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Théorème de la base normale effectif
No full textLet K be a finite Galois extension of Q. The normal basis theorem provides an element of K whose conjugates form a Q-basis of K. Here we obtain such an element with controlled size. This improves a recent result by Fukshansky and Jeong. By the way, we estimate Minkowski's minima of ideals of integers of number fields
A randomized phase III trial of structured tumour response surveillance and shared decision‐making for organ preservation in rectal cancer – PRODIGE 101‐ GRECCAR 20‐ EVAREC trial protocol
No full textInternational audienceAbstract Aim Standard management with chemoradiotherapy (CRT) or total neoadjuvant therapy (TNT) followed by total mesorectal excision (TME) reduces local recurrence but often is associated with significant long‐term functional impairment. Organ preservation (OP) has become a key therapeutic goal in rectal cancer to reduce surgery‐related morbidity without compromising oncological outcomes. Three main OP strategies have been developed: Watch and Wait (W&W) strategy, Local Excision (LE) and Contact X‐ray Brachytherapy (CXB), both applicable in patients showing a favourable tumour response after neoadjuvant therapy. The current challenge is defining the optimal timing and modalities for response assessment to accurately identify complete clinical response while balancing oncological control, functional outcomes and patient preferences. This trial evaluates whether a structured tumour response surveillance program combined with shared decision‐making (SDM) can safely increase OP rates. Methods GRECCAR 20 is a multicentre, randomized, open‐label, phase III trial enrolling patients with cT2‐T3N0‐1 rectal adenocarcinoma ≤ 8 cm from the anal verge and ≤ 4 cm in length, without involvement of the anal canal. Across the French GRECCAR and PRODIGE network, 270 patients will be recruited over 36 months. After neoadjuvant treatment (CRT or induction chemotherapy followed by CRT), participants are randomized to either a structured tumour response surveillance strategy with SDM over 8 to 24 weeks (experimental arm) or standard response assessment without SDM at 8 weeks (control arm). In the experimental arm (Arm A), reassessments at 2‐, 4‐ and 6‐month post‐treatment will guide management decisions—W&W, LE, CXB or TME—through a collaborative process between patient and clinician. In the control arm (Arm B), treatment decisions at 2 months will be made solely by the clinician, between LE or TME, based on clinical, endoscopic and radiological assessment. The primary outcome is the OP rate at 2 years. Secondary endpoints include disease‐free survival, TME‐free survival, functional outcomes, quality of life (QoL) and patient‐reported outcome measures (PROMs). Conclusion GRECCAR 20 is the first randomized trial to assess a structured tumour response surveillance program incorporating SDM in rectal cancer. By prioritizing patient values and QoL, this trial aims to improve OP rates without compromising oncological safety, potentially establishing a new standard of personalized, patient‐centred care
Characterisation of Markov property on planar maps
No full textWe revisit, in a self contained way, the Markov property on planar maps and decorated planar maps from three perspectives. First, we characterize the laws on these planar maps that satisfy both the Markov property and rerooting invariance, showing that they are Boltzmann-type maps. Second, we provide a comprehensive characterization of random submaps, that we call stopping maps, satisfying the Markov property, demonstrating that they are not restricted to those obtained through a peeling procedure. Third, we introduce decorated metric planar maps in which edges are replaced by copies of random length intervals [0,we], and the decorations are given by continuous functions on the edges. We define a probability measure on them that is the analogue of the Boltzmann map and show that it satisfies the Markov property even for sets that halt exploration mid-edge
On the complexity of the Maker-Breaker happy vertex game
No full textGiven a c-colored graph G, a vertex of G is happy if it has the same color as all its neighbors. The notion of happy vertices was introduced by Zhang and Li to compute the homophily of a graph. Eto, et al. introduced the Maker-Maker version of the Happy vertex game, where two players compete to claim more happy vertices than their opponent. We introduce here the Maker-Breaker happy vertex game: two players, Maker and Breaker, alternately color the vertices of a graph with their respective colors. Maker aims to maximize the number of happy vertices at the end, while Breaker aims to prevent her. This game is also a scoring version of the Maker-Breaker Domination game introduced by Duchene, et al. as a happy vertex corresponds exactly to a vertex that is not dominated in the domination game. Therefore, this game is a very natural game on graphs and can be studied within the scope of scoring positional games. We initiate here the