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Effects Of Riverine Barriers On Avian Evolution In The Amazon Basin, Andre Eugene Moncrieff Dec 2022

Effects Of Riverine Barriers On Avian Evolution In The Amazon Basin, Andre Eugene Moncrieff

LSU Doctoral Dissertations

The high biodiversity found in the Amazon Basin has long captivated the attention of naturalists and evolutionary biologists seeking to explain its origins. Early observations by Alfred Wallace highlighted the role of rivers in delimiting the geographic ranges of many species; furthermore, where rivers narrow towards their headwaters, he noted that some species cross rivers freely. A major goal of this dissertation is to investigate how these and other observations about riverine barriers might inform our understanding of how speciation unfolds in Amazonia. My approach involved generating genomic data with dense geographic sampling for manakins in the genus Lepidothrix, …


Light-Weight Structural Optimization Through Biomimicry, Machine Learning, And Inverse Design, Adithya Challapalli Dec 2022

Light-Weight Structural Optimization Through Biomimicry, Machine Learning, And Inverse Design, Adithya Challapalli

LSU Doctoral Dissertations

In load-bearing lightweight architectures, cellular materials were frequently utilized. While octahedron, tetrahedron, and octet truss lattice truss were built for lightweight architectures with stretching and flexural dominance, it can be believed that new cells could easily be designed that might perform much better than the present ones in terms of mechanical and architectural characteristics. Machine learning-based structure scouting and design improvisation for better mechanical performance is a growing field of study. Additionally, biomimicry—the science of imitating nature’s elements—offers people a wealth of resources from which to draw motivation as they work to create a better quality of life.

Here, utilizing …


Application Of Distributed Fiber-Optic Sensing For Pressure Predictions And Multiphase Flow Characterization, Gerald Kelechi Ekechukwu Dec 2022

Application Of Distributed Fiber-Optic Sensing For Pressure Predictions And Multiphase Flow Characterization, Gerald Kelechi Ekechukwu

LSU Doctoral Dissertations

In the oil and gas industry, distributed fiber optics sensing (DFOS) has the potential to revolutionize well and reservoir surveillance applications. Using fiber optic sensors is becoming increasingly common because of its chemically passive and non-magnetic interference properties, the possibility of flexible installations that could be behind the casing, on the tubing, or run on wireline, as well as the potential for densely distributed measurements along the entire length of the fiber. The main objectives of my research are to develop and demonstrate novel signal processing and machine learning computational techniques and workflows on DFOS data for a variety of …


Pnp Maxtools: Autonomous Parameter Control In Maxmsp Utilizing Mir Algorithms, Austin Alexander Franklin Dec 2022

Pnp Maxtools: Autonomous Parameter Control In Maxmsp Utilizing Mir Algorithms, Austin Alexander Franklin

LSU Doctoral Dissertations

This research presents a new approach to computer automation through the implementation of novel real-time music information retrieval algorithms developed for this project. It documents the development of the PnP.Maxtools package, a set of open source objects designed within the popular programming environment MaxMSP. The package is a set of pre/post processing filters, objective and subjective timbral descriptors, audio effects, and other objects that are designed to be used together to compose music or improvise without the use of external controllers or hardware. The PnP.Maxtools package objects are designed to be used quickly and easily using a `plug and play' …


Development Of Functional Markers For Resistance To Smut And Identification Of Genes Differentially Expressed In Response To Brown Rust In Sugarcane, Jose David Cortes Dec 2022

Development Of Functional Markers For Resistance To Smut And Identification Of Genes Differentially Expressed In Response To Brown Rust In Sugarcane, Jose David Cortes

LSU Doctoral Dissertations

Smut, caused by Sporisorium scitamineum and brown rust, caused by Puccinia melanocephala, are two of the most important diseases that affect sugarcane production in Louisiana and worldwide. Smut continues to cause losses in the breeding program in Louisiana. Therefore, a QTL analysis was conducted to identify molecular markers associated with resistance in F1 progeny (162) of a biparental cross between susceptible cultivar L 99-233 and resistant HoCP 96-540. Using 1,574 single-dose SNP markers, a total of 253 linkage groups (LG) were obtained with a genome coverage of 24,580.15 cM. Six QTLs were localized on five LGs. The highest …


Estimation Of Economic Risk From Coastal Natural Hazards In Louisiana, Rubayet Bin Mostafiz Nov 2022

Estimation Of Economic Risk From Coastal Natural Hazards In Louisiana, Rubayet Bin Mostafiz

LSU Doctoral Dissertations

Louisiana, U.S.A., is among the most vulnerable areas globally to coastal natural hazards, with risk vulnerability likely increasing. The risks associated with non-tropical-cyclone hazards in Louisiana’s coastal zone have been understudied. This research enhances present and future (i.e., 2050) Louisiana risk assessment using locally-weighted, model-based hazard frequency/intensity and population projections.

