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Euclid preparation. Impact of galaxy intrinsic alignment modelling choices on Euclid 3x2pt cosmology
No full textInternational audienceThe Euclid galaxy survey will provide unprecedented constraints on cosmology, but achieving unbiased results will require an optimal characterisation and mitigation of systematic effects. Among these, the intrinsic alignments (IA) of galaxies are one of the dominant contaminants of the weak lensing (WL) and galaxy-galaxy lensing (GGL) probes. In this work, we assess IA modelling choices for Euclid DR1 3x2pt analyses by comparing the performance of the two most commonly used IA models, nonlinear alignment (NLA) and tidal alignment tidal torquing (TATT), along with several variations. Our analyses combine three perspectives: i) the constraining power on the IA and cosmological parameters for each IA model, ii) the bias that results when the IA analysis model differs from the model used to generate the synthetic data vector, and iii) the degeneracies between IA and photometric redshift (photo-z) nuisance parameters. Among the IA models analysed, the redshift-dependent TATT model (zTATT) provides the most flexible description of IA, with a similar constraining power compared to simpler IA models, making it a well-motivated choice for Euclid DR1 3x2pt analyses
Saturation of superconductivity in cuprates overdoped with high-pressure oxygen: Phase diagram with YBa2Cu3O7+δ, δ → 1
No full textInternational audienceHigh temperature superconductivity (HTSC) typically occurs as a “dome” over a narrow range of doping in its phase diagram. The reaction of YBa2Cu3O7 with Ag2O2 at T≥800 °C and 6 GPa inserts oxygen atoms between the Cu1 sites to form tetragonal YBa2Cu3O8 without significant changes to its overall structure or interatomic distances. The superconductivity in YBa2Cu3O8 is essentially unaffected, with the reduction of the transition temperature by ≤2 K and its superconducting fraction by ≤ 15% between the O7 and O8 endpoints of the oxygen stoichiometry and associated carrier density. The dome therefore only pertains to compounds doped by cation substitution or presumably interstitial oxygen. Band structure calculations of the fully ordered endpoints show substantial changes in the density of states at the Fermi level because of its shift to lower energy with increasing oxygen stoichiometry. The coincidence of optimum and saturation HTSC at a carrier:CuO 2 ratio of ≈1/6 implies a direct coupling of HTSC with the lattice such that this value is intrinsic to the superconducting phase. The SC in YBa2Cu3O8 is therefore not only pinned at its optimum values but also separated from the other electronic states so that the additional holes have no measurable effect on the condensate. In addition, the 95 K transition temperature of Sr2CuO3.4 that possesses CuO 1.5 ladders instead of CuO2 planes reveals a second distinct behavior of cuprates overdoped with high-pressure oxygen, demonstrating significant gaps in our understanding of HTSC
Inclusive production at midrapidity in pp collisions at TeV
No full textInternational audienceInclusive production of mesons is measured for the first time at midrapidity () in pp collisions at TeV using the ALICE detector at the LHC. The measurement is performed in the transverse-momentum () range of 4 to 16 GeV/ and is based on events triggered by the Transition Radiation Detector, corresponding to an integrated luminosity of (syst.) pb. The -differential production cross section of the and its ratio to the J/ production cross section are presented. The results extend the accessible range down to 4 GeV/, and a mild rise of the -to-J/ cross section ratio with increasing is observed. The measurements are compared with theoretical predictions based on NRQCD and the ICEM model
Polarization measurement of and baryons in Ne collisions at GeV
No full textInternational audienceThe first measurement of the polarization of charm baryons by the LHCb experiment recorded in fixed-target mode is presented. The polarization of baryons is studied in collisions of protons, at an energy of 2.51 TeV, incident on a gaseous target of neon, at a nucleon-nucleon center-of-mass energy of GeV. The world's first measurement of separate-charge polarizations for and baryons is performed, determining where the first uncertainty is statistical and the second systematic. The polarization is also measured in intervals of baryon transverse momentum and the Feynman- variable
Symmetry-Induced Logarithmic Relaxation in the Quantum Kicked Rotor
