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Transcriptomic plasticity in schistosome worms after host shift and adaptive introgression can contribute to their zoonotic potential
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First-order behavior of the time constant in non-isotropic continuous first-passage percolation
No full textConsider a homogeneous Poisson point process on () with unit intensity with respect to the Lebesgue measure. For , we define the Boolean model as the union of the balls of volume for the -norm () and centered at the points of . We define a random pseudo-metric on by associating with any path a travel time equal to its -length outside . This defines a continuous model of first-passage percolation, that has been studied in \cite{GT17,GT22} for , the Euclidean norm. For , this model is expected to share common properties with the classical first-passage percolation on the graph with a distribution of passage times of the form . The exact calculation of the time constant of this model is out of reach. We investigate here the behavior of near , and enlighten how the speed at which goes to depends on and . For instance, for , we prove that is of order with where is the number of non null coordinates of . The exact order of is also given for and . Related results are also discussed, about properties of the geodesics, and analog properties on closely related models
La politique dans le caveau. Le chronotope gothique d'Une ténébreuse affaire
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Closed-form solution and reliability analysis of deep lined tunnel behavior in anisotropic viscoelastic rock
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Experimental approach to copper production: towards a better understanding of technical processes
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Mapping idiopathic pulmonary fibrosis: how cellular niches fuel pathogenic plasma cell accumulation
No full textInternational audienceIdiopathic pulmonary fibrosis (IPF) is a progressive lung disease that transforms lung tissue into a landscape of pathological scarring and damaged alveoli. However, the mechanisms linking immune responses to fibrosis remain shrouded in mystery. Combining cutting-edge spatial transcriptomics and single-cell RNA sequencing (scRNA-seq) followed by RNA-scope and immunofluorescence validations, the study by Yang et al. [1] published in this issue of the European Respiratory Journal underscores a prominent presence of tertiary lymphoid structure (TLS)-generating plasma cells in end-stage IPF lungs. It uncovers the spatial dynamics of antibody-producing plasma cells, the intricate architecture of TLS, and novel cellular players and molecular pathways that fuel antibody accumulation and drive fibrosis. The authors identified unique subsets of mural cells and specialised fibroblasts, which create niches fostering plasma cell accumulation and antibody production
Towards the Structural Investigation of Bio-Based Blends from Functionalized Lignin for Additive Manufacturing by 1Hand 13C variable temperature Solid-State NMR.
No full textInternational audienceThis study is conducted in the framework of ANR project MAGNELIN4D aiming to develop new generationof 3D printing filaments with a high load of lignin biomass. In this context, we focus on PA1130GDA, a composite material of kraft lignin, functionalized with glycidyl allyl ether (GDA, 30 % weightratio) and of polyamide (PA11) polymer.We use variable temperature solid-state NMR for the characterization of the native lignin and its blendsto get atomic-scale information of PA11 30GDA, a polymer with functionalized lignin, at different temperaturesfrom RT to 220 ◦C. It should be noted that the last temperature is the temperature in the 3Dprinter’s extrusion nozzle.The increasing temperature leads to narrowing of signals in the 1H and 13C spectra and allows us toassign the resonances corresponding to lignin-functionalized group (GDA) and the PA11 polymer chain.Obtained variable temperature data NMR compared with both the isolated lignin and the functionalizedlignin spectra.Besides structural details, we could obtain the spectroscopic fingerprint of extruded blends with functionalizedlignin, setting the basis for further studies, which will involve other synthetic polymer, ligninfunctionalization group, and functionalized lignin ratios.This work is financially supported by ANR (Project MAGNELIN4D ANR-22-CE10-0010).Acknowledgments: Claudie Simon from UCCS Lille for providing GDA functionalized lignin, XavierFalourd from BIBS facility for valuable suggestions and comments
ÉTUDE DES COMPORTEMENTS, PRATIQUES ET REPRÉSENTATIONS DES TOURISTESET DES COMMUNAUTÉS D'ACCUEIL DANS LA STATION BALNÉAIRE DE CAP-SKIRRING(DIÉMBÉRING-SÉNÉGAL)
No full textInternational audienceIn Cap-Skirring, tourism raises a variety of issues. Interactions between tourists and locals are at the heart of socio-economic, cultural and environmental dynamics. Against this backdrop, the study set out to analyze the behaviors, practices and representations of both tourists and host communities. The results of the survey reveal that 65% of tourists are satisfied with the welcome they receive, highlighting the importance of cultural exchanges. Among locals, 77% are in regular contact with visitors. The majority view these interactions positively, despite concerns about the cost of living (61%) and other negative impacts such as prostitution and pressure on natural resources. Local stakeholders thus aspire to sustainable tourism that respects traditions and the environment, while promoting local economic development.Au Cap-Skirring, le tourisme suscite des enjeux variés. Les interactions entre touristes et autochtones sont au cœur des dynamiques socio-économiques, culturels et environnementaux. Dans ce contexte, l'étude se donne pour objectif d'analyser les comportements, pratiques et représentations des touristes ainsi que des communautés d'accueil. Les résultats de cette enquête révèlent que 65 % des touristes se disent satisfaits de l'accueil, mettant en avant l'importance des échanges culturels. Du côté des locaux, 77 % sont en contact régulier avec les visiteurs. La majorité perçoit ces interactions positivement malgré des préoccupations sur le coût de la vie (61 %) et d'autres impacts négatifs comme la prostitution et les pressions sur les ressources naturelles. Les acteurs locaux aspirent ainsi à un tourisme durable, respectueux des traditions et de l'environnement, tout en favorisant le développement économique local
Towards more efficient, more specific, and safer MRI contrast agents: a Portuguese–French collaborative journey
No full textInternational audienceAlthough complexes of the paramagnetic Gd(III) ion have been used with great success for the past 40 years to enhance image contrast in magnetic resonance imaging (MRI), important challenges such as improving the relaxation efficacy, the specificity, the safety, and the environmental impact of these agents remain in this field. Thanks to a collaborative effort between the Centre of Molecular Biophysics in Orléans, France and the Coimbra Chemistry Centre - Institute of Molecular Sciences in Coimbra, Portugal, there have been important advances in the chemistry of MRI probes. The authors have developed rigid, medium-sized, and bishydrated Gd(III) complexes specifically optimized for high-field applications with successful validation in vivo. For the specific targeting of amyloid peptides implicated in many pathologies such as Alzheimer’s disease and diabetes, they have designed benzothiazole-derivative metal chelates with detection potential in MRI, optical, and nuclear imaging modalities. The authors have gained valuable insights into the aggregation behavior of these complexes in solution and how this affects peptide binding affinity. More recently, manganese porphyrin complexes have been investigated with the objective of visualizing the tissue redox state based on the Mn(II)/Mn(III) redox switch, which can be followed not only in classical H detection but also in F MRI