Diversification Of Ergot Alkaloid Biosynthesis In Natural And Engineered Fungi, Kyle Austin Davis

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ergot alkaloids are a complex family of tryptophan-derived mycotoxins produced by a diverse range of fungi that occupy a wide variety of ecological niches including soil saprotrophs, plant endophytes, pathogens of plants or insects, and opportunistic pathogens of humans and other mammals. Ergot alkaloids are a similarly diverse family of chemicals that elicit a variety of pharmacological activities in animals due to their resemblance to neurotransmitters and high binding affinity for neurological receptors, including those that bind adrenaline, dopamine, and 5-hydroxytryptamine receptors. These structural similarities allow us to create medicines aimed at treating a range of neurological diseases and disorders …

Sense And Sensitivity: Spatial Structure Of Conspecific Signals During Social Interaction, Keshav Ramachandra

Graduate Theses, Dissertations, and Problem Reports (ETD)

Organisms rely on sensory systems to gather information about their environment. Localizing the source of a signal is key in guiding the behavior of the animal successfully. Localization mechanisms must cope with the challenges of representing the spatial information of weak, noisy signals. In this dissertation, I investigate the spatial dynamics of natural stimuli and explore how the electrosensory system of weakly electric fish encodes these realistic spatial signals. To do so In Chapter 2, I develop a model that examines the strength of the signal as it reaches the sensory array and simulates the responses of the receptors. The …

Spatial Variability In Above Ground Carbon Within An Appalachian Forest, Megan A. Ponczek

Graduate Theses, Dissertations, and Problem Reports (ETD)

Forests have long been recognized for their provision of air and water quality ecosystem services to society; but more recently, they have become valuable to the carbon credit markets used as a tool for mitigating climate change. Quantifying above ground carbon storage in forest ecosystems is essential for these carbon credit markets and can also provide insight into factors that control the spatial distribution of carbon in forests. The goal of this study is to assess the degree to which three factors: topography, tree species, and legacies of logging, impact the spatial variability in above ground carbon within a 400x500m …

Spatial Processing Of Conspecific Signals In Weakly Electric Fish: From Sensory Image To Neural Population Coding, Oak Everette Milam

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this dissertation, I examine how an animal’s nervous system encodes spatially realistic conspecific signals in their environment and how the encoding mechanisms support behavioral sensitivity. I begin by modeling changes in the electrosensory signals exchanged by weakly electric fish in a social context. During this behavior, I estimate how the spatial structure of conspecific stimuli influences sensory responses at the electroreceptive periphery. I then quantify how space is represented in the hindbrain, specifically in the primary sensory area called the electrosensory lateral line lobe. I show that behavioral sensitivity is influenced by the heterogeneous properties of the pyramidal cell …

Evaluation Of Low-Grade Red Oak (Quercus Rubra) And Red Maple (Acer Rubrum) As A Raw-Material For Cross-Laminated Timber Panel Production, Matthew Allen Young

Graduate Theses, Dissertations, and Problem Reports (ETD)

Hardwoods in the Appalachian region are traditionally destined for use in furniture, cabinetry, pallets, and railroad ties. The expanding market for Cross Laminated Timber (CLT) is an opportunity for increased utilization of low-quality hardwoods typically used in pallets or equipment mats. Large quantities of low-grade red oak (Quercus rubra) and red maple (Acer rubrum) to be used in CLTs would provide sufficient lumber sources that could foster the growth of CLT manufacturing facilities in the state of West Virginia or Appalachia all together. The objective of this study was to determine the yield distribution of visual structural grade quality lumber …

Response Of Running Buffalo Clover (Trifolium Stoloniferum Muhl Ex. A. Eaton) To Herbaceous Competition And Transplanting In Monongahela National Forest, Ruben E. Sabella

Graduate Theses, Dissertations, and Problem Reports (ETD)

Running buffalo clover (RBC) is a rare perennial plant that grows throughout the American Midwest and the Appalachian Mountains. It requires disturbed forests to establish and proliferate. It has been suggested that, in the past, these conditions were created by buffalo; now logging operations maintain RBC populations. However, forest managers have been looking for ways to create suitable habitat for RBC that do not involve harvesting practices. This could help create new populations in areas that cannot be logged. Once established, competing vegetation might influence RBC abundance and flowering. This study seeks to quantify this influence by measuring the vegetation …

Survival Of Listeria Monocytogenes On Organic Honeycrisp And Fuji Apples During Storage At 5, 12 And 22.5◦C, Connor S. Freed

