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Convex cocompact groups in real hyperbolic spaces with limit set a Pontryagin sphere
No full textAccepted for publication in Bulletin of the London Mathematical Society.We exhibit two examples of convex cocompact subgroups of the isometry groups of real hyperbolic spaces with limit set a Pontryagin sphere: one generated by 50 reflections of , and the other by a rotation of order 21 and a reflection of . For each of them, we also locate convex cocompact subgroups with limit set a Menger curve
A novel cobalt metalloporphyrin-based electrochemical platform for ultra-sensitive vanillin detection in real food samples: Integrated experimental and theoretical approaches
No full textInternational audienceA new cobalt(II) porphyrin complex, [Co(TMFPP)(4-CNpy)]center dot 2/3 CHCl3 center dot 1/3 C6H14 (complex I), was synthesized and structurally confirmed by single-crystal X-ray diffraction, revealing a distorted square-pyramidal geometry. Electrochemical studies showed its strong performance as a vanillin (VAN) sensor, with wide linear ranges (1-100 mu mol and sdot;L- 1 and 250-500 mu mol and sdot;L- 1) and a low detection limit of 0.136 mu mol and sdot;L- 1. The sensor displayed excellent stability, selectivity, and real-sample applicability, achieving recovery rates of 90.6-104 % in food products. Complementary DFT and TD-DFT analyses supported the experimental findings, highlighting the complex's strong affinity for VAN. These results demonstrate the promise of cobalt(II) metalloporphyrins as efficient electrochemical sensors for food quality monitoring
Sitcoms, FASP et communautés de pratique : quelles cultures professionnelles enseigner en LEA ?
No full textInternational audienceCette communication s’inscrit dans la continuité des réflexions sur le rôle de la culture en anglais de spécialité et s’intéresse à l’enseignement de la culture professionnelle en licence LEA, formation caractérisée par sa transversalité et la diversité des parcours en master. Il s’agira ainsi d’interroger quelles cultures enseigner en LEA et comment articuler culture générale du travail et cultures spécialisées de domaine.Si la culture des milieux spécialisés dépasse la seule dimension lexicale, nous proposons d’explorer différentes ressources, de prime abord non spécialisées, exploitables en classe et organisées selon un spectre de spécialisation allant de représentations générales du monde du travail à celles de domaines particuliers. Les représentations issues des workplace sitcoms offrent une porte d’entrée vers des valeurs transversales de la culture d’entreprise, comme les relations hiérarchiques ou la gestion de conflits (Schneider, 2023). Ces supports, accessibles et familiers pour les étudiants, reflètent des évolutions sociétales et leur permettent, souvent en l’absence d’expérience directe, de se forger des repères culturels relatifs au monde professionnel (Bost, 2014, p. 2).À l’autre bout du spectre, des cultures spécialisées comme celle de la banque et des marchés financiers, que nous prenons en exemple, façonnent à la fois les comportements et les processus organisationnels. La culture y dépasse la seule notion d’éthique et structure l’embauche, le licenciement, la rémunération (Thakor, 2016, p. 13) ainsi que les opérations boursières (Grennan, 2020). La série télévisée Industry (Down & Kay, 2020), centrée sur de jeunes diplômés intégrant une banque d’investissement londonienne illustre comment la fiction à substrat professionnel (FASP) peut médier ces codes implicites et rendre visibles les rituels, valeurs et pressions propres à ce milieu.D’autres ressources, comme les messages publiés sur Reddit offrent également un accès indirect mais crédible à des communautés de pratique (Wenger, McDermott & Snyder, 2002) et à des occurrences de « consultation de l’expert » (Van der Yeught, 2022). La réflexion sur la culture professionnelle ne se limite donc pas à la dimension éthique mais concerne aussi l’ensemble des interactions autour de processus précis, et la langue sert d’artefact essentiel pour ce faire (Morrison & Shapiro, 2016).Ces ressources peuvent ainsi enrichir la formation des étudiants en LEA et contribuer au développement des compétences attendues en fin de diplôme, conformément au référentiel RNCP (France Compétences, 2025)
Long-term air pollution exposure and mental health in French adults of the CONSTANCES cohort: Role of black carbon independently of PM2.5
