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Number of Fixed Points and Disjoint Cycles in Monotone Boolean Networks
No full textInternational audienceGiven a digraph G, a lot of attention has been deserven on the maximum number φ(G) of fixed points in a Boolean network f : {0, 1} n → {0, 1} n with G as interaction graph. In particular, a central problem in network coding consists in studying the optimality of the feedback bound φ(G) ≤ 2 τ , where τ is the minimum size of a feedback vertex set of G. In this paper, we study the maximum number φ m (G) of fixed points in a monotone Boolean network with interaction graph G. We establish new upper and lower bounds on φ m (G) that depends on the cycle structure of G. In addition to τ , the involved parameters are the maximum number ν of vertex-disjoint cycles, and the maximum number ν * of vertex-disjoint cycles verifying some additional technical conditions. We improve the feedback bound 2 τ by proving that φ m (G) is at most the largest sub-lattice of {0, 1} τ without chain of size ν + 2, and without another forbidden pattern described by two disjoint antichains of size ν * + 1. Then, we prove two optimal lower bounds: φ m (G) ≥ ν + 1 and φ m (G) ≥ 2 ν *. As a consequence, we get the following characterization: φ m (G) = 2 τ if and only if ν * = τ. As another consequence, we get that if c is the maximum length of a chordless cycle of G then 2 ν/3 c ≤ φ m (G) ≤ 2 cν. Finally, with the techniques introduced, we establish an upper bound on the number of fixed points of any Boolean network according to its signed interaction graph
L’interposition de personnes dans la reprise d’une entreprise en difficulté
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Position estimation from direction or range measurements
No full textInternational audienceThis paper revisits the problems of estimating the position of an object moving in n (≥ 2)-dimensional Euclidean space using velocity measurements and either direction or range measurements of one or multiple source points. The proposed solutions exploit the Continuous Riccati Equation (CRE) to calculate observer gains yielding global uniform exponential stability of zero estimation errors, also when the measured velocity is biased by an unknown constant vector or when direction measurements are corrupted by an unknown constant bias. With respect to prior contributions on these subjects they provide a coherent generalization of existing solutions with the preoccupation of pointing out general and explicit persistent excitation (p.e.) conditions whose satisfaction ensures uniform exponential stability of the observers
Riccati Observers for the Non-Stationary PnP Problem
No full textInternational audienceThis paper revisits the problem of estimating the pose (position and orientation) of a body in 3D space with respect to (w.r.t.) an inertial frame by using i) the knowledge of source points positions in the inertial frame, ii) the measurements of the body angular velocity expressed in the body's frame iii) the measurements of the body translational velocity, either in the body frame or in the inertial frame, and iv) source points bearing measurements performed in the body frame. An important difference with the much studied static Perspective-n-Point (PnP) problem addressed with iterative algorithms is that body motion is not only allowed but also used as a source of information that improves the estimation possibilities. With respect to the probabilistic framework commonly used in other studies that develop Extended Kalman filter (EKF) solutions, the deterministic approach here adopted is better suited to point out the observability conditions, that involve the number and disposition of the source points in combination with body motion characteristics, under which the proposed observers ensure robust estimation of the body pose. These observers are here named Riccati observers because of the instrumental role played by the Continuous Riccati equation (CRE) in the design of the observers and in the Lyapunov stability and convergence analysis that we develop independently of the well-known complementary (either deterministic or probabilistic) optimality properties associated with Kalman filtering. The set of these observers also encompasses Extended Kalman filter solutions. Another contribution of the present study is to show the importance of using body motion to improve the observers performance and, when this is possible, of measuring the body translational velocity in the inertial frame rather than in the body frame to allow for the body pose estimation from a single source point taken as the origin of the inertial frame. This latter possibility finds a natural extension in the Simultaneous Localization and Mapping (SLAM) problem in Robotics
L'apport du e-learning dans la formation initiale et continue en odontologie
No full textDepuis le décret du 2 juin 2006 la formation continue est devenue obligatoire pour tous les chirurgiens dentistes. Le e-learning ou apprentissage en ligne offre la possibilité, grâce aux TICE, de bénéficier d’une formation à distance, adaptée à ses besoins et accessible à tout moment. L’objectif de cette thèse est de faire le point en 2017 sur les différentes méthodes de e-learning, de lister ses avantages et ses inconvénients et de mettre en exergue ses bénéfices en terme d’acquisition de connaissances et de compétences. Il apparait en effet que le terme générique de e-learning inclus un grand nombre de technologie numériques et de méthodes pédagogiques différentes. La qualité de la formation dispensée sera donc dépendante de l’ensemble de l’équipe impliquée dans la conception des programmes qui devront s’adapter aux différents profils d’apprentissage des apprenants. Les formateurs impliqués dans les formations en ligne devront dans la conception et dans l’encadrement des participants adapter les modèles pédagogiques utilisés lors de formations présentielles. Il existe différentes catégories d’outils utilisables mais c’est la stratégie pédagogique qui permettra de choisir les plus adaptés à l’objectif recherché. Nous décrirons les différentes offres de formation en e-learning que l’on retrouve actuellement pour la formation des chirurgiens- dentistes et la pertinence de celles ci dans notre profession. Par ses caractéristiques propres et ses qualités, l’apprentissage en ligne est un élément essentiel et incontournable de la formation des chirurgiens dentistes
