Comprehension of eruptive histories is critical in understanding the evolution of magmatic systems at arc volcanoes and may supply evidence to the petrogenesis of intermediate and evolved magmas. Within the 300 ka eruptive history of Mount St. Helens, Washington, the Kalama Eruptive Period, 1479- ~1750 CE was bracketed by interludes...
In an attempt to understand the phase equilibria and petrogenesis of MORB anorthitic plagioclase, Cr-spinel commonly hosted within anorthitic plagioclase has been investigated petrographically and compositionally. Based on spinel-anorthite relationships from three samples of plagioclase ultra-phyric basalt (PUB; Southeast Indian Ridge, Axial Seamount and West Valley Segment, Juan de Fuca...
Explosively erupting volcanoes and megathrust earthquakes (Mw 8+ magnitude) occur at subduction zones and adjacent volcanic arcs. Volcanic eruptions are observed occurring close in time to megathrust earthquakes in the historical record from at least the 18th century CE to present in locations globally, including Japan in 1707 CE (Chesley...
Studies reveal differences in slip segmentation and plate coupling along the Cascadia subduction zone. The segment between 44.0°N and 45.0°N exhibited reduced slip in the 1700 megathrust earthquake (Wang et al., 2013) and corresponds with previous rupture boundaries inferred from paleoseismic data (Leonard et al., 2010). Notably, this segment of...
The Pebble porphyry Cu-Au-Mo deposit in Alaska is one of the world's largest Cu-Au mineral resources. Late Cretaceous magmatic evolution in the Pebble district culminated with the intrusion of the Kaskanak Batholith and associated porphyry copper-gold-molybdenum mineralization. The Kaskanak Batholith is a multiphase granodiorite intrusion with an estimated footprint of...
This work explores the mechanical properties of single-phase niobium alloy C103 from room temperature to 600°C for the purpose of expanding safe uses of the material into new applications. The study utilizes a symmetrically notched triaxial tensile specimens to manipulate the internal stress field in order to observe the changes...
Several different petrological techniques have been applied to lava flows between
200 to 475,000 years old from Mount Hood, Oregon. Mount Hood is unusual, in comparison to nearby Mount St. Helens and Mount Jefferson, in that it has produced relatively homogeneous lava compositions over 475,000 years. Erupted lavas are mostly...
The ternary system (Bi₀.₅Na₀.₅)TiO₃-(Bi₀.₅K₀.₅)TiO₃-Bi(Mg₀.₅Ti₀.₅)O₃ (BNT-BKT-BMgT) was explored along the [75-(x 2) ]Bi₀.₅Na₀.₅TiO₃ - [25-(x 2)]Bi₀.₅K₀.₅TiO₃ - [x]Bi(Mg₀.₅Ti₀.₅)O₃ composition line. Thin films were fabricated using chelated mixing route solutions spin cast onto platinized silicon substrates. Processing parameters such as: excess cation molar%, solution molality, and crystallization temperatures, for composition where x=0,...
Heavily acceptor doped Pb1.02Dx(Zr0.5Ti0.5)1-xO3 ceramics, where A is the dopant, were investigated in this research. Dopants studied included iron, magnesium and manganese at mole concentrations x ≤ 0.20. X-ray diffraction data along with scanning electron microscopy images revealed the solubility limits of these ceramics. All doped compositions exhibited a shift...
Powder injection molding (PIM) is widely used to manufacture complex-shaped ceramic and metal components in high production volumes. In order to design and fabricate PIM components, it is important to know a number of material properties at different powder- polymer compositions. In this thesis, several predictive models for estimating rheological,...
The pressure history of a continental magmatic system can be deciphered by analyzing the composition of amphiboles in the eruptive products where the pressure of equilibration correlates with the depth of the magmatic system. This can reveal vertical evolution of the magma as amphibole composition varies significantly with temperature and...
In this study, 3D finite difference and 2D finite element forward modeling were used to create an electromagnetic sensitivity analysis for the Cotopaxi volcano in Ecuador. Magnetotellurics (MT) is a natural-source electromagnetic geophysical technique that images electrical conductivity. Measuring strong contrasts in electrical conductivity in volcanic materials allows for the...
