Digital Commons Network^™

Eddy Impaction As An Ash Deposition Mechanism: A Theoretical And Experimental Investigation, Minmin Li

Theses and Dissertations

The eddy impaction ash deposition model derived and validated in this document predicts eddy impaction rates as a function of turbulence intensity, boundary layer thickness, and gas velocity. The experimental apparatus introduces small particles (200 nm, 25 µm, and 500 µm diameter) into a gas stream flowing through a horizontal pipe (Re 2,300-8,000). The particles deposit on the pipe wall and the total mass of impacted particles provides a measure of collection efficiency. Experimental results indicate deposition velocity increases with Reynolds number, consistent with eddy impaction theory and based on increased turbulent energy. Eddy impaction also increases with particle size …

Marker Discovery In Allotetraploid Cotton Using 454 Pyrosequencing, Robert L. Byers

Theses and Dissertations

A narrow germplasm base and a complex allotetraploid genome have historically made the discovery of single nucleotide polymorphism (SNP) markers difficult in cotton (Gossypium hirsutum). We conducted a genome reduction experiment to identify SNPs from two accessions of G. hirsutum and two accessions of G. barbadense. Approximately 2 million sequence reads were assembled into contigs with an N50 of 508 bp and analyzed for SNPs. A total of 11,834 and 1,679 SNPs between the accessions G. hirsutum and G. barbadense, respectively, were identified with highly conservative parameters (a minimum read depth of 8x at each SNP …

Thin-Ideal Internalization, Body Misperception, And Their Association With Weight Control Behaviors Among Adolescent Girls, Erin Lindsey Moore

Theses and Dissertations

Negative body image and preoccupation with weight are the norm for most women and girls in Western society, despite their potentially harmful consequences for psychological and physical wellness. While we know that many in this population experience negative feelings towards their bodies, we do not know if their beliefs about their body size are accurate and what effect a correct or incorrect assessment of one's body size has in terms of actual behavior. I examine this question among adolescent girls using data from the 2002 Health Behaviors in School-Age Children Survey. With a sample of 2,784 girls between the ages …

Higher Education In Native American Communities: Who Graduates And Why?, Ramon Francisco Castillo Ii

Theses and Dissertations

In this case study, I examine the graduation patterns of students attending Chief Dull Knife College located on the Northern Cheyenne Reservation in Lame Deer, Montana. While comparing the characteristics of students attending this college with that of two-year colleges nationally and tribal schools throughout the nation, we begin to understand the unique situation that this community faces. With the use of logistic and linear regressions, I explored the characteristics of those who graduate and ask the question, who graduates and what makes them unique? This study found that the credits attempted per semester, the number of credits they earned …

Mechanical Characterization Of The Interspinous Ligament Using Anisotropic Small Punch Testing, Rachel Jane Bradshaw

Theses and Dissertations

Objective: The objective of this work was to characterize the nonlinear anisotropic material constitutive response of the interspinous ligament (ISL).

Methods: Cadaveric test samples of the interspinous ligament were tested using the anisotropic small punch test. The measured force-displacement response served as experimental input into a system identification optimization routine to determine the constitutive material parameters that replicated the measured material response.

Results: The constitutive behavior of the ISL is notably different from that reported for knee, shoulder, and hip ligaments. Specifically, the high collagen fiber content and unique collagen architecture provided a stiffer material response. The results from the …

Community Satisfaction, Community Attachment, Community Experience, Internet Use And Internet Access In Rural Utah Communities, Tisah M. Quarnberg

Theses and Dissertations

This study examines the impact of the Internet on rural community satisfaction, attachment and overall experience. With the geographic dispersion of social networks, the majority of the population has a greater need for long-distance social networking. The Internet has the potential to mitigate distance and connect social networks much faster than letter writing or face-to-face visits. While the Internet is available, to at least some extent, in rural communities in Utah, does it positively affect overall perceptions of community life? This study finds that this is not the case. There is a negative relationship between Internet use and community satisfaction …

The Effects Of Β-Amyloid On Α7 Nicotinic Acetylcholine Receptors Expressed In Xenopus Oocytes, Malia L. Anderson

