Open Access. Powered by Scholars. Published by Universities.®
- Institution
-
- University of Nebraska - Lincoln (10566)
- University of Kentucky (10462)
- Utah State University (2395)
- Old Dominion University (2269)
- TÜBİTAK (1962)
-
- University of South Florida (1623)
- Nova Southeastern University (1321)
- Portland State University (1316)
- Louisiana State University (1260)
- University of Arkansas, Fayetteville (1201)
- University of Nevada, Las Vegas (1099)
- University of Texas Rio Grande Valley (1057)
- Missouri University of Science and Technology (970)
- University of South Carolina (903)
- Department of Primary Industries and Regional Development, Western Australia (875)
- University of Northern Iowa (862)
- Brigham Young University (860)
- City University of New York (CUNY) (818)
- Wright State University (736)
- Virginia Commonwealth University (715)
- Clemson University (629)
- Chulalongkorn University (620)
- Western Kentucky University (608)
- Technological University Dublin (592)
- University of Texas at El Paso (586)
- Marquette University (585)
- South Dakota State University (566)
- University of Central Florida (555)
- Singapore Management University (553)
- University of New Mexico (551)
- Keyword
-
- Climate change (763)
- Machine learning (595)
- Water quality (543)
- Chemistry (527)
- Western Australia (507)
-
- Grazing (435)
- Nitrogen (428)
- Sustainability (418)
- Conservation (407)
- Biodiversity (371)
- Ecology (356)
- Management (295)
- Remote sensing (289)
- Humans (288)
- Deep learning (279)
- Machine Learning (274)
- Invasive species (273)
- Environment (269)
- Nanoparticles (255)
- United States (255)
- Phosphorus (253)
- Water (244)
- Soil (234)
- Phytoplankton (232)
- Synthesis (232)
- Agriculture (231)
- Oceanography (227)
- Biology (225)
- Artificial intelligence (224)
- Cancer (224)
- Publication Year
- Publication
-
- IGC Proceedings (1977-2023) (9261)
- Theses and Dissertations (2478)
- Electronic Theses and Dissertations (1482)
- Nebraska Tractor Tests (1347)
- United States Department of Agriculture Wildlife Services: Staff Publications (1276)
-
- Turkish Journal of Chemistry (1183)
- Faculty Publications (1075)
- School of Natural Resources: Faculty Publications (957)
- USF Tampa Graduate Theses and Dissertations (820)
- Dissertations (702)
- LSU Doctoral Dissertations (602)
- Chemistry Faculty Publications (570)
- Honors Theses (555)
- Theses (544)
- Graduate Theses and Dissertations (528)
- United States Geological Survey: Staff Publications (521)
- All Graduate Theses and Dissertations, Spring 1920 to Summer 2023 (505)
- Chulalongkorn University Theses and Dissertations (Chula ETD) (495)
- LSU Master's Theses (493)
- Research Collection School Of Computing and Information Systems (488)
- The Prairie Naturalist (483)
- Masters Theses (480)
- Open Access Theses & Dissertations (474)
- Turkish Journal of Electrical Engineering and Computer Sciences (461)
- Dissertations and Theses (433)
- Journal of the Iowa Academy of Science: JIAS (406)
- OES Faculty Publications (406)
- UNLV Theses, Dissertations, Professional Papers, and Capstones (391)
- Articles (382)
- School of Earth, Environmental, & Marine Sciences Faculty Publications (371)
- Publication Type
Articles 1201 - 1230 of 78534
Full-Text Articles in Entire DC Network
Fisheries Management Paper No. 313: Western Australian Statewide Small Pelagic Scalefish Resource Harvest Strategy, Department Of Primary Industries And Regional Development, Western Australia
Fisheries Management Paper No. 313: Western Australian Statewide Small Pelagic Scalefish Resource Harvest Strategy, Department Of Primary Industries And Regional Development, Western Australia
Fisheries Management Papers
Harvest strategies for Western Australia’s (WA) aquatic resources are formal documents developed by the Department of Primary Industries and Regional Development (DPIRD, the Department) to support decision-making processes that ensure the outcomes are consistent with the principles of Ecologically Sustainable Development (ESD; Fletcher 2002a) and Ecosystem Based Fisheries Management (EBFM; Fletcher et al. 2012).
