Digital Commons Network^™

Determining The Trophic Role Of Red Snapper (Lutjanus Campechanus) In Mississippi State Waters Using Stomach Content And Stable Isotope Analysis, Branden Kohler

Master's Theses

The goal of this study was to determine the diet composition, trophic position and ecological role of red snapper (Lutjanus campechanus) in Mississippi state waters utilizing stable isotopes (δ¹³C and δ¹⁵N) and stomach content analysis. Stable isotope analysis of fish and their prey can provide information on species-specific basal resource utilization, diet composition and trophic position which can improve food web models and inform fisheries management decisions. Particulate organic matter (POM), the presumed base of the food web, red snapper muscle tissue, and red snapper stomach contents were collected from 25 sites in 2016 and …

Telescope Parallel Actuator Mount: Control And Testing, Samuel S. Artho-Bentz

Master's Theses

This thesis approaches the task of designing a control system for the Parallel Actuator Mount developed by Dr. John Ridgely and Mr. Garrett Gudgel. It aims to create a base framework that directly controls the telescope and can be expanded to accept external command. It incorporates lower priced components and develops more easily approachable software with great functionality. An open-loop method for velocity control is established. Developing repeatable tests is a major focus. Testing finds the control methods developed result in velocity error of less than 5% and position error of less than 1.5% despite several mechanical issues and inaccuracies. …

A Quantitative Approach For Tuning A Mountain Bike Suspension, Steven Robert Waal

Master's Theses

A method for tuning the spring rate and damping rate of a mountain bike suspension based on a data-driven procedure is presented. The design and development of a custom data acquisition system, known as the "MTB DAQ," capable of measuring acceleration data at the front and rear axles of a bike are discussed. These data are input into a model that is used to calculate the vertical acceleration and pitching angular acceleration response of the bike and rider. All geometric and dynamic properties of the bike and rider system are measured and built into the model. The model is tested …

Lc-Ms/Ms Method Development For The Quantitation Of Methylmalonic Acid Using Aqueous Normal Phase Chromatography, Daniel Joseph Biocini

Master's Theses

The aim of the study was to develop a quantitative assay for methylmalonic acid (MMA), an important biomarker for clinical diagnosis of vitamin B12 (B12) deficiency. The techniques of liquid chromatography and tandem mass spectrometry (LC-MS/MS) are used for separation and quantitation of MMA, as well as its endogenous isomer succinic acid. The MS/MS method was developed using an infusion set-up and manual tuning experiments. Relevant transitions were detected for the two analytes and MMA-d3, then a preliminary MS/MS method was developed. The preliminary LC method was further optimized. Various gradients, mobile phases (MPs), and additive combinations were used across …

Using Machine Learning To Predict Sag And Leveling Behavior Of Interior Architectural Paints, Ethan Kim

Master's Theses

In the world of interior architectural paints, rheology, or the deformation and flow of a fluid, is one of the largest economic and development hurdles for paint formulators. To achieve maximum functionality, coverage, and economy of product, the rheology of the coating must be properly optimized, balancing performance while minimizing undesirable flow defects such as paint sagging or visible brush and roller marks; these visual imperfections are associated with the sag and leveling properties of the paint. Many researchers have attempted to develop a better understanding of sag and leveling, either by drawing correlations or through mathematical derivation; however, neither …

Transgenerational Plasticity Causes Differences In Uv-Tolerance Of Intertidal And Subtidal Populations Of The Purple Sea Urchin, Strongylocentrotus Purpuratus, Yareli Alvarez, Nikki L. Adams

Master's Theses

Planktonic larvae of marine organisms are increasingly being exposed and required to respond to a changing physical environment. Adult sea urchins occupy both intertidal and subtidal waters and broadcast spawn gametes into the water column to contend with variable physical conditions. To answer how populations of invertebrates residing at different depths adequately prepare their offspring to cope with different levels of ultraviolet radiation (UVR), we collected adult purple sea urchins, Strongylocentrotus purpuratus, from four sites (two intertidal and two subtidal (~15 m deep)) on the central coast of CA to compare UV tolerance in offspring. Our measurements of UVA …

