Physical Sciences and Mathematics Commons^™

Analyzing The Impacts Of Beaver Dam And Beaver Dam Analog Complexes To Stream Ecology Within The Intermountain West, J. Marshall Wolf

All Graduate Theses and Dissertations, Fall 2023 to Present

Streams, rivers, and their floodplains throughout the world are impaired due to human modifications. Recent research has demonstrated that restoration projects prioritizing the proper functioning of ecosystems have better restoration outcomes than projects which focus on restoring form alone. Throughout North America, beaver-mediated restoration is becoming a leading method for improving the functioning of stream ecosystems that are in a degraded state. In areas where beaver are absent or the habitat is too degraded to currently permit their dam building, man-made beaver dam analogs (BDAs) are being used to restore stream habitat with an eye to future beaver recolonization. However, …

An Ensemble Approach For Mapping Snow Water Equivalent In Utah, Logan Schneider

All Graduate Theses and Dissertations, Fall 2023 to Present

Mountain snowpack is an important resource for water management planning in Utah. Snow water equivalent (SWE) is the amount of water contained in a snowpack. A few organizations predict SWE throughout the United States but struggle making accurate predictions in mountainous regions. Weather stations provide accurate measurements of SWE but have limited spatial coverage that hinders the ability to make accurate estimates statewide. This thesis examines the accuracy of current models and proposes using local weather measurements to improve upon national level predictions. An R statistical software package named rsnodas implements this process while allowing the public access to a …

Multi-Objective Water Management In Idaho's Henrys Fork Watershed: Leveraging Reservoir Operation And Groundwater Pathways To Benefit Aquatic Habitat, Christina N. Morrisett

All Graduate Theses and Dissertations, Fall 2023 to Present

Multi-user water management is a challenging arena further complicated by climate change. This research is based in the Henrys Fork, Snake River, Idaho—an agricultural watershed that exemplifies those throughout the semi-arid American West. This dissertation uses an integrated approach that considers groundwater-river relationships, farm-scale decisions and basin-scale outcomes, upstream reservoir operation for downstream aquatic habitat, water rights, and collaborative stakeholder management to identify drought adaptation strategies accordingly.

Chapter 2 uses an interdisciplinary approach to quantify how improvements to irrigation efficiency at the farm-scale (i.e., converting from flood to sprinkler irrigation) can add up to affect hydrology at the landscape-scale and …

Synthesis And Characterization Of Colorimetric And Flurometric Chemosensor For Trivalent Metal Ions, Fazila Haque

Honors Program Theses and Research Projects

There are many biological and environmental uses for trivalent metals (like Fe3+, Al3+, and Cr3+) within our daily lives. Whether these trivalent metals are found in deficiency or excess can cause issues within our environment (global warming) or our bodies (can cause problems with our digestive, cardiovascular, and immune systems). Being able to detect them and understanding their importance becomes crucial in our understanding of the world that surrounds us.
One of the ways we can detect these trivalent metals is through the use of chemosensors. Chemosensors are used to sense analyte (trivalent metal) to produce a signal (fluorescence or …

Discourses Across Periods Of Time, Amanda Raquel Moreno

Theses

This literature review explores the revolutionary effect of generative artificial intelligence (AI) and virtual reality (VR) on digital art history, specifically concentrating on their capacity to enable dialogical exchanges with historical figures and deepen the understanding of artworks. This study considers the current state of research, detecting key methodologies, areas of improvement, and possible challenges and ethical concerns. The example historical figure used in this analysis is the iconic Mexican artist Frida Kahlo. Kahlo’s refusal to correspond to a specific artistic style makes her an ideal subject for generative AI and VR-based investigation, offering fresh insights into her work. The …

Influence Of Pavement Conditions On Commercial Motor Vehicle Crashes, Stephen Arhin, Babin Manandhar, Adam Gatiba

