In stochastic processes, chaos theory and time series analysis, detrended fluctuation analysis (DFA) is a method for determining the statistical self-affinity of a signal.
Sore throats caused by tonsillitis or streptococcus may trigger a canker sore even after the initial throat condition has subsided. Also known as an aphthous ulcer, canker sores are painful and unsightly, but they are not contagious.
You may have a canker sore if you have: 1  A painful sore or sores inside your mouth -- on the tongue, on the soft palate (the back portion of the roof of your mouth), or inside your cheeks.nlike canker sores, cold sores are caused by a virus and are extremely contagious. Also, cold sores typically appear outside the mouth -- usually under the nose, around the lips, or under the chin -- while canker sores occur inside the mouth.