Index Catalog // ScholarsArchive@OSU

Magnetically assisted liquid-solid fluidization in a gradient magnetic field : Theory and application

Creator:: Sornchamni, Thana
Abstract:: Development of efficient methods for the destruction of solid wastes and recovery of valuable resources is needed to support long-duration manned missions in space. In particular, these technologies are required for deployment in hypogravity and microgravity environments, such as at the lunar or Martian surfaces. Gradient Magnetically Assisted Fluidized Bed...
Resource Type:: Dissertation

Analysis of hydrology and erosion in small, paired watersheds in a juniper-sagebrush area of central Oregon

Creator:: Fisher, Michael, (Michael Patrick), 1966-
Abstract:: 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...
Resource Type:: Dissertation

Solubility of aluminosilicates in kraft green and white liquors

Creator:: Wannenmacher, P. Nick
Abstract:: The increasing occurrence of aluminosilicate caused complications in krafi pulp mills can be attributed to the closing of purge points and the expanded use of contaminated feedstocks and recycled fiber sources. An active purge of aluminum and silicon from the chemical recovery cycle must be undertaken in order to maintain...
Resource Type:: Dissertation

Geographic variation in genetic and meristic characters of coastal cutthroat trout (Oncorhynchus clarki clarki)

Creator:: Williams, Thomas Herbert
Abstract:: Understanding how populations within a species interact across various geographic and temporal scales is fundamental to developing appropriate conservation strategies. I examined the geographic variation in genetic and meristic characters of coastal cutthroat trout (Oncorhynchus clarki clarki) based on approximately 1,400 fish sampled from 54 populations spanning their distributional range...
Resource Type:: Dissertation

A multi-case study of elementary classroom teachers' transitions to reform-based mathematics instruction

Creator:: White, Elizabeth Busch
Abstract:: The National Council of Teachers of Mathematics published their vision of active, problem-centered instruction with a goal of conceptual understanding in 1989. Fifteen years after these reforms were proposed the changes are reflected in school policy and elementary mathematics curriculum, but only limited change has actually occurred in classroom instruction....
Resource Type:: Dissertation

Determination of fluorinated alkyl substances in aqueous systems

Creator:: Schultz, Melissa M.
Abstract:: Fluorinated alkyl substances, which can be persistent, toxic, and bioaccumulative, have been quantitated in many densely populated and remote regions, including in air, surface waters, groundwater, and biota; however, little is known about their transport or behavior in the environment. Wastewater effluent is one of the principal routes for introducing...
Resource Type:: Dissertation

The language of mathematics : a functional definition and the development of an instrument of measure teacher perceived self-efficacy

Creator:: Gray, Virginia
Abstract:: Mathematics is permeated with language; it appears in the form of new words and some old words with new meanings. There are new symbols to be able to read and consume; much information is presented in tabular or graphic form, and finally the language in a mathematics class has its...
Resource Type:: Dissertation

A beta dosimeter and spectrometer utilizing plastic scintillators and a large-area avalanche photodiode

Creator:: Kriss, Aaron A.
Abstract:: The purpose of this research was to develop and test a radiation detector to perform beta dosimetry and spectroscopy. The detector utilizes plastic scintillator volumes to produce scintillation light in proportion to the amount of energy deposited in them, and a large-area avalanche photodiode to convert the light to electrical...
Resource Type:: Dissertation

An artificial neural network approach to laser-based direct part marking of data matrix symbols

Creator:: Jangsombatsiri, Witaya
Abstract:: Certain applications have recently appeared in industry where a traditional bar code printed on a label will not survive because the item to be tracked has to be exposed to harsh environments. Laser direct-part marking is a manufacturing process used to create permanent marks on a substrate that could help...
Resource Type:: Dissertation

Analysis of high-risk hispanic families in a family support program : characteristics, factors affecting parenting skills over time, and age-paced newsletter efficacy

Creator:: Weatherspoon, Joni
Abstract:: Two studies investigated the characteristics of high-risk Hispanic parents with young children who were enrolled in a primary prevention home visitation program targeting first birth families. In the first study, more and less acculturated high-risk Hispanic families were compared to high-risk non-Hispanic White families on differences in demographic characteristics, risk...
Resource Type:: Dissertation

The first year of teaching secondary agricultural education : a national study

Creator:: Warnick, Brian K.
Abstract:: The purpose of this study was to describe the perceptions of the first year experience of teaching secondary agriculture and to explore the relationships between these perceptions, the characteristics of beginning agriculture teachers, and the types of support provided to beginning teachers. An additional focus of the study was to...
Resource Type:: Dissertation

