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Full-Text Articles in Physical Sciences and Mathematics

Monitoring Methods And Performance Assessment For Implementation Of Low Impact Development Practices In South Dakota, Farhana Akhter Jan 2020

Monitoring Methods And Performance Assessment For Implementation Of Low Impact Development Practices In South Dakota, Farhana Akhter

Electronic Theses and Dissertations

Urbanization increases impervious surface area, which changes the hydrology of a watershed. Impervious surfaces prevent the infiltration of stormwater water into the ground surface which results in a higher volume of stormwater runoff and higher peak flow. Low Impact Development (LID) practices help to restore pre-development hydrology by increasing infiltration, evaporation, and transpiration. While the hydrologic performance of LID practices has been studied extensively and continues to be an area of active research, there has been very limited monitoring or demonstration of LID practices in South Dakota. In addition, municipalities in South Dakota and elsewhere that implement new LID practices …


Development Of Analytical Methods For Toxic Inhaled Hazards (Tih) And Their Metabolites, Obed Adu Gyamfi Jan 2020

Development Of Analytical Methods For Toxic Inhaled Hazards (Tih) And Their Metabolites, Obed Adu Gyamfi

Electronic Theses and Dissertations

Toxic inhalation hazards (TIHs), such as methyl isocyanate (MIC) and hydrogen cyanide (HCN), are noxious gases and vapors that are harmful, and often deadly, to humans. However, because of their low cost and high reactivity, they are extensively used for industrial productions, creating risk of exposure for both industrial workers (e.g., occupational exposure) and civilians (e.g., accidental release during transport). The illicit use of TIHs, including as terrorist agents, is also concerning. Considering the rapid toxicity of TIHs and the danger they pose to both human and animal lives, there is a critical need to develop of analytical methods for …


Understanding How Agricultural Intensification Impacts Ring-Necked Pheasant Distribution And Survival In Eastern South Dakota, Hilary R. Kauth Jan 2020

Understanding How Agricultural Intensification Impacts Ring-Necked Pheasant Distribution And Survival In Eastern South Dakota, Hilary R. Kauth

Electronic Theses and Dissertations

Historically, pheasants (Phasianus colchicus) have thrived in South Dakota in conjunction with successful land retirement programs or early farming practices through the 1950s, which created interspersions of agriculture and native landscapes that were ideal for pheasants. Recently, the Prairie Pothole ecosystem has undergone rapid agroeconomic expansion, effectively reducing ideal interspersions of native prairie and cropland into agriculturally homogeneous landscapes. Indices of pheasant abundance have suggested persistent population declines since 2008, raising concerns regarding landscape suitability. Our goal was to understand how agriculture intensification impacts pheasant ecology. The objectives were to: 1) estimate overwinter hen probability of survival, resource …


Soil Physical And Hydrological Properties, And Greenhouse Gas Emissions Under Integrated Crop-Livestock Agroecosystems, Navdeep Singh Jan 2020

Soil Physical And Hydrological Properties, And Greenhouse Gas Emissions Under Integrated Crop-Livestock Agroecosystems, Navdeep Singh

Electronic Theses and Dissertations

Cover crops (CCs) and grazing play a critical role in successful implementation of the integrated crop-livestock system (ICLS) because they can have a direct impact on soils and greenhouse gas emissions. The objectives of this study were to (i) evaluate the short-term impacts of CCs [grass dominated cover crops (GdC) and legume dominated cover crops (LdC)] and grazed CCs and corn (Zea mays L.) residue under oat (Avena sativa L.)–CC–corn rotation on soil physical and hydrological properties; (ii) quantify the architecture of soil pores using X-ray computed tomography (CT) for soils managed under long-term ICLS, native grazed pasture and corn-soybean …


Biophysical And Socioeconomic Impacts Of Farmer Managed Natural Regeneration In Burkina Faso, Basnewende Brice Fulgence Zoungrana Jan 2020

Biophysical And Socioeconomic Impacts Of Farmer Managed Natural Regeneration In Burkina Faso, Basnewende Brice Fulgence Zoungrana

