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Ab initio calculations of nuclear charge radii across and beyond Sn: Putting chiral EFT nuclear interactions to the test
No full textInternational audienceCharge radii are investigated along the Tin isotopic chain via ab initio Bogoliubov coupled cluster calculations at the singles and doubles level. In addition to the reproduction of absolute radii, the parabolic behavior of isotopic shifts between the N = 50 and N = 82 magic numbers and the kink through Sn are shown to provide stringent tests for state-of-the-art chiral effective field theory (EFT) inter-nucleon interactions. Indeed, none of the employed fine-tuned interactions can capture all such key characteristics. Eventually, the pronounced sensitivity of the results to the employed Hamiltonian beyond Sn provides a unique playground to pin down critical attributes of EFT inter-nucleon interactions in the future. This calls for measuring isotopic shifts both towards Sn and beyond Sn, as well as for performing high-accuracy ab initio calculations of mean-square radii in heavy open-shell nuclei by adding both triples corrections to the many-body wave function and the two-body charge density correction to the operato
La mitochondrie : un acteur clé dans les déséquilibres intestinaux de l’obésité
No full textNational audienceMetabolic complications of obesity are associated with a loss of intestinal homeostasis and low-grade chronic inflammation. As the energy powerhouses of enterocytes, mitochondria play a key role in maintaining this homeostasis. We investigated whether mitochondrial alterations could contribute to the intestinal hyperpermeability observed in obesity. In mice, excess dietary lipids caused the accumulation of lipid droplets in enterocytes, leading to a reduction in mitochondrial number and activity, associated with a loss of mature epithelial phenotype and barrier function. In murine jejunal organoids, decreased mitochondrial activity limited the differentiation of progenitors into mature enterocytes, potentially promoting hyperpermeability. In the colon, a high-fat diet also induced mitochondrial dysfunction and epithelial hyperpermeability linked to dysbiosis characterized by an abundance of Desulfovibrionaceae and sulfides, inhibitors of mitochondrial complex IV. These findings highlight the key role of mitochondria in intestinal imbalance associated with obesity and open new therapeutic avenues.Les complications métaboliques de l’obésité sont associées à une perte d’homéostasie intestinale et à une inflammation chronique de bas grade. Centrales énergétiques des entérocytes, les mitochondries jouent un rôle clé dans le maintien de cette homéostasie. Nous avons évalué si leur altération pouvait contribuer à l’hyperperméabilité intestinale observée dans l’obésité. Chez la souris, un excès de lipides alimentaires provoque une accumulation de gouttelettes lipidiques dans les entérocytes, entraînant une baisse du nombre et de l’activité mitochondriale, associée à une perte du phénotype mature et de la fonction de barrière. Dans les organoïdes jéjunaux murins, la réduction de l’activité mitochondriale limite la différenciation des progéniteurs en entérocytes matures, pouvant favoriser l’hyperperméabilité. Dans le côlon, le régime hyperlipidique induit aussi une dysfonction mitochondriale et une hyperperméabilité liée à une dysbiose marquée par les Desulfovibrionaceae et les sulfures, inhibiteurs du complexe IV mitochondrial. Ces travaux soulignent le rôle clé des mitochondries dans les déséquilibres intestinaux liés à l’obésité et ouvrent de nouvelles pistes thérapeutiques
Root phenolics as potential drivers of preformed defenses and reduced disease susceptibility in a paradigm bread wheat mixture
No full textInternational audiencePlant-plant interactions modulate foliar disease susceptibility in intraspecific mixtures. However, the molecular events including signals and responses underlying the reduction in disease susceptibility remain largely unexplored. Here, we developed an experimental system that can abolish root-mediated interactions between plants in a model of bread wheat varietal mixture. We then performed transcriptomic and metabolomic analyses to uncover the molecular responses linked to decreased susceptibility to Septoria tritici blotch in plant-plant interactions. Our analysis revealed that disrupting root chemical interactions impaired the reduction in susceptibility to Septoria and identified phenolic compounds as potential key mediators. The plant-plant interactions under study triggered significant molecular changes in specialized metabolism, biotic interactions, transporters, and responses to resources. Disrupting root interactions canceled both the macroscopic and molecular responses, thus providing a strong link between them. These insights provide a deeper understanding of the molecular basis of plant-plant interactions and the processes involved in reducing disease susceptibility in intraspecific mixtures
A Proximal Approach for Stain Separation and Normalization of Whole-Slide Histopathological Images
No full textInternational audienceStain variability in histopathological images presents a major obstacle to developing accurate and reliable computer-aided diagnosis systems. In this paper, we introduce a novel stain normalization framework based on a stain separation proximal algorithm. Specifically, we first propose a new stain separation method that extracts individual stain components from a given stained image. Subsequently, we perform stain normalization by aligning the separated source stains with those of a target reference image. Experimental results demonstrate that the proposed approach effectively reduces inter-image color variations while preserving the essential structural details of the tissue.</div
