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The Network for the Detection of Atmospheric Composition Change at 35 Years: Achievements and Future Strategy
No full textInternational audienceSince 1991, continuous, consistently calibrated and openly archived ground-based measurements from the Network for the Detection of Atmospheric Composition Change (NDACC) have been collected to investigate processes responsible for decadal-scale changes, anomalies in atmospheric composition, and to validate satellite observations and model simulations. These measurements, from nearly 120 stations, support fundamental research in the area of stratospheric and tropospheric processes impacting ozone chemistry, greenhouse gases, atmospheric radiative forcing, air quality, and interactions with solar radiation and the entire Earth system. NDACC data are supplemented by observations from 11 global Cooperating Networks. The operational principles of Cooperating Networks are well aligned with NDACC objectives and protocols, focusing on data that (a) are high-quality, uniformly processed and traceable to reference standards; and (b) capture short-term (daily to interannual) anomalies and long-term trends. This paper summarizes the NDACC organizational structure. We review the major accomplishments of NDACC since De Mazière et al. (2018), collaborative research with Cooperating Networks, and interactions with the satellite and modeling communities. Ground-based atmospheric composition monitoring is at a crossroads. Challenges include sustainability of human and financial resources required for complex and intensive data collection, technical issues including aging instrumentation, requirements for FAIR (findable, accessible, interoperable, reusable) data, and lack of data over most of Asia, Africa and South America. NDACC is well-positioned to adopt a three-pronged strategy going forward: protecting and modernizing existing stations; promoting the growing use of NDACC data; expanding the number of measured species and network coverage in under-sampled or under-reporting regions
Investigating post-wildfire effects in contrasted Mediterranean ecosystems
No full textInternational audiencePurpose: This review examines the effects of wildfires in Mediterranean and contrasted ecosystems (e.g. in terms of topography, vegetation cover, wildfire history) through the prism of ecosystem components. This approach considers the multiple components of the ecosystem, including soils and sediments, water, and biota, as well as external stressors such as chemical contaminants, to assess the multiple impacts of wildfires. These impacts, which spread from upper to lower catchment areas, affect all ecosystem components, physical, biological, and functional, in a cumulative process along the entire trajectory. Their extent and nature depend on both the intrinsic characteristics of the environment, such as topography, vegetation cover, soil type, and hydrological connectivity, and the characteristics of the wildfire, including its intensity, severity, extent, and frequency. By investigating erosion processes, biodiversity changes and their impacts via environmental DNA analysis, the redistribution of fire retardants, and sediment transport, the aim is to provide a comprehensive understanding of wildfire effects. The main objective of the current review is to synthesize existing knowledge and to identify critical gaps in our understanding of the interactions between these factors, including wildfire, biodiversity, erosion, and contaminants. Methods: Relevant journal articles were extracted from the Clarivate Web of Science database as of September 9, 2025. A total of 161 publications were analyzed, and their findings were categorized into three thematic axes related to wildfire effects: post-wildfire erosion and sediment dynamics, biodiversity assessment using environmental DNA (eDNA), and the transfer of contaminants such as flame retardants and Polycyclic Aromatic Hydrocarbons (PAHs). Results and Conclusion: The results highlighted the complex relationships between wildfire-induced erosion, sediment dynamics, biodiversity and the effects of contaminant transfers in impacted areas. Accordingly, the need to implement comprehensive long-term research, conducted over more than two decades and conducted at integrative spatial scales (e.g. at the catchment level), to improve our understanding of ecological connectivity, sediment transport dynamics, and the cumulative effects of wildfires is demonstrated
From Solution to Surface: How the Catalytic Environment Modulates Peptide Bond Cleavage by Metal‐Oxo Cluster Nanozymes
No full textInternational audienceABSTRACT Nanozymes that selectively cleave proteins offer a promising alternative to natural proteases due to their superior stability, tunability, and scalability. However, they are either water‐soluble, preventing efficient recovery and limiting their practical application, or structurally ill‐defined and insoluble, hindering mechanistic understanding and rational catalyst design. To address this, we developed a structurally well‐defined dodecanuclear hafnium‐based metal‐oxo cluster with a tunable solubility that enables direct comparison of homogeneous and heterogeneous catalytic behavior in peptide bond hydrolysis. The soluble cluster, Hf 12 (sol), and its insoluble counterpart, Hf 12 (precip), share identical core structures according to pair distribution function analysis and possess highly similar ligand environments as indicated by solution‐ and solid‐state NMR as well as FT‐IR spectroscopy. We demonstrate that both forms efficiently cleave peptide bonds in the dipeptide glycylglycine and the more complex protein myoglobin. Solution‐based spectroscopic studies with Hf 12 (sol) show direct coordination of the peptide bond to Hf(IV) centers, with substrate stabilization via cooperative binding to the cluster, whereas Hf 12 (precip) shows reusability over multiple reaction cycles without loss of structural integrity. This highlights the potential of group IV metal‐oxo clusters as synthetic proteases and offers a rare platform to correlate molecular reactivity with macroscopic catalytic behavior across phases, thereby deepening our understanding of how proteolytic reactions can be modulated by catalyst structure and solubility
