Physical Sciences and Mathematics Commons^™

Production And Applications Of Formaldehyde-Free Phenolic Resins Using 5-Hydroxymethylfurfural Derived From Glucose In-Situ, Yongsheng Zhang

Electronic Thesis and Dissertation Repository

The phenol-formaldehyde (PF) resin manufacturing industry is facing a growing challenge with respect to concerns over human health, due to the use of carcinogenic formaldehyde and sustainability due to the use of petroleum-based phenol in PF resin manufacture. Glucose and its derivative, 5-hydroxymethylfurfural (5-HMF), have proven to be potential substitutes for formaldehyde in the synthesis of phenolic novolac resins.

This thesis investigated a number of glucose and 5-HMF resin systems including the curing of phenol-glucose novolac resin (PG) with a bis-phenol-A type epoxy. The curing process was modeled according to the Sestak-Berggren equation (S, B) using Málek methods. This was …

Response Of Soil Nitrification To The Veterinary Pharmaceuticals Monensin, Ivermectin And Zinc Bacitracin, Magda A. Konopka

Electronic Thesis and Dissertation Repository

Pharmaceutical residues can reach agricultural land through amendment with animal or human waste. Since 2010, a series of replicated plots received annual applications of ivermectin, monensin and zinc bacitracin, either singly or in a mixture, at 0.1 mg/kg and 10 mg/kg concentrations. I collected soil samples before and after the fourth annual application of pharmaceuticals and assayed them for functional changes and amoA gene abundance, a gene needed for ammonia oxidation. In 2013, I exposed the soils to 100 mg/kg in a laboratory experiment which resulted in acceleration of nitrification. Under 10 mg/kg treatments in the field the abundance of …

Methods For Identifying Regions Of Brain Activation Using Fmri Meta-Data, Meredith A. Ray

Theses and Dissertations

Functional neuroimaging is a relatively young discipline within the neurosciences that has led to significant advances in our understanding of the human brain and progress in neuroscientific research related to public health. Accurately identifying activated regions in the brain showing a strong association with an outcome of interest is crucial in terms of disease prediction and prevention. Functional magnetic resonance imaging (fMRI) is the most widely used method for this type of study as it has the ability to measure and identify the location of changes in tissue perfusion, blood oxygenation, and blood volume. In practice, the three-dimensional brain locations …

Examining The Effectiveness Of Ecotourism As A Funding Source For Protected Area Management In Guyana, Jordan S. Flagel

Masters Theses, 2010-2019

Protected areas in tropical rainforests serve many important ecosystem services, including carbon sequestration. These areas are often in need of donor or grant funding to operate as governments in tropical forested countries are not always able to provide adequate funds for protection. This paper focuses on the Iwokrama International Center for Rainforest Conservation and Development in the South American country of Guyana, which has had funding issues since the global economic crisis of 2008 and an accompanying shift in donor country financial priorities. Increasing the amount of sustainable ecotourism in the Iwokrama reserve was identified as a potential source for …

Colloidal And Biological Properties Of Triscationic Amphiphiles With One Or Two Tails, John N. Marafino

Masters Theses, 2010-2019

The decline in the development of novel antimicrobials, combined with the misusage and over prescription of antibiotics, has contributed to the increasing prevalence of antimicrobial-resistant infections. Thus development of effective novel disinfectants could reduce the transmission of pathogens and decrease the risk of infection by antibiotic resistant organisms. The antimicrobial activity of amphiphiles, compounds with hydrophobic and hydrophilic regions, was first reported in 1935, and has influenced the synthesis of amphiphiles with variations in structure. In this study, three series of amphiphiles were synthesized by two subsequent Menshutkin reactions. Each amphiphile contains one or two hydrocarbon tails ranging from 8 …

Reproductive Parameters Of Two Coastal Pelagic Fishes Off Southeast Florida: Blackfin Tuna Thunnus Atlanticus And Little Tunny Euthynnus Alletteratus, Sonia Ahrabi-Nejad

HCNSO Student Theses and Dissertations

The ability to manage a fish stock relies on an understanding of life history characteristics and basic biology of the species. Numerous age-growth studies are facilitated by the relative ease of ageing fishes through hard-part analyses. Determining reproductive parameters for fish populations is equally important for stock assessments and management, and histological examination of gonads provides the most accurate determination of fecundity and spawning periods. Coastal pelagic fishes are often targeted commercially and recreationally due to their easy access by private vessels. However, there are few studies researching the biology and reproduction of recreational fishes in the waters of Southeastern …

