Archives ouvertes de Paris-Saclay
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Programmable wave-domain computing in wireless communications
No full textFuture wireless networks must achieve large gains in data rate, energy efficiency and latency while integrating sensing and computation. Programmable wave-domain computing (pWDC), which processes signals directly through reconfigurable wavematter interactions, offers a way to offload part of this burden from electronic processors. In this Perspective, we review historical roots and recent work on pWDC and discuss its promise and challenges. We focus on three challenges: prototype-aware runtime optimization of pWDC hardware, enriching functionalities beyond linear continuouswave operation, and integrating pWDC into network-level resource management. Finally, we outline open questions regarding expressivity, practicality, and security that will arise in the transition of pWDC to real-life deployment in future wireless infrastructures
Genome-wide association study of event-free survival in follicular lymphoma patients treated with front-line immunochemotherapy
No full textInternational audienceGenome-wide association studies (GWAS) have identified germline genetic variants for follicular lymphoma (FL) susceptibility. We conducted a GWAS of prognosis in FL patients to identify genetic predictors of event-free survival (EFS) as well as failure within the first 24 months after treatment initiation (EFS24) using patients treated with rituximab-based immunochemotherapy from 3 clinical trials and one prospective observational study (N=1,054). Statistical approaches consisted of a pooled GWAS of the four cohorts and a leave-one-cohort-out (LOCO) strategy to identify robust findings that replicated across the four cohorts. The top SNPs for EFS and EFS24 were marked by rs72625024 at 3q27.3 near FETUB and HRG (P=9.37x10 -8 ) and rs114695031 at 14q32.13 near TCL6 (P=1.93x10 -8 ), respectively. These two loci, which were discovered and validated in all 4 LOCO rounds, map near long-non-coding RNAs with putative tumor suppressor functions. Our results pinpoint potential novel biology and a contribution of host genetics to prognosis in FL
How many steps to reach steady state of postural stability, progression velocity and step length during gait initiation? Effects of ageing and Parkinson’s disease
No full textInternational audienceIntroduction:This study examined how many steps are required to reach a steady state of postural stability, progression velocity, and step length during gait initiation in healthy young adults, healthy elderly adults, and patients with Parkinson's disease (PD). Methods: Healthy young adults (n = 10), healthy elderly adults (n = 11), and PD patients (n = 12) had to initiate gait and walk straight at spontaneous and maximal velocity to the end of an 11-m long room. Mean values and variability of biomechanical indicators of postural stability ("margin of stability" [MoS], "braking index" [BI]), progression velocity (peak anteroposterior centre-ofmass velocity), and step length were computed along five successive steps using a markerless motion capture system. Results: The results showed that the number of steps required to reach steady state walking depended on the experimental variable. For the progression velocity, the step length and the BI, two steps were required. For the MoS, one step was required. PD patients and healthy participants used different strategies to reach steady state of BI, which may expose the former to a high risk of instability in the first step. Interestingly, mean BI and variability of PD patients returned to normal following this first step. Conclusion: These findings suggest that rehabilitation programs aiming to improve walking in PD patients at an early stage of the disease (stage 2 on the Hoen and Year scale) may specifically target the first step.</div
Predictability of North Pacific blocking events: Analogue‐based analysis of historical MIROC6 simulations
No full textInternational audienceAtmospheric blocking exerts a profound influence on midlatitude circulation, yet its predictability remains elusive, due to intrinsic nonlinearities and sensitivity to initial conditions. While blocking dynamics have been extensively studied, the impact of geographical positioning on predictability remains largely unexplored. This study provides a comparative assessment of the predictability of western and eastern North Pacific blocking events, leveraging analogue‐based diagnostics applied to Coupled Model Intercomparison Project Phase 6 (CMIP6) Model for Interdisciplinary Research on Climate, version 6 (MIROC6) simulations. Blocking structures are identified using geopotential height gradient reversal, with their temporal evolution analyzed through trajectory tracking and error growth metrics. Results reveal that eastern blocks exhibit lower predictability, characterized by rapid error divergence and increased mean logarithmic growth rates compared with western blocks. Persistence analysis gives no significant difference between eastern and western North Pacific blocking events. Sensitivity analyses across varying detection thresholds validate the robustness of these findings
Stabilization of a Wave-Heat Cascade System
