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Analytic symplectomorphisms displaying minimal ergodicity on the sphere, cylinder and disk
No full textWe construct analytic symplectomorphisms on the sphere, the disk and the cylinder which are minimally ergodic (only 3 ergodic measures). To achieve this, we apply and generalize a principle introduced by Berger, based on the Approximation by Conjugacy method of Anosov-Katok
Lifshitz critical points meet Zamolodchikov perturbation theory
No full textInternational audienceCritical points of classical and quantum lattice models are often described by scale-invariant Lifshitz theories which are anisotropic in the continuum limit, as characterized by a dynamical critical exponent . This type of critical behavior can in principle be studied by deforming ordinary conformal field theories (CFTs) by relevant vector operators breaking the rotational/Lorentz symmetry. In this short note, we consider a two-dimensional system of coupled minimal model CFTs which realizes this perspective in a controlled fashion via Zamolodchikov's large expansion. The model turns out to exhibit interesting properties, including a manifold of interacting Lifshitz fixed points and emergent rotational symmetry in the infrared
Du détournement au retournement : la vulnérabilité comme ressort de domination en Équateur
No full textInternational audienceAls zentraler Begriff der Risikoanalyse hat die Vulnerabilität ihren Ursprung in den radikalen englischsprachigen Strömungen der 1970er Jahre. Lateinamerika hat dessen kritische Stoßrichtung durch die Einführung der Perspektive der (Fehl-)Entwicklung (maldéveloppement) und transformativer Perspektiven gestärkt. Die Analyse der Entwicklung der Vulnerabilität in Ecuador (insbesondere in den Städten Quito und Esmeraldas) seit Beginn der 2000er Jahre zeigt, dass die breite Verbreitung des Begriffs mit einer Abkehr von seiner kritischen Bedeutung einhergeht. Sie zeugt sogar davon, dass der Begriff in seiner Verwendung umgekehrt wurde und als Motor der sozialen Ordnung zum Vorteil des Status quo, als mächtige Technopolitik, mobilisiert wird. Angesichts dieses doppelten Prozesses der Umdeutung liegt es im Interesse der Sozialwissenschaften, den Politikwandel rund um diesen Begriff zu verdeutlichen, um seine Verwendung nicht den Herrschenden zu überlassenA key concept in risk analysis, vulnerability is rooted in the radical English-speaking currents of the 1970s. Latin America helped to establish its critical nature by introducing the perspective of (mal)development and transformative horizons. An analysis of the trajectory of vulnerability in Ecuador (in particular, the cases of Quito and Esmeraldas) since the early 2000s shows that the widespread dissemination of the notion has gone hand in hand with the hijacking of its critical charge. It even testifies to the fact that the notion is being turned on its head, mobilized as a critical lever for social order in favor of the status quo, as a powerful techno-political tool. Faced with this dual process of hijacking and reversal mechanism, the social sciences have an interest in clarifying the political transformations at work around the notion, so as not to abandon its use to the dominant.Concepto clave en el análisis de riesgos, la vulnerabilidad se origina en los movimientos radicales anglófonos de los años setenta. América Latina contribuyó a establecer su carácter crítico al introducir la perspectiva del (mal)desarrollo y considerar horizontes transformadores. Un análisis de la trayectoria de la vulnerabilidad en Ecuador (en particular los casos de Quito y Esmeraldas) desde inicios de la década del 2000 muestra que la amplia difusión del concepto ha ido de la mano con el desvío de su carga crítica. Incluso muestra que el concepto va en sentido contrario, movilizado como un mecanismo de reproducción del orden social, como una poderosa herramienta tecno-política. Frente a este doble proceso de desvío/rumbo contrario, las ciencias sociales tienen interés en esclarecer las recomposiciones políticas en curso en torno a la noción, para no abandonar su uso a las fuerzas dominantes.Notion phare de l’analyse des risques, la vulnérabilité est ancrée dans les courants radicaux anglophones des années 1970. L’Amérique latine a contribué à asseoir son caractère critique en introduisant la perspective du (mal)développement et d’horizons transformateurs. L’analyse de la trajectoire de la vulnérabilité en Équateur (notamment les cas des villes de Quito et Esmeraldas) depuis le début des années 2000 montre que la diffusion large de la notion est concomitante du détournement de sa charge critique. Elle témoigne même du fait que la notion est retournée dans son usage, mobilisée comme ressort de l’ordre social au bénéfice du statu quo, comme une techno-politique puissante. Face à ce double processus de détournement/retournement, les sciences sociales ont intérêt à expliciter les recompositions à l’œuvre du politique autour de la notion pour ne pas en abandonner l’usage aux dominants
In silico prediction of the lipid-lowering efficacy of the oral PCSK9 inhibitor enlicitide using a mechanistic computational model
