703 research outputs found

    Diagnostic mycologique d’une mucormycose dissĂ©minĂ©e chez un enfant atteint d’aplasie mĂ©dullaire idiopathique : Ă  propos d’un cas: Mucological diagnosis of disseminated mucormycosis in a patient with idiopathic aplastic anemia: case report

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    Mucormycosis is a rare, opportunistic and aggressive fungal infectious disease occurring mainly in immunocompromised individuals. It is invasive with most often, a fatal evolution. It is due to a filamentous fungi of the order mucorales. The transmission is by air, with a nasal-sinus tropism. However, other localizations including digestive, cutaneous pulmonary and disseminated localizations are possible but rare. The clinical signs are not specific, which delays the diagnosis. The Clinical expression of mucormycosis includes nasal, neurological, cutaneous and ophthalmologic signs in a context of fever and deterioration of the overall condition of the patient. The positive diagnosis is based on mycological and pathological examination. The prognosis is dark, depending on the early diagnosis and treatment. Herein, we report a case of an 11-year-old child with disseminated mucormycosis whose evolution was pejorative. La murcomycose est une pathologie infectieuse fongique rare, survenant surtout chez les sujets immunodĂ©primĂ©s, d’évolution fatale le plus souvent. La transmission se fait par voie aĂ©rienne, avec un tropisme naso-sinusien par ailleurs d’autres localisations : pulmonaire cutanĂ©e digestive et dissĂ©minĂ©es sont possibles mais exceptionnelles. Les signes cliniques sont peu spĂ©cifiques ce qui retarde le diagnostic qui repose sur l’examen mycologique et anatomopathologique des tissus infectĂ©s. Nous rapportons le cas d’une mucormycose dissĂ©minĂ©e Ă  point de dĂ©part cutanĂ© chez un enfant suivi pour aplasie mĂ©dullaire idiopathique, dont l’évolution Ă©tait pĂ©jorative

    A two dimensional fluid model for TCP/AQM analysis

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    This work proposes a new mathematical model for the TCP/AQM system that aims to improve the accuracy of existing fluid models, especially with respect to the sequential events that occur in the network. The analysis is based on the consideration of two time bases, one at the queue's router level and the other at the congestion window level, which leads to the derivation of a new nonlinear two-dimensional fluid model for Internet congestion control. To avoid the difficult task of assessing stability of a 2D nonlinear dynamic model, we perform a local stability analysis of a 2D linear TCP AQM model. By constructing a new two dimensional second order Bessel Legendre Lyapunov functional, new matrix inequalities are derived to evaluate the stability of the 0-input system and to synthesize a feedback controller. Finally, two Internet traffic scenarios, with state space matrices for replicability, are presented, demonstrating the validity of the theoretical results.Comment: Active queue management, network assisted congestion control, TCP/AQM, 2D time delay systems, Roesser model, 2D second order bessel Legendre, Lyapuno

    Inhibitory synapse dysfunction and epileptic susceptibility associated with KIF2A deletion in cortical interneurons

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    Malformation of cortical development (MCD) is a family of neurodevelopmental disorders, which usually manifest with intellectual disability and early-life epileptic seizures. Mutations in genes encoding microtubules (MT) and MT-associated proteins are one of the most frequent causes of MCD in humans. KIF2A is an atypical kinesin that depolymerizes MT in ATP-dependent manner and regulates MT dynamics. In humans, single de novo mutations in KIF2A are associated with MCD with epileptic seizures, posterior pachygyria, microcephaly, and partial agenesis of corpus callosum. In this study, we conditionally ablated KIF2A in forebrain inhibitory neurons and assessed its role in development and function of inhibitory cortical circuits. We report that adult mice with specific deletion of KIF2A in GABAergic interneurons display abnormal behavior and increased susceptibility to epilepsy. KIF2A is essential for tangential migration of cortical interneurons, their positioning in the cerebral cortex, and for formation of inhibitory synapses in vivo. Our results shed light on how KIF2A deregulation triggers functional alterations in neuronal circuitries and contributes to epilepsy

    control based on saturated time-delay systems theory of mach number in wind tunnels

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    ProducciĂłn CientĂ­ficaA proposal for the regulation of the Mach number in wind tunnels using static state feedback for saturated systems with delays is presented here. As these systems can be precisely represented by a time-delay model with saturating inputs, a general solution for discrete delayed systems with saturating input is first derived. This general solution is based on modeling the saturation using a Lyapunov functional, using free weighting matrices and maximizing the set of admissible initial conditions. The application of this solution to the control of the Mach number in a wind tunnel is then presented, illustrating the design procedures.MiCInn Project DPI2014-54530-

    Difficulté de la prise en charge de la Leucémie aiguë au cours de la grossesse au Maroc

