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International audience; In order to improve the quality of ripe mangoes by managing cultural practices and storage conditions a modeling approach was used. An existing metabolic model was updated to take specificities of mango fruit sugar metabolism, fruit respiration and transpiration into account and coupled with existing models of fruit growth in dry and fresh matter, predicted based on carbon- and water-related eco-physiological and biophysical processes, respectively (Léchaudel et al., 2015, 2017). The virtual fruit model was used to investigate the effect of cultural practices and storage conditions on several fruit characteristics that can be of interest for mango processing or fruit consumption. They included fruit fresh mass and composition of the pulp in terms of dry matter content, soluble sugars, and starch concentrations. Then, the virtual mango model was used to generate numerous simulations by combining different levels of preharvest (fruit load, irrigation, position of the fruit in the tree, harvest date) and postharvest (temperature and hygrometry) factors. Among this large number of combinations, the scenarios that produce mangoes with advantageous quality criteria, such as fruit fresh mass, dry matter content and sweetness of pulp, or number of pulp slices for drying, were selected and discussed. These scenarios could then be tested and discussed with mango industry stakeholders to assess their acceptability in a process of improving fruit quality through pre- and postharvest practices.

Aim: To propose a new multimodal imaging agent targeting amyloid-β (Aβ) plaques in Alzheimer’s disease. Materials & methods: A new generation of hybrid contrast agents, based on gadolinium fluoride nanoparticles grafted with a pentameric luminescent-conjugated polythiophene, was designed, extensively characterized and evaluated in animal models of Alzheimer’s disease through MRI, two-photon microscopy and synchrotron x-ray phase-contrast imaging. Results & conclusion: Two different grafting densities of luminescent-conjugated polythiophene were achieved while preserving colloidal stability and fluorescent properties, and without affecting biodistribution. In vivo brain uptake was dependent on the blood–brain barrier status. Nevertheless, multimodal imaging showed successful Aβ targeting in both transgenic mice and Aβ fibril-injected rats.

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International audience; We uncover a connection between two seemingly unrelated notions: lettericity, from structural graph theory, and geometric griddability, from the world of permutation patterns. Both of these notions capture important structural properties of their respective classes of objects. We prove that these notions are equivalent in the sense that a permutation class is geometrically griddable if and only if the corresponding class of inversion graphs has bounded lettericity.

Purpose: To determine sex-related differences in oxygen consumption () recovery after high-intensity exercise during childhood and adolescence. Methods: Forty-two boys and 35 girls (10–17 y) performed a 60-second all-out test on a rowing ergometer. Postexercise recovery was analyzed from (1) the recovery time constant obtained from a biexponential model (τ1) and (2) excess postexercise oxygen consumption calculated over a period of 8 minutes (EPOC8) and until τ1 was reached (EPOCτ1). Multiplicative allometric modeling was used to assess the concurrent effects of body mass or lean body mass, and age on EPOC8 and EPOCτ1. Results: EPOC8 increased significantly more in boys from the age of 14 years. However, the sex difference was no longer significant when EPOC8 was analyzed using an allometric model including body mass + age or lean body mass + age. In addition, despite a greater increase in EPOCτ1 in boys from the age of 14 years, τ1 was not significantly different between sexes whatever age. Conclusion: While age and lean body mass accounted for the sex-related differences of EPOC during childhood and adolescence, no significant effect of age and sex was observed on the recovery time constant after high-intensity exercise.

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Purpose To evaluate the time required to complete a cataract training program for first-year ophthalmology residents using the EyeSi simulator. In addition, evaluate whether the simulator improves virtual performance of cataract surgery during the program. Methods We prospectively included first-year ophthalmology residents who had no experience of cataract surgery. The EyeSi simulator was used, and residents were able to follow the cataract training program, including course A (the easiest) through to course D (the hardest). In course B and above, a “cataract challenge” is proposed to the trainee every hour of simulation. Results A total of 24 participants were included in the study. During the study period, the mean (SD) total time spent on the surgical simulator was 815.6 (174.7) minutes. All the participants completed courses A and B within a mean (SD) of 366.7 (108.0) minutes. A total of 22 residents (91.7%) residents completed course C, and 5 (20.8%) course D. The mean (SD) best score on cataract challenge was 445.6/500 (40.2; range: 330–493) and was obtained in a mean (SD) 7.6 (2.6) attempts. All the residents obtained a score ≥ 60%. The best score in cataract challenge was not correlated to the time spent to achieve courses A and B (r = -0.37, p = 0.0726). Conclusions The time required to complete a basic cataract training program is possible during the first-year residency. The scores obtained in the cataract challenge also increased during the training program and should lead to better surgery skills in these young ophthalmologists.

International audience; This paper describes an innovative method, and related equipment, developed by the authors to monitor non-invasively historic panel paintings under museum display conditions. This method permits in-depth knowledge about such artworks, allowing us to understand their reactions to climatic variations, and pro- vides objective data on which conservation decisions can be confidently based, since the data are directly obtained from the individual artwork. Since 2004, following the invitation from the Louvre Museum and the C2RMF (National Centre for Research and Restoration of French Museums), the wooden panel on which Leonardo da Vinci painted his Mona Lisa has been studied by an international research team of wood technologists and engineers, including researchers from French and Italian universities and related scientific institutions (Montpellier, Clermont Auvergne, Poitiers, Florence), to understand its mechanical, hygroscopic and shape characteristics and behaviour, to evaluate its present state, and to provide sug- gestions for optimizing its conservation conditions. Non-invasive methods and equipment were therefore devised and implemented to measure (during the annual opening day of its display case) and automat- ically monitor (during the time the display case remains closed) both the deformations that the panel undergoes (mainly produced by the inevitable small climatic fluctuations within the case) and the con- straining forces acting on the panel itself. The method and the related equipment, improved over the years, are based on miniature load cells and displacement transducers, whose outputs are automatically logged at desired time intervals, typically ranging between 30 min for monitoring during the whole year, and a few seconds for manual measurements, calibrations, and other selected events; the stored data can be downloaded both through a cable connection and wirelessly, by means of a specially developed con- nection apparatus. The panel is confined in a climate-controlled display case, which typically is opened only for a few hours once a year. Additionally, close restrictions must be respected, including absolute non-invasiveness, non-interference with the enjoyment of the artwork by the public, and compliance with strict procedures for safe and secure conservation. The implementation of this method has provided significant information about the actual behaviour of the panel during the whole year. Comparing several annual force-deformation curves, their good linearity suggests that no unacceptable stress or deformation has taken place in it, showing that the climatic conditions (air temperature and relative humidity) main- tained in the display case can be considered favourable to the conservation of the artwork. Moreover, based on the collected data, reliable Finite Element Method (FEM) models are being developed and cali- brated, with the aim of describing the mechanical behaviour of the panel and virtually evaluating the risk of damage (including the propagation of an ancient crack) deriving from external conditions or actions to which it would be unthinkable to submit the original historic artwork.