Effects of deep brain stimulation on non motor fluctuations in Parkinson’s disease (assessed with the NMF severity scale)
No full textInternational audienc
Implementation of a multiresolution analysis method to characterize multi-scale wave structures in lidar data
No full textInternational audienceExtracting gravity wave (GW) perturbations from atmospheric observations relies on background removal tech- niques whose results may differ depending on the obser- vational type and the spectral characteristics of the chosen method. This variability complicates the intercomparison of GW properties across instruments, sites, and studies. Night- time averaging provides a simple estimate of the background but may smooth out smaller-scale structures. Spectral filter- ing enables targeted wavelength extraction, though it can be sensitive to noise and edge effects. Sliding polynomial fit of- fers flexibility but may suppress relevant signals depending on the polynomial degree. To address this issue, we imple- ment and evaluate a processing method based on multireso- lution analysis (MRA), designed to better extract and charac- terize the background and the multi-scale structures of GWs in lidar temperature and wind profiles. The MRA approach is then evaluated in comparison to these techniques and applied to lidar temperature and wind measurements collected on the night of 20 November 2023 at La Réunion. By decomposing the signal into dyadic vertical wavelength bands and an ap- propriate choice of corresponding details, the MRA can im- prove the detection of GW-induced perturbations in the spec- tral range of 0.8 to 12.8 km vertical wavelength by simulta- neous background removal and denoising. We use the vari- ance method as a benchmark for determining gravity waves potential energy (GWPE) and ask the question: “How well do the different filtering techniques compare with the vari- ance method?” Given an overall agreement between our de- velopped MRA and the variance method, we conclude thatthe MRA can also be used to determine reliable gravity wave kinetic energy (GWKE).Beyond energy estimation, MRA provides a unique capa- bility to compute kinetic and potential energy profiles for tunable vertical wavelength bands, enabling the characteri- zation of vertical and temporal evolution and interactions be- tween different GW scales. These results establish MRA as a robust and complementary tool for improving GW analy- ses from lidar measurements, with promising applications to long-term climatologies and multi-instrument observational strategies
A Super-Pangenome for Cultivated Citrus Reveals Evolutive Features During the Allopatric Phase of Their Reticulate Evolution
No full textData availability: Raw data from long-read sequencing and genome assemblies of C. micrantha, C. medica and C. reticulata were deposited at EBI under the following accession numbers: - CITMI (C. micrantha): Raw data: PRJEB78372 - Assemblage: PRJEB78515 - Umbrella: PRJEB78526 - CITME (C. medica): Raw data: PRJEB78445 - Assemblage: PRJEB78498 - Umbrella: PRJEB78525- CITRE (C. reticulata): Raw data: PRJEB78477 - Assemblage: PRJEB78537 - Umbrella: PRJEB78524Resequencing raw reads derived from 58 citrus accessions were deposited in the EBI database under AC experiment accessions ERX12760151, ERX12780957, ERX12791201 and ERX12817346 to ERX12817400 (supporting information, Table 1).The raw RNA-seq data for C. medica, C. reticulata, C. maxima and C. micrantha were deposited in the European Nucleotide Archive under accession code PRJEB77075. The pseudochromosome and chloroplast genome assemblies of C. medica, C. reticulata and C. micrantha and their annotations are available on: https://citrus-genome-hub.southgreen.fr.International audienceThe main genetic diversity observed in cultivated citrus results from a reticulate evolution involving four ancestral taxa whose radiation occurred in allopatry. In such context, GWAS analysis, genome diversity and transcriptomic studies will be significantly enhanced through pangenome approaches. We report the implementation of a super-pangenome for cultivated citrus, established with de novo assemblies of C. medica, C. reticulata and C. micrantha, released for the first time alongside a published chromosome-scale assembly of C. maxima. Repetitive element annotation revealed that half of each genome consisted of transposable elements or DNA-satellites. The new genome assemblies display strong synteny and collinearity, while discrepancies are observed with the C. maxima assembly. Resequencing information from 55 accessions helped to explore the intra- and interspecific diversity of the ancestral taxa and their relationships with horticultural groups. Diagnostic SNPs of the ancestral taxa revealed interspecific introgressions in several representative accessions of C. reticulata, C. maxima and C. medica as well as insights into the origin and phylogenomic structures of horticultural groups. PAV analysis revealed a gene whose absence or presence was specific to one of the ancestral taxa. Diagnostic PAV analysis uncovered a large chloroplastic introgression in C. medica chromosome 4. The analysis of the functional enrichment and species-specific adaptations in the citrus super-pangenome revealed distinct functional specialisations. This highlights the evolutionary paths that have shaped species, contributing to the diversity in the citrus super-pangenome while maintaining a shared foundation of essential biological processes. We established a Genome Hub, offering a platform for continuous genomic research
