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Diurnal Variation In Co2 Efflux By Pine Seedlings And Root-Associated Mycorrhizal Fungi, Richard Easterling
Diurnal Variation In Co2 Efflux By Pine Seedlings And Root-Associated Mycorrhizal Fungi, Richard Easterling
Honors Theses
This project was part of a larger experiment conducted by Amber Horning and Jason Hoeksema in the Department of Biology at the University of Mississippi, which was set up to investigate variation (over time, and with different light levels) in resource exchange between pine seedlings and two different species of ectomycorrhizal (EM) fungi. The experiment was conducted in a growth chamber, with mycorrhizal pine seedlings growing in plexiglass "mycocosms." I worked with two EM fungal species (Rhizopogon roseolus and Pisolithus arhizus, hereafter "Rhizopogon" and "Pisolithus"), which were collected locally near Oxford, Mississippi under loblolly pine. I selected a subset of …
Auditory Radiation And Cognitive Decline: Probabilistic Tractography Study, Adryanna Tucker
Auditory Radiation And Cognitive Decline: Probabilistic Tractography Study, Adryanna Tucker
Honors Theses
The relationship between hearing loss and Alzheimer’s disease has been studied for many years. Previous studies have shown a negative correlation between the two. In our study, we investigated the relationship between the strength of the auditory radiation connections and the severity of cognitive decline. To do so, we assessed probabilistic tractography using DTI data of the primary auditory pathway. Further, we assessed the level of cognition using the Alzheimer's Disease Assessment Scale-Cog to determine the relationship between the auditory connections assessed in each patient and that patient’s level of cognitive decline. We found that FA and AD were positively …
An Investigation Of Possible Reservoirs Of Lymphoproliferative Disease Virus Of Turkeys In Mississippi, Walker Hyche
An Investigation Of Possible Reservoirs Of Lymphoproliferative Disease Virus Of Turkeys In Mississippi, Walker Hyche
Honors Theses
Emerging infectious diseases are a problem among wildlife and domestic populations. It is critical for these diseases to be studied. Lymphoproliferative disease virus is a retrovirus affecting turkeys and chickens. Prior research originally identified the virus in the United Kingdom and Israel. The first case of LPDV in the United States was found in 2009 in Arkansas. This study tests different reservoirs for the virus. DNA was extracted from samples of different origins and preservation types. Through PCR and gel electrophoresis analysis, different sample types from turkey populations were tested for LPDV. This study provides a method for submitting blood …
Effects Of Mycoplasma Gallisepticum On Experimentally Infected Eastern Bluebirds (Sialia Sialis), Meredith A. Fry
Effects Of Mycoplasma Gallisepticum On Experimentally Infected Eastern Bluebirds (Sialia Sialis), Meredith A. Fry
Honors Theses
The bacterium Mycoplasma gallisepticum is an avian respiratory pathogen that causes inflammation and swelling of conjunctiva in domestic poultry and wild finches. In the past, severity of conjunctivitis symptoms has been used to quantify infection severity and host resistance. However, many songbirds function as hosts to M. gallisepticum but do not develop this symptom at all. The absence of conjunctivitis, as well as other clinical signs, hinders our understanding of M. gallisepticum infection in the songbird community because some species are responding very differently than others. One such species is the Eastern Bluebird (Sialia sialis), a common songbird of the …
Histone Deacetylase Inhibitors And Breast Cancer Metastasis: A Review And Exploration Of Hdac(I)S And Other Chemotherapeutic Agents, William E. Sistrunk
Histone Deacetylase Inhibitors And Breast Cancer Metastasis: A Review And Exploration Of Hdac(I)S And Other Chemotherapeutic Agents, William E. Sistrunk
Honors Theses
The traditional perspective of Histone Deacetylase enzymes is focused on their inherent epigenetic modification characteristics. While it is true that the histone modification these enzymes exhibit play a role in cancer and related diseases, Histone Deacetylase has a variety of non-histone targets. The non-histone targets include microtubules and are of specific interest because of the microtubules’ role in cell line differentiation, replication, apoptosis, and cancer metastasis. Using a variety of Histone Deacetylase Inhibitors (HDACi) and other chemotherapeutic compounds, our research group explored the HDACi effect on breast cancer cell lines. Our goal was to indicate the presence of HDACi cell-line …
