Buoyancy acting on plankton, i.e. the difference in specific gravity between plankton and the ambient water, is a function of salinity and temperature. From specific gravity measurements of marine fish eggs salinity appears to be the only determinant of the buoyancy indicating that the thermal expansions of the fish egg and the ambient seawater are equal. We analyze the mechanisms behind therma...

In present paper, a numerical analysis for a rectangular cavity filled with a anisotropic porous media has been studied. It is assumed that the horizontal walls are adiabatic and impermeable, while the side walls of the cavity are maintained at constant temperatures and concentrations. The buoyancy force that induced the fluid motion are assumed to be cooperative. In the two extreme cases o...

The lack of success in predicting the recruitment of fish may to some extent arise from insufficient knowledge of processes affecting egg and larval survival (Chambers and Trippel, 1997). In this context, the quality of eggs and larvae [cf. definitions given in Brooks et al. (Brooks et al., 1997)] and their capacity to develop properly are often mentioned as important factors along with the cor...

Loggers were attached to free-ranging Brünnich's guillemots Uria lomvia during dives, to measure swim speeds, body angles, stroke rates, stroke and glide durations, and acceleration patterns within strokes, and the data were used to model the mechanical costs of propelling the body fuselage (head and trunk excluding wings). During vertical dives to 102-135 m, guillemots regulated their speed du...

the objective of the present study was to develop floating microspheres of cefpodoxime proxetil in order to achieve an extended retention in the upper git, which may result in enhanced absorption and thereby improved bioavailability. the microspheres were prepared by non-aqueous solvent evaporation method using polymers such as hydroxyl propyl methyl cellulose (hpmc k 15 m), ethyl cellulose in ...

Evidence for the parity-breaking nature of the magnetic buoyancy instability in a stably stratified gas is reported. In the absence of rotation, no helicity is produced, but the nonhelical state is found to be unstable to small helical perturbations during the development of the instability. The parity-breaking nature of this magnetohydrodynamic instability appears to be the first of its kind a...

[1] The thermal boundary layer beneath continental cratons extends into the Earth’s mantle to depths of at least 200 km. It has been proposed that chemical depletion of the lithospheric mantle during partial melting offsets the effect of increased density from conductive cooling, resulting in neutral buoyancy with respect to the underlying asthenosphere. Mineral compositions of garnet peridotit...

The role of a buccal gas bubble, held while performing aquatic surface respiration (ASR; ventilating the gills with surface water during hypoxia), was examined in benthic, intertidal Australian gobies (Favonigobius tamarensis, F. exquisitus, Pseudogobius olorum, Chlamydogobius sp., Mugilogobius paludis, Cryptocentroides cristatus and Arenigobius bifrenatus). Analyses of the forces of lift and w...

A computational study has been made for a three dimensional double diffusive convection with molten Pb-Sn by using finite volume method. In this work, two vertical walls have different temperature and different concentration while remaining walls are adiabatic. Buoyancy ratio, which changes between N = -0.1 and -10, is the main governing parameter during work. Other parameters are taken as fixe...

The feasibility of a buoyancy-based control approach for regulating the horizontal position of atmospheric balloons in stratified and turbulent environmental flows is investigated. Two different control rules are considered, and numerical investigations are performed for a challenging case related to tropical cyclones. The low energy requirement of the buoyancy-based control approach allows con...