Life Sciences Commons^™

Investigating Ammonium Toxicity In The Performance Of Recirculating Periphytic Algal Wastewater Treatment Systems, Oluchuku Richie Ochonogor

Theses and Dissertations

Freshwater nutrient enrichment from wastewater facilities and other sources can lead to freshwater eutrophication, a threat to global aquatic ecosystems. Mechanical and chemical ways to curb this threat are either too expensive or not sustainable, and thus, not feasible. Compared to mechanical and other methods, sustainable, inexpensive biological methods (for example, algal treatment systems) have therefore been developed for the removal of excess nutrients from wastewater. By design, secondary waste treatment facilities (WWTF) remove organics and solids and lower oxygen demanding substances; however, they may not remove enough nutrients to protect freshwater ecosystems in all cases. While algae-based biological methods …

Determining The Effects Of Water Quality On Stream Metabolic Function Of Urban Stream Corridors In Columbus, Georgia, Md Abu Raihan

Theses and Dissertations

Urbanization alters streams, disrupting their natural habitat and inducing changes in nutrient dynamics and primary productivity. These human-induced interventions diminish ecological structure, homogenizing once-diverse ecosystems and posing a risk of impairment or destruction. Continuous monitoring of stream ecosystem metabolism emerges as an essential tool for a comprehensive understanding and effective intervention in response to these challenges. This study delves into the intricate dynamics of nutrient levels and productivity within the urbanized context of the Weracoba Creek watershed located in Columbus, Georgia, USA. Through a cross-sectional study, we explore spatial and temporal variations in nutrient concentrations (NH4, NO3, PO4, TP, TN) …

An Analysis Of The Effects Of Temperature And Other Environmental Factors On Microorganismal Productivity Within Aquatic Ecosystems Using Long-Term Data From Various Lter And Ilter Sites, Andrew Dorbu

Theses and Dissertations

Global climate change is a phenomenon resulting in more extreme weather patterns and species diversity loss. In this study, I explore the impacts of climate change on regional patterns of microbial productivity. Variation in microbial productivity was explained using temperature, salinity, and dissolved oxygen as predictors in regression models with data from the LTER and iLTER network of sites that ranged from the poles to the equator. I found a positive relationship between temperature and productivity. Antarctica and Arctic sites exhibited the strongest positive relationships supporting prior research demonstrating temperature as one of the driving forces of productivity change in …

Size Structure And Intraguild Interactions Between Two Ambystoma Species, Gwyneth Daunton

Theses and Dissertations

Intraguild interactions affect population and community structure through a combination of competition and predation. Changes in size structure influence intraguild interactions by affecting the strength and direction of these species’ interactions. I tested for size-structured intraguild interactions in temporary pond ecosystems between marbled salamanders (Ambystoma opacum) and tiger salamanders (Ambystoma tigrinum) using an outdoor mesocosm experiment. I hypothesized that 1) A. opacum survivorship and growth would be negatively impacted when both species start at a similar size because tiger salamanders grow faster and are more aggressive 2) A. tigrinum will grow slower and have lower survivorship when they occur with …

Taxonomic And Phylogenetic Diversity Of Pitcher Plant Bogs In Georgia's Coastal Plain, Melanie Flood

Theses and Dissertations

Diversity studies via floristic survey and taxonomic metrics have proven essential for discerning community composition and biodiversity, however, phylogenetic analyses are necessary to reveal underlying evolutionary change and potential community assembly patterns. Pitcher plant bogs are highly diverse, highly understudied habitats that contain numerous listed and at-risk plant and animal species of Georgia.

