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Full-Text Articles in Physical Sciences and Mathematics

The Food Truck Problem, Supply Chains And Extensions Of The Newsvendor Problem, Dennis Quayesam Aug 2021

The Food Truck Problem, Supply Chains And Extensions Of The Newsvendor Problem, Dennis Quayesam

Electronic Theses and Dissertations

Inventory control is important to ensuring sufficient quantities of items are available tomeet demands of customers. The Newsvendor problem is a model used in Operations Research to determine optimal inventory levels for fulfilling future demands. Our study extends the newsvendor problem to a food truck problem. We used simulation to show that the food truck does not reduce to a newsvendor problem if demand depends on exogenous factors such temperature, time etc. We formulate the food truck problem as a multi-product multi-period linear program and found the dual for a single item. We use Discrete Event Simulation to solve the ...


Lexicographic Sensitivity Functions For Nonsmooth Models In Mathematical Biology, Matthew D. Ackley May 2021

Lexicographic Sensitivity Functions For Nonsmooth Models In Mathematical Biology, Matthew D. Ackley

Electronic Theses and Dissertations

Systems of ordinary differential equations (ODEs) may be used to model a wide variety of real-world phenomena in biology and engineering. Classical sensitivity theory is well-established and concerns itself with quantifying the responsiveness of such models to changes in parameter values. By performing a sensitivity analysis, a variety of insights can be gained into a model (and hence, the real-world system that it represents); in particular, the information gained can uncover a system's most important aspects, for use in design, control or optimization of the system. However, while the results of such analysis are desirable, the approach that classical ...


Theranostic Nanoparticles Folic Acid-Carbon Dots-Drug(S) For Cancer, Godwin Kweku Babanyinah May 2021

Theranostic Nanoparticles Folic Acid-Carbon Dots-Drug(S) For Cancer, Godwin Kweku Babanyinah

Electronic Theses and Dissertations

This study aims to prepare theranostic nanoparticles (NPs) that are expected to increase cancer diagnostics and therapeutic efficacy. We prepared the NPs constituting carbon dots (CDs) as an imaging agent, folic acid as a targeting agent, doxorubicin (DOX), or gemcitabine (GEM) as chemotherapy agents. The NPs include noncovalent FA-CDs-DOX, covalent CDs-FA-DOX, and covalent FA-CDs-GEM. Through ultraviolet-visible spectroscopy, fluorescence spectroscopy, and Fourier transform-infrared spectroscopy, the fabrication of these NPs was confirmed. It was discovered that the high drug loading efficiency is the noncovalent series while the high drug loading capacity is the covalent series The in-vitro pH-dependent drug release data indicate ...


Plprepare: A Grammar Checker For Challenging Cases, Jacob Hoyos May 2021

Plprepare: A Grammar Checker For Challenging Cases, Jacob Hoyos

Electronic Theses and Dissertations

This study investigates one of the Polish language’s most arbitrary cases: the genitive masculine inanimate singular. It collects and ranks several guidelines to help language learners discern its proper usage and also introduces a framework to provide detailed feedback regarding arbitrary cases. The study tests this framework by implementing and evaluating a hybrid grammar checker called PLPrepare. PLPrepare performs similarly to other grammar checkers and is able to detect genitive case usages and provide feedback based on a number of error classifications.


Zeta Function Regularization And Its Relationship To Number Theory, Stephen Wang May 2021

Zeta Function Regularization And Its Relationship To Number Theory, Stephen Wang

Electronic Theses and Dissertations

While the "path integral" formulation of quantum mechanics is both highly intuitive and far reaching, the path integrals themselves often fail to converge in the usual sense. Richard Feynman developed regularization as a solution, such that regularized path integrals could be calculated and analyzed within a strictly physics context. Over the past 50 years, mathematicians and physicists have retroactively introduced schemes for achieving mathematical rigor in the study and application of regularized path integrals. One such scheme was introduced in 2007 by the mathematicians Klaus Kirsten and Paul Loya. In this thesis, we reproduce the Kirsten and Loya approach to ...


