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Magneto-: Heavy neutral lepton search using Pu decays
No full textInternational audienceWe present experimental beta spectra of Pu as part of the Magneto- experiment aimed at searching for keV heavy neutral leptons (HNLs). Total 200 million beta decays are measured by metallic magnetic calorimeters (MMCs), representing the highest statistical precision achieved for Pu to date. The end-point energy of Pu beta decay is measured via in-situ alpha calibration, yielding a value of 21.52(2) keV. The differential decay rate of the first forbidden non-unique transition of Pu is described with a quadratic shape correction factor . Using these high-statistics spectra, we set an upper limit on the admixture of a 10.5 keV sterile neutrino to the electron neutrino at for HNL mass of 10.5 keV
Bayesian Component Separation for DESI LAE Automated Spectroscopic Redshifts and Photometric Targeting
No full textInternational audienceLyman Alpha Emitters (LAEs) are valuable high-redshift cosmological probes traditionally identified using specialized narrow-band photometric surveys. In ground-based spectroscopy, it can be difficult to distinguish the sharp LAE peak from residual sky emission lines using automated methods, leading to misclassified redshifts. We present a Bayesian spectral component separation technique to automatically determine spectroscopic redshifts for LAEs while marginalizing over sky residuals. We use visually inspected spectra of LAEs obtained using the Dark Energy Spectroscopic Instrument (DESI) to create a data-driven prior and can determine redshift by jointly inferring sky residual, LAE, and residual components for each individual spectrum. We demonstrate this method on 910 spectroscopically observed DESI LAE candidate spectra and determine their redshifts with 90% accuracy when validated against visually inspected redshifts. Using the value from our pipeline as a proxy for detection confidence, we then explore potential survey design choices and implications for targeting LAEs with medium-band photometry. This method allows for scalability and accuracy in determining redshifts from DESI spectra, and the results provide recommendations for LAE targeting in anticipation of future high-redshift spectroscopic surveys
A French multicenter randomized-controlled trial of hypothermic oxygenated perfusion in extended criteria donor liver transplantation (HOPExt)
No full textInternational audienceThe aim of this study was to assess the efficacy of end-ischemic hypothermic oxygenated perfusion (HOPE) used before liver transplantation (LT) with extended criteria donor (ECD) organs from donation after brain death (DBD) in reducing early allograft dysfunction (EAD) compared with static cold storage (SCS). Between 2019 and 2023, 262 ECD-DBD grafts from 8 French centers were randomly assigned for LT either after SCS (control group, n = 131) or after SCS and subsequent 1-4 h single portal HOPE before implantation (HOPE group, n = 131). The primary endpoint was the incidence of EAD. HOPE resulted in a significantly lower rate of EAD (17.6% vs 30.5%, P = .01). Severe complication rate (61.5% vs 52.4%, P = .15), comprehensive complication index (49 [34-65] vs 46 [35-65], P = .78), and 90-day mortality (5.3% vs 2.3%, P = .20) did not differ significantly between the control and HOPE groups, respectively. Four patients (4.9%) in the control group and 3 patients (3.3%) in the HOPE group experienced ischemic cholangiopathy at 1 year after LT (P = .71). In older patients receiving grafts with more than 6 hours of cold ischemia, HOPE was associated with a lower severe complication rate (26% vs72%, P = .005). HOPE in ECD grafts from DBD for LT reduces EAD with little clinical impact on morbidity and survival in recipients with low model for end-stage liver disease scores. Older recipients with long cold ischemia time might benefit the most. Clinical trial number: NCT03929523
ESA/JUICE encounters Earth/Moon in 2024: overview of the Moons And Jupiter Imaging Spectrometer (MAJIS) observations
No full textInternational audienceAbstract. The Lunar-Earth Gravitational Assist (LEGA) of 19–20 August 2024 marked the first in-flight opportunity beyond functional checks to perform MAJIS (Moons and Jupiter Imaging Spectrometer) observations on-board the ESA's Jupiter Icy Moons Explorer (JUICE) spacecraft. This unique double flyby involved sequential close approaches to the Moon and Earth, offering an unprecedented configuration to evaluate MAJIS under high radiance, rapidly changing geometric, and operationally constrained conditions. A total of 24 hyperspectral image cubes were acquired (5 targeting the Moon and 19 the Earth) providing a dataset of approximately 7.5 Gbit. This work presents the primary goal of this observation campaign, which was to verify key aspects of MAJIS performance, including radiometric and spectral calibration, straylight behavior, geometric alignment, the use of onboard browse products, and interference tests with other JUICE instruments. This event also enabled assessment of thermal behavior and susceptibility to electromagnetic interference, and provided a first operational