  In this paper, we investigate the abilities of systems of self-assembling
tiles which can each pass a constant number of signals to their immediate
neighbors to create replicas of input shapes. Namely, we work within the
Signal-passing Tile Assembly Model (STAM), and we provide a universal STAM tile
set which is capable of creating unbounded numbers of assemblies of shapes
identical to those of input assemblies. The shapes of the input assemblies can
be arbitrary 2-dimensional hole-free shapes. This improves previous shape
replication results in self-assembly that required models in which multiple
assembly stages and/or bins were required, and the shapes which could be
replicated were more constrained, as well as a previous version of this result
that required input shapes to be represented at scale factor 2.
