Digital Commons Network^™

Bee Diversity Of Three Appalachian Shale Barren Sites, Olivia C. Latham

Theses and Dissertations

Insect pollination is vital to ecosystem function. However, climate change, habitat loss, pesticides, and a variety of other anthropogenic sources are contributing to a decline in pollinator diversity. Fragile small ecosystems with a high composition of specialized plant species that rely on specific pollinators such as Appalachian shale barrens, are especially at risk of losing biodiversity. This study combines the use of active sweep net sampling of endemic shale barren forbs and passive trap methods over the course of a bloom season (April-August) in three barren sites to identify bee community populations and visitation relationships between pollinator species and endemic …

Model-Based In-Vitro Pk/Pd Profiling Of Novel Synthetic Allosteric Effectors Of Hemoglobin (Aeh) As Potential Sickle Cell Disease (Scd) Therapeutics, Xiaomeng Xu

Theses and Dissertations

Introduction: Allosteric effectors of hemoglobin (AEH) represent a class of synthetic aromatic aldehydes that transiently form covalent interactions (Schiff-base) with hemoglobin (Hb) to form Hb-AEH adduct, preventing the HbS polymerization and sickling of red blood cells (RBC). The overall objective of this research was to aid in the optimization of novel AEH by understanding their target-site disposition of AEH in relevant biological matrices, e.g., HbA solution, whole blood (WB) and human liver cytosol (HLC), a surrogate of aldehyde dehydrogenase (ALDH)-mediated oxidative metabolism.

Methods: A “universal” HPLC-UV/Vis assay method was developed for the quantitation of HbA-AEH adduct for chemically …

Sphingolipids In Cancer Health Disparities And As Prospective Targets For Cancer Therapy, April E. Boyd

Theses and Dissertations

Lung cancer is the deadliest cancer both in the United States and worldwide. Non-small cell lung cancer (NSCLC) accounts for approximately 85% of all lung cancers. However, lung cancer disparities are not shared equally across racial groups, with large differences between African American and Caucasian populations. Advances in research have revealed roles of lipid mediators in cancer biology and disease progression, but sphingolipid alterations in tissues should be explored further. To address this, using mass spectrometry (MS), extensive sphingolipidomic characterization of NSCLC tumors and adjacent uninvolved tissues from African American and Caucasian patients were performed. This study revealed that NSCLC …

Recovery From Visual Dysfunction Following Mild Traumatic Brain Injury Is Associated With Adaptive Reorganization Of Retinal Inputs To Lateral Geniculate Nucleus In The Mouse Model Utilizing Central Fluid Percussion Injury., Vishal C. Patel

Theses and Dissertations

Traumatic brain injury (TBI) is a leading cause of morbidity and mortality nationwide. Prevalence of mild TBI (mTBI) vastly outnumbers more severe forms however the associated morbidity has only recently gained public attention. Visual dysfunction is a significant component of mTBI associated morbidity with recovery of function linked with improvement in global outcomes. Examination of sensory and motor pathways in other brain injury paradigms support that recovery is largely dependent on adaptive plasticity of remaining connections. Current examinations of visual function recovery following mTBI is limited to identifying evidence for recovery and objective evidence for adaptive plasticity is limited. Therefore, …

Integration Of Multi-Omic Platforms To Understand The Regulation Of Genes In Human Disease, Eva Lancaster

Theses and Dissertations

Epigenetic mechanisms have been hypothesized to modify gene expression (GE) in response to both genetic variation and environmental exposures, ultimately contributing to the development of complex traits. Epigenome-wide association studies (EWAS) aim to test the theory that marks of DNA methylation (DNAm) have downstream consequences that result in the development of complex diseases. Although these methods have been successful in identifying DNAm patterns in complex traits, specific molecular mechanisms involved in the etiology of complex diseases remain unidentified. This knowledge gap does not originate from a lack of DNAm-trait associations, but rather stems from study design issues that affect the …

Multi-Label Classification Models For Heterogeneous Data: An Ensemble-Based Approach., Jose Maria Moyano Murillo

Theses and Dissertations

In recent years, the multi-label classification gained attention of the scientific community given its ability to solve real-world problems where each instance of the dataset may be associated with several class labels simultaneously, such as multimedia categorization or medical problems.

