{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T10:41:32Z","timestamp":1778582492035,"version":"3.51.4"},"reference-count":47,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2018,11,9]],"date-time":"2018-11-09T00:00:00Z","timestamp":1541721600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Information theory provides a spectrum of nonlinear methods capable of grasping an internal structure of a signal together with an insight into its complex nature. In this work, we discuss the usefulness of the selected entropy techniques for a description of the information carried by the surface electromyography signals during colorectal cancer treatment. The electrical activity of the external anal sphincter can serve as a potential source of knowledge of the actual state of the patient who underwent a common surgery for rectal cancer in the form of anterior or lower anterior resection. The calculation of Sample entropy parameters has been extended to multiple time scales in terms of the Multiscale Sample Entropy. The specific values of the entropy measures and their dependence on the time scales were analyzed with regard to the time elapsed since the operation, the type of surgical treatment and also the different depths of the rectum canal. The Mann\u2013Whitney U test and Anova Friedman statistics indicate the statistically significant differences among all of stages of treatment and for all consecutive depths of rectum area for the estimated Sample Entropy. The further analysis at the multiple time scales signify the substantial differences among compared stages of treatment in the group of patients who underwent the lower anterior resection.<\/jats:p>","DOI":"10.3390\/e20110863","type":"journal-article","created":{"date-parts":[[2018,11,13]],"date-time":"2018-11-13T03:27:31Z","timestamp":1542079651000},"page":"863","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Sample Entropy of sEMG Signals at Different Stages of Rectal Cancer Treatment"],"prefix":"10.3390","volume":"20","author":[{"given":"Paulina","family":"Trybek","sequence":"first","affiliation":[{"name":"Division of Computational Physics and Electronics, Institute of Physics, Silesian Centre for Education and Interdisciplinary Research, University of Silesia in Katowice, 40007 Katowice, Poland"}]},{"given":"Michal","family":"Nowakowski","sequence":"additional","affiliation":[{"name":"Department of General Surgery and Multiorgan Trauma, Jagiellonian University Medical College, 30048 Krakow, Poland"}]},{"given":"Jerzy","family":"Salowka","sequence":"additional","affiliation":[{"name":"Department of Surgery, Stanley Dudrick Memorial Hospital, 32050 Skawina, Poland"}]},{"given":"Jakub","family":"Spiechowicz","sequence":"additional","affiliation":[{"name":"Department of Theoretical Physics, Institute of Physics, Silesian Centre for Education and Interdisciplinary Research, University of Silesia in Katowice, 40007 Katowice, Poland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2781-3426","authenticated-orcid":false,"given":"Lukasz","family":"Machura","sequence":"additional","affiliation":[{"name":"Division of Computational Physics and Electronics, Institute of Physics, Silesian Centre for Education and Interdisciplinary Research, University of Silesia in Katowice, 40007 Katowice, Poland"}]}],"member":"1968","published-online":{"date-parts":[[2018,11,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"790","DOI":"10.1016\/S1470-2045(12)70211-5","article-title":"Global cancer transitions according to the Human Development Index (2008\u20132030): A population-based study","volume":"13","author":"Bray","year":"2012","journal-title":"Lancet Oncol."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Ferlay, J., Soerjomataram, I., Dikshit, R., Eser, S., Mathers, C., Rebelo, M., Parkin, D.M., Forman, D., and Bray, F. 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