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Ten assertions on einkorn from a participatory living-lab: right or false?
No full textInternational audienceHighlights: • French farmers grow very few varieties of einkorn, whereas there is a huge diversity in the einkorn species! • Einkorn yield is very few mentioned as a criterion farmers are interested in. • Einkorn may be adapted to a large range of environments but the current varieties are not well adapted to agroforestry. • Einkorn is not adapted to celiac patients and seems no more digestible than durum wheat with in vitro experiments. • Einkorn, considered a minor cereal, is of major economic interest.Abstract: A participatory living-lab, implemented in Occitania region (south of France), is clustering farmers, processors, chefs, researchers, teachers, students and citizens, interested by einkorn (Triticum monococcum subsp. monococcum). During meetings, field days, open laboratories days, farms or mills visits, several assertions were collected and the ten most commonly cited were selected. For each assertion, experiments were set up and the results were compared with the scientific literature in order to discuss, confirm or refute them. We concluded by right or false for each assertion: “French farmers grow very few varieties of einkorn”: right, “There is no genetic diversity in the einkorn species”: false, “Yield is the only trait farmers are interested in”: false, “The einkorn is only adapted to very specific environmental conditions”: false, ““IGP haute Provence” is the best adapted to our Living Lab cropping conditions”: false, “Einkorn is not adapted to agroforestry”: right, with the current varieties, “Einkorn is of great benefit to celiac patients”: false, “Einkorn is more digestible than durum wheat”: false, ““IGP Haute Provence” is the variety of einkorn that makes the best pasta”: false, “Einkorn is less profitable than wheat because of its low yield”: false . The participatory einkorn breeding program being implemented will allow to meet the constraints and requirements of all stakeholders
Proof of concept for manufacturing of composite tapes with household PolyEthylene Terephthalate (PET) as matrix
No full textInternational audienceNew recycling method for PET is investigated by manufacturing thermoplastic tapes using recycled PolyEthylene Terephthalate (PET) as matrix. PET, which is widely used in the packaging industry, especially for bottles, remains a challenge due to the degradation of its properties during mechanical recycling. Faced with these challenges, a new recycling method for PET is investigated by manufacturing recycled and recyclable thermoplastic tapes using recycled PET as matrix. The process is based on a dissolution-precipitation method inspired by the phase inversion membrane technique. A solubility theory have been used to identify the best solvent/non-solvent combinations.Experimental results show the efficiency of three solvents: Trifluoroacetic Acid (TFA) , Hexafluoroisopropanol (HFIP) and Gamma-Valerolacone (GVL) combined with water and ethanol as non-solvent and evaporation to dissolve and precipitate PET in the fibrous reinforcement to create the thermoplastic tape. Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) analyses show that the chemical structure of PET has been preserved. SEM images reveal the influence of the choice of solvent/non-solvent combination on porosity and pore distribution in the material.Proof-of-concept studies carried out with TFA and HFIP suggest that the HFIP/ethanol combination is the most suitable for minimizing degradation and maximizing the matrix content in the fibrous reinforcement. This work therefore lays the foundations for the development of this new recycling method as part of a move towards a circular economy and a reduction in the impact of composite materials, which are difficult to recycle
Simultaneous Rational Number Codes: Decoding Beyond Half the Minimum Distance with Multiplicities and Bad Primes
No full textInternational audienceIn this paper, we extend the work of (Abbondati et al., 2024) on decoding simultaneous rational number codes by addressing two important scenarios: multiplicities and the presence of bad primes (divisors of denominators). First, we generalize previous results to multiplicity rational codes by considering modular reductions with respect to prime power moduli. Then, using hybrid analysis techniques, we extend our approach to vectors of fractions that may present bad primes. Our contributions include: a decoding algorithm for simultaneous rational number reconstruction with multiplicities, a rigorous analysis of the algorithm’s failure probability that generalizes several previous results, an extension to a hybrid model handling situations where not all errors can be assumed random, and a unified approach to handle bad primes within multiplicities. The theoretical results provide a comprehensive probabilistic analysis of reconstruction failure in these more complex scenarios, advancing the state of the art in error correction for rational number codes
Saturation-Based Adaptive Tracking Control of Underwater Vehicles: From Theoretical Design to Real-Time Experiments
