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In this in-vitro study, we investigate whether pulsed-wave (PW) Doppler ultrasound can capture structured spectral patterns from replayed lung sound recordings.<\/jats:p>\n                <jats:p>Digitized respiratory sounds were replayed through a tissue-mimicking ultrasound phantom, generating 1,478 PW Doppler spectral images from recordings associated with healthy subjects and several externally labeled disease categories. Exploratory classification experiments using a ResNet-18 architecture demonstrated that these Doppler representations contain learnable differences under controlled conditions.<\/jats:p>\n                <jats:p>These findings motivate further investigation into PW Doppler as a potential representation of respiratory acoustics.<\/jats:p>","DOI":"10.64898\/2026.06.09.26353787","type":"posted-content","created":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T05:00:19Z","timestamp":1781154019000},"source":"Crossref","is-referenced-by-count":0,"title":["Exploratory Assessment of Pulsed-Wave Doppler Representations of Lung Sounds Using Deep Learning: An In-Vitro Phantom Study"],"prefix":"10.64898","author":[{"given":"Ali A.","family":"Saad","sequence":"first","affiliation":[{"name":"alumnus of Johns Hopkins University, Baltimore, MD, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah B.","family":"Murthi","sequence":"additional","affiliation":[{"name":"University of Maryland School of Medicine, R Adams Cowley Shock Trauma Center, Baltimore, MD, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emad M.","family":"Boctor","sequence":"additional","affiliation":[{"name":"Laboratory for Computational Sensing and Robotics, Johns Hopkins University, Whiting School of Engineering, Baltimore, Maryland, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"William A.","family":"Teeter","sequence":"additional","affiliation":[{"name":"University of Maryland School of Medicine, R Adams Cowley Shock Trauma Center, Baltimore, MD, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nitin","family":"Seam","sequence":"additional","affiliation":[{"name":"Critical Care Medicine Department, National Institutes of Health Clinical Center, Bethesda, MD, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"54368","reference":[{"key":"2026061311151056000_2026.06.09.26353787v1.1","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMra1302901"},{"key":"2026061311151056000_2026.06.09.26353787v1.2","doi-asserted-by":"publisher","DOI":"10.1183\/13993003.01132-2015"},{"key":"2026061311151056000_2026.06.09.26353787v1.3","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-020-64405-6"},{"key":"2026061311151056000_2026.06.09.26353787v1.4","doi-asserted-by":"publisher","DOI":"10.1136\/bmjresp-2017-000250"},{"key":"2026061311151056000_2026.06.09.26353787v1.5","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0220606"},{"key":"2026061311151056000_2026.06.09.26353787v1.6","doi-asserted-by":"publisher","DOI":"10.1038\/s41533-024-00392-9"},{"key":"2026061311151056000_2026.06.09.26353787v1.7","doi-asserted-by":"publisher","DOI":"10.1080\/17476348.2025.2511223"},{"key":"2026061311151056000_2026.06.09.26353787v1.8","doi-asserted-by":"publisher","DOI":"10.3390\/diagnostics13091545"},{"key":"2026061311151056000_2026.06.09.26353787v1.9","doi-asserted-by":"publisher","DOI":"10.1186\/s12931-020-01523-9"},{"key":"2026061311151056000_2026.06.09.26353787v1.10","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0177926"},{"key":"2026061311151056000_2026.06.09.26353787v1.11","doi-asserted-by":"publisher","DOI":"10.4103\/0970-2113.156245"},{"key":"2026061311151056000_2026.06.09.26353787v1.12","doi-asserted-by":"publisher","DOI":"10.1148\/ryct.2021200564"},{"key":"2026061311151056000_2026.06.09.26353787v1.13","doi-asserted-by":"publisher","DOI":"10.1186\/1465-9921-15-50"},{"key":"2026061311151056000_2026.06.09.26353787v1.14","doi-asserted-by":"publisher","DOI":"10.1002\/jum.16088"},{"key":"2026061311151056000_2026.06.09.26353787v1.15","doi-asserted-by":"publisher","DOI":"10.3390\/arm91030017"},{"key":"2026061311151056000_2026.06.09.26353787v1.16","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMvcm2108203"},{"key":"2026061311151056000_2026.06.09.26353787v1.17","doi-asserted-by":"publisher","DOI":"10.29390\/001c.92182"},{"key":"2026061311151056000_2026.06.09.26353787v1.18","doi-asserted-by":"publisher","DOI":"10.1007\/s00134-019-05725-8"},{"key":"2026061311151056000_2026.06.09.26353787v1.19","doi-asserted-by":"publisher","DOI":"10.1016\/j.afjem.2020.04.007"},{"key":"2026061311151056000_2026.06.09.26353787v1.20","doi-asserted-by":"publisher","DOI":"10.1186\/s13054-019-2719-8"},{"key":"2026061311151056000_2026.06.09.26353787v1.21","doi-asserted-by":"publisher","DOI":"10.1088\/1361-6579\/ab03ea"},{"key":"2026061311151056000_2026.06.09.26353787v1.22","unstructured":"HEYSONG. 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