Changes In Coral Community Composition At Devil's Crown, Galapagos Islands, Ecuador: A 7,700 Year Perspective, Katharine Jane Hendrickson

HCNSO Student Theses and Dissertations

Coral mortality caused by El Niño–Southern Oscillation (ENSO) activity and its related disturbances has been researched throughout the Eastern Pacific. In the past three decades, disturbances related to the El Niño–Southern Oscillation (ENSO) have been shown to influence coral growth in the Eastern Pacific. In the Galápagos Islands, Ecuador, more than 97% of corals experienced mortality after the severe 1982-1983 ENSO episode. However, two of the most dominant coral species found in a coral community adjacent to Devil’s Crown; Psammocora stellata and Diaseris distorta survived this severe ENSO event. By reconstructing sediment cores of the coral community, this study assessed …

Distribution, Growth, And Impact Of The Coral-Excavating Sponge, Cliona Delitrix, On The Stony Coral Communities Offshore Southeast Florida, Ari Halperin

HCNSO Student Theses and Dissertations

Bioerosion is a major process that affects the carbonate balance on coral reefs, and excavating sponges from the genus Cliona are some of the most important bioeroders on Caribbean reefs. The orange boring sponge, Cliona delitrix, is an abundant excavating sponge offshore southeast Florida that frequently colonizes dead portions of live stony corals, killing live coral tissue as it grows. With the recent decline in coral cover attributed to combined environmental and anthropogenic stressors, the increasing abundance of excavating sponges poses yet another threat to the persistence of Caribbean coral reefs.

In the first part of this study, I …

Assessment Of Macroinvertebrate Communities And Heavy Metal Contamination Along The Intracoastal Waterway In Fort Lauderdale, Florida, Robert Bernhard

HCNSO Student Theses and Dissertations

Sediments from four areas adjacent to marinas and a background site in the Intracoastal Waterway were assessed for macroinvertebrate composition and heavy metal contamination. Sediment core samples were collected in 2004 and 2005 for analyses of macroinvertebrate composition and sediment grain size. Additional sediment samples were collected in 2005 for chemical analyses of metals (Al, As, Cd, Cr, Cu, Fe, Pb, Hg, Ni and Zn). MANOVA and dendograms using Bray-Curtis similarity matrices grouped the sites into two clusters: the 3 sites closest to the New River formed one group, and the two end sites formed the other. The sites nearest …

Wildwood/Kraemer Lake County Park Observational Study: The Effects Of Fragmentation On Old-Growth Forest Species, Rhonda H. Zimmerman

Culminating Projects in Biology

Habitat fragmentation generates forest fragments with increased ratio of "edge". This "edge effect" alters the natural community. Old growth forests support deep forest communities which rely on the closed canopy for survival, often indicators of healthy old growth communities. Putative old growth forest patches were identified in Wildwood Park and St. John’s Arboretum/University. One study objective was to collect baseline data on flora and fauna in Wildwood to confirm the presence of old-growth patches. The main ecological goal of the study was to determine if bird and plant communities exhibited patterns consistent with the operating assumption of 50 acre old-growth …

Fresh Bytes - Connected Hydroponics For Small-Scale Growing, Jack Bowen

Liberal Arts and Engineering Studies

Many users are now transitioning to small-scale hydroponics and aquaponics at home. There can be a barrier to entry with these systems as there is a delicate balance of chemicals, pH, etc. that must be maintained. There are sensors for these various components but they are either aimed at commercial production or are un-automated. Fresh Bytes is a microcomputer with sensors to detect all of these unseen components in a hydroponic system. A prototype of this microcomputer is produced along with CAD plans for more professional versions of it. The sensors are verified and future development is contemplated.

Phosphorus Recycling By Profunda Quagga Mussels In Lake Michigan, Caroline Mosley

Theses and Dissertations

Quagga mussels (Dreissena rostiformis bugensis) act as ecosystem engineers in the southern basin of Lake Michigan, altering physical habitats and biogeochemical processes. Adapted to cold and oligotrophic conditions, profunda quagga mussels thrive on the soft substrate of deeper depths. At a 55 m site (10,000 mussels m-2) offshore from Milwaukee, WI, profunda mussel biomass (g m-2) was 1/3 of biomass (g m-2) measured at a 10 m comparison site (5,000 mussels m-2). Higher densities but less biomass is due to profunda mussels having less tissue for a given length and the population per m2 comprising of mostly small mussels ( …

An Optimization Method For Estimating Joint Parameters Of The Hip And Knee, Ben Tesch