Constructions & Optimization In Classical Real Analysis Theorems, Abderrahim Elallam May 2021

Constructions & Optimization In Classical Real Analysis Theorems, Abderrahim Elallam

Electronic Theses and Dissertations

This thesis takes a closer look at three fundamental Classical Theorems in Real Analysis. First, for the Bolzano Weierstrass Theorem, we will be interested in constructing a convergent subsequence from a non-convergent bounded sequence. Such a subsequence is guaranteed to exist, but it is often not obvious what it is, e.g., if an = sin n. Next, the H¨older Inequality gives an upper bound, in terms of p ∈ [1,∞], for the the integral of the product of two functions. We will find the value of p that gives the best (smallest) upper-bound, focusing on the Beta and Gamma integrals ...


Investigating The Role Of Charge Separation In Triplet State Formation In Zinc Dipyrrin Photosensitizers, Irene Y. Dzaye May 2021

Investigating The Role Of Charge Separation In Triplet State Formation In Zinc Dipyrrin Photosensitizers, Irene Y. Dzaye

Electronic Theses and Dissertations

About 85% of the world’s energy is derived from non-renewable sources—coal, petroleum, and natural gas. Solar photocatalysis is one way to potentially generate cheap renewable fuels by harnessing energy from the sun using a photosensitizer and converting it into chemical energy. The efficiency of a photosensitizer depends on its capacity to form a prolonged triplet excited state. Zinc dipyrrin complexes have the potential to be efficient sensitizers for reductive photochemistry, but their ability to form long-lived triplet excited states still needs extensive research. The overall aim of this research is to probe the role charge separation plays in ...


Gravel Geology And Muskoxen Paleontology Of A Late Pleistocene Fossil Site In Saltville, Virginia, Nickolas A. Brand May 2021

Gravel Geology And Muskoxen Paleontology Of A Late Pleistocene Fossil Site In Saltville, Virginia, Nickolas A. Brand

Electronic Theses and Dissertations

Two distinct studies within the Saltville Valley of southwestern Virginia revealed insights into local Pleistocene geology and paleontology. A variety of analytical techniques were applied to gravel deposits within the paleontological site of SV-5/7 that revealed this unit is very poorly sorted, has a subangular matrix, and contains significant components of silt and sand in addition to rounded cobbles. These results suggest that rather than being deposited by fluvial processes as previously suggested, these gravels were likely the result of one or many debris flows. Additionally, the identity of fossil muskoxen from Saltville was reassessed using cranial and dental ...


Electrodeposition Of Hydrogen Molybdenum Tungsten Bronze Films And Electrochemical Reduction Of Carbon Dioxide., Mohammad Bajunaid May 2021

Electrodeposition Of Hydrogen Molybdenum Tungsten Bronze Films And Electrochemical Reduction Of Carbon Dioxide., Mohammad Bajunaid

Electronic Theses and Dissertations

The foremost aim for performing this study was to focus on the electrodeposition of mixed hydrogen molybdenum tungsten bronze films, which have the potential for e transfer interactions carrying out the reduction of carbon dioxide. A yellow peroxymolybdic tungstate solution was prepared and used for the electrodeposition of hydrogen molybdenum tungsten bronze films on conductive carbon paper. Electrodeposition was carried out at -2.0 V from 20 - 120 minutes to determine the effect of deposition time on film thickness and CO2 reduction. These films were characterized by X-ray photoelectron spectroscopy. The deposited films served as a working electrode for ...


Examining Summertime Melt And Temperatures In The North Pacific Cordillera, Ingalise Kindstedt May 2021

Examining Summertime Melt And Temperatures In The North Pacific Cordillera, Ingalise Kindstedt

Electronic Theses and Dissertations

Temperature changes in glaciated regions are of immediate concern for estimates of future sea level rise. Alaska and the surrounding region contain over 40 mm of potential sea level rise in its many alpine glaciers, which are experiencing some of the highest rates of mass loss globally. However, records of both past and present temperatures in the region’s alpine sectors are sparse and limited in temporal and spatial extent. Here I examine the application of MODIS land surface temperatures and layers of refrozen melt in ice cores as temperature indicators in the St. Elias and Alaska Ranges. First, I ...


