Table 4.

Summary of Injury Mechanisms from Quaternary bTBI

Reference	In-vitro injury	RM	IM	IC	O	Summary
Noel and Tofilon, 1998	Radiation (x-ray)			X		X-ray induces neuronal apoptosis;  astrocytes secrete neuroprotective proteins
Haimovitz-Friedman  et al., 1994	Radiation (ionizing)			X		Radiation interacts with the cellular  membrane and induces apoptotic signals
Munshi and Jalali, 2002	–					Review of cell phone hazards
Christ and Kuster, 2005	–					Factors that affect energy absorption

RM, receptor mediated; IM, ion mediated; IC, intracellular signaling; O, other.