Publications scientifiques de l'Université de Reims Champagne-Ardenne
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The Effect of Physico-Chemical Properties Obtained by Different Preparation Methods on CoCuAl Oxide for CO<sub>2</sub> Purification of Industrial Flue Gas
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Simulation des feux de biomasse et de leurs effets atmosphériques : une étude avec WRF-Chem
No full textInternational audienceIn the Southern Hemisphere, regions in South America are recognized as significant sources of carbonaceous aerosols, which are produced by biomass burning. This type of burning typically occurs during the winter months, predominantly in the region known as the "Deforestation Arc," often associated with the expansion of agricultural and livestock production areas in Brazil. Given the limited number of observations in this region, numerical modeling becomes essential for analyzing and accurately representing biomass burning events. In this context, the purpose of this study is to discretize the atmospheric behavior during fire events across South America by utilizing the Weather Research and Forecasting with Chemistry (WRF-Chem) model, thereby assessing the impact of these carbonaceous aerosols on cloud microphysics throughout the region. For this study, WRF-Chem version 4.3.1 was employed. The simulation began on September 28, 2007, and ended on October 3, 2007, using ERA5 fields to provide the initial and boundary conditions with a spatial resolution of 0.25°. The domain covered the South American region. Two simulations were conducted: the first, referred to as the control simulation (CTRL), had the coupling between aerosols, radiation, and cloud microphysics turned off, while the second, the fully coupled simulation (CPL), enabled both couplings. This approach facilitates a subsequent analysis to distinguish the role of aerosols on radiative properties and quantify the effects of coupling. For the analysis, precipitation fields, radiation components, and hydrometeor composition were evaluated in both simulations. This approach provides insights into the influence of biomass-burning aerosols on atmospheric processes and their role in modifying cloud microphysics and radiative balance.Dans l'hémisphère Sud, certaines régions d'Amérique du Sud sont reconnues comme d'importantes sources d'aérosols carbonés, produits par la combustion de biomasse. Ce type de combustion se produit généralement durant les mois d'hiver, principalement dans la région connue sous le nom d'« Arc de déforestation », souvent associée à l'expansion des zones de production agricole et d'élevage au Brésil. Compte tenu du nombre limité d'observations dans cette région, la modélisation numérique est essentielle pour analyser et représenter avec précision les feux de biomasse. Dans ce contexte, cette étude vise à discrétiser le comportement atmosphérique lors d'incendies en Amérique du Sud à l'aide du modèle WRF-Chem (Weather Research and Forecasting with Chemistry), afin d'évaluer l'impact de ces aérosols carbonés sur la microphysique des nuages dans toute la région. Pour cette étude, la version 4.3.1 de WRF-Chem a été utilisée. La simulation a débuté le 28 septembre 2007 et s'est terminée le 3 octobre 2007, en utilisant les champs ERA5 pour fournir les conditions initiales et aux limites, avec une résolution spatiale de 0,25°. Le domaine d'étude couvrait l'ensemble de l'Amérique du Sud. Deux simulations ont été réalisées : la première, dite simulation de contrôle (CTRL), désactivait le couplage entre les aérosols, le rayonnement et la microphysique des nuages, tandis que la seconde, la simulation entièrement couplée (CPL), activait les deux couplages. Cette approche facilite une analyse ultérieure visant à distinguer le rôle des aérosols sur les propriétés radiatives et à quantifier les effets du couplage. Pour cette analyse, les champs de précipitations, les composantes du rayonnement et la composition des hydrométéores ont été évalués dans les deux simulations. Cette approche permet de mieux comprendre l’influence des aérosols issus de la combustion de biomasse sur les processus atmosphériques et leur rôle dans la modification de la microphysique des nuages et du bilan radiatif
Simultaneous Abdominal Wall Reconstruction and Panniculectomy in High-Risk Complex Patients: A Retrospective Cohort Study
No full textInternational audienceIntroduction Ventral hernia repair (VHR) in high-risk, complex obese patients often presents a technical challenge for surgeons. Performing a panniculectomy (PAN) at the same time as the VHR may be an acceptable option for enhancing hernia exposure, improving cosmetic outcomes, and improving subsequent quality of life (QoL). However, this approach remains controversial due to the theoretical increase in postoperative complications. The objective of this study was to evaluate the relevance of combining PAN with VHR in complex obese patients in a specialised centre in France. Materials and Methods A retrospective single-arm study was conducted, including all patients who underwent VHR with PAN from January 2020 to December 2024 at a high-complexity referral hernia centre in Reims, France. Preoperative, intraoperative, and postoperative data were collected and analysed. Complications were categorised according to the Surgical Site Occurrences (SSOs), Surgical Site Infections (SSIs) and Clavien-Dindo classifications. Emergency hernia repairs were excluded. Results A total of 45 patients were included. The maximum median BMI was 40.26 kg/m 2 . All patients had at least one comorbidity, more than half had a loss of domain or a stoma, and more than 70% were classified as 2 or 3 according to the VHWG classification. The component separation technique was necessary for 42% of patients. The SSO and SSI rates were 58% and 7%, respectively, with an unplanned reoperation rate of 15%. After a median follow-up of 31 weeks, 11% of patients developed a hernia recurrence. Conclusion Combining PAN with VHR in complex obese patients increases the risk of minor wound complications but does not significantly affect the rate of major complications or recurrence. PAN may introduce additional morbidity for complex VHR in obese patients and should be considered in selected cases after a thorough risk-benefit evaluation
