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 sores may run in families, but they aren't contagious. Doctors don't know exactly what causes canker sores. Mouth injuries, stress, poor nutrition, food allergies and menstrual periods are some of the things that may increase your chances of getting a canker sore.