Life Sciences Commons^™

Investigating Microbe-Plant Symbioses In Space, David Handy

Theses and Dissertations

As life has evolved on Earth, gravity has been a constant around which biological processes have developed, rather than a pressure that has been adapted to. As humanity ventures into space, we remove this constant and can observe a variety of changes in biological systems, such as bone loss in humans, stunted plant growth, or increased virulence in pathogens. The growing body of data shows that life adapts to spaceflight and microgravity in unique ways that, due to our limited understanding, can be difficult to predict. A particularly under-studied area is that of host-microbe interactions. Despite efforts to limit their …

Evaluating The Effects Of Cheatgrass On Western Burrowing Owls, Kaylee R. Draughon

Theses and Dissertations

There has been a global decline of specialist species observed in recent decades due to the impacts of climate change, invasive species, and habitat loss. Habitat loss and degradation may lead to a mismatch between habitat attractiveness and actual quality, otherwise known as an ecological trap. Ecological traps occur when an organism is constrained by its evolutionary past to select for cues that no longer accurately predict habitat quality. Specialist species are more susceptible to ecological traps due to greater reliance on and fidelity to historic sites and resources. The burrowing owl (Athene cunicularia), a specialist bird species adapted to …

Comparative Genomics Of Anax (Odonata: Aeshnidae), Ying Fei Lin

Theses and Dissertations

Insect migration is an important phenomenon characterized by the long-distance travel of various species in search of resources, safety, breeding, and/or suitable climates. However, relatively little is known about insect migration patterns and the genetic factors associated with them. Three closely related species of dragonflies (Odonata: Aeshnidae), Anax junius, A. strenuus, and A. walsinghami, form a clade of migratory and non-migratory species and present a natural laboratory to study the evolution of genes that may be related to muscle developments and insect migration. In this study, we sequence the whole genomes of these three Anax species to present a resource …

Chromosome-Scale Assemblies And A Pangenome Reveal Ltr Repeat Dynamics As A Major Driver Of Genome Evolution In Chenopodium, Kate E. Jaggi

Theses and Dissertations

The genus Chenopodium, which comprises around 150 species globally, is characterized by its wide geographic distribution and ecological adaptability, particularly in temperate regions. Some species, such as Chenopodium quinoa and Chenopodium pallidicaule, have served as domesticated staple crops in the Andean region of South America for centuries, valued for their robust nutritional profile and adaptability to adverse environmental conditions. In contrast, wild Chenopodium species exhibit broad geographic distributions and diverse niche adaptations, functioning as reservoirs for beneficial traits, including disease resistance and climate hardiness, essential for enhancing domesticated crops through introgression and breeding efforts. However, taxonomic classification within the genus …

Cytotoxicity, Antibacterial And Anti-Inflammatory Properties Of A Synthesized Curcumin Analog And One Of Its Novel Derivatives, Marian Amir

Theses and Dissertations

This research aims to describe the synthesis, characterization, and the biological response via investigating the cytotoxic activity, hypoxic microenvironment response, antibacterial, and anti-inflammatory properties of the novel curcumin analog H-4073 and its succinate derivative (H-4073 SuD) in the context of hepatocellular carcinoma (HCC). The study also aimed to compare the effects of H-4073 and H-4073 SuD to assess their relative efficacy and potential as therapeutic agents. First, the cytotoxic effects of H-4073 and H-4073 SuD were evaluated on HEPG2 cell lines under normal conditions. Results revealed that H-4073 exhibited a significantly better cytotoxic effect than H-4073 SuD in normoxia. However, …

Deciphering The Microbial Fingerprint Of Covid-19: A Multi-Layered Exploration Of The Oral And Gut Microbiome Dysbiosis, Iman Mostafa Sultan

Theses and Dissertations

The impact of SARS-CoV-2 infection on the human microbiome remains a dynamic and intricate puzzle. This study delves deeper into this mystery by revisiting the oral and gut microbial compositions of 53 COVID-19 patients before and after viral clearance, alongside comparisons to 76 healthy individuals. Through a comparative lens, we have emploed two distinct differential abundance methods – DeSeq2 and ANCOM – while drawing upon the thorough SILVA database encompassing the full-length 16S rRNA gene. The analysis underscores the crucial role of a diverse methodological choir in microbiome research. In certain instances, the congruence between DeSeq2 and ANCOM may exhibit …

