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An annotated reference library for supporting DNA metabarcoding analysis of aquatic macroinvertebrates in French freshwater environments
No full textInternational audienceFreshwater ecosystems are increasingly threatened by human activities, leading to biodiversity loss and ecosystem degradation. Effective biodiversity monitoring, particularly through the use of aquatic macroinvertebrates as bioindicators, is crucial for assessing ecological health. While traditional morphological methods face limitations, DNA metabarcoding offers higher accuracy and efficiency in species identification using environmental DNA. However, the success of metabarcoding is contingent on the quality of reference libraries, which are often incomplete or biased. This study aimed to construct and share a comprehensive COI-based DNA barcode library for freshwater macroinvertebrates in France, specifically targeting short gene regions amplified with fwhF2/fwhR2N primers, suitable for degraded DNA. A list of species occurring in French freshwater ecosystems was established from official national checklists and Alpine lake surveys. The resulting library was analysed for taxonomic completeness, barcode coverage and cryptic diversity. The checklist consisted of 2,841 species across 10 phyla, for which 56% had at least one COI-5P sequence available in the Barcode of Life Data System (BOLD). The analysis of cryptic diversity, based on Barcode Index Numbers (BINs) highlighted a potential high rate of cryptic diversity, although it might have been overestimated due to the wide geographic origin of the sequences. Alignment challenges with the primers were identified for certain taxa, particularly amongst Coleoptera, Diptera and Malacostraca. The genetic diversity approached by the number of haplotypes per species highlighted that most of the species have limited diversity, with only three species having more than 100 haplotypes. Finally, this study showed that a total of 57 haplotypes were shared amongst 116 distinct species. This work emphasises the need for expanded sequencing efforts to improve barcode coverage and highlighted the pitfalls associated with the use of these primers for further biodiversity assessment of macroinvertebrates with DNA
Observation of nuclear modification of energy-energy correlators inside jets in heavy ion collisions
No full textInternational audienceEnergy-energy correlators are constructed by averaging the number of charged particle pairs within jets, weighted by the product of their transverse momenta, as a function of the angular separation of the particles within a pair. They are sensitive to a multitude of perturbative and nonperturbative quantum chromodynamics phenomena in high-energy particle collisions. Using lead-lead data recorded with the CMS detector, energy-energy correlators inside high transverse momentum jets are measured in heavy ion collisions for the first time. The data are obtained at a nucleon-nucleon center-of-mass energy of 5.02 TeV and correspond to an integrated luminosity of 1.70 nb. A similar analysis is done for proton-proton collisions at the same center-of-mass energy to establish a reference. The ratio of lead-lead to proton-proton energy-energy correlators reveals significant jet substructure modifications in the quark-gluon plasma. The results are compared to different models that incorporate either color coherence or medium response effects, where the two effects predict similar substructure modifications
Modèles 3D multi-scalaires, lasergrammétriques et photogrammétriques, de sites ornés du massif de l’Erongo (Namibie, Afrique australe)
No full textInternational audienceLe nord du massif de l’Erongo (Namibie, Afrique australe) présente plusieurs sites ornés de premier ordre, dont l’étude nécessite une mise en contexte géomorphologique. Les granites et granodiorites du Crétacé affleurent sous forme de longues croupes et de chaos de blocs formant des abris dans lesquels se trouve l’art pariétal, ainsi que des séquences d’occupations humaines datant au moins de la fin du Pléistocène. Dans le cadre du projet ANR Cosmo-Art (ANR-21-CE27-0011 ; https://cosmo-art.org/), l’analyse des parois ornées et du contexte des chaos de blocs a motivé le déploiement d’une méthode de relevés 3D rapide et adaptée à ces environnements singuliers. A l’échelle du site (pluri-hectométrique), les relevés sont conduits par photogrammétrie avec un drone Mavic 2 pro. A l’échelle du chaos (pluri-décamétrique), les relevés sont réalisés avec un lidar terrestre Faro Focus 3D. Enfin, à l’échelle de la paroi (pluri-métrique), les relevés sont conduits par photogrammétrie avec un APN plein format. En combinant ces méthodes de