Digital Commons Network^™

Bicycles And Transit: Weather Or Not: A Study On The Effect Of Weather And Air Quality On Bicycle-Transit, Bicycle, Rail Transit Counts In Denver, Christiana M. Fairfield

Electronic Theses and Dissertations

The movement of people and goods within metropolitan areas is critically important to the operational efficiency and functionality of cities. This study explores the influence of local weather conditions and the air quality index on bicycle-transit user in Denver, Colorado. Based on bicycle-transit having two key components, bicycle and transit, the effect of local weather conditions and the air quality index is also explored with bicycle use and rail-transit usage. Key findings include: (1) the most significant variable across all three modes is temperature, (2) for bicycle-transit and bicycle use, there is a steady increase in ridership as temperatures increase …

Geovisualization And Open-Source Web Mapping Of Big Origin-Destination Data, A Test Case, Joseph Hiebert

Electronic Theses and Dissertations

Migration plays a key role in determining the health and success of cities, counties, and countries. It also plays a key role in determining the health and wellbeing of the individuals and families that undergo a migration event. This has led many scholars to map and study global migration patterns to understand how and why people move. While migration data are powerful, the origin-destination (O-D), tabular format of the data can be hard to interpret. To make O-D data more powerful, geographers can lean on computer cartography and new geovisualization techniques to help decision makers make sense of large, complex …

Mis-Specification Of Functional Forms In Growth Mixture Modeling: A Monte Carlo Simulation, Richa Ghevarghese

Electronic Theses and Dissertations

Growth mixture modeling (GMM) is a methodological tool used to represent heterogeneity in longitudinal datasets through the identification of unobserved subgroups following qualitatively and quantitatively distinct trajectories in a population. These growth trajectories or functional forms are informed by the underlying developmental theory, are distinct to each subgroup, and form the core assumptions of the model. Therefore, the accuracy of the assumed functional forms of growth strongly influences substantive research and theories of growth. While there is evidence of mis-specified functional forms of growth in GMM literature, the weight of this violation has been largely overlooked. Current solutions to circumvent …

Measurements Of Atmospheric Radicals, Heather L. Runberg

Electronic Theses and Dissertations

Atmospheric particulate matter (PM) is a global health concern. PM_2.5 is formed primarily through combustion processes such as automobile use and industrial activity. Natural sources of PM_2.5 result from events like volcanos and wildfires. Upon inhalation, PM_2.5 is small enough to travel deep into the lungs where it can form reactive oxygen species (ROS), such as hydroxyl radical (OH), causing oxidative damage to pulmonary tissues. PM_2.5 has been linked to cardiopulmonary diseases such as asthma, chronic obstructive pulmonary disease (COPD), and high blood pressure.

PM_2.5 is small enough to remain aloft and travel many hundreds …

Monitoring Of State Transitions In Extreme Environment Application Materials Using Fiber Bragg Grating Sensors, Sabuj Khadka

Electronic Theses and Dissertations

By embedding both a single fiber Bragg grating (FBG) sensor and a thermocouple (TC) during the manufacturing for extreme environment applications of certain classes of materials such as metals and polymers, a novel in-situ approach was developed to precisely monitor their entire manufacturing processes. This novel monitoring technique was able to identify many characteristic points during the curing of room and high-temperature epoxies and the solidification processes of metal alloys composed of tin and bismuth which were selected in this research purely for verification purposes. Some of the characteristic points identified for the epoxies were: (i) the gel point, (ii) …

Esipt-Enabled Alkyne Migration Provides Rapid Access To Benzoxazinones, Andrés G. Muñoz

Electronic Theses and Dissertations

Benozoxazinones have long been of interest to agrochemical scientists and medicinal chemists because of their widespread biological activity. These scaffolds are also of interest to synthetic chemists, who recognize the utility of benzoxazinones for accessing functionalized heterocycles. The use of efavirenz, a benzoxazinone-based reverse transcriptase inhibitor used in the treatment of HIV-1, has brought increased attention to this privileged pharmacophore. While there exist numerous strategies for synthesizing benzoxazinones, methods that do not require the use of acutely toxic and environmentally hazardous reagents are lacking. Consequently, there is a need to develop new methods for constructing this valuable scaffold. Herein, we …

