Digital Commons Network^™

Synthesis Of Yaku'amide A Analogues And Progress Toward Synthesis Of Virosine A, Alexander S. Ramos

Theses and Dissertations

The first project in this dissertation endeavors to outline the total synthesis of yaku'amide A and its analogs. Yaku'amide A is a natural product comprised of dehydroamino acids, including E-dehydro isoleucine, and unprecedented Z-dehydro isoleucine. These amino acids present a significant challenge to their synthesis owing to their unsymmetrical nature. To simplify the synthesis process, we synthesized analogs by substituting the E and Z dehydroamino acids with symmetrical subunits. This substitution facilitated the synthesis process and enabled us to obtain a similar three-dimensional structure to that of the natural product. Furthermore, biological testing of the simplified analogs revealed potency similar …

An Assessment Of Sentencing Disparities By Race In The State Of Arkansas, Viola Schaeffer

Theses and Dissertations

Past research has found that there are often disparities in sentencing outcomes due to extralegal factors such as race, gender, age, socioeconomic status, education level, and geographic location. The most prominent and widely studied of these factors, however, is race. Specifically, studies have shown that minority offenders (e.g., African Americans) were more likely to receive a lengthier sentence than their White peers. The purpose of this thesis is thus to examine if there is racial bias in sentences levied to violent offenders in Arkansas. This is be done by analyzing sentencing data from the Arkansas Office of the Courts between …

An Assessment Of Loblolly Pine (Pinus Taeda L.) Mortality And The Impact Of Habitat Fragmentation On Southern Pine Beetle (Dendroctonus Frontalis Zimmerman) Infestation In Mississippi, Usa, Damilola M. Taiwo

Theses and Dissertations

This thesis has two data chapters that consider factors affecting loblolly pine health in localized regions of Mississippi. The first data chapter investigated the abiotic and biotic factors contributing to loblolly pine (Pinus taeda) mortality on private timberland in Mississippi. This assessment considered temperature and precipitation variations, bark beetle populations, foliar and root pathogen tests, and drone survey. The results revealed that the loblolly pine mortality resulted from combination of factors. The second data chapter examined the impact of habitat fragmentation on southern pine beetle (SPB; Dendroctonus frontalis) infestation in Homochitto National Forest (HNF). This was assessed through remote sensing …

Investigating The Impact Of Transcription On Mutation Rates, Sarah Patterson

Theses and Dissertations

tRNA genes are highly transcribed and perform one of the most fundamental cellular functions. Although a universal pattern observed across all three domains of life is that highly transcribed genes tend to evolve slowly, tRNA genes have been shown previously to evolve rapidly. This rapid sequence evolution could result from relaxed selection, increased mutation rate, or a combination of both. Here, we use mutation-accumulation line sequencing data to show that tRNA genes accumulate more mutations than other gene types. Our results indicate that this elevated mutation rate is a consequence of both elevated transcription-associated mutagenesis and a lack of transcription-coupled …

The Development Of A Young Adults Cancer Patient Peer Match Application, Mojde Kalantari

Theses and Dissertations

This thesis explores the challenges and needs of young adult cancer patients, along with potential online resources to aid them, that includes social media, public and private organizations, and mobile applications. The focus of this research narrows down to communication and social networking mobile applications, particularly those with peer matching features. Although there are only three social apps in this category, a comprehensive analysis was undertaken. The research aims to underscore the need for a dedicated mobile application that connects young adult cancer patients with the same diagnosis. In response to this need, a mobile app named "YA Peer Match" …

A Tunable System For High Frequency Bioimpedance Plethysmography, Daniel H. Tebbs

Theses and Dissertations

Bioimpedance measurements are useful for determining a variety of biological conditions. By accounting for small impedance variations due to the arterial pulse, the effect of the blood can be studied more closely. The quasi-circulator system presented enables monitoring of pulsatile impedance changes with input frequencies above 1 MHz. The adjustable Rmatch allows for dynamic tuning of the system to increase sensitivity. By tuning Rmatch to be near the match point, the pulsatile signal in the output magnitude can be amplified, and tuning Rmatch to be at the match point causes the pulsatile signal in the output phase to be amplified. …

Dynamic Segmental Kinematics Of The Lumbar Spine During Diagnostic Movements, Paul Mcmullin

