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Third Ventricle Width As A Metric For Fast And Efficient Detection Of Atrophy In Traumatic Brain Injury, Christopher Scott Finuf Dec 2015

Third Ventricle Width As A Metric For Fast And Efficient Detection Of Atrophy In Traumatic Brain Injury, Christopher Scott Finuf

Theses and Dissertations

In an average year more than 1.7 million people will experience a traumatic brain injury (TBI) in the United States. It is known that atrophy occurs across a spectrum for TBI patients, ranging from mild to severe. Current conventional magnetic resonance imaging (MRI) methods are inconsistent in detecting this atrophy on the milder end of the spectrum. Also more contemporary imaging tools, although efficient, are too time consuming for clinical applicability. It is for these reasons that a quick and efficient measurement for detecting this atrophy is needed by clinicians. The measuring of third ventricle width had the potential to …


Evidence Of Ancient Maya Agriculture In The Bajos Surrounding Tikal, Guatemala, Adam Calvin Parker Dec 2015

Evidence Of Ancient Maya Agriculture In The Bajos Surrounding Tikal, Guatemala, Adam Calvin Parker

Theses and Dissertations

Current Central American agricultural practices are environmentally and economically unsustainable, yet the ancient Maya who lived in the same region thrived for thousands of years. Archaeologists have attempted to understand the factors enabling the prolonged success and ultimate collapse of the Maya societies. Some have proposed that the karst seasonal wetlands, called bajos, that border many Maya sites in the region were an influential factor in the Maya's ability to flourish. For the past decade, researchers have used carbon isotope analyses to identify areas of ancient maize agriculture at Maya archaeological sites. In this study, we collected soil samples from …


Folate Stability In Fortified Corn Masa Flour, Tortillas, And Tortilla Chips, Renee Phillips Dec 2015

Folate Stability In Fortified Corn Masa Flour, Tortillas, And Tortilla Chips, Renee Phillips

Theses and Dissertations

Neural tube defects (NTDs) occur at higher rates in Hispanic populations in the USA. Such populations would benefit from folic acid fortification of corn masa flour (CMF). This study evaluated folate stability in fortified CMFs and products made from the flours, tortillas and tortilla chips. There was no significant loss of folate during the six-month shelf-life of fortified tortilla CMF and tortilla chip CMF. There was a 13% loss (P < 0.05) of folate during tortilla baking and no loss during tortilla chip frying. Both tortillas and tortilla chips showed significant folate losses over the two-month shelf-life for these products, with a 17% loss in fortified tortillas and 9% loss in tortilla chips. Folate in fortified CMFs, tortillas and tortilla chips is relatively stable and comparable to the stability of folate in wheat flour and breads.


Blockade Of Tgf-Ss Signaling Through The Activin Type Iib Receptor With The Small Molecule, Sgi-1252, Jordan David Fuqua Dec 2015

Blockade Of Tgf-Ss Signaling Through The Activin Type Iib Receptor With The Small Molecule, Sgi-1252, Jordan David Fuqua

Theses and Dissertations

Antagonism of the activin receptor signaling pathway represents a promising potential therapy for the muscular dystrophies and other muscle wasting disorders (i.e., cachexia or sarcopenia). Previous research has shown that antagonism of activin signaling promotes muscle growth, attenuates muscle wasting, and restores function in both wild type and diseased animals. Our laboratory has recently developed a novel small molecule (SGI-1252) that inhibits activin downstream (i.e., Smad2/3 phosphorylation) signaling. Purpose: In this study we determined how eight weeks of orally administered SGI-1252 affected TGF-ß signaling, whole body mass, individual limb muscle mass, and muscle fiber cross sectional area (CSA). Methods: Wild-type …


Calcium Signaling And Ca2+/Calmodulin-Dependent Kinase Ii Activity In Epithelial To Mesenchymal Transition, Melissa Ann Mcneil Dec 2015

Calcium Signaling And Ca2+/Calmodulin-Dependent Kinase Ii Activity In Epithelial To Mesenchymal Transition, Melissa Ann Mcneil

Theses and Dissertations

Epithelial to mesenchymal transition (EMT) is an important process in embryonic development, tissue repair, inflammation, and cancer. During EMT, epithelial cells disassemble cell-cell adhesions, lose apicobasal polarity, and initiate migratory and invasive processes that allow individual cells to colonize distant sites. It is the means by which non-invasive tumors progress into malignant, metastatic carcinomas. In vitro, EMT occurs in two steps. First, cells spread out, increasing in surface area and pushing the colony borders out. Then cells contract, pulling away from neighboring cells and rupturing cell-cell junctions, resulting in individual highly migratory cells. Recent discoveries indicate that calcium signaling is …


