Physical Sciences and Mathematics Commons^™

Kudzu Invasion And Control In Southern Upland Forests Of Mississippi, Gina M. Profetto

University of New Orleans Theses and Dissertations

Kudzu, Pueraria montana var. lobata (Willd.), is a common invasive species throughout the American South. In southern upland mixed oak-pine forests of Mississippi, kudzu invasion generally and indiscriminately suppressed the pre-invasion plant community. Three different control methods reduced kudzu density but differed in the level of reduction achieved and in their effects on the pre-existing plant community. A combination of burning and herbicides produced the most desirable outcome in terms of restoring the pre-invasion community. Kudzu invasion significantly increased nitrate pools compared to control sites, but had no effect on ammonium or nitrite, or on the microbial processes of mineralization …

Ecological Factors Influencing Population Dynamics Of The Mississippi Sandhill Crane, Grus Canadensis Pulla, Henry W. Woolley

University of New Orleans Theses and Dissertations

My dissertation encompasses three studies involving ecological factors influencing the Mississippi sandhill crane (Grus canadensis pulla) population at Mississippi Sandhill National Wildlife Refuge. To examine influences on the historical population I studied trends in nesting, number of chicks fledged annually, and their environmental and biotic drivers during 1991-2018. I expected precipitation to be positively associated with population measures and drought, extreme heat, and predation to be inversely related to population measures. To examine the influence of current habitat food production on the crane population I quantified measures of production in 2018 and 2019 and their relationship to time …

Analysis Of Residual Neural Networks For Marine Mammal Classification Using Multi-Channel Spectrograms, Daniel T. Murphy

University of New Orleans Theses and Dissertations

Surveys of marine mammal populations are an essential part of monitoring the welfare of these animals and their ecosystems. Marine mammal vocalizations provide a reliable method of identifying most species, but passive acoustic monitoring of underwater audio may generate large quantities of data that exceed the capacity of human classifiers. Preprocessing and machine learning techniques provide a method of automating the classification process. In this study, we explore machine learning approaches to vocalization classification using convolutional neural networks with residual learning. Optimal parameters for noise-removal, spectrographic window functions, preprocessing augmentations, and multi-channel spectrogram generation are derived through a series of …

Effects Of Biological Cohesion On Wave Ripple Dynamics, Malcolm F. Cross

University of New Orleans Theses and Dissertations

In coastal environments, wave-generated oscillatory flow in the bottom boundary layer mobilizes sediment resulting in bedform generation and evolution. The presence of bedforms on the seafloor affects sediment transport, wave attenuation, and acoustic scattering. Many studies have examined the dynamics of sediment transport and the development of bedforms on the seafloor due to the interaction of waves and currents. However, these studies have relied heavily on laboratory experiments undertaken using sands with no biological influence. This research aims to understand the effects of increased cohesion within the sediment particles resulting from biological influences (e.g., extracellular polymeric substances (EPS)) on the …

Functional Material Systems For Stimuli-Responsive Interference Coloration, Milad Momtaz

Theses and Dissertations

Part I: Responsive Interference Coloration (RIC) Systems for High-Performance Humidity Sensing

High-humidity conditions (85−100% relative humidity) have a variety of effects on many aspects of our daily lives. In spite of significant progress in the development of structural coloration-based humidity sensors, enhancing the sensitivity and visual humidity resolution of these sensors at high-humidity environment remains a big challenge. In this work, high-performance colorimetric humidity sensors based on environment-friendly konjac glucomannan (KGM) are introduced. These sensors are fabricated via thin-film interference and prepared using a simple, affordable, and scalable method. An effective approach is shown for markedly improving the sensitivity and …

Solid Sorbents For Improved Chemical Separations: Applications In Nuclear Medicine And Environmental Remediation, Kevin Wolters

Theses and Dissertations

Solid sorbents have been applied to the separation of radionuclides since the advent of nuclear technology itself. First used for the cleanup and storage of radionuclides remaining from nuclear testing and nuclear power plants, these materials (e.g., inorganic and organic ion-exchange resins) were used to create solid nuclear waste forms as a way of reducing the potential for environmental contamination arising from storage of liquid wastes. The invention of nuclear medicine, which coincided with the introduction of nuclear technology, led to the need for high purity radionuclides for human use. One of the most widely used radionuclides in nuclear medicine …