Electronic Theses and Dissertations

Human actions such as overgrazing, the development of cities at the expense of forests, high intensity and poor agricultural management, and so forth, reduce the resources available for future generations. Because Earth has limited resources, it is important to judiciously use and manage natural resources. Human actions towards nature are the focus of my research in Africa. Increased demands for grazing, agriculture, and ecosystem services led some farmers in developing countries to use unsustainable practices, which may lead to low incomes and poor food nutrition for households. Farmer managed natural regeneration (FMNR) may be a solution to these issues. FMNR …


Phytoremediation Of Saline-Sodic Soils In East Central South Dakota Utilizing Perennial Grass Mixtures, Douglas J. Fiedler Jan 2020

Phytoremediation Of Saline-Sodic Soils In East Central South Dakota Utilizing Perennial Grass Mixtures, Douglas J. Fiedler

Electronic Theses and Dissertations

Several decades of above average precipitation in South Dakota has increased the area of saline and sodic soils, which reduce crop yields and inhibit sensitive plant growth. Saline and sodic soils are difficult to remediate using traditional agricultural crops. Establishing salt tolerant perennial species may restore productivity to salt affected areas. Two perennial grass mixtures (mix 1: slender wheatgrass, beardless wildrye; mix 2: slender wheatgrass, western wheatgrass, green wheatgrass, creeping meadow foxtail) were dormant frost seeded along a topographic gradient in Clark Co., SD. Soils were Forman-Cresbard loam and a Cresbard-Cavour loam with surface electrical conductivity (EC1:1) that …


Burning With Potential: Understanding The Relationship Between Biochar And Agriculture Of The Northern Glaciated Plains Ecoregion, Kaitlyn Abrahamson Jan 2020

Burning With Potential: Understanding The Relationship Between Biochar And Agriculture Of The Northern Glaciated Plains Ecoregion, Kaitlyn Abrahamson

Electronic Theses and Dissertations

Achieving global sustainable agriculture is one of the most incredible challenges of this century, yet many continue to try to solve this problem through the development of precision technologies. Biotechnologies, such as biochar, can perform like a precision technology while protecting agricultural land from soil erosion and fertility loss. The Northern Glaciated Plains ecoregion of the United States is little researched in the benefits from the use of biochar through improved soil nutrient capture and water retention, crop health improvements, and yield increases. The study plot has four sections of corn stover biochar and eight sections of control sections. This …


Winter Patch Grazing, Patch Burn Grazing, And Bird Communities In Western South Dakota, Jennifer Lutze Jan 2020

Winter Patch Grazing, Patch Burn Grazing, And Bird Communities In Western South Dakota, Jennifer Lutze

Electronic Theses and Dissertations

Ground nesting bird species are on a considerable decline and research efforts are being made to increase these populations throughout the Great Plains. Ground nesting bird communities found in the Northern Great Plains are driven greatly by varying amounts of cover and area size. Past research implemented patch-burn grazing to increase structural heterogeneity and to increase grassland bird habitat in the tallgrass prairie. While bird populations were very responsive to this management in the Northern Great Plains fire management is viewed negatively, especially for Midwest cattle ranchers. We implemented research to determine if winter-patch grazing on mixed grass prairie could …


Reduced Dataset Neural Network Model For Manuscript Character Recognition, Mohammad Anwarul Islam Jan 2020

Reduced Dataset Neural Network Model For Manuscript Character Recognition, Mohammad Anwarul Islam

Electronic Theses and Dissertations

The automatic character recognition task has been of practical interest for a long time. Nowadays, there are well-established technologies and software to perform character recognition accurately from scanned documents. Although handwritten character recognition from the manuscript image is challenging, the advancement of modern machine learning techniques makes it astonishingly manageable. The problem of accurately recognizing handwritten character remains of high practical interest since a large number of manuscripts are currently not digitized, and hence inaccessible to the public. We create our repository of the datasets by cropping each letter image manually from the manuscript images. The availability of datasets is …


Association Rules Patterns Discovery From Mixed Data, Welendawa Acharige Charith A. Elson Jan 2020

Association Rules Patterns Discovery From Mixed Data, Welendawa Acharige Charith A. Elson

