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.
Canker sore. In some cases, the exact cause of a canker sore is unknown, but trauma or injury to the mouth or oral soft tissues may be the culprit. Other possible causes are food sensitivities, spicy, salty or acidic foods, vitamin B deficiency, hormonal shifts and stress. Cold sore.