Extracellular Vesicles And Lipid Flippase Regulators In C. Elegans, Lauren Pitts

Electronic Theses and Dissertations

Extracellular vesicles (EVs) are membrane derived organelles released by all cell types and carry a vast array of cargos that can influence communication, development, and disease. One type of EV, known as microvesicles, form by budding directly from the plasma membrane in a process known as ectocytosis, however the mechanisms that govern this process are poorly understood. In C. elegans, the P4-ATPase, TAT-5, along with its activator, PAD-1, inhibit EV release from the plasma membrane by inhibiting phosphatidylethanolamine (PE) exposure on the outer leaflet of the plasma membrane. We identified 3 key domains of PAD-1 that are required to inhibit …

“This Rigid Curricular Way”: Evaluating Expectations In Collegiate Music Education, Sophie Ailsa Lewis

Electronic Theses and Dissertations

Conversations surrounding curricular reform are abound in music education today. Much of the literature on this topic explores how professors can adapt their teaching practices to the presumed needs of students in the classroom, but student voices are infrequently centered in these discussions.

This thesis examines the study of music in the collegiate setting from the student perspective. Using a survey which I designed and interviews that I conducted, I examine the disconnect between student values and those of the institutions they attend. I then put these student perspectives in conversation with existing literature.

I discovered that student experiences revolve …

A Labor Of Love: Extensive Exploitation Of Contract Music Workers, Malia Odekirk

Electronic Theses and Dissertations

Workers across the United States are reckoning with unfair labor conditions by unionizing and speaking out. Systemic undervaluing of many workers has created a climate of fear, hidden agendas, and pervasive labor misconduct. The pageantry/marching arts are no exception. As a cultural insider, I conducted interviews, had many informal conversations, and ran a large survey that uncovered how the marching arts exploit instructors extensively despite their experience, education, and efforts. A systematic proclivity toward late payments, abused contracts, egregiously low compensation, and free labor begs the question: how can programs continually mistreat instructors this way? I explore this question through …

Environmental Gradients Impact Key Leaf Traits In Riparian Trees, Amanda Malone

Electronic Theses and Dissertations

Specific leaf area (SLA) reflects a plant’s carbon investment per area and relates to generalized leaf economics spectrum growth strategies (LES). To fill gaps of knowledge about intraspecific SLA variation and why it is often inconsistent with the LES, we studied the response of two riparian tree species along the urban-rural gradient in Northeastern Colorado: an invasive, nitrogen-fixer with broad tolerances and a nitrogen-limited and shade-intolerant native. Despite these differences, the two species responded similarly, apart from the response to the urban-rural gradient, in which lower nitrogen in rural areas was associated with a more conservative strategy in the native …

The Pathophysiological Mechanisms Of Alzheimer's Disease; Investigating Therapeutic Interventions For Disease Onset, Alexandra A. Sandberg

Electronic Theses and Dissertations

Alzheimer’s Disease is a multifarious disease that progressively affects more people as both the proportion of older adults in the population and life expectancy increase in both the United States and worldwide. This devastating disease is a result of rampant neuronal loss in the memory centers of the brain that robs the independence of those who are diagnosed and places a heavy burden on those who care for them. Traditionally speaking, research has focused on the hallmark pathology of amyloid plaques, targeting them to try and prevent disease onset. However, countless failures in clinical trials aimed at this said pathology …

Dynamics And Turnover Of Lipid And Protein Domains In Cells And Supported Bilayers, Alan Weisgerber

Electronic Theses and Dissertations

Protein and lipid clustering is an important mechanism for cell processes such as exo- and endo-cytosis and creating functional signaling complexes. It has been seen that both lipids and proteins are involved with the formation of cluster domains on cell membranes, yet little is known about the interplay between the two. In this work I began with visualizing lipid sorting to artificially induced curvature in supported lipid bilayers, with lipid tails affecting the sorting differently to curvature. These results demonstrate that lipids sort to curvature on curved, supported lipid bilayers. The sorting depends on the number of lipids in the …

Antioxidant Biomarkers And Nutraceutical Therapeutics In Neurodegeneration And Neurotrauma, Lilia A. Koza

Electronic Theses and Dissertations

Mild traumatic brain injury (mTBI), yielding a Glascow Coma Scale of 13-15, is the most commonly occurring severity of TBI. Pathology from mTBI consists of blood brain barrier disruption, neuroinflammation, oxidative stress, excitotoxicity, mitochondrial dysfunction, protein aggregation, axonal degeneration, and resulting neuronal death. These processes deplete the body’s endogenous antioxidant system. We report a retrospective analysis of antioxidant blood biomarkers in patients with a history of mTBI from a local sports medicine clinic, Resilience Code. We found persistent sex-specific antioxidant depletions in mTBI patients associated with worsened symptomology.

