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Efficient Synthesis of Conformationally Constrained 5,5′-Bi-1,2,3-Triazole-Based Bis-Macrocycles
No full textInternational audienceWe report herein the synthesis and structural characterization of 5,5′-bi-1,2,3-triazole bis-macrocycles obtained via oxidative copper-catalyzed azide–alkyne cycloaddition (CuAAC) of acyclic precursors bearing azide and alkyne groups. Initially observed as by-products during the copper(I)-N-Heterocyclic Carbenes (NHCs)–catalyzed CuAAC synthesis of a 1,2,3-triazole–based macrocycle, these compounds were selectively obtained after systematic optimization of the catalyst, ligand, reaction atmosphere, and precursor addition rate. The bis-macrocycles were characterized by Nuclear Magnetic Resonance (NMR) and High Resolution Mass Spectrometry (HRMS), and in some cases, by single-crystal X-ray diffraction. Chiral High-Performance Liquid Chromatography (HPLC) experiments enabled enantiomer separation, confirming their configurational stability
Search for decays at LHCb
No full textInternational audienceA search for decays is performed using proton-proton collision data collected by the LHCb experiment at a centre-of-mass energy of , corresponding to an integrated luminosity of . No signals are found and upper limits are set for the first time on the branching fractions and , at the 90% confidence level
Agir localement, viser la transition: Arrangement et justifications des projets agricoles alternatifs aspirant à un changement d’échelle
No full textInternational audienceL’objectif de ce colloque est d’interroger, dans une perspective pluridisciplinaire, cette notion de « transition territoriale » – sa pertinence, ses utilisations et traductions, ses pistes de consolidation théorique ainsi que sa portée heuristique et transformatrice – dans un contexte de crises multiples, de fortes tensions sociopolitiques et géopolitiques et d’incertitudes sur le devenir des systèmes territoriaux. Comment penser, étudier, voire accompagner les transitions des territoires en contexte d’incertitudes et de tensions ? Organisé par l'UMR Territoires (https://umr-territoires.fr), ce colloque se déroulera du 24 au 26 novembre 2025 à Clermont-Ferrand (Maison des Sciences Humaines)
Réseaux sociaux, salle de sport, supermarchés : la révolution des protéines: 8e édition des rencontres MeatLab par Charal
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What ZTF Saw Where Rubin Looked: Anomaly Hunting in DR23
No full textInternational audienceWe present results from the SNAD VIII Workshop, during which we conducted the first systematic anomaly search in the Zwicky Transient Facility fields also observed by LSST commissioning camera during Rubin Scientific Pipeline commissioning. Using the PineForest active anomaly detection (AD) algorithm, we analysed four selected fields (two galactic and two extragalactic) and visually inspected 400 candidates. As a result, we discovered six previously uncatalogued variable stars, including RS CVn, BY Draconis, ellipsoidal, and solar-type variables, and refined classifications and periods for six known objects. These results demonstrate the effectiveness of the SNAD AD pipeline and provide a preview of the discovery potential in the upcoming LSST data
Étude prospective sur la prévalence et l’impact de la fatigue chez les patients myasthéniques suivis au CHU de Clermont-Ferrand : “My” asthénie
No full textObjectifs : évaluer la prévalence de la fatigue chez les patients atteints de myasthénie auto-immune suivis au CHU de Clermont-Ferrand, ainsi que son impact sur la qualité de vie et les facteurs cliniques et psycho-sociaux associés.Méthodes : étude observationnelle, prospective et monocentrique, réalisée entre février et mai 2025. Les patients inclus étaient majeurs, avec un diagnostic confirmé. Le recueil comportait une analyse rétrospective des dossiers médicaux et l’administration de questionnaires validés : Fatigue Severity Scale (FSS), Modified Fatigue Impact Scale (MFIS), Myasthenia Gravis-Activity of Daily Living (MG-ADL), Myasthenia Gravis Quality of Life-15 (MG-QoL-15), Hospital Anxiety and Depression Scale (HADS), Godin Leisure Time Exercise Questionnaire (GLTEQ) et Patient Acceptable Symptom States (PASS). Les analyses statistiques incluaient comparaisons univariées et régression logistique multivariée ainsi qu’une analyse en sous groupe chez les patients stables.Résultats : sur 163 patients identifiés, 92 ont été inclus (âge moyen 66.5 ans, 58.7 % d’hommes). La prévalence de la fatigue (FSS > 4) était de 57,6 % (IC95 % [46.9–67.9]) et celle de l’impact significatif de la fatigue (MFIS ≥ 45) de 75.0 %. La fatigue était associée à une altération de la qualité de vie (MGQoL-15 plus élevé), à une sévérité clinique accrue (MG-ADL, score de Garches), ainsi qu’à la présence d’anxiété et de dépression (HADS). Les patients non satisfaits de leur état clinique (PASS « Non ») rapportaient plus souvent une fatigue significative. En analyse multivariable, seule l’HADSD apparaît significativement indépendante (p = 0.04). Aucune association n’a été observée avec l’âge, les comorbidités, les traitements reçus ou la thymectomie. Des tendances non significatives suggèrent toutefois un rôle du sexe féminin, de l’excès pondéral et de la présence d’un SAHOS. Malgré une stabilité clinique, 40.4 % des patients de ce sous-groupe présentent une fatigue significative. Celle-ci peut être en lien avec un niveau d’activité physique plus faible.Conclusion : la fatigue est un symptôme fréquent et invalidant chez les patients myasthéniques, y compris chez ceux considérés comme stables cliniquement. Elle impacte fortement la qualité de vie et semble étroitement liée aux dimensions psychologiques. Ces résultats soulignent l’importance d’un dépistage systématique de la fatigue et de sa prise en charge multidimensionnelle, incluant un suivi psychologique et la promotion d’une activité physique adaptée
Fluorination: a smart approach to designing high-value sp³ carbon-based nanomaterials—diamane and ultrapure nanodiamonds.
