
Keywords: نوزاد; RR; RR interval; SD1; short axis of the Poincaré plot; SD2; long axis of the Poincaré plot; PI; Porta's index; EI; Ehlers index; SKG; the Sapina-Kramaric-Garcin index; ANS; the autonomic nervous system; Autonomic nervous system; Newborn; Stress; Poinc