Upper gastrointestinal series tract in addition to barium, and this procedure is called double-contrast imaging. In this case the gas is referred to as the negative contrast medium. Traditionally the images produced with barium contrast are made with plain-film radiography, but computed tomography is also used in combination with barium contrast, in which case the procedure is called CT enterography. Various types of barium X-ray examinations are used to examine different parts of the gastrointestinal tract. These include barium swallow, barium meal, barium follow-through, and barium enema. The barium swallow, barium meal, and barium follow-through are together also called an upper gastrointestinal series
Colon classification Colon classification Colon classification (CC) is a system of library classification developed by S. R. Ranganathan. It was the first ever faceted (or analytico-synthetic) classification. The first edition was published in 1933. Since then six more editions have been published. It is especially used in libraries in India. Its name "colon classification" comes from the use of colons to separate facets in class numbers. However, many other classification schemes, some of which are completely unrelated, also use colons and other punctuation in various functions. In CC, facets describe "personality" (the most specific subject), matter, energy, space, and time (PMEST). These