El Salabi A.,University of Cardiff |
Walsh T.R.,University of Cardiff |
Walsh T.R.,University of Queensland |
Chouchani C.,University of Carthage
Critical Reviews in Microbiology | Year: 2013
Infectious diseases due to Gram-negative bacteria are a leading cause of morbidity and mortality worldwide. Antimicrobial agents represent one major therapeutic tools implicated to treat these infections. The misuse of antimicrobial agents has resulted in the emergence of resistant strains of Gram-negatives in particular Enterobacteriaceae and non-fermenters; they have an effect not only on a human but on the public health when bacteria use the resistance mechanisms to spread in the hospital environment and to the community outside the hospitals by means of mobile genetic elements. Gram-negative bacteria have become increasingly resistant to antimicrobial agents. They have developed several mechanisms by which they can withstand to antimicrobials, these mechanisms include the production of Extended-spectrum β-lactamases (ESBLs) and carbapenemases, furthermore, Gram-negative bacteria are now capable of spreading such resistance between members of the family Enterobacteriaceae and non-fermenters using mobile genetic elements as vehicles for such resistance mechanisms rendering antibiotics useless. Therefore, addressing the issue of mechanisms of antimicrobial resistance is considered one of most urgent priorities. This review will help to illustrate different resistance mechanisms; ESBLs, carbapenemases encoded by genes carried by mobile genetic elements, which are used by Gram-negative bacteria to escape antimicrobial effect. © 2013 Informa Healthcare USA, Inc.
Kassraoui J.,University of Carthage
Applicable Analysis | Year: 2017
In this paper, we derive high-order terms in the asymptotic expansions of the boundary perturbations of the electromagnetic fields resulting from small perturbations of the shape of an inhomogeneity with (Formula presented.)-boundary in (Formula presented.) for (Formula presented.). For such solutions we provide a rigorous derivation that extends those already derived for small volume conductivity inhomogeneities. Our formulas may be expected to develop effective algorithms, aimed at determining certain properties of the shape of an object based on electromagnetic boundary measurements. © 2017 Informa UK Limited, trading as Taylor & Francis Group
Agency: European Commission | Branch: FP7 | Program: CP-FP-SICA | Phase: SiS-2010-18.104.22.168 | Award Amount: 2.36M | Year: 2011
The overall objective of this proposal is enhancing research cooperation on gender and science between the European Union and the Mediterranean countries. Research cooperation is aimed at better understand the roots of gender inequality in science in the area, taking into account cultural diversities and traditions, and analyse how the Mediterranean countries are addressing this issue. It will deal with gender equality from a twofold perspective: the representation of women in scientific research and technological development and the integration of the gender dimension in research policy. The project will provide state of the art description, data collection and relevant comparative analysis on gender and science in all the Mediterranean countries, focusing on three key themes: statistics on women in science, gender equality policies and research on gender inequalities in science careers. These results will be made accessible to the research community and policy makers via an online database, publishable reports and workshops. With the overall purpose of enhancing networking and steering policy-making on gender and science in the years to come, the project will finally develop recommendations for policy-makers aimed at enhancing the presence of women in scientific research and technological development at all levels and ensuring a better integration of the gender dimension in research policy. The Mediterranean countries included in the proposal are the Mediterranean Partner Countries (MPCs), i.e. the Mediterranean countries included in the list of International Co-operation Partner Countries: Algeria, Egypt, Jordan, Lebanon, Morocco, Palestinian-administered areas, Syrian Arab Republic, Tunisia.
Arouri M.E.H.,EDHEC Business School |
Jouini J.,University of Carthage
Energy Economics | Year: 2012
The objective of this paper is to investigate the volatility spillovers between oil and stock markets in Europe. As not all industries are expected to be equally affected by oil price changes, we conduct our study at both the aggregate as well as sector levels. Empirically, we make use of a recently developed VAR-GARCH approach which allows for transmissions in volatilities. In addition, we analyze the optimal weights and hedge ratios for oil-stock portfolio holdings based on our results. On the whole, our findings show significant volatility spillovers between oil price and sector stock returns, and suggest that a better understanding of those links is crucial for portfolio management in the presence of oil price risk. © 2011 Elsevier B.V.