Theses and Dissertations

The exact mechanism and progression of Alzheimer's disease (AD) at present is not fully understood. In patients suffering from AD, damage to the hippocampal region and impairment of learning and memory is present. It is also known that a buildup of β-amyloid plaques occur in AD patients and that β-amyloid interacts with some subtypes of neuronal nicotinic acetylcholine receptors (neuronal nAChRs). These receptors are composed of five subunits. The most prevalent nAChR subunit composition through the brain as a whole is α7. Previous data produced from our lab suggests that α7 nAChRs are also one of the most prevalent subunits …

Characterization Of The Mechanical Response Of The Lumbar Spine, Shannon Alisa Zirbel

Theses and Dissertations

The primary objective of this research is to associate lumbar segmental mechanical response with intervertebral disc degeneration under physiologic testing conditions. Because no mathematical model exists for lumbar spine segmental rotations, a portion of this thesis evaluates potential methods for curve fitting the torque-rotation curves. The Dual Inflection Point (DIP) Boltzmann equation was developed during the course of this research and is presented here as a method for fitting spinal motion data wherein a physical meaning can be assigned to each of the model coefficients. This model can tell us more about the effects of degeneration, testing conditions, and other …

Comparing The Effects Of Two Forms Of Dynamic Corrective Feedback On Four Characteristics Of English Language Learner Writing, Judson Mc Kay Hart

Theses and Dissertations

Particular English language learners have a need to demonstrate high levels of accuracy in their written and spoken language production. Dynamic corrective feedback (dynamic CF) has been shown to facilitate L2 learner written accuracy attainment through providing manageable, meaningful, timely and constant feedback on authentic and frequent written language production. The research of this thesis examined the benefits of altering the dynamic CF model to be responsive to students' spoken production rather than solely their written production and measured the impact this adaptation would have on the established benefits of the instructional strategy on students' gains in written accuracy. The …

The Molecular Mechanism Of Migraine, Kristin Dawn Watson

Theses and Dissertations

Migraine is a common, episodic neurological disorder that includes headache, nausea and hypersensitivity to sensory stimuli. During the headache phase of migraine, migraine patients can be especially hypersensitive to thermal stimuli. The unpredictable and episodic nature of migraine makes it difficult to treat and much of the mechanism of migraine has yet to be elucidated. A T44A substitution in casein kinase 1δ is inherited with migraine with aura. A transgenic mouse model suggests that animals with this mutation exhibit increased sensitivity to thermal stimuli after injection with nitroglycerin (NTG). We performed behavior assays that measure animal responses to thermal stimuli, …

Structures Of Poliovirus And Antibody Complexes Reveal Movements Of The Capsid Protein Vp1 During Cell Entry, Jun Lin

Theses and Dissertations

In the infection process, native poliovirus (160S) first converts to a cell-entry intermediate (135S) particle, which causes the externalization of capsid proteins VP4 and the N-terminus of VP1 (residues 1-53). The externalization of these entities is followed by release of the RNA genome, leaving an empty (80S) particle. Three antibodies were utilized to track the location of VP1 residues in different states of poliovirus by cryogenic electron microscopy (cryo-EM). "P1" antibody binds to N-terminal residues 24-40 of VP1. Three-dimensional reconstruction of 135S-P1 showed that P1 binds to a prominent capsid peak known as the "propeller tip". In contrast, our initial …

Examining The Mediating Factors Between Religiosity And Pornography Use In Adolescents, Michael A. Steelman

Theses and Dissertations

The purpose of this study was to examine relations between adolescent religiosity and pornography use, and the roles of self-regulation, attitudes towards pornography, and social control as mediators of these relations. It was hypothesized that religiosity would protect adolescents from exposure to pornography by increasing their self-regulation capacity, their conservative attitudes about pornography, and their perceived social norms regarding pornography. The sample consisted of 419 adolescents (ages 15 - 18 years; M age = 15.68, SD = .98; 56% male) recruited online from across the U.S. Participants completed an online survey. All variables were bivariately associated as expected. Path models …

Reproductive Success And Soil Seed Bank Characteristics Of Astragalus Ampullarioides And A. Holmgreniorum (Fabaceae): Two Rare Endemics Of Southwestern Utah, Allyson B. Searle

