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International audience; The bond behavior of FRP rebars embedded in concrete was studied. A total of forty-eight pull-out specimens were tested. The effects of different parameters of FRP rebars, such as type, shape and diameter, on the bond behavior of FRP rebars and concrete were evaluated. The average bond strength developed by the Aramid, Carbon and Glass FRP bars in pull-out tests was experimentally evaluated. Test results indicated that the average maximum bond strength of FRP rebars varied from 7.6 to 28 MPa depending on surface deformation and diameter. The maximum bond strength of FRP bars to concrete was 28 MPa, which was obtained from sand-coated bars (ISOROD bars). The M-Bar smooth type had the lowest bond behavior in concrete. The surface deformation and type of risen (the mechanical and physical properties of the outer surface) are the characteristics that have the greatest effect on the bond behavior of FRP rebars in concrete. Unlike steel bars, the mode of failure was damage of the outer surface of FRP rebars. Theoretical analyses using the finite element method were conducted to study the effect of FRP rebar type, bonded length and surface characteristics of the FRP bars. The finite element simulation is in good agreement with the experimental results of the pull-out tests obtained from carbon ISOROD bars.

International audience

International audience; We report the design of a millimeter-sized parallel plate free-air ionization chamber 10 (IC) aimed at determining the absolute air kerma rate of an ultra-soft X-ray beam (E = 1.5 keV). The size of the IC was determined so that the measurement volume satisfies the condition of charged-particle equilibrium. The correction factors nec-essary to properly measure the absolute kerma using the IC have been established. Particular attention was given to the determination of the effective mean energy 15 for the 1.5 keV photons using the PENELOPE code. Other correction factors were determined by means of computer simulation (COMSOL and FLUKA). Measure-ments of air kerma rates under specific operating parameters of the lab-bench X-ray source have been performed at various distances from that source and compared to Monte-Carlo calculations. We show that the developed ionization chamber makes it 20 possible to determine accurate photon fluence rates in routine work and will consti-tute substantial time-savings for future radiobiological experiments based on the use of ultra-soft X-rays.

International audience; The aim of this work is to characterize the Ultra Soft X-ray (USX, 1.5 keV, Al Kα) photon beam of a customized lab bench cold cathode generator. Within this generator, the electron beam is slowed down in a thin aluminium foil (16 μm) supported by an easily exchangeable anode. It is shown that the thickness of the foil and the anode configuration determine the spatial distribution and the fluence rate of the photon beam, whereas accelerating voltage determines both fluence rate and energy spectrum feature. It is shown also that under specific operation parameters (i.e. accelerating voltage), a Gaussian energy distribution of the beam can be generated which is centred on the energy of the Al Kα line (1.5 keV). Dosimetric films of GAFCHROMIC® HD-810 were used to estimate the photon fluence rate distribution of the beam. Its variation, when the generator acts as a monoenergetic source, was characterized with the two different configurations of the anode assembly. Finally, it is verified that the anode assembly consisting in a flat washer, on which the aluminium foil is set, acts as a simple point-source.

International audience; A paleomagnetic study has been conducted on intrusive doleritic rocks cropping out within Devonian horizontal tabular formations of the Saharan craton (Tin Serririne basin, South of Hoggar shield). The 40K/40Ar dating of the dolerites gave an age of 347.6 ± 8.1 Ma, i.e. Tournaisian. The paleomagnetic data present three different directions. The first has a paleomagnetic pole close to the previous African poles of Permian age. This direction is therefore interpreted as a Permian remagnetization. The second direction, which is defined by both linear regression and remagnetization circles analysis, is considered as the primary magnetization. It yields a new African Tournaisian paleomagnetic pole (λ = 18.8° S, phi = 31.2° E, K = 29, A95 = 7.5°) very close to the Ben Zireg Tounaisian pole [Aifa, T., Feinberg, H., Pozzi, J.P., 1990. Devonian/Carboniferous paleopoles for Africa. Consequences for Hercynian geodynamics. Tectonophysics, 179, 288–304]. The third direction has intermediate orientation between those of the first or second directions and that of the Upper Cenozoic field. It is interpreted as related to a composite magnetization. This new Tin Serririne pole improves the APWP of Gondwana, for this key period of the evolution of the Pangea. This APWP confirms the previous paleogeographic reconstruction which shows that the pre-Hercynian ocean between Gondwana and Laurussia is still not close during the beginning of the Carboniferous.

