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Dust pollution substantially weakens the impact of ammonia emission reduction on particulate nitrate formation
No full textInternational audienceDust emissions significantly influence air quality and contribute to nitrate aerosol pollution by altering aerosol acidity. Understanding how dust interacts with ammonia emission controls is crucial for managing particulate nitrate pollution, especially in urban areas. In this study, we conducted field measurements of aerosol components and gases across three cities in Eastern China during the spring of 2023. By combining an aerosol thermodynamic model with machine learning, we assessed the contribution of dust to aerosol pH and its impact on nitrate formation. Our results show that changes in ammonia, both in the gas and particle phases, were the main factors affecting aerosol pH, with dust particles contributing to about 7 % of the total pH variation. During dust events, high concentrations of non-volatile ions increased aerosol pH, leading to higher nitrate levels in particulate form. Machine learning analysis revealed that extreme dust storms caused a significant change in aerosol pH, enhancing nitrate partitioning. Further simulations indicated that while reducing ammonia emissions is effective in lowering nitrate levels under normal conditions, this effect is significantly reduced in dust-affected environments. Dust particles act as a buffer, reducing the sensitivity of nitrate formation to ammonia emission reductions. These findings emphasize the need to consider dust pollution when designing strategies for controlling particulate nitrate levels and highlight the complex interactions between dust and anthropogenic emissions
Characterization and Related Factors of Postural Control in Adults With Late-Onset Pompe Disease: Cross-Sectional and Case Control Study
No full textInternational audienceAbstract Importance Adults with late-onset Pompe disease (LOPD) experience lower limb weakness, balance disorders, and recurrent falls. Mechanisms underlying postural control (stability, orientation) and falls in LOPD remain poorly understood. Investigating these aspects is critical to guide care and rehabilitation. Objective This study compared postural control in participants with LOPD to controls, examining postural and muscular factors linked to falls and muscular contributions to postural alterations. Design This study was a cross-sectional, case–control study. Postural stability and orientation during stationary standing were evaluated using force platforms and 3D motion analysis under 2 visual conditions, while maximal muscle strength was measured with an isokinetic dynamometer. Setting This cross-sectional, case–control study was conducted at a teaching hospital, which was a reference center for neuromuscular disease. Participants This study involved 2 cohorts: participants with LOPD and control participants. Main Outcomes and Measure Postural stability (center of pressure: COP displacements, lower limb joint range of motion) and orientation (COP mean position, weight distribution, joint positions) parameters were assessed, alongside falls reported over 3 months and maximal lower limb muscles strength. Results Compared to 20 controls, 18 adults with LOPD showed impaired postural stability, especially medio-laterally with eyes closed (ES = 0.42–0.83), and an anterior shift of the COP without joint orientation changes. Falls were strongly associated with COP mean velocity (eyes open: ρ = 0.73; eyes closed: ρ = 0.74) and with hip abductor (ρ = − 0.77) and extensor strength (ρ = − 0.79). Hip extensor strength was most strongly associated with COP mean velocity (eyes closed: ρ = − 0.72; eyes open: ρ = − 0.69). Conclusions Adults with LOPD demonstrate impaired postural stability, especially in the medio-lateral plane with eyes closed, and an anteriorized upright orientation. Relevance Hip extensor and abductor strength, strongly linked to falls and stability, should be important to target in evaluations and rehabilitation and in studies on new therapies on LOPD
« Il y a un enjeu très fort aujourd’hui à repolitiser le monde associatif, non pas dans des discours, mais à partir de la question du travail ». Entretien avec Matthieu Hély et Maud Simonet
No full textInternational audienceEntretien avec Matthieu Hély et Maud Simonet, directeurs de l’ouvrage collectif Monde associatif et néolibéralisme paru aux PUF en 2023 (collection « La vie des idées », réalisé par Régis Guyon et Francis Lebon en juin 202
Comparison Between Clinical Outcomes in Influenza A and B Infections: A Multicenter Retrospective Cohort Study
No full textInternational audienceObjectivesInfluenza significantly contributes to seasonal morbidity and strains healthcare resources, yet data directly comparing types A and B remain limited. This study assesses potential differences in clinical severity and outcomes between these two influenza types.MethodsWe conducted a multicenter retrospective study of adult patients diagnosed with either influenza A or B. Using logistic regression, we identified predictors of adverse outcomes across demographics, comorbidities, and clinical parameters.ResultsThe influenza A and B cohorts included 234 and 113 patients, respectively. In comparison to influenza B, influenza A patients were more likely to receive oseltamivir (43.5% vs 27.9%, p = 0.01) and showed similar rates of radiological abnormalities (27.8% vs 24.8%, p = 0.6). Age ≥65 years remained the strongest predictor of hospitalization (aOR 4.78, p = 0.01). Predictors of ICU admission included age<65 (aOR 3.18, p = 0.02), radiological bilateral involvement (aOR 19.4, p < 0.001), receiving oseltamivir treatment (aOR 2.43, p = 0.01) with a trend towards documented superinfection (aOR 2.56, p = 0.07). Short-term favorable outcomes were more common in influenza B (aOR 2.52, p = 0.02), whereas chronic respiratory disease and Charlson comorbidity index reduced likelihood of favorable outcomes (aOR 0.34, p = 0.04 and 0.25, p = 0.001, respectively). Kaplan-Meier survival curves revealed similar mortality rates at 90 days between influenza A and B types (13.4% vs 8.7%, p = 0.3).ConclusionInfluenza type A and B exhibit distinct clinical trajectories and influenza B should not be neglected. These findings underscore the need for earlier diagnosis testing to promote earlier antiviral initiation and broader vaccination policies tailored to both influenza types
