HAL Collection UNC (Univ. de la Nouvelle Calédonie)
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Genetic Relatedness and Parentage Analysis as a Framework to Enhance Local Conservation Strategies for Marine Species
No full textInternational audienceConservation of marine species faces specific challenges, especially considering the environmental factors and cryptic behaviors that affect organismal dispersal. In the context of conservation genetics, microsatellite markers have been successfully applied in population genetics to assess genetic differentiation and delineate population clusters, helping to identify broader scale conservation needs. Here, we tested the relevance of using microsatellite markers to perform parentage analysis with very little information on a marine sessile organism to inform spatial conservation efforts. Specifically, we investigated the genetic structure of Atrina vexillum, a large marine bivalve, sampled in the lagoon of Bora-Bora. Our primary objective was to sample a significant portion of the population with a stratified underwater survey, which led to the sampling of 1389 individuals, estimated to represent ~80% of the total population. We then screened 30 microsatellite loci to compute a relatedness matrix and assess genetic relationships among individuals. Based on pairwise relatedness values, we computed a UPGMA hierarchical clustering to construct family groups and compared the results with a maximum-likelihood-based parentage analysis implemented in COLONY. In parallel, we also looked for genetic structure using Bayesian clustering with STRUCTURE. We then investigated spatial patterns of genetic relatedness, testing correlations with geographic distances. The distribution of relatedness values indicated a relatively even contribution to reproduction among sampled individuals. Although no population structure was detected using the Bayesian clustering algorithm, we identified multiple family groups, some comprising up to 19 individuals. Spatial analyses showed no significant correlation between genetic relatedness and proximity, except among closely related individuals, who tended to be found in close proximity. Our findings highlight the value of the relatedness-based approach to identify genetic connectivity and reproductive behavior. In A. vexillum, this approach demonstrates the importance of protecting high-density areas where settlement occurs, even though no spatial genetic structure was found within the lagoon
« L'écriture de Déwé Gorodé: la circulation comme fondation d'une esthétique littéraire kanak »
No full textInternational audienceDe la publication de Sous les cendres des conques (1985) à celle de son roman Tâdo, Tâdo, wéé ! (2012), Déwé Gorodé construit une géopolitique de la décolonisation, fondée sur une esthétique de la circulation. Ancrée dans son parcours de militante et en écho aux revendications politiques kanak, son œuvre dessine une cartographie de l’émancipation. Cette cartographie est rythmée par des « instants autobiographiques » où l'autrice retrace ses déplacements et ses rencontres, chaque lieu devenant un point nodal d'une poétique de fraternité politique. Des villes comme Alger, Tunis, New York, Abidjan, jusqu'à Nouméa et sa région natale Pwäräiriwa, Gorodé tisse un réseau de relations poétiques motivées par l’expérience coloniale partagée. Chaque espace devient le point de convergence d'une poétique de la fraternité politique, fondée sur l'expérience coloniale partagée. Par ailleurs, ces circulations ne sont pas seulement géographiques, mais aussi littéraires : le monde kanak s'inscrit dans un réseau d'échanges où la solidarité et la décolonisation sont pensées de manière globale. Ainsi, le dévoilement du monde kanak se réalise à travers un réseau d'échanges et de solidarités, ancrant cette littérature dans une dynamique mondialisée de la décolonisation. Cette communication se propose d’analyser comment l’œuvre de Déwé Gorodé, à travers l'esthétique de la circulation, élabore une vision décoloniale fondatrice, fondation d’une littérature kanak ouverte et en mouvement
Coral recruitment in mesophotic coral ecosystems is lower and taxonomically distinct from shallow environments at Reunion Island, southwestern Indian Ocean
No full textInternational audienceCoral recruitment is an essential demographic mechanism that underpins the community structure and dynamics of coral reefs and facilitates post-disturbance coral recovery. However, information on coral recruitment patterns in mesophotic coral ecosystems (MCEs) is globally scarce, and no study describes patterns in the lower mesophotic zone (> 60 m depth). We quantified spatial variability in coral recruitment at shallow (15 m), upper (45 m) and lower (75 m) mesophotic depths across three contrasted locations (nine stations) around Reunion Island in the southwestern Indian Ocean. This study, the first to assess coral recruitment patterns on lower mesophotic habitats, highlighted a marked decline in recruitment rate in MCEs consistently across locations. Recruit composition varied significantly with depth, with Pocilloporidae dominating shallow habitats, while lower MCEs exclusively harbored “other” coral family recruits (i.e., other than Acroporidae, Pocilloporidae and Poritidae). Coral recruitment rate on tile surface orientation varied significantly with depth, with an overall higher proportion of recruits recorded on top surfaces at lower mesophotic depths. The abundance of Pocilloporidae recruits was positively correlated with confamilial adult coral cover, suggesting stock-recruitment or recruitment-limitation models for the dynamic of dominant shallow corals over a broad depth gradient. Upper MCEs could constitute substantial refuges for Pocilloporidae corals, while lower MCEs are of paramount importance for “other” coral families. Interannual surveys are necessary to better understand the spatiotemporal variability of coral recruitment in shallow habitats and MCEs and the driving forces of early post-settlement processes
