Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko),
is a widely distributed species in western north America,
and a major economic pest of wheat (Triticum aestivum L.)
and barley (Hordeum vulgare L.). The objectives of this
study were to : 1) determine the inheritance of seedling and
adult plant resistances in...
Cold hardiness and phenology are important adaptive
traits for perennial plant species in temperate climates.
Timing of growth, dormancy, and associated cold acclimation
and deacclimation represents a delicate balance between
maximizing growth under favorable conditions and minimizing
frost damage under unfavorable conditions. Geographic
patterns of genetic variation in adaptive traits,...
Changes in the type and amount of plant inputs can occur gradually, as with succession, or rapidly, as with harvesting or wildfire. With global change it is anticipated that both gradual and immediate scenarios will occur at increasing frequency. Changes in vegetation inputs alter the quality and quantity of soil...
The purpose of this paper is to illustrate the use of Linear Programming (LP) and
other mathematical procedures to evaluate watershed and perpetuity constraints on forest
land use for a selected scenario in Terengganu, Peninsular Malaysia. The paper describes
the system of modelling and forecasting estimates of potential timber growth,...
Landslides are a natural hazard that have major societal, economic, and
environmental impacts. The understanding of landslides begins with the observation that
they are a spatial problem. Spatial relationships have historically been explored with
maps, and landslides are no different. Such maps range in focus from inventory maps,
which identify...
To understand the processes that lead to the formation of the oceanic crust, one must know the composition and the depth at which primary melts originate. Towards this end, this dissertation focuses on plagioclase-hosted melt inclusions from plagioclase ultraphyric basalts (PUBs). Plagioclase is usually considered to be the second phase,...
The theoretical analysis of an unseeded, isothermal mixed-suspension
mixed-product-removal (MSMPR) crystallizer with a fines trap is developed.
The lumped parameter system equations are presented for a homogeneous
nucleation and a number-dependent secondary-nucleation model. Linear
stability analysis and system simulations are used to investigate the
system's dynamic behavior.
Modal control algorithms...
Understanding continental crust formation and modification is a fundamental and longstanding geologic problem. Influx of mantle-derived basaltic magma and partial melting of the crust are two ways to drive crustal differentiation. This process results in a low density upper crust and denser, more refractory lower crust, creating significant and vastly...
Seed moisture is a primary factor influencing seed quality during harvesting, storage, and marketing of grass seed. However, the Association of Official Seed Analysts' Rules for Testing Seeds do not contain methods for moisture testing. The oven methods in use by seed testing laboratories in the U.S. are diverse and...
Nanoparticles have become more prevalent from their use in sunscreen to antimicrobial agents in socks. In light of these applications, gaining a fundamental understanding of how NPs interact with humans is crucial for their future. Specifically, how cells interact with NPs and what factors drive the modes of cellular uptake....
The over-arching theme of this work is that soil data affect the performance and realism of vegetation models with particular focus on their ability to predict or explain disturbances such as fire or disease. We tested the sensitivity of the Excel version of the 3-PG model to soil properties and...
Current research indicates that the expansion of
western juniper can inhibit soil water retention, storage
and prolonged releases from watersheds. This phenomenon
is of great importance in eastern Oregon, as western
juniper is encroaching into sagebrush/grass communities
with a correlated reduction in herbaceous ground cover,
resulting in reduced infiltration rates...
The main objective of this study was to estimate the demand for and net economic benefits from Oregon salmon sport fishing. The travel cost method was used as the primary technique for demand analysis. Several empirical estimates of consumer surplus per trip and per fish were obtained from different estimation...
The adsorption equilibrium and kinetic behavior exhibited
by β-lactoglobulin at silanized silicon surfaces of varying
hydrophobicity were examined using ellipsometry. Adsorption
equilibrium results were used to construct adsorption
isotherms; the adsorbed mass of β-lactoglobulin was observed
to increase with increasing surface hydrophobicity, within a
defined range of hydrophobicity. Adsorption kinetics...
Effects of gastrointestinal transit on plasma concentrations of drugs from enteric-coated pellet formulations were demonstrated using pharmacokinetic models describing plasma concentrations of drugs from various enteric-coated pellet formulations. Gastric emptying time, lag time of emptying, and drug release rate from pellets in the small intestine, along with other pharmacokinetic parameters...
Mobile and telecommunication industry has experienced tremendous growth in the recent past. Miniaturization and increased functionality have become necessary for all passive components in the system. Bandpass filters are critical passive components in any communication system and the existing designs in the crucial 1-10 GHz bandwidth suffer many drawbacks. For...