International audience; On 2 December, 2021 we recorded a sequence of drumbeat seismic events at Sangay volcano. This sequence lasted several hours and resulted in two explosive emissions whose eruptive columns reached 9 km above crater. Unexpectedly, these explosions did not produce any ash fallout in the inhabited areas around the volcano. This drumbeat sequence was produced after a series of morphological changes, including the opening of two new vents (W and N) and a landslide. These occurred during an enhanced period of ground deformation and degassing. Further analysis of satellite images allowed us to determine that this sequence was associated with the widening of the recently open vent to the north of the main crater and the extrusion of a new lava flow. Timely communication of this event to the authorities and the population was ensured by the IG-EPN by following internal protocols. The corresponding short reports reached more than 300,000 people. RESUMEN El 2 de diciembre de 2021, registramos una secuencia de eventos sísmicos tipo drumbeat en el volcán Sangay. Esta secuencia duró varias horas y dio lugar a dos emisiones explosivas cuyas columnas eruptivas alcanzaron 9 km sobre el nivel del cráter. Inesperadamente, estas explosiones no produjeron caída de ceniza en las poblaciones aledañas al volcán. Esta secuencia de drumbeat se produjo después de una serie de cambios morfológicos que incluyen la apertura de dos nuevos cráteres (W y N) y un deslizamiento. Éstos ocurrieron durante un período de mayor deformación y desgasificación. El posterior análisis de imágenes satelitales permitió determinar que esta secuencia estuvo asociada al ensanchamiento del cráter recientemente abierto al norte del cráter principal y a la extrusión de un nuevo flujo de lava. El IG-EPN se encargó de comunicar oportunamente este evento a las autoridades y a la población siguiendo los protocolos internos. Los correspondientes informes llegaron a más de 300.000 personas.

International audience; This study aims to analyze the influence of the fibrils oscillations and connections on the effective hygro-elastic behavior of the wood cell wall. For that, two different models of microstructure describing the cell wall are introduced: the model 1S, for which the fibrils are allowed to oscillate in one direction like a sine curve, and the model 2S, for which the fibrils oscillate in two directions as a helix. The effective hygro-elastic behavior of the cell wall associated with each of the two models is computed by numerical periodic homogenization. Then, we analyze the effects of the fibers oscillations on the effective behavior by making vary some parameters such as the shape ratio of the unit cell, the fibrils volume fraction, or the elastic contrast between the matrix and the fibrils. It is shown that the fibrils oscillations have a significant effect on some effective moduli of the cell wall, such as the effective shear moduli G ̃12 (for both model 1S and 2S) and G ̃13 , G ̃23 (for model 2S only).

International audience; Organic–inorganic hybrid materials were prepared by intercalation of iron 5,10,15,20 tetrakis(4-sulfonatophenyl)porphyrin complex into layered double hydroxides (ZnCr-FeTSPP LDH) and layered simple hydroxides (Zn-FeTSPP LSH) by coprecipitation. They have been characterized by ancillary techniques to compare their structural characteristics, their morphology and their ability to form films on conductive substrates in view of preparing modified electrodes for CO2 electroreduction reaction (CO2ERR). The electrochemical behavior of intercalated FeTSPP was studied by cyclic voltammetry (CV) showing the role of the nature and pH of aqueous electrolyte solutions on the FeIII/II signal. Evaluation of the CO2ERR of ZnCr-FeTSPP modified electrode was investigated by CV and preparative scale CO2 electrolysis in 0.1 M Na2SO4 aqueous solution. Whereas FeTSPP in the same electrolyte solution exhibits 18% of CO2 conversion to CO, once intercalated into ZnCr-LDH, there is no CO formation, only H2 (FY = 75%). Using the ZnCr-NO3 modified electrode, without porphyrin, the same FY of H2 was obtained. The study illustrates the problematic and the complexity of an attractive approach for the development of innovative hybrid catalysts for heterogeneous CO2ERR.

The statistical trajectory matching (STM) method was applied successfully to derive coarse grain (CG) models for bulk properties of homopolymers. The extension of the methodology for building CG models for statistical copolymer systems is much more challenging. We present here the strategy for developing CG models for styrene–butadiene–rubber, and we compare the quality of the resulting CG force fields on the structure and thermodynamics at different chemical compositions. The CG models are used through the use of a genuine mesoscopic method called the dissipative particle dynamics method and compared to high-resolution molecular dynamics simulations. We conclude that the STM method is able to produce coarse-grained potentials that are transferable in composition by using only a few reference systems. Additionally, this methodology can be applied on any copolymer system.

International audience; At odds with the large literature devoted to the fiscal discipline effects of fiscal rules, only few contributions investigate their impact on public spending. Using a large sample of 185 countries, estimations based on the entropy balancing method reveal the following causal effects: fiscal rules significantly reduce total public spending and public consumption, leave public investment mostly unaffected, and increase the public investment-to-public consumption ratio. Moreover, the type of fiscal rule and countries' level of economic development influence the way fiscal rules affect public spending. Lastly, fiscal rules' features seem to be a major driving force of the way governments change public spending-and, notably, total spending and public investment-in response to the adoption of fiscal rules. Consequently, the public investment decline during recent times should mostly be attributable to other things but fiscal rules (which sometimes even raise public investment); and increased attention should be given to the various fiscal rules' features, which may enforce or, on the contrary, weaken their fiscal discipline performances.

Non-Rigid Structure-from-Motion (NRSfM) reconstructs a deformable 3D object from the correspondences established between monocular 2D images. Current NRSfM methods lack statistical robustness, which is the ability to cope with correspondence errors.This prevents one to use automatically established correspondences, which are prone to errors, thereby strongly limiting the scope of NRSfM. We propose a three-step automatic pipeline to solve NRSfM robustly by exploiting isometry. Step 1 computes the optical flow from correspondences, step 2 reconstructs each 3D point's normal vector using multiple reference images and integrates them to form surfaces with the best reference and step 3 rejects the 3D points that break isometry in their local neighborhood. Importantly, each step is designed to discard or flag erroneous correspondences. Our contributions include the robustification of optical flow by warp estimation, new fast analytic solutions to local normal reconstruction and their robustification, and a new scale-independent measure of 3D local isometric coherence. Experimental results show that our robust NRSfM method consistently outperforms existing methods on both synthetic and real datasets., Accepted in TPAMI 2021

International audience; Data points on Riemannian manifolds are fundamental objects in many applications and fields. Representations include shapes from biology and medical imaging, directions and rotations from robots. This paper addresses the problem of nonparametric regression on shapes when only few observations are available. In particular, we consider the problem of classifying unobserved 3D open parametrized curves using a continuous stochastic process to overcome the discrete nature of observations. The proposed method has a practical objective, characterizing populations of cochlear curves. The numerical solution is geometrically simpler, extensible and can be generalized for other applications. We illustrate and discuss the successful behavior of the proposed approach with various and multiple experimental results.

