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Regression Mixture Models: An Investigation Of The Effects Of Mixing Weights And Predictor Distributions, Phillip Sherlock

Theses and Dissertations

This study focused on understanding how several data characteristics associated with the investigation of effect heterogeneity (i.e., mixing weights, predictor distributions, and the inclusion of covariates) affected enumeration and parameter recovery with regression mixture models. The inclusion of C on X paths, where the latent class, C, is regressed on the predictor, X, allows predictor means to vary across classes, at two points in the model building process—during and after enumeration—was of interest. This main aim was accomplished by comparing the correct enumeration rates and parameter coverage rates with and without freely estimated predictor means across classes for models with …

Risk And Resistance Factors For Depression And Anxiety Among Youth With Sickle Cell Disease, Laura Reinman

Theses and Dissertations

Objective: Depression and anxiety are common problems for adolescents with sickle cell disease (SCD). It is important to understand both risk and resiliency factors contributing to psychological outcomes among youth with SCD in order to prevent and effectively treat such problems. To better elucidate contributing factors to depression and anxiety among youth with SCD selected risk and resiliency factors from the risk-and-resistance model adapted for SCD were examined (Barakat, Lash, Lutz, & Nicolaou, 2006). The risk factor of fatigue and resistance/resiliency factors of cognitive appraisal of stress and self-concept are of focus because they have been understudied, and their temporal …

Disparities In Non-Small Cell Lung Cancer In The United States: An Examination Of Treatment, Survival, And Access To Care, Cassie Lewis Odahowski

Theses and Dissertations

Lung cancer is the leading cause of cancer-related deaths in the United States with a 5-year survival rate of only 18%. Differences in access to care and treatment utilization may play a role in observed survival disparities among rural patient populations. This dissertation aimed to examine rural disparities in all-cause and lung-cancer specific survival, time to treatment initiation, and utilization of surgical treatment among non-small cell lung cancer cases.

We utilized comprehensive cancer registry data from the Surveillance, Epidemiology, and End Results program linked with Medicare billing claims (SEER-Medicare) for non-small cell lung cancer (NSCLC) patients diagnosed between 2003-2011. We …

Role Of Epigenetic, Molecular And Cellular Pathways In The Regulation Of Inflammation, William James Becker

Theses and Dissertations

Dysregulated inflammation is at the heart of countless human diseases. Graft rejection is the process by which an organ from an incompatible donor is rejected by the recipient whose immune cells attack the foreign tissue. Colitis is an inflammatory disorder caused by undue chronic inflammation in the colon and rectum that can progress to cancer. Colitis incidence is on the rise, especially in developing nations and Asia; and the list of patients who need organ transplants grow by the day. Therapies for both graft rejection and colitis are limited to immunosuppressive drugs that leaves patients vulnerable to infection, heart disease, …

Proteomic And Genomic Evolution Of Phicbkviruses, Kiesha Wilson

Theses and Dissertations

It is estimated that there are 10³¹ phages in the global population. They continue to maintain their populations by undergoing 10²⁴ infections per second. Every time these phages replicate, there is potential for genetic exchange and mutations. Because of this potential, it has been assumed that phage evolution is heavily influenced by mosaicism. However, it is now clear that phage evolution varies by host type and phage type. Here, we use genomic and proteomic analyses to study the evolution of phages that infect Caulobacter crescentus. The study began by comparing six bacteriophage genomes that were larger than …

Regulation Of Arabidopsis Floral Organ Development By The Transcription Factor Aintegumenta-Like6, Jorman Heflin

Theses and Dissertations

Flowers, and the fruits and seeds they produce, are of great agricultural and economic importance. Understanding the molecular mechanisms that mediate the identity, size and arrangement of floral organs within the flower may allow us to tune these elements for increased crop productivity. I examine several potential regulatory targets of the Arabidopsis AINTEGUMENTA-LIKE6 (AIL6) transcription factor that is involved in these processes and I identify protein-protein interactions that may mediate its activity in flowers. As described by the ABCE model, unique floral organ identities are specified in each whorl of the flower by different combinations of homeotic gene activities. Two …

Investigation Of Energy-Related Wastewater Impacts On Disinfection By-Product Formation In Drinking Water, Hannah K. Liberatore

