Digital Commons Network^™

Median Crossover Crashes In The Vicinity Of Interchanges On Utah Interstates, Katherine Elaine Winters

Theses and Dissertations

While not accounting for a significant proportion of overall crashes, median crossover crashes in the state of Utah do account for a significant proportion of interstate fatalities. Due to the seriousness of median crossover crashes in the state of Utah, the need exists to evaluate the impact of median crossover crashes in the state, to identify locations where median crossover crashes may be occurring at particularly high rates, and to identify methods to help mitigate these crashes. Previous research has noted that median crossover crash rates appear to increase in the vicinity of interchanges. The purpose of this research, therefore, …

Comprehension And Retention: The Effect Of Concrete Details And Causal Structure In Scientific Narrative, Wendi Michelle Wilcken

Theses and Dissertations

The purpose of this study was to examine two of the salient elements of instructional narratives as a guide to instructional practice. The literature summarized in this report discusses the theoretical basis for narrative impact on comprehension and retention, enumerates and defines possible salient narrative elements from the literature, and examines the instructional impact of two of these elements: concrete details and causal structure. This is intended to help provide guidance to instructional designers and teachers who desire to use narrative in science instruction. Participants included 94 high school physics students. An experimental research design of 2 (Gender) x 2 …

Physical Mapping Of Ribosomal Genes In New World Members Of The Genus Chenopodium Using Fluorescence In Situ Hybridization, Maria C. Sederberg

Theses and Dissertations

The genus Chenopodium contains many economically important species in the New World, but is relatively understudied and poorly understood, especially in terms of evolutionary relationships. A better understanding of the structure of this genus could significantly help in breeding efforts on its cultivated members, notably the tetraploid C. quinoa and also certain varieties of C. berlandieri, also tetraploid. Of special concern is determining which diploid weed species are the most likely ancestors for C. quinoa, C. berlandieri, and the other tetraploid members of subsection Cellulata. The phylogeny can be understood in part by examining the ribosomal RNA loci and observing …

Discovery And Initial Characterizations Of Neurofascin 155 High And Neurofascin 155 Low, Anthony Pomicter

Theses and Dissertations

This thesis contains the findings from four years of research regarding an oligodendrocyte protein named neurofascin 155. The role of this protein in maintaining adhesion between the myelin sheath of oligodendrocytes and the axons of neurons has become well established in recent years and the research presented here has revealed that while western blots have previously shown one protein/band representing neurofascin 155, there are two proteins/bands. These two proteins have been named neurofascin 155 high and neurofascin 155 low due to their previous inclusion in the single band. The work leading up to their discovery, findings, and the relevance of …

Avian Dispersal Of The Actinomycete Frankia Across A Barrier Island Landscape, Spencer Bissett

Theses and Dissertations

In the nutrient-poor soils characteristic of coastal environments, symbiotic association with the nitrogen-fixing root endosymbiont Frankia is essential to establishment and survival of the woody shrub Morella cerifera. Nutrient deficiency quickly becomes severe unless seedlings are infected by Frankia soon after germination. However, the means of arrival of Frankia prior to shrub establishment has not been determined. Using sterilized lab-grown M. cerifera seedlings and fecal samples collected from passerine birds on the Eastern Shore of Virginia, viability of avian dispersal of the bacteria was tested. Although passerine fecal samples did produce nodules on some sterilized M. cerifera seedlings, these experimental …

Interneuron Subtypes Are Differentially Altered In Malformed, Epileptogenic Cortex, Amanda George

Theses and Dissertations

The propensity for seizures in patients with epilepsy is due to underlying cortical hyperexcitability, the mechanisms of which are poorly understood. Particularly difficult to treat are patients with developmental malformations of cortex. Using the freeze-lesion rat model of one such malformation, polymicrogyria, we identified, in lesioned cortex, alterations in specific interneuron subpopulations that may promote hyperexcitability. Previous studies demonstrate increased excitatory input to the paramicrogyral region. An increase in the frequency of spontaneous excitatory postsynaptic currents (sEPSCs) recorded from pyramidal cells has also been shown. We report an increase in sEPSCs recorded from one subtype of interneuron, the low threshold-spiking …

Altered Vascular Function In A Rat Model Of Reduced Utero -Placental Perfusion., Cindy M. Anderson

