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Antidiabetic Activity Of Cissus Rotundifolia Plant Growing In Saudi Arabia, Saad Ali Alshehri

Electronic Theses and Dissertations

Diabetes mellitus (DM) is a metabolic disease characterized by high levels of blood glucose resulting from defects in insulin production or action. A world-wide increase in the diabetes rate is projected to reach pandemic levels over the next 10-20 years. Current data shows that high numbers of the population in Saudi Arabia suffer from diabetes and prediabetes. Non-traditional treatments of diabetes from medicinal plants has shown potential antidiabetic activity. A considerable percentage of the population still prefer or use medicinal plants as a treatment or supplement to traditional medicine. Cissus rotundifolia (family Vitaceae) is a known plant in southwestern Saudi …

Enhanced Charge Carrier Dynamics And Defects Passivation In Hybrid Perovskite Solar Cell Using A Novel Organic Halide Salt, Md Ashuqur Rahman Laskar

Electronic Theses and Dissertations

In the last few years, active research works on hybrid perovskite solar cells (HPSCs) have been going on throughout the world as a part of clean energy revolution. HPSCs have already proved their potentiality as future solar technology through their promising photovoltaic performances and ability for low temperature based solution processing. Nevertheless, still there are remaining challenges of better charge carrier dynamics and defects minimization in HPSCs. Overcoming these challenges are very important to achieve high power conversion efficiency (PCE) practically. Aiming this, a novel organic halide salt called Phenylhydrazinium Iodide (PHAI) is introduced as additive with CH₃NH …

Implementing And Assessing The Use Of A New Strategy For Training Chemistry Graduate Teaching Assistants, Amanda Hyett

Electronic Theses and Dissertations

Graduate teaching assistants (GTAs) largely contribute to undergraduate education but are often underprepared for their role as educators. Most graduate students attend graduate school to perform research and are then asked to teach for the first time without sufficient pedagogy training. To assist in increasing the GTAs pedagogical knowledge, a scenario-based activity series was developed and implemented for first- and second-year GTAs. Developing scenario-based scenarios from actual laboratory events provided GTAs with the opportunity to practice prior to engaging in the laboratory classroom. The Teaching Assistant Intervention Activities (TAIAs) included topics such as interpersonal skills and behaviors, group process, working …

Epidemiological Investigations Of Bighorn Sheep Respiratory Disease And Implications For Management, Brandi L. Felts

Electronic Theses and Dissertations

Infectious respiratory disease has long been identified as the cause of bighorn sheep (Ovis canadensis) historical declines and extirpations, and Mycoplasma ovipneumoniae (Movi) is the primary pathogen inducing disease and mortality. Population-level effects of pneumonia events range from mild to extirpation. Variable individual response to pathogen exposure emerges from dynamic interactions between competing evolutionary processes within the host and pathogen. Understanding impacts of this evolutionary warfare is essential to assessing long-term impacts of pathogen invasion and developing appropriate countermeasures to protect population health. Freeranging populations are faced with spillover infections from domestic sheep and goats as well as …

Scavenger Hunt: The Search For Sulfur Mustard-Neutralizing Compound In 2-Chloroethyl Ethyl Sulfide (Cees) Treated Human Keratinocyte (Hacat) Epithelial Cells, Tanner Diemer

Electronic Theses and Dissertations

Sulfur mustard is a highly toxic and dangerous vesicant that has been utilized as a chemical warfare agent (CWA) since World War I. Despite its extensive history, an effective antidote to sulfur mustard exposure still does not exist. With detectable levels of unreacted sulfur mustard lasting days after initial contact, a window of opportunity exists to administer a “scavenger” to affected individual immediately and in the days following exposure in hopes of reducing harm by neutralizing unreacted sulfur mustard. For this strategy to be effectively implemented, it is essential to identify a candidate compound with excellent affinity towards sulfur mustard …

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 …

Partitioning Variation In Measurements Of Beef Carcass Traits Made Using Ultrasound, Bradie M. Schmidt

Electronic Theses and Dissertations

Ultrasound technology provides cattle breeders a relatively quick, non-invasive, and economical way to gather carcass data on live animals. Ultrasound provides the means to accurately predict body composition and develop estimated breeding values; however, national cattle genetic evaluations assume homogenous additive genetic and residual variances. These assumptions may be violated when estimating genetic merit for carcass traits by ultrasound because of differences in variance due to scanning technician and image interpretation laboratory. The objective of this study was to partition the phenotypic variance of measurements of carcass traits that were made using ultrasound into components attributable to additive genetic effects, …

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 …

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 (EC_1:1) that …

Exploring The Relationship Between Receipt Of A Mississippi Need-Based State Grant And Grade Point Average Among Graduating Seniors At The University Of Mississippi, Clate A. Holleman

