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Cross-border impacts of nuclear phase-out policies on the European power system: Economic and environmental insights for strategic energy planning
No full textInternational audienceThe European power system plays a strategic role in reducing dependence on fossil fuels while contributing to reaching Europe's CO2 emissions targets. The energy crisis triggered by Russia's war against Ukraine has revived interest in the role of nuclear energy in the European power system. We examine how postponing nuclear phaseout affects optimal dispatch and environmental performance of the interconnected European power system. We use ESMOD, a unit commitment model of the European electric system at the 2030 horizon, built with Antares Simulator, to assess the impact of nuclear phase-out policies in Germany and Belgium. The model accounts for 36 European countries and focuses on cross-border effects and country-level impacts. The model shows that not decommissioning 4 GW of nuclear capacity in these two countries would have reduced European CO2 emissions by 16 million tons in 2030. Strikingly, about 45% of such reductions would have occurred in other European countries and keeping nuclear power plants in operation would have increased the total European surplus by 3 billion euros heterogeneously affecting across countries. To interpret these heterogeneous effects, we analysed the load size, power mix, trader status and interconnections to explain cross-border sensitivities. Finally, we assessed the countries' sensitivity to weather variation across 34 climate years by classifying them using the Kmeans clustering method. The results underscore the central role of European energy policy coordination in shaping future energy strategies that prioritize climate goals and efficient system integration while challenging the economic efficiency and environmental effectiveness of solely national plans
Self-similar Markov trees and scaling limits
No full textInternational audienceSelf-similar Markov trees constitute a remarkable family of random compact real trees carrying a decoration function that is positive on the skeleton. As the terminology suggests, they are self-similar objects that further satisfy a Markov branching property. They are built from the combination of the recursive construction of real trees by gluing line segments with the seminal observation of Lamperti, which relates positive self-similar Markov processes and Levy processes via a time change. They carry natural length and harmonic measures, which can be used to perform explicit spinal decompositions. Self-similar Markov trees encompass a large variety of random real trees that have been studied over the last decades, such as the Brownian CRT, stable Levy trees, fragmentation trees, and growth-fragmentation trees. We establish general invariance principles for Galton--Watson trees with integer types and illustrate them with many combinatorial classes of random trees that have been studied in the literature
Bacterial and Fungal Communities in Old Vines and Their Progeny: Insights into Microbial Inheritance Through Mass Selection
No full textInternational audienceMass selection is increasingly promoted in viticulture to enhance resilience by restoring intra-varietal diversity, yet its effects on the structure and inheritance of plant-associated microbiomes remain poorly understood. Here, we investigated bacterial and fungal communities associated with old grapevine mother plants and their progeny across four Bordeaux estates practicing mass selection, using a fully in situ experimental design. Root and leaf microbiomes were characterized by metabarcoding and analyzed using multivariate ordination, hierarchical clustering, and assembly-process metrics (βNTI and NST). Microbial community composition and structure were primarily shaped by plant compartment and vineyard origin, whereas generation effects were significant but weak. Microbial resemblance between mother vines and their offspring was limited and highly context-dependent, occurring mainly under comparable environmental conditions. Assembly-process analyses revealed heterogeneous deterministic signals, particularly in root-associated bacterial communities, but did not consistently result in phylogenetic similarity between generations. Although inheritance signals were generally weak, their recurrence across multiple vineyards and contrasted field conditions highlights their ecological relevance. By integrating environmental variability, this in situ approach mitigates the adaptive bias in plant–microbiome interactions and shows that mass selection does not rely on systematic microbial transmission but rather operates within a nuanced framework of environmentally mediated interactions
Decoding the Integrated Stress Response of Pancreatic Cancer: Identifying a Serine‐dependent Tumor Subset Under Metabolic Relationships With CAFs.