Results suggest that property risks associated with extreme cold temperature and tornado are and will remain costlier than those for hail and lightning. Property risks of extreme cold temperature and hail are projected to decrease with the expected warming temperatures, with those of all four of these hazards peaking in …


The Effects Of Tillage And Cover Crops On Crop Yield And Soil Properties In Wheat Double-Cropping Systems, Peters E. Egbedi Nov 2022

The Effects Of Tillage And Cover Crops On Crop Yield And Soil Properties In Wheat Double-Cropping Systems, Peters E. Egbedi

LSU Doctoral Dissertations

This three-year study was conducted on a commerce silt loam soil at the Northeast Research and Experiment Station near St. Joseph, Louisiana to evaluate the following objectives: 1) evaluate crop yield response to tillage, winter, and summer cover crops in wheat double-cropping systems. 2) evaluate the effects of tillage, winter and summer cover crops on soil properties under different cropping systems. 3) quantify the economic benefits of double-cropping, cover cropping and monoculture systems under conventional and no tillage practices. A winter cover crop (WCC) mix (winter wheat (Triticum aestivum and Austrian winter pea (Pisum sativum) and summer …


Studies Of Roseau Cane Dieback In The Lower Mississippi River Delta Based On Remote Sensing Data Including Landsat, Worldview, And Drone, Nan Shang Nov 2022

Studies Of Roseau Cane Dieback In The Lower Mississippi River Delta Based On Remote Sensing Data Including Landsat, Worldview, And Drone, Nan Shang

LSU Doctoral Dissertations

This research focused on the Roseau cane (Phragmites australis) dieback assessment in the lower MRD of Louisiana and introduced a comprehensive and systematic multi-source remote sensing method for assessing wetland and Roseau cane dieback and habitat dynamics analysis from three scale levels from large-scale to small scale.

Large-scale historical vegetation/land change analyses were conducted in the lower MRD based on Landsat in the past two decades (2001 - 2021). A strong increasing trend of vegetation was found since 2005. Around 51 km2 ofdieback area was detected which accounts for 11% of the overall vegetation coverage. This research …


Numerical Investigation Of Heat Generation And Accumulation Contributing To Elevated Temperature In Msw Landfills, Alborz Fathinezhad Nov 2022

Numerical Investigation Of Heat Generation And Accumulation Contributing To Elevated Temperature In Msw Landfills, Alborz Fathinezhad

LSU Doctoral Dissertations

Landfills are complex geostructures which contains organic and inorganic municipal, and in some cases industrial, wastes and are expected to remain operational for long times. Due to the complex nature of physical, chemical, biological, and thermal reactions that carry on within the depths of a landfill, unexpected incidents such as elevated temperatures could become inevitable. While uncommon to happen, elevated temperatures cause health and environmental issues such as odors, rapid settlements, slope instabilities. In addition, elevated temperatures can negatively impact engineered components in composite bottom liners, cover systems, leachate collection, and gas extraction and recovery systems.

Air intrusion into municipal …


Spatiotemporal Transcriptome Diversity And Responses To Salinity Tolerance In The Extremophyte Schrenkiella Parvula, Chathura Wijesinghege Nov 2022

Spatiotemporal Transcriptome Diversity And Responses To Salinity Tolerance In The Extremophyte Schrenkiella Parvula, Chathura Wijesinghege

LSU Doctoral Dissertations

Schrenkiella parvula is an extremophyte model related to the most widely studied plant model, Arabidopsis thaliana and Brassica crops in the mustard family (Brassicaceae). It can thrive in highly saline environments where the soil is enriched in Na+, K+, Li+, borates, and chlorides. Understanding how this extremophyte can survive high salinity with genomic adaptations can provide insight into developing stress resilient crops in the future. Gene expression of S. parvula in response to salt has been investigated using shoot and root tissue from mature vegetative-phase plants. However, prior studies have not examined the transcript …


The Applied Use Of Zein Nanoparticles In Agriculture, Colin Bonser Nov 2022

The Applied Use Of Zein Nanoparticles In Agriculture, Colin Bonser

LSU Doctoral Dissertations

Nanotechnology is a multifaceted and a promising strategy in agricultural pest management for the development of insecticides or insecticide carriers. Research has shown that nanoparticles increase stability and efficacy of entrapped chemical pesticides to prevent active ingredient degradation while improving chemical stability and solubility. The following work evaluated nanoparticles synthesized from biopolymers, materials that originate from renewable sources also have an increased biodegradability.
Work was conducted under laboratory, greenhouse, and field conditions to test the biopoloymers as possible insecticide and insecticide carriers. The primary biopolymer evaluated in the following studies was zein, although lignin and chitosan were also evaluated. Overall, …


Experimental Music And Collaboration: Developing Artistry Through Performance Practice, John Lambert Nov 2022

Experimental Music And Collaboration: Developing Artistry Through Performance Practice, John Lambert

LSU Doctoral Dissertations

This project locates collaboration and collaborative performance as a potential site for artistic growth. This study analyzes six collaborative projects: composed pieces for electric guitar accompanying a staged performance of collaged texts, an audio-visual installation, the preparation of several short pieces to accompany choreographed dances, a 90-minute soundtrack to a performance mixed live, an ongoing improvisational duo, and a live visuals performance to accompany Sunburned Hand of the Man at Duke University. It traces the growth of my artistry while also providing a method for both doing and writing about collaboration. In addition, it offers a model for understanding collaborative …


