Life Sciences Commons^™

Non-Destructive Imaging Of Phytosulfokine Trafficking In Plants Using Fiber-Optic Fluorescence Microscopy, Bernard Abakah

Electronic Theses and Dissertations

Plants secrete peptide ligands and use receptor signaling to respond to stress and control development. Understanding these phenomena is key to improving plant health and productivity for food, fiber, and energy applications. Phytosulfokine (PSK), a sulfated peptide hormone, regulates plant cell division, growth, and stress tolerance via specific phytosulfokine receptors (PSKRs). This study uses fiber-optic fluorescence microscopy to elucidate trafficking of PSK in live plants. The microscope features two-color optics and an objective lens connected to a 1-m coherent imaging fiber mounted on either a conventional upright microscope body or 5-axis positioning system (X–Y–Z plus pitch and yaw). PSK and …

Ireland V. United States: Agricultural And Environmental Sustainability Policies, Lauryn O'Grady

Accounting Undergraduate Honors Theses

The United States and Ireland have varying practices to achieve similar objectives in regard to environmental sustainability. While the European Union has maintained and updated a uniform policy throughout its existence--the Common Agricultural Policy--the United States instead created short-term solutions to a long-term problem. Not only does the United States tend to solve issues in the short-term, the policies between agricultural production and environmental sustainability are not necessarily aligned or remotely relative to the other. While the United States’ new Global Food Security Strategy implements parts of both agricultural and environmental sustainability, much of the history was not based off …

Influence Of Cover Cropping And Nitrogen Fertilization On Soil Properties And Cotton Productivity, Christianah Oladoye

All Dissertations

Conservation practices with cover crops have proven to be effective in nutrient enrichment, increased yield, and environmental stability. Field studies were conducted from 2019 to 2022 to evaluate the short-term effect of No cover crop [NC], RYE, a mix of rye + vetch [R+V], and mix of five species (radish, rye, vetch, clover, and lupin) [5W] on short term soil physical, chemical properties, cotton growth, and lint yield. Cover crops were planted in November and terminated in May of each year. Soil dry and wet aggregate fractions (0-0.05 m) and soil compaction (0-0.4 m depth) were measured at termination. The …

An Integrative Approach To Modelling Human-Wildlife Coexistence Landscapes In The Northern Great Plains, Keifer Titus

All Dissertations

Restoring wildlife populations in a human dominated world requires a deep understanding of the ecological conditions required for species persistence as well as the human social factors that influence restoration outcomes. Until recently, the majority of prior research has focused on understanding the ecological conditions and human social processes that contribution to wildlife restoration success separately, and often assign a higher value to ecological factors. I studied the human dimensions surrounding ongoing wildlife restoration efforts in the Northern Great Plains (NGP) of Montana to better understand how human social factors can affect and inform restoration efforts for a variety of …

Developing A Cultural Management Approach To Bermudagrass Mite (Acari: Eriophyidae) Infestation, Matthew Brown

All Dissertations

Bermudagrass mite (Aceria cynodoniensis Sayed) (Acari: Eriophyidae) infestation stunts bermudagrass growth, leading to thinned turf and lower aesthetic and recreational value. Cultural management practices may impact bermudagrass mite infestation and turfgrass recovery from mite damage. Scalping or mowing shorter may physically remove mites, while drought stress may increase grass susceptibility to mites. Fertilizer application may promote mite infestation by improving plant nutrition. I conducted greenhouse, nursery, and field experiments to evaluate the impact of nitrogen fertility, irrigation rate, mowing height, and scalping on turf health and bermudagrass mite infestation in terms of the densities of witch’s brooms (i.e., stunted …

Acetate Metabolism In The Fungal Pathogen Cryptococcus Neoformans, Oly Ahmed

All Dissertations

Cryptococcus neoformans is an environmental basidiomycetous fungus with a worldwide distribution and a wide range of habitats. Inhalation of the desiccated yeasts or spores of C. neoformans often leads to opportunistic pulmonary infections in immunocompromised individuals, and in severe cases causes lethal meningitis following hematogenous dissemination. During infection, depending on the tissue and disease state, the invading fungi experience a range of nutrient microenvironments within the host body. As a result, rapid metabolic adaptations geared towards efficient utilization of carbon sources alternative to glucose become one of the prime determinants of survival and growth for the pathogen. Incidentally, cryptococcal infection …

Diagnosis Of Urinary Tract Infections And Rapid Molecular Characterization Of Antibiotic Resistance, Mohammed Harris

All Dissertations

Urinary tract infections (UTIs) are one of the most common infectious clinical entities in both community and hospital settings. They have a broad range of clinical severity yet inflict large epidemiological burden of morbidity and mortality on patients and the healthcare system with billions of dollars in cost of treatment. Understanding what methods are optimal for diagnosing UTIs are critical to mitigate the marked impact and cost of these infections.

