Axenic cultures of 25 species of unicellular marine algae were tested for their ability to utilize nine common amino acids, supplied at high concentrations in batch culture, as a nitrogen source; most species were able to use several amino acids, although growth was often slower than on nitrate nitrogen. The...
The hepatotoxic alkaloids known to occur in tansy ragwort (Senecio jacobaea L.) are also present in honey produced from the nectar of this species. These alkaloids, which include senecionine, seneciphvlline, jacoline, jaconine, jacobine, and jacozine, are potentially carcinogenic, mutagenic and teratogenic and may pose health hazards to the human consumer.
Uptake of [14C]glycine by various size fractions of natural plankton communities was measured to determine if phytoplankton can compete effectively with other members of the plankton community for the free amino acids in seawater. The simultaneous occurrence of glycine uptake, plant pigments, and photosynthetic activity in the same size fractions,...
Fluxes of sulphur dioxide to wheat were measured over two growing seasons. The deposition velocity, vg, depended primarily on affinities of surfaces for SO2 and varied from less than 0.1 to about 1.5cms−1. Stomata were an important sink, and diurnal changes in stomatal resistance accounted for most of the variation...
We have developed a new approach to the theory of linear dichroism in partially ordered systems. The description of the partially ordered ensemble uses a density of states function, D(θ, ϕ, Δ), which gives the probability that the direction of polarization for incident polarized light has spherical angles θ and...
Paleomagnetic directions from the Eocene Tillamook Volcanic Series of the Oregon Coast Range
point 460 clockwise from the expected Eocene field direction. Potassium argon dating of six dikes and
flows from this formation yields a mean age of 44.3 ± 0.6 m.y. These results establish that the Oregon
coastal block...
We have expanded on the results of an earlier paper [J. Chem. Phys. 72, 221 (1980)] which deals with a method for determining the response of a static, partially ordered ensemble of molecules to various types of electromagnetic probes. In this paper we consider types of spectroscopy whose response depends...
An exact expression for the remotely sensed reflectance (RSR, upwelling radiance divided by downwelling scalar irradiance) just beneath the surface of the ocean is derived from the equation of radiative transfer. It is shown that the RSR at a given depth in the ocean depends only on the inherent optical...
This review documents the advances in our knowledge of the oceanic internal wave field during the past quadrennium. Emphasis is placed on studies that deal most directly with the measurement and modeling of internal waves as they exist in the ocean. Progress has come by realizing that specific physical processes...