Theses and Dissertations

Elevated bromide and iodide in drinking water sources contribute to the formation of toxic brominated and iodinated disinfection by-products (DBPs) during drinking water treatment. Energy extraction and utilization processes, including hydraulic fracturing (HF) and coal-fired power plants (CFPPs), produce wastewaters with bromide/iodide levels on the order of tens to thousands of mg/L. These wastes have the potential to impact drinking water sources through both intentional (e.g., direct discharge) and accidental (e.g., basin overflow, spill) release pathways. This research focuses on a combination of quantitative and non-targeted approaches to assess DBP formation impacts from HF and CFPP wastewaters, with complementary toxicity …

Pre-Exposure Prophylaxis (Prep) For Hiv Prevention: A Mixed-Methods Study Of Sexual Risks And Knowledge, Perceptions, And Willingness Of Prep Use Among African American Women In The South, Jamie Troutman

Theses and Dissertations

There are approximately 1.1 million people living with HIV in United States, with nearly 40,000 new diagnoses annually. Significant regional and racial disparities are associated with HIV diagnoses — with the South experiencing the greatest burden of HIV and African American women accounting for 60% of new diagnoses among women. Pre-exposure prophylaxis (PrEP) has been designated as an effective tool to prevent HIV transmission among individuals who may be at risk of HIV infection. Earlier PrEP research has focused mainly on at-risk groups such as men who have sex with men (MSM). Previous PrEP research involving African American women included …

Energetic Consequences Of Human Impacts For Bioindicator Atlantic Ghost Crab (Ocypode Quadrata), Mustafa Remzi Gül

Theses and Dissertations

Human activities have caused notable changes in ecosystems globally over the past century, which cause substantial ecological issues. The degree of these ecological issues is often investigated using the responses of bioindicator species. Bioindicator species often reduce their population densities and individual sizes as a response to the human disturbance. Observing these variations in the demographics is often an effective way to measure the strength of the ecological changes. However, they do not provide any mechanistic reason (s) for the shifts in the demographics, which is important for making predictions about responses of the species to the future conditions. Therefore, …

Flame Spray Pyrolysis Of Ce-Mn Solid Solutions For Catalytic Applications, Nicole Cordonnier

Theses and Dissertations

Flame spray pyrolysis (FSP) is a method of quickly synthesizing active particles in a flame. Precursors are dissolved in a flammable organic solvent before being sprayed into the flame environment where they rapidly burn. Particle formation occurs on the order of 10 milliseconds. FSP has been shown to be a viable method of producing materials on an industrial scale, capable of producing grams of particles per minute. Metastable structures which exist in the liquid phase, but are difficult to synthesize using traditional impregnation methods can be formed with FSP due to fast quenching times. For example, solid solutions of Ce-Zr …

Epigenetic And Purinergic Regulation Of Mast Cells Mediator Release, Zahraa Abdulmohsin Mohammed

Theses and Dissertations

Mast cells (MCs) are well known for their implications in allergic reactions. They are also known to have multiple functions in the innate and adaptive immune system. Their activation plays an essential role in many aspects of physiological and pathological conditions. Allergies are considered chronic conditions that affect more than 60 million people in the U.S. These diseases are driven by the activation of MCs in response to IgE-mediated antigen, rendering these cells as targets for the management of allergies and asthma. Therefore, this research considers the understanding of their activation and the regulation of their response to be an …

The Effects Of Climate Change On The Ecotoxicology Of Contaminants Of Emerging Concern: Flame Retardants, Contemporary Use Pesticides And Pharmaceuticals Personal Care Products On The Estuarine Grass Shrimp, Palaemontes Pugio, Rajaa Nouri Al-Yassein

Theses and Dissertations

Global Climate Change may adversely affect the environment, increasing water temperature and altered salinity which may affect the toxicity of both legacy pollutants and Contaminants of Emerging Concern (CECs). Acute, 96 hour toxicity tests with adult grass shrimp (Palaemonetes pugio) assessed the effects of CECs (Polybrominated Diphenyl Esther (PBDE) – 47, ibuprofen, bifenthrin, triclosan, and bifenthrin/triclosan mixtures) under Standard Conditions (20°C, 20psu) and different Climate Change Conditions (30°C, and/or35psu) In addition, the grass shrimp microbiome (e.g. Vibrio bacteria) were assessed following acute triclosan exposures at the Maximum Exposure Concentration (MECs) and Minimum Inhibitory Concentration (MICs) under standard conditions. …

