Double-contrast barium enema Double-contrast barium enema A double-contrast barium enema is a form of contrast radiography in which x-rays of the colon and rectum are taken using two forms of contrast to make the structures easier to see. A liquid containing barium (that is, a radiocontrast agent) is put into the rectum. Barium is a silver-white metallic compound that outlines the colon and rectum on an x-ray and helps show abnormalities. Air is also put into the rectum and colon to further enhance the x-ray. Double-contrast barium enemas are less invasive than a colonoscopy and have comparatively fewer issues in a viable large
Chemical element February 2010. The heaviest element that is believed to have been synthesized to date is element 118, oganesson, on 9 October 2006, by the Flerov Laboratory of Nuclear Reactions in Dubna, Russia. Tennessine, element 117 was the latest element claimed to be discovered, in 2009. On 28 November 2016, scientists at the IUPAC officially recognized the names for four of the newest chemical elements, with atomic numbers 113, 115, 117, and 118. The following sortable table shows the 118 known chemical elements. Chemical element A chemical element is a species of atoms having the same number of protons in their