International audience; Âge 40K/40Ar, Carbonifère inférieur, du magmatisme basique filonien du synclinal paléozoïque de Tin Serririne, Sud-Est du Hoggar (Algérie) Lower Carboniferous 40K/40Ar dating of intrusive basic magmatism of the Paleozoic syncline of Tin Serririne, southeastern Hoggar (Algeria) Les séries primaires des Tassilis Oua-n-Ahaggar (Sud-Est du Hoggar) exposent, dans le synclinal de Tin Serririne, des passées magmatiques basiques alcalines. Le léger métamorphisme de contact qui affecte la couche les recouvrant et des études d'anisotropie de susceptibilité magnétique de ces dolérites ont permis de préciser que ces dernières correspondaient à des sills et à des dykes. Les datations 40K/40Ar d'un échantillon sur roche totale et sur feldspaths séparés et de deux autres échantillons sur roche totale se recoupent à Click to view the MathML source (pour Click to view the MathML source), indiquant de ce fait un âge qui correspond au Carbonifère inférieur (Tournaisien). La prise en compte de l'âge de ce magmatisme et des données stratigraphiques et structurales sur ce secteur suggèrent une mise en place de ces magmas au cours d'une distension liée au rejeu d'accidents tardi-panafricains. Pour citer cet article : H. Djellit et al., C. R. Geoscience 338 (2006).

Despite their proximity to the coast, few studies have focused on identifying and mapping the vegetation of Algerian islands and islets. To fill this lacuna, our work, using satellite images and machine learning methods, is mainly aimed at identifying and mapping the main vegetation groups on a few islands, while evaluating the effectiveness of the random forest classifier, which is effectively used in the study of the vegetation of large areas. However, despite the high heterogeneity of their vegetation cover, the use of very high-resolution images (Pleaides and SPOT 6/7), through the fusion bands and derived bands (NDVI), has allowed the elaboration of a fairly precise vegetation map that can be used for the preparation of management and protection plans for these habitats. Our methodological approach revealed very satisfactory results, having allowed the identification of the plant communities inventoried in the field, while showing high accuracy values, ranging from 0.642 for the halophilic group of Asteriscus to 1 for the endemic Chasmophyte group of the Habibas archipelago (Pleiades images). The groups identified from SPOT 6/7 images show accuracy values between 0.67 for the Mediterranean cliff formations on Garlic Islet and 1 for the two formations (shrubby and herbaceous) of the Skikda islands. Our methodological approach, and notwithstanding the great heterogeneity and the very small surface areas of our islands and islets, has led to very satisfactory results, reflected with good overall accuracy and kappa index values (for Pleiades: overall accuracy > 92% and kappa index > 0.90; for SPOT 6/7: overall accuracy > 83% and kappa index > 0.80).

International audience; We address with this paper some real-life healthy and epileptic EEG signals classification. Our proposed method is based on the use of the discrete wavelet transform (DWT) and Support Vector Machine (SVM). For each EEG signal, five wavelet decomposition level is applied which allow obtaining five spectral sub-bands correspond to five rhythms (Delta, Theta, Alpha, Beta and gamma). After the extraction of some features on each sub-band (energy, standard deviation, and entropy) a moving average (MA) is applied to the resulting features vectors and then used as inputs to SVM to train and test. We test the method on EEG signals during two datasets: normal and epileptics, without and with using MA to compare results. Three parameters are evaluated such as sensitivity, specificity, and accuracy to test the performances of the used methods.

International audience; Ultrathin layers (

International audience; We present an approach to elicit experts' knowledge about the Bliss model (Grollemund et al. 2018) which is a parsimonious Bayesian Functional Linear Regression model. We derive an informative prior from elicited information and we define weights to tune prior information contribution on the estimators.

International audience; Energy harvesting technologies are required for autonomous applications, like sensors, for which a long-time power sourcing from a battery is infeasible. An energy harvester converts different forms of environmental energy into electricity. It can replace, totally or partially, the batteries of certain micro-systems that have low-energy requirements. Therefore, the authors exploit the use of electromagnetic waves from broadcasters to power wireless sensors. The authors propose to realize harvesting operation at typical ambient radio frequency power levels found within urban environments. To explore the potential for ambient RF energy harvesting, an RF spectral survey was undertaken from outside in Paris. The average RF power in the frequency range 0.9-3 GHz is about −12 dBm. The harvester includes an antenna, an impedance-matching network, and a rectifier; it was designed to cover two frequency bands from the largest RF contributors (GSM1800 and UMTS Band 1). A prototype is designed, fabricated, and measured. The RF-to-DC rectifier and the choice of the load to optimize the amount of DC power are presented. An efficiency of ∼45% was observed experimentally for the UMTS Band 1 and 33% for the GSM1800, whenever the incident power is −7 dBm. Numerical and experimental data are reported and discussed

