{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T20:39:58Z","timestamp":1791923998447,"version":"4.3.4"},"reference-count":90,"publisher":"American Physiological Society","issue":"2","funder":[{"DOI":"10.13039\/100000001","name":"National Science Foundation (NSF)","doi-asserted-by":"publisher","award":["CBET-1453538"],"award-info":[{"award-number":["CBET-1453538"]}],"id":[{"id":"10.13039\/100000001","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000002","name":"HHS | National Institutes of Health (NIH)","doi-asserted-by":"publisher","award":["NHLBI-R21HL129906"],"award-info":[{"award-number":["NHLBI-R21HL129906"]}],"id":[{"id":"10.13039\/100000002","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000050","name":"HHS | NIH | National Heart, Lung, and Blood Institute (NHBLI)","doi-asserted-by":"publisher","award":["R01 HL089897"],"award-info":[{"award-number":["R01 HL089897"]}],"id":[{"id":"10.13039\/100000050","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000050","name":"HHS | NIH | National Heart, Lung, and Blood Institute (NHBLI)","doi-asserted-by":"publisher","award":["R01 HL089856"],"award-info":[{"award-number":["R01 HL089856"]}],"id":[{"id":"10.13039\/100000050","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Journal of Applied Physiology"],"published-print":{"date-parts":[[2018,2,1]]},"abstract":"<jats:p>The accurate representation of the human airway anatomy is crucial for understanding and modeling the structure-function relationship in both healthy and diseased lungs. The present knowledge in this area is based on morphometric studies of excised lung casts, partially complemented by in vivo studies in which computed tomography (CT) was used on a small number of subjects. In the present study, we analyzed CT scans of a cohort of healthy subjects and obtained comprehensive morphometric information down to the seventh generation of bronchial branching, including airway diameter, length, branching angle, and rotation angle. Although some of the geometric parameters (such as the child-to-parent branch diameter ratio) are found to be in line with accepted values, for others (such as the branch length-to-diameter ratio) our findings challenge the common assumptions. We also evaluated several metrics of self-similarity, including the fractal dimension of the airway tree. Additionally, we used phase-contrast magnetic resonance imaging (MRI) to obtain the volumetric flow field in the three-dimensional-printed airway model of one of the subjects during steady inhalation. This is used to relate structural and functional parameters and, in particular, to close the power-law relationship between branch flow rate and diameter. The diameter exponent is found to be significantly lower than in the usually assumed Poiseuille regime, which we attribute to the strong secondary (i.e., transverse) velocity component. The strength of the secondary velocity with respect to the axial component exceeds the levels found in idealized airway models and persists within the first seven generations.<\/jats:p>\n                  <jats:p>NEW &amp; NOTEWORTHY We performed a comprehensive computed tomography-based study of the conductive airway morphology in normal human subjects, including branch diameter, length, and mutual angles. We found significant departure from classic homothetic relationships. We also carried out MRI measurements of the three-dimensional inspiratory flow in an anatomy-based model and directly assessed structure-function relationships that have so far been assumed. We found that strong secondary flows (i.e., transverse velocity components) persist through the first seven generations of bronchial branching.<\/jats:p>","DOI":"10.1152\/japplphysiol.00490.2017","type":"journal-article","created":{"date-parts":[[2017,11,2]],"date-time":"2017-11-02T15:49:40Z","timestamp":1509637780000},"page":"400-413","source":"Crossref","is-referenced-by-count":21,"title":["Morphological and functional properties of the conducting human airways investigated by in vivo computed tomography and in vitro MRI"],"prefix":"10.1152","volume":"124","author":[{"given":"Tristan","family":"Van de Moortele","sequence":"first","affiliation":[{"name":"Department of Aerospace Engineering and Mechanics, University of Minnesota, Minneapolis, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christine