Perceptions of community hospital physicians on computerized physician order entry

Creator:: Churchill, Brian E.
Abstract:: Objectives: To identify the perceptions of community hospital physicians on computerized physician order entry. Design: Multi-method approach consisting of a mail survey of 659 community hospital physicians with active admitting privileges at three PeaceHealth, Inc., along with follow-up personal interviews with stratified random selection from completed survey. Measurements: Perceptions were...
Resource Type:: Dissertation

Studies on isoprenoid biosynthesis in Euglena gracilis

Creator:: Kim, Dojung
Abstract:: This dissertation describes studies of isoprenoid biosynthesis in the phytoflagellate Euglena gracilis. Elucidation of a novel isoprerioid pathway, the 2-Cmethyl-D-erythritol-4-phosphate (MEP) pathway, in addition to the generally known mevalonate (MVA) pathway, led to extensive exploration of the distribution of both pathways in a variety of organisms. To date, photosynthetic eukaryotes...
Resource Type:: Dissertation

Syntheses and evaluation of putative enzyme inhibitor of isoprenoid biosynthesis

Creator:: Phaosiri, Chanokporn
Abstract:: The discovery of the methylerythritol phosphate pathway (the MEP pathway) as an alternate pathway for isoprenoid biosynthesis in some organisms including most bacteria, malarial parasites and plants, but not in animals, has stimulated extensive studies in this area. Research has revealed the potential of finding novel antibacterials, antimalarial drugs, and...
Resource Type:: Dissertation

Individual and population responses to abiotic stresses in Italian ryegrass (Lolium multiflorum Lam.)

Creator:: Martinez-Ghersa, Maria Alejandra
Abstract:: Plant form is a compromise between resource gathering, reproduction and the tolerance to physical demands of the abiotic and biotic environment. In an agricultural field in addition to the natural factors causing stress, humans also introduce physical and mechanical stresses, and chemical pesticides into the environment. Many of these factors...
Resource Type:: Dissertation

Studies toward the total synthesis of phorboxazole A

Creator:: Kuntiyong, Punlop
Abstract:: Studies toward the total synthesis of a highly potent cytotoxic marine natural product, phorboxazole A, were conducted and resulted in a route to an advanced intermediate, C4-C32, for this purpose. A key feature of our approach is the stereoselective synthesis of two cis-2,6-disubstituted tetrahydropyrans present in the macrolide portion of...
Resource Type:: Dissertation

Three essays on nonparametric and semiparametric regression models

Creator:: Yao, Feng
Abstract:: This dissertation contains three essays on nonprametric and semiparametric regression mod- In the first essay, we propose an estimation procedure for value at risk (VaR) and expected shortfall (TailVaR.) for conditional distributions of a time series of returns on a financial asset. Our approach combines a local polynomial estimator of...
Resource Type:: Dissertation

Two new roles for the TYMV tRNA-like structure : translation enhancement and repression of minus strand synthesis

Creator:: Matsuda, Daiki
Abstract:: Some positive-strand RNA plant viruses possess a transfer RNA-like structure (TLS) at the 3'-terminus of their genomic RNAs. The closest mimicry to tRNA is exhibited by the valylatable TLSs from tymoviruses and furo-like viruses, which are able to interact with key cellular tRNA enzymes: [CTP, ATP]:tRNA nucleotidyltransferase (CCA NTase), valyl-tRNA...
Resource Type:: Dissertation

Inhibition of exercise-induced oxidative stress, inflammation and muscle damage by prior supplementation with the antioxidant vitamins E and C

Creator:: Mastaloudis, Angela
Abstract:: To determine if 6 weeks prior supplementation with vitamins E and C could alleviate exercise-induced DNA damage, prevent lipid peroxidation and inflammation, slow the rate of vitamin E utilization and/or attenuate muscle damage, 22 subjects (11 females: 11 males) were studied during a 50 km (32 mile) ultramarathon. Subjects were...
Resource Type:: Dissertation

A multi-product, multi-depot periodic distribution problem

Creator:: Parthanadee, Parthana
Abstract:: Physical distribution is one of the key functions in logistics systems, involving the flow of products from manufacturing plants or distribution centers through the network of transportation to consumers. The function is very costly, especially for the distribution industries. During the past decades, the significance of physical distribution has increased...
Resource Type:: Dissertation

