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Direct and indirect effects of pesticide exposure on the gut microbiota of a farmland raptor
No full textInternational audienceRecent studies in humans have shown that certain pesticides could affect the composition and functions of thegut microbiota, an essential modulator of vertebrate physiology, leading to potential dysbiosis. However, thisrelationship remains largely unknown in wild birds despite the implications of pesticides in the current decline offarmland species. The present study sought to fill this gap by providing data on the association between pesticideconcentrations in blood and gut microbiota characteristics in relation to individual traits in a farmland raptor,the Montagu’s harrier (Circus pygargus). Results showed that females with higher body condition and higherpesticide load exhibited greater gut bacterial richness and diversity, while the relationship was opposite in maleswith higher body condition. In terms of taxonomic composition, Proteobacteria emerged as the dominant phylumacross all nestlings. Differences in the abundance of specific phyla and genera were observed according to pesticide load, with higher levels of Bacteroidota and Leifsonia, but lower levels of Bulkholderia, in nestlings withhigher pesticide concentrations in their blood. This study highlights differences in microbiota and contaminationby several pesticides according to the phenotypic characteristics of a wild raptor, and shows that farmland birdscan represent relevant biosentinels for assessing the health/proper functioning of ecosystems (One Healthapproach)
3ConFA: A Robust Feature Aggregation Framework for High-dimensional Data Optimization
No full textInternational audienceHigh-dimensional datasets pose significant challenges in machine learning, including overfitting, increased computational complexity, and reduced model interpretability. In response to these challenges, this paper introduces the Three Conditions for Feature Aggregation (3ConFA) framework, a feature selection approach based on ensembles that seeks to reduce dimensionality without reducing predictive performance. The 3ConFA framework integrates three key techniques; Chi-square (χ²) test, Information Gain (IG), and Decision Tree-based Recursive Feature Elimination (DT-RFE), and applies stringent conditions to select only the most relevant features. A feature is retained if and only if it satisfies all three conditions: (1) IG score ≥ mean IG threshold, (2) χ² score ≥ mean χ² threshold, and (3) DT-RFE importance score = 1. Experimental evaluation on ten benchmark datasets demonstrates the effectiveness of the framework, achieving feature reductions of up to 98.75% (e.g., Dexter dataset) while improving classification accuracy (e.g., Madelon: 78% → 85%). Performance metrics (precision, recall, F1-score) were consistently enhanced after feature selection, confirming that 3ConFA enhances model generalization without tradeoff in critical information. The framework’s adaptability across diverse datasets highlights its potential for applications in fraud detection, healthcare, and image classification. This study contributes a structured, condition-driven feature aggregation approach that outperforms traditional filter and wrapper methods. Future work may explore adaptive thresholding and integration with deep learning models
Interaction of elasmobranchs with litter in South Brazil: ingestion and oviposition patterns
No full textInternational audienceElasmobranchs, one of the most endangered animal groups, have been affected by different anthropogenic stressors, including marine litter. To better understand the interactions of elasmobranchs with litter we analyzed the gastrointestinal tract of sharks and examined skate nest composition in southern Brazil. Among 47 sharks caught in longline fisheries, three had ingested mesoplastic items (FO = 6.4 %); a subsample of 18 of these sharks was assessed for microplastic ingestion, revealing 34 microplastics in 12 individuals (FO = 66 %). Gillnetcaptured sharks (n = 7) only ingested three microplastics (FO = 42.85 %). Sixteen skate nests examined for litter interaction presented a total of 269 egg capsules and 1676 litter items. The FO of litter in nests was 100 %, with plastic being the predominant material (96.71 %), mainly fishing lines (85.98 %). While litter ingestion by sharks was less frequent than other groups, litter prevalence in skate nests was high and primarily linked to fishing activities
Les pollutants métalliques et organiques altèrent-ils la régulation de l'état physiologique et l'histoire de vie des oiseaux marins ?
