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Bacterial chromatin remodeling associated with transcription-induced domains at pathogenicity Islands
No full textInternational audienceAbstract The nucleoid-associated protein H-NS is a bacterial xenogeneic silencer responsible for preventing costly expression of genes acquired through horizontal gene transfer. H-NS silences several Salmonella Pathogenicity Islands (SPIs) essential for host infection. The stochastic expression of SPI-1 is required for invasion of host epithelial cells but complicates investigation of factors involved in SPI-1 chromatin structure and regulation. We performed functional genomics on sorted Salmonella populations expressing SPI-1 or not, to characterize how SPI-1 activation affects chromatin composition, DNA conformation, gene expression and SPI-1 subcellular localization. We show that silent SPIs are associated with spurious antisense transcriptional activity originating from H-NS-free regions. Upon SPI-1 activation, remodeling of H-NS occupancy defines a new chromatin landscape, which together with the master SPI-1 regulator HilD, facilitates transcription of SPI-1 genes. SPI-1 activation promotes formation of Transcription Induced Domains accompanied by repositioning SPI-1 close to the nucleoid periphery. We present a model for tightly regulated chromatin remodeling that minimizes the cost of pathogenicity island activation
Articles de résultats, articles d’interprétations : des modes nouveaux de publication des résultats scientifiques
No full textInternational audienceDigital technology and the "open science" movement are revolutionizing scientific publishing. So called data papers offer an additional publication option, limited to methods and results, describing information deposited on dedicated websites: they would be more accurately called "results articles." However, their introduction leads to the idea of complementary theoretical articles that would contain only the interpretations, which are sometimes more time-consuming to produce.Le numérique et les mouvements de « science ouverte » bouleversent l'édition scientifique. Des « articles de données (data papers) sont une possibilité supplémentaire de publication, limitée à des méthodes et des résultats. Ils décrivent des informations préalablement déposées sur des sites à cet effet : ils seraient plus justement nommés « articles de résultats », mais, surtout, leur introduction conduit à imaginer des « articles théoriques », complémentaires, qui contiendraient seulement les interprétations, parfois plus longues à produire
Magnetic reversals in a geodynamo model with a stably–stratified layer
No full textInternational audienceWe study the process of magnetic reversals in the presence of a stably-stratified layer below the core-mantle boundary using direct numerical simulations of the incompressible magnetohydrodynamics equations under the Boussinesq approximation in a spherical shell. We show that the dipolar-multipolar transition shifts to larger Rayleigh numbers in the presence of a stably-stratified layer, and that the dipolar strength of the magnetic field at the core-mantle boundary increases due to the skin effect. By imposing an heterogeneous heat flux at the outer boundary, we break the equatorial symmetry of the flow, and show that different heat flux patterns can trigger different dynamo solutions, such as hemispheric dynamos and polarity reversals. Using kinematic dynamo simulations, we show that the stably-stratified layer leads to similar growth rates of the dipole and quadrupole components of the magnetic field, playing the role of a conducting boundary layer, favouring magnetic reversals, and a dynamics predicted by low-dimensional models
Integrating tagged neutron inspection with explainable AI for threat material identification
No full textInternational audienceHere we present an innovative approach for identifying threat materials within a sealed container by inspecting it through integrating tagged fast neutron activation analysis and Explainable Artificial Intelligence (XAI). Two AI models, a Feed-Forward Neural Network (FFNN) and a Convolutional Neural Network (CNN), were developed to analyze the emitted gamma rays to identify materials like explosives and drugs based on depth profiles of carbon, nitrogen, and oxygen concentrations. XAI was applied to make the models' decision-making process transparent. The method is adaptable to various spectrometric analyses. We demonstrate its effectiveness using data obtained by the Rapidly Relocatable Tagged Neutron Inspection System (RRTNIS), which is irreplaceable for inspecting sealed cargo containers, despite challenges such as variable material placement, background noise, and shielding effects. Our approach successfully locates and categorizes threat materials, both alone and within surrounding materials, at various locations within sealed cargo containers
Who decides? Positioning stakeholders in a decision-making process via network modeling and analysis: Application to regional trains decarbonization
No full textInternational audienceUnderstanding and controlling stakeholder influence in public–private decision-making remains a significant challenge for public authorities. This study proposes a methodology for diagnosing, modeling, and reorganizing stakeholder contributions within complex decision-making processes. The methodology integrates five steps: stakeholder identification, stakeholder network modeling, network analysis, stakeholder clustering, and a reorganization phase that aligns stakeholder involvement with the specific objectives of each decision stage. The methodology is applied to public-private network data to reveal influence patterns, dominant actors, and structural coalitions. Stakeholders are identified, and their interactions are formalized using a weighted Design Structure Matrix (DSM). Network indicators are computed to characterize interaction intensity and connectivity. Clustering algorithms are applied to identify clusters of closely interacting stakeholders, which serve as the basis for reorganizing stakeholder involvement across decision stages. We applied the methodology to the decarbonization of French regional diesel trains. Data were collected through interviews conducted with multiple regional transport authorities. The results show an intense concentration of decisional weight among industrial stakeholders and higher-level public institutions, indicating governance vulnerabilities stemming from asymmetric access to information and influence. A validation phase was conducted with a regional decision-maker (Corse), confirming the practical relevance of the proposed stakeholder reorganization and supporting its applicability to real-world decision processes. The study demonstrates that dynamically structuring stakeholder involvement can mitigate risks, enhance decision robustness, and assist public authorities in managing private-sector influence. While illustrated through a specific case study, the methodology is generalizable to any multi-actor public–private decision-making context
Decentralized Coalition Formation of Infrastructure Providers for Resource Provisioning in Coverage Constrained Virtualized Mobile Networks
No full textInternational audienceThe concept of wireless virtualized networks allowsthe utilization of resources provided by several infrastructureproviders (InP) to set up a service over some geographical area.Resource provisioning in such situation is challenging due tothe reluctance of InPs to share private information. This paperproposes a decentralized solution allowing several InPs to forma coalition so as to satisfy the constraints imposed by a MobileVitrual Network Operator, while sharing limited information.The proposed solution adopts a hedonic approach for coalitionformation. The coalition decisions relies on satisfaction of servicerequirements and on the profit of InPs. The evaluation resultdemonstrates the applicability and performance of the proposedsolution
ALTOPANC: Local ablative therapies in oligometastatic pancreatic adenocarcinoma—A bi-national French-Belgian retrospective study.
