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Transcriptional outputs and condensates – formation and function
No full textInternational audienceThe dynamic spatiotemporal organization of macromolecules is key to the proper function of the cell, allowing the exquisite regulation of diverse processes from gene expression to enzymatic function. The formation of biomolecular condensates via phase separation (PS) acts as a general mechanism for selectively concentrating proteins, nucleic acids and metabolites in membraneless compartments and thus modulating their activity. Recent studies suggest that plants broadly exploit PS to perceive and quickly respond to their environment, altering transcriptional outputs as a function of changing environmental stimuli. Here, we provide examples of how PS properties contribute to modulating plant environmental response with a focus on gene expression at the transcriptional level and discuss the mechanisms of action of phase‐separating proteins and the importance of specific protein–protein interactions for nucleation of PS
Association Between Metabolic Syndrome, Obesity, and Cognitive Performances in Individuals With Bipolar Disorders: Cross‐Sectional and Longitudinal Analyses in the FACE ‐ BD Cohort
No full textInternational audienceIntroduction: Metabolic syndrome (MetS) has been suggested to be associated with cognitive impairments in bipolar disorder (BD); however, studies are limited by small sample sizes or cross-sectional design. Our objective is to evaluate the cross-sectional and longitudinal associations between MetS and cognitive performances in a large cohort of individuals with BD.Methods: 1175 individuals with a DSM-IV diagnosis of BD were included from the FACE-BD cohort, assessed with a standardized battery of clinical and neuropsychological tests and followed up with a cognitive retest at 2 years for a subsample (n = 367). A global cognitive index was created by using a Principal Component Analysis. Associations between MetS and cognitive performances at baseline were explored using multiple analyses of covariance and linear mixed models were used for longitudinal data.Results: The prevalence of MetS was 21.5% in this sample. Multivariable analyses identified associations between MetS and poorer cognitive performance in the cross-sectional analysis, independently of age, gender, education level, psychotropic treatments, and comorbidities. Specifically, individuals with MetS showed poorer results (global cognitive index, cognitive flexibility, inhibition, and verbal memory). After adjustment, the longitudinal analysis showed no change in the global cognitive index at year 2 and no time × metabolic syndrome interaction.Conclusions: Our results suggest that MetS is cross-sectionally, but not longitudinally, associated with poorer cognitive performances in BD. This study highlights the importance of systematically and accurately screening for metabolic abnormalities in individuals with BD, and screening for cognitive deficit especially in individuals with MetS. Our results suggest that MetS is not a risk factor for cognitive decline during the follow-up, but further longitudinal studies are required
Uncertainty in projected changes of Indian Summer Monsoon Rainfall by CMIP6 models
No full textInternational audienceA robust and trustworthy rainfall projection over the Indian landmass is vital for devising climate adaptation strategies. However, past studies show large inter-model spread in Indian Summer monsoon (ISM) rainfall projections thus calling for more detailed investigations on the underlying process. In the present study, we investigate this aspect using Coupled Model Intercomparison Project Phase 6 (CMIP6) model projections (Shared Socioeconomic Pathways, SSP5–8.5) and historical simulations. The Multi-Model Ensemble mean (MME) results show intensification of ISM rainfall at the end of the 21st century with ISM rainfall increasing by 1.6 ± 0.8 mm/day under SSP5–8.5 scenario. A moisture budget analysis for the MME further infers that the thermodynamic effect (TH) due to global warming plays a dominant role in enhancing ISM rainfall in the projections, with its dynamic counterpart (DY) assuming an additional contribution. It is also revealed that both DY and TH terms contribute to the inter-model uncertainty in ISM rainfall, but with DY dominating over the other this time. The inter-model uncertainty in DY and ISM rainfall changes is linked to inter-model spread in interhemispheric thermal contrast which in-turn depends on the diversity in Equilibrium Climate Sensitivity (ECS) and Global Mean Temperature (GMT) among the models. Intriguingly, when we remove the inter-model diversity in ECS through a GMT scaling, an Atlantic meridional surface temperature gradient, involving both land and ocean, emerges as a crucial driver in controlling the uncertainty in both DY and ISM rainfall changes, and drives large-scale monsoon circulation changes over African and the Indian subcontinents
Matrix Elements and Characters of the Discrete Series ("Massive") Unitary Irreducible Representations of Sp(4,R)