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study aimed to evaluate and model the survival of Listeria monocytogenes on organic HoneyCrisp (HC) and Fuji (FJ) apples during storage at various temperatures. Fresh organic HC and FJ apples (without wax coating) obtained from a local wholesale market were inoculated with a 2-strain mix of L. monocytogenes followed by storage at 5.0 (22.9% RH), 12.0 (37.0% RH), and 22.5oC (50.4% RH) for 60, 35, 7 days, respectively, and periodically (day-0 to 60) analyzing microbial populations. Surviving L. monocytogenes were spread-plated on Modified-Oxford agar after 10 or 100-fold serial dilution. Data were analyzed using the mixed-model procedure of SAS …

Specialized Metabolism In Retina, Retinal Pigmented Epithelium, And Testis, Siyan Zhu

Graduate Theses, Dissertations, and Problem Reports (ETD)

The retina and its neighboring retinal pigmented epithelium (RPE) are high energy-demanding and metabolically active tissues with specialized and complementary metabolism. They are metabolically interdependent and impact each other’s viability. Interestingly, many of the metabolic features in the retina and RPE are shared with the testis. For example, testis is also energy costly due to continuous sperm differentiation and it has similar metabolic inter-dependence between different testis cells. Both the retina and testis are vulnerable to mitochondrial metabolic impairments.

We conducted three research projects to understand 1) the nutrient utilization and communication in retina and RPE; 2) The profiling of …

The Investigation Of Novel Bovine Oocyte-Specific Long Non-Coding Rnas And Their Roles In Oocyte Maturation And Early Embryonic Development, Jaelyn Zoe Current

Graduate Theses, Dissertations, and Problem Reports (ETD)

Early embryonic loss is a significant factor in livestock species' infertility, resulting in an economic deficit. In cattle, the in vivo fertilization rate is ~90%, with an average calving rate of about 55%, indicating an embryonic-fetal mortality rate of roughly 35%. Further, 70-80% of total embryonic loss in cattle occurs during the first three weeks after insemination, particularly between days 7-16. Growing evidence indicates that the oocyte plays an active role in regulating critical aspects of the reproductive process required for successful fertilization, embryo development, and pregnancy. However, defining oocyte quality remains enigmatic. Recently, many have abandoned the notion that …

Multimodal Neuron Classification Based On Morphology And Electrophysiology, Aqib Ahmad

Graduate Theses, Dissertations, and Problem Reports (ETD)

Categorizing neurons into different types to understand neural circuits and ultimately brain function is a major challenge in neuroscience. While electrical properties are critical in defining a neuron, its morphology is equally important. Advancements in single-cell analysis methods have allowed neuroscientists to simultaneously capture multiple data modalities from a neuron. We propose a method to classify neurons using both morphological structure and electrophysiology. Current approaches are based on a limited analysis of morphological features. We propose to use a new graph neural network to learn representations that more comprehensively account for the complexity of the shape of neuronal structures. In …

Computational Mechanisms Of Face Perception, Jinge Wang

Graduate Theses, Dissertations, and Problem Reports (ETD)

The intertwined history of artificial intelligence and neuroscience has significantly impacted their development, with AI arising from and evolving alongside neuroscience. The remarkable performance of deep learning has inspired neuroscientists to investigate and utilize artificial neural networks as computational models to address biological issues. Studying the brain and its operational mechanisms can greatly enhance our understanding of neural networks, which has crucial implications for developing efficient AI algorithms. Many of the advanced perceptual and cognitive skills of biological systems are now possible to achieve through artificial intelligence systems, which is transforming our knowledge of brain function. Thus, the need for …

Optimizing Sample Collection And Data Interpretation For Effective Wastewater-Based Epidemiology In Combined Sewer Systems, Christopher Allen Anderson

Graduate Theses, Dissertations, and Problem Reports (ETD)

COVID-19 has spurred growth in the science surrounding wastewater-based epidemiology (WBE) pertaining to the detection of severe acute respiratory virus 2 (SARS-CoV-2) in waste streams as an early warning signal for public health. However, the highly variable wastewater environment has made it difficult to standardize an approach for sampling and analysis, especially in locations using combined sewer infrastructure. This study addresses knowledge gaps of WBE via three specific aims: (1) to compare diurnal fluctuations of SARS-CoV-2 and the human fecal indicator, pepper mild mottle virus (PMMoV) in wastewater treatment plant (WWTP) influent samples collected during dry versus wet weather conditions; …

Extension Of The Ergot Alkaloid Gene Cluster, Samantha Joy Fabian

Graduate Theses, Dissertations, and Problem Reports (ETD)