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    L’association de la leucĂ©mie aiguĂ« (LA) et grossesse est rare. Son incidence est estimĂ©e Ă  1/100 000 grossesses. Dans les 2/3 des cas ce sont des leucĂ©mies aiguĂ«s myĂ©loblastiques. Le diagnostic est gĂ©nĂ©ralement fait pendant le 2Ăšme et le 3Ăšme trimestre. Elle pose un problĂšme Ă©thique et thĂ©rapeutique car La chimiothĂ©rapie au cours de la grossesse expose le foetus aux complications. Tout retard ou changement de traitement pour sauvetage foetal risque d’aggraver le pronostic maternel. L’objectif de ce travail est de dĂ©crire les particularitĂ©s de la prise en charge de la leucĂ©mie aiguĂ« chez la femme enceinte. Etude prospective descriptive des femmes enceintes atteintes de leucĂ©mie aiguĂ« colligĂ©es au service d’hĂ©matologie et d’oncologie pĂ©diatrique Ă  l’hĂŽpital 20 AoĂ»t du CHU IBN ROCHD de Casablanca depuis janvier 2009 Ă  AoĂ»t 2011. Le diagnostic de LA est fait selon les critĂšres de l’OMS. Le traitement Ă©tait instaurĂ© aprĂšs consentement des patientes selon le type de LA. Huit cas de leucĂ©mies aiguĂ«s au cours de la grossesse sont colligĂ©s au service d’hĂ©matologie et d’oncologie pĂ©diatrique Ă  l’hĂŽpital 20 AoĂ»t du CHU IBN ROCHD de Casablanca. Sept leucĂ©mies aiguĂ«s myĂ©loblastiques et une leucĂ©mie aiguĂ« lymphoblastique. Quatre cas ont Ă©tĂ© diagnostiquĂ©s durant le 1er trimestre de la grossesse, Un cas pendant le 2Ăšme trimestre et 3 cas pendant le 3Ăšme trimestre. L’accouchement est par cĂ©sarienne programmĂ©e dans 2 cas et par voie basse dans 3 cas dont un est prĂ©maturĂ©, 2 fausses couches et une mort foetal aprĂšs dĂ©cĂšs maternel. Trois patientes ont reçue la chimiothĂ©rapie durant la grossesse aprĂšs consentement Ă©clairĂ© et les 5 autres aprĂšs l’accouchement. Les 5 nouveau-nĂ©s sont bien portants avec un bilan malformatif nĂ©gatif. L’association de la leucĂ©mie aiguĂ« et grossesse est un Ă©vĂšnement rare. Elle nĂ©cessite une prise en charge multidisciplinaire tenant compte des impĂ©ratifs de la maladie et de son traitement, de la femme et de son dĂ©sire de grossesse ainsi que des dimensions Ă©thiques et morales.Pan African Medical Journal 2012; 13:

    congestion control of data network by using anti-windup approach

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    ProducciĂłn CientĂ­ficaAn Active Queue Management (AQM) scheme is design to control congestion in data networks, which includes anti-windup to deal with control signal saturation. More precisely, a methodology is proposed to design advanced AQM systems capable of regulating queue size even in the presence of significant disturbances. Hence, we first provide sufficient conditions for stabilization for the equivalent class of systems, which are derived in terms of LMI: this makes possible to derive optimization solutions that ensure performance and stability for a large domain of initial conditions. This approach is validated with a numerical example that illustrates the methodology, and the improvements with respect to previous congestion control solutions

    Finite-Time Stability for Discrete-Time Systems with Time-Varying Delays and Nonlinear Perturbations Using Relaxed Summation Inequality

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    Producción CientíficaThis article deals with the problem of delay-dependent finite-time stability (FTS) for delayed discrete-time systems with nonlinear perturbations. First, based on a Lyapunov–Krasovskii Functional, delay-dependent FTS conditions are provided by introducing some free-weighting matrices. Then, a new reduced free-matrix-based inequality is established to estimate the single summation term. The dimensions of these free matrices integral in our results are less than those obtained in the literature. This reduction in the number of variables does not mean that our method is a particular case but simply that our approach is completely different from the others and therefore our method is more effective. Thus, less conservative design conditions are obtained in this paper in terms of linear matrix inequalities (LMIs) and solved using MATLAB’s LMI toolbox to achieve the desired performance. The purpose of this paper is to derive sufficient conditions that ensure the finite-time stability of the discrete-time system. Finally, numerical examples are examined to show the advantage and effectiveness of the proposed results.MICInn, PID2021-123654OB-C31MICInn, PID2020-112871RB-C2

    congestion control in tcp/ip routers based on sampled-data systems theory

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    Producción CientíficaA methodology for designing congestion controllers, based on active queue management (AQM), is presented here. The congestion control law is derived using sampled-data H∞ systems theory. More precisely, a sampled-data state feedback that guarantees the stability of the closed-loop system and satisfies a H∞ disturbance attenuation level is derived here, based on sufficient conditions expressed in terms of linear matrix inequalities. The effectiveness of the developed technique is validated on two examples

    Seven-Pass Transmembrane Cadherins: Roles and Emerging Mechanisms in Axonal and Dendritic Patterning

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    The Flamingo/Celsr seven-transmembrane cadherins represent a conserved subgroup of the cadherin superfamily involved in multiple aspects of development. In the developing nervous system, Fmi/Celsr control axonal blueprint and dendritic morphogenesis from invertebrates to mammals. As expected from their molecular structure, seven-transmembrane cadherins can induce cell–cell homophilic interactions but also intracellular signaling. Fmi/Celsr is known to regulate planar cell polarity (PCP) through interactions with PCP proteins. In the nervous system, Fmi/Celsr can function in collaboration with or independently of other PCP genes. Here, we focus on recent studies which show that seven-transmembrane cadherins use distinct molecular mechanisms to achieve diverse functions in the development of the nervous system
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