In this study I investigated the taxonomic and phylogenetic diversity of pitcher plant bogs by asking the following questions:

1) What is the taxonomic diversity of pitcher plant bogs,

2) What is the dispersion of phylogenetic diversity within bog habitats, and

3) Does taxonomic and phylogenetic diversity …

Effects Of Caffeine Gum On Muscular Strength And Power In Recreationally Active Females, Lindsay D. Montgomery

Theses and Dissertations

Research indicates that a moderate dose of caffeine may enhance muscular strength and power, particularly in males. Less is known on caffeine’s impact on muscular performance in females. The purpose of this study was to determine the effects of a 200 mg dose caffeine gum on muscular strength and muscular power in recreationally active females. Nineteen women participated in 3 laboratory sessions, the first being the familiarization trial. During the next two visits, the participants were given either 200 mg of caffeine gum or a placebo gum, rested for 15 minutes, completed a 10 minute warm-up, then performed performance testing …

A Histopathological Review Of Immune Response In Largemouth Bass To Parasitic Infections Of Soft Tissues, James D. Stephenson

Theses and Dissertations

The immune response can serve as a key indicator of a fish’s overall health and the effect stressors have on the health of the fish. Anthropogenic factors can stress a fish’s immune system and inhibit immune responses. This study investigated the response of eosinophilic cells and macrophage aggregates to parasites in the livers, spleens, and gonads of Largemouth Bass, Micropterus salmoides. Largemouth Bass were sampled from three bodies of water in the Chattahoochee Valley of varying levels of urbanization. Histopathology of the aforementioned organs was conducted to observe both the parasite density and immune response. Eosinophilic cells were shown to …

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 …

Earliest Known Material Of Amia, Bowfin, From The Sentinel Butte Formation (Paleocene), Medora, North Dakota, Abby Grace Moore

Theses and Dissertations

Amia calva is an icon in the field of comparative osteology, yet we have a poor understanding of the evolution of the genus because many fossil amiid bones have gone unidentified. Here we identify new material of the genus, Amia, with evidence of two unidentified species. Previously, the oldest known material identifiable as Amia cf. A. pattersoni, was a specimen from the Paleocene epoch of Alberta, Canada approximately 58 million years in age. Fossils of the two unidentified species of Amia were found in the Sentinel Butte Formation, a geologic formation of Paleocene age (~ 60 million years ago) near …

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. I also …

Estimating Taxonomic Diversity Using Centrum Growth Profiles And Stinger Morphology Of 36 Million Year Old Stingrays From North Dakota, Persia S. Tillman

Theses and Dissertations

Stingrays are a diverse and popular group of vertebrates; however, nothing is known about the relationships between growth biology and climate change. Freshwater stingrays once inhabit the United States and Canada during very warm times in the geologic record. No stingray material has been recorded from the northern part of the United States for the last 33 million years. The Earth’s climate cooled from 50 to 33 million year ago when many warm adapted organisms were relegated to warmer, southern latitudes in North America. Today, freshwater stingrays only inhabit subtropical and tropical environments. We are interested in the freshwater stingrays …

Non-Native Leaf Litter Modifies Algal Resources With Effects On Tadpole Growth, Spencer L. Cruz

Theses and Dissertations

Leaf litter species play a key role in determining the quality and quantity of algal resources in aquatic ecosystems as a cross-boundary subsidy. The invasion of non-native plant species into forests can alter aquatic resources. I investigated the effects of non-native leaf litter species on algal resources and green frog, Lithobates clamitans, development using a randomized complete block experiment that lasted 288 days. In experimental ponds, I added two non-native and two native leaf litter species in the presence and absence of tadpoles. Early in the experiment, Japanese honeysuckle and Chinese privet decreased periphyton N:P ratios and stimulated tadpole growth …

The Relationship Between Biofilm Production And Human Respiratory Cell Attachment And Invasion By Acinetobacter Baumannii, Rachel A. Pearson

