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Development and validation of an interface for automated image acquisition during high-temperature environmental scanning electron microscopy experiments
No full textInternational audienceAn interface that enables automatic image acquisition during high-temperature experiments in an environmental SEM is developed. It is optimized to work on multiple regions of interest at multiple magnifications, performing image focusing (focus and astigmatism) and automatic recentering of regions of interest. Its operation has been validated by monitoring two regions of interest of a nickel-based superalloy undergoing oxidation at 950°C at different magnifications. Recording series of images at different magnifications on different regions of interest makes it possible to qualify the behavior of different areas of the sample in a single operation and/or to validate the reproducibility of the observations
Molecular phylogeny of the Acer-feeding aphid subfamily Drepanosiphinae (Insecta: Hemiptera: Aphididae) and the evolution of its endosymbiotic consortia
No full textInternational audienceThe Drepanosiphinae is a Holarctic subfamily of Aphididae comprising six genera: Drepanaphis, Drepanosiphoniella, Drepanosiphum, Megalosiphonaphis, Shenahweum, and Yamatocallis, all of which exhibit strict host plant associations, primarily with Acer species. Despite long-standing taxonomic attention, evolutionary relationships within the group remain poorly resolved, and some important aspects of their biology, such as their patterns of association with symbionts, have been unexplored despite evidence that species in the subfamily might be involved in atypical nutritional symbioses. Here, we present a molecular phylogenetic reconstruction of this subfamily and investigate the evolution of its endosymbiotic consortia. Phylogenetic analyses were conducted using multiple DNA markers, employing both Bayesian inference (BI) and maximum likelihood (ML) approaches. Endosymbionts were characterized using high-throughput sequencing of a fragment of the bacterial 16S rRNA gene. The resulting phylogenies are largely congruent across markers and methods and consistently support the monophyly of Drepanosiphinae. Drepanaphis and Drepanosiphum form a well-supported clade as sister to Drepanosiphoniella, while Yamatocallis and Megalosiphonaphis form a distinct, more distantly related clade. Within Drepanaphis, species group according to host plant use rather than traditional morphological groupings, revealing three host-associated clades: rubrum, saccharum, and grandidentatum. Endosymbiont characterization revealed that, in addition to the obligate symbiont Buchnera aphidicola, most Drepanosiphinae species also host a Sodalis-like bacterium, consistent with previous genomic evidence for a dual nutritional symbiosis with this bacterium. However, Sodalis was absent in most Yamatocallis species, indicating a complex and potentially dynamic evolutionary history of symbiotic relationships within the subfamily. Patterns of association with Wolbachia, Rickettsia, Fukatsuia, Serratia and Arsenophonus suggest a limited role in nutrition. By integrating phylogenetic reconstruction with symbiont profiling, this study provides the most comprehensive evolutionary framework to date for Drepanosiphinae and reinforces the view that nutritional symbioses in aphids are evolutionarily dynamics
Severity of complications is associated with impaired health‐related quality of life in people with type 1 diabetes
No full textInternational audienceAims Health‐related quality of life (HRQoL) assessment is increasingly integrated into type 1 diabetes (T1D) monitoring to promote a holistic approach. To investigate HRQoL in adults with T1D and to assess the impact of the severity of complications on HRQoL. Materials and Methods This is a cross‐sectional analysis of baseline characteristics of adults living with T1D included in Société Francophone du Diabète – Cohorte Diabète de Type 1 (SFDT1), a French longitudinal cohort study. HRQoL was assessed using generic (EuroQol 5‐Dimensions 5‐Level questionnaire [EQ‐5D‐5L]) and diabetes‐specific (Audit of Diabetes‐Dependent Quality of Life) instruments. The severity of diabetes complications was measured using an adapted Diabetes Complication Score Index (DCSI) ranging from 0 to 14. We used multiple imputations to deal with missing data. Results We included 1892 adults, 48% women, with a median (interquartile range [IQR]) age of 38 (28; 51) years. The mean overall EQ‐5D‐5L HRQoL score was 71.1 ± 17.7 (maximum 100), with the following number of participants negatively impacted for each