(Portland, OR)  --  A man is facing charges after allegedly slashing at a security guard with a knife.  Police arrested 40-year-old Aaron Deatley of Vancouver for the incident Friday afternoon outside an outdoor retailer off North Hayden Meadows Drive.  Police say Deatley cut the security guard on the forearm with a knife following a brief struggle.  The security guard is expected to survive.  Deatley was arrested on charges of first-degree robbery and second-degree assault.