Toward Improving Understanding Of The Structure And Biophysics Of Glycosaminoglycans, Elizabeth K. Whitmore Apr 2021

Toward Improving Understanding Of The Structure And Biophysics Of Glycosaminoglycans, Elizabeth K. Whitmore

Electronic Theses and Dissertations

Glycosaminoglycans (GAGs) are the linear carbohydrate components of proteoglycans (PGs) that mediate PG bioactivities, including signal transduction, tissue morphogenesis, and matrix assembly. To understand GAG function, it is important to understand GAG structure and biophysics at atomic resolution. This is a challenge for existing experimental and computational methods because GAGs are heterogeneous, conformationally complex, and polydisperse, containing up to 200 monosaccharides. Molecular dynamics (MD) simulations come close to overcoming this challenge but are only feasible for short GAG polymers. To address this problem, we developed an algorithm that applies conformations from unbiased all-atom explicit-solvent MD simulations of short GAG polymers ...


Std Prevention: An Educational Intervention For Exotic Dancers, Maria Delurdes Dehoyos Feb 2021

Std Prevention: An Educational Intervention For Exotic Dancers, Maria Delurdes Dehoyos

Electronic Theses and Dissertations

The Centers for Disease Control and prevention reported nearly 2.3 million STD cases diagnosed in 2017, and the number is continuing to rise. San Antonio, Texas, is ranked third in the state of Texas with the highest STD rates and leading in the state with congenital syphilis. There is an increased risk for contracting STDs working in the sex industry. There are little to no studies pertaining to any educational interventions offered to exotic dancers to increase personal knowledge on STDs. This research has focused on an educational intervention offered by a nurse practitioner to exotic dancers in two ...


Therapeutic Immunoglobulin G Surface Mobility Promotes Antibody-Dependent Cellular Phagocytosis By Arp2/3 And Syk Mediated Rearrangement Of Fcγ Receptors, Seongwan Jo Jan 2021

Therapeutic Immunoglobulin G Surface Mobility Promotes Antibody-Dependent Cellular Phagocytosis By Arp2/3 And Syk Mediated Rearrangement Of Fcγ Receptors, Seongwan Jo

Electronic Theses and Dissertations

Therapeutic antibodies are rapidly growing class of drugs for treating cancers and immunological disorders by targeting specific antigens or blocking certain pathway to inhibit the tumor growth. In cancer immunotherapy, it was found that Fcγ receptor (FcγR) in immune cells play an important role in antibody dependent cell toxicity against tumor cells. Therefore, understanding FcγR activation mechanism, which requires ligation with immunoglobulin (IgG), is crucial to enhance potency of therapeutic antibodies. One crucial immune responses triggered upon FcγR ligation with IgG is phagocytosis which indicates clearing targets by engulfment. It is known that FcγRs form microclusters which gets rearranged during ...


Development Of A Probabilistic Multi-Class Model Selection Algorithm For High-Dimensional And Complex Data, Madeline Anne Ausdemore Jan 2021

Development Of A Probabilistic Multi-Class Model Selection Algorithm For High-Dimensional And Complex Data, Madeline Anne Ausdemore

Electronic Theses and Dissertations

The development of quantifiable measures of uncertainty in forensic conclusions has resulted in the debut of several ad-hoc methods for approximating the weight of evidence (WoE). In particular, forensic researchers have attempted to use similarity measures, or scores, to approximate the weight of evidence characterized by highdimensional and complex data. Score-based methods have been proposed to approximate theWoE for numerous evidence types (e.g., fingerprints, handwriting, inks, voice analysis). In general, scorebased methods consider the score as a projection onto the real line. For example, the score-based likelihood ratio evaluates and compares the likelihoods of a score calculated between two ...


The Effects Of Saline Soil On Microbiome And The Isolation Of Root-Associated Microbes To Relieve Salinity Stress, Duncan Jakubowski Jan 2021

The Effects Of Saline Soil On Microbiome And The Isolation Of Root-Associated Microbes To Relieve Salinity Stress, Duncan Jakubowski

Electronic Theses and Dissertations

Increasing levels of salinity in once-viable lands for crop production is a serious and growing problem in the Northern Great Plains. The objectives of this study were to determine the effects of saline soil on the microbial composition of plant roots and bulk soil, to measure metabolic changes in plant roots from saline soil, to determine the viability of root-associated microbes as inoculants to increase stress tolerance in plants, as well as determine the impact of saline soil on nitrogen cycling genes linked to greenhouse gas production. This study hypothesizes that high soil salinity levels have a significant impact on ...


