Generalized models of thorium and particle cycling, data from Station P, and an inversion technique are used to obtain rate estimates of important biological and chemical transformations occurring in the water column. We first verify the inversion technique using an idealized data set generated by a finite difference model, and then apply the inversion technique to data from Station P. With the...

Diatoms and other phytoplankton play a crucial role in the global carbon cycle, fixing CO2 into organic carbon, which may then be exported to depth via sinking particles. The molecular diversity of this organic carbon is vast and many highly bioactive molecules have been identified. Polyunsaturated aldehydes (PUAs) are bioactive on various levels of the marine food web, and yet the potential fo...

[1] It is generally assumed that sinking particulate organic carbon (POC) constitutes the main source of organic carbon supply to the deep ocean’s food webs. However, a major discrepancy between the rates of sinking POC supply (collected with sediment traps) and the prokaryotic organic carbon demand (the total amount of carbon required to sustain the heterotrophic metabolism of the prokaryotes;...

We analyzed size-specific dry mass, sinking velocity, and apparent diffusivity in field-sampled marine snow, laboratory-made aggregates formed by diatoms or coccolithophorids, and small and large zooplankton fecal pellets with naturally varying content of ballast materials. Apparent diffusivity was measured directly inside aggregates and large (millimeter-long) fecal pellets using microsensors....

STATEMENT OF PROBLEM Unlike screw-retention type, fixture-abutment retention in Locking taper connection depends on frictional force so it has possibility of abutment to sink. PURPOSE In this study, Bicon® Implant System, one of the conical internal connection implant system, was used with applying loading force to the abutments connected to the fixture. Then the amount of sinking was measure...

-The size distribution of pelagic producers and the size and trophic position of consumers determine the composition and magnitude of sinking fluxes from the surface communities in a simple model of oceanic food webs. Picoplankton, the dominant producers in the model, contribute little to the sinking material, due primarily to the large number of trophic steps between picoplankton and the consu...

Phytoplankton require light for photosynthesis. Yet, most phytoplankton species are heavier than water and therefore sink. How can these sinking species persist? Somehow, the answer should lie in the turbulent motion that redisperses sinking phytoplankton over the vertical water column. Here, we show, using a reaction-advection-diffusion equation of light-limited phytoplankton, that there is a ...