Physical Sciences and Mathematics Commons^™

A Multi-Tiered Assessment Of Primary Production In Great Salt Lake, Soren Brothers, Melissa Cobo, R. Douglas Ramsey, Wayne A. Wurtsbaugh, Erin N. Rivers

Watershed Sciences Faculty Publications

Great Salt Lake (GSL) is the largest saline lake in the western hemisphere. Despite this, relatively little is known regarding ecological functioning within the lake, including detailed assessments of rates of primary productivity and ecosystem productivity. Analyses of primary production in GSL are complicated by the high heterogeneity of the system, including a broad salinity gradient from near-fresh conditions at the river confluences in Farmington and Bear River Bays to the hyper-saline conditions of the lake’s northwest arm (Gunnison Bay). Further complicating estimates of primary productivity is the possibility of high rates of benthic primary production (by benthic algae and …

Drivers Of Variability In Blue Carbon Stocks And Burial Rates Across European Estuarine Habitats, Inés Mazarrasa, Joao M. Neto, Tjeerd J. Bouma, Tim Grandjean, Jordi Garcia-Orellana, Pere Masqué, María Recio, Óscar Serrano, Araceli Puente, José A. Juanes

Research outputs 2022 to 2026

The implementation of climate change mitigation strategies based on the conservation and restoration of Blue Carbon ecosystems requires a deep understanding of the magnitude and variability in organic carbon (Corg) storage across and within these ecosystems. This study explored the variability in soil Corg stocks and burial rates across and within intertidal estuarine habitats of the Atlantic European coast and its relation to biotic and abiotic drivers. A total of 136 soil cores were collected across saltmarshes located at different tidal zones (high marsh, N = 45; low marsh, N = 30), seagrass meadows (N = 17) and tidal flats …

Season, Not Long-Term Warming, Affects The Relationship Between Ecosystem Function And Microbial Diversity, Melissa S. Shinfuku, Luiz A. Domeignoz-Horta, Mallory J. Choudoir, Serita D. Frey, Kristen M. Deangelis

Faculty Publications

Across biomes, soil biodiversity promotes ecosystem functions. However, whether this relationship will be maintained under climate change is uncertain. Here, using two long-term warming experiments, we investigated how warming affects the relationship between ecosystem functions and microbial diversity across seasons, soil horizons, and warming duration. The soils in these warming experiments were heated +5 °C above ambient for 13 or 28 years. We measured seven different ecosystem functions representative of soil carbon cycling, soil nitrogen cycling, or nutrient pools. We also surveyed bacterial and fungal community diversity. We found that the relationship between ecosystem function and bacterial diversity and the …

Approved Butte Reduction Works (Brw) Smelter Area Mine Waste Remediation And Contaminated Groundwater Hydraulic Control Site Quality Assurance Project Plan (Qapp) For Microbial Analysis And Biotreatability; Request For Change Brw-2023-02, Josh Bryson

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Approval For Draft Final 2022 Annual Monitoring Report For The Rocker Timber Framing And Treating Plant Operable Unit; Dated April 6, 2023, Nikia Greene

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Due Tomorrow, Do Tomorrow: Measuring And Reducing Procrastination Behavior Among Introductory Physics Students In An Online Environment, Zachary Felker

Electronic Theses and Dissertations, 2020-2023

This work is focused on the measurement and prevention of procrastination behavior among college level introductory physics students completing online assignments in the form of mastery-based online learning modules. The research is conducted in two studies. The first study evaluates the effectiveness of offering students the opportunity to earn a small amount of extra credit for completing portions of their homework early. Unsupervised machine learning is used to identify an optimum cutoff duration which differentiates taking a short break during a continuous study session from a long break between two different study sessions. Using this cutoff, the study shows that …

Efficient Convolutional Neural Networks For Image Classification And Regression, Muhammad Tayyab

Electronic Theses and Dissertations, 2020-2023

Neural networks have been a topic of research since 1970s and the Convolutional Neural Networks (CNNs) were first shown to work well for hand written digits recognition in 1998. These early networks were however still shallow and contained only a few layers. Moreover these networks were mostly trained on a small amount of data in contrast to the modern CNNs which contain hundreds of convolution layers and are trained on millions of images. However, this recent shift in machine learning comes at a cost. Modern neural networks have extremely large number of parameters and require huge amount of computations for …

