Search results
Results From The WOW.Com Content Network
Hydrostatic weighing, also referred to as underwater weighing, hydrostatic body composition analysis and hydrodensitometry, is a technique for measuring the density of a living person's body. It is a direct application of Archimedes' principle , that an object displaces its own volume of water.
A wide variety of body composition measurement methods exist. The gold standard measurement technique for the 4-compartment model consists of a weight measurement, body density measurement using hydrostatic weighing or air displacement plethysmography, total body water calculation using isotope dilution analysis, and mineral content measurement by dual-energy X-ray absorptiometry (DEXA). [1]
The figure for water fraction by weight in this sample was found to be 58 ±8% water for males and 48 ±6% for females. [4] The body water constitutes as much as 75% of the body weight of a newborn infant, whereas some obese people are as little as 45% water by weight. [5] This is due to how fat tissue does not retain water as well as lean tissue.
"The majority of the adult body is water, up to 60% of your weight," says Schnoll-Sussman, adding that the average person's weight can fluctuate one to five pounds per day due to water.
And, since the concentration of 18 O in the body's water is measured after the labeling dose is given, we also know how much of the tagged oxygen left the body in the water. (A simpler view is that the ratio of deuterium to 18 O in body water is fixed, so total loss-rate of deuterium from the body multiplied by this ratio, immediately gives the ...
Similarly, calculated measurements of renal function (such as the Cockcroft-Gault formula) are unlikely to reflect actual activity of the kidney, as these calculations were developed for patients in whom the circulatory system correlates with the body weight; this relation is lost in a post-hemicorporectomy patient. [citation needed]
For a given solution, osmolarity is slightly less than osmolality, because the total solvent weight (the divisor used for osmolality) excludes the weight of any solutes, whereas the total solution volume (used for osmolarity) includes solute content. Otherwise, one litre of plasma would be equivalent to one kilogram of plasma, and plasma ...
The water equivalent is calculated for the following: Meter water equivalent, a standard measure of cosmic ray attenuation in underground laboratories;