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Symptoms and pathophysiology of post-acute sequelae following COVID-19 (PASC): a cohort study
No full textInternational audienc
Optimized Schwarz Methods in Time for Discrete Transport Control
No full textWe investigate optimized Schwarz domain decomposition methods in time for the control of the 1D transport equation. In the case of an internal control over the whole domain, the optimization problem can be transformed into a system of two coupled PDEs. We then apply the time-domain decomposition (without overlap) strategy on this PDE system as well as on its discretized counterpart. Under Fourier analysis, we analyse three different iterations: the fixed point iteration, the relaxed iteration and the preconditioned GMRES method. For each case, we propose parameters for the transmission conditions that lead to fast convergence of the method. We illustrate our results by numerical examples
Quantifier les risques : les conséquences sociales de la défaillance
No full textInternational audienc
L’analyse du discours francophone en Afrique de l’Ouest: Perspective historique et épistémologique
No full textLa contextualisation historique et épistémologique des disciplines est une préoccupation qui revient à intervalles réguliers dans les Suds, en Afrique notamment, sous la forme d’un appel pressant à la décolonisation des savoirs. Ce numéro, inscrit dans ce cadre politico-scientifique, vise à décrire l'histoire, la généalogie et les perspectives de l'analyse du discours dans la sous-région Ouest, tout en examinant ses enjeux épistémologiques. Ce faisant, il répond à une actualité en Afrique, marquée par la création du réseau R2AD en 2019 (Réseau africain d’analyse du discours), qui a stimulé l'intérêt pour structurer le champ de l'analyse du discours francophone, alors peu développé. La problématique centrale de ce dossier est l’urgence de la valorisation des savoirs endogènes, souvent minorés au profit de la « bibliothèque coloniale » témoignant de la domination de la recherche africaine par des institutions et chercheurs et chercheuses de l’Occident. Les auteurs et autrices y élaborent une cartographie de l’analyse du discours en Afrique de l’Ouest en examinant ses trajectoires théoriques (Aimée-Danielle LEZOU KOFFI), ses terrains et projets ouverts par la jeune recherche (Amadou Ouattara ADOU, Mian Gérard AYEMIEN, Nanourougo COULIBALY), et ses liens avec la sociolinguistique (Dorgelès HOUESSOU). Le numéro propose enfin une bibliographie raisonnée et commentée (Donald DJILÉ et Mireille Denise KISSI)
Restoring the common hamster’s farmland habitat—how crop associations might benefit Cricetus cricetus hibernation and reproduction
No full textInternational audienceBiodiversity decline is particularly pronounced in agricultural areas, where intensive farming practices have severely altered the ecosystems. In Alsace (France), this has led to the decline of the common hamster ( Cricetus cricetus ), a farmland-inhabiting hibernator. Previous work in laboratory conditions showed that diversifying the hamsters’ diet through crop association is a promising strategy to improve their hibernation and reproductive success. However, little is known about the effect of such crop associations in the wild. In this study, we monitored the hibernation behaviour (in laboratory cages) and reproductive success (in mesocosms) of hamsters exposed to four different crop associations of variable nutritional content, selected for their technical and economic benefits for farmers. Hamster hibernation behaviour depended mainly on the ingested energy and only marginally on the nutritional quality of the diet. Hamsters on lipid-rich diets showed a higher body mass before reproduction. All hamsters successfully reproduced in semi-natural conditions, even in wheat monoculture, where food supplements (weeds, invertebrates) prevented protein deficiencies. Associations richer in proteins and lipids such as legume-oleaginous crop mixes doubled reproductive outputs and increased pup growth. These results should help to improve hamster conservation measures and promote farmland biodiversity
Differences in the inflammatory response and corticoid responsiveness of human lung macrophages and parenchymal explants exposed to cigarette smoke extracts
No full textInternational audienceSmoking is the main cause of chronic obstructive pulmonary disease and is associated with corticosteroid resistance. Giventhe paucity of data on human lung preparations, macrophages (LMs) and parenchymal explants (LPEs) were exposed tocigarette smoke extract (CSE) in the presence or absence of lipopolysaccharide (LPS). Moreover, LMs and LPEs were treatedwith budesonide prior exposure to CSE or LPS. The levels of cytokines (TNF-α and IL-6) and chemokines (CCL2, CCL4,CXCL1, CXCL5, and CXCL8) in the supernatants were measured using ELISAs. In LMs, exposure to CSE for 24 h wasnot associated with significant difference in the production of cytokines and chemokines, with the notable exception of greaterCXCL8 production. The results were generally the same for LPEs. CSE exposure did not potentiate the LPS-induced productionof the cytokines and chemokines and even tended to reduce this production in LMs and LPEs. Lastly, CSE exposure inhibitedbudesonide’s anti-inflammatory activity in LMs but not in LPEs. The present results extend the literature data on thecigarette smoke’s in vitro inflammatory effects and its inhibition of corticosteroid efficacy in human lung preparations. Ourfindings question the relevance of these lung preparations with regard to the long-term toxicity of smoking and the corticosteroidresistance observed in smokers and in patients with COPD
Left ventricular ejection fraction and benefit of tricuspid valve interventions – insights from the international TRIGISTRY
