title: Digital image analysis of shark gills: modeling of oxygen transfer in the domain of time.
abstract: Digital radiographic imaging of blood circulation through leopard shark gills establishes a secondary lamellar transit time of 6.5 s. This duration, combined with estimates of cardiac output and hemoglobin-oxygen affinity, permits novel modeling of gill oxygen transfer in the time domain. The temporal model allows assessment of factors contributing to previously noted discrepancies between physiological and morphometric branchial oxygen conductance estimates. Lamellar transit time for shark blood is 20 times greater than human alveolar transit time, and thus correlates with a slower rate of hemoglobin-oxygen binding and a greater diffusion distance.
authors.affiliation: Department of Medicine, University of California, San Diego 92093.
authors.forename: V
authors.initials: V
authors.lastname: Bhargava
authors.forename: N C
authors.initials: NC
authors.lastname: Lai
authors.forename: J B
authors.initials: JB
authors.lastname: Graham
authors.forename: S C
authors.initials: SC
authors.lastname: Hempleman
authors.forename: R
authors.initials: R
authors.lastname: Shabetai
mesh_terms: D000818:Animals; D005880:Gills / Q000378:metabolism*; D006439:Hemodynamics; D007091:Image Processing, Computer-Assisted; D008954:Models, Biological; D010100:Oxygen / Q000097:blood / Q000493:pharmacokinetics*; D012754:Sharks / Q000097:blood / Q000378:metabolism*; D013997:Time Factors
chemical_list: D010100:Oxygen