Jupiterimages/Brand X Pictures/Getty Images. Panic is a natural reaction when you're served with a subpoena, but as far as legal documents are concerned, a subpoena duces tecum is one of the more innocuous ones you can encounter.
Circadian rhythms are biological oscillations that recur with a period of approximately one day. Health issues related to circadian rhythms include jet lag, shift work, seasonal depression, and time-of-day variations in response to medical treatments.
A main challenge of shift work is that it forces you to sleep against the clock. You have an internal body clock in your brain that produces circadian rhythms. The word circadian means to occur in a cycle of about 24 hours. These rhythms act like messages that regulate various body functions.