental harm. Planetary Health takes a global perspective, encouraging sustainable physical activities that reduce ecological footprints, such as cycling and walking. By integrating these holistic frameworks, PE can nurture not only individual health outcomes but also environmental stewardship and global health awareness. This shift seeks to educate individuals about their PL, but also their responsibility in preserving ecosystems and the planet, fostering a more sustainable and environmentally aware generation through PE
Territoires poétiques dans l'œuvre de Virginia Pesemapeo Bordeleau
No full textInternational audienceCette conférence proposée dans le cadre d'un séminaire du CRILCQ abordait la manière dont l'artiste multidisciplinaire eeyou Virginia Pesemapeo Bordeleau rend possible l'expression d'un mode de relation à l'environnement et au territoire différent de celui imposé par la pensée coloniale