The first objective of this dissertation is to perform a thorough review of the state-of-the-art ensembles of multi-label classifiers (EMLCs). Its aim is twofold: 1) study state-of-the-art ensembles of multi-label classifiers and categorize them proposing a novel taxonomy; and 2) perform an experimental study to give some tips and guidelines to select the method that perform the best according to …

Reducing Material Attractiveness Utilizing Pu-238 And U-232, Cody Lloyd

Theses and Dissertations

Decreasing the material attractiveness of uranium and plutonium materials is crucial to nuclear nonproliferation. The International Atomic Energy Agency (IAEA) implements safeguards across the world on a limited budget. Not only does decreasing material attractiveness reduce the possibility of proliferation, but also may lighten the financial burden on the IAEA if safeguards can be reduced. Two particular isotopes that have negative material attractiveness traits are ²³⁸Pu and ²³²U. Without isotopic separation technology, these isotopes cannot be removed from plutonium and uranium materials respectively. Both ²³⁸Pu and ²³²U produce large quantities of heat by alpha decay. High …

Lpa Receptors Modulate Gene Expression During Oligodendrocyte Differentiation, Samantha A. Spencer

Theses and Dissertations

LPA, produced by the lysoPLD activity of ATX, binds its cognate receptors and regulates the development of multiple brain cells, including oligodendrocytes (OLGs). OLGs progress through a lineage from precursor (OPC) to early OLG to immature OLG, until finally the cells mature and enwrap axons to enable saltatory conduction and provide trophic support. The studies in this dissertation characterized the receptors LPA4 and LPA6 as inhibitors of OPC differentiation. Western blot analysis of MS patient lesion tissue found a negative correlation between ATX levels and levels of LPA4 and LPA6. A previously created homology model for LPA4 was used to …

The Analysis Of Neural Heterogeneity Through Mathematical And Statistical Methods, Kyle Wendling

Theses and Dissertations

Diversity of intrinsic neural attributes and network connections is known to exist in many areas of the brain and is thought to significantly affect neural coding. Recent theoretical and experimental work has argued that in uncoupled networks, coding is most accurate at intermediate levels of heterogeneity. I explore this phenomenon through two distinct approaches: a theoretical mathematical modeling approach and a data-driven statistical modeling approach.

Through the mathematical approach, I examine firing rate heterogeneity in a feedforward network of stochastic neural oscillators utilizing a high-dimensional model. The firing rate heterogeneity stems from two sources: intrinsic (different individual cells) and network …

Stimulated Growth Response To Sand Burial Of A Coastal Shrub, D. Nicole Keller

Theses and Dissertations

Drivers of vegetation zonation on barrier islands are complex and interconnected. Sand burial is a strong driver in dynamic coastal systems, especially in the foredune community. However, it is not well understood how burial impacts the interdunal swales communities and it is especially difficult to separate the effects of burial from salinity. Climate change is altering the frequency of overwash events as well as expanding the range of the native shrub, Morella cerifera, on the Virginia barrier islands. To accurately forecast island response to climate change it is important to understand how the shrub responds to sand burial. Juvenile …

The Effect Of The Senolytic Abt-263 On Androgen Deprivation-Induced Senescent Prostate Tumor Cells, So Min Lee

