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.
A canker sore (aphthous stomatitis) is an illness that causes small ulcers to appear in the mouth, usually inside the lips, on the cheeks, or on the tongue. What causes aphthous stomatitis (canker sores)? The exact cause of this disease is not known.