No full textInternational audienceAmbient air pollution could be associated with poor mental health. Black carbon (BC) has been highlighted as a crucial component of particulate matter; however, its isolated role independent from the total particulate matter mass has been poorly studied. Our study aimed to examine the associations between long-term exposure to particulate matter with a diameter <2.5 μm (PM2.5), BC and nitrogen dioxide (NO2) and psychological distress in the French CONSTANCES cohort and to assess the role of BC independently of PM2.5. This cross-sectional study included 104,146 adults. Psychological distress was assessed in 2019 using the General Health Questionnaire-12 (GHQ-12). Annual concentrations of PM2.5, BC, and NO2 estimated from land-use regression models at each participant's residential address. Negative binomial models with different covariate adjustments were used. A residuals method was used to assess the independent role of BC. Incident rate ratios (IRR) per an interquartile range (IQR) increase in exposure to each pollutant were calculated. Stratified analyses by age, sex, education and season were also conducted. Mean exposures were 9.38 μg/m3 for PM2.5 (IQR = 2.6), 1.15 × 10−5/m for BC (IQR = 0.5) and 19.1 μg/m3 for NO2 (IQR = 11.5). Exposure to each pollutant was significantly associated with higher psychological distress (IRR (95 % CI): 1.052 (1.014–1.092) for PM2.5, 1.078 (1.055–1.101) for BC, and 1.082(1.057–1.109) for NO2). Stronger associations were found for men, elderly, lower-educated, and during warm season. BC residuals were significantly associated with higher psychological distress when regressed on PM2.5 (1.055 (1.039–1.071)) and when regressed on NO2 (1.067(1.041–1.093)). Exposure to ambient air pollution was associated with psychological distress, with BC showing a deleterious role independently of PM2.5 and NO2
Shortcomings of Linear-Response TD-DFT for ESA Oscillator Strength Calculations
No full textInternational audienceWe present an evaluation of linear-response (LR) TD-DFT for the calculation of excited-state absorption (ESA) oscillator strengths. Specifically, we compare this approach with the computationally more expensive quadratic-response (QR) scheme, which we previously benchmarked, J. Chem. Theory Comput. 21 (2025) 4688, and analyze the deviations between the two approaches using various metrics. Three subsets of molecules and ESA transitions are considered: (i) subset A, a data set of 21 compact molecules comprising 53 ESA transitions, (ii) subset B consisting of 9 large molecules inspired by real-life fluorescent dyes, and (iii) subset C of selected molecules in their relaxed S1 geometries. For subset A, we identify a clear relationship between the single-reference character of the excited states involved in the ESA process and the magnitude of the QR-LR deviations. Additionally, we observe a significant correlation between the contribution of the TD-DFT de-excitation vectors, the single-reference character of one of the two excited states, and the QR-LR discrepancies. For both subsets B and C, the correlations observed in subset A are less pronounced. Nevertheless, the largest outliers consistently involve at least one state with strong de-excitation components. Finally, we propose a simple linear correction for the unrelaxed LR oscillator strengths. Overall, LR-TD-DFT tends to almost systematically overestimate ESA oscillator strengths, especially when one of the two excited states involved exhibits large de-excitation contributions
Geometric effects of hyperbolic cohomology classes on Kähler manifolds (with an appendix by Benoît Claudon)
No full textWe introduce the notion of Kähler topologically hyperbolic manifold, as a"topological" generalization of Kähler [Gro91] and weakly Kähler [BDET24] hyperbolic manifolds. Analogously to [BCDT24], we show the birational invariance of this property and then that Kähler topologically hyperbolic manifolds are not uniruled nor bimeromorphic to compact Kähler manifolds with trivial first real Chern class. Then, we prove spectral gap theorems for positive holomorphic Hermitian vector bundles on Kähler topologically hyperbolic manifolds, obtaining in particular effective non vanishing results à la Kawamata for adjoint line bundles. We finally explore the effects of Kähler topologically hyperbolicity on Ricci and scalar curvature of Kähler metrics. In the appendix, it is given an explicit description of degree~2 hyperbolic classes for finitely presented groups, and an algebro-geometric consequence for Kähler topologically hyperbolic surfaces: they are necessarily of general type
Inhibition of human organic anion transporter 4 (OAT4) activity by bisphenol analogues
No full textInternational audienceOrganic anion transporter (OAT) 4 is a kidney and placental membrane protein implicated in the transport of xenobiotics, including pollutants. The present study was designed to determine whether environmental bisphenol (BP) analogues, including emerging bisphenol A substitutes, can interact with OAT4. 