BPH and prostate cancer are the two most prevalent prostatic diseases in elders. Understanding their etiology and pathogenesis is necessary in order to prevent them and to enhance both research and development of new therapeutic agents. Our goal is to study the implication of oxidative stress in BPH and to study the effect of propolis extract on prostate cancer in vivo in Wistar rats and in vitro on LNCaP cells. We have shown that: 1) Oxidative stress acts as a promoter in the development of BPH, 2) Benzo(a)pyrene administered to Wistar rats induces the development of prostate cancer, 3) Propolis induces a decrease in proliferation, Ki-67 expression (-49%) and AhR expression in the Wistar rat, (4) Propolis has an antiproliferative effect on LNCaP cells via AR signaling blockade.; L’HBP et le cancer de la prostate constituent les deux maladies prostatiques les plus répandues chez l’homme âgé. La compréhension de leur étiologie et de leur pathogenèse est nécessaire afin de permettre la prévention mais aussi la recherche et le développement de nouveaux agents thérapeutiques. Notre but est d’étudier l’implication du stress oxydatif dans l’HBP et d’étudier l’effet de l’extrait de propolis sur le cancer de la prostate in vivo chez le rat Wistar et in vitro sur les cellules LNCaP. Nous avons montré que : 1) Le stress oxydatif joue le rôle de promoteur dans le développement de l’HBP, 2) Le benzo(a)pyrène administré aux rats Wistar induit le développement du cancer de la prostate, 3) La propolis induit la diminution de la prolifération, de l’expression du Ki-67 (-49 %) et de l’expression de AhR chez le rat Wistar, 4) La propolis possède un effet antiprolifératif sur les cellules LNCaP via le blocage de la signalisation de AR.

BPH and prostate cancer are the two most prevalent prostatic diseases in elders. Understanding their etiology and pathogenesis is necessary in order to prevent them and to enhance both research and development of new therapeutic agents. Our goal is to study the implication of oxidative stress in BPH and to study the effect of propolis extract on prostate cancer in vivo in Wistar rats and in vitro on LNCaP cells. We have shown that: 1) Oxidative stress acts as a promoter in the development of BPH, 2) Benzo(a)pyrene administered to Wistar rats induces the development of prostate cancer, 3) Propolis induces a decrease in proliferation, Ki-67 expression (-49%) and AhR expression in the Wistar rat, (4) Propolis has an antiproliferative effect on LNCaP cells via AR signaling blockade.; L’HBP et le cancer de la prostate constituent les deux maladies prostatiques les plus répandues chez l’homme âgé. La compréhension de leur étiologie et de leur pathogenèse est nécessaire afin de permettre la prévention mais aussi la recherche et le développement de nouveaux agents thérapeutiques. Notre but est d’étudier l’implication du stress oxydatif dans l’HBP et d’étudier l’effet de l’extrait de propolis sur le cancer de la prostate in vivo chez le rat Wistar et in vitro sur les cellules LNCaP. Nous avons montré que : 1) Le stress oxydatif joue le rôle de promoteur dans le développement de l’HBP, 2) Le benzo(a)pyrène administré aux rats Wistar induit le développement du cancer de la prostate, 3) La propolis induit la diminution de la prolifération, de l’expression du Ki-67 (-49 %) et de l’expression de AhR chez le rat Wistar, 4) La propolis possède un effet antiprolifératif sur les cellules LNCaP via le blocage de la signalisation de AR.

International audience; Phonocardiogram signals (PCGs) represent a nonstationary signal due to their complicated production. Also, during the registration they may be added with different noise and pathological murmurs. Indeed, in real situation, the heart sound signal (HSs) may present some abnormal murmur characterizing a variety of heart diseases. This work deals with the segmentation of pathological PCGs based on the Discrete Wavelet Transform (DWT) which permits signal decomposition in different frequency bands. After the decomposition step, we estimate the Renyi Entropy (RE) of the detail coefficients. Then, we apply a threshold allowing detecting the murmur of the PCGs. After the detection, we characterize the results in time–frequency domain in order to extract some features such as frequency band, peak frequency and time duration of the abnormal murmur. The validation of the method is evaluated and proved using some pathological PCGs such as: Early Aortic Stenosis (EAS), Late Aortic Stenosis (LAS), Mitral Regurgitation (MR), Aortic Regurgitation (AR), Opening Snap (OS) and Pulmonary Stenosis (PS). The method presents good results in terms of the detection and the characterization of the main components and the abnormal murmurs associated with some valves disease.

