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Quantitative monitoring of ketamine's impact on synaptic density using 11C-UCB-J PET imaging in the corticosterone mouse model of anxiety/depression
No full textInternational audienceKetamine was shown to promote synaptogenesis, which is thought to account for its antidepressant effects through the restoration of lost synaptic connections observed in depression. PET imaging using 11C-UCB-J, a radiotracer targeting the synaptic vesicle protein 2 A (SV2A), was investigated as a translational method to monitor ketamine-induced changes in synaptic density in the corticosterone (CORT) mouse model of anxiety/depression. Male CORT and healthy control mice received either a single dose of ketamine (10 mg/kg, i.p) or a repeated-dose regimen (3 doses in total). Brain PET imaging was performed either 24 h after the single dose or 1 or 3 weeks after the repeated-dose regimen to estimate the binding of 11C-UCB-J in each condition. A global decrease in the binding of 11C-UCB-J was observed in CORT mice compared to control mice, indicating synaptic loss. In CORT mice, behavioral experiments showed antidepressant effects of ketamine 24 h after a single dose, although no significant changes in 11C-UCB-J binding could be observed at this time point. Three weeks after the repeated dose regimen, ketamine restored the binding of 11C-UCB-J in CORT mice to the level of age-matched untreated healthy controls. The reversal of synaptic loss was associated with delayed antidepressant effects in behavioural tests. Ex vivo expression of SV2A protein measured under different conditions was strongly correlated with the in vivo binding of 11C-UCB-J and the postsynaptic marker PSD95. These results support the molecular interpretation of SV2A PET imaging to monitor drug-induced synaptogenesis as a determinant of antidepressant efficacy from a translational perspective
Precipitating electron properties of Ganymede’s aurora retrieved from Juno/UVS observations during PJ34
No full textInternational audienceContext. Ganymede's UV aurorae, observed by HST and Juno/UVS, trace interactions between its atmosphere and Jupiter's magnetosphere. These emissions, dominated by O I lines at 130.4 and 135.6 nm, are driven by electron impact on species such as H 2 O, O, and O 2 , and yet the properties of the precipitating electrons remain poorly constrained. Aims. Our aim was to retrieve the energy and flux of precipitating electrons using UV observations from Juno/UVS during PJ34 and to assess the dominant atmospheric species producing the observed emissions. Methods. Using the TransPlanet electron transport model and a non-local thermodynamic equilibrium (non-LTE) radiative transfer module, we simulated O I emissions for 17 auroral subregions, testing both monoenergetic and kappa-type electron distributions. The I(135.6 nm)/I(130.4 nm) line ratio was used as a diagnostic, with values varying by target species. Results. Monoenergetic distributions fit most regions better, with mean energies of 17-300 eV and fluxes up to 2 mW m -2 . Kappa and Maxwellian distributions yielded higher fluxes, but poorer spectral fits. Poor fits in some regions reflect low S/N or non-ideal electron populations. Conclusions. Our results suggest that Ganymede's UV aurorae are mainly driven by low-to intermediate-energy electrons. Upcoming high-resolution observations and in situ data from Juice and Europa Clipper will be key to refining these diagnostics
Le symphonisme de John Williams : esthétique audiovisuelle et mutations orchestrales
No full textInternational audienceEn s’appuyant principalement sur la collaboration entre Williams, Spielberg et Lucas, le présent article propose de dégager plusieurs traits saillants de l’écriture symphonique du compositeur pour l’industrie hollywoodienne afin d’en saisir les spécificités, en mettant en exergue sa sensibilité profonde à l’image et au son, et la façon dont elle s’est adaptée aux défis de l’ère numérique
X-SHYNE: X-Shooter spectra of young exoplanet analogs
No full textInternational audienceCharacterizing exoplanets’ spectra is a crucial step in understanding the chemical and physical processes shaping their atmospheres and constraining their formation and evolutionary history. The X-SHYNE library is a homogeneous sample of 43 medium-resolution (R λ ~ 8000) infrared (0.3–2.5 μm) spectra of young (<500 Myr), low-mass (<20 M Jup ), and cold (T eff ~600–2000 K) isolated brown dwarfs and wide-separation companions observed with the VLT/X-Shooter instrument. To characterize our targets, we performed a global comparative analysis. We first applied a semiempirical approach. By refining their age and bolometric luminosity, we derived key atmospheric and physical properties, such as T eff , mass, surface gravity (g), and radius, using the evolutionary model COND03 . These results were then compared with the results from a synthetic analysis based on three self-consistent atmospheric models: the cloudy models Exo-REM and Sonora Diamondback , and the cloudless model ATMO . To compare our spectra with these grids we used the Bayesian inference code ForMoSA . We found similar L bol estimates between both approaches, but an underestimated T eff from the cloudy models, likely due to a lack of absorbers that could dominate the J and H bands of early L. We also observed a discrepancy in the log(g) estimates, which are dispersed between 3.5 and 5.5 dex for mid-L objects. We interpret this as a bias caused by a range of rotational velocities leading to cloud migration toward equatorial latitudes, combined with a variety of viewing angles that result in different observed atmospheric properties (cloud column densities, atmospheric pressures, etc.). This interpretation is supported by the correlation of the color anomaly Δ(J–K) of each object with log(g) and the parameter f sed that drives the sedimentation of the clouds. Finally, while providing robust estimates of [M/H] and C/O for individual objects remains challenging, the X-SHYNE library globally suggests solar values that are consistent with a formation via stellar formation mechanisms. This study highlights the strength of homogeneous datasets in performing comparative analyses, reducing the impact of systematics, and ensuring robust conclusions while avoiding overinterpretation.28 pages, 18 figures, 6 table
