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Discovery of two new millisecond pulsars towards the Galactic bulge
No full textInternational audienceThe mysterious Galactic Center Excess of gamma rays could be explained by a large population of millisecond pulsars hiding in the Galactic bulge, too faint to be detected as individual high-energy point sources by the Fermi Large Area Telescope, as well as too fast and too dispersed to be detected in shallow radio pulsation surveys. Motivated by an innovative candidate selection method, we aim at detecting millisecond pulsars associated with the Galactic Center Excess by carrying deep radio pulsation searches towards promising candidates detected in the inner Galaxy, in X rays by Chandra, and in radio or gamma rays by the Very Large Array or Fermi. We conducted deep radio observation and follow-up campaigns with MeerKAT, the Murriyang and the Green Bank telescopes towards 9 X-ray candidate sources. We here report the detection of two new millisecond pulsars, including a black widow candidate, towards the Galactic bulge: PSRs J1740-2805 and J1740-28. These discoveries double the number of MSPs discovered within the innermost 2 degree from the Galactic center
Démonstration de sauts orbitaux multiples dans un récepteur électrodynamique non linéaire à double mode pour le transfert d'énergie sans fil
No full textInternational audienceThis paper introduces a rotating-magnet based electrodynamic receiver for low-frequency wireless power transfer, capable of operating in two distinct modes: an oscillating mode and a continuous rotation mode. This dual-mode capability, never demonstrated previously in similar systems, enables seamless adaptation to a wide range of input magnetic field characteristics, addressing limitations of existing systems. An analytical model is developed to characterize the system's behavior and predict its performance. Based on this model, an orbit jump strategy to force the transition between modes has been developed, simulated, and experimentally validated. Experimental validation shows that the receiver, within a bounding box of 810 mm³, achieves 16.7 mW at 135 Hz in continuous rotation mode and 4.4 mW at 47 Hz under a 1 mT field in oscillating mode
Robotic total knee arthroplasty with functional positioning safely addresses major coronal deformities: Comparable complications and survivorship
No full textInternational audienceAbstract Purpose Robotic‐assisted total knee arthroplasty (TKA) has emerged as a reliable strategy to improve surgical accuracy and enable functional alignment (FA), also referred to as functional knee positioning (FKP). However, its application in patients with major coronal plane deformities remains under‐investigated. This study aimed to evaluate complication rates, implant survival, radiographic outcomes and patient‐reported measures in patients with severe deformities undergoing robotic‐assisted TKA with FA/FKP principles compared to matched controls. Methods A retrospective comparative study was conducted on patients who underwent robotic‐assisted TKA between March 2021 and February 2023 at a single high‐volume centre. Patients with ≥15° varus or ≥10° valgus deformity were included in the study group and matched 1:1 with controls presenting neutral alignment. All procedures used the Mako robotic‐arm‐assisted system with standardised FA/FKP principles. Clinical outcomes included knee society score (KSS), forgotten joint score (FJS‐12), Kujala anterior knee pain scale (AKPS) and range of motion. Radiographic measurements and robotic data were assessed. Complications, reoperations and revision rates were analysed. Results Eighty‐eight patients (44 per group) were analysed, with a mean follow‐up of 2.8 ± 0.9 years. Complication and revision rates were comparable between groups (revision: 2.3% vs. 0%, p = 0.987). Patients with major deformities achieved higher FJS‐12 scores (83.9 ± 20.2 vs. 74.9 ± 19.0, p = 0.040), although the difference did not exceed the minimal clinically important difference (MCID = 9.9). Postoperative mHKA was less neutral in the deformity group (176.8° ± 4.7 vs. 180.0° ± 3.0, p = 0.002), without adverse impact on implant survival. Conclusions Robotic‐assisted TKA performed with FA/FKP principles appears to be a feasible option for patients with severe varus or valgus deformities. Despite residual alignment variability, complication and revision rates remained comparable to standard cases, and patient‐reported outcomes suggested greater perceived functional improvement. Level of Evidence Level III
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
Miagliano, une banlieue industrielle de montagne au cœur de la filière laine européenne
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Strain pattern and active faults' compatibility across the Western Alps revealed by 25 years of GNSS measurements
No full textUpdated GNSS solutions integrating 25 years of GNSS data allow to evaluate deformation rates of 0.1–1 mm/yr in the WesternAlps, and in particular to compare the High Durance fault (HDF) activity (internal zones) with the Belledonne Fault (BDF)(external zone). Strain rate estimates are larger across HDF (19 ± 3 nanostrain/yr EW extension) than BDF (5 ± 1 nanostrain/yr EW compression). Fault slip rates indicate dominant dextral strike-slip motion on BDF (0.2 ± 0.1 mm/yr), whileHDF exhibits major extensional motion (0.3 ± 0.1 mm/yr). These two faults represent therefore the broader kinematics of theW-Alps characterized by seismicity showing mainly extensional deformation in the internal zones (HDF) and strike-slip motionin the external zone (BDF). Finally, a rigid 3-blocks model explains 29% of the observed GNSS velocity field and confirms theHDF and BDF deformation styles and their interconnected roles in the W-Alpine deformation framework
A comprehensive analysis of the decay