Potassium Fertilization Effects On Yield For Wheat, Soybean, And Corn Grown In Coastal Plain Soils, Renada Davis

Theses and Dissertations

A study conducted on wheat, soybean, and corn crops was designed to assess the effect of potassium fertilization based on current potassium (K) fertilizer recommendations on crop yield, soil K levels, and plant tissue K concentration. The objectives of this study were to 1) evaluate the effect K fertilization has on crop yield; 2) To assess soil K levels through the duration of the experiment and the effect fertilization may have on soil K levels; and 3) to evaluate the effect of fertilization on plant tissue K concentrations. There was no statistical difference in yields between plots treated with the …

Machine Learning Methods For Rapid Inspection Of Automated Fiber Placement Manufactured Composite Structures, Christopher Sacco

Theses and Dissertations

The advanced manufacturing capabilities provided through the automated fiber placement (AFP) system has allowed for faster layup time and more consistent production across a number of different geometries. This contributes to the modern production of large composite structures and the widespread adaptation of composites in industry in general and aerospace in particular. However, the automation introduced in this process increases the difficulty of quality assurance efforts and inspection. The AFP process can induce a number of manufacturing defects including wrinkles, twists, gaps, and overlaps. The manual identification of these defects is often laborious and requires a measure of expert knowledge. …

Elaborative Rehearsal: An Examination Of Usage, Perceptions Of Utility, And Differences In Metacognition And Test Performance, Tori Kim Norris

Theses and Dissertations

This action research study explored the use of elaborative rehearsal as an intervention and examined differences in metacognition and test performance among college students in a general psychology course. Metacognitive processes are crucial for adequate comprehension. Students often come into college having very little metacognition, knowledge about different strategies, different cognitive tasks, and sometimes even accurate knowledge about how they learn (Pintrich, 2002). Common metacognition strategies are note-taking, summarizing, finding main ideas, writing to learn, self-questioning, outlining, previewing, reflecting, reciting and reviewing (Kisac & Budak, 2014). Elaborative rehearsal is a metacognitive learning strategy that encompasses many of these components. Unfortunately, …

Experimental Methods And Techniques For Improved Biomechanical Characterization Of Diverse Murine Aortopathies, Brooks Alexander Lane

Theses and Dissertations

Aortopathies constitute a broad class of diseases affecting the aorta – the largest artery responsible for distributing oxygenated blood to the systemic circulation. Specifically, aortic aneurysms (AAs) are described as a focal dilation of the vascular wall exceeding 50% of the normal vessel diameter. Ultimately AAs may stabilize, dissect, or rupture, with the latter virtually ensuring mortality. Currently clinicians consider prophylactic intervention based on size and growth-rate criteria that have been estimated from large-cohort statistical analyses. These criteria, however, fail to address the underlying mechanisms. Furthermore, 13% of small-to-mid sized AAs have been found to rupture prior to meeting these …

Between Holy Russia And A Monkey: Darwin's Russian Literary And Philosophical Critics, Brendan G. Mooney

Theses and Dissertations

This dissertation is dedicated to the response of nineteenth-century Russian writers to the English naturalist Charles Darwin’s theory of evolution by natural selection. His theory was by no means the next discovery in a series of indistinguishable scientific discoveries; the fact that its implications touched every aspect of human social life was lost on no one, despite the fact that Darwin did not discuss human evolution in any detail. The Origin changed what it meant to be human: what Darwin’s readers took to be their place in the universe and how they ought to act with regard to both other …

Evaluating Impacts Of A Multilevel Resilience-Based Psychosocial Intervention On Mental Health Of Children Affected By Parental Hiv In China, Yanping Jiang

Theses and Dissertations

Background: Children affected by parental HIV are commonly exposed to multiple risk factors, including parental illness and death, other traumatic life events, HIV stigma, and poverty, all of which in turn put them at elevated risk of experiencing poor mental health outcomes. Previous research has suggested the promise of psychosocial interventions in improving mental health for children affected by parental HIV through an integrated and multilevel resilience-based approach. However, there are few multilevel resilience-based interventions for this group, and the efficacy of such interventions on mental health outcomes has not been fully examined. Furthermore, very few studies have examined whether …

