Life Sciences Commons^™

Soybean Iron Deficiency Chlorosis: Quantitative Trait Locus Validation And Grain Yield Evaluation, Ahmed Charif

Electronic Theses and Dissertations

Soybean production in most of the Northern Great Plain area has been challenged by iron deficiency chlorosis (IDC), which is a physiological problem with a plant grown in high pH, calcareous soil. Developing IDC-resistant cultivars is the best approach to meet this challenge. Currently, this approach is limited by lack of knowledge about genetic resources and mechanisms for resistance to IDC. The objectives of this research were to validate quantitative trait loci (QTL) associated with IDC and to evaluate the effect of IDC on yield in soybean cultivars. To validate the QTL, a population of 201 recombinant inbred lines, which …

Efficacy Of Seed Treatments, Microbial And Biochemical Pesticides For Managing Early Tan Spot And Stripe Rust Diseases Of Wheat, Collins Bugingo

Electronic Theses and Dissertations

Wheat is a major cereal crop in the U.S.A and in the world. However, its production is hampered by a number of factors both biotic and abiotic. Foliar diseases like tan spot caused by Pyrenophora tritici-repentis and stripe rust caused by Puccinia striiformis f. sp. tritici, are economically important diseases causing over 5-55 % yield loss. To assess the efficacy of fungicide seed treatments in the management of early tan spot, two hard red spring wheat cultivars “Select” and “Brick” were treated with seedapplied commercially available combo fungicides metalaxyl + pyraclostrobin + triticonazole and difenoconazole + mefenoxam + sedaxane …

The Contributions Of Fc Gamma Receptors And Macropinocytosis To The Internalization, Sorting And Clearance Of Antibody Coated Nanovesicles In Macrophages, George Opoku-Kusi Jr.

Electronic Theses and Dissertations

Macrophages are tissue-resident phagocytes that play critical roles in immune response and tissue homeostasis. They have a tremendous capacity to internalize objects of various sizes ranging from nanoscale viral particles to micron sized bacteria and tumor cells. This phenomenon, termed phagocytosis for the uptake of large particles, or endocytosis for the uptake of small particles, is integral to the immune response in multicellular organisms. Macrophages express FcγRs, which are tyrosine kinase receptors that bind IgG on an opsonized target. Binding of IgG Fc domain to the extracellular domain of an FcγR triggers signaling cascades that coordinate internalization of the opsonized …

The Effects Of Acidic Conditions And Tannins On The Survival, Development, And Behavior Of Cope’S Gray Treefrog (Hyla Chrysoscelis), Caleb E. Dodd

Electronic Theses and Dissertations

As amphibians decline around the world, freshwater acidification resulting from pollutants and acid rain may be a contributor. The ability of organisms to cope with environmental changes is greatly mediated by behavior, and recent studies indicate that anthropogenic acidification impairs behavioral responses by impacting olfactory abilities of aquatic organisms. Responding appropriately to novel stimuli is important for individual performance and survival, and pollutants may cause organisms to behave maladaptively. In this study I sought to: a) determine whether the oviposition site choices of adult female frogs correspond with the pH and tannin conditions that maximize tadpole survival and performance in …

Mcdonald’S Users’ Perceptions Of Health And Nutrition, Quality, And Value On Visit Frequency, Claire Adams

Electronic Theses and Dissertations

With the vast amount of quick service restaurants (QSRs) that are available to consumers in the United States (U.S.), the hospitality industry has become an integral part of Americans’ diet and lifestyle. This study examines how McDonald’s customers’ perceptions of health and nutrition, quality, and value vary demographically (gender, age, ethnicity, educational level, and body mass index [BMI]) by McDonald’s visit frequency. An online survey was employed to collect data of participants who were 18 years of age and older, McDonald’s customers, and a resident of the U.S. Of the 843 respondents who filled out the survey, 607 (72%) surveys …

The Effect Of Restaurant Menu Labeling On Attitudes Towards Menu Labeling And Eating Behaviors Of Ncaa Athletes, Recreational Athletes, And Non-Athletes’ In A University Setting, Virginia Mitchell