Molecular characterization of criniviruses and ilarviruses infecting strawberry

Creator:: Tzanetakis, Ioannis E.
Abstract:: Pallidosis is a disease of strawberry identified in 1957 with an unknown etiology. Two previously uncharacterized viruses in strawberry, Strawberry pallidosis associated virus (SPaV) and Beet pseudo-yellows virus (BPYV), have been found associated with disease symptoms. The complete nucleotide sequence of both viruses was determined and molecular detection protocols developed....
Resource Type:: Dissertation

Antimicrobial contaminant removal by multi-stage drinking water filtration

Creator:: Rooklidge, Stephen J.
Abstract:: The fate of antimicrobials entering the aquatic environment is an increasing concern for researchers and regulators, and recent research has focused on antimicrobial contamination from point sources, such as wastewater treatment facility outfalls. The terraccumulation of antimicrobials and mobility in diffuse pollution pathways should not be overlooked as a contributor...
Resource Type:: Dissertation

New bioactive natural products from marine algae and cyanobacteria

Creator:: Sabry, Omar Mohamed
Abstract:: This thesis is an account of investigation on the natural products deriving from various marine algae and has resulted in the discovery of eleven novel bioactive metabolites. Isolation and characterization of these new molecules were carried out using different chromatographic techniques and by analyses of different spectroscopic data, respectively. Using...
Resource Type:: Dissertation

Recordando memoria : shaping Chicana identity

Creator:: Martinez, Yolanda Tellez
Abstract:: This research explored the self-concept of Chicanas in terms of their lived experiences and how those experiences influenced the shaping of their identity. It examined the multiple labels Chicanas use to self-identify and the context or situations in which they use specific labels. Moreover, it took into account the influence...
Resource Type:: Dissertation

Development and in vivo testing of novel hydrochlorothiazide gastric retention formulations in healthy volunteers and stage I hypertensive patients

Creator:: Farid, Samar Farghali
Abstract:: This thesis describes in vitro and in vivo evaluation of a gastric retention formulation (GRF) developed at Oregon State University. The formulation was prepared from xanthan gum and locust bean gum as gelling agents and other formulation ingredients were added, then it was originally vacuum oven dried. The effect of...
Resource Type:: Dissertation

Synthesis of furanoeremophilane sesquiterpenoids

Creator:: Shanmugham, Meenakshi Sundaram
Abstract:: Two approaches to the tricyclic core of the furanoeremophilane sesquiterpenoids are described. The first approach entails a projected Diels-Alder/retro Diels-Alder reaction of an acetylenic oxazole 64. Construction of the pivotal aldehyde 67 commenced from ketone 68. The acetyenic moiety was then introduced via a Felkin-Ahn addition of lithiopropyne to aldehyde...
Resource Type:: Dissertation

Pre-service grief and loss preparation in CACREP accredited school counseling programs

Creator:: Low, Lori L.
Abstract:: Youth today experience high degrees of loss and change, resulting in grief (Goldman, 2001). Little evidence exists of school counselors' academic preparation in grief counseling. The purpose of this research study was to determine how CACREP school counseling programs prepare school counselors in the areas of grief and loss, including...
Resource Type:: Dissertation

Transcriptional repression mediated by a novel family of C₂H₂ zinc finger proteins

Creator:: Senawong, Thanaset
Abstract:: Two novel and highly related C₂H₂ zinc finger proteins (CTIP1/BCL11A/EVI9 and CTIP2/BCL11B/Rit1) have been implicated in COUP-TF signaling, etiology of myeloid and lymphoid malignancies, and hematopoietic cell development. However, the precise cellular function(s) and the contribution of these proteins to neoplastic processes and hematopoietic cell development remain unknown. The goal...
Resource Type:: Dissertation

Bone gains in adolescent athletes and non-athletes

Creator:: Rinder, Todd Anthony
Abstract:: Discordance in bone mass between young adult swimmers and soccer players may be a direct result of differences in bone loading patterns that influence bone mineralization during growth. Our aim was to evaluate whether sports participation (soccer and swimming) had an independent effect on bone mass accrual at the hip...
Resource Type:: Dissertation

Biochemical characterization and mutational analysis of human uracil-DNA glycosylase

Creator:: Chen, Cheng-Yao
Abstract:: PCR-based codon-specific random mutagenesis and site-specific mutagenesis were performed to construct a library of 18 amino acid changes at Arg276 in the conserved leucine-loop of the core catalytic domain of human uracil-DNA glycosylase (UNG). Each Arg276 mutant was then overproduced in E. coli cells and purified to apparent homogeneity by...
Resource Type:: Dissertation

Improving Pacific oyster (Crassostrea gigas) production through selective breeding