Chapter 1 and 2 in this work surveys the broad array of diagnostic modalities for UTIs and highlights their advantages and limitations in the context of the current standard of …

Epidemiological Approaches For Practical Solutions To Pertinent Peanut Problems, Hope Becton

All Dissertations

Peanut is an important food crop grown in the southeastern region of the United States. Diseases are the most yield-limiting component in peanut production with one of the most important being late leaf spot (LLS), caused by Nothopassalora personata (Np). The disease initially appears in the lower canopy as dark brown to black lesions and conidiophores bearing conidia are produced on the abaxial side of the lesion. Np is passively dispersed primarily by wind and rain events. Spore traps were used to detect and quantify conidia captured up to 70 m from an inoculum source and to further assess …

Filth Flies As A Vector For Some Pathogenic Bacteria Transfer, Ahmet Buyukyavuz

All Dissertations

Two separate sets of experiments were conducted to determine the transfer of bacteria by flies. An Escherichia coli ampicillin-resistant strain with a fluorescent gene was used during the experiments. The first set of experiments were divided into two trials to measure the transfer of E. coli by fruit flies to apple slices and bologna during short term exposure. Short time exposure (1, 5 and 15 min) of flies to inoculated apple slices were tested in the first trial to determine the transfer of E. coli to flies. No difference (P>0.05) in the number of bacteria transferred to flies were …

Mitochondrial Roles In Developmentally Programmed Heart Disease, Eli John Louwagie

Dissertations and Theses

Offspring of diabetic and obese mothers (ODOM) have greater risks of heart disease at birth and later in life. However, prevention is hindered because underlying mechanisms are poorly understood. Mounting studies in the Developmental Origins of Health and Disease field suggest that mitochondria play key roles in developmentally programmed heart disease similar to the roles they play in cardiomyopathy in adults with diabetes and obesity. However, whether mitochondria are responsible for the short[1]and long-term cardiac disease seen in ODOM remains unknown. Here, we sought to delineate the roles of mitochondria in the hearts of ODOM, determine whether mitochondria are playing …

Effect Of Soy Co-Products In Supplements For Grazing Cattle On Growth, Complete Blood Cell Counts, And Physiological Response Following A Lipopolysaccharide Challenge, Bralee Lansdell

Biological Sciences Undergraduate Honors Theses

The objective of this study was to determine the effect of soy co-products (soybean meal and soy oil) in the diet on the growth and hemocytology of cattle during a 56-day growing phase and the physiological/behavioral response to an endotoxin challenge. Angus crossbred steers (n = 36; 289 ± 31 kg, initial body weight ± SD) were stratified by body weight and sire; and assigned randomly to pastures (n = 9; 0.45 ha/mixed-grass pasture). Pastures were assigned randomly to 1 of 3 dietary treatments: 1) a control supplement containing no soy co-products, 2) a supplement containing soybean meal, or 3) …

Early Life Stress Predicts Future Conduct Disorder In Adolescents, Savannah Ellis

Biological Sciences Undergraduate Honors Theses

Early Life Stress (ELS) and adversity increase people’s risk for developing mental, social, or emotional dysregulation and disorders later in life. The objective of this study was to test whether ELS in adolescents could prospectively predict future conduct disorder. The study additionally tested potential neural mediators of the effect of ELS on future conduct disorder, and specifically targeted the structural connections from the anterior insula and medial prefrontal cortex to the Nucleus Accumbens (NAcc). Data for the project came from the Adolescent Brain Cognitive Development Study (ABCD study), which is a longitudinal multi-site consortium funded by the National Institutes of …

Sex Differences In Host Resistance And Tolerance To The Common Avian Pathogen Mycoplasma Gallisepticum, Chloe Connelly