Electronic Theses and Dissertations

Intro College students eat the majority of their meals outside of the home, which likely means that college students are impacted by calories consumed in restaurants, including campus dining halls. The Affordable Care Act, while not fully operationalized, requires calorie content labels be included on menus and menu boards in restaurants so that consumers are aware of the calories of menu items selected. Therefore, it is important to explore college students, including athletes, attitudes and behaviors toward menu labeling in an on-campus dining facility setting. The objectives of this study were to determine NCAA athletes, recreational athletes, and non-athlete’s attitudes …

Comparisons Of Time To Task Failure And Muscle Activity For Two Different Submaximal Fatiguing Contractions, Sunggun Jeon

Electronic Theses and Dissertations

The aim of this study was to examine the time to task failure for two different fatiguing tasks (force vs. Position task) on elbow flexion exercise, in order to explore potential mechanisms of muscle fatigue. Twenty healthy and recreationally active individuals (10 men and 10 women) participated in this 3-visit investigation. At least 48 hours after the first visit as the familiarization, the subject returned for one of the experimental visits (order randomized). During the force task visit, the subject performed maximal voluntary contractions (mvcs), several submaximal trapezoid isometric contractions with different intensities (40% and 70% of mvc), and folloby …

Comparison Of Air Displacement Plethysmography And Dual-Energy X-Ray Absorptiometry For Estimation Of Body Fat Percentage In National Collegiate Athletic Association Division I Athletes, Caitlyn Rose Chenevert

Electronic Theses and Dissertations

The aim of this research is to study the Apple iOS and Android mobile frameworks from a developers' perspective. The first chapter introduces a historical overview of operating systems for mobile devices as well the motivation and objectives of the research. The second chapter introduces basic principles of the iOS and Android mobile frameworks in order to evaluate the platforms. The third chapter evaluates and compares the main features of both frameworks. The fourth chapter discusses the implementation of several applications on the iOS and Android mobile frameworks, which are used to demonstrate the advantages and disadvantages of each platform. …

Impacts And Implications Of Polytypism On The Evolution Of Aposematic Coloration, Justin Philip Lawrence

Electronic Theses and Dissertations

Aposematic signaling is a comdefensive strategy whereby prey species use conspicuous signals (i.e., bright coloration) to warn predators of the risks of predation due to a secondary defense. Theoretical, lab, and field experiments have demonstrated that individuals who project novel conspicuous signals should experience disproportionately high predation pressure as predators will not associate novel signals with a secondary defense. Thus, aposematic signaling should be subject to strong positive frequency-dependent selection (FDS). Numerous species show considerable intrapopulation variation (polymorphism) in direct conflict with the expectations of FDS. Interpopulation variation (polytypism) can adhere to expectations of FDS, but as its origins likely …

Effects Of Hydrological Connectivity On The Benthos Of A Large River (Lower Mississippi River, Usa), Audrey B. Harrison

Electronic Theses and Dissertations

The effects of hydrological connectivity between the Mississippi River main channel and adjacent secondary channel and floodplain habitats on macroinvertebrate community structure, water chemistry, and sediment makeup and chemistry are analyzed. In river-floodplain systems, connectivity between the main channel and the surrounding floodplain is critical in maintaining ecosystem processes. Floodplains comprise a variety of aquatic habitat types, including frequently connected secondary channels and oxbows, as well as rarely connected backwater lakes and pools. Herein, the effects of connectivity on riverine and floodplain biota, as well as the impacts of connectivity on the physiochemical makeup of both the water and sediments …

A Comparison Of The Acute Muscular Response And Long-Term Adaptation To Resistance Training Using Traditional High Loads Or Very Low Loads With Different Degrees Of Blood Flow Restriction In The Lower Body, Matthew Brian Jessee

