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Gold nanoparticles–polyoxometalates composites: a comprehensive overview from synthesis and characterization to applications
No full textInternational audienceGold nanoparticles (AuNPs) have attracted attention for their unique electronic and optical properties and their wide range of applications. The development of hybrid nanoparticles by combining AuNPs with other molecules or materials is a powerful way of introducing new functions and extending their use. In particular, gold nanoparticles can be associated to organometallic complexes, biological molecules, coordination polymers or polyoxometalates (POMs), the latter being a group of soluble anionic metal oxides composed of transition metals in high oxidation states. Inorganic POMs come in a wide variety of shapes and sizes and are valued especially for their biological and catalytic properties. They are particularly interesting for the synthesis of AuNPs composites, as they can stabilize nanoparticles through electrostatic or covalent interactions and steric effects without the presence of additional surfactants, reduce gold cations by photochemical, electrochemical, or chemical reduction, or directly when used in their reduced form, and confer properties to the resulting systems. POMs can also be covalently combined with organic molecules of interest, which can in turn contribute to the functionalities of the gold nanoparticles. This review focuses on gold nanoparticles directly coated with POMs and covers their synthesis and characterization. Particular attention is also paid to their applications, including (photo)(electro)catalysis, biomedical applications (antibacterial, anticancer and anti-Alzheimer's) and their use as sensors
Experimental protocol for phase 1 of the APARC QUOCA (QUasibiennial oscillation and Ozone Chemistry interactions in the Atmosphere) working group
No full textInternational audienceThe quasi-biennial oscillation (QBO) is the main mode of variability in the tropical stratosphere, influencing the predictability of other regions in the atmosphere through its teleconnections to the stratospheric polar vortices and coupling to surface tropical and extratropical variability. However, climate and forecasting models consistently underestimate QBO amplitudes in the lower stratosphere, likely contributing to their failure to simulate these teleconnections. One underexplored contributor to model biases is missing representation of ozone-radiative feedbacks, which enhance temperature variability in the lower stratosphere, particularly at periods at and greater than the QBO (>28 months). While previous studies suggest that ozone-radiative feedbacks can impact QBO periods, amplitudes and the associated secondary circulation in the lower stratosphere, the reported impacts differ widely among models and are hard to interpret due to differences in methodology. To this end, here we propose a coordinated experimental protocol – held joint between the Atmospheric Processes and their Role in Climate (APARC) Quasi-Biennial Oscillation Initiative (QBOi) and Chemistry Climate Modeling Initiative (CCMI) activities – which is aimed at assessing the coupling between stratospheric ozone, temperature and the circulation. We use the proposed experiments to define the ozone feedback on the QBO in both present-day and idealized (abrupt quadrupling of carbon dioxide) climates. While primary focus is on the QBO, the proposed protocol also enables analysis of other aspects of ozone-radiative-dynamical coupling in the atmosphere, including impacts on the Brewer-Dobson Circulation and tropospheric eddy-driven jet responses to future climate change. Here we document the scientific rationale and design of the QUOCA Phase 1 experiments, summarize the data request, and give a brief overview of participating models. Preliminary results using the NASA Goddard Institute for Space Studies E2-2 climate model are used to illustrate sensitivities to certain methodological choices
Early mechanical reperfusion in high-risk pulmonary embolism supported by V-A ECMO: a multicenter international cohort study
No full textInternational audienceAbstract Objectives To explore how early mechanical reperfusion impacts outcomes in high-risk pulmonary embolism (PE) patients supported by veno-arterial extracorporeal membrane oxygenation (V-A ECMO). Methods This retrospective international study included adult patients treated with V-A ECMO for high-risk PE at 39 ECMO centers (2014–2024). Early mechanical reperfusion was defined as catheter-directed therapy or surgical embolectomy within 48 hours of ECMO initiation. Patients dying within 12 hours or receiving delayed reperfusion were excluded. The primary outcome was 90-day mortality, assessed using propensity-matched groups. Measurements and Main Results Among 492 patients on V-A ECMO (median age 53), 69% had cardiac arrest, and 28% received early mechanical reperfusion. After propensity matching, 137 patients were compared in each group. Ninety-day mortality was 32% with early mechanical reperfusion on ECMO versus 39% with ECMO stand-alone (HR 0.68; 95% CI, 0.45–1.03; p = 0.07). Overall, ECMO duration and weaning rates were similar; however, early mechanical reperfusion improved ECMO weaning in patients without prior thrombolysis (sHR 1.56; 95% CI, 1.03–2.36; p = 0.04). Bleeding occurred in 50% of patients, with no significant difference between groups. Conclusion In this large international cohort of patients with high-risk PE on V-A ECMO, early mechanical reperfusion therapy was not associated with a reduction in 90-day mortality or ECMO duration. These findings may support a stepwise, individualized approach favoring initial ECMO stand-alone support, although a certain clinical benefit from early mechanical reperfusion in selected patients cannot be excluded
