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Seeing yew for the forest: a call to action for improving conservation and restoration of the European yew (Taxus baccata L.)
No full textInternational audienceThe European yew (Taxus baccata L.) is a long-lived conifer of ecological, cultural, and historical importance across Eurasia. Despite its remarkable resilience, wide distribution, and symbolic importance, the species has experienced a long-term decline due to a complex interplay of climatic fluctuations, megafaunal extinctions, human exploitation, and insufficient regeneration. Recent studies in palaeoecology, archaeology, dendroecology, and conservation have revealed a species with greater ecological plasticity and a broader historical distribution than previously assumed. However, many fundamental questions remain unresolved, particularly regarding its biogeographical history, population dynamics, recruitment processes, and the drivers of its decline.This review stems from prior investigations of yew in the French Pyrenees and, more broadly, across Europe. These efforts led to a transdisciplinary seminar and opened a collaboration uniting >30 researchers across Eurasia. By synthesizing a wide array of data and perspectives, the article highlights key knowledge gaps and outlines emerging research priorities. These are organized thematically—past, present, and future—and include 25 questions on the species' ecological niche, life-history strategies, human interactions, genetic resilience, and conservation under global change. The article advocates for a shift towards integrative and long-term conservation strategies that embrace the historical legacies of yew populations, the general ecology of the species along with local ecological context dependence, and the urgency of future threats. By identifying pressing research needs, this review seeks to lay the foundation for new collaborative initiatives and to support evidence-based conservation of this emblematic yet understudied species
Europe's Port Achilles' Heel
No full textInternational audienceFor several years, the growing vulnerabilities of European ports have become increasingly evident, revealing how exposed critical infrastructures are to simultaneous cyber, geopolitical, and organizational risks. The rapid digitization of port operations, coupled with the deep interconnection of global supply chains, has heightened the dependence of freight flows on complex IT systems, in which even minor failures can trigger major disruptions. As a result, ports are becoming high-value targets for actors seeking either to destabilize commercial activity or exploit structural weaknesses. This research note highlights the convergence of several issues: extreme process optimization that undermines system resilience, increasing reliance on heterogeneous technologies, and persistent difficulties in coordinating multiple public and private stakeholders. At the same time, the European Union (EU) faces strategic constraints due to the absence of a unified logistical vision and stark disparities in modernization between major gateways and secondary ports. In response, four priority areas of action emerge: integrating logistical policy into the broader EU industrial strategy, accelerating the digital transformation of port infrastructure, reinforcing cybersecurity and civil-military cooperation mechanisms, and harmonizing operational standards to enhance the overall resilience of the European port system
Le commentaire d’arrêt pour ceux qui n’aiment pas ça. Éléments de méthode
No full textLicenceCe guide propose des éléments d’une méthode du commentaire d'arrêt sous l’angle du raisonnement et de l'argumentation juridiques, à destination des étudiants de Licence et de Master. Plutôt que de simplement prescrire « comment faire », la démarche consiste à dévoiler le « pourquoi » de chaque recommandation, transmettant ainsi la logique intellectuelle qui sous-tend la méthode
Revealing the role of functional binder PEDOT:PSSTFSI in cathode-electrolyte interphase formation on LiFe<sub>0.4</sub>Mn<sub>0.6</sub>PO<sub>4</sub> electrodes of Li-ion battery
No full textInternational audienceThe stability of the cathode–electrolyte interphase (CEI) plays a critical role in determining the long-term performance of Li-ion batteries, particularly under high-voltage operation. This work investigates CEI formation and evolution in LiFe0.4Mn0.6PO4 (LFMP) composite positive electrodes using PEDOT:PSSTFSI, a conductive polymer that replaces both carbon black and polyvinylidene fluoride (PVDF) binder in the electrode formulation. Electrochemical tests, XRD, and XPS confirm PEDOT:PSSTFSI's electrochemical stability up to 4.5 V vs. Li+/Li and non-reactivity towards the active material. Reversible redox activity is observed in XPS, but it does not affect long-term structural or electrochemical stability. XPS analysis of C 1s, O 1s, P 2p, and F 1s spectra across different charge states reveals that PEDOT:PSSTFSI promotes a thinner, more stable CEI without altering its composition compared to carbon-containing references. This reduced interfacial degradation corresponds with improved performance at higher voltages during extended cycling. The results underscore PEDOT:PSSTFSI's promise as a multifunctional binder offering conductivity, stability, and interfacial control for advanced Li-ion positive electrodes.</p
The Synthetic Absorption Line Spectral Almanac (SALSA)
No full textInternational audienceWe create the first large-scale mock spectroscopic survey of gas absorption sightlines traversing the interstellar medium (ISM), circumgalactic medium (CGM), and intergalactic medium (IGM) surrounding galaxies of virtual Universes. That is, we create mock, or synthetic, absorption spectra by drawing lines-of-sight through cosmological hydrodynamical simulations, using a new mesh-free Voronoi ray-tracing algorithm. The result is the Synthetic Absorption Line Spectral Almanac (SALSA), which is publicly released on a feature-rich online science platform (www.tng-project.org/spectra). It spans a range of ions, transitions, instruments, observational characteristics, assumptions, redshifts, and simulations. These include, but are not limited to: (ions) HI, OI, CI, MgI, MgII, FeII, SiII, CaII, ZnII, SiIII, SiIV, NV, CII, CIV, OVI; (instruments) SDSS-BOSS, KECK-HIRES, UVES, COS, DESI, 4MOST, WEAVE, XSHOOTER; (model choices) with/without