Electronic Theses and Dissertations

Purpose: To compare acute and chronic responses to lower body resistance exercise using: high-load (70/0), very low-load alone (15/0), with moderate (15/40), or higher (15/80) blood flow restriction. Conditions labeled (% One-repetition maximum/% arterial occlusion pressure). Acute: Trained participants (12 males, 11 females) completed knee extension exercise (4 sets to failure capped at 90 repetitions) with each condition. Muscle thickness and torque were assessed before (Pre), after (Post), and fifteen minutes after (Post-15) exercise; surface electromyography (EMG) during. Chronic: Untrained participants (20 males, 20 females) performed the same exercise, with one condition assigned to each leg, twice per week for …

Acute And Chronic Skeletal Muscle Response To Very Low Load Resistance Exercise With And Without The Application Of Blood Flow Restriction In The Upper Body, Samuel Louis Buckner

Electronic Theses and Dissertations

This study examined the acute and chronic effects of resistance exercise with and without blood flow restriction (BFR) on skeletal muscle. Methods: The acute study examined changes in torque, muscle thickness (MTH), and surface electromyography (EMG) in response to resistance exercise with high load [70% 1RM,(7000)], low load [15% 1RM,(1500)], low load with moderate (BRF) [15% 1RM+40%BFR(1540)], or low load with greater BFR [15% 1RM+80%BFR(1580)]. The chronic study investigated changes in MTH, strength, and endurance following 8-weeks. Acute results: Following exercise, the 7000 condition had lower (p<0.05) MTH [4.2(1.0) cm] compared to the 1500 [4.4 (1.1)cm], 1540 [4.4(1.1)cm], and 1580 [4.5(1.0cm] conditions. This continued 15 minutes post. Immediately following exercise torque was (p<0.05) lower in the 1500 [31.8 (20) Nm], 1540 [28.3(16.9) Nm] and 1580 [29.5 (17) Nm] conditions compared to the 7000 condition [40 (19) Nm]. 15 minutes post, 1500 and 1540 conditions demonstrated lower torque compared to the 7000 condition. For the first three repetitions of EMG the 7000 condition displayed greater amplitude compared to all low load conditions (p<0.001). For the last three repetitions percentage EMG was greater in the 7000 compared to the 1580 condition. Chronic results: 1RM strength changes were greater in the 7000 condition [2.09 (95% CI=1.35-2.83) kg] compared to all low load conditions. For isometric and isokinetic strength there were no changes. For endurance there was a main effect for time [mean pre to post change = 7.9 (4.3–11.6) repetitions]. At the 50% site, the mean change in MTH in the 7000 condition [0.16 (0.10-0.22) cm] was greater than all low load conditions. For the 60% site, the mean change in MTH [0.15 (0.08-0.22)] was greater than all low load conditions. For the 70% site there was a main effect for time [mean pre to post change = 0.09 (0.5–0.14 cm]. Conclusions: Very load loads produce a similar acute response regardless of pressure. This response was greater than that observed in the 7000 group. Very low loads produce skeletal muscle growth. However, this response is not as robust as that observed following high load training.

Predictive Modeling Of Hip Dislocation: Assessment Of Surgical And Patient Factors To Reduce The Occurrence Of Hip Instability And Adverse Clinical Outcomes, Daniel N. Huff

Electronic Theses and Dissertations

Instability and dislocation remain leading indications for revision of primary Total Hip Arthroplasty (THA). Many studies have addressed the links between implant design and propensity for dislocation, however a comprehensive review of the ability of modern THA constructs to protect against joint instability is needed.

