Digital Commons Network^™

Improving Restoration Success Of Winterfat: Influences Of Hydrophobic Seed Coatings And Planting Depth On Seedling Emergence, Kyle Andrew Cook

Theses and Dissertations

In western North America, winterfat (Krascheninnikovia lanata (Pursh) A. Meeuse & Smit) is a valuable protein-rich subshrub whose restoration has been limited by poor seed flowability and low rates of seedling establishment. Seed flowability can be limited by a dense covering of hairs on winterfat fruits that can cause them to clog in mechanized equipment. Seedling establishment can be limited by premature germination of fall-sown seeds that can cause over-winter seedling mortality from freezing, pathogen attack, and winter drought. Seed coatings may provide a way to overcome both of these barriers to winterfat restoration. Coatings can compress hairs against the …

Predictive Modeling The Impact Of Engineered Products In Dynamic Sociotechnical Systems: An Agent-Based Approach, Christopher S. Mabey

Theses and Dissertations

The impact of engineered products is a topic of increasing concern in society. The impact of a product can fall into the categories of economic, environmental, or social impact; the last category is defined as the effect of a product on the daily lives of people. Design teams lack sufficient tools to help improve the impact of products and understand the impact of products at scale in society. This dissertation aims to provide insight and methods for improving the social, environmental, and economic impact of engineered products. The majority of the research focuses on the prediction of product impacts on …

Experimental Evolution Under Varying Sex Ratio And Behavioral Plasticity In Response To Perceived Competitive Environment Independently Influence Male Cricket Calling Effort, Jack Thomas Mckermitt

Theses and Dissertations

The operational sex ratio (OSR) is a key component influencing the magnitude of sexual selection driving the evolution of male sexual traits, but males often also retain the ability to plastically modulate trait expression depending on the current environment. Here we employed an experimental evolution approach to determine whether the OSR affects the evolution of male calling effort in decorated crickets, a costly sexual trait, and whether plasticity in calling effort is altered by the OSR under which males have evolved. Calling effort of males from two selection regimes maintained at different OSRs over 18-20 generations (male- versus female-biased) was …

Understanding The Experiences Of Mothers Of Children With Stunting In Two Egyptian Communities Focusing On The First 1000 Days, Rana Abdelgawad

Theses and Dissertations

Introduction: Egypt’s stunting prevalence is 13% with multiple initiatives and programs tackling child malnutrition. While many of them are promising, not all address the child’s first 1000 days, in addition to missing the cultural aspect for the Egyptian population which affects their dietary practices and health seeking behaviors.

Goal: Determine what challenges mothers face for their child’s nutrition and what learnings from exemplars countries can help Egypt reduce the malnutrition and stunting problem

Aim: Finding insights about the factors influencing child nutrition during 1st 1000 days and what programs can be implemented based on successful past experiences in exemplar countries. …

Investigating Eco-Evolutionary Interactions Between Hosts And Members Of Their Gut Microbiota, Logan A. Sauers

Theses and Dissertations

Evolutionary and ecological interactions between hosts and their associated microbial communities, their microbiota, and between members of these communities are vital to understand. Microbial communities are widespread across diverse host taxa and hosts receive a variety of well-documented benefits from their microbial communities. Despite the importance of understanding eco-evolutionary dynamics for colonization outcomes and the benefits these communities provide to their hosts, our current knowledge in this area remains incomplete. For example, we do not know the full extent of coevolution and specific relationships between hosts and microbes, and between the microbes themselves, across host taxa. Questions remain about how …

Contingency Management For Opioid Use Disorder: Early Treatment Adherence And Mood, Shelby Renee Goodwin

Theses and Dissertations

Opioid use results in potentially devastating consequences, but medications for opioid use disorder, such as buprenorphine, serve as effective ways to curb cravings and withdrawal, helping an individual reduce their use. Unfortunately, around half of patients discontinue buprenorphine treatment within 30 days and co-occurring conditions such as mood symptoms may serve as additional barriers and decrease engagement. This study sought to examine contingency management (CM; incentives for meeting behavioral goals) as a potential intervention to increase early treatment engagement, as well as the role of total depression, anxiety, and stress (mood) severity in the efficacy of contingency management. New patients …

The Impact Of The Tobacco-Free Policy On The Auc New Cairo Campus, Fatimah Badawy

