Digital Commons Network^™

Laying-Sequence Variation In Yolk Carotenoids Of Eastern Bluebirds, Jessica Barkhouse

Theses and Dissertations

Carotenoids are naturally occurring, fat-soluble pigments that play an important role in the embryonic development of songbirds. Female songbirds use different strategies to allocate these important maternal resources to their eggs. Little research has been done on whether North American songbirds exhibit laying sequence patterns in their allocation of carotenoids. We studied the laying-sequence variation in yolk carotenoids and egg metrics of nine full clutches of Eastern Bluebirds (Sialia sialis) in Columbus, Georgia. I predicted that Eastern Bluebirds would exhibit a brood reduction strategy, with the first-laid eggs containing a higher concentration of carotenoids than the last-laid eggs. …

Recombinant Expression Of Preptin Analogs For Alanine Scanning Mutagenesis Of Residues 27-29, Tehgan N. Anguilm

Theses and Dissertations

The novel peptide preptin consists of 34 amino acid residues corresponding to Asp⁶⁹-Leu¹⁰² of proinsulin-like growth factor E-peptide. Preptin has been isolated from pancreatic beta cells, and it has been found to exhibit both metabolic and mitogenic activities. This makes preptin an attractive candidate to treat insulin-independent diabetes and osteoporosis. Alanine scanning mutagenesis was utilized to substitute an alanine for residues Trp²⁷, Arg²⁸, and Gln²⁹ of preptin in order to ultimately study the structure-activity relationship of these residues to preptin’s metabolic activity.

Connecting To History Through Service-Learning: A Qualitative Case Study Investigating Student Engagement In Core History Courses, Kimberly D. Stokes

Theses and Dissertations

Surveys have shown that students are not enthusiastic about taking history in college; some describe the discipline as boring and unnecessary. College is a setting where students are investing in themselves, exploring new knowledge to build a career, and gaining insight into the person they want to become in the future. Learning history through a traditional lecture method where memorization of names, dates, and events seems to be the norm is not appealing to students. Universities, promoting the thought that a well-rounded education is beneficial, commonly add history to the collection of general education core courses that are required for …

Evaluating Seed Blended Refugia In Field Corn In The Southern U. S., Tyler Breck Towles

Theses and Dissertations

Helicoverpa zea (Boddie), a pest of cotton that also occurs in field corn, is commonly controlled through the use of foliar-applied insecticides or transgenic crops expressing Bt genes. To prevent the selection of resistant populations, refuge systems have been implemented into the agroecosystem. Historically, structured refuge compliance among growers has been low, leading to the commercialization of seed blended refugia. To test the viability of seed blended refugia in the southern U.S., field studies were conducted in Mississippi and Georgia during the 2016, 2017, and 2018 growing seasons. To quantify adult H. zea emergence from structured and seed blended refuge …

Effects Of Dietary Lysine Restriction On Nutrient Metabolism And Muscle Gene Expression In Young Growing Pigs, Md Shamimul Hasan

Theses and Dissertations

The objectives of this project were to investigate the effects of dietary lysine restriction on (1) the plasma concentrations of selected metabolites, free AAs, and three growth-related hormones, (2) the gene expression profile in longissimus dorsi muscle growing pigs. Twelve individually penned young barrows (Yorkshire × Landrace; 22.6 ± 2.04 kg) were randomly assigned to two dietary treatments (a lysine-deficient, LDD, and a lysineequate, LAD) diets, respectively. Pigs had ad libitum access to water and their respective diets for 8 weeks, and the ADG, ADFI, and G:F were determined. At the end of the trial, jugular vein blood was collected, …

Assessment Of Social Media Technical Support Efforts For Extension Agents, Mary Annabelle Stokes

Theses and Dissertations

Extension agents are tasked with disseminating educational content, announcing events, and promoting the outreach efforts of Extension. Social media can be a powerful resource for Extension agents (Skrabut, 2014). Integrating social media into outreach efforts can be an efficient way for agents to meet increasing work demands (Gharis & Hightower, 2017). Still, many Extension agents are not fully integrating social media as a means to communicate with their audiences (Garcia et al., 2018). To address this, Extension communication units are developing social media technical support efforts to increase the agents’ social media activity (Garcia et al., 2018, Newbury et al., …