QP-Based Control of an Underactuated Aerial Manipulator under Constraints
No full textThis paper presents a constraint-aware control framework for underactuated aerial manipulators, enabling accurate end-effector trajectory tracking while explicitly accounting for safety and feasibility constraints. The control problem is formulated as a quadratic program that computes dynamically consistent generalized accelerations subject to underactuation, actuator bounds, and system constraints. To enhance robustness against disturbances, modeling uncertainties, and steady-state errors, a passivity-based integral action is incorporated at the torque level without compromising feasibility. The effectiveness of the proposed approach is demonstrated through high-fidelity physics-based simulations, which include parameter perturbations, viscous joint friction, and realistic sensing and state-estimation effects. This demonstrates accurate tracking, smooth control inputs, and reliable constraint satisfaction under realistic operating conditions
Bridging Language Phenotypes, Neural Dynamics and Gene Regulation in Autism
No full textAutism Spectrum Disorders (ASDs) affect approximately 1% of the global population, with prevalence rising over recent decades. While ASDs are strongly heritable (~70%), translating genetic findings into effective therapeutics remains challenging due to the vast number of implicated risk genes (>700) and their limited influence in disease expression. Current interventions remain symptom-focused and do not explicitly address underlying neurodevelopmental mechanisms. Emerging approaches in functional genomics offer new insights into ASD pathogenesis by exploring the diversity of gene expression, yet clinical applications remain distant. Language deficits are among the most frequent and disabling features of ASD, profoundly affecting the individual's and family's quality of life. Recent evidence from neuroimaging and electrophysiology studies suggest that disrupted and atypical neural oscillationsrhythmic brain activity patterns -dynamics are linked to language deficits in ASD.Importantly, several ASD-associated genes modulate brain oscillatory dynamics, pointing to a potential mechanistic link between genetic variation, altered brain rhythms, and language impairment. In this perspective article, we propose an imaging genetics framework that leverages neural oscillatory profiles as both endophenotypes relevant for targeted treatment and functional readouts of gene expression. Specifically, we advocate the use of neuromodulation to target and treat altered oscillatory dynamics underlying speech communication deficits in ASD, and the integration of oscillation-related ASD candidate genes into a new, symptom-oriented model of functional genomics. This approach illustrates how bridging genetic variation, non-invasive neuroimaging, and behavioral phenotypes can advance our understanding of ASD and inform the development of targeted, mechanism-based interventions.</p
Long-term exposure to particulate air pollution and components in relation to breast cancer risk: A nested case-control study in the E3N-Generations cohort
No full textInternational audienceBackground: Previous studies on the association between airborne particulate matter(PM), particularly PM₂.₅ and PM₁₀, and breast cancer have shown inconsistent results,potentially due to variations in particle composition. To address this, we investigatedthe relationship between breast cancer and exposure to individual PM2.5 and PM10components, as well as their combined effects, in the French E3N-Generation.Methods: We conducted a nested case-control study within the cohort (1990–2011),including 5,222 incident breast cancer cases matched to 5,222 controls. Annual meanconcentrations (μg/m³) of pollutants at residential addresses were estimated usingthe CHIMERE chemistry-transport model from 1990 to the index date. Exposureassessment included nine PM components: ammonium, sulfates, black carbon,polychlorobiphenyl-153 (PCB153), nitrates, benzo[a]pyrene, cadmium, dioxins, andSaharan dust. We evaluated single-pollutant effects using simple and logisticregression, and mixture effects using Quantile G-computation (QGC) and BayesianKernel Machine Regression (BKMR).Results: Significant positive associations with breast cancer (Odds Ratios andconfidence intervals for one SD increase (controls distribution) were found forammonium (OR=1.19; 95%CI:1.05–1.35, sulfate (OR=1.17; 95%CI:1.02–1.34), PCB153(OR=1.16; 95%CI:1.08–1.26), nitrate (OR=1.15; 95%CI:1.01–1.32,black carbon(OR=1.12; 95%CI:1.05–1.19), cadmium (OR=1.05; 95%CI:1.00–1.11). QGC showed apositive association with breast cancer for a one-quartile increase in joint exposure(OR=1.22; 95% CI:1.00–1.50) with cadmium and nitrate as major contributors. BKMRconfirmed a significant positive association between the mixture and breast cancer.Conclusion: The consistency between single-pollutant and mixture analyses supportsa role for multiple PM components acting jointly on breast cancer risk. These resultssuggest that the chemical composition of PM, rather than individual pollutants alone,is a key determinant of breast cancer risk, highlighting the importance of consideringpollutant composition in air pollution research
Synchronous Miocene radiations and geographic-dependent diversification of pantropical Xylopia (Annonaceae).
