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2021

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Kudzu Invasion And Control In Southern Upland Forests Of Mississippi, Gina M. Profetto Dec 2021

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

LSU 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 Dec 2021

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

LSU 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 …


Silver Microparticle And Submicron Wire - Polylactic Acid Composites For Additive Manufacturing, Jenna W. Robichaux Dec 2021

Silver Microparticle And Submicron Wire - Polylactic Acid Composites For Additive Manufacturing, Jenna W. Robichaux

LSU New Orleans Theses and Dissertations

This thesis explores the incorporation of silver microparticle and submicron wire additives into thermoplastic filament feedstock for fused filament fabrication (FFF) to create multifunctional three-dimensional (3D) printable composites. The impact of silver microparticle and submicron wire additives on mechanical behavior along with antibacterial effect of the silver microparticle and submicron wire additives on printed objects were assessed.

Composite FFF filaments were fabricated by solution processing, granulation, and extrusion. Differential Scanning Calorimetry (DSC) was conducted to measure the glass transition and melting point temperatures of the composite filaments for 3D printing. The effect of the additive addition on the thermal properties …


Parents Of Children With Hearing Loss: Meeting Parents’ Needs And Concerns Through The Early Intervention Process, Sara Chaddock Dec 2021

Parents Of Children With Hearing Loss: Meeting Parents’ Needs And Concerns Through The Early Intervention Process, Sara Chaddock

LSU New Orleans Theses and Dissertations

The purpose of this study is to develop a deeper understanding of needs of parents of children with hearing loss during the crucial early years of a child’s life, to understand how those needs are met through birth-to-three Early Intervention programs, and to determine if parent identified needs align with the recommended practices for Early Intervention for children with hearing loss stated by the Division for Early Childhood (DEC) and the Joint Committee of Infant Hearing (JCIH). This study used a quasi-structured web-based survey with both closed and open-ended questions. Three themes emerged from this study: needs for supports for …


Analysis Of Residual Neural Networks For Marine Mammal Classification Using Multi-Channel Spectrograms, Daniel T. Murphy Dec 2021

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

LSU 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 Dec 2021

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

LSU 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 …


Fast & Efficient Simulation For Long Polymeric Chains, Naeyma N. Islam Dec 2021

Fast & Efficient Simulation For Long Polymeric Chains, Naeyma N. Islam

LSU New Orleans Theses and Dissertations

No abstract provided.


Cutinase From Amycolatopsis Mediterannei: Marked Activation And Stabilisation In Deep Eutectic Solvents, Yeqi Tan, Gemma K. Kinsella, Gary T. Henehan, Barry J. Ryan Dec 2021

Cutinase From Amycolatopsis Mediterannei: Marked Activation And Stabilisation In Deep Eutectic Solvents, Yeqi Tan, Gemma K. Kinsella, Gary T. Henehan, Barry J. Ryan

Articles

Amycolatopsis mediterranei cutinase (AmCut) has potential biocatalytic applications in plastics degradation and ester synthesis. Deep Eutectic Solvents (DES) are next generation biodegradable solvents for biocatalysis. However, the behaviour of cutinase enzymes in DES is little studied. Herein, we examine the effect of selected DES, and their components, on AmCut activity and stability. Low amounts (10% v/v) of DES (choline chloride:glycerol; 1:1 mole ratio) caused striking activation of AmCut (over 2-fold). Further examination showed that the choline chloride component of DES caused the observed activation. This is the first report of activation of a cutinase by a small molecule. At higher …


A Comparative Study Of Machine Learning-Based Approach For Network Traffic Classification, Kien Trang, An Hoang Nguyen Dec 2021

A Comparative Study Of Machine Learning-Based Approach For Network Traffic Classification, Kien Trang, An Hoang Nguyen

Knowledge Engineering and Data Science

Internet usage has increased rapidly and become an essential part of human life, corresponding to the rapid development of network infrastructure in recent years. Thus, protecting users’ confidential information when joining the global network becomes one of the most significant considerations. Even though multiple encryption algorithms and techniques have been applied in different parties, including internet providers, and web hosting, this situation also allows the hacker to attack the network system anonymously. Therefore, the significance of classifying network data streams to improve network system quality and security is attracting increasing study interests. This work introduces a machine learning-based approach to …


Cnn Based Face Recognition System For Patients With Down And William Syndrome, Endang Setyati, Suharyono Az, Subroto Prasetya Hudiono, Fachrul Kurniawan Dec 2021

