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Development of molybdenum doped cerium oxide passive counter electrodes by surfactant-assisted ultrasonic spray pyrolysis
No full textInternational audienceNumerous optoelectronic systems, such as electrochromic smart windows, require efficient counter electrodes for their functional operation. Herein, cerium oxide (CeO2) based layers are considered as optically-neutral compounds of high electrochemical activity. Their deposition as thin films onto conducting glass substrates is carried out via surfactant-assisted ultrasonic spray pyrolysis, while further considering heteroelement doping with molybdenum (0–10 %at.). Highly transparent and homogeneous films are accordingly produced, demonstrating important ion storage abilities, especially in the optimal case (6 %at. Mo), bearing a 28 mC cm−2 charging capacity, together with 90+% transmittance over a large optical range. Morpho-structural characterizations additionally highlight a high homogeneity in the deposited layers, owing to the presence of the surfactant species, and enhancing the transmittance of the films. Moreover, the substitution of Ce4+ ions by Mo6+ in the crystal lattice is shown to create additional oxygen vacancies in the layers, contributing to the observed increase in charging capacity. Altogether, excellent optical and electrochemical performances are obtained from such Mo-doped CeO2 formulations, surpassing most of the current related literature. Finally, proof-of-concept electrochromic devices, combining Mo-doped CeO2 optically-neutral electrodes with WO3 films and involving either liquid- or solid, gel-based electrolytes, display great performances of large optical contrasts, fast kinetics, and good coloration efficiencies.</p
Variation in aggressiveness plasticity between northern and southern European populations of Hymenoscyphus fraxineus , an invasive fungal pathogen of ash
No full textAbstract Hymenoscyphus fraxineus is an invasive fungal pathogen responsible for the ash dieback epidemic, which continues to cause severe mortality of common ash ( Fraxinus excelsior L.) across Europe. Following its likely introduction in northeastern Europe, the pathogen rapidly colonized most regions where common ash is present. As it spread southward, H. fraxineus encountered warmer climates and a greater occurrence of Fraxinus ornus L., a species largely resistant to the disease. Despite this environmental heterogeneity, which probably imposed adaptive challenges to H. fraxineus at the epidemic front, ash dieback continues to expand in southern Europe. Aggressiveness is a key life-history trait that is expected to evolve during epidemics and to exhibit plasticity in response to environmental variation. We investigated whether the plasticity of aggressiveness in response to temperature and ash species has evolved in H. fraxineus during its propagation towards southern Europe. Using a synchronic approach based on leaf inoculations, we characterized individual reaction norms for aggressiveness in a long-established Lithuanian population and a recently established Italian population of H. fraxineus . The Italian H. fraxineus population is exposed to warmer summers than the Lithuanian population, while F. ornus is present in Italy but absent in Lithuania. We observed no difference in the aggressiveness expressed on F. excelsior under moderate temperature between the two H. fraxineus populations. However, the ability of Italian isolates to cause severe leaf symptoms was less negatively affected by increasing temperature and host species change than that of Lithuanian isolates, suggesting local adaptation of H. fraxineus during its spread toward southern Europe. Our findings highlight the importance of considering the evolution of adaptive traits and their plasticity in fungal pathogens when anticipating disease risk. They also suggest that ash trees in southern Europe may be slightly more vulnerable to ash dieback than previously anticipated
Terrorizer: a novel algorithm for patent assignee name disambiguation
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Comprendre et suivre l’insécurité alimentaire en France : pour une meilleure garantie du droit à l’alimentation
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Management and survival of patients with cancer of unknown primary discussed by a French national multidisciplinary tumour board: a retrospective analysis
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Deciphering copper and zinc leaching from antifouling paints with different operating modes: flux determination and toxicity evidence
No full textInternational audienceLaboratory experiments were performed using 3 antifouling paints with different operating modes immersed in seawater for 7 days, to estimate copper and zinc fluxes and determine the scale of the related contamination. The toxicity of antifouling paints leachates was also assessed for natural bacterioplanktonic and phytoplanktonic communities. Given the increase in copper and zinc concentrations (4 to 1750-fold enrichment in dissolved Cu and to 7 to 200-fold enrichment in dissolved Zn), a systematic mortality upon phytoplankton was evidenced within 2 days of exposure to leachates produced from 1 hour to 2 days of immersion, whatever the paint. This went oppositely with the environmental risks calculated according to European guidelines, demonstrating an acceptable risk for the environment. Considering that 1 hour of leaching from a 7 cm² painted disk polluted 0.5L of seawater with Cu in our experimental conditions whatever the paint used, we estimated that a painted ship hull of 15 m² can pollute more than 10 m 3 of seawater within the same time. Leachates produced after only 20 minutes even yielded phytoplankton growth inhibition or mortality for insoluble and self-polishing paints, respectively, shortening the time needed for a freshly painted ship hull of 15 m² to pollute 10 m 3 . The bacterioplanktonic community appeared less sensitive than phytoplankton but demonstrated the same hierarchy: the highest toxicity was observed for the insoluble matrix and the lowest toxicity for the soluble one. This study therefore brings added value in terms of biocides flux determination, range of studied paints and concrete toxicity evaluation
