Samples of urine which have been collected by ureteric catheterization are necessarily small in volume, often only a few drops. In order to determine the efficiency of kidney function it may be necessary to measure the specific gravity of these small samples, but it is impossible to use the hydrometer method, which requires a minimum of about 50 ml. of urine. Methods involving the suspension of...

This study explores the extent to which richer central cities are associated with slower suburban sprawl. The authors use a unique approach to categorizing municipalities in urbanized areas based on their relative densities. Richness is measured in terms of the central city’s relative share of high-income households. The central finding (both for the decade from 1990 to 2000 and for 2000 to 200...

One of the factors which affects the gas lift performance is specific gravity of a lift gas (or the Molecular weight), which can influence the gas solubility in oil and has a direct effect on the gas lift performance. There are some previous researches which have included the lift gas specific gravity in their modeling, but in none of them, a comprehensive research about the effect of lift gas ...

It is difficult to describe hydration status and hydration extremes because fluid intakes and excretion patterns of free-living individuals are poorly documented and regulation of human water balance is complex and dynamic. This investigation provided reference values for euhydration (i.e., body mass, daily fluid intake, serum osmolality; M +/- SD); it also compared urinary indices in initial m...

This controlled hydration study was designed to validate the substitution criteria used by the Substance Abuse and Mental Health Services Administration (SAMHSA) to classify a workplace urine specimen as inconsistent with normal human urine. Study participants (n = 56) ingested at least 80 oz (2370 mL) of fluid over a 6-h period, 40 oz during the first 3 h (DOT hydration protocol) and 40 oz dur...