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Rendre compte des compétences RSE des administrateurs pour se légitimer : la gestion des impressions dans le conseil d’administration de deux banques françaises cotées.
No full textInternational audienceDans un cadre normatif fondé sur la soft law en matière de gouvernance RSE, et en l’absence de critères précis encadrant le reporting des compétences RSE des administrateurs de sociétés cotées, cet article examine comment deux banques françaises cotées cherchent à se légitimer auprès de leurs parties prenantes externes en rendant compte de la composition de leur conseil d’administration en termes de compétences RSE, afin de construire une image positive de la capacité du conseil à se saisir des enjeux de durabilité. L’étude qualitative longitudinale met en évidence que la divulgation des compétences RSE des administrateurs, d’une part, constitue un levier de gestion des impressions des parties prenantes externes donnant lieu à trois niveaux de légitimité symbolique ; d’autre part, conduit à deux types de stratégies de renforcement de la légitimité
Strain phylogroup and environmental constraints shape Escherichia coli dynamics and diversity over a 20-year human gut time series
No full textInternational audienceEscherichia coli is an increasingly antibiotic-resistant opportunistic pathogen. Few data are available on its ecological and evolutionary dynamics in its primary commensal niche, the vertebrate gut. Using Illumina and/or Nanopore technologies, we sequenced whole genomes of 210 E. coli isolates from 22 stools sampled during a 20-year period from a healthy man (ED) living in Paris, France. All phylogroups, except C, were represented, with a predominance of B2 (34.3%), followed by A and F (19% each) phylogroups. Thirty-five clones were identified based on their haplogroup and pairwise genomic single nucleotide polymorphism distance and classified in three phenotypes according to their abundance and residence time: 25 sub-dominant/transient (52 isolates), five dominant/transient (48 isolates) and five dominant/resident (110 isolates). Four over five dominant/resident clones belonged to B2 and closely related F phylogroups, whereas sub-dominant/transient clones belonged mainly to B1, A and D phylogroups. The long residence times of B2 clones seemed to be counterbalanced by lower colonization abilities. Clones with larger within-host frequency persisted for longer. By comparing ED strain genomes to a collection of commensal E. coli genomes from 359 French individuals, we identified ED-specific genomic properties including an enrichment in genes involved in a metabolic pathway (mhp cluster) and the presence of a very rare antiviral defense island. The E. coli colonization within the gut microbiota was shaped by both the intrinsic properties of the strain lineages, in particular longer residence of phylogroup B2, and the environmental constraints such as diet or phages
Diagnosing and Managing Stevens–Johnson Syndrome and Toxic Epidermal Necrolysis in Adults: Review of Evidence 2017–2023
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Lebrikizumab vs Other Systemic Monotherapies for Moderate-to-Severe Atopic Dermatitis: Network Meta-analysis of Efficacy
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Human cortical bone intrinsic permeability distribution based on 3D canalicular morphology
No full textInternational audienceBone permeability is a key parameter that drives osteocyte-based mechanobiological modelling and remodelling. While previous experimental and numerical studies have estimated bone permeability based on the morphology of the lacuno-canalicular network, these studies often relied on simplified geometries. In the current study, bone permeability was characterized using more realistic canalicular geometry for the morphological data. Bone samples harvested from 27 human femoral bones were investigated using synchrotron radiation-based nanocomputed tomography with a voxel size of 100 nm. After segmenting the canaliculi and lacunae, each canaliculus was investigated individually by applying a distance map and watershed algorithms. Bone permeability based on canalicular morphology was then assessed using the Kozeny relation, which defines the permeability of a porous medium with capillary-like pores. An averaged intrinsic permeability value of 8.8 10 -18 m 2 was obtained. It should be noted that this study considered an empty canalicular network, however in vivo, both cellular and pericellular matrices decrease space for interstitial fluid flow and thus permeability. Furthermore, a voxel size of 100 nm does not allow for the detection of smaller canaliculi, which may also modify average permeability. With the current data set and the analytic process applied, the results showed a heterogeneous permeability distribution within bone tissue, both when comparing