Theses and Dissertations

Acinetobacter baumannii is an opportunistic gram-negative bacterial pathogen that causes many nosocomial infections in immunocompromised individuals. Common infections include catheter-associated urinary tract infections, ventilator-associated pneumonia, skin and soft tissue infections, and bloodstream infections that often lead to septicemia. Increasing multidrug resistance (MDR) in A. baumannii warrants new approaches to understanding its virulence mechanisms and pathogenicity. As a first step in infection, A. baumannii can attach to host cells, providing a surface for the bacteria to grow and perhaps facilitating biofilm formation and subsequent tissue invasion. In this study, we evaluated antibiotic resistance and characterized biofilm formation, attachment, invasion, and surface …

An Evaluation Of The Medicinal Plants Of Andros Island, Bahamas, Vivian Pedrozo

Theses and Dissertations

The earliest civilizations have been using plants as their foundation for healing and medicinal traditions for thousands of years. The use of plant medicinals, more commonly known as “bush medicine” on Andros Island, has been rapidly decreasing due an increased presence of western medicine and increased population pressures from urbanization that are threatening local biodiversity hotspots. Ethnobotany is not only important from a conservation standpoint but is also used to preserve traditional knowledge of herbal medicinals and applications, the people of Andros continue to rely on bush medicine, mainly in the form of teas to help manage health related problems. …

A Dietary Analysis On Panamanian Bat Species, John C. Waller

Theses and Dissertations

Bats are found all over the world, and they are the most diverse group of mammals in the tropics. They are a key component in all ecosystems as predators, pollinators, or seed dispersers. As a conservation tool, dietary studies show what different bat species need to survive. Through metabarcoding, the diet can be accurately assessed. This method involves the DNA extraction of material from the feces of the individual being studied. PCR is used to amplify the DNA and next generation sequencing is used to identify, separate, and align the DNA that was extracted. By comparing the results from different …

The Effects Of Ethynodiol Diacetate On Epinephrine-Treated Glial-Derived Cells, Jesse D. Hunt

Theses and Dissertations

Neuroprotective agents, including specific hormones, may play a role in preventing cellular damage following an ischemic event or brain injury. Astrocytes are specialized glial cells within the central nervous system that play roles in synapse development, blood flow regulation, extracellular homeostasis, synapse function, energy and metabolism (Sofroniew and Vinters, 2009). Research using astrocytes in cell viability studies can be beneficial in deepening our understanding of specific neuroprotective effects of various steroid hormones including progesterone. Progesterone has been shown to have neuroprotective capabilities in the central nervous system (Scarpin et ah, 2009). Although progesterone shows great therapeutic potential, effects of the …

The Involvement Of Progesterone In Glial Cell Viability, Tracee L. Guthrie

Theses and Dissertations

We studied the effects of ethynodiol diacetate on the viability of hydrogen peroxide stressed glial cells. We wanted to determine the extent in which varying concentration of ethynodiol diacetate affect cell viability of cultured glial cells from hydrogen peroxide toxicity. Based on previous studies, we predicted that the viability of hydrogen peroxide-stressed cells will increase with the presence of the progesterone, ethynodiol diacetate, and that cell viability will increase with increasing concentration of ethynodiol diacetate. Glial cells of 1x10° cells/well were introduced into a 96-well plate and allowed to grow for 24 hours in an incubator at 37°C and 5% …

Evaluating Columbus, Georgia, Tree Canopy Interactions With Air Pollutants Using High Spectral Imagery And Portable Pm Sensors, Kristin N. Youngquist

Theses and Dissertations

Trees provide environmental, economic, and social advantages in urban areas. Knowing the extent and location of tree canopy in a municipality is an important step in quantifying these benefits. Spatial and temporal tree canopy analysis was performed for the city of Columbus, Georgia, by categorizing the National Agriculture Imagery Program (NAIP) aerial imagery for 2005, 2010 and 2015 into tree versus non-tree land cover type using unsupervised classification procedures. Air pollution removal rates from the i-Tree program were applied to this evaluation providing an estimate of the city’s tree air quality benefits. The city’s canopy overall has remained steady at …

