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Prioritising research on endocrine disruption in the marine environment: a global perspective
No full textInternational audienceA healthy ocean is a crucial life support system that regulates the global climate, is a source of oxygen and supports major economic activities. A vast and understudied biodiversity from micro‐ to macro‐organisms is integral to ocean health. However, the impact of pollutants that reach the ocean daily is understudied for marine taxa, which are also absent or poorly represented in regulatory test guidelines for chemical hazard assessment. Inspired by the United Nations Decade of Ocean Science, which aims to reverse the decline in ocean health, this communication calls for global coordination in building resources for studying the effects of marine pollution. The bibliographic analysis, a collective product of scientists from diverse backgrounds, focused on endocrine‐disrupting chemicals (EDCs). In this review, we ( i ) critically analyse the literature on endocrine signalling pathways and high‐level physiological impacts of EDCs across 20 representative marine taxa; ( ii ) identify knowledge and regulatory gaps; ( iii ) apply bioinformatics approaches to marine species genomic resources, with relevance for predictions of susceptibility; and ( iv ) provide recommendations of priority actions for different stakeholders. We reveal that the scientific literature on EDCs is biased towards terrestrial and/or freshwater organisms, is limited to a handful of animal taxa, and marine organisms are dramatically underrepresented. Our bibliographic analysis also confirmed that only a small number of (neuro) endocrine pathways are covered for all animals, whilst basic knowledge on endocrine systems/endocrine disruption for most marine invertebrate phyla is minimal. Despite significant gaps in genomic resources for marine animals, endocrine‐related protein conservation was evident across more than 500 species from diverse marine taxa, highlighting that they are at risk from EDCs. Despite recent technological advances, translation of existing knowledge into international regulatory test guidelines for chemical hazard assessment and monitoring programs is limited. Furthermore, the current understanding is confounded in part by transposing vertebrate endocrinology onto non‐vertebrate taxa. In this context, specific recommendations are provided for all stakeholders, including academia (e.g. to expand knowledge across metazoan taxa and endocrine targets and translate it to New Approach Methodologies and Adverse Outcome Pathways; to increase and improve tools for comparative species‐sensitivity distributions and cross‐species extrapolations), regulators (e.g. increase awareness of specific risks for the marine environment, prioritise international standardisation of testing methods for marine species and request evidence for absence of endocrine disruption in marine phyla), policy makers (e.g. implement sustained, long‐term international marine monitoring programs and increase global co‐operation) and the public or non‐governmental organisations (e.g. foster public engagement and behaviours that prevent marine chemical pollution; promote citizen science activities; and drive political actions towards protective and restorative marine policies). We hope that this and past reviews can contribute towards meeting ambitious international plans for marine water quality assurance, mitigation of marine pollution impacts and protection of marine biodiversity. The importance of marine biodiversity for climate change mitigation, food security and sustainable ecosystem services calls for urgent, cooperative action
Reaction Intermediates and Oxygen Ordering Explored by In Situ Neutron Powder Diffraction during Thermal Oxidation of La<sub>2</sub>CoO<sub>4.00</sub>
No full textInternational audienceThe thermal oxidation of stoichiometric La2CoO4.00 was investigated using in situ neutron and X-ray powder diffraction in air, complemented by thermogravimetric analysis (TGA). The process involves the topotactic insertion of extra oxygen atoms into interstitial lattice sites, forming La2CoO4+δ. Oxygen uptake initiates above 320 K, leading to a sequence of phase transitions as a function of temperature (T) and oxygen excess (δ). The structural evolution starts from an orthorhombic phase at δ = 0, transitions to a tetragonal phase for 0.05 ≤ δ ≤ 0.17, and proceeds through two distinct orthorhombic phases, both exhibiting long-range oxygen ordering above 525 K. The maximum oxygen concentration, observed above 680 K, corresponds to La2CoO4.263. The resulting phase diagram reveals rapid oxygen diffusion and ordering kinetics, accompanied by subtle structural modifications as a function of δ. Notably, the long-range oxygen order remains stable over a wide temperature range. Each phase was structurally characterized using Rietveld refinement
The influence of the organic residue and the solvent in the Schlenk equilibrium for Grignard reagents in THF. A molecular dynamics study with machine learning potentials
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In situ saxs investigation of the formation of mesostructured materials structured from polyion complex micelles
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Access to agricultural lands influences the effects of seasonal drought on early growth and juvenile body mass in a large herbivore