Improved Endmember Mixing Analysis (Emma): Application To A Nested Catchment, Provo River, Northern Utah, Alyssa Nicole Thompson

Theses and Dissertations

An endmember mixing analysis (EMMA) is a hydrograph separation technique used to identify and quantify stream source contributions, but the error within the results of the analysis itself can be difficult to quantify. Employing EMMA to accurately quantify these contributions is particularly important for critical watersheds that supply water to large populations, such as montane watersheds. We applied EMMA to the Provo River, a nested catchment with three monitoring locations in northern Utah, to understand the limitations and potential improvements that could be made to EMMA. Four main endmembers (quartzite groundwater, soil water, snow and carbonate groundwater) were identified for …

A Study On Robustness And Semantic Understanding Of Visual Models, Madeline Chantry

Electronic Theses and Dissertations, 2020-2023

Vision models have improved in popularity and performance on many tasks since the emergence of large-scale datasets, improved access to computational resources, and new model architectures like the transformer. However, it is still not well understood if these models can be deployed in the real world. Because these models are "blackbox" architectures, we do not fully understand what these models are truly learning. An understanding of what models learn "underneath the hood" would result in better improvements for real-world scenarios. Motivated by this, we benchmark these impressive visual models using newly proposed datasets and tasks on their robustness and their …

Synthesis And Characterization Of The N-Succinyl-L,L-Diaminopimelic Acid Desuccinylase (Dape) Alternate Substrate Analog N,N-Dimethyl-L,L-Sdap, Zachary J. Liveris, Emma H. Kelley, Emma Simmons, Katherine Konczak, Marlon Lutz Jr., Miguel Ballicora, Ken W. Olsen, Daniel P. Becker Ph.D.

Chemistry: Faculty Publications and Other Works

Growing antibiotic resistance by pathogenic bacteria has led to a global crisis. The bacterial enzyme N-succinyl-l,l-diaminopimelic acid desuccinylase (DapE) provides a very attractive target for the discovery of a new class of antibiotics, as it resides exclusively in many pathogenic bacterial strains and is a key enzyme in the lysine biosynthetic pathway. This pathway is responsible for the production of lysine as well as meso-diaminopimelate (m-DAP), both of which are required for peptidoglycan cell-wall synthesis, and lysine for peptide synthesis. The enzyme DapE catalyzes the hydrolysis of N-succinyl-l,l-diaminopimelic acid (l,l-SDAP) to succinate and l,l-diaminopimelic …

Electron Beam Lithography And Dimensional Metrology For Fin And Nanowire Devices On Ge, Sige And Geoi Substrates, Nikolay Petkov, Margarita Georgieva, Sinan Bugu, Ray Duffy, Brendan Mccarthy, Maksym Myronov, Ann-Marie Kelleher, Graeme Maxwell, Giorgos Fagas

Physical Sciences Publications

Until now there is no systematic study on the effect of the substrate type on the hydrogen silsesquioxane (HSQ) electron beam lithography (EBL) patterning process. We investigate arrays of line structures with varying width and spacing, starting at 10 nm, exposed at varying dose, and developed by salty NaOH and TMAH developers on group IV semiconductor substrates. We demonstrate that the HSQ EBL process on Ge is much more limited in achieving the smallest obtainable features, having optimal uniformity and fidelity, in comparison to Si. Monte-Carlo simulations of the e-beam/substrate interactions for “pure” Si and Ge substrates, and varying content …

A Neural-Network-Based Landscape Search Engine: Lse Wisconsin, Matthew Haffner, Matthew Dewitte, Papia F. Rozario, Gustavo A. Ovando-Montejo

Environment and Society Faculty Publications

The task of image retrieval is common in the world of data science and deep learning, but it has received less attention in the field of remote sensing. The authors seek to fill this gap in research through the presentation of a web-based landscape search engine for the US state of Wisconsin. The application allows users to select a location on the map and to find similar locations based on terrain and vegetation characteristics. It utilizes three neural network models—VGG16, ResNet-50, and NasNet—on digital elevation model data, and uses the NDVI mean and standard deviation for comparing vegetation data. The …