International audience; Background: Intravascular lithotripsy (IVL) is a promising new technology for disrupting de-novo calcified coronary lesions (DNL) before percutaneous coronary intervention (PCI). We assessed 12-month outcomes of IVL in patients undergoing PCI for DNL or intra stent restenosis (ISR) lesions related to device underexpansion.Methods: Prospective analysis of patients in the multicentre all-comers French Shock Initiative IVL registry. The primary safety endpoints in this analysis were in-hospital and 12-month major adverse cardiovascular events (MACE: cardiac death, myocardial infarction or target vessel revascularization). The primary effectiveness endpoint was procedural success, defined as

In this paper, a novel way of modeling uncertainty on demand in the single item dynamic lot sizing problem is proposed and studied. The uncertainty is not related to the demand quantity, but rather to the demand timing, i.e., the demand fully occurs in a single period of a given time interval with a given probability and no partial delivery is allowed. The problem is first motivated and modeled. Our modeling naturally correlates uncertain demands in different periods contrary to most of the literature in lot sizing. Dynamic programs are then proposed for the general case of multiple demands with stochastic demand timing and for several special cases. We also show that the most general case where the backlog cost depends both on the time period and the stochastic demand is NP-hard.

International audience; The aim of this paper is to highlight new occurrences of tephra and cryptotephra layers from three peatbogs located southeastern from the French Massif Central in France. These tephras were evidenced using magnetic susceptibility logging, scanner imagery and chemical analyses by X-Ray Fluorescence, and characterized by their glass chemistry. Originated from the Chaîne des Puys volcanic field, these six new tephras allow for the definition of a more detailed regional tephrostratigraphic framework. Most of these tephras were deposited between ca. 13,500 and 9500 yrs cal. BP, and the last one was deposited between 6400 and 5920 yrs cal. BP. Some tephras of this framework were previously described in the Jura Mountains, the Northern Alps and the Western Swiss Plateau, and allow its correlation to the Northern European context established by previous studies.

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Glioblastoma (GBM) is characterized by exceptionally high intratumoral heterogeneity. However, the molecular mechanisms underlying the origin of different GBM cell populations remain unclear. Here, we found that the compositions of ribosomes of GBM cells in the tumour core and edge differ due to alternative RNA splicing. The acidic pH in the core switches before messenger RNA splicing of the ribosomal gene RPL22L1 towards the RPL22L1b isoform. This allows cells to survive acidosis, increases stemness and correlates with worse patient outcome. Mechanistically, RPL22L1b promotes RNA splicing by interacting with lncMALAT1 in the nucleus and inducing its degradation. Contrarily, in the tumour edge region, RPL22L1a interacts with ribosomes in the cytoplasm and upregulates the translation of multiple messenger RNAs including TP53. We found that the RPL22L1 isoform switch is regulated by SRSF4 and identified a compound that inhibits this process and decreases tumour growth. These findings demonstrate how distinct GBM cell populations arise during tumour growth. Targeting this mechanism may decrease GBM heterogeneity and facilitate therapy.

International audience; Group analysis consists of using an anatomical space as reference, transferring data such as contact location and extend of stimulation from each patient and relating them to the symptomatic effect. Analyzing past implantations should support understanding the mechanisms of action of DBS and predicting outcome in new patients. Most studies place their focus on the chronic stimulation situation, with the lead at a fixed position in the brain. This results in few data samples per patient, requiring large cohorts. On the other hand, intra-operative tests are an attractive source of data. The aim of this study was to develop a fully automated pipeline for analyzing the results of intra-operative stimulation tests of ventro-intermediate nucleus of the thalamus (Vim) for ET using high-fidelity data and exemplify the pipeline on a group of patients. Data from 19 DBS patients (6 ET, 16 PD) from the University Hospital Clermont-Ferrand (France) was used to create an MR template including patient-specific labels, resulting in a probabilistic definition of 57 deep brain structures. Data from the 6 ET patients in the group was used to create a probabilistic stimulation map (PSM). Tremor reduction was assessed during intra-operative stimulation tests using a wrist-worn acceleration sensor. These scores were combined with patient-specific electric field (EF) simulations into a 4D volume. The latter was first summarized into a weighted mean map (average of the improvement weighted by the EF norm). Voxels with low occurrence of fields (10% of max) and number of patients (2 of 6) were excluded. Secondly, the significance of the relationship between tremor reduction and electric field was estimated with Linear mixed models using patient as a random effect. Voxels in the weighted mean map with |p|>0.05 were excluded. A fully automated, reproducible workflow was established to normalize and analyze intra-operative data and allowed to identify regions with significant relationship between electric field and tremor suppression. In the future more patients will be integrated to conduct statistical verification of the identified regions.

International audience; Long-Range Frequency Hopping Spread Spectrum (LR-FHSS) is a recent modulation designed for communications from low-power ground end-devices to Low-Earth Orbit (LEO) satellites. To decode a frame, an LR-FHSS gateway must receive at least one header replica and a large proportion of payload fragments. However, LR-FHSS headers will likely be lost when there are many concurrent transmissions. In this paper, we motivate the header loss problem with an analytical model, propose a linear programming model to extract headerless frames and design a cost-effective sliding window heuristic. Simulation results show that our approach exhibits near-optimal headerless detection and extraction results while ensuring a low computational cost. The proposed method is, therefore, suitable for future LR-FHSS gateways located onboard resource-constrained LEO satellites.

International audience; In the Chaîne des Puys (CdP, France), volcanic edifices and their emissions cover the weathered conductive low-permeable basement and fill the paleo-valleys, hiding the groundwater flows. The 3D delineation of such buried watersheds can be achieved studying variations of conductivity related to primary geological contrasts as well as secondary weathering-induced contrasts.We used AEM data to delineate the geometry of the undercover volcanism-basement interface in the northern part of the CdP and derived watersheds. Despite the highly resistive volcanic cover, our processing allowed structural imaging up to a depth of investigation of 330 meters in average.The processing and inversion of AEM data highlights the interface between a strongly resistant volcanic cover (~104-105 Ω.m) and a decametric conductive weathered horizon at the top of the basement (30-300 Ω.m).We picked the weathered horizon of the basement on several resistivity profiles, to build an elevation model of its top. The newly derived watersheds noticeably differ from the ones proposed in literature.

co-auteur étranger; International audience; Topography is a fundamental factor influencing the emplacement of lava flows. We assess the impact of topographic resolution on the thermorheological PyFLOWGO model, specifically with digital elevation model (DEM) resolutions commonly available for Earth and other planetary bodies where flow modeling is relevant. We examined PyFLOWGO output parameters (e.g., channel length, core temperature, and flow velocity) to assess model sensitivity to topography in order to document model uncertainties and optimize future application. This study uses rheologic and topographic data from the Tolbachik, Russia 2012–2013 eruption as model constraints. Using moderate to lower resolution topographic data overestimates the channelized flow length by up to 35% due to differences in the distribution of slopes topographic variability at different resolutions and resulting effects on the modeled lava velocity down channel. Determining the impact of topography on thermorheological lava flow models such as PyFLOWGO is important to correctly interpret the results for channelized flows.

