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CHEX-MATE: exploring the kinematical properties of Planck galaxy clusters
No full textInternational audienceWe analyse the kinematical properties of the CHEX-MATE (Cluster HEritage project with XMM-Newton - Mass Assembly and Thermodynamics at the Endpoint of structure formation) galaxy cluster sample. [...] We derive cluster mass profiles for 75 clusters using the \textsc{MG-MAMPOSSt} procedure, which recovers the gravitational potential and the anisotropy profiles from line-of-sight velocities and projected positions of galaxy members. The standard NFW and the Burkert models with flatter cores than NFW both adequately fit the kinematic data, with only marginal statistical preference for one model over the other. An estimation of the mass bias is performed from the comparison with SZ-X-ray-calibrated mass estimates, resulting in a value of when four evidently disturbed clusters are removed from the sample. We assess the dynamical state of the clusters by inferring the Anderson-Darling coefficient and the fraction of galaxies in substructures (). Except for a few cases, we found relatively low values for , suggesting that CHEX-MATE clusters are not too far from relaxation. Moreover, no significant trends emerge among and the difference between the log-masses estimated by \textsc{MG-MAMPOSSt} and by SZ-X-ray. We study the concentration-mass relation for the sample; despite the large scatter, we observe signs of an increasing trend for large-mass clusters, in agreement with recent theoretical expectations. Finally, the analysis of radial anisotropy profiles of member galaxies - stacked in five bins of mass and redshift - reveals that orbits tend to be isotropic at the center and more radial towards the edge, as already found in previous studies. A slight trend of increasing radial orbits at is observed in clusters with larger velocity dispersio
Effective integration of drone technology for mapping and managing palm species in the Peruvian Amazon
No full textInternational audienceRemote sensing data could increase the value of tropical forest resources by helping to map economically important species. However, current tools lack precision over large areas, and remain inaccessible to stakeholders. Here, we work with the Protected Areas Authority of Peru to develop and implement precise, landscape-scale, species-level methods to assess the distribution and abundance of economically important arborescent Amazonian palms using field data, visible-spectrum drone imagery and deep learning. We compare the costs and time needed to inventory and develop sustainable fruit harvesting plans in two communities using traditional plot-based and our drone-based methods. Our approach detects individual palms of three species, even when densely clustered (average overall score, 74%) with high accuracy and completeness for Mauritia flexuosa (precision; 99% and recall; 81%). Compared to plotbased methods, our drone-based approach reduces costs per hectare of an inventory of Mauritia flexuosa for a management plan by 99% (USD 5 ha -1 versus USD 411 ha -1 ), and reduces total operational costs and personnel time to develop a management plan by 23% and 36%, respectively. These findings demonstrate how tailoring technology to the scale and precision required for management, and involvement of stakeholders at all stages, can help expand sustainable management in the tropics
Worldwide analysis of microRNA polymorphism variability in domestic goa
No full textInternational audienceMicroRNAs (miRNAs) are a type of small non-coding RNAs involved in the post-transcriptional repression of target mRNA transcripts, and responsible for the fine-tuning of numerous molecular mechanisms regulating cell metabolism. The presence of single nucleotide polymorphisms (SNP) in miRNA genes is known to affect their expression dynamics and binding affinity toward targeted mRNAs, thus potentially modifying gene regulatory networks. Since domestication, goats have spread worldwide adapting to diverse environmental conditions. However, a comprehensive analysis of how evolutionary forces across and within continental regions have influenced the genome-wide distribution of miRNA polymorphisms in domestic goats is still lacking. By using whole-genome sequencing data from 1,059 domestic goats with African, Asian, American and European origins, we have identified SNPs located within and around goat miRNA genes. In doing so, we have found that miRNA SNPs display very low alternative allele frequencies (median alternative allele frequency of 0.38%) and that the distribution of SNPs within and around miRNA genes is uneven. Remarkably, the stem, loop and neighboring regulatory regions of precursor miRNA hairpins show a significantly