14 research outputs found
Environmental studies data base development and data synthesis activities of the US Subseabed Disposal Program
The US Subseabed Disposal Program is assessing the scientific feasibility of subseabed emplacement of high-level nuclear wastes. Studies of disposal methods and of the barriers to radionuclide migration (canister, waste form and sediment) suggest that environmental information will be needed to address the impact of accidental release of radionuclides in the deep sea. Biological, physical, and geochemical data are being collected from field and laboratory studies as well as from literature searches. These data are being analyzed using a multicompartmental radionuclide transport model and appropriate physical oceanographic models. The data integrated into this framework will help answer two questions: what are the environmental effects of radionuclides which may be released in the deep sea, and what are the effects of such a release upon man
A Study of the Effects of Hydrostatic Pressure on Macromolecular Synthesis in Escherichia coli
In cultures of Escherichia coli 15 (thymine-, leucine-) which were incubated at high hydrostatic pressures, cell division occurred only at pressures below 430 atm but in a somewhat synchronous fashion at around 250 atm. The rate of leucine-14C incorporation into a macromolecular fraction of the cells diminished to a zero value at about 580 atm and that of uracil-14C incorporation to a zero value at about 770 atm. The rate of thymine-14C incorporation at pressures around 330 atm was that to be expected with a culture in which DNA synthesis is somewhat synchronous. At pressures above 500 atm, thymine-14C was incorporated only over the initial part of the pressure incubation and further incorporation under pressure was not observed no matter how long the duration of the incubation. We present evidence along several lines that the thymine incorporation kinetics reflect an effect of pressure on a locus at the origin (or termination) of a replication of the bacterial chromosome. The recovery of cell division and of the incorporation rates upon release of pressure were found to depend on the magnitude of the pressure and the duration of the pressure incubation
A Study of the Effects of Hydrostatic Pressure on Macromolecular Synthesis in Escherichia coli
Determination of the pressure-volume-temperature (PVT) surface of Isopar-M: a quatitative evaluation of its use to float deep-sea instruments
Deep Ocean Visualization Experimenter (DOVE): low-cost 10 km camera and instrument platform
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Environmental studies data base: development and data synthesis activities of the US Subseabed Disposal Program
The US Subseabed Disposal Program is assessing the scientific feasibility of subseabed emplacement of high-level nuclear wastes. Studies of disposal methods and of the barriers to radionuclide migration (canister, waste form and sediment) suggest that environmental information will be needed to address the impact of accidental release of radionuclides in the deep sea. Biological, physical, and geochemical data are being collected from field and laboratory studies as well as from literature searches. These data are being analyzed using a multicompartmental radionuclide transport model and appropriate physical oceanographic models. The data integrated into this framework will help answer two questions: what are the environmental effects of radionuclides which may be released in the deep sea, and what are the effects of such a release upon man
Biological studies of the US Subseabed Disposal Program
The Subseabed Disposal Program (SDP) of the US is assessing the feasibility of emplacing high level radioactive wastes (HLW) within deep-sea sediments and is developing the means for assessing the feasibility of the disposal practices of other nations. This paper discusses the role and status of biological research in the SDP. Studies of the disposal methods and of the conceived barriers (canister, waste form and sediment) suggest that biological knowledge will be principally needed to address the impact of accidental releases of radionuclides. Current experimental work is focusing on the deep-sea ecosystem to determine: (1) the structure of benthic communities, including their microbial component; (2) the faunal composition of deep midwater nekton; (3) the biology of deep-sea amphipods; (4) benthic community metabolism; (5) the rates of bacterial processes; (6) the metabolism of deep-sea animals, and (7) the radiation sensitivity of deep-sea organisms. A multicompartment model is being developed to assess quantitatively the impact (on the environment and on man) of releases of radionuclides into the sea
Biological ramifications of the subseabed disposal of high-level nuclear waste
The primary goal of the US Subseabed Disposal Program (SDP) is to assess the technical and environmental feasibility of disposing of high-level nuclear waste in deep-sea sediments. The subseabed biology program is charged with assessing possible ecosystem effects of radionuclides as well as possible health effects to man from radionuclides which may be released in the deep sea and transported to the ocean surface. Current biological investigations are attempting to determine benthic community structure; benthic community metabolism; the biology of deep-sea mobile scavengers; the faunal composition of midwater nekton; rates of microbial processes; and the radiation sensitivity of deep-sea organisms. Existing models of the dispersal of radionuclides in the deep sea have not considered many of the possible biological mechanisms which may influence the movement of radionuclides. Therefore, a multi-compartment foodweb model is being developed which considers both biological and physical influences on radionuclide transport. This model will allow parametric studies to be made of the impact on the ocean environment and on man of potential releases of radionuclides