International audience; Background: Eating disorders (EDs) are liable to alter the disease course of bipolar disorder (BD). We explored the crossed clinical features between EDs and BD, particularly as a function of BD type (BD1 vs. BD2). Methods: 2929 outpatients attending FondaMental Advanced Centers of Expertise were assessed for BD and lifetime EDs with a semi-structured interview, and their sociodemographic, dimensional and clinical data were collected according to a standardized procedure. For each ED type, bivariate analyses were used to investigate associations between these variables and the type of BD type followed by multinomial regressions with the variables associated with EDs and BDs after Bonferroni correction. Results: Comorbid EDs were diagnosed in 478 (16.4 %) cases, and were more prevalent in patients with BD2 than in those with BD1 (20.6 % vs. 12.4 %, p < 0.001). Regression models showed no difference according to the subtype of bipolar disorder on the characteristics of patients with anorexia nervosa (AN), bulimia nervosa (BN) or binge eating disorder (BED). After multiple adjustments, the factors differentiating BD patients with versus without ED were primarily age, gender, body mass index, more affective lability and comorbidity with anxiety disorders. BD patients with BED also scored higher regarding childhood trauma. BD patients with AN also showed higher risk of past suicide attempts than those with BED. Conclusions: In a large sample of patients with BD, we found a high prevalence of lifetime EDs, especially for the BD2 type. EDs were associated with several severity indicators, but not with BD type-specific characteristics. This should prompt clinicians to carefully screen patients with BD for EDs, regardless of BD and ED types.

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International audience; Knowledge Graphs (KGs) are an essential component of neuro-symbolic AI. KG Embedding Models (KGEMs) are used to represent elements of a KG (its entities and relations) in a vector space, to enable efficient processing and reasoning over knowledge. Most KGEMs are evaluated against datasets derived from the Freebase KG: FB15k and FB15k-237. In this paper, we identify limitations in these datasets with respect to Compound Value Types (CVTs), which are nodes introduced in Freebase as a substitute for \uD835\uDC5B-ary relations. In FB15k and FB51k-237, CVTs have been removed, thereby eliminating valuable information. To evaluate whether KGEMs can learn semantically accurate representations of entities and relations in Freebase, we introduce here a new dataset named FB15k-CVT, which reintroduces the deleted CVT nodes. In a preliminary evaluation, we assess the limitations of baseline KGEMs (TransE, DistMult) in the presence of CVTs. The evaluation suggests that KGEMs based on tensor decomposition are more promising than translational models but, most of all, it calls for further experiments with KGEMs that can answer conjunctive queries or that preserve logical entailment.

The recent eruptive history of Montagne Pelée volcano was dominated by a period of vigorous basaltic andesitic magma production (36-25 ka) followed by a long period of lower activity (i.e., with less frequent and less voluminous eruptions) and a renewal of felsic magma production in the last 10 ka. The temporal succession of volcanic events that occurred during the 25-10 ka period and the timing of felsic magma production are currently poorly constrained. This study focuses on the stratigraphy and eruptive dynamics of the pyroclastic deposits emplaced immediately after 25 ka. New on-land stratigraphic correlations and radiocarbon dating measurements allow us identifying six major explosive eruptions. We use field data on tephra dispersal, thickness and grain-size distribution together with physical models of explosive volcanic plumes to estimate the eruption source parameters. Our results show that these events are VEI 4 eruptions with intermediate magnitudes (from M = 4.2 to M = 5.1) and intensities (from I = 10.6 to I = 11.6). These eruptions share several characteristics with the most recent Plinian eruptions of Montagne Pelée volcano (i.e., mass eruption rate, maximum column height, runout of pyroclastic density currents, glass composition). The tephra succession documents two phases of magma production rates. The first phase from 25 to 14 ka corresponds to a period of low activity with a magma production rate of 0.04 km3 kyr-1. The second phase from 14 to 10 ka is characterized by a significant increase of the volcanic activity with a magma production rate of 0.4 km3 kyr-1, consistent with previous estimates.

Problématique / Contexte théoriqueL’étude financée s’inscrit dans le cadre du programme SlaMOR (RnMSH, CNRS, HS3Pe-criSE). Étudiée, la mort reste déniée (Auriac-Slusarczyk, 2022). Verbaliser le trépas reste un impossible pour certaines familles (Garric et al., 2022). La mort, taboue, se redouble d’une peur de révéler ce que l’on pense authentiquement, y compris en milieu hospitalier. Enquêter dans ce milieu peut ouvrir aux chercheurs une vue sur les métiers exercés, pour exploiter une potentielle transformation (Albéro & Thievenaz, 2022). Nous avons fait l’hypothèse qu’interviewer des soignants rendrait accessibles des traces discursives pertinentes pour comprendre les raisonnements qui parfois tiennent la mort à distance. Étudier les ressentis vise à installer les humanités médicales, accompagner la transformation du métier. MéthodologieSlaMOR (Soigner la mort) repose sur une enquête multicentrique, qui recueille des paroles authentiques, adressées aux enquêteurs qui questionnent les soignants (médecins, infirmiers, aides-soignants, psychologues, cadres de santé) sur leur vécu des trépas de patients admis en service d'oncologie, de neurologie (SLA, maladie de Charcot) et/ou en soins palliatifs. Une étude des discours outillée (IraMuteq, Tropes, EMOTaix, AntConc) mixte (qualitative et quantitative), suivant les principes des théories ancrées/enracinées, analyse la verbalisation hospitalière à propos de la mort au seuil du trépas. Ce sont 37 entretiens adressés aux soignants, tous soumis au même guide d’entretien semi directif, quel que soit leur statut (médecins, infirmiers etc.) qui servent de matériau. Nous avons recherché la singularité des propos (enregistrés puis transcrits) en contrastant les services (oncologie, neurologie, soins palliatifs), puis recherché la ligne commune des paroles portant sur le mourir. La qualité humaine des paroles, telles qu’elles s’exposent au cœur du travail de soignant, débouche sur des résultats intéressants la compréhension de ces métiers relationnels. RésultatsNos entretiens forcent effectivement la référence au trépas avec force émotionnelle. Des évènements discursifs saillants repèrent une lexicalisation émotionnelle, reflétant les perceptions/ressentis ambivalents formant les raisonnements situés des interviewés. Se dévoile un regard complexe sur la mort saisie au cœur du métier. Le contraste entre services et statuts des soignants dégage des caractéristiques montrant la dissonance éthique ressentie. L'emploi direct ou euphémisé dénote ce que le travail doit à des représentations sociales déterminantes.DiscussionSe confronter à la mort installe le discours hospitalier dans des précautions déterminantes. Le travail de soignant est traversé de tensions à exploiter.Références1.Albero, B. & Thievenaz, J. (2022). Enquêter dans les métiers de l'humain. Traité de méthodologie de la recherche en sciences de l'éducation et de la formation. Dijon : Eds Raison et Passion.2.Auriac-Slusarczyk, E (2022). La mort, comment l’aborder ? Aspects sanitaires, pédagogiques, cliniques et culturels, Revue Education Santé Sociétés, ESASOS, 8(2), https://doi.org/10.17184/eac.9782813004666 3.Auriac-Slusarczyk, E, & Delsart, A. (2021) Des discours authentiques singuliers aux scénarios de formation pour les médecins : quelle méthode d’exploitation pragmatique du corpus DECLICS2016, Corpus, 22, https://journals.openedition.org/corpus/5960

