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Exploring The Genomic Basis Of Traits Relevant To Evolution And Ecology Of Chestnuts (Castanea) Using High-Throughput Dna Sequencing And Bioinformatics., Nicholas R. Labonte

Open Access Dissertations

Introduced pests and pathogens have devastated forest ecosystems in the temperate zone; in eastern North America, introduced pests and pathogens have led to the elimination of most mature elms (Ulmus), ashes (Fraxinus), hemlocks (Tsuga) and chestnuts (Castanea) over large areas where these genera were formerly abundant and important for local ecosystems. The restoration of species affected by introduced pests and pathogens requires the development and propagation of trees that possess heritable resistance. High-throughput DNA sequencing and genomics provide opportunities for researchers to identify resistance gene candidates, screen germplasm, and develop markers for marker-assisted selection in breeding programs, with the goal …

Teachers' Perceptions Of The Impact Of Culturally Responsive Pedagogy On The Student Learning Outcomes Of African American Male Students., Dennisha M. Murff

Open Access Dissertations

The purpose of this qualitative study was to explore teachers’ perceptions of the impact of implementing culturally responsive pedagogical practices on the student learning outcomes of African-American male students. The secondary purpose was to identify teachers’ perceptions of the culturally responsive pedagogy strategies needed in the classroom to address the diverse needs of African-American male students. The case study approach allowed for additional insight into the potential impact of culturally responsive pedagogical practices on the student learning outcomes of African-American male students in the elementary school setting. Data were collected from a large, diverse elementary school in an urban school …

Effect Of Feed Additive Enzymes On Growth Performance And Immunological Response In Growing Pigs And Poultry, Emily R. Otto-Tice

Open Access Dissertations

As demand for oilseeds and grains increase for uses beyond livestock feeds, swine and poultry producers are continually challenged to source alternative feed ingredients or co-products that are traditionally fed to ruminant animals. Many of these alternative feed ingredients have characteristics, such as higher fiber content or inherent antinutritional factors, that may reduce the feeding value for swine and poultry. To help improve the nutrient availability as well as understanding the positive affect that feeding fiber can have on gut health, biotech companies have developed novel enzymes to help breakdown these complex carbohydrate structures to release additional energy or reduce …

Determining Variation In Virulence, Persistence, And Stress Tolerance Among Salmonella Enterica And Listeria Monocytogenes From Food And Food-Associated Environments, Andrea J. (Ray) Etter

Open Access Dissertations

The U.S. food industry employs multiple strategies to prevent foodborne illness including the use of antimicrobials, sanitizers, and heat to reduce or eliminate pathogens in food products. However, Listeria monocytogenes and Salmonella enterica isolates have widely varying tolerance to common processing stresses. Additionally, both pathogens display considerable variation in virulence among serovars and strains. The goal of these studies was to characterize the range of virulence and persistence capabilities for L. monocytogenes and S. enterica isolates. To this end, we determined the prevalence of inlA mutations in L. monocytogenes collected from retail deli surfaces, and used PFGE to study the …

Associative Learning Of The Generalist Predator Podisus Maculiventris To Herbivore- Induced Plant Volatiles, Ulianova Vidal-Gómez

Open Access Dissertations

Following herbivore attack, plants produce volatile organic compounds (HIPVs for herbivore induced plant volatiles) that allow predators to find and consume herbivores. The generalist predator Podisus maculiventris likely uses HIPVs in its foraging decisions. I hypothesized that the behavioral responses of this predator to HIPVs are acquired via associative learning, as suggested by theoretical predictions linking natural enemy host range with odor preferences. To evaluate P. maculiventris learning capabilities across different levels of biological organization, I use the tri-trophic system consisting of tomato (Solanum lycopersicum), hornworm caterpillars (Manduca sexta), and the predaceous stinkbug Podisus maculiventris to answer the following questions: …

From Crypt Depths To Carbon Dioxide Equivalents: Characterizing The Interactions Between Swine Nutrition, Health And The Environment, Caitlin Vonderohe

