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Ribosomal protein L5 (RPL5/uL18) I60V mutation is associated to increased translation and modulates drug sensitivity in T-cell acute lymphoblastic leukemia cells
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Evaluating solid-state neutron detectors for measuring 14 MeV neutrons at high temperatures
No full textInternational audienceSilicon Carbide 4H Polytype (4H-SiC) and Diamond wide bandgap semiconductors are promising detector materials for fusion environments. Threshold energy nuclear reactions provide information on the energy of impinging fast neutrons and the combination of low intrinsic carrier concentration with high thermal conductivity makes these semiconductors suitable for high-temperature applications, especially for neutron monitoring in tritium production through ITER breeding blankets. While the carrier properties of SiC and Diamond offer interesting charge collection dynamics from room temperature up to 200 °C, the stability of their detection performance at high temperatures above 200 °C remains to be confirmed. To investigate this, we conducted a measurement campaign in a fast neutron field representative of fusion reactors at the GENESIS (Generator of Neutrons for Science and IrradiationS) research platform of LPSC (Laboratoire de Physique Subatomique et de Cosmologie) laboratory in Grenoble, France. Both 4H-SiC and Diamond sensors were irradiated with 14 MeV fast neutrons from a D-T neutron generator while encapsulated in a heating device, recording current signals from room temperature up to 500 °C. Using a direct measurement method of charge carrier collection dynamics as a function of applied bias voltage and temperature by pulse shape analysis provided information on velocity drift and collected charge. The results offer a first representative study of charge carrier mobility behavior with increasing temperature up to 500 °C. The stability of performance in terms of CCE (charge collection efficiency) has been demonstrated for SiC from room temperature up to 500 °C, while Diamond experiences a CCE drop of 60% between 200 °C and 300 °C
Exploration of UHS scalability by SPS approach: Multiphysics simulation, critical dimensions, mechanisms and properties
No full textInternational audienceUltrafast High-Temperature Sintering (UHS) enables near-instantaneous densification of ceramics but is limited by part size, wall thickness, and cracking due to thermal inhomogeneities. This work introduces a scalable UHS approach using a modified Spark Plasma Sintering (SPS) chamber with a large working volume (∼113 cm3) and precise control, enabling the sintering of complex ceramic parts up to 30 mm. Direct Ink Writing (DIW) is employed to shape and debind components efficiently while preserving UHS advantages. A parametric study identifies optimal heating rates and critical wall thicknesses (≤1 mm) to minimize thermal stress. Finite element simulations link thermal gradients to stress development, offering predictive capability for complex geometries. The results reveal that organic binder decomposition strongly affects grain growth and residual porosity under ultrafast heating. This work demonstrates the feasibility of industrially scalable UHS and provides key insights for microstructure control and simulation-guided process design
Atmospheric specifications for infrasound studies: 2. the added value of a high-top model, UA-ICON
No full textInternational audienceInfrasound monitoring activities that deal with long-range acoustic propagation, as within the Comprehensive Nuclear-Test-Ban Treaty’s (CTBT), need accurate and operational modeling of the atmosphere up to the lower thermosphere. Yet, operational meteorological products issued by weather services are topped at around 80 km altitude with a sponge layer starting in the stratosphere. This prevents reliable simulation of atmospheric dynamics where infrasound waveguides form. Hence, investigating higher-top atmospheric models enabling simulations at typical operational horizontal resolutions ( km) are of high interest to improve the description of the propagation medium, which is needed to localize and characterizes acoustic sources of interest. The extension of the ICOsahedral Non-hydrostatic (ICON) model to the upper-Atmosphere, UA-ICON with a model-top of 150km, is run at the ICON operational horizontal resolution. Simulations are compared with lidar observations at three different sites and with operational analyses. We demonstrate the better performance of the UA-ICON simulations compared to operational models in the mesosphere, especially for the temperature field while it is less clear for the winds. This is achieved by tuning the non-orographic gravity wave (GW) parameterization coefficient that drives the saturation and breaking of the waves. Additionally, infrasound propagation simulations are performed using UA-ICON atmospheric specifications. For the two case-studies, one at high latitudes and one in tropical regions, we demonstrate the added value of the UA-ICON with a tuned GW parameterization, while also illustrating how infrasound can contribute to model validation and tuning in the upper-atmosphere
MARL-based Traffic Management in Communication Networks: Randomized vs. Traffic-Based Agent Deployment
No full textInternational audienceThe rapid growth of consumer applications such as video streaming, cloud gaming, Augmented Reality/Virtual Reality (AR/VR), and Internet of Things (IoT) deployments has intensified the demand for intelligent and adaptive congestion control in communication networks. Existing centralized congestion control solutions often struggle with scalability and responsiveness under highly dynamic traffic conditions. In this paper, we present a decentralized traffic engineering framework based on Multi-Agent Reinforcement Learning (MARL), tailored to optimize routing and traffic balancing in real time. The framework introduces two types of agents: (i) Routing Agents, which dynamically adjust link weights to steer flows across alternative paths, and (ii) Balancing Agents, which regulate traffic splitting ratios over precomputed multi-path routes. Beyond agent design, we address a key yet underexplored challenge: agent placement strategy. We compare random deployment versus traffic-aware deployment (based on node degree) and evaluate their effectiveness in mitigating congestion. Using an OMNeT++ simulation environment with realistic consumer traffic patterns on the Abilene topology (a well-known Internet2 research network), we test the framework across diverse congestion scenarios. Results show that traffic-aware placement consistently improves throughput, reduces latency and packet loss compared to both random placement and traditional Equal-Cost Multi-Path (ECMP) routing baselines. These findings highlight the potential of MARL-driven, placement-aware agents to support future consumer network-ing services requiring low-latency, high-reliability, and scalable resource management
