In various examples, an apparatus includes an apparatus configured for implantation within a body of a patient. 5, and comprises a plurality of protuberances 13, depressions 14 or both; and wherein the inner layer 12 and the outer layer 11 are in substantially continuous, thermally conductive contact. The void pipes are positioned in a trench atop one another so that the cylindrical axis of a bottom void pipe is substantially vertically aligned with the cylindrical axis of a top void pipe, and the cylindrical axis of a middle void pipe is offset from those of the bottom and top void pipes. The focus state determination unit includes: a unit for calculating a change of the focus evaluation value; and a unit for determining the focus state information to be displayed by referring to a table that associates a combination of the change of the focus evaluation value, the focus evaluation value, and the target value with the display color of the focus state information. The additional information is information that includes at least one of posts at respective times and information regarding the posting subject.