Theses and Dissertations

While lumbar kinematics can be measured in vivo, most measurements are invasive (such as percutaneous bone pins), provide high doses of radiation (such as biplane fluoroscopy), or are taken with the patient in a static position (such as MRIs). Recent work suggests that lumbar kinematics can be determined by dynamic measurements of epidermal strain in the lower back. This work aims to develop and examine a method of examining lumbar kinematics via optoelectronic motion capture utilizing skin-mounted markers in the lumbar region. Two studies were performed. One study examined lumbar epidermal strain in 28 asymptomatic subjects during diagnostic movements, while …

Designing An Artificial Immune Inspired Intrusion Detection System, William Hosier Anderson

Theses and Dissertations

The domain of Intrusion Detection Systems (IDS) has witnessed growing interest in recent years due to the escalating threats posed by cyberattacks. As Internet of Things (IoT) becomes increasingly integrated into our every day lives, we widen our attack surface and expose more of our personal lives to risk. In the same way the Human Immune System (HIS) safeguards our physical self, a similar solution is needed to safeguard our digital self. This thesis presents the Artificial Immune inspired Intrusion Detection System (AIS-IDS), an IDS modeled after the HIS. This thesis proposes an architecture for AIS-IDS, instantiates an AIS-IDS model …

Exploring The Impact Of Extracurricular Activities On Adolescent Development: A Study Of Students Attending Schools In Poverty And Non-Poverty Areas, Clifton B. Thames

Theses and Dissertations

Previous literature has indicated a relationship between poverty, participation in extracurricular activities, and developmental outcomes. The current study aimed to investigate and develop a deeper understanding of extracurricular activities (ECAs) and their impacts on adolescent development using two self-report tools, the YES 2.0 and the Delinquent Attitude Scale (DAS). The researcher surveyed 174 high school seniors from students attending schools in poverty areas and students attending schools not located in poverty areas in Mississippi, examining disparities in ECA opportunities, barriers to participation, and the positive and negative impacts of ECAs on development. Additional data were collected from school administrators, allowing …

The Effects Of Intermittent Fasting On Female Athletes: A Systematic Review, Courtnie Scarbrough

Theses and Dissertations

The intermittent fasting diet has a historical past, but recently, it has regained popularity as a weight loss strategy for the general public. Athletes have also picked up this specialized diet in search of a competitive edge. There are ample studies testing athletes of all levels, but most do not include females or report sex-specific results. This systematic review aimed to identify current research on the effects of intermittent fasting in the understudied population of female athletes. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a comprehensive search was conducted in three databases, including PubMed, Cochrane, …

A Thematic Analysis Of Religious Identity And Volunteer Motivation Among Emerging Adult Members Of The Church Of Jesus Christ Of Latter-Day Saints, Jennifer R. Smith

Theses and Dissertations

This study sought insight into the religious and cultural identity of emerging adults belonging to the Church of Jesus Christ of latter-day Saints(LDS) and the impact such identity had in relation to volunteering motivation. Participants included 24 emerging adult college students belonging to the Church. Thematic analysis was used to determine influencing factors that led to Church membership and how Church membership shaped self-perception. Participants shared volunteer experiences and motivation to volunteer in relation to Deci and Ryan’s (2000) self-determination theory (SDT) was examined. The motivation of relatedness was identified among 100% of participants as compared to competence (37.5%) and …

Hypothalamic Manipulation Of The Anuran Hpg Axis: Alternative Hormones And A Non-Invasive Administration Route For Amphibian Assisted Reproductive Technologies (Art), Erin Michelle Saylor

Theses and Dissertations

Amidst the amphibian extinction crisis, in situ and ex situ amphibian species conservation initiatives utilize assisted reproductive technologies for optimal genetic management of captive and wild populations. Development of effective, simple, low-cost methods for obtaining gametes for artificial fertilization, sperm biobanking, or natural breeding alleviates obstacles for institutions or programs to apply reproductive technologies. Objectives herein include investigating the efficacy of alternative hormones for inducing spermiation, an alternative hormone administration route for inducing ovulation, exploring the physiological effects of hormone therapy, and utilizing sperm from deceased animals for biobanking.