Screening For Mental Health Concerns Across Pregnancy : Factors Associated With Depression And Anxiety Symptons In A Large Obgyn Clinic, Addie Keller
Honors Theses
Depression and anxiety are prevalent among pregnant women, however, mental health continues to be a portion of care neglected in the obstetric setting. Depression is of-ten thought of as a disorder that leads to a persistent feeling of sadness. Anxiety is charac-terized by excessive fear and worry. Because of the many changes occurring throughout pregnancy, both physically and emotionally, it is not uncommon for pregnant women to struggle with depression, anxiety, or both. Previous studies have found that there are many factors associated with depression and anxiety throughout pregnancy. This study focuses on the relationship between age, gravida, and social …
Effects Of The Pathogen Mycoplasma Gallisepticum Transmission On Growth And Condition Of Eastern Bluebirds Nestlings (Sialia Sialis), Gurshan Kaur
Honors Theses
A critical aspect to understanding disease dynamics is to understand how transmission occurs between hosts. There are two basic modes of transmission: vertical and horizontal. Vertical transmission is the passage of a pathogen from mother to offspring before or during birth, whereas horizontal transmission occurs between an infected host to a susceptible host. Mycoplasma gallisepticum (MG) is a common bacterial pathogen of poultry that causes respiratory disease. Infection of MG often results in weight loss, slowed growth rate, and increased mortality. Both vertical and horizontal transmission of MG have been found to occur in poultry. In the mid-90s, MG underwent …
O-Glcnacylation Of Hif-1Α Protein In Human Breast Cancer Cells, Joshua D. Dolsen
O-Glcnacylation Of Hif-1Α Protein In Human Breast Cancer Cells, Joshua D. Dolsen
Honors Theses
Cancer is an insidious disease that, if not caught in time, can cause devastating effects on the human body, especially if it metastasizes. It is important to note that each cancer behaves and develops differently based on its location in the body and the cellular characteristics constitute the instance of the disease. However, the development of cancer can universally be characterized by the acquisition of different hallmark abilities that promote disease progression. Proteins known as hypoxia-inducible factors (HIFs) can influence progression through these hallmarks, but primarily provides cancer cells with the ability to alter its metabolism to survive and further …
Neuroprotection With Novel Anti-Oxidant And Cannabinoid-Based Small Molecules, Jacqueline R. Mcgrath
Neuroprotection With Novel Anti-Oxidant And Cannabinoid-Based Small Molecules, Jacqueline R. Mcgrath
Honors Theses
Neurodegenerative diseases are caused by various underlying mechanisms within the nervous system. Excitotoxicity is a hallmark of many neurodegenerative diseases, and is produced by over excitation of glutamate receptors on neurons, ultimately leading to cell death. Protein aggregates and oxidative stress have also induced neuronal cell death that lead to many neurodegenerative diseases as well. Many compounds isolated from plants have shown protective ability against these underlying toxicity mechanisms. In this study, we tested several cannabinoid and anthyocanin-based small molecules protective abilities against excitotoxicity. We found several compounds that protected against glutamate-induced excitotoxicity in a concentration-dependent manner. We also tested …
The Upright Go Wearable Posture Device: An Evaluation Of Postural Health, Improvement Of Posture, And Salivary Cortisol Fluctuations In College Students, Alexandra Lauren Elliott
The Upright Go Wearable Posture Device: An Evaluation Of Postural Health, Improvement Of Posture, And Salivary Cortisol Fluctuations In College Students, Alexandra Lauren Elliott
Honors Theses
Health professionals consider improper posture as a risk factor for musculoskeletal disorders, chronic pain, and additional health issues. The chief aim of my study was to investigate links between poor posture and health, particularly in college students. To collect data regarding postural health, I distributed an exploratory survey to Human Anatomy and Physiology II (BISC 207) students at the University of Mississippi in Spring 2018. Students reported significant concern with quality of personal posture and significant experience with negative side effects of poor posture. Results demonstrated a need for postural education, leading to phase 2 of my experiment, the evaluation …
