Abstract: A positional tracking system used in a virtual reality environment in which multiple users may freely and unrestrictedly explore an environment without affecting position tracking. Receivers mounted to the user in several locations may be accurately tracked regardless of the position of the user and other users in the system. A plurality of transmitters may transmit wide band signals to one or more receivers on a user. Each receiver may receive the wide band signals from the plurality of transmitters, process those signals, and determine a receiver location based on the received signals. The signals themselves may be wide band signals, for example in the range of 3 GHz to 10 GHz. The wide band signals may include identifier information and a pulse for determining a time-of-flight between the transmitter and receiver.

Abstract: A combined physical and virtual environment in which a user's position in a physical environment is displayed in an offset position within the virtual environment. The offset is determined based on mapping between the physical environment and the virtual environment and offsets generated for a user position and direction as a user moves throughout the physical environment. The physical environment and corresponding virtual environment may have a different layout. The offsets are used to correlate portions of the physical environment and virtual environments together so that a user does not realize the differences between the environments. By providing offsets in this manner, an enclosed physical environment may be used to provide an expanded and unlimited virtual environment for user to navigate and explore.

Abstract: In part, the disclosure related to systems and methods of merging a simulation experience with physical objects and sensory stimuli generated outside of the simulation in a controlled physical environment to enhance the simulated experience.

Abstract: Disclosed is a compound which inhibits binding between a target protein and a macromolecular ligand of the target protein. The compound comprises a targeting group, an attaching group and, optionally a linker group. In one aspect of the invention, the targeting group is a moiety that binds non-covalently to a surface of the target protein with a Kd of greater than about 0.1 ?M and within sufficient proximity to the target protein/macromolecular ligand binding site to inhibit binding between the target protein and the macromolecular ligand. In another aspect of the invention, targeting group is degradable in vivo. In yet another aspect of the invention, the compound comprises a linker group that is cleavable in vivo.