Densification in highly porous, isothermal firn occurs primarily by Newtonian sliding on grain boundaries, but the coordination number increases with density and restricts further sliding. At a relative density of about 0.6 the coordination number approaches 6 and sliding ceases to be a primary mechanism of densification; the resulting decrease in densification rate causes the critical point in...

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...

PURPOSE To examine the impact of making weight on aerobic work capacity and cognitive processes in a group of professional jockeys. METHODS Nine male jockeys and 9 age-, gender-, and BMI-matched controls were recruited to take part in two experimental trials, conducted 48 hr apart. The jockeys were asked to reduce their body mass by 4% in the 48 hr between trials, and controls maintained usua...

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...

We aimed to evaluate whether an intervention program emphasizing in increased fluid intake can improve exercise performance in children exercising in the heat. Ninety-two young athletes participated in the study (age: 13.8 ± 0.4 years, weight: 54.9 ± 1.5 kg). Thirty-one (boys: 13, girls: 18) children served as the control group (CON) and 61 (boys: 30, girls: 31) as the intervention (INT). Volun...

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 ...