This thesis focuses on the control part of robotic navigation. The objective is to propose new algorithms to contribute to the problem of motion control of mobile robot manipulators. This work is of interest in the design and real-time execution of a new intelligent, autonomous and more generic control algorithm, it has interesting advantages whose ease of implementation with the least knowledge about the system to be controlled, and does not require the know-how of a qualified user for implementation and parameterization. It mainly comprises two levels; a mechanism based on the fuzzy system and a modified algorithm of the ant colonies for the autonomous adjustment of the various parameters of a control law, and which provides a speed of computation in real time and a flexibility of executing in-line with the control law. And another level for the control law, by choosing a new hybrid approach, whichcombines a part of the optimal control, adaptive neural control, and robust adaptive control. In this sense, the algorithm goes beyond the simple role of control and optimization, and can be considered not only as another law to control with some robustness an unknown dynamic system but as a considerable extension which covers the most general case of the implementation of a control law and their parameterization; Cette thèse s'intéresse à la partie commande de la navigation robotique. L'objectif est de proposer de nouveaux algorithmes pour contribuer au problème de commande des mouvements des robots manipulateurs mobiles. Ce travail trouve son intérêt dans la conception et l'exécution en temps réel d’un nouvel algorithme de contrôle intelligent,autonome et plus générique, possède des avantages intéressants dont la facilité d’implémentation avec la moindre connaissance sur le système à commander, et ne nécessite pas le savoir-faire d’un utilisateur qualifié pour l’implémentation et le paramétrage. Il comprend principalement deux niveaux; un mécanisme basé sur le système flou et un algorithme modifié des colonies de fourmis pour le réglage autonome des différents paramètres d’une loi de commande, et qui dispose une rapidité de calcul en temps réel et une souplesse de la mise en ligne avec la loi de commande ; et un autre niveau destiné à la loi de commande en choisissant une nouvelle approche hybride, qui combine une partie de la commande optimale, la commande neuronale adaptative, et la commande robuste adaptative. Dans ce sens, l’algorithme dépasse le simple rôle de commande et d’optimisation et peut être considérée non seulement comme une autre loi pour commander avec une certaine robustesse un système dynamique inconnu, mais comme une extension considérable qui couvre le cas le plus général de l’implémentation d’une loi de commande et leur paramétrage.

This thesis focuses on the control part of robotic navigation. The objective is to propose new algorithms to contribute to the problem of motion control of mobile robot manipulators. This work is of interest in the design and real-time execution of a new intelligent, autonomous and more generic control algorithm, it has interesting advantages whose ease of implementation with the least knowledge about the system to be controlled, and does not require the know-how of a qualified user for implementation and parameterization. It mainly comprises two levels; a mechanism based on the fuzzy system and a modified algorithm of the ant colonies for the autonomous adjustment of the various parameters of a control law, and which provides a speed of computation in real time and a flexibility of executing in-line with the control law. And another level for the control law, by choosing a new hybrid approach, whichcombines a part of the optimal control, adaptive neural control, and robust adaptive control. In this sense, the algorithm goes beyond the simple role of control and optimization, and can be considered not only as another law to control with some robustness an unknown dynamic system but as a considerable extension which covers the most general case of the implementation of a control law and their parameterization; Cette thèse s'intéresse à la partie commande de la navigation robotique. L'objectif est de proposer de nouveaux algorithmes pour contribuer au problème de commande des mouvements des robots manipulateurs mobiles. Ce travail trouve son intérêt dans la conception et l'exécution en temps réel d’un nouvel algorithme de contrôle intelligent,autonome et plus générique, possède des avantages intéressants dont la facilité d’implémentation avec la moindre connaissance sur le système à commander, et ne nécessite pas le savoir-faire d’un utilisateur qualifié pour l’implémentation et le paramétrage. Il comprend principalement deux niveaux; un mécanisme basé sur le système flou et un algorithme modifié des colonies de fourmis pour le réglage autonome des différents paramètres d’une loi de commande, et qui dispose une rapidité de calcul en temps réel et une souplesse de la mise en ligne avec la loi de commande ; et un autre niveau destiné à la loi de commande en choisissant une nouvelle approche hybride, qui combine une partie de la commande optimale, la commande neuronale adaptative, et la commande robuste adaptative. Dans ce sens, l’algorithme dépasse le simple rôle de commande et d’optimisation et peut être considérée non seulement comme une autre loi pour commander avec une certaine robustesse un système dynamique inconnu, mais comme une extension considérable qui couvre le cas le plus général de l’implémentation d’une loi de commande et leur paramétrage.

Bayesian Functional Linear Regression with Informative Prior Distribution . 49. Journées de Statistique de la SFdS

International audience; A well-type detector installed in the Modane underground Laboratory (LSM) can combine both low background and high detection efficiency and it is well suited for the analysis of small amounts of environmental samples. Reference materials such as IAEA-447 (moss-soil), IAEA-RG-Th1 and IAEA-RG-U1 were used for the detector calibration, owing to a chemical composition close to those of the environmental samples. Nevertheless , the matrix effects and the true coincidence summing effects must be corrected from the full energy peak efficiency (FEPE). The FEPE was performed for a wide range of energy by a semi-empirical method using Monte Carlo simulation (MCNP6), intended for environmental measurements such as lake sediments dating. In the well geometry, the true coincidence summing effects could be very important and correction factors have been computed in three different ways.

