A study of multiscale density fluctuation measurements

Intriguing parallels between density fluctuation power versus wavenumber on small (mm) and large (Mpc) scales are presented. The comparative study is carried out between fusion plasma measurements and cosmological data. Based on predictions from classical fluid turbulence theory, we argue that our observations are consistent with 2D turbulence. The similar dependencies of density fluctuations on these disparate scales might indicate that primordial turbulence has been expanded to cosmological proportions.Comment: Four pages, three figures. Accepted for publication in IEEE Transactions on Plasma Scienc

Chronic catherization of a hepatic vein, the portal vein and a mesenteric vein in cattle using totally implantable catheter system

Surgical techniques for implanting chronic catheters in a hepatic vein, the portal vein and a mesenterie vein in adult cattle are described. A totally implantable access system pemiitting repeated access to the vascular system is used and evaluated. The average function time for withdrawal of blood of this system for hepatic, portal and mesenteric catheters were 37+10, 31 +19. and 3 +2 weeks (mean + SD). respectively. 111- fusions were possible for much longer time. Advantages of this method were first of all a better quality of life for the experimental animal involved, since no restrain or confinement was needed during housing and handling. The experimental animals could safely graze pastures while equipped with catheters in portal, hepatic and mesenterie veins. Catheter infections were not observed, the maintenance protocol was faster and safer than for conventional catheters. Tissue reactions were limited to a thin layer of fibrous tissue. A disadvantage of this technique was a relatively high cost of the catheter system, when compared to traditional systems

Multi-dimensional parameter estimation of heavy-tailed moving averages

In this paper we present a parametric estimation method for certain multi-parameter heavy-tailed L\'evy-driven moving averages. The theory relies on recent multivariate central limit theorems obtained in [3] via Malliavin calculus on Poisson spaces. Our minimal contrast approach is related to the papers [14, 15], which propose to use the marginal empirical characteristic function to estimate the one-dimensional parameter of the kernel function and the stability index of the driving L\'evy motion. We extend their work to allow for a multi-parametric framework that in particular includes the important examples of the linear fractional stable motion, the stable Ornstein-Uhlenbeck process, certain CARMA(2, 1) models and Ornstein-Uhlenbeck processes with a periodic component among other models. We present both the consistency and the associated central limit theorem of the minimal contrast estimator. Furthermore, we demonstrate numerical analysis to uncover the finite sample performance of our method

Etude Hydrogéochimique des Eaux Souterraines dans la Formation Gréseuse de la Région de Berberati en République Centrafricaine

La population de la République Centrafricaine est inégalement repartie: les zones ouest et sud montrent une densité de population beaucoup plus haute que la partie Est. Pour parvenir à une meilleure connaissance des ressources en eau en présence, la compréhension des conditions de recharge des formations gréseuses et leur interrelation avec les cours d'eau environnants et leur reservoirs constituent les principales lacunes à combler par ce projet. L’étude porte donc sur l’évaluation des ressources en eaux dans la formation gréseuse de Berberati par l’utilisation des techniques hydrogéochimiques de et l’hydrologie isotopiques.The population of the Central African Republic is unevenly distributed: the western and southern zones show a much higher population density than the eastern part. To gain a better understanding of the water resources present, understanding the recharge conditions of grès formations and their interrelation with the surrounding watercourses and reservoirs are the main gaps to be filled by this project. The study therefore focuses on the evaluation of water resources in the Berberati grès formation through the use of hydrogeochemical techniques and isotopic hydrology