title: Promoting convergence: the Phi spiral in abduction of mouse corneal behaviors.
abstract: Why do mouse corneal epithelial cells display spiraling patterns? We want to provide an explanation for this phenomenon by applying an idealized problem solving process. Specifically, we applied complementary line-fitting methods to measure transgenic epithelial reporter expression arrangements displayed on three mature, live enucleated globes to clarify the problem. Two prominent logarithmic curves were discovered, one of which displayed the ϕ ratio, an indicator of the optimal configuration in phyllotactic systems. We then utilized two different computational approaches to expose our current understanding of the behavior. In one procedure, which involved an isotropic mechanics-based finite element method, we successfully produced logarithmic spiral curves of maximum shear strain based pathlines but computed dimensions displayed pitch angles of 35° (ϕ spiral is ~17°), which was altered when we fitted the model with published measurements of coarse collagen orientations. We then used model-based reasoning in context of Peircean abduction to select a working hypothesis. Our work serves as a concise example of applying a scientific habit of mind and illustrates nuances of executing a common method to doing integrative science.
authors.affiliation: Lurie Children's Research Center, Developmental Biology Program and Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL.
authors.forename: Jerry
authors.initials: J
authors.lastname: Rhee
authors.affiliation: Department of Civil and Materials Engineering, University of Illinois at Chicago, Chicago, IL.
authors.forename: Talisa Mohammad
authors.initials: TM
authors.lastname: Nejad
authors.affiliation: Department of Materials Science and Engineering, Northwestern University, Chicago, IL.
authors.forename: Olivier
authors.initials: O
authors.lastname: Comets
authors.affiliation: Lurie Children's Research Center, Developmental Biology Program and Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL.
authors.forename: Sean
authors.initials: S
authors.lastname: Flannery
authors.affiliation: Department of Materials Science and Engineering, Northwestern University, Chicago, IL.
authors.forename: Emine Begum
authors.initials: EB
authors.lastname: Gulsoy
authors.affiliation: Lurie Children's Research Center, Developmental Biology Program and Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, IL.
authors.forename: Philip
authors.initials: P
authors.lastname: Iannaccone
authors.affiliation: Department of Civil and Materials Engineering, University of Illinois at Chicago, Chicago, IL.
authors.forename: Craig
authors.initials: C
authors.lastname: Foster