Theses and Dissertations

In 2019, the American University in Cairo (AUC) conducted a research study on campus attitudes towards tobacco use and smoking behaviors within their community, in light of the then newly enforced tobacco-free policy. They found most campus members in support of the policy, with higher rates of disapproval from the smoking community. In 2021, this research aimed to follow-up on changes in attitudes towards the policy as well was smoking behaviors. It hypothesized that over time, levels of support to the policy would increase, smoking habits would be positively impacted and that positive health behaviors would correlate with policy support. …

Development Of New Chemical Probes To Delineate The Polyamine Regulation & Molecular Strategies To Unravel Protein Polyamination, Vennela Tulluri

Theses and Dissertations

Polyamines such as putrescine, spermidine, and spermine modulate critical cellular processes, including gene expression and cell proliferation. Cellular polyamine regulation is a complex mechanism controlled by three different proteins: Ornithine decarboxylase (ODC), Antizyme (OAZ), and Antizyme Inhibitor (AZIN). While ODC is directly involved in polyamine biosynthesis, OAZ, and AZIN regulate the ODC activity via protein-protein interactions. The dysregulation of ODC, OAZ, and AZIN leads to elevated polyamines in numerous pathologies, making them attractive targets for controlling polyamine levels. Besides regulating polyamine synthesis, OAZ modulates polyamine transport. However, the precise mechanism remains elusive. In this research, we discuss our approach to …

Examining Food Insecurity Among Mississippi Community College Students, Laura Jean Kerr

Theses and Dissertations

Food insecurity among postsecondary students and especially community colleges is a persistent social problem, but the prevalence continues despite much research. Postsecondary students experience food insecurity slightly differently from the general population and they are held to different rules to qualify for food support such as the supplemental nutrition assistance program (SNAP). In this research I examine the prevalence, frequency, and duration of food insecurity experiences among Mississippi community college students. I begin with a discussion of the literature of food insecurity and policy used to address food insecurity. I draw upon Bourdieu’s theory of social fields, capital, and habitus …

Identification And Quantification Of Allelochemicals Associated With Weed Suppression In Sweetpotato, Varsha Varsha

Theses and Dissertations

Mississippi ranks among the leading states in sweetpotato production in the US. However, managing weeds in sweetpotato fields presents a significant challenge, and the limited availability of herbicides labeled for use in sweetpotato makes it even more challenging. The widespread and repeated use of herbicides has led to the development of weed resistance. In addition, herbicides are incompatible with the organic production system. Finding sustainable weed management strategies to provide weed control options for organic cultivation and detain the development of herbicide-resistant weeds under conventional crop production is imperative. The natural chemicals released by the plants, also called allelochemicals, can …

Development And Evaluation Of An Automated Tactical Tillage Tool To Control Weeds In Row-Crop Production Systems, Grace Mccormick Friday

Theses and Dissertations

Weed control is an integral part of a successful overall production strategy in row- cropping systems and has the potential to reduce or eliminate yield losses that negatively affect profitability. Timely and correctly selected herbicide applications are the major keys for effective weed control in a majority of instances. However, there are negative factors that contribute to ineffectiveness and weed escape issues that currently lack viable options for management. Sparsely populated late-season weeds that emerge after lay-by herbicide applications and weeds that have become tolerant and resistant to traditional herbicide chemistries are of greatest concern. Historically, these weeds would have …

Physiological And Proteomic Analysis Of Soybean In Response To Drought And Heat Stress, Amandeep Kaur

Theses and Dissertations

Drought and temperature stress are the two most important factors limiting crop productivity. A physiological and proteomic analysis of soybean was performed to investigate the negative impact of these variables. The previous studies reported the beneficial effect of silicon under stress conditions. Silicon supplementation may promote plant growth under drought stress, although the mechanism to alleviate drought stress is uncertain. The proteomic analysis of chloroplast proteins was carried out to study the response of silicon supplementation under drought stress.