Bacteria In Salt Pans Along The Mississippi Gulf Coast, Lauren A. Lawson
Bacteria In Salt Pans Along The Mississippi Gulf Coast, Lauren A. Lawson
Honors Theses
Salt pans form in shallow depressions in the ground where salt water evaporates leaving a hypersaline environment remaining. These pans become flooded during extremely high tides and as time progresses, this additional salt water is evaporated leaving behind more salt deposits. Marine salt pans can provide habitat for halophilic microorganisms and provide an interesting environment for study as conditions can change with both sediment and water depth. Towards the surface of sediment in salt pans, oxygen is still available, however, deeper sediments have limited oxygen availability and are likely anaerobic. Deeper sediments can also have higher salt concentrations so may …
Interactions Of Fentanyl With Gp120 In The Central Nervous System, Meagan Buchanan
Interactions Of Fentanyl With Gp120 In The Central Nervous System, Meagan Buchanan
Honors Theses
The Human Immunodeficiency Virus (HIV) has affected more than 75 million individuals worldwide. HIV not only affects the peripheral system through the targeting of T cells, but also causes adverse effects in the central nervous system. Individuals suffering from HIV often experience neuropathic pain and are prescribed opioids to combat the chronic pain. Along with the increase of opioids prescribed to HIV patients, the number of deaths related to the synthetic opioid, fentanyl, has increased drastically. Drug abuse and HIV are interlinked epidemics; individuals who are HIV positive and referred to as “NeuroAIDS.” The HIV envelope protein, gp120, has been …
Deducing The Reproductive, Behavioral, And Learning Effects Of Developmental Cannabinoid Exposure In Zebrafish, Marisa L. Kutchma
Deducing The Reproductive, Behavioral, And Learning Effects Of Developmental Cannabinoid Exposure In Zebrafish, Marisa L. Kutchma
Honors Theses
With the spreading legalization of marijuana, it is important to investigate the effects of two of its active ingredients—Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD). THC and CBD differ in that THC exerts psychoactive effects, while CBD does not. Thus, CBD is renowned for its analgesic effects in treating a variety of ailments, for example, childhood drug-resistant epilepsy. In addition, there is an increase in reports of prenatal CBD usage. As it is increasingly used, research has fallen far behind the proliferation of CBD and more needs to be done, particularly in the developmental realm. This study utilizes a developmental origins of …
Time Course Effects Of Repetitive Social Defeat Stress On A Prefrontal Cortex-Dependent Cognitive Flexibility Task, Shaffer Hannah
Time Course Effects Of Repetitive Social Defeat Stress On A Prefrontal Cortex-Dependent Cognitive Flexibility Task, Shaffer Hannah
Honors Theses
Stress is known to change the structure and function of the brain in animals and humans as well as their behavior. It has a high correlation with the development of psychiatric disorders as well. We looked to investigate how repetitive intermittent social defeat stress using the resident-intruder paradigm in rats affected a cognitive flexibility task. The task used was a set-shifting protocol known to be associated with the function of the prefrontal cortex. Measurements on the task were taken intermittently between social stress sessions to determine short-term effects and 10 days after the last social stress session to measure long …
Resting State Fmri Study Of The Olfactory Region In Autism, Madlyn Lawrence
Resting State Fmri Study Of The Olfactory Region In Autism, Madlyn Lawrence
Honors Theses
This thesis was conducted to further the investigation of the Olfactory system of a typically developing individual compared to an individual with Autism. The Olfactory system is unique in that it is the only sensory system that is not relayed through the thalamus in the brain. Autism Spectrum Disorder (ASD), also known as Autism, is a developmental disorder which impairs a person's social, behavioral, developmental, cognitive and psychological aspects. Autism Spectrum Disorder can present with symptoms such as difficulty communicating, difficulty with social interactions obsessive thoughts and compulsions and repetitive behaviors. Subjects with Autism Spectrum Disorder present with an inability …
Microbial Communities Associated With Dragonfly Nymphs Raised In Varying Concentrations Of Amoxicillin, Michelle Basha
Microbial Communities Associated With Dragonfly Nymphs Raised In Varying Concentrations Of Amoxicillin, Michelle Basha
Honors Theses
