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Restriction-Modification And Crispr-Cas Systems: Cooperation Between Innate And Adaptive Immunity In Prokaryotes, Pascal Maguin Jan 2022

Restriction-Modification And Crispr-Cas Systems: Cooperation Between Innate And Adaptive Immunity In Prokaryotes, Pascal Maguin

Student Theses and Dissertations

Bacteria have evolved numerous mechanisms to resist the constant assault of viruses (called bacteriophages, or simply phages) that can infect and kill them. Restriction-modification (RM) systems represent one such strategy. Generally, these systems provide defense by coordinating the activities of two distinct enzymes: a restriction endonuclease and a methyltransferase. Both enzymes recognize the same short DNA sequences. The methyltransferase modifies these target sites in the host chromosome, which prevents the restriction endonuclease from cleaving the host's own DNA. In contrast, foreign phage DNA is usually not methylated at these sequences. Consequently, upon injection into the host, the viral DNA is …

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Novel Optical Tools To Investigate Presenilin Control Of Neurotransmission, Ryan J. Farrell Jan 2022

Novel Optical Tools To Investigate Presenilin Control Of Neurotransmission, Ryan J. Farrell

Student Theses and Dissertations

Neurotransmission is a critical function for neurons that underlies the complex processes of the brain. Deficits in synaptic function often manifest in neurodegenerative diseases, motivating the study of control points of neurotransmission. The Endoplasmic Reticulum (ER) has recently been described as one such control point, as ER Ca2+ levels can regulate the magnitude of synaptic vesicle exocytosis. Here we investigate the controversial hypothesis that Presenilins are ER Ca2+ leak channels to determine if a role in ER Ca2+ leak can explain the previously described regulation of neurotransmission by Presenilins. While Presenilins are best known for their involvement …

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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 …

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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 …

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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 …

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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 …

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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 …

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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 …

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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 …

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Palbociclib Suppresses The Cancer Stem Cell Properties And Cell Proliferation Through Increased Levels Of Mir-506 Or Mir-150 In Panc-1 And Miapaca-2 Cells, Özge Rencüzoğullari, Eli̇f Damla Arisan Jan 2022

Palbociclib Suppresses The Cancer Stem Cell Properties And Cell Proliferation Through Increased Levels Of Mir-506 Or Mir-150 In Panc-1 And Miapaca-2 Cells, Özge Rencüzoğullari, Eli̇f Damla Arisan

Turkish Journal of Biology

The prognostic characteristics of pancreatic cancer (PC) are determined by the contributing factors from the tumor microenvironment. Leptin is a critical oncogenic factor released by adipocytes as an adipokine into the tumor microenvironment, where it promotes tumor development by activating cancer stem cell (CSC) molecular regulators Notch, Hedgehog, and Wnt/ß-catenin signaling. One of the downstream targets of these pathways is CDK4/6 and cyclin D which is controlled by P16 INK4A that is highly mutated in PC. Therefore, the purpose of this study was to determine the effect of a CDK4/6 inhibitor, palbociclib, on Leptin-induced PC cells and to target the …

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Black Vs. White: What Is Bipolar Disorder?, Delmy Mendoza, Kendall Childs, Maedot Aklilu, Tynise Phillips Jan 2022

Black Vs. White: What Is Bipolar Disorder?, Delmy Mendoza, Kendall Childs, Maedot Aklilu, Tynise Phillips

DC Health and Academic Prep Program (DC HAPP)

This intervention will show that underdiagnosing and misdiagnosing mental health disorders can be prevented by creating more high school medical pipeline programs and encouraging POC students interested in healthcare to participate in diversifying the healthcare system. Pipeline programs have shown to be beneficial in increasing the numbers and quality of underrepresented ethnic minority applicants from disadvantaged backgrounds, and achievement motivation. For example, the pipeline program The Teen Medical Academy created in 2008 combated unrepresentative health disparity in adolescents by successfully improving interest in medical and allied health careers, confidence in their ability to accomplish a health profession, learning surgical and …

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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 …

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Menstruation In Marketing: Stigma, #Femvertising, And Transmedia Messaging, Catherine A. Coleman, Katherine C. Sredl Jan 2022

Menstruation In Marketing: Stigma, #Femvertising, And Transmedia Messaging, Catherine A. Coleman, Katherine C. Sredl

School of Business: Faculty Publications and Other Works

No abstract provided.

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Multiunit Housing And Cannabis: Good Laws Make Good Neighbors, Daniel G. Orenstein Jan 2022

Multiunit Housing And Cannabis: Good Laws Make Good Neighbors, Daniel G. Orenstein

Fordham Urban Law Journal

No abstract provided.