Theses and Dissertations

Biomechanics, generally speaking, concerns the application of engineeringprinciples to the study of living things. This work is concerned withhuman movement analysis, a subfield of biomechanics, where the methodsof classical mechanics are applied to human movement. This field hascontributed to the general understanding of human movement, and itstechniques are used in the diagnosis and treatment of disease. Centralto the field is the process of measuring human movement. Since classicalmechanics deals with the motion of rigid bodies, and ideal measurementsystem would be able to accurately record the exact pose --- combinedposition and orientation --- of the bones. The techniques that reachthis ideal …

Photoelectric Characterization Of Bacteriorhodopsin Reconstituted In Lipid Bilayer Membrane, Joel Kamwa

Graduate Theses and Dissertations

The objective of this work was to conduct basic research in biologically inspired energy conversion solutions. A photosynthetic protein (Bacteriorhodopsin) was reconstituted in a bi-layer membrane. Then, when a laser beam was shined on the membrane, the photon energy was used by the protein to pump protons across the membrane. The translocation of protons across the membrane was measured as photocurrent. For this purpose, a system was built to characterize the lipid bilayer membranes and to measure the photocurrent. The lipid bilayer membrane was characterized by its capacitance and resistance. A picoampere photocurrent was observed when Bacteriorhodopsin protein was present …

Oligomerization Of The Sterile-2 G-Protein Coupled Receptor In Yeast Cells In The Presence And Absence Of Alpha-Factor Pheromone Using Fluorescence Spectroscopy And Forster Resonance Energy Transfer Analysis, Joel David Paprocki

Theses and Dissertations

G-protein-coupled receptors (GPCRs) are the largest family of receptors that respond to a wide variety of extracellular stimuli, including molecular ligands such as odorants, neurotransmitters, and hormones, as well as physical agents sigh as light and pressure. The stimulation event results in initiating conformational changes in the structure of the receptor, which further results in the release of the heterotrimeric G-protein; the latter has a variety of functions within signaling pathways in cellular biology. The GPCR explored in this investigation is the Sterile 2 α-factor receptor (Ste2), whose natural function is that of a yeast mating pheromone receptor. Its natural …

Using Migration Monitoring Data To Assess Bird Population Status And Behavior In A Changing Environment, Evan M. Adams

Electronic Theses and Dissertations

Across the world, researchers use migration banding stations to document bird migration and study the phenomenon. In this dissertation, I focus on ways of analyzing bird migration banding data and the utility migrating birds as indicators of ecosystem health that make these monitoring efforts more useful to answering ecological questions and managing migratory species. In Chapter 1, we provide background on hierarchical modeling and an overview of our findings. In Chapter 2, we developed and validated new methods to estimate daily changes in migratory population size while controlling for changes in detectability due to environmental conditions. In Chapter 3, this …

The Economic Viability Of Cocoa Crop Insurance In Ghana, Justin D. Mckinley

Graduate Theses and Dissertations

This study was motivated by the fact that Ghanaian cocoa producers face lower yields than other main cocoa producing counties which in turn increases food insecurity for smallholder producers. In addition, low yields experienced by Ghanaian producers is a driving factor for forest degradation and deforestation as cocoa producers encroach further into previously undisturbed forests in efforts to increase their incomes. There are currently production methods to achieve higher yields readily available in Ghana; however, many producers choose not to adopt these methods because they are seen as too risky, or simply cannot adopt them due to financial/credit constraints. A …

Ultrafast Interfacial Electron Transfer Across Molecule-Tio2 Nanocomposites: Towards Solar Cells And Two Photon Absorption, Edwin Mghanga

Dissertations

Interfacial charge transfer (ICT) across the molecule-TiO2 nanoparticle interface has gained enormous research attention for applications in dye sensitized solar cells (DSSC), photo-catalysis, water splitting and nonlinear optics. DSSCs are promising clean alternative energy sources. However, current DSSCs suffer from lower efficiencies and higher cost. Better understanding of the ICT processes in DSSCs can help solve these problems. We have used two strategies to understand ICT in the context of DSSCs. Firstly, we used a computationally validated anchor group, acetylacetonate (acac) to bind molecules to the semiconductor surface and facilitate charge separation. Secondly, we used natural dye sensitizers, …

Identification And The Significance Of Selective Proteins In Bile And Plasma Of Normal And Health-Compromised Chickens, Balamurugan Packialakshmi

