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MiCoReCa (Microbiome Community Resource Catalogue) - Towards Centralized Curation And Integration Of Microbiome Bioinformatics Resources
No full textThe rapid growth of microbiome research has led to the development of numerous bioinformatics tools and databases, but information about them remains fragmented across disparate, often outdated cataloging efforts, hindering resource discovery and utilization. To address this critical gap, the ELIXIR Microbiome Community proposes the development of MiCoReCa (Microbiome Community Resource Catalogue), a comprehensive, dynamic, open-access catalogue of microbiome-related bioinformatics resources (tools, workflows, training, standards, and databases). Leveraging our community's expertise, this initiative will utilize standardized ontologies like EDAM and cross-reference established platforms like bio.tools and WorkflowHub to create a centralized, findable inventory. A key feature is the community-driven process for identifying and curating missing ontological terms and metadata, ensuring MiCoReCa's accuracy and relevance in collaboration with partner platforms. Furthermore, the catalogue will integrate links to training materials from TeSS to support appropriate tool usage, and connect with OpenEBench for benchmarking capabilities. This project will not only provide a vital resource for the microbiome field, enhancing research efficiency and reproducibility, but will also establish a sustainable, adaptable infrastructure potentially applicable to other ELIXIR Communities. This effort represents a significant contribution by the ELIXIR Microbiome Community to streamline microbiome bioinformatics
Machine-learning techniques for model-independent searches in dijet final states
No full textInternational audienceAnomaly detection methods used in a recent search for new phenomena by CMS at the CERN LHC are presented. The methods use machine learning to detect anomalous jets produced in the decay of new massive particles. The effectiveness of these approaches in enhancing sensitivity to various signals is studied and compared using data collected in proton-proton collisions at a center-of-mass energy of 13 TeV. In an example analysis, the capabilities of anomaly detection methods are further demonstrated by identifying large-radius jets consistent with Lorentz-boosted hadronically decaying top quarks in a model-agnostic framework
Characterization of the quantum state of top quark pairs produced in proton-proton collisions at = 13 TeV using the beam and helicity bases
No full textInternational audienceMeasurements of the spin correlation coefficients in the beam basis are presented for top quark-antiquark () systems produced in proton-proton collisions at = 13 TeV collected by the CMS experiment in 20162018, and corresponding to an integrated luminosity of 138 fb. The system is reconstructed from final states containing an electron or muon, and jets. Together with the previously reported results in the helicity basis, these measurements are used to decompose the system into the Bell and spin eigenstates in various kinematic regions. The spin correlation coefficients are also used to evaluate properties of the quantum state, such as the purity, von Neumann entropy, and entanglement. All results are consistent with standard model predictions
Development of a method for conditioning high level radioactive waste from NaCl-MgCl2 molten salt reactors
No full textInternational audienc
Adjusting the Energy Levels of HgTe and InAs Nanocrystals with Alkali Ions
No full textInternational audienceThe photodiode stack is the most effective design geometry for integrating colloidal nanocrystals (NCs) into optoelectronic devices dedicated to light emission and detection. Traditional designs rely on determining the absolute energy band alignment, followed by selecting suitable materials to transport charges (with energy levels resonant to the active material's bands). Because of this method's inherent limitations, we propose to explore an alternative approach where alkali metals are used to tune the absolute energy levels of the optically active layer. We illustrate this concept using lithium and caesium deposition onto narrow band gap NC films (i.e., HgTe and InAs), which are relevant materials for infrared optoelectronics. Our results show that work function shifts up to 0.9 eV can be achieved and that smaller alkalis are more effective at generating this shift. However, different behaviors are observed for HgTe and InAs. In the case of II-VI materials, the alkali acts as a pure dipole (i.e., no shift in the core level), and the film behaves as a bulk effective medium (i.e., no evidence of alkali intercalation). For III-V NCs, the alkali plays a dual role as both a dipole and a redox agent, making the alkali's effect dependent on the film's surface-to-volume ratio and the size of the alkali
Finite Element Simulation of NMC Particle Fracture during Calendering: a Route to Optimize Electrode Microstructures
No full textBeyond active material intrinsic properties, the electrode manufacturing process is a crucial step to reach high energy density and long-life of Li-ion batteries. In particular, very high pressures are applied to the electrode during the calendering step, that directly influence the microstructure and the electrochemical performances. This article reports the first calendering simulation of a NMC cathode using a finite element method (FEM), including the post-fracturation behaviour of the secondary NMC particles. Calibrated with nano-indentation experiments, the mechanical model provides stress-strain predictions fully consistent with experimental data. On assemblies up to 100 particles, simulations reveal three calendering regimes along compression: particle rearrangement, moderatepressure fracturing, and complete crushing. The model shows the strong sensitivity of the electrode microstructure to the calendering pressure level, and can thus be used as a guidance in the multi-criteria optimization of the manufacturing process
Development and validation of an interface for automated image acquisition during high-temperature environmental scanning electron microscopy experiments
No full textInternational audienceAn interface that enables automatic image acquisition during high-temperature experiments in an environmental SEM is developed. It is optimized to work on multiple regions of interest at multiple magnifications, performing image focusing (focus and astigmatism) and automatic recentering of regions of interest. Its operation has been validated by monitoring two regions of interest of a nickel-based superalloy undergoing oxidation at 950°C at different magnifications. Recording series of images at different magnifications on different regions of interest makes it possible to qualify the behavior of different areas of the sample in a single operation and/or to validate the reproducibility of the observations
Microstructural transition across interlayer ultrasonic impact peened interfaces in hybrid additive manufacturing of 316L stainless steel
No full textInternational audienc
Synthèse de nanosphères d'allophane bien définies
No full textInternational audienceWell-defined allophane nanospheres, with internal and external diameters of 3.0 and 3.9 nm, respectively, were successfully synthesized and characterized by cryo-TEM, SAXS, and IR spectroscopy. In addition, we propose a refined structural framework, clarifying the coexistence of open and closed imogolite-local structures, which are commonly grouped together under the term allophane.Des nanosphères d'allophane bien définies, avec des diamètres interne et externe de 3,0 et 3,9 nm respectivement, ont été synthétisées avec succès et caractérisées par cryo-TEM, SAXS et spectroscopie IR. Nous proposons un cadre structurel raffiné, clarifiant la coexistence de structures locales imogolite ouvertes et fermées, qui sont généralement regroupées sous le terme « allophane »
Phase-field model of equilibrium and radiation induced segregation at grain boundaries: Formalism and application to Fe Cr alloys
No full textInternational audienceWe propose a novel phase-field (PF) model to enhance the description of grain boundaries (GBs) and its effect on the solute segregation behaviour under irradiation. Conventional PF models typically treat GBs as perfect sinks for point defects (PDs) such as vacancies and interstitials, often assuming the system’s chemical potentials as homogeneous. Our approach employs a density function to represent the reduction in atomic density within GBs. Furthermore, we introduce a mixing term to account for ballistic damage, simulating the effects of PD generated by displacement cascades. This study demonstrates how our model featuring the density function correctly predicts equilibrium segregation and its impact on radiation-induced segregation (RIS) in alloys, a material widely used in the nuclear industry. Our methodology successfully reproduces the well-known “W-shape” segregation profiles, and provides insights into spinodal decomposition and ballistic mixing effects on GB segregation. This advanced PF model offers a better understanding of GBs behaviour under irradiation, potentially contributing to improved material design for nuclear applications