Effect Of Plumbagin On Chemo-Resistant Metastatic Retinoblastoma, John J. Soto

Theses and Dissertations

Retinoblastoma, which is an ocular malignancy, usually results in poor prognoses in pediatric patients worldwide. Retinoblastoma in some events, can develop metastatic phenotypes which can lead to secondary tumor formation, furthering deleterious patient outcomes. It is of paramount importance to identify and research potent novel compounds that can be used to increase the likelihood of remission. Plumbagin (PLB) is a plant-derived, neuroprotective agent, which exhibits significant anticancer activities during in vitro study. PLB has been shown to have a high therapeutic efficacy against chemoresistant sublines as well as their normal counterparts. We attempted to show that the chemoresistant ABCC1 could …

A Study Assessing Stress Induction Methods And Regulation Genes, As Well As Cellular Ultrastructure And Automated Image Analysis In Synechocystis Sp. Pcc 6803, Rebekah White

Theses and Dissertations

In the world of microorganisms, cyanobacteria are a uniquely skilled powerhouse. They participate in global nutrient and carbon cycling. They can photosynthesize, which allows them to use sunlight and carbon dioxide to produce cellular energy. However, photosynthesis involves a lot of molecular interactions where environmental stresses can interfere, increasing the chances of oxidative stress and nutrient imbalances that can amplify deleterious effects. One such stress, iron limitation, is well-studied and its responses in the cell are known. This study assesses the differences between responses when induced by two different iron limitation methods. Then, a specific stress response regulator DspA, also …

Discovery Of Oligomeric States And Small Molecules That Affect Deacylase Activities Of Human Sirtuin-2 (Sirt2), Jie Yang

Theses and Dissertations

Human sirtuin isoform 2 (SIRT2) is an NAD+-dependent enzyme that removes various acyl modifications from lysine residues. SIRT2 is involved in many biological processes, such as transcription, DNA repair, cell proliferation, and metabolism. Due to its diverse functions, SIRT2 is implicated in various disease states, including cancers and neurodegenerative disorders. This dissertation aimed to understand the regulation of SIRT2’s deacylase activities and to discover small molecule modulators of SIRT2. In this work, we found that SIRT2 dimerized in solution, and the dimerization decreased the deacetylase activities without affecting the defatty-acylase activity of this protein. Dimerized SIRT2 dissociates into monomers upon …

Using Rna Sequencing Methodologies To Uncover Common Pathways In Neural Tube Defects: A Comparative Study Of Three Oxidative Neurotoxicants, Aubrey Coleen Johansen

Theses and Dissertations

Neural tube defects (NTDs) are the second most common type of congenital birth defect that affect infants worldwide. There are several proposed mechanisms for NTDs, but no definitive mechanism has yet been described. One possible mechanism is oxidative disruption of normal developmental signaling. The purpose of this study is to culture whole mouse embryos with three common developmental toxicants, mono-2-ethylhexyl phthalate (MEHP, a plastic pollutant), Fumonisin B1 (FB1, a corn mold), and valproic acid (VPA, an anticonvulsant drug), all of which are known to cause NTDs, and compare their shifts in redox potential and changes to important signaling pathways through …

Using Rapid Protein Degradation To Determine The Effect Of Runx1 Loss-Of- Function On Dna Damage Accumulation And Repair., Jackriel Pina Morales

Theses and Dissertations

Germline mutations in RUNX1 are associated with familial platelet disorder with a predisposition to myeloid malignancy (RUNX1-FPDMM), in which patients present with low platelet counts,excessive bleeding and bruising, and an increased risk of Acute Myeloid Leukemia (AML)/Myelodysplastic Syndrome (MDS) development throughout their lifetime. To understand how these loss-of-function mutations in RUNX1 drive predispose to malignancy, it is important to develop a detailed understanding of the molecular basis of RUNX1 function. While RUNX1 is a transcription factor, preliminary data from our group and work from others suggests that RUNX1 also interacts with proteins that are critical for DNA damage …

Investigating The Impact Of Climate Change On Evapotranspiration Using Modeling, Faten Waheed

Theses and Dissertations

The available water resources are at risk due to climate change and the increasing water demand. Evapotranspiration is a very important element in water cycle. Evapotranspiration is perceived as a linking mechanism between the surface of the land and the atmosphere. Therefore, investing appropriate approaches to estimate evapotranspiration and the implication of climate change on evapotranspiration and available water resources are of great importance for better water management and food security. Penman-Monteith (PM) equation is considered as one of the most widely used equation for estimating ETo. It is also one of the most complex energy balance equations requiring detailed …