Mount Sinabung, Sumatra, Indonesia initiated eruptive activity in 2010 with the addition of a magmatic component in 2013, after a 3 year period of quiescence. Observations of magmatic activity began with phreatomagmatic eruption starting July 2013 closely followed by extrusion of andesitic lava in December 2013. Lava effusion has persisted...
Volcanic and sedimentary deposits of the Mount Jefferson area (MJA) record a fourmillion-year history of arc-related volcanism related to the subduction of the Juan de Fuca plate beneath North America. 171 mapped stratigraphic units over an area of 150 km² reveal four periods of volcanic activity resulting in diverse composition...
Phase change memory materials are a set of chalcogenide or pnictogenide materials systems currently being researched for use in optical and resistive based memory systems due to their large change in optoelectronic properties between the amorphous and the crystalline states. For these materials systems to be considered as a suitable...
The corrosion behaviors of carbon and stainless steels were investigated in supercritical CO₂ (sCO₂ ) containing H₂O and O₂ simulating conditions that exist in direct sCO₂ power cycle heat exchangers. Thermodynamic properties of CO₂-H₂O-O₂ systems related to the corrosion phenomena were determined using NIST software. The exposure tests of the...
This dissertation is divided into two major chapters. The first chapter covers the geologyof the Encuentro deposit with emphasis in the intrusion sequence, vein mineral assemblages and distribution, and age of mineralization. The data used for this section includes field mapping, petrography, elemental analysis of biotite, and isotopic geochronology. The...
Conservation conflicts may develop on restoration sites with multiple species recovery objectives. For example, on Pacific Northwest prairies, the co-planting of the diploid cytotype of the common native wildflower Castilleja hispida with the endangered wildflower C. levisecta has resulted in putative Castilleja hybrids on restoration sites, prompting fears that genetic...
U.S. foreign policy during the period between World War II and the Vietnam War has been described as part of a “nation-‐building” or “liberal” grand strategy. This thesis contends that understanding U.S. efforts to influence the internal affairs of sovereign states through the spread of liberal values and institutions during...
Crystal-rich (40-50 vol.%) intermediate lava has been the primary eruptive product of several recent hazardous eruptions: Mt. Pinatubo, Philippines (1991), Soufriere Hills, Montserrat (1995-present), and Unzen, Japan (1990-1995). Despite this association with such devastating eruptions, the formation, timing, and evacuation of such magma is not well understood: do such eruptions...
This essay is an exploration of identity formation and expression. Humanity's identity formations create the orientations and languages with which we use to create our knowledge and understanding of the surrounding external environment (both social and physical) and our internal environment (psychological). This essay traces the sources of identity formation...
Directed energy deposition and laser cladding technologies are suitable advanced manufacturing techniques for applying corrosion-resistant claddings to large carbon steel components. In this work, we clad 309L stainless steel wire onto carbon steel substrates and examine the effects of cladding parameters (laser power and travel speed) on metallurgical bonding, composition,...
Pb(Zr,Ti)O₃ (PZT) is a very attractive material for use in piezoelectric-based microelectromechanical systems (MEMS) due to its high piezoelectric coefficients and ability for large displacements with relatively low applied fields (as compared to electrostatic-based MEMS). The piezoelectric effect is strongly anisotropic, thus it is very desirable to control the crystallographic...
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Brady J. Gibbons
Abstract:
Pb(Zr,Ti)O3 (PZT) is a very attractive material for use in
The purpose of this study is to illuminate the role,
the function, and the ironic outcome of the Victory in
Vietnam Committee's campaign pamphlet to recall Senator
Frank Church of Idaho in 1967. The VVC's political
strategy was to build credibility with the media through
the recall pamphlet. The analysis...
This thesis seeks to explain how Lord George Gordon
Byron achieves catharsis through the writing of his truth
in Don Juan. In the poem the narrator expresses Byron's
innermost emotion while at the same time the protagonist,
Juan, relates to readers on a more conscious level. The
ability that Byron...
