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2022

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Endogenous Neurosteroid Hormone Production And Early Oligodendricyte Development, Paige Winokur Jan 2022

Endogenous Neurosteroid Hormone Production And Early Oligodendricyte Development, Paige Winokur

Student Theses and Dissertations

The field of neuroendocrinology grew immensely with the realization that steroid hormone production is not confined to the adrenal and reproductive glands but also occurs in the central nervous system (CNS). Steroids synthesized de novo in the brain and spinal cord are referred to as neurosteroid or neuroactive hormones and encompass estrogens, androgens, glucocorticoids, and mineralocorticoids. Though all substrates and enzymes required for neurosteroid biosynthesis exhibit CNS expression, a thorough comprehension of their functionality is lacking. In addition to mediating stress responses, neurosteroids influence CNS-specific processes known to regulate neural development and pathology. Multiple sclerosis (MS), a debilitating neurodegenerative disorder …


The Genetic And Neural Basis Of Sexual Dimorphism In Mosquito Behavior, Nipun Basrur Jan 2022

The Genetic And Neural Basis Of Sexual Dimorphism In Mosquito Behavior, Nipun Basrur

Student Theses and Dissertations

Only female mosquitoes of the species Aedes aegypti have evolved to hunt humans in order to feed on their blood. In striking contrast, male mosquitoes have no drive to seek hosts or drink their blood. Through the act of blood-feeding, only female mosquitoes can transmit pathogens that cause deadly diseases like dengue, chikungunya, and Zika. The genetic and neural circuit basis of this striking sex difference in behavior, one that is of critical importance to global public health, remain poorly characterized. Across the insects, sex-specific alternative splicing is known to control sex-specific morphological and behavioral traits. We took advantage of …


Integration Sites In The Persistence Of Latent Hiv-1, Amy S. Huang Jan 2022

Integration Sites In The Persistence Of Latent Hiv-1, Amy S. Huang

Student Theses and Dissertations

Human immunodeficiency virus (HIV-1), the pathogen that causes acquired immune deficiency syndrome (AIDS), remains one of the world's most pressing health issues. Since the beginning of the HIV/AIDS epidemic, over 32M people have succumbed to AIDS-related illnesses. Despite remarkable advances in HIV-1 biology, neither a vaccine or cure have been achieved. While antiretroviral therapy (ART) has significantly improved disease outcomes for people with HIV-1 and reduced transmission, treatment is often accompanied by long-term side effects or stigma, or impeded by limited access to health care. Furthermore, because viral load quickly rebounds upon treatment interruption, ART is required to be a …


Reproductive Resilience Of Aedes Aegypti Mosquitoes, Krithika Venkataraman Jan 2022

Reproductive Resilience Of Aedes Aegypti Mosquitoes, Krithika Venkataraman

Student Theses and Dissertations

Female Aedes aegypti mosquitoes impose a severe global public health burden as vectors of viruses that cause dengue, chikungunya, yellow fever, and Zika, and parasites that cause lymphatic filariasis. Under optimal environmental conditions, Aedes aegypti females have access to human hosts that provide blood proteins required for egg development, conspecific males that provide sperm required for fertilization, and freshwater in natural or manmade containers that serves as an egg-laying substrate suitable for offspring survival during larval and pupal stages. As global temperatures rise, Aedes aegypti females are faced with climate challenges like intense droughts and intermittent bouts of precipitation, which …


Non-Canonical Odor Coding Ensures Robust Mosquito Attraction To Humans, Margaret Herre Jan 2022

Non-Canonical Odor Coding Ensures Robust Mosquito Attraction To Humans, Margaret Herre

Student Theses and Dissertations

Aedes aegypti mosquitoes spread deadly diseases, including dengue, Zika, yellow fever, and chikungunya. Only female mosquitoes bite, and they do so because they require a blood-meal for reproduction. Aedes aegypti prefer to bite human hosts, which contributes to their effectiveness as a deadly disease vector. Mosquitoes rely heavily on chemosensory cues, including carbon dioxide (CO2) emitted from breath and human body odor, which is a mixture of more than 200 different individual odorants. Although the exact odor profile of people varies considerably, Aedes aegypti are incredibly reliable in finding humans to bite, despite widespread efforts to by humans to mask …


