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New additions to the vascular flora of the Kastellorizo island group (East Aegean Islands, Greece)
No full textInternational audienceThis work is a contribution to the knowledge of the vascular flora of the archipelago (SEGreece), which is part of the South Anatolian biogeographical province. An autumn survey(October 2025) identified nine species new for the archipelago (Amaranthus viridis, Dittrichia graveolens, Eclipta prostrata, Euphorbia prostrata, Gastridium phleoides, Orobanche minor, Portulaca oleracea, Setaria adhaerens, Sorghum halepense) and clarified the distribution of several taxa of great biogeographical interest (e.g. Campanula kastellorizana, Colchicum macrophyllum, Cyclamen maritimum, Dianthus muglensis, Polygonum praelongum, Thliphthisa brevifolia). A checklist is also presented for Aghios Georgios, a small satellite islet (1 ha) with a high species richness as 149 plant taxa have been recorded in total. The Kastellorizo archipelago, rich in about twenty endemic vascular plants, is a very interesting biogeographical entity that deserves increased protection of its biodiversit
Evaluation of the impact of e-beam and X-ray irradiation conditions on radical generation in PE/EVOH/PE multilayer film
No full textInternational audienceSterilization of biopharmaceutical products has commonly employed gamma radiation from cobalt-60, a radioisotope with associated security and supply chain risks. Increased use of non-radioisotope alternative ionizing energy technologies, such as electron beam (e-beam) and X-rays, is promising but has been hindered by lack of thorough evaluation of the compatibility of these techniques with product materials. This study investigates radical generation in a polyethylene (PE)/ethylene-vinyl alcohol copolymer (EVOH)/PE multilayer film product (Sartorius Flexsafe (R) with the S80 film) under varying e-beam and X-ray irradiation conditions to address data gaps for these materials and technologies. Utilizing a full factorial design of experiments (DoE), we examined the effects of irradiation technology, dose level, dose rate, processing temperature, and ambient oxygen concentration on radical formation, as quantified by electron spin resonance (ESR). Our results indicate that the type of ionizing technology (e-beam vs. X-ray) does not significantly affect radical concentration generation in the materials. However, higher doses and lower temperatures were found to correlate with increased radical concentrations, while elevated oxygen levels effectively suppressed radicals through a presumed scavenging mechanism. For e-beam processing, a higher dose rate reduced radical accumulation, while the opposite trend was found for X-ray irradiation. Complementary Fourier-transform infrared spectroscopy (FTIR) and principal component analysis (PCA) revealed subtle oxidation differences of PE under specific irradiation condition
Conclusion. L'empreinte singulière des sports olympiques d'hiver
No full textInternational audienceCe chapitre de conclusion referme l’aventure éditoriale vouée à explorer l’histoire des sports olympiques d’hiver. L’analyse souligne la singularité de ces sports et de l’évènement international qui les porte – soit les Jeux olympiques d’hiver. Elle revient en particulier sur la sécularisation paradoxale de la manifestation, le registre d’institutionnalisation spécifique des sports d’hiver, leur universalité discutable et leur avenir incertain au regard des bouleversements écologiques du XXIe siècle
RGPD et transidentité : précisions bienvenues sur le principe d'exactitude et le droit de rectification du RGPD à l'égard des données relatives à l'identité de genre
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Biofouling in milli-labyrinth channels of drip irrigation systems using reclaimed wastewater: A review of optical methods and numerical modelling
No full textInternational audienceDrip irrigation systems are known for their high water-use efficiency due to the combination of using milli-labyrinth channels to optimise flow distribution and reusing reclaimed wastewater. However, clogging andbiofouling remain significant challenges that affect system performance and lifespan. This review provides acomprehensive overview of biofouling in drip irrigation systems, with a focus on how hydrodynamic conditionsand nutrient availability in reclaimed wastewater influence the attachment, growth, detachment, and decayof biofilm. The ability of advanced optical techniques, including particle tracking velocimetry, industrialcomputed tomography, and optical coherence tomography to visualise, measure, and analyse biofoulingprocesses in drip irrigation systems is discussed, along with their strengths and limitations. Additionally, theability of current biofilm modelling approaches, including both continuum and discrete methods, to simulatenutrient transport, microbial activity, and biofilm–fluid interactions are discussed. By combining insights fromexperimental data and computational models, this review also identifies key research gaps and presents a newframework for applying biofilm modelling to drip irrigation systems. Future research directions are suggestedto improve our understanding of drip irrigation biofouling and to predict it, to optimise emitter design, andincrease the overall reliability and sustainability of drip irrigation system
Tracing the origins of Stradivari’s resonance wood
No full textInternational audienceStradivari's violins represent the pinnacle of classical instrument making, yet the origins of the wood used to construct their soundboards have long remained unclear. By analysing 314 tree-ring series from 284 authenticated instruments, we show that the majority of soundboards were crafted from Norway spruce (Picea abies) that grew at very high elevations during the severe climatic conditions of the Maunder Minimum. Our data reveal that Stradivari frequently used wood from the same tree for multiple instruments and that its sources can be traced to the Eastern Alps. Comparison with 197 reference chronologies indicates that Stradivari's early work drew on diverse and less easily localised sources. During his "golden age" of production from the early eighteenth century onwards, he consistently selected spruce from high-altitude forests in Trentino, Italy, and most likely from the Val di Fiemme in particular. These findings provide the first large-scale dendrochronological evidence for the geographic and environmental origins of Stradivari's wood and offer new insights into both historical instrument making and the interplay between climate, materials, and musical heritage