Mineta Transportation Institute

Commercial motor vehicle (CMV) safety is a major concern in the United States, including the District of Columbia (DC), where CMVs make up 15% of traffic. This research uses a comprehensive approach, combining statistical analysis and machine learning techniques, to investigate the impact of road pavement conditions on CMV accidents. The study integrates traffic crash data from the Traffic Accident Reporting and Analysis Systems Version 2.0 (TARAS2) database with pavement condition data provided by the District Department of Transportation (DDOT). Data spanning from 2016 to 2020 was collected and analyzed, focusing on CMV routes in DC. The analysis employs binary …

Global Dataset Of Soil Organic Carbon In Tidal Marshes, Tania L. Maxwell, André S. Rovai, Maria F. Adame, Janine B. Adams, José Álvarez-Rogel, William E. N. Austin, Kim Beasy, Francesco Boscutti, Michael E. Böttcher, Tjeerd J. Bouma, Richard H. Bulmer, Annette Burden, Shannon A. Burke, Saritta Camacho, Doongar R. Chaudhary, Gail L. Chmura, Margareth Copertino, Grace M. Cott, Christopher Craft, John Day, Carmen B. De Los Santos, Lionel Denis, Weixin Ding, Joanna C. Ellison, Carolyn J. E. Lewis, Luise Giani, Maria Gispert, Swanne Gontharet, José A. González-Pérez, M. Nazaret González-Alcaraz, Connor Gorham, Anna E. L. Graversen, Anthony Grey, Roberta Guerra, Qiang He, James R. Holmquist, Alice R. Jones, José A. Juanes, Brian P. Kelleher, Karen E. Kohfeld, Dorte Krause-Jensen, Anna Lafratta, Paul S. Lavery, Edward A. Laws, Carmen Leiva-Dueñas, Pei S. Loh, Catherine E. Lovelock, Carolyn J. Lundquist, Peter I. Macreadie, Inés Mazarrasa, J. Patrick Megonigal, Joao M. Neto, Juliana Nogueira, Michael J. Osland, Jordi F. Pagès, Nipuni Perera, Eva-Maria Pfeiffer, Thomas Pollmann, Jacqueline L. Raw, María Recio, Ana C. Ruiz-Fernández, Sophie K. Russell, John M. Rybczyk, Marek Sammul, Christian Sanders, Rui Santos, Oscar Serrano, Matthias Siewert, Craig Smeaton, Zhaoliang Song, Carmen Trasar-Cepeda, Robert R. Twilley, Marijn Van De Broek, Stefano Vitti, Livia V. Antisari, Baptiste Voltz, Christy N. Wails, Raymond D. Ward, Melissa Ward, Jaxine Wolfe, Renmin Yang, Sebastian Zubrzycki, Emily Landis, Lindsey Smart, Mark Spalding, Thomas A. Worthington

Research outputs 2022 to 2026

Tidal marshes store large amounts of organic carbon in their soils. Field data quantifying soil organic carbon (SOC) stocks provide an important resource for researchers, natural resource managers, and policy-makers working towards the protection, restoration, and valuation of these ecosystems. We collated a global dataset of tidal marsh soil organic carbon (MarSOC) from 99 studies that includes location, soil depth, site name, dry bulk density, SOC, and/or soil organic matter (SOM). The MarSOC dataset includes 17,454 data points from 2,329 unique locations, and 29 countries. We generated a general transfer function for the conversion of SOM to SOC. Using this …

Gut Microbial Communities Of Hybridising Pygmy Angelfishes Reflect Species Boundaries, Megan J. Huggett, Jean-Paul A. Hobbs, Federico Vitelli, Michael Stat, Tane H. Sinclair-Taylor, Michael Bunce, Joseph D. Dibattista

Research outputs 2022 to 2026

Hybridisation and introgression of eukaryotic genomes can generate new species or subsume existing ones, with direct and indirect consequences for biodiversity. An understudied component of these evolutionary forces is their potentially rapid effect on host gut microbiomes, and whether these pliable microcosms may serve as early biological indicators of speciation. We address this hypothesis in a field study of angelfishes (genus Centropyge), which have one of the highest prevalence of hybridisation within coral reef fish. In our study region of the Eastern Indian Ocean, the parent fish species and their hybrids cohabit and display no differences in their diet, behaviour, …

