Optical Properties And Simulated X-Ray Near Edge Spectra For Y2o2s And Er Doped Y2o2s, Nicholas Dimakis, Eric Baldemar Rodriguez Jr., Kofi Nketia Ackaah-Gyasi, Madhab Pokhrel

Physics & Astronomy Faculty Publications

The electronic and optical properties of Y2O2S and its Er+3 doped counterparts at various concentrations are analyzed using density functional theory (DFT) and simulated x-ray near edge (XANES) spectra. Our simulations are complemented by absorption experiments, which show Y2O2S:Er+3 light emissions in the visible and near infrared. These emissions correspond to Er f–f intraband transitions. We use DFT and DFT+U to calculate the band structure of the Y2O2S and its Er+3 doped counterparts, whereas optical properties are calculated using the independent particle approximation (IPA). The host Y2O2S optical properties are also calculated using the random phase approximation (RPA) and …

Non-Hermitian Skin Effect In Two Dimensional Continuous Systems, Cem Yuce, Hamidreza Ramezani

Physics & Astronomy Faculty Publications

An extensive number of the eigenstates can become exponentially localized at one boundary of nonreciprocal non-Hermitian systems. This effect is known as the non-Hermitian skin effect and has been studied mostly in tight-binding lattices. To extend the skin effect to continues systems beyond 1D, we introduce a quadratic imaginary vector potential in the continuous two dimensional Schr¨odinger equation. We find that inseparable eigenfunctions for separable nonreciprocal Hamiltonians appear under infinite boundary conditions. Introducing boundaries destroy them and hence they can only be used as quasistationary states in practice. We show that all eigenstates can be clustered at the point where …

Phenylboronic Ester-Modified Polymeric Nanoparticles For Promoting Trp2 Peptide Antigen Delivery In Cancer Immunotherapy, Qiyan Wang, Zhipeng Dong, Fangning Lou, Yunxue Yin, Jiahao Zhang, Hanning Wen, Tao Lu, Yue Wang

Dermatology Articles

The tremendous development of peptide-based cancer vaccine has attracted incremental interest as a powerful approach in cancer management, prevention and treatment. As successful as tumor vaccine has been, major challenges associated with achieving efficient immune response against cancer are (1) drainage to and retention in lymph nodes; (2) uptake by dendritic cells (DCs); (3) activation of DCs. In order to overcome these barriers, here we construct PBE-modified TRP2 nanovaccine, which comprises TRP2 peptide tumor antigen and diblock copolymer PEG-b-PAsp grafted with phenylboronic ester (PBE). We confirmed that this TRP2 nanovaccine can be effectively trapped into lymph node, uptake by dendritic …

Quantifying The Magnitude Of To Tal Dose Deviation Caused By Various Sources Of Error Among Iroc Phantom Irradiation Results, Sharbacha S. Edward

Dissertations and Theses (Open Access)

The Imaging and Radiation Oncology Core (IROC) phantoms are used as an end-to-end test of an institution’s radiotherapy processes, and for clinical trial credentialing. Phantoms are treated like patients, and evaluation of the doses received by the thermoluminescent dosimeters (TLDs) inside the phantom, reflects the accuracy with which an institution can image, plan and irradiate a phantom or patient. Recent phantom results show that among the hundreds of various IROC phantoms irradiated annually, 8-17% of institutions fail this test. The purpose of this work was to investigate the various types of errors that may occur during the treatment process and …

Bayesian Adaptive Clinical Trial Design, Mengyi Lu

Dissertations and Theses (Open Access)

The landscape of drug development in oncology has changed from conventional chemotherapies to molecular targeted therapies and immunotherapies, which provide innovative therapeutic modalities for treating cancers. These novel therapeutic agents work through mechanisms that fundamentally differ from standard chemotherapeutic agents, making the conventional trial design paradigm inefficient and dysfunctional. Specifically, the focus of dose-finding trials has shifted from finding the maximum tolerated dose (MTD) to the optimal biological dose (OBD), defined as the dose that optimizes the risk–benefit tradeoff. How to accurately identify the OBD and its dosing schedule is of great importance to maximize efficacy and safety of targeted …

Infrastructure Development For Personalized Risk Prediction To Reduce Cardiovascular Disease In Childhood Cancer Survivors, Suman Shrestha

Dissertations and Theses (Open Access)

