Medical Definition of dorsiflexion. : flexion in a dorsal direction; especially : flexion of the foot in an upward directionâcompare plantar flexion.
Willis Tower. The Willis Tower, built as and still commonly referred to as Sears Tower, is a 108-story, 1,450-foot (442.1 m) skyscraper in Chicago, Illinois, United States.
The architectural firm of Skidmore, Owings & Merrill was responsible for the design of the tower, with Bruce Graham serving as architect and Fazlur Khan as structural engineerâthe same team that built Chicagoâs tallest building, the Willis Tower (formerly the Sears Tower). The John Hancock Center was completed in 1970, and its gently sloping black steel form remains one of the most-recognizable structures in Chicagoâs famed skyline. The John Hancock Center (centre building) on North Michigan Avenue in Chicago. A bold form was chosen for the Hancock Center. The tapered rectangular tubeâwith giant trusses on each of the four sidesâreadily shows how the building is supported.