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Safety Concepts For Every Ride: A Statistical Ensemble Simulation To Mitigate Rotational Falls In Eventing Cross Country, Shannon Wood

Theses and Dissertations--Mechanical and Aerospace Engineering

Rotational falls are the leading cause of death and serious injury in the equestrian sport of eventing. Previous studies to develop safety devices used physical models representing one or at most several physical situations leading to different designs and no common understanding. In this thesis, a statistical ensemble model is developed and applied to generate and evaluate 10,000 different situations that might potentially lead to rotational falls. For accurate statistical representation of the horse and rider inertia distributions, measurements of over 400 training or competing horses and riders were recorded and incorporated. Video was recorded of 218 total competitors approaching …

Bacterial Cell Wall Characterization Via Atomic Force And Confocal Microscopy, Joree Sandin

Theses and Dissertations--Mechanical and Aerospace Engineering

Poor oral hygiene is a severe global health issue, with about 44% of the Earth’s population suffering from untreated tooth decay, accounting for over $100 billion dollars spent on dental services per year in the United States, alone. Manual treatments, such as brushing, flossing, or swishing with antiseptic rinse are the main ways to alleviate harmful bacteria that cause these oral health problems. Streptococcus mutans (S. mutans) is a group of highly antibiotic, Gram-positive bacteria that heavily contribute to oral cavities, plaque build-up, and potential loosening or loss of dental implants if a biofilm develops. Currently, the mechanism …

Breast Implant-Associated Anaplastic Large Cell Lymphoma: Molecular Features, Epidemiological Risk Factors, And Evidence-Based Clinical Recommendations, Ryan Decoster

Theses and Dissertations--Clinical and Translational Science

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is an emerging cancer of the immune system that can form around textured-surface breast implants. In this dissertation, the cellular and molecular mechanisms of BIA-ALCL are reviewed with a focus on the role of oncogenic JAK-STAT3 signaling in BIA-ALCL tumorigenesis and progression. Herein, the epidemiology of BIA-ALCL is systematically studied to better define the risk of BIA-ALCL and to determine the oncologic safety of smooth surface devices relative to BIA-ALCL formation. Next, a systematic review is conducted which critically appraises current clinical guidelines in order to establish an evidence base to better inform …

The Effect Of Haptoglobin Phenotypes On Markers Of Neuroinflammation In Patients With Aneurysmal Subarachnoid Hemorrhage, Kevin Hatton

Theses and Dissertations--Clinical and Translational Science

Aneurysmal subarachnoid hemorrhage (aSAH) is a severe form of hemorrhagic stroke resulting from the spontaneous rupture of an intracranial aneurysm and release of oxygenated blood into the subarachnoid space. In the United States alone, aSAH occurs in approximately 30,000 patients each year and occurs, primarily, in otherwise healthy adults, frequently without warning. Sadly, approximately 40% of patients with aSAH will die in the first 30 days. Of those who survive, only about 75% will be able to live semi-independently again and only about 60% will be able to return to work.

Delayed brain injuries (DBI), which may affect up to …

Legibility Of Communicative Writing And Drawing In Aphasia: Does The Orthographic Medium Matter?, Nicole Waugaman

Theses and Dissertations--Communication Sciences and Disorders

Expressive language difficulties are commonplace in aphasia and are often further complicated by co-occurring motor speech disoders. Therefore, many people with aphasia (PWA) are unable to meet all their communication needs by speaking, and they may compensate with the use of communicative writing and drawing. Communicative writing and drawing can be defined as preserved, but imperfect, orthographic skills that PWA use to compensate for expressive language deficits resulting from aphasic and/or motor speech difficulties. The purpose of this study was to determine if the orthographic medium used by a PWA to write and draw influenced the legibility of their writing …

Transcriptomic And Cellular Response To Mechanical Overload And The Underlying Role Of Macrophages In Extracellular Matrix Remodeling, Bailey D. Peck