Certain populations, such as athletes, are at high risk for repetitive mTBI …

Morphological Variation And Community Science In Orthoptera, Amy Byerly

Electronic Theses and Dissertations

Patterns of morphological divergence across species’ ranges provide insight into local adaptation and speciation. Here, we compare phenotypic divergence among 4,221 crickets from 337 populations of two related species of field cricket, Gryllus firmus and G. pennsylvanicus and their hybrids. We find that these species differ across their geographic range in key morphological traits, such as body size and ovipositor length, and we directly compare phenotype with genotype for a subset of crickets demonstrating nuclear genetic introgression, phenotypic intermediacy of hybrids, and essentially unidirectional mitochondrial introgression. We discuss how these morphological traits relate to life history differences between the species. …

Organellar Zn2+ Homeostasis And The Role Of Trpml Channels In Neuronal Lysosome Physiology And Axonal Transport, Taylor Franklin Minckley

Electronic Theses and Dissertations

Zinc (Zn²⁺) is crucial for proper cellular function, and as such it is important to measure and track Zn²⁺ dynamics in living cells. Fluorescent sensors have been used to estimate Zn²⁺ content of subcellular compartments, but little is known about endolysosomal Zn2+ homeostasis. Similarly, although numerous sensors have been reported, it is unclear whether and how Zn²⁺ can be released from intracellular compartments into the cytosol due to a lack of probes that can detect physiological dynamics of cytosolic Zn²⁺. My dissertation started with comparing and characterizing different Zn²⁺ sensors including the …

Mobility Of Older Adults In Mexico City: A Mixed Methods Approach, Jessica Villena Sanchez

Electronic Theses and Dissertations

This dissertation covers the topic of the mobility of older adults in Mexico City using a mixed methods approach. First, I looked at the literature to uncover what is known about elderly mobilities coming from the Global South. Second, I analyzed the 2017 Household Origin Destination Survey to reveal travel behavior patterns and transport mode choice of older adults in Mexico City. Third, I revealed mobility experiences from older adults living in different neighborhoods in Mexico City by conducting twenty two telephone interviews. Lastly, I created joint displays that included both previous results to better understand how the findings from …

Banach Spaces On Topological Ramsey Structures, Cheng-Chih Ko

Electronic Theses and Dissertations

A Banach space T₁(d, θ) with a Tsirelson-type norm is constructed on the top of the topological Ramsey space T₁ defined by Dobrinen and Todorcevic [6]. Finite approximations of the isomorphic subtrees are utilised in constructing the norm. The subspace on each “branch” of the tree is shown to resemble the structure of an ℓ_∞ⁿ⁺¹ -space where the dimension corresponds to the number of terminal nodes on that branch. The Banach space T₁(d, θ) is isomorphic to (∑_n∊ℕ⊕ℓ_∞ⁿ⁺¹)_p , where d ∈ ℕ with d ≥ 2, …

Opportunities And Challenges For Rural Educators: A Mixed Methods Study Of Emergent Bilingual Studies In Rural Colorado, Andrea Johnson

Electronic Theses and Dissertations

Over nine million students in the United States attend school in rural school districts, with a growing percentage of these students identified as emergent bilingual. The purpose of this study is to examine the national emergent bilingual literacy trends and to determine how the opportunities and challenges that rural educators encounter, impact emergent bilingual education in rural schools. Utilizing a theoretical framework of culturally sustaining practices and funds of knowledge, this study uses a convergent mixed methods design to answer the following research questions: What are the national trends in emergent bilingual reading test scores? What opportunities and challenges do …

Twice-Exceptional Identification And Identity Formation: A Mixed Methods Study, Robin Goldin Tobin

Electronic Theses and Dissertations

This research study examined the parent perceptions of and relationships among intellectual potential, academic achievement, and the order of identification of exceptionality for twice-exceptional students. Twice-exceptional students exhibit both giftedness and a learning disability or difference. Consistently and equitably identifying and serving twice-exceptional students is a persistent problem of practice in the field of education (Artiles et al., 2010; Gentry et al., 2019; List & Dykeman, 2019; Moon & Reis, 2004; Webb et al., 2019). This study was supported by a community partner, a private educational testing and advocacy agency in a Western state.