domain: 271 (14%) for mobility, 94 (5%) for self‐care, 378 (19%) for usual activities, 853 (45%) for pain/discomfort and 983 (52%) for anxiety/depression. The median (IQR) DCSI was 1 (0; 2). In multivariable models, a one‐step increase in DCSI was associated with a 1.5% decrease in overall EQ‐5D‐5L HRQoL. DCSI was also inversely associated with all domains of the generic scale except anxiety/depression and 17 domains of the diabetes‐specific scale. Conclusions We observed an inverse association between the severity of complications and overall HRQoL and most of its dimensions. Our results highlight the need to reinforce the prevention of complications to improve the overall well‐being of people with T1D
Overview of LifeCLEF 2025: Challenges on Species Presence Prediction and Identification, and Individual Animal Identification
No full textInternational audienceBiodiversity monitoring using AI-powered tools has become vital for tracking species distributions and assessing ecosystem health on a large scale. Automated image- and sound-based species recognition, in particular, continues to accelerate conservation efforts by enabling rapid, low-cost surveys of vulnerable populations. However, the ever-growing variety of algorithms and data sources underscores the need for standardized benchmarks to assess real-world performance. Since 2011, the LifeCLEF lab has filled this role by organizing annual evaluations that promote collaboration among AI experts, citizen science, and ecologists. In this overview, we report on the LifeCLEF 2025 edition, which featured five distinct, data-driven tasks: (i) AnimalCLEF, focusing on open-set individual animal re-identification; (ii) BirdCLEF+, about species recognition in complex acoustic soundscape recordings; (iii) FungiCLEF, addressing few-shot classification of rare fungi species; (iv) GeoLifeCLEF, combining environmental and high-resolution remote sensing with occurrence records to predict plant species presence; and (v) PlantCLEF, aiming to identify multiple co-occurring plant species in vegetation-plot imagery. This paper provides an overview of the motivation, methodology, and main outcomes of the five challenges
No impact of black-eye symptom on foraging behaviour and reproductive success of Northern gannets following highly pathogenic avian influenza
No full textInternational audienceHighly Pathogenic Avian Influenza Virus (HPAIV) is currently causing major wild animal population crashes all over the world including Antarctica. Yet, there are important knowledge gaps on the implications of long-lasting symptoms for the ecology of surviving individuals and the conservation of their populations. Using GPS tracking devices and long-term demographic data, we examined the effects of HPAIV on a seabird population of Northern gannets (Morus bassanus) in the colony of Rouzic, France. One year after the HPAIV outbreak of 2022, the breeding gannet population declined by 38 % and 22.3 % of surviving breeders were zombie birds: they had darkened irises, a black-eye symptom indicative of past infection to HPAIV. Importantly, we demonstrate that black eyes were not associated with detectable differences in the foraging behaviour and habitat use of surviving breeding gannets. Compared to years prior to the outbreak, the foraging effort of breeding individuals was lower and breeding success was higher, aligning with Ashmole's halo hypothesis, which posits that smaller seabird populations face lower intra-specific competition for food in the vicinity of their breeding colony and thereby, have a reduced foraging range. Our results highlight the importance of density-dependant mechanisms in population responses to sudden mass-mortalities, but raise conservation concerns, especially for species facing cumulative threats. In the long-term, locally depleted populations may reach critical thresholds where individual abundance and productivity may not be sufficient to maintain a positive demographic growth rate, ultimately leading to local population extinctions
Dynamic programming on bipartite tree decompositions
No full textInternational audienceWe revisit a graph width parameter that we dub bipartite treewidth (btw). Bipartite treewidth can be seen as a common generalization of treewidth and the odd cycle transversal number, and is closely related to odd-minors. Intuitively, a bipartite tree decomposition is a tree decomposition whose bags induce almost bipartite graphs and whose adhesions contain at most one “bipartite” vertex, while the width of such decomposition measures the number of “non-bipartite” vertices in a bag. We provide para-NP-completeness results and develop dynamic programming techniques to solve problems on graphs of small btw. In particular, we show that -Subgraph-Cover, Weighted Independent Set, Odd Cycle Transversal, and Maximum Weighted Cut are parameterized by btw. We also provide the following dichotomy when H is a 2-connected graph: if H is bipartite, then H-{Subgraph/Induced-Subgraph/Odd-Minor/Scattered}-Packing is para-NP-complete parameterized by btw while, if H is non-bipartite, then the problem is solvable in XP-time