Harvest strategies are a key component of all contemporary fishery management systems and a requirement for certification under the Marine Stewardship Council (MSC; Marine Stewardship Council 2018). The objectives of ESD are reflected in the objects of the Fish Resources Management Act 1994 (FRMA).
This Statewide …
Engineering Silicone Magnetic Fluids For Localized Radiation Attenuation During Ocular Melanoma Brachytherapy, Zachary L. Caprow
Engineering Silicone Magnetic Fluids For Localized Radiation Attenuation During Ocular Melanoma Brachytherapy, Zachary L. Caprow
All Dissertations
Ocular melanoma is commonly treated using plaque brachytherapy; however, radiation-induced damage to healthy ocular tissues frequently results in partial or complete vision loss. This work investigates the development of an injectable, magnetically responsive silicone magnetic fluid designed to localize adjacent to the tumor and attenuate low-energy gamma radiation during treatment.
The material system consists of iron oxide nanoparticles surface-functionalized with a siloxane polymer, in which the nanoparticles provide magnetic responsiveness and radiation attenuation, while the polymer coating ensures colloidal stability, injectability, and biocompatibility. A one-pot synthetic approach was developed wherein a functionalized siloxane polymer containing iron-affinitive groups was reacted with …
Stability Of Paraffin-Insulated Nitrogen-Doped Carbon Fiber Ultramicroelectrodes, Maxwell H. Kwakwah
Stability Of Paraffin-Insulated Nitrogen-Doped Carbon Fiber Ultramicroelectrodes, Maxwell H. Kwakwah
Electronic Theses and Dissertations
Nitrogen-doped carbon materials can facilitate the reduction oxygen-oxygen bonds, a key step in electroreduction of both O2 (an important reaction in energy applications) and H₂O₂ (an important reaction in sensing and biosensing). Our lab previously demonstrated that thermal decomposition of urea in the presence of carbon fiber (CF) results in an N-doped carbon material that exhibits good electrocatalytic properties for H₂O₂ reduction. However, previous methods of insulating single N-doped CF via laser heating of borosilicate capillaries and epoxy to prepare ultramicroelectrodes (UMEs) seemed to adversely affect surface nitrogen contents and electrocatalytic properties. More recent work that utilized paraffin to …
Course Insight Portfolio: Math 1020 Business Calculus I, Ibrahim Khalilullah, M.G.M. Al Faruque, Jessica Ratovondranto, Leslie Spahr
Course Insight Portfolio: Math 1020 Business Calculus I, Ibrahim Khalilullah, M.G.M. Al Faruque, Jessica Ratovondranto, Leslie Spahr
Publications
This portfolio presents an overview of the student educational context, key course concepts, and some approaches to clarify student misconceptions associated with MATH 1020 (Business Calculus I). The portfolio includes a concept map illustrating the major topics of the course and an overview of common student misconceptions, and lesson plans designed to address those misconceptions through research informed instructional practices.
The concept map highlights the interconnected nature of topics such as functions, limits, continuity, differentiability, derivatives, optimization, graph interpretation, and applications of calculus. Particular attention is given to areas where students commonly experience difficulty, including distinguishing domain, codomain, and range; …
The Hitchhiker's Guide To The Host: Fleas And The History Of Pikas In North America, Josh Pletcher
The Hitchhiker's Guide To The Host: Fleas And The History Of Pikas In North America, Josh Pletcher
All NMU Master's Theses
Parasite phylogenetics can offer windows into the cryptic evolutionary history of hosts, often highlighting events that are not recorded by the phylogenetics of the host. Pikas (small lagomorphs) host a diverse parasite community comprising endoparasites (e.g., coccidians, nematodes, and cestodes) and ectoparasites (e.g., fleas and mites). Phylogenetic analysis of pika endoparasites has revealed pikas evolved in Asia and colonized North America in two waves, and that contact between these two pika lineages allowed parasites to be transferred from one lineage to another and to survive the extinction of their original host. To uncover these cryptic histories, understanding the biogeography of …
Population Structure And Connectivity Of Atlantic Nurse Sharks (Ginglymostoma Cirratum) In The Bahamas And Outlying Areas, Baylie A. Fadool
Population Structure And Connectivity Of Atlantic Nurse Sharks (Ginglymostoma Cirratum) In The Bahamas And Outlying Areas, Baylie A. Fadool
School of Natural Resources: Dissertations, Theses, and Student Research
