1 You have signs of infection, such as: 2  Increased pain, swelling, warmth, or redness around the bite. 3  Red streaks leading from the bite. 4  Pus draining from the bite.  A fever.
A negative index of refraction due to three-dimensional chirality is demonstrated for abilayered metamaterial based on pairs of mutually twisted planar metal patterns in parallel planes, which alsoshows negative electric and magnetic responses and exceptionally strong optical activity and circular dichro-ism.
In optics, the refractive index or index of refraction n of a material is a dimensionless number that describes how light propagates through that medium. It is defined as. where c is the speed of light in vacuum and v is the phase velocity of light in the medium. For example, the refractive index of water is 1.333, meaning that light travels 1.333 times faster in a vacuum than it does in water.