H.","family":"Wendt","sequence":"additional","affiliation":[{"name":"Department of Medicine, Veterans Affairs Medical Center, University of Minnesota, Minneapolis, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Filippo","family":"Coletti","sequence":"additional","affiliation":[{"name":"Department of Aerospace Engineering and Mechanics, University of Minnesota, Minneapolis, Minnesota"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"24","reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1378\/chest.07-2779"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijheatfluidflow.2016.04.006"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1007\/s00348-015-1966-y"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1164\/rccm.200411-1463OC"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1097\/00005382-199424000-00002"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1017\/S0022112001003809"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1016\/j.medengphy.2007.11.002"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1148\/radiol.10100322"},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.01610.2005"},{"key":"B10","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00866.2010"},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.1007\/s00348-007-0383-2"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1007\/s00348-003-0587-z"},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00984.2010"},{"key":"B14","doi-asserted-by":"publisher","DOI":"10.1115\/1.2768374"},{"key":"B15","doi-asserted-by":"publisher","DOI":"10.1002\/cphy.c090002"},{"key":"B16","first-page":"25","volume":"9","author":"Goldberger AL","year":"1992","journal-title":"MD Comput"},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1007\/s00348-007-0318-y"},{"key":"B18","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.fl.26.010194.002525"},{"key":"B19","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.bioeng.3.1.421"},{"key":"B20","doi-asserted-by":"publisher","DOI":"10.1164\/rccm.200601-037OC"},{"key":"B21","doi-asserted-by":"publisher","DOI":"10.1016\/j.acra.2004.09.005"},{"key":"B22","doi-asserted-by":"publisher","DOI":"10.1016\/S1076-6332(03)00330-1"},{"key":"B23","first-page":"23","volume":"25","author":"Horsfield K","year":"1985","journal-title":"Lung Biol Health Dis"},{"key":"B24","doi-asserted-by":"publisher","DOI":"10.1007\/BF02476898"},{"key":"B25","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1968.24.3.373"},{"key":"B26","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1971.31.2.207"},{"key":"B27","doi-asserted-by":"publisher","DOI":"10.1007\/BF02458417"},{"key":"B28","doi-asserted-by":"publisher","DOI":"10.1016\/0034-5687(82)90105-0"},{"key":"B29","doi-asserted-by":"publisher","DOI":"10.1007\/s00348-016-2234-5"},{"key":"B30","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1989.67.1.147"},{"key":"B31","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00856.2006"},{"key":"B32","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.bioeng.1.1.47"},{"key":"B33","doi-asserted-by":"publisher","DOI":"10.1152\/ajpheart.00579.2005"},{"key":"B34","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pcbi.1002474"},{"key":"B35","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1997.82.3.968"},{"key":"B36","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1999.87.6.2207"},{"key":"B37","doi-asserted-by":"publisher","DOI":"10.1146\/annurev-fluid-121108-145453"},{"key":"B38","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.bioeng.10.061807.160544"},{"key":"B39","doi-asserted-by":"publisher","DOI":"10.1016\/j.resp.2008.07.002"},{"key":"B40","doi-asserted-by":"publisher","DOI":"10.1016\/0167-9473(95)92763-N"},{"key":"B41","doi-asserted-by":"publisher","DOI":"10.1080\/02786826.2010.517578"},{"key":"B42","doi-asserted-by":"publisher","DOI":"10.1038\/nrclinonc.2015.108"},{"key":"B43","doi-asserted-by":"publisher","DOI":"10.1016\/j.resp.2007.02.006"},{"key":"B44","doi-asserted-by":"publisher","DOI":"10.1007\/s10439-008-9620-y"},{"key":"B45","doi-asserted-by":"publisher","DOI":"10.1103\/PhysRevLett.95.168101"},{"key":"B46","first-page":"38","volume":"127","author":"Mandelbrot B","year":"1990","journal-title":"New