Pain and quality of life evaluation in patients with localized epidermolysis bullosa simplex
No full textInternational audienceBackgroundA localized form of epidermolysis bullosa simplex (EBS-l) is considered one of the mildest forms of epidermolysis bullosa (EB), with blisters limited to the palms and soles. However, these lesions can be very painful. The aim of the study was to characterize pain in patients with EBS-l and evaluate its impact on quality of life (QoL). Patients were contacted via the Research Group of the French Society of Pediatric Dermatology and the association of EB patients (DEBRA France). One investigator used a standardized questionnaire that included validated scales for pain and QoL for a telephone interview.ResultsWe included 57 patients (27 children). All patients had pain: the mean pain on a 10-mm visual analog scale was >5 for most adults (90%) and children ≥8 years old (94%) when blisters were present and for most adults (73%) and about half of the children ≥ age 8 (53%) during dressing changes. Similar results were found for younger patients. Overall, 75% of patients had neuropathic pain; for 55% of children and 73% of adults, the pain had a moderate to severe impact on QOL. Only seven patients used premedication before changing dressings and seven regularly used oral treatment for chronic pain. A total of 21% and 23% of patients used non-steroidal anti-inflammatory drugs and grade 2 analgesics, respectively. These treatments were not effective for neuropathic pain. Six patients tried 5% lidocaine plasters on their feet, with good efficacy.ConclusionsEBS-l patients have frequent and severe pain with neuropathic characteristics. This pain is undertreated and affects QoL
Formation Doctorale "Éthique de la recherche et intégrité scientifique" : Une formation proposée par l'école des docteurs de Toulouse
No full textDoctoralLes écoles doctorales du site toulousain ont demandé fin 2015 que l’École Des Docteurs pilote un groupe de travail permettant de développer une formation à « l’Éthique de la Recherche et à l’intégrité scientifique ». Un groupe de chercheurs et d’enseignants-chercheurs, identifiés grâce à un appel à participation diffusé dans les écoles doctorales toulousaines, a développé un « kit de formation » comprenant : un diaporama support de cours, des propositions de dilemmes éthiques formatés et ce guide pratique à destination des formateurs. Ces documents sont inspirés du Cahier « Proposition de formation doctorale ; Initiation à l’éthique de la recherche scientifique » de la CERNA (Commission de réflexion sur l’Éthique de la Recherche en sciences et technologies du Numérique d’Allistene), des propositions des différents acteurs du groupe de travail, issus de disciplines diverses et du retour d’expérience des 17 premières journées de formation données à des groupes de doctorants issus de différentes écoles doctorales . L’Université de Toulouse est la première en France où cette formation est dispensée de manière transversale à tous les doctorants. Les échanges interdisciplinaires (entre formateurs et entre étudiants) sont particulièrement fructueux pour la dynamique de formation, qui se doit d’être participative.Cette formation est donnée en binôme, chaque binôme comprenant un intervenant issu des disciplines science, technologie, santé, ingénierie et un intervenant issu des sciences humaines et sociale, droit économie, gestion. Pendant l’année universitaire 2015-2016, cette formation a été testée lors de 4 sessions. Elle a été reconduite à plus grande échelle pour l’année universitaire 2016-2017, avec des binômes « ancien formateur/nouveau formateur », permettant ainsi d’assurer la formation des formateurs tout en conservant la cruciale complémentarité disciplinaire. À ce jour sur le site toulousain, ce sont donc une vingtaine d’intervenants chercheurs, enseignants-chercheurs, ingénieurs et personnels techniques de recherche et de formation qui ont formé plus de 300 doctorants de disciplines et horizons différents
Identification of DmTTLL5 as a Major Tubulin Glutamylase in the Drosophila Nervous System
No full textInternational audienceMicrotubules (MTs) play crucial roles during neuronal life. They are formed by heterodimers of alpha and beta-tubulins, which are subjected to several post-translational modifications (PTMs). Amongst them, glutamylation consists in the reversible addition of a variable number of glutamate residues to the C-terminal tails of tubulins. Glutamylation is the most abundant MT PTM in the mammalian adult brain, suggesting that it plays an important role in the nervous system (NS). Here, we show that the previously uncharacterized CG31108 gene encodes an alpha-tubulin glutamylase acting in the Drosophila NS. We show that this glutamylase, which we named DmTTLL5, initiates MT glutamylation specifically on alpha-tubulin, which are the only glutamylated tubulin in the Drosophila brain. In DmTTLL5 mutants, MT glutamylation was not detected in the NS, allowing for determining its potential function. DmTTLL5 mutants are viable and we did not find any defect in vesicular axonal transport, synapse morphology and larval locomotion. Moreover, DmTTLL5 mutant flies display normal negative geotaxis behavior and their lifespan is not altered. Thus, our work identifies DmTTLL5 as the major enzyme responsible for initiating neuronal MT glutamylation specifically on alpha-tubulin and we show that the absence of MT glutamylation is not detrimental for Drosophila NS function