Seasonal variation in human illumination exposure at two different latitudes.

摘要: The authors measured ambient illumination exposure in healthy volun teers San Diego, California (latitude 32° 43' N, n = 30), and Rochester, Minne sota 44° 1'N, 24), during each of the four quarters year, which were centered on solstices equinoxes. Subjects wore photosensors their wrists lapels (or foreheads while bed) 24 h per day for an average 5-6 days quarter. maximum two readings was stored minute. Annual time spent outdoor (≥ 1000 lux) significantly higher Diego than it Rochester (p <.04). Daily durations at or exceeding thresholds 1,10,100,1000, 10,000 lux highly seasonal sample as a whole < .01 1 lux, p .0001 other thresholds). Seasonal variation far more pronounced (interaction .001) but remained significant ≤ .03). ind...