Theses and Dissertations--Rehabilitation Sciences

The extracellular matrix (ECM) in skeletal muscle plays an integral role in tissue development, structural support, and force transmission. Upon mechanical loading, including resistance exercise, which alter muscle fiber contractile activity, size, orientation and connectivity, remodeling processes must occur that involve both ECM deposition and degradation. ECM remodeling involves many cell types in muscle, but the focus of our research was directed towards macrophages, which participate in the early immune response to damage and loading. We have consistently demonstrated a significant increase in skeletal muscle macrophage abundance using pan macrophage markers (CD11b/CD68) and anti-inflammatory markers (CD206/CD163) following exercise training in …

The Effects Of Dietary Nitrate And Vitamin C On Endothelial Function And Oxidative Stress Biomarkers, Reem Basaqr

Theses and Dissertations--Pharmacology and Nutritional Sciences

Background: Endothelial dysfunction is associated with a decline in the vasodilator nitric oxide (NO) and presents alongside other cardiovascular risk factors in the early stages of atherosclerosis. Independently, inorganic nitrate and vitamin C supplementation have shown promise in providing some restoration of NO bioavailability, reduced oxidative stress, and improvements in endothelial function. Some preliminary evidence has suggested that vitamin C may augment the reduction of nitrite to further liberate NO and improve cardiovascular health. However, co-supplementation has not been adequately studied. Our objective was to compare the effect of inorganic nitrate in the form of concentrated beetroot juice (CBJ) with …

Functional Impact Of Angiotensinogen Specific Domains On Angiotensin Ii-Mediated Functions, Chia-Hua Wu

Theses and Dissertations--Pharmacology and Nutritional Sciences

Angiotensinogen (AGT) is the only substrate for all angiotensin peptides in the renin angiotensin system (RAS). Cleavage of AGT by renin is a rate-limiting step of angiotensin peptides productions in the RAS and regulates angiotensin peptides-associated pathophysiological functions. Only ten N-terminal residues are cleaved by renin and the functions of remaining part of AGT protein, which is called des(angiotensin I)AGT, remain unclear. Despite of pivotal roles of AGT in the RAS, studies related to how AGT is metabolized and how des(angiotensin I)AGT regulates AGT functions or AngII-mediated functions are limited.

Renin cleavage of AGT shows species specificity. It has been …

Divergence In Neuronal Calcium Dysregulation In Brain Aging And Animal Models Of Ad, Adam Ghoweri

Theses and Dissertations--Pharmacology and Nutritional Sciences

Neuronal calcium dysregulation first garnered attention during the mid-1980’s as a key factor in brain aging, which led to the formulation of the Ca²⁺ hypothesis of brain aging and dementia. Indeed, many Ca²⁺-dependent cellular processes that change with age, including an increase in the afterhyperpolarization, a decrease in long-term potentiation, an increased susceptibility to long-term depression, and a reduction in short-term synaptic plasticity, have been identified. It was later determined that increased intracellular Ca²⁺ with age was due to increased Ca²⁺ channel density, elevated release from intracellular Ca²⁺ stores, and decreased Ca²⁺ buffering …

Role Of Pancreatic Amylin In Alzheimer’S And Brain Microvascular Pathologies, Han Gia Ly

Theses and Dissertations--Pharmacology and Nutritional Sciences

Alzheimer disease (AD) and cerebral vascular disease (CVD) are common causes of impaired cognition and behavior in humans. Epidemiological studies have shown that AD and CVD development and progression associated with metabolic risk factors including type 2 diabetes (T2D). However, the underlying molecular mechanisms remain elusive, which hampers the development of treatment and prevention strategies. Research results from our laboratory and others have shown that amylin, a hormone secreted by the pancreas and involved in glucose homeostasis, induces small-vessel-type pathologies and modulates amyloid composition in both familial (genetically predisposed) and sporadic forms of AD. The results indicate amylin as a …