numérisation, nous abordons les sites de façon multiscalaire tout en profitant de l’intérêt particulier que chacune apporte : couverture large et référencement simplifié avec le drone, justesse géométrique avec le lidar terrestre, haute résolution avec la photogrammétrie sur paroi. Avec cette approche, un site peut être relevé en une ou deux journées avec deux opérateurs. Plusieurs procédés et plusieurs logiciels d’assemblage et de consolidation sont ensuite testés (Register, Cyclone 3DR, Metashape, Cloud-Compare, Reality Capture…). Quatre sites ont déjà été traités, livrant une documentation homogène pour les analyses archéologiques et les études géomorphologiques : Ekuta, Leopard Cave, Fäckelträger et Seal Rock Shelter
Isokinetic Testing After Anterior Cruciate Ligament Injury Showed a Greater Hamstrings/Quadriceps Ratio at 240°/S Over 6 Months From Injury but No Difference of Limb Symmetry Index
No full textInternational audiencePurpose: To assess preoperative quadriceps and hamstring strength at various time points after anterior cruciate ligament (ACL) injury but before ACL reconstruction.Methods: Patients who underwent isokinetic muscle strength testing before planned ACL reconstruction were included. Patients were placed in 1 of the following 3 groups on the basis of time from injury to testing: <3 months, 3 to 6 months, and 6 to 12 months. Among these 3 groups, hamstring and quadriceps limb symmetry index (LSI) and hamstring/quadriceps (H/Q) ratios were compared. A total of 100 patients were included (<3 months [n = 55]; 3-6 months [n = 31]; and 6-12 months [n = 14]).Results: There were no significant differences between patients in the 3 groups in regards to age, body mass index, or flexion range of motion, but there was a greater proportion of female patients in the 6 to 12 month group than the other groups. No significant differences in quadriceps or hamstring strength were noted among the 3 groups. H/Q ratio was significantly greater in the 6 to 12 month group than the less than 3 months and 3 to 6 months groups, with concentric testing at 240°/s. No correlation was found between patient sex and LSI or H/Q ratios.Conclusions: Patients who underwent isokinetic muscle strength testing 6 to 12 months after ACL injury had a greater H/Q ratio at 240°/s than those who were testing within 6 months of injury. No differences in hamstring or quadriceps LSI were noted on the basis of time.Clinical relevance: An understanding of the factors that influence preoperative isokinetic muscle strength testing (including time from injury to surgery) is important, given associations noted between preoperative strength and postoperative strength recovery after ACL reconstruction
Mass and Momentum Transfer at fluid-porous interfaces: Jump Boundary conditions for non-parallel Flows
No full textInternational audienceWe derive boundary conditions for two-dimensional parallel and non-parallel flows at the interfaceof a homogeneous and isotropic porous medium and an overlying fluid layer by solving a macroscopicclosure problem based on the asymptotic solution to the generalized transport equations (GTE) in theinterfacial region. We obtained jump boundary conditions at the effective sharp surface dividing the ho-mogeneous fluid and porous layers for either the Darcy or the Darcy-Brinkman equations. We discussthe choice of the location of the dividing surface and propose choices which reduce the distance with theGTE solutions. We propose an ad-hoc expression of the permeability distribution within the interfacialregion which enables to preserve the invariance of the fluid-side averaged velocity profile with respectto the size r0 of the averaging volume. Solutions to the GTE, equipped with the proposed permeabilitydistribution, compare favorably to the averaged solutions to the pore-scale simulations (PSS) when theinterfacial thickness ∆ is adjusted to r0 . Numerical tests for parallel and non-parallel flows using the ob-tained jump boundary conditions or the generalized transport equations show excellent agreement withthe GTE solutions, with experiments and pore-scale simulations. The proposed model of mass and mo-mentum transport is predictive, requiring solely information on the bulk porosity and permeability andthe location of the solid matrix of the porous medium. Our results suggest that the Brinkman correctionsmay be avoided if the ratio a = ∆/δB of the thickness of the interfacial region to the Brinkman pene-tration depth δB is large enough, as the Brinkman sub-layer is entirely contained within the interfacialregion in that case. Our results can be easily extended to deal with three-dimensional configurations andanisotropic porous media