Electronic Theses and Dissertations

Finding Association Rules has been a popular unsupervised learning technique for dis covering interesting patterns in commercial data for well over two decades. The method seeks groups of data attributes and their values where their probability density of these attributesattherespectivevaluesismaximized. Therearecurrentlywell-establishedmeth ods for tackling this problem for data with categorical (discrete) attributes. However, for the cases of data with continuous variables, the techniques are largely focusing on cate gorizing continuous variables into intervals of interest and then relying on the categorical data methods to address the problem. We address the problem of finding association rules patterns in mixed data by …


Quantification Of Dynamic Epithelial Sheet Architecture In Botryllus Schlosseri Using 2-D & 3-D Image Analysis, Roopa Madhu Jan 2020

Quantification Of Dynamic Epithelial Sheet Architecture In Botryllus Schlosseri Using 2-D & 3-D Image Analysis, Roopa Madhu

Electronic Theses and Dissertations

Epithelial tubules form critical structures in various body tissues; how- ever, since they are difficult to access experimentally, their architecture and dynamics are not well understood. Here we examine the dynamic remodeling of epithelial tubes in vivo using a novel and uniquely accessible model system: the extracorporeal vasculature of Botryllus schlosseri (sea squirt). In Botryllus, massive retraction of blood vessels can be triggered without loss of barrier function, through (i) disrupting collagen crosslinking in the basement membrane using β-aminopropionitrile (BAPN); or (ii) disrupting the integrin pathway through inhibition of focal adhesion kinase (FAK). We performed stereographic projections of 3-dimensional …


Iron In Urban Air Pollution, Joseph R. Salazar Jan 2020

Iron In Urban Air Pollution, Joseph R. Salazar

Electronic Theses and Dissertations

The processes by which iron is solubilized are largely unknown. There are three hypotheses on how iron is soluble: 1) iron is thought to undergo an acid based solubilization process, 2) iron undergoes an oxidation/reduction process and reduces iron(III) to the more soluble iron(II), and 3) iron is bound to organic molecules, which solubilizes it. The 3 hypotheses on iron water-solubilized are explored by presenting two individual studies.

The first study investigates iron directly from car exhaust. Exhaust particles were collected from 32 vehicles. Iron solubility in these samples ranged from 0%-82% with the average iron solubility being 30%. X-ray …


The Experiences Of Ncaa Student-Athletes With An Eating Disorder Or Disordered Eating, Rachel E. Taylor Jan 2020

The Experiences Of Ncaa Student-Athletes With An Eating Disorder Or Disordered Eating, Rachel E. Taylor

Electronic Theses and Dissertations

The purpose of this study was to explore the experiences of student-athletes who had an eating disorder or disordered eating (ED/DE) while competing for the National Collegiate Athletic Association (NCAA). Integrating criticism and connoisseurship and critical evocative portraiture, four post-collegiate women who participated in cross country and track, who were either clinically diagnosed with an ED/DE or who self-diagnosed, participated in two interviews to describe their experiences with and the impact of ED/DE on their athletic pursuits, academic pursuits, as well as their relationships with coaches, teammates, and family. The analysis of these interviews showed the complexity of this topic. …


Renewable Energy Integration In Distribution System With Artificial Intelligence, Yi Gu Jan 2020

Renewable Energy Integration In Distribution System With Artificial Intelligence, Yi Gu

Electronic Theses and Dissertations

With the increasing attention of renewable energy development in distribution power system, artificial intelligence (AI) can play an indispensiable role. In this thesis, a series of artificial intelligence based methods are studied and implemented to further enhance the performance of power system operation and control.

Due to the large volume of heterogeneous data provided by both the customer and the grid side, a big data visualization platform is built to feature out the hidden useful knowledge for smart grid (SG) operation, control and situation awareness. An open source cluster calculation framework with Apache Spark is used to discover big data …


Public Perception Of Different Planting Techniques Using Augmented Reality, Sultana Quader Tania Jan 2020

Public Perception Of Different Planting Techniques Using Augmented Reality, Sultana Quader Tania

Electronic Theses and Dissertations

The objective of this study was to measure public perception of the different planting techniques (block and matrix), which are used at visitor information centers (VICs) and other rights of way (ROW) areas. The main factors that affect public perception of planting techniques were identified through an extensive literature review and qualitative survey from four welcome centers in the state of Georgia. The ranking of those indicators, based on public preferences, was discovered through a quantitative survey. During the first phase of the quantitative survey, images of block and matrix were used. An iOS-based user-friendly and cost-effective augmented reality (AR) …