Modulation Of Prefrontal Cortex Activity And Sociability By Local Interneurons Expressing Corticotropi-Releasing Hormone, Michael Riad Jan 2022

Modulation Of Prefrontal Cortex Activity And Sociability By Local Interneurons Expressing Corticotropi-Releasing Hormone, Michael Riad

Student Theses and Dissertations

The cerebral cortex is composed primarily of two neuronal cell types: excitatory pyramidal cells and inhibitory interneurons. Their neurochemical diversity and complex organization into interconnected laminar and columnar circuits imbues the cortex with countless computational and functional possibilities. At the behavioral level, changes in the molecular profile and electrophysiological activity of cortical neurons produce noticeable changes in perception, learning and memory, motor skills, and executive cognitive functions. In the initial chapter of this thesis, I briefly cover the history and progress of cell type studies in cerebral cortex and provide frameworks for understanding and interrogating interneuron diversity. We next apply …


Transcriptomic And Proteomic Studies Of Intercellular Communication Between Melanocytes And Keratinocytes In Human Skin, Gabriella Stephanne Spitz-Becker Jan 2022

Transcriptomic And Proteomic Studies Of Intercellular Communication Between Melanocytes And Keratinocytes In Human Skin, Gabriella Stephanne Spitz-Becker

Student Theses and Dissertations

The epidermis is a stratified epithelium composed of multiple cell types. Keratinocytes are the most prevalent cells in the epidermis and provide the barrier function of the skin. Interspersed amongst the keratinocytes in the basal layer of the epidermis are melanocytes, the pigment producing cells of the epidermis. Melanocytes produce melanin pigment which resides in melanosomes, organelles that are transferred to keratinocytes. In my thesis work, I focused on identifying downstream results of intercellular communication between melanocytes and keratinocytes for each of these cell types. I characterized the transcriptomes of human melanocytes and keratinocytes that were freshly derived from human …


Ultra-Fast And Multi-Dimensional Face Processing In A New Face Area, Zetian Yang Jan 2022

Ultra-Fast And Multi-Dimensional Face Processing In A New Face Area, Zetian Yang

Student Theses and Dissertations

Faces contain a plethora of information crucial for social interactions. Facial information could be transmitted either through facial shape or motion. The last two decades have established that a network of face-selective areas in the temporal lobe of macaque monkeys supports the visual processing of faces. Most of these studies focused on the processing of static facial shape. They found that each area within the face network contains a large fraction of face-selective cells. And each area encodes facial identity and head orientation differently. A recent brain imaging study discovered a new face area outside of this classic network, the …


Uncovering Regulators Of Whole-Body Metabolism By Chemoproteomic Profiling Of The Adipocyte Secretome, Chan Hee J. Choi Jan 2022

Uncovering Regulators Of Whole-Body Metabolism By Chemoproteomic Profiling Of The Adipocyte Secretome, Chan Hee J. Choi

Student Theses and Dissertations

A major threat to human health, obesity is associated with increased risk of cardiometabolic complications such as cardiovascular disease, type 2 diabetes, hypertension, and many types of cancers. Whereas white adipocytes efficiently store energy in the form of triglycerides, thermogenic brown and beige adipocytes can dissipate energy into heat. Adipose tissue is now considered an important endocrine organ, and increasing evidence suggests that divergent metabolic effects of different types of adipocytes are in part mediated by their secretory function. In addition, dysregulation of adipose tissue's secretory function in the setting of chronic positive energy balance plays a central role in …


The Effect Of Early Dietary Intervention On Alzheimer's Disease-Related Pathology And Cognitive Function In Mice, Anna Amelianchik Jan 2022

The Effect Of Early Dietary Intervention On Alzheimer's Disease-Related Pathology And Cognitive Function In Mice, Anna Amelianchik

Student Theses and Dissertations

Alzheimer's disease (AD) is a fatal cognitive disorder with proteinaceous brain deposits, neuroinflammation, cerebrovascular dysfunction, and extensive neuronal loss. AD is a multifactorial disease, and lifestyle factors, including diet, are likely associated with the development of AD pathology. Since obesity and diabetes are recognized as risk factors for AD, it might be predicted that a high fat diet (HFD) would worsen AD pathology. However, modeling HFD-induced obesity in animal models of AD has yielded inconclusive results. Some studies report a deleterious effect of HFD on Aβ accumulation, neuroinflammation, and cognitive function, while others report that HFD worsens memory without affecting …