Investigating A Passive Treatment System For The Removal Of Nutrients From Urban Runoff, Jasminn Gray

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Environmental Protection Agency recognizes urban runoff as a major contributor of surface water pollution with nutrients as the second largest cause of surface water impairment in the United States. While a water quality standard of 100 lbs/day total phosphorus load allocation for all nonpoint sources is permitted for the Las Vegas Valley (LVV) under the National Pollutant Discharge Elimination System, currently there is not a counterpart standard for nitrogen. With the continued development of the LVV and the depletion of the quantity of water in Lake Mead due to the ongoing drought, the concentrations of phosphorus and nitrogen species …

Observational Uncertainty For Global Drought-Pluvial Volatility, Yichan Li, Linyin Cheng, Chiyuan Miao, Zhiyong Liu

Geosciences Faculty Publications and Presentations

Droughts and pluvials have occurred in most regions in the past. However, what calls growing attention is the additive effects of these two opposite extreme events occurring in spatial-temporal proximity to one another, sometimes beyond either of the hazards individually. This study examines the likelihood of global drought-pluvial volatility which involves both meteorological drought-to-pluvial (DTP) and pluvial-to-meteorological drought transitions; meanwhile, identifies discrepancies and agreements among the widely used observations for such events, an aspect that remains currently overlooked. Globally, we find that the observation-based data sets including Global Precipitation Climatology Center (GPCC), Climate Research Unit (CRU) and ERA5 reach a …

Uncertainty In Streamflow Measurements Significantly Impacts Estimates Of Downstream Nitrate Export, Shannon L. Speir, C. Nathan Jones, Arial J. Shogren, Carla L. Atkinson

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Across watershed science, two key variables emerge–streamflow and solute concentration–which serve as the basis for efforts ranging from basic watershed biogeochemistry research to policy decisions surrounding watershed management. However, we rarely account for how error in discharge (Q) impacts estimates of downstream nutrient loading. Here, we examined the impact of uncertainty in streamflow measurements on estimates of downstream nitrate export using publicly available data from the U.S. Geological Survey (USGS). We characterized how uncertainty in stage-discharge relationships impacts annual flux estimates across 70 USGS gages. Our results indicate the interquartile range of relative error in Q was 33% across these …

Substantial Blue Carbon Sequestration In The World’S Largest Seagrass Meadow, Chuancheng Fu, Sofia Frappi, Michelle N. Havlik, Wells Howe, S. David Harris, Elisa Laiolo, Austin J. Gallagher, Pere Masqué, Carlos M. Duarte

Research outputs 2022 to 2026

Seagrass meadows are important sinks for organic carbon and provide co-benefits. However, data on the organic carbon stock in seagrass sediments are scarce for many regions, particularly The Bahamas, which accounts for up to 40.7% of the documented global seagrass area, limiting formulation of blue carbon strategies. Here, we sampled 10 seagrass meadows across an extensive island chain in The Bahamas. We estimate that Bahamas seagrass meadows store 0.42–0.59 Pg organic carbon in the top-meter sediments with an accumulation rate of 2.1–2.9 Tg annually, representing a substantial global blue carbon hotspot. Autochthonous organic carbon in sediments decreased from ~1980 onwards, …

Multi-Scale Mapping Of Australia’S Terrestrial And Blue Carbon Stocks And Their Continental And Bioregional Drivers, Lewis Walden, Oscar Serrano, Mingxi Zhang, Zefang Shen, James Z. Sippo, Lauren T. Bennett, Damien T. Maher, Catherine E. Lovelock, Peter I. Macreadie, Connor Gorham, Anna Lafratta, Paul S. Lavery, Luke Mosley, Gloria M. S. Reithmaier, Jeffrey J. Kelleway, Sabine Dittmann, Fernanda Adame, Carlos M. Duarte, John B. Gallagher, Pawel Waryszak, Paul Carnell, Sabine Kasel, Nina Hinko-Najera, Rakib Hassan, Madeline Goddard, Alice R. Jones, Raphael A. Viscarra Rossel