No full textInternational audienceABSTRACT Pancreatic ductal adenocarcinoma (PDA) transcriptomic profiling has identified prognostic subtypes, yet patient‐specific first‐line therapies remain elusive. Here, we stratified PDA tumors by mRNA translation rates, a frequently dysregulated step in gene expression, using translatome profiling of 27 patient‐derived xenografts (PDXs). Unsupervised analysis revealed a distinct tumor subset with low global protein synthesis but sustained translation of Integrated Stress Response (ISR) mRNAs, including ATF4. These ISR‐activated cancer cells exhibited broad chemoresistance and apoptosis resistance, yet were auxotrophic for serine due to loss of PHGDH and CBS expression, impairing serine and cysteine biosynthesis. This vulnerability correlated with improved overall survival in patients with low expression of both enzymes. Notably, cancer‐associated fibroblasts (CAFs) reprogrammed by ISR‐activated cells, shifting from myCAF to iCAF phenotype with reduced collagen synthesis and glycine‐to‐serine conversion, produced serine and sustained tumor growth in amino acid‐depleted environments. Our findings demonstrate the power of translatome profiling to reveal stable, drug‐resistant PDA cell states and identify a targetable CAF‐tumor metabolic symbiosis, opening new avenues for therapeutic intervention in this highly lethal malignancy
OligoN-design: A simple and versatile tool to design specific probes and primers from large heterogeneous datasets
No full textAbstract High-throughput environmental DNA sequencing has ushered ecological and evolutionary studies into the big data era. With thousands to millions of DNA sequences, designing taxon-specific oligonucleotides is a current bottleneck of molecular studies that rely on primers for Polymerase Chain Reactions (PCRs) or probes for Fluorescence in situ Hybridization (FISH). No software currently exists to design specific oligonucleotides starting from a custom set of sequences. Existing tools rely on specific databases, alignments or phylogenetic trees, or cannot accommodate increasingly large molecular environmental datasets. Here we present oligoN-design, a versatile tool to design oligonucleotides specific to a set of target sequences while minimizing predicted binding to non-target sequences. OligoN-design is simple, reproducible, and adaptable to high-throughput sequencing data analyses. It requires only two fasta files as input, one containing target taxa and the other containing non-target taxa. Using standard bioinformatic formats, it integrates easily with other tools such as BLAST, VSEARCH or MAFFT. OligoN-design allows a range of strategies that we present in detail, from an unsupervised end-to-end usage all the way to a detailed and thorough expert usage. Starting with large, comprehensive ribosomal databases that are widely used by the community (i.e., PR2, SILVA) and the unsupervised function, we were able to replicate known taxa-specific oligonucleotides in under 30 minutes and up to 6 Gb of RAM on a personal laptop. OligoN-design v1, available at github.com/MiguelMSandin/oligoN-design under GNU General Public License version 3.0, is easily installed via bioconda bioconda.github.io/recipes/oligon-design/README.html
Modified Abelian Gauge Theories
No full textInternational audienceThe topological properties of field configurations in gauge theory contain important data about the (generalized) global symmetries of the theory as well as potential inconsistencies in the form of gauge anomalies. In this work we modify the topological classes of Abelian -form fields, generating new global variants of gauge theories. These modifications implement constraints directly on the classifying space of the gauge field and its cohomology classes via homotopy fiber construction. This general approach allows us to investigate the universal effects of the constraints on the conserved global charges encoded in gauge characteristic classes. We further demonstrate that this procedure generically leads to new topological sectors introducing additional global charges and anomalies in the modified gauge theories
Investigating the role of climate change in the 3 May 2025 Western Europe hailstorm using atmospheric analogues
No full textInternational audienceOn 3 May 2025, a severe hailstorm struck Paris and parts of western Europe, raising concerns about the influence of climate change. We analyze this event using ERA5 reanalysis and an analogue-based attribution framework. The synoptic setting involved a cut-off low and a surface cold front, occurring shortly after an early-season heatwave. We compare analogous patterns in past (1974–1999) and recent (1999–2024) climates to assess thermodynamic differences. Hail probability and size were estimated with two models: a logistic formulation based on convective available potential energy, wind shear, and convective precipitation, and a new model incorporating freezing-level height and 850 hPa temperature, designed for European hail environments. Both were calibrated with Ile-de-France observations and validated with independent data. Our findings show that present-day conditions favor higher hail probabilities and larger hailstones, suggesting anthropogenic warming has likely enhanced hailstorm intensity in the region