Maritime piracy bibliometric analysis: A literature overview and map review
No full textInternational audienceAbstract Maritime piracy represents a significant international challenge, impacting both economic stability and political dynamics. Researchers from diverse disciplines have been drawn to this multifaceted issue, each aiming to understand and address different aspects of piracy’s impact and implications. This study offers a comprehensive overview of maritime piracy research based on bibliographic analysis. Its objective is threefold. First, to delineate the key domains of inquiry within maritime piracy research. These domains encompass a wide range of topics, including the socio-economic drivers of piracy, the legal frameworks governing maritime security, and computer science to analyse piracy acts. Second, to identify major contributions in the field, recognising seminal works, influential authors and significant findings related to maritime piracy. Lastly, to discern emerging research trends within maritime piracy, and to identify novel areas of inquiry, innovative methodologies and promising avenues for future exploration. Furthermore, the most popular datasets from these studies that include relevant information are presented in this work
William Gilmore Simms’ ‘The Brothers of the Coast’ and the Use of the Pirate Figure
No full textInternational audienceThis article reconsiders William Gilmore Simms’s The Brothers of the Coast through the lens of oceanic studies, arguing that Simms’s unfinished postbellum pirate narrative has long been misread through a landlocked, Southern-centered interpretive tradition. Rather than treating Simms’s maritime fiction as a mere allegory of regional or postbellum anxiety, the article approaches the ocean as an autonomous space of meaning—one that generates alternative forms of community, identity, and political imagination.Building on Margaret Cohen’s diagnosis of literary hydrophasia—the critical tendency to overlook or marginalize the maritime dimension even when it is central to a text—and drawing on work by Rediker, Linebaugh, Blum, and Chambers, the study shows that Simms constructs Nassau as a radically fluid, multiethnic, and extraterritorial space. This pirate enclave functions as an insurgent formation that resists national sovereignty, racial fixity, and stable social hierarchies. Within this framework, the pirate emerges as a flexible and destabilizing figure who complicates dominant models of Southern masculinity at a moment when the planter-gentleman ideal appeared increasingly ineffective in the aftermath of the Civil War. Through the liquefaction of names, identities, and gender roles, Simms imagines a social order structured by mobility, heterogeneity, and indeterminacy rather than by territorial or national coherence.At the same time, the article highlights the narrative’s internal efforts to reimpose order—most notably through Steel Cap’s utopian political project—which are ultimately exposed as untenable attempts to discipline a community fundamentally shaped by movement and contingency. By taking the seascape seriously on its own terms, this study argues that The Brothers of the Coast articulates an insurgent oceanic aesthetic that challenges terracentric critical frameworks and resituates Simms within a broader Atlantic and maritime literary history. In doing so, it identifies the pirate tale as a privileged site for rethinking the boundaries of nation, masculinity, and citizenship in the postbellum United States.Cet article propose une relecture de The Brothers of the Coast de William Gilmore Simms à partir des études océaniques, en montrant que ce récit inachevé de pirates, écrit dans l’après-guerre de Sécession, a été durablement interprété à travers une grille terracentrique et sudiste. Plutôt que d’envisager la fiction maritime de Simms comme une simple allégorie des anxiétés régionales ou postbellum, l’étude aborde l’océan comme un espace autonome de production de sens, capable de générer des formes alternatives de communauté, d’identité et d’imaginaire politique.S’appuyant sur l’analyse par Margaret Cohen de l’hydrophasia critique — c’est-à-dire la tendance des études littéraires à invisibiliser ou marginaliser la dimension maritime, même lorsqu’elle est centrale — ainsi que sur les travaux de Rediker, Linebaugh, Blum et Chambers, l’article montre que Simms construit Nassau comme un espace radicalement fluide, multiethnique et extraterritorial. Cette enclave pirate fonctionne comme une formation insurgée qui résiste aux frontières nationales, aux hiérarchies raciales et aux catégories sociales stabilisées. Dans ce cadre, la figure du pirate apparaît comme une force mobile et déstabilisatrice, qui met en crise les modèles dominants de la masculinité sudiste à un moment où l’idéal du planteur-gentleman se révèle de plus en plus inopérant dans le monde post–guerre de Sécession. Par la fluidification des noms, des identités et des rôles de genre, Simms imagine un ordre social fondé sur la mobilité, l’hétérogénéité et l’indétermination