HAL Portal UPF (Université de la Polynésie française)
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Multilingualism in the Social Ecology of French Polynesia: Bridging the gap between additional language learning research and classroom practices
No full textInternational audienceThis work provides an overview of research activities carried out on English as an additional language (EAL) and content and language integrated learning (CLIL) teaching practices in the French Polynesian elementary school context. Transdisciplinary research on EAL was conducted in the framework of the plurilingual landscape in French Polynesian social ecology. Extended classroom corpora were gathered on EAL teaching across the five archipelagos of French Polynesia (2012-2018), aimed at bridging the gap between language-learning research and teaching practice and thereby contributing to the improvement of existing language pedagogy. These studies primarily used discourse analysis methodologies focused on both the learner and the teacher. Research outcomes were communicated during teacher education sessions to build awareness of EAL pedagogies in novice, pre-service and practising teachers in the French Polynesian context. Areas addressed in these studies included learner involvement, classroom interaction types, and teacher and peer mediation strategies
La reconnaissance faciale aux abords des lycées: quelle faisabilité juridique ?
No full textLe club des juristes - l'actualité sous le prisme du droitAu lendemain de l'attentat perpétré dans un lycée d'Arras, Laurent Wauquiez appelle de ses voeux un changement de la loi afin de pouvoir tester la reconnaissance faciale aux abords des lycées. Les partisans de cette mesure expliquent en restreindre l'application aux individus suivis pour radicalisation terroriste. Est-ce juridiquement possible ? Cet article présente les fondements juridiques permettant de répondre à cette question
Presentation of specific aspect of national reports that are relevant to resolutions : Part II: Predictive justice - French report
No full textInternational audienc
Discussion about suitable applications for biodegradable plastics regarding their sources, uses and end of life
No full textInternational audienceThis opinion paper offers a scientific view on the current debate of the place of biodegradable plastics as part of the solution to deal with the growing plastic pollution in the world's soil, aquatic, and marine compartments. Based on the current scientific literature, we focus on the current limits to prove plastic biodegradability and to assess the toxicity of commercially used biobased and biodegradable plastics in natural environments. We also discuss the relevance of biodegradable plastics for selected applications with respect to their use and end of life. In particular, we underlined that there is no universal biodegradability of plastics in any ecosystem, that considering the environment as a waste treatment system is not acceptable, and that the use of compostable plastics requires adaptation of existing organic waste collection and treatment channels
Reconstructing the thermal history of fish juveniles using stable oxygen isotope analysis of otoliths
No full textInternational audienceIntroduction: Characterizing the thermal habitat of fish is key to understanding their ecological requirements in order to make appropriate management plans for the preservation of fish populations in the context of climate change. Little is known about the thermal habitat of the early life stages of fish (larvae and juveniles), as most methods have been designed for large, easily handled individuals. In particular, the study of otoliths holds great promise for unveiling the early thermal history of fish, although it is challenging to implement due to the very small size of the biological material. Methods: The stable oxygen isotope content (δ 18 O) of biogenic carbonates (such as otoliths) can be used to reconstruct the life temperature of fish individuals. However, relationships between δ 18 O of otoliths and ambient temperature are scarce and mainly developed for commercial species. In this study, we assessed the δ 18 O of juvenile European chub (Squalius cephalus, Linnaeus 1758) living in a section of the lower Rhône River in France. Results: The δ 18 O of otoliths showed significant relationship with ambient temperature [δ 18 O oto(VPDB)-δ 18 O w(VPDB) = 33.391-0.2641 * T (°C)], and the relationship between temperature and the fractionation factor (α) was 1,000 ln α = −43.472 + 21.205 [1,000/T(K)]. Discussion: As expected, back-calculated temperatures from these equations were in much better agreement with the measured in situ temperatures than previously published equations. This equation is the first to be developed for leuciscid fish in Europe and the second in the world
Disparate genetic divergence patterns in three corals across a pan-Pacific environmental gradient highlight species-specific adaptation
No full textInternational audienceTropical coral reefs are among the most affected ecosystems by climate change and face increasing loss in the coming decades. Effective conservation strategies that maximize ecosystem resilience must be informed by the accurate characterization of extant genetic diversity and population structure together with an understanding of the adaptive potential of keystone species. Here we analyzed samples from the Tara Pacific Expedition (2016-2018) that completed an 18,000 km longitudinal transect of the Pacific Ocean sampling three widespread corals-Pocillopora meandrina, Porites lobata, and Millepora cf. platyphylla-across 33 sites from 11 islands. Using deep metagenomic sequencing of 269 colonies in conjunction with morphological analyses and climate variability data, we can show that despite a targeted sampling the transect encompasses multiple cryptic species. These species exhibit disparate biogeographic patterns and, most importantly, distinct evolutionary patterns in identical environmental regimes. Our findings demonstrate on a basin scale that evolutionary trajectories are species-specific and can only in part be predicted from the environment. This highlights that conservation strategies must integrate multi-species investigations to discern the distinct genomic footprints shaped by selection as well as the genetic potential for adaptive change
Les enseignant(e)s de la Martinique en période de confinement : la continuité pédagogique en question