Understanding animal ecosystem dynamics and behavior at the individual and population levels is essential for identifying life-history patterns and important areas for management and conservation. Marine fish species often face minimal geographic barriers to movement, but environmental (temperature, salinity, current) or intrinsic barriers (philopatry, site fidelity) can dictate gene flow. Atlantic nurse sharks (Ginglymostoma cirratum) are an International Union for Conservation of Nature (IUCN) listed ‘vulnerable’ species and present a unique opportunity to investigate patterns of population structure and connectivity in large-bodied sharks. They are benthic and display reproductive philopatry, with recent work suggesting they have the capacity …
Gaining Mussel: Evaluating Reintroduction Success Of Native Freshwater Mussels In Nebraska And Eastern Wyoming, Travis A. Moore
Gaining Mussel: Evaluating Reintroduction Success Of Native Freshwater Mussels In Nebraska And Eastern Wyoming, Travis A. Moore
School of Natural Resources: Dissertations, Theses, and Student Research
Freshwater mussels are one of the most imperiled groups of organisms in North America, with over two-thirds of species considered threatened, endangered, or of special concern. These long-lived bivalves are essential to stream ecosystems, acting as filter feeders that improve water quality and as indicators of aquatic health. In Nebraska and Wyoming, native mussel populations have declined sharply due to habitat modification, pollution, and reduced connectivity. Two species of particular concern are the Plain Pocketbook Lampsilis cardium, listed as Tier I at-risk in Nebraska, and the Fatmucket Lampsilis siliquoidea, a Tier II at-risk species. In response, state agencies …
Impact Of Biomass Type On Hydrocarbon Yield And Chain Length Distribution Produced Via Fischer-Tropsch Synthesis, Nicholas R. Hawe
Impact Of Biomass Type On Hydrocarbon Yield And Chain Length Distribution Produced Via Fischer-Tropsch Synthesis, Nicholas R. Hawe
Honors Scholar Theses
This paper investigates the relationship between biomass composition and hydrocarbon yield as well as chain length distribution produced by Fischer-Tropsch synthesis. Through an Aspen Plus model, the conversion of three different biomasses – digestate, sawdust, and corn stover – into hydrocarbon fuel was simulated. The model converts biomass into gaseous and liquid hydrocarbons via various unit operations and reactions. Simulation results highlight the product distribution and hydrocarbon output, allowing for an analysis of hydrocarbon yield and comparison of chain length distributions amongst the three biomasses. Overall, the simulation showed biomass composition had no significant impact on hydrocarbon yield or chain …
Multiplexing Reductive Alkylation Of Peptides For Quantitative Proteomics, Kevin C. Souza
Multiplexing Reductive Alkylation Of Peptides For Quantitative Proteomics, Kevin C. Souza
Honors Scholar Theses
Reductive alkylation is a robust and commonly used labeling technique for quantifying proteins and peptides in complex samples using mass spectrometry. This technique involves the attachment of alkyl groups to an amino group at the N-terminus and lysine residues of a peptide, causing a mass shift that is detectable using mass spectrometry. This work aims to explore the application of reductive alkyl labeling in multiplexed quantitative proteomics. The first part of the study investigates the effectiveness of the labeling of peptides using a variety of aldehydes via reductive alkylation. The aldehydes were chosen, such that they provided various degrees of …
Reversible, Light-Controlled Inhibition Of Stim1-Mediated Calcium Signaling Using Photoswitchable Ml-9 Derivatives In Jurkat-Lucia Nfat Reporter T Cells, José L. Matute Gálvez
Reversible, Light-Controlled Inhibition Of Stim1-Mediated Calcium Signaling Using Photoswitchable Ml-9 Derivatives In Jurkat-Lucia Nfat Reporter T Cells, José L. Matute Gálvez
Honors Scholar Theses
Store-operated calcium entry (SOCE) through calcium release-activated
calcium (CRAC) channels is the dominant pathway for sustained Ca2+ influx in
non-excitable cells and is essential for T cell activation, driving downstream
signaling through the calcineurin-NFAT transcriptional axis. Dysregulation of
SOCE produces multi-systemic disease phenotypes, establishing that precise,
spatiotemporally controlled modulation of this pathway is a fundamental
therapeutic requirement. ML-9 is one of the only characterized small molecules
capable of targeting SOCE upstream at the level of STIM1 localization, but lacks
the selectivity, pharmacokinetic properties, and spatiotemporal control necessary
for therapeutic development.
