Therefore, if you're planning a long journey, you should always apply for the Russian visa before you leave. It's possible to get a tourist visa support at any moment before your journey, however, you can only apply for a tourist visa not earlier than 90 days before the date of your first entry to Russia.
Serotonin is a common neuromediator in the brain. It belongs to the group of so-called biogenic amines, relatively simple chemicals that facilitate the transfer of signals between the cells of the body.
Various alterations in corresponding genes affect the levels of serotonin or sensitivity to serotonin and may cause behavioral changes. Changes in serotonin level can affect behavior. The level of serotonin is controlled by multiple mechanisms. Any changes in the genes involved may lead to serious consequences.