Introduction: Approximate entropy (ApEn) is a widely imposed metric to evaluate chaotic response and irregularities of RR-intervals from an electrocardiogram. Yet, the technique problematic due accurate choice tolerance (r) embedding dimension (M). We prescribed these responses in subjects exhibiting symptoms chronic obstructive pulmonary disease (COPD) we strived overcome this disadvantage by ...

Recently, during critical illness, cortisol metabolism was found to be reduced. We hypothesize that such reduced cortisol breakdown may suppress pulsatile ACTH and cortisol secretion via feedback inhibition. To test this hypothesis, nocturnal ACTH and cortisol secretory profiles were constructed by deconvolution analysis from plasma concentration time series in 40 matched critically ill patient...

Several types of entropy estimators exist in the information theory literature. Most of these estimators explicitly involve estimating the density of the available data samples before computing the entropy. However, the entropyestimator using sample spacing avoids this intermediate step and computes the entropy directly using the order-statistics. In this paper, we extend our horizon beyond Sha...

We compute statistical properties of the stochastic entropy production associated with the nonstationary transport of heat through a system coupled to a time dependent nonisothermal heat bath. We study the one-dimensional stochastic evolution of a bound particle in such an environment by solving the appropriate Langevin equation numerically, and by using an approximate analytic solution to the ...

Rationale: The development of closed-loop devices suitable for use in the treatment of epileptic patients would very likely rely on the adequate development of paradigms able to forecast the occurrence of seizures. In this paper, we studied the usefulness of approximate enthropy, of a non-linear paradigm, in this patient population. Methods: We applied approximate entropy (ApEn) analysis to stu...

Abnormal heart rate characteristics of reduced variability and transient decelerations are present early in the course of neonatal sepsis. To investigate the dynamics, we calculated sample entropy, a similar but less biased measure than the popular approximate entropy. Both calculate the probability that epochs of window length m that are similar within a tolerance r remain similar at the next ...

Entropy and information are common measures of probabilistic models of data, frequently used for discrete and discretized but more rarely for continuous data. We employ finite mixture models, which handle continuous and discrete data simultaneously, to construct a probabilistic model whose entropy can be estimated. Analytic estimates of entropy are intractable for some models, so an approximate...

In a curved surface design, the overall shape features that emerge from combinations of shape elements are important. However, controlling the features of the overall shape in curved profiles is difficult using conventional microscopic shape information such as dimension. Herein two types of macroscopic shape information, curvature entropy and quadrature curvature entropy, quantitatively repres...