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Depot-specific adipocyte responses mean this is not a uniform browning effect.\nexposure: Cold exposure sufficient to induce shivering; FNDC5 and FGF21 treatment of human adipocytes\nevidence_span: {\"source_cache\": \"artifacts/cold-research/24506871.abstract.txt\", \"locator\": \"Indexed abstract; zero-based, end-exclusive Unicode character offsets\", \"file_sha256\": \"980c2630ed13bf2a55f813a6df483edb68a1d6370c0f1afdfcbc7df7817eb610\", \"start_char\": 0, \"end_char\": 1149, \"text_sha256\": \"980c2630ed13bf2a55f813a6df483edb68a1d6370c0f1afdfcbc7df7817eb610\"}\n[cold-p24506871] Irisin and FGF21 are cold-induced endocrine activators of brown fat function in humans. 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