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Uncertainty principle for solutions of the Schrödinger equation on the Heisenberg group
No full textInternational audienceThe aim of this paper is two prove two versions of the Dynamical Uncertainty Principlefor the Schr\"odinger equation , where is the sub-Laplacian on the Heisenberg group.We show two results of this type. For the first one, the potential , we establish a dynamical version of Amrein-Berthier-Benedicks's Uncertainty Principle that shows that if and have both small support then . For the second result, we add some potential to the equation and we obtain a dynamical version of the Paley-Wiener Theorem in the spirit of the result of Kenig, Ponce, Vega \cite{KPV}. Both results are obtained by suitably transfering results from the Euclidean setting.We also establish some limitations to Dynamical Uncertainty Principles
Sex-specific DNA methylation marks associated with sex-biased risk of recurrence in unprovoked venous thromboembolism
No full textInternational audienceBACKGROUND: Whether to stop oral anticoagulants after a first unprovoked venous thromboembolism (VTE) is challenging, partially due to an intriguingly higher risk of VTE recurrence (rVTE) in men after therapy discontinuation. DNA methylation (DNAm) differences between men and women might underly this sex-biased rVTE risk difference. AIM: To investigate sex-specific associations between DNAm at cytosine-phosphate-guanine (CpG) sites and rVTE. METHODS: In 417 unprovoked VTE patients, including 101 experiencing recurrences over 5-year follow-up (REVERSE I), we analyzed blood DNAm using the Illumina EPIC array and performed a sex-stratified epigenome-wide association study. We further examined 181 major provoked VTE patients, including 36 recurrences over 14-year follow-up (MARTHA), to investigate whether DNAm are risk factors for rVTE after anticoagulation therapy. RESULTS: Hypomethylated CpGs at genes TBC1D22B-cg01060850 and ZHX2-cg07808424 in men and DIP2B-ch.12.1038646R and DENND3-cg03401656 in women were associated with rVTE at genome-wide level (p<7e-8). Though not statistically significant, DENND3-cg03401656 had the same direction of effect in MARTHA women. Sensitivity analysis confirmed the robustness of the estimates including potential confounders, adaptations of the Cox model, non-Europeans, and proximal methylation quantitative trait loci (meQTLs) in the association. The associated CpGs were situated at genes for membrane trafficking, corroborating the participation of Rab regulatory proteins in rVTE, and transcription factors. CONCLUSIONS: We identified DNAm marks as potential risk factors for sex-biased recurrence in unprovoked VTE. Further replication and experimental validation could refine our understanding on the regulation of the identified DNAm sites and help optimize personalized decision-making for long-term anticoagulation after first VTE
Maternal Prepregnancy Obesity and Offspring Intelligence Quotient at 5 Years: A Multicohort Analysis
No full textInternational audienceBackground: The relationship between maternal obesity and childhood cognitive development remains unclear. Prior studies did not adjust for important confounders, and preterm infants are a developmentally distinct group that remains scarcely examined. Objectives: To determine whether maternal prepregnancy body mass index (BMI) is associated with offspring intelligence quotient (IQ) up to 5 years and whether this relationship varies with gestational age. Methods: Data from two French birth cohorts, EDEN (all gestational ages) and EPIPAGE-2 (preterm children born between 24 and 34 weeks of gestation), were used for this study. Maternal prepregnancy weight and height were used to calculate prepregnancy BMI. The Wechsler Preschool and Primary Scale of Intelligence was used to assess child IQ around 5 years. Multivariable models were adjusted for confounders, including socioeconomic status and paternal BMI. Results: Analytical cohorts included 1100 children from EDEN and 2629 from EPIPAGE-2. Lower intellectual functioning (full-scale IQ < 85) was observed in 8.1% of children in EDEN and 19.6% in EPIPAGE-2. The prevalence of maternal obesity was 13.6% (EDEN) and 21.3% (EPIPAGE-2) among children with lower intellectual functioning compared to 8.9% (EDEN) and 12.9% (EPIPAGE-2) among children with normal intellectual functioning. Maternal prepregnancy obesity was associated with an approximately 3-point decrease in full-scale IQ scores in fully adjusted models (adjusted beta -2.8, 95% confidence interval [CI] -5.6, -0.1 and -2.6, 95% CI -4.7, -0.6 in EDEN and EPIPAGE-2, respectively). In EDEN, maternal obesity was associated with lower scores in the verbal IQ domain. Among infants born preterm (EPIPAGE-2), maternal obesity was associated with lower scores in the processing, reasoning, and verbal IQ domains. Adjustment for paternal BMI did not change the magnitude of the relationship with maternal obesity. Conclusions: High maternal prepregnancy BMI is associated with child cognitive development around 5 years of age
Etude de publics de l'Empreinte, Scène nationale Brive-Tulle (2024)
No full textSynthèse de l'étude de publics de l'Empreinte, Scène nationale Brive-Tulle menée de septembre à octobre 2024 par questionnaire auprès de 578 personnes déjà venues.</div
Comparaison de deux techniques d’élongation coronaire : une revue systématique de la littérature