osteonal and interstitial tissues and within an individual osteon. A difference was observed between male and female samples, and permeability appeared to significantly decrease with age. Finally, a significant correlation was found between permeability and canalicular length density, defined as canalicular length per unit bone volume. This study proposes a new form of the Kozeny law to express bone canalicular permeability as a proportional relationship with the canalicular length density. Importantly, this parameter can be directly quantified through confocal fluorescence microcopy, which is more convenient than synchrotron radiation-based nano-computed tomography. In conclusion, the current study confirms that confocal microscopy can be serve as a reliable tool to estimate bone permeability. However, the permeability values calculated here are solely based on canalicular morphology and do not consider cellular and peri-cellular intra-canalicular features
Solar radiation estimation in West Africa: impact of dust conditions during 2021 dry season
No full textInternational audienceThe anticipated increase in solar energy production in West Africa requires high-quality solar radiation estimates, which is affected by meteorological conditions and in particular the presence of desert dust aerosols. This study examines the impact of incorporating desert dust into solar radiation and surface temperature estimations. The research focuses on a case study of a dust event in March 2021, which is characteristic of the dry season in West Africa. Significant desert aerosol emissions at the Bodélé depression are associated with a Harmattan flow that transports the plume westwards. Simulations of this dust event were conducted using the WRF meteorological model alone, as well as coupled with the CHIMERE chemistry-transport model, using three different datasets for the dust aerosol initial and boundary conditions (CAMS, GOCART, MERRA2). Results show that considering desert dust reduces estimation errors in global horizontal irradiance (GHI) by about 75%. The dust plume caused an average 18% reduction in surface solar radiation during the event. Additionally, the simulations indicated a positive bias in aerosol optical depth (AOD) and PM10 surface concentrations. The choice of dataset for initial and boundary conditions minimally influenced GHI, surface temperature, and AOD estimates, whereas PM10 concentrations and aerosol size distribution were significantly affected. This study underscores the importance of incorporating dust aerosols into solar forecasting for better accuracy. Short summary Solar energy production in West Africa is set to rise, needing accurate solar radiation estimates, which is affected by desert dust. This work analyses a March 2021 dust event using a modelling strategy incorporating desert dust. Results show that considering desert dust cut errors in solar radiation estimates by 75% and reduces surface solar radiation by 18%. This highlights the importance of incorporating dust aerosols into solar forecasting for better accuracy
Biharmonic Hypersurfaces in Euclidean Spaces
No full textAn isometric immersion is biharmonic if , i.e. if , where and are the metric Laplacian and the mean curvature vector field of respectively. More generally, biconservative hypersurfaces (BCH) are isometric immersions for which only the tangential part of the biharmonic equation vanishes. We study and construct BCH that are holonomic, i.e. for which the principal curvature directions define an integrable net, and we deduce that is a holonomic biharmonic hypersurface iff it is minimal
Causes of Death and Screening for Toxicants and Hemopathogens of European Hedgehogs (Erinaceus europaeus) from a Wildlife Rehabilitation Center in Northern France
No full textInternational audienceTo understand the dynamics of a pathogen in an animal population, one must assess how the infection status of individuals changes over time. With wild animals, this can be very challenging because individuals can be difficult to trap and sample, even more so since they are tested with imperfect diagnostic techniques. Multi-event capture-recapture models allow analysing longitudinal capture data of individuals whose infection status is assessed using imperfect tests. In this study, we used a two-year dataset from a longitudinal field study of peridomestic wild bird populations in the United Arab Emirates during which thousands of birds from various species were captured, sampled and tested for Newcastle disease virus exposure using a serological test. We developed a multi-event capture-recapture model to estimate important demographic and epidemiological parameters of the disease. The modelling outputs provided important insights into the understanding of Newcastle disease dynamics in peridomestics birds, which varies according to ecological and epidemiological parameters, and useful information in terms of surveillance strategies. To our knowledge, this study is the first attempt to model the dynamics of Newcastle disease in wild bird populations by combining longitudinal capture data and serological test results. Overall, it showcased that multi-event capture-recapture models represent a suitable method to analyse imperfect capture data and make reliable inferences on infectious disease dynamics in wild populations