Agronomic And Physiological Responses Of Resistant And Susceptible Cotton Genotypes To Reniform Nematode Severity And Soil Nitrogen, Bhupinder Singh

Theses and Dissertations

Rotylenchulus reniformis (RN) nematode infection has been identified as a major biotic factor limiting cotton yield (~8%) in Mississippi. Cotton researchers are striving to develop resistance to RN and develop management practices to mitigate the problem. Reniform nematode and soil nitrogen (N) directly affect cotton growth and physiology, however, responses to RN and N may vary across a wide genetic background. The overall objective of this research was to determine the role that host plant resistance to reniform nematode and soil nitrogen plays in cotton growth, physiology, and yield and controlling RN populations. In experiment 1, the effect of RN …

Modeling Frameworks To Evaluate Energy Autarky Of Wastewater Treatment Systems, Gideon Sarpong

Theses and Dissertations

This research demonstrates the use of two novel methodologies to evaluate energy autarky status of wastewater treatment plants (WWTPs) in two steps. Step I (analysis 1 and 2) focuses on overall energy performance evaluation of a conventional activated sludge process (CAS) using a quantitative mass balance model. Step II involves development of a dynamic model that simulates a future wastewater resource recovery facility (WRRF). The step I (analysis 1) focused on small WWTPs with treatment capacities less than 5 MGD. The results revealed that a CAS process can achieve energy autarky or energy-positive status when old technology equipment is replaced …

Factors Associated With Quality Of Life And Dialysis Compliance, Viviana Garcia Guerra

Theses and Dissertations

This dissertation study explored the relationship between quality of life (QoL) and dialysis compliance with family support, spirituality, age, gender, and socioeconomic status (SES) among people with end stage renal disease (ESRD). Utilizing the Biopsychosocial Spiritual Framework, this study pursued to inform mental health professionals working with people undergoing dialysis about the factors that influence QoL and dialysis compliance. This descriptive quantitative dissertation study included 79 participants who self-identified as persons receiving either hemodialysis or peritoneal dialysis. Participants were members from closed social online forums and the National Kidney Foundation.

The current study found that family support and SES predicted …

The Romantic Cyclic Sonata As A Hidden Counterculture : Rethinking The Subdominant Through A Structural-Hermeneutic Approach, Marcelo Gabriel Rebuffi

Theses and Dissertations

No abstract provided.

Exploring Interactions Of Phyllosphere Epiphytes With Plant Pathogenic Bacteria Pseudomonas And Xanthomonas On Tomato, Ashley D. Turner

Theses and Dissertations

Recent studies have indicated the importance of resident microflora of plants in contributing towards overall plant health. Among difference components of the plant microbiome, Methylobacterium and Sphingomonas have been recognized as common residents of the phyllosphere for many host plants, however their role in disease control needs to be further investigated. The purpose of this study was to conduct experiments investigating the effectiveness of phyllosphere Methylobacterium and Sphingomonas isolated from red clover against common tomato phyllosphere bacterial pathogens, Pseudomonas syringae pv. tomato and Xanthomonas perforans. Additionally, this study uses X. perforans wild-type and X. perforans type VI secretion system …

The Effects Of Salvia Hispanica On Biochemical Markers Related To Immune System, Hormone Regulation, And Lumbar Vertebrae In Postmenopausal Rat Model, Daisy M. Mendez

Theses and Dissertations

In women, with age and menopause there is increase in body weight and decreased immunity and bone mass. Due to severe side effects of currently available drugs for obesity and bone loss, new therapies with less side effects are sought after and alternative medications are becoming more popular. Recently, Salvia hispanica (SH), a herbal supplement is implicated in losing body weight. Currently, there is no information on how SH modulates obesity or bone health. In this study, effects of SH seed extract was investigated in a postmenopausal rat model on certain hormones, immune markers, and fourth lumbar vertebrae. The highest …

Detection And Enumeration Of Bacterial Pathogens In The American Oyster (Crassostrea Virginica), Mohammad Maruf Billah

