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The use of eponyms can also promote gender equity in modern taxonomy
No full textInternational audienceThere is an ongoing debate about how species are named, with several calls to revise naming conventions (e.g., Guedes et al. 2023, Harris and Xavier 2023). The science of describing species, taxonomy, has remained largely unchanged since Linnaeus introduced the binomial system centuries ago. However, naming species is largely influenced by the societal context in which scientists operate (Ceríaco et al. 2016, Mammola et al. 2023, Toussaint et al. 2024). In a hotly debated recent paper, Guedes and colleagues (2023) specifically argued that eponyms (that is, dedications to people) are predominantly assigned to “almost universally White, male upper-class Europeans” and advocated for discontinuing their use
Next-Gen AI Orchestration Platform
No full textInternational audienceNetwork Intelligence (NI) is expected to be realized in 6G by integrating AI into cross domain resource management. This demonstration showcases variety of orchestration frameworks where RL-based decision-making methods have been implemented in our testbed and examined either in combination with predictive elements or separately across various scenarios. These scenarios optionally incorporate Federated Training and involve different domain settings and resource scales to evaluate performance and robustness in diverse contexts
Experimental End-to-End Optimization of Directly Modulated Laser-based IM/DD Transmission
No full textNational audienceDirectly modulated lasers (DMLs) are an attractive technology for short-reach intensity modulation and direct detection communication systems. However, their complex nonlinear dynamics make the modeling and optimization of DML-based systems challenging. In this paper, we study the end-to-end optimization of DML-based systems based on a data-driven surrogate model trained on experimental data. The end-to-end optimization includes the pulse shaping and equalizer filters, the bias current and the modulation radio-frequency (RF) power applied to the laser. The performance of the end-to-end optimization scheme is tested on the experimental setup and compared to 4 different benchmark schemes based on linear and nonlinear receiver-side equalization. The results show that the proposed end-to-end scheme is able to deliver better performance throughout the studied symbol rates and transmission distances while employing lower modulation RF power, fewer filter taps and utilizing a smaller signal bandwidth
Assessing the Ecotoxicological Effects of Emerging Drug and Dye Pollutants on Plant–Soil Systems Pre- and Post-Photocatalytic Wastewater Treatment
No full textInternational audienceEmerging pollutants such as pharmaceuticals and synthetic dyes increasingly enter agricultural soils through irrigation with treated or untreated wastewater and via biosolid amendments, raising concerns for plant health, soil functionality, and food chain safety. Their environmental behavior is governed by complex interactions between compound physicochemistry, soil properties, and plant physiology, leading to variable persistence, mobility, and ecotoxicological outcomes. This review synthesizes current evidence on the fate, uptake, and phytotoxic effects of drug and dye contaminants in plant–soil systems, and provides a comparative assessment of ecological risks before and after photocatalytic wastewater treatment. The analysis integrates findings from soil- and hydroponic-based studies addressing pollutant sorption–desorption dynamics, leaching, microbial transformations, and plant responses ranging from germination impairment and biomass reduction to oxidative stress and genotoxicity. Special emphasis is given to the formation and behavior of transformation products generated during photocatalytic degradation, which may display altered mobility or toxicity relative to parent compounds. Comparative evaluation reveals that photocatalysis substantially reduces contaminant loads and toxicity in many cases, although incomplete mineralization or the formation of reactive intermediates can sustain or enhance adverse effects under certain conditions. By linking pollutant fate mechanisms with plant and soil responses, this review highlights both the potential and the limitations of photocatalysis as a sustainable strategy for safeguarding agroecosystems in the context of expanding wastewater reuse
Partial coupling of the proliferation and differentiation programs during C. elegans intestine development