Theses and Dissertations

Prostate cancer (PCa) is one of the leading causes of cancer-related deaths in men. Although standard treatments such as androgen deprivation therapies (ADT) and antiandrogens have increased survival for many patients, most men placed on these therapies will develop castration-resistant disease (CRPC). Previous studies have shown that these treatments have limited cytotoxicity and instead promote cell growth arrest. Our current work demonstrates that prostate tumor cells grown in the absence of androgens by using charcoal-stripped serum undergo senescence-mediated or senescent-like growth arrest, based on the cellular expression of senescence-associated-beta-galactosidase (SA-β-Gal). Our studies further suggest that this senescence is transient and …

Constraints On Phytoplankton Abundance And Cyanotoxin Production In The Tidal Freshwater James River, Brittany Ann Moretz

Theses and Dissertations

The tidal freshwater James River exceeds chlorophyll-a (CHL-a) water quality standards and the cyanotoxin microcystin is commonly present. Efforts to control harmful algal blooms in the James have brought about significant reductions in nitrogen and phosphorus inputs, but chlorophyll levels have not changed. In order to better understand the factors constraining harmful algal blooms in this system, we performed three factorial mesocosm experiments that tested how light (ambient, enhanced), mixing (weak mixing, well-mixed), and the availability of dissolved inorganic nitrogen (pre/post NH₄⁺ reductions) influence the abundance of phytoplankton (CHLa, particulate organic carbon [POC]) and cyanotoxin production (microcystin, anatoxin) …

A Comparison Of Computer- And Interviewer-Administered Measures To Identify Heavy/Problem Alcohol And Other Drug Use In Primary Care Patients, David J. Pomm

Theses and Dissertations

Substance use is a leading cause of morbidity and mortality that is under-identified in primary care settings. Screening for substance use in primary care requires an efficient and accurate approach. Exploring methods to collect sensitive and accurate data about substance use and related problems is important to inform research practice and clinical care. Using RCT data comparing computerized and therapist delivered brief intervention for substance use problems, the present study had a unique opportunity to compare computerized anonymous and confidential surveys to a confidential, interviewer-administered assessment in a sample of N = 540 males and females at risk for heavy/problem …

Exosomes As Systemic Mediators Of Nanotube Induced Neurotoxicity, Christopher G. Canal

Theses and Dissertations

Extra-pulmonary effects of nanoparticle inhalation have been well documented; however, mechanisms for conveying peripheral bioactivity remain elusive. Recent studies point to indirect molecular mediators shed into the circulation. Protein and lipid alternatives to cytokines or chemokines have been proposed, yet the diversity among responses suggests a broader assemblage of factors. Recently we have proposed proteolytic fragment peptides as an additional source of bioactivity, which interestingly were significantly associated with exosomal proteins after enrichment analysis. Here we tested whether modeled exposure to multi-walled carbon nanotubes (MWCNT) could alter the composition and bioactivity of circulating exosomes. Male C57BL/6 mice were exposed by …

Adverse Childhood Experiences In Children Presenting To Integrated Pediatric Primary Care, Irene A. Jacobs

Theses and Dissertations

The prevalence of adverse childhood experiences (ACEs) has created a significant public health concern in the United States. A vast body of literature examining adult populations has displayed a dose-response association between cumulative ACEs and chronic illnesses (Chapman et al., 2004; Felitti et al., 1998). ACEs research conducted with children and adolescents has indicated higher ACE scores associated with learning and behavioral problems (Burke et al., 2011), health risk behaviors (Garrido et al., 2018), and mental health challenges (Mackner et al., 1997). However, ACEs research and subsequent interventions have largely relied upon retrospective data retrieved from adults (Felitti et al., …

Competing Models Of Exposure To Community Violence Among Urban Youth: Dimensional Versus Person-Centered Approaches, Sarah K. Pittman

Theses and Dissertations

Exposure to community violence is prevalent among urban youth residing in neighborhoods with high rates of crime and violence. Although there is strong evidence suggesting that community violence exposure is associated with negative consequences on youth development, there are inconsistencies in theories and evidence regarding the nature of these associations. Methodological limitations of dimensional approaches to conceptualizing exposure, including the assumption that adolescents are similar in their frequency and patterns of exposure, likely contribute to the inconsistencies in findings of associations. Recently, person-centered methods have been used to elucidate associations between community violence exposure and consequences on adolescent development. However, …