Apoe As A Metabolic Regulator In Humans, Mice, And Astrocytes, Brandon C. Farmer

Theses and Dissertations--Physiology

Altered metabolic pathways appear to play central roles in the pathophysiology of late-onset Alzheimer’s disease (AD). Carrier status of the E4 allele of the APOE gene is the strongest genetic risk factor for late-onset AD, and increasing evidence suggests that E4 carriers may be at an increased risk for neurodegeneration based on inherent metabolic impairments. A new appreciation is forming for the role of APOE in cerebral metabolism, and how nutritional factors may impact this role. In chapter 1, the literature on nutritional interventions in E4 carriers aimed at mitigating disease risk is reviewed. Studies investigating the mechanism by which …

Striated Muscle Specific Ribosomal Protein L3-Like: Effect Of Knockout On Cardiac Function And Protein Translation, Laura P. Brown

Theses and Dissertations--Physiology

Ribosomes are the molecular machinery of the cell that catalyzes synthesis of peptides from amino acids. The eukaryotic ribosome is made up of four strands of ribosomal RNA (rRNA) and ~80 ribosomal proteins. While many tissues routinely exhibit variations of ribosomal protein stoichiometry, tissue specific ribosomal proteins are rare. The ribosomal protein with the highest tissue specificity of any ribosomal protein is found in striated muscle, ribosomal protein L3-like (RPL3L). Other than its tissue specificity, association with atrial fibrillation, and chromosomal location, there is little known about the function of RPL3L. However, its ubiquitously expressed paralog, RPL3, has been well …

Involvement Of The Renin Angiotensin System In Marfan Syndrome Associated Thoracic Aortic Aneurysms, Jeff Zheying Chen

Theses and Dissertations--Physiology

Thoracic aortic aneurysms (TAAs) are clinically-silent dilations of the aorta which greatly increase the risk of aortic rupture, a condition with 50-90% mortality. Marfan syndrome (MFS) is caused by mutations in fibrillin-1 (FBN1) and is associated with TAAs. Due to an absence of validated and effective pharmacologic therapies to prevent or reverse TAA, most MFS patients require surgical aortic repair. Understanding MFS associated TAA pathogenesis would direct development of new pharmacologic therapies. Previous research has implicated the renin angiotensin system in TAA. In both males and females, angiotensinogen (AGT) is cleaved serially to generate the main effector peptide angiotensin II …

Remodeling In The Actin Core Of The Auditory Hair Cell Stereocilia As A Novel Component Of Temporary Noise-Induced Hearing Loss, Jonathan Michael Grossheim

Theses and Dissertations--Physiology

The rigid, paracrystalline actin core of auditory hair cell stereocilia is extremely stable and after initial formation must persist for the life of the cell to preserve hearing in mammals. In healthy hair cells, turnover of actin molecules occurs only in a small region near the tips of stereocilia, while the actin filaments of the shaft are stable. For decades damage to the actin core of stereocilia from acoustic trauma has only been attributed to cases of permanent noise-induced hearing loss. Here, we show that repairable actin core damage occurs in temporary noise-induced hearing loss from moderate acoustic trauma.

We …

Ceramide-Enriched Extracellular Vesicles: A Role In Enhancing Amyloid-Beta Neurotoxicity And Mitochondrial Damage In Alzheimer’S Disease, Ahmed Elsherbini

Theses and Dissertations--Physiology

Alzheimer’s disease (AD) is an age-dependent, progressive, neurodegenerative disorder that is characterized clinically by the impairment of cognitive functions concomitant with behavioral and personality changes. AD is associated with distinct pathological hallmarks, namely, intracellular neurofibrillary tangles comprised of hyperphosphorylated tau protein, extracellular amyloid beta (Aβ) plaques, and marked brain atrophy. Besides their main role as the core component of amyloid plaques, oligomeric Aβ have been shown to be neurotoxic. The exact mechanism of Aβ neurotoxicity is yet to be elucidated.