Effects Of Diabetes On Ovarian Cancer: Data Analysis And Modeling Study, Claire Belay

Theses and Dissertations

Ovarian cancer has one of the highest mortality rates of all gynecological cancers [13]. Further knowledge of risk factors for the growth of ovarian tumors would be beneficial in both the treatment and prevention of this type of cancer. Previous research has shown a positive correlation between diabetes and prostate tumor growth [22], The first aim of this study was to determine the effect of diabetes of ovarian tumor growth. The second aim was to develop a model to predict ovarian tumor growth based on the microenvironment within a patient’s body. The hypothesis was that there would be a positive …

A Bronchiolitis Study: The Overuse Of Bronchiolitis Therapies In Children Admitted Into The Hospital, Jocelyn S. Canedo

Theses and Dissertations

Bronchiolitis is prevalent among infants of 0 to 12 months, and usually caused by a variation of viruses. Signs and symptoms consist of coughing, rapid breathing, and an occasional fever in some infants. Bronchiolitis is not treated with antibiotics, but rather with proper medical examination and other procedures. Chest radiographs, steroids, and certain bronchodilators are considered ineffective treatments. This study identified the amount of ineffective procedures being used in infants admitted into the pediatric emergency room, and the effect it had on the patient’s average hospital stay. Past medical records were used in this clinical study. Statistical analyses and graphs …

Using Maximum Entropy To Model The Distribution Of An Endangered, Endemic Crayfish Cambarus Harti (Hobbs), James Kiourtsis

Theses and Dissertations

Cambarus harti is a state-listed endangered, endemic crayfish found only in three counties in mid-west Georgia. Several studies have attempted to characterize the biology and ecology of this crayfish, however data regarding the distribution of this rare, endemic crayfish remains limited. The International Union for Conservation of nature stated that in order to create an effective conservation plan, the known distribution must be expanded. Species distribution models are a cost-effective way to identify locations that have similar habitat characteristics to those with known populations. One species distribution model, Maximum Entropy (MaxEnt), is the preferred approach when modeling species, like C. …

Improving Estuarine Water Quality In South Florida: A Quantitative Evaluation Of The Efficacy Of A Local Nutrient Ordinance, Kerstin Motsch

Theses and Dissertations

Degraded coastal water quality is a concern in Florida, in part due to nutrient enrichment of aquatic ecosystems causing eutrophication and excessive algal growth. In 2010, a fertilizer ordinance was enacted in Cape Coral located in Lee County Florida with the objective of reducing nutrient loads from local fertilizing practices in order to improve water quality within the city. In order to assess its efficacy, a before after control impact (BACI) design was implemented using Fort Lauderdale in Broward County Florida as a reference location. A total of twenty estuarine canal sampling locations were identified in both Lee and Broward …

Effects Of Grazers And Elevated Temperature On The Dynamics Of A Wastewater Algal Treatment System, Mengyuan Li

Theses and Dissertations

Wastewater algal treatment systems (ATS) have been shown to effectively remove excessive nutrients from wastewater and prevent eutrophication. However, the performance of ATS could be strongly affected by environmental factors. This study examined (1) the effect of grazers on nutrient removal rates and (2) the effect of 1.7 °C increase in temperature on algal biomass. The effect of grazers was assessed outdoors by analyzing dissolved and tissue nutrient concentrations in ATS with and without biological pesticide in two 20-day trials. The effect of elevated temperature was evaluated indoors by comparing algal biomass between heated and non-heated ATS for 20 days. …

Effects Of Estrogens On Astrocytes Exposed To Stressors, Bridget N. Smith

Theses and Dissertations

Hormone replacement therapy (HRT), used by many women to alleviate menopausal symptoms such as hot flashes and mood swings, is often a combination ofhormones such as estrogens, progesterone, and conjugated equine estrogens (CEE), extracted from the urine of pregnant mares. Previous studies have found positive correlations between estradiol and cellular protection, but recent research has concluded CEE provide less protective mechanisms as compared to endogenous hormones. This research sought to compare the effects of estrogen treatments (single and combined estrogen) on viability when astrocytes were induced with stressors (epinephrine, cortisol, and low oxygen concentration). Cultured human astrocytes were treated with …

