The electrode size dependence of the effective large signal piezoelectric response coefficient (d(33,f)) of lead zirconate titanate (PZT) thin films is investigated by using double beam laser interferometer measurements and finite element modeling. The experimentally observed electrode size dependence is shown to arise from a contribution from the substrate. The...
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and related compounds are well-recognized for their immunosuppressive activity, which is mediated through an intracellular receptor and transcription factor, aryl hydrocarbon receptor (AhR). Laboratory animals exposed to TCDD are less resistant to infection and have severely impaired humoral and cell-mediated immune responses. This dissertation addressed the hypothesis that...
Index counts for the Pacific Coast race of the band-tailed pigeon (Columba fasciata monilis) have declined by -2% per year since survey efforts began in the 1950's and 60's. Mineral sites, important resources with high ion concentrations, are regularly visited by band-tailed pigeons which nest in surrounding forest lands. I...
Proper immune function is indispensable, as failure to mount an immune response against a pathogen can lead to serious complications or even death. T cells act by enhancing the activation of phagocytic cells as well as the activation of B cells. Their widespread influence on an immune response makes optimal...
The effect of competition on the brood survival of the Douglas fir
beetle Dendroctonus pseudotsugae Hopkins, in down or windthrown
Douglas-fir Pseudotsuga menziesii (Mirb.) Franco was studied in the
field and the laboratory. The investigation of the role of competition
in the population dynamics of the beetle had four objectives:...
Fire suppression in high-elevation sagebrush steppe over the last century has
profoundly influenced the structure and complexity of vegetation communities.
Although fire is the primary management tool used to restore these areas, the impact
of this management practice on associated avian communities is poorly understood.
We examined patterns of habitat...
Pygmy rabbits (Brachylagus idahoensis) in Oregon and Washington are a sagebrush (Artemisia tridentata spp.) obligate species of concern because of declining populations and extirpation from much of their range. Efforts are underway to establish a captive bred population of the Columbia Basin pygmy rabbit in Washington state for reintroduction into...
Thirty-six Suffolk ewes were randomly divided into two equal
groups. One group received a selenium (Se) deficient diet, while the
other diet contained sodium selenite at a level of 0.2 ppm Se in the
total diet. All ewes were sampled for plasma glutathione peroxidase
(GPx) and whole blood Se at...