Recently, a pathogenic function of small extracellular vesicles- also known as exosomes- has been proposed, suggesting that exosomes can transfer …

Characterizing The Roles Of Pipecolic Acid And Reactive Oxygen Species Metabolic Enzymes In Plant Systemic Immunity, Ruiying Liu

Theses and Dissertations--Plant Pathology

Systemic acquired resistance (SAR), initiated by a plant upon recognition of microbial effectors, involves the generation of mobile signals at the primary infection site, which translocate to and activate defense responses in distal tissues. Among the signals contributing to SAR include salicylic acid (SA), nitric oxide (NO), reactive oxygen species (ROS), glycerol-3-phosphate (G3P), and pipecolic acid (Pip). Our previous studies show there are two branches of SAR signaling pathways in Arabidopsis: one regulated by NO/ROS-G3P and the other by SA. Both NO/ROS-G3P and SA-mediated signaling branches function in parallel during SAR. To better understand the role of Pip in SAR …

Pathogenicity, Toxigenic Potential, And Genomics Of Fusarium Graminearum And F. Meridionale Causing Ear And Stalk Rot Of Maize, Franklin Jackson Machado

Theses and Dissertations--Plant Pathology

Gibberella ear (GER) and stalk rot (GSR) diseases of maize in Brazil are caused mainly by Fusarium meridionale, a species belonging to the Fusarium graminearum species complex (FGSC). Another species within this complex, F. graminearum sensu stricto (hereafter F. graminearum), is second in importance on maize, but is the most common species found causing Fusarium Head Blight disease of wheat in Brazil. The latter species is the predominant cause of GER and GSR in North America, where F. meridionale has not been found thus far. In this dissertation I undertook a comparative analysis of pathogenic, saprophytic, toxigenic and …

Evaluation Of Rhodococcus Equi Susceptibility To Silver Nanoparticle Antimicrobials, Elizabeth Boudaher

Theses and Dissertations--Veterinary Science

Rhodococcus equi is a significant cause of pneumonia in foals and immunocompromised humans. Antimicrobial resistance among R. equi isolates has developed as a consequence of inappropriate stewardship and bacterial evolution, leading to an increased rate of treatment failures that typically result in foal fatality. In the current study, we evaluated the efficacy of antimicrobial silver nanoparticle (AgNP) complexes in controlling R. equi growth. Previous studies characterizing AgNP-induced antibacterial effects in other Gram-positive pathogens led us to hypothesize that silver nanoparticle antimicrobials impact R. equi viability and intracellular replication. We therefore investigated the effect of silver nanoparticle complexes on R. equi …

Donor Age Effects On The Proliferative And Chondrogenic/Osteogenic Differentiation Performance Of Equine Bone Marrow- And Adipose Tissue Derived Mesenchymal Stem Cells In Culture, Jasmin Bagge

Theses and Dissertations--Veterinary Science

Orthopedic injuries are a major cause of lameness and morbidity in horses. Bone marrow (BM)- and adipose tissue (AT) derived mesenchymal stem cells (MSCs) have shown potential to facilitate the repair of orthopedic injuries and are being used increasingly in veterinary clinics. Presently, the use of MSCs as a therapy for equine patients is most commonly applied as autologous transplants, using BM- and AT-MSCs harvested from the patient shortly after the time of injury. Cell-based therapies are therefore delayed to enable primary cell numbers to be expanded in culture. Of concern, however, are human and rodent studies that have shown …

Diet Of A Recently Reintroduced River Otter (Lontra Canadensis) Population In Taos County, New Mexico, Gabriela Alexandra Wolf-Gonzalez