Quantifying The Impacts Of Land Use, Management And Climate Change On Water Resources In Missouri River Basin, Arun Bawa Jan 2021

Quantifying The Impacts Of Land Use, Management And Climate Change On Water Resources In Missouri River Basin, Arun Bawa

Electronic Theses and Dissertations

A location-specific evaluation of hydrological landscape responses concerning past and projected climate and land use land cover (LULC) changes can provide a powerful intellectual basis for developing efficient and profitable agroecosystems, and overcoming uncertain and detrimental consequences of LULC and climate shifts. This dissertation assessed the impacts of land use, management, and climate change on water resources in the Missouri River Basin (MRB) through four specific studies that included: (i) to study the responses of leached nutrient concentrations and soil health to winter rye cover crop (CC) under no-till corn (Zea mays L.)-soybean [Glycine max (L.) Merr.] rotation, (ii ...


Analysis Of Volatile Organic Compounds: Petroleum Emissions And Microbial Degradation, A K M Ahsan Ahmed Jan 2021

Analysis Of Volatile Organic Compounds: Petroleum Emissions And Microbial Degradation, A K M Ahsan Ahmed

Electronic Theses and Dissertations

Volatile organic compounds (VOCs) are abundant in nature and can occur in various forms in a wide variety of sources. Petroleum is one of the major sources of VOCs. Petroleum being the most widely used energy resources of the world, often released to the environment due to emission and leakage or accidental spillage during exploration, transportation and manufacturing. Once released to the environment, petroleum poses a serious threat to the environment due to some of its toxic organic components. Therefore, the analysis of petroleum is critical to understand its effect on the environment and remediation. This dissertation is focused on ...


College Students Conceptions Of Particulate Nature Of Matter And The Impact On Research Instrumentation, Bridget Klutse Jan 2021

College Students Conceptions Of Particulate Nature Of Matter And The Impact On Research Instrumentation, Bridget Klutse

Electronic Theses and Dissertations

No abstract provided.


Lightweight Encryption Based Security Package For Wireless Body Area Network, Sangwon Shin Jan 2021

Lightweight Encryption Based Security Package For Wireless Body Area Network, Sangwon Shin

Electronic Theses and Dissertations

As the demand of individual health monitoring rose, Wireless Body Area Networks (WBAN) are becoming highly distinctive within health applications. Nowadays, WBAN is much easier to access then what it used to be. However, due to WBAN’s limitation, properly sophisticated security protocols do not exist. As WBAN devices deal with sensitive data and could be used as a threat to the owner of the data or their family, securing individual devices is highly important. Despite the importance in securing data, existing WBAN security methods are focused on providing light weight security methods. This led to most security methods for ...


A Study Of Geographic Information System-Based Watershed Processing For Hydrologic Analysis Of Ungauged Watersheds, Philip Adanbe Adalikwu Jan 2021

A Study Of Geographic Information System-Based Watershed Processing For Hydrologic Analysis Of Ungauged Watersheds, Philip Adanbe Adalikwu

Electronic Theses and Dissertations

The increasing application of geographic information system (GIS) technology in watershed modeling makes is necessary to further evaluate its impacts on runoff characteristics as a basis for improved hydrologic analysis in ungauged watersheds. Experts in the field of water resources and hydrology have recommended the practice of subdivision when modeling a watershed, and the use of observed data from hydrologically similar watershed to calibrate and validate an ungauged watershed’s model. However, previous studies have failed to adequately address the issues of watershed heterogeneity, spatial and temporal variability in physical parameters, GIS data resolution issues, including artifacts in automated extraction ...


Bias Of Rank Correlation Under A Mixture Model, Russell Land Jan 2021

Bias Of Rank Correlation Under A Mixture Model, Russell Land

Electronic Theses and Dissertations

This thesis project will analyze the bias in mixture models when contaminated data is present. Specifically, we will analyze the relationship between the bias and the mixing proportion, p, for the rank correlation methods Spearman’s Rho and Kendall’s Tau. We will first look at the history of the two non-parametric rank correlation methods and the sample and population definitions will be introduced. Copulas will be introduced to show a few ways we can define these correlation methods. After that, mixture models will be defined and the main theorem will be stated and proved. As an example, we will ...


