ARKHANGELSK, June 25. /TASS/. A comprehensive survey of the Arctic Floating University expedition participants began in Arkhangelsk, the expedition team's deputy scientific leader, Anna Trofimova, told TASS. For the first time this year, the expedition will survey the quality of sleep.

"The ship departs on July 1, but the research has started already - we are completing the preliminary, pre-background stage. The participants have undergone the first cycle of tests: we have done EEG (electroencephalogram) tests, and a number of other tests," she said. "This year, the research range has expanded - we are using new methods, including a questionnaire to assess sleep quality before the voyage, during its core moments, and during particularly difficult periods."

The expedition will feature those who have participated in earlier voyages and those who are traveling for the first time. "Thus, we will be able to monitor their individual dynamics," she added.

The study of human adaptation to the high-latitude Arctic's conditions is conducted by Alexandra Yelfimova, a senior researcher at the Endocrinology Laboratory of the Professor Tkachev Federal Research Center for Comprehensive Arctic Studies (the Russian Academy of Sciences' Urals Branch). In the voyage participants, specialists will register heart rate variability; they will study the content of catecholamines and hormones in saliva, urine and blood serum to identify any correlations between these parameters.