International audience; The Web is a decentralised system where servers can serve a set of URIs that identify resources. A resource may have one or more representations [2]. This encourages Content Negotiation (CN), the mechanism by which a client can request a resource representation that satisfies some constraints [1, Section 12]. In the SemanticWeb, resources are described using different vocabularies. HTTP provides the means to negotiate representations that have a required media type.Similarly, semantic validation languages (e.g. SHACL) could be used to define the constraints that knowledge graphs must satisfy. If a resource were identified by a single URI (unique names assumption), this would imply that all representations would be on one server. However, this is not possible on the currentWeb, because Web standards do not assume unique names and representations are distributed in different places. We propose an approach to perform content negotiation even when representations are distributed and present in multiple locations by using equivalence links, which involves on-the-fly SHACL shape validation.

Long Range (LoRa) is a wireless modulation used to provide longrange connectivity to low-power devices of the Internet of Things (IoT). LoRa gateways use hardware chips called demodulators in order to demodulate concurrent frames on different channels or spreading factors. In this paper, we establish several theoretical results on the performance of fundamental demodulator allocating strategies. In the single gateway scenario, we first prove the optimality of the basic preemptive allocation strategy. Next, in the multi-gateway scenario, the greedy non-collaborative strategy, which is currently implemented in LoRa gateways, is shown to achieve a very large approximation ratio. As an alternative, we demonstrate that a preemptive non-collaborative strategy has an approximation ratio of 2, and furthermore, that a preemptive smartcollaborative strategy reaches an approximation ratio of 3/2, for two gateways. These seminal results imply that the current performance of multi-gateway LoRa deployments can be largely improved by the proposed collaborative demodulator allocation strategies.

Welding defect detection is still often performed by the human visual inspection or with non destructive tests. These quality inspections methods can be time consuming and can have an important error rate. In this paper, we propose an approach for the detection of welding faults through the detection of abnormal subsequences of the welding voltage signal. The approach is based on the One-Class SVM with distance substitution kernels. The One Class-SVM has been used in many works for the detection of abnormal subsequences. However, often after transforming the subsequences into a set of features. Nevertheless, finding the relevant features for anomaly detection may be challenging. Dealing with the raw subsequences in distance-based approaches, on the other hand, are known to be effective and can generalize well to different problems but they often suffer from high computational cost, which may restrict their application, especially with the need of real time predictions in an industrial context. We show in this work that the One-Class SVM can be successfully used directly with the raw subsequences. This is achieved by employing distance substitution kernels. These class of kernels has not yet gained widespread adoption for time series anomaly detection. The results show that the approach is both accurate and fast, which makes it more suitable for real-time welding monitoring. We further propose an approach for automatic diagnosis of welding defects.

International audience; Muscle loss (atrophy) is observed in several physio-pathological situations and has very harmful consequences for the patients. However, despite a thorough understanding of muscle atrophy mechanisms using rodent and human models, no effective treatment is yet available. We use a bioinspired approach from the brown bear, which is naturally resistant to muscle atrophy during winter hibernation. We previously reported that this phenotype was associated with the maintenance or activation of the BMP (Bone Morphogenetic Protein) pathway (1), which positively controls muscle mass. We have also shown that winter bear serum (WBS) displays translational effects on human myotubes by inducing hypertrophy (2). Here, we aimed at further investigating the effect of WBS on human myotubes using large-scale transcriptomic analysis (mRNA sequencing) complemented using Western-blots. We identified 24,826 genes, of which 352 were differentially expressed between human myotubes cultivated for 48h with 5% of WBS or summer bear serum (SBS). Functional annotation analysis using the Gene Ontology resource revealed significant enrichment of biological processes related to (i) muscle function, (ii) extracellular matrix remodeling and (iii) negative regulation of BMP signaling. More precisely, we observed that several BMP signaling endogenous inhibitors were down-regulated at the mRNA and protein levels. Overall, these data show that hibernating bear serum induces transcriptomic reprogramming of BMP signaling regulation in human myotubes. Furthermore, the down-regulation of BMP inhibitors suggests a reduction in the repressive processes of the BMP pathway. Further studies will investigate how this reprogramming might influence BMP signaling and/or muscle mass maintenance under catabolic conditions.

International audience; Blockchain is a type of distributed ledger. A wide range of consensus algorithms exists to reach consensus in a decentralized manner. However, most of them trade energy consumption for a degree of openness. Blockchains are primarily used for tokens and cryptocurrencies. Often the process of minting new tokens depends on actionable real world behaviors. A difficulty persists in securely translating said behavior into a decentralized blockchain. We formalize the generic concept of Proof of Behavior (PoB), and use it to create a consensus mechanism for generic permissionless blockchains.