6-carboxyfluorescein-related OAT4 activity displayed by OAT4-overexpressing HEK-293 cells was inhibited by 7/23 BP analogues used at 10 μM, especially by the thermal paper-contained color developer Pergafast® 201 (PF201) and the flame retardants tetrabromobisphenol A (TBBPA) and tetrachlorobisphenol A (TCBPA), acting in a concentration-dependent manner (with IC50 values in the 0.95-1.48 μM range). Most of these BP analogues moreover decreased membrane transport of estrone-3-sulfate, a hormonal endogenous substrate for OAT4. Some of them, especially PF201, additionally blocked activity of the renal transporters OAT1 and OAT3. Interaction of BP analogues with OAT4 was further supported by docking simulation studies, indicating that PF201 binds to the Arg473-containing electropositive pocket of OAT4, presumed to play a key role in inhibition of OAT4-mediated transport. BP analogues however failed to trans-stimulate OAT4 activity and OAT4-overexpressing cells exhibited no or marginally increased sensitivity to PF201, TBBPA and TCBPA, thus suggesting that these BP analogues are not or poorly transported by OAT4. In vitro to in vivo extrapolation finally demonstrated that occupational exposure to PF201 is predicted to result in human OAT4 inhibition. Overall, OAT4 was demonstrated to be a target for BP analogues, including BPA substitutes, with possible deleterious consequences in terms of OAT4-mediated transport of endogenous compounds or drugs, notably for workers exposed to PF201
Regulatory RNA Ern0160 controls Enterococcus faecium virulence through direct modulation of expression of LysM domain-containing proteins
No full textInternational audienceBackground: Enterococcus faecium is a commensal of the human gut microbiota that can become an opportunistic pathogen, particularly in immunocompromised individuals. Small RNAs (sRNA) are thought to contribute to this shift by enabling rapid bacterial adaptation to environmental changes. Despite this, knowledge of sRNA in E. faecium remains limited. Ern0160, in particular, has attracted interest for its involvement in antibiotic and biocide responses, as well as its role in intestinal colonization in a murine model.Results: In this study, we investigated the functions of Ern0160 in E. faecium Aus0004 reference strain and sought to identify its mRNA targets. Transcriptomic and in silico analyses revealed potential regulatory targets, including two homologous genes encoding LysM-containing domain proteins (EFAU004_01059 and EFAU004_01150), both associated with enterococcal pathogenicity. Experimental validation confirmed that increased expression of Ern0160 led to repression of these genes. We further demonstrated direct and specific interactions between Ern0160 and the two homologous target mRNAs. Functional assays in the Galleria mellonella larvae infection model showed that deletion of Ern0160 resulted in increased host mortality, whereas deletion of its targets genes resulted in decreased mortality. These results are consistent with previous findings linking these genes to E. faecium virulence in murine model of systemic and urinary tract infections.Conclusions: Our findings suggest that Ern0160 contributes to a regulatory network that modulates E. faecium colonization and infection by targeting genes involved in antimicrobial response and virulence. This study highlights the potential of regulatory RNAs such as Ern0160 to shape the pathogenic behavior of a multi-drug resistant and clinically significant bacterium
First-line [18F]F-choline PET/CT in primary hyperparathyroidism: a cost-effectiveness study from the diagnostic randomized APACH2 trial
No full textInternational audienceBackground: The randomized controlled multicentre APACH2 trial showed that first-line [18F]F-choline (FCH1) PET/CT is superior to [99mTc]Tc-sestaMIBI (MIBI1) SPECT/CT for referring patients with primary hyperparathyroidism (pHPT) to effective minimally invasive parathyroidectomy (MIP). The aim of this study was to weigh this clinical gain against the increase in imaging costs.Methods: The effectiveness criterion per imaging strategy was the rate of normocalcemia at one month post true-positive first-line imaging-guided MIP. The medico-economic analysis, carried out from the payer's perspective, integrated direct hospital costs up to 6 months after randomization. The result of the cost-effectiveness analysis was calculated in the form of an incremental cost-effectiveness ratio (ICER), establishing the average cost necessary to cure an additional person by switching from the usual MIBI1 strategy to the new FCH1 strategy. Sensitivity analyses were used to test the robustness of the ICER.Results: The APACH2 trial enrolled 57 patients from November 2019 to May 2022 in four centres, randomized between FCH1 (n = 29) or MIBI1 (n = 28). The differential cost between FCH1 and MIBI1 strategies was €136.5 (average cost FCH1 €3,843.5 (95% CI: 3442.5-4244.5) vs MIBI1 €3,707.0 (95% CI: 3606.9- 3807.6), p = 0.53), with a differential effectiveness of 29% (average effectiveness FCH1 85% (95% CI: 0.71-0.99) vs MIBI1 56% (95% CI: 0.36-0.76), p = 0.037). The ICER of FCH1 compared to MIBI1 was €471 for referring one additional patient to MIP followed by normocalcemia. Deterministic sensitivity analysis showed ICER to vary from €-567 to €1,507. The probabilistic sensitivity analysis showed the robustness of our finding that the FCH1 strategy is slightly more expensive but also more effective than the MIBI1 strategy.Conclusion: First-line FCH PET/CT in the surgical management of pHPT allows more patients to be referred directly to successful outpatient MIP at a minimal additional cost from a health insurance point of view