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Passive sampling of chemical targets in Wastewater-Based Epidemiology: Promise, pitfalls and pathway forward
No full textInternational audienceWastewater-based epidemiology (WBE) is an increasingly important approach for assessing community exposure to pharmaceuticals, illicit drugs, and biomarkers, yet its reliance on autosamplers limits spatial and temporal coverage due to high cost, maintenance, and infrastructure demands. Passive sampling (PS) offers a power-free, time-integrated alternative for monitoring polar organic contaminants in complex wastewater matrices. This review examines the performance of adsorption-and diffusion-based PS devices, emphasizing how calibration, biofouling, and sorbent-analyte interactions govern quantitative reliability. In situ calibration remains essential for robust uptake estimates, while ion-exchange and mixed-mode sorbents provide enhanced selectivity and broader analyte coverage. Beyond targeted screening, PS enables semi-quantitative, non-targeted analyses through high-resolution mass spectrometry, expanding its analytical scope. Rather than replacing autosamplers, PS should be viewed as a complementary technology capable of improving spatial and temporal resolution in WBE. Ongoing innovations in design, calibration, and data interpretation will shape its integration into future wastewater surveillance frameworks
Effect of local environment on Ly line profile in DESI/ODIN LAEs
No full textInternational audienceLyman-Alpha Emitters (LAEs) are star-forming galaxies with significant Ly emission and are often used as tracers of large-scale structure at high redshift. We explore the relationship between the Ly line profile and environmental density with spectroscopy from the Dark Energy Spectroscopic Instrument (DESI) of LAEs selected with narrow-band photometry through the One-hundred-deg DECam Imaging in Narrowbands (ODIN) survey. We use LAE surface density maps in the N419 (z 2.45) and N501 (z 3.12) narrow bands to probe the relationship between local environmental density and the Ly line profile. In both narrow bands, we stack the LAE spectra in bins of environmental density and inside and outside of protocluster regions. The N501 data shows 15% higher Ly line luminosity for galaxies in protoclusters, suggesting increased star formation in these regions. However, the line luminosity is not appreciably greater in protocluster galaxies in the N419 band, suggesting a potential redshift evolution of this effect. The shape of the line profile itself does not vary with environmental density, suggesting that line shape changes are caused by local effects independent of a galaxy's environment. These data indicate a potential relationship between LAE local environmental density, ionized gas distribution, and Ly line luminosity
Critical metals behavior in amphibolite facies: metamorphic conditions and ore mineral compositions Sulitjelma and Bleikvassli Pb-Zn-Cu mines, Norwegian Caledonides.
No full textInternational audienceAs part of the Critical Metals in Orogen project (https://anr-cmio.gm.umontpellier.fr/), this study focuses on the presence and potential remobilization of critical metals, especially Indium, at the historic Sulitjelma Cu-Zn and Bleikvassli Zn-Pb-Cu mines in the Norwegian Caledonides. The style of mineralization is considered VMS and SEDEX, respectively, but both localities have suffered metamorphism and deformation during the formation of the Caledonian orogen. Ore and host rocks samples of the Sulitjelma and Bleikvassli mines were studied in order to understand the link between metamorphism, mobility, and critical metal concentrations within the mineralizations. To address this issue, several methods were used: macroscopic and microscopic analyses, thermodynamic modelling, EBSD, LA-ICP-MS, LIBS and EPMA in situ analysis. The host rocks are mostly metasediments composed of quartz, micas, garnet, staurolite, kyanite and rare sillimanite. Using pressure-temperature diagrams calculated for the host rock, we obtain for Bleikvassli, temperature conditions between 650 and 750 °C and pressure conditions between 6.5 and 11 kbar. For Sulitjelma, the metamorphic conditions are slightly lower, with temperatures between 550 and 700 °C and pressures between 5 and 12 kbar. These data suggest that the host rocks of the Bleikvassli and Sulitjelma mineralizations experienced amphibolite facies conditions associated with Barrovian metamorphism in a collisional context, in agreement with the available literature. Ore samples are dominated by pyrite–chalcopyrite–sphalerite and pyrrhotite–chalcopyrite–sphalerite assemblages, with the local presence of magnetite. EBSD results show that, in most of the samples, pyrrhotite, pyrite and chalcopyrite show a preferential orientation