No full textInternational audienceBackground and aims: Regulatory agencies increasingly support model-informed drug development, including quantitative systems pharmacology (QSP) models, but confidence in model-based predictions for decision making remains limited. We previously developed a mechanistic QSP model of atherosclerosis to simulate LDL-C responses to lipid-lowering therapies, which was extensively calibrated and retrospectively validated using published data from prior clinical trials. The recent completion of two phase 3 trials of the oral PCSK9 inhibitor enlicitide decanoate, CORALreef Lipids (NCT05952856) and CORALreef AddOn (NCT06450366), provided an opportunity for prospective validation, the highest standard for establishing predictive credibility.Methods: The model was recalibrated using phase 1 PK/PD data and phase 2b LDL-C response data to incorporate enlicitide's effect. Predictions for both trials were generated and publicly posted, independently of the sponsor and prior to any data release.Results: For CORALreef Lipids, the predicted week-24 LDL-C reduction was -54.5% (95% PPI: -56.1%, -53.0%), closely matching the subsequently reported -55.8% (95% CI: -60.9%, -50.7%). For CORALreef AddOn, predicted week-8 LDL-C reductions were -59.4% (95% PPI: -65.7, -53.4) with enlicitide, -18.0% (-20.1, -15.8) with bempedoic acid, -24.6% (-26.6, -22.7) with ezetimibe, and -39.8% (-42.8, -36.9) with their combination; comparison with actual trial outcomes is pending trial readout.Conclusions: This first successful prospective validation of our mechanistic QSP model against a large cardiovascular phase 3 trial, confirms the model's credibility. It supports the contribution of in silico trials to accelerate the development and evaluation of innovative lipid-lowering therapies to improve cardiovascular outcomes
Prenatal and early intimate partner psychological violence and children’s hospital healthcare use: the ELFE cohort
No full textInternational audienc
Low-dimensional representation of brain networks for seizure risk forecasting
No full textIdentifying preictal states -- periods during which seizures are more likely to occur -- remains a central challenge in clinical computational neuroscience. In this study, we introduce a novel framework that embeds functional brain connectivity networks, derived from intracranial EEG (iEEG) recordings, into a low-dimensional Euclidean space. This compact representation captures essential topological features of brain dynamics and facilitates the detection of subtle connectivity changes preceding seizures. Using standard machine learning techniques, we define a dimensionless biomarker, , that discriminates between interictal (seizure-free) and preictal (within 24 hours of seizure) network states. Our method focuses on connectivity patterns among a subset of informative iEEG electrodes, enabling robust classification of brain states across time. We validate our approach using a leave-one-out cross-validation scheme and a pseudo-prospective forecasting strategy, assessing performance with metrics such as F1-score and balanced accuracy. Results show that low-dimensional Euclidean embeddings of iEEG connectivity yield interpretable and predictive markers of preictal activity, offering promising implications for real-time seizure forecasting and individualized therapeutic interventions
Stoichiometry-driven tuning of hole conductivity in MOCVD-grown β-Ga2O3 on r-sapphire substrates
No full textInternational audienceβ-Ga2O3 is a promising ultra-wide bandgap semiconductor for next-generation power and optoelectronic devices, but achieving stable p-type conductivity remains a major challenge with limited understanding of native point defects engineering. In this work, we report a systematic study on the influence of Ga and O flow rate during MOCVD growth on the structural and electrical properties of undoped β-Ga2O3 epilayers. Two sets of samples were grown: (i) varying oxygen content to span O/Ga ≈ 180-2700 at fixed Ga content, and (ii) varying gallium content at fixed O/Ga = 1600.Structural characterization using out-of-plane and in-plane high resolution X-ray diffraction, Raman spectroscopy, and scanning electron microscopy revealed a strong correlation between growth conditions and film microstructure. Increasing O/Ga flow ratio improves grain alignment, reduces lattice disorder. Hall effect measurements show the semi-insulating p-type conductivity in all samples, with enhancement of native p-type conductivity in oxygen-rich conditions, increasing the hole concentration from 6.0×10 13 to 1.7×10 15 cm -3 at 800 K. Interestingly, the improvement in hole mobility correlates with the increasing in Ga content (up to 18.5 cm 2 /V•s) at higher growth rate and improved grain alignment. These results demonstrate that reproducible control of stoichiometry and microstructure of β-Ga2O3 thin films grown by MOCVD provides a possibility to tune native-defect concentrations, thus electrical properties of material
Une étude nationale des personnes décédées par suicide dans les prisons françaises sur la période 2017-2021