No full textInternational audienceThis paper obtains the matrix elements and characters of the discrete series unitary irreducible representations (UIRs) of the Sp group. With an isomorphic relationship to the two-fold covering of SO (Sp SO), this group holds particular importance as the kinematical/relativity group within the framework of (-dimensional) anti-de Sitter spacetime
Euclid preparation. Galaxy 2-point correlation function modelling in redshift space
No full textInternational audienceThe Euclid satellite will measure spectroscopic redshifts for tens of millions of emission-line galaxies. In the context of Stage-IV surveys, the 3-dimensional clustering of galaxies plays a key role in providing cosmological constraints. In this paper, we conduct a model comparison for the multipole moments of the galaxy 2-point correlation function (2PCF) in redshift space. We test state-of-the-art models, in particular the effective field theory of large-scale structure (EFT), one based on the velocity difference generating function (VDG), and different variants of Lagrangian perturbation theory (LPT) models, such as convolutional LPT (CLPT) and its effective-field-theory extension (CLEFT). We analyse the first three even multipoles of the 2PCF in the Flagship 1 simulation, which consists of four snapshots at . We study both template-fitting and full-shape approaches and find that with the template-fitting approach, only the VDG model is able to reach a minimum fitting scale of at without biasing the recovered parameters. Indeed, the EFT model becomes inaccurate already at . Conversely, in the full-shape analysis, the CLEFT and VDG models perform similarly well, but only the CLEFT model can reach while the VDG model is unbiased down to at the lowest redshift. Overall, in order to achieve the accuracy required by Euclid, non-perturbative modelling such as in the VDG or CLEFT models should be considered. At , the CLPT model is sufficient to describe the data with high figure of merit. This comparison selects baseline models that perform best in ideal conditions and sets the stage for an optimal analysis of Euclid data in configuration space
Influence of 3 T magnetic field on RF plasma self-bias and erosion pattern for the ITER wide angle viewing system
No full textInternational audienceThe ITER Wide Angle Viewing System (WAVS) relies on in-vessel metallic first mirrors (FM) to transport optical signals from the plasma to out-of-vessel diagnostics. Under the conditions of ITER, energetic plasma particles induce sputtering of plasma-facing components, and the resulting sputtered material can re-deposit on these mirrors, resulting in reflectivity degradation. In-situ plasma removal using radio-frequency (RF) capacitively coupled plasma discharges is one of the proposed methods to mitigate this issue. Experiments were conducted in a 3 T homogeneous magnetic field using a medical magnetic resonance imaging (MRI) system at the University Hospital of Basel. The WAVS First Mirror Unit consists of two mirror electrodes (M1 and M2), one or both of which can be powered with RF, while the remaining surfaces act as grounded areas. Systematic measurements of the self-bias voltage were performed for varying discharge conditions, including gas species (argon and helium), pressure (0.1-10 Pa) and mirror capacitance, as well as the angle θ between the mirror surface and magnetic field. The results revealed a strong dependence of the self-bias on the grounded-to-powered area ratio A g /A p , which is affected by the magnetic confinement. Erosion and deposition patterns were examined in cases where one or both mirrors were powered. Erosion occurred primarily where a powered mirror faces a grounded surface, whereas overlapping discharges in the dual-powered case resulted in low ion kinetic energy and preferential net deposition at the overlapping area.</div
Toward unprivileged, portable and generic network topology discovery
No full textInternational audienceWith the increase in size and complexity of supercomputers, it has become crucial to match applications and communication libraries to the underlying network topology. This matching may allow minimizing the time spent in waiting for high-latency communication and limiting contention on the network. While MPI implementations rely mostly on software such as hwloc to retrieve information about nodes topology, no tool currently gathers network topology information in a generic and portable fashion.In this paper, we propose an algorithm inspired by the Steiner Spanner problem that exploits end-to-end latency measurements to reconstruct a network topology. Our solution reconstructs the topology graph from a matrix of measured communication times. This is achieved by iteratively adding nodes to the graph while trying to match the shortest path length in the graph to the communication times. The total weight and the number of edges in the graph are also minimized
Land surface model underperformance tied to specific meteorological conditions