No full textInternational audienc
Transcriptomic profiling reveals similarities between equine IVF and ICSI embryos
No full textInternational audienceIn vitro production of equine embryos has been performed using intracytoplasmic sperm injection (ICSI) for the last two decades. Since 2022, a repeatable protocol for conventional in vitro fertilization (IVF) provides a successful alternative. However, little is known about the influence of the fertilization method on embryo quality and the transcriptomic profile. In this study, we aimed to examine differentially expressed genes (DEGs) between ICSI and IVF embryos in the horse. Therefore, ten equine sibling blastocysts, produced in vitro by either ICSI or IVF from three different mares, were subjected to Full-Length Single-Cell RNA-Sequencing (FLASH-sequencing). As such, 11,518 genes were identified, with no DEGs between ICSI and IVF embryos. Cleavage rates, calculated on collected COCs, of IVF zygotes (55.0 %) were similar to those of ICSI zygotes (51.9 %; P = 0.74), but blastocyst rates were higher following ICSI (37.0 % vs 22.5 % calculated on collected COCs and 71.4 % vs 40.9 % calculated on cleaved zygotes; P = 0.04 and 0.004, respectively). The average day of blastocyst development did not differ (P = 0.55). In conclusion, gene expression was similar for the two fertilization techniques, supporting the safety of equine IVF for further clinical studies. Overall, the horse provides a valuable model to study longterm effects of assisted reproductive technologies with potential extrapolation to human medicine
Simultaneous estimation of radiance and its sensitivities to radiative properties in a spherical-heterogeneous atmospheric radiative transfer model by Monte Carlo method: Application to Titan
No full textInternational audienceWe propose a control variates technique to reduce the variance of null-collision Monte Carlo algorithms used for solving the Radiative Transfer Equation (RTE) in highly heterogeneous media. The method complements the classical spatially partitioned overestimate approach by additionally recording the minimum absorption coefficient within each voxel during preprocessing. During path tracing, the attenuation due to this minimum absorption is evaluated analytically, while the residual part is handled by path-samplings. This analytical treatment significantly improves convergence particularly in strongly absorbing media such as the planetary atmospheres in infrared absorbing band. The mathematical equivalence between the original and control-variates estimators is demonstrated, and numerical applications for Earth's and Titan's atmospheres confirm the expected variance reduction.</div
An inter-comparison of inverse models for estimating European CH <sub>4</sub> emissions
No full textInternational audienceAbstract. Atmospheric inversions are widely used to evaluate and improve inventories of methane (CH4) emissions across scales from global to local, combining observations with atmospheric transport models. This study uses the dense network of in situ stations of the Integrated Carbon Observation System (ICOS) to explore how well in situ data can constrain European CH4 emissions. Following the concept of inter-comparison studies of the atmospheric tracer transport model inter-comparison Project (TransCom), a CH4 inverse inter-comparison modeling study has been performed, focusing on Europe for the period 2006–2018. The aim is to investigate the capability of inverse models to deliver consistent flux estimates at the national scale and evaluate trends in emission inventories, using a detailed dataset of CH4 emissions described and presented here for first time. Study participants were asked to perform inverse modelling computations using a common database of a priori CH4 emissions and in-situ observations as specified in a protocol. The participants submitted their best estimates of CH4 emissions for the 27 European Union (EU-27) member states, the United Kingdom (UK), Switzerland, and Norway. Results were collected from 9 different inverse modelling systems, using 7 different global and regional transport models. The range of outcomes allows us to assess posterior emission uncertainty, accounting for transport model uncertainty and inversion design decisions, including a priori emission and model-data mismatch uncertainty. This paper presents inversion results covering 15 years, that are used to investigate the seasonality and trends of CH4 emissions. The different inversion systems show a range of a posteriori emission adjustments, pointing to factors that should receive further attention in the design of inversions such as optimising background mole fractions. Most inverse models increase the seasonal cycle amplitude, by up to 400 Gg month−1, with the largest adjustments to the a priori emissions in Western and Eastern Europe. This might be due to underestimation of emissions from wetlands during summer or the importance of seasonality in other microbial sources, such as landfills and waste water treatment plants. In Northern Europe, absolute flux adjustments are comparatively small, which could imply that the emission magnitude is relatively well captured by the a priori, though the lower station density could contribute also. Across Europe, the inverse models yield a similar decreasing trend in CH4 emissions compared to the a priori emissions (−12.3 % instead of −9.1 %) from 2006 to 2018. While both the a priori and the a posteriori trend for the EU-27 are statistically significant from zero, their difference is not. On a subregional scale, the differences between a posteriori and a priori trends are more statistically significant over regions with more in-situ measurement sites, such as over Western and Southern Europe. Uncertainties in the a priori anthropogenic emissions, such as in the agriculture sector (cows, manure), or waste sector (microbial CH4 emissions), but also in the a priori natural emissions, e.g. wetlands, might be responsible for the discrepancies between the a priori and a posteriori emission shift in the trends in Western, Eastern and Southern Europe. Our results highlight the importance of improving the inversion setup, such as the treatment of lateral boundary conditions and the model representation of measurement sites, to narrow the uncertainty ranges further. The referenced dataset related to the analysis and figures are available at the ICOS portal: https://doi.org/10.18160/KZ63-2NDJ (Ioannidis et al., 2025)