Design And Implementation Of A Machine Learning Predictive Model For Crop Yield In Indoor Vertical Hydroponics Farming, Emna Bouzid

Theses and Dissertations

To optimize agricultural practices and address water scarcity, this work introduces Vertical Hydroponics and Machine Learning (ML) to smart agriculture, using data from Internet of Things (IoT) sensors to enhance crop production in low and medium-income countries, particularly Tunisia's, hydroponic farms. This research is an innovative approach to enhancing crop production within indoor vertical hydroponic systems by utilizing different ML predictive models and assessing their performance. This part was done at UALR while the data collection was done at MedTech, with 21 basil plants. This study compares Linear Regression, Long Short-Term Memory (LSTM), and Deep Neural Networks (DNN) for precision …

Fecal Genomics Provides Insights On Connectivity Of Endangered Wildlife In A Human Dominated Landscape, Abhinav Tyagi

Theses and Dissertations

Many mammalian species, facing severe historic range reductions, now inhabit fragmented habitats. Habitat fragmentation involves the reduction of habitat into smaller patches, increasing distances between them, and eventually leading to small isolated populations. Species' responses to habitat alteration may vary based on factors such as body size, dispersal ability, and abundance. Understanding these differences is crucial for effective multispecies conservation planning. Genomic data, within a landscape genetic framework, are increasingly applied to evaluate the effects of habitat fragmentation and understand influential landscape features for connectivity. The quantity of data enhances the power and precision of assessing landscape impacts on gene …

Investigating The Antibacterial And Immunomodulatory Effects Of Resolvin D2 On Monocytes And Macrophages, Cristina Maria Padovani

Theses and Dissertations

In the late phase of sepsis, immunosuppression occurs, where the host is unable to clear the pre-existing infection and is susceptible to secondary infections. It is believed that the ideal treatments for sepsis should attenuate immunosuppression so that the host can get back to homeostasis. Specialized Pro-resolving Mediators (SPMs) are endogenously- produced fatty acids that resolve infectious inflammation without being immunosuppressive. We hypothesize that an SPM – Resolvin D2 (RvD2) – can augment exhausted macrophage function during the immunosuppressive phase of sepsis. We developed a two-hit model to establish macrophage exhaustion in vitro, and found that RvD2 increased NF-κB activity, …

Anticipatory Behaviors And Vocal Expression In A Group Of Captive African Elephants (Loxodonta Africana), Matthew B. Rios

Theses and Dissertations

Animal vocalizations convey motivational and affective properties. Using passive acoustic monitoring and behavioral observations, this study investigated the relationship between vocal communication and anticipatory behaviors within a group of captive African elephants (Loxodonta africana) to inquire whether bioacoustic monitoring has the potential to be used for assessing captive animal welfare.

A Study Of The Effects Of An Amino Acid Residue On The Thermal Stability Of A Collagen Triple Helix In Varied Sequence Context, Ph, And Ionic Strength Of The Buffer, Zhenxun Xu

Theses and Dissertations

Collagen mimetic peptides are used broadly for collagen research and biomedical applications. Unlike the synthetic peptides obtained by solid phase chemical synthesis, recombinant peptides have more than 100 amino acid residues in length and are expressed in E. coli using designed genes. These longer peptides can offer improved, more native-like functions of native collagen for biomedical applications. One major challenge is the intrinsically low stability of native collagen, which has a melting temperature just above the physiological temperature of the organism. To understand how to enhance the thermostability of the peptides, I investigated the effects of amino acid sequences on …

Effect Of Short-Term Exposure To Pesticide Mixture On Tissue Architecture, Body Fluid Conditions, Nitrative Stress And Osmoregulation Of American Oyster, Crassostrea Virginica, Asif Ahmed

Theses and Dissertations

Pesticides are used widely to control weeds and pests in agricultural settings but harm non-target aquatic organisms. We examined the effect of short-term exposure (one week) to pesticide mixtures (low dose: 0.5 μg/L Roundup®, 0.5 μg/L 2,4-D, and 0.4 μg/L atrazine; high dose: 1 μg/L Roundup®, 1 μg/L 2,4-D, and 0.8 μg/L atrazine) on American oyster (Crassostrea virginica, an important shellfish and seafood species) under controlled laboratory conditions. Histological analyses demonstrated the atrophy in oysters' gills, digestive glands, and connective tissue. The protein concentrations and glucose levels dropped significantly in the high-dose treatment. The number of hemocytes in connective tissue …