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The Rainbow Connection: Revisiting The Mixed-Motive Summary Judgement Standard In Bostock’S Afterglow, Courtney Vice Jan 2022

The Rainbow Connection: Revisiting The Mixed-Motive Summary Judgement Standard In Bostock’S Afterglow, Courtney Vice

Fordham Urban Law Journal

No abstract provided.

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A Critique Of New York Paid Family Leave, Anna Petrocelli Jan 2022

A Critique Of New York Paid Family Leave, Anna Petrocelli

Fordham Urban Law Journal

No abstract provided.

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Expert Testimony On False Confessions: An Old Psychological Problem With New Challenges In New York Courts, Alysia Lo Jan 2022

Expert Testimony On False Confessions: An Old Psychological Problem With New Challenges In New York Courts, Alysia Lo

Fordham Urban Law Journal

No abstract provided.

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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 …

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Mental Health Care And Intimate Partner Violence: Unasked Questions, Delaney E. Anderson, Richard C. Boldt Jan 2022

Mental Health Care And Intimate Partner Violence: Unasked Questions, Delaney E. Anderson, Richard C. Boldt

Journal of Health Care Law and Policy

No abstract provided.

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Tree Root Influence On Building Foundations In Expansive Clay Soils In North Texas, Rocio Vegamartinez Jan 2022

Tree Root Influence On Building Foundations In Expansive Clay Soils In North Texas, Rocio Vegamartinez

2022 Fall Honors Capstone Projects - Archive

Coupled with the expansive soil profile and climatic nature of Texas, trees repeatedly damage pavements and building foundations. The drying of tree roots places residential foundations at risk for soil desiccation and displacement. This research seeks to grasp a better understanding of the relationship between Texas expansive soils, tree root growth, and residential foundations in the North Texas area. This paper presents a case study of a residential house in Arlington, Texas, experiencing foundation cracking and settlement with two large trees on the property. Electrical Resistivity Imaging was done to monitor the relationship between the soil and the tree roots. …

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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 …

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Comparing Prairie Management Methods’ Effects On Three Native Texan Grasses, Stephanie Howell Jan 2022

Comparing Prairie Management Methods’ Effects On Three Native Texan Grasses, Stephanie Howell

2022 Fall Honors Capstone Projects - Archive

The Texas Blackland Prairie habitat is under extreme threat. Currently, only 1% of the original prairie remains. Restoration efforts across the state have aimed to address these concerns. This research set out to test the efficacy of the methods used to restore prairies regarding three grasses. Big Bluestem, Andropogon gerardii, Little Bluestem, Schizachyrium scoparium, and Indiangrass, Sorghastrum nutans, were surveyed to establish their species abundance on two fields in North Texas. Based on their abundance and the history of each field, conclusions were drawn on the efficacy of the maintenance. Seeding was found to be inconsequential for A. gerardii and …

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Increasing Hpv Vaccination In Elliott And Lawrence Counties, Keeghan Francis Jan 2022

Increasing Hpv Vaccination In Elliott And Lawrence Counties, Keeghan Francis

Theses and Dissertations--Public Health (M.P.H. & Dr.P.H.)

Appalachian counties within Kentucky have higher rates of HPV-related cancers, including cervical cancer. HPV vaccines are effective at reducing the risk of cervical cancer, but vaccination coverage in Appalachia remains low. The proposed program relies on recommended strategies to improve vaccine uptake by increasing access and demand for HPV vaccines. This will be done through school vaccine clinics and parent education on HPV, cervical cancer, and HPV vaccines.

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A Program Of Race Betterment: The Emergence And Evolution Of Eugenic Ideas In Michigan, Branden Mceuen Jan 2022

A Program Of Race Betterment: The Emergence And Evolution Of Eugenic Ideas In Michigan, Branden Mceuen

Wayne State University Dissertations

Contemporary concerns with technologies like CRISPR and the proliferation of state laws restricting abortion have led people to wonder if we are witnessing a return of eugenics. I analyze the development and evolution of eugenic ideas and policies throughout the 20th century, using the state of Michigan as a frame of reference. In examining the eugenic theories and policies psychiatrists and physicians endorsed, I demonstrate that eugenics was a key component of preventive public medicine in the first two decades of the 20th century. I show how they educated the public on eugenics based on both environmentalist and hereditarian ideas …

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Academy Presidents And Institutional Members, Academy Editors Jan 2022

Academy Presidents And Institutional Members, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Factors Affecting The Sex Ratio Of White-Tailed Deer (Odocoileus Virginianus) Fetuses In Arkansas, Jorista Garrie, Ralph Meeker Jan 2022