Fostering Agency In Single-Gender, Middle Level Ela Classrooms: A Descriptive Multiple-Case Study, Jennifer V. Stowe

Theses and Dissertations

Students’ sense of agency or self-efficacy has been linked to student achievement levels (Goodman & Eren, 2013; Johnston, 2004; Skinner, Wellborne, & Connell, 1990). Research has also established that teachers position their students as having agency in the context of the classroom, frequently by the ways that they use language (Johnston, 2004; Paulson & Theado, 2014). However, little, if any, extant research describes teacher language as it relates to agency within the middle level English Language Arts (ELA) classroom. Additionally, studies concerning agency rarely address the ways in which gender may influence the ways in which teachers position their students …

The Influence Of Adhd Symptoms And Social Functioning On Anxiety And Depression Symptoms In College Students, Danielle Willis

Theses and Dissertations

Previous research has shown that Attention-Deficit/Hyperactivity Disorder (ADHD) is associated with impaired social functioning in children and adolescents. ADHD and poor social functioning have been shown to be separately associated with increased anxiety and depression symptoms as well. However, little research has examined these associations among college students. College is a transitional period of increased stress and exposure to new social situations for all students, but may be even more challenging for those with ADHD, who are already at risk for increased internalizing problems and impairment in social functioning. The current study aimed to examine the influence of ADHD symptoms …

The Impact Of Mindfulness Practices On The Dispositions Of Eight Third-Grade Elementary Students At An Elementary School In The Southeast Region Of The United States, Jakob Lauffer

Theses and Dissertations

The purpose of the study was to examine the impact mindfulness sessions had on the dispositions of eight third-grade students. In the Spring of 2019, mindfulness practices were presented to third-graders in their regular classroom setting every Monday and Thursday over the six-week qualitative action research study. During this time, the teacher-researcher administered 15-minute mindful lessons that aimed to help increase coping strategies in the student population. The instruments used for data collection in this qualitative action research study were: a pre/post-intervention questionnaire, weekly exit slips utilizing multiple choice and open-ended questions, field notes, and digital video recordings. Students utilized …

The Persistent Maladaptation Of Pieris Macdunnoughii: Constraints On Adaptation To An Evolutionary Trap, Rachel A. Steward

Theses and Dissertations

Evolutionary traps arise when organisms use novel, low-quality or even lethal resources based on previously reliable cues. Persistence of such maladaptive interactions depends not only on how individuals locate important resources, such as host plants, but also the mechanisms underlying poor performance. Pieris macdunnoughii (Remington) (Lepidoptera: Pieridae) lays eggs on a non-native mustard, Thlaspi arvense (L.) (Brassicaceae), which is lethal to its larvae. However, in the 150 years since T. arvense invaded this butterfly continues to recognize and oviposit on the invasive mustard.

I evaluated two possible constraints on the evolution of decreased preference within an invaded population. First, an …

Short Term Shifts In Soil Nematode Food Feb Structure And Nutrient Cycling Following Sustainable Soil Management In A California Vineyard, Holly M. Deniston-Sheets

Master's Theses

Evaluating soil health using bioindicator organisms has been suggested as a method of analyzing the long-term sustainability of agricultural management practices. The main objective of this study was to determine the effects of vineyard management strategies on soil food web structure and function, using nematodes as bioindicators by calculating established nematode ecological indices. Three field trials were conducted in a commercial Pinot Noir vineyard in San Luis Obispo, California; the effects of (i) fertilizer type (organic and inorganic), (ii) weed management (herbicide and tillage), and (iii) cover crops (high or low water requirements) on nematode community structure, soil nutrient content, …

Gen-Z Ambassadors: Students Supporting Persons With Alzheimer’S Disease And Their Caregivers In The Rio Grande Valley, Sofia G. Homes, Samantha R. Woo, Ashley G. Caldera, Sergio N. Gonzalez-Eymard, Rosa V. Pirela, Francisco Fernandez, Gladys E. Maestre

School of Medicine Publications

Background: Youth participation in policy, research, education and community development initiatives is a right embedded in the United Nations Convention on the Rights of the Child (UNCRC, General Assembly, 1989). However, avenues for youth participation in health promotion and care remains limited. Our Ambassadors program prepares high-school students on the Texas-Mexico border to understand and empathize with persons with Alzheimer’s disease (PwAD) and to empower their family and caregivers, consummating the UNCRC in the service of transformative community change actions.