This mixed methods study utilized a …

Topics In Moufang Loops, Riley Britten

Electronic Theses and Dissertations

We will begin by discussing power graphs of Moufang loops. We are able to show that as in groups the directed power graph of a Moufang loop is uniquely determined by the undirected power graph. In the process of proving this result we define the generalized octonion loops, a variety of Moufang loops which behave analogously to the generalized quaternion groups. We proceed to investigate para-F quasigroups, a variety of quasigroups which we show are antilinear over Moufang loops. We briefly depart from the context of Moufang loops to discuss solvability in general loops. We then prove some results on …

Addressing Racial Disparities Through K-12 School-Based Culturally Relevant Interventions, Dina Malala

Electronic Theses and Dissertations

This meta-analysis systematically identified culturally relevant interventions for Black students in K-12 school settings to determine (a) the effect of culturally relevant reading interventions on reading comprehension and reading fluency (b) the effect of culturally relevant behavioral interventions on student behaviors (c) the extent to which culturally relevant interventions impact cultural identity and awareness (d) how cultural identity moderates academic and behavioral outcomes. Twelve studies were identified. Overall, there was a statistically significant combined effect across the twelve studies (g = 0.96, p < 0.05). There was a statistically significant effect of culturally relevant reading interventions on reading outcomes (g =1.174, p < 0.05), a statistically significant effect of culturally relevant behavior interventions on behavior outcomes (g = 0.889, p < 0.05), and a statistically significant effect of cultural identity interventions on cultural awareness and identity (g =0. 914, p < 0.05). The primary limitation of this meta-analysis are the mainstream and standardized dependent variables. Future intervention research is needed that utilizes both culturally relevant independent and dependent variables to better support this population.

Application Of An Organizational Evaluation Capacity Assessment In A Multinational Ngo: A Case Study To Support Applied Practice, Ryan James Smyth

Electronic Theses and Dissertations

As evaluation capacity building (ECB) has rapidly emerged as a practice in human service organizations and as a field of academic inquiry, attention has focused on methods of evaluation capacity building while assessment of organizational evaluation capacity (EC) has lagged behind. To examine the practice of organizational evaluation capacity assessment, this dissertation presents two separate but related studies. In sub-study 1, I present a qualitative evidence synthesis of the research theorizing organizational evaluation capacity models. In sub-study 2, I support the implementation of one of the tools from the evidence-synthesis at a multinational human service organization. I use a concurrent …

Soil Resilience And Arbuscular Mycorrhizal Fungi: How Fungi Can Inform Climate Change Mitigation And Adaptation In Maya Milpa Management, Courtney Mathers

Electronic Theses and Dissertations

In Mexico’s state of Yucatán, climate change impacts like prolonged and less predictable dry season length are manifesting as threats to agricultural production and food security. Nearly two thirds of Yucatán’s population is indigenous, many of whom live in rural communities that rely on rainfed subsistence agriculture (INEGI 2015). Ensuring sufficient food production in the face of climate change relies on the quality of agricultural soils. With both mismanagement of agricultural soils and climate change posing as threats to food production in Mexico, soil management practices that increase a soil quality should be identified and promoted. The primary objective of …

Investigating Spatiotemporal Kinetics, Dynamics, And Mechanism Of Exosome Release, Anarkali Mahmood

Electronic Theses and Dissertations

Exosomes are small lipid-based vesicles that can carry biomolecules from one cell to another. While exosomes are crucial to maintain homeostasis in healthy cells, they are exploited by unhealthy cells to aid disease progression. Exosomes likely facilitate disease progression via the transfer of disease-causing biomolecules from unhealthy to healthy cells. Exosomes are generated in Multivesicular endosomes (MVEs) and are then secreted into the extracellular space to travel to other cells. Despite being a crucial step, very little is known about exosomes release mechanism and dynamics. To further our understanding of exosomes, specifically their secretion, my work has focused on investigating …