No full textInternational audienceBackground: Oligometastatic disease (OMD) in pancreatic ductal adenocarcinoma (PDAC) is an emerging clinical entity. The limited extension of the disease prompt to explore the role of metastases-directed therapies (MDT); however, their actual survival and clinical benefits remain uncertain. Additional studies with larger effectives are needed to clarify the role of MDT in clinical practice. Methods: We conducted a retrospective multicenter, observational French-Belgian study to evaluate the impact of MDT on event-free survival (EFS) and overall survival (OS) in patients with OMD-PDAC. OMD was defined as metastases (mets) involving no more than 2 organ and ≤5 mets (Leonhardt CS. ESMO Open 2023). Eligible patients were adults with histologically confirmed PDAC who underwent a resection of the primary tumor, with concurrent or subsequent MDT of MDT. OS was defined as the delay from MDT to death from any cause; EFS was calculated from the date of MDT until radiologically confirmed disease progression, recurrence or death. The ALTOPANC score—based on known prognostic factors (CA 19-9 >90 U/mL, > 1 met, and non-pulmonary mets)—was correlated with OS and EFS. Results: Between 01/2011 and 12/2024, 155 patients with OMD-PDAC were included; 138 had metachronous metastases. Sites of mets included liver (n=71, 45%), lung (n=61, 39%), periaortic lymph nodes (n=13, 8%) and peritoneum (n=5, 3%). At time of the met's diagnosis, 107 patients (71%) had a single met, and 25 (17%) patients had presented two mets. After a median follow-up of 4.42 years, median EFS and median OS in the entire population were of 0.8 and 3,4 years respectively. MDT modalities consisted in surgery (n=69, 45%), radiotherapy (n=50, 32%), and thermoablation (n=36, 23%). In the multivariate Cox model, higher CA 19-9 level (HR = 1.29, 95% CI: 1.13–1.48, p = 0.0002) and the presence of 2 (HR = 2.54, 95% CI: 1.32–4.88, p <0.0001) or ≥3 treated mets (HR = 4.39, 95% CI: 2.18–8.84, p <0.0001) were independent adverse prognostic factors for OS. Thermoablation was independently associated with an improved OS compared to other technics (HR=0.51, 95%CI: 0.27–0.96, p =0.0127). The ALTOPANC score was significantly associated with EFS :2-year EFS rates were 53.1%, 23.8%, 8.3%, and 0% in patients with scores of 0, 1, 2, and 3, respectively (p < 0.001). A similar trend was observed for OS. Conclusions: 1) This real-world, study shows promising results of MDT in patients with OMD-PDAC, particularly thermoablation ; 2) among patients with favorable prognostic profile (low ALTOPANC score) may have the higher benefit. A prospective randomized study is warranted to confirm these results
Women, menopause, hormone therapy, and cardiovascular disease: what WHI still teaches us in 2025, and where are we now?
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Communication as a core non-technical skill in pediatric surgery: existing frameworks and potential implementation in training programs
No full textInternational audiencePurpose :Communication skills are essential non-technical competencies in pediatric surgery, yet formal training programs remain limited and inconsistent. This perspective article examines the critical role of communication across pediatric surgical subspecialties and proposes frameworks for implementing structured communication training in residency programs.Methods :We performed a narrative review of published literature on communication skills in pediatric surgery and synthesized existing communication frameworks applicable to surgical training. Expert perspectives were gathered from an international group of pediatric surgeons representing diverse subspecialties including prenatal counseling, neonatal surgery, pediatric urology, and pediatric surgical oncology.Results :We identify specific communication challenges unique to pediatric surgery, including prenatal counseling, neonatal intensive care discussions, sensitive urological conditions, and pediatric oncology. Existing frameworks such as SPIKES for delivering bad news and EMPATHY for non-verbal communication provide evidence-based tools adaptable to pediatric contexts. Current training approaches remain largely informal and mentor-dependent, with significant variability between programs.Conclusion :Pediatric surgery training programs should integrate structured communication curricula with defined learning objectives, simulation-based practice, and regular feedback mechanisms to prepare trainees for the unique communication demands of caring for children and their families
Balanoposthitis due to Klebsiella aerogenes in men who have sex with men
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