Part I: A Concise Synthesis Of Microtubule Inhibitor Tryprostatin A And B And Its Analogs Part Ii: Brønsted Acid Catalyzed Reactions Of Aromatic Ketones With Ethyl Diazoacetate And Its Synthetic Scope, Khorshada Jahan

Theses and Dissertations

PART I: A CONCISE SYNTHESIS OF MICROTUBULE INHIBITOR TRYPROSTATIN A AND B AND ITS ANALOGSMicrotubules are promising targets for treating cancer by stopping the cell division in mitosis(M). Tryprostatins A and B (TPS A and B) are one of the important alkaloids for treating cancer, via microtubule inhibition. Studied found that Tryprostatins A and B act as an antimitotic agent by inhibiting cell cycle progression of tsFT210 cells in the G2/M phase at a final concentration of 50 µg/ml of TPS A and 12.5 µg/ml of TPS B, respectively. Usually, Tryprostatins A and B are isolated from natural source Aspergillus …

Singer, Legates, And Lupos' "Hot Talk, Cold Science: Global Warming's Unfinished Debate (3rd Ed.)" (Book Review), Jaclyn Lee Parrott

The Christian Librarian

No abstract provided.

Proliferation Of Chondrodonta As A Proxy Of Environmental Instability At The Onset Of Oae1a: Insights From Shallow-Water Limestones Of The Apulia Carbonate Platform, G. Del Viscio, G. Frijia, R. Posenato, P. Singh, Daniel J. Lehrmann, J. L. Payne, K. Al-Ramadan, U. Struck, K. P. Jochum, M. Morsilli

Geosciences Faculty Research

Chondrodonta is an opportunistic, oyster-like bivalve, common in shallow-water carbonates of the Cretaceous Tethyan Realm. Despite its high abundance and widespread geographic distribution, the precise relationship between the early Aptian proliferation and environmental perturbations resulting from the Oceanic Anoxic Event 1a (OAE1a), has not been investigated. Stratigraphic and geochemical analyses of the lower Aptian Chondrodonta bedsets within the inner platform limestones of the Apulia Carbonate Platform (Gargano Promontory, southern Italy) are conducted to assess the environmental controls on the Chondrodonta proliferation and its timing and causal relationship to OAE1a. Chondrodonta occurs with sparse to common individuals within requieniid rudist floatstone–rudstones, …

Characterizing Relational Values To Inform Message-Framing At The Boa Ogoi Historical Site, Cole G. Stocker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In an increasingly polarized political climate–particularly in the U.S.– environmental issues such as climate change and its effects on the environment have become hot-button partisan talking points resulting in further division. This has led to research on ways to communicate science which does not further inflame political tensions, but rather reinforces and validates the audience’s values. Science communication research provides the foundation for my case study, which focuses on characterizing the environmental values and worldviews of land managers residing and working near the Boa Ogoi Historical Site in southern Idaho. The Northwest Band of Shoshone Nation (NWBSN) is in the …

Transformation Groups And The Method Of Darboux, Brandon P. Ashley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the study of partial differential equations (PDE), one is often concerned as to whether or not explicit solutions can be obtained via various integration techniques. One such technique, known as the method of Darboux, has had particular success in solving nonlinear problems as demonstrated by the classical works of Goursat. Recently, Anderson, Fels, and Vassiliou provided a far-reaching generalization of Vessiot’s group-theoretic interpretation of the method of Darboux. This generalization allows for the characterization of Darboux integrable systems in terms of fundamental geometric invariants as well as the construction of Darboux integrable systems in general.

In this work, we …

Predictive Models Of Post-Wildfire Debris Flow Volume And Grain Size Distribution In The Intermountain West, Sara Wall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Post-fire debris flows represent the most erosive and potentially hazardous consequence associated with increasing wildfire severity. While an abundance of research has explored where they are likely to occur and their potential magnitude, investigations into understanding how they impact downstream resources are limited. Recent advancements are seeking to link predictive models together to be able to predict how erosion after wildfire may impact reservoirs and aquatic habitat downstream. However, there are two key missing pieces into our ability to examine watershed-scale impacts of post-fire erosion. These include having accurate predictions of how much sediment is likely to be deposited by …

