Digital Commons Network^™

Isolation And Characterization Of Bacteriophages From Fish Tank Samples, Oluwaseyi Oluwagbeminiyi Oladele-Ajose

Electronic Theses and Dissertations

Bacteriophages (phages) are viral obligate intracellular parasites that infect bacteria. Research has been carried out on alternative treatment plans for bacterial infections due to the increase in antibiotic resistance. Phages have been proposed as an alternative to antibiotics. This research focused on the isolation and characterization of bacteria from small aquariums. A total of 42 bacterial isolates were isolated from seven different fish tank water samples and were tested to determine if they possessed phages. Spot plaque assay revealed presence of lytic phage for only one of the isolated bacterial strains, which was determined to belong to Enterobacteriaceae family based …

Quantification Of Influential Surface Fuel Parameters In Fire-Prone Ecosystems Of The Netherlands, Lauren Lara

Electronic Theses and Dissertations

Changing climate conditions in northwest Europe present an increasing wildfire risk in the Netherlands. Focus on fuels monitoring in this region is not as extensive as it is in the United States. Accurate estimation of biomass fuel loading is integral to prevention of wildfires which pose a significant risk to both human lives and property. This research project attempted to create predictive models for three major fuel categories (litter/duff, shrub, and downed woody material). Reduction of the number of parameters to measure would streamline the process of fuel load estimation by reducing the number of measurements that need to be …

Molecular Detection And Characterization Of Rickettsia Sp. In Hard Ticks Collected In Nacogdoches, Texas, Haley Nicole Standifird

Electronic Theses and Dissertations

The number of cases of tick-borne diseases is increasing in the United States. Many efforts to control ticks have been made and are continuously being developed. These methods include surveillance of ticks and detection of the tick-borne pathogens.This study examined hard ticks in Nacogdoches, Texas, to test for the presence of Rickettsia sp. 47 ticks were collected from vegetation by flagging and their species, sex, and developmental stage were determined using available keys. Individual ticks were processed for nucleic acid extraction and molecular detection of Rickettsia sp. using PCR-based methods. The citrate cynthease gene, 17kDa gene, and outer membrane protein …

Characterization Of Molecular Content, Cytotoxicity, And Anti-Inflammatory Activity Of Extractions From Eupatorium Serotinum, Jordy Sloan

Electronic Theses and Dissertations

Inflammation is a complex and varied immune response which can be expressed chronically or as a temporary reaction to foreign invaders. Symptoms of inflammation include swelling, pain, soreness, and difficulty of motion. Recently, the effect of sesquiterpene lactones such as Helenalin from Arnica montana have been studied for their anti-inflammatory properties. In this study, we identified and harvested samples of Eupatorium serotinum, a plant historically used by Native Americans to treat a variety of medical illnesses. Crude extracts of the leaves, flowers, roots, and stems were prepared by ethanol extraction. The cytotoxicity of the different extracts on HEK293 cells …

Perception Of Alumni Of The Department Of Agriculture At Stephen F. Austin State University, Sherifat Rufai

Electronic Theses and Dissertations

University alumni surveys have served various purposes since they were introduced in the 1930s in the United States. The Department of Agriculture at Stephen F. Austin State University (SFASU) aimed to evaluate alumni perceptions between the Fall of 2010 and the Spring of 2022 to provide an opportunity to examine the relationship between degree fields and occupations and the agriculture curriculum, salaries, and demographic data for college graduates. This study's web-based survey was designed to include closed-ended and open-ended questions to collect individual opinions using Qualtrics Survey Software. The survey materials were made available on the alumni's social media accounts. …

Dolphin Behavioral Responses To Uncrewed Aerial Systems As A Function Of Exposure, Height, And Type, Savannah Damiano

Electronic Theses and Dissertations

Uncrewed aerial systems (UAS) are becoming a standard tool in the study of cetaceans, however, a comparative assessment of animal responses to UAS has not been established to gauge the most effective systems for cetacean study. We utilized Dolphin Quest Bermuda’s eleven bottlenose dolphins as subjects for such an investigation taking place over five weeks in 2022 and five weeks in 2023. The dolphins were evaluated for investigative behavioral responses to six off-the-shelf UAS types and a custom fixed wing system. Each UAS was flown in decreasing height vertically above the main dolphin lagoon to evaluate dolphin behavioral responses in …

The Future Is Now In Twisted Coil Polymer Actuators (Tcpa), Ryan Ronquillo

Electronic Theses and Dissertations

This thesis aimed to fabricate and test twisted coiled polymer actuators (TCPA) to understand the mechanical and thermal aspects of this artificial muscle fiber. The purpose of this thesis was to find a linear relationship using the LVDT sensor, fabricating TCPA fibers, and interpreting the data. The project tested whether nylon/polymer could be used as a better artificial muscle fiber.

