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Importance of species identity, species mixing and understory on carbon and nitrogen stocks in sessile oak and Scots pine stands
No full textarticle de 17 p.International audienceForests contribute the most to the carbon stocks of the terrestrial biosphere. Estimates are available at different scales, though a large degree of uncertainty remains. In particular, the understory is seldom taken into account. In this study, we measured the carbon and nitrogen stocks of all ecosystem compartments, including trees, understory, deadwood, and soil, in pure sessile oak, pure Scots pine and mixed stands of the two species. We studied the importance of different compartment stocks and the effects of stand composition. We also evaluated different sources of uncertainty related to the calculation parameters of the estimates.We found that species identity affected ecosystem C and N stocks more than stand composition did. The effects were primarily observed in the forest floor (mainly the organic layer) and the understory. No stand composition effects were observed for either soil C stability or C and N stocks in the mineral horizons, indicating that physicochemical processes dominate. Our results show that the understory can account for more than a quarter of vegetation C stocks and up to one-half of vegetation N stocks in pine low density stands. This importance of the understory was most significant in low-density pure pine stands. The root biomass of the trees and understory vegetation were the primary sources of uncertainty in stock estimations
FRCAW literature review on the impact of partly or fully solid flooring systems on the welfare and behaviour of pigs
No full textInternational audienceBACKGROUND TO THE REQUESTCouncil Directive 2008/120/EC (European Council, 2008) prohibits routine tail-docking (partial removal of the tail) for piglets. The practice is permitted only when outbreaks of tail-biting occur on a pig farm and other measures have already been tried. Four animal protection associations (CIWF France, Welfarm, OABA, LFDA) have brought the following facts to the attention of the FRCAW:•Tail docking is still routinely practised, despite Directive 2008/120/CE. •Enrichment of their surroundings with litter and/or foraging materials is proving effective as a way to allow pigs to express their exploratory behaviours and thereby limit tail-biting.•Provision of enrichment materials for sows allows them to express their nest-building behaviour.•Fully-slatted flooring, the system most commonly used on pig farms, makes it hard to provide litter and/or foraging materials inside farm buildings.The four animal protection associations, in their capacity as members of the Advisory Committee of the FRCAW, have asked the FRCAW to answer the following question: What are the impacts of different solid flooring systems (partial/total) with or without the presence of bedding and/or foraging materials, on pig welfare and, particularly, on pig behaviours (manipulation, exploration, posture, interactions between animals, maternal behaviours, defecation behaviours) compared with a fully slatted floor ? The FRCAW’s response will consider all categories of animal and all stages of development as defined by the pig industry. The FRCAW was also asked to examine further issues, in particular, the factors enabling optimal use of fully or partly solid flooring systems and the obstacles and levers relating to their installation on pig farms. MAIN CONCLUSIONS OF THE FRCAWImpacts of alternatives to fully slatted flooring systems on the exploratory and nesting behaviours natural to pigs The alternative flooring systems to a fully slatted floor are:•partly slatted flooring (also known as partly solid flooring) •bare solid floor •solid floor, raked litter (regular addition of straw, and scraping) •solid floor, deep litter (a large quantity of litter is initially provided, to which further materials are regularly added)The systems that provide the best welfare conditions for pigs are solid floors with raked litter or deep litter. These systems improve pig welfare because they are compatible with the distribution of large quantities of litter or forage. Litter and forage materials such as unchopped straw with long stalks (stalks > 7 cm) are the most effective materials to allow pigs to express exploratory and digging behaviours and to avoid the development of undesirable behaviours directed towards other pigs such as tail biting. The supply of 20 g of straw per pig per day reduces tail biting and the positive effect increases with the quantity supplied. Pigs’ exploratory behaviours are met by the provision of 200 g/pig/day. The optimal quantity to prevent tail biting is 400 g/pig/day.For peri-partum sows, long-stemmed straw is best-suited to a sow’s nest-building needs. There is currently insufficient data to determine