Creator:: Evans, Sanford, 1968-
Abstract:: Shellfish growers have expressed interest in developing high-yielding oyster strains through selective breeding. This dissertation has three objectives to help determine the effects of genetic and environmental variation on production traits (body weight, survival, and yield) of Pacific oysters grown in the Pacific Northwest. Objective 1: Determine if relative family...
Resource Type:: Dissertation

Radiographic validation and reliability of selected measures of pronation and biomechanical analysis of tarsal navicular displacement under static and dynamic loading conditions

Creator:: Hannigan-Downs, Kim
Abstract:: The navicular drop test (NDT), Feiss' line (FL) and standing foot angle (SFA) are clinical tests used to estimate the amount of pronation via inferior displacement of the tarsal navicular. Thirty-two patients (female and male, ages 18-65) who sought medical treatment for lower extremity pathologies participated in the study that...
Resource Type:: Dissertation

The complexity of nonresident father involvement in low-income families : mothers' perspectives

Creator:: Sano, Yoshie
Abstract:: The two studies of this dissertation examined mothers' perspectives of nonresident fathers' involvement in low-income families. The overall goal of these studies was to gain a more comprehensive understanding of nonresident fathers' involvement and its effect on family well-being. In the first study I applied a relatively new methodology, zero-inflated...
Resource Type:: Dissertation

Neural network imputation : a new fashion or a good tool

Creator:: Amer, Safaa R.
Abstract:: Most statistical surveys and data collection studies encounter missing data. A common solution to this problem is to discard observations with missing data while reporting the percentage of missing observations in different output tables. Imputation is a tool used to fill in the missing values. This dissertation introduces the missing...
Resource Type:: Dissertation

Selenium and trace metal accumulation in detrital-benthic food webs of lotic and lentic wetlands, Utah, USA

Creator:: Hillwalker, Wendy E.
Abstract:: Concentrations of selenium (Se), manganese (Mn), zinc (Zn), cadmium (Cd), lead (Pb) and arsenic (As) were measured in the water column, sediment and biota, in conjunction with selected physicochemical data, from representative wetland types at a mining site within Salt Lake County, Utah, USA. The selected field sites included Oolitic...
Resource Type:: Dissertation

Molecular genetics and enzymology of secondary metabolite biosynthesis. I, Isolation of natural product biosynthesis gene clusters from symbiotic marine organisms. II, Enzymology of blasticidin S biosynthesis

Creator:: Grochowski, Laura L.
Abstract:: Molecular genetic and enzymological techniques have been employed to study secondary metabolite biosynthesis. These investigations have focused on two projects: the cloning and heterologous expression of biosynthetic gene clusters from unculturable marine organisms and the characterization of individual enzymes involved in the biosynthesis of the antifungal agent blasticidin S. The...
Resource Type:: Dissertation

Chemical signaling and pheromone evolution in plethodontid salamanders

Creator:: Palmer, Catherine Anne
Abstract:: My dissertation focuses on the evolutionary forces that have shaped the chemical signaling system of plethodontid salamanders. Pheromones mediate two phases of plethodontid reproduction: mate attraction prior to courtship and female persuasion during courtship. Substrate-borne chemical signals are believed to play an important role in mate attraction for these animals....
Resource Type:: Dissertation

A role for maize ROP2 GTPase in the male gametophyte

Creator:: Carroll, Kirstin Arthur
Abstract:: ROP GTPases are crucial regulators of pollen tube growth. The Rop GTPase family in maize consists of nine known rop genes, ropl-rop9. A subset of these genes (rop2, rop8, and rop9) are expressed in pollen. The rop2 and rop9 genes are a highly conserved duplicate gene pair of ancient origin....
Resource Type:: Dissertation

Dynamic modeling, control and linear theory of a projectile equipped with a rotating internal part

Creator:: Frost, Geoffrey W.
Abstract:: Dynamic modeling of the atmospheric flight mechanics of a projectile equipped with an uncontrolled internal rotating disk is investigated and a modified projectile linear theory is established. It is shown through modeling of this type of projectile that several coefficients of the epicyclic dynamics are altered, leading to changes in...
Resource Type:: Dissertation

Becoming more Latino : the journey of an extension nutrition education program

Creator:: Hernandez, Rebecca
Abstract:: Latinos are the fastest growing minority group in the U.S. and are expected to be 25% of the population by the year 2050. Latinos also are more vulnerable and at higher risk for poor health outcomes including diabetes and other chronic health ailments than Anglos. Many of the serious effects...
Resource Type:: Dissertation

