An ecological study of a microorganism similar to that isolated
in 1956 and designated as Micrococcus radiodurans indicated
that the organism could be isolated from several different environments.
By taking advantage of its radio-resistivity, high levels of
gamma radiation were used in the isolation procedures to inactivate
most of the...
This study examined the effects of Roundup
[N-(phosphonomethyl) glycine] and N-Serve [2-chloro-6-
(trichloromethyl) pyridine] on nitrifying organisms in
static batch, perfusion soil columns, and a new continuous-flow
soil column system. The continuous-flow method is new
to nitrification studies and was shown to produce greater
nitrifier activity than either static batch...
There has been increased concern about radiation dose to the female breasts, with approximately 200,000 new breast cancers being diagnosed each year in the United States. The unprecedented increase in the use of radiologic exams on younger women has also raised some additional concerns about how procedures are performed. The...
This gamma irradiation study was conducted to establish an LD50 of the hop (Humulus lupulus L.) cultivar Cascade . The overall, long term goal is to generate replacement hop cultivars by inducing minor but significant DNA alterations with gamma radiation to improve agronomic quality without changing the brewing profile. The...
An estuary, unlike the open ocean, is a dynamic system that is continuously
undergoing changes in its physical and chemical properties. Marked fluctuations
in the levels and kinds of nutrients, temperature, and salinity are normally found
in estuarine environments. These changes occur principally as a result of freshwater
My thesis explored the effects of and potential mediating mechanisms for an important environmental stressor, ultraviolet-B (UVB) radiation. UVB radiation has negative effects on organisms in both terrestrial and aquatic systems. I used meta-analysis to quantify the effects of UVB radiation on a diversity of aquatic organisms (Chapter 2). UVB...
Iodoacetic acid and diphenylamine were used in this study to
elucidate the mechanisms of resistance of Micrococcus radiodurans
to radiation. This organism, a gram positive, non-spore forming,
salmon-pink, tetracoccus has a LD₅₀ of 213,000 R when grown in
the absence of radio-modifying agents.
M. radiodurans, when grown in media containing...
Quantity variations in pigments and lipid classes were determined
following γ-irradiation of Micrococcus radiodurans, Sarcina
lutea, and Pseudomonas aeruginosa.
Pigmentation was determined by extraction with organic solvents
and measured as optical density at 475 mμ for M. radiodurans
and S. lutea, and 410 mμ for Ps. E aetuginosa. Pigments of...
Spacecrafts experience radiation in the course of their operation
and all electronic equipment on board these spacecrafts has to
be designed to withstand the effects of this radiation.
This thesis describes the effects of total ionization dose (TID)
and single event transients (SET) in phase-locked loops - an