Réflexions sur la soumission à un déséquilibre significatif entre professionnels
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Multi-analytical identification of the synthetic opioids cychlorphine and methiodone (IC-26) in drug seizures: first detection in Europe
No full textInternational audienceAbstract Objectives The rapid emergence of highly potent synthetic opioids represents a growing challenge for forensic and clinical laboratories. Methods We report the first identification in Europe of methiodone (IC-26) and the first detection in France of cychlorphine in drug samples collected by a drug-checking service in Paris. Results Preliminary screening by liquid chromatography with diode-array detection (LC-DAD) and gas chromatography coupled with mass spectrometry (GC-MS) revealed unknown peaks due to the lack of corresponding spectra in available spectral librairies. High-resolution mass spectrometry (LC-HRMS) provided accurate mass measurements consistent with the cychlorphine and Methiodone formulas. Structural confirmation was obtained by 1D/2D nuclear magnetic resonance (NMR) spectroscopy. Targeted LC-MS/MS quantified 5 % cychlorphine and 2 % methiodone, with no other psychoactive compounds detected. Conclusions These results highlight the limitations of library-based screening and the value of multi-platform strategies integrating LC-HRMS, LC-MS/MS, and NMR for the early detection of emerging drugs
Iron Metallurgy in Ancient Cambodia: Production Dynamics, Traditions and Chronologies in a Southeast Asian Context (9th–14th centuries CE)
No full textInternational audienceCollaborative studies in iron archaeometallurgy in Cambodia over the past decade, particularly through the IRANGKOR project, have advanced our understanding of iron production dynamics during the Angkorian period (9th–15th centuries CE). This research examines metallurgical remains and artifacts within a systemic framework, linking them to production sites, geological contexts, and usage settings, such as iron clamps in monumental constructions. Studied diachronically and across multiple spatial scales, these remains provide insights into production practices and “recipes,” production dynamics, and the circulation and supply of iron, particularly within the central production territory of Phnom Dek, historically recognized for its metallurgical tradition.The study explores the relationships between resources, production processes, metallurgical practices, and iron circulation. Central to the research is the use of provenance analyses, direct dating of the metal itself, and the examination of comparative patterns, providing precise chronological and spatial benchmarks. Combining historical and archaeological sources with material analysis of artifacts and smelting debris establishes a framework for interpreting these dynamics across the Angkorian territory.The resulting datasets reveal changes in metallurgical “recipes” as well as in supply strategies and demands over more than 1,400 years. This presentation synthesizes recent results, highlighting the contribution of compositional and chronological data to frameworks for understanding continuities and changes in ancient metallurgical practices. Situating these findings within a broader Asian context highlights similarities in practices and recipes and their implications for regional technical dynamics
Author Correction: Increasingly negative tropical water–interannual CO2 growth rate coupling
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Data paper: Milk production, body weight and body condition score during lactation in dairy goats: time-series data and model-based curves from two French herds
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Characterization of extracellular vesicles at parturition in dairy cows with lategestation heat stress
No full textInternational audienceThis study investigated how late-gestation heat stress (HT) affects extracellular vesicle (EV) protein profiles in dairy cows at parturition. Plasma EV were isolated from heat-stressed and cooled (CL) cows and analyzed by mass spectrometry. A total of 684 proteins were identified, of which 20 differed significantly between treatments. The EV from cooled cows were enriched in extracellular matrix and coagulation proteins, including laminins, collagen IV, fibrinogen, and von Willebrand factor. The presence of these proteins in CL cows suggests that cooling enhances molecular pathways involved in tissue repair and postpartum recovery. Conversely, immunoglobulin-related proteins and specific receptors were reduced in cooled cows, potentially reflecting lower immune stress. These findings indicate that HT during late gestation alters EV-mediated signaling related to metabolism, immune modulation, and tissue remodeling at parturition. The identified proteins may serve as potential biomarkers for assessing maternal adaptation and recovery, emphasizing the importance of environmental cooling during the dry period. NTA = nanoparticle tracking analysis; trt = treatment.Highlights• Heat stress during late gestation significantly alters EV content.• Cooling increased extracellular matrix and coagulation proteins, perhaps for tissue repair and postpartum recovery.• Cooling decreased immunoglobulin-related proteins and certain receptors in EV.• Changes in EV proteins may reflect improved recovery and lower immune stress with cooling