Pipecolic Acid And Novel Insights Into Cerebral Malaria, Akua E. Mensah

Theses and Dissertations

Cerebral malaria (CM), a severe manifestation of Plasmodium infection, prompts our investigation into the nuanced role of pipecolic acid in its pathophysiology. To unravel the molecular intricacies, we conducted in vitro lysine labeling techniques of mice infected with P. berghei ANKA parasites, and human P. falciparum grown in vitro, aiming to discern the impact of Plasmodium on pipecolic acid production. Previous observations indicated an elevation in pipecolic acid levels correlating with neurological decline in children with CM. In our study, confirming elevated pipecolic acid presence in the plasma and brain tissues of CM patients and the animal model of CM, …

Investigating The Demise Of East Bank Ridge Through Local Fishery Perceptions And Fish Population Metrics, Marissa R. Lamb

Theses and Dissertations

East Bank Ridge is a natural reef formation located 18 nautical miles off the coast of South Padre Island, covering an area of over 80 km2, with the southern portion extending into Mexico. There is no previous record of the structural composition or fish community present at the site. The ridge was a well-known fishing site in the local community over the past decades but catch rates have decreased substantially according to personal accounts from local anglers. In this study, areas of reef habitat were identified, and fish presence and abundance metrics were determined at East Bank Ridge. These measures …

Genetics Of Lrg1 And Its Association With The Cardiometabolic Risk Traits In Mexican American Children And Adolescents, Aaron Rene Reyna

Theses and Dissertations

Leucine-rich alpha-2-glycoprotein 1 (LRG1) has become a major topic of research due to an increasing number of studies demonstrating its unique role in the pathogenesis of multiple human diseases including diabetes and cardiovascular disease. LRG1 has recently been identified as an adipokine, a signaling molecule secreted by adipose tissue. Furthermore, it has been correlated with intercellular signaling that promotes diet-induced hepatosteatosis and insulin resistance in mice. In this study, LRG1 serum concentrations were measured in a family-based cohort of 571 non-diabetic Mexican American children and adolescents aged 6-17 years old (mean age = 11.76 years and females = 48.2%) to …

Foxo4 Impacts Akt In Glioblastoma Multiforme, David Uribe

Theses and Dissertations

Glioblastoma Multiforme (GBM) is an aggressive cancer with patients surviving 13 months on average after diagnosis. The PI3K-PKB/AKT pathway is conserved from flies to mammals. The PI3K signaling pathway aids in the growth and survival of tumor cells. Forkhead box transcription factors subclass O (FOXO1, FOXO3, and FOXO4) act as tumor suppressors in some contexts. In GBM, our group and others showed that FOXO transcription factors drive stem gene expression to promote growth and survival. We disrupted the FOXO4 gene in U87MG cells using CRISPR Cas9 genome editing and performed RNA-seq to identify targets of this …

Development And Application Of Environmental Dna (Edna) Techniques To Detect Rough-Footed And Yellow Mud Turtles: A Seasonal Field Study To Detect Turtle Edna, Sakib Tahmid Rishan

Theses and Dissertations

The application of environmental DNA (eDNA) has improved the ability of humans to detect the existence and geographical distribution of aquatic organisms. The present study highlights the development and application of eDNA techniques to detect rough-footed mud turtles and yellow mud turtles in different areas in Texas. Both mud turtle species were successfully detected in lakes/resacas using direct eDNA sampling techniques. Moreover, passive eDNA sampling techniques were conducted using different membrane filters to detect mud turtle species. The findings indicated that only the mixed cellulose esters (MCE) filter membranes effectively identified eDNA of yellow mud turtles in the fall, but …

Effects Of Nitrogen Or Phosphorus Depletion On Lipid Production In Bracteacoccus Sp. And Tetrastrum Sp., Cassandra J. Po

Theses and Dissertations

As global energy demands have risen in the past decades, various species of microalgae have been chosen and used as sources of lipids for third-generation biofuel. I selected two species of green microalgae, Bracteacoccus sp. and Tetrastrum sp., from isolates from South Texas to determine their potential as sources of biofuel. For comparison, Chlamydomonas reinhardtii was used as a model organism. To evaluate lipid productivity under different nutrient regimens, the microalgae were grown in nutrient-replete growth media until the population had reached the end of the logarithmic phase (roughly 14 days), and then transferred into growth media depleted of nitrogen …

