See the attached PDFs.  Region 1 has 2<p<4, 3.5<dE/dx<4; Region 2 has 2<p<4, 2.4<dE/dx<3; Region 3 has 7<p<11, 3.6<dE/dx<4.1; and Region 4 has 7<p<11, 2.75<dE/dx<3.25 (see plot below).  For the single-electron simulations, no dE/dx cut was used.  The pdfs without an R are show the data and simulation plots for the final set of cuts (including, for the data, dE/dx cuts).