{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T02:13:53Z","timestamp":1760148833197,"version":"build-2065373602"},"reference-count":20,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2023,6,2]],"date-time":"2023-06-02T00:00:00Z","timestamp":1685664000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministerio de Econom\u00eda, Industria y Competitividad","award":["PGC2018-095936-B-I00","CUD2021-03","CUD2020-11","CUD2019-10","UZCUD2019-TEC-01","T39-20R","T20-20R","LMP94_21","LMP141_21"],"award-info":[{"award-number":["PGC2018-095936-B-I00","CUD2021-03","CUD2020-11","CUD2019-10","UZCUD2019-TEC-01","T39-20R","T20-20R","LMP94_21","LMP141_21"]}]},{"DOI":"10.13039\/501100003329","name":"FEDER","doi-asserted-by":"publisher","award":["PGC2018-095936-B-I00","CUD2021-03","CUD2020-11","CUD2019-10","UZCUD2019-TEC-01","T39-20R","T20-20R","LMP94_21","LMP141_21"],"award-info":[{"award-number":["PGC2018-095936-B-I00","CUD2021-03","CUD2020-11","CUD2019-10","UZCUD2019-TEC-01","T39-20R","T20-20R","LMP94_21","LMP141_21"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Centro Universitario de la Defensa de Zaragoza (Spain)","award":["PGC2018-095936-B-I00","CUD2021-03","CUD2020-11","CUD2019-10","UZCUD2019-TEC-01","T39-20R","T20-20R","LMP94_21","LMP141_21"],"award-info":[{"award-number":["PGC2018-095936-B-I00","CUD2021-03","CUD2020-11","CUD2019-10","UZCUD2019-TEC-01","T39-20R","T20-20R","LMP94_21","LMP141_21"]}]},{"DOI":"10.13039\/501100010067","name":"Arag\u00f3n Government","doi-asserted-by":"publisher","award":["PGC2018-095936-B-I00","CUD2021-03","CUD2020-11","CUD2019-10","UZCUD2019-TEC-01","T39-20R","T20-20R","LMP94_21","LMP141_21"],"award-info":[{"award-number":["PGC2018-095936-B-I00","CUD2021-03","CUD2020-11","CUD2019-10","UZCUD2019-TEC-01","T39-20R","T20-20R","LMP94_21","LMP141_21"]}],"id":[{"id":"10.13039\/501100010067","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Diving can have significant cardiovascular effects on the human body and increase the risk of developing cardiac health issues. This study aimed to investigate the autonomic nervous system (ANS) responses of healthy individuals during simulated dives in hyperbaric chambers and explore the effects of the humid environment on these responses. Electrocardiographic- and heart-rate-variability (HRV)-derived indices were analyzed, and their statistical ranges were compared at different depths during simulated immersions under dry and humid conditions. The results showed that humidity significantly affected the ANS responses of the subjects, leading to reduced parasympathetic activity and increased sympathetic dominance. The power of the high-frequency band of the HRV after removing the influence of respiration, PHF\u22a5\u00af, and the number of pairs of successive normal-to-normal intervals that differ by more than 50 ms divided by the total number of normal-to-normal intervals, pNN50\u00af, indices were found to be the most informative in distinguishing the ANS responses of subjects between the two datasets. Additionally, the statistical ranges of the HRV indices were calculated, and the classification of subjects as \u201cnormal\u201d or \u201cabnormal\u201d was determined based on these ranges. The results showed that the ranges were effective at identifying abnormal ANS responses, indicating the potential use of these ranges as a reference for monitoring the activity of divers and avoiding future immersions if many indices are out of the normal ranges. The bagging method was also used to include some variability in the datasets\u2019 ranges, and the classification results showed that the ranges computed without proper bagging represent reality and its associated variability. Overall, this study provides valuable insights into the ANS responses of healthy individuals during simulated dives in hyperbaric chambers and the effects of humidity on these responses.<\/jats:p>","DOI":"10.3390\/s23115289","type":"journal-article","created":{"date-parts":[[2023,6,2]],"date-time":"2023-06-02T03:25:54Z","timestamp":1685676354000},"page":"5289","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Enhancing Safety in Hyperbaric Environments through Analysis of Autonomic Nervous System Responses: A Comparison of Dry and Humid Conditions"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4273-5403","authenticated-orcid":false,"given":"Carlos","family":"S\u00e1nchez","sequence":"first","affiliation":[{"name":"BSICoS Group, I3A Institute, IIS Arag\u00f3n, University of Zaragoza, 50018 Zaragoza, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2596-7237","authenticated-orcid":false,"given":"Alberto","family":"Hernando","sequence":"additional","affiliation":[{"name":"BSICoS Group, I3A Institute, IIS Arag\u00f3n, University of Zaragoza, 50018 Zaragoza, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4068-127X","authenticated-orcid":false,"given":"Juan","family":"Bolea","sequence":"additional","affiliation":[{"name":"Departamento de F\u00edsica, Centro Universitario de la Defensa de Zaragoza, Academia General Militar, 50090 Zaragoza, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4746-3139","authenticated-orcid":false,"given":"David","family":"Izquierdo","sequence":"additional","affiliation":[{"name":"GTF Group, I3A Institute, University of Zaragoza, 50018 Zaragoza, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3121-1532","authenticated-orcid":false,"given":"Germ\u00e1n","family":"Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"Departamento de Ingenier\u00eda y T\u00e9cnicas Aplicadas, Centro Universitario de la Defensa de San Javier, Academia General del Aire, 30729 Murcia, Spain"}]},{"given":"Agust\u00edn","family":"Olea","sequence":"additional","affiliation":[{"name":"Centro de Buceo de la Armada de Cartagena, 30205 Murcia, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0630-4366","authenticated-orcid":false,"given":"Mar\u00eda Teresa","family":"Lozano","sequence":"additional","affiliation":[{"name":"BSICoS Group, I3A Institute, IIS Arag\u00f3n, University of Zaragoza, 50018 Zaragoza, Spain"},{"name":"Departamento de F\u00edsica, Centro Universitario de la Defensa de Zaragoza, Academia General Militar, 50090 Zaragoza, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0690-3193","authenticated-orcid":false,"given":"Mar\u00eda Dolores","family":"Pel\u00e1ez-Coca","sequence":"additional","affiliation":[{"name":"BSICoS Group, I3A Institute, IIS Arag\u00f3n, University of Zaragoza, 50018 Zaragoza, Spain"},{"name":"Departamento de F\u00edsica, Centro Universitario de la Defensa de Zaragoza, Academia General Militar, 50090 Zaragoza, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"371","DOI":"10.1093\/occmed\/kqx049","article-title":"Diving and long-term cardiovascular health","volume":"67","author":"Irgens","year":"2017","journal-title":"Occup. 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