Sensory And Neuromodulatory Entrainment Of Foraging States In C. Elegans, Elias Scheer Jan 2022

Sensory And Neuromodulatory Entrainment Of Foraging States In C. Elegans, Elias Scheer

Student Theses and Dissertations

Foraging animals dynamically adjust their behavioral patterns over time to optimize feeding in their environment. In the nematode Caenorhabditis. elegans, foraging animals alternate between states of locomotory arousal. I observed that animals in low activity states remain nearby food patches, whereas highly aroused animals often exit patches to explore the external environment. Using different methods of behavioral state classification reveals different aspects of foraging behavior: previously described high arousal roaming and low arousal dwelling states reflect long-term changes in locomotory patterns, whereas an Autoregressive Hidden Markov model that classifies behavior on shorter time scales effectively segments food leaving behaviors. Adaptive …


Dna Methylation And Dna Methyltransferases In The Clonal Raider Ant, Ooceraea Biroi, Ivasyk Iryna Jan 2022

Dna Methylation And Dna Methyltransferases In The Clonal Raider Ant, Ooceraea Biroi, Ivasyk Iryna

Student Theses and Dissertations

DNA methylation and DNA methyltransferase enzymes (DNMTs) are ubiquitous and predate the origin of eukaryotes. In animals, DNA methylation primarily is carried out by DNMT1, which targets hemi – methylated DNA and maintains methylation patterns through cycles of cell replication, and DNMT3, the de novo methyltransferase. These genes are essential to mammalian development, and mutations lead to embryonic (DNMT1 and DNMT3b) or post – natal (DNMT3a) lethality. Studies of DNA methylation and DNMTs in invertebrates have been limited to non – traditional model organisms because Caenorhabditis elegans and Drosophila melanogaster lack the DNMT enzymes, and their DNA has no detectable …


Intestinal Cd4+T Cell Responses To Food, Ainsley Lockhart Jan 2022

Intestinal Cd4+T Cell Responses To Food, Ainsley Lockhart

Student Theses and Dissertations

During routine digestion and absorption of food, massive quantities of diet-derived polypeptides pass through the intestine. The intestinal immune system must maintain tolerance to these dietary antigens while still protecting against pathogens and noxious agents. Oral tolerance, a robust mechanism whereby oral administration of antigen results in both local and systemic tolerance to that antigen, is a key component of this critical homeostasis. Oral tolerance requires CD4+ T cells including specifically regulatory T cells (Tregs), however the role of intestinal CD4+ T cells and the T cell repertoire in a physiological response to food protein remains largely unexplored. …


Tumor Suppression By A Trna Synthetase, Maria Passarelli Jan 2022

Tumor Suppression By A Trna Synthetase, Maria Passarelli

Student Theses and Dissertations

Despite substantial progress in treatment, breast cancer remains a leading cause of cancer mortality among women. During malignant transformation, healthy mammary cells must bypass tumor suppressive checkpoints and activate pro-growth pathways. Enhanced protein translation is one such hallmark of tumor transformation and cancer progression; many oncogenes promote translation by driving synthesis and activity of translational machinery. In the first part of this thesis, we report the surprising finding that leucyl-tRNA synthetase (LARS), a tRNA synthetase responsible for ligating leucine to corresponding leucyl-tRNAs, becomes strongly repressed during mammary cell transformation and in breast cancer. Monoallelic genetic inactivation of LARS in mouse …


Ras Drives Malignancy Through Stem Cell Crosstalk With The Microenvironment, Shaopeng Yuan Jan 2022

Ras Drives Malignancy Through Stem Cell Crosstalk With The Microenvironment, Shaopeng Yuan