Similarly, temperature stress, mainly heat stress, has an adverse effect on soybean plants. The comparative analysis of two soybean cultivars, DS25-1 …

The Consequences Of Low Energy Availability Related To Relative Energy Deficiency In Male Athletes: A Systematic Review, Lauryn Bailey

Theses and Dissertations

RED-S is a syndrome that stems from low energy availability (LEA) in athletes. It can impact numerous physiological and psychological functions, as well as negatively affect performance. Because RED-S is a relatively new syndrome, there are few studies showing the impact of RED-S on performance and physiological factors. The aim of this systematic review was to examine the consequences of induced LEA in relation to RED-S in male athletes. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, Five studies were deemed eligible based on inclusion and exclusion criteria. Studies measured risk of RED-S through body composition, bone …

Eating German, The American Way: German And American Cooking Traditions, Potato Salad, And The Culinary Assimilation Of German Immigrants, 1820-1920., Scott Wooley

Theses and Dissertations

“Eating German, the American Way” explores how and why the mayonnaise-based potato salad came to be a staple of American culinary tradition. It examines how native-born Americans and German immigrants in the nineteenth century identified themselves based on their culinary traditions and what they ate and how the interactions between, and accessibility of, those traditions created a new identity based on the sharing of recipes as the two groups mingled and assimilated to each other. It uses food as a way to understand the processes of assimilation by defining the distinctions between the two groups based on their separate repertoire …

Molecular Characterization Of Seminal Plasma From Boars With Divergent Sperm Quality, Notsile Hleliwe Dlamini

Theses and Dissertations

Seminal plasma (SP) is the microenvironment of spermatozoa whose composition reflects semen quality and constitutes an excellent source for detecting non-invasive biomarkers. This study characterizes good vs. poor quality semen using seminal extracellular vesicles coupled proteins and miRNA. Fresh boar semen samples were screened, centrifuged, and SP supernatants were collected for near-infrared spectroscopy (NIRS) analysis. EVs were extracted from SP (SP-EVs), characterized, and those of extremely poor or good sperm quality groups were subjected to proteomics and small RNA sequencing. Significant differences were set for P

Managing Iron Deficiency Chlorosis (Idc) In Soybean Through A Cropping System Approach, Katelin Savannah Waldrep

Theses and Dissertations

Iron deficiency chlorosis (IDC) is a frequent problem throughout many areas of the United States where soils are high in calcium carbonate (CaCO₃), including the Blackland Prairie regions of Mississippi. The main objectives of this study were to 1) determine the effects of seven different cropping systems on IDC visual symptomology and grain yield in rainfed soybeans grown in calcareous soils, and 2) evaluate the effects of soil water tension (SWT) on IDC. Rotating soybeans with corn produced significantly higher yields for both tolerant and susceptible soybean varieties. IDC symptomology was worse, and yields were lower in cropping …

Evaluation Of The Relationship Between Hair Coat Shedding Ability, Apparent Forage Digestibility, And Mineral Status In Angus Cattle, Margaret P. Loftin

Theses and Dissertations

The objective of this study was to evaluate the relationship between hair coat shedding ability, apparent forage digestibility, and mineral status in Angus cattle. Fecal samples were collected on fall calving Angus cows for one week in March, May, and July from 2019-2022. Liver and plasma samples were collected in March and July each year. Fecal samples were analyzed for DM, ash, NDF, and ADF while liver and plasma were analyzed for mineral concentration. Data were analyzed using MIXED procedure of SAS with significance declared at P0.05. Interactions were detected for DM, NDF, ADF, and liver Fe concentration. The model …

Impact Of Daily Sweet Potato Ingestion On Alterations To The Gut Microbiome, Cholesterol, And Exercise Performance, Johneric William Smith

Theses and Dissertations

The importance of the gut microbiome is being explored in relation to multiple facets of health and performance. The purpose of this study was to explore the impact of frequent sweet potato ingestion on alterations of the gut microbiome which might in turn alter cholesterol levels and exercise performance. Thirteen recreationally trained males had fecal and blood samples collected and exercised to fatigue with and without exogenous carbohydrate ingestion prior to and following 42 days of daily sweet potato ingestion. Bacterial communities were extracted from fecal samples and bacterial DNA were sequence. Blood samples were analyzed for total cholesterol, low-density …

Evaluation Of Nutrient Digestibility Of Weaned Calves From Early And Late Shedding Dams, Jennifer Keele