Development Of An Automated Delivery System To Apply Copper Sulfate Crystals Using Precision Dry Fertilizer Application Technology, Kevin Charles Wise

Theses and Dissertations

The digenetic trematode, Bolbophorus damnificus, poses a substantial threat to catfish aquaculture, causing significant economic losses. Infestations lead to suppressed feed consumption, secondary bacterial infections and poor production performance. Survey data reveals widespread infestation in the in the southeastern United States. Current control strategies involve the application of a concentrated copper sulfate solution to reduce snail populations which serve as the first intermediate host of the trematode life cycle. This study aimed to improve treatment efficacy by developing a granular copper sulfate application system. A modified Gandy fertilizer applicator, equipped with a programmable control system, demonstrated accurate distribution of copper …

Sign-Symmetry And Frustration Index In Signed Graphs, Abdulaziz Alotaibi

Theses and Dissertations

A graph in which every edge is labeled positive or negative is called a signed graph. We determine the number of ways to sign the edges of the McGee graph with exactly two negative edges up to switching isomorphism. We characterize signed graphs that are both sign-symmetric and have a frustration index of 1. We prove some results about which signed graphs on complete multipartite graphs have frustration indices 2 and 3. In the final part, we derive the relationship between the frustration index and the number of parts in a sign-symmetric signed graph on complete multipartite graphs.

Evaluation Of Cultivar Susceptibility And In-Furrow Fungicide Efficacy For Management Of Southern Blight Of Soybean, Adam Joseph Connor

Theses and Dissertations

Southern Blight (SB), caused by the fungus Athelia rolfsii, has increasingly impacted Mississippi soybean production with estimated economic losses in recent years rising from $181,616 in 2016 to $9,508,412 in 2021. Currently, there are no recommended fungicides and no known commercially available cultivar resistance. Eleven cultivars were evaluated for their response to the presence of Athelia rolfsii in the 2021 field trial. An in vitro fungicide assay was conducted to evaluate the efficacy of five fungicides to determine the respective EC50. These fungicides were then evaluated in combination with three cultivars, one mild, one moderate, and one severe in the …

The Impact Of Prior Pandemic Planning On Health Outcomes During The Covid-19 Pandemic: A Study Of Local Government Pandemic Planning In The United States, Karissa D. Bergene

Theses and Dissertations

In late 2019, scientists discovered a novel strain of coronavirus originating out of Wuhan, China. By January 2020, the United States (U.S.) saw its first positive case of coronavirus and the public was still unsure how serious of an epidemic this would be. By the time the World Health Organization declared the novel coronavirus disease (COVID-19) epidemic a “global pandemic” on March 11, 2020, world leaders, public health experts, scientists, and public administrators kicked into high gear to start serious pandemic response efforts. The public sector is typically the responsible authority for the preparedness, response, mitigation, and recovery of such …

Stream Water Quality Under Baseflow Conditions In A Livestock Production Area, Maryi Lorena Chavarro Chaux

Theses and Dissertations

This study evaluates the spatial and temporal impacts of implemented Best Management Practices (BMP) on stream water quality under baseflow conditions in a stream segment affected by livestock production. The BMPs includes 10-m fenced riparian zone and crossing paths along the reach segment. Grab water samples and water quality monitoring were collected biweekly from July 2019 to March 2022. Water quality parameters included temperature, dissolved oxygen, electric conductance, total dissolved solids, turbidity, and pH. Water samples were lab analyzed for sediments and nutrients. Results evidenced poor water quality before BMPs implementation, with nutrient concentrations exceeding the nation's and state's criteria. …

Advancing Salamander Conservation Efforts In Zoos And Aquaria Through Assisted Reproductive Technologies (Art), Devin Marie Chen

Theses and Dissertations

Salamanders are one of the most at-risk taxa in the world due to habitat destruction, pollution, climate change, invasive diseases, and more. This has led to a need for conservation breeding programs that are often associated with zoos and aquaria. Salamanders can be difficult to breed in captivity, though, due to their dependence on specific environmental cues and other unknown factors that stimulate sperm and egg production. To overcome these challenges, assisted reproductive technologies (ART) such as exogenous hormone administration, sperm cryopreservation, and in-vitro fertilization have been developed to increase offspring propagation and maintain genetic diversity. If genetically robust populations …