Open Access Dissertations

There are many ways to measure the relative success and sustainability of a swine production system. The most economically relevant measures are growth performance and feed conversion. However, other measures such as greenhouse gas emissions, nutrient excretion, health and degree of intestinal inflammation can also be significant reflections of the interaction between nutrition, genetics and environment. Three experiments were conducted to characterize how swine nutrition and management affect the environmental footprint of swine production. The objective of experiment 1 was to determine the effect of reducing dietary crude protein and supplementing synthetic amino acids on growth performance, greenhouse gas emissions …

Investigation Of Interaction Between Peptide And Lipid Bilayer By Molecular Dynamics Simulation, Ning Xiang

Open Access Dissertations

Antimicrobial peptides (AMPs) inactivate microbial cells through pore formation in cell membrane. Because of their different mode of action compared to antibiotics, AMPs can be effectively used to combat drug resistant bacteria in human health. AMPs can also be used to replace antibiotics in animal feed and immobilized on food packaging films. We developed a methodology based on mechanistic evaluation of peptide-lipid bilayer interaction to identify AMPs from soy protein. Production of AMPs from soy protein is an attractive, cost-saving alternative for commercial consideration, because soy protein is an abundant and common protein resource. This methodology is also applicable for …

A New Transduction Mechanism For Detecting Biological Radiation Damage Using Metabolic Response Of Yeast As A Surrogate Marker, Chang Keun Yoon

Open Access Dissertations

Radiation was a serendipitous discovery in the late 19th century and since then has been an effective tool utilized in many different fields such as energy, weaponry, medical diagnosis/treatment, food sterilization, and archaeological. As its demand increased in multiple areas, it became necessary to control it more precisely and cautiously, and so began the accelerated development of radiation detectors. Such radiation sensors (or dosimeters) have existed since the beginning of the 20th century in various forms. Most radiation dosimeters in use today are targeted for healthcare and industrial workers who work around high levels of radiation (e.g., hospital personnel and …

Cadmium Explains, In Part, The Cardiovascular Toxicity Of Cigarette Smoking, Eric M. Hecht

Open Access Dissertations

Cigarette smoking is a well-known cardiovascular risk factor associated with an estimated 311 premature cardiovascular deaths per 100,000 smokers in the United States each year. The mechanism of arterial damage due to tobacco smoke is not fully elucidated. One plausible theory suggests that toxic exposure to one or more chemical constituents found in tobacco smoke causes persistent inflammatory changes at the level of the endothelial cell, which leads to arterial damage and atherosclerosis. The toxic elements found in tobacco smoke currently thought to be most responsible for cardiovascular toxicity include nicotine, carbon monoxide (CO), oxidant gases, polycyclic aromatic hydrocarbons (PAHs), …

Mitochondrial Dna (Mtdna) Variant-Nuclear Dna Variant Interactions And Gene-Dietary Exposure Interactions In Age-Related Macular Degeneration (Amd), Patrice J. Persad

Open Access Dissertations

Age-related macular degeneration (AMD) is shaped by genetic and non-genetic factors. Examining such factors—along with interactions between these factors—that contribute to AMD is crucial because permanent vision loss can arise, and better understanding the disease pathogenesis will foster potential treatments. Consideration of gene-gene and gene-environment interactions may identify additional risk factors and explain some of the variability in disease presentation and progression. Several studies have revealed associations between AMD risk and mitochondrial (mt) variants [mt single nucleotide polymorphisms (SNPs)]; additionally, mtDNA damage or mt dysfunction in retinal pigment epithelium (RPE) cells can affect AMD-related processes. Overall diet quality has been …

Assessing Actions And Feelings Related To Multidimensional Well-Being: Validation Of The I Coppe Actions And Feelings Scales, Carolyn L. Rubenstein

Open Access Dissertations

The purpose of this study was to validate two new scales on actions and feelings for well-being in key areas of life. The I COPPE Actions Scale and the I COPPE Feelings Scale measure Interpersonal, Community, Occupational, Physical, Psychological, and Economic (I COPPE) well-being. A total of 478 University of Miami employees provided online responses to the I COPPE Actions and Feelings Scales. Confirmatory factor analysis was used to examine the a priori hypothesized correlated six-factor structure for responses to the I COPPE Actions and Feelings Scales. Multiple group confirmatory factor analysis was used to evaluate measurement invariance across gender …