higher SNP density compared with the miRNA seed, which determines the binding affinity to target mRNAs. This outcome is probably explained by the occurrence of strong purifying selection removing polymorphisms with potential effects on gene regulatory networks linked to miRNA function. Moreover, we have detected a differential segregation of miRNA SNPs across and within continental regions, with an enriched segregation of putatively high impact polymorphisms, i.e., those located in the seed and other biologically relevant regions of miRNA genes, in isolated goat populations with a low census and reduced heterozygosity. Such information could be useful to investigate the phenotypic consequences of miRNA polymorphisms disrupting gene regulatory networks in domestic goats, as well as to assess their potential impact on adaptation and fitness
The excited state of the -particle: a benchmark study
No full textInternational audienceA benchmark study is performed for the excited state of He. When the Coulomb interaction is switched off, the He nucleus exhibits a bound excited state in the vicinity of H threshold. As the Coulomb interaction is gradually introduced, the excited state crosses the threshold and eventually becomes a resonant state. Using three numerical methods, we track the evolution of this excited state and determine the resonance energy and width. Comparisons of the theoretical predictions reveal a significant discrepancy with commonly used -matrix values based on the analysis of the experimental data. We explain the origin for this discrepancy. Additionally, the two-level energy spectrum of He in the absence of the Coulomb force exhibits characteristics linked to Efimov physics, suggesting a reduced sensitivity to interaction details
Proton therapy for adult type IDH-mutated glioma: Proglio-1, a multicenter retrospective study
No full textISTCT CLINInternational audienceBackground Gliomas with isocitrate dehydrogenase (IDH) mutation affect young adults with a long-life expectancy. While radiotherapy is effective, studies have shown its detrimental effects on cognition and quality of life. Unlike photon radiotherapy, proton therapy better spares healthy tissue. This study aimed to report mid-term survival and toxicities of proton therapy in a multicentric cohort of adults with IDH-mutant gliomas.MethodsWe retrospectively analyzed 90 patients treated with proton therapy in France since 2016, including 60 with IDH-mutated astrocytomas and 30 with oligodendrogliomas. Overall survival (OS) and progression-free survival (PFS) were estimated by Kaplan-Meier and compared with the log-rank test. Prognostic factors were assessed using univariate Cox models. Toxicities, radiation-induced-contrast-enhancement (RICE) and patterns of recurrence were evaluated.ResultsAt the time of proton therapy, World Health Organization (WHO) pathology grades 2, 3, and 4 were observed in 42%, 54%, and 3% of patients, respectively. Protons were delivered as upfront therapy in 41 patients and after recurrence in 49. After a median follow-up of 27.3 months, median OS was not reached, and median PFS was 42.5 months for the whole cohort. WHO grades 3-4 had lower PFS than WHO grade 2 (p = 0.044). Patterns of recurrence were in-field (79%), out-of-field (7%), borderline (4%), and mixed (11%). Proton therapy was well tolerated, with only three grade > 2 toxicities. RICE occurred in 23 patients, but 74% of them did not require any treatment.Conclusions Proton therapy in IDH-mutated gliomas shows a favorable mid-term tolerance and efficacy profile
Euclid preparation: TBD. The impact of line-of-sight projections on the covariance between galaxy cluster multi-wavelength observable properties -- insights from hydrodynamic simulations
No full textInternational audienceCluster cosmology can benefit from combining multi-wavelength studies, which can benefit from characterising the correlation coefficients between different mass-observable relations. In this work, we aim to provide information on the scatter, the skewness, and the covariance of various mass-observable relations in galaxy clusters in cosmological hydrodynamic simulations. This information will help future analyses to better tackle accretion histories and projection effects and model mass observable relations for cosmology studies.We identify galaxy clusters in Magneticum Box2b simulations with mass M_{\rm 200c}>10^{14} {\rm M}_\odot at redshift and . Our analysis includes \Euclid-derived properties such as richness, stellar mass, lensing mass, and concentration. Additionally, we investigate complementary multi-wavelength data, including X-ray luminosity, integrated Compton- parameter, gas mass, and temperature. The impact of projection effects on mass-observable residuals and