Evaluation Of Breastfeeding Curricula In Didactic Programs In Dietetics And Dietetic Internships Across The United States, Maria Diane Swiss Dec 2015

Evaluation Of Breastfeeding Curricula In Didactic Programs In Dietetics And Dietetic Internships Across The United States, Maria Diane Swiss

Theses and Dissertations

Background: Breastfeeding is known to have many benefits for both mothers and infants. With the Surgeon General's Call to Action to Support Breastfeeding, health professionals have increased their attention on breastfeeding competency. Objectives: This study aimed to evaluate breastfeeding curricula that are currently being covered in didactic programs in dietetics (DPDs) and dietetic internships (DIs) across the United States. Methods: Two-part surveys were sent to all directors of DPDs and DIs (n=475) with instructions to forward the second portion of the survey to instructors of classes that taught about breastfeeding. Qualtrics software was used for data …


Maternal Denning Phenology And Substrate Selection Of Polar Bears (Ursus Maritimus) In The Southern Beaufort And Chukchi Seas, Jay Wesley Olson Dec 2015

Maternal Denning Phenology And Substrate Selection Of Polar Bears (Ursus Maritimus) In The Southern Beaufort And Chukchi Seas, Jay Wesley Olson

Theses and Dissertations

Loss of sea ice due to global warming may affect the phenology and distribution of polar bear (Ursus maritimus) denning by altering access to denning habitats. We examined trends in the selection of maternal denning substrate (land versus sea-ice denning) in the southern Beaufort Sea (SB), addressing the potential influence of summer land-use and fall sea-ice conditions on substrate selection. We developed an algorithm based on statistical process control methods to remotely identify denning bears and estimate denning phenology from temperature sensor data collected on collars deployed 1985–2013 in the SB and Chukchi Sea (CS). We evaluated cub …


Diversification And Speciation Across Sundaland And The Philippines: The Effects Of 30 Million Years Of Eustatic Flux, Luke J. Welton Dec 2015

Diversification And Speciation Across Sundaland And The Philippines: The Effects Of 30 Million Years Of Eustatic Flux, Luke J. Welton

Theses and Dissertations

I highlight two squamate lineages endemic to Southeast Asia, the Asian water monitors (Varanus salvator Complex) and the Angle-headed lizards (Agamidae: Gonocephalus), and elucidate their systematic affinities and historical biogeography. My results represent novel phylogenetic inferences, with biogeographic histories and diversification events corresponding to major climatic fluctuations over the past 30 million years. Additionally, I solidify the taxonomy and systematics of the Varanus salvator Complex, and enumerate more than a dozen Gonocephalus lineages as candidate species in need of taxonomic scrutiny. Lastly, I investigate contemporary and historical patterns of dispersal throughout Sundaland, and between Sundaland and the Philippines.


Virulence Of Photorhabdus Spp.: Examining The Roles Of Environment, Evolution, And Genetics In Insect Mortality, Dana Blackburn Dec 2015

Virulence Of Photorhabdus Spp.: Examining The Roles Of Environment, Evolution, And Genetics In Insect Mortality, Dana Blackburn

Theses and Dissertations

Entomopathogenic nematodes (EPNs) (genera Heterorhabditis and Steinernema) kill their invertebrate hosts with the aid of a mutualistic bacterium. The bacteria (Xenorhabdus spp. for steinernematids and Photorhabdus spp. for heterorhabditids) are primarily responsible for killing the host and providing the nematodes with nutrition and defense against secondary invaders. Photorhabdus is a Gram-negative bacterium in the Enterobacteriaceae family with high virulence towards their insect hosts. To achieve high mortality rates Photorhabdus produces a variety of virulence factors such as toxins, lipases, proteases, secretion systems, and fimbriae. EPNs are amenable to laboratory rearing and mass production for biocontrol applications against insects …


Specialized Replication Operons Control Rhizobial Plasmid Copy Number In Developing Symbiotic Cells, Clarice Lorraine Perry Dec 2015

Specialized Replication Operons Control Rhizobial Plasmid Copy Number In Developing Symbiotic Cells, Clarice Lorraine Perry

