Le Librator Nonius Datus et l'aqueduc de Saldae

Malgré la fameuse réputation qui lui est faite depuis la découverte de l'inscription de Nonius Datus en 1866 à Lambèse, l'aqueduc de Saldae et son tunnel et ses ouvrages d'art n'ont jamais été documentés et étudiés convenablement. Si l'apport de ce texte est incommensurable pour ce qui est de la manière dont étaient montés les projets de grande envergure pendant l'époque romaine, et spécialement sur les procèdes techniques usités pour la tunnelisation des galeries souterraines ; il soulève toutefois-de part les péripéties et les retards pris dans sa réalisation – des problématiques propres à l'aqueduc de Saldae pour l'es aspects administratifs et juridiques et financiers, les aspects liés à la maitrise d'oeuvre notamment les opérations de nivellement et de calcul des pentes et en fin des problèmes et difficultés survenues lors du creuse-ment du tunnel d'El Habel, ou les deux équipes chargées de cette tâche n'arrivaient pas à faire jonction. La présente étude focalise sur les aspects relevant du nivellement général de l'aqueduc de Saldae par l'analyse des choix du Librator Nonius Datus et leur pertinence dans l'établissement du tracé et des ouvrages d'art retenus afin d' assurer par une succession de valeurs de pentes un écoulement sûr et réduire la longueur totale du conduit dans un souci de réduire les couts de réalisation

Joint unmixing-deconvolution algorithms for hyperspectral images

International audienceThis paper combines supervised linear unmixing and deconvolution problems to increase the resolution of the abundance maps for industrial imaging systems. The joint unmixing-deconvolution (JUD) algorithm is introduced based on the Tikhonov regularization criterion for offline processing. In order to meet the needs of industrial applications, the proposed JUD algorithm is then extended for online processing by using a block Tikhonov criterion. The performance of JUD is increased by adding a non-negativity constraint which is implemented in a fast way using the quadratic penalty method and fast Fourier transform. The proposed algorithm is then assessed using both simulated and real hyperspectral images

A simultaneous sparse approximation method for multidimensional harmonic retrieval

International audienceIn this paper, a new method for the estimation of the parameters of multidimensional (R-D) harmonic and damped complex signals in noise is presented. The problem is formulated as R simultaneous sparse approximations of multiple 1-D signals. To get a method able to handle large size signals while maintaining a sufficient resolution, a multigrid dictionary refinement technique is associated to the simultaneous sparse approximation. The refinement procedure is proved to converge in the single R-D mode case. Then, for the general multiple modes case, the signal tensor model is decomposed in order to handle each mode separately in an iterative scheme. The proposed method does not require an association step since the estimated modes are automatically "paired". We also derive the Cramér-Rao lower bounds of the parameters of modal R-D signals. The expressions are given in compact form in the single tone case. Finally, numerical simulations are conducted to demonstrate the effectiveness of the proposed method

Determination of the mineral profile of raw and roasted lentil flour after addition to yogurt

Introduction: Lentil (Lens culinaris) is a pulse largely consumed in the world, especially in Algeria. This legume can be consumed in different forms (pottage, soup), but also flour can be produced after roasting treatment of the lentils. Resulted flour can be used as a food or ingredient in the formulation of food products. Aims: The main objective of this study is to determine the variation in the main mineral content of lentil flour. The flour was analyzed at its native state (raw), after roasting, raw before addition to yogurt, and roasted after addition in yogurt as a functional ingredient at a rate of 4%. Material and Methods: The lentil flours analysis was carried out by means of Scanning Electron Microscopy (SEM) associated with Dispersive X-ray Energy (EDX) microanalysis (SEM-EDX). Results: The results show that the roasting treatment does not have a marked effect on the mineral content of lentil flours. However, the addition to the yogurt made it possible to raise the mineral content of the raw and roasted lentil flour remarkably. Conclusions: Adding lentil flour to yogurt is an effective way to increase the mineral content of yogurts made from these flours

Assessment of non-negative matrix factorization for the preprocessing of long-term ECG

Présentation PosterInternational audienceBackground. With the advent of health information technology and wearable acquisition systems, long-term ECG are more and more used in long-term cardiac tolerability studies of new compounds. Nevertheless, the accurate analysis of such long signals requires reliable and fast signal processing algorithms. Objectives. The objective of this study is to assess the practical relevance of innovative matrix factorization methods for the preprocessing of long-term ECG. Those signals are generally noisy with complex baseline wander and require preprocessing, such as filtering, to perform a correct analysis. Our goal is to present two innovative algorithms of matrix factorization to detect R-peaks in long-term ECG.Methods. The two tested methods are called Independent Component Analysis (ICA) and Non-Negative Matrix Factorization (NMF). They are both source separation methods whose goal is to isolate each component of an ECG: R-peak, P and T waves, noise, baseline wander etc. On the one hand, ICA assumes that all subcomponents of the signal are statistically independent from each other and on the other hand, Non-Negative Matrix Factorization is a method that uses the non-negativity of the spectrogram of the ECG to separate the different time-frequency patterns. The two signal processing methods were implemented in the Matlab computing environment.Results. The proposed approaches are tested on the MIT-BIH Arrythmia and Noise Stress Test databases: ICA shows a strong drawback by returning the different sources in a random order making compulsory a reconnaissance step or the action of a specialist. Whereas NMF achieves high results in terms of sensitivity and specificity in general even in case of complex baseline wander and highly noisy signals. Conclusion. This study emphasizes promising results of a new long-term ECG preprocessing technique based on a matrix factorization method. This approach simultaneously undertakes three tasks: denoising, baseline wander removal and peak R detection

