An extension of a Liapunov approach to the stabilization of second order coupled systems

This paper deals with the convergence to 0 of the energy of the solutions of a second order linear coupled system. In order to obtain the energy decay, we exhibit a Liapunov function

A reliability-based approach for influence maximization using the evidence theory

The influence maximization is the problem of finding a set of social network users, called influencers, that can trigger a large cascade of propagation. Influencers are very beneficial to make a marketing campaign goes viral through social networks for example. In this paper, we propose an influence measure that combines many influence indicators. Besides, we consider the reliability of each influence indicator and we present a distance-based process that allows to estimate the reliability of each indicator. The proposed measure is defined under the framework of the theory of belief functions. Furthermore, the reliability-based influence measure is used with an influence maximization model to select a set of users that are able to maximize the influence in the network. Finally, we present a set of experiments on a dataset collected from Twitter. These experiments show the performance of the proposed solution in detecting social influencers with good quality.Comment: 14 pages, 8 figures, DaWak 2017 conferenc

Prise en charge de l’atresie choanale

Introduction: L’atrésie choanale est une malformation congénitale rare mais non exceptionnelle. Le but de notre travail est d’étudier les caractéristiques épidémiologiques, cliniques et radiologiques de cette pathologie, et de discuter les différentes modalités thérapeutiques et leurs résultats respectifs.Matériel et méthodes: Notre étude rétrospective porte sur une série de 12 cas d’atrésie choanale opérés dans notre service entre 2002 et 2010. Tous les patients ont bénéficié d’un examen ORL et d’une tomodensitométrie du massif facial. Tous les patients ont été opérés sous anesthésie générale.Résultats: L’âge moyen était de 10,7 ans (3 jours - 31 ans) et le sex-ratio était de 2. L’atteinte était unilatérale dans 66,6% et bilatérale dans 33,3% des cas. Dans 16% des cas, l’atrésie rentrait dans le cadre d’un syndrome polymalformatif. La technique opératoire utilisée était la voie  endoscopique dans 10 cas et la voie transpalatine dans 2 cas. Le taux de succès global était de 75%. Trois cas de récidive ont été notés. Ils ont été réopérés par voie endonasale.Conclusion: L’endoscopie nasale et la TDM permettent le diagnostic positif de l’atrésie choanale. Le traitement de référence actuellement est la chirurgie par voie endonasale.Mots-clés: atrésie choanale, malformation, obstruction nasale, endoscopie, tomodensitométrie, chirurgie endonasal

Simulation de l'effet des surcharges sur le comportement mécanique des P.T.H à couples de matériaux différents

International audienceThe reliability of total hip arthroplasties (THA) is not any more to show. It is allowed by all. Indeed, the retreat of such interventions exceeds now fifteen years and the hopes which the first clinicians formulated are now realities. Nevertheless, the deformation and the wear of cup components remain an inevitable mechanism and loosening appear in long-term. Prevention of loosening passes by the reduction of this wear. This study deals with a simulation of the effect of overloads on THA with different materials. Three materials are analyzed in order to choose the couple which has better bio functionality.La fiabilité des arthroplasties totales de hanche n'est plus à démontrer. Elle est admise par tous. En effet, le recul de telles interventions dépasse maintenant quinze ans et les espérances que les premiers cliniciens ont formulées à leur égard sont maintenant des réalités. Néanmoins, la déformation et l'usure des composants acétabulaires restent un mécanisme inévitable et des descellements asceptiques apparaissent à long terme. La prévention du descellement passe donc par la réduction de cette usure. Cette étude porte sur une simulation de l'effet de certains paramètres mécaniques, entre autres « les surcharges » sur le comportement des PTH hybrides à couples de matériaux différents. Trois couples de matériaux sont analysés, en vue de choisir celui qui offre une meilleure biofonctionnalité

Recovery, assessment, and molecular characterization of minor olive genotypes in Tunisia

Olive is one of the oldest cultivated species in the Mediterranean Basin, including Tunisia, where it has a wide diversity, with more than 200 cultivars, of both wild and feral forms. Many minor cultivars are still present in marginal areas of Tunisia, where they are maintained by farmers in small local groves, but they are poorly characterized and evaluated. In order to recover this neglected germplasm, surveys were conducted in different areas, and 31 genotypes were collected, molecularly characterized with 12 nuclear microsatellite (simple sequence repeat (SSR)) markers, and compared with 26 reference cultivars present in the Tunisian National Olive collection. The analysis revealed an overall high genetic diversity of this olive’s germplasm, but also discovered the presence of synonymies and homonymies among the commercialized varieties. The structure analysis showed the presence of different gene pools in the analyzed germplasm. In particular, the marginal germplasm from Ras Jbal and Azmour is characterized by gene pools not present in commercial (Nurseries) varieties, pointing out the very narrow genetic base of the commercialized olive material in Tunisia, and the need to broaden it to avoid the risk of genetic erosion of this species in this country

