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).
ascending colon-the part of the large intestine that ascends from the cecum to the transverse colon. descending colon-the part of the large intestine that descends from the transverse colon to the sigmoid colon. sigmoid colon, sigmoid flexure-the s-shaped curve between the descending colon and the rectum.