Ocr Post-Processing Using Large Language Models, Mahdi Hajiali

UNLV Theses, Dissertations, Professional Papers, and Capstones

Optical Character Recognition (OCR) technology transforms textual visuals into an electronically readable, non-graphical format of the text. This allows the editing and other text manipulation of the content by language technology software such as machine translation, text comprehension, query-answering systems, and search engines. While Optical Character Recognition (OCR) systems continually progress towards greater precision, several complications persist when dealing with low-resolution source images or those with multicolored backgrounds. Consequently, the text derived from OCR necessitates additional refinement to optimize accuracy, beneficial for various subsequent applications. It is recognized that the character accuracy of OCR-generated text may influence certain natural language …

A Search For Chiral Asymmetry In Secondary Electron Emission From Cysteine Induced By Longitudinally Polarized Electrons, K. J. Ahrendsen, Kenneth Wayne Trantham, D. Tupa, T. J. Gay

Department of Physics and Astronomy: Faculty Publications

We performed experiments searching for chirality-dependent secondary electron emission for a 141 eV longitudinally spin-polarized electron beam incident on a thick solid cysteine target. We determined the secondary electron yield by measuring the positive current produced when the cysteine target was negatively biased. No spin-dependent effects to a level of 10⁻³ were found for the secondary electron emission yield.

Magnetic Nanodoping: Atomic Control Of Spin States In Cobalt Doped Silver Clusters, Vicente Zamudio-Bayer, Konstantin Hirsch, Lei Ma, Kobe De Knijf, X. S. Xu, Arkadiusz Ławicki, Akira Terasaki, Piero Ferrari, Bernd Von Issendorff, Peter Lievens, Walt A. De Heer, J. Tobias Lau, Ewald Janssens

Department of Physics and Astronomy: Faculty Publications

The interaction of magnetic dopants with delocalized electron states can result in interesting many-body physics. Here, the magnetic properties of neutral and charged finite silver metal host clusters with a magnetic cobalt atom impurity were investigated experimentally by exploiting the complementary methods of Stern- Gerlach molecular beam deflection and x-ray magnetic circular dichroism spectroscopy and are accompanied by density functional theory calculations and charge transfer multiplet simulations. The influence of the number of valence electrons and the consequences of impurity encapsulation were addressed in free size-selected, singly cobalt-doped silver clusters CoAg^0,_n+ (n = 2–15). Encapsulation of the …

Insar Time Series Analysis To Evaluate Subsidence Risk Of Monumental Chandigarh City (India) And Surroundings, Jungrack Kim, Shih-Yuan Lin, Tejpal Singh, Ramesh P. Singh

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Groundwater depletion is one of the serious geo-environmental issues causing ground subsidence, which damage buildings, infrastructures and causes loss of life. The quantitative and qualitative evaluation of groundwater variability requires multiple approaches to measure hydraulic head level and geodetic deformation. In this study, we have made efforts to integrate multiple hierarchical space-borne data, including Gravity Recovery and Climate Experiment (GRACE), Sentinel-1 Interferometric Synthetic Aperture Radar (InSAR), geological and hydrological data, to quantify subsidence in Chandigarh city and its surroundings. First, we conducted New-Small BAseline Subsets (NSBAS) and pointwise persistent scatterer (PS) InSAR techniques in parallel, using three-years Sentinel-1 data showing …

Applications Of Observational Seismology: Insights Into Volcanic And Near Surface Processes, Justin T. Wilgus

Earth and Planetary Sciences ETDs

The field of observational seismology has made tremendous progress in the past two decades. This progress has been multi-faceted in form, but significant contributions emanated from 1) increases in both the quality and the quantity of seismic data 2) advances in computational power 3) advances in algorithmic capability, including machine learning. In this dissertation I report on three distinctly different seismic applications made possible by the aforementioned progress and discuss the insights these applications have provided in understanding volcanic and near surface processes of the Earth.