This research accomplished three goals: (1) designing and fabricating a system capable of creating supercoiled muscle fibers consistently, (2) calibrating the Linear Variable Differential Transformer (LVDT) and Core, and (3) analyzing/interpreting the data of the Twisted Coiled Polymer Actuators (TCPA) …

Distribution And Soil Characteristics Associated With The Neches River Rose-Mallow (Hibiscus Dasycalyx), Morgan E. Langlinais

Electronic Theses and Dissertations

The Neches River rose-mallow, Hibiscus dasycalyx, is a rare herbaceous perennial endemic to East Texas. The threatened, obligate wetland species is currently at risk of being lost in the wild due to habitat loss, encroachment of nonnative and native plant species, and hybridization with two other Hibiscus congeners, Hibiscus laevis and Hibiscus moscheutos. Known locations of each of the three Hibiscus species were used to measure select soil characteristics and habitat variables associated with each of the rose-mallows. H. dasycalyx was concluded to be associated with more fertile soils and slightly more canopy coverage than H. laevis and …

Sequencing And Functional Characterization Of A Latrodectus Geometricus Defensin, Lg-Defensin, Jacklyn Victoria Thompson

Electronic Theses and Dissertations

Defensins are small, cysteine-rich, immune related proteins described to be the most widespread family of invertebrate antimicrobial peptides. Presently, there is limited information regarding spider defensins. In this study, a new defensin peptide was described in Latrodectus geometricus, Lg-defensin. The full open reading frame was resolved using RACE and de novo assembly, followed by a bioinformatical analysis and phylogenetic alignment to determine conserved sequence patterns and structural similarities to other defensins. Next, the functionality of Lg-defensin was determined using in vitro RNA interference to assess what impact silencing had on the spider’s ability to control a gram-positive and gram-negative bacterial …

Effects Of Prescribed Fire Regimes On White-Tailed Deer (Odocoileus Virginianus) Browse, Forage, And Nutrient Availability In The Pineywoods Ecoregion Of Texas, Wyatt L. Bagwell

Electronic Theses and Dissertations

Fire is a management tool for white-tailed deer (Odocoileus virginianus) habitat, influencing browse availability, herbaceous production, and nutrient content. In 2020 and 2021, this study utilized 46 plots across East Texas to assess these habitat components. A stem count index survey method was used to assess browse utilization prior to April in both years, and preferred browse species were clipped and analyzed for nutrient availability, and herbaceous production was also measured. Additionally, white-tailed deer population data, browse survey data, and recent fire history were obtained from five different wildlife management areas to examine their relationship. Deer had preferences …

The Effects Of Mindful Meditation On Body Image In Female Collegiate Athletes During The Late Luteal And Early Follicular Phases Of The Menstrual Cycle, Katherine Jankevicius

Electronic Theses and Dissertations

Body image has been studied in previous research but there is a gap in research with the consideration of body image changes during the phases of the menstrual cycle. The purpose of this study was to examine the effects of a mindful meditation intervention on body image during the late luteal and early follicular phases of the menstrual cycle in collegiate female athletes. Eight female collegiate athletes (age: 20.5 ± 1.8 years, height: 1.7 ± 0.1 m, weight: 62.4 ± 8.9 kg, body fat: 26.4 ± 6.9%) participated in both the control and mindful meditation intervention with each taking three …

Soil Quality Indicators And Vegetation Responses Following Ecological Restoration Thinning Of Ponderosa Pine On Three Soil Parent Material Types Under Grazing And Non-Grazing In Northern Arizona, Christopher Macdonald

Electronic Theses and Dissertations

This research was performed in a northern Arizona ponderosa pine (Pinus ponderosa P. & C., Lawson) forest. The objectives were to a) increase understanding of long-term vegetation responses to ecological restoration treatments on three soils types, with and without grazing, b) evaluate the responses soil physical, chemical, and biological properties to restoration treatments, with and without grazing, c) determine the utility of measured soil quality indicators to informing risks to sustainable soils management in southwestern ponderosa pine forests.