benchmark for MAJIS and a basis for refining future observation strategies and data analyses during JUICE's cruise and science phases. In addition, despite limited spatial and temporal coverage of the observations, the analyses presented here and in a series of companion papers of the special issue “The first-ever lunar-Earth flyby: a unique test environment for JUICE” demonstrated the instrument's ability to characterize mineralogical features on the Moon and atmospheric constituents on Earth. Observations include detection of mafic minerals (some associated to fresh excavated materials), thermal emission, and emissivity variations on the Moon at spatial scale of 100–200 m. Characterization of atmospheric absorption features, thermal brightness, icy cloud properties are captured for the Earth at km-scale and briefly discussed in the framework of the atmospheric biosignatures relevant to exoplanet habitability studies. Near-coincident acquisitions with other JUICE instruments and Earth-orbiting spectrometers provided valuable inter-calibration and cross-validation opportunities
Irradiation-resistant heterostructures based on monolayer MoS 2
No full textInternational audienceMonolayer molybdenum disulfide is a semiconducting 2D material presenting very appealing characteristics for its incorporation into electronic flexible devices. At present, atomic vacancies in its structure are known to significantly affect its properties. Nonetheless, the effects of electron irradiation on it are still under investigation. In this work, the structural, electronic, and optical properties of monolayer molybdenum disulfide are studied before and after electron irradiation. By analyzing samples either obtained via a mechanical exfoliation process or grown via chemical vapor deposition, we show that following irradiation no significant change is present. This result indicates a strong resistance to the effect of electron irradiation at energies able to induce the formation of sulfur vacancies. By comparing our results to the current literature, we hypothesize that previously reported effects of electron irradiation are either due to the formation of molybdenum vacancies or to ionization of the electronic shell of this material. The presented results help to shed light on the role of atomic vacancies on the properties of this 2D material from a fundamental point of view and on its usage in extreme environment applications
Cognitive impairment predicts adverse outcomes in chronic kidney disease
No full textInternational audienceBackgroundCognitive impairment (CI) affects self-management in chronic diseases, leading to poor decision-making, delayed care, and increased mortality. The specific impact of CI on adverse outcomes in CKD remains poorly explored.MethodsThe french CKD-REIN cohort included 3033 patients with CKD stage 2–5 and 5 years of follow-up. CI was assessed using the Mini-Mental State Examination (MMSE), and eGFR was estimated with the CKD-EPI creatinine equation. Cox models evaluated the risks of all-cause mortality, kidney replacement therapy (KRT) initiation, and major adverse cardiovascular (CV) events (MACEs).Results3004 patients were included in the analysis (mean age: 67 years, mean eGFR 34 mL/min/1.73 m2), and 64%, 23% and 13% respectively had MMSE scores of >26, between 24-26, and 26: HR [95% confidence interval] was 1.42 [1.12, 1.81], 1.57 [1.19, 2.07], and 1.32 [1.02, 1.70] for KRT initiation, all-cause mortality and MACE respectively. CI was associated with all-cause mortality in the MMSE 24-26 group also (HR: 1.45 [1.15, 1.83]).ConclusionIn CKD, a baseline MMSE score 26. These results highlight CI’s prognostic value, and suggest that earlier detection could better personalize management, particularly for kidney and CV complications
A benchmark of expert-level academic questions to assess AI capabilities
No full textInternational audienceBenchmarks are important tools for tracking the rapid advancements in large language model (LLM) capabilities. However, benchmarks are not keeping pace in difficulty: LLMs now achieve more than 90% accuracy on popular benchmarks such as Measuring Massive Multitask Language Understanding1, limiting informed measurement of state-of-the-art LLM capabilities. Here, in response, we introduce Humanity’s Last Exam (HLE), a multi-modal benchmark at the frontier of human knowledge, designed to be an expert-level closed-ended academic benchmark with broad subject coverage. HLE consists of 2,500 questions across dozens of subjects, including mathematics, humanities and the natural sciences. HLE is developed globally by subject-matter experts and consists of multiple-choice and short-answer questions suitable for automated grading. Each question has a known solution that is unambiguous and easily verifiable but cannot be quickly answered by internet retrieval. State-of-the-art LLMs demonstrate low accuracy and calibration on HLE, highlighting a marked gap between current LLM capabilities and the expert human frontier on closed-ended academic questions. To inform research and policymaking upon a clear understanding of model capabilities, we publicly release HLE at https://lastexam.ai