Transport Properties In Porcine Meniscus Fibrocartilage, Kelsey L. Kleinhans

Open Access Dissertations

The knee meniscus is a complex structure that has been the focus of important and extensive research for many years. The most common areas of study include meniscal structure, meniscal tears, regeneration, and the biomechanical and anatomical forces endured by the meniscus. Although much research has been done regarding these tissues, more is needed in order to fully understand the role that menisci plays in the function and pathophysiology of the human knee. The fibrocartilaginous meniscus plays an essential role in distributing the majority of the load and maintaining not only congruency, but also lubrication in the knee joint. Degeneration …

The Impact Of Intrathecal Baclofen On Growth Among Children With Spasticity Ages 2-20 Years, Amy Lynn Malmsberry Kaye

Open Access Dissertations

Spasticity is present in 80% of children experiencing Cerebral Palsy (CP) and 50% of those having sustained a Traumatic Brain Injury (TBI) (Tilton, 2015; O'Shea, 2008). Growth impairment among children with motor disabilities secondary to a Central Nervous System (CNS) insult is common and interferes with mobility, functioning comfort, and Quality of Life (QOL) (Vles, 2011; Mallarkey, 2009; Krick, Murphy-Miller, Zeger, & Wright, 1996). Spasticity may range fro mild to severe involving any body part (Mallarkey, 2009). There are a broad range of treatment modalities for managing spasticity impacting the child, parent or caregiver, and a multidisciplinary healthcare team (Brashear …

The Ontogeny Of Duets In A Neotropical Bird, The Canebrake Wren, Karla D. Rivera Cáceres

Open Access Dissertations

Interactions in which individuals exchange vocal signals are an important aspect of communication in many species. Human conversation provides one familiar example. Other examples drawn from songbirds are countersinging between territorial males and duetting between mated males and females. The development of vocal signals such as human speech and the song of songbirds has been amply studied, but, we know significantly less about the development of the rules that mediate vocal interactions in these groups. Because of the interactive nature of duets, duetting species provide an ideal model system to study the development of vocal interaction rules. Duets involve specific …

Body Weight, Nutrition, And The Classical Singer: A Review Of The Existing Literature, Rebekah Kaye Smeltzer

Open Access Dissertations

The discussion of body weight and the classical singer is not new, but recent events, such as HD broadcasts of opera productions, along with rising obesity rates across the general populace, have led to increased debate surrounding the stereotype of the overweight opera singer. As overweight singers face increased pressure to lose weight, a variety of suggestions have traveled through the vocal community, but little evidence-based research or health care advice has been readily available. Research has been conducted which seeks to answer how obesity affects vocal function, as well as how bariatric surgery may affect the voice; however, this …

Three Essays In Financial Economics, Da Ke

Open Access Dissertations

My dissertation examines economic determinants of household financial decisions and investor behaviors. It contains three essays. The first essay investigates whether gender norms shape intra-household financial decision making. Analyzing microdata covering more than 30 million U.S. households, I document that families with a financially sophisticated husband are more likely to participate in the stock market than those with a wife of equal financial sophistication. Consistent with the gender norm hypothesis, the baseline effect is attenuated among individuals brought up by working mothers, but becomes stronger among descendants of pre-industrial societies in which women specialized in activities within the home and …

Spatial Control Of Cell Polarity And Cell Growth By Conserved Ndr Kinase Orb6, Illyce Nunez

Open Access Dissertations

During many cellular processes, such as cell morphogenesis, migration, and asymmetric cell division, eukaryotic cells modulate their growth and polarity. Understanding the molecular mechanisms that govern polarized cell growth has the potential to reveal important insights into diseases such as neurodegeneration, heart disease, and cancer. The model organism fission yeast Schizosaccharomyces pombe, with its cylindrical shape and bipolar growth zones, enables straightforward evaluation of changes in growth and polarity upon genetic or pharmacological manipulation. In addition, S. pombe has a characteristic response to nutrient starvation, which causes cells to alter their morphology by dividing at a shorter cell length and …

