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.
Braces and canker sores. Most people get canker sores â those annoying little ulcers inside of your mouth â occasionally, but they can be especially painful and irritating to wearers of orthodontic braces. The exact cause of canker sores is unknown, but contrary to popular belief, they are not the result of a bacterial or viral infection, nor are they contagious.