No full textMarine ecosystems face growing pressures from human activities such as overfishing, agriculture, industry, and coastal urbanisation. Pollutants from industrial and agriculture runoffs, wastewater, and discarded fishing gear introduce trace elements, persistent organic pollutants, pharmaceuticals, and plastic-related chemicals into marine environments. These contaminants integrate into food webs, bioaccumulate, and may biomagnify across trophic levels, posing risks to wildlife and human health through seafood consumption. Seabirds, as top predators, often exhibit high contaminant loads, making them valuable bioindicators. Their ability to accumulate contaminants over broad spatial and temporal scales provides critical insights into environmental contamination and ecosystem health. In this work, I assessed the drivers and effects of chemical contamination—specifically trace elements and emerging pollutants—in three seabird species breeding along the Portuguese west and south coasts: the yellow-legged gull (Larus michahellis), Audouin’s gull (Ichthyaetus audouinii), and Cory’s shearwater (Calonectris borealis). These species, with distinct foraging strategies, serve as sentinels of contamination in their habitats and food webs. First, I evaluated adult blood mercury (Hg) concentrations across five breeding colonies, investigating the influence of diet (via stable isotopes: δ13C, δ15N, δ34S), foraging behaviour (via GPS tracking), and species-, region-, and individual-specific traits. Second, I quantified 14 additional trace elements to describe spatial contamination patterns and assessed their collective effects on adult physiology using immuno-haematological markers. Third, I established a baseline of Hg contamination in gull chicks from urban and natural colonies, analysing stable isotopes as potential drivers of Hg uptake. Finally, I conducted a non-target high-resolution screening of emerging pollutants in the blood of adults and chicks, testing whether breeding colony, species, or age influenced contaminant profiles. Hg exposure was highest in adults from natural colonies, with 37% of individuals at moderate risk of Hg toxicity. In contrast, urban-dwelling gulls exhibited up to 20-fold higher Pb levels than those from natural colonies, revealing a trade-off between Pb exposure in urban areas and Hg in natural habitats. Hg concentrations varied by species and site, showing links with stable isotopes and foraging habitats. These findings underline the importance of colony-, species-, and individual-level dietary habits in explaining Hg accumulation, while also highlighting the potential role of background Hg and isotopic baselines in shaping bioaccumulation patterns. Despite elevated Hg (and Pb in urban gulls), associations with physiological parameters were limited, suggesting a need for further study. Notably, gull chicks from natural colonies had some of the highest blood Hg levels ever reported in seabird chicks, while urban chicks showed up to 2-fold lower concentrations. As in adults, Hg-isotope relationships varied by colony, with δ15N correlating positively with Hg only in urban chicks, reflecting colony-specific biomagnification pathways. More than 200 emerging pollutants were detected in the blood of adults and chicks, including pharmaceuticals, pesticides, industrial compounds, and illicit drugs. Pharmaceuticals were most frequent, but insecticides drove the strongest differences between age groups. This highlights the pervasive presence of emerging pollutants and raises concern about early-life exposure in seabirds. Overall, this doctoral research offers a framework for understanding species- and site-specific contaminant dynamics. It emphasises interactions between foraging ecology, trophic position, contaminant exposure, and potential health effects. Findings underscore the importance of continued ecotoxicological monitoring, particularly for vulnerable life stages such as chicks and at-risk seabird populations.Les écosystèmes marins subissent des pressions croissantes dues à des activités humaines telles que la surpêche, l’agriculture, l’industrie et l’urbanisation côtière. Les rejets industriels, agricoles, les eaux usées et les déchets de pêche introduisent dans l’environnement marin des éléments traces, des polluants organiques persistants, des produits pharmaceutiques et des composés plastiques. Ces contaminants s’intègrent aux réseaux trophiques, s’accumulent dans les organismes et peuvent se biomagnifier, posant des risques pour la faune et la santé humaine via la consommation de produits de la mer. Prédateurs supérieurs, les oiseaux marins présentent souvent de fortes charges contaminantes, ce qui en fait d’importants bioindicateurs. Leur capacité à intégrer les polluants à grande échelle spatio-temporelle fournit des informations clés sur la pollution marine. Ce travail explore les causes et effets de la contamination chimique chez trois espèces d’oiseaux marins nichant sur les côtes ouest et sud du Portugal : le goéland leucophée (Larus michahellis), le goéland d’Audouin (Ichthyaetus audouinii) et le puffin cendré (Calonectris borealis). Leurs stratégies alimentaires distinctes en font des sentinelles pertinentes de la contamination locale. Premièrement, j’ai mesuré les concentrations de mercure (Hg) dans le sang d’adultes issus de cinq colonies, en lien avec le régime alimentaire (isotopes stables δ¹³C, δ¹⁵N, δ³⁴S), les déplacements (GPS), et des facteurs écologiques. Deuxièmement, 14 autres éléments traces ont été quantifiés pour décrire les schémas de contamination spatiale et leurs effets physiologiques via