Specialized metabolites produced by fungi impact human health. A large portion of the pharmaceuticals currently on the market are derived from metabolites biosynthesized by microbes. Ergot alkaloids are a class of fungal metabolites that are important in the interactions of environmental fungi with insects and mammals and also are used in the production of pharmaceuticals. In animals, ergot alkaloids can act as partial agonists or antagonists at receptors for 5-hydroxytryptamine (serotonin), dopamine, and noradrenaline as ergot alkaloids have chemical structures similar to those neurotransmitters. Therefore, they affect insects and mammals that consume them and can be used to produce drugs …

Assessing Forest Features And Nocturnal Flying Insect Diversity As Predictors Of Eastern Whip-Poor-Will Occupancy In Foraging Habitat, Clark D. Alexander

Graduate Theses, Dissertations, and Problem Reports (ETD)

Eastern whip-poor-will (Antrostomus vociferus), an insectivorous caprimulgid, have seen an approximate 2.76% annual population decrease since the 1960s, with their breeding and foraging ecology largely unknown due to their nocturnal and cryptic behavior. I conducted research to assess abiotic and biotic variables correlated with detection, and occupancy probability, and prey species diversity on ~104,000 hectares of forest in West Virginia, owned by the private timber company Weyerhaeuser. Previous literature indicates that Eastern whip-poor-will, and their prey, require ephemeral habitat such as recently cleared and early successional forests, like those historically created by forest fires, wind shears, hurricanes, and …

Effects Of Development On Hpa Function Following Pubertal Stress, Brittany D. Elliott

Graduate Theses, Dissertations, and Problem Reports (ETD)

For women, two of the greatest risk factors for affective disorders are adversity experienced during puberty and later becoming pregnant. We have created a translationally relevant mouse model where we address these complex risk factors. Previously, we discovered that pregnant mice (dams) that experienced chronic variable stress (CVS) during puberty display a blunted hypothalamic-pituitary-adrenal (HPA) response when exposed to an acute stressor. Interestingly, this alteration only first becomes apparent during pregnancy, which is a sensitive period for these effects due to normative neuroendocrine changes. Further investigation of the mechanisms underlying this dysfunction revealed altered gene expression in the paraventricular nucleus …

Exogenous Factors That Impact Huntingtin Aggregation, Adam Skeens

Graduate Theses, Dissertations, and Problem Reports (ETD)

While expansion of a polyglutamine (polyQ) domain is the immediate cause of huntingtin (htt) aggregation associated with Huntington’s Disease (HD), other cellular factors modify aggregation. These include interactions with cellular membranes, protein biding partners, molecular crowding, and proteinaceous seeds. Here, two important factors are biophysically characterized: 1) the interaction of htt with endomembranes and 2) proteinaceous seeds obtained from a variety of htt-derived peptides. In the first project, the aggregation of htt at bilayer interfaces and in the presence of divalent cations was investigated. A major cellular factor implicated in altered htt aggregation is the binding of lipids. Furthermore, the …

Investigation Of Early Complex Formation Of Huntingtin Protein With And Without Lipids, Alyssa R. Stonebraker

Graduate Theses, Dissertations, and Problem Reports (ETD)

Huntington’s disease (HD) is a fatal neurodegenerative disease caused by the expansion of the polyglutamine (polyQ) domain of the huntingtin protein (htt). The expansion of the polyQ domain beyond a threshold of approximately 35 repeats triggers complex toxic aggregation mechanisms and results in altered interactions between htt and lipid membranes. Many factors modulate these processes. One such modulator includes sequences flanking the polyQ domain, most notably the first 17 amino acids at the N-terminus of the protein (Nt17), and environmental factors including the presence of membranous structures. Nt17 has the propensity to form an amphipathic a-helix in the presence of …

Drivers Of Change In Mindfulness- And Acceptance-Based Interventions With Athletes: Investigating The Influence Of Dosage, Readiness, And Attitudes, Thomas O. Minkler

Graduate Theses, Dissertations, and Problem Reports (ETD)

Mindfulness- and Acceptance-based interventions (MABIs) are being used with increasing frequency with sport participants. Research suggests that such interventions may promote sport performance and impact performance-relevant factors, although the current quality and quantity of research is low. Specifically, questions about intervention engagement (i.e., dosage), potentially impacted by stage of change and attitudes toward sport psychology, need clarification. The present study utilized a multi-method, quasi-experimental longitudinal design with female- and male- identified NCAA collegiate athletes to investigate the effects of an MABI. Specifically, one NCAA Division II team (n = 16) and three NCAA Division III teams (n = …