Theses and Dissertations

The rhizobium – legume symbiosis is a complex process that involves genetic cooperation from both bacteria and plants. Previously, our lab described naturally occurring accessory plasmids in rhizobia that inhibit this cooperation. A transposon mutagenesis was performed on the plasmids to detect the genetic factor that blocked nitrogen fixation. Several of the plasmids were found to possess a replication operon that when disrupted by transposon insertion, restored symbiotic function. This study describes an in-depth investigation into one of those plasmids, pHRC377, and into its replication operon. The operon, which we have called repA2C2, comes from the repABC family of …


Stability Of Whole Wheat Flour, Rolled Oats, And Brown Rice During Long-Term Storage And Preparation, Victoria Elizabeth Scott Dec 2015

Stability Of Whole Wheat Flour, Rolled Oats, And Brown Rice During Long-Term Storage And Preparation, Victoria Elizabeth Scott

Theses and Dissertations

Whole grains are an increasingly popular health food in America. However, shelf life of whole grains is compromised due to the presence of lipoxygenases in the bran and germ, which lead to rancidity and generation of oxidative byproducts. These byproducts reduce sensory quality and may have a degradative effect on vitamins in whole grain products. The purpose of this study was to determine the degree of lipid and vitamin degradation during long-term storage of three whole grains: whole wheat flour, brown rice, and rolled oats. We also examined vitamin loss after cooking to determine if oxidative byproducts had an effect …


Water Use Of Four Commonly Planted Landscape Tree Species In A Semi-Arid Suburban Environment, Michael Cameron Bunnell Dec 2015

Water Use Of Four Commonly Planted Landscape Tree Species In A Semi-Arid Suburban Environment, Michael Cameron Bunnell

Theses and Dissertations

Native plant communities and agricultural land are commonly converted to urban areas as cities across the Western United States continue to grow and expand. This expansion is typically accompanied by afforestation where a common goal among communities is to maximize shade tree composition. Planted forests in these regions are commonly composed of introduced tree species native to mesic environments and their ability to persist is dependent on consistent irrigation inputs. Many potential ecosystem services may be derived from planting trees in urban and suburban areas; however, there are also costs associated with extensive afforestation, and shade tree cover may have …


The Effect Of Aerobic Exercise Versus Inactivity On Nitric Oxide Concentration And Synthesis In An Elderly Population, Samantha Burton Dec 2015

The Effect Of Aerobic Exercise Versus Inactivity On Nitric Oxide Concentration And Synthesis In An Elderly Population, Samantha Burton

Theses and Dissertations

CONTEXT: Nitric Oxide (NO) is an endothelial-derived vasoactive molecule that causes an increase in blood flow and oxygen delivery to tissue. A reduction in NO bioavailability has been found to occur in adults over the age of 60 and can be reversed pharmacologically by improving NO synthase (NOS) activity. Reversing these age-related changes with alternative interventions, such as aerobic exercise, has shown some promising results. OBJECTIVE: To quantify blood NO-bioavailability (as measured by blood nitrite levels) in a population of aerobically trained elderly men and compare these data to a group of age-matched, inactive individuals. In addition, we measured the …


Gene Networks Involved In Competitive Root Colonization And Nodulation In The Sinorhizobium Meliloti-Medicago Truncatula Symbiosis, Ryan D. Vanyperen Dec 2015

Gene Networks Involved In Competitive Root Colonization And Nodulation In The Sinorhizobium Meliloti-Medicago Truncatula Symbiosis, Ryan D. Vanyperen

Theses and Dissertations

The rhizobia-legume symbiosis is the most agriculturally significant source of naturally fixed nitrogen, accounting for almost 25% of all biologically available nitrogen. Rhizobia-legume compatibility restrictions impose limits on symbiotic nitrogen fixation. In many cases, the molecular basis for symbiotic compatibility is not fully understood. The signals required for establishing a symbiotic partnership between nitrogen-fixing bacteria (e.g. Sinorhizobium meliloti) and leguminous plants (e.g. Medicago truncatula) have been partially characterized at the molecular level. The first stage of successful root colonization is competitive occupation of the rhizosphere (which is poorly understood). Here, the bacteria introduce themselves as potential symbiotic partners …


Control Of Alternaria Solani Resistance To Boscalid, Fluopyram, And Chlorothalonil, Andrew K. Hollingshead Dec 2015

Control Of Alternaria Solani Resistance To Boscalid, Fluopyram, And Chlorothalonil, Andrew K. Hollingshead