TWENTY-THREE PEDIATRIC CASES OF CITROBACTER KOSERI MENINGITIS IN THE LAST 20 YEARS: STILL A DRAMATIC PROGNOSIS
No full textInternational audienceAmong 7578 cases of pediatric bacterial meningitis recorded in France (2001–2021), including 1313 neonatal cases, 23/7578 (0.3%) and 18/1313 (1.4%) were due to Citrobacter koseri. Median age was 11 days. About 63.6% of patients were hospitalized in intensive care unit. Cerebral abscesses were observed in 77.8% and the mortality rate was 22.7%
Transfert de microplastiques via le réseau d’assainissement unitaire : des dépôts au sein du réseau aux rejets urbains de temps de pluie
No full textInternational audienceAlthough it is recognized in the literature that urban wastewater carries a significant load of microplastics (MP), the contamination of deposits in sewer networks and combined sewer overflows (CSO) has remained unexplored until now, despite potentially significant contamination. Concentrations of between 5 × 103 and 178 × 103 particles/kg of dry sediment were observed in deposits, indicating that some of the microplastics carried by wastewater settle. Irrespective of the polymer considered, the sedimentation of some of the microplastics within the network could be linked to wastewater flow conditions, but also to interactions with other particles in the wastewater, and/or to the formation of hetero-aggregates with other mineral or organic particles, whether or not coated with biofilm. These phenomena lead to the formation of a large stock within the network, and the associated risk of transfer during rainy events due to the resuspension of these sediments. MP concentrations in the CSO fluctuate between 67 and 392 particles/L, and no clear relationship between MP concentration and the proportion of wastewater or stormwater or with other physico-chemical parameters, was demonstrated. This suggests that the contamination of CSO is complex and may depend on many other factors. Among these factors, the resuspension of deposits within the network could play a key role. Considering that 21 million m3 of CSO are discharged into the Seine every year and the minimum and maximum concentrations, an annual flow of particles was estimated at between 1.4 × 1012 and 8.2 × 1012 particles/year, a relatively large flow compared with the flows discharged by wastewater treatment plants (from 2,4 × 1011 to 2,3 × 1013 particles/an or downstream of the Paris conurbation (1,1 × 1013 particles/an).S’il est reconnu dans la littérature que les eaux résiduaires urbaines véhiculent une charge en microplastiques (MP) importante, la contamination des dépôts de réseaux d’assainissement et des rejets urbains de temps de pluie restait jusqu’alors inexplorée, malgré une contamination potentiellement importante. Les concentrations observées pour les dépôts (entre 5 × 103 et 178 × 103 particules/kg de sédiment sec) témoignent en effet qu’une partie des microplastiques véhiculés par les eaux usées peut sédimenter. Indépendamment du polymère considéré, la sédimentation d’une partie des microplastiques au sein du réseau pourrait être liée aux conditions d’écoulement, mais aussi aux interactions avec les autres particules des eaux usées, et/ou à la formation d’hétéro-agrégats avec d’autres particules minérales ou organiques revêtues ou non de biofilm. Ces phénomènes conduisent à la formation d’un stock important au sein du réseau, et au risque associé de transfert lors d’événements pluvieux en raison de la remise en suspension de ces sédiments. Les concentrations en MP dans les rejets urbains de temps de pluie (RUTP) fluctuent entre 67 et 392 particules/L, et aucune relation claire entre la concentration en MP et la proportion d’eaux usées ou d’eaux pluviales dans les RUTP, ni avec d’autres paramètres physico-chimiques n’a pu être mise en évidence. Cela suggère que la contamination des MP dans les RUTP est complexe et peut dépendre de nombreux autres facteurs. Parmi ces facteurs, la remise en suspension des dépôts au sein du réseau pourrait jouer un rôle clé. En considérant que 21 millions de m3 de RUTP sont déversés en Seine chaque année et les concentrations minimales et maximales, un flux annuel de particules a été estimé entre 1,4 et 8,2 × 1012 particules/an, flux relativement conséquent au regard des flux rejetés par les stations d’épuration (entre 2,4 × 1011 et 2,3 × 1013 particules/an) ou à l’aval de l’agglomération parisienne (1,1 × 1013 particules/an)