All of the nation's top Division II programs will be back on the mat  this weekend.    Top-ranked North Dakota State, which took part in the rugged Cliff Keen Invitational last weekend in Las Vegas, will compete in the St. Cloud Invitational on Saturday.    The Bison finished 16th in Las Vegas, a meet that featured mainly Division I programs.    No. 2 South Dakota State is scheduled to wrestle Carleton and Concordia in a triangular on Friday in Northfield, Minn.    Third-ranked Central Oklahoma, which also competed in Vegas, is scheduled to wrestle Lindenwood on Friday at home.    Central Oklahoma's Muhammed Lawal continued his strong early season showing at 197 pounds by finishing second to Lehigh's Jon Trenge in Vegas.    Central Oklahoma placed 18th in Vegas.    No. 4 Nebraska-Omaha will make the short trek to the Nebraska-Kearney Open on Saturday. UNO's Chad Wallace, ranked second, won the 197 title on Sunday at the Northern Iowa open. Teammate Zach Stalder placed second at 184.    Fifth-ranked Ashland (Ohio) is slated to compete at the Ohio Northern Invitational on Saturday.    No. 6 Pitt-Johnstown is scheduled to wrestle at the Clarion University Duals on Dec. 16.