Ultrafast Printing and Sintering: Breaking Manufacturing Speed Barrier
No full textInternational audienceHigh speed and automation are key aspects of Industry 4.0. With the advent of Ultrafast High Temperature Sintering (UHS), the concept of ultrafast, energy‐efficient fabrication is becoming a reality. However, this fast sintering approach is limited by the long prior stages of production, including printing, drying, and debinding. In this work, a significant breakthrough has been achieved to enable ultrafast printing under specific rheological conditions using Direct Ink Writing (DIW), while drastically reducing both drying and debinding times. A low‐organic content suspension was developed, enabling the ultrafast extrusion of self‐supported, thin‐walled complex parts with nozzle sizes down to 0.4 mm. With this formulation, drying and debinding times were significantly reduced, from several days to just 20 and 30 min, respectively. The sintering process, based on UHS, was successfully adapted through Pressureless Spark Plasma Sintering (P‐SPS), allowing the densification of large and complex parts. A comprehensive multiphysics simulation tool for large‐scale UHS was developed, capable of capturing the complex thermal irradiation environment and its impact on final microstructures. Finally, the concept of a continuous ultrafast manufacturing line is introduced and demonstrated, showcasing the potential for producing complex ceramic parts within just a few hours
photoD with Rubin's Data Preview 1: first stellar photometric distances and deficit of faint blue stars. Stellar distances with Rubin's DP1
No full textInternational audienceAims: We investigate the utility of Rubin's Data Preview 1 for estimating stellar number density profile in the Milky Way halo. Methods: Stellar broad-band near-UV to near-IR photometry released in Rubin's Data Preview 1 is used to estimate distance and metallicity for blue main sequence stars brighter than in three 1.1. sq.~deg. fields at southern Galactic latitudes. Results: Compared to TRILEGAL simulations of the Galaxy's stellar content by (Dal Tio, 2022), we find a significant deficit of blue main sequence turn-off stars with . We interpret this discrepancy as a signature of a much steeper halo number density profile at galactocentric distances kpc than the cannonical profile assumed in TRILEGAL simulations. Conclusions: This interpretation is consistent with earlier suggestions based on observations of more luminous, but much less numerous, evolved stellar populations, and a few pencil beam surveys of blue main sequence stars in the northern sky. These results bode well for the future Galactic halo exploration with Rubin's Legacy Survey of Space and Time
A Framework for Minimizing the Impact of Wet Antenna Attenuation on Rainfall Estimates Provided by Commercial Microwave Links
No full textInternational audienceThe compensation of the extra attenuation introduced by wet antennas is crucial to get reliable rainfall intensity estimates from the data collected by commercial microwave links (CMLs). This study reviews the available wet antenna attenuation (WAA) models and proposes a new framework for calibrating WAA model parameters, based on rain gauge measurements (assumed as ground truth). The framework has been applied to the data measured by 86 CMLs located in the Seveso River basin (Northern Italy) during 44 rainy days in 2019-2020. As most WAA models are basically equivalent in spite of different formulations, we selected only a subset, including the Schleiss-Rieckerman-Berne model (SRB) and the Valtr-Fencl-Bareš (VFB) model, the latter in the versions with the original parameter values and with the parameters calibrated over our CML data (VFBm). We found that WAA increases with rainfall intensity, as predicted by the VFB model, and it is weakly dependent on link frequency. We derived two sets of optimum WAA model parameters for the Ka-band (17-23 GHz) and the Q-band (37-43 GHz), respectively. WAA values are up to 4 dB at heavy rainfall intensities (50 mm/h) in the Q-band. The VFBm model performs better than VFB and outperforms SRB, when assessed over the entire set of CML data and over different classes of CMLs (based on distance to the neighbor rain gauge, frequency, and path length) or, again, over different classes of rainfall intensity.</div
Distribution trends of soil fauna with different body sizes and feeding habits across altitudinal climate zones on Mount Gongga, China
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First evidence of the decay
No full textInternational audienceThe first search for the decay in the range is performed using data from proton-proton collisions collected by the LHCb experiment at centre-of-mass energies of 7, 8, and 13 TeV, corresponding to an integrated luminosity of 9 fb. The photons are reconstructed through their conversion into an electron-positron pair, which significantly improves the mass resolution of the reconstructed decays with respect to decays with an unconverted photon. A signal excess with a significance of 3.5 standard deviations is measured, constituting the first experimental evidence for this decay. In the range , the ratio between the branching fractions of the signal decay and the favoured decay is measured to be where the first uncertainty is statistical and the second is systematic. This measurement is consistent with the value predicted in the Standard Model. In the range , the ratio is measured