Theses and Dissertations

Researchers have investigated several factors that could alter fetal growth, including nutrient restriction (Valiente et al., 2021), hair shedding (Gray et al., 2011), and extreme hot and cold temperatures (Davidson et al., 2022). Hot temperatures and increased humidity percentages in the southeast United States caused researchers to investigate the hair coats of Angus cattle in the commercial production setting. An improvement in fiber digestibility and calf birth and weaning weights has been observed in Angus dams that shed 50% of the winter hair coat by May (Gray et al., 2011; Burnett et al., 2021). Our objective of this experiment was …

Experiences Of School Administrators And Teachers: Challenges And Promising Practices During The Covid-19 Pandemic, Helen Teresa Hyde Carter

Theses and Dissertations

This study examined the lived experiences of teachers and administrators as reflected in their responses regarding instructional materials, instructional delivery, social and emotional well-being of students, and access to critical school services during the COVID-19 pandemic. Participants shared their experiences about how the instructional materials and delivery modes were selected as well as the guidance and support given by school administrators. Major challenges and concerns along with promising practices related to student engagement, social and emotional well-being of students, and access to critical school services were identified.

The Neuroprotective Role Of Vitamin D In Humans With A Traumatic Brain Injury: A Systematic Review, Hailey Jarr

Theses and Dissertations

Traumatic brain injuries (TBI) are a leading cause of death worldwide. Previous research supports a relationship between vitamin D and TBI outcomes; however, they rely on animal studies. This review aimed to examine the neuroprotective role of vitamin D in humans with TBIs. A search was completed (PubMed and Scopus) following PRISMA guidelines to review publications investigating the relationship between vitamin D deficiency (VDD) and TBI or the effect of vitamin D supplementation on TBI outcomes; 8 studies were identified. Patients had the
/="/">following ranges: 26-88% deficiency and 62-88% insufficiency compared to 24% and 49% of the general population. …

Analysis Of Gene Evolution In The Long-Lived Heliconius Butterfly Genus, Leann Ward

Theses and Dissertations

The butterfly genus Heliconius has an unusually long lifespan (six to eight months compared to only several weeks) and the unique ability to feed on pollen. The additional amino acids provided by a pollen diet seem intrinsically tied to longer lifespan in Heliconius. Because of these traits, Heliconius may be a valuable model species for future aging studies. As a preliminary analysis, we investigated differences in gene evolution between Heliconius and seven short-lived butterflies. We observed that the Heliconius genes had significant differences in evolutionary rates, in the direction of selection, and in the amounts of site-specific positive selection compared …

The Effect Of Vitamin B-12 Supplementation On Visual Reaction Time In Young Adult Females, Sean M. Servalish

Theses and Dissertations

This study investigated the effect of vitamin B-12 supplementation on visual response time (VRT). Menstrual cycle phase (MCP) and 24-hour dietary intake of B-12 were also observed as dependent variables. This blind, placebo-controlled trial observed 14 young adult females in four treatment groups: control, 500mcg (low dose), 2000mcg (moderate dose), and 3000mcg (high dose). The study lasted 28 days, with participants treated weekly, randomly assigned to each of the treatment groups. When comparing B-12 dose treatment groups to VRT baseline, there was significant improvements in VRT. Compared to the placebo, there were no significant differences among treatment groups. Significant differences …

Roles Of Limestone Particle Size Ratios And Phytase Levels On Performance, Eggshell Quality, And Bone Health In Post-Peak And Late-Lay Single-Cycled W-36 Laying Hens, Charis Waters

Theses and Dissertations

The objective of this study was to investigate the role of fine (F) and coarse (C) limestone ratios and exogenous phytase at standard and superdosing activity on performance, egg quality, and bone quality of post-peak and late-lay Hy-Line W-36 hens. For post-peak, treatments with 40F:60C at 0 and 400 FTU/kg (standard phytase activity) increased hen-day egg production (HDEP). Treatments with 15F:85C decreased feed intake (FI) but also increased unsaleable eggs (UE) and eggshell-breaking strength (EBS). Treatments with 0 and 400 FTU/kg increased albumen quality and treatments with 1500 FTU/kg increased bone quality and phytate breakdown. For late-lay, interaction effects of …

Assessment Of Leguminous Cover Crops For Use In Saccharum, Dylan Mathis Hollowell