Role Of Interferon-Induced Protein With Tetratricopeptide Repeats 3 (Ifit3) In Hiv-1 Associated Neurodegenerative Disorder And Alzheimer’S Disease, Ranjit Kumar Das

Theses and Dissertations

The advent of cART has revolutionized the management of HIV-1 infection and saved the lives of millions of people worldwide. Yet, HAND continues to be clinically relevant with aging people with HIV-1 (PWH). The underlying mechanism of HAND remains poorly understood. In this regard. Signal transducer and activator of transcription 1(STAT1) and IFIT3 genes have been shown to induce neuroinflammation and neuronal cell death. However, the role of IFIT3 in HAND pathology has not been well established. Therefore, the present work investigated the significant role of IFIT3 gene in development of HAND. In the current study, …

Utilizing Nanodiamond For Antiretroviral Drug Delivery To Hiv Infected Microglial Cells, Ebenezer Owusu

Theses and Dissertations

Combination antiretroviral therapy (cART) is widely used to treat HIV infection, but it fails to eradicate viral reservoirs, such as microglia in the brain, leading to HIV-associated neurological disorders (HAND). Advances in nanomedicine have enabled the development of targeted drug delivery systems, and nanodiamonds (NDs) and fluorescent nanodiamonds (FNDs) have emerged as a potential solution due to their biocompatibility, non-toxic nature, and efficiency as drug carriers. Our study builds on previous findings that NDs can cross the blood-brain barrier (BBB), aiming to utilize NDs and FNDs for their added traceability. We propose a multifunctional nanodrug platform that leverages NDs and …

High Intraspecific Diversity Of Pocillopora Damicornis In Southeast Asia Reflects Adaptive Potential To Climate Change, Maria Lucille Carr

Theses and Dissertations

Marine heatwaves are increasing in intensity and frequency because of increased emissions of greenhouse gases. On coral reefs, warmer temperatures cause coral bleaching, mortality, and shifts in benthic composition. However, coral bleaching responses and survival vary geographically. Several hypotheses may explain such geographical differences in thermal tolerance, including the possibility that some localities may support higher intraspecific diversity than other localities, increasing the likelihood of survival of some individuals through heatwaves. Here we assessed geographic patterns of intraspecific genetic diversity in the ubiquitous coral Pocillopora damicornis. Intraspecific genetic diversity was assessed for 428 sequences across 44 sites in the Pacific …

Optimization Of Coral Restoration Along The Florida Reef Tract, Raymond Barry Banister

Theses and Dissertations

Historically, the reefs of Florida were dominated by two framework-building corals, Acropora cervicornis and A. palmata. However, these two populations have declined by 95% since the 1970s. The predominant contributors to the coral decline have been ocean warming and disease. In response to the decline, restoration organizations were established to improve survival, growth, and reproduction. Yet, there are gaps in current restoration practices and our knowledge of effective restoration techniques. This study uses large datasets to develop models that predict the most optimal locations for coral restoration in Florida and examines the relationships between the occurrence of wild acroporids …

Molecular Insights Of Paraoxonase 2 In Advanced Glycation End Product Induced Endothelial Dysfunction, Ramya R

Theses and Dissertations

Diabetes mellitus (DM) is a metabolic disorder associated with various vascular complications and affects the function of the endothelial cells. Elevated blood glucose levels accelerate the formation of advanced glycation end products (AGEs) by Amadori rearrangement and bind to their Receptor for the advanced glycation end product (RAGE) and evoke release of key pro-inflammatory cytokine proteins leading to endothelial dysfunction. Paraoxonase 2 (PON2) is an endogenous intracellular enzyme, localised in mitochondria, endoplasmic reticulum (ER), and nuclear membrane with numerous properties, like anti-inflammatory, anti-apoptotic and anti-oxidant.

Our present study aims to ascertain the effect of AGEs on PON2 activity and expression, …

Physical Activity, Cardiorespiratory Fitness And All-Cause Mortality, Jorin Dane Larsen

Theses and Dissertations

Introduction Both elevated levels of physical activity (PA) and high cardiorespiratory fitness (CRF) are associated with a decreased risk of all-cause mortality. The degree to which an individual's PA level and CRF status interact to influence mortality is not currently fully understood. This study investigated whether PA and CRF were independently related to all-cause mortality, and to what degree PA was associated with improved mortality risk in individuals with low CRF. Methods This is a prospective cohort study using health assessments on individuals gathered between 1975 and 2002. Health assessment data were matched with the National Death Registry to assess …