Assaying Bacillus Amyloliquefaciens 1ba A=And 1d3 For Utilization Of Petroleum Hydrocarbons And Biosurfactant Production, Pavan Kulkarni Jan 2021

Assaying Bacillus Amyloliquefaciens 1ba A=And 1d3 For Utilization Of Petroleum Hydrocarbons And Biosurfactant Production, Pavan Kulkarni

Electronic Theses and Dissertations

Several Bacillus amyloliquefaciens isolates obtained from wheat residue have been studied as biological agents to control wheat diseases. Notable traits of isolates 1BA and 1D3 include growth with high salt (10% NaCl), at temperatures up to 50°C and over a wide pH range. BIOLOG Gen III plates were used to study and further characterize Bacillus amyloliquefaciens 1BA and 1D3. Both isolates showed tolerance to high salt concentration supporting previous studies. They also grew in the presence of lithium chloride, potassium tellurite, and sodium bromate. Both isolates grew at pH 5, with almost identical carbon source utilization fingerprints. However, D-serine ...


Human Activity Recognition Based On Wearable Flex Sensor And Pulse Sensor, Xiaozhu Jin Jan 2021

Human Activity Recognition Based On Wearable Flex Sensor And Pulse Sensor, Xiaozhu Jin

Electronic Theses and Dissertations

In order to fulfill the needs of everyday monitoring for healthcare and emergency advice, many HAR systems have been designed [1]. Based on the healthcare purpose, these systems can be implanted into an astronaut’s spacesuit to provide necessary life movement monitoring and healthcare suggestions. Most of these systems use acceleration data-based data record as human activity representation [2,3]. But this data attribute approach has a limitation that makes it impossible to be used as an activity monitoring system for astronavigation. Because an accelerometer senses acceleration by distinguishing acceleration data based on the earth’s gravity offset [4], the ...


Fluoride Removal With Augmented Bentonite In Drinking Water And Community Perceptions In Arusha, Tanzania, Kara Okular Dec 2020

Fluoride Removal With Augmented Bentonite In Drinking Water And Community Perceptions In Arusha, Tanzania, Kara Okular

Electronic Theses and Dissertations

High fluoride concentrations in drinking water affect millions of people around the world. The World Health Organization recommended a fluoride concentration in drinking water of ≤ 1.5 mg/L; fluoride above this concentration can cause long-term dental and skeletal fluorosis. Fluoride imparts no taste to water; therefore, people do not realize that they are ingesting high fluoridated water. Researchers sought to develop a material to remove fluoride from drinking water through sorption. Aluminum was used to form a double ionic layer on the bentonite clay surface. Once mixed in contaminated water, a coagulant, ferric sulfate, was used to separate the ...


Control Of Corrosion On Ss316l Using Surface Initiated Polymers, Alexander Rupprecht Dec 2020

Control Of Corrosion On Ss316l Using Surface Initiated Polymers, Alexander Rupprecht

Electronic Theses and Dissertations

Pitting corrosion is arguably one of the most destructive and dangerous forms of corrosion, resulting in damage to structures, the environment, and public health. In addition, damage caused to structures such as bridges, pipelines, and boats, corrosion also has a profound effect on the biomedical community. Implanted metallic devices (i.e., vascular stents and artificial joints) are prone to pitting corrosion caused by aggressive ions present in extracellular fluid. To provide a corrosion-resistant surface on SS316L, films of poly(styrene), poly(methyl acrylate), and poly(methyl methacrylate) were formed using surface-initiated atom transfer radical polymerization (SI-ATRP). The resulting hydrophobic polymer ...


Functionalized Materials From Atom Transfer Radical Processes, Sean Fischer Dec 2020

Functionalized Materials From Atom Transfer Radical Processes, Sean Fischer

Electronic Theses and Dissertations

This work is focused on the synthesis, characterization, and application of functionalized materials prepared from atom transfer radical processes. Atom transfer radical processes encompass both atom transfer radical addition (ATRA) and polymerization (ATRP) reactions, both of which are catalyzed by ppm amounts of copper complexes. The synthetic efforts of ATRA include increasing adduct selectivity through optimization of reaction conditions to generate small molecules in high to moderate yields. ATRA provides retention of the halogen moiety, which is an attractive functional group that can be further modified with other transformations. Specifically, the copper-catalyzed azide-alkyne [3+2] cycloaddition (CuAAC) allows for the ...