Although childhood cancer survivors have lengthy life expectancies, they run the risk of experiencing long-term health issues as a result of their treatment. The most frequent non-cancerous cause of morbidity and mortality for these survivors is cardiac disease. Radiation therapy (RT) has been linked in numerous cohort studies to a higher chance of developing a late cardiac disease in these survivors, and this risk rises with higher mean heart doses and increased RT exposure to larger cardiac volumes. Since, the heart is a heterogeneous organ made up of several distinct substructures, RT dose received by the entire heart does not …

Irreducible Representations From Group Actions On Trees, Charlie Liou

Master's Theses

We study the representations of the symmetric group $S_n$ found by acting on

labeled graphs and trees with $n$ vertices. Our main results provide

combinatorial interpretations that give the number of times the irreducible

representations associated with the integer partitions $(n)$ and $(1^n)$ appear

in the representations. We describe a new sign

reversing involution with fixed points that provide a combinatorial

interpretation for the number of times the irreducible associated with the

integer partition $(n-1, 1)$ appears in the representations.

The Relationships Between College And Career Readiness Assessments, Charlotte M. Bruner

All Dissertations

This study explored the effects of taking Advanced Placement (AP) courses on college and career readiness in a rural school district in the southeastern United States. I examined student performance data using American College Test (ACT) scores, Ready to Work (R2W) examination scores, and AP examination scores. The results of the study show that taking a single AP course leads to significant improvement on the ACT exam over a student who has not taken an AP courses and the optimal number of courses a student should take. The results of the study also show that taking an AP course leads …

High-Performance Vlsi Architectures For Lattice-Based Cryptography, Weihang Tan

All Dissertations

Lattice-based cryptography is a cryptographic primitive built upon the hard problems on point lattices. Cryptosystems relying on lattice-based cryptography have attracted huge attention in the last decade since they have post-quantum-resistant security and the remarkable construction of the algorithm. In particular, homomorphic encryption (HE) and post-quantum cryptography (PQC) are the two main applications of lattice-based cryptography. Meanwhile, the efficient hardware implementations for these advanced cryptography schemes are demanding to achieve a high-performance implementation.

This dissertation aims to investigate the novel and high-performance very large-scale integration (VLSI) architectures for lattice-based cryptography, including the HE and PQC schemes. This dissertation first presents …

Increasing Classroom Teachers' Use Of Linguistically Responsive Strategies To Support English Language Learners: A Mixed-Methods Study, Christie Shealy

All Dissertations

With the dawn of the new decade, English Language Learner (ELL) populations began to grow in states without structures and professional learning to equip teachers to face the changing demographic of the classroom. In response to the growth of the knowledge gap between classroom teachers in South Carolina and their diverse classrooms, I conducted a study based on improvement science principles. As a long-standing ELL program coordinator, I experienced the need to increase linguistic responsiveness in classroom teachers on a daily basis. The application of the plan-do-study-act (PDSA) cycle utilized mixed methodology to gather data to increase classroom teachers’ use …

Data-Driven Biomarker Panel Discovery In Ovarian Cancer Using Heterogenous Data Fusion On Exosomal And Non-Exosomal Microrna Expression Data, Paritra Mandal

All Dissertations

Ovarian cancer (OC) is an aggressive gynecological cancer and is currently the 5th leading cause of deaths due to cancer in women. High mortality rates are attributable to the vague pathogenesis and asymptomatic nature of the early stages. The development of a liquid biopsy for routine OC screening could help identify the disease at an earlier stage, making treatments more likely to be effective thereby increasing survival rates. Exosomes, small (~100nm) extracellular vesicles present in body fluids, have been shown to contain cancer-progression, onset, and related factors, making them good candidates for use in liquid biopsies. However, to date, only …

Behavioral Ecology Of The American Alligator (Alligator Mississippiensis) In Human-Dominated Landscapes Of Coastal South Carolina, Anjelika Kidd-Weaver

All Dissertations

When wildlife habitat is developed to accommodate growing human populations, wildlife are forced to move to undisturbed landscapes or to acclimate to a novel, anthropogenic environment. In this dissertation, we investigated the behavior and ecology of the American alligator (Alligator mississippiensis) in coastal, residential resort communities with an overarching goal of identifying behavioral patterns of alligators that can inform risk management strategies. In Chapter One, we compared the space use of male and female alligators in primarily wetland versus residential landscapes across three seasons to determine if and how space use behaviors of alligators differ. We found that …

