To better understand how elephant seals (Mirounga angustirostris) use negative buoyancy to reduce energy metabolism and prolong dive duration, we modelled the energetic cost of transit and deep foraging dives in an elephant seal. A numerical integration technique was used to model the effects of swim speed, descent and ascent angles, and modes of locomotion (i.e. stroking and gliding) on diving...

Recently, the economic feasibility of drilling a horizontal well improved drastically due to advances in drilling technology. Advantages of horizontal wells over vertical well applications have been confirmed by many scientists(1-4) and operators(5-7). Horizontal wells showed many distinct advantages over vertical ones such as improvement of well productivity, attenuation of sand production, an...

Evidence is increasing to suggest that a major activity of roots is to redistribute soil water. Roots in hydraulic contact with soil generally either absorb or lose water, depending on the direction of the gradient in water potential between root and soil. This leads to phenomena such as "hydraulic lift" where dry upper soil layers drive water transfer from deep moist layers to the shallow rhiz...

was vacuum-formed from one piece of clear tenite (Lus-Trus Corporation, Ypsilanti, Michigan). The trough is 5 cm wide, 10 cm deep, and filled with water to a depth of 5 cm. The trough is rotated 2 rpm on a turntable in a darkened chamber. The alternative of rotating the stimulus light, photoconductors, and electrodes around the stationary trough seemed less convenient. The stimulus light is a d...

Deep-water renewal in Lake Baikal (Siberia), the world’s deepest lake and largest lake by volume, is relatively fast. Water age calculated from tritium and helium as well as from chlorofluorocarbons does not exceed 19 yr. Relative saturation of dissolved oxygen typically exceeds 80%. The equation of state of Baikal water was determined including the effect-of dissolved ions and silicic acid. Ba...

We show that ripples on the surface of deep water which are driven parametrically by monochromatic vertical vibration represent ensembles of oscillating solitons, or quasiparticles, rather than waves. The horizontal mobility of oscillons determines the broadening of spectral lines and transitions from chaos to regular patterns. It is found that microscopic additions of proteins to water dramati...