Nonparametric Misclassification Simulation And Extrapolation Method And Its Application, Congjian Liu Jan 2020

Nonparametric Misclassification Simulation And Extrapolation Method And Its Application, Congjian Liu

Electronic Theses and Dissertations

The misclassification simulation extrapolation (MC-SIMEX) method proposed by Küchenho et al. is a general method of handling categorical data with measurement error. It consists of two steps, the simulation and extrapolation steps. In the simulation step, it simulates observations with varying degrees of measurement error. Then parameter estimators for varying degrees of measurement error are obtained based on these observations. In the extrapolation step, it uses a parametric extrapolation function to obtain the parameter estimators for data with no measurement error. However, as shown in many studies, the parameter estimators are still biased as a result of the parametric extrapolation …


Generalization Of Kullback-Leibler Divergence For Multi-Stage Diseases: Application To Diagnostic Test Accuracy And Optimal Cut-Points Selection Criterion, Chen Mo Jan 2020

Generalization Of Kullback-Leibler Divergence For Multi-Stage Diseases: Application To Diagnostic Test Accuracy And Optimal Cut-Points Selection Criterion, Chen Mo

Electronic Theses and Dissertations

The Kullback-Leibler divergence (KL), which captures the disparity between two distributions, has been considered as a measure for determining the diagnostic performance of an ordinal diagnostic test. This study applies KL and further generalizes it to comprehensively measure the diagnostic accuracy test for multi-stage (K > 2) diseases, named generalized total Kullback-Leibler divergence (GTKL). Also, GTKL is proposed as an optimal cut-points selection criterion for discriminating subjects among different disease stages. Moreover, the study investigates a variety of applications of GTKL on measuring the rule-in/out potentials in the single-stage and multi-stage levels. Intensive simulation studies are conducted to compare the performance …


Multiple Imputation Using Influential Exponential Tilting In Case Of Non-Ignorable Missing Data, Kavita Gohil Jan 2020

Multiple Imputation Using Influential Exponential Tilting In Case Of Non-Ignorable Missing Data, Kavita Gohil

Electronic Theses and Dissertations

Modern research strategies rely predominantly on three steps, data collection, data analysis, and inference. In research, if the data is not collected as designed, researchers may face challenges of having incomplete data, especially when it is non-ignorable. These situations affect the subsequent steps of evaluation and make them difficult to perform. Inference with incomplete data is a challenging task in data analysis and clinical trials when missing data related to the condition under the study. Moreover, results obtained from incomplete data are prone to biases. Parameter estimation with non-ignorable missing data is even more challenging to handle and extract useful …


Automated Change Detection In Privacy Policies, Andrick Adhikari Jan 2020

Automated Change Detection In Privacy Policies, Andrick Adhikari

Electronic Theses and Dissertations

Privacy policies notify Internet users about the privacy practices of websites, mobile apps, and other products and services. However, users rarely read them and struggle to understand their contents. Also, the entities that provide these policies are sometimes unmotivated to make them comprehensible. Due to the complicated nature of these documents, it gets even harder for users to understand and take note of any changes of interest or concern when these policies are changed or revised.

With recent development of machine learning and natural language processing, tools that can automatically annotate sentences of policies have been developed. These annotations can …


Controlling Transition Metal-Catalyzed Alkyne Annulations Utilizing Polarized Ynol Ethers, Brandon L. Coles-Taylor Jan 2020

Controlling Transition Metal-Catalyzed Alkyne Annulations Utilizing Polarized Ynol Ethers, Brandon L. Coles-Taylor

Electronic Theses and Dissertations

Transition metal-catalyzed alkyne annulations have developed into incredibly powerful synthetic tools over there the past quarter century. These reactions provide rapid access to important organic scaffolds such as indole, quinoline, isoquinoline, indene, and isocoumarin scaffolds. Transition metal mediated alkyne annulations have proven invaluable in synthetic fields, such as natural product total synthesis, by offering efficient pathways to otherwise synthetically difficult to access substrates.