Accordingly, the objective of this study is to provide objective data about THA risks to be considered in the treatment algorithm to protect against adverse joint loading conditions and joint instability. Adverse loading conditions were assessed in a population of activities of daily living using data from telemetric hip implant representation in an FE simulation …

Environmental And Physiological Regulation Of Yellow Stingray Color Change, Theresa Rose Gunn

Electronic Theses and Dissertations

Many reef fishes exhibit dynamic coloration and body patterns that can change under nervous or hormonal control. Several species of benthic sharks and rays likely alter melanin in the skin to provide background matching for camouflage. The yellow stingray (Urobatis jamaicensis) is a benthically-oriented elasmobranch with elaborate spot patterns that provide effective camouflage within its habitats. This patterning, when coupled with the ability to alter melanin in response to background color, could increase background matching effectiveness in these species. The yellow stingray has been anecdotally noted to lighten or darken skin color.However, it is unclear whether this type …

Characterizing The Complex Relationship Between The Brown Widow Spider And Its Bacterial Endosymbiont, Wolbachia, Emily Knight

Electronic Theses and Dissertations

The brown widow spider, Latrodectus geometricus (C. L. Koch 1841), has been found to harbor the maternally inherited bacterial endosymbiont Wolbachia pipientis (Hertig and Wolbach 1924), but endosymbiont infection frequency varies widely among Southeastern US populations. Wolbachia is known to manipulate the reproduction of its hosts through male feminization, parthenogenesis, male killing, and cytoplasmic incompatibility. In brown widows, Wolbachia does not alter sex ratios, but any other effects the symbiont has on the spider are unknown. In my first chapter, I assess if there is linkage between Wolbachia infection and maternally inherited mitochondrial DNA (mtDNA) in three brown widow populations. …

Foraging Ecology Of A Winter Bird Community In Southeastern Georgia, Rachel E. Mowbray

Electronic Theses and Dissertations

Classical views on community structure emphasized deterministic processes and the importance of competition in shaping communities. However, the processes responsible for shaping avian communities remain controversial. Attempts to understand distributions and abundances of species are complicated by the fact that birds are highly mobile. Many species migrate biannually between summer breeding grounds and wintering grounds. The goal of this study was to test four hypotheses that attempt to explain how migratory species integrate into resident assemblages of birds (Empty-Niche Hypothesis, Competitive-Exclusion Hypothesis, Niche-Partitioning Hypothesis, and Generalist-Migrant Hypothesis). I collected data on birds foraging during the winter of 2017-2018 in Magnolia …

Quantifying Genetic Responses Of Plants To Drought Stress With A Comparative Transcriptome Approach, Jessica K. Devitt

Electronic Theses and Dissertations

Mentzelia section Bartonia (Loasaceae) commonly occurs in some of the hottest and driest places in North America, but we poorly understand the mechanisms that allow them to tolerate such extreme environments. Morphological and physiological adaptations are well studied in model organisms. The underlying genetic responses to drought stress in non-model organisms like Mentzelia is unknown. To better understand and identify differences and similarities in genetic responses to drought stress between species existing in different habitats with differing water availability, three species from the genus Mentzelia were compared. Species of section Bartonia occur across an environmental gradient, from temperate to arid …

An Investigation Into The Physiological Impacts Of Ocean Acidification On Recruits Of The Temperate Coral, Oculina Arbuscula, Brianne Varnerin

Electronic Theses and Dissertations

Ocean acidification is well-researched with respect to adult scleractinian corals, however information on whether adults and recruits of the same species respond similarly to this environmental stress is lacking. I investigated the responses to increased pCO₂ of recruits of the temperate coral, Oculina arbuscula, whose adults are known to withstand high levels of pCO₂ with no depression in calcification (up to 1000 ppm CO₂). I addressed the hypothesis that O. arbuscula recruit health is not affected by increased pCO₂ by exposing small colonies (5-12mm diameter) to 475, 711, and 1270 ppm CO₂ for …

How Anxiety In Adolescent Athletes May Affect Baseline Neuropsychological Test Scores, Christopher P. Tomczyk

Electronic Theses and Dissertations

Background: Anxiety is highly prevalent in the adolescent population and can affect performance on cognitive tasks. As part of a concussion protocol, measuring cognitive ability through the use of baseline neuropsychological testing is recommended in the high school setting. Because of the cognitive nature of baseline testing, there is potential for anxiety to influence scores. Purpose: To examine the effects of varying levels of state and trait anxiety on a baseline computerized neurocognitive assessment in the adolescent population. Methods: 75 adolescent athletes (age:15.91±1.33, height (cm): 168.72±9.07, weight (kg): 62.97±12.04) participated in the study. Cognitive ability was measured …

