Reply to "Comment on `Performance of different synchronization measures in real data: A case study on electroencephalographic signals'"

We agree with the Comment by Nicolaou and Nasuto about the utility of mutual information (MI) when properly estimated and we also concur with their view that the estimation based on k nearest neighbors gives optimal results. However, we claim that embedding parameters can indeed change MI results, as we show for the electroencephalogram data sets of our original study and for coupled chaotic systems. Furthermore, we show that proper embedding can actually improve the estimation of MI with the k nearest neighbors algorithm

Fluvic acid carbon as a dignostic feature for agricultural soil evaluation

The fluvic acid fraction in considered to be sensitive to agronomic and environment factors. Therefore, the objectives of this study were to evaluate total carbon (TC) and fluvic acid carbon (FC) contens and to establish a possible relationship between the FC fraction and coarse organic matter in agricultural soils (CTVs), (ii) conservation tilled soils (CSTs), and (iii) virgins soils (VIRs) from a wide region in Argentina. The investigation includes 114 surface samples of Hapludolls, Haplustolls, and Entisols ranging in texture from sand to slit loam. In 29 selected samples, two separate soil mineral fraction were used (<0.05 mm and 0.1-2 mm) to determinate FC and TC contents. No statistically significant differences were found in TC contents in the fine fraction < 0.05 mm between VlRs, CSTs, and CVTs; however, FC contents were higher in VIRs than in CSTs and CVTs at the 0.05 probability level. In addition" statistically significant differences (P< 0.05) observed in FC contents among all three treatments in the coarse fraction 0.1-2 mm confirm that the FC fraction Is more influenced by the farming-system thn Is TC. Moreover, FC I TC ratios tended to increase under agricultural land use (CVTs > CSTs > VIRs), and this radio also Increased from finer textured soils to creaser tent was highly related to recently incorporated organic residues.Resúmenes de Trabajos presentados en otras publicaciones (por docentes de la UNLPam.) Publicado en Soil Science 1999; Vol 164: 57-6

Vanishing Cosmological Constant in Modified Gauss-Bonnet Gravity with Conformal Anomaly

We consider dark energy cosmology in a de Sitter universe filled with quantum conformal matter. Our model represents a Gauss-Bonnet model of gravity with contributions from quantum effects. To the General Relativity action an arbitrary function of the GB invariant, f(G), is added, and taking into account quantum effects from matter the cosmological constant is studied. For the considered model the conditions for a vanishing cosmological constant are considered. Creation of a de Sitter universe by quantum effects in a GB modified gravity is discussed.Comment: 8 pages latex, 1 figure. To appear in Int. J. Mod. Phys.

Two and three electrons in a quantum dot: 1/|J| - expansion

We consider systems of two and three electrons in a two-dimensional parabolic quantum dot. A magnetic field is applied perpendicularly to the electron plane of motion. We show that the energy levels corresponding to states with high angular momentum, J, and a low number of vibrational quanta may be systematically computed as power series in 1/|J|. These states are relevant in the high-B limit.Comment: LaTeX, 15 pages,6 postscript figure

Kullback-Leibler and Renormalized Entropy: Applications to EEGs of Epilepsy Patients

Recently, renormalized entropy was proposed as a novel measure of relative entropy (P. Saparin et al., Chaos, Solitons & Fractals 4, 1907 (1994)) and applied to several physiological time sequences, including EEGs of patients with epilepsy. We show here that this measure is just a modified Kullback-Leibler (K-L) relative entropy, and it gives similar numerical results to the standard K-L entropy. The latter better distinguishes frequency contents of e.g. seizure and background EEGs than renormalized entropy. We thus propose that renormalized entropy might not be as useful as claimed by its proponents. In passing we also make some critical remarks about the implementation of these methods.Comment: 15 pages, 4 Postscript figures. Submitted to Phys. Rev. E, 199

Commutative C∗C^*-algebras of Toeplitz operators on complex projective spaces

We prove the existence of commutative $C^*$-algebras of Toeplitz operators on every weighted Bergman space over the complex projective space $\mathbb{P}^n(\mathbb{C})$. The symbols that define our algebras are those that depend only on the radial part of the homogeneous coordinates. The algebras presented have an associated pair of Lagrangian foliations with distinguished geometric properties and are closely related to the geometry of $\mathbb{P}^n(\mathbb{C})$