Foundational works performed by chemist such as Larock, Ackermann, Satoh, and Miura have been established through relying upon the usage of symmetrical alkynes. When unsymmetrical alkynes are used in annulation processes mixtures of regioisomers are often isolated. …


Deep Siamese Neural Networks For Facial Expression Recognition In The Wild, Wassan Hayale Jan 2020

Deep Siamese Neural Networks For Facial Expression Recognition In The Wild, Wassan Hayale

Electronic Theses and Dissertations

The variation of facial images in the wild conditions due to head pose, face illumination, and occlusion can significantly affect the Facial Expression Recognition (FER) performance. Moreover, between subject variation introduced by age, gender, ethnic backgrounds, and identity can also influence the FER performance. This Ph.D. dissertation presents a novel algorithm for end-to-end facial expression recognition, valence and arousal estimation, and visual object matching based on deep Siamese Neural Networks to handle the extreme variation that exists in a facial dataset. In our main Siamese Neural Networks for facial expression recognition, the first network represents the classification framework, where we …


Spatial And Temporal Controls On Streamflow Variability In The San Juan Mountains, Colorado, Christopher Lewis Hancock Jan 2020

Spatial And Temporal Controls On Streamflow Variability In The San Juan Mountains, Colorado, Christopher Lewis Hancock

Electronic Theses and Dissertations

This project characterizes and examines changes to the annual hydroclimatic cycle throughout alpine regions of Colorado with a focus on trends in snowpack and snowmelt hydrology. Datasets analyzed for this research include 79 SNOTEL sites throughout Colorado (24 in the San Juan Mountains) which provide climate metrics for Water Years 1988-2018. Impacts on streamflow are evaluated in the San Juan Region through a network of 11 USGS stream gauges. Correlation matrices and linear regression methods examine the relative controls on the magnitude and timing of discharge, and trend detection using the regional Kendall test quantifies the rate of change within …


The Interplay Between Economic Growth And The Environment: The Case Of China, Christian D. Carpio-Thomas Jan 2020

The Interplay Between Economic Growth And The Environment: The Case Of China, Christian D. Carpio-Thomas

Electronic Theses and Dissertations

Historically, economic development has come at the cost of environmental degradation. Since the 1980s, neoliberalism rooted in neoclassical theory has dominated mainstream economic thought. The result has been a dramatic increase in environmental degradation in favor of economic growth. The neoliberal recommendations toward development are encapsulated in the Washington and post-Washington Consensuses which promote the liberalization of trade and foreign investment as well as a reliance on market mechanisms. Ultimately, the goal of neoliberalism is to generate growth regardless of the impact that it places on the environment. The case of China presents an example of an economy which pursued …


Comprehensive Research Synthesis: An Approach To Mixed Methods Research Syntheses, Lilian Linialy Chimuma Jan 2020

Comprehensive Research Synthesis: An Approach To Mixed Methods Research Syntheses, Lilian Linialy Chimuma

Electronic Theses and Dissertations

Mixed methods research synthesis (MMRS) is an emerging application of both mixed-methods research (MMR) and review research. MMRS promises to comprehensively address intricate contemporary research and evaluation questions given diverse evidence sources (across quantitative, qualitative, and MMR primary studies). The significance of concurrently addressing methodological issues for new research developments is widely noted in the literature. Current efforts attempt to streamline methodological practices along with application of the MMRS approach. Researchers have proposed conceptual frameworks to guide the application and practice of MMRS studies. Despite these efforts, complications and disagreements persist. In response to these concerns, this study developed a …


Development Towards An Ethylene Sensing Artificial Metalloenzyme, Mitchell Lee Ellinwood Jan 2020

Development Towards An Ethylene Sensing Artificial Metalloenzyme, Mitchell Lee Ellinwood

Electronic Theses and Dissertations

Ethylene (ethene) is the essential ripening hormone for climacteric plants, and consequently its detection and quantification is of considerable interest to the horticulture industry. Its detection however is a non-trivial pursuit, traditionally requiring expensive and inaccessible instrumentation that fail to provide in vivo information about ethylene. A ruthenium based fluorescent probe for the selective detection of ethylene has recently been developed, and it was envisioned that this probe could be made biocompatible by encasing it within a protein scaffold making it an artificial metalloenzyme. To this end biotinylated N-heterocyclic carbenes (NHCs) were synthesized, which can be appended onto the ruthenium …