Research outputs 2022 to 2026

The soil in terrestrial and coastal blue carbon ecosystems is an important carbon sink. National carbon inventories require accurate assessments of soil carbon in these ecosystems to aid conservation, preservation, and nature-based climate change mitigation strategies. Here we harmonise measurements from Australia’s terrestrial and blue carbon ecosystems and apply multi-scale machine learning to derive spatially explicit estimates of soil carbon stocks and the environmental drivers of variation. We find that climate and vegetation are the primary drivers of variation at the continental scale, while ecosystem type, terrain, clay content, mineralogy and nutrients drive subregional variations. We estimate that in the …

The Construction Of Khovanov Homology, Shiaohan Liu

Master's Theses

Knot theory is a rich topic in topology that studies the how circles can be embedded in Euclidean 3-space. One of the main questions in knot theory is how to distinguish between different types of knots efficiently. One way to approach this problem is to study knot invariants, which are properties of knots that do not change under a standard set of deformations. We give a brief overview of basic knot theory, and examine a specific knot invariant known as Khovanov homology. Khovanov homology is a homological invariant that refines the Jones polynomial, another knot invariant that assigns a Laurent …

Complex Dimensions Of 100 Different Sierpinski Carpet Modifications, Gregory Parker Leathrum

Master's Theses

We used Dr. M. L. Lapidus's Fractal Zeta Functions to analyze the complex fractal dimensions of 100 different modifications of the Sierpinski Carpet fractal construction. We will showcase the theorems that made calculations easier, as well as Desmos tools that helped in classifying the different fractals and computing their complex dimensions. We will also showcase all 100 of the Sierpinski Carpet modifications and their complex dimensions.

Nanoparticles And The Environment: Biopolymer Grafted Cellulose And Screen-Printed Carbon Nanotube Composites, Dominique Henry Porcincula

Master's Theses

A host of environmental issues will define the state of the environment in the 21^st century, with plastic pollution and water shortages among them. While solutions to these problems require large-scale, multipronged solutions, one way we can address them is through material innovation and the use of nanoparticles.

In the first project, we address the issue of plastic pollution by creating nanocomposites of biodegradable polymers (PLA and PCL) with cellulose nanofibrils. Here, PLA and PCL are grafted from the surface of cellulose nanofibrils via ring-opening polymerization of cyclic ester monomers. Polymer-grafted cellulose (PGC) is characterized with structural analysis, solubility …

Wabanaki Experiences And Perspectives On “Our Shared Ocean”: Maine Indian Tribal-State Commission Special Report Sea Run, Anthony W. Sutton, Judson Esty-Kendall, Paul Thibeault

Maine Policy Review

The Maine Indian State Tribal Commission (MITSC) recently published a special report titled, Sea Run, documenting the impact of Colonial and Maine policies and activities on the quality and quantity of tribal fisheries spanning the time from first contact between Europeans and the Wabanaki Nations to today.

The Surprising Oceanography Of The Gulf Of Maine, Nicholas R. Record, Benjamin Tupper, Johnathan Evanilla, Kyle Oliveira, Camille Ross, Logan Ngai, Karen Stamieszkin

Maine Policy Review

The oceanography of the Gulf of Maine has changed in ways that have not been seen previously but that are likely to be more common in the future–changes like extreme rapid warming and declines in primary productivity. The changing oceanography has underpinned surprising losses in commercial stocks and endangered species. Because of the rapid rate of change, some have viewed the Gulf of Maine as a window into the ocean’s future, with the idea that lessons learned can be applied in places that have yet to experience similar rapid changes. We can examine the dynamics, origin, and implications of surprising …

The Changing Tides Of Action To Address Ocean Acidification In Maine, Ivy L. Frignoca, Heather R. Kenyon

Maine Policy Review

As carbon dioxide emissions continue to rise worldwide, ocean acidification has become a consequence that threatens both human and natural processes. On a global scale, ocean acidification is relatively well understood. However, the complex ecosystem of the nearshore environment presents challenges for monitoring and addressing ocean acidification. In a state such as Maine, whose communities heavily depend on the health of the coastal environment, understanding this threat becomes critically important.

