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.
where F is the power in dioptres, n and nâ² are the refractive indices of the media on each side of the surface and r is the radius of curvature of the lens or mirror surface, in metres. This equation forms part of the fundamental paraxial equation. For a spectacle lens in air (n = 1) the power of the surface becomes.