Karoui A.,University of Carthage
Journal of the Franklin Institute | Year: 2011
In this work, we give a brief description of the theory and the properties of the 1-D and 2-D prolate spheroidal wave functions (PSWFs). Then, we study some efficient methods for the computation of the different PSWFs and their associated eigenvalues. More precisely, we shall develop a quadrature method for the approximation of the 1-D PSWFs. Then, we extend this method to the construction of the 2-D PSWFs that are concentrated on the unit disk. Also, we give a brief review of the quality of approximation of almost band-limited functions by the 1-D PSWFs. Moreover, we use some numerical tests to compare between PSWFs and wavelets as signal processing tools. In particular, we give some numerical tests that highlight the efficiency of the PSWFs in processing band-limited signals. © 2010 The Franklin Institute. Published by Elsevier Ltd. All rights reserved.
Jammazi C.,University of Carthage
IMA Journal of Mathematical Control and Information | Year: 2010
The article gives Lyapunov-type sufficient conditions for partial finite-time and asymptotic stability in which some state variables converge to zero, while the rest converge to constant values that possibly depend on the initial conditions. The article then presents partially asymptotically stabilizing controllers for many non-linear control systems for which continuous asymptotically stabilizing (in the usual sense) controllers are known not to exist.
Naghmouchi I.,University of Carthage
International Journal of Bifurcation and Chaos | Year: 2011
We show that, for monotone graph map f, all the ω-limit sets are finite whenever f has periodic point and for monotone dendrite map, any infinite ω-limit set does not contain periodic points. As a consequence, monotone graph and dendrite maps have no LiYorke pairs. However, we built a homeomorphism on a dendroid with a scrambled set having nonempty interior. © 2011 World Scientific Publishing Company.
Kaaniche M.-B.,University of Carthage |
Bremond F.,French Institute for Research in Computer Science and Automation
IEEE Transactions on Pattern Analysis and Machine Intelligence | Year: 2012
We introduce a new gesture recognition framework based on learning local motion signatures (LMSs) of HOG descriptors introduced by . Our main contribution is to propose a new probabilistic learning-classification scheme based on a reliable tracking of local features. After the generation of these LMSs computed on one individual by tracking Histograms of Oriented Gradient (HOG)  descriptor, we learn a codebook of video-words (i.e., clusters of LMSs) using k-means algorithm on a learning gesture video database. Then, the video-words are compacted to a code-book of codewords by the Maximization of Mutual Information (MMI) algorithm. At the final step, we compare the LMSs generated for a new gesture w.r.t. the learned code-book via the k-nearest neighbors (k-NN) algorithm and a novel voting strategy. Our main contribution is the handling of the N to N mapping between codewords and gesture labels within the proposed voting strategy. Experiments have been carried out on two public gesture databases: KTH  and IXMAS . Results show that the proposed method outperforms recent state-of-the-art methods. © 2012 IEEE.
Jammazi C.,University of Carthage
ESAIM - Control, Optimisation and Calculus of Variations | Year: 2012
We consider chained systems that model various systems of mechanical or biological origin. It is known according to Brockett that this class of systems, which are controllable, is not stabilizable by continuous stationary feedback (i.e. independent of time). Various approaches have been proposed to remedy this problem, especially instationary or discontinuous feedbacks. Here, we look at another stabilization strategy (by continuous stationary or discontinuous feedbacks) to ensure the asymptotic stability even in finite time for some variables, while other variables do converge, and not necessarily toward equilibrium. Furthermore, we build feedbacks that permit to vanish the two first components of the Brockett integrator in finite time, while ensuring the convergence of the last one. The considering feedbacks are continuous and discontinuous and regular outside zero. © EDP Sciences, SMAI, 2011.
Jammazi C.,University of Carthage
Proceedings of the IEEE Conference on Decision and Control | Year: 2013
In this paper, we give a construction of discontinuous feedback laws stabilizing in finite-time all without drift systems. Our construction is based on "sampling control" defined by Clarke et al.  and on Bhat and Bernstein feedback laws for cascaded structures . Moreover, our construction are extended to another family of systems as satellite with two controllers when stabilizability by pure discontinuous feedback laws fails. © 2013 IEEE.