des marqueurs immuno-hématologiques. Troisièmement, une évaluation de référence a été menée sur les poussins de colonies urbaines et naturelles, en analysant les isotopes stables comme facteurs d’exposition au Hg. Enfin, un criblage non ciblé haute résolution a permis d’identifier les polluants émergents chez adultes et poussins, et d’évaluer l’effet de l’âge, de l’espèce et de la colonie. Les niveaux de Hg étaient plus élevés chez les adultes de colonies naturelles, avec 37% des individus à risque modéré de toxicité. À l’inverse, les goélands urbains présentaient des taux de plomb (Pb) jusqu’à 20 fois plus élevés, révélant un compromis entre exposition au Pb en ville et au Hg en nature. Les concentrations de Hg variaient selon l’espèce et le site, en lien avec les isotopes et les habitats exploités. Ces résultats soulignent l’importance de l’écologie alimentaire dans la bioaccumulation. Malgré des niveaux élevés de Hg (et de Pb chez les goélands urbains), peu de liens ont été observés avec les marqueurs physiologiques, appelant à des recherches complémentaires. Fait marquant, les poussins des colonies naturelles présentaient certains des taux de Hg les plus élevés jamais observés chez cette classe d’âge, alors que ceux des colonies urbaines affichaient des concentrations deux fois moindres. Le δ¹⁵N était corrélé positivement au Hg uniquement chez les poussins urbains, traduisant des schémas de biomagnification spécifiques à chaque colonie. Plus de 200 polluants émergents ont été détectés, incluant médicaments, pesticides, composés industriels et drogues illicites. Les produits pharmaceutiques étaient fréquents, mais les insecticides expliquaient le mieux les différences entre âges, étant plus abondants chez les poussins, toutes espèces et colonies confondues. Cela révèle une exposition précoce préoccupante. Ce travail propose un cadre pour comprendre la dynamique des contaminants selon l’espèce et le site, et souligne les liens entre écologie alimentaire, exposition chimique et effets sanitaires. Il met en avant l’importance d’un suivi écotoxicologique, en particulier chez les jeunes et les espèces à risque
Beyond the median line: reassessing Kinmen's geostrategic significance, past and present
No full textTaiwan Security and Diplomacy Program, FRSKinmen holds a singular position in cross-Strait relations. Located mere kilometers from Xiamen (People’s Republic of China, PRC) yet administered by Taipei (Republic of China, ROC), the archipelago defies geographic logic through historical contingency. As tensions escalate and Crimea comparisons multiply in strategic analyses, assessing the contemporary significance of Kinmen becomes essential for understanding Beijing’s broader Taiwan strategy and evaluating invasion scenarios that dominate current policy debates. Drawing on Michel Foucher’s definition of borders as “time inscribed in space”,1 this note argues that Kinmen’s geopolitical significance cannot be grasped without historicizing it at the intersection of World War II, the Chinese Civil War, and the Cold War. Only through such analysis can we understand how the archipelago contingently emerged as one of the world’s most critical flashpoints in the 1950s before gradually fading from view and, crucially, how its function has been reconfigured rather than extinguished. The thesis is twofold. First, while Kinmen retains symbolic importance as an ‘anchor’ tying Taiwan to the mainland, its function has radically shifted: from first-order military front during the 1954-1958 crises to gray zone instrumentalized for cross-Strait rapprochement and hybrid operations testing. Second, contrary to predictions drawing parallels with Crimea, a Kinmen invasion remains fundamentally counterproductive for Beijing, which derives greater strategic benefit from maintaining the archipelago under Taipei’s control as a platform for graduated pressure than from military conquest. This reassessment challenges prevailing assumptions about proximity, vulnerability, and escalation dynamics in the Taiwan Strait
Accelerating 4K Morphological Image Operations on PYNQ-Z1 and Kria KV260 FPGA Boards Using the Vitis Vision Library
No full textInternational audienc
New Advances of the Impact of Hydrogen on the Plasticity of Nickel Alloys Based on Nano-Indentation Investigations
No full textInternational audienc
Historicity in organization studies: describing events and actuality at the borders of our present
No full textInternational audienceAs soon as we go beyond the borders of our present and begin to explore remote pasts and futures, management and organization scholars are exposed to two dangers. The first is the exaggeration of continuities and anachronism about the past. The second is the projection of present ordinariness into the future. So how can we describe long-term processes of entrepreneurship, accounting, marketing, finance, information systems or innovation? This edited volume gathers a team of leading interdisciplinary team of scholars inspired by process philosophy, phenomenologies, and critical schools. After presenting issues, debates, and perspectives likely to inspire and guide historical description, the book moves to the concrete translation of this endeavor. Several examples of historical work in entrepreneurship, accounting, and organization studies are then used to show situations in which researchers have had to tackle this resonance between ontology and methodology in their historiography. It will be of great interest to scholars and students of management and organization studies. This books follows the 13th OAP workshop hosted by ESADE on June 2023