In the first chapter titled, “Shear Velocity Evidence of Upper Crustal Magma Storage Beneath …

Draft Final 2023 Butte Priority Soils Operable Unit Helehan Borrow Submittal #1, Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

A Multi-Layer Information Dissemination Model And Interference Optimization Strategy For Communication Networks In Disaster Areas, Yuexia Zhang, Yang Hong, Mohsen Guizani, Sheng Wu, Peiying Zhang, Ruiqi Liu

Machine Learning Faculty Publications

The communication network in disaster areas (CNDA) can disseminate the key disaster information in time and provide basic information support for decision-making and rescuing. Therefore, it is of great significance to study the information dissemination mechanism of CNDA. However, a CNDA is vulnerable to interference, which affects information dissemination and rescuing. To solve this problem, this paper established a multi-layer information dissemination model of CNDA (MMND) which models the CNDA from the perspective of degree distribution of nodes. The information dissemination process and equilibrium state in CNDA is analyzed by an improved dynamic dissemination method. Then, the effects of the …

Self-Immolative Hydrogels With Stimulus-Mediated On-Off Degradation., Jue Gong, Aneta Borecki, Elizabeth R Gillies

Chemistry Publications

Hydrogels are of interest for a wide range of applications from sensors to drug delivery and tissue engineering. Self-immolative polymers, which depolymerize from end-to-end following a single backbone or end-cap cleavage, offer advantages such as amplification of the stimulus-mediated cleavage event through a cascade degradation process. It is also possible to change the active stimulus by changing only a single end-cap or linker unit. However, there are very few examples of self-immolative polymer hydrogels, and the reported examples exhibited relatively poor stability in their nontriggered state or slow degradation after triggering. Described here is the preparation of hydrogels composed of …

Semantically Structured Creative Computer Systems & Automated Evaluation Of Creative Artifacts, Brad Spendlove

Theses and Dissertations

Computational creativity seeks, in part, to develop autonomous agents that exhibit creativity. Language is an ideal creative domain for studying computer agents due to its rich interconnectedness and immense space of possible combinations. This dissertation explores the design, testing, and theory of creative computer systems that write microfiction and play the board game Codenames. The designs of these systems are all similarly based on building up creative artifacts from the underlying structure of the relationships between words. A critical component of the creative process is the ability to evaluate the quality of creative output. Human and automated assessment of our …

Geochemistry Of Zircon And Apatite In Rhyolites From The Central Snake River Plain: Genetic Implications, Chesley Philip Gale

Theses and Dissertations

Whole-rock and mineral compositions of three eruptive deposits from the Twin Falls caldera, associated with the Yellowstone hotspot, provide a window into melt generation and evolution for hot, dry, A-type rhyolites. Three rhyolitic units were sampled via the Kimberly drill-core as a part of project HOTSPOT, a study focused on mantle plume and continental lithosphere interaction. Previous work has been done to collect high resolution U-Pb zircon ages, and Hf- and O-isotopic compositions. This study examined the geochemistry of apatite and zircon along with host rock compositions in the context of this previous work. The Kimberly core sampled the Shoshone …

Groundwater Flow Across The Coyote Wash Fault And Cedar Mesa Anticline Near St. Johns, Arizona, Stephanie Lynn Latour

Theses and Dissertations

As the demand for water increases across the southwestern United States, the region's utilization of and dependence on water stored in groundwater aquifers has risen in kind. The Coconino Aquifer (C-aquifer) underlies much of the southwestern Colorado Plateau and is a primary source of groundwater in northeastern Arizona. One of the largest commercial users of water from the C-aquifer in Apache County, Arizona, is Springerville Generating Station, a coal-fired power plant owned and operated by Tucson Electric Power. The area surrounding the power plant, located between the cities of Springerville and St. Johns, Arizona (the Springerville-St. Johns area), is geologically …

The Student Becomes The Teacher: Training High-Performance Language Models More Sample-Efficiently From Small Models Via Superstilling, Chaz Allen Gundry

Theses and Dissertations

Recent advances including the Transformer architecture have revolutionized the Natural Language Processing community by providing immense performance improvements across many tasks, including the development of Large Language Models (LLMs). LLMs show enormous promise as few-shot learners, common-sense knowledge repositories, conversational agents, writing assistants, and coding tools, and are gaining widespread traction in commercial industry. However, LLMs are expensive and time-consuming to train, requiring many passes over terabytes of data for the largest models. In this paper, we present Superstilling, a method for reducing the sample complexity of language model training by distilling the knowledge from a previously-trained model (the teacher) …

Self-Supervised Pretraining And Transfer Learning On Fmri Data With Transformers, Sean Paulsen