Understanding Critical Reflection As A Leadership Development Methodology, Matthew M. Orlowsky

Electronic Theses and Dissertations

How do leaders translate experiences into insights? Critical reflection is offered as a leadership development process that illuminates effective practices following an empirical analysis of 352 United States Air Force Academy cadet essays that describe their most profound leadership experiences. These essays are iteratively analyzed and interpreted using the critical reflection methodology. The essays were examined to find how young leaders turn experiences into leadership insights. The study takes advantage of the distinctive Academy leadership development context and the data available from cadets’ essays describing their profound leadership experiences. There are three contributions bounded in this dissertation and multiple avenues …

Phosphatidylserine Externalization On Non-Apoptotic Cells And Lipid Scramblases In C. Elegans, Julia Frondoni

Electronic Theses and Dissertations

Cell corpse clearance is key for animals to avoid inflammation and autoimmune disease. To better understand the “eat me” signal of phosphatidylserine (PS) exposure for non-apoptotic corpse clearance, we attempted to disrupt the externalization of PS on C. elegans polar bodies. The second polar body undergoes a non-apoptotic form of cell death, loses membrane integrity, externalizes PS and is cleared by embryonic cells during early development. During apoptotic and necrotic cell death, PS asymmetry is disrupted by lipid scramblases, which translocate phospholipids between the leaflets of the lipid bilayer. We found neither apoptotic nor necrotic scramblases are required for PS …

Development And Initial Validation Of An Acculturation Measure For Arab Expatriates In Qatar Using Mixed Methods, Sara Ali Ahmed Zikri

Electronic Theses and Dissertations

Prior research on acculturation has predominantly focused on specific immigrant and ethnic groups in the United States, Europe, and Asia, and there is a lack of publicly available scales that measure acculturation among expatriates in countries of the Gulf Cooperation Council. The purpose of this study was to use a mixed methods research design to develop a theoretical framework of acculturation for white-collar Arab expatriates in Qatar as well as a culturally appropriate self-report acculturation measure. The acculturation stories and experiences of white-collar Arab expatriates in Qatar were qualitatively explored and analyzed, and their findings were used to construct an …

Serially Concatenated Continuous Phase Modulation With Sova Turbo Decoding, Zhijie Guo

Electronic Theses and Dissertations

For a Serially Concatenated Continuous Phase Modulation (SCCPM) system that concatenates a rate of 1/2 Convolutional Code (CC) and an M-ary full response continuous phase modulation (CPM) signal, we design a turbo decoding scheme using the Soft Output Viterbi algorithm (SOVA) and study the system performance. A decomposition model is used in CPM to reduce the number of states and separate the continuous phase encoder (CPE) with the modulator. As a soft-input soft-output (SISO) decoding algorithm, SOVA is used to generate and update the soft information of decoded signal symbols during the iterative process for both the CPM signal and …

Hot Melt Extrusion (Hme) And Amorphous Solid Dispersions (Asds) Strategies For Poorly Water-Soluble Drugs, Zhiqing Hu

Electronic Theses and Dissertations

Amorphous solid dispersion (ASD) has been well known as a potential strategy to improve the bioavailability and dissolution performance of poorly water-soluble drugs. The primary concern of this approach is the long-term stability of the amorphous drug in the solid dispersion. Accurate prediction and detection of the solubility and miscibility of drugs in polymeric binary systems will be a milestone in the development of ASDs. In Chapter Ⅰ, a method based on Flory-Huggins (F-H) theory was proposed to predict and calculate the solubility and miscibility of the drug in the polymeric matrix and construct the phase diagram to identify the …

Curriculum Development Of Agricultural Educators In South Dakota, Mercedes Lemke

Electronic Theses and Dissertations

Curriculum development is an essential component of teaching. Understanding how agriculture education teachers utilize, develop, and adapt content to curriculum can benefit teachers to spend less time on curriculum development. Recognizing the way agriculture education teachers use content in curriculum implementation will allow curriculum developers to create materials that can effectively be used by teachers. This study also looked at the affects of how COVID19 pandemic affected the way teachers locate and develop curriculum. The purpose of this study was to evaluate the way agriculture education instructor’s usage of content for curriculum development, implementation decisions and the affects of the …