Development Of Zeolitic Imidazolate Frameworks For Enhancing Post-Combustion Co2 Capture, Dustin Lee

Master's Theses

Post-combustion CO₂ capture is a promising approach for complementing other strategies to mitigate climate change. Liquid absorption is currently used to capture CO₂ from post-combustion flue gases. However, the high energy cost required to regenerate the liquid absorbents is a major drawback for this process. As a result, solid sorbents have been investigated extensively in recent years as alternative media to capture CO₂ from flue gases. For example, metal organic frameworks (MOFs) are nanoporous materials that have high surface areas, large pore volumes, and flexible designs. A large number of MOFs, however, suffer from 1) low CO …

Sensory Stressors Impact Species Responses Across Local And Continental Scales, Ashley A. Wilson

Master's Theses

Pervasive growth in industrialization and advances in technology now exposes much of the world to anthropogenic night light and noise (ANLN), which pose a global environmental challenge in terrestrial environments. An estimated one-tenth of the planet’s land area experiences artificial light at night — and that rises to 23% if skyglow is included. Moreover, anthropogenic noise is associated with urban development and transportation networks, as the ecological impact of roads alone is estimated to affect one-fifth of the total land cover of the United States and is increasing in space and intensity. Existing research involving impacts of light or noise …

A Water Balance And Sediment Yield Analysis Model For The Lopez Lake Reservoir, Lee Joon Faraca

Master's Theses

Lopez Lake Reservoir is the primary source of potable water for the Cities of Arroyo Grande, Grover Beach, Pismo Beach, and to the Community Service Districts of Oceano and Avila Beach. In this study, a water balance and sediment yield analysis model was developed for the reservoir’s watershed. The model was used to estimate evaporation from the lake and to examine the effects of a wildfire on the reservoir. Evaporation and wildfire are dependent on variables that change on a spatial and temporal scale, making modeling challenging. The County of San Luis Obispo uses pan coefficients to estimate evapotranspiration losses …

Pressure Driven Desalination Utilizing Nanomaterials, Fangyou Xie

Master's Theses

Nanomaterials such as graphene oxide and carbon nanotubes, have demonstrated excellent properties for membrane desalination, including decrease of maintenance, increase of flux rate, simple solution casting, and impressive chemical inertness. Here, two projects are studied to investigate nanocarbon based membrane desalination. The first project is to prepare hybrid membranes with amyloid fibrils intercalated with graphene oxide sheets. The addition of protein amyloid fibrils expands the interlayer spacing between graphene oxide nanosheets and introduces additional functional groups in the diffusion pathways, resulting in increase of flux rate and rejection rate for the organic dyes. Amyloid fibrils also provide structural assistance to …

Rheological Studies Of Fully-Formulated Coatings Thickened With Heur: Effects Of Surfactants, Brandon M. Bonilla

Master's Theses

Rheology modifiers such as hydrophobically-modified ethoxylated urethane (HEUR)thickeners are included in waterborne latex coatings to optimize shear-rate dependent viscosity and other rheological properties. While these HEUR polymers are commonly used in industry, the complex chemical interactions that contribute to rheological properties are still not completely understood. Prior work in this area has focused on understanding latex-HEUR and latex-surfactant-HEUR interactions that affect rheological properties. Additionally, studies have been previously conducted to understand the relaxation mechanisms of complex interactions present in HEUR-thickened waterborne latex coatings under various dynamic conditions. The objective of this work is to extend the experimental work to fully-formulated …

An Investigation Of Antenna, Ligand Side-Chain, And Metal Ion Effects On The Optical And Mri Properties Of Bimodal Lanthanide (Iii) Complexes, Marisa Poveda

Master's Theses

Magnetic Resonance Imaging (MRI) is a leading anatomical imaging modality for disease diagnosis. With the aid of Gd³⁺ based contrast agents, high resolution images of biological structures can be obtained. However, there is an increased need for contrast agents that are responsive to specific analytes and chemical environments. Paramagnetic Chemical Exchange Saturation Transfer (PARACEST) agents that utilize a paramagnetic lanthanide ion chelated with a ligand have shown great promise in this area. Lanthanide ions also possess luminescence properties that do not suffer from common limitations of conventional optical imaging agents such as autofluorescence and photobleaching. The projects described in …

