Analysis of a New Three-Dimensional Quadratic Chaotic System

This paper has reported the finding of a new simple three dimensional quadratic chaotic system with three nonlinearities obtained by adding a cross-product nonlinear term to the first equation of the Lu system. Basic properties of the system have been analyzed by means of Lyapunov exponent spectrum and bifurcation diagram of an associated Poincare map. This analysis shows that the system has complex dynamics with some interesting characteristics in which there are several periodic regions, but each of them has quite different periodic orbits. Shilnikov’s criterion is included and discussed

Electronic circuit implementation of chaos synchronization

In this paper, an electronic circuit implementation of a robustly chaotic two-dimensional map is presented. Two such electronic circuits are realized. One of the circuits is configured as the driver and the other circuit is configured as the driven system. Synchronization of chaos between the driver and the driven system is demonstrated

Dynamique de la conductance hydraulique chez l'olivier de table (Olea europaea L., cv Meski)

Hydraulic Conductance Dynamic in Olive Table Tree (Olea europaea L. cv Meski). Cette étude expose les effets de l'aménagement des pâturages par la digue filtrante sur la dynamique de la végétation. Dans les régions sahéliennes, de nombreuses techniques sont appliquées sur les sols pour la restauration des parcours dégradés. La digue filtrante s'intéresse particulièrement aux axes de drainage ou bas-fonds en dégradation. La méthode d'étude a consisté à évaluer l'impact des digues filtrantes par l'inventaire de la végétation, la mesure de la biomasse produite, et l'analyse chimique d'échantillons de fourrage et de sol. Ces observations ont été faites à la fois sur l'espace aménagé et sur un espace témoin représentatif en deux fois durant cinq ans. Les observations sur l'espace aménagé (stations d'observation d'un ha) ont été faites en fonction du gradient par rapport à la digue filtrante tandis que sur le témoin (station d'observation d'un ha), les mesures ont été homogénéisées sur l'ensemble de la parcelle. Les résultats obtenus des inventaires de végétation montrent un effet positif de l'aménagement sur la dynamique de la végétation qui se maintient après cinq années. Les effets concernent la composition floristique pour laquelle certaines espèces connaissent une amélioration. Il s'agit de Panicum laetum (+ 5,9% en 1999 et + 1,9% en 2003), Setaria pallide fusca (+ 2,4 à + 8,6%), Cassia obtusifolia (+ 13,6% à + 9,3%) et Zornia glochidiata (- 2,9% à + 1,7 %). Les espèces en régression sont surtout composées de Schoenefeldia gracilis (+ 1,7% à - 12%) et Microchloa indica (- 28,9% à - 12,1% entre 1999 et 2003). L'écart de recouvrement du sol entre la parcelle aménagée et le témoin a été de -0,4% en 1999 contre + 14,6% en 2003. La biomasse produite et la capacité de charge ont connu une expansion allant de 3,14 à 4,5 fois par rapport à l'espace non aménagé. Cependant, des suivis doivent encore être maintenus en associant surtout les effets de l'exploitation (fauche et pâture) pour mieux préciser l'efficacité et la durabilité de ces aménagements sur les zones pastorales en même temps que des stratégies sont définies au niveau village sur la gestion de ces espaces restaurés

Surface Aggregation of Urinary Proteins and Aspartic Acid-Rich Peptides on the Faces of Calcium Oxalate Monohydrate Investigated by In Situ Force Microscopy

The growth of calcium oxalate monohydrate in the presence of Tamm-Horsfall protein (THP), osteopontin, and the 27-residue synthetic peptides (DDDS)6DDD and (DDDG)6DDD (D = aspartic acid, S = serine, and G = glycine) was investigated via in situ atomic force microscopy. The results show that these four growth modulators create extensive deposits on the crystal faces. Depending on the modulator and crystal face, these deposits can occur as discrete aggregates, filamentary structures, or uniform coatings. These proteinaceous films can lead to either the inhibition of or an increase in the step speeds (with respect to the impurity-free system), depending on a range of factors that include peptide or protein concentration, supersaturation, and ionic strength. While THP and the linear peptides act, respectively, to exclusively increase and inhibit growth on the \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\left( {\bar{1}01} \right)$$\end{document} face, both exhibit dual functionality on the (010) face, inhibiting growth at low supersaturation or high modulator concentration and accelerating growth at high supersaturation or low modulator concentration. Based on analyses of growth morphologies and dependencies of step speeds on supersaturation and protein or peptide concentration, we propose a picture of growth modulation that accounts for the observations in terms of the strength of binding to the surfaces and steps and the interplay of electrostatic and solvent-induced forces at the crystal surface

Endothelial Cell Capture of Heparin-Binding Growth Factors under Flow

Circulation is an important delivery method for both natural and synthetic molecules, but microenvironment interactions, regulated by endothelial cells and critical to the molecule's fate, are difficult to interpret using traditional approaches. In this work, we analyzed and predicted growth factor capture under flow using computer modeling and a three-dimensional experimental approach that includes pertinent circulation characteristics such as pulsatile flow, competing binding interactions, and limited bioavailability. An understanding of the controlling features of this process was desired. The experimental module consisted of a bioreactor with synthetic endothelial-lined hollow fibers under flow. The physical design of the system was incorporated into the model parameters. The heparin-binding growth factor fibroblast growth factor-2 (FGF-2) was used for both the experiments and simulations. Our computational model was composed of three parts: (1) media flow equations, (2) mass transport equations and (3) cell surface reaction equations. The model is based on the flow and reactions within a single hollow fiber and was scaled linearly by the total number of fibers for comparison with experimental results. Our model predicted, and experiments confirmed, that removal of heparan sulfate (HS) from the system would result in a dramatic loss of binding by heparin-binding proteins, but not by proteins that do not bind heparin. The model further predicted a significant loss of bound protein at flow rates only slightly higher than average capillary flow rates, corroborated experimentally, suggesting that the probability of capture in a single pass at high flow rates is extremely low. Several other key parameters were investigated with the coupling between receptors and proteoglycans shown to have a critical impact on successful capture. The combined system offers opportunities to examine circulation capture in a straightforward quantitative manner that should prove advantageous for biologicals or drug delivery investigations

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

A New 3-D Piecewise-Linear System for Chaos Generation

We propose in this paper a new simple continuous-time piecewise-linear three dimensional system for chaos generation. Nonlinearity in this model is introduced by the characteristic function of the Chua's circuit given in [1]. Simulated results of some chaotic attractors are shown and justified numerically via computing the largest Lyapunov exponent. The possibility and the robustness of the circuitry realization is also given and discussed

Chaotifying 2-D piecewise linear maps via a piecewise linear controller function

A simple method for chaotifying piecewise linear maps of the plane using a piecewise linear controller function is given. A domain of chaosin the resulting controlled map was determined exactly and rigorously.Наведено простий метод хаотизацiї кусково-лiнiйних вiдображень площини за допомогою кусково-лiнiйної функцiї керування. Множину хаосу для отриманого керованого вiдображення визначено точно i строго