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Exploring lignin conformation in organic and deep eutectic solvents using small-angle neutron scattering
No full textInternational audienceLignin, a structurally intricate and heterogeneous phenolic biopolymer, holds considerable promise as a sustainable alternative to petrochemical-derived materials across diverse applications in the energy and materials sectors. However, precise lignin molecular weight and structure determination remains challenging due to its intrinsic tendency to aggregate in solution and the absence of chemically analogous polymer standards for chromatographic techniques. By employing small-angle neutron scattering, this study aims at precise measurement of lignin's polymeric conformation, aggregation behavior, and radius of gyration in organic gel permeation chromatography/NMR solvent, tetrahydrofuran (THF), and in an emerging class of solvent systems known as deep eutectic solvents (DES). These "designer" solvents, formed from tailored hydrogen bond donors and acceptors, are gaining importance for lignin extraction from biomass and analytical characterization. However, their influence on lignin conformation in solutions remains unexplored. Our study reveals that both organosolv and Indulin AT kraft lignin in THF exhibit loosely associated polymeric conformations. Upon D 2 O addition, Indulin AT undergoes moderate swelling, suggestive of partial dissolution, while organosolv lignin undergoes substantial elongation with directional ordering, resulting in flexible rod-like structures. Lignin oil from a reductive catalytic fractionation process (RCF), in contrast, remains well-dispersed in THF and shows minimal structural change with solvent polarity modulation via D 2 O addition. Indulin AT and organosolv lignin solvated in the choline chloride/oxalic acid/ethylene glycol DES adopt dense, cylindrical morphologies. These structures show moderate temperature sensitivity and notable resistance to D 2 O-induced structural perturbation, highlighting strong lignin-DES interactions. Additionally, lignin extracted from cocoa bean shells using a diol-based DES and subsequently dissolved in the same solvent demonstrates a fractal-like morphology, which evolves with D 2 O content and temperature, revealing a complex solvation landscape. These results offer molecular-level insight into lignin's solvent-dependent structural transitions, enabling more accurate molecular weight estimation and supporting optimization of lignin processing for high-performance biobased formulations and advanced materials
From black holes to solvable irrelevant deformations and back
No full textInternational audienceThis is a combined review on the Kerr/CFT correspondence on the one hand and solvable irrelevant deformations of two-dimensional QFTs - specifically, the and deformations - on the other. These subjects are interconnected, since the microscopic description of general black holes can be linked to very special irrelevant deformations of two-dimensional CFTs; conversely, one may draw interesting insights into black hole microscopics from the study of the exactly solvable and deformations. The Kerr/CFT part emphasizes the conceptual challenges faced by this proposed holographic description of general extremal black holes, especially in light of recent advances indicating that the classical geometry of extremal black holes is unreliable. The review of the and deformations is self-contained and presented from a purely field-theoretical perspective. It covers core topics such as the finite-size spectrum, thermodynamics, scattering, non-perturbative definition and the holographic dictionary for these deformations. Particular emphasis is placed upon the extended symmetries of and - deformed CFTs, including the perfect match between the symmetries derived via field-theoretic methods and the asymptotic symmetries of the dual spacetimes. These symmetries are also central to understanding the precise relationship between single-trace and - deformed CFTs and three-dimensional asymptotically linear dilaton and, respectively, warped AdS backgrounds
Targeted Photodynamic Therapy for Pancreatic Cancer: Recent Innovations from Fundamentals to <i>In Vivo</i> and Clinical Applications (2020-2025)
