eccentric connectivity index has been found to have a low degeneracy and hence a significantpotential of predicting biological activity of certain classes of chemical compounds. wepresent here explicit formulas for eccentric connectivity index of various families of graphs.we also show that the eccentric connectivity index grows at most polynomially with thenumber of vertices and determine the ...

Hemangiopericytoma is a vascular tumor that is rarely seen in the nose and paranasal sinuses. Biological behavior of these tumors is not completely known, and their natural history is not predictable. This case report presents a patient with a sinonasal hemangiopericytoma. Diagnosis and management of these uncommon tumors is discussed.