No full textInternational audienceAn analysis of the decay is presented using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 8.4 fb. The full set of -averaged and -asymmetric angular observables is determined in bins of the invariant mass squared of the dimuon system, as well as the branching fraction relative to the decay. For the first time, the full set of observables pertaining to the S-wave contribution to the final state are presented and consideration is given to effects arising from the mass of the muons. The measurements of the -averaged observables and the branching fractions continue to exhibit the pattern of tensions with the Standard Model predictions that have been seen in previous analyses that use part of the dataset considered in this study. The extracted -asymmetry observables show no significant deviations from zero
Land use and management intensity shape nitrogen cycling and microbial functions, driving environmental impacts in French urban soils
No full textInternational audienceUrbanization profoundly alters soil through changes in land use and management intensity, affecting both soil functions and microbial communities. These shifts can degrade soil fertility and disrupt ecosystem processes. This study investigates how different public urban land uses -including showcase gardens, parks, tree-covered areas, roadsides, residential zones, sports fields and unused areas-influence nitrogen dynamics and microbial functions. We used a multifaceted approach combining biogeochemical measurements (NH₄ + , NO₃ -, total N), functional assays (potential mineralization, potential nitrification, potential denitrification), and molecular techniques (functional gene abundances and bacterial community profiling using Illumina MiSeq). Results showed that land use significantly influenced nitrogen cycle processes. Showcase garden areas were characterized by elevated nitrate levels, driven by fertilization and higher nitrification activity, whereas denitrification and related gene abundances were higher in parks and roadside soils. Structural equation modeling (SEM) revealed that soil organic carbon was a major driver of denitrification in most of the land uses, and pH positively influenced the abundance of ammonia-oxidizing archaea (AOA), whereas soil water retention, often reduced in compacted soils, was negatively correlated with most nitrogen variables. In terms of bacterial communities, this study revealed that bacterial functions linked to the nitrogen cycle varied according to land use. Lightly managed areas harboured more nitrogen-fixing bacteria, while intensely managed areas showed a predominance of bacteria involved in nitrification. Furthermore, the absence of any significant correlation between the multiple stages of the nitrogen cycle (mineralization, nitrification, denitrification) in intensively managed areas suggested a breakdown in nitrogen cycling, probably linked to excessive aeration, tillage and low organic matter accumulation or to differences in organic matter decomposition and stability. These findings highlight the sensitivity of nitrogen cycling to urban land management. Crucially, the role of organic matter dynamics in this context requires deeper investigation
System-level monitoring and diagnosis of starvation faults in solid oxide electrolyzers
No full textInternational audienceThis paper presents a model-based methodology for real-time fault detection in Solid Oxide Cells (SOCs), focusing on fuel-side starvation in electrolysis mode. Steam starvation occurs when consumption exceeds supply, while hydrogen starvation arises from an insufficient inlet fraction; both risking electrode degradation. With limited measurements, a lumped model with a square-root Unscented Kalman Filter is adopted to estimate gas partial pressures, stack temperature, and deviations from the nominal inlet fuel flow rate, using stack voltage, outlet air temperature, and outlet hydrogen flow rate measurements. Faults are flagged when the estimated states exceed adaptive thresholds derived from nominal predictions via moving-window filter. For quantification, the observer is augmented with two states capturing deviations in inlet steam and hydrogen flow rates. Furthermore, the total resistance is calculated: it increases under steam starvation and remains nearly unchanged under hydrogen starvation. Experimental validation confirms accurate, real-time detection and identification, helping achieve safer SOEC operatio
Evidence for the absence of a relationship between inflammation and cognition in a cohort of 1565 individuals with bipolar spectrum disorders: a Bayesian analysis of network
No full textInternational audiencePrevious studies have reported variable associations between peripheral inflammatory markers and cognitive functioning in individuals with bipolar spectrum disorders (BSD), with some identifying significant links and others finding no relationship. Such inconsistencies raise important questions about the role of inflammation in cognitive impairment among individuals with BSD. This study aims to investigate the relationship between peripheral inflammatory markers and cognitive function in a clinical sample of individuals with BSD using a Bayesian network analysis framework. We analyzed data from a large cohort (n = 1565) focusing on hsCRP and a subsample (n = 249) that included concurrent assessments of additional cytokines including Interleukin-6 and Tumor Necrosis Factor-alpha. A Bayesian approach was utilized to quantify uncertainty regarding the presence or absence of associations between inflammation and cognitive function. Our findings revealed no significant associations between inflammatory markers and cognitive performance in both samples. Strong evidence was found supporting the absence of association, with network analysis indicating distinct clusters for cognitive and inflammatory variables, suggesting they function as independent constructs with limited interactions. In our clinical sample of individuals with BSD, our findings do not support a direct association between some inflammatory markers and cognition, aligning with studies that found minimal or no associations. Our study emphasizes the importance of utilizing Bayesian methods to assess these relationships rigorously and suggests further exploration of individual differences and subgroup effects in future research