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In page X-ray:

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  • Shoe-fitting fluoroscopes were popularized in the 1920s, banned in the US in the 1960s, in the UK in the 1970s, and later in continental Europe.[citation needed]
  • Roentgen stereophotogrammetry is used to track movement of bones based on the implantation of markers[citation needed]
  • X-ray photoelectron spectroscopy is a chemical analysis technique relying on the photoelectric effect, usually employed in surface science[citation needed].