Cnn Based Face Recognition System For Patients With Down And William Syndrome, Endang Setyati, Suharyono Az, Subroto Prasetya Hudiono, Fachrul Kurniawan

Knowledge Engineering and Data Science

Down syndrome, also known as trisomy genetic condition, is a genetic disorder that affects many people. Williams syndrome is a hereditary disorder that can affect anyone at birth. It marks medical and cognitive issues, such as cardiovascular illness, developmental delays, and learning impairments. This is accompanied by exceptional verbal abilities, a gregarious attitude, and a passion for music. Down syndrome and William Syndrome are both genetic illnesses. However, it can be distinguished from the arrangement of chromosome 21. Down syndrome and William syndrome can also be identified by recognizing faces, or facial characteristics, such as observing particular facial features. Therefore, …


A Method For Visualizing Water Flow Through Modified Root Zones, Dallas M. Williams Dec 2021

A Method For Visualizing Water Flow Through Modified Root Zones, Dallas M. Williams

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

As the number of impervious surfaces in urban environments increases, the ability of modified root zones to infiltrate water is becoming more important. Current methods of tracing water flow through soil profiles include excavating large pits in situ or analyzing soil cores in the laboratory with computed tomography or magnetic resonance imaging. While useful, these methods may not be suitable for urban settings or practical in every laboratory. We propose a new method that is less invasive, does not require extensive technical equipment and can reliably trace water movement through the soil profile in order to calculate flow rate based …


Determining The Presence Of Biological Fluids In Peruvian Mummy Cloths Using The Liquid Chromatography Quadruple Time Of Flight Instrument, Tim Perksen, Joshua Sebree Ph.D. Dec 2021

Determining The Presence Of Biological Fluids In Peruvian Mummy Cloths Using The Liquid Chromatography Quadruple Time Of Flight Instrument, Tim Perksen, Joshua Sebree Ph.D.

Fall 2021 - Chemical Analysis Class Projects

A poster presenting the processes used and the results of analyzing the cloth from Peruvian mummies for the presence of biological fluids.


The Role Of The Serine/Threonine Phosphatase Pstp In The Mycobacterial Cell Wall Regulation, Farah Shamma Dec 2021

The Role Of The Serine/Threonine Phosphatase Pstp In The Mycobacterial Cell Wall Regulation, Farah Shamma

Biology Dissertations - Archive

Mycobacterium tuberculosis (Mtb) is the causative agent of the deadly infection Tuberculosis (TB). The current standard antibiotic regimen for TB treatment combines fours drugs to be taken for at least six months. Mtb shows intrinsic phenotypic tolerance to antibiotics contributing to the long treatment regimen. In addition, Mtb cells can achieve a non-replicating state exhibiting antibiotic tolerance, reduced metabolism and altered cell wall staining. The changes in the cell wall and reduced permeability to antibiotics in stressed cells suggest that the regulation of the cell wall is a major contributor to antibiotic tolerance. The mycobacterial cell wall consists of covalently …


Adapting Animals: Nineteenth-Century British Literature, Science, And Media, Kristen Layne Figgins Dec 2021

Adapting Animals: Nineteenth-Century British Literature, Science, And Media, Kristen Layne Figgins

Graduate Theses and Dissertations

In the nineteenth century, Charles Darwin and other proponents of evolutionary theory provided a theoretical framework for discussing the question of humanity’s place in the world. These nascent theories emphasized the shared animal nature of humans and the nonhuman creatures who had once occupied a distinctly lower place on the chain of being. My dissertation addresses the question of how nineteenth-century scientific attitudes about animals were reflected in the literature of the period. By examining culture-texts from the nineteenth century, it is clear that literature was an active participant in extending scientific knowledge, often by playing with the blending categorical …


The Role Of Sex: An Analysis Of U.S. Attitudes Toward Climate Change, Chloe Riggs Dec 2021

The Role Of Sex: An Analysis Of U.S. Attitudes Toward Climate Change, Chloe Riggs

Graduate Theses and Dissertations

This study analyzes the intersection of sex, environmental risk perception of climate change, and feminism. More specifically, with a sample size of 8,280 respondents from the American National Election Studies (ANES) 2020 Times Series Study, this research examines the relationship between pro-environmental attitudes and sympathy for feminism, controlling for sex, as well as if a measure of sympathy for feminism influences pro-environmental attitudes, controlling for demographic (age, education, race, sex, and income) and political preference (political ideology and party affiliation) variables. Previous literature strongly supports a sex gap in risk perception, a pattern known as the White Male Effect (WME) …


Greenhouse Tomatoes: Process Simulation, Juan Gabriel Marin Jr. Dec 2021

Greenhouse Tomatoes: Process Simulation, Juan Gabriel Marin Jr.