This work describes the design, synthesis, and biological evaluation of …
Combinatorial Statistics Witnessing An Infinite Family Of Congruences For A Sum Of Partition Functions, Jena M. Gregory
Combinatorial Statistics Witnessing An Infinite Family Of Congruences For A Sum Of Partition Functions, Jena M. Gregory
Theses and Dissertations
In 2007, Kronholm established The Interval Theorem, infinite families of congruences in arithmetic progression, modulo any prime ��, for ��(��, ��), the function enumerating the partitions of �� into parts whose sizes come from the set {1, 2, … , ��}. In 2022, Eichhorn, Kronholm, and Larsen proved there are combinatorial statistics described in terms of the multiplicities of the part sizes that witness Kronholm’s Interval Theorem. Here, “witness" means given a congruence of the form ��(��, ��) ≡ 0 (mod ��), we can use these statistics to classify the set of partitions of �� into �� equally sized subsets …
General Chemistry Students' Perceptions Of How Various Course Resources Affect Their Learning And Exam Preparation, Jennifer Scoggin Cortez
General Chemistry Students' Perceptions Of How Various Course Resources Affect Their Learning And Exam Preparation, Jennifer Scoggin Cortez
Theses and Dissertations
The tertiary-level first-semester general chemistry course has a large range of material with different complexities that can be difficult for students to master within one semester. In the general chemistry I course under study here, students were provided with a variety of resources to help with their learning and understanding, with various components of the course, including the lecture, online textbook, Peer-Led-Team-Learning (PLTL) study sessions, and exams, having associated resources. This study aims to analyze students’ experiences with these various resources. Students were given semi-structured interviews where they talked about their experiences with the resources and provided insight into more …
Assessing Water Quality And Nitrogen Dynamics In Bahia Grande, Texas Using Field And Remote Sensing Data, Sk Taufiqul Islam
Assessing Water Quality And Nitrogen Dynamics In Bahia Grande, Texas Using Field And Remote Sensing Data, Sk Taufiqul Islam
Theses and Dissertations
An 8,220-acre estuary in South Texas, Bahia Grande has recently been restored from a disconnected hypersaline basin to a tidal estuary. A spatially explicit water quality index (WQI) was developed and in situ physicochemical data coupled with remote sensing data from Sentinel-2 were used to determine ecological integrity. A WQI from 29.45-53.20 yielded a spatial distribution of water quality that displayed a non-linear spatial trend throughout the estuary. Water quality close to the Brownsville Ship Channel inlet yielded values of 'Moderate/Stressed' water quality (> 50). These areas represent local zones of disturbance where ammonium concentrations were more than 11 µmol/L. …
A Visit-Count-Based Complete Foraging Strategy For Robot Swarms, Arturo Yahir Gonzalez
A Visit-Count-Based Complete Foraging Strategy For Robot Swarms, Arturo Yahir Gonzalez
Theses and Dissertations
Swarm robotics systems often rely on a balance between exploration and exploitation to perform tasks like Central Place Foraging. While exploitation methods such as pheromone trails and site fidelity are well-studied, the efficiency of the underlying random search exploration remains a challenge, frequently leading to redundant coverage and wasted time as multiple agents repeatedly search the same fruitless areas. This thesis introduces a memory-enhanced exploration strategy designed to improve the efficiency of random search in a swarm of simple robots.