A Conceptual Decentralized Identity Solution For State Government, Martin Duclos

Theses and Dissertations

In recent years, state governments, exemplified by Mississippi, have significantly expanded their online service offerings to reduce costs and improve efficiency. However, this shift has led to challenges in managing digital identities effectively, with multiple fragmented solutions in use. This paper proposes a Self-Sovereign Identity (SSI) framework based on distributed ledger technology. SSI grants individuals control over their digital identities, enhancing privacy and security without relying on a centralized authority. The contributions of this research include increased efficiency, improved privacy and security, enhanced user satisfaction, and reduced costs in state government digital identity management. The paper provides background on digital …

Factors In Depopulation Trends Among Young Adults In Rural Areas In Mississippi, Katherine H. Ellard

Theses and Dissertations

The purpose of this study was to determine why young adults are leaving rural Mississippi towns and not returning to those areas. Research objectives were to 1) describe the characteristics of young adults who have left rural areas in the last ten years , 2) identify specific reasons why young adults choose to leave where they were raised, and 3) identify factors that would attract young people to return to rural areas in Mississippi.

Findings from this study indicated young adults were leaving rural areas for better educational and job opportunities, but some were relocating to other areas within Mississippi …

The Influence Of At-Planting Insecticide Treatments On Tobacco Thrips, (Thysanoptera:Thripidae), And Reniform Nematode, (Tylenchida:Hoplolaimidae), In Conventional And Thryvon Cotton Systems, Walker Brett Farmer

Theses and Dissertations

One of the objectives of this research was to evaluate the need for an additional imidacloprid seed treatment on ThryvOn^® (Bayer Crop Science^®, St. Louis, MO) cotton to effectively manage tobacco thrips, Frankliniella fusca (Hinds). While evaluating thrips densities and damage ratings, ThryvOn cotton continued to display reduced damage and thrips populations than non-ThryvOn. Thrips populations and damage ratings were consistently reduced when incorporating a higher rate of imidacloprid, but they were not reduced enough to justify the higher rates of imidacloprid. Another objective of this research was to evaluate the impact of aldicarb (AgLogic Chemical^{® …}

Design, Development, And Validation Of A Perfusion-Compression Bioreactor To Study Osteogenesis In Bone Explants, Alexis Victoria Graham

Theses and Dissertations

The current gold standard treatment for bone defects is autologous cancellous bone graft, which involves increased surgery time and donor site morbidity, and limited supply of bone and cells for regeneration. Bioreactors may aid in the generation of mechanically conditioned bone grafts with more cells compared to traditional grafts. However, the specific parameters of fluid flow and mechanical loading which contribute to osteogenesis and cell viability in bioreactors are not fully characterized. Here, a perfusion-compression bioreactor system was developed to study osteogenesis in porcine trabecular bone explants. Loading accuracy was over 88% across six bioreactors at a 0.1 s-1 strain …

Does Mississippi School Principals’ Age, Race, Gender, Educational Attainment, Work Experience In Education, Or Evaluation Scores Influence Accountability Points?, Braxton Dywayne Stowe

Theses and Dissertations

Traditional research agrees that only effective school principals can fully influence student achievement, and school leaders are pivotal to the success of schools in America. Researchers have linked positive student outcomes to further illustrate the point, including student achievement, to high-quality school leadership. The purpose of this study is to assist state and district education leaders in Mississippi in having a more profound knowledge of which principal demographics and characteristics are more directly correlated with the improvement of accountability scores or student achievement. The results of the correlational and regression analysis to determine the relationship between principal variables and the …

The Migration Ecology Of North American Turkey Vultures Wintering In The Neotropics: Spatial And Population Dynamics, Adrián José Naveda-Rodríguez

Theses and Dissertations

The spatial and population dynamics of avian scavengers are poorly understood. This information is key for management and conservation interventions that guarantee long-term species conservation. My goal in this dissertation is to fill information gaps on the movement ecology of New World vultures using the Turkey Vulture (Cathartes aura) as a model species. I used a continental-wide satellite telemetry dataset to study the migration ecology, space-use, and demography of the three North American breeding populations of Turkey Vultures wintering in the Neotropics during a 17-year period. I found that primary productivity, but not weather, triggered Turkey Vulture migratory …