No full textWe study the effect of discrete symmetries on coherent multiple scattering in the quantum kicked rotor. When the initial momentum is set to zero -- as in recent Bose-Einstein condensate experiments -- the effective pseudo-disorder becomes even under momentum inversion. The resulting discrete mirror symmetry of the dynamics profoundly alters spectral correlations: it generates quasi-degenerate Floquet doublets localised at opposite momenta, whose exponentially small splittings produce a hierarchy of exponentially large dynamical timescales. The coherent backscattering and forward-scattering peaks then exhibit a striking non-monotonic evolution and strongly asymmetric contrasts, followed by an exceptionally slow logarithmic relaxation toward a common asymptotic value -- a hallmark of glassy dynamics, here emerging in a fully coherent quantum system. That such archetypal glass-like behaviour arises from a single discrete symmetry constraint reveals an unexpected and deep connection between quantum coherence and slow relaxation phenomena
Association between GP characteristics and prescription patterns for antihypertensive drugs: a secondary data analysis in Normandy, France
No full textInternational audienceBackgroundEssential hypertension incurs substantial cardiovascular morbidity and mortality, particularly in primary prevention settings. General practitioners (GPs) play a pivotal role in the management of uncomplicated hypertension in primary care, yet variations exist among GPs. The determinants shaping GPs’ antihypertensive drugs (AD) prescription patterns in the setting of hypertension remain ambiguous.ObjectivesThis investigation sought to examine the correlation between GP characteristics and professional activities on the prescribing patterns of ADs within the context of uncomplicated hypertension management.MethodsA secondary data analysis utilizing a sample of 2,165 GPs was conducted in Normandy, France, in 2019. The ratio of AD prescriptions to overall prescription volume was computed for each GP. GPs were classified as ‘low’ or ‘high’ AD prescribers based on the median of this ratio. The ratio was examined in relation to GPs’ demographic and professional variables such as age, gender, practice setting, years of experience, consultation frequency, the demographics and socioeconomic status of their patient panels, and prevalence of chronic conditions in patients. These associations were explored using both univariate and multivariate analyses.ResultsGPs categorized as low prescribers had a mean age of 51.3 ± 11.2 years and were predominantly female (56%). In multivariate logistic regression, low-prescriber status correlated with urban practice location (OR: 1.47, 95% CI: 1.14–1.88), younger GP age (OR: 1.87, 95% CI: 1.42–2.44), younger patient population (OR: 3.39, 95% CI: 2.77–4.15), higher consultation rate per patient (OR: 1.33, 95% CI: 1.11–1.61), greater proportion of low-income patients (OR: 1.44, 95% CI: 1.17–1.76), and a lower prevalence of diabetes mellitus (OR: 0.72, 95% CI: 0.59–0.88) throughout 2019.ConclusionLow AD prescription rates are associated with younger, urban-based GPs who experienced higher patient consultation rates in 2019 and managed populations with lower income profiles.Clinical ImplicationsThe prescription of antihypertensive medications might be significantly influenced by GPs' professional attributes and activities within the French healthcare setting
Recent advancements in human-centric entertainment AI: challenges and benefits
No full textInternational audiencePurpose This paper aims to review and analyze recent advancements in human-centric artificial intelligence (AI) systems designed for interactive entertainment environments. It emphasizes how AI technologies are reshaping human–machine interaction (HMI), enabling adaptive, personalized and immersive experiences for users across entertainment modalities. Design/methodology/approach The authors conduct a systematic review of AI applications across a wide range of entertainment types, including role-playing, simulation, strategy and sandbox environments. The study categorizes technical advances in procedural content generation, player modeling, reinforcement learning and natural language processing. Special attention is given to interaction paradigms such as user-agent collaboration, multimodal inputs, affective computing and co-creative interfaces. The methodology further analyzes how these components contribute to meaningful and dynamic HMI design. Findings AI technologies in entertainment are moving beyond rule-based systems toward context-aware, behavior-driven architectures. These systems enable emotionally responsive, adaptively personalized and cognitively rich interaction loops. However, challenges remain in explainability, transparency, data ethics and the transferability of user models across entertainment domains. Originality/value This paper bridges the gap between AI innovation and interactive entertainment design by reframing entertainment AI through the lens of HMI. It identifies key benefits such as increased engagement and creative empowerment, while also proposing a future-oriented roadmap to address technological and ethical challenges in deploying human-centered AI systems for entertainment