Real-Time Detection Of Demand Manipulation Attacks On A Power Grid, Srinidhi Madabhushi Jan 2020

Real-Time Detection Of Demand Manipulation Attacks On A Power Grid, Srinidhi Madabhushi

Electronic Theses and Dissertations

An increased usage in IoT devices across the globe has posed a threat to the power grid. When an attacker has access to multiple IoT devices within the same geographical location, they can possibly disrupt the power grid by regulating a botnet of high-wattage IoT devices. Based on the time and situation of the attack, an adversary needs access to a fixed number of IoT devices to synchronously switch on/off all of them, resulting in an imbalance between the supply and demand. When the frequency of the power generators drops below a threshold value, it can lead to the generators …


Instrument And Application Development In Saturation Recovery And Rapid Scan Electron Paramagnetic Resonance, Joseph E. Mcpeak Jan 2020

Instrument And Application Development In Saturation Recovery And Rapid Scan Electron Paramagnetic Resonance, Joseph E. Mcpeak

Electronic Theses and Dissertations

Enhanced signal sensitivity by the use of Rapid Scan (RS) electron paramagnetic resonance (EPR), a technique that allows for much faster magnetic field scans than traditional field-swept techniques, has facilitated improved data acquisition for many types of samples. For example, irradiated fingernails for radiation dosimetry have been studied using RS-EPR, which resulted in substantial decreases in detection limits. Samarium-mediated reduction mechanisms in organic synthesis have been investigated by RS-EPR providing evidence for a radical intermediate. Spectra of organic radicals exhibiting both narrow lines and closely spaced hyperfine interactions have been recorded via RS-EPR. Well-resolved spectra can be recorded at a …


Discrepancy Inequalities In Graphs And Their Applications, Adam Purcilly Jan 2020

Discrepancy Inequalities In Graphs And Their Applications, Adam Purcilly

Electronic Theses and Dissertations

Spectral graph theory, which is the use of eigenvalues of matrices associated with graphs, is a modern technique that has expanded our understanding of graphs and their structure. A particularly useful tool in spectral graph theory is the Expander Mixing Lemma, also known as the discrepancy inequality, which bounds the edge distribution between two sets based on the spectral gap. More specifically, it states that a small spectral gap of a graph implies that the edge distribution is close to random. This dissertation uses this tool to study two problems in extremal graph theory, then produces similar discrepancy inequalities based …


How 6-12th Grade Staff Support Students With Depression: A Pilot Study To Develop Measures Of Implicit Associations, Explicit Attitudes And Helping Behavior, Paul M. Thompson Jan 2020

How 6-12th Grade Staff Support Students With Depression: A Pilot Study To Develop Measures Of Implicit Associations, Explicit Attitudes And Helping Behavior, Paul M. Thompson

Electronic Theses and Dissertations

Students with emotional disabilities are disproportionately suspended and expelled in K-12 schools. Attribution theory suggests individuals are less likely to provide assistance to others if they believe the individuals are responsible for their own difficulties. To test attribution theory, this study created new measures of explicit attitudes and implicit associations of licensed 6-12th grade staff regarding students with depression as well as a helping behavior measure of staff toward students with depression. The survey was distributed within a single school district in the western United States. A majority of the sample (N = 52) held a mental health license (60%), …


Sensitivity Of Radical Sam Enzyme Mftc To Molecular Oxygen, Vishnu Govindarajan Jan 2020

Sensitivity Of Radical Sam Enzyme Mftc To Molecular Oxygen, Vishnu Govindarajan

Electronic Theses and Dissertations

MftC is a radical S-adenosyl L-methionine (SAM) enzyme that catalyzes the first step in the production of mycofactocin. It is a ribosomally synthesized post-translationally modified (RiPP) redox cofactor shown to be essential for the survival of bacteria in the Mycobacterium genus in the presence of cholesterol as a carbon source and for the sequestration of ethanol. MftC catalyzes the C – terminal decarboxylation of tyrosine and the subsequent cross-linking of tyrosine to the penultimate valine on the precursor peptide MftA. The product formed out of the reaction is processed into mycofactocin in downstream processes. The bacteria in the Mycobacterium tuberculosis …