Live Cell Super-Resolution Microscopy Quanitifies An Interaction Between Influenza Hemagglutinin And Phosphatidylinositol 4,5-Bisphosphate, Jaqulin N. Wallace Dec 2020

Live Cell Super-Resolution Microscopy Quanitifies An Interaction Between Influenza Hemagglutinin And Phosphatidylinositol 4,5-Bisphosphate, Jaqulin N. Wallace

Electronic Theses and Dissertations

Influenza virus, colloquially known as the flu, is an acute respiratory disease that infects several millions of individuals each year in the U.S. and kills tens of thousands of those infected. Yearly viral vaccines are widely available, however, due to the virus’s high mutation rate, their efficacy varies greatly. Due to the variability in vaccine efficiency against seasonal influenza, and the potential for even more pathogenic versions of influenza to emerge at any time, there is a high demand for a universal treatment option.

Influenza virus hijacks a variety of host cell components in order to replicate. The ...


Understanding Biomass Upgrading Through Hydrogenolysis Reactions: Kinetics And Mechanism, Jalal Tavana Dec 2020

Understanding Biomass Upgrading Through Hydrogenolysis Reactions: Kinetics And Mechanism, Jalal Tavana

Electronic Theses and Dissertations

This dissertation involves several hydrogenolysis reactions but is mainly focused on hydrodechlorination (HDC) of chlorobenzene (PhCl) and hydrodeoxygenation (HDO) of 2-furancarboxylic acid (FCA). Hydrodechlorination of PhCl has been the subject of research for some time. Here, we used a Pd/C catalyst to study this reaction though rigorous kinetics and mechanistic analyses in a CSTR reactor. The H2/D2 kinetic isotope effect (KIE) experiment revealed that H2 is not involved in a rate controlling step. The kinetics data are in agreement with similar systems reported before and follow a first-order dependence on chlorobenzene, half order for hydrogen ...


Species Distribution Modeling For Arid Adapted Habitat Specialists In Zion National Park, Sam Driver, Chris M. Schalk, Daniel Unger, David Kulhavy Dec 2020

Species Distribution Modeling For Arid Adapted Habitat Specialists In Zion National Park, Sam Driver, Chris M. Schalk, Daniel Unger, David Kulhavy

Electronic Theses and Dissertations

The Arizona toad (Anaxyrus microscaphus) and Jones’ waxy dogbane (Cycladenia humilis var. jonesii) are habitat specialists with historical ranges in the desert southwest and specifically, Zion National Park (ZION). The machine learning method, MaxEnt, constructed species distribution models (SDMs) in ZION for the two study species at 30 m and 900 m spatial resolutions using climate, topographic, and remotely sensed data. Additionally, 900 m forecasting models were constructed to observe the shifts in suitable habitat for the years 2050 and 2070, based off two representative concentration pathway scenarios. Results indicate promising predictive power for both high resolution models (30m) for ...


Petrology Of The Gradational Intrusive Contact Between The Packsaddle Schist And The Town Mountain Granite, Enchanted Rock State Natural Area, Llano Uplift, Central Texas, Travis Galle Dec 2020

Petrology Of The Gradational Intrusive Contact Between The Packsaddle Schist And The Town Mountain Granite, Enchanted Rock State Natural Area, Llano Uplift, Central Texas, Travis Galle

Electronic Theses and Dissertations

The Mesoproterozoic intrusive contact between the ~1.1 Ga anorogenic Town Mountain Granite and the ~1.3 Ga Packsaddle Schist is a gradational contact exhumed within the Llano uplift. This contact is exposed along the southeastern margin of the Enchanted Rock batholith in central Texas. Field observations, hand sample and thin section petrography, and handheld X-ray fluorescence analysis of hand samples were used to characterize the gradational nature of this contact at multiple scales. The style of gradation between the Town Mountain Granite and Packsaddle Schist varies throughout the study area, containing both injection and permeation. The complex relationships observed ...