{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,4]],"date-time":"2025-12-04T09:56:15Z","timestamp":1764842175251,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2019,2,15]],"date-time":"2019-02-15T00:00:00Z","timestamp":1550188800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100002809","name":"Generalitat de Catalunya","doi-asserted-by":"publisher","award":["CERCA Programme"],"award-info":[{"award-number":["CERCA Programme"]}],"id":[{"id":"10.13039\/501100002809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010198","name":"Ministerio de Econom\u00eda, Industria y Competitividad, Gobierno de Espa\u00f1a","doi-asserted-by":"publisher","award":["DPI2015-68820-R MINECO\/FEDER"],"award-info":[{"award-number":["DPI2015-68820-R MINECO\/FEDER"]}],"id":[{"id":"10.13039\/501100010198","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100008593","name":"European Respiratory Society","doi-asserted-by":"publisher","award":["ERS LTRF 2015-5185","ERS LTRF 2017 01-00086"],"award-info":[{"award-number":["ERS LTRF 2015-5185","ERS LTRF 2017 01-00086"]}],"id":[{"id":"10.13039\/100008593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007061","name":"Secretar\u00eda Nacional de Ciencia, Tecnolog\u00eda e Innovaci\u00f3n","doi-asserted-by":"publisher","award":["270-2012-273"],"award-info":[{"award-number":["270-2012-273"]}],"id":[{"id":"10.13039\/501100007061","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Fixed sample entropy (fSampEn) has been successfully applied to myographic signals for inspiratory muscle activity estimation, attenuating interference from cardiac activity. However, several values have been suggested for fSampEn parameters depending on the application, and there is no consensus standard for optimum values. This study aimed to perform a thorough evaluation of the performance of the most relevant fSampEn parameters in myographic respiratory signals, and to propose, for the first time, a set of optimal general fSampEn parameters for a proper estimation of inspiratory muscle activity. Different combinations of fSampEn parameters were used to calculate fSampEn in both non-invasive and the gold standard invasive myographic respiratory signals. All signals were recorded in a heterogeneous population of healthy subjects and chronic obstructive pulmonary disease patients during loaded breathing, thus allowing the performance of fSampEn to be evaluated for a variety of inspiratory muscle activation levels. The performance of fSampEn was assessed by means of the cross-covariance of fSampEn time-series and both mouth and transdiaphragmatic pressures generated by inspiratory muscles. A set of optimal general fSampEn parameters was proposed, allowing fSampEn of different subjects to be compared and contributing to improving the assessment of inspiratory muscle activity in health and disease.<\/jats:p>","DOI":"10.3390\/e21020183","type":"journal-article","created":{"date-parts":[[2019,2,25]],"date-time":"2019-02-25T03:30:08Z","timestamp":1551065408000},"page":"183","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Performance Evaluation of Fixed Sample Entropy in Myographic Signals for Inspiratory Muscle Activity Estimation"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4146-9839","authenticated-orcid":false,"given":"Manuel","family":"Lozano-Garc\u00eda","sequence":"first","affiliation":[{"name":"Biomedical Signal Processing and Interpretation group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), UPC Campus Diagonal-Bes\u00f2s, Av. d\u2019Eduard Maristany 10\u201314, 08930 Barcelona, Spain"},{"name":"Biomedical Research Networking Centre in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 08028 Barcelona, Spain"},{"name":"Department of Automatic Control (ESAII), Universitat Polit\u00e8cnica de Catalunya (UPC)-Barcelona Tech, 08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4126-4462","authenticated-orcid":false,"given":"Luis","family":"Estrada","sequence":"additional","affiliation":[{"name":"Biomedical Signal Processing and Interpretation group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), UPC Campus Diagonal-Bes\u00f2s, Av. d\u2019Eduard Maristany 10\u201314, 08930 Barcelona, Spain"},{"name":"Biomedical Research Networking Centre in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6541-8729","authenticated-orcid":false,"given":"Raimon","family":"Jan\u00e9","sequence":"additional","affiliation":[{"name":"Biomedical Signal Processing and Interpretation group, Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology (BIST), UPC Campus Diagonal-Bes\u00f2s, Av. d\u2019Eduard Maristany 10\u201314, 08930 Barcelona, Spain"},{"name":"Biomedical Research Networking Centre in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), 08028 Barcelona, Spain"},{"name":"Department of Automatic Control (ESAII), Universitat Polit\u00e8cnica de Catalunya (UPC)-Barcelona Tech, 08028 Barcelona, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1183\/09031936.00093408","article-title":"Neural respiratory drive in healthy subjects and in COPD","volume":"33","author":"Jolley","year":"2009","journal-title":"Eur. 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