Statistical behavior of temporally compounding multi-peak flood events
No full textInternational audienceFloods are the most frequent natural hazard globally (2003-2023) and rank second in economic losses, according to EM-DAT, the International Disaster Database. When flood events occur in close succession, they pose significant challenges for emergency management due to limited recovery time between events. This study focuses on multi-peak (MP) floods, where peaks occur within hours to days. Using discharge data from 77 hydrometric stations in Northern Italy's Po district, we examined statistical differences between MP and single-peak (SP) flood events and analyzed their seasonal patterns and generating mechanisms across diverse river regimes. We demonstrated that SP and MP events exhibit distinct statistical behaviors. The first type of events has more skewed distributions with heavy tails, while the second displays flatter distributions with lighter tails and higher mean values. Seasonal analyses suggest that MP floods in glacial and nival-pluvial regimes are influenced by glacier and snow melting, whereas those in the Padanian regime are driven by tributary routing effects. These triggering mechanisms seem to be responsible of the lighter tails of the distribution of MP floods. By highlighting the distinct statistical behaviors and generating mechanisms of MP and SP floods, we identified recommendations for designing MP flood hydrograph, supporting flood-risk management.</div
Validation of POD24 as a robust early clinical indicator of poor survival in mantle cell lymphoma from 1280 patients on clinical trials, a LYSA study
No full textInternational audienceIn mantle cell lymphoma, early progression of disease has been associated with short overall survival. The impact of clinical, pathological, and treatment strategies on the risk of early relapse has not been assessed in a large cohort of patients. We performed a pooled analysis of patients recruited in France from six randomized first-line MCL trials. Among 1386 treated MCL patients, 1280 were evaluable for POD24 status: 299 (23.4%) with a POD24 event and 981 (76.6%) without. Patients with a POD24 event had a median OS of 9.3 months (95% CI 8.4-11.8) versus not reached (95% CI 97.8-NR) for those without POD24 events. The median post-relapse OS of patients with a late relapse was also significantly longer at 49.4 months (HR = 0.39; 95% CI 0.31-0.48; P < 0.001) as compared to POD24 patients. Baseline variables (age, performance status, B symptoms, LDH/ULN, leukocytes, blastoid variant, and Ki-67 > 30%) were significantly associated with the risk of POD24, independent of ASCT. Among responding patients at end-of-induction (n = 1105) who had received ASCT, anti-CD20 maintenance was associated with a decreased risk of POD24 (OR = 0.37; 95% CI 0.1-1.0). Using this large data set of patients in clinical trials, we confirm that POD24 status is strongly associated with subsequent OS in MCL. Rituximab maintenance provided significant protection against the risk of POD24, independent of ASCT. Progression within 2 years should be considered as a primary endpoint in future studies
Scientific objectives and instrumental requirements of the infrared spectrometer VenSpec-H onboard EnVision
No full textInternational audienceOnboard the EnVision spacecraft, there will be a suite of three spectrometers, VenSpec. One of these is called VenSpec-H where the H stands for high spectral resolution. Its scientific objectives consist of measuring variations of minor species' abundances in the atmosphere of Venus. H2O, SO2, CO, and OCS will be measured to characterize the potentially ongoing volcanic activity. These observations will allow us to understand both the importance of volatiles in volcanic activity on Venus and their effect on cloud maintenance and dynamics. VenSpec-H will measure these molecules in nadir viewing geometry, in infrared transparency windows of Venus' nightside to probe the troposphere, and in infrared spectral ranges on the dayside to measure the mesosphere. The scientific requirements enabling our scientific objectives will be demonstrated. The molecular vertical profiles, the aerosols' model, and the CO2 continuum contribution were established based on the literature for the different spectral windows. This enabled us to determine the spectral bands, their bandwidth, and the resolving power necessary for our purposes. Along the way, we identified possible improvements and science avenues. Some of them impact the instrument design, such as the need for polarimetric measurements. Others are related to remaining uncertainties in the model and laboratory measurements that will complement the investigation. This has been presented as a poster at the SPIE Optical Engineering + Applications Conference in August 2024 in San Diego, California, United States
