Discrete Mathematics/Functions and relations. This article examines the concepts of the function and the relation. A relation is any association or link between elements of one set, called the domain or (less formally) the set of inputs, and another set, called the range or set of outputs.
Sleep deprivation. Sleep deprivation is the condition of not having enough sleep; it can be either chronic or acute. A chronic sleep-restricted state can cause fatigue, daytime sleepiness, clumsiness and weight loss or weight gain. It adversely affects the brain and cognitive function.
Research also has shown that people who sleep less and still manage to lose weight will lose less actual fat. Like other aspects of sleep loss, the sleep-hormone-weight gain dynamic is more complicated for women because of monthly hormonal shifts associated with menstruation. According to a poll by the National Sleep Foundation, more than 70 percent of menstruating women experience disrupted sleep.