The Caribbean Plateau is an oceanic large igneous province (CLIP). A widely accepted model for LIP petrogenesis proposes that these large bodies of igneous rock are formed by decompression melting associated with upwelling mantle plume heads during the initiation of hotspot activity. According to this classical model, petrogenesis occurs over...
This dissertation investigates the effect of endogenous and exogenous events on firm behavior and performance. These are fundamental questions in economics. The contribution of this study is threefold. First, it provides estimates of the impact of mergers on railroad efficiency, which has important antitrust implications. Second, it provides new estimates...
Inheritance from pre-existing mantle domains and fluid and melt contributions from active subduction together produce the geochemical signatures of mantle-derived arc basalts. In this context, this work evaluates the evolution of Cascadia mantle sources by documenting the isotopic and compositional characteristics of primitive basalts along a transect across the Eocene-Oligocene...
High intensity sampling was undertaken to characterize the temporal and spatial
variability of oxidized nitrogen (NO3-N + NO2-N), ammonia-nitrogen (NH3-N), total
dissolved phosphorus, total unfiltered phosphorus and orthophosphorus (PO4-P) from two
adjacent small streams in Western Oregon's Coast Range, Deer Creek (303 ha) and Flynn
Creek (203 ha). Deer Creek...
The purpose of this study was to determine the effect of population
size, type of ownership, number of hours open per week,
pharmacy location, type of pharmacy, average annual store sales
volume, average number of prescriptions filled per day, patient profile
system and delivery service on prescription price, dollar markup...
Field study with 5 tall fescue genotypes treated at the vegetative
growth stage, with 0, 0.28, 0.56, and 0.84 kg/ha of mefluidide
was initiated in July, 1980. The regrowth of these plants were again
treated at the booting growth stage in April, 1981, with the same
rates of mefluidide as...
This study explored the applicability of a small portion of Western
communication theory and practice to an Eastern culture. It compared
the opinions or professional judgments of five Thai speech instructors
who had obtained their doctorates in American universities with those of
five American speech instructors who hold doctorates in...
The tissue and substrate degradational enzymes, acid hydrolases,
in endosperm were studied in order to discern the mechanism of seed
shriveling in triticale (XTriticosecale Wittmack).
Acid hydrolases in crude extract of 7-week-old developing
endosperm of 2 lines each of triticale with shriveled (6TB,JZBS) and
plump seeds (6TA, RBP) were successfully...
The success of a plant breeding program depends upon the availability of
useable genetic diversity. Such diversity may be enhanced depending on the type of
hybridization strategy employed. Segregating progenies resulting from F2
populations, a double cross, and a top cross were compared for the amount of
useable genetic diversity...
Research was conducted near the Starkey Experimental Forest and Range in
northeastern Oregon. Effects of defoliating bluebunch wheatgrass (Agropyron
spicatum (Pursh) Scribn. and Smith) to increase the quality of regrowth available on
elk (Cervus elaphus nelsoni) winter range were studied from 1988 through 1990.
Clipping treatments were implemented to condition...
Quantitative habitat models of wildlife-habitat relationships are developed to
formalize our current understanding about an ecological system. A habitat
association model is one of these models that is useful for answering questions
about how the habitat is occupied, how much growth habitat is required by the
animal, or how the...
Oral administration is the most practical way of vaccination of fish. It has advantages over intraperitoneal injection and immersion methods that include no stressful handling, no interference with routine fish husbandry and antigens can be delivered to the fish in their feed.
An oral antigen delivery system was developed for...
The hypotheses of this research were (1) to test if
the antagonistic effect of ethanol on liver copper could
be seen within a short period when ethanol ingestion,
low dietary copper and high metabolic demand represented
by either pregnancy plus lactation or rapid growth are
simultaneously present and (2) to...
Despite the importance of tropical forest ecosystems in the global carbon cycle, there have been few studies of carbon dynamics in this biome. The magnitude of carbon stocks in the tropics and their changes over time are poorly known since ground-based observations are lacking. In this study, total carbon stocks...
The work presented in this dissertation highlights the various techniques available to characterize the increasingly complex surfaces of engineered biomaterials. The methods used range from the simple measurement of a contact angle with a smartphone to a complex synchrotron technique like near edge x-ray absorption fine structure (NEXAFS) spectroscopy to...
Feedlot finishing of beef cattle in Southern Alberta involves
income risk due to the variability of prices of feeders, feed and
finished cattle. Several strategies are available to reduce this
risk, including hedging of cattle on feed, participation in a Federal-
Provincial government and producer established income stabilization
program for...