The bacteria on and within an organism make up that organism’s microbiome. Given interest in the use of antibiotics in agriculture and the effect of microbes on human health, more studies are needed on the microbial community composition of different organisms and how it responds to antibiotic use. This study investigated changes in the amount of antibiotic resistant bacteria present in dragonfly nymphs exposed to differing concentrations of amoxicillin. Next generation sequencing of the 16S rRNA gene was used to identify cultures of these antibiotic resistant bacteria. Increasing the concentration of antibiotics the dragonfly nymphs were exposed to resulted in …
Diversification In The Neotropics – Evolution And Population Genetics Of The Armored Catfish Hypancistrus Sp. From The Xingu River, Marcella Goncalves Santos
Diversification In The Neotropics – Evolution And Population Genetics Of The Armored Catfish Hypancistrus Sp. From The Xingu River, Marcella Goncalves Santos
Electronic Theses and Dissertations
The Xingu River, one of the largest tributaries of the Amazon River, is currently in peril due to the recent construction of hydroelectric dams, but little is known about the numerous fish species it supports. This dissertation focuses on three pleco catfish species belonging to the genus Hypancistrus from the Xingu River with partially overlapping distributions: H. zebra, H. sp. (L174), and H. sp. (L66/333). Chapter 1 is a bibliographic review of Amazonian freshwater fish diversity, with the goal of discussing the hypotheses of speciation mechanisms that can be tested in this system, including the relative importance of ecological adaptation …
The Evolution Of Coral Snake Mimicry, Renan Janke Bosque
The Evolution Of Coral Snake Mimicry, Renan Janke Bosque
Electronic Theses and Dissertations
Scientists have regarded mimicry as one of the most amazing examples of the power of natural selection. Early observations by naturalists of the mimetic association between venomous New World coral snakes of the genus Micrurus and harmless mimics has stimulated an intense debate about the causes and consequences of mimicry that persists today. Despite its medical, evolutionary and historical importance our understanding of evolution within the genus Micrurus is negligible. My dissertation explores the evolution of mimicry within South American coral snakes and their mimics using a multi-scale framework involving macroevolutionary (Chapter I), geographic/morphological concordance (Chapters II and III), behavioral …
Effects Of Impoundments On The Community Assemblage And Gene Flow Of Stream Crayfishes, Zanethia Choice Barnett
Effects Of Impoundments On The Community Assemblage And Gene Flow Of Stream Crayfishes, Zanethia Choice Barnett
Electronic Theses and Dissertations
Dams and their impoundments block movement of stream organism and change stream physiochemical properties, which subsequently changes biological assemblages and creates barriers to gene flow. While changes in species assemblages and gene flow have been assessed for numerous impoundments and stream organisms, no study has assessed the effects of large impoundments on crayfish assemblages and population genetic diversity and connectivity. I examined the physiochemical, biological, and genetic effects of impoundments on crayfishes. Between May 2015 and August 2017, I sampled multiple sites up- and downstream of three impounded streams, and along the lengths of two unimpounded streams, in the Bear …
Examining The Role Of Reproductive Interference In The Decline Of Native Green Treefrogs Following Cuban Treefrog Invasions, Joseph Kennedy
Examining The Role Of Reproductive Interference In The Decline Of Native Green Treefrogs Following Cuban Treefrog Invasions, Joseph Kennedy
Electronic Theses and Dissertations
Reproductive interference occurs when the mating behaviors of one species negatively impact the fitness of another species. It is of increasing interest in invasive species biology because the introduction of alien species often leads to novel sexual interactions with native taxa, which can contribute to their decline. I examined whether reproductive interference plays a role in the decline of native green treefrogs (Hyla cinerea) following invasions of Cuban treefrogs (Osteopilus septentrionalis) in the southeastern United States. The impetus for this study revolves around similarities in spectro-temporal features of Cuban treefrog courtship calls and green treefrog aggressive calls. The significance of …
Extended Adolescence: The Ecology And Endocrinology Of Facultative Paedomorphosis, Jason R. Bohenek
