S U M M A R Y On Earth, oceanic plates subduct beneath a variety of overriding plate (OP) styles, from relatively thin and negatively buoyant oceanic OPs to thick and neutrally/positively buoyant continental OPs. The inclusion of an OP in numerical models of self-consistent subduction has been shown to reduce the rate that subducting slabs roll back relative to the equivalent single plate model...

[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...

A method for preparation of highly active mammalian ribosomal subunits is described, which yields 60S subunits containing no more than 33% protein. It is suggested that the composition of these subunits corresponds closely to that of Escherichia coli 50S subunits. Data on the composition of bacterial and mammalian ribosomal subunits recovered from CsCl are given. It is shown that the commonly e...

We investigate the buoyant mass of bacterial cells in real time with the suspended microchannel resonator (SMR) as the population recovers from an osmotic shock. The density of the culture medium is chosen such that the bacteria initially have a positive buoyant mass which becomes negative as they recover from the hyperosmotic stress. This behavior can be used to differentiate between an antibi...

We find that tracer material can be concentrated into invariant regions of flows due exclusively to transient effects, as are produced when tracers temporarily become more buoyant than the surrounding fluid. This can occur either as a single event, e.g., if the tracer is initially weakly buoyant, or under periodic forcing, e.g., when external effects (such as solar heating) change the tracer de...

natural convection between vertical parallel plates occurs frequently in applications such as solar collectors and cooling of electronic instruments. the problem is a two dimensional developing buoyant flow. in this work, the two dimensional conservation equations are solved numerically for constant wall temperature and constant wall heat flux. the results for the local nusselt number at the du...

Numerous factors affect the distribution of mangrove plants. Most mangrove species are typically dispersed by. water-buoyant propagules, allowing them to take advantage of estuarine, coastal and ocean currents both to replenish existing stands and to establish new ones. The direction they travel depends on sea currents and land barriers, but the dispersal distance depends on the time that propa...

are heterogeneous with respect to molecular weight, buoyant density, and thermal stability. This finding constitutes evidence against unique points of breakage during DNA isolation. The variation in buoyant density suggests a local compositional heterogeneity in the chromosomal region of certain markers. The variation in molecular weight provides an explanation for the results of certain transf...

Buoyancy of Phaeocystis globosa Scherffel (Prymnesiophyceae) colonies was investigated by measuring the vertical distribution of colonies in quiescent water where convection had been removed. Over 60% of the colonies exhibited negative buoyancy regardless of light condition or growth phase. Positively and neutrally buoyant colonies lost their buoyancy in the dark, but regained buoyancy upon ret...