Multiple microscopy modalities applied to a sea urchin tooth fragment.

Two synchrotron X-ray microscopy methods, phase-contrast microradiography (the propagation method) and absorption microCT (high-resolution computed tomography or microtomography), and laser-scanning confocal microscopy (visible wavelength) were used to study a fragment of the keel of a tooth of the sea urchin Lytechinus variegatus. Stripes observed in the phase-contrast images of the fragment were also seen in confocal micrographs. MicroCT showed that the stripes were due to two parallel planar arrays of low-absorption channels within the bulk of the keel. In the phase microradiographs, maximum contrast stripes appear when a channel image from one row coincides with a channel image from the second row; otherwise, contrast is minimal. Long channels do not appear to have been observed previously in keels of sea urchin teeth.

[1]  T Takeda,et al.  Blood vessels: depiction at phase-contrast X-ray imaging without contrast agents in the mouse and rat-feasibility study. , 2000, Radiology.

[2]  M. Balooch,et al.  Three‐Dimensional Morphometry of the L6 Vertebra in the Ovariectomized Rat Model of Osteoporosis: Biomechanical Implications , 2000, Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research.

[3]  E Castelli,et al.  Low-dose phase contrast x-ray medical imaging. , 1998, Physics in medicine and biology.

[4]  S. Wilkins,et al.  Phase-contrast imaging of weakly absorbing materials using hard X-rays , 1995, Nature.

[5]  Ian Foster,et al.  A high-throughput x-ray microtomography system at the Advanced , 2001 .

[6]  P. Cloetens,et al.  Holotomography: Quantitative phase tomography with micrometer resolution using hard synchrotron radiation x rays , 1999 .

[7]  S. R. Stock,et al.  X-ray microtomography of materials , 1999 .

[8]  G. G. Stokes.  "J." , 1890, The New Yale Book of Quotations.

[9]  E. Pisano,et al.  Diffraction enhanced x-ray imaging. , 1997, Physics in medicine and biology.

[10]  J. Kinney,et al.  Pore geometry in woven fiber structures: 0°/90° plain-weave cloth layup preform , 1998 .

[11]  M. Stauber,et al.  On the ultrastructure and the supposed function of the mineralizing matrix coat of sea urchins (Echinodermata, Echinoida) , 1989, Zoomorphology.

[12]  Peter Cloetens,et al.  Study of the interaction of a short fatigue crack with grain boundaries in a cast Al alloy using X-ray microtomography , 2003 .

[13]  P. Cloetens,et al.  Phase objects in synchrotron radiation hard x-ray imaging , 1996 .

[14]  A. Snigirev,et al.  On the possibilities of x-ray phase contrast microimaging by coherent high-energy synchrotron radiation , 1995 .