plutôt que sur la cohérence territoriale ou nationale.L’article montre toutefois que les tentatives internes au récit visant à réimposer un ordre stable — notamment à travers le projet politique utopique de Steel Cap — sont présentées comme vouées à l’échec, car incompatibles avec une communauté façonnée par le mouvement et la contingence. En prenant au sérieux le paysage maritime pour lui-même, cette étude soutient que The Brothers of the Coast élabore une esthétique océanique insurgée, qui remet en cause les lectures terracentriques et permet de recontextualiser Simms dans une histoire littéraire atlantique et maritime plus large. Le récit de pirates apparaît ainsi comme un lieu privilégié pour interroger et reconfigurer les frontières de la nation, de la masculinité et de la citoyenneté dans les États-Unis de l’après-guerre
ANNUAL FRENCH WORKSHOP ON WELL-BEING IN ASTROPHYSICS : CREATING A POSITIVE AND INCLUSIVE WORK ENVIRONMENT
No full textInternational audienceDiversity is very important within an organisation because it fosters creativity and innovation, but it can occasionally lead to difficulties in understanding others, bias towards colleagues or even discrimination. Here we provide a summary of the ideas discussed during the 2025 French Well-being in Astrophysics workshop held at the French National astronomy meeting, which can help promote a positive and inclusive working environment, regardless of age, experience, origin, religion, gender, sexual orientation or disability. These included better understanding colleagues and current problems through a national survey, methods and feedback from mentoring programmes and ideas for preventing conflict
ClimBurst: A Dynamic Visualization Tool to Display Climatological Anomalies over Time and Space
No full textInternational audienceDetecting abnormal climate events across temporal and spatial scales is crucial to the understanding of local and regional climate trends. This demonstration introduces ClimBurst, a dynamic tool to detect climate bursts, which are unusually high or low values of one or more climate variables over some time interval. ClimBurst detects bursts without prior assumptions about their temporal duration. The demonstration will allow users to interact directly with our system to see both a summary showing the presence/absence of bursts over a user-specified year and spatial range. The demonstration will also allow users to perform time-travel queries to see how bursts propagate over space and time
Perspectives juridiques de Chine
No full textInternational audienceCette étude analyse la gestion chinoise de la pandémie de Covid-19 sous l’angle des libertés et du droit comparé. Elle met en évidence l’ontologie juridique chinoise, fondée sur le collectivisme et la préservation de l’unité nationale, qui justifie des restrictions importantes aux droits individuels. Le système révèle un dualisme entre droit étatique et règles officieuses, renforcé par l’influence confucéenne et le rôle central du Parti communiste. Les mesures sanitaires, bien que juridiquement encadrées, ont entraîné des atteintes à la vie privée, à la liberté d’expression et de circulation, sans contrôle indépendant. Cette approche illustre la tension entre universalité des droits et pluralité des modèles juridiques
Inference of couplings between variables of a given system using causal wavelets, causal information, equations reconstruction, and other techniques
No full textInternational audienceTo infer directional couplings from variables is a difficult problem in dynamical systems, especially when its variables are taken from the real world. Many approaches have been developed to infer such couplings directly from observational time series. The objective of the present study is to investigate the capabilities of a set of techniques in test situations where the dynamics are governed by either fully deterministic (ordinary differential) equations or partially deterministic equations (the same ones with a stochastic perturbation added, the deterministic part remaining dominant). The studied system is based on two three-dimensional chaotic subsystems with very different dynamics, but similar structure, considering various couplings between them (none, unidirectional, bidirectional). One system is dissipative, and the other one is conservative. The time evolution produced by their variables is clearly correlated with one system, almost totally decorrelated with the other one. The following techniques, some of which are introduced in this study, are considered: simple/causal correlation, mutual/causal information, Granger causality index, cross/causal wavelet coherence, bivariate global modeling, and equation reconstruction techniques. All the techniques are evaluated based on their ability to detect direct and indirect causal relationships. Most of them prove poorly capable of detecting direct couplings and are not really robust in the contexts with low variable correlation, external weak couplings, and stochastic perturbations. Applied to the current problems, the bivariate modeling and the equation reconstruction techniques, both based on a global modeling technique, appear to be the most effective approaches to infer causality. The detection of weak bidirectional couplings appears particularly challenging under noisy conditions. Causal detection is tested on a set of groundwater level observational time series, revealing deterministic but complex couplings between three sub-basins of the Se San River basin (Central Highlands, Vietnam)