Theses and Dissertations--Forestry and Natural Resources

North American river otters (Lontra canadensis), native to every U.S. state and Canada, experienced extensive population decreases and range reduction until the mid-20th century as a result of overexploitation and habitat loss during European colonization. The last known river otter in New Mexico was killed on the Gila River in 1953, although unverified reports continued thru 2008. After a nearly 60-year absence from New Mexico, 33 adult river otters were reintroduced to the Rio Pueblo de Taos in the northern part of the state between 2008-2010; however, they were not subsequently monitored or studied. I characterized diet of …

Host-Parasite Interaction In Horses: Mucosal Responses To Naturally Acquired Cyathostomin Infections And Anthelmintic Treatment, Ashley Elaine Steuer

Theses and Dissertations--Veterinary Science

Cyathostomins are ubiquitous parasites in equids. In rare cases, cyathostomins lead to a generalized typhlocolitis and death. In healthy horses, local reactions are noted to the mucosal larvae; however, the mechanisms and importance of these reactions have not been elucidated. It has been hypothesized that anthelmintics can alter these reactions. Currently, three drug classes are approved for use in horses against cyathostomins; while all products target the adults, only two products are labeled as larvicidal. Adulticidal therapy is implicated in triggering the typhlocolitis, however, current evidence is contradictory. There is also conjecture that the larvicidal drugs can increase the risk …

Comparative Chondrogenesis Of Interzone And Anlagen Cells In Equine Skeletal Development, Chanhee Mok

Theses and Dissertations--Veterinary Science

At the presumptive sites of future synovial joints during mammalian skeletogenesis, articular cartilage develops from interzone located between the cartilaginous anlagen of bones. Thus, two types of cartilaginous tissues differentiate in close proximity. While anlagen cartilage is transient, progressing through endochondral ossification to form bones, articular cartilage is stable and functions throughout life to facilitate both low friction movement and load distribution. Despite important life-long functional properties, articular cartilage has a very limited intrinsic ability to repair structural defects. On the other hand, structural lesions in bones generally heal well by forming a cartilaginous callus and recapitulating endochondral ossification to …

Long-Term Effects Of Crop-Tree Release On The Growth And Quality Of Upland White Oak Stands, Philip Jay Vogel

Theses and Dissertations--Forestry and Natural Resources

The alteration of historical disturbance regimes, forest parcelization, and varying goals among landowners all present challenges to oak management in the eastern U.S. Foresters and landowners need tools to promote oak sustainability that are applicable on small forestland holdings and within complex management plans. From this perspective, this research evaluates a crop-tree release study installed in southeastern Kentucky in 1983. The experiment includes four, 2-acre replications of three treatment levels: 20 crop-trees per acre, 34 crop-trees per acre, and a control treatment in which crop-trees were selected but not released. Half-acre measurement plots were installed at the outset of the …

Effects Of Shelterwood And Patch Cut Harvests On A Post White-Nose Syndrome Bat Community In The Cumberland Plateau In Eastern Kentucky, Phillip Lee Arant

Theses and Dissertations--Forestry and Natural Resources

The impact of shelterwood and patch cuts harvests on bat communities was tested at three sites in Eastern Kentucky. Shelterwood harvests had 50% of the basal area and understory removed to create a uniform spacing of residual trees. Patch cuts had 1-hectare circular openings created to remove 50% of the basal area creating an aggregated spacing of residual trees. Acoustic detectors were deployed to assess activity levels pre-harvest. Sites were then sampled from 1 – 2 years post-harvest to determine differences. Pre-harvest data revealed little acoustic activity for the Myotis spp. at two sites. The remaining site had high activity …

Aggregation Behavior In The Bed Bug, Cimex Lectularius L., Paul D. Baker

Theses and Dissertations--Entomology

The bed bug, Cimex lectularius L., is a common household pest that feeds on the blood of its human hosts. Unlike many other hematophagic arthropods, bed bugs have not demonstrated the ability to vector disease; yet its presence in a household often leads to fear and anxiety amongst its human host victims. Bed bugs spend the majority of their time aggregating in enclosed and hidden locations, making it difficult to detect and eradicate them. One of the significant mediators of aggregation behavior is an aggregation pheromone. The pheromone has been identified to be six chemical compounds, five volatile compounds that …