Lithological And Geochemical Characterization Of Ramp Sediments And A Depositional Model Of The Ordovicain Garden City Formation, Northeastern Utah, Kenneth W. Kehoe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Ordovician Garden City Formation is a mostly marine limestone rock formation deposited in what is known today as the Northern Utah Basin in North America ~485.5 million years ago. Previous research on the Pogonip Group, a time equivalent rock formation located in the Ibex Basin south of the Northern Utah Basin, has identified nine cycles of sea-level fall and rise. However, these nine sea-level cycles have proven difficult to identify within the Garden City Formation due to the limited contrast between rock types within the rock formation. Previous research on the Garden City has approximated these sea-level cycles through …

Investigation And Discovery Of Novel Transition Metal Cysteamine Systems With Halogens From The First Principles Calculations, Noura Dawas Alkhaldi

Physics Dissertations

Cu-cysteamine (Cu-Cy) is a material that has the cysteamine bonded with Cu. It is a molecular photosensitizer which can be activated by visible, ultraviolet light, and X-rays to generate reactive oxygen species (ROS). Cu-Cy has been used in various applications such as solid-state lighting, radiation detection, and as treatment of both shallow and deep cancers. Hence, it is important to study the stability, electronic and optical properties of Cu-Cy as well as finding other possible cysteamine systems. The first principle theoretical investigations of novel transition metal cysteamine systems with halogens are performed by density functional theory. In the first part …

Petrophysical Studies Of Well Cuttings From A Continues Geological Profile In Hockley County, Texas, Tristan N. Tom

Earth & Environmental Sciences Theses

The Permian Basin currently leads the oil production in the United States; however, with increasing concerns for the global climate, it is crucial for oil and gas companies to operate as economically and efficiently as possible. This is where the use of well cuttings comes in, as they allow for more geological formations in the subsurface to be analyzed in depth and are cheaper to achieve than core samples. Well cuttings can be obtained from most drilling operations, and they can save on analysis time and even be analyzed on site. Before using well cuttings, it is important to ensure …

Headspace-Solid Phase Micro Extraction – Gas Chromatography – Mass Spectrometry (Hs-Spme-Gc-Ms) Analysis For Oak Barrel Flavor Compounds In Whiskey, Hailey F. Jarzynka

Chemistry & Biochemistry Theses

This study presents a method to simultaneously detect both fault compounds and oak barrel flavor compounds in whiskey using headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). A major contaminant in whiskey is geosmin and an array of oak barrel compounds includes 2-methoxy-4-methylphenol, 5-methylfurfural, guaiacol, trans-whiskey lactone, 2-methoxy-4-vinylphenol, 4-ethylguaiacol, eugenol, vanillin, and 4-ethylphenol. Geosmin is a fault compound that produces a musty or moldy taste to the whiskey and the other compounds originate from the barrels in which the whiskey is aged in and transfer to the whiskey in the aging process. Each compound was quantitated and 15 different whiskies were compared …

Electronic And Magnetic Properties Of Metal Doped Silicon-Carbide Fullerene-Type Nanostructures, Hussain Jabreel Alathlawi

Physics Dissertations

Silicon carbide (SiC) is a technologically significant material. A recent report on the abundance of C60 fullerenes in interstellar space, along with the presence of SiC precursors, sparked interest in potentially similar SiC nanostructures. C60 and C70 fullerenes were found experimentally and are an exceptionally stable form of carbon. As Si and C have similar valence electron configurations, it has been long envisioned that Si and SiC could also form similar fullerene-type structures. In this dissertation, Si30C30 fullerene-derived clusters were studied from the first principles theory, starting from an ideal Si60 fullerene template with various arrangements of silicon and carbon …

Volatiles Characterization During Whiskey Production Using Headspace - Solid Phase Microextraction - Gas Chromatography - Mass Spectrometry, Robert H. Magnuson

Chemistry & Biochemistry Theses

Whiskey is the second most consumed distilled alcoholic beverage type, by brand, on the planet behind Chinese Baijiu. A prominent component in many varieties of whiskey, maize, contributes a wide profile of compounds that undergo modification in the production pathway, ultimately influencing the final flavor profile. In this study, headspace/solid phase microextraction-gas chromatography/mass spectrometry (HS/SPME-GC/MS) was used to characterize the volatile profile of 5 different maize varieties, mashes produced from each, and 4 post-fermentation mixtures. Headspace sampling was performed using a high capacity SPME Arrow device, in an effort maximize the species detected. Compound identification was supplied by matches within …