This study focuses on new fossil faunas of bats discovered in North Africa following several field campaigns. The fossiliferous localities include those from the Early to Middle Eocene of Tunisia (Chambi) and Algeria (Glib Zegdou). Systematic and cladistic analyses carried out on the fossil material, primarily including isolated teeth, allow us to highlight the modalities of the radiation of the first modern microbats. These new faunas include eight well-identified new taxa belonging to five modern families: one Necromantidae (?Necromantis fragmentum Ravel, n. sp.), two Hipposideridae Miller, 1907 (?Palaeophyllophora tunisiensis Ravel, n. sp. and Hipposideros [Pseudorhinolophus] africanum Ravel, n. sp.), three Emballonuridae Gervais in de Castelnau, 1855 (Vespertiliavus kasserinensis Ravel, n. sp., ?Vespertiliavus aenigma Ravel, n. sp., and Pseudovespertiliavus parva Ravel n. gen., n. sp.), one Nycteridae (Khoufechia gunnelli Ravel n. gen., n. sp.) and an undetermined Vespertilionidae. Two other taxa are identified (Chambinycteris pusilli Ravel n. gen., n. sp. and Drakonycteris glibzegdouensis Ravel n. gen., n. sp.), but they show an original dental pattern which precludes a family attribution. Two cladistic analyses allow to clarify the phylogenetic position of the best documented taxa. The results highlight for Hipposideridae and Emballonuridae chiropterans a major dispersal axis from North Africa towards South Europe during the Middle Eocene.

Interpretable Bayesian Functional Linear Regression. 47. Journées de Statistique de la SFdS

This paper presents a method to characterize, identify and classify some pathological Electroencephalogram (EEG) signals. We use some Time Frequency Distributions (TFDs) to analyze its nonstationarity. The analysis is conducted by the spectrogram (SP), the Choi–Williams Distribution (CWD) and the Smoothed Pseudo Wigner Ville Distribution (SPWVD). The studies are carried on some real EEG signals collected from a known database. The estimation of the best value of parameters for each distribution is achieved using the Rényi entropy (RE). The time-frequency results have permitted to characterize some pathological EEG signals. In addition, the Rényi Marginal Entropy (RME) is used for the purpose of detecting the peak seizures and discriminates between normal and pathological EEG signals. The frequency bands are evaluated using the Marginal Frequency (MF). The EEG signal classification of two sets A and E containing normal and pathologic EEG signals, respectively, is performed using our proposed method based on energy extraction of signals from time-frequency plane. Also, the Moving Average (MA) is used as a tool to obtain better classification results. The results conducted on real-life EEG signals illustrate the effectiveness of the proposed method.

Higher order corrections in gauge theories play a crucial role in studying physics within the standard model and beyond at TeV colliders, like LHC, TeVatron and ILC. Therefore, it is of extreme importance to provide tools for next-to-leading order amplitude computation which are fast, stable, efficient and highly automatized. This thesis aims at developing the library of integrals Golem95. This library is a program written in Fortran95, it contains all the necessary ingredients to calculate any one-loop scalar or tensorial integral with up to six external legs. Golem95 uses the traditional reduction method (Golem reduction) to reduce the form factors into redundant basic integrals, which can be scalar (without Feynman parameters in the numerator) or tensorial (with Feynman parameter in the numerator); this formalism allows us to avoid the problems of numerical instabilities generated by the spurious singularities induced by the vanishing of the Gram determinants. In addition, this library can be interfaced with automatic programs of NLO calculation based on the unitarity inspired reduction methods as GoSam for example. Earlierversions of Golem95 were designed for the calculation of amplitudes without internal masses. The purpose of this thesis is to extend this library for more general configurations (complex masses are supported); and to provide numerically stable calculation in the problematic regions (det(G) → 0), by providing a stable one-dimensional integral representation for each Golem95 basic integral., Les calculs de précision dans les théories de jauge jouent un rôle très important pour l’étude de la physique du Modèle Standard et au-delà dans les super-collisionneurs de particules comme le LHC, TeVatron et ILC. Par conséquent, il est extrêmement important de fournir des outils du calcul d’amplitudes à une boucle stables, rapides, efficaces et hautement automatisés. Cette thèse a pour but de développer la bibliothèque d’intégrales Golem95. Cette bibliothèque est un programme écrit en Fortran95, qui contient tous les ingrédients nécessaires pour calculer une intégrale scalaire ou tensorielle à une boucle avec jusqu’à six pattes externes. Golem95 utilise une méthode traditionnelle de réduction (réduction à la Golem) qui réduit les facteurs de forme en des intégrales de base redondantes qui peuvent être scalaires (sans paramètres de Feynman au numérateur) ou tensorielles (avec des paramètres de Feynman au numérateur); ce formalisme permet d’éviter les problèmes de l’instabilité numérique engendrés par des singularités factices dues à l’annulation des déterminants de Gram. En plus, cette bibliothèque peut être interfacée avec des programmes du calcul automatique basés sur les méthodes d’unitarité comme GoSam par exemple. Les versions antérieures de Golem95 ont été conçues pour le calcul des amplitudes sans masses internes. Le but de ce travail de thèse est de généraliser cette bibliothèque pour les configurations les plus générales (les masses complexes sont incluses), et de fournir un calcul numériquement stable dans les régions problématique en donnant une représentation intégrale unidimensionnelle stable pour chaque intégrale de base de Golem95.