Sci"},{"key":"B47","doi-asserted-by":"publisher","DOI":"10.1119\/1.13295"},{"key":"B48","doi-asserted-by":"publisher","DOI":"10.1002\/jmri.23632"},{"key":"B49","doi-asserted-by":"publisher","DOI":"10.1016\/0010-4825(95)00027-2"},{"key":"B50","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.bioeng.6.040803.140100"},{"key":"B51","doi-asserted-by":"publisher","DOI":"10.1103\/PhysRevLett.90.148101"},{"key":"B52","doi-asserted-by":"publisher","DOI":"10.1038\/nature02287"},{"key":"B53","doi-asserted-by":"publisher","DOI":"10.1016\/j.jaerosci.2016.07.006"},{"key":"B54","doi-asserted-by":"publisher","DOI":"10.1111\/j.1469-7580.2007.00811.x"},{"key":"B55","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.12.3.207"},{"key":"B56","doi-asserted-by":"publisher","DOI":"10.1164\/ajrccm.162.3.9907120"},{"key":"B57","doi-asserted-by":"publisher","DOI":"10.1109\/42.14515"},{"key":"B58","doi-asserted-by":"publisher","DOI":"10.1007\/BF01951755"},{"key":"B59","doi-asserted-by":"publisher","DOI":"10.1114\/1.1560632"},{"key":"B60","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.fl.09.010177.001305"},{"key":"B61","doi-asserted-by":"publisher","DOI":"10.1002\/jmri.1880010404"},{"key":"B62","first-page":"125","volume":"10","author":"Pelc NJ","year":"1994","journal-title":"Magn Reson Q"},{"key":"B63","doi-asserted-by":"publisher","DOI":"10.1002\/ar.1091900202"},{"key":"B64","doi-asserted-by":"publisher","DOI":"10.1016\/0034-5687(95)00056-9"},{"key":"B65","doi-asserted-by":"publisher","DOI":"10.1006\/jtbi.2000.2060"},{"key":"B66","volume-title":"Tracheobronchial Geometry: Human, Dog, Rat, Hamster\u2013A Compilation of Selected Data from the Project Respiratory Tract Deposition Models","author":"Raabe OG","year":"1976"},{"key":"B67","doi-asserted-by":"publisher","DOI":"10.3109\/15412550903499522"},{"key":"B68","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0144282"},{"key":"B69","doi-asserted-by":"publisher","DOI":"10.1046\/j.0021-8782.2001.00018.x"},{"key":"B70","doi-asserted-by":"publisher","DOI":"10.1016\/0034-5687(69)90018-8"},{"key":"B71","doi-asserted-by":"publisher","DOI":"10.1007\/s00348-013-1562-y"},{"key":"B72","volume-title":"Morphological and Morphometrical Analysis of Circulation in Hypertension and Ischemic Kidney","author":"Suwa N","year":"1971"},{"key":"B73","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00520.2004"},{"key":"B74","doi-asserted-by":"publisher","DOI":"10.1002\/cphy.c100020"},{"key":"B75","doi-asserted-by":"publisher","DOI":"10.1016\/0034-5687(80)90050-X"},{"key":"B76","doi-asserted-by":"publisher","DOI":"10.1007\/BF02461198"},{"key":"B77","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00795.2004"},{"key":"B78","doi-asserted-by":"publisher","DOI":"10.1002\/fld.1763"},{"key":"B79","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00004.2013"},{"key":"B80","doi-asserted-by":"publisher","DOI":"10.1152\/ajplung.1991.261.6.L361"},{"key":"B81","first-page":"131","volume":"12","author":"Weibel ER","year":"1963","journal-title":"Lab Invest"},{"key":"B82","first-page":"375","volume":"139","author":"Weibel ER","year":"2009","journal-title":"Swiss Med Wkly"},{"key":"B83","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1986.60.3.1089"},{"key":"B84","doi-asserted-by":"publisher","DOI":"10.1126\/science.276.5309.122"},{"key":"B85","doi-asserted-by":"publisher","DOI":"10.1038\/213668a0"},{"key":"B86","doi-asserted-by":"publisher","DOI":"10.1007\/s10439-010-9956-y"},{"key":"B87","doi-asserted-by":"publisher","DOI":"10.1016\/j.jcp.2012.12.007"},{"key":"B88","doi-asserted-by":"publisher","DOI":"10.1016\/j.jbiomech.2010.03.048"},{"key":"B89","doi-asserted-by":"publisher","DOI":"10.1063\/1.1433495"},{"key":"B90","doi-asserted-by":"publisher","DOI":"10.1016\/j.jaerosci.2011.12.002"}],"container-title":["Journal of Applied Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.physiology.org\/doi\/pdf\/10.1152\/japplphysiol.00490.2017","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,9,22]],"date-time":"2019-09-22T12:45:01Z","timestamp":1569156301000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.physiology.org\/doi\/10.1152\/japplphysiol.00490.2017"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,2,1]]},"references-count":90,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2018,2,1]]}},"alternative-id":["10.1152\/japplphysiol.00490.2017"],"URL":"https:\/\/doi.org\/10.1152\/japplphysiol.00490.2017","relation":{},"ISSN":["8750-7587","1522-1601"],"issn-type":[{"value":"8750-7587","type":"print"},{"value":"1522-1601","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,2,1]]}}}