HAL Université de Toulouse, et Toulouse INP
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E4F1 coordinates pyruvate metabolism and the activity of the elongator complex to ensure translation fidelity during brain development
No full textInternational audiencePyruvate metabolism defects lead to severe neuropathies such as the Leigh syndrome (LS) but the molecular mechanisms underlying neuronal cell death remain poorly understood. Here, we unravel a connection between pyruvate metabolism and the regulation of the epitranscriptome that plays an essential role during brain development. Using genetically engineered mouse model and primary neuronal cells, we identify the transcription factor E4F1 as a key coordinator of AcetylCoenzyme A (AcCoA) production by the pyruvate dehydrogenase complex (PDC) and its utilization as an essential co-factor by the Elongator complex to acetylate tRNAs at the wobble position uridine 34 (U 34 ). E4F1-mediated direct transcriptional regulation of Dlat and Elp3, two genes encoding key subunits of the PDC and of the Elongator complex, respectively, ensures proper translation fidelity and cell survival in the central nervous system (CNS) during mouse embryonic development. Furthermore, analysis of PDH-deficient cells highlight a crosstalk linking the PDC to ELP3 expression that is perturbed in LS patients
On the accuracy of numerical methods for the discretization of anisotropic elliptic problems
No full textInternational audienc
Foreshock Ultralow Frequency Waves at Mars: Consequence on the Particle Acceleration Mechanisms at the Martian Bow Shock
No full textInternational audienceUsing Mars Atmosphere and Volatile EvolutioN Magnetometer observations, we report the first statistical study of ultralow frequency (ULF) waves at the Martian foreshock. The analyzed foreshock ULF wave events are observed in the 0.008-0.086 Hz frequency range, with nearly circular and elliptical left-handed polarization in the spacecraft reference frame. These waves are propagated quasi-parallel to the ambient magnetic field, with a moderate wave amplitude. All these properties are consistent with fast magnetosonic waves, most likely generated through the ion-ion right-hand resonant instability. In addition, our results suggest that the associated resonant backstreaming protons' velocities parallel to the mean magnetic field in the solar wind reference frame are 1.33 ± 0.40 times the solar wind velocity. The similarity between our results and previous reports at other foreshocks may indicate the presence of a common acceleration process acting in planetary bow shocks and that is responsible for this particular backstreaming population.</div
Acceptability and implementation potential of colorectal cancer screening and health literacy training: A qualitative study among general practitioners in deprived areas
No full textInternational audienceBackgroundColorectal cancer (CRC) is a significant contributor to cancer-related burden, ranking second in cancer mortality in France. Despite the proven survival benefits of systematic CRC screening, uptake remains suboptimal, particularly among people with limited health literacy (HL) and lower socioeconomic position. This study aimed to assess the acceptability of an e-learning training programme on HL and CRC screening among general practitioners (GPs) in deprived areas while also exploring strategies for its promotion and scale-up. MethodsA qualitative study nested within the DECODE cluster-randomised controlled trial (NCT04631692) across four French regions was conducted. Semi-structured interviews (phone or online) were carried out to capture opinions, experiences, and recommendations of GPs in the intervention arm. Thematic analysis, employing manual and NVivo coding, was performed.ResultsThe majority of 22 GPs (16/22) found the training acceptable, informative, tailored to their knowledge needs and offering great flexibility of use. The module on HL garnered more interest than the one on CRC screening, as it addressed a relatively new area for many GPs. It facilitated reflection on patient communication techniques and identified areas for improvement in physician-patient interaction. A perceived gap in the training was the insufficient interactivity in both didactic and virtual group sessions. ConclusionThe findings of this study show high acceptability of the e-learning training by participants, indicating a potential for implementation, if kept concise, self-paced, asynchronous, and with a stronger focus on HL. The training helped GPs reflect on their practices, enhance HL knowledge, and improve patient communication strategies, leading some to adopt new techniques in daily interactions with low HL patients, beyond just screening
Artemisinin pressure in field isolates can select highly resistant Plasmodium falciparum parasites with unconventional phenotype and no K13 mutation
No full textInternational audienceArtemisinin resistance, which poses a serious threat to malaria control efforts, is monitored in the field by delayed parasite clearance in patients, elevated parasite survival rate in the ring-stage survival assay, and mutations in the Plasmodium falciparum kelch13 gene. However, sporadic cases of artemisinin-resistant malaria do not meet all of these criteria, highlighting that our understanding of artemisinin resistance is still incomplete. Here, we selected for artemisinin resistance in vitro in nine P. falciparum field isolates from Africa, Asia, and South America. Artemisinin pressure selected highly resistant parasites in all lineages, but only one acquired a validated pfkelch13 mutation. Phenotypic tests evidenced an unconventional response of selected parasites that can be artemisinin-resistant only at an advanced ring age, making them undetectable by the standard “0–3 h” test used to monitor resistance. These results highlight the need for broader approaches to artemisinin resistance monitoring
Designing and disseminating organisational innovations. What commitments should stakeholders in agricultural and food systems make?