Theses and Dissertations

American oyster (Crassostrea virginica) is a popular seafood for its delicacy and high nutritional value. Based on increasing concern about contamination of bacterial pathogens in raw oyster, my research objectives have been focused on detection and enumeration of two important bacterial pathogens, Escherichia coli and Salmonella spp. in the American oyster in south Texas waters, local markets and controlled laboratory studies. Immunohistochemical and RT-PCR analyses showed substantial bacterial pathogen’s presence in gills and digestive glands of oysters collected from San Martin Lake and South Padre Island as well as local markets. Laboratory studies showed increasing trend of both …

Factors That Contribute To Social Emotional Competence In Early Childhood And Parental Resilience, Jackeline Guillon

Theses and Dissertations

This study examined the effect gender, family income, maternal education and parental resilience have on the social emotional competence of children attending a childcare facility in the Rio Grande Valley. Identifying factors that are specifically linked to child social emotional competence may inform decisions about how to implement effective preschool programs for children. Until recently, the literature on social emotional competence has been limited and mostly focused on a child’s early life experiences and parenting behaviors. A quantitative design utilizing multiple regression analysis was used to test the null hypothesis in this study. The data was collected using the procedures …

Organizational Effects Of Exogenous Corticosterone On Vocal Development In A Wild Parrot, Rory Eggleston

Theses and Dissertations

Songbirds learn songs during a plastic phase in vocal development, similar to human vocal babbling. Research has focused on male song learning, a process influenced by gonadal steroids. Like humans, parrots are very plastic vocal learners and both sexes learn vocalizations throughout life. It is unclear how the endocrine system mediates environmental information with developing phenotypes in parrots. Corticosterone (CORT) is a sex-neutral hormone that can affect cognitive development, but its role in vocal development has not been experimentally tested in wild parrots. I quantified vocal babbling from nestling Green-rumped Parrotlets (Forpus passerinus) recorded in Venezuela. Nestlings received oral CORT-oil …

Effects Of Arbuscular Mycorrhizal Fungi (Amf) On Growth And Herbivore Defenses In Sorghum Sudangrass (Sorghum X Drummondii), Jasleen Kaur

Theses and Dissertations

Chapter 2: In this chapter we have examined the role of trichomes in plant stress biology, reviewed the studies on herbivore X trichome interactions, and their role in plant defences. Ultimately, we have proposed new areas of research for future work.

Chapter 3: In this chapter, we examined whether AMF has cascading effects on insect community dynamics through attraction/repulsion of beneficial and damaging insects using Sorghum-sudangrass (Sorghum x drummondii), either inoculated with commercial AMF mix or left as control in lab and field experiments. Our results suggest positive effects of AMF on plant growth, and a lower initial incidence of …

Microgravity Emergency Medical Containment System – A Concept Of Architecture, Prototyping, And Usability Research, Keith Elliott Crisman

Theses and Dissertations

Exploration is intrinsic to human nature but is well understood to be accompanied by inherent risks to the explorer. This is particularly evident in the exploration of extreme environments such as long-duration space habitation; in which risk is increased due in particular to the distance from assistance, services, and replenishment of consumables. One of the major risks to extreme environment survivability is lack of access to emergency medical care. This risk is further amplified in the microgravity environment where terrestrial non-life-threatening conditions can become life threatening due to lack of next-level-care capabilities. The question posed within this research asks, ‘What …

Symbiosis And Immunity At The Tri-Kingdom Interface, Stephen Alexander Lazar

Theses and Dissertations

The rise in global sea-surface temperatures drastically and adversely impacts coral reefs worldwide through coral bleaching, diseases, and subsequent coral mortality. Corals become bleached by the expulsion of endo-symbiotic dinoflagellates, which reduces host pigmentation. Coral bleaching can also lead to enhanced disease prevalence immediately after thermal-stress and during the associated re-uptake of symbiotic dinoflagellates. This aspect has yet to be thoroughly investigated. A model system is necessary to study the relationships between symbiosis and disease that has sufficient flexibility to include a variety of host symbionts as well as pathogens. For this dissertation project, Exaiptasia pallida was investigated as a …

Effects Of Incubation Temperature On Nanomechanical Properties Of Β-Lactoglobulin Amyloid Fibers, Santosh Khatri

