<http://schema.org/image_url>
"http://media.al.com/news_huntsville_impact/photo/prostatecancerinfographic-f94c7520b1081e7d.jpg"^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.al.com/news/huntsville/index.ssf/2014/07/free_prostate_screening.html>