Modelling of atmospheric variability in gas and aerosols during the ACROSS campaign 2022 of the greater Paris area: evaluation of the meteorology, dynamics and chemistry
No full textInternational audienceUnderstanding the interaction of anthropogenic and biogenic emissions around large urban agglomerations remains an important question for atmospheric research and the key question of the ACROSS (Atmospheric Chemistry of the Suburban Forest) project. ACROSS is based on an intensive field campaign in the Paris area, including ground-based measurements in the urban inner centre and suburban and forested sites and measurements made on board aircraft, during the exceptionally hot and dry summer of 2022. In addition, 3D modelling represents an important tool in ACROSS, and here we use the available measurements from the campaign together with observations from air quality and meteorological networks to evaluate the WRF–CHIMERE model simulation for the ACROSS period. We find that the WRF model is able to reproduce the meteorological variability during the campaign, in particular during two heatwaves. The model reproduces the daily ozone maxima well but overestimates PM2.5 by a factor of 1.5–2, partly due to an overestimation of secondary aerosol, both organic and inorganic. For organic aerosol in the Île-de-France area, the biases are reduced to about ±20 %. These differences are in contrast with those of the existing literature and might have been increased by the hot conditions of summer 2022. For case studies during two heatwave days, the model shows the sources for two organic aerosol peaks above 20–30 µg m−3, on one occasion due to biogenic secondary organic aerosol formation in different forests around Paris and on another occasion due to the advection of wildfire aerosols in combination with secondary formation mainly from forest-emitted biogenic volatile organic compounds (BVOCs)
Sexually transmitted infections and bacterial vaginosis in women of child-bearing age in Antananarivo, Madagascar: prevalence and risk factors from a cross-sectional study
No full textInternational audienceBackground :Recent data on sexually transmitted infections (STIs) and bacterial vaginosis (BV) in the general population of Madagascar is scarce. Our objective is to estimate the Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Trichomonas vaginalis (TV), Mycoplasma genitalium (MG), and BV prevalence among women and to determine associated risk factors.Methods :We recruited women aged 18–45 years consulting at a hospital in Antananarivo in a cross-sectional study. We collected socio-demographic and behavioral data. Vaginal swabs were collected for each individual. STIs were detected by qPCR and BV using the Nugent score. We explored factors associated with having an STI using logistic regressions.Results :Of the 501 recruited women, 242 (48%) were married. Only one woman in three ever used condoms. The prevalence of CT was 11.8% (95% Confidence Interval: 9.0, 14.6), NG: 4.2% (2.4, 5.9), TV: 14.8% (11.7, 17.9), MG: 8.2% (5.8, 10.6), and BV: 39.6% (35.3, 43.9). Factors associated with an STI were having sex in exchange for favors (adjusted Odds Ratio (aOR): 4.25, 95%CI: 1.27, 16.6), BV (aOR: 2.14, 95%CI: 1.34, 3.47) or intermediate vaginal microbiota (aOR: 2.10, 95%CI: 1.19, 3.72), and being in a non-marital relationship compared to married (aOR: 1.86, 95%CI: 1.16, 2.98).Conclusions :To address the high prevalence of STIs, prevention programs should target women who are more likely to engage in sex in exchange for favors and empower them with negotiation skills on condom use. Given the elevated prevalence of dysbiosis and its association with STIs, it is crucial to prioritize research efforts toward a comprehensive understanding of this relationship
Inadequacies in the representation of sub-seasonal phytoplankton dynamics in Earth system models
No full textInternational audienceSub-seasonal phytoplankton dynamics on timescales between 8 d and 3 months significantly contribute to annual fluctuations, making it essential to accurately represent this variability in ocean models to avoid distorting long-term trends. This study assesses the capability of Earth system models (ESMs) participating in the Coupled Model Intercomparison Project Phase 6 (CMIP6) to reproduce subseasonal surface ocean phytoplankton variations observed in ocean colour satellite data. Our findings reveal that, unlike sea surface temperature, all models struggle to accurately reproduce the total surface ocean phytoplankton variance and its decomposition across sub-seasonal, seasonal and multi-annual timescales. Over the historical period, some models strongly overestimate sub-seasonal variance and exaggerate its role in annual fluctuations, while others underestimate it. Our analysis suggests that underestimation of sub-seasonal variance is likely a consequence of the coarse horizontal resolution of CMIP6 models, which is insufficient to resolve mesoscale processes -a limitation potentially alleviated with higher-resolution models. Conversely, we suggest that the overestimation of sub-seasonal variance is potentially the consequence of intrinsic oscillations such as predator-prey oscillations in certain biogeochemical models. ESMs consistently show a reduction in variance at sub-seasonal and seasonal timescales during the 21st century under high-emission scenarios. The poor capability of CMIP6 models at simulating sub-seasonal chlorophyll dynamics casts doubt on their projections at these temporal scales and multi-annual timescales. This study underscores the need to enhance spatial resolution and constrain intrinsic biogeochemical oscillations to improve projections of ocean phytoplankton dynamics