Theses and Dissertations

The present study was designed to characterize vascular responsiveness and leptin signaling in small mesenteric and uterine arcuate arteries in a rat model of reduced uterine perfusion pressure. The reduced uterine perfusion pressure (RUPP) model was utilized to mimic the underlying pathology of preeclampsia. The uterine arteries and abdominal aortae of pregnant Sprague-Dawley rats were surgically constricted on day 14 of gestation. Systolic blood pressure measurements were obtained before and during pregnancy using a tail cuff measuring system. Weight was measured with each blood pressure evaluation. The rats were euthanized on gestational day 20. Fetal number, fetal weight and placental …

Experimental Polychondritis: Induced Vs. Spontaneous., Jennifer L. Lamoureux

Theses and Dissertations

We demonstrate evidence supporting two independent hypotheses related to experimental polychondritis: (1) co-expression of a “nonpathogenic” HLA-DQ allele with a “pathogenic” allele results in enhanced susceptibility to disease; and (2) age related immunological changes allow for the spontaneous onset of disease. Relapsing polychondritis (RP), a human autoimmune disease of unknown etiology in which cartilaginous sites are destroyed by cyclic inflammatory episodes, occurs most commonly during middle age. Collagen-induced polychondritis (CIP) develops in heterologous type II collagen (CII) immunized young (6–8 wk old) mice expressing HLA-DQ6α8β transgenes (tg) regardless of gender, and mirrors clinical RP. Although both DQ6αβ8αβ tg and DQ6α8β …

Cervical Extracellular Matrix Changes Due To Parturition, Rhonda R. Schafer

Theses and Dissertations

Cervical ripening involves an active process of extracellular matrix remodeling to produce dramatic changes in the biomechanical properties of the cervix. Comparison of temporal changes in proteoglycan synthesis, glycosaminoglycan accumulation, and matrix metalloproteinase (MMP) activity in rat cervices related to pregnancy will allow us to better understand the sequence of events that control cervical ripening. To maintain clinical relevance, we will compare the effects of clinically used cervical ripening agents on extracellular matrix synthesis and degradation using human cervical fibroblasts in vitro.

Sprague-Dawley rat cervices were radiolabeled in organ and extracted. Measurements of wet weight shows significant increases at gestational …

The Claustrum In Autism And Typically Developing Male Children: A Quantitative Mri Study, Warren B. Davis

Theses and Dissertations

The claustrum (Cl) is a subcortical gray-matter structure housed between the external capsule medially and the extreme capsule laterally. Due to its extensive reciprocal connections throughout the brain, it has been implicated in consciousness and other higher order functions including linking behavior and emotion. Such linkage may be important in understanding the neurobiology of autism since other cortical and subcortical regions including the spatially and ontologically related basal ganglia, as well as limbic structures, have been implicated in the disorder. Participants were males with autism (n=16) and typically developing (TD; n=14) matched for head circumference and age. The Cl and …

Making Sense Of Their World: Sensory Awareness And Sensory Reactivity As Predictors Of Social Interaction In Early Childhood, Cortney Anne Evans

Theses and Dissertations

The purposes of this study were to (a) test the validity of a sensory reactivity measure adapted for parents of preschool-age children, (b) examine if different modalities of sensory reactivity (i.e. smell, touch, taste, etc.) emerge together or if differing thresholds of reactivity exist between sensory modalities, (c) see how parental ratings of preschoolers' sensory reactivity are related to children's behaviors in the classroom, and (d) see if sensory reactivity bears different relationships to children's social behaviors than do other aspects of temperament. A total of 260 parents (242 mothers, 18 fathers) and 10 teachers of 260 children (131 male, …

Identification Of Pharmacological And Molecular Mechanisms Involved In Nicotine Withdrawal, Kia Jackson

Theses and Dissertations

Tobacco dependence is the leading cause of preventable death in the United States. Despite currently available smoking cessation therapies, there is a high rate of relapse in smoking among those attempting to quit. While the somatic signs of nicotine withdrawal (insomnia, increased appetite, weight gain) contribute to the continuation of smoking behavior, it has been hypothesized that the affective signs (depression, anxiety, craving, irritability) are greater motivators of relapse and continued tobacco use. There are few studies that assess the molecular and receptor-mediated mechanisms of nicotine withdrawal; therefore, our studies focus on identifying the nicotinic acetylcholine receptor (nAChR) subtypes and …