Early detection of Cheyne-Stokes breathing via ECG-derived respiration in patients with severe heart failure: a pilot study

International audienceWe present in this paper a preliminary study for detecting early pattern of Cheyne-Stokes Breathing using a single electrocardiogram signal in patients with severe heart failure. Two ECG-derived respiration signals, namely Heart-Rate and R-Wave Amplitude, are computed and jointly used to estimate different respiratory events, respiratory rate and amplitude modulation. Three patients whose respiration goes from normal to severe CSB are used to test our method. Results show good performance for the detection of breathing cycles compared with the ventilation signal and the final classification based on respiratory events, AHI, amplitude modulation reveals exact correlation with the expert

R-peak detection in holter ECG signals using non-negative matrix factorization

International audienceHolter monitoring is mainly used for medical follow- up and diagnosis of patients with suspected cardiac ar- rhythmia such as heart rhythm irregularities that can be missed during classical electrocardiogram recording (ECG). However, these long-term continuous recordings represent a large amount of data that cannot be processed by hand. In this article, we present a new method based on Non-negative Matrix Factorization (NMF) to detect R- peaks in Holter signals. The approach consists in two stages: source separation based on the different time- frequency patterns of the QRS complexes and the other waves of the signal (P and T waves) and R-peak detection using Automatic Objective Thresholding (AOT). The pro- posed approach is validated on the MIT-BIH Arrhythmia database and achieves an average sensitivity of 99.59% and a precision of 99.69%. Using the MIT-BIH Noise Stress Test database, we also show the ability of our ap- proach to discriminate R-peaks in signals contaminated with different noises

Transgenerational effects of ERalpha36 over-expression on mammary gland development and molecular phenotype: clinical perspective for breast cancer risk and therapy.

International audienceGrowing source of evidence suggests that exposure to estrogen mimicking agents is a risk factor for breast cancer onset and progression. Long chain alkylphenols are man made compounds still present in household products, industrial and agricultural processes, leading to a global environmental and human contamination. These molecules are known to exert estrogen -like activities through binding to classical estrogen receptors. Recently, we have demonstrated that a realistic mixture of 4 tert - octylphenol and 4 - nonylphenol can stimulate proliferation and modulate epigenetic status of testicular cancer germ cells through a rapid, Estrogen Receptor alpha 36 (ERα36) -dependent non genomic pathway (Ajj et al, 2013; doi: 10.1371/journal.pone.0061758). In a retrospective study of breast tumor samples, we also validated ERα36 expression as a reliable prognostic factor for cancer progression from an estrogen dependent prolifera tive tumor toward an estrogen dispensable metastatic disease (Chamard - Jovenin et al, 2015; doi: 10.1186/s12918 - 015 - 0178 - 7). Since high ERα36 expression enhances expression of migration/invasion markers in breast tumors, we addressed the question of its involvement in response to alkylphenol exposure in vitro (MCF -10A mammary epithelial cell line and MCF -7 estrogen -sensitive cancer cells) and in vivo ( C57BL mice). A male inherited transgenerational model of exposure to environmentally relevant doses of an alkylphenol mix was set up in C57BL/6J mice to determine whether and how it impacts on mammary gland morphogenesis. Human mammary epithelial MCF -10A cells were exposed to similar doses to decipher the molecular mechanisms involved by a combination of transcriptomic study, cell phenotype analyses, functional and signaling network modeling. The relevance of mouse phenotype extrapolation to human risk is discussed. Mouse mammary gland exposed transgenerationally to the alkylphenol mix displayed a neoplastic -like histology. This phenotype was correlated with the enhanced proliferation, migration ability and apoptosis resistance observed in vitro on human mammary epithelial cells and mediated by the estrogen receptor variant ERα36. Since cellular phenotypes are similar in vivo and in vitro and involve the unique ERα36 human variant , such consequences of alkylphenol exposure could be extrapolated from mouse model to human. Low dose alkylphenol transgenerational exposure could promote abnormal mammary gland development and subsequently increase the risk of breast cancer at ageing

Simulation of the discharge propagation in a capillary tube in air at atmospheric pressure

International audienceThis paper presents simulations of an air plasma discharge at atmospheric pressure initiated by a needle anode set inside a dielectric capillary tube. We have studied the influence of the tube inner radius and its relative permittivity ε r on the discharge structure and dynamics. As a reference, we have used a relative permittivity ε r = 1 to study only the influence of the cylindrical constraint of the tube on the discharge. For a tube radius of 100 µm and ε r = 1, we have shown that the discharge fills the tube during its propagation and is rather homogeneous behind the discharge front. When the radius of the tube is in the range 300 to 600 µm, the discharge structure is tubular with peak values of electric field and electron density close to the dielectric surface. When the radius of the tube is larger than 700 µm, the tube has no influence on the discharge which propagates axially. For a tube radius of 100 µm, when ε r increases from 1 to 10, the discharge structure becomes tubular. We have noted that the velocity of propagation of the discharge in the tube increases when the front is more homogeneous and then, the discharge velocity increases with the decrease of the tube radius and ε r. Then, we have compared the relative influence of the value of tube radius and ε r on the discharge characteristics. Our simulations indicate that the geometrical constraint of the cylindrical tube has more influence than the value of ε r on the discharge structure and dynamics. Finally, we have studied the influence of photoemission processes on the discharge structure by varying the photoemission coefficient. As expected, we have shown that photoemission, as it increases the number of secondary electrons close to the dielectric surface, promotes the tubular structure of the discharge