Investigation Of Molecular Mechanisms Of Liver Preservation Injury: A Complication Preceding Organ Transplantation, Ria C. Fyffe-Freil

Theses and Dissertations

Of the over 108,000 American awaiting a life-saving organ transplant today, over 12,000 (11%) of those need a new liver (OPTN, 2020). Last year, only 35% of patients on the waiting list for an organ were transplanted. Improving the quality of marginal organs by preventing or reversing preservation injury could vastly increase the number of transplants performed. Washout of circulating blood during liver procurement with cold University of Wisconsin solution flushes out any endogenous pro-survival signaling molecules. We investigated lysophospholipid (LPL) surface receptors (G-protein coupled receptors for lysophosphatidic acid (LPA) and sphingosine- 1-phosphate (S1P)) and their role in protecting hepatocytes …

Separate And Unequal: Latinx Access, Enrollment And Completion Of Ap Coursework In The State Of Virginia, Virginia Elizabeth Palencia

Theses and Dissertations

In response to the national problem of overrepresentation of Latinx students in general education classes, this study addresses Latinx access to Advanced Placement (AP) coursework, enrollment, and completion patterns in Virginia, a growing destination state for many Latinx families and students. Through a secondary data analysis of both the Civil Rights Data Collection (2015-6) and College Board data (2016), this quantitative study mapped patterns of disproportionality in AP access, enrollment, and completion for Latinx students, who comprise 13% of enrollment in Virginia public high schools. In addition, a case study of two diverse school districts provides evidence of segregation and …

Development And Validation Of Predictive Risk And Multiple Criteria Decision Analysis Models To Evaluate Cardiovascular Outcomes Among Cancer Patients, Purva N. Parab

Theses and Dissertations

Objective: The objectives of our study were to characterize the study population with cancer and cardiovascular diseases (CVD) both as compared to those without and to build a predictive model using machine learning (ML) algorithms that can predict the risk of CVD in cancer patients. In addition, our objective was also to evaluate characteristics associated with cardiotoxic adverse events of breast cancer therapies and develop a multiple criteria decision analysis (MCDA) model to conduct benefit-risk assessment of breast cancer therapy regimens. Methods: We used Medical Expenditure Panel Survey (MEPS) and FDA Adverse Events Reporting System (FAERS) 2005-2015 files along with …

Characterizing Patterns Of Cannabis Use And Related Health Effects Among Young Adults Using Ecological Momentary Assessment, Alyssa Rudy

Theses and Dissertations

Introduction: Rapid changes in cannabis use policy and prevalence, particularly among young adults, and the lack of information regarding cannabis harms warrant investigation regarding the daily use patterns of cannabis users. Little is known regarding how variability in cannabis use frequency and administration method use patterns may be associated with differential acute cannabis-related health effects (i.e., subjective intoxication and respiratory symptoms). The purpose of the study was to characterize daily and weekly cannabis use patterns and associated cannabis-related intoxication and respiratory symptoms and test the interactions of cannabis use frequency and cannabis administration method use on cannabis-related intoxication and respiratory …

Ca2+/Calmodulin-Dependent Protein Kinase Type Ii (Camkii) Regulates Histone Methylation To Promote Zebrafish Hematopoietic Stem Cell Specification, Sanyam Patel

Theses and Dissertations

Ca²⁺/calmodulin dependent protein kinase II (CaMKII) is an important signaling molecule involved in many developmental processes. This project aims to understand the role of CaMKII in specification of hematopoietic stem cells (HSCs) in zebrafish. HSCs undergo hematopoiesis to specify all cells that constitute blood. The process of hematopoiesis along with the specification of hematopoietic stem cells is conserved in vertebrates. CaMKII is expressed in tissues important for HSC specification, including the somites, notochord, and dorsal aorta. The dorsal aorta is the site of HSC specification in zebrafish. Injection of camk2g1 translational blocking antisense oligonucleotides (MO) or Cas9 guide …

