On Blow-Ups and Injectivity of Quivers
  This work connects the idea of a "blow-up" of a quiver with that of injectivity, showing that for a class of monic maps $\Phi$, a quiver is $\Phi$-injective if and only if all blow-ups of it are as well. This relationship is then used to characterize all quivers that are injective with respect to the natural embedding of $P_{n}$ into $C_{n}$. 
Will Grilliette, Deborah E. Seacrest, Tyler Seacrest
math.CO math.CT