the optimal quantity to meet this need. Fully slatted flooring does not allow adequate provision of litter as this would be likely to obstruct the gaps between the slats and block the effluent evacuation system. Partly slatted flooring is more suited to the spreading of litter than fully slatted systems, but is not optimal. The FRCAW therefore recommends the preferred use of flooring systems that are fully compatible with the provision of long-stemmed litter and forage in large quantities, that is to say, solid flooring systems, when planning new buildings or renovating old ones. Given that fully slatted flooring remains the most common system on French pig farms, the review suggests possible ways to adapt farming practices and modify buildings designed with slatted floors to provide animals with a better experience, while awaiting the opportunity to replace flooring systems when buildings are renovated. Additional effects of solid flooring on pig welfareCompared with fully slatted systems, solid or partly-solid floors increase the animals’ sleeping comfort and their thermal comfort during periods of low temperature, allowing the animals to establish separate functional areas, as a consequence of the greater space available, and are associated with the reduction of the occurrence of lesions and wounds to the feet and lameness. The positive impacts from these welfare criteria increase incrementally (fully slatted flooring < partly slatted flooring < solid flooring < scraped litter < deep litter) in relation to the quantity of straw supplied. However, these flooring types require better management of the building atmosphere (ventilation) and a larger available surface area in order to control the cleanliness of the animals and their accommodation, their thermal comfort in hot weather and the risk of infectious diseases. Obstacles and levers for the implementation of alternatives to fully slatted flooringThe expert report includes a table summarising the obstacles and levers for the development of alternatives to fully slatted flooring, which are essentially linked to socio-economic and environmental factors. To remove the concerns of some farmers over the financial viability and technical practicalities of transition to an alternative farming system, the principal identified levers include the sharing of success stories, training, the dissemination of research and development findings, and financial support from local and national government
Gender Inequality in Managing Childhood Sleep: Which Parent Gets up at Night?
No full textInternational audienceObjective: Parental responsibilities for childcare remain unequally distributed between mothers and fathers. This study investigates whether such gender disparity also applies to night-time care, particularly when children experience sleep disorders.Methods: We conducted a cross-sectional survey study including 882 clinical files from sleep consultations for children aged 0 to 5 years, completed by one parent (98% mothers). To assess inter-rater reliability, 112 father–mother dyads outside the clinical setting were also surveyed. Additionally, 1409 mothers from the general population formed a control group.Results: In the clinical group, 60% of children were cared for exclusively by their mother at night, versus 9% by the father. In the control group, the figures were 64% and 6%, respectively. Gender disparities persisted even when both parents worked full-time or when the child was no longer breastfed. Inter-rater reliability was strong (r > 0.70). Factors such as number of night awakenings, child’s age, and maternal education influenced caregiving distribution. Greater maternal involvement was associated with increased psychological distress and lower relationship satisfaction.Conclusions: Mothers remain the primary caregivers at night, even in dual-earner families. This unequal distribution can affect maternal well-being and couple dynamics. Promoting paternal involvement may reduce maternal overload and improve child sleep outcomes
New lanthanide complexes for in vivo luminescent biphotonic and MRI imaging
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New NIR imaging agents based on the incorporation of lanthanide complexes in nanoparticles: applications for cancer cells detection