Human Intention Inference Using Fusion Of Gaze And Motion Information, Daniel Trombetta

Master's Theses

Enabling robots with the ability to quickly and accurately determine the intention of their human counterparts is a very important problem in Human-Robot Collaboration (HRC). The focus of this work is to provide a framework wherein multiple modalities of information, available to the robot through different sensors, are fused to estimate a human's action intent. In this thesis, two human intention estimation schemes are presented. In both cases, human intention is defined as a motion profile associated with a single goal location. The first scheme presents the first human intention estimator to fuse information from pupil tracking data as well …

Electrostatic Denaturation Of Dna-Cisplatin Adducts, Eddie Madrigal

Master's Theses

In this thesis, electrochemical approaches are used to determine the properties of deoxyribonucleic acid (DNA) by electrostatic denaturation. The electrochemical routine involves an application of a destabilization potential, an equilibration potential, and a square wave voltammogram (SWV) to monitor the extent of melting. Our method uses a monolayer consisting of thiol modified DNA and mercaptohexanol on a gold electrode. These electrodes are then incubated in a complementary sequence tagged with methylene blue. By using our electrostatic denaturation technique, different parameters are explored, such as surface densities, surface coverages, and ionic strengths. As proof of concept, these techniques were applied toward …

Determinants Of The Carbon Footprint Of German Swimmers 2020., Ann-Marie Muehlbauer

Master's Theses

The current climate situation is placing our planet and future generations at risk, which demonstrates the urgency to combat climate change and conduct research to support this effort. Calculating the carbon footprint of active sport participation represents an important opportunity to conduct additional research. This study examined the environmental attitudes and practices of swim club members in Germany. The study had three goals: First, to calculate the total and partial carbon footprint of German swimmers; second, to understand how sport organizations induce participants to engage in pro-environmental behavior; and third, to analyze various factors associated with carbon footprint, such as …

Additive Manufacturing Of Binary Alloy A Phase Field Approach, Manoj Ghosh

Master's Theses

A phase-field approach is pursued to study the solidification of binary alloys, and equations governing the kinetics of the phase transformation are derived. The Ginzburg Landau equation and Cahn Hilliard equation were developed for the binary alloy phasefield model, considering both free energy minimization and conservation of mass. The analytical solutions for a dilute solution alloy are derived. For the thin interface limit, the correlation between the phase-field mobility and kinetic interface coefficient is developed, neglecting the diffusivity at the solid side. For a one-dimensional steady-state condition, along with the diffuse interface, the concentration profile is established as a function …

The Megaprocessor As An Educational Tool Making The Abstract Concrete, Jonathon Beauregard Ii

Master's Theses

Computer architecture courses can be difficult for students to engage with and learn from. This is because, unlike most core courses for a computer science student, learning architecture is an abstract process. To address this, universities have implemented methods for teaching course material other than purely descriptive methods. This typically means using simulations to model some aspect of a CPU or FPGA (fieldprogrammable gate array) boards for hands-on experimentation in CPU design. However, there are issues with these tools. Simulations can only cover a few topics well, are prone to being abandoned, and introduce additional abstraction layers. FPGAs, while great …

Artificial Night Lighting And Anthropogenic Noise Alter Animal Activity, Body Condition, Species Richness, And Community Structure, Joshua Willems

Master's Theses

Sensory pollution from artificial night-lighting and anthropogenic noise have increased at a dramatic rate over the last several decades. Alterations to the sensory environment have been found to affect wildlife in a wide variety of ways including behavioral changes, physiological responses, changes in species interactions, and altered community structure. Increased levels of light and noise pollution can originate from many sources including roads, energy development and infrastructure, and urbanization. Even remote or protected areas are not immune to the effects of increased sensory disturbances with 63 percent of protected areas within the United States found to have been exposed to …

Freshwater Endmembers Impacting Carbonate Chemistry In The Mississippi Sound, Allison Savoie