Dissociate Dimensions to Improve Sound Metaphors Guiding the Hand Towards 3D Non-visible Targets
No full textVersion préprint.International audienceThis paper examines the improvement of sound metaphors guiding the hand of people deprived of sight towards virtual 3D targets. The quality of the metaphors is compared by target-reaching time and qualitative measures, but also by Fitts' law's throughput, a metric that can be generalized to other experimental parameters, improving the possibilities of comparison between studies. First, a unified metaphor that indicates deviation to the target with a single 3-D angle was compared with a metaphor that separates the horizontal angle (azimuth) and the vertical distance. This spatial dissociation of vertical and horizontal dimensions (DVH) enabled faster target acquisition. Based on these results, we hypothesized that providing one dimension deviation at a time (DVH seq , for sequentially) would show a similar advantage (both spatial and temporal dissociation) compared to providing them in parallel (DVH par ). Beforehand, we compared the most efficient sounds to express each dimension. The results showed better performance for a metaphor using binary vowels to indicate height and for a metaphor combining continuous coding of direction in pitch and binary stereo to indicate horizontal direction. Although DVH seq did not significantly reduce the target reach time compared to DVH par , the majority of participants preferred the simplicity of the metaphor DV H seq , which guides one dimension at a time, a strategy largely adopted by participants. However, a minority managed to take advantage of the benefit of having all the information at the same time (DV H par ) to move directly to the target
Mapping reaction mechanism during overcharge of a LiNiO2/graphite–silicon lithium-ion battery: a correlative approach by simultaneous gas analysis and synchrotron scattering techniques
No full textInternational audienceLi-ion battery degradation processes are multi-scale, heterogeneous, dynamic, and depend on the battery usage. Degradation mechanisms during overcharge of LiNiO 2 are well known at the material level featuring O 2 gas release and concomitant surface reconstruction of LiNiO 2 . However, there are still debates regarding the role of the high voltage phase formation, so called O1, on gas production. Moreover, little information is available on the effect of produced gases on the cell components (anode or sensors), or the effect of overcharge on electrode level behavior. In this work, we simultaneously measure the gas evolution using operando mass spectrometry while spatially resolving nanostructure and crystallographic lattice parameter changes using operando micro small/wide angle X-ray scattering (SAXS/WAXS) mapping during the formation and overcharge of a LiNiO 2 /Graphite─Silicon pouch cell. This new correlated operando characterization experiment allowed to (1) confirm the absence of O1 phase even with substantial gas produced at end of charge, (2) unveil the effect of gases on reference electrode and (3) show that overcharge increases in-plane reaction heterogeneities by creating local degraded regions lagging behind the ensemble electrochemistry. These findings will be important to optimize ageing of devices based on similar chemistries, in particular Ni-rich cathodes, while showing the strength of correlated characterization leading to more efficient and robust information on complex mechanism
KarstConduitCatalogue: a dataset of LiDAR derived point clouds for the analysis of karstic conduit geometry and morphology
No full textInternational audienceIn mature karst aquifers, networks of interconnected conduits focus and control water flow and solute transport. To improve the knowledge of the multi-scale geometry of typical conduits, we acquired a data set of point clouds and triangulated surface models of 16 different underground caves: KarstConduitCatalogue (Racine et al., 2025a, available at https://doi.org/10.60544/sbjr-z851). We employed terrestrial and mobile laser scanning workflows as fast and reliable methods for acquiring a dense point cloud of wall surfaces in enclosed spaces. These collected data can be used for many different purposes: evaluation of geometrical descriptors, direct numerical simulations of flow and transport, geomorphological mapping, structure and fracture mapping, etc. In this paper, we present the various assets derived from the acquisition. The conduits presented herein span a variety of karst massifs of Western and Central Europe, from low-elevation karst plateaus to higher-elevation Alpine aquifers
Enjeux éthiques et épistémiques de la création sonore collaborative : pourquoi et comment l'artiste sonore intervient-il en classe de langue?