Morphological And Behavioral Traits Associated With Locomotion In Lizards, Chase T. Kinsey

Electronic Theses and Dissertations

Morphology, locomotion, and behavior are co-adapted to optimize performance and ultimately fitness. Successfully navigating a complex environment is dictated by an animal’s locomotor behavior, and for some behaviors, its locomotor performance. The locomotor performance of an organism is directly related to the form and function of the structures involved in locomotion such that movement is efficient – that is, minimal loss of energy. The first chapter of this thesis focuses on the effects of obstacle placement and forelimb position on facultative bipedalism. Placing an obstacle beyond a lizard’s acceleration threshold did not affect the frequency of bipedal posture. Furthermore, the …

Movement In Cats, Valerie N. Plummer

Electronic Theses and Dissertations

Feral cats (Felis catus) are listed as one of the '100 world's worst invasive alien species'. There are as many as 70-100 million feral cats in the United States as well as an estimated 117-157 million domestic indoor and outdoor cats. Management efforts include a nonlethal feeding and sterilization program known as "trap-neuter-release" (TNR) where cats are surgically sterilized and returned to the environment. Population size and structure, immigration rates, spay/neuter rates, and data on spatial use all play a role in whether TNR is a viable management option. This study focuses on population structure and spatial use. …

The Mediation Of Perfectionism And Rumination On Mindfulness And Burnout In Collegiate Athletes, Nicholas S. Mcmillen

Electronic Theses and Dissertations

Several positive and negative sport-related experiences can occur throughout an athlete’s career, which can affect the continuation or termination of said career. Although research has associated sport participation with positive outcomes (e.g., increases in motivation, autonomy), there are also negative sport-related outcomes such as burnout (Akhrem & Gazdowska, 2016; Garcia, 2015). Specifically, burnout has been identified as a multidimensional construct that includes three dimensions. Furthermore, mindfulness has been studied to minimize the risk of experiencing burnout (Kabat-Zinn, 2003). While several studies have examined mediators between mindfulness and burnout, there has been a dearth of research on perfectionism and rumination as …

The Role Of Relatedness In Youth Athlete Burnout, Megan Wittenberg

Electronic Theses and Dissertations

The Aspen Institute’s 2016 State of Play report projects a decline in youth sport participation that is more pronounced in adolescent athletes. Although there are numerous potential benefits for youth sport participation, there are also potential consequences including burnout (chronic psychological syndrome consisting of emotional and physical exhaustion, reduced sense of accomplishments, and sport devaluation (Raedeke, 1997). Approximately 1% to 9% of adolescent athletes experienced elevated levels of burnout, with current research suggesting that relatedness could have an influence on athlete burnout. In this instance, relatedness was defined as the extent to which individuals perceives significant others are genuinely invested …

Evaluating Elasmobranch Bycatch And Shark Depredation In The Georgia Shrimp Fishery, Matthew M. Scanlon

Electronic Theses and Dissertations

The Georgia shrimp fishery has seen a dramatic decrease in profit and productivity since the 1980’s due to a number of economic factors. Additional, yet undocumented, pressures on this fishery include interactions between foraging sharks with trawl gear. Fishermen report that sharks frequently bite nets in an attempt to prey on netted fish, resulting in large holes in the gear. Further elasmobranch interactions with trawl gear occur as bycatch; shrimp trawls represent nearly 100% of elasmobranch commercial bycatch in Georgia state waters, the species composition of which is largely unstudied. Shark interactions with nets were detailed through fishery-dependent observations on …

Comparison Of Three Benthic Macroinvertebrate Passive Sampling Devices For Non-Wadeable Streams, Kelsey A. Laymon