Biological Sciences Undergraduate Honors Theses

As we face the threat of global pandemics, one thing becomes clear: biological research is not just about the pursuit of the unknown, but about protecting our future. Understanding disease transmission and predicting pathogen epidemics is more important than ever. Prior studies have indicated that in populations where one sex engages in more social behaviors and movement that sex may drive disease transmission. This supports sex as a factor to consider in the study of epidemic dynamics. Host physiology and immune strategies are another factor that can influence epidemics. Two commonly examined strategies are tolerance and resistance. Tolerance is the …

Development Of Three Novel Edna Assays For Detecting Coastal Sharks, Kristina Dawn Flanigan

Electronic Theses and Dissertations

Environmental DNA (eDNA) analysis is an emerging, non-invasive community monitoring tool. This study aimed to determine if eDNA methods can be reliably used in a large brackish, partially mixed estuary by developing and testing three novel eDNA primers, for Sandbar Sharks (Carcharhinus plumbeus), Blacknose Sharks (Carcharhinus acronotus), and Bonnetheads (Sphyrna tiburo). These primers were designed to target 109, 156, and 120 base pair (bp) fragments, respectively, of the highly conserved NAD2 gene in the mitochondrial genome of each species. Primer function was validated through testing against 102 known genomic source samples and 25 filtered water samples from aquaria in which …

Past And Present Patterns Of Neutral And Adaptive Genetic Diversity In Wild Mandrills (Mandrillus Sphinx), Anna Weber

LSU New Orleans Theses and Dissertations

Although primates have fascinated researchers and the public alike for generations, one species that has remained enigmatic is the mandrill (Mandrillus sphinx), a large Cercopithecine monkey endemic to Central Africa. Mandrills are currently in decline due to bushmeat hunting, urbanization, and habitat loss. Neutral and adaptive genetic diversity are important tools for understanding evolutionary history and future viability, since diversity influences a species’ ability to adapt to a changing environment. However, thus far, minimal genetic information has been available for wild mandrills. Because of the dense vegetation in their tropical forest habitat, studying wild mandrills has proven to …

Therapeutic Approaches To Working With Perinatal Loss Clients: A Grounded Theory Study, Heather H. Olivier

LSU New Orleans Theses and Dissertations

Perinatal loss (i.e., miscarriage, stillbirth, termination, and infant death) is commonly referred to in the literature as an invisible loss, non-loss, and even medical event. It is an ambiguous loss exhibiting the dialectical contradiction between the physical absence and psychological presence of the baby accompanied by disenfranchised grief, a reaction to a loss that is unacknowledged by society. Despite the likelihood of mental health clinicians working with clients who have experienced perinatal loss, there has yet to be a therapeutic model designed specifically for the unique grief and trauma reactions presented in this population. Existing grief models do not address …

Complete Genome Sequences Of Evolutionary Clade C-Iii Strains Of Clostridioides (Clostridium) Difficile Isolated From The Environment In Western Australia, Nirajmohan Shivaperumal, Natasza M. R. Hain-Saunders, Barbara J. Chang, Thomas V. Riley, Daniel R. Knight

Research outputs 2022 to 2026

Clostridioides (Clostridium) difficile in the environment is thought to contribute to C. difficile infection in community settings. Here, we provide complete genome assemblies for two esculin hydrolysis-negative strains of C. difficile that were isolated from soils in Western Australia; the strains produce white colonies on chromogenic media and belong to evolutionarily divergent clade C-III.

Drivers Of White-Tailed Deer (Odocoileus Virginianus) Behavior, Survival, And Population Growth In The Piedmont Of South Carolina, Michael Muthersbaugh

All Dissertations

Prey species adjust behaviors in response to various stimuli, responding to both top-down and bottom-up pressures. Large herbivores must attempt to avoid predation either through adjusting behaviors or seeking spatial or temporal refugia, which can scale up to influence individual fitness and ultimately population dynamics. Specifically, predation risk has a great potential to influence ungulate populations by impacting behaviors and survival. Our objective was to quantify ungulate behavioral and population response to a regionally important predator through a case study – white-tailed deer (Odocoileus virginianus) responses to coyotes (Canis latrans) on private lands in the Piedmont …

Wild Sea Cucumber Trade In Rural Madagascar : Consequences For Conservation And Human Welfare, Emily L. Rothamel

