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This experimental schedule is not a dosing instruction.\nexposure: 3 mg once daily for three days at different circadian times; dim-light onset measured\nevidence_span: {\"source_cache\": \"artifacts/melatonin-research/18006583.abstract.txt\", \"locator\": \"Primary indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"9eb1409f6e4c58eadfaf1554930378e03860dc9dc1201de6d104b6de784758ea\", \"start_char\": 0, \"end_char\": 1518, \"text_sha256\": \"9eb1409f6e4c58eadfaf1554930378e03860dc9dc1201de6d104b6de784758ea\"}\n[melatonin-p18006583] A three pulse phase response curve to three milligrams of melatonin in humans. (2008). https://pubmed.ncbi.nlm.nih.gov/18006583/ DOI: 10.1113/jphysiol.2007.143180","model_system":"Double-blind counterbalanced phase-response experiment","directness":"author_interpretation","verification_status":"source_derived_draft","notes":"Exact curation-document quotation, not publisher quotation. 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