No full textInternational audienceThe exchange of carbon, water, and energy fluxes between the land and the atmosphere plays a vital role in shaping global change and extreme events. Yet our understanding of the theory of this surface-atmosphere exchange, represented via land surface models (LSMs), continues to be limited, highlighted by marked biases in model-data benchmarking exercises. Here, we leveraged the PLUMBER2 dataset of observations and model simulations of terrestrial sensible heat, latent heat, and net ecosystem exchange fluxes from 153 international eddy-covariance sites to identify the meteorological conditions under which land surface models are performing worse than independent benchmark expectations. By defining performance relative to three sophisti-cated out-of-sample empirical models, we generated a lower bound of performance in turbulent flux prediction that can be achieved with the input information available to the land surface models during testing at flux tower sites. We found that land surface model performance relative to empirical models is worse at edge conditions -that is, LSMs underperform in timesteps where the meteorological conditions consist of coinciding relative extreme values. Conversely, LSMs perform much better under "typical" conditions within the centre of the meteorological variable distributions. Constraining analysis to exclude the edge conditions results in the LSMs outperforming strong empirical benchmarks. Encouragingly, we show that refinement of the performance of land surface</div
Accessible Quantum Gates on Classical Stabilizer Codes
No full textInternational audienceWith the advent of physical qubits exhibiting strong noise bias, it becomes increasingly relevant to identify which quantum gates can be efficiently implemented on error-correcting codes designed to address a single dominant error type. Here, we consider -classical stabilizer codes addressing bit-flip errors where , and are the numbers of physical and logical qubits, and the code distance respectively. We prove that operations essential for achieving a universal logical gate set necessarily require complex unitary circuits to be implemented. Specifically, these implementation circuits either consists of layers of -transversal operations on codeblocks such that or of gates, each operating on at most physical qubits on the same codeblock, such that . Similar constraints apply not only to classical codes designed to correct phase-flip errors, but also to quantum stabilizer codes tailored to biased noise. This motivates a closer examination of alternative logical gate constructions using eg.~magic state distillation and cultivation within the framework of biased-noise stabilizer codes
The North Balearic Front as an ecological boundary: zooplankton fine-scale distribution patterns in late spring
No full textInternational audienceObservations, models and theory have suggested that ocean fronts are ecological hotspots, generally associated with higher diversity and biomass across many trophic levels. Nutrient injections are often associated with higher chlorophyll concentrations at fronts, but the response of the zooplankton community is still insufficiently understood. The present study investigates mesozooplankton stocks and composition during late spring, northeast of Menorca, along two north-south transects that crossed the North Balearic Front separating central waters of the Northwestern Mediterranean Sea gyre from peripheral waters originating from the Algerian basin. During the BioSWOT-Med campaign, vertical triple-net tows with 200 and 500 µm meshes were carried out at three depths (100, 200, and 400 m), and the samples were processed with ZooScan to classify organisms into eight taxonomic groups. Zooplankton distributions were analyzed for the surface layer (0–100 m), a mid-depth layer (100–200 m), and a deeper layer (200–400 m). The results did not show a significant increase in biomass in the front in any layers. The NBF appears to act as a boundary between communities rather than a pronounced area of active or passive zooplankton accumulation. Analyses of stratified vertical distributions of zooplankton highlighted distinct taxonomic compositions in the three layers, and a progressive homogenization of community structure with depth, reflecting a weaker impact of hydrological processes on deeper communities. The clearest impact of the front was within the upper 100 m, where the mesozooplanktonic taxonomic composition differed between the front and adjacent water masses, with a decrease in all taxonomic groups except Cnidaria, which increased dramatically. In the two deeper layers, the front also influenced community composition, although to a lesser extent, with marked increases in Foraminifera and Cnidaria. Moreover, the northern water mass and the front were dominated by large copepods, while the southern water mass exhibited higher zooplankton diversity and smaller-sized copepods. The results of this study highlight the complexity of processes shaping planktonic communities over time and space in the NBF zone and its adjacent waters. These processes include zooplankton stock reduction in the transitional post-bloom period, marked effect of diel variation linked to vertical migrations, and potentially the impact of storm-related mixing in the surface layer that can disrupt established ecological patterns