Theses, Dissertations and Culminating Projects

Overexploitation of fisheries is a challenge to both marine conservation and human welfare. The trade of sea cucumbers is a multi-billion-dollar market, spanning over 70 countries. Global concern over unsustainable sea cucumber trade led to the inclusion of three species in CITES Appendix II, two of which are found in Madagascar (Holothuria fuscogilva and H. nobilis). I used 792 structured interviews (2015–2020) to study the intensity of sea cucumber collection and exportation in rural northeastern Madagascar, where 30% of all (terrestrial and aquatic) native species are threatened with extinction. Wild sea cucumber collection was common and increased tenfold during the …

Exploring Extreme Viruses With Ken Stedman, Kenneth Stedman

PDXPLORES Podcast

In this episode of PDXPLORES, Ken Stedman, Professor of Biology at Portland State University, discusses his distinguished virology career. From discovering his love of extreme viruses at Max Planck Institute for Biochemistry in Munich, Germany, to heading the Advanced Molecular and Cell Biology Research Laboratory and the eXtreme Virus Lab, Steadman has investigated extreme virus structures, function, genetics, and evolution for more than 25 years. He is the co-founder of the research lab Center for Life in Extreme Environments as well as the Chief Scientific Officer of StoneStable, Inc. Adding to his scientific accomplishments and accolades, Professor Stedman …

The Recruitment And Retention Of High School Sport Officials In Minnesota: An Exploratory Analysis, Zack Qual

Master of Science in Kinesiology

The issue that this proposal study will address is the current officiating shortage for Minnesota State High School League (MSHSL) sanctioned events. High school games are being rescheduled and at times canceled altogether due to the lack of available registered officials needed to ensure games are officiated correctly and with quality. In order to address this problem, the purpose of this proposed study will be to explore the types of interactions, both positive and negative, that registered MSHSL officials have had with players, coaches, and fans at events they have officiated. To gather the data, an online survey would be …

The Effect Of Running On The Onset And Development Of Osteoarthritis, Jordan Hekman

Senior Honors Theses

Osteoarthritis is a prominent and debilitating form of joint disease characterized by pain and deterioration of the articular cartilage and other tissues in the affected joint. Research has identified a variety of risk factors for osteoarthritis, including age, obesity, gender, previous injury, and occupation. The relationship between running and osteoarthritis is a topic of particular interest because of the prevalence of running as a simple and physiologically beneficial form of exercise. Increasing evidence suggests that recreational running has at worst no effect and at best a protective effect on joint and articular cartilage health in contrast to high-intensity professional/elite-level running …

Rattus Norvegicus As A Biological Detector Of Clandestine Remains And The Use Of Ultrasonic Vocalizations As A Locating Mechanism, Gabrielle M. Johnston

Master's Theses

In investigations, locating missing persons and clandestine remains are imperative. One way that first responder and police agencies can search for the remains is by using cadaver dogs as biological detectors. Cadaver dogs are typically used due to their olfactory sensitivity and ability to detect low concentrations of volatile organic compounds produced by biological remains. Cadaver dogs are typically chosen for their stamina, agility, and olfactory sensitivity. However, what is not taken into account often is the size of the animal and the expense of maintaining and training the animal. Cadaver dogs are typically large breeds that cannot fit in …

Phylogeny And Taxonomy Of Himerometroidea (Echinodermata: Crinoidea), Kristian H. Taylor, Gregory W. Rouse, Charles G. Messing

Marine & Environmental Sciences Faculty Articles

Himerometroidea is a clade of chiefly shallow-water, tropical, feather-star crinoids that is currently divided, based on morphology, into four families comprising 119 extant species in 31 genera. Our molecular phylogenetic results, based on three mitochondrial (CO1, 16S, CytB) and two nuclear (ITS and 28S) markers for 55 accepted species in 23 of the extant genera, allow for six clades within Himerometroidea to be given family ranks. Maximum parsimony, maximum likelihood, and Bayesian inference analyses recovered largely congruent topologies with varying nodal support. A new classification revises generic placements among five families: Himerometridae, Colobometridae, and Mariametridae, all retained, and Pontiometridae and …

Glycolytic Inhibitors As Leads For Drug Discovery In The Pathogenic Free-Living Amoebae, Jillian Milanes