The present research sought to investigate the relationship between an individual's word choice and their social well-being. In the present investigation, social well-being is a person's social health in relation to their social environment, social network, and ability to interact with others in a social context. This thesis was based...
A study was conducted to determine the quantity and distribution
of bark debris resulting from log rafting. Three distinct problems were
studied: (I) the quantity of bark dislodged from the logs while being
placed in the rivers and during transport in log rafts; (2) the percentage
of the bark that...
H₂-uptake positive strains (122 DES and SR) and H₂-uptake negative strains SR2 and SR3 of Rhizobium japonicum were examined for ribulosebisphosphate (RuBP) carboxylase and H₂-uptake activities during growth conditions which induced formation of the hydrogenase system. The rate of ¹⁴CO₂ uptake by hydrogenase-induced cells was about six times greater in...
Three types of experiments were designed to further characterize
the tryptophan decarboxylating enzyme of Reed and Crecelius
(1967).
1) Light inhibition studies were made with etiolated pea seedlings
to determine the in vitro response of the tryptophan decarboxylating
enzyme. Assays of indoleacetic acid oxidase (IAA oxidase)
and guaiacol-active pea seedling...
The present study was undertaken to determine, by measurement
of nuclear DNA, the degrees and frequencies of ploidy in the
last larval instar of the moth Galleria mellonella Linnaeus. While
such data have been amassed for a wide variety of vertebrate tissues,
few studies have been concerned with invertebrates and...
Fungi play critical roles in ecosystem processes and interact with plant communities in mutualistic, pathogenic, and commensal ways. Fungal communities are thought to be influenced by both associated tree communities and soil properties. However, the relative importance of the biotic and abiotic drivers of soil fungal community structure and diversity...
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Frank Andrew Jones
Fungi play critical roles in ecosystem processes and interact with
A large portion of farm accidents involves tractors. The study assumes that safety education is one method of decreasing the accident rate. The problem facing educators involves fragmentation of safety information and insufficient understanding of motivation as influenced by factors such as emotions and attitudes. The majority of literature most...
The purpose of this thesis is to aid in qualitative improvements to technical support documents on the Internet. By using a generic criticism this analysis will make substantive suggestions towards the improvement of this type of document by engaging the rhetoric employed by their authors. It will discuss the history...
My thesis is comprised of two articles, titled "Journeying Through (An)Other World: Examining the Role of Magic and Transformational Otherness in Sir Gawain and the Green Knight" and "Magic, Muggles, and Mudbloods: Examining Magical Otherness in J.K. Rowling's Harry Potter Series." The introduction frames the thematic, theoretical, and critical connections...
The Willamette Mission archeological project
consists of a broad program of cultural research in the
fields of archeology, history, and architecture. The
study focuses on the first Methodist mission in the
Pacific Northwest. Archeological excavations were
conducted in 1980 to locate the site of the mission, to
assess the site's...
The Willamette Mission archeological project
consists of a broad program of cultural research in the
fields of archeology, history, and architecture. The
study focuses on the first Methodist mission in the
Pacific Northwest. Archeological excavations were
conducted in 1980 to locate the site of the mission, to
assess the site's...
In Artemia salina nauplii acclimated in 0.25 M, 0.5 M, 1.0 M, 1.5 M,
2.0 M, and 2.5 M NaCl incorporation of ¹⁴CO₂ into free amino acids was
greatly stimulated in the higher salinities. The ¹⁴C label was found in
aspartic acid, serine, glutamic acid, proline and alanine.
Hypersalinity also...
This study was made to present any evidence as to differences
in the frequency of occurrence of corticolous lichens from east to
west in the Willamette Valley on a bark substrate of Quercus Garryana.
Twenty-four species of lichens were observed to be present
within the grid area of the 100...
To determine whether a homologous neurohormone, arginine
vasotocin (AVT), can elevate the occurrence of clasping behavior in
male rough-skinned newts (Taricha granulosa), intact, sexually inactive
males were injected with either AVT or saline. The incidence
of courtship was elevated in the group of males injected with AVT,
but not in...