No full textInternational audienceIncreasing rainfall deficits threaten the persistence of terrestrial large herbivores, yet, very few studies have investigated the effects of droughts on populations inhabiting anthropized areas, which dominate European landscapes. We investigated how rainfall deficits (measured using the Standardized Precipitation Index, SPI) and local agricultural land use shaped the early growth of fawns and the body mass that they attained by their first winter in a population of European roe deer (Capreolus capreolus) in southwestern France. Using data on 155 new-born fawns, we found that early growth decreased as local woodland availability increased, irrespective of spring rainfall conditions. In contrast, based on data from 218 GPS-monitored juveniles, aged 8-10 months, we found that local landscape composition and seasonal rainfall deficits had interacting effects on winter body mass. The juveniles were generally heavier with higher proportions of meadows in their predicted home range (mean 0.4 kg +/- 0.2 SE), but this difference disappeared following dry summers (SPI < 1). Juveniles with low access to summer crops (e.g., 5%) were significantly lighter following dry autumns (mean -0.9 kg +/- 0.3 SE), whereas this was not the case for those with higher access to these crops (e.g., 20%). Although populations of large herbivores may respond to harsh climatic conditions by exploiting anthropogenic resources, our results suggest that any compensation effects are strongly dependent on the type of anthropogenic land use and the timing of rainfall deficits, calling for explicitly considering how local climatic conditions and human practices may interact in shaping individual performance and, so, population dynamics
Efficient Edge AI Learning with Equilibrium Propagation: A Practical Solution For Gradient Computation
No full textInternational audienceThe rapid growth of smart devices and sensors has led to an overwhelming increase in data generation, pushing current network infrastructure to its limits and threatening the scalability of cloud-based processing. Edge machine learning, which processes data locally on devices, presents a viable solution to reduce network load and latency. However, deploying deep learning at the edge remains difficult due to the limited memory and computational capacity of these devices which mostly precludes on-device/on-site training. Equilibrium propagation (EP) has emerged as a promising alternative to backpropagation, leveraging analog processing and device physics for energyefficient learning. Yet, its practical implementation is hindered by challenges such as voltage variations and the need for energyefficient circuits capable of gradient computation at a sufficient level of accuracy. Existing solutions rely on impractical idealized models. In this work, we introduce a novel method to address the problem of the wide dynamic range of the voltage variation to avoid the use of expensive low-noise amplifiers, and propose an innovative transistor-level switched-capacitor circuit to compute gradients in accordance with the EP rule. Additionally, our design supports batching, a key requirement for stable training that is often overlooked. We validate our approach on the MNIST dataset, demonstrating a practical, energy-efficient EP circuit that operates within real hardware constraints
Sensitivity of thermal evapotranspiration models to surface and atmospheric drivers across ecosystems and aridity
No full textInternational audienceEvapotranspiration (ET) lies at the core of the energy-water-carbon coupling, particularly under changing climate conditions. Yet, the sensitivity of ET models to key environmental drivers remains insufficiently understood, especially in understanding how thermal-based ET models respond to distinct influences of soil and atmospheric water stress across ecosystems. In this study, we examine the sensitivity of ET to key environmental drivers, including land surface temperature (LST), air temperature (TA), vapor pressure deficit (VPD), downward solar radiation (DSR), and fractional vegetation cover (FVC), using three representative thermal remote sensing (RS) models (STIC, TSEB, and SPARSE) together with global eddy covariance measurements.At the global scale, variance-based sensitivity analysis (Sobol' method) reveals a transition in the dominant driver of ET sensitivity from water-limited to energy-limited regimes: soil dryness (indicated by LST − TA) dominates ET variability up to an aridity index (ratio of precipitation to reference ET) of 0.54 (± 0.06), beyond which DSR becomes the primary driver. Seasonal variability and ET partitioning emphasize the critical role of soil dryness in driving soil evaporation variability, particularly during growing seasons. Furthermore, a water stress test is conducted across four representative sites with varying vegetation cover types. Results show that ET sensitivity to soil dryness nearly doubles during the drought period compared to climatological norms at the grassland site. In contrast, transpiration in forests is more strongly influenced by VPD under moderate drought stress. Analysis indicates that soil dryness generally exerts stronger control on ET than VPD. However, when vegetation cover exceeds 0.49, the influence of VPD anomalies on ET becomes comparable to soil dryness stress.This research advances our understanding of ET dynamics under increasing drought frequency and intensity. It highlights the potential of forthcoming high-resolution thermal-based RS ET products for early drought hazard warnings, climate-resilient decision-making, and sustainable agricultural water management
Evidence for the absence of a relationship between inflammation and cognition in a cohort of 1565 individuals with bipolar spectrum disorders: a Bayesian analysis of network
