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ReMi: A Random Recurrent Neural Network Approach to Music Production
No full textInternational audienceGenerative artificial intelligence raises concerns related to energy consumption, copyright infringement and creative atrophy. We show that randomly initialized recurrent neural networks can produce arpeggios and low-frequency oscillations that are rich and configurable. In contrast to end-to-end music generation that aims to replace musicians, our approach expands their creativity while requiring no data and much less computational power. More information can be found at: https://allendia.co
Molecular distinction of cell wall and capsular polysaccharides in encapsulated pathogens by in situ magic-angle spinning NMR techniques
No full textInternational audiencePathogenic fungal and bacterial cells are enveloped within a cell wall, a molecular barrier at their cell surface, and a critical architecture that constantly evolves during pathogenesis. Understanding the molecular composition, structural organization, and mobility of polysaccharides constituting this cell envelope is crucial to correlate cell wall organization with its role in pathogenicity and to identify potential antifungal targets. For the fungal pathogen Cryptococcus neoformans, the characterization of the cell envelope has been complexified by the presence of an additional external polysaccharide capsular shell. Here, we investigate how magic-angle spinning (MAS) solid-state NMR techniques increase the analytical capabilities to characterize the structure and dynamics of this encapsulated pathogen. The versatility of proton detection experiments, dynamic-based filters, and relaxation measurements facilitate the discrimination of the highly mobile external capsular structure from the internal rigid cell wall of C. neoformans. In addition, we report the in situ detection of triglyceride molecules from lipid droplets based on NMR dynamic filters. Together, we demonstrate a nondestructive technique to study the cell wall architecture of encapsulated microbes using C. neoformans as a model, an airborne opportunistic fungal pathogen that infects mainly immunocompromised but also competent hosts
Hourly physicochemical parameters measured underwater on oyster tables during a one-year semi-controlled experiment
No full textdatasetThis dataset shows the hourly physicochemical parameters measured underwater throughout the year of the experiment. The temperature and water depth were measured on each oyster table (control and ALAN conditions, at the oyster's level), while the turbidity was measured only on the ALAN table, and conductivity and salinity were measured only on the control table
Hourly valve opening data of oysters Crassostrea gigas measured during a one-year semi-controlled experiment
No full textdatasetThis dataset shows the hourly valve behavioral data of the 32 oysters Crassostrea gigas throughout the year of the experiment as well as the temperature recorded by each HFNI valvometer. The oyster valve behavior is characterized by 3 parameters: the Valve Opening Amplitude (VOA, the percentage of the valve opening relative to maximum opening), the Valve Opening Duration (VOD, the percentage of time that an oyster spends with its valves open), and the VOA/VOD. For each parameter, the data are presented for each oyster and as a group average for each condition. Missing data correspond to the death of oysters or the stopping of recording by a HFNI valvometer
On the Computation of Schrijver's Kernels
No full textarticle scientifiqueThe geometry of a graph embedded on a closed oriented surface can be probed by counting the intersections of with closed curves on . Of special interest is the map counting the minimum number of intersections between and any curve freely homotopic to a given curve . Schrijver [On the uniqueness of kernels, 1992] calls a kernel if for any proper graph minor of we have μ_H < μ_G. Hence, admits a minor which is a kernel and such that . We show how to compute such a minor kernel of in time where is the number of edges of , and is the genus of . Our algorithm leverages a tight bound on the size of minimal bigons in a system of closed curves. It also relies on several subroutines of independent interest including the computation of the area enclosed by a curve and a test of simplicity for the lift of a curve in the universal covering of . As a consequence of our minor kernel algorithm and a recent result of Dubois [Making multicurves cross minimally on surfaces, 2024], after a preprocessing that takes time and space, we are able to compute in time given any closed walk with edges. The state-of-the-art algorithm by Colin de Verdière and Erickson [Tightening non-simple paths and cycles on surfaces, 2010] would avoid constructing a kernel but would lead to a computation of in time (with a preprocessing that takes time and space). Another consequence of the computation of minor kernels is the ability to decide in polynomial time whether two graph minors and of satisfy
Existence of solutions and uniform bounds for the stationary semiconductor equations with generation and ionic carriers
No full textWe consider a stationary drift-diffusion system with ionic charge carriers and external generation of electron and hole charge carriers. This system arises, among other applications, in the context of semiconductor modeling for perovskite solar cells. Thanks to truncation techniques and iterative energy estimates, we show the existence and uniform upper and lower bounds on the solutions. The dependency of the bounds on the various parameters of the model is investigated numerically on physically relevant test cases
Prospective Astronomie Astrophysique 2025-2030
No full textL’exercice de prospective Astronomie-Astrophysique (AA) 2025-2030 démontre une nouvelle fois que l’astronomie française s’illustre au plus haut niveau de la compétition internationale, grâce à une communauté qui cherche des réponses aux grandes questions sur l’origine et le devenir de l’Univers et ses objets, tout en inventant et en développant, avec un tissu industriel à la pointe de l’innovation, les instruments nécessaires à cette quête. Pour la prochaine décennie, l’astronomie française va bénéficier d’une place de choix dans son écosystème européen par comparaison à l’astronomie nord-américaine, que ce soit par la mise en service de trois grands observatoires sol complètement inédits bénéficiant d’une forte contribution nationale, CTA, SKA et ELT1, ou par le lancement de missions spatiales de l’ESA sans équivalent, PLATO, Ariel, puis LISA. Une partie de notre succès réside certainement dans la capacité du continent européen depuis 60 ans, avec l’ESO et l’ESA mais aussi grâce à la coordination Astronet, à assurer une planification de la mise en oeuvre de nos feuilles de route qui repose sur un large support des communautés utilisatrices