Electronic Theses and Dissertations

This dissertation in practice (DiP) studies the relationship between the receipt of the Mississippi Higher Education Legislative Plan for Needy Students (MS-HELP) Grant and cumulative grade point average (GPA) at the beginning of their graduating term among graduating senior students at the University of Mississippi (UM). This study relies on the metric of Expected Family Contribution (EFC), which is a dollar amount generated by the Free Application for Federal Student Aid (FAFSA) designed to measure the amount of money a household can reasonably be expected to contribute to higher education. The MS-HELP Grant is a need-based grant provided by the …

Novel Ophthalmic Formulations For Improved Natamycin Delivery In Fungal Infections Of The Eye., Akash Vijay Patil

Electronic Theses and Dissertations

Natamycin (NT) is a front-line drug in the management of ocular fungal infections (OFI). An ophthalmic marketed NT suspension (Natacyn®) is currently the only FDA approved medication prescribed in the pharmacotherapy of OFI. Current NT pharmacotherapy requires frequent topical administration (every hour or 2-hours over 6-8 times in a day) due to it being instilled as eye-drops. This leads to higher precorneal losses and subsequent poor permeation and bioavailability. Therefore, in this research study, alternative ocular formulations of NT were investigated with an intent to improve precorneal retention and corneal permeation in comparison to Natacyn®. Chapter 1 discusses various aspects …

Simulation Analysis Of Bluetooth Scanning Systems, George Humphrey

Electronic Theses and Dissertations

We develop and present a simulation program to investigate the failure probability of a scanning job conducted by a Bluetooth Low-Energy scanner on a group of items. Each item is outfitted with a BLE device and are sorted into large, batch sizes to be moved into the scanning area. The BLE device broadcasts packets, known as advertisements, to the scanning system. The rate at which the advertisements broadcast is determined by its interadvertisement time, which is the sum between a fixed advertising interval and a pseudo-random advertising delay. The objective is to determine the optimal interadvertisement time that minimizes the …

Acoustic Modeling Of A Uas For Use In A Hostile Fire Detection System, Keegan Kurpakus

Electronic Theses and Dissertations

Unmanned Aerial System (UAS) usage has continually increased in recent years for both recreational and military applications. One particular military application being researched is utilizing a UAS as a host platform for Hostile Fire Detection Systems (HFDS), with particular interest being focused on multi-rotor drone platforms. The type of HFDS considered in this work is based upon acoustic sensors. An acoustic based HFDS utilizes an array of microphones to measure acoustic data and then applies signal processing algorithms to determine if a transient signal is present and if present then estimates the direction from which the sound arrived. The main …

Admission Officers' Perceptions Of Implicit Bias In The Admission Process, Christi Denise Hardy

Electronic Theses and Dissertations

Although they are not involved in the decision making process, admission officers at institutions of higher learning could have a significant effect on the admission process. For the purposes of this research, admission officers are defined as the primary personnel assisting applicants to complete their applications through the collection of applications, fees, essays, transcripts, test scores, and other supplemental documents required by the institution for admission consideration. More specifically, their implicit biases could significantly affect the admission process. Research on implicit biases is on the rise, and studies investigating this issue in health care and hiring practices are abundant. Implicit …

Topics In Analytic And Combinatorial Number Theory, Zhenchao Ge

Electronic Theses and Dissertations

In this dissertation, I introduce some results that I have proved (collaboratively and independently) in analytic number theory and additive combinatorics. In analytic number theory, I study certain continuous and discrete mean value estimates for the Z-function associated to a Dirichlet L-functions. These problems lead naturally to an investigation of certain Gauss type sums which are studied in some depth. This is joint work with Jonathan W. Bober and Micah B. Milinovich. In additive combinatorics, I study two problems on sumsets. This is joint work with Thai Hoang Le.

Application Of Fluorinated Reagents In Synthesis And Drug Discovery, Amna T. Adam

Electronic Theses and Dissertations

ABSTRACT The introduction of fluorine or fluorine containing moieties in pharmaceuticals may increase metabolic stability, binding affinity, bioavailability, lipophilicity, selectivity for targets, and fluorine-labelled groups can be used as imagining probes, i.e. in positron emission tomography (PET). Within the past decade, approximately 20% of all marketed pharmaceuticals contain fluorine and in 2018 alone 36% of the top 50 selling drugs on the market contained one or more fluorine atoms. Fluorinated reagents also plays an important role in the development of methods to introduce unique groups into an organic molecule, such as fluorination and methylenation. In this work, the scope of …

Development Of An Ophthalmic Nanoemulsion Topical Formulation For Corneal Wound Healing, Chuntian Cai

