What causes elevated AST levels? Causes of elevated aspartate aminotransferase, or AST, levels include a heart attack; liver, kidney or lung damage; medicines; high doses of vitamin A; and mononucleosis, states WebMD. Normal levels for adult women and men range between 10 and 36 units per liter and 14 and 20 units per liter respectively.
In 1041, movable clay type was first invented in China. Johannes Gutenberg, a goldsmith and businessman from the mining town of Mainz in southern Germany, borrowed money to invent a technology that changed the world of printing.
Movable type is the system of printing and typography using movable pieces of metal type, made by casting from matrices struck by letterpunches. Movable type allowed for much more flexible processes than hand copying or block printing.