Methods: Our long-term objective is youth participation, defined as practices that involve collaboration between students and various community stakeholders …

Improving Attention And Emotional Regulation For Middle School Students Through The Use Of Mindfulness Practices, Sean Mattner

School of Education and Leadership Student Capstone Projects

Mattner, S. Improving Attention and Emotional Regulation for Middle School Students Through the Use of Mindfulness Practices. (2019) Research has demonstrated that establishing a mindfulness practice has a range of mental, emotional, social, and educational benefits. The curriculum designed for this project focuses on using mindfulness techniques for 6th-8th grade students to improve attention, concentration, and emotional regulation. Mindfulness practices have been implemented in a number of settings, from hospitals to work environments for decades, but implementing it within the classroom, especially for children, is limited. The project involved creating a diverse curriculum that engages students with mindfulness through activities …

The Reduction Of Stormwater Runoff Pollution Through Community Service Efforts, Dana Damm

School of Education and Leadership Student Capstone Projects

Damm, D. The Reduction of Stormwater Runoff Pollution Through Community Service Efforts (2019) This capstone project creates a curriculum unit for 8th grade Earth Science students. It utilizes traditional instructional techniques to convey standards-based information and then it elaborates in more detail using hands-on laboratory experiences, modeling and community service work. The goal of this project is to educate students about the water cycle, watersheds, city utilities and the value of community service. Students will work with local residents to adopt storm drains and maintain them in order to prevent runoff pollution from entering the watershed. By encouraging students to …

Increasing The Participation And Success Of Struggling Students In High School Physics Courses, Ian O'Neill

School of Education and Leadership Student Capstone Projects

O’Neill, I. Increasing the Participation and Success of Struggling Students in High School Physics Courses (2019) Physics is the most mathematically complex science course offered in the high school setting. Due to the higher level of mathematical proficiency needed to succeed in physics, it is common for school districts to place it as the final science course offered to high school students. Minnesota only requires students to take three years of science in order to graduate and has no specific requirement for physics. This has led to low enrollment and the negative stigma that physics is an unnecessary and difficult …

The Lost Boys: An Exploration Of The Male Gender Gap And Its Causes, Derek Swart

School of Education and Leadership Student Capstone Projects

The male gender gap refers to a discrepancy between achievement and investment levels of male and female students. Demonstrated through a variety of metrics such as graduation rates, grade point average, enrollment in Advanced Placement courses, special education identification, and behavioral intervention, male students demonstrate lower levels of academic success than female students. Factors influencing this gap appear to include social factors such as male disinclination to orient peer relationships around academic topics, internal factors such as lower measured time spent on study or homework in males, and different academic expectations for males and females from their teachers. This project …

How Place-Based Education Increases Student Interpretation Of Minnesota's Landscape And Geologic Processes, Jessica Strom

School of Education and Leadership Student Capstone Projects

Gaining perspective on one’s surroundings comes in many ways. One method to connect students to their local area and help them develop a sense of place is through place-based education. Making scientific-based observations and interpretations of a physical landscape and also interviewing community members can help students build an understanding of an area’s past and can help students make better educated decisions about how to take care of an area in the future. This capstone paper and curriculum unit project addressed the topic of how place-based education increases student interpretation of Minnesota's landscape and geologic processes. Place-based education is a …

Amending Flex Time: A Proposal, Johnathan Thompson

School of Education and Leadership Student Capstone Projects

The Minnesota high school where I am employed has recently instituted a program called Flex Time. This program is a one-hour break in the middle of the day and could be equated to a recess. One of the stated purposes of this program is to assist students in developing their social and emotional competencies. This purpose has prompted the creation of this capstone which answers the question, How can Flex Time be constructed to ensure that it is best assisting all students in developing their individual social and emotional competencies? In answering the question, I discovered and explored the five …