Estrogen's Effects On Oxidative Stress Levels In Glial Cells, Jacob J. Dirkman

Theses and Dissertations

A decrease in astrocyte function and viability has been linked to many neurodegenerative diseases, including schizophrenia, major depressive disorders, Alzheimer’s disease, and Amyotrophic Lateral Sclerosis (ALS). Previous research indicates that some estrogens may have a positive effect on neuron and astrocyte viability. Estrogens’ effects on the brain are of interest as estrogens are commonly prescribed as hormone replacement therapy to reduce the symptoms of menopause in women. Unfortunately, these effects on are not completely understood. The goal of the project was to discover if estrogen has any protective effect on astrocytes exposed to oxidative stress. We measured the oxidative stress …

Phylogenetic Analyses Of Andean And Amazonian Tree Communities In Ecuador, Samantha J. Worthy

Theses and Dissertations

The forests of Ecuador are known for their high levels of diversity and endemism, classifying the country as a biodiversity hotspot. Both the western Amazon and Andean montane forests are richly populated with tropical tree species that have been little studied in a community phylogenetic context. The implementation of elevational transects and trait based analyses having proven useful in gaining a better understanding ofhow environmental factors are affecting the tree community structure in these habitats. The goal of this research was to evaluate the magnitude ofDNA barcode diversity among Amazonian and Andean tree species. Specifically, the objectives were to (1) …

Impact Of A Diesel Spill On Macroinvertebrate Communities In Ponds In S.E. Alabama, Usa, Katie E. Winkles

Theses and Dissertations

No abstract provided.

The Loss Of Methanol Utilization In Methylobacteria, Justin T. Skariah

Theses and Dissertations

Methylobacteria primary uses Cl substrates as a carbon and energy source. This experiment was performed to see if Methylobacteria would lose the ability to use Cl compound methanol after prolonged exposure to multi-carbon substrates. To determine this, the bacteria was grown on MR2A3 (multi-carbon substrates) and MOM (single-carbon substrates) for multiple generations and tested for loss of function on a series of generations. These tests include streaking plates of MOM and R2A with bacteria from MR2A3 then getting a bacterial colony count and also toothpick transfers of the colonies to verify findings. After 20 generations there were no significant decrease …

The Involvement Of Estrogen Receptors In Astrocyte Survival, Lauren M. Johnson

Theses and Dissertations

Estrogens are a class of hormones that are demonstrated to be neuroprotective. The levels of estrogen in the body decline during menopause which can cause a variety of symptoms. Hormone replacement therapy (HRT) is a treatment option for menopause, however, it has been demonstrated to have adverse side effects. Of the treatment options for adverse side effects of HRT, Selective estrogen Down-regulators do not appear to have an agonist effects on estrogen receptors while Selective estrogen receptor Modulators do. The aim of this study was to determine the role that estrogen receptors play in the survival of astrocytes when placed …

Screening For Pathogenic Escherichia Coli In The Chattahoochee River, Columbus, Georgia, Micah A. Staples

Theses and Dissertations

Escherichia coli testing is frequently used to indicate the possible presence of harmful pathogens, but E. coli itself can be pathogenic. Serotype 0157:H7, enterohemorrhagic E. coli, is likely the most medically important pathogenic strain of E. coli in the United States. In this study, we surveyed for 0157:H7 and three strains of another pathogenic subtype: enterotoxigenic E. coli. We isolated E. coli colonies from samples taken from the Chattahoochee River in Columbus, Georgia at two different locations, above and below wastewater outputs. We used PCR to test for the individual subtypes and then used a nested PCR protocol for the …