Essays On Perioperative Services Problems In Healthcare, Amogh S. Bhosekar

All Dissertations

One of the critical challenges in healthcare operations management is to efficiently utilize the expensive resources needed while maintaining the quality of care provided. Simulation and optimization methods can be effectively used to provide better healthcare services. This can be achieved by developing models to minimize patient waiting times, minimize healthcare supply chain and logistics costs, and maximize access. In this proposal, we study some of the important problems in healthcare operations management. More specifically, we focus on perioperative services and study scheduling of operating rooms (ORs) and management of necessary resources such as staff, equipment, and surgical instruments. We …

On Variants Of Sliding And Frank-Wolfe Type Methods And Their Applications In Video Co-Localization, Seyed Hamid Nazari

All Dissertations

In this dissertation, our main focus is to design and analyze first-order methods for computing approximate solutions to convex, smooth optimization problems over certain feasible sets. Specifically, our goal in this dissertation is to explore some variants of sliding and Frank-Wolfe (FW) type algorithms, analyze their convergence complexity, and examine their performance in numerical experiments. We achieve three accomplishments in our research results throughout this dissertation. First, we incorporate a linesearch technique to a well-known projection-free sliding algorithm, namely the conditional gradient sliding (CGS) method. Our proposed algorithm, called the conditional gradient sliding with linesearch (CGSls), does not require the …

Enhancing The Performance Of Poly(3-Hexylthiophene) Based Organic Thin-Film Transistors Using An Interface Engineering Method, Eyob Negussie Tarekegn

All Dissertations

An original design and photolithographic fabrication process for poly(3-hexylthiophene-2, 5-diyl) (P3HT) based organic thin-film transistors (OTFTs) is presented. The structure of the transistors was based on the bottom gate bottom contact OTFT. The fabrication process was efficient, cost-effective, and relatively straightforward to implement. Current–voltage (I-V) measurements were performed to characterize the primary electronic properties of the transistors. The measured mobility of these transistors was significantly higher than most results reported in the literature for other similar bottom gate bottom contact P3HT OTFTs. The higher mobility is explained primarily by the effectiveness of the fabrication process in keeping the interfacial layers …

Permanently-Installed Distributed Pressure Sensors For Downhole Applications, Xuran Zhu

All Dissertations

Technology advancements (e.g., hydraulic fracturing and horizontal drilling) to recover unconventional oil and gas (UOG) resources are critical in maintaining future U.S. oil and gas production levels. Permanently installed distributed downhole pressure sensors could monitor fracture propagation, assess the effectiveness of hydraulic fracturing, and optimize hydraulic fracturing placement so that overall UOG recovery efficiency can be increased. However, the harsh environment (high temperatures, high pressures, strong vibration, and presence of brine, mud, debris, hydrate, and various gases), the long data telemetry distance, and the requirements of reliability and service lifetime make the downhole monitoring a very challenging task. To combat …

Ligand-Promoted Dissolution Of Uranyl Phosphate Across Scales, Brennan Ferguson

All Dissertations

The formation of uranyl phosphate precipitate is a remediation strategy because the low solubility of uranyl phosphate minerals, like chernikovite, limits the mobility of uranium in contaminated soils. However, organic ligands can complex with aqueous metal cations to form more soluble species. For example, citrate is a commonly occurring organic ligand produced by plants and microbes that increases the solubility of uranium and therefore the dissolution of uranyl phosphate minerals in the uranyl phosphate-citrate system. This effect is an important control on the mobility of uranium in organic-rich, and near-surface vegetated environments. Nevertheless, key aspects of the citrate-uranyl phosphate system …

Machine Learning Solutions For Biomedical Applications, Madeleine St. Ville

All Dissertations

This dissertation proposes three novel Bayesian modeling techniques to addresses the challenges arising from the complex, underlying features of biomedical data. These models are motivated by three different biomedical studies. The first is an analysis of data collected from six efficacy and safety clinical trials of buprenorphine maintenance treatment for opioid use disorder. The focus of this study is to overcome the problem of non-adherence by trial participants that, if left unaccounted for, obscures the true effect of buprenorphine on illicit opioid use. The second study is the assessment of hemodialysis cannulation skill through the use of a sensor-based simulator …