No full textInternational audienceThis paper presents the results for a study on the lives, perceptions, and attitudes of teachers in the primary and secondary school systems in the Martinique administrative region, when put in lock-down. Data was gathered on line between March and April 2020, with a set of 855 respondents, in order to know of and measure their degree of digital integration, as well as study their domestic and professional conditions during the covid-19 epidemic. The results show that the pedagogical continuity strategies put in place by the government and by regional administrations during the crisis engendered extra work and much dissatisfaction among the island’s teachers. Furthermore, these strategies reached their pedagogical goals only partially and did not resolve the lack of technical means and digital resources (the digital divide) which overseas teachers suffer from.Cet article présente les résultats d’une étude sur le vécu, les perceptions et les attitudes des enseignants des premier et second degrés de l’académie de la Martinique en situation de confinement. L’enquête s’est réalisée en ligne, entre mars et avril 2020, sur un échantillon de 855 répondants, avec l’objectif de connaître et mesurer leur niveau d’intégration numérique, ainsi que les conditions domestiques et professionnelles pendant l’épidémie de covid-19. Les résultats obtenus montrent que les stratégies de continuité pédagogique mises en place par le gouvernement et les administrations régionales pour faire face à la crise ont engendré une surcharge de travail et un haut niveau d’insatisfaction chez les enseignants de l’île. De plus, ces stratégies n’ont atteint que partiellement leurs objectifs éducatifs et n’ont pu résoudre le manque de moyens techniques et ressources numériques (le digital divide) dont souffrent en particulier les enseignants des outre-mer
On the Validation of Gibbs Algorithms: Training Datasets, Test Datasets and their Aggregation
No full textInternational audienceThe dependence on training data of the Gibbs algorithm (GA) is analytically characterized. By adopting the expected empirical risk as the performance metric, the sensitivity of the GA is obtained in closed-form. In this case, sensitivity is the performance difference with respect to an arbitrary alternative algorithm. This description enables the development of explicit expressions involving the training errors and test errors of GAs trained with different datasets. Using these tools, dataset aggregation is studied and different figures of merit to evaluate the generalization capabilities of GAs are introduced. For particular sizes of such datasets and parameters of the GAs, a connection between Jeffrey's divergence, training and test errors is established
What are the toxicity thresholds of chemical pollutants for tropical reef-building corals? A systematic review
No full textInternational audienceBackground: Tropical coral reefs cover only ca. 0.1% of the Earth’s surface but harbour exceptional marine biodiversity and provide vital ecosystem services to millions of people living nearby. They are currently threatened by global (e.g. climate change) and local (e.g. chemical pollution) stressors that interact in multiple ways. While global stressors cannot be mitigated by local actions alone, local stressors can be reduced through ecosystem management. Here, we aimed to systematically review experimental studies assessing the toxicity of chemical pollutants to tropical reef-building corals to generate accessible and usable knowledge and data that can be used to calculate measurement endpoints in ecological risk assessment. From the quantitative estimates of effects, we determined toxicity thresholds as the highest exposures tested at which no statistically significant adverse effects were observed, and we compared them to regulatory predicted no effect concentrations for the protection of marine organisms, to assess whether these reference values are indeed protective of corals. Methods: The evidence was taken from a systematic map of the impacts of chemicals arising from human activity on tropical reef-building corals published in 2021. All studies in the map database corresponding to the knowledge cluster “Evidence on the ecotoxicological effects of chemicals on corals” were selected. To identify subsequently published literature, the search was updated using a subset of the search string used for the systematic map. Titles, abstracts and full-texts were screened according to the criteria defining the selected cluster of the map. Because the eligibility criteria for the systematic review are narrower than the criteria used to define the cluster in the systematic map, additional screening was performed. Studies included were critically appraised and each study was rated as low, unclear, medium, or high risk of bias. Data were extracted from the studies and synthesised according to a strategy dependent on the type of exposure and outcome. Review findings: The systematic review reports the known effects of chemical exposures on corals from 847 studies corresponding to 181 articles. A total of 697 studies (161 articles) were included in the quantitative synthesis and 150 studies (50 articles) in the narrative synthesis of the findings. The quantitative synthesis records the effects of 2706 exposure concentrations-durations of 164 chemicals or mixtures of chemicals, and identifies 105 toxicity thresholds corresponding to 56 chemicals or mixtures of chemicals. When toxicity thresholds were compared to reference values set for the protection of marine organisms by environmental agencies, the reference values appear to be protective of corals for all but three chemicals assessed: the metal copper and the pesticides diuron and irgarol 1051. Conclusions: This open-access database of known ecotoxicological effects of chemical exposures on corals can assist managers in the ecological risk assessment of chemicals, by allowing easy determination of various ecotoxicological thresholds. Several limitations of the toxicity tests synthesised here were noted (in particular the lack of measurement of effective concentrations for more than half of the studies). Overall, most of the currently available data on coral toxicity should be replicated independently and extended to corals from less studied geographical regions and functional groups