Characterization of the enzymatic activity of the ionocyte
(mitochondria-rich cell) in the gill epithelium of Oncorhynchus
tshawytscha was explored.
1. A method for estimating the enzymatic activity per cell for
tissues is described.
2. The DNA content per cell for nucleated erythrocytes (O. tshawytscha) was determined to be 9.47 x...
A study on the cellular differentiation of the gill structure in
juvenile coho salmon (O. kisutch) with emphasis on the excretion of
monovalent ions was performed upon animals maintained under both
seawater and freshwater environments.
1. The excretion rate of sodium-24 was observed to be higher
for animals adapted to...
Many species of the Fagaceae have been variously interpreted
on the basis, primarily of external morphological characteristics.
The objectives of this study are to elucidate generic and specific
characteristics of the wood of Fagaceae and to attempt to obtain evidence
regarding taxonomic relationships among some of the species
occurring in...
Four species of euryhaline teleosts (chinook salmon, Oncorhynchus
tshawytscha, Walbaum; staghorn sculpin, Leptocottus armatus,
Girard; starry flounder, Platichthys stellatus, Pallas; shiner perch
Cymatogaster aggregata, Gibbons) were exposed to x-rays. The irradiated
animals were maintained in either of two different environments.
The effects of x-radiation were determined by observing the
percent...
The treatability of waters from four log ponds in Oregon by
physical and chemical treatment methods
was investigated.
Treatment processes included sand filtration, activated carbon contact and
coagulation with aluminum sulfate.
Preliminary studies were made at each log pond to determine
the homogeneity of the pond water for sampling
purposes...
A study was conducted to determine the oxygen uptake rate of
resuspended estuarine bottom sediments and the biodegradability of
the organic matter released during resuspension.
Oxygen uptake was measured on a Gilson Differential Respirometer
and the percent biodegradability was calculated by determining
the soluble organic carbon on a Beckman Carbonaceous...
Mitotic activity in the vascular cambium was determined from
ten samples from a single internode in each of four Douglas-fir
[(Pseudotsuga menziesii (Franco.) Mirb.)]trees. Counts of interphase and mitotic nuclei from nine cores in each sample piece
were averaged and expressed as the frequency and mitotic index.
The sampling error...
The main objectives of the current study were to obtain the complete cDNA sequence of an opioid-like receptor from an amphibian, the roughskin newt, Taricha granulosa, and investigate the receptor's tissue distribution and regulation following chronic exposure to the glucocorticoid corticosterone (CORT). Degenerate primers designed in highly conserved regions of...
The endocrine mechanisms involved in the initiation of sperm release
from the vertebrate testis have not been elucidated. A seasonally
breeding anuran amphibian, Hyla regilla, was selected as a model for
testing the hypothesis that steroid action is involved in gonadotropin-stimulated
sperm release. Experiments were carried out in vivo and...
In the wild, when an animal is exposed to predators or harsh conditions, the stress
response is often associated with fleeing behaviors, which are seen as increased
locomotor behavior. Handling-stress procedures and intracerebroventricular (icy)
injection of corticotropin-releasing factor (CRF) have both been shown to cause an
increase in locomotor activity...
During a 13-month period starting in October of 1976, adult
male rough-skinned newts (Taricha granulosa) were collected periodically
to study seasonal changes in reproductive status. Plasma
androgen concentration, measured by radioimmunoassay, is elevated
during autumn and spring (about 50 ng/ml). Winter and summer levels
are considerably lower (less than 10...
To determine whether meiotic maturation of ovarian follicles,
ovulation, and oviposition are influenced by male mating behaviors,
female rough-skinned newts (Taricha granulosa) were captured prior
to contact with males and maintained in simulated pond conditions.
Females were either exposed to male courtship and inseminated or
were isolated from male contact....
To quantify the reproductive behavior of male and female gray-tailed
voles, Microtus canicaudus, under conditions of natural
estrus, sexually experienced pairs were observed in a standardized
behavior test for 10 hours. The total duration of sexual
interactions averaged 223 minutes, which is considerably longer than
previously published reports on microtines....