Theses and Dissertations

Astragalus ampullarioides and A. holmgreniorum are two rare endemics of southwestern Utah. Over two consecutive field seasons (2009-2010) we examined pre-emergent reproductive success, based on F/F and S/O ratios, from populations of both Astragalus ampullarioides and A. holmgreniorum, estimated the density of the soil seed bank of A. holmgreniorum as a measure of potential post-emergent reproductive success, and estimated seed persistence within the soil seed bank. Fruit/flower (F/F) ratios and seed/ovule (S/O) ratios varied significantly between populations and among years in both species, and showed low reproductive output in both taxa. In Astragalus ampullarioides F/F and S/O were 0.06±0.01 …

Dismissed With Prejudice: Gender Inequality In The Utah Legal Market, Collin Read Flake

Theses and Dissertations

With the increasing feminization of the legal profession in the United States over the last half century, past research has documented the prevalence and transformation of gender inequality in law firms. However, relatively little is known about gender inequality in small, conservative legal markets like Utah. This thesis examines data from the 2008-2009 Utah Attorney Advancement and Retention Survey. The analyses indicate that relative to their male colleagues, women earned less in 2007 and are less likely to procure higher quality job assignments than their peers. The most promising explanations for these disparities include employment sector, gender and motherhood statuses, …

Novel Ion Trap Made Using Lithographically Patterned Plates, Ying Peng

Theses and Dissertations

A new approach of making ion trap mass analyzers was developed in which trapping fields are created in the space between two ceramic plates. Based on microfabrication technology, a series of independently-adjustable electrode rings is lithographically patterned on the facing surfaces of each ceramic plate. The trapping field can be modified or fine-tuned simply by changing the RF amplitude applied to each electrode ring. By adjusting the potential function applied to the plates, arbitrary trapping fields can be created using the same set of ceramic plates. Unlike conventional ion traps, the electrodes of planar ion traps have a non-equipotential surface, …

Genome Snapshot And Molecular Marker Development In Penstemon (Plantaginaceae), Rhyan B. Dockter

Theses and Dissertations

Penstemon Mitchell (Plantaginaceae) is one of the largest, most diverse plant genera in North America. Their unique diversity, paired with their drought-tolerance and overall hardiness, give Penstemon a vast amount of potential in the landscaping industry—especially in the more arid western United States where they naturally thrive. In order to develop Penstemon lines for more widespread commercial and private landscaping use, we must improve our understanding of the vast genetic diversity of the genus on a molecular level. In this study we utilize genome reduction and barcoding to optimize 454-pyrosequencing in four target species of Penstemon (P. cyananthus, …

Multiplicity: An Organizing Principle For Cancers And Somatic Mutations, Lewis J. Frey, Stephen R. Piccolo, Mary E. Edgerton

Faculty Publications

Background: With the advent of whole-genome analysis for profiling tumor tissue, a pressing need has emerged for principled methods of organizing the large amounts of resulting genomic information. We propose the concept of multiplicity measures on cancer and gene networks to organize the information in a clinically meaningful manner. Multiplicity applied in this context extends Fearon and Vogelstein’s multi-hit genetic model of colorectal carcinoma across multiple cancers.

Methods: Using the Catalogue of Somatic Mutations in Cancer (COSMIC), we construct networks of interacting cancers and genes. Multiplicity is calculated by evaluating the number of cancers and genes linked by the measurement …

Integration Of Micropore And Nanopore Features With Optofluidic Waveguides For Single Particle Sensing, Matthew R. Holmes

Theses and Dissertations

This dissertation outlines the research and development of ground-breaking nanometer sized openings (nanopores) integrated with an on-chip optofluidic platform. This platform represents a significant advancement for single nanoparticle sensing. In this work specifically, the integrated optofluidic platform has been used to electrically and optically filter and detect single nanoparticles using ionic current blockade and fluorescence experiments. The correlation of electrical and optical signal has provided the highest sensitivity single nanoparticle measurements ever taken with integrated optofluidic platforms. The particular optofluidic platform used for this work is an antiresonant reflecting optical waveguide (ARROW). ARROW hollow and solid core waveguides are interference …