Multi-Criteria Performance Evaluation And Control In Power And Energy Systems, Payam Ramezani Badr

All Dissertations

The role of intuition and human preferences are often overlooked in autonomous control of power and energy systems. However, the growing operational diversity of many systems such as microgrids, electric/hybrid-electric vehicles and maritime vessels has created a need for more flexible control and optimization methods. In order to develop such flexible control methods, the role of human decision makers and their desired performance metrics must be studied in power and energy systems. This dissertation investigates the concept of multi-criteria decision making as a gateway to integrate human decision makers and their opinions into complex mathematical control laws. There are two …

Statistical Methods For Modern Threats, Brandon Lumsden

All Dissertations

More than ever before, technology is evolving at a rapid pace across the broad spectrum of biological sciences. As data collection becomes more precise, efficient, and standardized, a demand for appropriate statistical modeling grows as well. Throughout this dissertation, we examine a variety of new age data arising from modern technology of the 21st century. We begin by employing a suite of existing statistical techniques to address research questions surrounding three medical conditions presenting in public health sciences. Here we describe the techniques used, including generalized linear models and longitudinal models, and we summarize the significant associations identified between research …

Estimation Of Disaggregated Import Demand Functions For Nigeria, Chekwube V. Madichie, Uche C. Nwogwugwu, Franklin N. Ngwu, Olisaemeka D. Mauka

CBN Journal of Applied Statistics (JAS)

This paper estimates disaggregated import demand function for Nigeria using annual data from 1970 to 2019. The study employs the Zivot-Andrews unit root and Gregory-Hansen cointegration tests to account for the role of structural breaks and the error correction mechanism for shortrun analysis, respectively. The results show that household consumption, industrial output and domestic investment are the major determinants of import demand for consumer, intermediate and investment goods, respectively. Furthermore, the import demand for investment goods is not sensitive to variations in relative prices. However, relative prices is negative and significant to import demand for consumer and intermediate goods. Exchange …

Size And Determinants Of The Shadow Economy In Nigeria: Evidence From A Monetary Approach, Tari M. Karimo, Mohammed M. Tumala, Ibrahim U, Wambai

CBN Journal of Applied Statistics (JAS)

Thiis study investigates the size and determinants of the shadow economy in Nigeria. It adopts an aggregation approach within the monetary framework and utilises the ARDL estimation technique to analyse quarterly data from 2010 Q1 to 2019 Q4. On average, the results suggest that the quarterly size of the shadow economy is about 55 per cent of the country’s GDP. The findings show that government size reduces the size of the shadow economy in the short run but increases it in the long run. The study also finds that interest rate, which is the opportunity cost of holding cash, and …

Fiscal And Monetary Policy Interactions In A Developing Economy: A Dsge-Based Evidence From Nigeria, Queen E. Oye, Philip O. Alege

CBN Journal of Applied Statistics (JAS)

This study characterizes the nature of fiscal-monetary interaction in Nigeria and gauges its macroeconomic effects by estimating a New Keynesian Dynamic Stochastic General Equilibrium (NK DSGE) model. Two policy simulations were also conducted. The first experiment considers the desirable active-passive policy mix while the second experiment ranks alternative monetary policy rules among the differing objectives of price, output and exchange rate stabilization. The study finds that fiscal and monetary policies interact as complements in an active monetary and passive fiscal policy mix over the sample period. The result from the first policy simulation reveals that the active monetary and passive …

Market Risk Factors And Stock Returns In The Nigerian Bourse, Omorose A. Ogiemudia, Osagie Osifo, Igbinovia L. Eghosa

CBN Journal of Applied Statistics (JAS)

This study examines the link between market risk and equity return in Nigeria between 1980 to 2019. It employs the vector error correction model (VECM) to determine the short run dynamics and long run effect of market risk factors on stock return. The findings revealed that a dynamic relationship exists between market risk factors and stock returns in Nigeria. Also, exchange rate risk and oil price risks have significant influence on stock return, while inflation and interest rate risk, and political instability risks have a non-significant impact on stock return. Finally, a unidirectional relationship was detected between interest rate, oil …

Savings-Investment Gap In Sub-Saharan Africa: Does The Interaction Of Financial Sector Development And Migrant Remittances Matter?, Wasiu Adekunle, Oluwatosin Adeniyi, Joshua Afolabi, Musibau Babatunde, Edward Omiwale