Multistage investigation into positive and negative consequences of greenwashing business practices. Implications for business strategies
No full textFNEGE 3, ABS 3International audienceGreenwashing, which involves false promises of environmental responsibility, has become a significant problem in an age where environmental issues are increasingly becoming more problematic. This paper delves into the effects of corporate greenwashing through multiphase research design and interpretative phenomenological analysis (IPA) approach to comprehend the lived experiences of employees working in the tourism and hospitality sector. Our qualitative study encompassed two rounds of data collection and followed the grounded theory approach to discern insights from the open‐ended essays using Gioia methodology. Taking support of the stakeholder theory and the signaling theory, this paper shows short‐term positive reputational effects of greenwashing when unexposed and the severe harm being caused when it is exposed. Furthermore, we report on how stakeholder perceptions and reactions differ between large and small organizations and conclude by proposing strategic recommendations to curb deceptive environmental claims. Our study not only advances theoretical comprehension by acknowledging the multifaceted nature of greenwashing consequences but also provides practical insights for businesses operating in this area to curb such fraudulent practices
Antibiotic Use and the Persistence of Biologic Therapies in Patients With Psoriasis
No full textInternational audienceImportance The long-term effectiveness of biologic therapies in psoriasis may decline over time. Gut microbiota alterations induced by antibiotics have been proposed as a potential mechanism impairing biologic persistence. Objective To evaluate the association between antibiotic exposure and the persistence of biologic therapies in patients with psoriasis. Design, Setting, and Participants This retrospective cohort study used data from the French National Health Insurance database between June 2011 and December 2022. Adults initiating a biologic therapy for psoriasis were included, excluding those with preexisting inflammatory bowel disease at baseline. Data were analyzed from January to September 2024. Exposures At baseline, antibiotics exposure was classified as none, 1, or 2 or more dispensations in the 6 months preceding the index date. During follow-up, time-dependent antibiotics exposure was defined as none, 1, or 2 or more antibiotics dispensations in the 6 months prior to each time of follow-up. Main Outcomes and Measures The primary outcome was discontinuation or switch of the initial biologic therapy. Exposure to antibiotics was assessed within 6 months prior to biologic initiation and during follow-up. A weighted Cox marginal structural model was used to estimate adjusted hazard ratios. Results Of 36 129 included patients, 11 228 (42.0%) were female, 20 192 (55.9%) were male, and the mean (SD) age was 48.4 (15.1) years. A total of 9366 (25.9%) were exposed to antibiotics at baseline and 21 900 (60.6%) during follow-up. The most commonly prescribed antibiotic classes were β-lactams, macrolides, and fluoroquinolones. Antibiotic exposure was associated with a higher risk of biologic discontinuation (weighted hazard ratio, 1.12; 95% CI, 1.08-1.16), with a stronger effect observed for multiple dispensations (weighted hazard ratio, 1.29; 95% CI, 1.24-1.35), suggesting a dose-response relationship. Conclusions and Relevance In this cohort study, antibiotic exposure was significantly associated with an increased risk of discontinuation of biologic therapies in psoriasis. These findings support the hypothesis that antibiotics, potentially through gut dysbiosis, may reduce biologic persistence. However, unmeasured confounders limit causal interpretation. Further studies are necessary to validate these findings
Combined Temperature and Photobleaching Effects on P‐Doped Optical Fibers
No full textInternational audienceIn this paper, we investigate the combined effects of temperature and photobleaching (PB) on multimode phosphorus‐doped (P‐doped) optical fibers (OFs) response under irradiation. To achieve this purpose, we investigate the kinetics of the radiation‐induced attenuation (RIA) in the visible spectral range (450–800 nm) under X‐ray irradiation up to 5Gy(SiO 2 ) with a dose rate of 10 mGy(SiO 2 )/s, varying the temperature of irradiation from −80°C to +80°C. This study is part of a recent series of investigations on the regeneration of these radiation‐sensitive optical fibers after they have served as dosimeters. The spectral range investigated allows us to study absorbing defects such as the metastable and stable phosphorus oxygen hole centers (POHC) and the P2 point defects. Our data suggests that thermally‐assisted bleaching has an impact during and after irradiation on the RIA. It is clear that thermal bleaching is relevant, especially for wavelengths below 580 nm; its contribution remains minor compared to that of the PB by 408 nm laser. Furthermore, thermal bleaching appears to be negligible for wavelengths above 580 nm. This work provides further understanding of the combined temperature and photobleaching effects on the regeneration of transmission capability of P‐doped fiber dosimeters in the visible range