Theses and Dissertations

Alternaria solani, cause of early blight, threatens potato yields. Fungicide resistance has made control of early blight difficult and there are concerns that in-season fungicide use results in resistance to boscalid, fluopyram, and chlorothalonil. Concern of high levels of resistance to boscalid a group 7 fungicide may confer cross-resistance to fungicides of the same group such as fluopyram. From 2014 to 2015, A. solani isolates were collected from field plots treated with boscalid, fluopyram, and chlorothalonil to test resistance levels. Isolates were determined resistant if EC50 values were higher than 5 µg ml-1. Boscalid and chlorothalonil mean EC50 values decreased …


The Effect Of Foot Strengthening Exercise On Dynamic Function Of The Medial Longitudinal Arch In Runners: A Preliminary Report, Jarom Bridges Dec 2015

The Effect Of Foot Strengthening Exercise On Dynamic Function Of The Medial Longitudinal Arch In Runners: A Preliminary Report, Jarom Bridges

Theses and Dissertations

Therapeutic exercise has previously been shown to alter the static height of the medial longitudinal arch (MLA). It is still unknown, however, if these effects carry over into dynamic activities. PURPOSE: To determine if an 8-week foot strengthening exercise program increases static arch height and reduces vertical deformation of the MLA during mid-stance in running.METHODS: Thirty-four recreational runners (17 males, 17 females) have completed this ongoing study (age 24.06 ± 3.61 years, body mass 68.63 ± 12.95 kg, and height 173.34 ± 9.54 cm). To date, 22 subjects have been assigned to the control group (8 weeks of normal running) …


Mountain Big Sagebrush (Artemisia Tridentata Ssp Vaseyana) Seed Production, Melissa L. Landeen Dec 2015

Mountain Big Sagebrush (Artemisia Tridentata Ssp Vaseyana) Seed Production, Melissa L. Landeen

Theses and Dissertations

Big sagebrush (Artemisia tridentata Nutt.) is the most widespread and common shrub in the sagebrush biome of western North America. Of the three most common subspecies of big sagebrush (Artemisia tridentata), mountain big sagebrush (ssp. vaseyana; MBS) is the most resilient to disturbance, but still requires favorable climactic conditions and a viable post-fire seedbank for successful unassisted recovery. This study was designed to assess MBS seed production throughout post-fire recovery. We performed 2 pilot studies to develop methods for estimating seed production and plant age. The results of the pilot studies and a space-for-time substitution strategy were used to measure …


The Anatomy Of Porcine And Human Larynges: Structural Analysis And High Resolution Magnetic Resonance Imaging Of The Recurrent Laryngeal Nerve, Nena Lundgreen Mason Nov 2015

The Anatomy Of Porcine And Human Larynges: Structural Analysis And High Resolution Magnetic Resonance Imaging Of The Recurrent Laryngeal Nerve, Nena Lundgreen Mason

Theses and Dissertations

The recurrent laryngeal nerve (RLN) innervates all the intrinsic muscles of the larynx that are responsible for human vocalization and language. The RLN runs along the tracheoesophageal groove bilaterally and is often accidentally damaged or transected during head and neck surgical procedures. RLN palsy and vocal cord paralysis are the most common and serious post op complications of thyroid surgeries. Patients who suffer from RLN injury can develop unilateral or bilateral vocal fold paralysis (BVFP). Theoretically, selective reinnervation of the posterior cricoarytenoid muscle would be the best treatment for BVFP. The phrenic nerve has been shown in several studies to …


The Detection And Molecular Evolution Of Francisella Tularensis Subspecies, Mark K. Gunnell Nov 2015

The Detection And Molecular Evolution Of Francisella Tularensis Subspecies, Mark K. Gunnell

Theses and Dissertations

Francisella tularensis is the etiological agent of tularemia, a zoonotic disease with worldwide prevalence. F. tularensis is a highly pathogenic organism and has been designated as a potential biothreat agent. Currently there are four recognized subspecies of F. tularensis: tularensis (type A), holarctica (type B), mediasiatica, and novicida. In addition, genomic studies have further subdivided type A tularensis into two subclassifications, type A.I and type A.II. These two subclassifications differ in geographic distribution with type A.I appearing mainly in the Eastern United States and type A.II appearing mainly in the Western United States. Because of differences of virulence among the …


Strength Training And Body Composition In Middle-Age Women, Rachelle Burrup Nov 2015