The Pseudomonas Aeruginosa Interactome: Insights Into Srna-Mediated Regulatory Networks, Christine M. Van Duyn

Theses and Dissertations

Pseudomonas aeruginosa is a Gram-negative bacterium found in various environmental niches including soil, water, hospital environments, and within a broad range of hosts. It is well known for its metabolic versatility and intrinsic and acquired resistance to a variety of antimicrobial agents. Moreover, this bacterium has a remarkable ability to adapt and survive in suboptimal environments by altering its transcriptional profile in response to nutrient deprivation, changes in temperature and pH, osmotic stress, the presence of reactive oxygen species (ROS), and exposure to antibiotics and host defenses. P. aeruginosa colonizes individuals with compromised immune systems and severe burn injuries and …

Interpersonal Competency Configurations And The School Adjustment Of Early Adolescents With Disabilities: A Person-Centered Approach, Brittany I. Sterrett

Theses and Dissertations

The transition to middle school is a critical time in adolescence. The more complex school environment provides opportunities for growth and challenges for students with disabilities. Although special education strives to provide individualized supports to students with disabilities through data-based decision-making, the tools used to understand and meet the needs of these students are often unresponsive to the dynamic nature of development and student adjustment as they age. Grounded in developmental science, this study sought to create a data collection framework through a person-centered approach to inform the individualization process. Specifically, this study: 1) explored a decision process that allows …

Mechanistic Study Of C-H Activation By Iridium Complexes, Rozalie S G Corea

Theses and Dissertations

C-H activation is considered the “holy grail” of chemistry. Remote, selective C-H activation has many applications such as modifying precursors, adding complexity to molecules, and modifying pre- existing structures in a reduced number of steps. Previous work by Swift and Gronert identified an iridium(III) phenanthroline complex that can activate C-H bonds of cyclohexane. The objective of this dissertation is to study the mechanism and regioselectivity of this complex in common precursors, namely 1-butanol, 1-methoxybutane and butyl acetate.

The studies were carried out in the gas phase on a modified mass spectrometer. Selectively deuterated alcohol, ether and ester were used to …

Comorbidity In Context: Identifying Patterns Of Depressive And Anxiety Symptoms In African American Early Adolescents, Kathryn Behrhorst

Theses and Dissertations

Depression and anxiety during adolescence includes symptoms of irritability, sleeplessness, feelings of guilt or worthlessness, worry, avoidance, and/or restlessness. Anxiety and depressive symptoms are often comorbid and are associated with impairments across academic, social, and emotional areas of functioning. No studies to date have examined patterns of depressive and anxiety symptoms together for African American adolescents using person-centered analyses. The current study examined patterns of symptoms and domains of anxiety and depression during early adolescence using latent profile analyses (LPA). A sample of 196 African American early adolescents in grades six through eight (M_age = 12.6; 50% female) were …

Women’S Perspectives On Human Security: Violence, Environment, And Sustainability, Richard Matthew, Patricia A, Weitsman, Gunhild Hoogensen Gjørv, Nora Davis, Tera Dornfeld

Ohio University Press Open Access Books

Violent conflict, climate change, and poverty present distinct threats to women worldwide. Importantly, women are leading the way creating and sharing sustainable solutions.