Application Of Shortest-Path Network Analysis To Identify Genes That Modulate Longevity In Saccharomyces Cerevisiae, Jr Managbanag

Theses and Dissertations

Shortest-path network analysis was employed to identify novel genes that modulate longevity in the baker’s yeast Saccharomyces cerevisiae. Based upon a set of previously reported genes associated with increased life span, a shortest path network algorithm was applied to a pre-existing protein-protein interaction dataset in order to construct a shortest-path longevity network. To validate this network, the replicative aging potential of 88 single gene deletion strains corresponding to predicted components of the shortest path longevity network was determined. The 88 single-gene deletion strains identified by a network approach are significantly enriched for mutation conferring both increased and decreased replicative life …

Combat Identification Using Multiple Tuav Swarm, Younin Kang

Theses and Dissertations

In modern warfare, Tactical Unmanned Aerial Vehicles (TUAVs) are rapidly taking on a leading role in traditional and non-traditional ISR, to include Automatic Target Recognition (ATR). However, additional advancements in processors and sensors on TUAVs are still needed before they can be widely employed as a primary source for positive identification in the Combat Identification (CID) process. Cost is a driving factor for operating an ATR system using multiple TUAVs. The cost of high quality sensors appropriate for a single TUAV can be significantly higher than less sophisticated sensors suitable for deployment on a group, or swarm, of coordinated TUAVs. …

Interoperability Measurement, Thomas C. Ford

Theses and Dissertations

This research presents an inaugural general method of measuring the collaborative and confrontational interoperability of a heterogeneous set of systems in the context of an operational process. The method is holistic, fundamental, flexible, and mathematical in nature and accommodates all types of systems and interoperations. The method relates the interoperability measurement to measures of operational effectiveness for confrontational operational processes. Extant leveling methods of describing interoperability are shown to be a special case of the more general method given in this research and the general interoperability measurement method is demonstrated through the presentation of coalition interoperability, suppression of enemy air …

Using Simulation Optimization To Construct Efficient Screening Strategies For Cervical Cancer, Christodoulos Foufoulides

Theses and Dissertations

Cervical cancer is the second most common type of cancer in women worldwide. Because cervical cancer is usually asymptomatic until the disease is in its advanced stages, cervical screening is of central importance towards combating cervical cancer. Alternative screening strategies are evaluated from an economic point of view through cost-effectiveness analysis. In the literature however, studies perform cost-effectiveness analysis on a limited number of de facto or predetermined screening policies. At present, no attempt has been made to construct efficient screening strategies through optimization, before cost-effectiveness analysis is applied. In this study simulation optimization is used to construct efficient screening …

Nucleoside Diphosphate Kinase Isoforms Associated With Mitochondria In Rat And Human., Dean Allen Frolich

Theses and Dissertations

Nucleoside diphosphate kinases (NDP kinases) are a family of enzymes that transfer the gamma-phosphate group from a NTP (nucleoside triphosphate) to a NDP (nucleoside diphosphate). The reaction follows a ping-pong mechanism in which the enzyme is transiently phosphorylated on a conserved histidine residue. In the cell, activity appears to be ubiquitous as it is associated with the cytosol, nucleus, mitochondria and plasma membrane. NDP kinase enzymatic activity has been demonstrated in a variety of tissues. The classical role proposed for NDP kinase in mitochondrial matrix is the transfer of a phosphoryl group from GTP (produced in the TCA cycle) to …

Development Of A Definition, Classification System, And Model For Cultural Geology., Lloyd W. Mitchell Iii

Theses and Dissertations

The concept for this study is based upon a personal interest by the author, an American Indian, in promoting cultural perspectives in undergraduate college teaching and learning environments. Most academicians recognize that merged fields can enhance undergraduate curricula. However, conflict may occur when instructors attempt to merge social science fields such as history or philosophy with geoscience fields such as mining and geomorphology. For example, ideologies of Earth structures derived from scientific methodologies may conflict with historical and spiritual understandings of Earth structures held by American Indians. Specifically, this study addresses the problem of how to combine cultural studies with …