No full textInternational audiencePhotodynamic Therapy (PDT) is a clinically-approved medical modality to treat different types of localised conditions such as cancer, infections or skin conditions. Pancreatic cancer (PC) is a deadly cancer displaying a dramatic overall prognosis that has barely improved in decades as the majority of PC patients are diagnosed at a locally advanced or metastatic stage and cannot benefit of surgical resection which is the only curative treatment, the overall 5-year survival rate remains extremely low. Thus, finding new therapies for non-metastatic PC to improve local control as a bridge to surgical resection and improve survival outcomes remains a huge challenge. In this context, PDT could be an interesting option. This review will focus on the use of PDT with targeted photosensitisers or nanoparticles to treat PC in recent studies (2020-2025) from in vitro to in vivo experiments and clinical applications
The Lund -jet plane
No full textInternational audienceWe compute the primary Lund plane density for jets initiated by a massive () quark to single logarithmic accuracy in Quantum Chromodynamics (QCD). In order to capture mass effects, we consider quasi-collinear factorisation and we include contributions from the running of the QCD coupling and from collinear evolution, in a variable flavour-number scheme. Furthermore, the resummation of soft logarithms, including clustering effects, is performed numerically, keeping the full dependence on the -quark mass. While our all-order results can be applied to both hadron and lepton colliders, we present, as first phenomenological application, the resummed calculation of the Lund plane density in collisions at , matched to tree-level matrix elements
Single-cell omics uncover gene dynamics shaping embryonic and extra embryonic lineages in pig blastocysts
No full textInternational audienceLate blastocyst development before implantation is a unique feature of ungulates, during which the epiblast proliferates and maintains pluripotency while extra-embryonic tissues expand dramatically, elongating to several tens of centimeters. The mechanisms coordinating these processes are not well understood. We performed single-cell omics profiling of porcine blastocysts from the hatched stage (E7) through early (E9) and late ovoid stages (E11). From 15,370 cells, we identified distinct embryonic and extra-embryonic populations with characteristic chromatin accessibility profiles. We reconstructed gene regulatory networks using enhancer-based eRegulons and validated them through motif occupancy analysis. Extra-embryonic tissues showed strong shifts in gene regulatory module activity at the onset of elongation, reflecting major transitions in morphogenesis and differentiation and the activation of pathways linked to cell morphology, proliferation, metabolism, trafficking, and biomolecule transport. In contrast, epiblast cells retained a stable transcriptional and regulatory identity from day 7 to day 11, immediately preceding the onset of gastrulation
Demonstrating Aeolus capability to observe wind-cloud interactions
No full textInternational audienceModel based studies have shown interactions between wind vertical profiles and cloudiness, but few observational studies corroborate them. The unique observations of Aeolus spaceborne Doppler wind lidar can contribute to fill this gap. In this paper, we merged global Aeolus observations of cloud profiles at full horizontal resolution (3 km along orbit track) with co-located profiles of horizontal winds.We first observed wind-cloud interactions at regional scale over the Indian Ocean. Aeolus captures the strengthening of the Tropical Easterly Jet in early June 2020, with wind speeds exceeding 40 m s -1 in its core, and a simultaneous increase of high cloud fraction up to above 30 %, until the decay of the jet during fall.Secondly, we observed wind-cloud interactions at cloud scale (between 3-100 km) in different regions. Over the Indian Ocean as well as over cumulus and stratocumulus dominated regions, we found that the wind shear inside clouds is smaller than the wind shear in the clear sky surrounding the clouds (statistically significant). In addition, we found that the wind speed difference between the cloud and its surrounding clear sky increases with the clear sky wind shear, especially in cumulus (R = -0.94) and stratocumulus (R = -0.87) dominated regions. This study demonstrated that despite its coarse resolution, Aeolus can capture wind perturbations induced by convective motion.</div
Magnetic Thomas-Fermi theory for 2D abelian anyons
No full textTwo-dimensional abelian anyons are, in the magnetic gauge picture,represented as fermions coupled to magnetic flux tubes. For the groundstate of such a system in a trapping potential, we theoretically andnumerically investigate a Hartree approximate model, obtained byrestricting trial states to Slater determinants and introducing a self-consistent magnetic field, locally proportional to matter density. This leads to a fermionic variant of the Chern-Simons-Schrödinger system. We find that for dense systems, a semi-classical approximation yields qualitatively good results. Namely, we derive a density functional theory of magnetic Thomas-Fermi type, which correctly captures the trends of our numerical results. In particular, we explore the subtle dependence of the ground state with respect to the fraction of magnetic flux units attached to particles
