University scientists bring the lab to the courtroom   

To teach his students about forensic science, Wes Watson, an entomology professor at N.C. State University, likes to borrow a scene from an early episode of “CSI: Las Vegas.” In the episode, Gil Grissom, the night shift supervisor of the “CSI” team pulls a cattle grub from the bullet wound of a shooting victim lying on the autopsy table. “Genus hypoderma,” Grissom, the show’s bug man, tells Dr. Al Robbins, the fictional Las Vegas chief medical examiner. “These are normally found in the intestinal tract of cows. These maggots aren’t found in humans.” The cattle grub is key to solving the TV case, because it leads Grissom to discover that the bullet was made from frozen ground beef.