Physiological Ecology Of Overwintering And Cold-Adapted Arthropods, Leslie Jean Potts

Theses and Dissertations--Entomology

Given their abundance and diversity, arthropods are an excellent system to investigate biological responses to winter. Winter conditions are being majorly impacted by climate change, and therefore understanding the overwintering biology of arthropods is critical for predicting ecological responses to climate change. In Chapters 2 and 3, I investigate the winter biology of a winter-active wolf spider. I show that winter-active spiders can take advantage of periodic prey resources and grown in the winter, which may allow them to get a jumpstart on spring reproduction. I also investigate spiders’ ability to track changes in their environment by quantifying low temperature …

Emerald Ash Borer Development Across A Latitudinal Gradient: Implications For Biocontrol, Sarah Pellecchia

Theses and Dissertations--Entomology

Emerald ash borer, EAB, (Agrilus planipennis Fairmaire) is an invasive beetle that kills ash trees. It was accidentally introduced from China, and has rapidly expanded across North America, now occupying much of the eastern US. Four classical biocontrol parasitoids have been released to help mitigate its spread and impact: Tetrastichus planipennisi Yang, Spathius agrili Yang, S. galinae Belokobylskij and Strazanac, and Oobius agrili Zhang and Huang. These parasitoids have been deployed throughout EAB’s invaded range, but there has been limited recovery of the parasitoids from their release sites in southern states. I evaluated whether this lack of establishment might …

Management Of Stink Bugs (Hemiptera: Pentatomidae) On Soybean In Kentucky, Yaziri Gonzalez

Theses and Dissertations--Entomology

Phytophagous stink bugs (Hemiptera: Pentatomidae) are pests of significant importance to soybean, Glycine max (L.), because they can cause severe losses in seed quality, ultimately affecting yield. Damage to soybean is caused through a process called extra-oral digestion. This occurs when the adults and nymphs of stink bugs pierce plant tissues with their mandibular and maxillary stylets, insert digestive enzymes, break down tissue, and extract the digested plant fluid. Three endemic stink bug species of North America are present in Kentucky: green stink bug (Chinavia hilaris), brown stink bugs (Euschistus species complex), and red-shouldered stink bug (Thyanta custator) …

An Educational Pilot Intervention To Increase Environmental Health Literacy Among Rural Kentucky Youth Attending Summer Camp, Ashley Rose Mattingly

Theses and Dissertations--Nutrition and Food Systems

Risk factors, including exposure to environmental pollutants, poor dietary and overall health outcomes, and low environmental health literacy (EHL), place the rural Appalachian youth population at increased risk for chronic diseases. Implementation of nutrition and pollution curriculum into two week-long summer day camps for youth ages 5-12 years that focus around healthy lifestyles and environmental stewardship has the potential to increase health protective action in this community. This research utilized qualitative interviews of 30 Kids on the Creek Camp attendees to determine the efficacy of the implementation of an active learning lesson to increase EHL by explaining the link between …

Cardiac Effects Of Obesity During Pregnancy In C57bl/6j Mice, Kayla Lynn Dudick

Theses and Dissertations--Nutrition and Food Systems

Objective: Pregnancy requires profound cardiac and metabolic adaptation. Left ventricular (LV) mass is increased in response to pregnancy, but is not associated with cardiac damage. In contrast, obesity-mediated cardiac hypertrophy is pathological. Data from animal studies indicate dietary fatty acid composition may have a protective effect during states of extreme cardiac physiological adaptation. In contrast, aberrant cardiac metabolism is a hallmark of disease. Over a third of reproductive-age women in the United States are obese, but there is a paucity of data describing the effect of obesity on maternal cardiac adaptation to pregnancy. The objective of this study was to …