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Dark septate endophyte Periconia macrospinosa enhances wheat seedling growth and mitigates Fusarium crown rot by reprogramming the host's immune responses
No full textInternational audienceFusarium crown rot (FCR) in wheat, caused by Fusarium graminearum, is among the world's major fusarium diseases. This study aimed to assess the potential of the dark septate endophyte Periconia macrospinosa PmVS01 in promoting wheat seedlings growth and inducing resistance against F. graminearum Fg1 under greenhouse conditions, as well as its ability to inhibit pathogen growth under axenic culture. The results demonstrated that P. macrospinosa PmSV01 enhances key plant ecophysiological traits, including photosynthetic activity (18 %), nitrogen nutritional status (18 %), and the accumulation of defensive flavonol compounds (22 %), which collectively result in average increase of 10 %-30 % in both root and shoot growth and biomass. These stimulating effects correlate with its symbiotic nature, as it colonizes the rhizodermis and peripheral parenchyma regions of the roots without causing morbid symptoms. It also significantly protects seedlings against FCR disease. Transcriptomic analyses by qPCR indicate that this protective effect is associated with its ability to enhance host immunity and to reprogram multiple metabolic processes involved in plant defense, including pathways related to oxidative and water stress responses, as well as jasmonic acid and salicylic acid signaling. In addition, confrontation assays revealed an antagonistic activity of P. macrospinosa PmSV01 against F. graminearum Fg1 through the production of diffusible and volatile compounds, leading to an inhibition rate of the pathogen's mycelia growth that ranges from 28 % to 85 %. This is the first report of the beneficial effect of P. macrospinosa PmSV01 on wheat and resistance to FCR, and provides new alternatives for exploiting the potential of DSEs as plant growth-promoting fungi and biocontrol agents for sustainable crop production
AstroGeoFit. A Genetic Algorithm and Bayesian Approach for the Astronomical Calibration of the Geological Timescale
No full textInternational audienceVariations in Earth's orbit and axial tilt induce climatic changes which are recorded in sedimentary deposits. The frequencies of these cyclical variations are integer combinations of the main secular frequencies of the solar system. Analyzing these cycles in sedimentary records can help establish an astronomical time scale for the geological record by correlating geological proxies with computed variations in insolation on the Earth's surface that follows the gravitational laws. When the astronomical solution becomes uncertain when going back in time, the analysis of stratigraphic records can provide insights into the past states of the planetary system and the evolution of the Earth-Moon system. A critical aspect of this analysis is the estimation of the sedimentary deposition rate, which determines the time-depth transfer function, relating geological depth to relative or absolute time. We propose a novel approach for constructing astronomical time scales for geological stratigraphic records. The AstroGeoFit method establishes a time-depth transfer function throughout the record, accommodating variable sedimentation rates, and extracts the primary astronomical signal from the geological sequence. This is achieved using a genetic algorithm that adapts to a wide range of sedimentation rate variations. This statistical analysis enables the reconstruction of an astronomical signal (e.g., eccentricity and/or precession) purely from the stratigraphic sequence with minimal subjective bias. When this template is correlated with an astronomical solution, an absolute time scale is obtained for the entire record. In addition, we show that uncertainties can be estimated at each stage of the AstroGeoFit process