Strength Training And Body Composition In Middle-Age Women, Rachelle Burrup

Theses and Dissertations

OBJECTIVE: The purpose of this study was to examine the relationship between strength training and body composition before and after controlling for several covariates. A cross-sectional study including 257 female subjects was conducted. METHODS: Subjects' level of involvement in strength training was determined via questionnaire. Body composition was assessed using dual energy X-ray absorptiometry (DXA). Diet was assessed using 7-d weighed food records. RESULTS: Strong linear relationships between subjects' level of involvement in strength training and body composition were identified. For each additional day of strength training reported per week, body fat was 1.32 percentage points lower (F = 14.8, …


Image-Charge Detection €“ Novel Instrumentation And Applications, Brandon Lee Barney Oct 2015

Image-Charge Detection €“ Novel Instrumentation And Applications, Brandon Lee Barney

Theses and Dissertations

Image-charge detection is an analytical technique in which a highly-charged particle is detected by the magnitude of the image current that it generates in a detecting electrode. This current is represented as a voltage between the charged particle and the sensing electrode. It is a single particle detection method, ideal for the analysis of large, variable mass particles such as biological cells. Some of the physical properties of Bacillus subtilis spores were explored using different applications of image-charge detection. B. subtilis is a gram-negative spore-forming bacteria that has been shown to exhibit extremophile behavior. The particular extremophile behavior that was …


Repeated Trait Evolution Driven By Divergent Natural Selection At Early And Late Stages Of Speciation, Spencer J. Ingley Oct 2015

Repeated Trait Evolution Driven By Divergent Natural Selection At Early And Late Stages Of Speciation, Spencer J. Ingley

Theses and Dissertations

Speciation – the process by which new species arise – is of fundamental importance in the biological sciences. The means by which new species arise, and the relationship among living species, has been a topic that has captivated both lay and scientific observers for centuries. In recent years, the study of speciation has enjoyed increased attention, resulting in significant advances in our understanding of how species form. Although our understanding of the processes that contribute to speciation has increased dramatically in recent years, our knowledge of how reproductive barriers accumulate as speciation proceeds is still limited. Thus, studies that evaluate …


Selection And Use Of Pantoea Dispersa Strain Jfs As A Non-Pathogenic Surrogate For Salmonella Typhimurium Phage Type 42 In Flour, James R. Fudge Aug 2015

Selection And Use Of Pantoea Dispersa Strain Jfs As A Non-Pathogenic Surrogate For Salmonella Typhimurium Phage Type 42 In Flour, James R. Fudge

Theses and Dissertations

Salmonella, a common food pathogen, costs more than any other pathogen in the United States in terms of health care costs and loss of work due to the illnesses it causes. Low-moisture foods, especially flour, are susceptible to being contaminated by Salmonella. Food producers want flour to be pathogen-free but to also retain the same functionality of non-treated flour. Heat treatment is the most common method employed for lowering the concentration of pathogens in food. However, heating can result in the loss of the flour’s functionality. Pantoea dispersa strain JFS has been isolated from flour as a nonpathogenic bacterial surrogate …


Delimiting Species And Varieties Of Cycladenia Humilis (Apocynaceae), Holly Kathryn Brabazon Jul 2015

Delimiting Species And Varieties Of Cycladenia Humilis (Apocynaceae), Holly Kathryn Brabazon

Theses and Dissertations

Taxonomic delimitation of rare species is vital for accurate assessments of diversity and for their conservation. Cycladenia humilis, the sole species of Cycladenia, is an enigmatic perennial widely dispersed across the western United States. Within this species there are three currently recognized varieties: C. humilis var. humilis in Northern California, C. humilis var. venusta in Southern California, and C. humilis var. jonesii in Utah and Northern Arizona. Some populations occur geographically in areas between the typical distribution of each variety and the presently accepted taxonomy inadequately addresses these populations. Using five nDNA regions, we seek to clarify relationships between current …


Drought And Nitrogen Effects On Maize Canopy Temperature And Stress Indices, David A. Carroll Jul 2015

Drought And Nitrogen Effects On Maize Canopy Temperature And Stress Indices, David A. Carroll

Theses and Dissertations

Increased water scarcity due to changing climate, population growth, and economic development is a major threat to the sustainability of irrigated agriculture in the Western United States and other regions around the world. Management practices, such as controlled deficit irrigation, that seek to maximize the productivity of a limited water supply are critical. When using controlled deficit irrigation, remote sensing of crop canopy temperature is a useful tool for assessing crop water status and for more precise irrigation management. However, there is potential that nutrient deficiencies could compound the interpretation of water status from leaf temperature by altering leaf color …


