John Shepherd (physicist)

John A. Shepherd (born 1962) is an American physicist, professor of epidemiology and population sciences and director of the "Shepherd Research Laboratory" at the University of Hawaii Cancer Center in Honolulu, Hawaii. He is an expert in the use of dual-energy X-ray absorptiometry (DXA) for quantitative bone and soft tissue imaging, and pioneered the use of 3D optical imaging of the whole body for quantifying body composition and associated diseases including cancer risk, obesity, diabetes, and frailty. In 2016, he was the President of the Board of the International Society for Clinical Densitometry.
Early life and education.
Shepherd was born in Austin, Texas in 1962. He studied engineering physics at Texas Tech University in Lubbock, Texas where he obtained his Bachelor of Science degree. He continued his education at the University of Virginia in Charlottesville, Virginia, where he received his PhD in engineering physics in 1993. He was the first to develop scintillating vapor-deposited Na(Tl) thin films for photon counting imaging detectors grown with a columnar structure for high spatial resolution. He did his postdoctoral studies in biophysics at the Princeton University, where he adapted a phosphor created for color TV to emit green light well matched to the absorption of modern solid state detectors with very fast light output.
Career.
Shepherd designs and develops dual-energy X-ray absorptiometry systems, mammography and 3D optical biomarkers used to evaluate the risk of osteoporosis, breast cancer, and obesity. He serves as the principal investigator for the National Institute of Diabetes and Digestive and Kidney Diseases funded Shape Up! Adults and Kids cohort.