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Evry, France

The Université d'Évry Val-d'Essonne is a French public university located in Évry , Île-de-France, France and is one of the six founding members of UniverSud Paris. This University founded in 1991 , is located in a “ville nouvelle” which is dynamic and constantly evolving Wikipedia.

Regnault D.,University of Evry Val dEssonne
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

Cellular automata are a model of parallel computing. It is well known that simple deterministic cellular automata may exhibit complex behaviors such as Turing universality [3,13] but only few results are known about complex behaviors of probabilistic cellular automata. Several studies have focused on a specific probabilistic dynamics: α-asynchronism where at each time step each cell has a probability α to be updated. Experimental studies [5] followed by mathematical analysis [2,4,7,8] have permitted to exhibit simple rules with interesting behaviors. Among these behaviors, most of these studies conjectured that some cellular automata exhibit a polynomial/exponential phase transition on their convergence time, i.e. the time to reach a stable configuration. The study of these phase transitions is crucial to understand the behaviors which appear at low synchronicity. A first analysis [14] proved the existence of the exponential phase in cellular automaton FLIP-IF-NOT-ALL-EQUAL but failed to prove the existence of the polynomial phase. In this paper, we prove the existence of a polynomial/exponential phase transition in a cellular automaton called FLIP-IF-NOT-ALL-0. © 2013 Springer-Verlag. Source

Gaigeot M.-P.,University of Evry Val dEssonne | Gaigeot M.-P.,Institut Universitaire de France
Physical Chemistry Chemical Physics

Theoretical spectroscopy is mandatory for a precise understanding and assignment of experimental spectra recorded at finite temperature. We review here room temperature DFT-based molecular dynamics simulations for the purpose of interpreting finite temperature infrared spectra of peptides of increasing size and complexity, in terms of temperature-dependent conformational dynamics and flexibility, and vibrational anharmonicities (potential energy surface anharmonicities, vibrational mode couplings and dipole anharmonicities). We take examples from our research projects in order to illustrate the main key-points and strengths of dynamical spectra modeling in that context. The calculations are presented in relation to room temperature gas phase IR-MPD experiments and room temperature liquid phase IR absorption experiments. These illustrations of floppy polypeptides have been chosen in order to convey the following ideas: temperature-dependent spectra modeling is pivotal for a precise understanding of gas phase spectra recorded at room temperature, including conformational dynamics and vibrational anharmonicities; harmonic spectroscopy (as commonly performed in the literature) can be misleading and even erroneous for a proper interpretation of spectra recorded at finite temperature; taking into account vibrational anharmonicities is pivotal for a proper interplay between theory and experiments; amide I-III bands are not necessarily the most relevant fingerprints for unraveling the local structures of peptides and more complex systems; liquid phase simulations have unraveled relationships between the zwitterionic properties of the peptide bonds and infrared signatures. The review presents a state-of-the-art account of the domain and offers perspectives and new developments for future still more challenging applications. © the Owner Societies. Source

Bayad A.,University of Evry Val dEssonne | Kim T.,Kwangwoon University
Russian Journal of Mathematical Physics

In this paper, we give relations involving values of q-Bernoulli, q-Euler, and Bernstein polynomials. Using these relations, we obtain some interesting identities on the q-Bernoulli, q-Euler, and Bernstein polynomials. © 2011 Pleiades Publishing, Ltd. Source

Bouveyron C.,Paris-Sorbonne University | Brunet C.,University of Evry Val dEssonne
Statistics and Computing

Clustering in high-dimensional spaces is nowadays a recurrent problem in many scientific domains but remains a difficult task from both the clustering accuracy and the result understanding points of view. This paper presents a discriminative latent mixture (DLM) model which fits the data in a latent orthonormal discriminative subspace with an intrinsic dimension lower than the dimension of the original space. By constraining model parameters within and between groups, a family of 12 parsimonious DLM models is exhibited which allows to fit onto various situations. An estimation algorithm, called the Fisher-EM algorithm, is also proposed for estimating both the mixture parameters and the discriminative subspace. Experiments on simulated and real datasets highlight the good performance of the proposed approach as compared to existing clustering methods while providing a useful representation of the clustered data. The method is as well applied to the clustering of mass spectrometry data. © 2011 Springer Science+Business Media, LLC. Source

D'Angelo P.,University of Rome La Sapienza | Spezia R.,University of Evry Val dEssonne
Chemistry - A European Journal

The latest experimental and theoretical studies on structural and dynamical properties of lanthanoid(III) and actinoid(III) ions in water have been reviewed. In the last years, most of the issues about lanthanoid(III) hydration have been resolved combining X-ray absorption experiments and different theoretical methods. Since 2008 an effort has been made to treat the entire series thus obtaining coherent sets of experimental and theoretical results that were lately put together in such a way that it was possible to derive new basic properties, such as effective ionic radii, across the series. While for the hydration of lanthanoids(III) many experiments and simulations have been reported, the hydration of actinoids(III) was less investigated. There are some experiments performed by different research groups and few simulations that we discuss in this review. Currently, there are enough results that it is possible to gain some understanding of the hydration behavior of lanthanoids(III) and actinoids(III). The ultimate goal of this review is to provide clues on the analogies and differences between the two series. These aspects are connected to several issues: 1) technological: the separation of these elements that is necessary for recycling and stocking of nuclear waste, 2) practical: because experiments on actinoids need particular care, the definition of possible analogies will give the possibility to use the correct lanthanoid when the information on a specific actinoid is needed, 3) fundamental: related to chemical similarities between the two series. Experiment meets theory: X-ray absorption spectroscopy and theoretical methods succeeded in providing a clear picture of the hydration of lanthanoid(III) and actinoid(III) elements. Structural, dynamic, and thermodynamic properties have been investigated and pave the way for the study of the solvation and complexation of very heavy metals. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

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