No full textInternational audienceCell proliferation and differentiation are essential processes underlying multicellular organism development. Cell proliferation arrest usually precedes terminal differentiation, suggesting that these two processes may be coordinated. Here we took advantage of the very stereotyped development of the C. elegans intestine to address whether the control of the proliferation and differentiation programs are systematically coupled. We show that delaying cell cycle arrest does not affect most aspects of intestinal differentiation but leads to a specific delay in the accumulation of late microvilli components. Reciprocally, we find that the differentiation factors ELT-2 and ELT-7 control cell cycle arrest specifically in posterior enterocytes. The occurrence of supernumerary divisions in the absence of ELT-2 and ELT-7 is associated with changes in the expression pattern of the cell cycle regulators cyclin B1 and CKI-1 and depends on the presence of the posterior Hox protein PHP-3. Our work thus demonstrates the existence of reciprocal interactions between cell proliferation and cell differentiation. It nevertheless also shows that these two processes are only partially coupled, suggesting the existence of additional mechanisms ensuring their temporal control
3D-Printed Dual-Band and Broadband Linear to Circular Polarizing Screen for K/Ka-Band Satellite Antennas With Feed-Aperture Integration
No full textInternational audienc
Saé en salle blanche pour les étudiants de BUT3 GEII : fabrication et caractérisation d’un capteur de luminosité
No full textInternational audienceDans le cadre de la réforme du BUT, une SAÉ (Situationd’Apprentissage et d’Évaluation) est proposée aux étudiants detroisième année du parcours Électronique et Systèmes Embarqués(ESE) du BUT3 GEII. En complément du cours de Physique duComposant, ce projet consiste à réaliser, dans la salle blanche duCCMO, une photodiode utilisée comme capteur de luminosité. Lesétudiants explorent ainsi l’ensemble du procédé de fabrication, afinde mettre en oeuvre une jonction PN sensible à la lumière. Lescaractérisations électriques ont confirmé le comportement attendu,avec un photocourant proportionnel à l’intensité lumineuse incidente.Ces résultats valident à la fois les acquis théoriques relatifs aufonctionnement des photodiodes et la maîtrise des procédésexpérimentaux nécessaires à leur réalisation
Time Series Models on Compact Spaces, With an Application to Dynamic Modeling of Relative Abundance Data in Ecology
No full textInternational audienceABSTRACT Motivated by the dynamic modeling of relative abundance data in ecology, we introduce a general approach for modeling stationary Markovian or non‐Markovian time series on (relatively) compact spaces, such as a hypercube, the simplex, or a sphere in a Euclidean space. Our approach is based on a general construction of infinite memory models, called chains with complete connections. The two main ingredients involved in our generic construction are a parametric family of probability distributions on the state space and a map from the state space to the parameter space. Our framework encompasses Markovian models, observation‐driven models, and more general infinite memory models. Simple conditions ensuring the existence and uniqueness of a stationary and ergodic path are given. We then study in more detail statistical inference in two time series models on the simplex, based on either a Dirichlet or a multivariate logistic‐normal conditional distribution. The usefulness of our models to analyze abundance data in ecosystems is also discussed
Experimental Demonstration of End-to-End Optimization for Directly Modulated Laser-based IM/DD Systems
No full textInternational audienceWe experimentally demonstrate the joint optimization of transmitter and receiver parameters in directly modulated laser systems, showing superior performance compared to nonlinear receiver-only equalization while using fewer memory taps, less band-width, and lower radiofrequency power
On the ground state of the nonlinear Schrödinger equation: asymptotic behavior at the endpoint powers
No full text43 pages, 6 figuresWe consider the ground states of the nonlinear Schrödinger equation, which stand for radially symmetric and exponentially decaying solutions on the full space. We investigate their behaviors at both endpoint powers of the nonlinearity, up to some rescaling to infer non-trivial limits. One case corresponds to the limit towards a Gaussian function called Gausson, which is the ground state of the stationary logarithmic Schrödinger equation. The other case, for dimension at least three, corresponds to the limit towards the Aubin-Talenti algebraic soliton. We prove strong convergence with explicit bounds for both cases, and provide detailed asymptotics. These theoretical results are illustrated with numerical approximations