Lasers can cause damage in biological tissues, both to the eye and to the skin, due to several mechanisms. Thermal damage, or burn, occurs when tissues are heated to the point where denaturation of proteins occurs. Another mechanism is photochemical damage, where light triggers chemical reactions in tissue.
March 9: Teams are allowed to begin negotiating with other teamsâ players who are set to become unrestricted free agents at the end of the league year. This is the first time the NFL is providing a window to negotiate with other teamsâ free agents prior to the start of free agency.
How the NFL franchise tag works. NFL. February 28, 2017 1:46pm EST February 28, 2017 9:31am EST NFL free agency really begins when the window opens for teams to use franchise tags or transition tags on players. Here's how it works. Kirk Cousins (Getty Images)