Neural Systems Underlying Rdoc Social Constructs: An Activation Likelihood Estimation Meta-Analysis, Rosario Pintos Lobo, Katherine L. Bottenhorn, Michael C. Riedel, Afra I. Toma, Megan M. Hare, Donisha D. Smith, Alexandra C. Moor, Isis K. Cowan, Javier A. Valdes, Jessica E. Bartley, Taylor Salo, Emily R. Boeving, Brianna Pankey, Matthew T. Sutherland, Erica D. Musser, Angela R. Laird

Psychology Faculty Publications

Neuroscientists have sought to identify the underlying neural systems supporting social processing that allow interaction and communication, forming social relationships, and navigating the social world. Through the use of NIMH’s Research Domain Criteria (RDoC) framework, we evaluated consensus among studies that examined brain activity during social tasks to elucidate regions comprising the “social brain”. We examined convergence across tasks corresponding to the four RDoC social constructs, including Affiliation and Attachment, Social Communication, Perception and Understanding of Self, and Perception and Understanding of Others. We performed a series of coordinate-based meta-analyses using the activation likelihood estimate (ALE) method. Meta-analysis was performed …

The Effect Of Blue Mussel (Mytilus Edulis) Extinction On Ecosystem Function In The Gulf Of Maine Rocky Intertidal, Sophia K. Montague

Honors Theses

Stressors associated with climate change including thermal stress and ocean acidification inhibit the growth and reproduction of many species, including the ecologically and economically important blue mussel species in the Gulf of Maine (GOM). Established scaling relationships between mussel size, abundance, and water filtration suggests that the decline of mussels will stunt GOM water filtration. This change in the rate of water filtration could have large effects on the abundance of phytoplankton, abundance of invertebrate larvae, abundance of nutrients and organic material, food web stability, and biodiversity. Overall, this thesis explores the effect of blue mussel (Mytilus edulis) …

The Use Of A Habitat Quality Stress Index To Evaluate Stress As An Analog For Proximate Fitness In The American Crow Within A Matrix Of Landcover Characteristics To Assess Its Potential Contribution To Disease Etiologies, Theodore Lee Grabarz

Antioch University Dissertations & Theses

All organisms occur within spatial and temporal environments to maximize proximate fitness (health) and thus life history outcomes. Previous work has examined the temporal and behavioral aspects of proximate fitness on life history outcomes particularly regarding highly perturbed environments (i.e., climate and land use change, resource extraction, agricultural erosion, etc.). My work focuses on the less examined spatial aspect of these perturbed environments. More specifically, this dissertation examines habitat selection and quality as the basis for understanding stress response (negative and positive feedback mechanisms) to environmental stressors within the larger context of regional or gamma (ɣ) biodiversity. Through the lens …

Morphological, Physiological, And Transcriptional Responses Of Populus Trichocarpa To Water Deficit Stress, Kristin Justine Ratliff

Graduate Theses, Dissertations, and Problem Reports (ETD)

Under the threat of climate change with continued fossil fuel use, investment in developing renewable energies is increasingly important. One category of renewable energy sources, biofuels, is well suited to industries that require a liquid fuel source. However, producing biofuel feedstocks is challenging from a sustainability perspective, as they require extensive land area and resource input to grow on marginal lands. The identification of strategies that feedstock species use to maintain productivity with limited to no resource inputs could aid in the selection of optimal genotypes or targets of breeding or engineering efforts to maximize productivity in feedstock plantations. Some …

Sex Differences In Endothelial Function, Metabolism, And Sleep: Responses To Disrupted Circadian Rhythms, Olga Hecmarie Meléndez-Fernández

Graduate Theses, Dissertations, and Problem Reports (ETD)

Circadian rhythms are endogenous cycles that recur approximately every 24 h, and manifest in virtually every physiological and behavioral process among the vast majority of organisms. These rhythms, sustained by the central circadian clock, the suprachiasmatic nucleus (SCN) of the hypothalamus, allow for optimal timing of biological processes that ensure organisms’ homeostasis, and are entrained to precisely 24 h by daily exposure to light. Disruption of the molecular mechanisms that drive these rhythms have negative consequences on physiology and behavior that may impair survival. The molecular mechanisms that underlie these effects are widely studied and linked to multiple diseases and …

The Effect Of Silver Carp On Large River Community Size Spectra, Bradley R. Novak

Graduate Theses, Dissertations, and Problem Reports (ETD)

The introduction of silver carp (Hypophthalmichthys molitrix) has had dramatic effects on native fish communities. Silver carp are large bodied planktivores and compete with native planktivores which can cause cascading effects throughout the food web. Our study strives to determine the threshold of abundance beyond which silver carp alter fish community structure. We used a community size spectra approach to evaluate fish community structure and compare size spectra across spatial and temporal gradients of silver carp abundances. Community size spectra (CSS) is an ataxic approach quantifying the predictable decrease in fish abundance with increasing body size that reacts …