Extended Adolescence: The Ecology And Endocrinology Of Facultative Paedomorphosis, Jason R. Bohenek
Electronic Theses and Dissertations
Phenotypic plasticity is an adaptation to unpredictable environments whereby an organism of a single genotype may express more than one phenotype under differing environmental conditions. Phenotypic plasticity can manifest as polyphenisms, which is an extreme form of phenotypic plasticity that produces two or more discrete, alternative phenotypes. The expression of alternative phenotypes is controlled by biotic and abiotic environmental factors, which variably affect the strength and direction of phenotypic outcomes. Using a model polyphenic salamander, I sought to understand the ecological and hormonal processes that regulate alternative phenotype expression. The mole salamander (Ambystoma talpoideum) and eastern newt ( …
The Role Of The Age/Rage Signaling Pathway In Cardiac Fibroblast Migration, Mallory B. Harmon
The Role Of The Age/Rage Signaling Pathway In Cardiac Fibroblast Migration, Mallory B. Harmon
Honors Theses
Diabetes is one of the leading causes of death in the United States with around 30 million who suffer from diabetes and 84 million who are considered pre-diabetic. Diabetic individuals are at an increased risk for developing cardiovascular disease due to a stiffening of the left ventricle, which is thought to occur through fibroblast “activation” mediated by increased AGE/RAGE signaling. Advanced glycated end products (AGEs) accumulate within the body overtime and are accelerated under hyperglycemic conditions, and AGEs exert their effects by binding to their receptor (RAGE). Fibroblast “activation” is marked by elevated levels of α-smooth muscle actin expression and …
The Developmental And Behavioral Effects Of Early Life Stage Cannabinoid Exposure, Mariegene E. Almand
The Developmental And Behavioral Effects Of Early Life Stage Cannabinoid Exposure, Mariegene E. Almand
Honors Theses
As of 2019, marijuana legalization and decriminalization is sweeping the globe. Patients are increasingly using cannabis-derived compounds including Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) for treatment of diseases as diverse as epilepsy, Parkinson’s disease, and cancer. Furthermore, mothers are claiming that CBD oil decreases uncomfortable pregnancy side effects. While the adverse effects of chronic cannabinoid use and of cannabinoids on pregnancy have been previously investigated, the exact function of the endocannabinoid system, and its primary receptors, cannabinoid receptors 1 and 2, involved in producing these outcomes is still unclear. In this study, two strains of zebrafish embryos, namely fli and cnr2-/- …
The Effects Of Retrieval Strategy On A Collaborative Reconstruction Task, Amanda M. Bullock
The Effects Of Retrieval Strategy On A Collaborative Reconstruction Task, Amanda M. Bullock
Honors Theses
The purpose of the present experiment was to explore the effects of using various retrieval strategies on a collaborative reconstruction task. More specifically, we sought to determine the extent to which the Retrieval Strategy Disruption Hypothesis (RSD) could explain the effects of collaborative inhibition on such tasks. Collaborative inhibition is observed when collaborative group performance is lower than the pooled performance of an identical number of individuals working alone (nominal groups). The RSD hypothesis suggests that one group member’s output disrupts another group member’s idiosyncratic retrieval strategy leading to poorer performance relative to individuals working alone. In the present study, …
Fungal-Algal Speed Dating: Exploring Symbiotic Potential Of Fungal-Algal Cocultures, Natalie S. Williams
Fungal-Algal Speed Dating: Exploring Symbiotic Potential Of Fungal-Algal Cocultures, Natalie S. Williams
Honors Theses
Symbiotic relationships are widely studied phenomena in the biological world. Of particular interest are the ubiquitous relationships that exist between fungi and photoautotrophs. While much is known about the commonly occurring interactions that persist between fungi and a wide range of terrestrial plants, we are interested in exploring the symbiotic capacity between fungi and earlier diverging lineages of the plant kingdom, notably green algae. We developed an experiment to allow for a medium-throughput analysis of fungal-algal interactions using three model green algae: Chlamydomonas reinhardtii, Chlorella vulgaris, and Penium margaritaceum. With numerous replicated assays, these algae were individually paired with a …
Application And Refinement Of Molecular Ecology Techniques For Amphibian Conservation, Stephanie Marie Burgess