dust depletion, noise, quasar continua, foregrounds; (redshift) from z=0 to z~6; (ancillary data) integrated equivalent widths, column densities, distances and properties of nearby galaxies; (simulations) IllustrisTNG including TNG50, TNG-Cluster, EAGLE, and SIMBA. This scope is not fixed, and will grow and evolve with community interest and requests over time -- suggestions are welcome. The resulting dataset is generic and broadly applicable, enabling diverse science goals such as: (i) studies of the underlying physical gas structures giving rise to particular absorption signatures, (ii) galaxy-absorber and halo-absorber correlations, (iii) virtual surveys and survey strategy optimization, (iv) stacking experiments and the identification of faint absorption features, (v) assessment of data reduction methods and completeness calculations, (vi) inference of physical properties from observables, and (vii) apples-to-apples comparisons between simulations and data
Towards precision cosmology with Voids x CMB correlations (I): Roman-Agora mock catalogs and pipeline validation
No full textInternational audienceWe construct and validate a set of multi-purpose mock galaxy catalogs designed to capture, to different degrees of accuracy, the main characteristics of the Nancy Grace Roman Space Telescope survey. These catalogs provide a foundation for void statistics and various CMB cross-correlation analyses. Our approach differs from traditional halo occupation or abundance matching methods by directly translating a reference mock catalog -- containing basic properties of the host halos -- into a new simulation (in our case Agora). This technique, which we call analog matching, assigns a halo counterpart in the new simulation to each reference galaxy through a nearest-neighbor search in a multi-dimensional parameter space. This space can include halo mass, environmental measures and other galaxy-specific attributes. By varying the composition of this parameter vector, we can generate catalogs of differing complexity and conduct systematic tests to examine the influence of modelling choices on LSS statistics. We find that analog matching based on halo mass alone, or halo mass and galaxy-type indicators, successfully reproduces the expected Roman emission-line galaxy statistics. We also show that reproducing two-dimensional galaxy clustering does not guarantee consistent void properties. Our results highlight the importance of matching void statistics for improved mock accuracy, and demonstrate that measuring voids provides independent and sensitive constraints on galaxy-halo connections beyond the matter power spectrum. An important by-product of our setup is that it is fully general and can be applied to any combination of simulation and reference catalog, provided that the desired parameter space for both is specified. The resulting Roman-Agora mock catalogs offer a versatile resource for LSS x CMB studies and a benchmark for assessing the impact of mock accuracy on cosmological observables
Joint cosmological fits to DESI-DR1 full-shape clustering and weak gravitational lensing in configuration space
No full textInternational audienceWe present a joint -pt cosmological analysis of auto- and cross-correlations between the Dark Energy Spectroscopic Instrument Data Release 1 (DESI-DR1) Bright Galaxy Survey (BGS) and Luminous Red Galaxy (LRG) samples and overlapping shear measurements from the KiDS-1000, DES-Y3 and HSC-Y3 weak lensing surveys. We perform our analysis in configuration space and, in addition to the cosmic shear correlation functions for each weak lensing dataset, we fit the tangential shear of the weak lensing source galaxies around DESI lens galaxies. Finally, we make use of the anisotropic BGS and LRG clustering information by fitting the full shape of the two-point correlation function multipoles measured over the full DESI-DR1 footprint, presenting the first full-shape analysis of DESI measurements in configuration space. We find that the addition of weak lensing information serves to improve, with respect to the clustering-only case, the measurements of the power spectrum amplitude parameters and by and , respectively. It also improves measurements of the linear bias of the lens galaxies by , depending on the tracer. Our results show excellent consistency, regardless of the weak lensing survey considered, and are furthermore consistent with a companion analysis that fits -pt correlations including DESI projected clustering measurements, as well as the results published by the weak lensing collaborations themselves. Our measured values for weak lensing amplitude are , , , which are below the value preferred by Planck. Finally, our clustering-only results are in good agreement with the Fourier space full-shape analysis of all DESI tracers
High‐Throughput Fabrication of Zero‐Mode Waveguide Nanoaperture Arrays with Sol‐Gel Nanoimprint Lithography for Enhanced Single Molecule Fluorescence Detection
No full textInternational audienceZero‐mode waveguides (ZMWs) are subwavelength metallic nanoapertures enabling enhanced single‐molecule fluorescence detection at micromolar concentrations in conditions far beyond the diffraction‐limited capabilities of confocal microscopes. However, their widespread use remains limited by the complexity and cost of the nanofabrication techniques, such as focused ion beam and electron‐beam lithography. Here, a scalable, cost‐effective, and high‐throughput method for fabricating high‐performance ZMW arrays is presented, which combining sol‐gel nanoimprint lithography (NIL) with hydrofluoric acid (HF) vapor‐phase etching. This approach enables the parallel fabrication and massive replication of ZMW nanoapertures with attoliter volumes, without requiring expensive equipment. The optical performance of the resulting ZMWs is validated through a series of single‐molecule fluorescence experiments, including burst analysis, fluorescence correlation spectroscopy (FCS), and single‐molecule Förster resonance energy transfer (smFRET). The ZMW nanoapertures demonstrate up to 8× fluorescence brightness enhancement, sub‐millisecond temporal resolution, and broadband spectral operation across the visible range. This method represents a significant advance in making nanophotonic devices more accessible, paving the way for a broader adoption of ZMWs in single‐molecule biosensing and integrated nanophotonic systems