No full textInternational audienceObjective: Suicide is a leading cause of death in prisons worldwide. The objective of this study was to describe the sociodemographic, clinical and criminal characteristics of people incarcerated in France who died by suicide, as well as the circumstances surrounding each suicide.Method: We included all cases of suicide by people incarcerated in France (i.e., European and overseas territories) over the period 2017-2021. The National Prison Service provided sociodemographic and criminal data, as well as data on the circumstances surrounding the suicides. Health data were collected by health units located in all the country's prisons using a standardised questionnaire.Results: We included 598 suicide cases in the study. Mental disorders were more prevalent during (63.7%) than before (47.8%, p<0.001) incarceration. In the week before suicide, 60% of cases had visited their prison's health unit and a traumatic criminal-, prison-, familial-or health-related event was identified in 61% of all cases. Persons who died during the SARS-CoV2 pandemic were more likely to have children (77.7% vs 61.1%, p=0.001). The overall suicide rate was 17.5 [CI 95% 16.1-18.9] per 10,000 person-years. It increased (p<0.05) with age, was twice as high during pre-trial incarceration and six times higher during the first week of imprisonment. In terms of gender, it was 9.9 [9.1-10.7] and 41.0 [27.0-59.7] times higher among men and women, respectively, than among their counterparts in the general population.Conclusions: Suicide in prisons is a major health issue. Suicide prevention measures must be reinforced.Objectif : Le suicide est l'une des principales causes de décès dans les prisons à travers le monde. L'objectif de cette étude était de décrire les caractéristiques sociodémographiques, cliniques et pénales des personnes incarcérées en France qui sont décédées par suicide, ainsi que les circonstances entourant le suicide. Méthode : Nous avons inclus tous les cas de suicide de personnes incarcérées en France (c'est-à-dire en métropole et dans les territoires d'outre-mer) au cours de la période 2017-2021. L'administration pénitentiaire nationale a fourni des données sociodémographiques et pénales, ainsi que des données sur les circonstances entourant les suicides. Les données sanitaires ont été recueillies par les unités sanitaires situées dans toutes les prisons du pays à l'aide d'un questionnaire standardisé. Résultats : Nous avons inclus 598 cas de suicide dans l'étude. Les troubles mentaux étaient plus fréquents pendant (63,7 %) qu'avant (47,8 %, p<0,001) l'incarcération. Au cours de la semaine précédant le suicide, 60 % des personnes s'étaient rendus au service de santé de leur prison et un événement traumatisant lié à la criminalité, à la prison, à la famille ou à la santé a été identifié dans 61 % des cas. Les personnes décédées pendant la pandémie de SARS-CoV2 étaient plus susceptibles d'avoir des enfants (77,7 % contre 61,1 %, p=0,001). Le taux global de suicide était de 17,5 [IC 95 % 16,1-18,9] pour 10 000 personnes-années. Il augmentait (p<0,05) avec l'âge, était deux fois plus élevé pendant la détention provisoire et six fois plus élevé pendant la première semaine d'incarcération. Il était respectivement 9,9 [9,1-10,7] plus élevé chez les hommes et 41,0 [27,0-59,7] fois plus élevé chez l les femmes que chez leurs homologues en population générale.Conclusion : Les suicides des personnes détenues est un enjeu de santé publique majeur. Les mesures de prévention du suicide doivent être renforcées
Validation of EarthCARE CPR reflectivity using the ACTRIS cloud radar network
No full textInternational audienceThe Earth Cloud, Aerosol, and Radiation Explorer (EarthCARE) satellite carries a cloud profiling radar (CPR) designed to observe global cloud properties. In this study, we assess the calibration of CPR reflectivity profiles by comparing them with seven calibrated ground-based cloud radars from the European Aerosol, Clouds and Trace Gases Research Infrastructure (ACTRIS).We compare the statistics of ice cloud reflectivities observed from space and from each ground site. The CPR dataset includes all observations within a 200 km radius of each site, while the ground-based dataset comprises vertical profiles collected during the same time period. By analysing the differences in reflectivity statistics, we estimate the calibration bias between CPR and each site. To ensure robustness, we implement a method to select height bins with comparable reflectivity statistics, excluding uncorrelated observations that could contaminate the results. The reliability of our bias estimates is validated through closure: each ground radar has been calibrated using the same reference, and the independently derived space-versus-ground biases obtained across sites are consistent. Our methodology also provides uncertainty estimates for the reflectivity biases and explores the time sampling required for reliable comparisons.Based on the comparisons from the seven ground-sites, we find that the bias in the EarthCARE L2a reflectivity product is of -0.2 ± 0.4 dB, confirming the high quality of the satellite's calibration. This robust statistical approach, validated with calibrated radars, establishes EarthCARE as a potential reference for calibrating ACTRIS and other ground-based sites in the future