Total Synthesis Of Imidazole-Containing Β-Carboline Alkaloids And Pyrrole-Imidazole Alkaloids, Moumita Singha Roy

Chemistry & Biochemistry Dissertations

The first part in this dissertation focuses on the development of an enantioselective total synthesis of villagorgin A, from another natural product haploscleridamine. Haploscleridamine was targeted first as it was thought that a successful approach to this family member would permit access to the other congeners through minor modifications, including conversion to villagorgin A. Moreover, villagorgin A has just one additional carbon atom compared to haploscleridamine, the introduction of which can be envisioned through a Pictet-Spengler reaction with formaldehyde. On completion of the haploscleridamine synthesis, attention was turned to the brominated congener, lissoclin C. Lissoclin C can be accessed from …

Construction Of Fluorescent Helicase Fusion Proteins For Use In Fret Studies On Helicase Function And Stoichiometry, Moneer Arabiyat

Theses and Dissertations

This thesis details the construction of N-terminal fusions of the E. coli helicase DnaB to fluorescent proteins mT-Sapphire and mVenus, and of C-terminal fusions of the hepatitis C virus NS3 helicase (NS3h) to mT-Sapphire and mVenus. These fluorescent fusion proteins were constructed to be used in FRET studies of helicase function and stoichiometry. One example is in assessing the potential oligomerization and cooperativity of NS3h protomers in unwinding RNA. Another potential use is in assessing the stoichiometry of the replisome of E. coli; older studies support a dimeric polymerase model of the replisome. Recent studies however suggest that an active …

Survivals Of Two Cooperating Species Of Animals, Joon Hyuk Kang

Faculty Publications

The purpose of this paper is to give conditions for the existence and uniqueness of positive solution to a rather general type of elliptic system of the Dirichlet problem on a bounded domain Ω" role="presentation" style="box-sizing: border-box; margin: 0px; padding: 0px; display: inline-block; line-height: normal; font-size: 16.2px; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: 0px; min-height: 0px; border: 0px; position: relative;">Ω in Rn" role="presentation" style="box-sizing: border-box; margin: 0px; padding: 0px; display: inline-block; line-height: normal; font-size: 16.2px; word-spacing: normal; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; max-height: none; min-width: …

Conceptual Insight Into The Application Of Innovative Educational Methods In Astronomy, Wahltyn A. Rattray

Theses and Dissertations

University students taking introductory astronomy courses were studied with a control group enrolled in a class with standard curriculum and an experimental group enrolled in a class with a curriculum using innovative instructional methods. Using multiple assessments, I analyzed the students’ astronomy knowledge and overall class experience to determine which curriculum was more instructionally effective. The innovative methods were developed with the ADDIE method and were based on the Karplus learning cycle which provided the framework for the astronomy curriculum. The end goal of the innovative curriculum is to produce graduates with better conceptual understanding of astronomy than with the …

Growth Kinetics Of Salmonella Spp. During Post-Harvest Storage Of Fresh And Fresh-Cut Papaya, Amandeep Singh

Theses and Dissertations

Fresh produce safety is major concern in United States. Fresh produce has been associated with numerous food-borne outbreaks each year. Salmonella has been a recurring issue in the papaya industry. Since 2010, imported papayas have been implicated in 8 multistate outbreaks associated with Salmonella spp. causing 480 illnesses, 113 hospitalization and 3 deaths. The main reason behind this problem is as fresh papaya is grown on fields where they are constantly exposed to preharvest microbial contamination through contaminated irrigation water, agricultural soil, raw manure and/or feces deposited by intruding domestic or wild animals. Moreover, majority fresh papaya is also consumed …

Dynamical Casimir Effect In A Superconducting Circuit Periodic Lattice, Andres Cuellar Vega

Theses and Dissertations

The dynamical Casimir effect (DCE) is the generation of real photons out of the quantum vacuum due to a rapid modulation of boundary conditions for the electromagnetic field, such as a mirror oscillating at speeds comparable to the speed of light. Previous work demonstrated experimentally that DCE radiation can be generated in electrical circuits based on superconducting microfabricated waveguides, where a rapid modulation of boundary conditions corresponding to semi-transparent mirrors is realized by tuning the applied magnetic flux through superconducting quantum-interference devices (SQUIDs) that are embedded in the waveguide circuits. We propose a novel SQUID periodic lattice architecture, in which …

