Dysphagia lusoria: uncommon cause of dysphagia in children

Dysphagia lusoria (lusus naturae, latin for "freak of nature") describes dysphagia because of vascular compression of the esophagus. Symptoms, when present, occur at the two extremes of life. Owing to the more flexible and compressible nature of the trachea, children usually present with respiratory symptoms, in contrast to adults, who more often present with dysphagia. Here, we report the case of a six-year-old child presenting with a history of progressive dysphagia without respiratory symptoms. A barium esophagogram showed a diagonal impression in the proximal esophagus, while at esophagogastroduodenoscopy there was an extrinsic pulsatile bulging area suggesting an extrinsic compression by an aberrant vessel. Angio-CT (computed tomography) scan confirmed the presence of an aberrant right subclavian artery.info:eu-repo/semantics/publishedVersio

Symbolic Sequences and Tsallis Entropy

We address this work to investigate symbolic sequences with long-range correlations by using computational simulation. We analyze sequences with two, three and four symbols that could be repeated $l$ times, with the probability distribution $p(l)\propto 1/ l^{\mu}$. For these sequences, we verified that the usual entropy increases more slowly when the symbols are correlated and the Tsallis entropy exhibits, for a suitable choice of $q$, a linear behavior. We also study the chain as a random walk-like process and observe a nonusual diffusive behavior depending on the values of the parameter $\mu$.Comment: Published in the Brazilian Journal of Physic

New Algorithms for Computing a Single Component of the Discrete Fourier Transform

This paper introduces the theory and hardware implementation of two new algorithms for computing a single component of the discrete Fourier transform. In terms of multiplicative complexity, both algorithms are more efficient, in general, than the well known Goertzel Algorithm.Comment: 4 pages, 3 figures, 1 table. In: 10th International Symposium on Communication Theory and Applications, Ambleside, U