The gonadal steroids, testosterone and estradiol, are known to be important
modulators of neuronal functions and behaviors in most vertebrate species. These
steroid hormones also elicit changes in neuropeptide synthesis and secretion, alter
specific neurohormone receptor levels, and alter neuronal morphology and
electrophysiology. Many of the actions of androgens and...
The North Atlantic zone of Costa Rica is an alluvial plain, whose fairly good soils and warm, extremely wet climate generate serious weed problems in cultivated crops and pastureland. Basic foods - corn, beans, rice and yuca - are important small farm crops. New land is still being opened for...
A 1.5 ha mixed conifer stand in the Blue Mountains of Oregon
was intensively examined to assess the impact of logging disturbance
on soils and herbaceous vegetation. Sampling was conducted six
years after much of the timber overstory was removed in a
shelterwood cut and yarded by crawler tractor. A...
Agricultural tile drainage is one of the major causes of increasing nitrate (NO3-) concentrations in surface water bodies thanks to the usage of nitrogen fertilizers and manure. Denitrifying bioreactors are constructed at the edge of agricultural lands in order to remove NO3- from drainage water through labile carbon substrates intended...
Many initially healthy Pelargonium seedlings developed symptoms
of Verticillium wilt in an Oregon State University greenhouse
when they attained blooming age. The symptoms first appeared in
May as "edge burning," yellowing, and wilting of leaves. In late
summer, these seedlings which were the offspring of Verticillium
infected plants, became severely...
Dipterans of the family Ephydridae (shore and brine flies) are well
known for their ability to tolerate and thrive in a wide variety of
physically harsh circumstances. The immature stages of one such species
of this family, Ephydra hians, are characteristically limited in
distribution as benthic inhabitants of highly alkaline...
A computerized ranch simulation model of an eastern Oregon cattle
ranch was tested for its ability to evaluate the economics of public
rangeland improvement practices. The model was used to estimate
likely impacts of various public policy alternatives for rangeland
improvement on the relative profitability of a 400 mother cow...
A farm level comparative study was conducted to
determine the extend to which the production component of
the tomato industry of Panama is competitive with its
American producer counterparts in California. In addition,
processing costs, and marketing conditions/costs are factors
that determine a competitive potential. The objective of
this study...
Shewanella oneidensis MR-1 is a gram-negative, facultative anaerobic bacteria with the capability of dissimilatory metal reduction. The ability of the organism to reduce a wide range of solid metal-oxides during anaerobic respiration makes it an ideal candidate for the powering of microbial fuel cells (MFCs), which capture the electrons discharged...
A study was conducted to determine the quantity and character
of substances leached from logs floating in water, and the rate of
leaching of these substances. The species of wood studied were Douglas
fir and ponderosa pine. The research was carried out in a controlled
laboratory environment with log sections...
A series of log storage experiments were conducted to determine
whether leachates derived from water storage of logs are acutely
toxic to fish. Log segments approximately 18 inches long and 16 inches
in diameter were stored in tanks and held submerged for a period of
7 days. The holding water...
Tissue differentiation of the primary root and its associated
laterals is reported. Secretory elements are the first of the primary
tissues to mature. They appear to be located between the precursory
phloem and pericycle in the primary root, but are more closely
associated with the pericycle in long lateral roots....
Intracellular signaling cascades can no longer be viewed as linear pathways that relay and amplify information. Often, components of different pathways interact, resulting in signaling networks. The interactions of different pathways and the dynamic modulation of the activities of the components within signaling pathways can create a multitude of biological...
The coagulation of effluent from the kraft pulping and
papermaking process was investigated. The amount of material
coagulated from saline mixtures of the effluent is determined
as a function of time, salinity, kraft effluent
concentration, and mixture pH. Individual sources of salinity
include sea water and several different solutions of...
Agricultural production in the Sahelian region of Africa is
among the lowest in the world. Cyclical infestations of locusts and
grasshoppers have contributed to this low productivity. The infestations
appear to be triggered by heavy rainfall at the beginning of a crop season
after extended drought. Because locusts and grasshoppers...