Histone Deacetylase 6 (Hdac6) Is Critical For Tumor Cell Survival And Promotes The Pro-Survival Activity Of 14-3-3Ζ Viadeacetylation Of Lysines Within The14-3-3Ζ Binding Pocket, Jeffrey Benjamin Mortenson Jul 2015

Histone Deacetylase 6 (Hdac6) Is Critical For Tumor Cell Survival And Promotes The Pro-Survival Activity Of 14-3-3Ζ Viadeacetylation Of Lysines Within The14-3-3Ζ Binding Pocket, Jeffrey Benjamin Mortenson

Theses and Dissertations

Our understanding of non-histone acetylation as a means of cellular regulation is in its infancy. Using a mass spectrometry approach we identified acetylated lysine residues and monitored acetylation changes across the proteome as a consequence of metabolic stress (hypoxia). We observed changes in acetylation status of non-histone lysines in tumor cells. Through the use of small molecule inhibitors of histone deacetylase enzymes (HDACs) and siRNA screening identified HDAC6 as a pro-survival regulator of lysine acetylation during hypoxia. The phospho-binding protein 14-3-3ζ acts as a signaling hub controlling a network of interacting partners and oncogenic pathways. We show here that lysines …


Mating-Type Locus Characterization And Variation In Pyrenophora Semeniperda, Julie Leanna Henry Jul 2015

Mating-Type Locus Characterization And Variation In Pyrenophora Semeniperda, Julie Leanna Henry

Theses and Dissertations

Pyrenophora semeniperda is a generalist fungal pathogen that occurs primarily on monocot seed hosts. It is in the phylum Ascomycota, which includes both self-compatible (homothallic) and self-incompatible (heterothallic) species. Homothallic fungal species contain complementary mating-type (MAT) idiomorphs in a single unikaryotic strain, while heterothallic strains contain a single MAT idiomorph requiring interaction between strains of complementary mating-types for sexual reproduction to occur. Because the majority of P. semeniperda strains contained either MAT1 or MAT2, this species was provisionally categorized as heterothallic. However, many strains contain both MAT idiomorphs and appear to be homothallic. These results warranted a closer look at …


Evaluation Of A Combination Approach To Pedagogy In A Soil Science Laboratory Classroom And An Environmental Site Assessment Sample, Emily Linda Gervais Jul 2015

Evaluation Of A Combination Approach To Pedagogy In A Soil Science Laboratory Classroom And An Environmental Site Assessment Sample, Emily Linda Gervais

Theses and Dissertations

Chapter 1 of this study explores research that has shown that the use of technology in the classroom can be beneficial to student learning. Additionally, a need for Environmental Site Assessment (ESA) instruction in university level core environmental science classrooms has been demonstrated. This study includes an investigation of the potential benefits of using a combination of pedagogies: web-based teaching tools and ESA instruction in a laboratory classroom. The research design included two class formats, one that employed web-based tools (PowerPoint and video) and ESA instruction, and one that did not, with four class sections. All classes were taught by …


Indications Of Ancient Maya Soil Resource Management In Northern Belize, Austin Michael Ulmer Jul 2015

Indications Of Ancient Maya Soil Resource Management In Northern Belize, Austin Michael Ulmer

Theses and Dissertations

The objective of this study was to use soil chemical properties, particularly carbon isotopes to describe the agricultural landscape in the Blue Creek region on the Rio Bravo Escarpment in northwestern Belize. The primary question associated with this study focused on the comparative agricultural potential of the soils between the upland karst environment and the lowland coastal plains using the distribution and frequency of ancient Maya maize production. Soil physical features, such as clay concentrations throughout profiles in conjunction with soil chemical properties were used to aid in determining the level of ancient maize production. Isotopic evidence suggests that anciently, …


Analytical Approaches In Investigating The Kinetics Of Water-Molecule Complexes In Tropospheric Reactions, William J. Keeton Jul 2015

Analytical Approaches In Investigating The Kinetics Of Water-Molecule Complexes In Tropospheric Reactions, William J. Keeton

Theses and Dissertations

Ozone is a heavily monitored pollutant. Ozone is not directly emitted into the atmosphere, but rather the product of chemical reactions. Ground level ozone occurs when nitrogen oxides (NOx) and volatile organic compounds (VOCs) react with each other in the presence of sunlight. The primary precursors of ozone are anthropogenically emitted, and as a result, tropospheric ozone has cost millions of dollars in damages and has hurt the health of countless people. This dissertation is a collection of work that aims to provide insight into atmospheric reactions that result in tropospheric ozone and the instrumentation to study such reactions. While …