Theses and Dissertations

Amyloid fibrils constitute a class of highly ordered nanomaterials formed by aggregates of the protein. Although The irreversible fibril formation of various proteins is related to the disorders like Alzheimer’s diseases, Creutzfeldt-Jacob and many more, amyloid fibrils have also been noticed in many physiologically beneficial roles such as in adhesive and hormone storage. Here, we compare the stiffness and structural properties of the amyloid fibers examined by the statistical approaches of single molecule atomic force microscopy images of heat-denatured β-lactoglobulin fibrils at different incubation time period (24, 48, and 72 hours). We demonstrate the gradual decrease in stiffness of the …

The Past, Present, And Future Of Ecological Climate Warming Experiments, Cori Johanna Speights

Theses and Dissertations

Predicting the net effect of climate change on communities requires understanding how increasing temperatures alter interactions between predators, herbivores, and plants. Over the last several decades, warming experiments have provided important information about how species and their interactions will respond to increasing temperatures. These studies typically examine climate warming by experimentally increasing temperature at a constant level (24 hours) or asynchronously during the daytime, relative to unwarmed control treatments. However, advances in climate models now project that increases in mean global temperatures have been disproportionately driven by increasing nighttime (minimum) temperatures rather than daytime (maximum) temperatures. The timing of warming …

Refinement And Validation Of Soybean Looper (Chrysodeixis Includens) (Walker) Thresholds In Mississippi Soybeans (Glycine Max (L.) Merr.), Mary Huff

Theses and Dissertations

Experiments were conducted to refine and validate the soybean looper, Chrysodeixis includens (Walker) threshold in Mississippi soybeans, Glycine max. (L.) Merr. Equivalencies between sweep net and drop cloth sampling methods were evaluated, overall the sweep net was more effective at capturing soybean looper larvae greater than third instar and larvae less than or equal to third instar when compared to the drop cloth method. Feeding studies were conducted to determine the feeding rates of each instar, results showed that fifth instar larvae consume the greatest amount of leaf tissue, and larvae greater than or equal to third instar consume more …

Sedentary Behavior Levels And Patterns In Men And Women With Intellectual Disability, Supreete Ghosh

Theses and Dissertations

Background: Adults with Intellectual Disability (ID) experience health disparities that may be attributable to high sedentary behavior (SB). The levels and patterns of SB among U.S. adults with ID have received little attention. Purpose: To examine levels and patterns of SB in adults with ID. Method: The sample included 52 adults with ID who wore an accelerometer on the hip for 7 days. We determined total sedentary time, percent of wear time spent sedentary, number and duration of sedentary bouts, and breaks in sedentary time. We used t-tests and 2×2 ANOVA to evaluate the effects of sex or age-group and …

Phase Of Enhancement And Plane Of Reconstruction Affect The Appearance Of The Normal Canine Small Intestine When Utilizing Triple-Phase Computed Tomographic Angiography, Jordan Taylor Hatfield

Theses and Dissertations

The use of computed tomography in patients with gastrointestinal disease is increasing. However, the triple-phase computed tomographic angiographic appearance of the canine small intestine and the effects that phase of contrast enhancement and plane of reconstruction have on the appearance of the small intestine have not been fully evaluated. The purposes of this study were to investigate these effects on the appearance of the small intestinal wall. The minimal and maximal small intestinal diameter, wall thickness, number of wall layers identified, and degree of mucosal enhancement were recorded. The plane of reconstruction did not have any significant effects on wall …

Physiological Consequences Of Adverse Early-Life Experiences: A Skeletal Investigation Of Frailty And Resilience Within An Institutionalized Sample Using A Modified Version Of The Skeletal Frailty Index (Sfi), Ashley Dafoe

Theses and Dissertations

This study investigates frailty, defined as the accumulation of deficits in physiological functioning, by applying the Skeletal Frailty Index (SFI) to a skeletal sample (N=67) recovered from the Mississippi State Asylum (MSA), and in a comparative sample, the Terry Collection. The SFI was statistically modified to increase its utility here. Variables that influence frailty, including age, sex, stress in early-life, and resilience, were assessed relative to four SFIs: Overall, Nutritional, Activity, and Infection. This study finds that the predicted relationships between the SFIs and the aforementioned variables are largely absent in the MSA sample. When compared to individuals in the …

Comparing Survival And Growth Among Three Different Planting Stocks Of Water Oak (Quercus Nigra) And White Oak (Quercus Alba) On Lands Damaged By Hurricane Katrina, Austin S. Gentry