Theses and Dissertations

Cover crops play a part in improving sustainability by reducing negative environmental impacts such as soil erosion and nutrient runoff. Energycane could benefit from cover crops due to its row spacing. This study was conducted at the Bearden Dairy Research Center to determine differences in nitrogen accumulation, weed suppression, and energycane yield among treatments. Four cool-season species (planted in the fall of 2020 and 2021) [balansa clover (Trifolium michelianum), hairy vetch (Vicia villosa), white clover (T. repens) and winter pea (Pisum sativum subsp. arvense)], and four warm-season species (planted in the …

Remote Physiological Monitoring Of The Giant Panda And Red Panda Using Near Infrared Spectroscopy And Machine Learning, Qingyu Sheng

Theses and Dissertations

Appropriate conservation decisions and efforts must be based on real−time and accurate information about wildlife populations. However, it is extremely challenging to monitor the population demography and physiological traits of many threatened and secretive animal species through direct observation and capture. Near infrared spectroscopy (NIRS) has the potential to be a remote tool to address questions concerning wildlife physiology and demography by analyzing “signs” of animals without seeing or capturing them. In this dissertation, two species, the giant panda (Ailuropoda melanoleuca) and red panda (Ailurus fulgens) are used as a case study, to demonstrate NIRS’ feasibility …

Identifying Barriers To Data Use On U.S. Beef Cow-Calf Operations And Developing Solutions To Improve Cow-Calf Record-Keeping, William Isaac Jumper

Theses and Dissertations

Cattle health and production records (CHPR) are data collected by cattle producers and veterinarians in the form of measurements, observations, counts of events over time, and physiologic attributes that describe individual and group-level health and production. These data are useful to both veterinarians and cattle producers for making evidence-based decisions on cow-calf operations. Currently, there are no uniform, industry-wide methods of capturing and recording CHPR in the U.S. cow-calf industry. Although many cow-calf producers in the U.S. are thought to collect some form of CHPR, it is believed that relatively few are doing so in an electronic manner that facilitates …

Examining Physiological And Photosynthetic Effect Of Led Lighting On Lettuce And Kale Microgreens, James Travis Blanche

Theses and Dissertations

The objective of these studies was to observe the effects of LED lighting treatments on physiological parameters of lettuce and microgreens. Four different lighting treatments; 1) Physiospec (white), 2) Red, 3) DR9 (25:75 Blue:Red), and 4) Anthospec (at 20/80 Blue:Red); were used in this experiment. Two experiments were conducted: 1) Examining the effects of LED lights on lettuce yield and photosynthetic activity and 2) The effects of switching lighting regiments halfway through the growth cycle on Kale microgreen yield and color. Physiospec lighting was found to promote the highest yield and photosynthetic activity among the four treatments for lettuce. It …

Evolution And Epidemiology Of Channel Catfish Virus (Ccv), Arun Venugopalan

Theses and Dissertations

Channel catfish virus disease (CCVD) is the principal viral disease in the United States catfish industry. The CCVD is caused by channel catfish virus (CCV), with mortality reaching up to 100% in fingerlings. CCV is assigned taxonomically to the family Alloherpesviridae, genus Ictalurivirus, species Ictalurid herpesvirus 1 (IcHV-1). To date, virulence, immunogenicity, and genome plasticity of the CCV field isolates have not been investigated. Three genotypes of CCV (IcHV-1A, IcHV-1B, and BCAHV) were identified using restriction fragment length polymorphism (RFLP) analysis. Virulence assessment of three representative isolates of RFLP groups suggests that IcHV-1B (pooled survival [mean ± SE]: 58.3% ± …

The Influence Of Overwatering, Underwatering, And Waterlogging On The Growth Of Kale (Brassica Oleracea Var. Acephala), Skyler R. Brazel

Theses and Dissertations

The Intergovernmental Panel on Climate Change has predicted that there will be increases in precipitation and heat-induced drought events globally. Information on kale response to waterlogging is minimal. The purpose of this project was to identify the response of kale to three treatments of water stress: underwatering, overwatering, and waterlogging. Plant pigments analyzed displayed a varied response to underwatering and overwatering, with concentrations changing with maturity but with reductions and no changes, respectively, at full harvest maturity. Glucosinolate concentrations were also influenced by maturity and increased under waterlogging and underwatering but no differences with overwatering. Overall, water stress to any …