The Pre-Collegiate Pipeline To Diversify The Nursing Workforce, Pamela L. Mccue

Open Access Dissertations

In the United States, increasing racial and ethnic diversity coupled with widening health care disparities have prompted growing concern about the lack of racial and ethnic diversity in the health professions. As the largest sector of the health care workforce who practice at all levels and settings of health care, the nursing profession has the potential to widely effect changes to reduce disparities. Yet only 19% of the registered nurse workforce reflects diversity, prompting a look at pre-collegiate pathways to a nursing career. Guided by Social Cognitive Career Theory, this study examined the pre-college factors that influenced student choice in …

Organellar Genome Evolution In Red Algal Parasites: Differences In Adelpho- And Alloparasites, Eric Salomaki

Open Access Dissertations

Parasitism is a common life strategy throughout the eukaryotic tree of life. Many devastating human pathogens, including the causative agents of malaria and toxoplasmosis, have evolved from a photosynthetic ancestor. However, how an organism transitions from a photosynthetic to a parasitic life history strategy remains mostly unknown. Parasites have independently evolved dozens of times throughout the Florideophyceae (Rhodophyta), and often infect close relatives. This framework enables direct comparisons between autotrophs and parasites to investigate the early stages of parasite evolution. Parasitic red algae have traditionally been defined as either ‘adelphoparasites’, which infect hosts within their same family or tribe, or …

Anthelmintic Efficacy Of Bioactive Compounds Within Cranberry Vine And Birdsfoot Trefoil, Carly Barone

Open Access Dissertations

With the growth of resistance to commercial dewormers in small ruminant gastrointestinal nematodes (GIN), alternative methods are needed for GIN control. It has been shown that plants containing certain secondary compounds (SC) suppress GIN infection, but there is a lack of knowledge concerning the mechanism behind this anthelmintic activity, as well as a lack of viable alternatives to commercial dewormers in the northeastern United States. Secondary compounds, such as proanthocyanidin (PAC), have complex chemical structures that vary between plant species, while SC concentrations can vary between different varieties of the same species. The relationship between specific SC and anti-parasitic efficacy …

Exploring Ways To Enhance Teens' Participation In Social Media Interventions: A Formative Research Study, Hailee K. Dunn

Open Access Dissertations

Social networking sites (SNSs) now serve as a primary form of socialization for adolescents. A growing body of research indicates that permissive drinking norms exist on online just as they do offline increasing teens’ risk for underage drinking and other risk behaviors. However, limited research exists on how to address this growing public health problem. The purpose of the present study was to conduct a formative investigation on how to create substance prevention interventions that address adolescents’ exposure to normative displays of substance use on SNSs. Thirty-three adolescents in grades nine through twelve were recruited from various school- and community-based …

Stress, Coping, Emotional Intelligence, Emotional Health And Cortisol In Premature Infants, At Age 23, Joyce Ellen Hickey

Open Access Dissertations

Little is known about the psychobiological processes of adults, at age 23 who were born prematurely. Compared to infants born at term, premature infants face additional obstacles of immature body systems, more neonatal stress and are at risk for developmental delay and possible parental overprotective patterns. The Developmental Origins of Health and Disease theory asserts that early prenatal and neonatal stress disturbs hypothalamic-pituitary-adrenal (HPA) axis function, which in the long run, affects later health and behavior. The purpose of this secondary analysis is to examine neonatal stress of prematurity on coping, emotional intelligence, physiological responses, developmental milestones and emotional health …

Three Essays On The Impact Of Information On Nonpoint Source Polluters' Behavior, Haoran Miao

Open Access Dissertations

Nonpoint source pollution is recognized as the primary cause of water pollution in the United States and has many adverse environmental effects in other areas such as Europe and China. In this dissertation research, I examine the role of information in managing nonpoint source pollution through voluntary programs and regulatory policies. Specifically, I look into the effect of informational nudges, information appealing to people to act, and financial incentives to reduce nonpoint source pollution through behavioral changes. Also, I investigate the impact of information on nonpoint source polluters’ behavior under the ambient-based policy when the environmental uncertainty exists at the …

European American Students' Supports, Challenges, And Perceptions Of Their Peers Of Color, Crystal Nicole Gayle

Open Access Dissertations

The purpose of the present study was to examine the experiences of European American students as they obtain advanced degrees in psychology. The study investigated what European American students find supportive and unsupportive as they pursue their doctoral degrees. The participants of this study consisted of 12 graduate students. Qualitative methods were employed, and data obtained through semi-structured interviews was analyzed using content analysis. The interviews revealed factors that students believe have facilitated their success in graduate school, as well as challenges experienced during graduate school, and the types of strategies they used when faced with obstacles. The participants were …

