diurnal variation


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Related to diurnal variation: diurnal variation of temperature

diurnal variation

1 the variability of output or excretion of a substance during the day versus the night or over a 12-hour interval.
2 expected high and low levels of a substance during a 24-hour period. For example, blood cortisol is highest in the morning and lowest in the early evening.
References in periodicals archive ?
First, far more lightning occurs over land, and, second, the diurnal variation of the lightning flash count follows the sun (http://science.
However, it is unknown whether diurnal variations in renal function would be sufficient to cause rather pronounced relative changes in hs-cTnT in the normal range.
Diurnal variations in summer season precipitation in India.
20,21) Others concluded that any variation with the resistance was not in phase with the diurnal variation in tension.
Due to the natural diurnal variation in serum testosterone levels, the guidelines recommend collecting the sample in the early morning.
The aim of this study is to find out the diurnal variation in cardiovascular endurance performance.
In contrast, there are few studies focused on measuring the seasonal and/or diurnal variations of heat and water vapour exchanges in the grasslands of the semi-arid region of Brazil and none for the state of Pernambuco.
We tried to find out the seasonal and diurnal variations in cases of death due to electrocution, and we observed a characteristic seasonal variation.
If an older, phakic patient has clinically significant FCED, with stromal and epithelial oedema and/or significant diurnal variation in symptoms, the decision to undertake simultaneous or closely sequential phacoemulsification and DSAEK is easy.
Diurnal variation of hematology parameters in healthy young males: the Bispebjerg study of diurnal variations.
1) and different tissues including roots stems leaves and petals were sampled; and the flowering petals of diurnal variation were taken every 3h from 6:00 to 21:00.