Higher order corrections in gauge theories play a crucial role in studying physics within the standard model and beyond at TeV colliders, like LHC, TeVatron and ILC. Therefore, it is of extreme importance to provide tools for next-to-leading order amplitude computation which are fast, stable, efficient and highly automatized. This thesis aims at developing the library of integrals Golem95. This library is a program written in Fortran95, it contains all the necessary ingredients to calculate any one-loop scalar or tensorial integral with up to six external legs. Golem95 uses the traditional reduction method (Golem reduction) to reduce the form factors into redundant basic integrals, which can be scalar (without Feynman parameters in the numerator) or tensorial (with Feynman parameter in the numerator); this formalism allows us to avoid the problems of numerical instabilities generated by the spurious singularities induced by the vanishing of the Gram determinants. In addition, this library can be interfaced with automatic programs of NLO calculation based on the unitarity inspired reduction methods as GoSam for example. Earlierversions of Golem95 were designed for the calculation of amplitudes without internal masses. The purpose of this thesis is to extend this library for more general configurations (complex masses are supported); and to provide numerically stable calculation in the problematic regions (det(G) → 0), by providing a stable one-dimensional integral representation for each Golem95 basic integral.; Les calculs de précision dans les théories de jauge jouent un rôle très important pour l’étude de la physique du Modèle Standard et au-delà dans les super-collisionneurs de particules comme le LHC, TeVatron et ILC. Par conséquent, il est extrêmement important de fournir des outils du calcul d’amplitudes à une boucle stables, rapides, efficaces et hautement automatisés. Cette thèse a pour but de développer la bibliothèque d’intégrales Golem95. Cette bibliothèque est un programme écrit en Fortran95, qui contient tous les ingrédients nécessaires pour calculer une intégrale scalaire ou tensorielle à une boucle avec jusqu’à six pattes externes. Golem95 utilise une méthode traditionnelle de réduction (réduction à la Golem) qui réduit les facteurs de forme en des intégrales de base redondantes qui peuvent être scalaires (sans paramètres de Feynman au numérateur) ou tensorielles (avec des paramètres de Feynman au numérateur); ce formalisme permet d’éviter les problèmes de l’instabilité numérique engendrés par des singularités factices dues à l’annulation des déterminants de Gram. En plus, cette bibliothèque peut être interfacée avec des programmes du calcul automatique basés sur les méthodes d’unitarité comme GoSam par exemple. Les versions antérieures de Golem95 ont été conçues pour le calcul des amplitudes sans masses internes. Le but de ce travail de thèse est de généraliser cette bibliothèque pour les configurations les plus générales (les masses complexes sont incluses), et de fournir un calcul numériquement stable dans les régions problématique en donnant une représentation intégrale unidimensionnelle stable pour chaque intégrale de base de Golem95.