In 2014, Maine’s legislature established a six month study commission to investigate this problem and produce recommendations. The commission proposed a coast-wide monitoring network that could identify and use a …

New Office Supports Maine Climate Action, Parker Gassett, Ivan Fernandez

Maine Policy Review

Expanding and expediting access to climate change information can improve collective action outcomes. Accordingly, the Maine Climate Action Plan called for the creation of an information-coordinating hub, to enable effective and efficient use of climate information in Maine’s climate change response. To aid that need, the University of Maine created the Maine Climate Science Information Exchange (MCSIE) office as a gateway to information about climate-relevant research, the scientists conducting that research, and the most recent data and applied science efforts relating to Maine’s climate change strategies. The office was established in 2023, after a year of developing prototypes of the …

Including The Human Dimension Into Resilience Planning For Maine’S Lobster Fishery, Katherine Maltby, Katherine E. Mills

Maine Policy Review

The American lobster fishery is one of the most valuable in the US but is being affected by climate-driven shifts in lobster availability, impacting people’s ability to harvest the resource and sparking broader adaptation challenges. Since the late 1990s, lobster landings in the Gulf of Maine (GOM) have climbed to record levels while those in Southern New England (SNE) have experienced significant declines. The experiences of SNE lobstermen during these declines can offer important lessons for both individual lobstermen and communities in the GOM, where lobster abundance is currently at high levels but facing future uncertainty given continuing climate trends. …

Province-Wide Tapping Of A Shallow, Variably Depleted, And Metasomatized Mantle To Generate Earliest Flood Basalt Magmas Of The Columbia River Basalt, Northwestern Usa, Martin J. Streck, Luke James Fredenberg, Lena M. Fox, Emily B. Cahoon, Mary J. Mass

Geology Faculty Publications and Presentations

The Miocene Columbia River Basalt Group (CRBG) of the Pacific Northwest of the United States is the world’s youngest and smallest large igneous province. Its earliest formations are the Imnaha, Steens, and now the Picture Gorge Basalt (PGB), and they were sourced from three different dike swarms exposed from SE Washington to Nevada to northcentral Oregon. PGB is often viewed to be distinct from the other formations, as its magmas are sourced from a shallow, relatively depleted, and later subduction-induced metasomatized mantle, along with its young stratigraphic position. It has long been known that the lowermost American Bar flows (AB1&2) …

Foundations Of Memory Capacity In Models Of Neural Cognition, Chandradeep Chowdhury

Master's Theses

A central problem in neuroscience is to understand how memories are formed as a result of the activities of neurons. Valiant’s neuroidal model attempted to address this question by modeling the brain as a random graph and memories as subgraphs within that graph. However the question of memory capacity within that model has not been explored: how many memories can the brain hold? Valiant introduced the concept of interference between memories as the defining factor for capacity; excessive interference signals the model has reached capacity. Since then, exploration of capacity has been limited, but recent investigations have delved into the …

The Tidal Prism, Viable Eelgrass Habitat, And The Effects Of Sea Level Rise In Morro Bay, Kaden A. Caliendo

Master's Theses

The tidal prism, or the volume of water exchanged from the sea to an estuary from mean low to mean high tide, influences system hydrodynamics and ecological functioning. Since 1884, the tidal prism in Morro Bay, California has been estimated to be decreasing over time due to sedimentation from upstream practices. What is the current tidal prism in Morro Bay and how will that change with sea level rise? How will eelgrass respond to rising sea levels?