There were no significant differences in soil bulk density by soil type, treatment type, or grazing treatment. No significant differences …

Detection, Occupancy, Abundance, And Mercury Accumulation Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Texas, David Rosenbaum

Electronic Theses and Dissertations

Land use practices and physical alterations of ecosystems result in habitat loss and fragmentation, while chemical alterations, such as pollutant input, reduce habitat quality and health of exposed organisms. Here, I investigated the effects of watershed- and local-scale environmental variables on the occupancy, abundance, and mercury accumulation of a threatened aquatic species (Macrochelys temminckii, i.e., alligator snapping turtle) within the southwestern periphery of its distribution. Hierarchical modeling suggested the distribution of the species is more affected by watershed-scale land-cover than local habitat, and provided a baseline estimate of average species abundance across its range in eastern Texas. Abundance …

Assessing The Live Bait Industry And The Ecological Status Of Invasive Cyprinodontiformes (Sheepshead Minnow: Cyprinodon Variegatus And Gulf Killifish: Fundulus Grandis) In Texas Streams, Erin Shepta

Electronic Theses and Dissertations

The introduction of invasive species is one of the greatest threats to global biodiversity. Once established, invasive species often cause irreversible ecological damage on native communities. Here, I investigated the pathway of introduction and ecological impacts of the sheepshead minnow (C. variegatus) and the gulf killifish (F. grandis). Both species were thought to have been introduced into inland Texas waters via bait-bucket releases and have caused native populations of their inland congeners to decline. While I did not find evidence that either species were being sold in inland shops, bait industry experts did reveal other potentially …

Restoration Through Reassembly: Evaluating The Role Of Native Plants In Combatting Chinese Tallow, Olaniyi Ajala

Electronic Theses and Dissertations

Non-native, invasive species disrupt ecological processes and functions, posing a serious threat to natural ecosystems. By examining the growth metrics of the non-native, invasive tree, Chinese tallow (Triadica sebifera [L.] Roxb.), hereafter tallow, across different flooding and light regimes, I investigated how restructuring native communities with valuable native species will prevent the reestablishment of tallow. I studied the changes in morphological and physiological traits of tallow when growing with water tupelo (Nyssa aquatica L.), sugarberry (Celtis occidentalis L.), and green ash (Fraxinus pennsylvanica Marshall). I found that in the non-flooded and high irradiance treatments, tallow's growth …

Detection And Occurrence Of Nerodia Harteri (Serpentes: Colubridae) In An Upper Portion Of The Brazos River Watershed, Jessica Yates

Electronic Theses and Dissertations

Semiaquatic snakes are disproportionately impacted by habitat alteration adjacent to wetlands because of their reliance on both terrestrial and aquatic habitats. Brazos River Watersnakes, Nerodia harteri, are endemic natricines with one of the most restricted geographic ranges in North America. I quantified detection and site occupancy probabilities of N. harteri and its sympatric congeners (N. erythrogaster and N. rhombifer), as well as microhabitat selection within the Nerodia community. Within occupied transects, search effort was positively correlated with detecting N. harteri, whereas environmental and/or habitat variables were better predictors for detecting the sympatric congeners. Microhabitat selection between …

An Application Of Differential Mathematical Modeling Techniques To Study The Ongoing Rabies Epizootic In China, Christopher Turner

Electronic Theses and Dissertations

Rabies remains a global public health issue with a wide variety of neurological symptoms such as confusion, slight paralysis, hypersalivation, and hydrophobia. Rabies is usually fatal once symptoms appear. Many species are reservoirs for rabies, such as foxes, racoons, and wild dogs, which in turn can transmit the disease to humans, leading to complex transmission chains. There is a long latent period of rabies, between 1 to 3 months after infection, which further complicates control efforts. Mathematical modeling is a valuable tool in the study of infectious disease outbreaks and there have been many models applied to rabies outbreaks. However, …

Effect Of Mycorrhizae Inoculation On The Growth And Success Of Three Taxodium Distichum Hybrids In Saline - Impacted Coastal Soils, Elif Ilhan

Electronic Theses and Dissertations

In 2008, Galveston Island was severely impacted by Hurricane Ike, resulting in high salt deposition in the soil and groundwater. This caused a loss of many native plant species. A study was initiated to determine effective ways to promote the growth conditions of three bald cypress genotypes (Taxodium distichum var distichum and Taxodium distichum var mexicanum crosses) in salt-affected soils. The treatments applied were mycorrhizae inoculation, fertilizer application, and a combination of mycorrhizae inoculation and fertilizer application. A total of sixty (60) trees planted in plots of three rows and divided into five randomized replication blocks of four treatments …