Parameter estimation of preferential water flow in soil using particle swarm optimization inverse method: Comparison of kinematicdispersive wave (KDW) and KDW-van Genuchten (KDW-VG) models
No full textInternational audienceSwift preferential water flow through macropores can rapidly pollute groundwater, spreading agricultural and industrial contaminants and threatening water security and ecosystems. To improve the simulation of pollutant transport in soil, a software package based on the kinematic-dispersive wave van Genuchten (KDW-VG) model combined with the particle swarm optimization (PSO) method was used to simulate preferential water flow through an unsaturated soil matrix. The KDW-VG model evolved from the KDW model, replacing the KDW model's power-law function with the more physically robust Mualem-van Genuchten framework. However, existing models often require detailed measurements of water flux versus mobile water content, which limits their applicability under field conditions. In this research, observed data from four rainfall intensities from 55.58 to 160.49 (mm h -1 ), were used to calibrate both the KDW and KDW-VG models. The hydrographs from a soil column with artificial macropores were recorded to calibrate both models. Using the PSO inverse method, unknown parameters were determined by minimizing the error between observed and simulated hydrographs. The finite-difference technique was used to solve both models. The results showed that the KDW-VG model fit the observations more closely, because of the replacement of the power-law function with the Mualem-van Genuchten framework. The dispersive effect was higher at lower rainfall intensities. Overall, the KDW-VG model's parameters exhibited less sensitivity to rainfall variations, which is a key advantage. This research advances computational techniques for modelling mass transfer in environmental systems, specifically addressing preferential water flow and pollutant transport. By improving the accuracy of pollutant transport models while requiring less detailed input data, the method can be applied under field conditions to provide more reliable predictions. Future work will test the model under field conditions, extend it to varied soils, and integrate realistic macropores using advanced imaging and computation
Switching cell wall-bound polysaccharides to secreted polysaccharides in lactobacilli
No full textInternational audienceBacterial exopolysaccharides (EPS) are carbohydrate polymers secreted into the environment. EPS produced by lactic acid bacteria have many valuable properties in the food and health sectors. In this study, we isolated spontaneous mutants of lactobacilli that overproduce EPS, using a selection method based on their slow sedimentation rate in a semi-liquid medium. In the mutants selected from several strains, we detected a missense mutation in epsD, which encodes a tyrosine kinase, or an insertion in epsC, which encodes its transmembrane modulator. Both genes were located within a gene cluster involved in Wzy-dependent polysaccharide biosynthesis. We then characterized selected Lacticaseibacillus rhamnosus mutants in detail to gain insights into the mechanisms involved in EPS overproduction. We demonstrated that the single mutation D94L in the EpsD catalytic site prevents EpsD autophosphorylation. The chemical structure of the overproduced EPS was established, and consists of heptasaccharide repeating units with pyruvate substituents. In the wild-type parental strain, a polysaccharide with an identical structure was found covalently bound to the cell wall (CW) and covering the bacterial surface. In conclusion, our results indicate that the switch from CW-bound polysaccharides to EPS released into the environment is associated with a defect in autophosphorylation of the EpsD tyrosine kinase
Apport modélisation des hauteurs d’eau dans les plaines d’inondation avec les GNN
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Isolation and characterization of 16 new microsatellite loci markers for the European red squirrel (Sciurus vulgaris)
No full textInternational audienceBackground Eurasian red squirrels (Sciurus vulgaris) are common in Europe and Asia, but are declining in many regions across their range. As continental European populations are now facing current and future threats from invasive species in addition to existing anthropogenic pressures it will be important to carefully monitor these populations. Non-invasive genetic sampling methods are a useful tool in conservation assessments, but often require techniques such as microsatellite markers that can be used with lower quality DNA. It remains helpful to increase the resolution of these assessments by identifying additional genetic markers.We describe new microsatellite markers developed from European red squirrels from France and use them to assess genetic diversity in populations in southern France. Methods and ResultsWe used Illumina sequencing to characterize microsatellites from tissue samples of S. vulgaris. Using 7 tissue samples we assessed amplification and polymorphism in 48 microsatellite inserts and further evaluated 16 of these microsatellite loci in hair samples from 120 individuals from four populations. In the 104 samples for which those loci amplified, there was an average of 6.1 alleles amplified per locus, with mean observed and expected heterozygosities of 0.44 and 0.59, respectively. Only one locus showed significant deviation from HWE across all populations.The same locus exhibited a likely presence of null alleles.Conclusions We describe 16 new microsatellite loci, with caution required for one locus in analyses sensitive to null alleles. These new loci can help provide increased resolution in population genetic assessments of red squirrels in continental Europe.</div