Devices And Methods For Electro-Physical Transport Of Dna Across Cell Membranes, Quentin Theodore Aten

Theses and Dissertations

A novel method for charged macromolecule delivery, called nanoinjection, has been developed at Brigham Young University. Nanoinjection combines micro-fabrication technology, mechanism design, and nano-scale electrical phenomenon to transport exogenous DNA across cell membranes on a nano-featured lance. DNA is electrically accumulated on the lance, precision movements of microelectromechanical systems (MEMS) physically insert the lance into cell, and DNA is electrically released from the lance into the cell. Penetration into the cell is achieved through a two-phase, self-reconfiguring metamorphic mechanism. The surface-micromachined, metamorphic nanoinjector mechanism elevates the lance above the fabrication substrate, then translates in-plane at a constant height as the …

Transcriptome Characterization And Polymorphism Detection In Subspecies Of Big Sagebrush (Artemisia Tridentata), Prabin Bajgain

Theses and Dissertations

Big sagebrush (Artemisia tridentata) is one of the ecologically most important shrub species in western North America. The species serves as a major source of food and habitat for the near-threatened sage grouse and various other fauna. Habitat loss due to a combination of disturbances followed by establishment of invasive plant species is considered as a serious threat to sustainability of the big sagebrush ecosystem. Because of its importance, restoration of this species is very crucial to those dependent on big sagebrush community. However, restoration of big sagebrush carried out by using diverse seed source can lead to …

A Multi-Frequency Inverse Source Problem For The Helmholtz Equation, Sebastian Ignacio Acosta

Theses and Dissertations

The inverse source problem for the Helmholtz equation is studied. An unknown source is to be identified from the knowledge of its radiated wave. The focus is placed on the effect that multi-frequency data has on establishing uniqueness. In particular, we prove that data obtained from finitely many frequencies is not sufficient. On the other hand, if the frequency varies within an open interval of the positive real line, then the source is determined uniquely. An algorithm is based on an incomplete Fourier transform of the measured data and we establish an error estimate under certain regularity assumptions on the …

Adaptation Of An Adolescent Coping Assessment For Outdoor Adventure, Melissa S. Russell

Theses and Dissertations

The purpose of this study was to adapt a measure for coping in outdoor adventure activities that reliable and valid inferences could be made. To do this, the constructs were clearly defined; relevant items were written representing the constructs. An expert panel reviewed the items for content validity, and the instrument was administered to subjects to gather evidence supporting the reliability and validity of inferences. The instrument adapted will provide a foundation for future research and understanding related to outdoor adventure coping skills. In addition, evidence supporting the reliability and validity of inferences of the assessment serve to measure outcomes …

Lady Libertines, Female Fops, And Lady Julia Fulbank: Aphra Behn's Extraordinary Female Characters., Sarah Audine Amundsen

Theses and Dissertations

Aphra Behn has, throughout her life and subsequent years, been both demonized as a writer of bawdy and licentious plays and poetry as well as being hailed as the forerunner of female writers. She was a woman writing in a man's world, and not only survived the experience, but was exceptionally successful in her efforts. While so little is known about her background, the numerous plays she has left behind demonstrate a skilled author in many forms, as well as a creative and innovative storyteller. This thesis will examine how Behn used the traditional theatrical forms of the time and …

The Effects Of The Rebound Diathermy Unit, Megapulse Ii Shortwave Diathermy Unit And Moist Hot Packs On Tissue Temperature Increase Of The Triceps Surae Muscle Group, Amanda Rose Hawkes

Theses and Dissertations

Context: Clinicians use a number of superficial and deep heating modalities, including pulsed shortwave diathermy (PSWD) and moist hot packs, in the clinical setting. Recently, a continuous diathermy unit called ReBound was introduced into the clinical setting. Its effectiveness as a heating modality is unknown. Objective: To compare the effects of PSWD, moist hot packs and the ReBound unit on tissue temperature in the triceps surae muscle. Design: A 3 x 27 factorial cross-over design with repeated measures. Setting: University research laboratory. Subjects: Twelve healthy college-aged volunteers (4 men, 8 women; age = 22.2 ± 2.25; calf subcutaneous fat thickness …

