Several studies have documented the effect of latitude, season time of the day and altitude on the cutaneous production of vitamin D3.
To investigate the effects of latitude and time of day in Massachusetts and Florida, and to measure the maximal conversion of 7-DHC to previtamin D3 without the effects of skin pigmentation, we used triplicate, unlabeled, borosilicate ampoules (Sigma-Aldrich) containing 7-DHC in 700 μL ethanol (50 μg/mL).
The designs of both photovoltaic and photothermal systems requires detailed information on solar radiation flux incident on the Martian surface as a function of latitude, longitude, time of day and year.
Figure 32a shows the resulting Fe column injection rate as a function of latitude and time of year.
Along the west coast of North America, latitude, the time of exposure to low tide and the probability of coastal fog all combine to create a patchwork of physiological stresses for high intertidal species [57].
Along with demonstrating maximal conversion of 7-DHC to previtamin D3, this model examines the effects of season, latitude, and time of day on previtamin D3 production.
They found no association between CP and the risk of RRMS (OR: 0.8; 0.4 1.7) or PPMS (OR: 1.0; 0.3 3.7) when compared to healthy controls adjusting for latitude of residence at time of entry into active duty and education level [ 28].
The photosynthesis of vitamin D3 is dependent on the latitude, the time of day, the season of the year and the concentrations of atmospheric ozone and pollutants.
Factors that affect cutaneous production of vitamin D3 include latitude, season, time of day, air pollution, cloud cover, melanin content of the skin, use of sunblock, age and the extent of clothing covering the body.
Sunrise and sunset times were generated from mathematical models as a function of latitude, longitude, time zone, and day of year (http://www.sci.fi/∼benefon/sun.php3).sci.fi/∼benefon/sun.php3