possibly indicating dynamic recrystallization whereas, sphalerite, appearing texturally late might have crystallized under static conditions. EMPA and LA-ICPMS in situ analytical results on the mineralizations indicate the presence of significant iron in sphalerite in both deposits with 4.4 wt% at Bleikvassli and 5.7 wt% ppm at Sulitjelma. In addition, cadmium, manganese, and indium are preferentially incorporated into sphalerite as well. In both deposits, there is a significant amount of indium in sphalerite, up to 55 ppm. Gallium and germanium concentrations in sphalerite are low. Indium and manganese are also present in chalcopyrite but at lower concentrations. By contrast, tin and silver are preferentially incorporated into chalcopyrite. Cobalt, nickel, and arsenic are enriched in pyrite
Bayesian power spectral density estimation for LISA noise based on P-splines with a parametric boost
No full textInternational audienceFlexible and efficient noise characterization is crucial for the precise estimation of gravitational wave parameters. We introduce a fast and accurate Bayesian method for estimating the power spectral density (PSD) of long, stationary time series tailored specifically for LISA data analysis. Our approach models the PSD as a geometric mean of a parametric and a nonparametric component, combining the computational efficiency of parametric models with the flexibility to capture deviations from theoretical expectations. The nonparametric component is expressed by a mixture of penalized B-splines. Adaptive, data-driven knot placement performed once during initialization eliminates computationally expensive reversible-jump Markov Chain Monte Carlo, while hierarchical roughness penalty priors prevent overfitting. This design yields stable, flexible PSD estimates with runtimes of minutes instead of hours. Validation on simulated autoregressive AR(4) data demonstrates estimator consistency. It shows that well-matched parametric components reduce the integrated absolute error compared to an uninformative baseline, requiring fewer spline knots to achieve comparable accuracy. Applied to a year of simulated LISA -channel noise, our method achieves relative integrated absolute errors of with computation times less than three minutes, which makes it suitable for iterative analysis pipelines and multi-year mission datasets
Sea Surface Wave Remote Sensing
No full textInternational audienceAs a type of gravity wave travels at the interface between atmosphere and ocean, sea surface wave is a fundamental dynamic phenomenon which must be considered in oceanographic research, offshore engineering and maritime shipping etc. With the rapid development of space science and technology, satellite remote sensing has become an indispensable technology to observe and understand sea surface waves due to its advantages of global coverage, all-weather and all-day characteristics. This chapter introduces the characterization methods and main parameters of sea surface waves, the main spaceborne microwave payloads and observation principles of sea surface waves, and the main scientific and operational applications of satellite surface wave data
Arctic seabirds exposed to acute stress display state- and environment-dependent patterns of surface temperature change, independent of mercury contamination
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Growth Rate and Energy Dissipation in Wind‐Forced Breaking Waves
No full textInternational audienceWe investigate the energy growth and dissipation of wind‐forced breaking waves at high wind speed using direct numerical simulations of the coupled air–water Navier–Stokes equations. A turbulent wind boundary layer drives the growth of a pre‐existing narrowband wave field until it breaks, transferring energy into the water column. Under sustained wind forcing, the wave field resumes growth. We separately analyze energy transfers during wave growth and breaking‐induced dissipation. Energy transfers are dominated by pressure input during growth and turbulent dissipation during breaking. Wind input during growth is balanced with dissipation during breaking over an entire growing‐breaking cycle. The wave growth rate scales with , modulated by the wave steepness due to sheltering, and the energy dissipation follows the inertial scaling with wave slope at breaking, confirming the universality of the process. Following breaking, near‐surface vertical turbulence dissipation profiles scale as , with their magnitude controlled by the breaking‐induced dissipation
Biodiversity co-variation patterns in a range of soil organism taxa across highly contrasting ecosystems