Observatoires et techniques d’observation dans les sciences astronomiques (XVIIe-XVIIIe siècle)
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Diagonals and algebraicity modulo : a sharper degree bound
No full textTo appear in the Annales scientifiques de l'École normale supérieure. A longer version of this work is available at https://arxiv.org/abs/2306.02640International audienceIn 1984, Deligne proved that for any prime number , the reduction modulo of the diagonal of a multivariate algebraic power series with integer coefficients is algebraic over the field of rational functions with coefficients in . Moreover, he conjectured that the algebraic degrees of these functions should grow at most polynomially in . In this article, we provide a new and elementary proof of Deligne's theorem, which yields the first general polynomial bound on with an explicit and reasonable degree.En 1984, Deligne a montr\'e que pour tout nombre premier~, la r\'eduction modulo de la diagonale d'une s\'erie formelle alg\'ebrique de plusieurs variables \`a coefficients entiers est alg\'ebrique sur le corps des fonctions rationnelles \`a coefficients dans . De plus, il a sugg\'er\'e que les degr\'es d'alg\'ebricit\'e de ces fonctions devaient cro\^itre au plus polynomialement en fonction de . Dans cet article, nous pr\'esentons une nouvelle preuve du th\'eor\`eme de Deligne qui est \'el\'ementaire et permet d'\'etablir la premi\`ere borne g\'en\'erale polynomiale avec un degr\'e raisonnable
Generation and modulation of fully circularly polarized ultrabroadband THz radiation using two-color gas plasma techniques
No full textInternational audienceTerahertz optics enables powerful spectroscopy and imaging thanks to its non-ionizing nature and sensitivity to molecular and material properties. It is also beneficial to next-generation communications, since it offers vast bandwidth for ultra-fast, low-latency data transfer. Polarization control of terahertz waves is vital for applications in chiral spectroscopy, spin dynamics, ultrafast material studies, and communication multiplexing. Despite progress, full polarization control—particularly for ultra-broadband terahertz pulses—remains a challenge. In this work, we introduce a simple method for generating circularly polarized terahertz radiation with an ellipticity of 0.99. By optimizing key parameters—BBO crystal tilt, rotation, position, and pump chirp—we achieve broadband circular polarization across 30 THz, with indications of further extent to 40 THz. This approach advances fundamental studies in terahertz optics and paves the way for adaptive sensing and next-generation terahertz communications
Evaluation of cerebrospinal fluid penetration of delafloxacin in a murine model
No full textInternational audienceCerebrospinal fluid (CSF) penetration of delafloxacin was evaluated in a murine model. Mice received a single 40 mg/kg intraperitoneal dose. Plasma and CSF samples were collected at five time points over 4 h and analyzed by ultra high-per formance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS). Pharmaco kinetic parameters, including CSF penetration ratio (AUC 0-4h CSF/AUC 0-4h plasma), were determined using a non-compartmental model. The CSF penetration ratio of delaflox acin was 49%. Cmax/MIC ratios met pharmacokinetic/pharmacodynamic targets for Staphylococcus and Streptococcus spp., but not Enterobacterales. KEYWORDS delafloxacin, pharmacokinetic, cerebrospinal fluid D elafloxacin is a fourth-generation fluoroquinolone available in Europe since 2019(1). According to the literature, fluoroquinolones generally exhibit favorable penetration profiles into CSF (2). Pea et al. reported a cerebrospinal fluid (CSF)/plasma AUC ratio of 0.71 for levofloxacin in patients with external ventricular drains (3). For ciprofloxacin, CSF penetration ranges from 0.24 to 0.43 in noninflammatory conditions and can reach up to 0.9 in the presence of meningeal inflammation (4). Moxifloxacin also demonstrates favorable CSF penetration, with CSF/plasma ratios ranging from 0.46 to 0.9 depending on the presence of inflammation (5, 6). The physicochemical properties of delafloxacin (low molecular weight, moderate lipophilicity), its broad antimicrobial spectrum, and enhanced activity in acid environments make it a promising candidate for the treatment of central nervous system (CNS) infections. However, no data are currently available regarding the penetration of delafloxacin into the CNS. The aim of this study is to evaluate the penetration of delafloxacin into the CSF of mice. METHODS AnimalsFemale C57BL/6J mice aged 12 weeks were used (n = 15). Euthanasia was performed by cervical dislocation. ChemicalsDelafloxacin was provided by Menarini (QUOFENIX). Delafloxacin powder was reconstitu ted with 0.9% NaCl and then diluted to obtain a solution with a concentration of 5 mg/L. CSF and blood samplingAnalgesia was obtained by subcutaneous injection of buprenorphine (0.05 mg/kg) 30 min before sampling. Mice were anesthetized with isoflurane (3% induction and 1% maintenance) (Virbac Schweiz, Glattbrugg, Germany) during blood and CSF sampling. For CSF sampling, the neck skin was incised, and muscles were dissected to expose the cisterna magna. CSF samples were collected from region 5 of the cerebellum/spinal cord</div