In the past decade, declines in amphibian populations have captured scientific and popular interest. The causes of the declines are likely to be complex and involve interactions between several environmental stressors. Using multifactorial experiments, I investigated the combined effects of several anthropogenic stressors on developing amphibians in Oregon, USA. In...
A survey of the major bodies of water, temporary and perennial,
in the region of Northern Utah revealed a limited distribution of
the Notostraca. Lepidurus (Linn.), the only representative
found, was restricted to a single temporary shallow lake. Dry Lake,
in the southern end of Cache County.
Dry Lake occupies...
The research presented in this dissertation focuses on the model generation and modeling processes of student teams that participate in capstone, undergraduate engineering physical and virtual laboratory projects. The Heat Exchange Laboratory Project, the Ion Exchange Laboratory Project, and the Virtual Chemical Vapor Deposition (CVD) Laboratory Project provide the context...
Time-course growth chamber studies were conducted on little mallow
(Malva parviflora L.) to determine whether sublethal doses of lactofen
(1'-(carboethoxy)ethyl-5-[2-chloro-4-(trifluoromethyl) phenoxy]-2-
nitrobenzoate) would enhance uptake of glyphosate (N'-(phosphonomethyl)
glycine) by altering membrane permeability. Lactofen-induced membrane
peroxidation was determined by harvesting leaf discs, measuring stress
ethylene evolution, and recording increases in...
The purpose of this study was to determine if a significant
difference in cognitive achievement and retention occurred when skeletal
system anatomy and terminology were presented utilizing either videotaped
presentations or a traditional laboratory procedure.
Fifty-three first semester nursing students enrolled in biology
(Bio. 160 anatomy and physiology) at Lethbridge...
Peroxiredoxins (Prxs) are dominant peroxide-reducing enzymes with two important roles: they protect all organisms from oxidative damage induced by peroxides, and in eukaryotes, they participate in hydrogen peroxide signaling pathways. This dissertation presents studies aimed at the biophysical characterization of select Prxs and a Prx reductase to elucidate their structure-function...
Feeding of [3-¹³C, 2-¹⁵N]arginine, 38a, unequivocally established that the β-
arginine moiety of blasticidin S, 1, was formed from α-arginine by an intramolecular
migration of the α-amino group to the β- position. Further feedings using chirally
deuteriated arginines 38e and 38f revealed that the aminomutase process occurred with
inversion of...
Identifying appropriate units for conservation requires knowledge of evolutionary
patterns and risks of managing at different geographical and genetic scales. I examined
genetic diversity at different geographical scales among 11,400 rainbow trout
(Oncorhynchus mykiss) from 243 locations in 13 major river basins throughout much of
their range and among coho...
Twenty-six Holstein and 18 Jersey multiparous cows in a randomized block design were assigned by calving date and breed to a non-anionic prepartum diet (CTRL) or a treatment diet containing a commercial anionic salt supplement (Animate®). Control and treatment diets were formulated to a dietary anion-cation difference (DCAD) of 21.3...