Habitat Utilization Of Marsh And Adjacent Submerged Landscape By Fish And Macroinvertebrates In A Gulf Of Mexico Tidal Oligohaline Environment, Tia Offner

Theses and Dissertations

Estuarine habitats are considered nursery habitats for fishes and invertebrates, but oligohaline environments are critically understudied. Using a seine net and fyke nets, we sampled Back Bay, Mississippi (USA), a low salinity estuary, once a month for a year to explore the temporal use of the marsh and adjacent submerged landscape by nekton species. We also looked at whether there is evidence of habitat preference in the most numerous nekton species. We used a novel habitat usage index (HUI) to compare seine and fyke net catches of our top 10 species, and evaluated catch size in relation to maturation size. …

Assessing The Relationship Between Soil Health/Quality And Water Quality In The Mississippi Delta, Laura Andrea Sarmiento Rodriguez

Theses and Dissertations

Several studies have reported agronomic benefits by improving soil health/quality, but uncertain knowledge remains when determining specific impacts on water quality off-field. This study investigated the links between runoff water quality and soil health/quality in agricultural fields of the Mississippi delta under three land management scenarios: Conservation Reserve Program (CRP), vegetative buffer (VB), and row crops (RC). Using the Soil Management Assessment Framework (SMAF), a Soil Quality Index (SQI) was obtained based on ten soil health/quality indicators from 2008 and 2012 datasets. The SMAF identified significant differences in soil health/quality improvements among scenarios over a four-year period. Varied relationships between …

Current And Future Perceived Needs And Concerns For Older Adults Aging In Place In Mississippi: Intergenerational Perspectives, Muhammad Riaz

Theses and Dissertations

The study's purpose was to identify the perceived needs and concerns of three generations in a family with an older adult aging in place in Mississippi. This mixed-methods study used snowball sampling in addition to recruitment by community leaders such as Extension agents to collect data through semi-structured interviews and structured questionnaires that asked about current and future problems among aging adults in rural communities in Mississippi. Three generations of Mississippians participated in the study, including older adults (G1; n = 22), adult children (G2; n = 23), and young adult grandchildren (G3; n = 19). Quantitative data were analyzed …

Evaluating Teachers’ Perceptions Of The Social Validity Of Psychological Report Writing Styles, Adam Weseloh

Theses and Dissertations

Psychologists spend a significant portion of their time writing psychological reports. Oftentimes these reports are highly technical and written at a level which the literature has suggested is often difficult for teachers to utilize in their classrooms. Several previous research studies have examined psychological report writing practices and offered suggestions for improvement. One of these suggestions (theme or referral-based report writing) has not been as thoroughly examined in the literature. The purpose of this study was to examine this report writing style compared to more traditional report writing practices. This study utilized a novel approach to assessing teachers’ perceptions of …

Advancements In Time Resolved Spectroscopy And Nonlinear Microscopy, Bryan Semon

Theses and Dissertations

Non-linear optical processes such as coherent anti-Stokes Raman scattering and sum frequency generation offer a view into the chemical and biological interactions of molecules that is distinctly different from linear techniques like near infra-red and fluorescence. This insight comes at a cost: non-linear techniques are more sensitive to external perturbations of the system, increasing the noise and decreasing the repeatability of the data. We work here on both aspects of these non-linear techniques, taking advantage of their power to offer new imaging techniques as well as working to quantify and reduce the non-resonant noise inherent to the system. In pursuit …

Probing The Biophysical Interactions Between Autolysin Proteins And Polystyrene Surfaces, Radha Paramee Wadduwage

Theses and Dissertations

Biofilms formed on medical devices pose significant challenges, compromising device efficiency and serving as sources of infection. Staphylococcus epidermidis, an opportunistic pathogen, relies on the autolysin protein, notably its R2ab and amidase domains, to attach to polystyrene surfaces and initiate biofilm formation. Despite their pivotal role, the structural intricacies of these proteins’ interactions with surfaces remain elusive. In this dissertation, the multifaceted aspects of protein interactions with polystyrene surfaces and the implications of these interactions for biofilm control are studied. Over the course of this study, it is found how the R2ab and amidase domains influence biofilm formation on polystyrene …