Infrared Borderlands: Belt and Road Initiative and local planning - Khorgos interdependencies, imaginaries and territorial realities
No full textInternational audienceThis article examines the role of Khorgos, a special economic zone located on the border between China and Kazakhstan, within the framework of China's Belt and Road Initiative (BRI). In less than a decade, Khorgos has become a strategic hub for rail freight between China and Europe, increasing from 25 trains in 2013 to more than 8,700 in 2024, reflecting China's efforts to strengthen overland connectivity and establish alternative corridors to maritime trade. This paper, drawing on satellite data and spatial analysis through remote sensing, focuses on three main dimensions. First, it analyses the peripheral urbanisation of the city of Khorgos, which is embedded in China's territorial strategies to connect the western region to the rest of the country through infrastructure development, securitisation, and territorial control. Second, it situates Khorgos within a regional scale, namely the Khorgos-Yining-Qingshuihe economic complex. This analysis highlights the functional division of employment between Yining, the true administrative centre, Qingshuihe as the production core, and Khorgos, which remains primarily a transit point for Chinese exports, thereby illustrating an asymmetry in cross-border exchanges with Kazakhstan. Third, the paper examines territorial production and environmental differentiation. Remote sensing analyses reveal pronounced asymmetries in land use and ecological transformations between the Chinese and Kazakh sides of the border: China has developed a diversified and tightly regulated territorial model, combining urban and agricultural infrastructures, whereas the Kazakh side remains less structured and less developed. Chinese ecological initiatives, such as photovoltaic projects and urban greening policies, further reinforce cross-border territorial asymmetries and raise critical questions about the actual impacts of the BRI and the associated "win-win" cooperation rhetoric
Asymptotic stability of solitons for near-cubic NLS equation with an internal mode
No full textInternational audienc
Knowledge graph to dissect genotype phenotype associations
No full textInternational audienceDefining the mechanisms underlying complex traits and phenotypes requires understanding their genetic basis and how genes interact with environmental and lifestyle factors. Population-based prospective cohorts provide valuable resources for such research, collecting extensive phenotypic and omics data. However, the wide range of phenotypes in these cohorts makes it difficult to define homogeneous and/or clinically meaningful subgroups, limiting traditional genome-wide association studies (GWAS).We aim to develop a novel graph-based methodology to identify genotypephenotype associations. Our method represents data as a graph, where nodes correspond to variables (e.g., participants, phenotypes), and edges represent relationships between them. These edges can connect the same type of nodes (for example, participant-participant interactions) or different types (for example, bipartite interactions connecting participant to SNP). We applied our approach to the GOLD project, which includes comprehensive information on medical conditions, drug consumption, demographics, and genotypes of 10,000 participants. The graph contains four node types (participant, drug, SNP, phenotype) and 10 edge types, with attributes such as drug reimbursements, genotypes, and participant similarity.This knowledge graph representation allows us to use graph theory tools, including clustering algorithms, random walks, and deep learning-based graph representation methods. We expect to detect weak genotype-phenotype association signals that could not be detected by GWAS
Buu-Sao Doris, 2023, Le capitalisme au village. Pétrole, État et luttes environnementales en Amazonie. Paris, CNRS Éditions, 320 p.
No full textInternational audienc
Séminaire de Probabilités LII
No full textIncludes a tribute to Dominique LépingleInternational audienc
Oncology pharmacy practice: Key insights, challenges, and perspectives – A position paper from the French Society for Oncology Pharmacy (SFPO)
No full textInternational audienceThe role of hospital oncology pharmacists (HOP) in the care of cancer patients has evolved considerably. This evidence led the experts of the French Society for Oncology Pharmacy (SFPO) to write a position paper. The first part presents the key insights of oncology pharmacy services (technology aspects of anticancer drug preparation and clinical pharmacy services), training of HOPs and research activities (clinical trials, research in oncology pharmacy). The second part of this position paper refers to the challenges and perspectives of E-health and artificial intelligence, precision medicine, access to innovation, and environmental issues