ATP-sensitive potassium channels (KATP) play an important role in many cellular processes. The modulation of these channels by activating molecules may constitute very interesting pharmacological and medicinal applications. For this purpose, we have designed and synthesized new hybrid molecules cromakalim-diazoxide and diazoxide-amine/aminoacid. We also evaluated the relaxant activity of these compounds on aorta of rats. The obtained results do not show a significant relaxant effect. Studies on other tissues, including pancreatic  cells and uterine muscle, are envisaged to explore the potency of these compounds and their possible tissue selectivity.Otherwise, Protein-protein interactions play a fundamental role in almost all cellular processes. They are strongly involved in the formation of the dimeric structure of HIV-1 protease and β amyloid peptide aggregation involved in Alzheimer's disease. Inhibition of these interactions would be a therapeutic advantage for the treatment of AIDS and Alzheimer's disease. We designed and synthesized on one hand, molecular tongs based on carbonylhydrazide oligohydrazid (Azatide) fragments and in the other hand, pentapeptide molecules with a central fluorinated and hydroxylated aminoacid. Finally, we tested the ability of molecular tongs to disrupt the terminal β sheet of the HIV-1 PR to inhibit its dimerization and thus its activity. We have also conducted a structure-activity relationship study and According to the results it seems that flexibility is detrimental to the inhibitory activity. We evaluated as well the ability of new fluorinated and hydroxylated peptidomimetics to accelerate or inhibit the aggregation of Aβ1-42 peptide in order to reduce the presence of small toxic oligomers. The results are very promising that we succeeded in developing a pentapeptide able to completely inhibit the aggregation of Aβ1-42, and in the other hand pseudopentapeptides able to accelerate its aggregation. We also demonstrated the influence of fluorine on the structure of a pentapeptides. Studies by NMR and DC are in progress.; Les canaux potassiques sensibles à l’ATP (KATP) jouent un rôle primordial dans plusieurs processus cellulaires. La modulation de ces canaux par des molécules activatrices constituerait des applications pharmacologiques et médicinales très intéressantes. À cet effet nous avons conçu et synthétisé de nouvelles molécules hybrides cromakalim-diazoxide et diazoxide-amine/aminoacide. Nous avons également, évalué l’activité myorelaxante de ces composés sur l’aorte de rates. Les résultats obtenus ne montrent pas un effet myorelaxant significatif. Des études sur d’autres tissus, notamment les cellules β pancréatiques et le muscle utérin, sont envisagées afin d’explorer une éventuelle sélectivité tissulaire. Par ailleurs, les interactions protéine-protéine jouent un rôle fondamental dans presque tous les processus cellulaires. Elles sont fortement impliquées dans la formation de la structure dimérique de la protéase du VIH-1 et l’agrégation du peptide β amyloïde impliquée dans la maladie d’Alzheimer. L’inhibition de ces interactions serait donc d’un avantage thérapeutique pour le traitement du SIDA et de la maladie d’Alzheimer. Nous avons conçu et synthétisé d’une part, des pinces moléculaires à base de motifs carbonylhydrazides et oligohydrazides (Azatide), et d’autre part, des molécules pentapeptidiques avec un peudoaminoacide central alcoolfluoré. Enfin, nous avons testé la capacité des pinces moléculaires à perturber le feuillet β terminal de la PR du VIH-1 afin d'inhiber sa dimérisation et donc son activité. Nous avons réalisé de même une étude de relation structure-activité et d’après l’ensemble des résultats obtenus, il semblerait que la flexibilité est délétère pour l’activité inhibitrice. Nous avons également évalué la capacité des nouvelles molécules peptidomimétiques alcool fluorées à accélérer ou inhiber l’agrégation du peptide Aβ1-42 dans le but de diminuer la présence de petits oligomères neurotoxiques. Les résultats obtenus sont très prometteurs, nous avons réussi à développer d’une part un pentapeptide capable d’inhiber totalement l’agrégation de Aβ1-42, et d’autre part des pseudopentapeptides capables d’accélérer son agrégation. Nous avons aussi démontré l’influence de l’atome de fluor sur la structuration d’un pentapeptide. Des études par RMN et DC sont en cours.