In our proposed algorithm, each robot, constrained with limited memory, periodically logs its recent locations while exploring. This spatial data …
Probing The Dynamic Behavior Of The Androgen Receptor In The Presence Of Heptyl And Methyl Parabens, Edgardo De Leon
Probing The Dynamic Behavior Of The Androgen Receptor In The Presence Of Heptyl And Methyl Parabens, Edgardo De Leon
Theses and Dissertations
The androgen receptor (AR) mediates physiological signaling from endogenous androgens, a function that can be disrupted by endocrine disruptors with serious reproductive and developmental consequences. Parabens, widely used preservatives, inhibit AR signaling in cell-based assays, with inhibitory potency correlating with alkyl chain length: heptylparaben exhibits stronger antagonism than methylparaben, which shows no effect. We hypothesize this differential potency arises from allosteric modulation at the AR Binding Function 3 (BF-3) site, altering dihydrotestosterone (DHT) binding dynamics. Docking calculations using antagonist-bound AR crystal structures, followed by molecular dynamics simulations, show that methylparaben fails to remain bound at BF-3, whereas heptylparaben maintains stable …
Morphological Evolution And Sediment Budget Of A Flood-Tidal Delta On The Rio Grande Delta Plain: Bahia Grande, Texas, Usa, Aleen Pertuz Paz
Morphological Evolution And Sediment Budget Of A Flood-Tidal Delta On The Rio Grande Delta Plain: Bahia Grande, Texas, Usa, Aleen Pertuz Paz
Theses and Dissertations
The Isabel Delta is a recently formed flood-tidal delta within the restored Bahia Grande system on the Rio Grande Delta Plain, Texas, USA, where renewed tidal connectivity has created conditions for rapid sediment buildup and landform evolution. This study quantified morphological changes from 2008 to 2025 using satellite imagery. It assessed sediment retention by comparing the effective sediment discharge required to reproduce observed delta growth with field-based estimates of sediment supply derived from channel hydrodynamics, cross-sectional area, and suspended sediment concentration. The delta expanded steadily throughout the study period, with increases in bar, channel, and total surface area, and an …
Soil Water Content Beneath Agrivoltaic Installations In A Subtropical Semi-Arid Climate, John Justin Rodriguez
Soil Water Content Beneath Agrivoltaic Installations In A Subtropical Semi-Arid Climate, John Justin Rodriguez
Theses and Dissertations
Agrivoltaics (AV) not only beneficially influences agricultural microclimates in the field, AV systems can generate on-site energy to offset operational costs, diversify income sources, and improve overall resilience, while providing environmental co-benefits such as reduced heat stress on plants and improved resource use efficiency. This thesis evaluated agrivoltaic shading effects on SWC and soil temperature using high-resolution in situ measurements collected over one year in an active vineyard, incorporating row type, soil depth, shading, and time of day. With precipitation as the primary water source, shaded soils exhibited up to 24.53% lower SWC relative to sun-exposed soils, likely due to …
Structure–Property Engineering Of Sn-Based Hybrid Perovskites Via Bulky Organic Cation Incorporation: From 3d To 2d Architectures, Kevin Alejandro
Structure–Property Engineering Of Sn-Based Hybrid Perovskites Via Bulky Organic Cation Incorporation: From 3d To 2d Architectures, Kevin Alejandro
Theses and Dissertations
This thesis investigates tin-based hybrid organic/inorganic perovskites (HOIPs) as a lead-free alternative to silicon solar cells. To manipulate optoelectronic and efficiency of the semiconductors, methylammonium was substituted with bulky propylammonium and tetrabutylammonium cations to induce quasi-2D/3D Ruddlesden-Popper phases. X-Ray Diffraction confirmed 2D layered phases in propylammonium hybrids (5-15%), while tetrabutylammonium hybrids faced steric limits, triggering vacancy ordered perovskite phases at 1% concentration. Optical analysis showed a bandgap narrowing from 1.30 eV to 1.26 eV with increased substitution. Although photovoltaic performance generally declined, the 10% propylammonium hybrid achieved the highest fill factor of ~0.79, indicating superior internal charge transport. This work …
Impaired Tunability Of Brain State And Motor Dysfunction In A Mouse Model Of Rett Syndrome, Victoria Kindler Norman
Impaired Tunability Of Brain State And Motor Dysfunction In A Mouse Model Of Rett Syndrome, Victoria Kindler Norman
Graduate Theses and Dissertations
Rett syndrome (RTT) is a rare neurological disorder, caused by disrupted function of the MECP2 gene, resulting in impaired cognitive and motor functions. Previous studies suggest that although MECP2 has important functions throughout the body, the etiological origins of RTT-related dysfunction should be sought within the brain. However, it remains a mystery how neural population dynamics are altered in the RTT brain and how these alterations relate to motor dysfunction. Previous studies using an RTT mouse model point to abnormal correlations among firing rates of neurons. Here we hypothesize that such disrupted neural activity correlation could be caused by abnormal …
A Survey On Digital Reading Materials And Personal Study Of Christian Religious Texts, Teancum Price