Spatiotemporal Factors Affecting The Occupancy And Phenology Of A Declining Songbird (Bachman's Sparrow - Peucaea Aestivalis) At The Western Extent Of Its Range, Liam G. Wolff

Electronic Theses and Dissertations

The Bachman’s Sparrow (Peucaea aestivalis) is a declining songbird that occurs throughout the southeastern United States. Bachman’s Sparrow is a Species of Greatest Conservation Need in Texas, but information crucial to management efforts, such as factors affecting their detectability and occupancy, is lacking. I investigated the predictors of Bachman’s Sparrow occupancy and phenology in Texas using detections from autonomous recording units coupled with site characteristics and weather data. My results indicate that Bachman’s Sparrow occupancy is associated with increasing herbaceous ground cover and decreasing basal area, distance to the nearest source population, and basal area when canopy height …

Fish Community Assembly At Multiple Spatial Scales In East Texas Streams, Jake R. Swanson

Electronic Theses and Dissertations

Stream communities are structured by environmental processes that vary in strength across different spatiotemporal scales. Therefore, revealing how stream fish communities are influenced by environmental gradients may clarify how communities respond to disturbance associated with anthropogenic change. I investigated the relative role environmental variables play in the processes that structure the taxonomic and functional diversity of stream fish communities, as well as historical trends in occurrence and local habitat associated with a species of greatest conservation need within east Texas. The results of this study indicate that stream sites with more habitat complexity and stability support a more taxonomically and …

Double Consciousness And Unhealthy Weight Control Behaviors In Young Black And White Adults, Priscillia Ihionkhan

Electronic Theses and Dissertations

The present study examined the previously understudied notion that Black individuals are buffered against being dissatisfied with their bodies and in turn developing unhealthy eating and weight control behaviors. Double consciousness, a racially/ethnically sensitive measure of body dissatisfaction, was tested as a mediator of the relation between ethnic identity and unhealthy eating and weight control behaviors in Black and White adults. It was anticipated that unhealthy weight control behaviors would be more common in Black women compared to White women and that double consciousness would mediate the association between ethnic identity and unhealthy weight control behaviors among Black women, but …

Characterization Of Hemocytes In Amblyomma Americanum And Investigation Of Traf6’S Role In Proliferation Of Hemocytes In Response To Infection, Jacquelyn T. May

Electronic Theses and Dissertations

Amblyomma americanum is a medically important vector in the southeast United States. Cellular and molecular aspects of the immune system of this species were examined. To investigate cellular processes, hemocytes produced in response to gram-negative infection were characterized according to their ultrastructure. Four hemocyte types were identified: prohemocytes, plasmatocytes, type-I granulocytes, and type-II granulocytes. To elucidate molecular processes, we investigated AamTRAF as an immune-related gene by silencing the gene using RNAi then quantifying the hemocytes after inoculation with gram-negative and positive bacteria. It was found that silencing AamTRAF caused a decrease in hemocyte proliferation in response to gram-positive but not …

Economic Analysis Of Sunflower (Helianthus Annuus) Spacing In East Texas, Carly Wright

Electronic Theses and Dissertations

Two experiments were conducted on spacing of Helianthus annuus in East Texas to determine the spacing treatment that produces the greatest revenue per m². The experiments had four spacing treatments of 8 × 15 cm, 15 × 15 cm, 23 × 23 cm, and 30 × 30 cm. Three different cultivars were used in each experiment to determine if there was an interaction between spacing and cultivars. In both experiments, the stem height, stem diameter, flower diameter, and disk diameter increased as spacing increased. Also, as spacing increased, the days-to-harvest decreased. The 8 × 15 cm spacing produced …

Seasonal Flammability Comparisons Of Native And Exotic Plants In The Post Oak Savannah, Blackland Prairie, And Pineywoods Ecoregions Of Texas, Michael Tiller

Electronic Theses and Dissertations

East Texas’ diverse landscape can present year-round wildfire seasons that can be influenced by seasonal and regional differences in climate and physiography. Greater insight into the fundamental thermal behavior of wildland fuels can aid in fire behavior prediction and development of fire-resistant plant lists. This study focused on estimating seasonal and regional flammability characteristics of five evergreen species: yaupon (Ilex vomitoria), Chinese privet (Ligustrum sinense), greenbrier (Smilax spp.), eastern red cedar (Juniperus virginiana), and escarpment live oak (Quercus fusiformis); and two deciduous species: Chinese tallow (Triadica sebifera) and southern …