International audience; Introduction Absolute quantification of individual metabolites in complex biological samples is crucial in targeted metabolomic profiling. Objectives An inter-laboratory test was performed to evaluate the impact of the NMR software, peak-area determination method (integration vs. deconvolution) and operator on quantification trueness and precision. Methods A synthetic urine containing 32 compounds was prepared. One site prepared the urine and calibration samples, and performed NMR acquisition. NMR spectra were acquired with two pulse sequences including water suppression used in routine analyses. The pre-processed spectra were sent to the other sites where each operator quantified the metabolites using internal referencing or external calibration, and his/her favourite in-house, open-access or commercial NMR tool. Results For 1D NMR measurements with solvent presaturation during the recovery delay (zgpr), 20 metabolites were successfully quantified by all processing strategies. Some metabolites could not be quantified by some methods. For internal referencing with TSP, only one half of the metabolites were quantified with a trueness below 5%. With peak integration and external calibration, about 90% of the metabolites were quantified with a trueness below 5%. The NMRProcFlow integration module allowed the quantification of several additional metabolites. The number of quantified metabolites and quantification trueness improved for some metabolites with deconvolution tools. Trueness and precision were not significantly different between zgpr- and NOESYpr-based spectra for about 70% of the variables. Conclusion External calibration performed better than TSP internal referencing. Inter-laboratory tests are useful when choosing to better rationalize the choice of quantification tools for NMR-based metabolomic profiling and confirm the value of spectra deconvolution tools.

National audience; As part of an activity recommendation tool dedicated to therapeutic patient education, we proposed the ORALOoS solution combining OWL2 + SWRL, augmented with the Python Owlready module. The use of the imperative code makes it possible to overcome certain limitations of expressiveness, such as the absence of negation in the SWRL rules. However, it strongly counterbalances the declarative character of the approach allowed by OWL2. While preserving this characteristic, we present a solution to replace the SWRL rules and the imperative code by a program in Answer Set Programming. This idea is not new, but few studies have led to truly operational solutions in an industrial context. Our proposal is suggested in two steps : 1) use of the Hexlite solver which gives good results in terms of declarative expressiveness but remains difficult to operate with, and 2) development of a new operational library, hybridizing OWL2 and ASP with features similar to Hexlite but easy to use.; Dans le cadre d'un outil de recommandation d'activités dédié à l'éducation thérapeutique du patient, nous avons proposé la solution ORALOoS combinant OWL2 + SWRL, augmentée du module Python Owlready. L'usage de code impératif permet de pallier certaines limitations d'expressivité, comme l'absence de négation dans les règles SWRL. Cependant, il contrebalance fortement le caractère déclaratif de l'approche permis par OWL2. Tout en préservant cette caractéristique, nous présentons une solution pour remplacer règles SWRL et code impératif par un programme en Answer Set Programming. Cette idée n'est pas nouvelle mais peu de travaux ont abouti à des solutions réellement opérationnelles dans un contexte industriel. Notre proposition est abordée en deux étapes : 1) utilisation du solveur Hexlite qui donne de bons résultats en termes d'expressivité déclarative mais reste difficile à mettre en oeuvre, et 2) développement d'une nouvelle librairie opérationnelle, hybridant OWL2 et ASP avec des fonctionnalités similaires à Hexlite mais d'un usage facilité.

International audience; A Layered Double Hydroxide (LDH) compound LDH ([Mg 2 Al(OH) 6 ] + x 2 H 2 O) intercalated with a redox active organic anion, Anthraquinone-2-sulfonate (AQS), has been envisioned as an electrode material for high power aqueous based battery. The purpose is to use this interlayer redox active molecule for the enhancement of the specific capacity at the LDH composite electrode, which should allow fast charge transfer at the negative electrode for high power storage applications. This is achieved by the reduction of AQS in charge and oxidation in discharge within a redox inactive LDH matrix. The first charge of this new material [Mg 2 Al(OH) 6 ] + [AQSO 3 ] − x 2 H 2 O leads to a capacity of 100 mAh g −1 at − 0.78 V vs Ag/AgCl (based on the weight of the active material) when operated in aqueous 1 M sodium acetate electrolyte. However, low cycling stability was observed, since a drastic loss in specific capacity occurs after the first charge. This study focuses at elucidating the mechanism behind this phenomenon via in situ UV/vis experiments. Subsequently, the dissolution of charged AQS anions into the electrolyte during the first charge of the anode has been identified and quantified. Such understanding of fading mechanism might lead to the design of improved LDH-based electrodes, which utilize redox active anions working in the positive potential range with enhanced cycling ability.

International audience; Contexte.L’étude repose sur trois enquêtes nationales croisées, notamment sur deux territoires (Auvergne/Lorraine), consistant à comprendre comment les soignants ressentent/comprennent/abordent la question du mourir, ce, durant le déroulé de la « convention citoyenne sur la fin de vie », en France.Méthodes. Chaque enquête poursuit son objectif, par entretiens interposés utilisant, pour chacune une grille singulière, et vérifiant alternativement 1. Les ressentis/perceptions en phase vécu du trépas (oncologie-neurologie, 40 entrevues), 2. Les acquis/habitus professionnels sur l’usage des directives anticipées (10 entrevues), 3. Le vécu des soignants exerçant en soins palliatifs France/Québec (en développement). Les méthodologies croisées a) psycholinguistique et pragmatique outillé par Tropes-EMOTAIX ciblant notamment les contours ambigus (épisodes de tensions) liés (ou non) à des épisodes émotionnels, b)psycho-ergonomique procédant au séquençage d’épisodes émotionnels à l’aide du codage par VR-Codes, c)phénoménologique interprétative par extraction de thèmes dominants, caractérisent les données discursives transcrites de manière pluridisciplinaire (corpus global de 100 heures). Résultats.Les points de tensions face à l’inéluctable, portant sur a)la temporalité, b)les stratégies relationnelles patients-familles-équipes/soignantes, c)les rôle/place/limites du palliatif seront présentés, en se focalisant sur les recoupements vs. spécificités de chaque enquête. Des pistes d’action envisagées seront soumises en matière de formation en santé publique adaptée aux professionnels de santé, au grand publique, voire au scolaire (jeunes aidants).Discussion.Les résultats seront discutés en lien avec les apports pluridisciplinaires du colloque DIFLAMOR (https://diflamor.scienceconf.org) sur l’intérêt de poursuivre les études liant médecine, SHS et société civile et politique, en contexte français, au profit des humanités médicales.

National audience; L'ontologie SAREF (Smart Applications REFerence Ontology) est à l'honneur de l'ETSI IoT Conférence 2023. Elle est développée à l'ETSI pour contribuer à la stratégie européenne en matière de données.Lors de l'ETSI IoT Conférence, qui se tient du 4 jusqu’au 6 juillet dans les locaux de l'Institut européen des normes de télécommunications (ETSI) à Sophia-Antipolis, plusieurs présentations porteront sur l'ontologie SAREF, qui est une contribution de l'ETSI à l'interopérabilité sémantique sur les espaces européens des données.