Master's Theses

Coastal ecosystems are highly dynamic areas for carbon cycling and are likely to be negatively impacted by increasing ocean acidification. This research focused on dissolved inorganic carbon (DIC) and total alkalinity (TA) in the Mississippi Sound in order to understand the influence of local rivers that supply alkalinity to the area and buffer against ocean acidification. This area receives large fluxes of freshwater from local rivers, in addition to episodic inputs from the Mississippi River through a human-built diversion, the Bonnet Carré Spillway. Sites in the Mississippi Sound were sampled monthly during August 2018 to November 2019 and at weekly …

Non-Religious Employee's Perceptions Of Microaggressions And Their Relationship With Job Satisfaction As Moderated By Calling, Jessica Schultz

Master's Theses

The purpose of this study was to investigate the relationships between microaggressions, person-organization fit (P-O fit), job satisfaction, and calling in non-religious individuals. Established research demonstrates that job satisfaction is predicted by P-O fit (Dawis, 2005). Research with minority groups has found that microaggressions are negatively related to P-O fit and job satisfaction (Lyons, Velez, Mehta, & Neil, 2014). However, research has yet to examine these interactions with a non-religious population. Previous investigations have found that calling is positively correlated with both P-O fit and job satisfaction (Duffy & Dik, 2013; Duffy, Allan, & Dik, 2011; Hirschi, 2012), suggesting the …

An Adaptive Approach To Gibbs’ Phenomenon, Jannatul Ferdous Chhoa

Master's Theses

Gibbs’ Phenomenon, an unusual behavior of functions with sharp jumps, is encountered while applying the Fourier Transform on them. The resulting reconstructions have high frequency oscillations near the jumps making the reconstructions far from being accurate. To get rid of the unwanted oscillations, we used the Lanczos sigma factor to adjust the Fourier series and we came across three cases. Out of the three, two of them failed to give us the right reconstructions because either it was removing the oscillations partially but not entirely or it was completely removing them but smoothing out the jumps a little too much. …

The Effect Of Constant Relative Growth Rate Versus Constant Specific Growth Rate On Oocystis Sp, Rachel Kriner

Master's Theses

In this study, a strain of Oocystis sp. (S002) was grown using two different growth strategies at three different temperatures (15°C, 20°C, 25°C). One strategy (GS1) kept a constant specific growth rate (µ) and the other (GS2) kept a constant relative growth rate (µ/µ_max). In both strategies, the cultures were grown following the protocols of a hybrid growth system. The Dilution Phase is an initial semi-continuous growth phase that involves daily dilutions until set growth criteria are met. Followed by a batch culture growth protocol where the cultures were diluted at the onset of the first day and …

Exploring The Relationships Between Mothers' Use Of Food To Soothe, Feeding Type And Mode, Maternal Feeding Style, Infant Behavior, And Infant Weight-Related Outcomes During Early Infancy, Megan K. Hupp

Master's Theses

Rapid infant weight gain (RWG) in the first six months postpartum is a strong predictor for obesity during childhood and adolescence. Although biological factors can influence infant weight gain trajectories, the modifiable factor of parent feeding practices can also have an influence. The use of food to soothe (FTS), or the act of feeding a child when he/she is upset for reasons other than hunger, has been associated with unhealthy eating behaviors and less-favorable weight outcomes in children and older infants. However, limited studies have explored the use of FTS during early infancy before the introduction of solids foods. The …

Hydraulic Effects Of Perpendicular Water Approach Velocity On Meter Gate Flow Measurement, John M. Thorburn

Master's Theses

Accurate flow measurement is required to effectively manage water resources. California Senate Bill X7-7 (SB X7-7), legislates this need by requiring agricultural water providers serving areas greater than 25,000 acres to develop an Agricultural Water Management Plan (AWMP) and adopt pricing based at least partly on volumetric water deliveries (DWR, 2009). This study focused on two of the most common flow measurement/flow control devices used in California open channel water conveyance systems: the circular meter gate and the rectangular meter gate. Testing was conducted on three Armco-type (round gates over round discharge pipe) gates measuring 12”, 18”, and 24” and …