Graduate Theses and Dissertations

Growing population demand and challenges brought on by climate change have spurred the need for more resilient fruit and vegetable supply chains. One agricultural technology of significant interest is the use of greenhouses for food production. Greenhouses create a stable and adaptable environment for crops such as tomatoes to grow year-round. Fresh tomatoes are the second most consumed vegetable per capita in U.S. diets, currently averaging 20.7 pounds. The growing consumption of fresh tomatoes has been the result of increasing cultural diversity in the United States.

To meet the growing demand, Venlo-type greenhouses have been frequently used by growers. It …


Data Analytics For Sustainable Food And Agriculture Systems, Megan Lord Reavis Dec 2021

Data Analytics For Sustainable Food And Agriculture Systems, Megan Lord Reavis

Graduate Theses and Dissertations

The increasing concentration of anthropogenic greenhouse gases in the atmosphere is altering the climate, posing a serious threat to global agriculture and food security. Agriculture and food production contribute a quarter of all GHG emissions produced, so there is a critical need to limit emissions in this area while increasing food production to feed the anticipated 10 billion people by 2050. To address the needs of the future, data-driven solutions are needed to guide decision-making and provide support for actionable climate mitigation and survival strategies. Research efforts must be focused on analyzing problems on multiple scales, identifying new ways to …


Investigation Of Optical And Structural Properties Of Gesn Heterostructures, Oluwatobi Gabriel Olorunsola Dec 2021

Investigation Of Optical And Structural Properties Of Gesn Heterostructures, Oluwatobi Gabriel Olorunsola

Graduate Theses and Dissertations

Silicon (Si)-based optoelectronics have gained traction due to its primed versatility at developing light-based technologies. Si, however, features indirect bandgap characteristics and suffers relegated optical properties compared to its III-V counterparts. III-Vs have also been hybridized to Si platforms but the resulting technologies are expensive and incompatible with standard complementary-metal-oxide-semiconductor processes. Germanium (Ge), on the other hand, have been engineered to behave like direct bandgap material through tensile strain interventions but are well short of attaining extensive wavelength coverage. To create a competitive material that evades these challenges, transitional amounts of Sn can be incorporated into Ge matrix to form …


Engineering Fluorescently Labeled Human Fibroblast Growth Factor One Mutants And Characterizing Their Photophysics Properties Towards Designing Fret Assays, Mamello Mohale Dec 2021

Engineering Fluorescently Labeled Human Fibroblast Growth Factor One Mutants And Characterizing Their Photophysics Properties Towards Designing Fret Assays, Mamello Mohale

Graduate Theses and Dissertations

Human fibroblast growth factor one (hFGF1) belongs to a family of 22 FGF members produced by fibroblast cells. Cell signaling during physiological processes of angiogenesis and wound healing occurs when hFGF1 binds to its receptor (FGFR). However, when heterogenous homeostasis is not maintained, fibroblast cells exhibit excessive proliferation which can lead to a myriad of cancers. smFRET is an ultrasensitive distant dependent (1-10 nm) technique capable of resolving such heterogeneity in structural dynamics and binding affinities (Kd). Therefore, we successfully designed and characterized fluorescently labeled hFGF1 tracers which span the visible light region of the electromagnetic spectrum for use in …


Cover Crop Effects On Infiltration, Aggregate Stability, And Water Retention On Loessial And Alluvial Soils Of The Lower Mississippi River Valley, Shelby G. Lebeau Dec 2021

Cover Crop Effects On Infiltration, Aggregate Stability, And Water Retention On Loessial And Alluvial Soils Of The Lower Mississippi River Valley, Shelby G. Lebeau

Graduate Theses and Dissertations

Cover crops are a widely considered practice to improve soil health in the form of erosion control, organic matter additions, and improving water-holding capacity. Despite the well-documented benefits, little is known about the effect of cover crops on soils in the Lower Mississippi River Valley (LMRV), an area historically dominated by intensive cultivated agriculture, with soils prone to erosion, and unsustainable aquifer withdrawals for irrigation. The main objective of this study was to evaluate the effects of cover crops [with cover crops (CC) and without cover crops (NCC)] on near-surface soil physical/chemical- and infiltration-related properties, aggregate stability, and water retention. …