Hydrophobization of carboxymethyl cellulose by Passerini reaction: towards films with improved water vapor barrier properties
No full textInternational audienceTo address the need for developing sustainable materials with effective barriers to water vapor, this work explores the potential of self-supported films made of carboxymethyl cellulose (CMC) functionalized by the Passerini three-component reaction. Aliphatic aldehydes and tert-butyl isocyanide were grafted onto CMC backbone to yield dually hydrophobized derivatives. These modified polysaccharides were processed into films by solvent casting and their water vapor transfer properties were examined. Small-angle X-ray scattering (SAXS) experiments revealed a nanoscale organization for Passerini-modified films, attributed to the formation of hydrophobic domains characterized by a nanometric interdomain spacing. Dynamic vapor sorption (DVS) analysis demonstrated a significant reduction in moisture content water for modified films, from ≃ 1.1 g g -1 for unmodified CMC to below 0.5 g g -1 for hydrophobized derivatives at a w = 0.95. Guggenheim-Anderson-deBoer (GAB) and Zimm-Lundberg modeling showed a decrease in sorption site availability from 3 to ≃ 1.5 per glucose unit, while the size of water clusters was significantly increased. The Passerini modification also resulted in a substantial decrease of water vapor permeability (WVP) from 44 000 barrer to 2500 barrer at a w = 0.5. These results unequivocally underpin the benefits of the Passerini functionalization which allows to enhance the water vapor barrier performance. The findings highlight the potential of such a reaction for developing next-generation and bio-based packaging materials with tailored water vapor barrier properties.</div
Recent improvements in the analysis and characterization of fiber/matrix interfaces in biocomposites (Chap. 8)
No full textInternational audienceThis chapter aims to illustrate the correlation in the effect of free surface energy modification of natural fibers on the mechanical behavior of bio-based composites. It has been proved that enhancing the wettability of flax fibers by liquid epoxy resin implies a lower porosity amount in composites. The main outcome of multiscale consideration is that even if elementary fibers and yarns are embrittled and interface properties at the microscale are lowered by a thermal or chemical surface energy modification, the mechanical behavior of composites manufactured by liquid composite molding can be improved. Some questions are still open on the methodology to optimize treatments, especially on the scale at which the treatment is applied (yarn or fabric). The extension of those considerations to biocomposites with thermoplastic matrices should be done in the upcoming years to manufacture sustainable and circular composites
Recent advances in patented inhibitors targeting serine proteases in inflammatory diseases
No full textInternational audienceSerine proteases are critical enzymes involved in various physiological and pathological processes, particularly inflammation. Recent years have seen a great increase in the patenting of serine protease’s inhibitors as therapeutic strategies for inflammatory disorders with highly significant clinical translation. Serine protease inhibitors represent indeed a very active therapeutical area in many leading pathologies with inflammatory components such as vascular diseases, skin inflammation, respiratory or neurodegenerative diseases. In this review, we give an overview on targeted strategies, diversity of the chemical structures of inhibitors, significant disease applications e.g. most significant examples in the period (2017-early 2025) which includes inhibitors of plasma kallikrein, kallikrein-related peptidases, plasmin, factors XI and XII, and HtrA serine proteases. Over 60 patents have been filled during the investigated period covering nanomolar small-molecule inhibitors with varied heterocyclic structures or cyclic peptides either targeting active site or exosites. In addition, several therapeutical antibodies including bispecific antibodies or nanobodies have been also developed, some of them are already in advanced clinical trials