Student Theses and Dissertations

Squamous cell carcinomas (SCCs) are triggered by marked elevation of RAS/MAPK signaling and progression from benign papilloma to invasive malignancy. A subset of tumor-initiating basal progenitors, the cancer stem cells, obtain increased resistance to chemo and immunotherapy along this path. However, the distribution and changes in cancer stem cells during progression from a benign state to an invasive SCC remain elusive. Here we show that following HRASG12V activation, cancer stem cells rewire their gene expression program and trigger self-propelling, aberrant signaling crosstalk with their tissue microenvironment that drives their malignant progression. Surprisingly, the non-genetic, dynamic cascade of crosstalk involves pathways …


Structural Studies Of The Nucleolar Stages Of Ribosome Biogenesis In Yeast, Linamarie Miller Jan 2022

Structural Studies Of The Nucleolar Stages Of Ribosome Biogenesis In Yeast, Linamarie Miller

Student Theses and Dissertations

The ribosome is the RNA-protein machine responsible for the essential task of translating mRNA into proteins. Ribosomes are heterodimers made up of a small subunit (SSU, 40S) and a large subunit (LSU, 60S). At the interface of these subunits, the mRNA is decoded by the small subunit and peptide bond formation is catalyzed by the rRNA of the large subunit. The cell therefore requires the timely and accurate assembly of functional ribosomal subunits, a complex process termed ribosome biogenesis. In addition to the ribosomal RNAs and ribosomal proteins that make up the mature subunits, eukaryotic cells require over 200 trans-acting …


Sign-Inverting Vectors Underlie A Coordinate Transformation In The Drosophila Central Brain, Itzel Gonzalez Ishida Jan 2022

Sign-Inverting Vectors Underlie A Coordinate Transformation In The Drosophila Central Brain, Itzel Gonzalez Ishida

Student Theses and Dissertations

Our coherent sense of orientation is built from combining sensory experiences across different modalities. How animal brains compute and remember the directions of motion of the body, limbs, objects or landmarks in a shared reference frame is only now becoming clear.This dissertation focuses on a system of neurons that signals wind direction in the Drosophila central brain. We found that the activity of these neurons, called PFNa, can be thought of as a set of vectors whose summed activity yields the direction of wind in an allocentric reference frame — that is, relative to external landmarks like the sun, as …


Songbird Brain Organization And Its Molecular Convergence With Humans For Vocal Imitation Learning, Gregory Gedman Jan 2022

Songbird Brain Organization And Its Molecular Convergence With Humans For Vocal Imitation Learning, Gregory Gedman

Student Theses and Dissertations

The rich diversity of neural cell populations and their specialized connections give rise to a suite of complex behaviors across vertebrates. The presence of common neural cell types may be a product of either shared ancestry through homology or parallel evolution through convergence. However, the extent as to which these two processes are utilized by diverse nervous systems is poorly understood. Understanding the evolutionary relationships of these neural populations, both within and across vertebrate species, is critical for the study of complex trait evolution. Here, I investigate these two evolutionary processes within the adult avian brain and their impact on …


Human Antibody Response To Flaviviruses And Sars-Coronavirus-2, Marianna Elizabeth Agudelo Jan 2022

Human Antibody Response To Flaviviruses And Sars-Coronavirus-2, Marianna Elizabeth Agudelo

Student Theses and Dissertations

The last decade has seen a number of viral epidemics and global pandemic. Increased global connectivity makes the likelihood of future mass outbreaks ever greater. Understanding the adaptive immune response to these pathogens will expand basic understanding of viral immunity mechanisms and can help inform vaccine and therapeutic development. This thesis describes the characterization of the human antibody response to several important viral pathogens, all of which are either emerging pathogens posing significant public health burdens or are already responsible for epidemic outbreaks. These include tick-borne encephalitis virus (TBEV), Powassan virus (POWV), Zika virus (ZIKV) and severe acute respiratory syndrome …


Nonlinear Representation Of Auditory Stimuli Across The Auditory Cortex, Frank Tejera Leon Jan 2022

Nonlinear Representation Of Auditory Stimuli Across The Auditory Cortex, Frank Tejera Leon

Student Theses and Dissertations

The neural evoke activity to pure tones in primary auditory cortex has been systematically studied for many years, as has the spatial organization of these responses. Unlike pure tones, natural sounds possess complex spectro-temporal structures across frequencies. How simple tuning properties scale across ensembles of neurons to represent more complex sensory environments is still a question of active investigation and debate. To better understand the coding principles used to represent complex auditory sounds, we performed 2-photon calcium imaging of neural activity of the entire auditory cortex in awake mice, while playing sounds composed of single or multiple frequencies. While we …


