Sigma (Ï) values are experimental values that are assigned to substituents that take into account both a substituentâs resonance and inductive effects. The sigma value has a sign (+ or -) and a magnitude or numerical value.
Dr. Yu found that prone sleeping was strongly associated with all kinds of charged dreams, such as having sex, being locked up, being smothered or unable to breathe, having a love affair with a celebrity, seeing a UFO, and being naked.
1 Genetics: Researchers have found a genetic basis for narcolepsy, a neurological disorder of sleep regulation that affects the control of sleep and wakefulness. 2  Night shift work: People who work at night often experience sleep disorders, because they cannot sleep when they start to feel drowsy.