Graduate Theses and Dissertations

During the last 50 years, animal breeding programs in commercial poultry have made significant progress in the bodyweight gain of broilers but led to several metabolic and skeletal disorders. Lameness associated with proximal femur known as femoral head separation (FHS) or femoral head necrosis (FHN) is one of the major metabolic disorders in poultry industry. In order to select for healthy chickens, markers that can distinguish between healthy and affected birds are required. Biomarkers from blood represent an ideal and rich source of markers which can be obtained using minimally invasive methods. The biomarkers were explored in an experimental model …

Short-Term Effects Of Poultry Litter Or Woodchip Biochar Amendment In A Temperate Zone Agronomic System, Katy Elizabeth Brantley

Graduate Theses and Dissertations

Biochar, a charcoal product produced by the anaerobic thermal decomposition of biomass, can provide agronomic benefits when soil applied. However, research is lacking in temperate region soils investigating specific biochar products and their effects on agronomically important crops. A greenhouse study utilizing poultry litter biochar and a field study utilizing pine woodchip biochar were conducted to observe the effects of biochar application to Northwest Arkansas soils on corn growth and nutrient availability. A third experiment investigated poultry litter and pine woodchip biochar influences on soil water retention. In all three experiments, biochar was applied at three rates (0, 5, and …

Oxidative Stability Of Conjugated Linoleic Acid Rich Soy Oil Obtained By Heterogeneous Ruthenium Catalysis, Saurabh Ravindra Lele

Graduate Theses and Dissertations

Conjugated linoleic acid (CLA) has multiple health benefits but it is difficult to obtain sufficient CLA in a healthy diet to obtain the clinical effects. A CLA rich-soy oil (CLARSO) with up to 20% CLA has been produced by heterogenous catalysis but no studies of its oxidative stability have been reported. CLARSO and soy oil primary and secondary oxidation products were measured at 50oC in the dark. The CLARSO was less stable than soy oil but adsorption bleaching improved its oxidative stability. However, induction times were dependent on the analytical method used. Fatty acid oxidation kinetics was determined by measuring …

Switchgrass Cultivar, Harvest Frequency, Fertilizer Source, And Irrigation Effects On Near-Surface Soil Properties In West-Central Arkansas, Alayna A. Jacobs

Graduate Theses and Dissertations

Switchgrass (Panicum virgatum L.) has been identified as a model bioenergy feedstock crop and is expected to become an important feedstock for future renewable fuel generation. Agronomic management combinations that maximize monoculture switchgrass yield are generally well understood; however, little is known about corresponding effects of differing switchgrass management combinations on near-surface soil properties. The objective of this research was to determine the residual near-surface soil property effects of three years (2008 to 2011) of consistent management combinations to maximize switchgrass biomass production, including cultivar (‘Alamo’ and ‘Cave-in-Rock’), harvest frequency (1-cut and 2-cut systems per year), fertilizer source (poultry …

Cellular Zinc Trafficking: The Zinc Proteome And Its Reactions With Cadmium, Mohammad Ali Namdarghanbari

Theses and Dissertations

Metals play a crucial role in living systems. Iron, zinc, copper, molybdenum, and manganese are involved in many essential biological activities. Among transition metals, zinc after iron is the most abundant transition metal in the human body and the most abundant in the brain. It exists in more than 3000 proteins, which comprise about 10% of the human proteome. Zn2+ dyshomeostasis is associated with chronic diseases such as metabolic syndrome, diabetes and related complications, bone loss, growth retardation in young children, and neurological and behavioral problems. Despite a good knowledge obtained for metabolism of some metal ions such as copper, …

Part I: Synthesis And Biological Evaluations Of Potent Class L Selective Histone Deacetylase Inhibitors Part Ii: Aqueous Complexes For Efficient Sizebased Separation Of Americium From Curium Part Iii: Designing Strong Chiral Bronsted Acids And Their Application For Oxaxinanones Derivatization And The Aza-Henry Reaction, Joseph Steve Ulicki

Theses and Dissertations

PART I: SYNTHESIS AND BIOLOGICAL EVALUATIONS OF POTENT CLASS l SELECTIVE HISTONE DEACETYLASE INHIBITORS

Histone deacetylase inhibitors (HDACi) have found a wide variety of medicinal uses and are most noted for their specific apoptotic action towards cancer cells1. Several hydroxamates and tetrapeptides HDACi have since been moved on to phase 1 and 2 clinical trials, with FK228 & SAHA having already been approved for treatment of advanced cutaneous T-cell lymphoma (CTCL). FK228 & SAHA are pan-HDACi which d compounds describes the unselective inhibition for any of the 11 Zn2+-dependent HDAC isoforms. Research in the past five years, has shifted towards …