Tansy ragwort (Senecio jacobaea L. ) is a poisonous weed which
infests alfalfa fields in western Oregon. Studies were conducted to
evaluate the effectiveness of asulam (methyl sulfanilylcarbamate)for
control of tansy ragwort in alfalfa and to elucidate factors responsible
for its selectivity. In seven replicated field trials in 1973 and...
My objectives were to: 1) develop a point count technique for estimating relative
abundance of band-tailed pigeons (Columbafasciata monilis), 2) determine the
availability, distribution, and interspersion of mineral sites, and nesting and foraging cover in relation to abundance of band-tailed pigeons in west-central Oregon, and 3) test the hypothesis that...
Prior to eruption at mid-ocean ridges, melts must travel through >6 km of crust from their origin in the mantle. The final composition of the melts is dependent on both the melting conditions and magmatic processes within the crust. While mid-ocean ridge basalt (MORB) glasses are commonly used to infer...
The travel cost method of deriving demand and value of recreation
does not include fixed costs of recreational durable goods purchases
or allow for supply restrictions on the number of suitable
sites available. The omission of these two real-world situations
results in derivation of demand curves which are more inelastic...
The adoption of modem agricultural technologies in Bangladesh increases
overall agricultural productivity and income primarily through the increase in cereal
crop production. It, however, impedes the productivity of several other minor crops
and fishes, widens the distribution of income between the rich and the poor, exploits
resources and obstructs the...
Chloroplast DNA (cpDNA) variability and phylogeny were
studied via analysis of restriction site mutations and DNA
sequencing in a complex of three closely related species of
pines: Pinus radiata D. Don, P. attenuata Lemm., and
muricata D. Don. Genomic DNA from 384 trees representing
20 populations in the complex were...
This dissertation used land rent theory and an economic model of land-use conversion to examine the main drivers of the deforestation occurred in Antioquia,Colombia, between 1980 and 2000. Land-cover information at a semi-fine scale (1:25,000)
obtained largely from aerial photography was employed to calculate deforestation. In addition, free international databases...
This dissertation is about the likelihood analysis of ordered categorical responses in a longitudinal/spatial study, meaning regression-like analysis when the response variable is categorical with ordered categories, and is measured repeatedly over time or space on the experimental or sampling units. Particular attention is given to the multivariate ordinal probit...
Investigation on barley genotype contribution to beer flavor is a relatively new area of research but has interest from members of the malting barley supply chain. This body of work builds upon previous studies by approaching it from new angles that further supports the malting and brewing industries’ interests around...
From July 1985 to April 1987 the pelagic zooplankton community of Crater Lake, Oregon was studied to determine taxonomic structure, absolute and relative densities, and spatial and temporal distributional patterns. Samples were collected using vertically-towed zooplankton nets. The community structure consisted of two cladoceran and nine rotifer species, which were...
Experiments were conducted to study the effect of pore size
distribution on the diffusion of 2, 4-Dichlorophenoxyacetic acid (carbon-
14) through water saturated porous media. Eight size fractions of
glass beads were used representing the porous media. It was found
that as the average particle radius, and hence pore radius,...
Purpose of the Study
The basic purpose of this study was to examine the attitudes and
opinions of community college personnel toward faculty involvement
in policy formulation.
Procedures
The statistical and subjective data for this study were obtained
from two major sources. (1) A statistical questionnaire was
developed to identify...
A survey of major bean (Phaseolus vulgaris) breeding programs and
seed producing areas in Idaho, Washington, and Oregon was conducted to
determine the occurrence of cucumber mosaic virus (CMV), recently reported
to be seedborne in beans. Some 259 plants, sampled from breeding
lines of diverse germplasm, were found by enzyme-linked...
Purpose: The basic purpose of this study was to evaluate theeffectiveness of paraprofessional workers trained to work as guidanceassistants to professional counselors in elementary and secondaryschools. The study included an identification of the appropriate roleof guidance assistants, counselors, and administrators in their relationshipwith one another in a team setting. Role...
The main objective of this research was to assess the
nutritional status of sheep and goats grazing two rangeland
types in Baluchistan, Pakistan. These types were Artemisia
maritima/Haloxylon griffithii association represented by the
Zarchi Field Station and Cymbopogon shoenanthus, found at
the Tomagh Field Station. Seasonal above ground biomass
production...
In order to produce infectious virus progeny, vaccinia virus (VV)
undergoes morphogenic proteolysis to regulate the structural rearrangements of
virus particles. Several of the major structural precursor proteins of VV are
cleaved at a conserved Ala-Gly-X (where X is any amino acid) motif by the VV
I7L core protein proteinase...