Antibacterial Coatings Derived From Novel Chemically Responsive Vesicles, Emily B. Mobley

Master's Theses

In order for a drug, or any material used for the purpose of eliciting a change in an organisms’ physical or chemical state, to be effective it must reach the intended target intact and for a sustained rate over time. Drug delivery systems encapsulate a drug to protect it from degradation, prevent side reactions, increase solubility, improve accumulation rates at target sites, and release drugs at a controlled rate. Controlled and sustained release of drugs is achieved by degradation of the carrier triggered by breaking dynamic chemical bonds caused by changes in the chemical environment such as pH or redox …

Quantifying The Ecological Drivers And Impacts Of Parrotfish Predation On Caribbean Corals Communities, Hannah Sima Rempel

Master's Theses

Parrotfishes (Scarinae) are dominant Caribbean herbivores that play an important role in reducing coral-algae competition by grazing algae; yet some species are also occasional coral predators (corallivores) and thereby can have direct negative impacts on coral growth and survivorship. There is concern that parrotfish corallivory may contribute to substantial long-term declines in targeted coral species, particularly in areas with a high biomass of parrotfishes and low cover of corals. However, the capacity of target coral species to heal from parrotfish predation and the ecological drivers of corallivory are poorly understood.

In Chapter 1, we examined the patterns of coral healing …

Fast Asymptotic Algorithm For Real-Time Analysis Of Multivariate Systems And Signals By Directed Transfer Function And Partial Directed Coherence Measures Of Connectivity, Farnaz Rezaei

Master's Theses

Connectivity Granger-causality measures in the frequency domain, such as the Directed Transfer Function (DTF) and Partial Directed Coherence (PDC) and their variants, constitute a family 𝜙 of measures that stem from the modeling of multidimensional time series by multivariate autoregressive (MVAR) models. 𝜙 measures have become popular for evaluation of causal interactions in neuronal networks. Surrogate and asymptotic statistical analysis are the two most frequently used methods to quantify the statistical significance of the derived interactions, a critical step for validation of the results. Each method has its own pros and cons, with the recently published asymptotic methodology being faster. …

An Application Of The Unscented Kalman Filter For Spacecraft Attitude Estimation On Real And Simulated Light Curve Data, Kent A. Rush

Master's Theses

In the past, analyses of lightcurve data have been applied to asteroids in order to determine their axis of rotation, rotation rate and other parameters. In recent decades, these analyses have begun to be applied in the domain of Earth orbiting spacecraft. Due to the complex geometry of spacecraft and the wide variety of parameters that can influence the way in which they reflect light, these analyses require more complex assumptions and a greater knowledge about the object being studied. Previous investigations have shown success in extracting attitude parameters from unresolved spacecraft using simulated data. This paper presents a focused …

Limitations Of Initial Orbit Determination Methods For Low Earth Orbit Cubesats With Short Arc Orbital Passes, James P. Johnson

Master's Theses

This thesis will focus on the performance of angles only initial orbit determi- nation (IOD) methods on observational data of low Earth orbit (LEO) CubeSats. Using data obtained by Lockheed Martin’s Space Object Tracking (SpOT) facil- ity, four methods: Gauss, Double-R, Gooding and Assumed Circular, will use different amounts of orbital arc to determine which methods perform the best in the short arc regime of less than 10 degrees of orbital arc. Once the best method for estimating the orbit is determined, there will be analysis on whether these IOD methods are accurate enough to predict a secondary observation session. …

Combining Machine Learning And Empirical Engineering Methods Towards Improving Oil Production Forecasting, Andrew J. Allen

Master's Theses

Current methods of production forecasting such as decline curve analysis (DCA) or numerical simulation require years of historical production data, and their accuracy is limited by the choice of model parameters. Unconventional resources have proven challenging to apply traditional methods of production forecasting because they lack long production histories and have extremely variable model parameters. This research proposes a data-driven alternative to reservoir simulation and production forecasting techniques. We create a proxy-well model for predicting cumulative oil production by selecting statistically significant well completion parameters and reservoir information as independent predictor variables in regression-based models. Then, principal component analysis (PCA) …