Cluster Homolog Of Immunoglobulin-Like Receptor Genes In Chicken Immune Responses, Brandi A. Sparling

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation explores the identity and role of immunoglobulin-like (Ig-like) receptors in chickens, with focus on their implications in disease and disease progression. These receptors, wisely expressed across immune cells, interact with the major histocompatibility complex (MHC) class I molecules to modulate immune responses in mammals. Due to the insufficient representation of chicken Ig-like receptors in online databases, this study systematically annotates the chicken Cluster Homolog of Immunoglobulin-like Receptors (CHIR) genes using advanced bioinformatic techniques, aligning with the release of the 7th edition of the chicken genome assembly that comprises builds for a broiler and layer chicken. The analysis identifies …

Investigation Of Regulator Of G Protein Signaling-12 (Rgs12) As A Modulator Of Monoamine Transporters And Behavioral Responses To Cocaine, Allison Noel White

Graduate Theses, Dissertations, and Problem Reports (ETD)

Stimulant use disorder is a psychiatric illness that is characterized by repeated use of stimulant drugs despite harm to the user. There are currently no Federal Drug Administration (FDA)- approved medications for stimulant use disorder, and the number of stimulant use-associated deaths have increased over the past decade. Given the prevalence of and lack of treatments for stimulant use disorder, there is an urgent need to identify new drug targets and treatments for this illness. Our group is investigating Regulator of G protein Signaling-12 (RGS12) as one such potential drug target for stimulant use disorder. Mice lacking RGS12 are insensitive …

Gut-Lung Axis Of The Microbiome Alterations After Ultrafine Particles And Ozone Inhalation, Md Habibul Hasan Mazumder

Graduate Theses, Dissertations, and Problem Reports (ETD)

Air pollution poses a significant threat to public health. It is a mixture of particulate matter, gaseous substances, and other secondary substances. Despite epidemiological research indicating the interactive effects of various components of air pollution, existing studies and regulatory limits often focus on single-exposure scenarios. The emerging understanding of the microbiome’s role in regulating immune response, metabolism, and pathophysiology of various diseases points towards interactions between environmental exposures and microbial dysbiosis. In this dissertation, mice were exposed to relevant deposited doses of carbon black (CB) and ozone (O3), and lung inflammation as well as the lung-gut axis of the microbiome …

Spiking Neural Network That Maps From Generalized Coordinates To Cartesian Coordinates, Chloe K. Guie

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this thesis, I look to understand how insects compute task-level quantities by integrating range-fractionated sensory signals to create a sparse-spatial coding of Cartesian positions. I created biologically plausible 2-D and 3-D models of one species of the stick insect (Carausius morosus) leg and encoded the foot position through a spiking neural network. This model used spiking afferents from three angles of an insect leg which are integrated by one non-spiking interneuron. This model contains many dendritic compartments and one somatic compartment that encode the foot’s position relative to the body. The Functional Subnetwork Approach (FSA) was used …

Cue Reactivity In Electronic Cigarette Users With Sign-Tracking Or Goal-Tracking Behaviors, Polina Krom

Graduate Theses, Dissertations, and Problem Reports (ETD)

Polina Krom

Cue reactivity is an important predictor of addiction course and relapse. However, cue reactivity is only observed after an addiction develops. As such, it is unclear to what degree cue reactivity represents a state stemming from the addiction process versus a trait-like propensity towards developing cue-reward associations. Work in animal models has pointed to important individual differences in trait-like inclination to attribute incentive salience to reward-predictive cues that is associated with addiction-relevant behavioral and neurobiological features. These individual differences manifest as sign-tracking (ST) and goal-tracking (GT) behaviors during Pavlovian conditioning. Little research has attempted to translate ST and …

Abundance-Habitat Relationships And Aquatic-Terrestrial Habitat Selection Patterns For Wood Turtles (Glyptemys Insculpta) In The Upper Midwest, Jena Marie Staggs

Graduate Theses, Dissertations, and Problem Reports (ETD)

Due to range-wide population declines, wood turtles (Glyptemys insculpta) are under review for federal listing under the United States Endangered Species Act. Understanding how habitat associations and environmental conditions influence population dynamics and spatiotemporal activity patterns is fundamental for designing effective management strategies. Previous work on wood turtle abundance-habitat relationships focused on broad-scale habitat relationships in northeastern North America. However, regional differences in climate, habitat conditions, and land use patterns limit their applicability to much of the wood turtle’s Upper Midwest distribution. Much of our understanding of wood turtle activity patterns is based on radiotelemetry studies, which are biased towards …