Identification Of Virulence Determinants For Streptococcus Sanguinis Infective Endocarditis, Lauren Turner

Theses and Dissertations

Streptococcus sanguinis is the second most common causative agent of bacterial infective endocarditis (IE). Risk of S. sanguinis IE is dependent on pre-disposing damage to the heart valve endothelium, which results in deposition of clotting factors for formation of a sterile thrombus (referred to as vegetation). Despite medical advances, high mortality and morbidity rates persist. Molecular characterization of S. sanguinis virulence determinants may enable development of prevention methods. In a previous screen for S. sanguinis virulence determinants by signature-tagged mutagenesis (STM) an attenuated mutant was identified with a transposon insertion in the nrdD gene, encoding an anaerobic ribonucleotide reductase. Evaluation …

On Graph Isomorphism And The Pagerank Algorithm, Christopher J. Augeri

Theses and Dissertations

A graph is a key construct for expressing relationships among objects, such as the radio connectivity between nodes contained in an unmanned vehicle swarm. The study of such networks may include ranking nodes based on importance, for example, by applying the PageRank algorithm used in some search engines to order their query responses. The PageRank values correspond to a unique eigenvector typically computed by applying the power method, an iterative technique based on matrix multiplication. The first new result described herein is a lower bound on the execution time of the PageRank algorithm that is derived by applying standard assumptions …

Risky Behaviors Among University Students: The American College Health Survey 2000 And 2002 At The University Of North Dakota., Alan Allery

Theses and Dissertations

Health promotion professionals lack data regarding incidence and prevalence regarding risky behavior that University of North Dakota (UND) students engage in on a regular basis. Because of the lack of data and analysis, professionals were unable to develop a strategic plan that included science based interventions to reduce risky behavior and improve health status. The researcher used the health belief model as a theoretical framework for the study. A comparison of data from National College Health Surveys conducted at UND, in 2000 and 2002 to determine changes in behavior from 2000 to 2002. The results were also compared with a …

The Antioxidant Defense Network: Synergistic Combinations To Prevent Oxidative Damage, Amy Marie Clement

Theses and Dissertations

One of the matchless ironies of the human body is its requirement for the highly reactive oxygen molecule, which has been clearly implicated in many diseases and the aging processes. Oxidants produced by metabolic processes damage cells by starting chemical chain reactions including oxidation of DNA and proteins as well as lipid peroxidation. Damage to DNA can cause mutations and lead to cancer if not reversed by DNA repair mechanisms. Damage to proteins causes enzyme inhibition, denaturation and protein degradation. Lipid peroxidation can cause cell lysis as well as creating mutagenic and carcinogenic by-products. The human body contains antioxidants and …

Domain Duplication, Darwinian Selection, And The Origin Of The Globulin Seed Storage Proteins, Nathaniel S. Cannon

Theses and Dissertations

The seed storage globulins found among virtually all spermatophytes comprise a multi-gene family of proteins with ancient evolutionary origins. The two main groups of storage globulins include the legumins (11S) and vicilins (7S), both of which play a main role in protein deposition and storage in the seed endosperm. Composed of two cupin domains (bicupin), these proteins have been recently noted not only for their close structural relationships among the two subfamilies (7S and 11S) but also for their similarity to other proteins such as germin-like proteins (GLP's), bacterial oxalate decarboxylases, and other cupin containing proteins. Previous studies have investigated …

Adrenergic Modulation Of Ca1 Neuron Activity, Kristin L. Hillman

Theses and Dissertations

Adrenergic receptors (ARs) represent a family of G protein-coupled receptors endogenously activated by norepinephrine and epinephrine. One area of the brain where AR activation modulates cellular activity is CA1 hippocampus, however it is not known which AR subtypes are specifically involved, nor the mechanism behind the AR-mediated changes in activity. The goal of this study was thus two-fold; (1) Identify the specific AR subtypes expressed in CA1, and (2) Identify the mechanism by which AR activation changes CA1 neuron excitability. I set forth the hypothesis that α1B-AR activation initiates phospholipase C (PLC) signaling in CA1 interneurons, causing them to depolarize …