For this study, inexpensive tidal gauges were deployed at four locations in Morro Bay from March to August 2023 to measure spatially varying …

The Relationship Between Biofouling Adhesion And Frequency Of Mechanical Cleaning To Control The Recruitment To Clear Coatings, Dylan Thomas Eggers

Theses and Dissertations

There is a need to control biofouling on sensors and transparent windows in the marine environment. Clear silicone coatings offer a method to reduce the adhesion strength of marine organisms to the surface, however, these also require mechanical cleaning to maintain the surfaces free of fouling. This research evaluated the performance of eighty seven formulations and took the top two candidates to investigate a) the frequencies of wiping required by a brush to maintain two coatings and uncoated glass surfaces free of fouling and b) the effects of clear silicone coatings fouling release properties on required frequencies. The panels were …

Analyzing The Effects Of Ultrafast Laser Processing On Mechanical Properties Of 3d-Printed Pla Parts, Darshan Pramodbhai Yadav

Theses and Dissertations

Recent advances in additive manufacturing technologies have already led to wide-scale adoption of 3D-printed parts in various industries. The expansion in choice of materials that can be processed, particularly using Fused Deposition Modeling (FDM), and the steady advancements in dimensional accuracy control have extended the range of applications far beyond rapid prototyping. However, additive manufacturing still has considerable limitations compared to traditional and subtractive manufacturing processes. This work addresses limitations associated with the as-deposited surface roughness of 3D-printed parts. The effects of roughness-induced stress concentrations were studied on ultimate tensile strength and fatigue life. The samples were manufactured using a …

Low Reynolds Number Locomotion Near Interfaces In Two-Fluid Media, Avriel Rowena Mae Cartwright

Theses and Dissertations

Microorganisms often swim within complex fluid environments composed of multiple materials with very different properties. Biological locomotion, including swimming speed, is significantly impacted by the physical composition and rheology of the surrounding fluid environment, as well as the presence of phase boundaries and free interfaces, across which physical properties of the fluid media may vary greatly. Through computational simulations, we first investigate the classical Taylor’s swimming sheet problem near interfaces within multi-fluid environments using a two-fluid immersed boundary method. The accuracy of the methodology is illustrated through comparisons with analytical solutions. Our simulation results indicate that the interface dynamics and …

Accelerating Machine Learning Inference For Satellite Component Feature Extraction Using Fpgas., Andrew Ekblad

Theses and Dissertations

Running computer vision algorithms requires complex devices with lots of computing power, these types of devices are not well suited for space deployment. The harsh radiation environment and limited power budgets have hindered the ability of running advanced computer vision algorithms in space. This problem makes running an on-orbit servicing detection algorithm very difficult. This work proposes using a low powered FPGA to accelerate the computer vision algorithms that enable satellite component feature extraction. This work uses AMD/Xilinx’s Zynq SoC and DPU IP to run model inference. Experiments in this work centered around improving model post processing by creating implementations …

Anxiety In International Graduate Students With U.S. Education, Aeshah Zarraa

Theses and Dissertations

Anxiety in international graduate students is a significant concern for most students planning to move out of their home country to pursue higher education in the United States. The primary purpose of this research is to identify the prime causes of anxiety triggers in the targetted Graduate students, thereby determining a step-wise methodology development to address the causes. The study initially identified a set of graduate students who were voluntarily willing to collaborate and address their concerns anonymously to identify the significant issues faced by current students and alumni of the Florida Institute of Technology, Melbourne, Florida. Several questions were …

A Bio-Tribocorrosion Comparison Between Additively Manufactured And Forged Ti6al4v Parts, Sina Matin, Sahar Toorandaz, Saman Nikpour, Hamidreza Abdolvand, Eshan Toyserkani, Yolanda S. Hedberg

Chemistry Publications

Ti6Al4V has been used widely as a biomedical alloy and is increasingly manufactured by additive manufacturing due to customized shapes. As implant material, it is frequently exposed to both friction and corrosive environments. This study investigates the effect of the fabrication process (laser powder bed fusion and forging) on the tribocorrosion behavior of Ti6Al4V in various environments including diluted hydrochloric acid to simulate the acidic environment in a crevice (HCl), phosphate-buffered saline (pH 7.3) with 10 g/L bovine serum albumin (PBS+BSA), and PBS+BSA with 30 mM H2O2. While the presence of BSA hindered the repassivation (reforming of the protective passive …