complexity study of this game, by proving that computing its score is PSPACE-complete on trees, NP-hard on caterpillars, and polynomial on subdivided stars. Finally, we provide the exact value of the score on graphs of maximum degree 2, and we provide an FPT-algorithm to compute the score on graphs of bounded neighborhood diversity. An important contribution of the paper is that, to achieve our hardness results, we introduce a new type of incidence graph called the literal-clause incidence graph for 2-SAT formulas. We prove that QMAX 2-SAT remains PSPACE-complete even if this graph is acyclic, and that MAX 2-SAT remains NP-complete, even if this graph is acyclic and has maximum degree 2, i.e. is a union of paths. We demonstrate the importance of this contribution by proving that Incidence, the scoring positional game played on a graph is also PSPACE-complete when restricted to forests
Northernmost record in the Bay of Biscay (northeastern Atlantic) of two leptothecate hydroids (Cnidaria: Hydrozoa) of southern affinity
No full textInternational audienceTwo leptothecate hydroids of southern affinity, Sertularella ornata Broch, 1933 and Sertularelloides cylindritheca (Allman, 1888) were collected in the southern sector of the Bay of Biscay off Saint Jean de Luz (France). The latter was also seen during several ROV surveys on rocky communities along the Cantabrian Sea and northwestern Spain. Each of the two species is herein described and illustrated and their worldwide distribution, bathymetric ranges and reproductive periods, revised; additionally, we allocate them in their biocoenological context, providing in situ images. The northern boundary limits are extended for both hydroids, which are new records for the Atlantic coast of France; the latter belongs to a genus previously unrecorded in the French mainland fauna. We also discuss the importance of having inventories of the sessile fauna of the exceptional sites at study, for the sake of their protection and detection of future modifications due to climate change
Continuized Nesterov Acceleration for Non-Convex Optimization
No full textIn convex optimization, continuous-time counterparts have been a fruitful tool for analyzing momentum algorithms. Fewer such examples are available when the function to minimize is non-convex. In several cases, discrepancies arise between the existing discrete-time results -namely those obtained for momentum algorithms -and their continuous-time counterparts, with the latter typically yielding stronger guarantees. We argue that the continuized framework (Even et al., 2021), mixing continuous and discrete components, can tighten the gap between known continuous and discrete results. This framework relies on computations akin to standard Lyapunov analyses, from which are deduced convergence bounds for an algorithm that can be written as a Nesterov momentum algorithm with stochastic parameters. In this work, we extend the range of applicability of the continuized framework, e.g. by allowing it to handle non-smooth Lyapunov functions. We then strengthen its trajectory-wise guarantees for linear convergence rate, deriving finite time bounds with high probability and asymptotic almost sure bounds. We apply this framework to the non-convex class of strongly quasar-convex functions. Adapting continuous-time results that have weaker discrete equivalents to the continuized method, we improve by a constant factor the known convergence rate, and relax the existing assumptions on the set of minimizers
An all-Mach cell-centered multi-dimensional nite volume numerical scheme for the Euler equations
No full textInternational audienceIn the context of the numerical approximation of Euler equations, great efforts have been devoted to developing schemes that can accurately reproduce solutions in low Mach number ows. Solutions of classic Finite Volume (FV) schemes are usually plagued by an excessive diusion as the numerical scheme is not consistent with the limit equations for the Mach number that tends to zero. Instead, a numerical scheme that satises such a property is called Asymptotic-Preserving (AP). In this paper, we propose an AP FV scheme for the multi-dimensional Euler equations. In classic FV methods, the numerical approximation of the face ux is obtained by means of a two-state 1D approximate Riemann Solver (RS) in the normal direction to the face. Here, we rely on a node-based ux approximation that exploits a particular RS involving a nodal quantity which depends on all the cells around a given node. Such an idea has been exploited by Barsukow et al. (2023) for the linear acoustic equations. Their method is vorticity-preserving, but its extension to the Euler equations proved to be far from trivial. For such a reason, a change of perspective is needed in the denition of the RS
Genomics of Long-Term Complications of Childhood Leukemia: Rationale and Design of the GenLEA Study