correlations is then examined. At intermediate redshift (), projection effects impact lensing concentration, richness, and gas mass the most in terms of scatter and skewness of log-residuals of scaling relations. The contribution of projection effects can be significant enough to boost a spurious hot- vs. cold-baryons correlation and consequently hide underlying correlations due to halo accretion histories. At high redshift (), the richness has a much lower scatter (of log-residuals), and the quantity that is most impacted by projection effects is the lensing mass. Lensing concentration reconstruction, in particular, is affected by deviations of the reduced-shear profile shape from the one derived by an NFW profile rather than interlopers in the line of sight
Experimental realization of a SU(3) color-orbit coupling in an ultracold gas
No full textInternational audienceSpin-orbit interaction couples the spin of a particle to its motion and leads to spin-induced transport phenomena such as spin-Hall effects and Chern insulators. In this work, we extend the concept of internal-external state coupling to higher internal symmetry, exploring features beyond the established spin-orbit regime. We couple suitable resonant laser beams to a gas of ultracold atoms, thereby inducing artificial SU(3) non-Abelian gauge fields that act on a degenerate ground state manifold comprised of three dark states. We demonstrate the inherent all-state connectivity of SU(3) systems by performing targeted geometric transformations. Then, we investigate color-orbit coupling, an extension of SU(2) spin-orbit coupling to SU(3) systems. We reveal a rich dynamical interplay between three distinct oscillation frequencies, which possesses interesting analogies with neutrino oscillations and quark mixing mechanisms. In the future, the system should provide a testbed for exploring topological properties of SU(3) systems
Exposition à l'écrit et développement de la lecture dans le système éducatif français : Une revue systématique.
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Euclid VI. NISP-P optical ghosts
No full textInternational audienceThe Near-Infrared Spectrometer and Photometer (NISP) onboard Euclid includes several optical elements in its path, which introduce artefacts into the data from non-nominal light paths. To ensure uncontaminated source photometry, these artefacts must be accurately accounted for. This paper focuses on two specific optical features in NISP's photometric data (NISP-P): ghosts caused by the telescope's dichroic beamsplitter, and the bandpass filters within the NISP fore-optics. Both ghost types exhibit a characteristic morphology and are offset from the originating stars. The offsets are well modelled using 2D polynomials, with only stars brighter than approximately 10 magnitudes in each filter producing significant ghost contributions. The masking radii for these ghosts depend on both the source-star brightness and the filter wavelength, ranging from 20 to 40 pixels. We present the final relations and models used in the near-infrared (NIR) data pipeline to mask these ghosts for Euclid's Quick Data Release (Q1)
Low-latency Forecasts of Kilonova Light Curves for Rubin and ZTF
No full textInternational audienceFollow-up of gravitational-wave events by wide-field surveys is a crucial tool for the discovery of electromagnetic counterparts to gravitational wave sources, such as kilonovae. Machine learning tools can play an important role in aiding search efforts. We have developed a public tool to predict kilonova light curves using simulated low-latency alert data from the International Gravitational Wave Network during observing runs 4 (O4) and 5 (O5). It uses a bidirectional long-short-term memory (LSTM) model to forecast kilonova light curves from binary neutron star and neutron star-black hole mergers in the Zwicky Transient Facility (ZTF) and Rubin Observatory's Legacy Survey of Space and Time filters. The model achieves a test mean squared error (MSE) of 0.19 for ZTF filters and 0.22 for Rubin filters, calculated by averaging the squared error over all time steps, filters, and light curves in the test set. We verify the performance of the model against merger events followed-up by the ZTF partnership during O4a and O4b. We also analyze the effect of incorporating skymaps and constraints on physical features such as ejecta mass through a hybrid convolutional neural network and LSTM model. Using ejecta mass, the performance of the model improves to an MSE of 0.1. However, using full skymap information results in slightly lower model performance. Our models are publicly available and can help to add important information to help plan follow-up of candidate events discovered by current and next-generation public surveys