No full textInternational audienceSoil biodiversity as a critical component of terrestrial ecosystems and their functioning varies across spatial scales and environmental conditions. However, it remains unclear whether and how biodiversity patterns co-vary among different soil taxa across ecosystems.In this study, we compared diversity patterns of plants, earthworms, nematodes, bacteria, and fungi, as five major groups of soil organisms, across six strongly contrasting ecosystems ranging from mountain peatland to crop fields, including within-ecosystem variation in soil moisture. We hypothesized co-variation in taxonomic richness (alpha diversity) and composition (beta diversity) of multiple groups of soil organisms across ecosystems, moisture conditions and spatial scales.In partial contrast to our initial hypothesis, co-variation in the taxonomic richness among these groups was limited, though significant positive associations were found among bacteria, fungi, and earthworms across all sites. Plant diversity showed distinct associations with soil organism diversity, particularly with earthworms and bacteria, highlighting above-belowground biodiversity linkages. Beta diversity showed substantial co-variation among all soil organism groups, reflecting a spatial coupling of their communities that was influenced by differences in soil moisture conditions. These patterns were more pronounced in near-natural and no-till agroecosystems compared to conventional agricultural systems. Our results highlight that ecosystem type shapes broad-scale taxonomic richness, while local soil moisture critically influences soil biodiversity and spatial community composition, emphasizing the multi-scale drivers of soil biodiversity.</div
Characterizing the magnetic signal generated in the magnetosphere from 1996 to 2024 using ground geomagnetic data
No full textInternational audienceThe geomagnetic field, as observed at the Earth’s surface or LEO satellite altitudes (between 300 km and 800 km), is the combination of signals generated by various internal and external sources. The internal sources are mainly associated with the liquid outer core flow, magnetized rocks in the lithosphere and induced electric currents in the crust and mantle. External sources are electric currents flowing in the ionosphere and magnetosphere. We focus on the contributions from the magnetospheric fields and describe a modeling approach in Spherical Harmonics (SH) based on magnetic observatory vector field measurements. The aim of this study is to model the magnetospheric field contributions observed during geomagnetically quiet time up to SH degree 6, with a 1-h temporal resolution for the period covering years 1996.0–2024.8. The adopted modeling approach is based on the Kalman filter and the correlation-based technique, which leads to series of hourly snapshot models together with robust error estimates. The series of models in time compare well with the global magnetospheric Ring Current index (RC). We observed and described various magnetospheric field structures, including local time asymmetries and contributions from ring and magnetotail currents. We also examined annual, semi-annual, monthly and daily variations in magnetospheric field Gauss coefficients in the Fourier domain
A light-entrained clock mechanism in a hydrozoan jellyfish synchronizes evening gamete release
No full textInternational audienceFor marine species that reproduce by external fertilization, spawning is precisely coordinated within a local population to maximize the chances of producing offspring. Gamete release is often synchronized with respect to the diel light changes at dawn and dusk. In the hydrozoan jellyfish Clytia hemisphaerica , spawning occurs when oocyte maturation and gamete release are induced by maturation-inducing hormone (MIH) neuropeptides released from opsin-expressing cells in the gonad, directly upon light stimulus. Here, we characterize the distinct spawning cycle of a previously undescribed species Clytia sp. IZ-D, identified on the Pacific coast of Japan, which releases gametes in the evening. Clytia sp. IZ-D jellyfish spawn 14 hours after a light stimulus under a 24-hour light cycle and exhibit autonomous and synchronized spawning cycles with a 20-hour interval under constant light. We find that the female spawning cycle reflects the oocyte growth and their acquisition of competence for maturation, such that each day a new batch of growing oocytes becomes responsive to MIH at a time that correlates with the timing of actual spawning. We propose that the synchronized evening spawning in this species is controlled by an atypical circadian timing mechanism based on the progressive development of gamete competence to MIH and modulation of the opsin-controlled MIH signaling pathway. This mechanism may provide resilience to light cycle instability due to local climate variation and ensure reproductive isolation from other Clytia species by shifting the gamete release timing