Adequacy Of Labor Epidural Information For Informed Consent, Darla J. Adams

Theses and Dissertations

Legally and ethically, obtaining informed consent for labor epidural analgesia means that the patient has a substantial understanding of the risks and benefits of the procedure. The purpose of this study was to determine if labor epidural analgesia education provided by Certified Registered Nurse Anesthetists (CRNAs) to expectant women during antenatal childbirth education classes improved the recall of risks associated with labor epidural analgesia. This study also determined pregnant women's sources of labor epidural information and the perceived adequacy of that information. The role of the antenatal childbirth education class as an opportunity for labor epidural education from trained anesthesia …

Characterization Of Adrenergic Receptor Subtypes In The Rodent Hippocampus, Christopher A. Knudson

Theses and Dissertations

Catecholaminergic input, acting through adrenergic receptors (AR), serves an important role in regulating the activity of the hippocampus; however, the synaptic elements whereby the abundant input mediates its actions remains obscure. Immunohistochemical and molecular biological techniques and a variety of experimental animal models, were used to examine the adrenergic receptor profiles displayed by distinct populations of neurons (interneurons and principal cells) or glial in rodent hippocampus. In the adult rat, immunoreactive puncta for eight of the nine adrenergic receptor subtypes were differentially distributed amongst regional glia, blood vessels, and neurons of the subiculum, hippocampus proper and dentate gyrus. Developmentally, there …

Historic Origin, Range Expansion, And Habitat Suitability Of Introduced Wild Pigs (Sus Scrofa) In California, Ronald E. Loggins

Theses and Dissertations

This study describes this historic origin, recent range expansion, and a generalized habitat suitability model for wild pigs (Sus scrofa ) in California. The genetic origins of wild pigs in California was determined to be of European and Asian descent by comparing published mitochondrial DNA (mtDNA) sequence data from European and Asian wild and domestic pigs with 107 wild pig mtDNA sequences from California. Based on the clustering of mtDNA genotypes, the recent range expansion of wild pigs in California was a function of both natural range expansion and multiple hunter related introductions. Analysis of the range expansion of wild …

Brownian Dynamics Simulations Of Interactions Between Aldolase, Gapdh Or Ldh With Cytoskeletal Proteins, Eric N. Njabon

Theses and Dissertations

One potentially important step in the compartmentation of glycolysis is the binding of glycoltic enzymes including: fructose-1 .6-biphosphate aldolase (aldolase), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) or lactate dehydrogenase (LDH) isoforms to cytoskeletal proteins like: F-actin or tubulin which is the major building block of microtubules. Tetrameric LOH can have different isoforms resulting from all possible combination of the muscle (M) or heart (H) type monomers. The LDH mixed tetrameric isoforms, LDH-M3H, LDH-MMHH, LDH-MHMH, LDH-MHHM and LDH-MH3, give distinctive electrostatic potentials and charges. If the positive electrostatic potential region between subunits A/D and subunits B/C, remains intact (such as in M3H) the mixed …

Effect Of Motivation On Superlative Responding Among Aviation And Psychology Students On The Mmpi-2, Peter A. Schmutzer

Theses and Dissertations

The purpose of this study was to determine whether highly motivating instructional conditions on MMPI-2 had a differential effect on the resulting MMPI-2 profiles of undergraduate aviation and psychology majors, particularly on the validity, clinical, and content scales. Of particular interest was the effect that instructional condition had on Superlative Self-Presentation (S) scale scores among aviation majors. One hundred and thirty-two upper-level undergraduate psychology and aviation majors at the University of North Dakota were randomly assigned to complete the MMPI-2 under one of two instructional conditions, "High Motivation" (HM) or "Standard Instructions" (SI). Results of the study showed that HM …

Cellular And Matrix Changes In Articular Cartilage Of The Disproportionate Micromelia Mouse Model Of Osteoarthritis, Crystal Noelle Smaldone

Theses and Dissertations

Osteoarthritis (OA) is a degenerative joint disease that affects more than 60% of Americans 65 and older. Because human subjects and samples are not readily available for research, animal models are an invaluable resource for the study of OA. Disproportionate micromelia (Dmm) is one such model that develops OA early in life due to a deletion in the c-propeptide of the Col2a1 gene. Light microscope analysis of the articular cartilage in Dmm has been completed, but is insufficient to show the cellular effects of the deletion mutation in Dmm in adequate detail. The present study explores the changes that occur …