No full textInternational audienceOptical imaging in the near-infrared (NIR) range is of strong interest for biological research and medical diagnostic. In addition to deeper tissues penetration, emission in the NIR allows to improve both the detection sensitivity (absence of autofluorescence background) and the image resolution. The luminescence of lanthanide(III) cations (Ln3+) is attractive as they exhibit sharp emission bands, that are not affected by any environment changes (pH, temperature…). The key requirement to generate their signals is to sensitize them with a chromophore that absorb excitation light and transfer the resulting energy to the lanthanide(III). In this respect, metallacrowns (MCs) allows to coordinate and sensitize the lanthanide(III). Our lab has created several families of lanthanide(III)/zinc(II) and lanthanide(III)/gallium(III) MCs1,2,3,4. However, their use in biological system have been limited by their lack of solubility in water.Polystyrene nanoparticles (PS-NPs) are extensively utilized in biological and medical research due to their versatility, their biocompatibility and unique properties (monodispersity, tunable size, functionalization…). Recently, our lab has developed a methodology to encapsulate a large number of lanthanide-based complexes in functionalized PS-NPs through a rapid swelling process1, allowing us to incorporate a large number of MCs. Functionalized PS-NPs are used as a platform for vectorization with small molecules, peptides or antibodies.For this project, HER2-overexpressing breast cancer was taken as a model to develop targeted lanthanide-based NIR optical imaging agents. The first PS-NPs containing NIR-emitting MCs with specific HER2 targeting, addressed by the surface conjugation of a monoclonal antibodies, trastuzumab, were generated and characterized in vitro. These nanoparticles showed (i) the conservation of the specific binding properties to HER2 at the surface of cancer cells, (ii) unique photophysical properties from Ytterbium(III) ion and (iii) an absence of cytotoxicity. These nanoparticles show supplementary properties suggesting potential theranostic applications.These PS-NP are extremely promising as they constitute a versatile system that could be adapted to other targets, to multiplex and/or multimodal imaging modalities
Gut microbiota alterations are linked to COVID-19 severity in North African and European populations
No full textInternational audienceAlthough COVID-19 primarily affects the respiratory system, many patients experience gastrointestinal symptoms, suggesting a role for the gut microbiota in disease pathogenesis. To explore this, we performed shotgun metagenomic sequencing on stool samples from 200 COVID-19 patients and 102 healthy controls in Morocco and France. Despite geographic differences in microbiota composition, patients with COVID-19 in both continents exhibited significant gut microbiota alterations, which were more pronounced in severe cases, with similar features compared with controls. Functional pathways, including L-Tryptophan biosynthesis, were disrupted, particularly in patients with severe disease. Machine learning models accurately predicted disease severity based on gut microbial profiles in the Moroccan cohort, though not in the French cohort. These results highlight consistent microbiota changes associated with COVID-19 and support a potential link between gut dysbiosis and disease severity.The ongoing coronavirus disease 19 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been a major cause of death worldwide in the last three years (World Health Organization). Although COVID-19 is a respiratory illness, about 10-20% of patients suffer from gastrointestinal symptoms, including loss of appetite, diarrhea, nausea, and vomiting 1,2 . These symptoms are often associated with a high level of fecal calprotectin (an indicator of intestinal inflammation) and interleukin 18 (IL-18, a cytokine that mediates intestinal inflammatory reactions) in patients' stools 3,4 . COVID-19 RNA and, more rarely, infectious viruses can be detected in infected patients' fecal samples, suggesting that the gastrointestinal tract is a major target organ of SARS-CoV-2 infection 5,6 . Moreover, the Angiotensin-Converting Enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2), both critical proteins for entry of SARS-CoV-2 into host cells, are expressed at high levels in the gastrointestinal epithelial cells 7 .Increasing evidence from preclinical models and clinical studies suggests that SARS-CoV-2 infection leads to alterations of the gut microbiota and that gut dysbiosis could be involved in COVID-19 severity 8-15 . Patients experiencing severe COVID-19 have significant alterations in gut microbiota's composition, characterized by a loss of microbial diversity and richness. In several cohorts, SARS-CoV-2 infection was associated with depletion of beneficial taxa, including butyrate producers (e.g., genera from the Ruminococcaceae family) and bacterial species with known immunomodulatory potential (e.g., Faecalibacterium prausnitzii and Eubacterium rectale) 10,16-18 . In contrast, enrichment of potential opportunistic pathobionts was reported in COVID-19 patients, such as Bacteroides nordii, Rothia, Actinomyces, Ruminococcus, and Clostridium hathewayi 10,16-19 . Of interest, a limited number of studies, mostly in Asian populations, pointed out stronger microbiota alterations in patients developing severe COVID-19 15,20,21 . Beyond the