Electronic Theses and Dissertations

Corneal wound healing is a complex process involving cell death, migration, proliferation, differentiation, extracellular matrix remodeling and a various of growth factors. Of these factors, interleukin-1 and transforming growth factor beta allow the effectiveness of cell migration and tissue repair. Current management advocates multiple therapies aimed to prevent inflammation, avoid the fibrosis. Pirfenidone (PFD) has recently been investigated for its anti-fibrotic effect. The current study was undertaken to develop and optimize PFD-loaded nanoemulsion (NE; PFD-NE) which could increase the drug load and the duration of activity. Hot homogenization and probe sonication methods were used for the preparation of PFD-NEs, sesame …

In Planta Evaluation Of Gene Regulation By Soybean Auxin Response Factors, Pratiksha K C

Electronic Theses and Dissertations

Nitrogen (N) is an important plant nutrient but its abundance in the soil is not sufficient for profitable crop production. N input in the form of chemical fertilizers helps fill this need; however, an alternative for fertilizers is an immediate need due to the environmental pollution resulting from excessive use of fertilizers. Leguminous plants such as soybean (Glycine max) that form root nodules through symbiotic association with N-fixing rhizobia and therefore need little or no chemical N fertilizers. The plant hormone auxin plays a crucial role in determining the number of nodules and their rate of maturity in soybean. Auxin …

Resonant Ultrasound Spectroscopy Studies Of Poroelasticity In Porous Ceramics And Elasticity Of Thermoelectric Snse, Ashoka Karunarathne

Electronic Theses and Dissertations

This dissertation primarily focuses on use of resonant ultrasound spectroscopic (RUS) measurements to investigate temperature- and pressure-dependent elastic properties of select materials: porous ceramics, which are used in a wide range of material applications, and thermoelectric tin selenide (SnSe), which is widely studied as an efficient thermoelectric material. RUS experiments were conducted on: ceramics used in LG fuel cells, alumina, zircona and titania, to explore their elastic behavior under the variation of hydrostatic pressure over the low- and high-pressure regimes (0.02 – 800 psi). All the porous ceramics exhibited a reversible material softening mechanism with increasing hydrostatic pressure. The comparison …

Determining The Effectiveness Of Rock Mass Classification Schemes When Used To Derive Empirical Predictions For Rock Mass Deformation Modulus, Tanner Cecil Avery

Electronic Theses and Dissertations

Normal deformation modulus of rock masses (Erm) is a critical design parameter for any permanent excavation and infrastructure project that requires limited or controlled deformations to ensure performance of permanent support systems and of foundations. Despite being a key parameter, the optimal methods for determining Erm is still debated. These methods can be put into three categories: in-situ tests, empirical solutions, and numerical solutions. Current efforts to derive empirical predictions rely on rock mass classification schemes (RMCS) with the assumption that all RMCS are similarly effective at predicting Erm. Since different RMCS use different sets of variables this assumption does …

Mississippi Teachers Who Are Nationally Board Certified Or Those With Advanced Degrees: Effects On Student Achievement, Amy Tate Barnett

Electronic Theses and Dissertations

The purpose of this research study was to determine the interaction effects national board certified teachers (NBCTs) and teachers with advanced degrees (ADs); while considering school accountability levels, had on student achievement. This study examined whether significant differences existed in student achievement between the eight identified groups of teachers and how the factors of NBCT status, AD status, and accountability contributed. The study examined student achievement in grades three through eight on the end-of-the-year state assessments for the 2017-18 school year. This research endeavor relied upon the recruitment of local Mississippi school districts and their willingness to participate and share …

Effective Response To Intervention In Middle School, Angela Mechelle Ellison

Electronic Theses and Dissertations

This applied mixed methods program evaluation sought to increase student proficiency in mathematics at a rural middle school in central Mississippi. The program focused on improving student achievement through effective professional development. Quantitative and qualitative data was used to gage the program’s effectiveness. Research supporting an effective Response to Intervention Model, professional learning communities, and teacher development was cited and used to construct the program’s implementation framework.

Differential Semantics, William Michael Cox

Electronic Theses and Dissertations

Differential Semantics is a theoretical accounting of the semantic complexity found in natural language, particularly that of the academic and literary registers. It addresses natural language semantics in terms of its contribution to the characterization and expression of creative thought, beginning the perception and conceptualization of objective reality, folloby the metacognitive development of idiosemantic connotations in reference to those conceptualizations, and finally, the intuitive process of implication and inference that facilitates the abstraction and communication of thought.