Steady-state analysis techniques for coupled device and circuit simulation

Creator:: Hu, Yutao
Abstract:: The focus of this work is on the steady-state analysis of RE circuits using a coupled device and circuit simulator. Efficient coupling algorithms for both the time-domain shooting method and the frequency-domain harmonic balance method have been developed. A modified Newton shooting method considerably improves the efficiency and reliability of...
Resource Type:: Dissertation

Olivine and plagioclase-hosted melt inclusions and their application to determining parental arc magmas

Creator:: Kohut, Edward John
Abstract:: Three broadly interrelated problems of critical significance to the proper interpretation of melt inclusion (MI) data are addressed in this thesis. The first issue, the petrogenesis of anorthitic plagioclase phenocrysts in MORB lavas, has relevance due to the presence of numerous MI in many high-An feldspars. This problem was addressed...
Resource Type:: Dissertation

High-performance delta-sigma analog-to-digital converters

Creator:: da Silva, Jose Barreiro
Abstract:: Multi-stage delta-sigma (ΔΣ) architectures, commonly known as MASH, are the preferred choice for analog-to-digital converters (ADCs) used in broadband communication applications, where high-resolution (above 14 bits) and high-bandwidth (several MHz) performances are required. Current state-of-the-art designs are capable of as much as 5-MS/s output data rates with 90-dB SNR. However,...
Resource Type:: Dissertation

Development of novel spray coated soft elastic gelatin capsule sustained release formulations of nifedipine, bioavailability and bioequivalence of verapamil HCL controlled release formulations, pharmacokinetics of terbinafine after single oral doses in raptors

Creator:: Fahmy, Sahar Abd El-Sattar
Abstract:: This dissertation describes the development of a new sustained release formulation of nifedipine. The new formulation was developed by coating commercially available immediate release soft elastic gelatin capsules using a spray coating technique with two different polymeric combinations. Dissolution studies were conducted and showed that controlled release of nifedipine was...
Resource Type:: Dissertation

Fecal Bacteroidetes host distributions and environmental source tracking

Creator:: Dick, Linda K.
Abstract:: Contamination of recreational and shellfish waters with fecal pollution is a major water quality issue with associated economic impacts and human health risks. Reliable fecal source identification and rapid, quantitative analyses are essential components of risk assessment. Enteric bacteria that are endemic to specific hosts have a potential role as...
Resource Type:: Dissertation

Resistance mechanisms of Port-Orford-cedar to Phytophthora lateralis

Creator:: Oh, Eunsung
Abstract:: Breeding Port-Orford-cedar for resistance to Phytophthora lateralis, a causal agent of root disease, begins by screening, through artificial inoculation, phenotypically resistant trees selected from natural stands. The successful program selected tolerant or resistant POC parent trees for the purpose of disease management. Candidate resistant POCs were used in my dissertation...
Resource Type:: Dissertation

Technology and meaning in natural resource management : the story-making role of GIS in the CLAMS project

Creator:: Duncan, Sally
Abstract:: The working hypothesis for this study is that the introduction of GIS technology into the ancient procedures of map-making has changed the map-making context sufficiently to require a revision of the way we think about, learn from, and use maps, specifically in the public involvement process in natural resource management....
Resource Type:: Dissertation

A landscape-scale assessment of plant communities, hydrologic processes, and state-and-transition theory in a Western juniper dominated ecosystem

Creator:: Petersen, Steven Lawrence
Abstract:: Western juniper has rapidly expanded into sagebrush steppe communities in the Intermountain West during the past 120 years. This expansion has occurred across a wide range of soil types and topographic positions. These plant communities, however, are typically treated in current peer-reviewed literature generically. The focus of this research is...
Resource Type:: Dissertation

Clinical pharmacokinetic simulation/modeling as a tool for therapeutic drug monitoring and dose adjustment in special patient populations

Creator:: Mohamed, Osama H.
Abstract:: This dissertation describes how to apply pharmacokinetic simulations and modeling in a clinical setting to monitor and adjust drug dosing in special patient populations. Pharmacokinetic simulations were used to investigate efficacy and risk of drug toxicity of a new dosing regimen for aminoglycoside antibiotics when administered to renal failure patients....
Resource Type:: Dissertation

Numerical study of mass transfer enhanced by theromocapillary convection in a 2-D microscale channel

Creator:: Kittidacha, Witoon
Abstract:: The effect of unsteady thermocapillary convection on the mass transfer rate of a solute between two immiscible liquids within a rectangular microscale channel with differentially heated sidewalls was numerically investigated. A computational fluid dynamic code in Fortran77 was developed using the finite volume method with Marker and Cell (MAC) technique...
Resource Type:: Dissertation

Search Constraints

Search Results

Limit your search