A Survey On Digital Reading Materials And Personal Study Of Christian Religious Texts, Teancum Price
All Graduate Theses and Dissertations, Fall 2023 to Present
Religion, including reading from religious texts such as scriptures, are a part of the daily lives of many people. Modern technology has influenced the way that this religious reading takes place, but its effects have not yet been studied. Existing research of the effects of technology on reading focus on topics such as reading comprehension, but the study of religious texts is often focused on achieving a religious experience, so the existing research does not capture the whole scope of these changes. In our study, we surveyed two universities (Utah State University and Abilene Christian University) to ask individuals how …
Separating And Identifying Delta-8-Thc And Delta-9-Thc On Gc/Ms, Ann Schmidt
Separating And Identifying Delta-8-Thc And Delta-9-Thc On Gc/Ms, Ann Schmidt
Honors Projects
Delta-8-THC and delta-9-THC are two psychoactive compounds found in marijuana products which are only distinguishable from each other by alternating the location of a single double bond. This makes them a challenge to separate and identify as different compounds using the GC/MS. These isomers are legally recognized as the different compounds, so being able to identify delta-8 and delta-9 THC separately is crucial to forensic analysis. The goal of this research project is to optimize an Intuvo 9000 GC connected to a standard MS to be able to separately and prominently identify delta-8-THC and delta-9-THC in a sample. This was …
Constraint-Aware Metaheuristic Optimization For Experimental Design, Benjamin N. Fuller
Constraint-Aware Metaheuristic Optimization For Experimental Design, Benjamin N. Fuller
All Graduate Theses and Dissertations, Fall 2023 to Present
Designing experiments becomes much more challenging when many variables and strict constraints are involved, as is common in modern science and engineering. This thesis introduces a new computational and mathematical framework that efficiently searches for optimal experiments in complex, high-dimensional spaces where traditional methods fail. By combining geometric techniques with flexible optimization algorithms like particle swarm optimization, our methods handle difficult constraints while scaling to real-world problems. Built in the high-performance Julia programming language and released as open-source software, this work bridges advanced theory with practical tools, offering researchers a powerful and accessible way to design better experiments under realistic …
From Data Digitization To Personalized Care: Deep Learning And Decision Analytics In Healthcare Systems, Ahla Ko
Graduate Theses and Dissertations
This dissertation traces a progression from foundational data infrastructure to individualized clinical decision-making, developing and evaluating three computational frameworks that advance healthcare efficiency and personalization through deep learning and decision analytics. The first study presents an end-to-end pipeline for automated recognition of handwritten medical forms, addressing persistent challenges in health data digitization. Integrating a YOLO-based field detection model, a Convolutional Recurrent Neural Network (CRNN) for text transcription, and a confidence-based human-in-the-loop quality assurance framework, the system achieved 99.75\% Exact Match Accuracy and a 0.13\% Character Error Rate on medical forms collected from a tuberculosis research project in Moldova. A GPU-accelerated …
Quantifying Macrophyte Ecosystem Services And Improving Environmental Nonprofit Messaging, Peyton R. Hughey
Quantifying Macrophyte Ecosystem Services And Improving Environmental Nonprofit Messaging, Peyton R. Hughey
All Theses
Environmental nonprofits are essential to the management and restoration of our natural spaces. They are also tasked with engaging the public via outreach, education, and advocacy. As natural spaces are degraded, the ability of environmental nonprofits to deliver on their missions will become increasingly important. This study aimed to improve two approaches to environmental nonprofits’ missions: ecological restoration and social media communication.
Environmental nonprofits operate with limited resources, and ecological restoration can be an exhaustive task; therefore, we explore functional restoration as a tool. In this study, we focus on the use of functional, trait-based restoration to restore ecological function …
Taking A Deeper Look: Attributing Tonal Values Of Photolumens To Their Emulsions Using Scanning Electron Microscopy, Anna M. Moore
Taking A Deeper Look: Attributing Tonal Values Of Photolumens To Their Emulsions Using Scanning Electron Microscopy, Anna M. Moore
All Theses
This thesis examines whether tonal variation in photolumens made with historic silver gelatin photographic papers can be linked to differences in elemental composition. Photolumens are cameraless photographic images created by placing objects directly on light-sensitive paper and exposing them to ultraviolet light. Because expired and historic darkroom papers often produce unpredictable colors and tones, this study asks whether visually defined tonal groups also show measurable chemical differences.