Aproaches To Develop Acyclovir Gastro-Retentive Formulations Using Hot Melt Extrusion Technology, Peilun Zhang

Electronic Theses and Dissertations

The aim of the current study was to prepare and compare acyclovir (ACV) floating gastro-retentive formulations synthesized via hot-melt extrusion (HME) techniques using P-CO2 and sodium bicarbonate. Physical mixtures of ACV (20%, w/w) and HPC EF (70%, 60%, w/w) with HPC MF (10%, w/w) or HPMCAS-LG (10%, w/w) were prepared using a co-rotating twin-screw extruder with a screw configuration shoin Figure 2. P-CO2 was injected into zone 9 of the extruder or NaHCO3 was added (10% w/w) during the extrusion process. In vitro dissolution studies (0.1 N hydrochloric acid medium) demonstrated that the formulations floated on the medium because of …

Diversifying The Pipeline: Barriers That Prevent Teachers Of Color From Entering The Profession, Erica L. Avent

Electronic Theses and Dissertations

Every year the number of certified teachers entering the teacher workforce is declining across the nation. This decline affects districts across the country, but it especially affects the students that these districts serve. While there is a decline in teachers overall, there is a severe decline in African American teachers. Non- Caucasian students are the largest demographic of students that attend public schools (Cherng & Halpin, 2016). In 2001, forty percent of the students in public education identified as a student of color (Ladson-Billings, 2005a). At the same time, only twelve percent of teachers were non-Caucasian. For those diverse students …

An Analysis Of Efl Learners’ Foreign Language Anxiety And Their Motivation To Learn English, Maide Beyza Cayli

Electronic Theses and Dissertations

This thesis aims to investigate English-language learners’ foreign language anxiety and their motivations to learn English in an American context. The adapted versions of The Motivation/Attitude Questionnaire (Ozturk 2012), and Foreign Language Anxiety Scale (Horwitz et al 1986) were given to 34 Intensive English Program students at a college in Southeastern United States. The participants in the Advanced and Advanced Plus Level have shown moderate level of Foreign Language Anxiety and Motivation. The results have prevailed that the students with higher proficiency levels have had slightly higher level of motivation. Yet, the participants with a higher level of English proficiency …

2d Confinement Of Thermal Gradients In Metallic Non-Local Spin Valves, Rachel K. Bennet

Electronic Theses and Dissertations

Non-local spin valves (NLSVs) are a valuable tool in the growing field of spintronics due to their unique ability to separate charge current from pure spin current. Their potential applications as read heads for hard-disk drives, as well as use as logic gates and other spin sensors, makes detailed understanding of their behavior under a wide range of operating conditions very important.

In this dissertation, I present results of extreme thermal engineering of the supporting substrate of NLSVs, which has a dramatic impact on the background signal of the device as well as contributions from thermal spin effects such as …

Satellite Constellation Deployment And Management, Joseph Ryan Kopacz

Electronic Theses and Dissertations

This paper will review results and discuss a new method to address the deployment and management of a satellite constellation. The first two chapters will explorer the use of small satellites, and some of the advances in technology that have enabled small spacecraft to maintain modern performance requirements in incredibly small packages.

The third chapter will address the multiple-objective optimization problem for a global persistent coverage constellation of communications spacecraft in Low Earth Orbit. A genetic algorithm was implemented in MATLAB to explore the design space – 288 trillion possibilities – utilizing the Satellite Tool Kit (STK) software developers kit. …

Actin Regulation And Furrow Dynamics During Early Drosophila Embryogenesis, Yi Xie

Electronic Theses and Dissertations

Drosophila embryogenesis starts with a single nucleus undergo 13 rounds of nuclear divisions called syncytial cycles. Staring at cycle 10 when nuclei migrate to the surface of the embryo, massive and dynamic cortical actin structures and cleavage furrow formations occur. How actin regulators coordinate into an organized network directing three-dimension actin structures in the developing organisms is an unsolved question. Here, I present an in-depth characterization of actin cap dynamics: the actin caps go through expansion, stabilization, elongation and fragmentation phases in each cycle. Arp2/3 is the major contributor to actin cap formation. The functions of 7 different actin and …

Human Genetics, Psychotropic Drugs, And Acts Of Violence, Selma Jolanda Eikelenboom-Schieveld

Electronic Theses and Dissertations

From the start of the use of psychoactive prescription medications in the 1950s, physicians reported paradoxical adverse reactions, ranging from newly developing depressions to an increase in existing mood disorders, and extremely violent and bizarre acts of suicide and homicide. In this research, it is hypothesized that the pharmacological properties of the prescribed drugs or the interaction between the drugs and the enzymes that are primarily responsible for their metabolism (cytochrome P450s) could cause these reactions. Given that acts of violence could be medication-induced, the role of the rate of drug metabolism is discussed. Genetic testing of certain CYP450s could …