Le numérique frugal au service de la décarbonation
No full textParole d’experts : Groupe de Travail "Décarbonation & Numérique Frugal" de Systematichttps://systematic-paris-region.org/parole-dexperts-le-numerique-frugal-au-service-de-la-decarbonation-chapitre-5-lindispensable/Chapitre 5 : L’indispensable Stimuler et soutenir le développement des solutions logiciellesLien vers l'article (version web)Lien vers l'article (version pdf)</a
Une coordination territoriale des soins : Actes du séminaire de la Chaire santé 2024
No full textInternational audienceLa Chaire Santé de Sciences Po a organisé en 2024 un séminaire consacré à la coordination et à la territorialisation des soins. Ces actes en constituent la synthèse : ils restituent les travaux présentés et les discussions auxquelles ce séminaire a donné lieu. Les contributions réunies interrogent les recompositions en cours du système de santé, dans ses efforts pour coordonner les soins, les parcours et les secteurs d'intervention. Elles abordent notamment le travail des infirmières libérales, des Centres de Lutte contre le Cancer et des Communautés Professionnelles Territoriales de Santé, ainsi que le rôle des élus, des collectivités territoriales et des administrations sanitaires (ARS, CPAM) dans ces dynamiques.Ce basculement territorial, qui promeut des innovations locales pour améliorer l'accès aux soins, est traversé de profondes tensions. D'un côté, il vise à renforcer la coordination des soins et des secteurs d'intervention, ainsi que le maillage des services de santé à l'échelle des territoires. De l'autre, il procède d'une planification nationale du déploiement de cette coordination, dans un contexte de raréfaction des ressources médicales et de maîtrise des dépenses de santé. Le livret examine les effets de ce paradoxe sur les pratiques professionnelles et sur les relations qui se nouent entre acteurs locaux, élus et institutions sanitaires. Il revient sur un basculement qui tend à faire de la santé un objet d'intervention à la fois territorial et national, au coeur des transformations de l'État social contemporain
Long-term MAPK inhibition of childhood refractory-Langerhans cell histiocytosis: an observational study on 288 patients
No full textInternational audienceWe evaluated long-term outcomes of 288 children with refractory-Langerhans cell histiocytosis (R-LCH) from 26 countries prescribed off-label mitogen-activated protein kinase inhibitors (MAPKis) according to clinical indications. MAPKi indications were: 148 R-risk-organ-positive (R-RO+), 67 R-RO-negative (R-RO-), 13 lung destruction (lung), 9 sclerosing cholangitis (SC), 49 neurodegeneration (ND) and 2 diabetes insipidus (DI). Median ages at diagnosis and MAPKi onset were 1.3 and 2.3 years, respectively, with median follow-up of 3.7 years (1166 person-years). Agents were mostly prescribed as monotherapies: 184 vemurafenib, 115 dabrafenib, 3 encorafenib, 42 cobimetinib, 45 trametinib and/or 1 binimetinib; followed 51 times by various chemotherapies or hematopoietic stem-cell transplantation, or combined anti-BRAF-anti-MEK 28 times. Short-term responses (&lt;8 weeks) ranged from 98% (R-RO+ and R-RO-), to 30% (lung) to none (ND, DI and SC), although long-term lung and ND responses could be observed. Skin rash was the most frequent adverse event (~55%); 7 others were 1 cardiomyopathy and 6 retinitis. Five developed MAPKi-unrelated tumors. Nine patients died. Five-year survival was 98%. After 113 patients with R-LCH discontinued MAPKi, 69 experienced disease reactivation. None of the various empirical maintenance therapies were able to prevent secondary reactivation. Among the 143 assessable patients without ND-LCH at MAPKi onset, 60 developed ND: 45% 5-year risk. MAPKis appeared to be safe and effective in children with R-RO+/RO-LCH, while other indications' responses were less frequent or occurred later. Further studies are needed to find effective maintenance-therapy approaches, particularly to prevent frequently observed secondary ND