Annual Forage Cropping-Systems For Midwestern Ruminant Livestock Production, John Ernest Mcmillan

Open Access Dissertations

Annual forage cropping systems are a vital aspect of livestock forage production. One area where this production system can be enhanced is the integration of novel annual forages into conventional cropping systems. Two separate projects were conducted to investigate alternative forage options in annual forage production. In the first discussed research trial, two sets of crops were sown following soft red winter wheat (Triticum aestivum L.) grain harvest, at two nitrogen application rates 56 and 112 kg ha-1 . The first set of crops were C4 summer annuals seeded within two weeks of wheat grain harvest and included, brown …

Impact Of Dietary Modification On Aflatoxicosis In Poultry, Xi Chen

Open Access Dissertations

Aflatoxin contamination in feed and feed ingredients is of high worldwide prevalence, posing serious risks to the livestock industry. A series of studies were conducted to better understand the comprehensive impact of aflatoxicosis and its interrelationships with dietary modifications in broiler chicks and ducks. Results of these studies emphasize the many factors that the severity of aflatoxicosis depends on, including animal species, age, presence of mycotoxin adsorbent, and concentration of major dietary nutrients. Exposure to 2 mg/kg cultured AFB1 led to reduced feed intake, BW gain, depressed feed efficiency, increased relative liver weight, negatively affected serum measures and complement activity, …

Subsidies, Aquaculture Technology Adoption, And Welfare Impacts In Ghana And Kenya, Akuffo Amankwah

Open Access Dissertations

This dissertation empirically examines subsidies, aquaculture technology adoption, and welfare implications of fish farming households in Ghana and Kenya. It is divided into three separate chapters, each addressing a specific empirical issue related to aquaculture in the countries.

The second chapter of this dissertation applies the lognormal double hurdle model to a cross-section of fish farms to analyze commercial demand for improved feed, and whether the government feed subsidy program influences private demand for the feed. The results indicate that households’ decisions to participate in improved feed market are affected by the quantity of the subsidized feed received. Once the …

A Unique Perspective On The Demand For Livestock Product Attributes, Elizabeth S. Byrd

Open Access Dissertations

Consumers are increasingly concerned about the social and environmental impacts of the foods they purchase. Both choice experiments and best-worst scaling (BWS) methodology have been used to elicit consumer willingness to pay (WTP) for food attributes and the relative importance of food attributes to consumers. The dissertation consists of four essays. Chapter 2 presents a formal law review article exploring the laws associated with wild game harvest, consumption, and inspections. The remaining three essays (Chapters 3-5) each address an extension or application of choice experiment and/or BWS methodology focused on credence attributes of meat products. Two online surveys were used …

The Role Of African Leafy Vegetables In Food Security, Marcia M. Croft

Open Access Dissertations

African leafy vegetables (ALVs) are a diverse set of crops grown across sub-Saharan Africa. They have been a staple of traditional diets and contain many critical micronutrients but their importance has been largely ignored by researchers and policymakers at the expense of imported crops. Availability, accessibility, and utilization of ALVs are limited by factors across the supply chain. This research investigated seed systems, drought tolerance, hydroponic production, market barriers, consumer preference, and the impact of gender as related to ALVs. We found that ALVs play an important role in food security and that critical differences exist between formal and informal …

Physiological Aspects Of Relative Changes In Nitrogen And Plant Density Stress Tolerances Over A 38-Year Period Of Us Maize Hybrid Introductions, Keru Chen

Open Access Dissertations

Incremental gains in grain yield of maize hybrids over the decades are the consequence of genotype, environment and management interactions. Historically, genetic improvements in newer hybrids have included longer active grain filling periods (achieved by advancing silking and extending functional stay green in maize leaves); stronger source and sink during grain filling; enhanced tolerance to higher density; and canopy architecture changes. Newer hybrids were known to accumulate more dry matter and nitrogen in the post-silking period, but achieving a more comprehensive knowledge of pre-silking and post-silking dynamics required further understanding of dry matter and nitrogen partitioning in individual organs, as …