Does Whispering Improve Children’S Memory? Comparing Auditory Vigilance And Salience Hypotheses, Christina M. Barnes Dec 2021

Does Whispering Improve Children’S Memory? Comparing Auditory Vigilance And Salience Hypotheses, Christina M. Barnes

Graduate Theses and Dissertations

Oral communication is one of the primary tools children use to learn new information and speech registers can deliver additional meaning to the words someone uses. Cirillo’s (2004) vigilance hypothesis states “Whispering can affect the psychobiological state of recipients, and in particular raise their auditory vigilance” (Cirillo, 2004, p. 76). Building on this theory, the current study investigates the role of whispering and children’s memory by examining a whispering vigilance, whispering salience which focused on the changes between normal and whisper registers, and combined vigilance and salience hypotheses to determine if whispering contributes to the recall of information. Using video …


Evaluation Of Nitrous Oxide Emissions From Furrow-Irrigated Rice On A Silt-Loam Soil In Arkansas, Jordan M. Slayden Dec 2021

Evaluation Of Nitrous Oxide Emissions From Furrow-Irrigated Rice On A Silt-Loam Soil In Arkansas, Jordan M. Slayden

Graduate Theses and Dissertations

As the number one rice (Oryza sativa)-producing state in the United States, Arkansas also ranks fourth as the largest user of groundwater. Recently, due to the development of drought- resistant hybrid cultivars, the furrow-irrigated rice production system has become an increasingly popular alternative to traditional flood-irrigated production with respect to conserving groundwater and maintaining yield. However, other environmental parameters, like greenhouse gas emissions, specifically nitrous oxide (N2O), have yet to be evaluated under furrow-irrigated rice. The objectives of this study were to i) evaluate the effects of site position (i.e., up-, mid-, and down-slope) and tillage treatment [i.e., conventional tillage …


Optimization Of Nitrogen Removal Rate In One-Stage Reactor Through Partial Nitrification Anammox Process During Direct Treatment Of Poultry Litter Wastewater, Yiting Xiao Dec 2021

Optimization Of Nitrogen Removal Rate In One-Stage Reactor Through Partial Nitrification Anammox Process During Direct Treatment Of Poultry Litter Wastewater, Yiting Xiao

Graduate Theses and Dissertations

Anammox is an increasingly common process used for the treatment of reject water and even mainstream wastewater due to its low oxygen demand. However, anammox is not commonly utilized in the direct treatment of poultry litter because of the high organic content, which would inhibit the anammox process. Thus, this project is aimed at optimizing the nitrogen removal rate through partial nitrification anammox process (PN/A) to treat synthetic poultry litter wastewater. Nitrogen removal efficiencies will therefore be improved through optimizing the combination of three operating parameters including hydraulic retention time (HRT), dissolved oxygen (DO) concentration, and carbon to nitrogen (C/N) …


Enzymatic Degradation Of Microcystin-Lr By Microcystinase (Mlra), Faisal Alqhtani Dec 2021

Enzymatic Degradation Of Microcystin-Lr By Microcystinase (Mlra), Faisal Alqhtani

Graduate Theses and Dissertations

Microcystin-LR (MC-LR) is affecting the water supply worldwide. Hence, a way to eliminate this toxin is an essential target. In this study, successful cloning of the mlrA gene and producing MlrA enzyme that can degrade the cyclic MC-LR to linearized MC-LR was done. MlrA protein was expressed in Escherichia coli BL-21 (E. coli). Also, enhancing the MlrA yield by adding nickel to LB media was a success in producing more MlrA enzyme from the same volume. Even though the enzyme showed no activity after adding Ni, the enzyme was expressed at a higher yield. Furthermore, it was to investigate adding …


Open Education Resources And The Academic Library, Jeanette A. Parker Dec 2021

Open Education Resources And The Academic Library, Jeanette A. Parker

The Christian Librarian

Librarians have an opportunity to assist faculty and students in adoption and use of OER, or Open Educational Resources. Faculty and students present differing perspectives and responses to OER that may inhibit their use. Libraries are known for providing access to resources and educational training or workshops on the use of new technologies and existing or new resources. Libraries are also accustomed to providing proxied access to online resources, hosting repositories and developing policies for management, curation and collection of a wide array of materials and resources. By helping to develop and organize an OER initiative of any kind at …