Twenty historic paper samples were exposed, documented, and sorted into five tonal groups based on visible image characteristics. Each sample was then analyzed using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) …
Stochastic Universal Differential Equations For Epidemiological Modeling: Uncertainty Quantification In Disease Transmission Dynamics, Alice Menaya Armah-Bonney
Stochastic Universal Differential Equations For Epidemiological Modeling: Uncertainty Quantification In Disease Transmission Dynamics, Alice Menaya Armah-Bonney
Electronic Theses and Dissertations
Epidemic forecasting requires not only predictions of expected case counts, but also quantification of uncertainty, although existing surrogate modeling frameworks for agent-based models remain fundamentally deterministic. In this thesis a Stochastic Universal Differential Equation framework is presented that extends the deterministic Universal Differential Equation approach by incorporating a learnable stochastic diffusion term, enabling calibrated probabilistic forecasts while preserving the mechanistic interpretability and computational efficiency of the deterministic baseline. In doing so, a two-phase training algorithm is introduced to ensure stable convergence and the framework is validated against the ensemble output from ExaEpi, an exascale agent-based model of a COVID-19 outbreak …
Ontogeny And The Effects Of Perinatal Stress In The First Immature Skeleton Of Teleoceras Aepysoma (Perissodactyla, Rhinocerotidae), Joe Gajewski
Electronic Theses and Dissertations
Recovery of an immature fossil rhinoceros (Teleoceras aepysoma) skeleton (ETMNH 32999) from the Gray Fossil Site in Tennessee offers the first insights into the ontogeny of the species. ETMNH 32999 is interpreted to be a subadult male in an age class equivalent to ~17-20% of potential lifespan. Comparative analyses support the hypothesis that subadults of related taxa are typically ~91% of average adult size in most dimensions. However, certain cranial dimensions are substantially lower than expected in ETMNH 32999, averaging only ~74% of the average conspecific adult. Such departure from typical growth rates is suggested to be attributable …
Utilizing Physics Informed Neural Networks For Disrupted Signal Dynamics, Nicholas J. Joyner
Utilizing Physics Informed Neural Networks For Disrupted Signal Dynamics, Nicholas J. Joyner
Electronic Theses and Dissertations
Physics-informed neural networks (PINNs) have been used in many applications including engineering and physical sciences. PINNs allow the incorporation of a priori understanding of a process’ structure into the modeling. We attempt to leverage the PINN structure toward the evaluation of disruptions to classical dynamical models by combining elements of ordinary differential equations into our loss function with sigmoidal gating to balance the penalties for deviations from the data with those for structural deviations. This enables the identification of the signal structure and the limits of disruption influence. As a use case, we consider stock value from 2019-2021, which expresses …
Optimisation Of Photosensitive Recording Materials For Broadband Holographic Optical Elements, Michael Murray
Optimisation Of Photosensitive Recording Materials For Broadband Holographic Optical Elements, Michael Murray
Doctoral
The introduction of broadband (white) LED outdoor lighting has led to significant energy savings. However, this has come at the cost of increased light pollution which has negative impacts both on ecological systems and human health. This light pollution is largely the result of the lack of control measures for the directionality of the light emitted by outdoor LED lighting. The lack of directionality also results in higher energy consumption in order to compensate for the light scattered to the atmosphere and sufficiently illuminate the target area. In this thesis holographic optical elements (HOEs) are proposed as a complementary technology …
Degradation And Metabolic Analysis Of Synthesized Quorum-Sensing Signals By The Model Eukaryote Chlamydomonas Reinhardtii, Adam Josef Bach
Degradation And Metabolic Analysis Of Synthesized Quorum-Sensing Signals By The Model Eukaryote Chlamydomonas Reinhardtii, Adam Josef Bach
Theses and Dissertations
Bacterial organisms can “talk” with one another on a colony-wide scale using a communication system known as quorum-sensing (QS) via chemical signals. These signals are produced at a basal rate throughout the life of the bacteria and are classified as autoinducers, which diffuse across the cell membrane. Once the critical concentration is reached, they begin to diffuse back into the cell and initiate a phenotypic change. As these signals exist outside the membrane of their producer, they are also accessible to other organisms. It has already been noted that some plant species uptake these compounds through their roots and break …