Theses and Dissertations

Bareroot, conventional containerized, and large potted EKOgrown® seedlings of water oak (Quercus nigra) and white oak (Q. alba) were planted on two Hurricane Katrina damaged sites in south Mississippi. After two growing seasons, white oak exhibited greater survival (61.1%) than water oak (48.8%) and greater height growth (WHO = 7.4 cm, WAO = 1.4 cm). Water oak had greater groundline diameter (GLD) growth (3.3 mm) and greater second-year height growth (WHO = 2.5 cm, WAO = 9.6 cm). Second-year development could lead to greater height growth by water oak. Bareroot seedlings outperformed other planting stocks in survival and height growth, …

Effect Of Housing Environment And Laying Hen Strain On Performance, Egg Quality And Bone Properties As Well As Cloacal And Eggshell Microbiology, Milan Kumar Sharma

Theses and Dissertations

Laying hen welfare is gaining importance in the United States and several states have passed legislation for a welfareriendly housing environment, which has forced the egg industry to explore alternative housing environments. For this reason, our first objective was to determine the effect of housing environment and laying hen strain on production performance and egg quality. Results showed that production performance of the hens raised in the alternative housing system was similar to the conventional system. The second objective was to compare the eggshell and cloacal microbiology. Our results indicated that the microbial load observed was higher in the alternative …

Biodiversity Of Bariditae (Coleoptera: Curculionidae: Conoderinae) In Mississippi, Ryan Whitehouse

Theses and Dissertations

A survey of Bariditae in Mississippi resulted in records of 75 species in 32 genera and included two undescribed species and 36 new state records. An additional two species were recognized as possibly occurring in Mississippi as well. Diagnoses for all of the genera and species in the state are provided and keys to the genera as well as all of the species were made. Species were found in every county within Mississippi and are representative of the Bariditae fauna of the southeastern United States. Open, prairie-like habitats and aquatic wetland habitats were the habitats with the highest biodiversity of …

Biological, Cultural, And Psychological Factors That May Predispose Young Adults To Anorexia Nervosa, Bulimia Nervosa, And Binge Eating Disorders, Madison Christian

Theses and Dissertations

This study investigated the extent biological, cultural, and psychological factors predispose individuals to eating disorders and compared the prevalence between (N = 103) male and female students (18-27 years of age) from Mississippi State University (MSU). Data was collected from the Eating Disorder Screen for Primary Care (ESP), a media consumption questionnaire, the Contour Drawing Rating Scale (CDRS), the Diet History Questionnaire III (DHQ III), the Eating Attitudes Test-26 (EAT-26), and the Rosenberg Self Esteem Scale. Age of onset was collected if participants identified as having an eating disorder. Data was analyzed using the Mann-Whitey U test and Pearson correlations …

Thermotolerance Classification Of Brassica Carinata Genotypes Using Germination Assay And Vegetative Growth Parameters, Leelawattie Persaud

Theses and Dissertations

Temperature is a major abiotic stress limiting plant growth. Thermotolerance evaluation during germination and early growth may help identify adaptable genotypes of new crops. Two studies were conducted to evaluate temperature effects on 12 Brassica carinata genotypes during germination and early growth. During germination, genotype AX17004 was both the most cold- and heat-tolerant. During early-season growth (35 d after seeding), there were temperature and genotype effects on shoot, root, and physiological components. Cumulative low- and high-temperature response indices, and cumulative root and shoot response indices were related, indicating the importance of these traits. Genotype AX17006 was identified as heat tolerant, …

To Plant Or Not To Plant? A Decision Support Tool To Minimize Risk Associated With Water Level Uncertainty In Reservoir Habitat Management., David M. Norris

Theses and Dissertations

Reservoir mudflats limit development of healthy fish assemblages due to the lack of structural habitat provided by plants. Seeding mudflats with agricultural plants may mimic floodplain wetlands once inundated and provide fish habitat. However, planting success is uncertain because of unpredictable water level fluctuations that affect plant growth. Decision support tools can quantify uncertainty that influences decision outcomes, thus reducing risk in the decision-making process. I used Bayesian Decision Networks and sensitivity analyses to quantify uncertainty surrounding mudflat plantings as supplemental fish habitat in four northwest Mississippi reservoirs. When averaged across all uncertainty, planting was the optimal decision only in …