No full textThis issue deals with organizational innovations for the agroecological transition and sustainable agri-food systems, which took place in March 2024 at VetAgro Sup in Lempdes.International audienceDesigning and disseminating organizational innovations. What commitments should stakeholders in agricultural and food systems make? Some organizational innovations are a decisive lever for the agro-ecological transition. Many organisations are involved in these innovations, from agricultural professionals, public authorities, higher education and research, to the private sector. How are these different organizations acting in this direction? What convergences can be observed, and what controversies sometimes arise, on these uncharted paths towards more resilient forms of agriculture that are better integrated into society
Multiple objective linear programming over the probability simplex
No full textThis paper considers the problem of maximizing multiple linear functions over the probability simplex. A classification of feasible points is indicated. A necessary and sufficient condition for a member of each class to be an efficient solution is stated. This characterization yields a computational procedure for ascertaining whether a feasible point is efficient. The procedure does not require that candidates for efficiency be extreme points. An illustration of the procedure is offered
Characterization of the set of zero-noise limits measures of perturbed cellular automata
No full text33 pages, 7 figuresWe add small random perturbations to a cellular automaton and consider the one-parameter family (F_\epsilon)_{\epsilon>0} parameterized by where \epsilon>0 is the level of noise. The objective of the article is to study the set of limiting invariant distributions as tends to zero denoted . Some topological obstructions appear, is compact and connected, as well as combinatorial obstructions as the set of cellular automata is countable: is -computable in general and -computable if it is uniformly approached. Reciprocally, for any set of probability measures which is compact, connected and -computable, we construct a cellular automaton whose perturbations by an uniform noise admit as the zero-noise limits measure and this set is uniformly approached. To finish, we study how the set of limiting invariant measures can depend on a bias in the noise. We construct a cellular automaton which realizes any connected compact set (without computable constraints) if the bias is changed for an arbitrary small value. In some sense this cellular automaton is very unstable with respect to the noise
Achat public responsable en restauration collective et transition agroécologique: Quelles voies de progression ?
No full textAujourd'hui, plus que jamais, il est nécessaire de repenser notre approche des politiques alimentaires et agricoles afin de promouvoir la transition d’une agricultureconventionnelle à un système plus diversifié et sans doute d’inspiration agro-écologique. Dans cette optique, les collectivités territoriales, qui ne disposent pas d’une compétence spécifique en matière d'alimentation, aspirent à utiliser la restauration collective comme un levier pour la transition agroécologique. Cependant, pour leurs achats de denrées alimentaires, elles sont soumises aux exigences rigoureuses du droit de la commande publique.En s’appuyant sur les ressources de droit de la commande publique et de droit européen de la concurrence, l'objectif de ce travail a été de mieux comprendre le rôle que peut jouer un achat public responsable en restauration collective sur la transition agroécologique. Cette étude s’appuie sur l’hypothèse que la structuration d’une démarche d’achat responsable en restauration collective dépend à la fois du droit et de la manière dont sont appréhendées ces règles de droit par les acteurs concernés, ainsi que des ressources et moyens activables.Il ne s’agit pas tant de déterminer si l’achat public en restauration collective intègre ou non des considérations environnementales mais de comprendre comment il est possible de responsabiliser l’achat public dans ce secteur afin de soutenir la transition de nos systèmes agroalimentaires vers plus de durabilité, une transition qualifiée d’agroécologique. L’achat public est encadré par des règles strictes, fortement influencées par le droit européen de la concurrence. C’est parce que l’achat public est soumis à un cadre juridique très formel que les acheteurs doivent faire preuve d’ingéniosité pour promouvoir la transition agroécologique au travers de ce levier.Comprendre comment les acteurs agissent est aussi essentiel pour comprendre comment le droit peut évoluer afin de renforcer le rôle du droit dans le processus de transition vers l’agroécologie
CHEX-MATE: Dynamical masses for a sample of 101 Planck Sunyaev-Zeldovich-selected galaxy clusters
No full textInternational audienceThe Cluster HEritage project with XMM-Newton – Mass Assembly and Thermodynamics at the Endpoint of structure formation (CHEX-MATE) is a programme to study a minimally biased sample of 118 galaxy clusters detected by Planck through the Sunyaev–Zeldovich effect. Accurate and precise mass measurements are required to exploit CHEX-MATE as an astrophysical laboratory and a calibration sample for cosmological probes in the era of large surveys. We measured masses based on the galaxy dynamics, which are highly complementary to weak-lensing or X-ray estimates. We analysed the sample with a uniform pipeline that is stable both for poorly sampled or rich clusters –using spectroscopic redshifts from public (NED, SDSS, and DESI) or private archives and dedicated observational programmes. We modelled the halo mass density and the anisotropy profile. Membership is confirmed with a cleaning procedure in phase space. We derived masses from measured velocity dispersions under the assumed model. We measured dynamical masses for 101 CHEX-MATE clusters with at least ten confirmed members within the virial radius r 200c . Estimated redshifts and velocity dispersions agree with literature values when available. Validation with weak-lensing masses shows agreement within 8 ± 16 (stat.) ± 5 (sys.)%, and confirms dynamical masses as an unbiased proxy. Comparison with Planck masses shows them to be biased low by 34 ± 3 (stat.) ± 5 (sys.)%. A follow-up spectroscopic campaign is underway to cover the full CHEX-MATE sample