CBN Journal of Applied Statistics (JAS)

This study analyses the interactive effects of migrant remittances and financial development on savings-investment gap for a panel of 18 Sub-Saharan Africa (SSA) countries from 1990-2017. Results from a panel ARDL model show that migrant remittances reduce savings-investment gap in the long run. The gap is further reduced when the individual effect of financial development, and the interactive effects of migrant remittances and financial development are taken into consideration. Further analysis reveals evidence of widening effects of rising real GDP growth and bank deposits over a long-term horizon, while higher private sector credit widened the savings-investment gap only in the …

Impact Of Exchange Rate On Trade Flow In Nigeria, Victor U. Ijirshar, Isa J. Okpe, Jerome T. Andohol

CBN Journal of Applied Statistics (JAS)

This study examines the impact of exchange rate on trade flow in Nigeria from 1986 to 2021. The study utilises linear and nonlinear autoregressive distributed lag (ARDL and NARDL) models to test the J-Curve hypothesis and the Marshall-Lerner condition in Nigeria. The study found symmetric effects of exchange rate on trade balance, exports, and imports. The findings also show that real exchange rate depreciation has a strong negative influence on trade balance and exports in the short run but positive in the long run, exhibiting the shape typology of the J-curve. Furthermore, the study reveals evidence of the Marshall-Lerner condition …

South Texas Wildlife Activity Across A Fragmented Landscape And Road Mitigation Corridor, Caitlin K. Brett

Theses and Dissertations

Wildlife crossing structures (WCS) and roadside fencing are commonly installed to mitigate habitat fragmentation, wildlife road mortalities, and other negative effects that roads can have on the surrounding landscape. Eight such WCS were constructed below Farm-to-Market (FM)106 in Cameron County, Texas, across a 16 km corridor transecting the Laguna Atascosa National Wildlife Refuge. These WCS, paired with adjacent roadside fencing, were intended to prevent road mortalities of the endangered ocelot (Leopardus pardalis) and to mitigate the barrier effect of FM106 on this and other meso-mammal species. This study will analyze camera trap data from roadside and habitat reference …

Navigating Through A Pandemic (The Unknown): The Effects Of Synchronous Learning For Online And In Person Students On Achievement Scores In Reading And Math In A Private Catholic School In South Texas, Israel Martinez Jr.

Theses and Dissertations

In the Spring of 2020, a wide world pandemic, specifically COVID-19, slammed the door on what we defined as normal life. COVID-19 and its associated pandemic exposed more explicitly great inequities such as access to devices, platforms, and/or places to do schoolwork outside schools in education systems (Fullan, 2020). It also interrupted international travel, it devastated economic growth, and it disrupted schooling globally (Harris & Jones, 2020). In the Summer of 2020, a Catholic school in South Texas set a plan in place to provide a 100% synchronous way of learning for students in elementary grades 1 through 8 to …

Grapefruit Peel Biochar Applications For Immobilizing Copper And Lead In Soil, Michael Alfredo Navarro

Theses and Dissertations

This study investigated the efficacy of grapefruit peel (GP) derived biochar materials (two pyrolysis temperatures 450°C and 800°C) as a potential adsorbent to immobilize heavy metal (copper and lead) in a local sandy loam clay soil. A batch adsorption test with heavy metal concentrations at 50 mg L-1, and 100 mg L-1 revealed that soil itself had the highest immobilization percentage compared to the GP biochars. A soil column experiment was conducted to determine how much the GP biochar samples and the tested soil will exhibit adsorptive characteristics for heavy metals when 50 ml of 50 mg L-1 copper or …

Synthesis Of Bioactive Heterocycles, Shaila Akter Shetu

Theses and Dissertations

The Discovery of a variety of heterocyclic drugs for the treatment of cancer and other diseases (e.g, neglected tropical diseases) is a medical breakthrough and inspiring for the research community as a whole. A wide range of natural, semi-synthetic, and synthetic anticancer drugs are synthesized using various methods. Among them, β -lactams stand out as a novel class of antibiotics that has different types of biological as well as anti-cancer properties. β -lactam has become a premier and active research subject towards the development of revolutionary anti-cancer drugs. In recent years, a large amount of investigations have been done to …