The presentation aims to overview the landscape of Internet of Things programming platforms intended for business domain experts interested in using IoT for the digital transformation of their businesses.Choosing an IoT programming platform relies on several factors, including interoperability, security, scalability, cost, or supported functionalities. Use case requirements are confronted with each platform's guarantees to study the feasibility of IoT system deployment. With the spectrum of automation possibilities, the choice of an IoT platform also depends on its accessibility to non-technical users. For this, the support and tools platforms dedicate to programmers are crucial. What would be the required technical knowledge for developing an application? What would the learning curve be? What is the size and health of the user community? What expressiveness will the end user benefit from with graphical interfaces or domain-specific languages with natural language-like syntax? The presentation tackles all these questions and formulates some decision-support insights.The presentation includes a quick background on IoT platform characteristics and domain-specific languages they expose for programmers. Generic and Domain dedicated IoT platforms are then presented, grouped by the programming approach they adopt: model-driven, mashups or end-user programming. The presentation focuses on two IoT application domains: building automation and smart agriculture. It ends with some insights for domain experts to make informed decisions about IoT platform choices, following their use case requirements.

This presentation provides an overview of the progress on Specialist Task Force 641 Task 2, and STF 653."The overall goal of STF 641 Task 2 and STF 653 is to homogenise and facilitate the use of SAREF and existing 11 SAREF domain mapping by:• SAREF revision based on harmonisation using common ontology patterns• SAREF portal automatization (tooling) for ontologies with common patterns"This presentation will be based on the description of STF 641 and 653, progress report of Milestone A of STF 653, Stable draft TR 103 781, and initial development towards the factorization of the SAREF suite of ontologies.

Extensive fieldwork at the Cotacachi-Cuicocha Volcanic Complex (CCVC, North of Ecuador) resulted in a new collection of geological data including cartography, chronology, petrography, geochemistry, and morphology. This volcanic complex is formed by a central volcano (Cotacachi: 4939 m asl, current bulk volume of 56 ± 4 km3), several peripheral domes, and a 3 km wide volcanic caldera (Cuicocha: 4.2 ± 0.1 km3). CCVC comprises three stratigraphic members: The first, Cotacachi Basal, represents the initial phase of construction, which started at 173 ± 4 ka with a basal andesitic lava flow succession (∼500 m-thick) including isolated basaltic-andesitic lavas (Verde Tola unit; NE: 113 ± 6 ka, SE: 133 ± 9 ka), the construction of some peripheral amphibole-bearing andesitic domes, such as Muyurcu and Loma Negra (138 ± 4 ka and

International audience; A numerical FEM (Finite Element Method) model was implemented to represent the mechanical state of the wooden panel of the Mona Lisa, as it is conserved in its exhibition case, and constrained in its auxiliary frame. The model is based on the integration of advanced numerical analysis and various experimental examinations carried out non-invasively on the artwork by the authors during over 15 years. This includes visual, microscopic and X-ray observations together with mechanical measurements and monitoring of panel deformations and constraining external forces. In addition to the development of non-invasive techniques to characterise the mechanical properties of the panel, the FEM model reliably evaluated the strains and stresses generated in the panel by the various actions it experiences. The paper consists of the following parts: (i) a short summary of the experimental measurements and other observations, (ii) a detailed description of the FEM numerical model, of the hypotheses it is based on, and of its advantages and limits, (iii) the main results obtained by running the model. This includes the identification of local strains and stresses, the location of most critical areas, an evaluation of the risk that the existing ancient crack may propagate, and an evaluation of safe ranges for the forces acting on the wooden panel, (iv) the validation criteria for such results, and (v) a discussion about the significance of the mechanical model.

International audience

The results of French students in national and international assessments highlight their difficulties in reading documentaries at the end of elementary school (9-11 years old). We sought to improve teaching practices in this area. While the PIRLS 2016 international survey provided its conclusions regarding the skills that French students were particularly lacking in reading and understanding documentaries, we defined our intentions: to make up for a teaching deficit due to the difficulty in defining the strategies to be taught, but also to compensate for social inequalities by teaching all students what the most advantaged among them build in their families. To do this, we had several possibilities: to transmit knowledge to teachers in order to modify their practices or, conversely, to modify their practices in order to influence their knowledge. Following Goigoux and Cèbe, we opted for the second solution. Based on the results of the research, we chose to design a device for teaching digital document reading by testing the continuous design approach in the use adapted by these researchers by designing a didactic tool, #LectureDoc, for cycle 3. In our doctoral research, we wanted to know if their approach would allow us to carry out our project successfully. Consequently, we asked ourselves three questions: - In what way is the first step of the Continuous Design in Use approach developed by Goigoux and Cèbe valid for designing a first prototype? - How can we make up for the weakness of the second stage of continuous design in use and refine the methodology for processing user feedback to improve the tool? - To what extent does the completion of the third stage of the continuous design in use approach allow us to test the effectiveness of our tool? In order to answer these questions, we have retraced the anamnesis of each of the steps of the continuous design in use of #LectureDoc. Empirical study 1 highlights the need to use literature reviews in three areas of knowledge to design a first prototype of the tool. They did not, however, exempt us from the need to resort to additional studies to achieve this. Empirical study 2 proposes a methodological contribution concerning indicators of usefulness, usability and acceptability to help improve each of the two prototypes tested and co-designed with volunteer teachers. Empirical study 3, disrupted by the Covid 19 epidemic, did not allow us to test the effects of our tool on students. However, our test, LDN v3, is a contribution. We conclude our research work, mixing didactics and design ergonomics, by likening it to a current of design didactics.; Les résultats des élèves français aux évaluations nationales et internationales mettent en évidence leurs difficultés à lire des documentaires en fin d’école élémentaire (9-11 ans). Nous avons cherché à améliorer les pratiques enseignantes dans ce domaine. Tandis que l’enquête internationale PIRLS 2016 livrait ses conclusions quant aux compétences qui faisaient particulièrement défaut aux élèves français pour lire et comprendre les documentaires, nous avons défini nos intentions : suppléer à un déficit d'enseignement en raison de la difficulté à définir les stratégies à enseigner, mais aussi, compenser les inégalités sociales en enseignant à tous les élèves ce que les plus favorisés d’entre eux construisent dans leur famille. Pour cela, nous avions plusieurs possibilités : transmettre des connaissances aux enseignants pour modifier leurs pratiques ou, à l’inverse, modifier leurs pratiques pour infléchir leurs connaissances. À la suite de Goigoux et Cèbe, nous avons opté pour la seconde solution. Nous avons choisi, en nous appuyant sur les résultats de la recherche, de concevoir un dispositif d’enseignement de la lecture documentaire numérique en mettant à l’épreuve la démarche de conception continuée dans l’usage adaptée par ces chercheurs en concevant un outil didactique, #LectureDoc, pour le cycle 3. Dans notre recherche doctorale, nous avons voulu savoir si leur démarche nous permettrait de mener notre projet à bien. Par conséquent, nous nous sommes posée trois questions : - En quoi la première étape de la démarche de conception continuée dans l’usage développée par Goigoux et Cèbe est-elle valide pour concevoir un premier prototype ? - Comment suppléer à la faiblesse de la deuxième étape de la conception continuée dans l’usage et affiner la méthodologie de traitement des retours des utilisateurs pour améliorer l’outil ? - Dans quelle mesure la réalisation de la troisième étape de la démarche de conception continuée dans l’usage permet-elle de tester l’efficacité de notre outil ? Afin de répondre à ces questions, nous avons retracé l’anamnèse de chacune des étapes de conception continuée dans l’usage de #LectureDoc. L’étude empirique 1 met en évidence la nécessité de recourir à des revues de littérature dans trois domaines de connaissances pour concevoir un premier prototype de l’outil. Elles ne nous ont cependant pas exonérée de recourir à des études complémentaires pour y parvenir. L’étude empirique 2 propose un apport méthodologique concernant des indicateurs d’utilité, d’utilisabilité et d’acceptabilité pour aider à l’amélioration de chacun des deux prototypes testés et co-conçus avec des enseignants volontaires. L’étude empirique 3, perturbée par l’épidémie de Covid 19, ne nous a pas permis de tester les effets de notre outil sur les élèves. Toutefois, notre test, LDN v3, constitue un apport. Nous concluons notre travail de recherche, mêlant didactique et ergonomie de conception, en l’apparentant à un courant de didactique de conception.