taxonomy, recent studies have shown functional alterations linked to COVID-19, including metabolic pathways related to SCFA production and bile acid metabolism 12,22 . However, only European, North American, and Asian populations have been studied in this regard, and no data are available for African patients suffering from COVID-19 infection.In the current study, we compared the gut microbiota of 200 patients with COVID-19 and 102 healthy subjects from Moroccan and French cohorts. Through shotgun metagenomics and targeted quantitative metabolomics, we showed that COVID-19 infection is associated with alterations in the gut microbiota diversity, composition, and functions in both populations. Interestingly, we found common signals in the patients from the two continents. The strength of the alterations is more marked in severe COVID-19 patients. Finally, we showed that a machine learning-based approach using only bacterial taxa could predict COVID-19 infection severity with high accuracy, but it was not transposable from one population to the other.</div
Grammatical Path Network: Unveiling Cycles Through Path Computation
No full textInternational audienceGraph Neural Networks (GNNs) have demonstrated strong capabilities in learning from structured data. Yet efficiently capturing cycle-related information remains a computational challenge. In this work, we introduce a novel GNN called Grammatical Path Network (GPN) to efficiently capture cycle-related information inside graph structures. GPN leverage Context-Free Grammars (CFGs) for cycle counting through path precomputation. Inspired by the Graph Substructure Network (GSN) framework and recent advances in GNN expressiveness, GPN exploits CFG-based representations to encode cycles of length l + 1 by precomputing paths of length l at the edge level. This formulation eliminates the need for explicit cycle counting, while maintaining strong predictive performance. Our experiments on benchmark datasets demonstrate that GPN achieves comparable or superior results to GSN in tasks requiring cycle-aware representations, highlighting its efficiency and effectiveness. These findings suggest that CFG-guided path precomputation offers a scalable alternative for capturing higher-order structural dependencies in graph-based learning.</div
Veni Bibi Vichy. Current state of archaeological knowledge on ancient thermal spas in Vichy (France): thermal baths that do not always reveal their source
No full textInternational audienceThe aim of this collective paper is to present the current state of knowledge on ancient thermalism in Vichy.In the 19th and 20th centuries, the town of Vichy (Allier, Auvergne-Rhône-Alpes, France) experienced a boom linked to its spa industry, basing its reputation on the curative virtues of its hot waters, recognised since antiquity. Local scholars, usually doctors, took an interest in the archaeology, and uncovered the town’s ancient past. Through references to exceptional remains, they built up an image of an idealised spa town, identified as Aquis Calidis on the Peutinger Table, and furnished with monumental thermal baths.Research carried out since the mid-19th century on the thermal aspect of the city has produced a wealth of documentation which is often redundant and imprecise. In addition, construction work on top of the modern baths has largely altered the previous layout around the springs, restricting access to potential remains and making it difficult to carry out an archaeological study of these areas. However, it is still possible to take a fresh look at the issue: what remains and artefacts have been found? How can they be interpreted? Which uses were they destined for in association with the waters?A recent study of this archaeological data as part of university research and preventive archaeology operations has enabled us to reconsider the image of the ancient town, to clarify its topography and to gain a better understanding of how the springs were used in Roman times. A bibliography review, a study of the water catchments, the reinterpretation of artefacts (votive offerings, beakers, etc.) and new field data confirm that two hot mineral springs were tapped during antiquity (Chomel, Hôpital), and a third is thought to have been used (Lucas). They also reveal the existence of specific ancient installations in the vicinity of these springs (pools, galleries, pipes, etc.) and offer a glimpse into the curative purposes of the thermal waters.Furthermore, the recent discovery of monumental non-curative thermal baths in Cusset, less than 5km from Vichy, raises many questions about the relationship between these two places. Vichy town council, keen to highlight the ancient past of this ‘Queen of the spa towns’, wants to promote the town’s spa heritage
Dynamiques des recherches en sciences de l'information et de la communication.: Information - Communication : Défis contemporains 4ème édition révisée