Building An Allocentric Traveling-Direction Signal Via Vector Computation, Cheng Lyu Jan 2022

Building An Allocentric Traveling-Direction Signal Via Vector Computation, Cheng Lyu

Student Theses and Dissertations

Many behavioral tasks require the manipulation of mathematical vectors, but, outside of computational models, it is not known how brains perform vector operations. Here we show how the Drosophila central complex, a region implicated in goal-directed navigation, performs vector arithmetic. First, we describe a neural signal in the fan-shaped body that explicitly tracks a fly's allocentric traveling angle, that is, the traveling angle in reference to external cues. Past work has identified neurons in Drosophila and mammals that track an animal's heading angle referenced to external cues (e.g., head-direction cells), but this new signal illuminates how the sense of space …


Peptidergic Signaling Controls The Dynamics Of Sickness Behavior In Caenorhabditis Elegans, Javier Marquina-Solis Jan 2022

Peptidergic Signaling Controls The Dynamics Of Sickness Behavior In Caenorhabditis Elegans, Javier Marquina-Solis

Student Theses and Dissertations

Disease is accompanied by modifications to host behavior that promote recovery and survival. The neural and molecular mechanisms that rule the switch to a sickness behavioral state are an active area of research. One established model for sickness behavior is the interaction between Caenorhabditis elegans and the pathogenic bacteria Pseudomonas aeruginosa PA14. After a few hours of exposure to and infection by PA14, C. elegans develops a sickness-like behavior termed pathogen avoidance. Here I identify neuronal signals generated during the infection and associate them with antagonistic circuits that shape the host behavior. Using an unbiased cell-directed neuropeptide screen, I show …


A Developmental Pathway For Epithelial-To-Motoneuron Transformation In C. Elegans, Alina Rashid Jan 2022

A Developmental Pathway For Epithelial-To-Motoneuron Transformation In C. Elegans, Alina Rashid

Student Theses and Dissertations

During animal development, neurons and neuron-like cells are generated from progenitor cells that often line tubes. For example, in the developing spinal cord, basal processes of radial glial stem cells line the fluid-filled spinal canal. Notch/Delta signaling is implicated in the differentiation of these cells into motoneurons through control of their proliferative state. Down-regulation of the Notch-dependent Hes1 and Hes5 transcriptional inhibitors in differentiating cells induces expression of the proneural bHLH transcription factors Olig2 and Ngn2, leading to adherens junction loss, delamination from the epithelium, cell migration, and neuronal maturation. A similar sequence of events characterizes formation of pancreatic insulin-secreting …


Strengthening An Understanding And Practice Of Spiritual Transformation For Sunday School Teachers Of Ellis Chapel Baptist Church, Patterson Springs, Nc, Linda Williams Lockhart Jan 2022

Strengthening An Understanding And Practice Of Spiritual Transformation For Sunday School Teachers Of Ellis Chapel Baptist Church, Patterson Springs, Nc, Linda Williams Lockhart

Doctor of Ministry Projects

The spiritual formation process can be clearly viewed through the lives of those who lived during the biblical era. People desire to change; however, the problem is that they do not know how because training in the spiritual formation process is not present within many churches today. This project was designed to train selected Sunday School teachers of Ellis Chapel Baptist Church through a four-week spiritual transformation process, hoping to strengthen their understanding of becoming image-bearers and practitioners of the Gospel that Jesus taught and exemplified. Through utilizing spiritual disciplines in journaling, training sessions, and assessments, selected teachers became aware …


Optimal Speed Control Of Electric Vehicles In Traffic With Wireless Charging, Amina Jemi Jan 2022

Optimal Speed Control Of Electric Vehicles In Traffic With Wireless Charging, Amina Jemi

All Graduate Theses, Dissertations, and Other Capstone Projects

With the increase in electric vehicle use in recent years and expected increase in the future, a wireless network provides a possible option to allow vehicles with a route while maintaining an approximate net-zero energy balance under certain scenarios. In this type of network, a collection of wireless charging pads is installed under the road, and energy transfer occurs, while a vehicle with wireless charging capability is driven over the charging pads. This thesis describes a methodology and modeling to solve an optimization problem involving a speed-controlled vehicle in traffic. The methodology incorporates a receding horizon dynamic model with constraints. …


