How to link a variable to vertices of a directed graph using bubles with different sizes

This Code produces a directed graph:

SeedRandom[12]; mat = RandomReal[{0, 2}, {5, 5}]; select[matrix_, lB_, uB_] := matrix*Map[Boole[lB <= # <= uB] &, matrix, {-1}]; sa = SparseArray[select[mat, .1, .4]]; weightedG = Graph[sa["NonzeroPositions"], EdgeWeight -> sa["NonzeroValues"],     DirectedEdges -> True, VertexLabels -> Automatic] 

I like to attach a variable:

emp = {10, 45, 2, 1, 49}; 

to each vertex using bubbles with different sizes based on the variable emp, that is, the bubble size of vertex 1 should be a normalized size (i.e., 10/107), for vertex 2 (45/107), and so on. Elements of the variable emp are associated with five vertices {1,2,3,4,5}, respectively.

The final directed graph should be one with vertices of different bubble sizes.