All Dissertations

The free-living amoeba, Naegleria fowleri, can cause a rare yet usually lethal infection of the brain called primary amebic meningoencephalitis. Because of poor diagnostics and limited treatment options, the mortality rate associated with the disease is >97%. Due to our finding that glucose is critical for trophozoite growth in culture, we have been interested in exploiting amoebae glucose metabolism to identify new potential drug targets. We have characterized the first enzyme of the glycolytic pathway, glucokinase (Glck), from N. fowleri and two other pathogenic free-living amoeba, Acanthamoeba castellanii and Balamuthia mandrillaris. We have assessed their biochemical properties and …

The G Protein-Coupled Receptor (Gpcr) Fshr-1 And The Sphk-1 Lipid Kinase Regulate C. Elegans Life- And Healthspans Via A Common Pathway, Ryan Dennis Adkins

Undergraduate Honors Thesis Collection

Later years of life are often characterized by reduced cognitive function and mobility. One contributor is the cellular accumulation of reactive oxygen species (ROS), but our understanding of how cells respond to ROS to promote health and survival is incomplete. Follicle stimulating hormone receptor-1 (FSHR-1) and sphingosine kinase-1 (SPHK-1) mediate responses to oxidative stress and regulate life history traits in the roundworm Caenorhabditis elegans. The genes encoding both proteins are conserved in humans where they are implicated in stress responses, cell survival and neuronal function. fshr-1 and sphk-1 work together to mediate responses to intestinal oxidative stress in C. elegans. …

Sand Escarpments As A Potential Barrier To The Nesting Distribution Of Sea Turtles, Dakota Ronco

Undergraduate University Honors Capstones

Sea turtles are a part of both the marine and terrestrial ecosystems as primary and secondary consumers. By laying nests on the beaches and migrating across the ocean, sea turtles are significant in maintaining the nutrient (nitrogen and phosphorus) flux between terrestrial and marine ecosystems. Nests bring nutrients into the sand by decomposing unhatched eggs and egg remains. The distribution of their nests is significant in getting insights into the population density of sea turtles and what drives the nesting location, which ultimately regulates nutrient flux. The location of their nests is driven by sandy beach ecosystem structures, especially active …

Facebook In County 4-H Extension Programs In Arkansas: Is It Effective For Communication?, Haley Padgett

Graduate Theses and Dissertations

As social media rises in popularity, agents with 4-H responsibilities have the opportunity to implement social media platforms in their communication outreach. The purpose of this study was to identify how agents with 4-H responsibilities in Arkansas use Facebook for communication purposes and their perceptions of its effectiveness. This information helps provide understanding of the effects of Facebook on county 4-H programs in Arkansas and assists agents in determining how to implement or better utilize Facebook in their county programs. The study had three research objectives: 1) describe the usage of Facebook by agents in Arkansas with at least a …

Relationships Between Horizontal And Vertical Movements Of Shortfin Mako Sharks (Isurus Oxyrinchus) In The Western North Atlantic Ocean, Katie Gheysen

Senior Honors Projects

Highly mobile pelagic predators, such as tuna, swordfish, and sharks, often undergo changes in depth over a 24-h period and exhibit diel vertical migration (DVM), presumably to maximize foraging efficiency. Studies on the diving behavior of shortfin mako sharks (Isurus oxyrinchus) have been inconclusive as to whether this species consistently exhibits DVM. We investigated relationships between horizontal and vertical movements in shortfin mako sharks by using location and depth data collected from SPLASH tags and pop-up satellite archival tags (PSAT). A state-space model was applied to location data derived from SPLASH tags to generate continuous tracks and to …

Evaluation Of Landowner Perceptions Of Participating In Conservation Easements In The Beaver Lake And Illinois River Watersheds: Motivators And Barriers, Lauren Gwaltney

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Conservation easements (CEs) are an effective way to protect natural resources with minimal impact on the daily activities of landowners (LOs), but there is still resistance to CE adoption among landowners in Northwest Arkansas and Northeast Oklahoma. Therefore, there is a need to characterize LOs’ perceptions of CEs in these regions and adjust easement organization programming accordingly. This study followed a non-experimental, exploratory survey research design to gather information regarding demographics, awareness, attitudes, and preferences of LOs in the Beaver Lake and Illinois River watersheds. Likert-scale survey responses were assigned numerical values and averaged to find Pearson correlation coefficients between …