Microwave Assisted Depolymerization Of Waste Pet Bottles Via Glycolysis, Kingsley Bassey

Theses and Dissertations

One of the most promising and sustainable chemical depolymerization methods for managing the complex environmental problem arising from waste poly(ethylene) terephthalate (PET) bottles is glycolysis. However key challenges such as longer reaction times, complex separation procedures for the depolymerized products, selectivity, thermally stable catalyst need to be addressed.

In this work, we investigated the glycolysis of waste PET under microwave conditions using 1,5,7-Triazabicyclo [4.4.0] dec5-ene (TBD) and 1,8-Diazabicyclo [5.4.0] undec-7-ene (DBU) as catalyst. We evaluated the effect of reaction parameters such as temperature, catalyst concentration and time on PET depolymerization rate (%PET conversion) and product yield. The reaction was conducted …

Comparison Of Statistical Methods For Modeling Count Data With An Application To Length Of Hospital Stay, Gustavo A. Fernandez

Theses and Dissertations

Hospital length of stay (LOS) is a key indicator of hospital care management efficiency, cost of care, and hospital planning. Therefore, understanding hospital LOS variability is always an important healthcare focus. Hospital LOS data are count data, with discrete and nonnegative values, typically right-skewed, and often exhibiting excessive zeros. Numerous studies have been conducted to model hospital LOS to identify significant predictors contributing to its variability. Many researchers have used linear regression with or without logarithmic transformation of the outcome variable LOS, or logistic regression on a dichotomized LOS. These regression methods usually violate models’ assumptions and are subject …

Electrospun Polyetherimide And Polybenzimidazole Fibers And Composites, Fatema Ha-Mim Binta Hafiz

Theses and Dissertations

In this study, polymer micro- and nanocomposite fibers with PBI and PEI as polymer, and exfoliated graphite and nitroxide-functionalized graphene oxides have been prepared. Electrospinning has been chosen as a fiber processing technique. This work describes the electrospinning process of the mentioned polymer fibers and composite fibers followed by their characterization by XRD, ATR, SEM, TGA, DSC and Tensile testing.

Assessment And Monitoring Of Deltaic Wetlands And Fluvial Systems: Refining And Validating A Multimetric Index Of Resaca Ecosystem Health, David Lecusay Jr.

Theses and Dissertations

Resacas are ancient distributary channels of the lower Rio Grande River historically serving as floodwater drainage pathways onto the Laguna Madre, Texas. Resacas provide numerous ecosystem services and critical habitat for many species. Mainly influenced by urbanization, integrating a multimetric index for assessing and monitoring resaca ecosystem health is required for adaptive management. The Resaca Health Index (RHI) integrates structural and functional components: (1) nonredundant metrics describing fish communities (Fish Community Index); (2) Trophic State Index derived from Secchi depth; (3) decay constant from riparian vegetation leaf litter decomposing in the water column; and (4) a riparian quality index based …

Factors Influencing Intent To Take A Covid-19 Test In The United States, Sheila Rutto

Theses and Dissertations

In 2020, COVID-19 became the first pandemic in the world’s history that brought the entire world to an abrupt and unexpected halt. Since the first reported case of the disease to date, the novel coronavirus has been able to wreak havoc in literary every corner of the globe and left an ever-growing number of unprecedented fatalities. The normal way of life has been disrupted, and the level of uncertainty about the end of this pandemic continues to manifest to many. Due to the urgency to bring this pandemic under control, medical officers have been able to recommend actions that people …

Effects Of Collaborative Group Activities On Students’ Interest, Course Participation, And Performance In An Online Physics Course, Airik R. Sanchez

Theses and Dissertations

The purpose of this study was to investigate the impact of the use of collaborative work activities in online physics courses as perceived by students. Nearly identical surveys were administered at the beginning and end of two semesters to ascertain student perception on the impact of the utilization on their level of interest, participation, performance as well as teamwork skills. The results show that the majority of the population tested strongly agree that collaborative work had significant effect on all core areas tested, and they support the notion that it should be further utilized in both lecture and lab portions …