Evaluating how different versions of ChatGPT align with expert opinions on geriatric script concordance tests
No full textInternational audiencePurpose: Large Language Models (LLMs), such as ChatGPT, are increasingly used in medical education, particularly for training clinical reasoning. Script Concordance Tests (SCTs) are valuable tools for assessing reasoning under uncertainty. Our objective was to evaluate the performance of four ChatGPT versions (3.5, 4, 4o, and 5) on SCTs compared to Geriatric Medicine experts.Methods: Twenty validated SCT questions covering diverse geriatric topics were administered to ChatGPT-3.5, 4, 4o, and 5, as well as a panel of 43 experts. SCTs assess responses on a five-point Likert scale, and scores were calculated using aggregate expert answers as the reference. Performance was analyzed based on alignment with expert majority responses.Results: ChatGPT-3.5 achieved a score of 8/20, aligning with the majority of experts on 15% of responses. ChatGPT-4 and -5 demonstrated significantly improved performance, scoring 15.6/20 and 15.2/20, respectively, and aligning with the majority on 45% of responses. ChatGPT 4o scored 13.6/20, slightly underperforming GPT-4, potentially due to differences in its architecture or training data. While GPT-4 and 5 excelled in reasoning and coherence, GPT-3.5 struggled with nuanced clinical scenarios.Conclusion: ChatGPT-4 and -5 performed comparably to geriatric experts in SCT-based reasoning, highlighting its potential for medical education. It can simulate case discussions, enhance autonomous learning, and support formative assessments. However, limitations such as variability across versions and question-specific challenges emphasize the need for further evaluation of LLMs across broader clinical domains. These findings support the integration of advanced LLMs into medical education to complement traditional teaching methods
Retentissement maxillo-faciale de l'acromégalie : une étude rétrospective observationnelle
No full textIntroduction: acromegaly is a rare endocrine disorder characterized by excessive growth hormone (GH) secretion. Facial feature is the most frequent complaint of the patient. The aim is to review the oral and maxillofacial features of acromegalic patients in a population systematically evaluated by an oral and maxillofacial surgeon Methods: A retrospective study was conducted in two university hospitals, including all acromegalic patients referred to the oral and maxillofacial surgery department between july 2019 and december 2024. Demographic, clinical and radiographical assessments data were collected. Results: a total of 64 patients were included. Macroglossia was the most frequently found feature since 51 (79.6%) patients were affected. More than half the population showed a class III malocclusion, which was linked to a prognathism. The most frequent transversal malocclusion was mandibular transversal excess, which affected 25 (39%) patients. Twelve patients (18.7%) suffered from TMD. The average number of missing teeth was 4.70. Twenty-five patients (39%) exhibited periodontal disease. A total of 30 (46.8%) patients showed an interdental diastema. Fourteen (22.2%) patients exhibited oral tori. Discussion: acromegalic patients may exhibit various oral and maxillofacial presentations outside the stereotypical mandibular prognathism with mandibular diastemata and macroglossia. Mandibular expansion is not only sagittal but also transversal, which may be difficult to correct. On another hand, GH secretion may have a protective effect on periodontium and the temporomandibular joints with a low prevalence of temporo mandibular disorder (TMD) in a high risk of TMD population. Jaw and occlusal modification may be treated using orthodontics combined with orthognathic surgery.Introduction : l’acromégalie est une pathologie endocrinienne rare, caractérisée par une hypersécrétion d’hormone de croissance (GH). La modification de l’apparence faciale constitue la plainte la plus fréquente des patients. L’objectif de cette étude est de décrire les caractéristiques oro-maxillo-faciales des patients acromégales dans une population évaluée systématiquement par un chirurgien maxillo-facial. Méthodes : une étude rétrospective a été menée dans deux centres hospitaliers universitaires, incluant tous les patients acromégales adressés au service de chirurgie maxillo-faciale entre juillet 2019 et décembre 2024. Les données démographiques, cliniques et radiographiques ont été recueillies. Résultats : un total de 64 patients a été inclus. La macroglossie était la manifestation la plus fréquente, touchant 51 patients (79,6 %). Plus de la moitié des patients présentaient une malocclusion de classe III, en lien avec un prognathisme. L’anomalie transversale la plus fréquente était un excès transversal mandibulaire, observé chez 25 patients (39 %). Douze patients (18,7 %) présentaient des troubles de l’articulation temporo-mandibulaire (ATM). Le nombre moyen de dents manquantes était de 4,70. Vingt-cinq patients (39 %) présentaient une atteinte parodontale. Un diastème interdentaire était retrouvé chez 30 patients (46,8 %). Quatorze patients (22,2 %) présentaient des torus oraux. Discussion : les patients acromégales peuvent présenter diverses manifestations oro-maxillo-faciales au-delà du tableau classique associant promandibulie, diastèmes mandibulaires et macroglossie. La croissance mandibulaire est non seulement sagittale mais également transversale, ce qui peut compliquer sa prise en charge. Par ailleurs, la sécrétion de GH pourrait exercer un effet protecteur sur le parodonte et l’articulation temporo- mandibulaire, expliquant la faible prévalence de troubles de l’ATM dans cette population pourtant à risque. Les modifications dento-squelettiques peuvent être traitées par une prise en charge orthodontique associée à une chirurgie orthognathique