No full textInternational audienceTracking control of an autonomous tethered underwater vehicle (ATUV) for a successful marine operation is a challenging task due to the complex and nonlinear dynamics of the vehicle characterized by parametric uncertainties. Besides these issues, the vehicle mainly operates in an uncertain and unpredictable environment. To deal with the ATUV control tracking problem, this article proposes a new tracking control approach that will be named saturation-based adaptive computed torque+ (SACT+). The proposed SACT+ is designed using a variable saturation function, a computed torque structure, a saturation-based dynamic feedback, and an adaptive mechanism. Then, several arguments, based on the well-known Lyapunov techniques, are proposed to prove the stability behavior of the final closed-loop dynamics. This ensures the convergence (theoretically) of the vehicle tracking error to the origin, leading to stable and safe operations. However, this tracking error (experimentally) only stays around the origin due to many factors, such as the measurement noise from the vehicle’s sensors, the inherent uncertainties of the vehicle combined with external disturbances from the marine environment, etc. Different tests are conducted in real-time using our underwater vehicle Leonard prototype to validate the proposed SACT+. The obtained experimental results show the effectiveness and robustness of the proposed SACT+ approach in real-life cases. Finally, the performance and energy consumption indices, as well as comparative experimental studies with two well-established controllers (from the literature), confirm the relevance of the proposed approach for controlling small-sized and/or low-cost underwater vehicles
Modeling of nonlinear viscoelasticity and stress softening in soft tissues
No full textInternational audienceThis paper deals with the mechanical behavior of soft living tissues under load-unload and relaxation cyclic strains. It proposes a thermodynamic model formulated within the Generalized Standard Materials framework that incorporates both Mullins’ effect and viscoelasticity, integrating the history dependent behavior of the material under finite strain. A key innovation lies in the use of a common softening function to modulate both the hyperelastic and viscous components, capturing history-dependent behavior more accurately. Viscous parameters are adjusted based on the loading history via the maximum strain invariant. Numerical implementation is validated against uniaxial tensile tests on porcine perineal tissues and a global Sobol sensitivity analysis confirms that elastic, viscous, and Mullins-related parameters are identifiable from different phases of the loading protocol. This model provides a unified, thermodynamical consistent tool for simulating soft tissue mechanics
Éducation verte, éducation de demain
No full textInternational audienceComment mettre en place une nouvelle forme d’éducation, l’éducation verte, afin de faire face aux défis environnementaux de notre époque ? La France, l’Europe et le monde ne semblent pas encore en prendre pleinement le chemin.Pourtant, dans ce monde désordonné, des initiatives d’éducation verte émergent à l’échelle locale, nationale et internationale. Comment les rendre audibles ? Comment permettre à toutes et tous de participer à une réflexion et une action majeure pour nos sociétés ?Cet ouvrage part du constat de crise de notre école et de notre système éducatif pour examiner les perspectives possibles. À partir d’exemples concrets, l’auteur propose une réflexion synthétique et une mise en perspective qui démontre que l’éducation verte n’est pas une utopie.En définissant l’éducation verte comme l’éducation de demain, il ne s’agit pas d’une simple affirmation, mais d’une analyse globale nécessaire sur les modalités, les finalités et le rôle de l’éducation et de la pédagogie dans nos sociétés.Faire de l’éducation verte un véritable projet de société, fondé sur l’idée d’un nouveau contrat social et écologique, est bien l’affaire de toutes et tous
Intragenerational conflict undermines cooperation with the future
No full textFuture generations have no agency in today's decisions, making their well-being a defining challenge of our time. Climate change, biodiversity loss, and resource depletion all depend on trade-offs between immediate gains and long-term sustainability. These dilemmas are often attributed to shortsightedness. We show instead that the critical obstacle lies within generations themselves: coordination failures among contemporaries can undermine sustainability even when individuals care about the future. Using a lab-in-the-field intergenerational goods game with a threshold-based regeneration rule, we compare settings with a single decision maker per generation to ones with three contemporaries deciding simultaneously without communication. When individuals act alone, resources are almost always preserved; when contemporaries must coordinate, conservation collapses. Our models explain this pattern by combining intergenerational altruism with beliefs about others' restraint: pessimistic expectations erode altruistic motives, driving overextraction. These insights have direct implications for climate governance and natural resource management, where failures in coordination today can be as detrimental as lack of concern for the future