Dartmouth College Ph.D Dissertations

Transfer learning is a machine learning technique founded on the idea that knowledge acquired by a model during “pretraining” on a source task can be transferred to the learning of a target task. Successful transfer learning can result in improved performance, faster convergence, and reduced demand for data. This technique is particularly desirable for the task of brain decoding in the domain of functional magnetic resonance imaging (fMRI), wherein even the most modern machine learning methods can struggle to decode labelled features of brain images. This challenge is due to the highly complex underlying signal, physical and neurological differences between …

Grounding Line And Calving Front Retreat In Glomar Challenger Basin And Pennell Trough Of Ross Sea, Antarctica Reconstructed From Diatom Abundances And Assemblages, Jaren Bradford

LSU Master's Theses

Previous studies showed that West Antarctic Ice Sheet (WAIS) retreat from the Whales Deep Basin continental shelf edge in eastern Ross Sea was underway by 14.7 ± 0.4 cal kyr BP. Following an ice-shelf breakup at 12.3 ± 0.6 cal kyr BP, a calving cliff margin remained within 60 km of the shelf edge until 11.5 ± 0.3 cal kyr BP. McGlannan et al. (2017) inferred that an ice shelf reformed immediately during a subsequent rapid retreat. That interpretation of grounding-line retreat with an intact ice shelf is being reevaluated by Sivils (in prep.). Here, we conducted a similar synthesis …

Efficient And Secure Digital Signature Algorithm (Dsa), Nissa Mehibel, M'Hamed Hamadouche

Emirates Journal for Engineering Research

The digital signature is used to ensure the integrity of messages as well as the authentication and non-repudiation of users. Today it has a very important role in information security. Digital signature is used in various fields such as e-commerce and e-voting, health, internet of things (IOT). Many digital signature schemes have been proposed, depending on the computational cost and security level. In this paper, we analyzed a recently proposed digital signature scheme based on the discrete logarithm problem (DLP). Our analysis shows that the scheme is not secure against the repeated random number attack to determine the secret keys …

Autonomous Shipwreck Detection & Mapping, William Ard

LSU Master's Theses

This thesis presents the development and testing of Bruce, a low-cost hybrid Remote Operated Vehicle (ROV) / Autonomous Underwater Vehicle (AUV) system for the optical survey of marine archaeological sites, as well as a novel sonar image augmentation strategy for semantic segmentation of shipwrecks. This approach takes side-scan sonar and bathymetry data collected using an EdgeTech 2205 AUV sensor integrated with an Harris Iver3, and generates augmented image data to be used for the semantic segmentation of shipwrecks. It is shown that, due to the feature enhancement capabilities of the proposed shipwreck detection strategy, correctly identified areas have a 15% …

Exploring New Horizons In Microwave-Promoted Iminyl Radical Chemistry And Synthesis Of Bulky Dehydroamino Acids, Jatinder Singh

Theses and Dissertations

The first project in this dissertation presents a simplified and efficient protocol for synthesizing pyrrolines through 5-exo iminyl radical cyclizations. The microwave irradiation of O-Phenyloximes tethered to alkenes causes N-O homolysis resulting in iminyl radical generation, which subsequently undergoes 5-exo-trig cyclizations furnishing pyrrolines. This eliminates the need for toxic radical initiators (AIBN, benzoyl peroxide), propagating agents (Bu3SnH, (Me3Si)3SiH), and expensive catalysts or single-electron transfer (SET) cycles. We explored the scope of diverse traps and substrates for iminyl radical cyclizations. The iminyl radical cyclizations formed versatile pyrrolines with moderate to excellent yields. The diastereoselectivity also ranged from low to high. Moreover, …

Improving Xrd Analysis With Machine Learning, Rachel E. Drapeau

Theses and Dissertations

X-ray diffraction analysis (XRD) is an inexpensive method to quantify the relative proportions of mineral phases in a rock or soil sample. However, the analytical software available for XRD requires extensive user input to choose phases to include in the analysis. Consequently, analysis accuracy depends greatly on the experience of the analyst, especially as the number of phases in a sample increases (Raven & Self, 2017; Omotoso, 2006). The purpose of this project is to test whether incorporating machine learning methods into XRD software can improve the accuracy of analyses by assisting in the phase-picking process. In order to provide …