No full textInternational audiencePrevious studies have reported variable associations between peripheral inflammatory markers and cognitive functioning in individuals with bipolar spectrum disorders (BSD), with some identifying significant links and others finding no relationship. Such inconsistencies raise important questions about the role of inflammation in cognitive impairment among individuals with BSD. This study aims to investigate the relationship between peripheral inflammatory markers and cognitive function in a clinical sample of individuals with BSD using a Bayesian network analysis framework. We analyzed data from a large cohort (n = 1565) focusing on hsCRP and a subsample (n = 249) that included concurrent assessments of additional cytokines including Interleukin-6 and Tumor Necrosis Factor-alpha. A Bayesian approach was utilized to quantify uncertainty regarding the presence or absence of associations between inflammation and cognitive function. Our findings revealed no significant associations between inflammatory markers and cognitive performance in both samples. Strong evidence was found supporting the absence of association, with network analysis indicating distinct clusters for cognitive and inflammatory variables, suggesting they function as independent constructs with limited interactions. In our clinical sample of individuals with BSD, our findings do not support a direct association between some inflammatory markers and cognition, aligning with studies that found minimal or no associations. Our study emphasizes the importance of utilizing Bayesian methods to assess these relationships rigorously and suggests further exploration of individual differences and subgroup effects in future research
Ecological and management drivers of pest regulation via multitrophic pathways in tropical insular agroecosystems
No full textInternational audienceHighlights: • In La Réunion agroecosystems, field vegetation diversity boosts arthropod diversity. • Crop pests and damage decrease with increasing natural enemy diversity. • Pest regulation service benefits from field non-crop vegetation diversity. • Management and landscape factors also affect trophic cascades. • Vegetation diversity effects can outweigh management and landscape factors.Abstract: Natural pest regulation services provided by arthropod natural enemies are a cornerstone of ecological intensification. While vegetation diversification is known to support natural enemy communities, its relative contribution and interactions with other drivers for pest regulation services remains unclear, especially in dynamic and diversified smallholder agroecosystems under the tropics. In this study, we investigate how crop and non-crop field vegetation diversity, farming practices, climatic and landscape parameters jointly shape arthropod community structure and their services in the aerial and ground strata in tropical market gardening systems on La Réunion Island. We surveyed 22 open-field market gardening systems during two seasons. Using a multitrophic, piecewise structural equation modeling approach, we assessed direct and indirect cascading effects of local and landscape factors on arthropod diversity and pest regulation services. Results show that in aerial communities, non-crop vegetation richness generated a positive bottom-up trophic cascade. It enhanced herbivore diversity which, in turn, increased natural enemy richness, ultimately reducing pest abundance and crop damage, particularly during the dry season. In contrast, insecticide use suppressed natural enemy richness and reduced the effectiveness of pest regulation. Ground-dwelling communities were more strongly influenced by landscape fragmentation, semi-natural habitat cover, and temperature, with less evidence for structured trophic cascades. Overall, beneficial cascading effects of vegetation on pest regulation services in above-ground communities may outweigh the impacts of other management and landscape drivers. These findings underscore the potential of promoting vegetation diversity and reducing pesticide use as key strategies for enhancing natural pest regulation in tropical smallholder agroecosystems
Spatial externalities in renewable resource management: Experimental evidence on fragmented property rights
No full textWe study how spatial connectivity and fragmented ownership affect the management of mobile common-pool resources. We develop a dynamic two-patch model of a mobile renewable resource: it predicts that (i) management efficiency in a given patch declines when the neighboring patch is managed by multiple agents rather than a single owner, and (ii) greater resource mobility amplifies inefficiencies at the global scale, especially under mixed ownership. We test these predictions in a preregistered laboratory experiment with 294 participants by varying mobility rates and ownership structures. Consistent with theory, shared management in one patch reduces efficiency at the local scale (in the adjacent patch) through spillover effects, and higher resource mobility further erodes efficiency at the global scale. Using group extraction trajectories, we identify three robust behavioral patterns: early over-extractors, mid-period preemptive groups, and late preservers. Mixed ownership and higher mobility shift the distribution toward early over-extraction and away from late conservation. Beyond these institutional and ecological effects, cognitive ability is strongly associated with more forward-looking extraction paths and higher payoffs