No full textInternational audienceThis research explores the ethical and epistemic dimensions of collaborative sound creation projects within the French as a Foreign Language classroom. Questioning arising from two projects conducted in collaboration with sound artists led the researchers to examine five works resulting from artistic interventions in formative contexts, thereby establishing a corpus of interviews with the artists involved. The collected discourses highlight issues related to listening norms, the development of orality through the artists' perspective, power dynamics, roles and stances, and the potentially divergent temporalities of pedagogy and art. Finally, the study addresses the relationships of servitude maintained by these projects. This approach contributes to rethinking the links between artistic practices and language teaching and learning; it draws inspiration from artistic practices not necessarily to produce a final work, but to enrich language didactics through a critical approach to sound and listening.Esta investigación explora las dimensiones éticas y epistémicas de los proyectos de creación sonora colaborativa en el aula de francés como lengua extranjera. Los interrogantes surgidos de dos proyectos realizados en colaboración con artistas sonoros llevaron a las investigadoras a interesarse por cinco obras resultantes de la intervención artística en contextos formativos. A partir de ello, se constituyó un corpus de entrevistas realizadas a los artistas implicados. Los discursos recopilados señalandesafíos vinculados a las normas de escucha, al trabajo de la oralidad desde la percepción de los artistas, a las relaciones de poder, posiciones y posturas, así como alas temporalidades pedagógica y artística, potencialmente divergentes. Por último, se examinan las relaciones de servidumbre que pueden subyacer en estos proyectos.Este enfoque contribuye a reflexionar sobre los vínculos entre las prácticas artísticas y la enseñanza-aprendizaje de lenguas, inspirándose en la labor artística no necesariamente para la producción de una obra, sino para enriquecer la didáctica de lenguas mediante una aproximación crítica de lo sonoro y de la escucha.La recherche explore les dimensions éthiques et épistémiques de projets de création sonore collaborative en classe de français langue étrangère (FLE). Les questionnements issus de deux projets menés en collaboration avec des artistes sonores, ont conduit les chercheuses à s’intéresser à cinq œuvres issues de l’intervention d’artistes en contexte formatif, et à constituer ainsi un corpus d’entretiens menés auprès des artistes impliqués. Les discours recueillis pointent des enjeux liés aux normes d’écoute, au travail de l’oralité depuis l’écoute des artistes, aux rapports de pouvoir, de places et de postures, aux temporalités pédagogique et artistique potentiellement divergentes, et enfin aux rapports de servitude entretenus par les projets. La démarche contribue à penser les liens entre pratiques artistiques et enseignement-apprentissage des langues, et à s’inspirer des pratiques artistiques non pour produire nécessairement une œuvre, mais pour enrichir la didactique des langues par une approche critique du sonore et de l’écoute
Effect of Habitual Physical Activity on Strength Loss and Fatigability in Old and Very Old Men
No full textInternational audienceABSTRACT Age‐related neuromuscular and cardiovascular declines may increase relative effort and thus fatigability during daily activities. Habitual physical activity (PA) may mitigate these alterations. This study examined the effects of age and PA on fatiguability in ecological conditions. Thirty‐nine young men (YM, 22.1 ± 3.4 years), 34 old men (OM, 71.7 ± 4.1 years), and 23 very old men (VOM, 85.8 ± 2.7 years) performed a fatigue task. Increments were scaled in percentage body mass. Maximal knee extensor force (MVC), voluntary activation (VA), and twitch amplitude (Tw) were measured at baseline, after each stage and at task failure (TF). On a separate day, maximum oxygen consumption (V̇O 2 max) was quantified during a maximal ramp test. Results For a given workload (i.e., last common stage, LCS), MVC in percentage of baseline was lower in VOM (84.6% ± 9.2%) compared to YM (94.0% ± 7.0%; p < 0.001) and OM (91.7% ± 6.3%; p < 0.01). At LCS, Tw was lower in VOM (89.3% ± 12.7%) compared to OM (99.7% ± 10.5%; p < 0.05). MVC loss was greater in YM (−35.6% ± 14.5% of baseline) compared to VOM (−23.4% ± 11.3%; p < 0.01) at TF. No difference was found between YM and OM for loss in MVC and Tw. PA level was correlated with V̇O 2 max but did not affect fatigability. Tw loss at LCS was correlated with V̇O 2 max in VOM ( r = 0.69; p < 0.05). VOM, but not OM, was more fatigued than YM for a given submaximal workload but the opposite was true at exhaustion. Fatigability in VOM was due to peripheral factors and was correlated with aerobic capacity. In VOM, unlike YM and OM, higher PA levels may be sufficient to improve aerobic capacity and reduce fatigability. Trial Registration: ClinicalTrials.gov identifier: NCT0541359