No full textInternational audienceAims The impact of treatment for tricuspid regurgitation (TR) across different levels of left ventricular ejection fraction (LVEF) remains uncertain. This study aimed to compare the outcomes of surgical and transcatheter tricuspid valve interventions (TTVI) to conservative (medical) management across LVEF categories. Methods and results Patients with severe isolated TR from the TRIGISTRY, a multicentre international registry, were categorized based on LVEF (preserved ejection fraction [pEF]: ≥50%, mildly reduced ejection fraction [mrEF]: 41–49%, and reduced ejection fraction [rEF]: ≤40%). We assessed the impact of treatment modality and procedural success (mild‐to‐moderate or lower residual TR) on 2‐year survival within each LVEF category. Among 2384 patients, 1383 had pEF, 400 had mrEF, and 601 had rEF. Compared to conservative management, surgery ( p < 0.0005) and TTVI ( p < 0.0001) were associated with a survival benefit in patients with pEF. No significant survival advantage was observed in patients with mrEF ( p = 0.28 for both), nor in those with rEF ( p = 0.76 and p = 0.22, respectively). Similar results were obtained when surgical and transcatheter interventions were grouped ( p < 0.0001, p = 0.17 and p = 0.29 in patients with pEF, mrEF and rEF, respectively). Patients with residual TR after TTVI exhibited a trend toward worse survival compared to those managed conservatively across all LVEF categories ( p = 0.47, p = 0.33 and p = 0.008 in pEF, mrEF and rEF, respectively). Conclusions Transcatheter tricuspid valve intervention, whether surgical or transcatheter‐based, was associated with improved survival in patients with pEF but not in those with mrEF or rEF. Residual TR remained a significant prognostic factor across the entire LVEF spectrum. These findings highlight the need for careful patient selection when considering TTVI in individuals with rEF
Clinical features, treatment and outcomes of acute ethmoiditis: A case series of 20 hospitalized children
No full textInternational audienceWe described 20 children hospitalized with acute ethmoiditis between 2017 and 2022 in our center. Median age was 3.5 years, fifteen were Chandler’s group II and three were group III. Despite adequate antibiotic therapy regarding national antibiotic treatment guidelines, six (30 %) patients experienced poor outcomes; five of them required surgical drainage, reinforcing the need of close surveillance of these children
Automated Simultaneous Precise Time Calibration of White Rabbit Switches for REFIMEVE
No full textInternational audiencePrecise time and frequency signals are required for numerous applications including advanced scientific research such as High energy physics, Astronomy, Quantum telecommunications etc. In France, the national research infrastructure REFIMEVE distributes ultra-stable optical frequency reference signals over long distances for scientific applications. The reference signals are generated by the designated institute for time and frequency, LNE-OP, at Observatoire de Paris/LTE. They are distributed over the fiber-optic network of the national research and education network, RENATER, using bidirectional links over dark channels. REFIMEVE currently connects more than 30 research laboratories across France, and is also connected via cross-border links to National Physical Laboratory (NPL, UK), Physikalisch-Technische Bundesanstalt (PTB, Germany), Istituto Nazionale di Ricerca Metrologica (INRiM, Italy) and European Organization for Nuclear Research (CERN, Switzerland). In near future the network is planned to be extended to connect more than 40 French laboratories. T-REFIMEVE is a new and ongoing component of REFIMEVE, one major objective of which is to add time and microwave frequency references to the signals which are distributed, through the addition of a White Rabbit (WR) network to the infrastructure. We aim to achieve 10 ns-level time transfer accuracy over more than 80 interconnected WR nodes, over the 5000 km optical fiber network. The WR signals are transmitted as alien wavelengths on RENATER’s fibre network, using standard xWDM technology including unidirectional amplifiers, i.e. using unidirectional links. This introduces the challenge of compensating for the optical path asymmetries inherent to unidirectional links.A first key requirement of T-REFIMEVE is the accurate calibration of the instrumental delays of the White Rabbit Switches (WRS). This poster presents the calibration of dozens of WRS at LTE. We set up an independent calibration chain for T-REFIMEVE, based on unidirectional SFP transceivers at 1560.61 nm, and otherwise following the CERN calibration guidelines [2] and the EMPIR/VSL good practice guide [3]. Port 1 of a specific WRS was chosen as the Golden Calibrator of our chain, and its ingress and egress delays determined following [2]. This Golden Calibrator was then used to calibrate port 1 of a second WRS, thus creating a backup Golden Calibrator. The backup calibrator was then used to calibrate the remaining ports, 2 to 18, of the previous WRS, which we refer to as the Golden Calibrator WRS (as distinct from the Golden Calibrator port itself). This allows the Golden Calibrator WRS to be used to simultaneously calibrate 1 port each of many (up to 18) other WR switches. To calibrate the instrumental delays of more than 80 WRS efficiently, we developed an automated calibration bench for calibrating 10 switches simultaneously, by interfacing the WR switches under calibration with a datalogger containing an RF multiplexer, used to connect the PPS out signals of the WR switches successively to a single time interval counter. The programme developed to run the parallel calibrations borrowed heavily from CERN’s calibration code [4]. The PPS offsets both before calibration (i.e., using the CERN firmware default delays) and after calibration are measured when the ports of the Golden Master WRS are connected to the backup golden calibrator port. The initial synchronization was already good, with an average offset of 55 ps (σ_A=39 ps), which improved to -11 ps (σ_A=14 ps) after calibration.References:[1] O. Lopez et al., « Frequency and time transfer for metrology and beyond using telecommunication network fibres », Comptes Rendus Physique, vol. 16, no 5, p. 531 539, juin 2015, doi: 10.1016/j.crhy.2015.04.005.[2] G. Daniluk, “White Rabbit calibration procedure,” 2015 https://white-rabbit.web.cern.ch/documents/WR_Calibration-v1.1-20151109.pdf [3] Dierickx, Erik and X. Yan, “WR Good practice guide,” May 2019 https://gitlab.com/ohwr/project/white-rabbit/wikis/uploads/7df19b6a4d0e90bf6d7b8ae32b3b32c4/WR_Good_Practice_Guide.pdf [4] Link for the White Rabbit Switch Calibration Code provided by CERN: https://gitlab.com/ohwr/project/wr-switch-sw/-/tree/master/userspace/host_tools/calibratio