ATP-sensitive potassium channels (KATP) play an important role in many cellular processes. The modulation of these channels by activating molecules may constitute very interesting pharmacological and medicinal applications. For this purpose, we have designed and synthesized new hybrid molecules cromakalim-diazoxide and diazoxide-amine/aminoacid. We also evaluated the relaxant activity of these compounds on aorta of rats. The obtained results do not show a significant relaxant effect. Studies on other tissues, including pancreatic  cells and uterine muscle, are envisaged to explore the potency of these compounds and their possible tissue selectivity.Otherwise, Protein-protein interactions play a fundamental role in almost all cellular processes. They are strongly involved in the formation of the dimeric structure of HIV-1 protease and β amyloid peptide aggregation involved in Alzheimer's disease. Inhibition of these interactions would be a therapeutic advantage for the treatment of AIDS and Alzheimer's disease. We designed and synthesized on one hand, molecular tongs based on carbonylhydrazide oligohydrazid (Azatide) fragments and in the other hand, pentapeptide molecules with a central fluorinated and hydroxylated aminoacid. Finally, we tested the ability of molecular tongs to disrupt the terminal β sheet of the HIV-1 PR to inhibit its dimerization and thus its activity. We have also conducted a structure-activity relationship study and According to the results it seems that flexibility is detrimental to the inhibitory activity. We evaluated as well the ability of new fluorinated and hydroxylated peptidomimetics to accelerate or inhibit the aggregation of Aβ1-42 peptide in order to reduce the presence of small toxic oligomers. The results are very promising that we succeeded in developing a pentapeptide able to completely inhibit the aggregation of Aβ1-42, and in the other hand pseudopentapeptides able to accelerate its aggregation. We also demonstrated the influence of fluorine on the structure of a pentapeptides. Studies by NMR and DC are in progress., Les canaux potassiques sensibles à l’ATP (KATP) jouent un rôle primordial dans plusieurs processus cellulaires. La modulation de ces canaux par des molécules activatrices constituerait des applications pharmacologiques et médicinales très intéressantes. À cet effet nous avons conçu et synthétisé de nouvelles molécules hybrides cromakalim-diazoxide et diazoxide-amine/aminoacide. Nous avons également, évalué l’activité myorelaxante de ces composés sur l’aorte de rates. Les résultats obtenus ne montrent pas un effet myorelaxant significatif. Des études sur d’autres tissus, notamment les cellules β pancréatiques et le muscle utérin, sont envisagées afin d’explorer une éventuelle sélectivité tissulaire. Par ailleurs, les interactions protéine-protéine jouent un rôle fondamental dans presque tous les processus cellulaires. Elles sont fortement impliquées dans la formation de la structure dimérique de la protéase du VIH-1 et l’agrégation du peptide β amyloïde impliquée dans la maladie d’Alzheimer. L’inhibition de ces interactions serait donc d’un avantage thérapeutique pour le traitement du SIDA et de la maladie d’Alzheimer. Nous avons conçu et synthétisé d’une part, des pinces moléculaires à base de motifs carbonylhydrazides et oligohydrazides (Azatide), et d’autre part, des molécules pentapeptidiques avec un peudoaminoacide central alcoolfluoré. Enfin, nous avons testé la capacité des pinces moléculaires à perturber le feuillet β terminal de la PR du VIH-1 afin d'inhiber sa dimérisation et donc son activité. Nous avons réalisé de même une étude de relation structure-activité et d’après l’ensemble des résultats obtenus, il semblerait que la flexibilité est délétère pour l’activité inhibitrice. Nous avons également évalué la capacité des nouvelles molécules peptidomimétiques alcool fluorées à accélérer ou inhiber l’agrégation du peptide Aβ1-42 dans le but de diminuer la présence de petits oligomères neurotoxiques. Les résultats obtenus sont très prometteurs, nous avons réussi à développer d’une part un pentapeptide capable d’inhiber totalement l’agrégation de Aβ1-42, et d’autre part des pseudopentapeptides capables d’accélérer son agrégation. Nous avons aussi démontré l’influence de l’atome de fluor sur la structuration d’un pentapeptide. Des études par RMN et DC sont en cours.

Published online in Wiley Online Library (wileyonlinelibrary.com).; International audience; A thermodynamic description of liquid flows in capillaries with hydrodynamic slip at the solid–liquid interface is given. Slip over the capillary wall brings into play surface interactions and therefore involves interfacial energy and entropy. Energy and entropy balance equations are written so as to take into account surface effects. The two relations constitute a general mathematical model that allows readily analyzing various situations and to explore the behavior of such thermodynamic process. The main result derived concerns the existence of a capillary pressure of slip; slip occurrence leads to a pressure decrease in the flow and might cause cavitation. The variation in magnitude of the slip effect, viewed as a thermodynamic transformation, may take place irreversibly. Slip irreversibility and the probable occurrence of a two-phase flow regime are possible factors that may cause additional pressure drop.

Recent fossil discoveries have demonstrated that Africa and Asia were epicentres for the origin and/or early diversification of the major living primate lineages, including both anthropoids (monkeys, apes and humans) and crown strepsirhine primates (lemurs, lorises and galagos). Competing hypotheses favouring either an African or Asian origin for anthropoids rank among the most hotly contested issues in paleoprimatology. The Afrocentric model for anthropoid origins rests heavily on the >45 Myr old fossil Algeripithecus minutus from Algeria, which is widely acknowledged to be one of the oldest known anthropoids. However, the phylogenetic position of Algeripithecus with respect to other primates has been tenuous because of the highly fragmentary fossils that have documented this primate until now. Recently recovered and more nearly complete fossils of Algeripithecus and contemporaneous relatives reveal that they are not anthropoids. New data support the idea that Algeripithecus and its sister genus Azibius are the earliest offshoots of an Afro–Arabian strepsirhine clade that embraces extant toothcombed primates and their fossil relatives. Azibius exhibits anatomical evidence for nocturnality. Algeripithecus has a long, thin and forwardly inclined lower canine alveolus, a feature that is entirely compatible with the long and procumbent lower canine included in the toothcomb of crown strepsirhines. These results strengthen an ancient African origin for crown strepsirhines and, in turn, strongly challenge the role of Africa as the ancestral homeland for anthropoids.

International audience; This contribution focuses on some non-classical aspects of capillary phenomena, mostly omitted in classical approaches, in particular the non-isothermal aspects. A systematic thermodynamic approach is proposed that allows a rigorous formulation of the governing equations in non-isothermal situations, by introducing the surface effects in the energy and entropy balances. The energetic quantities (work and heat) are calculated in a number of examples, such as adiabatic and isothermal wetting/dewetting of a porous medium, nanofluids heating, emulsion split, and new equilibrium criteria are derived were appropriate.