Application And Refinement Of Molecular Ecology Techniques For Amphibian Conservation, Stephanie Marie Burgess
Electronic Theses and Dissertations
Wildlife conservation has become increasingly difficult due to habitat loss habitat fragmentation and land use change. Thus conservationists have embraced advances in molecular ecology such as landscape genetics and microbial bioinformatics that employ genetic techniques to further understand the relationship between individuals and their environment. In landscape genetics model inferences can be used to identify features that facilitate or resist gene flow providing a framework for anticipating the impacts of land use changes on a species’ ability to disperse. However the factors that affect the transferability of landscape genetics inferences are poorly understood and little is known about the effect …
The Role Of Dunc13 In Ethanol Tolerance, Yusuke Wachi
The Role Of Dunc13 In Ethanol Tolerance, Yusuke Wachi
Electronic Theses and Dissertations
Although the effects of ethanol on presynaptic activity have been studied, the molecular mechanisms and the changes in gene expression which are responsible for inducing ethanol tolerance are unclear. Munc13-1 is an active-zone protein that is essential for presynaptic vesicle fusion. This protein interacts with vesicle fusion machinery at presynaptic active zones in the mammalian brain. The C1 domain of Munc13-1 binds diacylglycerol (DAG), which helps membrane localization of this protein and promotes vesicle fusion, facilitating synaptic vesicle release. Previously, it was shown that ethanol binds to the C1 domain of Munc13-1 in vitro at concentrations below 100 mM (Das …
Variations In The Dragonfly Microbiome Through Life Stages And Its Ability To Harbor Antibiotic Resistant Bacteria, Sarah Russell
Variations In The Dragonfly Microbiome Through Life Stages And Its Ability To Harbor Antibiotic Resistant Bacteria, Sarah Russell
Electronic Theses and Dissertations
Juvenile dragonflies (nymphs) may possess the ability to pass their microbiome to the adult life stage through metamorphosis. If this is so, the environment in which the nymph develops may have an effect on the adult microbiome. In this study, the gut microbiomes of 13 species of dragonfly were compared across life stages and when collected from environments at different levels of urbanization. The gut of each dragonfly was removed, DNA extracted, and a portion of the bacterial 16S rRNA gene amplified and sequenced. Gut suspensions were also plated on antibiotic amended plates to determine the potential for dragonflies to …
Analysis Of Brevundimonas Subvibrioides Developmental Signaling Systems Reveals Unexpected Differences Between Phenotypes And C-Di-Gmp Levels, Lauryn Anne Sperling
Analysis Of Brevundimonas Subvibrioides Developmental Signaling Systems Reveals Unexpected Differences Between Phenotypes And C-Di-Gmp Levels, Lauryn Anne Sperling
Electronic Theses and Dissertations
The DivJ-DivK-PleC signaling system of Caulobacter crescentus is a signaling network that regulates polar development and the cell cycle. This system is conserved in closely related bacteria, including the sister genus Brevundimonas. Previous studies had shown unexpected phenotypic differences between the C. crescentus divK mutant and the analogous mutant of Brevundimonas subvibrioides, but further characterization was not performed. Here, phenotypic assays analyzing motility, adhesion, and pilus production (the latter characterized by a newly discovered bacteriophage) revealed that divJ and pleC mutants have mostly similar phenotypes as their C. crescentus homologs, but divK mutants maintain largely opposite phenotypes than …
An Experimental Test Of Controls On Resource Exchange In An Ectomycorrhizal Mutualism, Amber Lynn Horning
An Experimental Test Of Controls On Resource Exchange In An Ectomycorrhizal Mutualism, Amber Lynn Horning
Electronic Theses and Dissertations
Models of resource exchange mutualisms utilize economic principles to explain how the costs and benefits of these interactions vary with environmental context. All of these models use a ratio of resource exchange (e.g., nitrogen: carbon) as the central variable, and it is unclear whether such exchange ratios predict outcomes of mutualisms in natural systems. Corrêa et al. (2008) hypothesized instead that the absolute flux of the most limiting nutrient, rather than the ratio of the two exchanged resources, best explains the benefits of resource exchange mutualisms. To distinguish between these two competing hypotheses, we measured resource transfers, and their ratios, …