Sleep as a model to understand neuroplasticity and recovery after stroke : observational, perturbational and interventional approaches

Our own experiences with disturbances to sleep demonstrate its crucial role in the recovery of cognitive functions. This importance is likely enhanced in the recovery from stroke; both in terms of its physiology and cognitive abilities. Decades of experimental research have highlighted which aspects and mechanisms of sleep are likely to underlie these forms of recovery. Conversely, damage to certain areas of the brain, as well as the indirect effects of stroke, may disrupt sleep. However, only limited research has been conducted which seeks to directly explore this bidirectional link between both the macro and micro-architecture of sleep and stroke. Here we describe a series of semi-independent approaches that aim to establish this link through observational, perturbational, and interventional experiments. Our primary aim is to describe the methodology for future clinical and translational research needed to delineate competing accounts of the current data. At the observational level we suggest the use of high-density EEG recording, combined analysis of macro and micro-architecture of sleep, detailed analysis of the stroke lesion, and sensitive measures of functional recovery. The perturbational approach attempts to find the causal links between sleep and stroke. We promote the use of transcranial magnetic stimulation combined with EEG to examine the cortical dynamics of the peri-infarct stroke area. Translational research should take this a step further using optogenetic techniques targeting more specific cell populations. The interventional approach focuses on how the same clinical and translational perturbational techniques can be adapted to influence long-term recovery of function

Principles of environmentally-sustainable anaesthesia: a global consensus statement from the World Federation of Societies of Anaesthesiologists

The Earth’s mean surface temperature is already approximately 1.1°C higher than pre-industrial levels. Exceeding a mean 1.5°C rise by 2050 will make global adaptation to the consequences of climate change less possible. To protect public health, anaesthesia providers need to reduce the contribution their practice makes to global warming. We convened a Working Group of 45 anaesthesia providers with a recognised interest in sustainability, and used a three-stage modified Delphi consensus process to agree on principles of environmentally sustainable anaesthesia that are achievable worldwide. The Working Group agreed on the following three important underlying statements: patient safety should not be compromised by sustainable anaesthetic practices; high-, middle- and low-income countries should support each other appropriately in delivering sustainable healthcare (including anaesthesia); and healthcare systems should be mandated to reduce their contribution to global warming. We set out seven fundamental principles to guide anaesthesia providers in the move to environmentally sustainable practice, including: choice of medications and equipment; minimising waste and overuse of resources; and addressing environmental sustainability in anaesthetists’ education, research, quality improvement and local healthcare leadership activities. These changes are achievable with minimal material resource and financial investment, and should undergo re-evaluation and updates as better evidence is published. This paper discusses each principle individually, and directs readers towards further important references

Exploiting Mitochondrial Dysfunction for Effective Elimination of Imatinib-Resistant Leukemic Cells

Challenges today concern chronic myeloid leukemia (CML) patients resistant to imatinib. There is growing evidence that imatinib-resistant leukemic cells present abnormal glucose metabolism but the impact on mitochondria has been neglected. Our work aimed to better understand and exploit the metabolic alterations of imatinib-resistant leukemic cells. Imatinib-resistant cells presented high glycolysis as compared to sensitive cells. Consistently, expression of key glycolytic enzymes, at least partly mediated by HIF-1α, was modified in imatinib-resistant cells suggesting that imatinib-resistant cells uncouple glycolytic flux from pyruvate oxidation. Interestingly, mitochondria of imatinib-resistant cells exhibited accumulation of TCA cycle intermediates, increased NADH and low oxygen consumption. These mitochondrial alterations due to the partial failure of ETC were further confirmed in leukemic cells isolated from some imatinib-resistant CML patients. As a consequence, mitochondria generated more ROS than those of imatinib-sensitive cells. This, in turn, resulted in increased death of imatinib-resistant leukemic cells following in vitro or in vivo treatment with the pro-oxidants, PEITC and Trisenox, in a syngeneic mouse tumor model. Conversely, inhibition of glycolysis caused derepression of respiration leading to lower cellular ROS. In conclusion, these findings indicate that imatinib-resistant leukemic cells have an unexpected mitochondrial dysfunction that could be exploited for selective therapeutic intervention