Factors Affecting The Sex Ratio Of White-Tailed Deer (Odocoileus Virginianus) Fetuses In Arkansas, Jorista Garrie, Ralph Meeker

Journal of the Arkansas Academy of Science

Health of the mother is known to affect the sex-ratio of the offspring in sexually dimorphic mammals. Both density-dependent and environmental factors (conditions at present, or seasonal conditions the year before) could impact the health of the mother. There are however two opposing hypotheses for whether a mother in good health should invest more in a strong son (that can father many offspring) or in a daughter (that can stay in the same area and use good resources). Fetuses from 1,208 female white-tailed deer (Odocoileus virginianus) were collected over a 10-year period (2002-2012), across 75 counties in Arkansas. …

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Seasonal Testicular Histology And Acystic Lobular Spermatogenesis In The Western Lesser Siren, Siren Intermedia Nettingi (Caudata: Sirenidae), Stanley E. Trauth Jan 2022

Seasonal Testicular Histology And Acystic Lobular Spermatogenesis In The Western Lesser Siren, Siren Intermedia Nettingi (Caudata: Sirenidae), Stanley E. Trauth

Journal of the Arkansas Academy of Science

I investigated the seasonal testicular histology and acystic lobular spermatogenesis in the Western Lesser Siren, Siren intermedia nettingi, from periodic sampling of this salamander over a span of 21 yr (1994-2015) in northeastern Arkansas. My results include the following general findings: 1) the largest testicular lobules occurred primarily in January-February during spermiogenesis and spermatozoa maturation; 2) lobular regression and spermatogenic cell recrudescence were underway by late March; 3) proliferation of secondary spermatogonia in lobules was prominent in May; 4) transformation of secondary spermatogonia into primary spermatocytes occurred by mid-July, and these cells became larger in diameter through increased nuclear …

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Distribution And Breeding Of The Black-Bellied Whistling-Duck (Dendrocygna Autumnalis) In Arkansas, With A Brief Chronology Of Distribution And Breeding In Southeastern United States, C. Renn Tumlison Jan 2022

Distribution And Breeding Of The Black-Bellied Whistling-Duck (Dendrocygna Autumnalis) In Arkansas, With A Brief Chronology Of Distribution And Breeding In Southeastern United States, C. Renn Tumlison

Journal of the Arkansas Academy of Science

The Black-Bellied Whistling-Duck (Dendrocygna autumnalis) was a rare bird first reported from Arkansas in 1982, when it was seen in Hempstead Co. in southwestern Arkansas. Observations surged in parts of the state about 2005, then again about 2016, and the bird is now fairly common seasonally in many parts of the state. By use of online sources for citizen science, we elucidate the history of occurrence and present analysis of seasonal distribution of this bird in Arkansas. Individuals occur in Arkansas throughout the year, but observations are most common and widely distributed from March-September, after which most individuals …

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Additional Distributional Records For A Rare Caddisfly In The Ozarks, Frenesia Missa (Milne) (Trichoptera: Limnephilidae), David Bowles Jan 2022

Additional Distributional Records For A Rare Caddisfly In The Ozarks, Frenesia Missa (Milne) (Trichoptera: Limnephilidae), David Bowles

Journal of the Arkansas Academy of Science

This paper describes the distribution for this rare species in the Ozarks of Arkansas and Missouri thus expanding its known range in the region. The species is considered vulnerable to anthropogenic stressors.

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Effects Of Clipping Of Flight Feathers On Resource Use In Gallus Gallus Domesticus, Renee Garant, Bret W. Tobalske, Neila Bensassi, Nienke Van Staaveren, Dan Tulpan, Tina Widowski, Donald R. Powers, Alexandra Harlander-Matauschek Jan 2022

Effects Of Clipping Of Flight Feathers On Resource Use In Gallus Gallus Domesticus, Renee Garant, Bret W. Tobalske, Neila Bensassi, Nienke Van Staaveren, Dan Tulpan, Tina Widowski, Donald R. Powers, Alexandra Harlander-Matauschek

Faculty Publications - Department of Biological & Molecular Science

Ground-dwelling species of birds, such as domestic chickens (Gallus gallus domesticus), experience difficulties sustaining flight due to high wing loading. This limited flight ability may be exacerbated by loss of flight feathers that is prevalent among egg-laying chickens. Despite this, chickens housed in aviary style systems need to use flight to access essential resources stacked in vertical tiers. To understand the impact of flight feather loss on chickens’ ability to access elevated resources, we clipped primary and secondary flight feathers for two hen strains (brown-feathered and white-feathered, n = 120), and recorded the time hens spent at elevated resources (feeders, …

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