Women’s security is a valuable analytical tool as well as a political agenda insofar as it addresses the specific problems affecting women’s ability to live dignified, free, and secure lives. First, this collection focuses on how conflict impacts women’s lives and well-being, including rape and gendered constructions of ethnicity, race, and religion. The book’s second section looks beyond the scope of large-scale violence to examine human security in terms of environmental policy, food, water, health, and economics. …

Influence Of The Digital Divide And Socio-Economic Factors On Prevalence Of Diabetes, Loknath Sai Ambati, Omar F. El-Gayar, Nevine Nawar

Research & Publications

More than 100 million Americans have diabetes or prediabetes (29 and 84 million, respectively). Factors such as overweight, sedentary behavior, and history of diabetes in the family have been commonly associated with the onset of type 2 diabetes. Extant literature now points to the effect of socio-economic factors such as education, income, ethnicity, and physical location on the prevalence of the disease. This research aims to investigate the impact of social determinants on diabetes with a particular emphasis on the digital divide. We used data from the Centers for Disease Control and Prevention (CDC) for diagnosed diabetes prevalence, obesity prevalence, …

Occurrence Of Plant-Parasitic Nematodes On Enset (Ensete Ventricosum) In Ethiopia With Focus On Pratylenchus Goodeyi As A Key Species Of The Crop, Selamawit A. Kidane, Beira H. Meressa, Solveig Haukeland, Trine Hvoslef-Eide, Christer Magnusson, Marjolein Couvreur, Wim Bert, Danny L. Coyne

All Peer-Reviewed Publications

Summary - Enset (Ensete ventricosum) is an important starch staple crop, cultivated primarily in south and southwestern Ethiopia. Enset is the main crop of a sustainable indigenous African system that ensures food security in a country that is food deficient. Related to the banana family, enset is similarly affected by plant-parasitic nematodes. Plant-parasitic nematodes impose a huge constraint on agriculture. The distribution, population density and incidence of plant-parasitic nematodes of enset was determined during August 2018. A total of 308 fields were sampled from major enset-growing zones of Ethiopia. Eleven plant-parasitic nematode taxa were identified, with Pratylenchus (lesion nematode) being …

Morphology, Development And Reproduction Of Atractomorpha Acutipennis (Guérin-Méneville, 1844) (Orthoptera: Pyrgomorphidae), Sévilor Kekeunou, Marcelle Mbadjoun-Nziké, Alain Christel Wandji, Steve Bernard Soh-Baleba, Alfiery Laurel Djomnang-Nkwala, Alain Simeu-Noutchom, Charly Oumarou-Ngoute, Philene Corine Aude Um-Nyobe, Linda Gaelle Guiadem-Simo, Patrick Ntonga Akono

All Peer-Reviewed Publications

For a better knowledge of Atractomorpha acutipennis bio-ecology and to facilitate its identification, we studied the morphology, development and reproduction of this grasshopper on Manihot esculenta under laboratory conditions. Five hundred and fifty-one first nymphal stages obtained in the laboratory were reared in cages. Some body parts allowed a clear identification of different nymphal instars. Post-embryonic development passed through six stages (males) and seven stages (females). Mean nymphal development time was 17.14 ± 0.62, 12.91 ± 0.62, 13.45 ± 0.69, 13.80 ± 0.68, 15.23 ± 0.55 days respectively in males nymphal instars 1 to 5 and 16.18 ± 0.54, 13.13 …

Unlocking Maize Crop Productivity Through Improved Management Practices In Northern Tanzania, Kihara J, Kizito F, Jumbo M, Kinyua M, M. Bekunda

All Peer-Reviewed Publications

Addressing the problem of low crop productivity and food insecurity can be accelerated through community-centered implementation of good agricultural management practices. This study was conducted in Babati, Northern Tanzania. The objective of the study was to determine nitrogen (N) and phosphorus (P) application requirements for maize, and demonstrate economically viable best bet yield-improving management technologies under three ecozones namely; ‘low elevation low rainfall', ‘medium elevation high rainfall' and ‘medium elevation low rainfall' ecozone. Two sets of trials were conducted: N (0, 45, 90, 120 and 150 kg ha-1) and P (0, 15, 30, 40 kg ha-1) response trials in 16 …