Antibiotics and antifungals are one of the greatest discoveries of medicine and have helped save millions of lives. However, their effectiveness is threatened by the adaptation of microorganisms that become resistant. This phenomenon is particularly related to the abnormally high consumption of antimicrobial molecules, especially in France. Even though these resistances are mainly acquired by bacteria, pathogenic yeasts such as the genus Candida do not escape the rule. Therefore, the scientific community and health services must implement as soon as possible alternatives to traditional drugs. Among these alternatives, the use of probiotic microorganisms whose antifungal potential has already been demonstrated using preclinical models (cell cultures, laboratory animals) and clinical studies is particularly promising. This is the case of the Live Biotherapeutic Microorganism Lactobacillus rhamnosus Lcr35® strain whose anti-C. albicans has been demonstrated in previous work but failed to describe the mechanisms of action. Understanding them has become a strategic need for the development of new treatments for humans.An innovative experimental approach, using the nematode model Caenorhabditis elegans, has been implemented. The aim was to simulate a fungal infection and treat it with Lcr35® using preventive and curative approaches. These were followed by means of tests of longevity and survival of the host, by the study of its transcriptome (in a targeted and global way), all in connection with the follow-up of the activity of a factor transcription, DAF-16. We thus demonstrated that Lcr35® induced a significantly increased survival of the host, including after infection by Candida. The analysis of the transcriptome of C. elegans and the use of mutant strains showed the involvement of the p38 MAPK and DAF-2 / DAF-16 signaling pathways, pathways involved in longevity and pathogen control. Also, in vitro Caco-2 intestinal cell assays showed significant inhibition of pathogen growth and adhesion by Lcr35®. These results suggest that the bacterium Lcr35® has a direct action on the pathogen causing its death but also by modulating the transcriptional response of the host via highly conserved signaling pathways. Further study, targeting the host metabolome, would allow a better understanding of the mechanisms and adapt the industrial design of LBM according to the therapeutic target.; Les antibiotiques et antifongiques constituent une des plus grandes découvertes de la médecine et ont participé à sauver des millions de vies. Cependant, leur efficacité est menacée du fait de l’adaptation des microorganismes qui deviennent résistants à leurs actions. Ce phénomène est en particulier lié à la consommation anormalement élevée de molécules antimicrobiennes, notamment en France. En dépit du fait que ces résistances soient acquises majoritairement par des bactéries, les levures pathogènes comme le genre Candida n’échappent pas à la règle. Dès lors, la communauté scientifique et les services de santé doivent mettre en place au plus vite des alternatives aux médicaments traditionnels. Parmi ces alternatives, l’utilisation de microorganismes probiotiques dont le potentiel antifongique a déjà été démontré à l’aide de modèles précliniques (cultures cellulaires, animaux de laboratoire) et d’études cliniques est prometteuse. Ceci est notamment le cas du Live Biotherapeutic Microorganism Lactobacillus rhamnosus Lcr35® dont l’activité anti-C. albicans a été prouvée lors de travaux précédents sans toutefois parvenir à décrire les mécanismes d’actions. Les comprendre est devenu un besoin stratégique pour le développement de nouveaux traitements pour l’homme.Une approche expérimentale innovante, utilisant le modèle nématode Caenorhabditis elegans, a été mise en œuvre. Celle-ci visait à simuler une infection fongique et à évaluer l’effet de Lcr35® par des approches préventive et curative. Les impacts ont été suivis au moyen de tests de longévité et de survie de l’hôte ainsi que par l’étude de son transcriptome (de manière ciblée et globale), le tout en lien avec le niveau d’activité d’un facteur de transcription central, DAF-16. Nous avons ainsi démontré que Lcr35® induisait une survie significativement augmentée de l’hôte y compris après infection par Candida. L’analyse du transcriptome de C. elegans et l’utilisation de souches mutantes ont montré l’implication des voies de signalisations p38 MAPK et DAF-2/DAF-16 impliquées dans la longévité et la lutte anti-pathogène. De plus, des tests in vitro sur cellules intestinales Caco-2 ont montré une inhibition significative de la croissance et de l’adhésion du pathogène par Lcr35®. Ces résultats suggèrent que la bactérie Lcr35® a une action directe sur le pathogène en entraînant sa mort, mais également en modulant la réponse transcriptionnelle de l’hôte via des voies de signalisation hautement conservées. Une étude plus approfondie ciblant notamment le métabolome de l’hôte permettrait une compréhension plus fine des mécanismes afin d’adapter le criblage et la conception industrielle de LBM selon la cible thérapeutique.

The samarium-146 ( 146 Sm)–neodymium-142 ( 142 Nd) short-lived decay system (half-life of 103 million years) is a powerful tracer of the early mantle-crust evolution of planetary bodies. However, an increased 142 Nd/ 144 Nd in modern terrestrial rocks relative to chondrite meteorites has been proposed to be caused by nucleosynthetic anomalies, obscuring early Earth’s differentiation history. We use stepwise dissolution of primitive chondrites to quantify nucleosynthetic contributions on the composition of chondrites. After correction for nucleosynthetic anomalies, Earth and the silicate parts of differentiated planetesimals contain resolved excesses of 142 Nd relative to chondrites. We conclude that only collisional erosion of primordial crusts can explain such compositions. This process associated with planetary accretion must have produced substantial loss of incompatible elements, including long-term heat-producing elements such as uranium, thorium, and potassium.

International audience