Remembrance of Experiments Past: Analyzing Time Course Datasets to Discover Complex Temporal Invariants

In a ceramic housing, a silicon wafer is held centered with respect to the housing by a flat tensioning ring having three protrusions on its inner periphery and three protrusions on its outer periphery, the three protrusions on the outer periphery being in contact with the inner wall of the housing, the three protrusions on the inner periphery being in contact with the outer edge surface of a carrier disc on which the wafer is securely mounted.