No full textCrown lengthening is a surgical procedure aimed at improving periodontal health, increasing healthy tooth surface for prosthetic rehabilitation, and achieving aesthetic objectives, such as correcting a gummy smile, particularly in the anterior region. This technique was introduced many years ago and is considered quite predictable. However, it remains relatively invasive, as it often requires the elevation of a full-thickness flap to access the bone. While improvements have been proposed for gingivectomy (e.g., laser or electrosurgical techniques), the osteotomy procedure remains invasive in the conventional method. A more recent approach involves performing osteotomy without raising a surgical flap, referred to as a “closed” or “flapless” technique. This innovation has raised questions about its effectiveness compared to the conventional technique. This study explores the evolution of crown lengthening techniques, focusing particularly on the flapless approach performed using sonic instruments. A comparison between the conventional and flapless methods is also discussed, providing insights into the future of this less invasive intervention.L’élongation coronaire est une intervention chirurgicale visant à améliorer la santé parodontale, à augmenter la surface dentaire saine pour des réhabilitations prothétiques et à répondre à des objectifs esthétiques, comme corriger un sourire gingival, notamment dans le secteur antérieur. C’est une technique introduite il y a de nombreuses années maintenant et qui est assez prédictible. C’est une technique relativement mutilante cependant puisque que bien souvent elle implique la levée d’un lambeau de pleine épaisseur pour accéder à l’os. Des axes d’améliorations ont été proposés pour la gingivectomie (laser, bistouri électrique) mais l’ostéotomie reste invasive dans la technique conventionnelle. Une technique plus récente implique une ostéotomie sans élévation de lambeau chirurgical, dite à « ciel fermé » ou « flapless » en anglais. Cela a permis de se poser la question de l’efficacité de cette technique en comparaison avec la technique conventionnelle. Ce travail explore l’évolution des techniques d’élongation coronaire, en particulier une approche sans lambeau « flapless » réalisée avec des instruments soniques. Une comparaison entre les méthodes classique et « flapless » est également discutée, offrant une perspective sur l’avenir de cette intervention moins invasive
Challenges in chirality induction in iron oxide nanoparticles: in situ vs ex situ growth on helical nanoplatforms
No full textInternational audienceThe integration of chiral and magnetic properties has gained increasing interest due to its potential for enabling magneto-chiral phenomena. However, the development of nanoscale chiral systems that exhibit strong responsiveness to both light and magnetic fields remains largely underexplored. In this context, we investigate the use of silica nanohelices as a chiral platform for inducing circular dichroism (CD) in iron oxide nanoparticles (NPs). Two strategies are compared: an ex situ approach, where the NPs are synthesized independently and then grafted onto the helices, and an in situ approach, where the NPs are directly formed on the surface of the helices. This comparison enables us to evaluate the chirality induction arising from helicoidal assembly versus chiral shape, respectively. The efficiency of each strategy was assessed by electronic CD (ECD) and magnetic CD (MCD) spectroscopies. The results show that chirality induction on iron oxide nanocrystals is negligible with the ex situ method, whereas weak but unambiguous ECD signals are observed following the in situ approach. Furthermore, a comparative analysis of chirality induction in magnetite (Fe3O4) vs. maghemite (γ-Fe2O3) with both strategies is presented and discussed
Scheduling Strategies for Partially-Replicable Task Chains on Two Types of Resources
No full textInternational audienceThe arrival of heterogeneous (or hybrid) multicore architectures on parallel platforms has brought new performance opportunities for applications and efficiency opportunities to systems. They have also increased the challenges related to thread scheduling, as tasks' execution times will vary depending if they are placed in big (performance) cores or little (efficient) ones. In this paper, we focus on the challenges heterogeneous multicore problems bring to partially-replicable task chains, such as the ones that implement digital communication standards in Software-Defined Radio (SDR). Our objective is to maximize the throughput of these task chains while also minimizing their power consumption. We model this problem as a pipelined workflow scheduling problem using pipelined and replicated parallelism on two types of resources whose objectives are to minimize the period and to use as many little cores as necessary. We propose two greedy heuristics (FERTAC and 2CATAC) and one optimal dynamic programming (HeRAD) solution to the problem. We evaluate our solutions and compare the quality of their schedules (in period and resource utilization) and their execution times using synthetic task chains and an implementation of the DVB-S2 communication standard running on StreamPU. Our results demonstrate the benefits and drawbacks of the different proposed solutions. On average, FERTAC and 2CATAC achieve near-optimal solutions, with periods that are less than 10% worse than the optimal (HeRAD) using fewer than 2 extra cores. These three scheduling strategies now enable programmers and users of StreamPU to transparently make use of heterogeneous multicore processors and achieve throughputs that differ from their theoretical maximums by less than 8% on average
La construction du droit processuel de l'éxécution par la fondamentalisation des droits. Conférence-débat
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EcoSearch: A Constant-Delay Best-First Search Algorithm for Program Synthesis
No full textInternational audienceMany approaches to program synthesis perform a combinatorial search within a large space of programs to find one that satisfies a given specification. To tame the search space blowup, previous works introduced probabilistic and neural approaches to guide this combinatorial search by inducing heuristic cost functions. Best-first search algorithms ensure to search in the exact order induced by the cost function, significantly reducing the portion of the program space to be explored. We present a new best-first search algorithm called EcoSearch, which is the first constant-delay algorithm for pre-generation cost function: the amount of compute required between outputting two programs is constant, and in particular does not increase over time. This key property yields important speedups: we observe that EcoSearch outperforms its predecessors on two classic domains