Local specialists' experience and skills in animal behaviour studies: insights from wild chimpanzee field assistants
No full textInternational audienceThe study of wild animal behaviour and cognition has greatly benefited from the foundational work of local specialists (LSs), particularly field assistants. In primate research, long-term studies rely on accurate identification and tracking of individuals—a skill often honed by LSs and passed on to international specialists (ISs). Despite growing recognition in publications, LSs' scientific contributions often remain undervalued. Here, we show that LSs at the Budongo Conservation Field Station (Uganda) reliably extract acoustic information (caller identity, sex and age, call components and production context) from long-distance pant hoot calls produced by wild chimpanzees. Importantly, LSs significantly outperform ISs at identifying individuals (LS accuracy = 50% (95% confidence interval (CI): 45–56%); IS accuracy = 8% (95% CI: 5–11%)), an important skill for recognizing and locating individuals in dense forests. LSs' performance was positively associated with duration of working experience. Given the limited field time of ISs (typically 1–2 years), LSs' expertise and longer commitment (mean 16.75 years) represent an essential yet underacknowledged scientific resource. Our study highlights LSs' critical role in ethological research—not only enhancing skills and data quality, but also potentially helping address both ethical (e.g. community involvement) and environmental (e.g. travel carbon footprint) challenges linked to fieldwork in remote locations
Optimal patient care in advanced chronic kidney disease progressing to kidney failure
No full textInternational audienceThe transition from advanced chronic kidney disease (CKD) to kidney failure requires comprehensive management to optimize patient outcomes. This crucial period, in practical terms defined by CKD stages G4 and G5, involves complex decision-making regarding kidney replacement therapy, pre-emptive kidney transplantation and conservative kidney management. Patient preferences, quality of life, and comorbidities, especially cardiovascular disease, are essential considerations when making treatment decisions. Importantly, nephroprotective therapies should be continued even at advanced stages of CKD to stabilize kidney function and prevent cardiovascular events. Pre-emptive kidney transplantation, when feasible, offers the best outcomes and should be prioritized. Dialysis initiation should be based on clinical symptoms and shared decision-making with the patient, rather than laboratory values alone. For some, particularly older, patients with substantial comorbidities, conservative kidney management, emphasizing symptom management without kidney replacement therapy, might be preferred. Considerable disparities in access to care exist globally, especially in low- and middle-income countries, highlighting the need for tailored strategies. Registry and cohort studies have provided most of the scientific understanding in this area, but more randomized clinical trials are needed to guide advanced CKD management
Decreasing frequency and extent of frost damage in European oaks over 1961-2021
No full textInternational audienceLate spring frosts (LSF) have substantial ecological and economic impacts in the temperate and boreal zones. Yet, the effects of climate warming on the frequency (i.e., probability of LSF in a given year, in %) and extent (i.e., percentage of trees in a population damaged by a given LSF event) of LSF damage remain underexplored. Here, extending a budburst model that accounts for within-population variability, we developed and evaluated a new model of LSF damage occurrence and extent using 1,220 observations of LSF damage to newly emerged leaves from 304 oak populations in France (1997-2021). Our model simulations reveal that overall, French oak populations are, over time, less exposed to LSF amid ongoing climate change. We observed an overall decline in the frequency (-0.22 % per year) and extent (-0.34 % per year) of LSF damage in French oak populations over the past six decades (1961-2021). These trends are largely driven by the temporal advance of both the last spring frost day and budburst dates, with the last spring frost day advancing at a slightly faster rate (-0.28 days per year) than budburst (-0.21 days per year). This temporal mismatch explains why, contrary to the common assumption that earlier budburst increases frost risk, earlier budburst was in fact associated with a lower frequency of LSF damage. Nevertheless, considerable geographical variability emerged, with declines in damage frequency being more pronounced in continental regions, whereas declines in damage extent were more pronounced in coastal regions. Our findings underscore the importance of considering both LSF frequency and extent when assessing frost risks in a warming climate, offering a comprehensive framework for future ecological and economic evaluations of LSF impacts.</div