Reconstructing Regional Paleoenvironments And Geomorphic History Of High Plains Playa-Lunette Systems, Alyssa E. Sims Jan 2022

Reconstructing Regional Paleoenvironments And Geomorphic History Of High Plains Playa-Lunette Systems, Alyssa E. Sims

All Graduate Theses, Dissertations, and Other Capstone Projects

Playas are ephemeral upland-embedded wetlands found in semiarid and arid regions worldwide. Lunettes are isolated dunes that form along the downwind margin of playas. The paleoclimatic and geomorphic history of High Plains playa-lunette systems (PLSs) are poorly understood. To address this, we characterize the stratigraphy of four PLSs in southwest Kansas, USA. Methods include: 1) collect soil-sediment cores from playa centers and windward slopes of lunettes; 2) describe cores using USDA techniques; 3) estimate age of stratigraphic units using radiocarbon (14C); and 4) reconstruct paleoenvironmental conditions using stable carbon isotopes (13C) and particle size analysis. Playa stratigraphy is relatively simple …


Disorder: The Impact Of Structure And Function On Transcranial Magnetic Stimulation Treatment Response, Daniel Martin Mccalley Jan 2022

Disorder: The Impact Of Structure And Function On Transcranial Magnetic Stimulation Treatment Response, Daniel Martin Mccalley

MUSC Theses and Dissertations

Alcohol Use Disorder (AUD) is the third leading cause of preventable death in the United States. While there are several treatment options available, none of these interventions specifically target the neural circuits known to contribute to alcohol use, abstinence, and relapse. In the following chapters, this dissertation will introduce transcranial magnetic stimulation (TMS) as a potential neural-circuit based therapeutic tool for AUD. Following a brief introduction to the neural circuitry involved in AUD (Chapter 1), Chapter 2 reviews the results of a multimodal randomized, double-blind, sham-controlled trial evaluating 10 sessions of TMS delivered to the frontal pole as a therapeutic …


Epidemiology And Management Of Frogeye Leaf Spot Of Soybean: Damage Thresholds, Efficacy And Profitability Of Foliar Fungicides, Jhonatan Paulo Barro Jan 2022

Epidemiology And Management Of Frogeye Leaf Spot Of Soybean: Damage Thresholds, Efficacy And Profitability Of Foliar Fungicides, Jhonatan Paulo Barro

Theses and Dissertations--Plant Pathology

Frogeye leaf spot (FLS), caused by Cercospora sojina, is an economically important disease of soybean in many parts of the world where soybean is grown, including the United States. A meta-analytic approach was used to summarize a data set of 66 uniform field research trials conducted to evaluate fungicide efficacy against FLS on soybean. The dataset spanned 10 years (2012 to 2021) of experiments conducted across eight states in the U.S., including Alabama, Arkansas, Illinois, Iowa, Kentucky, Louisiana, Mississippi and Tennessee. First, the relationship between FLS severity and soybean yield was investigated. A significant negative slope obtained through random …


The Regulation Of Lab-Grown Meat Under Existing Jurisdictional Authority, Kate Sollee Jan 2022

The Regulation Of Lab-Grown Meat Under Existing Jurisdictional Authority, Kate Sollee

Journal of Health Care Law and Policy

No abstract provided.


The Negative Effects Of Cannabis On Memory Processes, Kiera Wingo Jan 2022

The Negative Effects Of Cannabis On Memory Processes, Kiera Wingo

2022 Fall Honors Capstone Projects - Archive

The purpose of this review is to determine if there is a negative effect of cannabis on memory processes. Specifically, the negative effects of cannabis on short-term, working, and episodic memory were examined within acute or chronic users. Several formal databases and Google Scholar were used to find relevant literature, where key words provided search parameters and narrowed results. A final total of 29 relevant studies were used in the results. The resulting literature employed numerous study methods including N-back, Sternberg, verbal recall measures, and neuroimaging techniques. The results confirmed a negative relationship between cannabis and memory when participants were …