French-Speaking Network of Pharmacogenetics (RNPGx) Recommendations for Gene Panel Analysis Through Genotyping or Sequencing in Pharmacogenetics
No full textInternational audienceBACKGROUND: The implementation of pharmacogenetics in clinical practice increasingly relies on multigene panels. OBJECTIVES: The objective of this study is to develop harmonized recommendations for the design and analytical implementation of multigene pharmacogenetic panels, defining clinically relevant genes and associated regions of interest (ROIs) based on evidence strength, therapeutic applicability, and compatibility with genotyping or sequencing technologies. METHODS: The French-Speaking Network of Pharmacogenetics (RNPGx) evaluated 81 candidate genes across five therapeutic domains (i.e., oncology and supportive care, anesthesia and pain management, cardiology, neurology and psychiatry and immunology and infectious diseases) using a structured, evidence-based scoring system. Each gene was evaluated using a 25-point scoring system integrating pharmacogenetic importance, regulatory and professional society recommendations, and expert consensus. For the genes ultimately selected for the core panel, clinically relevant regions of interest were defined and assigned to one of three analytical classes. Class 1 includes variants with established clinical actionability; Class 2 adds optional variants suitable for extended testing in specialized settings; and Class 3 covers broader genomic regions mainly intended for rare variant or structural analyses. RESULTS: A 28-gene core panel was retained. Class 1 included 76 prioritized variants (including CYP2D6 CNV variants), and Class 2 comprised 62 additional variants (with extended analysis for CYP2D6). Class 3 eligibility was retained for 18 genes. CONCLUSION: The RNPGx recommendations offer a harmonized and flexible framework for pharmacogenetic panel design and for the extraction and interpretation of pharmacogenetic data from whole-exome or whole-genome sequencing
IA-bracadabra!
No full textLinkedinIl en est des technologies comme de la magie : elles créent toutes sortes de fantasmes. Depuis la mise à disposition de l’Intelligence Artificielle (IA) Générative auprès du grand public avec ChatGPT, l’IA est une de ces technologies à l’origine des discours les plus fantasques, les plus alarmistes ou les plus optimistes. Il y a dans ces discours une sorte de fébrilité et de passion qui me laisse, en tant que chercheuse en systèmes d’information depuis bientôt 30 ans, assez perplexe. Il y a là, pour moi, une forme de pensée magique, voire désidérative, et des positions souvent plus fondées sur des croyances que sur des faits réels et vérifiables
Characterization of extracellular vesicles at parturition in dairy cows with lategestation heat stress
No full textInternational audienceThis study investigated how late-gestation heat stress (HT) affects extracellular vesicle (EV) protein profiles in dairy cows at parturition. Plasma EV were isolated from heat-stressed and cooled (CL) cows and analyzed by mass spectrometry. A total of 684 proteins were identified, of which 20 differed significantly between treatments. The EV from cooled cows were enriched in extracellular matrix and coagulation proteins, including laminins, collagen IV, fibrinogen, and von Willebrand factor. The presence of these proteins in CL cows suggests that cooling enhances molecular pathways involved in tissue repair and postpartum recovery. Conversely, immunoglobulin-related proteins and specific receptors were reduced in cooled cows, potentially reflecting lower immune stress. These findings indicate that HT during late gestation alters EV-mediated signaling related to metabolism, immune modulation, and tissue remodeling at parturition. The identified proteins may serve as potential biomarkers for assessing maternal adaptation and recovery, emphasizing the importance of environmental cooling during the dry period. NTA = nanoparticle tracking analysis; trt = treatment.Highlights• Heat stress during late gestation significantly alters EV content.• Cooling increased extracellular matrix and coagulation proteins, perhaps for tissue repair and postpartum recovery.• Cooling decreased immunoglobulin-related proteins and certain receptors in EV.• Changes in EV proteins may reflect improved recovery and lower immune stress with cooling