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Bourgogne - Franche-Comté, Nièvre, Entrains-sur-Nohain "1 Place Saint-Cyr". Investigations à proximité de la Porte Saint-Cyr: Rapport de diagnostic archéologique
No full textThe role of different exogenous NO concentrations on C and N biogeochemistry of an agricultural soil
No full textInternational audienceAbstract The signaling compound nitric oxide (NO) might play an important, yet unquantified role in mediating soil biogeochemical Carbon and Nitrogen cycles. This study quantified the effects of different soil-typical exogenous NO concentrations on the microbial community, on fertilizer N turnover, and on C and N trace gas fluxes of agricultural soil. For this, we repeatedly established soil NO concentrations of either 0, 200, 400, and ppbv˗NO in soil mesocosms for in total of 12 days, followed by high-resolution automated measurements of CO 2 , NO, CH 4 , and N 2 O fluxes, molecular analysis of microbial community composition and 15 N-isotope-tracing based assessment of fertilizer N turnover. We found no effects of different NO levels on microbial communities and CO 2 , CH 4 , and NO fluxes. However, at 200 ppbv concentration, exogenous NO promoted microbial assimilation of fertilizer N. In contrast, at 400 ppbv˗NO concentration, microbial biomass N was reduced, and microbial uptake of fertilizer N was inhibited, accompanied by a 33% reduction of N 2 O emissions. This suggested a promoting effect of 200 ppbv˗NO on the physiology of cells involved in heterotrophic microbial N turnover, probably reinforcing the role of cell-endogenous NO. In contrast, the higher exogenous NO concentrations of 400 ppbv seemed to inhibit heterotrophic microbial inorganic N assimilation, with however no increase in N 2 O emissions due to detoxification mechanisms. In conclusion, our pioneering study provides first insights into impacts of exogenous NO on soil C and N biogeochemistry in natural soil systems and reveals a NO concentration-dependent regulation of microbial N retention
Produire des légumineuses à graines pour des filières durables : Adaptation aux évolutions du climat
No full textInternational audienceProduire des légumineuses à graines pour des filières durables4</div
In Situ Growth of Lanthanide Coordination Polymers on Oxide Glass and Optical Fibers: A Promising Material for Chemical Sensing
No full textInternational audienc
Geometric modelling of 3D pore space using curve skeleton: Application to computational microbiology of soil organic matter mineralization
No full textInternational audienceRecent advances in 3D X-ray Computed Tomography (CT) sensors have stimulated research efforts to unveil the extremely complex micro-scale processes that control the activity of soil microorganisms. Classical methods for the numerical simulation of biological dynamics using meshes of voxels, such as the Lattice Boltzmann Method (LBM), tend to require long computation times. The use of more compact geometrical representations of the pore space can drastically decrease the computational cost of simulations. Recent research has introduced basic analytic volume primitives to define piece-wise approximations of the pore space to simulate drainage, diffusion, and microbial mineralization of organic matter in soils. Such approaches work well but a drawback is that they give rise to significant approximation errors caused by imposing a priori shapes to represent the pores. In the present article, another alternative is proposed, where pore space is described by means of geometrically relevant connected subsets of voxels (regions) regrouped on the basis of the curve skeleton (3D medial axis). The curve skeleton has been adopted to characterize 3D shapes in various fields (e.g., medical imaging, material sciences, etc.). The few publications that have used it in the context of soils have dealt exclusively with the determination of pore throats. This technique is used mostly to describe shape and not to partition it into connected subsets like in the present work. Here, the pore space is partitioned by using the branches of the curve skeleton, then an Attributed Relational Graph (ARG) is created in order to simulate numerically the microbial mineralization of organic matter, including the diffusion of by-products. Each node of the ARG is attached to an element of the partition (pore) and each arc to an adjacency relationship between pores (connectivity). The graph is valuated in the sense that the attributes related both to geometry and dynamic are linked to nodes and arcs. This new representation can be used for graph-based simulations, which are different from voxel-based simulations
Dynamics of solutions in the 1d bi-harmonic nonlinear Schrödinger equation
No full textInternational audienceWe consider the one dimensional 4th order, or bi-harmonic, nonlinear Schrödinger (NLS) equation, namely, , , and investigate the dynamics of its solutions for various powers of , including the ground state solutions and their perturbations, leading to scattering or blow-up dichotomy when , or to a trichotomy when . Ground state solutions are numerically constructed, and their stability is studied, finding that the ground state solutions may form two branches, stable and unstable, which dictates the long-term behaviour of solutions. Perturbations of the ground states on the unstable branch either lead to dispersion or the jump to a stable ground state. In the critical and supercritical cases, blow-up in finite time is also investigated, and it is conjectured that the blow-up happens with a scale-invariant profile (when ) regardless of the value of of the lower dispersion. The blow-up rate is also explored
Personalized baseline and residual TMTV influence treatment response and outcomes in relapsed/refractory lymphomas: results from the GATA study
No full textInternational audienceTotal metabolic tumor volume (TMTV) at baseline becomes a key biomarker in several lymphoma subtypes. Variability in segmentation methods such as 41%SUVmax and SUVmax > 4 has limited its clinical application. Additionally, immune-checkpoint-inhibitors introduced challenges in response assessment due to pseudoprogression, complicating the use of traditional metrics. This study investigates the prognostic impact of baseline- and residual-TMTV and introduces a novel personalized-liver-based-threshold (pTMTVliver) to enhance precision in patient stratification. Methods: We analyzed 91 patients with relapsed/refractory diffuse-large-B-cell lymphoma and follicular lymphoma from the GATA trial, comparing patient's outcome according to three segmentation methods: TMTV41%, TMTV4, and pTMTVliver. pTMTVliver used a threshold of 200%SUVmeanliver aligning with 125%SUVmaxliver to enhance standardization and reduce variability. Results: Baseline-TMTV significantly influenced prognosis with higher TMTV correlating with shorter PFS and OS (p < 0.0001 for all methods). Residual-TMTV, particularly with pTMTVliver and TMTV4, stratified no-CMR patients with the lowest predictive errors and better predictive accuracy compared to TMTV41% Multivariate analyses confirmed residual-pTMTVliver as superior for prognostic performance for PFS (HR:5.10; C-index:0.724) and OS (HR:4.00; C-index:0.853) compared to TMTV4 and Deauville Score (DS). The DS alone did not fully capture the heterogeneity of outcomes of DS4-5 patients. Conclusion: Baseline- and residual-TMTV strongly influence prognosis and response in lymphoma patients. The novel personalized pTMTVliver method offers improved accuracy of patient stratification, particularly for those with DS4-5, providing more reliable risk assessment. Larger cohorts are needed to validate these findings and optimize residual-TMTV-based clinical applications
Blandine Pennec, Les Discours de crise sanitaire (Covid-19) – Approches linguistiques
No full textInternational audienc
L’hiver 1954
No full textEn France, les Bureaux de Bienfaisance ont été remplacés par les Bureaux d'aide sociale en 1953, puis par les Centres Communaux d'action sociale (CCAS) en 1986 faisant disparaître l'action de « bienfaisance ».Créés en 1796, les « Bureaux de Bienfaisance » faisaient débuter l'action en faveur des plus démunis : une action enfin prise en charge par l'Etat, et non plus seulement par l'Eglise catholique au seul titre de la charité. Parallèlement à ces « Bureaux de Bienfaisance » relatifs à l'assistance, le développement des mécanismes de prévoyance dans la première moitié du XXe siècle aboutit en 1945 à la création de la Sécurité Sociale.</div