Investigating A Model Reversed-Phase Liquid Chromatography Stationary Phase With Vibrationally Resonant Sum Frequency Generation Spectroscopy, Arthur D. Quast

Theses and Dissertations

Reversed-phase liquid chromatography (RPLC) is a widely used technique for analytical separations but routinely requires empirical optimization. Gaining a better understanding of the molecular reasons for retention may mean more efficient separations with fewer trial and error runs to obtain optimized separations. Vibrationally resonant sum frequency generation (VR-SFG) is a surface specific technique that has allowed for in situ examination of model RPLC stationary phases under various solvent and pressure conditions. In order to improve on past work with model RPLC stationary phases two challenges had to be overcome. First, improved vibrational mode assignments of the C18 stationary phase were …

Investigating The Influence Of Computer Programs On Perception And Application Of Mathematical Skills, Neil M. Bly

Theses and Dissertations

Existing research suggests an intuitive relationship between mathematics and computer programming. These previous studies have focused primarily on the cognitive connection and have ignored the potential impact of programming on an individual's perception and application of mathematical skills. By surveying and interviewing a variety of participants, this study aims to provide a descriptive foundation for the experiential side of cognitive correlations and causalities. These phenomenological accounts, garnered from individual interviews of seven different programmers, indicate four specific areas of interest. First, learning to program provided context for many abstract concepts. Second, programming illustrated the important distinction between understanding the application …

Cross-Cultural Ecotheology In The Poetry Of Li-Young Lee, Sienna Miquel Palmer Dittmer

Theses and Dissertations

This thesis explores the cross-cultural ecotheology of contemporary American poet Li-Young Lee by looking at the intersection of the human, the natural, and the sacred in his poetry. Close readings of Lee's poetic encounters with roses, persimmons, trees, wind, and light through the lens of Christianity and Daoism illustrate the way Lee is able to merge the Eastern concepts of interconnection and mutual harmony with Western ideas of sacredness and divinity. This discussion places Lee in direct conversation with modern and contemporary ecopoets who use the creative energy of language to express our moral and ethical responsibility to the world …

Antioxidants In Cancer Research And Prevention: Assay Comparison, Structure-Function Analysis, And Food Product Analysis, Andrew Robert Garrett

Theses and Dissertations

Recent epidemiological studies have suggested that the development and progression of several chronic diseases may be initiated or augmented by oxidative stress. Reactive oxygen species and reactive nitrogen species react readily with and can damage nucleic acids, proteins, and lipids. While biological systems are equipped antioxidant defenses to cope with oxidative stress, oxidative damage may still occur when oxidative stress overwhelms antioxidant defenses. This damage, if left unchecked, may lead to a variety of degenerative diseases, including heart disease, Alzheimer's Disease, Parkinson's Disease and cancer. Several assays have been designed to describe the antioxidant activity of various phytochemicals, vitamins, and …

Principles Of Learning: A Conceptual Framework For Domain-Specific Theories Of Learning, Christian J. Weibell

Theses and Dissertations

This study is predicated on the belief that there does not now exist, nor will there ever exist, any single theory of learning that is broad enough to account for all types of learning yet specific enough to be maximally useful in practical application. Perhaps this dichotomy is the reason for the apparent gap between existing theories of learning and the practice of instructional design. As an alternative to any supposed grand theory of learning—and following the lead of prominent thinkers in the fields of clinical psychology and language teaching—this study proposes a shift toward principles. It presents a principle-based …

How Students Experience Teach-One-Another Activities In Online Courses At Brigham Young University-Idaho, Joshua Alan Holt

Theses and Dissertations

As online learning enrollments rapidly increase, it is vital to explore effective course designs that deepen students' learning experiences. This multiple-case study explores four online courses at Brigham Young University–Idaho that include learning activities where students learned through Teach One Another activities. Teach One Another is similar to Reciprocal Peer Learning where students simultaneously learn and contribute to their peers' learning. Findings across the cases of this study show that Teach One Another activities in online courses encourage students to be accountable and motivated to complete individual course work as well as group assignments. As students learn to build trusting …