[
 {
  "value": "87048",
  "sigma": "144",
  "source": "Czeisler et al., Science 284, 2177 (24.18 +/- 0.04 h, mean +/- SEM), in seconds",
  "year": "1999",
  "field": "biology",
  "id": "Q17",
  "unit": "s",
  "quantity": "human circadian free-running period",
  "grade": "primary abstract plus citing paper, PRIOR-ART row 21",
  "bound_low": "",
  "bound_high": "",
  "recalled": "no"
 },
 {
  "value": "2531520",
  "sigma": "4320",
  "source": "Bull et al., npj Digit Med 2, 83 (mean cycle 29.3 d, rounding 0.05 d), in seconds",
  "year": "2019",
  "field": "biology",
  "id": "Q18",
  "unit": "s",
  "quantity": "human menstrual cycle mean length",
  "grade": "recalled (not found in the fetched results), PRIOR-ART row 21",
  "bound_low": "",
  "bound_high": "",
  "recalled": "yes"
 }
]