The experience of professionals receiving patients with manifestations of traumatic dissociation: a qualitative study
No full textInternational audienceBackground: Traumatic dissociation is defined as a disruption or disturbance in the integration of various cognitive functions in response to a traumatic event and has been the subject of extensive research in recent decades. For mental health professionals, exposure to patients with a history of trauma can have both negative and positive effects on their well-being. However, few studies have focused on the specific experiences of professionals encountering patients with traumatic dissociation.Method: This study analyzed the experiences of 23 professionals (psychiatrists, psychologists, and residents in psychiatry) working with patients presenting manifestations of traumatic dissociation, using Interpretative Phenomenological Analysis (IPA) methodology.Results: This approach led to the identification of three key themes: (1) professionals' reactions to patient dissociation, (2) professionals' emotional and dissociative response, and (3) factors influencing reactions and impact on professionals' life.Conclusion: In light of these findings, we propose several key points for training and supervision: taking into account the question of the body and physical contact; addressing the emotions experienced by professionals, particularly helplessness and loneliness, and carefully utilizing the diffusion of emotions and dissociation from the patient to the professional as a therapeutic tool to help patients self-regulate and reintegrate dissociated parts of themselves
Combined methotrexate and short-term superpotent topical corticosteroids compared with prolonged superpotent topical corticosteroids alone in bullous pemphigoid: a multicentre, noninferiority randomised clinical trial
No full textInternational audienceBackground Superpotent topical corticosteroids (STS) are highly effective in bullous pemphigoid (BP), but prolonged use is associated with practical limitations and a risk of relapse. Objective To evaluate whether combining short-term STS with methotrexate (MTX) could maintain efficacy, reduce relapses, and preserve safety compared with prolonged STS alone. Methods In this multicentre, randomised, open-label, non-inferiority trial, adults with BP were assigned to receive either STS (clobetasol propionate) for one month plus low-dose MTX as maintenance (MTX + STS arm), or prolonged STS alone (STS arm). The primary endpoint was 9-month overall survival (OS), with a predefined non-inferiority margin of 15%. Secondary outcomes included relapse-free survival (RFS) and severe adverse events (SAE). Results Among 266 randomised patients (mean age 80.8 years), 9-month OS was 86.5% in the MTX + STS arm and 83.5% in the STS arm (p=0.498; hazard ratio [HR] 0.80, 95% CI 0.40–1.50). The lower limit of the 90% confidence interval for the difference in survival rates (−4.6%) remained within the predefined non-inferiority margin, meeting the primary endpoint. Among the 87.4% of patients who achieved disease control within 28 days, relapse occurred in 31 patients in the MTX + STS arm and 52 in the STS arm, corresponding to a 9-month RFS of 68.4% (95% CI 59.3–78.8) versus 47.4% (95% CI 37.7–59.5), respectively (p=0.042). SAE were more frequent in the MTX + STS arm than in the STS arm (mean number per patient per month 0.40 [95% CI 0.23–0.57] vs 0.19 [95% CI 0.01–0.36], p=0.005). Limitations The study was open-label, did not include a validated disease activity score and was conducted in a selected BP population managed under clinical trial conditions. Conclusion Maintenance therapy with low-dose MTX is non-inferior to prolonged STS in terms of survival and is associated with a reduced risk of relapse, at the cost of increased toxicit
From German Mines to Le Nôtre's Gardens: The Origin of the Lead in the Fountains of Vaux‐le‐Vicomte and Versailles (Île‐de‐France, France)
No full textInternational audienceThis article presents the results of an isotopic study of the lead used in the fountains of the gardens at the palaces of Versailles and Vaux‐le‐Vicomte—two iconic examples of French formal gardens designed by André Le Nôtre. The construction of these monumental gardens in the 17th century required considerable quantities of lead, a material not found in the subsoil of the Paris region and therefore necessarily imported. Lead Isotope analysis of 16 samples (including pipes, solder joints and basin plates) reveals a homogeneous signature, indicating a shared supply source for both sites. Comparing these results with those from different European mining districts revealed a clear correspondence with the deposits in the Harz Mountains in Germany, which were active and important in the 17th century. However, a few samples associated with later construction phases suggest that additional supplies came from other deposits, probably located in France. These results highlight not only the importance of European trade networks in the supply of construction materials but also the geopolitical dimension of these choices, as Louis XIV's France sought to produce lead in order to substitute it for that obtained through costly imports