No full textWe consider the output-feedback stabilization of a one-dimensional cascade coupling a reaction-diffusion equation and a wave equation through an internal term, with Neumann boundary control acting at the wave endpoint. Two measurements are available: the wave velocity at the controlled boundary and a temperature-type observation of the reaction-diffusion component, either distributed or pointwise. Under explicit, necessary and sufficient conditions on the coupling and observation profiles, we show that the generator of the open-loop system is a Riesz-spectral operator. Exploiting this structure, we design a finite-dimensional dynamic output-feedback law, based on a finite number of parabolic modes, which achieves arbitrary exponential decay in both the natural energy space and a stronger parabolic norm. The construction relies on a spectral reduction and a Lyapunov argument in Riesz bases. We also extend the design to pointwise temperature or heat-flux measurements
On the importance of Ni–Au–Ga interdiffusion in the formation of a Ni–Au/p-GaN ohmic contact
No full textInternational audienceHigh-resolution transmission electron microscopy (TEM) coupled to energy dispersive X-ray spectroscopy (EDX) is used to clarify the exact role of Ni-Au-Ga interdiffusion mechanisms taking place during rapid thermal annealing under an oxygen atmosphere of a Ni-Au/p-GaN contact. It is shown that oxygen-assisted, Ni diffusion to the top surface of the metallic contact through the formation of a nickel oxide (NiO x ) is accompanied by Au diffusion down to the GaN surface and by Ga out-diffusion through the GaN/metal interface. Electrical characterizations of the contact by a transmission line method show that an ohmic contact is obtained as soon as a thin, Au-Ga interfacial layer is formed, even after complete diffusion of Ni or NiO x to the top surface of the contact. Our results clarify that the presence of Ni or NiO x at the interface is not the main origin of the ohmic-like behavior in such contacts. Auto-cleaning of the interface during the interdiffusion process may play a role, but TEM-EDX analysis evidences that the creation of Ga vacancies associated with the formation of a Ga-Au interfacial layer is crucial for reducing the Schottky barrier height and maximizing the amount of current flowing through the contact
A coordinated haptic mechanism ensures efficient DNA sampling by the 8-oxoguanine glycosylase OGG1
No full textInternational audience7,8-Dihydro-8-oxoguanine (8-oxoG), a frequent mutagenic base modification occurring upon oxidative stress, is handled by the DNA glycosylase OGG1 when paired with cytosine, initiating the base excision repair pathway. Since 8-oxoG neither significantly impacts the DNA structure nor blocks transcription and replication, its detection requires a careful inspection of each base pair by OGG1. By monitoring this lesion search process in vitro and in living cells, we uncover a tight coordination between several conserved amino acids encircling the DNA. More specifically, we show that the N149–151 motif, on the target strand, as well as residues R154 and R204, on the opposite strand, both regulate OGG1 engagement on the DNA to ensure fast Y203-mediated base unstacking, a prerequisite for efficient 8-oxoG detection. These findings highlight the mechanisms that enable OGG1 to maintain rapid DNA sampling kinetics while preserving specificity for 8-oxoG in the context of the chromatin architecture within the nucleus
Maurice Kleman et la physique des défauts. Une approche topologique toujours d’actualité
No full textInternational audienceLes défauts sont au coeur de l'oeuvre que nous a léguée Maurice Kleman. Il s’agit ici, au-delà des dislocations (voir glossaire) bien connues pour leur rôle dans la plasticité des solides, de défauts dans des organisations très diverses de la matière telles que les textures ferromagnétiques, les cristaux liquides, les phases lamellaires et les quasi-cristaux. De par sa généralité, l’approche topologique de Maurice Kleman a profondément renouvelé la physique des défauts dans de nombreux domaines de la matière condensée
Ouvrir l’IA : entre exigences juridiques, souveraineté scientifique et politiques de diffusion
No full textInternational audienceIntervention sur le thème de "Ouvrir l’IA : entre exigences juridiques, souveraineté scientifique et politiques de diffusion "Objet et thématiques des journéesLes politiques de science ouverte ont sensibilisé et accompagné les acteurs de la recherche, financé des projets ou des infrastructures existantes, contribué au renforcement ou au développement de services, pour faciliter le changement vers une science plus ouverte.L’ambition de ces journées est de montrer l’impact de ces politiques et des initiatives qui en découlent. Cet impact pourra être observé dans les pratiques des chercheurs, dans les rôles et les compétences des personnels d’appui à la recherche ainsi que dans les résultats scientifiques. A travers des communications, des retours d’expérience ou encore des ateliers, venez observer la science en train de s’ouvrir !L’Université de Lorraine, Inria, INRAE et le CNRS, avec le soutien du Ministère de l'Enseignement Supérieur, de la Recherche et de l'Espace, organisent à Nancy, du 27 au 29 janvier 2026, des journées consacrées à l’impact des politiques en faveur de la science ouverte sur les pratiques et les résultats scientifiques