Evidence-Based Data Fusion for Robust Autonomous Vehicle Perception
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Filtre logique et Théorie du Contrôle Supervisé
No full textInternational audienceFiltre logique et Théorie du Contrôle Supervis
Travailler ensemble ? Réflexions autour de la création d’un collectif de recherche : le cas du Collectif MediSJeu
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Etude du comportement à l’arrachement des interfaces fibre/matrice: Etude du comportement à l’arrachement des interfaces fibre/matrice
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Conversion during Minimally Invasive Left Pancreatectomy: a nationwide study of causes and consequences
No full textInternational audienceObjectives: To identify risk factors for conversion, develop a predictive Conversion Risk Score (CRS), and assess the association between conversion and severe postoperative complications. Background: Conversion occurs in 15-30% of minimally invasive left pancreatectomies (MILP). Risk factors and potential negative impacts on postoperative outcomes are poorly described. Methods: Retrospective, nationwide, multicenter study including all MILP (laparoscopy and robot) performed between 2010 and 2021. Risk factors for conversion were identified by multivariate mixed model, and a CRS was developed on a “training-set” and validated (calibration diagrams and ROC curves) on a “validation-set.” The association between severe complications and conversion was assessed using a propensity score based on the main risk factors for severe complications: age, sex, BMI, ASA score, tumor malignancy, multi-organ resection, operative duration, blood loss, splenectomy. Results: 2104 patients included from 55 centers. Conversion occurred in 15.6% of MILP. Its risk factors were male sex (OR=1.67; P =0.048), BMI≥25 kg/m 2 (OR=2.15; P =0.004), history of laparotomy (OR=2.9; P <0.001), initial pancreatitis (OR=3.58; P =0.007), tumor size≥40 mm (OR=2.12; P =0.003), planned splenectomy (OR=2.63; P <0.001), unplanned splenectomy (OR=4.05; P =0.028), portal vein resection (OR=36.3; P =0.002), multi-organ resection (OR=12.97; P <0.001). A predictive CRS was created based only on preoperatively available variables (the first six), with scores ranging from 0 to 7, corresponding to a conversion risk of 2% to 100%. No association was observed with tumor malignancy, robotic approach, or pancreatectomy volume. Conversion was significantly associated with severe complications [OR=1.80(1.16-2.54)], independent of other risk factors for complications. Conclusions: Conversion during MILP can be predicted by CRS, aiding surgeons in decision-making, given its significant association with severe complications
Resistance to Antileishmanial Drug Candidates: A Flowchart for an Early Phenotypic Evaluation of Risk
No full textInternational audienceBackground: Drug development for leishmaniases treatment follows a very selective process in order to propose drug candidates that possess all the qualities that meet the strict specifications of the pharmaceutical industry. Drug resistance is a limiting factor that can impact the lifespan of a marketed drug. It is now essential that the risk of drug resistance be evaluated at the early stage of in vitro studies to discard a lead compound that could quickly generate drug resistance once available on the market. Objectives: This article aims to estimate the risk of drug resistance emergence for a promising drug candidate at the in vitro early stage of drug development. Methods: A sequential method is proposed to study some of the phenotypic characteristics and parameters of resistant parasites such as time to achieve maximal resistance during stepwise drug pressure, resistance amplitude, stability, fitness, and infectivity both in vitro and in vivo. Results: Some examples with drugs in clinical use and former drug candidates are given. Conclusions: This method providing an evaluation of the risk of drug resistance from an in vitro model of Leishmania donovani be extrapolated to other Leishmania species
Collaborative bottom-up Trust Missions: a perspective on long-term strategies with and for people and Nature
No full textInternational audienceThe environmental and climate crises are linked to rising global inequity. Because of its centrality in the living Earth, the Ocean represents a unique opportunity to restore equity, engaging society through harmony with Nature. The United Nation’s Ocean Decade and European Union’s Mission Ocean and Waters recognize this centrality, but have focused on top-down actions. Here, we advocate for collaborative Trust Missions, aimed at empowering citizens through networking and bottom-up transformative actions