No full textInternational audienceIn the digital age and media upheavals, information and communication sciences (ICS) are an essential disciplinary field to decipher the transformations of our societies. This collective work, the result of the work of the Permanent Conference of Directors of CIS research units explores the recent dynamics that drive this field in full effervescence.Over the course of its three parts: Journalism, information, media; Images, cinema, audiovisual media and cultural industries; Public and political communication, it presents the work of the units and their researchers to answer three questions, in the continuity of previous editions: what are the major themes of the work conducted by researchers in information and communication sciences? What research and publications are representative of the discipline? What are their contributions to a better knowledge of contemporary societies? A stimulating dive into the debates, practices and innovations that shape our media and political world.Book written and edited by the Permanent Conference of Directors of Research Units in Information and Communication Sciences.À l’ère du numérique et des bouleversements médiatiques, les sciences de l’information et de la communication (SIC) s’imposent comme un champ disciplinaire essentiel pour décrypter les transformations de nos sociétés. Cet ouvrage collectif, fruit des travaux de la Conférence permanente des directeurs et directrices des unités de recherche en SIC explore les dynamiques récentes qui animent ce domaine en pleine effervescence.Au fil de ses trois parties : Journalismes, informations, médias ; Images, cinéma, médias audiovisuels et industries culturelles ; Communication publique et politique, il présente les travaux des unités et de leurs chercheur·e·s pour répondre à trois questions, dans la continuité des éditions précédentes : quelles sont les thématiques majeures des travaux conduits par les chercheur·e·s en sciences de l’information et de la communication ? Quelles sont les recherches et les publications représentatives de la discipline ? Quels sont leurs apports à une meilleure connaissance des sociétés contemporaines ? Une plongée stimulante au cœur des débats, des pratiques et des innovations qui façonnent notre monde médiatique et politique.Ouvrage rédigé et édité par la Conférence permanente des directeurs·trices des unités de recherche en sciences de l’information et de la communication
Emission acoustique d’éléments pseudo-composite à base de sel piézoélectrique mesurée à l’aide de puces de type CMUT
No full textTransducteurs électroacoustiques et MEMS acoustiques; GTEA - Transducteurs et Électroacoustique: GAPSUS - Acoustique Physique, Sous-Marine et Ultra-SonoreNational audienceDernièrement, nous avons retenté la fabrication encapsulée, puis la caractérisation de transducteurs à base de sel piézoélectriques, notamment pour leur intérêt éco-circulaire (1, 2). Dans certains cas, un sel piézoélectrique comme le sel de Rochelle est un matériau quasi agro-sourcé du fait que le tartrate de potassium peut être extrait lors d’étapes de vinifications. Le cristal piézoélectrique peut ensuite être obtenu à partir de processus chimiques très simples. Ce sel est donc un excellent candidat pour obtenir un matériau piézoélectrique durable avec un très faible impact environnemental. Récemment, nous avons obtenu des performances suffisantes avec des réseaux rectangulaires en bioplastique remplis de monocristaux de sel de Rochelle pour pouvoir envisager l'émission acoustique dans l’air, voire de l'imagerie. Dans le même temps, le développement technologique continu de Transducteurs Ultrasonores Capacitifs Micro-usinés (CMUT) a permis d’obtenir des niveaux de sensibilité et une large bande en réception inégalés (3). Des données de caractérisation ont d’ailleurs été obtenues dans l’air par nous-même récemment. Des mesures vibrométriques ainsi que des mesures de temps de vol ont permis d’établir une possibilité de transmission acoustique entre sel piézoélectrique et CMUT au-delà du Mégahertz pour des distances de l’ordre de quelques millimètres voire centimètres. A noter qu’à plus basse fréquence dans le domaine audible, l’émission acoustiques produite par nos échantillons pseudo-composites est parfaitement audible par l’oreille humaine sur quelques centimètres. Nous pensons que ces développements pourraient à l’avenir favoriser entre autre l’émergence de systèmes ultrasonique passifs ou encore de patch acoustiques 100% biodégradables. (1) Lemaire, et al. Sensors and Actuators A: Physical 318 (2021): https://doi.org/10.1016/j.sna.2020.112483 (2) Lemaire, et al., IEEE Open Journal of Ultrasonics, Ferroelectrics, and Frequency Control (2024). https://doi.org/10.1109/OJUFFC.2024.3475348 (3) Shanmugam, P., et al., Ultrasonics 114 (2021): https://doi.org/10.1016/j.ultras.2021.10641