Natural Regeneration Dynamics And Survival Influenced By Abiotic And Biotic Factors In A Bottomland Hardwood Forest, Lydia J. Voth Rurup

Electronic Theses and Dissertations

Riparian ecosystems are vital to the landscape, providing critical services including water filtration and purification, flood and erosion control, carbon sequestration, biodiversity support, and aesthetic value. Bottomland hardwood forests, however, are threatened by invasive species, land loss/conversion, inconsistent or absence of harvesting disturbances, and altered hydrological patterns, leading to reduced success of desired, native species. This research assessed regeneration dynamics and one-year survival in a seasonally-flooded bottomland hardwood forest at Boggy Slough Conservation Area in East Texas to identify abiotic and biotic factors important for successful establishment of native regeneration. Areas sampled included two that were previously treated with herbicide …

Effects Of Varying Warmup Stimuli On Running Economy, Connor Bigenho

Electronic Theses and Dissertations

Purpose: The purpose of this study was to determine the effects of two potentiating warm-up stimuli (weighted-vest strides and plyometrics) on running economy (RE) over short (5-10 minutes) and longer durations (30+ minutes) of exercise in trained distance runners. Methods: Five recreationally trained male runners were recruited to participate in this study. Each trial consisted of a 10-min self-paced warm-up on the treadmill followed by baseline RE test and baseline leg-stiffness. This was immediately followed by one of two intervention warmup protocols. The protocols consisted of either a series of plyometric movements, 6 x 10-sec strides with a …

Assessing Freezing Effect On Kiwifruit Cultivars And Mapping Suitable Areas For Growing The Crop In Eastern Texas, Lais De Oliveira Machado

Electronic Theses and Dissertations

Kiwifruit is a perennial vine originating from China where it has been grown for centuries. In the United States, green kiwifruit (Actinidia deliciosa) is primarily produced commercially in California. They are fuzzy, green fleshed and well known in the marketplace. Kiwifruit plants require low to moderate soil pH, adequate winter chilling and adequate precipitation to guarantee plant development and good fructification. Actinidia chinesis or golden kiwifruit are smooth skinned, feature golden flesh and are a more recent introduction into the global market. Kiwifruit crops have attributes that favor production in east Texas, including low pest problems, current long …

Recovery Methodologies And High Intensity Interval Training, Blake W. Johnson, Malcom T. Whitehead

Electronic Theses and Dissertations

The purpose of this study was to determine recovery from Tabata bodyweight high intensity interval training (HIIT) exercise using different recovery assessment methodologies across 24- and 48-hour time intervals. Participants (23.2 ± 3.1 years old, 163.1 ± 19.9 lbs., and 22.8 ± 9.6 % body fat) consisted of 3 females and 7 males (n=10) Individuals who were recreationally trained (4+ days per week, 30+ minutes per day at moderate to vigorous intensity) and conducted both Trial A (24-hours between HIIT sessions) and Trial B (48-hours between HIIT sessions). Before and during each session, heart rate, countermovement jump, perceptual, …

The Effects Of Gibberellic Acid, Smoke Water, And Cold Stratification On The Germination Of Native Perennial Seed, Zyreasha Tippins

Electronic Theses and Dissertations

In this study, I evaluated the germination rates of twenty native plant species and their response to cold stratification as well as four chemical solution treatments—water (control), gibberellic acid, smoke water, and gibberellic acid with smoke water. Seeds were evaluated and counted twice a week. Of the twenty evaluated species, sixteen had germination rates over 3% or 1 seed out of 30. Stratification increased germination by 54% when compared to the control. For chemical treatments, gibberellic acid and gibberellic acid with smoke water were significantly different from the control and increased germination by an average of 47% and 48%, respectively. …

Deception Of Resistance And The Effects On Muscular Fitness And Perceived Exertion, Tyler Mchenry

Electronic Theses and Dissertations

Resistance training has been a popular tactic that individuals have used to increase muscular fitness for decades. Muscular fitness includes muscular endurance, strength, and power. However, limitations such as self-efficacy and the Central Governor Theory may influence individual maximal performance ability. One training tactic that has been rarely researched is the deception of resistance during exercise, which is assumed to increase performances in all aspects of muscular fitness and improvements in perceived effort. Inconsistent results have been concluded from previous studies that have examined the same topic. Therefore, the purpose of this study was to investigate the effect of resistance …