Volume 6 Issue 2 Structural anisotropy in celery stalks by microscopic MRI and polarized light microscopy
Published 28 May, 2026
A pair of calculated images from quantitative polarized light microscopy at 1µm/pixel, retardation (left) and angle (right). The retardation image has a gray scale in nm; the angle image exhibits a fibril rotation shown by the repeating the 0-180˚ color scale. The images contain a complete bundle of vascular tubes (p for parenchyma, c for collenchyma, ph for phloem, and x for xylem). The differences in the vessel sizes and structures give arise to different anisotropies in the spin-spin relaxation by µMRI.
Yang Xia
Yang Xia completed his MSc (1989) and PhD (1992) dissertation research under the guidance of Paul T Callaghan at Massey University (New Zealand). After a two-year postdoctoral research at Cornell University (Ithaca, New York), he joined the Physics Faculty at Oakland University and now holds the rank of Distinguished Professor. His major research effort at Oakland has been the study of osteoarthritic degradation in articular cartilage using multidisciplinary microscopic imaging techniques (microscopic MRI, polarized light microscopy, Fourier-transform infrared microscopy, microscopic computer tomography, biomechanical imaging). He is the lead editor for a 2016 book titled "Biophysics and Biochemistry of Cartilage by NMR and MRI". In 2022, he published a textbook titled "Essential Concepts in MRI: Physics, Instrumentation, Spectroscopy and Imaging".