A Multigrid Homotopy Method For Computing Eigenfunctions Of Differential Operators With Two-Dimensional Heterogeneity, Chelsea Drum Dec 2021

A Multigrid Homotopy Method For Computing Eigenfunctions Of Differential Operators With Two-Dimensional Heterogeneity, Chelsea Drum

Master's Theses

In this thesis, we develop an accurate algorithm for computing the smallest eigenvalues of the self-adjoint spatial differential operator for the two-dimensional heat equation with a piecewise constant coefficient and periodic boundary conditions. The piecewise constant coefficient is created by the discontinuity of the diffusivity coefficient across the interfaces between two or more heterogeneous materials. Our method involves the combination of the well-known Inverse Iteration with a multigrid homotopy.


Wear Behaviors Of Process Cheese With Varying Formulations And The Development Of Predictive Models On Shreddability, Jason Young Dec 2021

Wear Behaviors Of Process Cheese With Varying Formulations And The Development Of Predictive Models On Shreddability, Jason Young

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Process Cheese is manufactured by grinding, mixing, and heating with agitation one or more of the same varieties of natural cheese with an emulsifying agent to create a cheese with desirable properties. After process cheese is made, it is often sliced or shredded. Some of its properties affect how well it can be sliced or shredded and can lead to loss of material due to cheese sticking to equipment or being too crumbly. The loss of material, called wear behavior can incur significant losses to cheese manufacturing operations. The purpose of this study was to produce process cheese formulations with …


Examining The Relationship Between Lep Status And Delinquency Amongst High Schools Across America, Adrian Jesus Campos Dec 2021

Examining The Relationship Between Lep Status And Delinquency Amongst High Schools Across America, Adrian Jesus Campos

Dissertations (2016-Present)

This research is intended to examine the relationship between the enrollment of Limited English Proficient (LEP) students in American high schools and the rate of delinquency on campus. While the stigma and general belief that immigrants and criminality are correlated has existed throughout American History, empirical research findings have generally indicated the inverse to be true and often find that immigrants engage in lower rates of delinquency in comparison to their non-immigrant counterparts. Previous work in the field has primarily identified immigrants by legal or technical categorization, primarily nativity and immigrant status. Fewer are the studies who identify this group …


Techniques For The Enantioselective Asymmetric Synthesis Of Benzyl Substituted Malonic Acid Esters, Madison Hansen Dec 2021

Techniques For The Enantioselective Asymmetric Synthesis Of Benzyl Substituted Malonic Acid Esters, Madison Hansen

Honors Theses

A popular method for the enantioselective synthesis of substituted malonic half esters is hydrolysis via Pig Liver Esterase (PLE), however some substrates produce low enantiomeric excess, namely benzyl-substituted malonic esters. Presented here are alternative methods explored for this synthesis, the first being phase-transfer catalyzed hydrolysis via N-benzyl quaternary ammonium salts derived from cinchona alkaloids. The second method utilized chiral auxiliary directed benzylation with auxiliaries including menthol and oxazolidinones. Though unsuccessful, this research provided valuable groundwork in the investigation for the enantioselective asymmetric synthesis of benzyl-substituted malonic acid esters.

Keywords: Pig Liver Esterase, Enantioselectivity, Phase-Transfer Catalysis, Cinchona Alkaloids, Quaternary Ammonium …


Factors Associated With Gestational Diabetes Among Women Registered At Secondary Hospitals In Karachi, Pakistan, Sumaira Feroz Ali, Tazeen S. Ali, Arusa Lakhani, Zaib Nadeem Dec 2021

Factors Associated With Gestational Diabetes Among Women Registered At Secondary Hospitals In Karachi, Pakistan, Sumaira Feroz Ali, Tazeen S. Ali, Arusa Lakhani, Zaib Nadeem

Journal of Asian Midwives (JAM)

Introduction: Few things are proven, there are modifiable and non-modifiable factors that could impact on the health of pregnant women who have Gestational Diabetes Millitus (GDM). However, case control studies are lacking that explore the modifiable factors and identify which modifiable factors are associated with GDM.
Purpose: The aim of this study was to identify the modifiable associated risk factors of GDM among women at 32 to 40 weeks of gestation.
Methodology: A case-control study design was conducted at secondary hospitals for women and children in Karachi, Pakistan. The data were collected from 100 cases and same number of controls, …