Electronic Theses and Dissertations

Rivers and streams provide essential ecosystem services to the degree that the monitoring and maintenance of these systems becomes imperative. Biomonitoring provides managers and policymakers with the tools to make informed decisions, and macroinvertebrates are often the object of biomonitoring because they are ubiquitous in most systems and are known to be good indicators of water quality. However, methods for sampling macroinvertebrates in non-wadeable streams (i.e., large rivers) have not been standardized across states and regions and an established method for macroinvertebrate biomonitoring in large rivers of Georgia is not currently available. My study compared macroinvertebrates collected with three types …

Examining The Issue Of Compliance With Personal Protective Equipment Among Wastewater Workers Across The Southeast Region Of The United States, Tamara L. Wright

Electronic Theses and Dissertations

Wastewater workers are exposed to different occupational hazards such as chemicals, gases, viruses, and bacteria. Personal Protective Equipment (PPE) is a significant factor that can reduce or increase the probability of an accident from hazardous exposures to chemicals and microbial contaminants. The purpose of this study was to identify wastewater worker’s beliefs and practices on wearing PPE and protections offered by PPE through the integration of the Health Belief Model (HBM). Participants were workers in the wastewater industry, which included wastewater operators, laboratory analysts, maintenance workers, wastewater collection workers, equipment operators, managers, and supervisors (n=272). The instrument was a self-administered …

Tissue Specificity Of Sex-Biased Gene Expression And The Development Of Sexual Dimorphism, Albert K. Chung

Electronic Theses and Dissertations

One prominent form of phenotypic diversity in nature is the dramatic difference between males and females within a single species. A central genetic obstacle which must be overcome is that two distinct phenotypes must be produced from a single, shared genome. One genetic mechanism that is of particular import that would allow sexes to overcome the limitation of a shared genome is sex-specific regulation of gene expression. Although sex-biased gene expression is generally predicted to increase over ontogeny as male and female phenotypes diverge, this pattern should be most pronounced in tissues that contribute to the most extreme aspects of …

Environmental Factors Affecting Hatch Success In The Loggerhead Sea Turtle (Caretta Caretta), Mattie J. Whitesell

Electronic Theses and Dissertations

The loggerhead turtle (Caretta caretta) is a species federally listed as “threatened” whose global populations are declining. Georgia Department of Natural Resources conservation protocols for this species require the daily monitoring of nesting activity and permit physical relocation of nests which are at risk of being eroded or flooded by storms and high tides in order to increase hatch success--the proportion of hatched to unhatched eggs. Relocated nests are moved to an area with higher elevation in order to avoid flooding, but other variables such as increased temperature and decreased moisture are introduced when relocating. For years temperature …

Saccadic Eye Movements Between Strategic, Interceptive, And Non-Athletes, Brian Szekely

Electronic Theses and Dissertations

Introduction: Athletes have differences in object tracking, search strategies, number and duration of fixations, dynamic visual acuity (DVA), and predictive eye movements than non-athletes (NON). However, these eye functions have not been assessed between athlete groups during a task that encompasses antisaccade and DVA characteristics. Purpose: To evaluate the oculomotor control sport paradigm differences between interceptive (INT) and strategic (STR) Division I collegiate athletes, as well as NON with an antisaccade task (AS) and a sport-like dual task (SDT). Methods: Fifty-seven participants (19 STR, 19 INT, and 19 NON) performed 2 trials of an AS and a SDT. Participants stood …

Predictors Of Fish Assemblage Structure And Dynamics In Atlantic Coastal Plain Streams, Rebecca Scott

Electronic Theses and Dissertations

Effective management of freshwater fishes requires a mechanistic understanding of the drivers of assemblage composition; in other words, what determines who is where and when. Stream fish assemblages are potentially influenced by environmental factors that act on multiple spatiotemporal scales, but the relative influence of these drivers may vary between geophysically distinct regions. This study sought to determine the patterns and drivers of fish taxonomic and functional assemblage composition in the coastal plain, a region possessing unique hydrologies, faunas, and physiochemical conditions. I addressed this goal using two complementary chapters, both of which utilized environmental and biotic data collected from …