Most Popular. An impact driver looks similar to a drill/driver but for one noticeable distinctionâinstead of a keyless chuck, it has a collet that accepts hex-shanked driver bits. This tool is specially engineered to do one job: drive screws, which it does faster and easier than any other tool. Impact drivers can drive long, large fastenersâincluding fat lag screwsâthat would stall the very best drill/driver.
Sigmoid colon. The sigmoid colon (pelvic colon) is the part of the large intestine that is closest to the rectum and anus. It forms a loop that averages about 35-40 cm in length. The loop is typically shaped like a Greek letter sigma (Ï) or Latin letter S (thus sigma + -oid).
Inflammatory bowel disease such as ulcerative colitis and Crohn's disease may occur here. Diverticulitis, in which little outpouchings of bowel form and become inflamed, is more common in the sigmoid than any other part of the bowel. Small growths called polyps, as well as cancers, also favour this site. The good thing about investigating sigmoid disease is that this part of the colon isn't far from the outside world. It is easy to pass a rigid sigmoidoscope into the anus and get a decent view.