No full textCited by: 0International audienceBackground: Survivors of childhood acute leukemia are at risk of long-term treatment-related complications, but the role of genetic susceptibility remains unclear. We describe here the GenLEA project, which was established to investigate genetic determinants of long-term complications. Methods: GenLEA builds on the French LEA cohort, which prospectively follows acute leukemia survivors since 2004 through standardized dedicated consultations every 2 to 4 years. Patients were selected from the nested CryoLEA biobank. Cases were defined as survivors with at least one of four major complications (anthracycline-related cardiomyopathy, secondary malignant neoplasms, metabolic syndrome, or osteonecrosis) while controls were survivors without these complications, selected with the objective of a 1:3 case-to-control ratio. Genetic data were generated using genome-wide genotyping and whole-exome sequencing. Results: After quality control, 743 patients were included for analyses (241 cases and 502 controls). Fifty-one percent were male with a median age at diagnosis of 7.3 years (IQR 3.9–13.0), and median follow-up reached 14 years (IQR 7.9–19.8). Among the cases, 44 had cardiomyopathy, 50 osteonecrosis, 37 secondary malignant neoplasms, and 163 metabolic syndrome. Planned analyses include genome-wide association studies (GWAS) and downstream analyses such as transcriptome-wide association studies (TWAS) and Mendelian randomization on genotyping data, as well as gene-based tests on exome sequencing data. Perspectives: By integrating these approaches with high-quality clinical information, GenLEA offers a unique opportunity to identify molecular determinants of late complications after childhood acute leukemia. This collaborative resource will support replication efforts, meta-analyses, and ultimately the development of personalized long-term follow-up strategies. © 2026 Wiley Periodicals LLC
Sauvage en ville : une approche socio-écologique des interactions entre humains et faune urbaine. Le cas des sangliers à Bordeaux
No full textInternational audienceHuman–wildlife interactions are a rapidly expanding field of research. This paper seeks to clarify three fundamental dimensions: co-presence, human–animal interactions, and interactions among humans regarding multiple animal categories. Focusing on the case of wild boar in urban environments, it develops a geographical perspective that combines animal geography and social geography centered on animals, giving equal attention to human and animal spatialities. Research on urban wild boar, conducted in Bordeaux and the Gironde region, was carried out in two consecutive phases. The first phase involved fundamental research (2018–2023), examining interfaces of co-presence, human–animal interactions, and human–human interactions concerning wildlife. A socio-ecosystem approach is used to articulate the dynamics of human and animal subsystems by analyzing their interactions, including the positive and negative impacts of wildlife on human societies and the management measures implemented to mitigate or enhance them. The second phase consists of an action-research project (2023–2026) aimed at improving management policies for liminal large fauna. The paper discusses the conditions for coexistence policies between humans and wildlife deliberately kept at a distance from human settlements, as well as between humans themselves. The approach highlights the importance of recognizing animal agency, that is, the capacity of animals to reshape complex socio-spatial dynamics at the very heart of cities.Les interactions entre humains et faune sauvage constituent un champ de recherche en plein essor. Ce texte propose de clarifier trois dimensions fondamentales : la coprésence, les interactions entre humains et animaux et les interactions entre humains à propos des multiples catégories d’animaux. A partir du cas du sanglier en ville est développée une lecture géographique croisant géographie de l’animal et géographie sociale autour de l’animal, avec une attention égale portée aux spatialités humaines et animales. La recherche sur le sanglier urbain, conduite sur les terrains bordelais et girondin, s’est déroulée en deux temps consécutifs. Le premier temps relève d’une recherche fondamentale (2018-2023). Les études portent sur l’interface de la coprésence, les interactions entre humains et animaux et celles entre humains à leur propos. L’approche par les socio-écosystèmes permet d’articuler les logiques propres aux sous-systèmes humains et animaux, en analysant leurs interactions : impacts positifs ou négatifs de la faune sur les sociétés humaines et dispositifs de gestion mis en œuvre pour les atténuer ou les valoriser. Le second temps consiste en une recherche-action (2023-2026) visant à améliorer les politiques de gestion de la grande faune liminaire. Le texte discute les conditions de politiques de cohabitation entre humains et une faune volontairement tenue à distance des habitats, comme entre humains eux-mêmes. L’approche souligne l’enjeu de la reconnaissance de l’agentivité animale, c’est-à-dire de la capacité de ces animaux à réagencer des dynamiques socio-spatiales complexes au cœur même des villes