Abrodictyum polynesicum (Hymenophyllaceae, Polypodiidae), a new fern species for the French Polynesia
No full textInternational audienceThe filmy fern Abrodictyum asae-grayi (Hymenophyllaceae) is thought to be distributed from New Guinea to French Polynesia. However, specimens from the Marquesas Islands and some populations from the Society Islands show clearly erect rhizomes, while the species A. asae-grayi is described as having creeping rhizomes. In-depth examination of the herbarium specimens and phylogenetic analysis demonstrate that the specimens with creeping rhizomes and those with erect rhizomes define two distinct species. The new species, A. polynesicum, endemic to French Polynesia, is discussed and described here
Early blood-material interfacial events and capillary transport on nanoparticle-modified nanofibers
No full textInternational audienceElectrospun poly(ϵ-caprolactone) (PCL)nanobrous mats are widely considered for blood-contacting wound dressings and small-diameter vascular applications; however, their intrinsic hydrophobicity limits rapid wetting and controlled interaction with blood. In this work, we modulate the interfacial response of PCL nanobers by incorporating oxideshelled silicon nanoparticles (SiNPs) synthesized by pulsed laser ablation in liquid, a ligand-free approach that avoids organic stabilizers and preserves surface reactivity. Two composite architectures were designed: SiNPs embedded within the ber bulk (PAC-1, -4, -16) and SiNPs preferentially exposed at the ber surface (SPAC-1, -4, -16), with systematically increasing nanoparticle loadings. Structural characterization conrmed the retention of a homogeneous brous morphology and the targeted nanoparticle distribution. The dynamic interaction with whole blood was quantied using time-resolved contact-angle measurements, complemented by top-view optical microscopy and three-dimensional prolometry of dried droplets. Pristine PCL remained strongly hydrophobic, exhibiting a high apparent contact angle that decreased only marginally over time (≈110° to ≈100° over 20 min), whereas a hydrophilic PCL functionalized with APTES showed rapid spreading. Incorporation of SiNPs within the ber volume led to only a moderate enhancement of wettability (final angles ≈80-90°), and dried droplets retained compact morphologies with limited spreading. In contrast, surface-decorated mats displayed a sharp, concentration-dependent transition toward highly wettable behavior: for SPAC-16, the contact angle fell below 20°, droplet proles became markedly attened, and microscopy revealed extended plasma-rich regions surrounding a red-cell-rich core, indicative of pronounced phase separation within the nanobrous network. Consistently, gravimetric measurements showed substantial increases in both water uptake (from ≈400% for PCL to > 700% for SPAC-16) and blood uptake (up to ≈1200% for PAC-16 and ≈1050% for SPAC-16).Overall, these results establish laser-synthesized SiNPs as an effective and chemically simple strategy to control blood wetting, imbibition, and phase separation in electrospun PCL nanofibers. Importantly, nanoparticle localization - within the fiber bulk or at the fiber surface - governs distinct regimes of interfacial behavior. This work provides mechanistic insight into early blood-material interactions on nanofibrous substrates and offers clear design guidelines for tailoring fluid management and hemocompatibility in advanced wound dressing and blood-contacting biomaterials
Regulatory mechanisms of ER body formation and its function in Brassicaceae plants
No full textInternational audienceEndoplasmic reticulum (ER) bodies are unique ER subdomains with a spindle-shaped structure in Brassicaceae, Cleomaceae, and Capparaceae plants, and they accumulate high levels of β-glucosidases (BGLUs). ER body-localized BGLUs are crucial for the hydrolysis of glucosinolates that are responsible for the chemical defense. In Arabidopsis thaliana, ER body-deficient mutants are vulnerable to non-herbivorous arthropods and non-pathogenic fungi, and display altered root microbiota assembly. ER bodies are predominantly observed in seedlings and roots, as well as in the epidermal cells above leaf midveins and margins. ARABIDOPSIS THALIANA MERISTEM LAYER1 (ATML1) transcription factor controls ER body accumulation in leaves through the activation of the NAI1 transcription factor, which upregulates the expression of ER body-related genes. ER bodies are further induced by wounding, indicating that their accumulation is also controlled in response to environmental signals. Jasmonate plays a key role in regulating ER body induction through CORONATINE INSENSITIVE1 (COI1), and the transcription factors MYC2, MYC3, and MYC4, which further control the expression of MYB47 and MYB95, key regulators of ER body-related genes. The conservation of orthologous and paralogous genes among ER body-related genes is observed in Brassicaceae plant genomes, indicating the conservation of ER body accumulation mechanisms among Brassicaceae species