Foundation lumber

Once in awhile, I see treated lumber embedded in a concrete foundation wall. First of all, what are they designed for? and second, should they be sealed periodically? I see them exposed on occasion. (see pics)

Siding nailers

Agreed and each one should be made with pressure treated lumber as you stated, in areas that have termites it might need treated for that also if it is contact with the ground.

Anyone have any reading materials on lumber foundations?
Michel, if it is siding nailer, is there concrete behind the nailer?
It is vertically aligned. Why?
Thanks in advance.