The role of bicarbonate reabsorption and of transtubular chloride gradients in the bulk reabsorption of sodium and water by renal tubules can be tested in the isolated perfused kidney by perfusing with a medium from which bicarbonate has been omitted. Perfusion of the isolated rat kidney with an artificial medium in which bicarbonate is replaced by chloride results in a fall in fractional reabs...

The bound carbohydrates of noncataractous , decapsulated, human lenses have been examined. The hexoses and hexosamines of the water-soluble, water-insoluble nonmembrane, and membrane fractions of lenses from six age groups were determined by gas-liquid chromatography. The plasma membrane contains 60-70% of all bound carbohydrates, including glucose, galactose, mannose, fucose, glucosamine, and ...

models the water flooding of an oil reservoir [6]. Water flooding involves the injection of water, which is immiscible with oil, into certain wells of the reservoir to force oil out at others. In this case, s = s(x, t) is the saturation of water (i.e., the volume fraction of water in the total fluid, 0 < s d 1 ), and g= g(s) is the particle velocity of the water. Consequently, since the total v...

Water samples from the Scheldt estuary were collected in three fractions: (a) unfiltered water, (b) water filtered through a 50 ìm net and (c) water filtered through a 300 ìm net. Particles easily recognisable from the majority of the amorphous particles were isolated and their geometric dimensions measured. From the measurements, shape factors were calculated. Measurement of fractal dimensions...