Applications Of A New Geodata Crawler For Landscape Ecology: From Mapping Natural Stream Hydrology To Monitoring Endangered Beetles, Douglas Ryan Leasure

Graduate Theses and Dissertations

An investigation of endangered American burying beetle (Nicrophorus americanus) ecology led to development of a Geodata Crawler with applications in eco-hydrology. Geodata Crawler includes a national GIS (geospatial information systems) database with layers that quantify climate, land cover, soils, human development, and other attributes of the biosphere. For user-locations in the continental United States, Geodata Crawler can rapidly tabulate site-specific statistics within automatically delineated sample areas: points, site radii, watersheds, and riparian zones, among others. Geodata Crawler supported a multi-scale analysis of N. americanus habitat at a military installation in western Arkansas to produce a Landsat-based monitoring tool. Royle's N-mixture …

Measuring The Role Of Inhibition In Auditory Discrimination In Mice, Tazima Nur

Graduate Theses and Dissertations

Understanding how inhibitory neurons affect sensory information processing in the cerebral cortex is an ongoing goal of both neuroscience and statistical physics research. In this master's thesis research project, an experimental system has been designed and built for studying how auditory dynamic range depends on inhibitory neurons, based on observations of mouse behavior. In this thesis, firstly, the topic of inhibition and information processing has been introduced. Then two papers related to inhibition and dynamic range has been reviewed in detail. One of the papers is an experimental work that analyzes the affect of inhibition on dynamic range. The other …

Chaperone-Mediated Folding And Assembly Of Β-Propeller Proteins Into Cellular Signaling Complexes, Rebecca L. Plimpton

Theses and Dissertations

G protein signaling depends on the ability of the individual subunits of the G protein heterotrimer to assemble into a functional complex. Formation of the G protein βγ (Gβγ) dimer is particularly challenging because it is an obligate dimer in which the individual subunits are unstable on their own. Recent studies have revealed an intricate chaperone system that brings the Gβ and Gγ subunits together. This system includes the cytosolic chaperonin containing TCP-1 (CCT) and a co-chaperone phosducin-like protein 1 (PhLP1). Two key intermediates in the Gβγ assembly process, the Gβ-CCT and the PhLP1-Gβ-CCT complexes, were isolated and their structures …

Atom-Based Geometrical Fingerprinting Of Conformal Two-Dimensional Materials, Mehrshad Mehboudi

Graduate Theses and Dissertations

The shape of two-dimensional materials plays a significant role on their chemical and physical properties. Two-dimensional materials are basic meshes that are formed by mesh points (vertices) given by atomic positions, and connecting lines (edges) between points given by chemical bonds. Therefore the study of local shape and geometry of two-dimensional materials is a fundamental prerequisite to investigate physical and chemical properties. Hereby the use of discrete geometry to discuss the shape of two-dimensional materials is initiated.

The local geometry of a surface embodied in 3D space is determined using four invariant numbers from the metric and curvature tensors which …

The Response Of Cotton (Gossypium Hirsutum L.) To Slow Release Foliar Fertilization And The Effect Of Environment On Absorption, James Matthews Burke

Graduate Theses and Dissertations

In cotton production, nitrogen (N) is the most limiting nutrient and the demand is substantial. Foliar-N fertilization is regarded as an effective and environmentally sound method of supplying cotton with N during times of deficiency and high demand. In response to the potential benefits of the foliar-N fertilization of cotton, a myriad of foliar-N based fertilizers have been created; each with their own individual chemical technology and constitution. Experiments were performed with the objectives of examining the effects of the slow-release foliar-N fertilizer, Nitamin® (1) on the growth and development of field-grown cotton, (2) on uptake under various environmental conditions, …

Alkaline Hydrolyzable-Nitrogen, Seeding Date, And Clay-Fixed Ammonium As Potential Indicators Of Rice Response To Nitrogen Fertilization In Arkansas, Anthony Michael Fulford

Graduate Theses and Dissertations

Several potential indicators of rice (Oryza sativa L.) response to nitrogen (N) fertilization include the soil<&rsquos>s alkaline hydrolyzable<&minus>N (AH<&minus>N) concentration, seeding date, and the soil<&rsquos>s clay<&minus>fixed NH₄<&ndash>N content. Three studies were conducted to: (1) correlate AH<&minus>N, determined using Illinois Soil Nitrogen Test (ISNT) or Nitrogen Soil Test for Rice (N<&minus>STaR), to plant parameters of interest and develop a fertilizer N rate calibration curve capable of predicting the 95% relative grain yield (RGY) fertilizer N rate for rice grown on clayey soils; (2) evaluate the influence of seeding date and N …