Esterase Mediated Insecticide Resistance In The Southern House Mosquito, Culex Quinquefasciatus, Vivek Pokhrel Nov 2022

Esterase Mediated Insecticide Resistance In The Southern House Mosquito, Culex Quinquefasciatus, Vivek Pokhrel

LSU Doctoral Dissertations

Much is known about the development of insecticide resistance associated with targeted application against insect populations. However, off-target selection by applications of insecticides in agricultural and residential sites also impacts development of insecticide resistance and is understudied. Similarly, the impact of selecting one life stage of mosquitoes on the insecticide susceptibility of different life stages is largely unknown. The first part of this study shows that susceptibility to chlorantraniliprole, which is applied in rice and sugarcane fields in LA, decreased (5.7 to12-fold) in populations of Culex quinquefasciatus collected from near these fields compared to a reference field strain. In addition, …


Sers Platform For Single Fiber Endoscopic Probes, Debsmita Biswas Nov 2022

Sers Platform For Single Fiber Endoscopic Probes, Debsmita Biswas

LSU Doctoral Dissertations

Molecular detection techniques have huge potential in clinical environments. In addition to many other molecular detection techniques, endoscopic Raman spectroscopy has great ability in terms of minimal invasiveness and real-time spectra acquisition. However, Raman Effect is low in sensitivity, limiting the application. Surface-Enhanced Raman Scattering (SERS), addresses this limitation. SERS brings rough nano-metallic surfaces in contact with specimen molecules which enormously enhances Raman signals. This provides Raman spectroscopy with immense capabilities for diverse fields of applications.

Generally, in clinical probe applications, the spectrometer is brought near the target molecules for detection. Typically, optical fibers are used to couple spectrometers to …


Fish And Invertebrate Community And Trophic Structure In The Gulf Of Mexico Coastal Plains Watersheds Across Varying Hydrologic Connectivity., Erin Elizabeth Thayer Nov 2022

Fish And Invertebrate Community And Trophic Structure In The Gulf Of Mexico Coastal Plains Watersheds Across Varying Hydrologic Connectivity., Erin Elizabeth Thayer

LSU Doctoral Dissertations

Subtropical Northern Gulf of Mexico coastal plains watersheds tend to have mild seasonal temperature, low topography, and fine, mostly homogenous substrate sizes; these watersheds may not follow fish and invertebrate community patterns predicted by established lotic paradigms because those paradigms tend to describe communities in either temperate or tropical regions. However, the bases of most generally accepted lotic paradigms involve evaluation of allochthonous and autochthonous contributions to lotic ecosystems via three hydrologic connectivity dimensions including vertical (hyporheic and shallow groundwater), lateral (floodplain), and longitudinal (upstream and downstream). My dissertation goals were to explore these three dimensions within Louisiana coastal plains …


Toward A Safer Transportation System For Senior Road Users, Saba Doulabi Nov 2022

Toward A Safer Transportation System For Senior Road Users, Saba Doulabi

LSU Doctoral Dissertations

Senior pedestrians and drivers (65 years and older) are among the most vulnerable road users. As the population of seniors rise, concerns regarding older adults' traffic safety are growing. The advantages of using autonomous vehicles, innovative vehicle technologies, and active transportation are becoming more widely recognized to improve seniors' mobility and safety. This behooves researchers to further investigate senior road users’ safety challenges and countermeasures. This study contributes to the literature by achieving two main goals. First, to explore contributing factors affecting the safety of older pedestrians and drivers in the current transportation system. Second, to examine seniors’ perceptions, preferences, …


The Oboe Excerpts: A Preparation Guide For Orchestral Auditions, Jana Zilova Nov 2022

The Oboe Excerpts: A Preparation Guide For Orchestral Auditions, Jana Zilova

LSU Doctoral Dissertations

This monograph presents an overview of the top ten most requested oboe orchestral excerpts. It provides young aspiring oboists with a better understanding of the pieces, along with different interpretations, to help them prepare for an orchestral audition. The beginning describes how the top ten excerpts were selected and introduces two professional oboe players who contributed to this paper. The middle section provides a background of each piece, pedagogical suggestions, and a list of recordings and books where the oboe excerpts can be found.


Compilation Optimizations To Enhance Resilience Of Big Data Programs And Quantum Processors, Travis D. Lecompte Nov 2022

Compilation Optimizations To Enhance Resilience Of Big Data Programs And Quantum Processors, Travis D. Lecompte

LSU Doctoral Dissertations

Modern computers can experience a variety of transient errors due to the surrounding environment, known as soft faults. Although the frequency of these faults is low enough to not be noticeable on personal computers, they become a considerable concern during large-scale distributed computations or systems in more vulnerable environments like satellites. These faults occur as a bit flip of some value in a register, operation, or memory during execution. They surface as either program crashes, hangs, or silent data corruption (SDC), each of which can waste time, money, and resources. Hardware methods, such as shielding or error correcting memory (ECM), …


A Study Of Indigenous North Vietnamese Ca Tru Music, And The Deities Of The Kalachakra Mandala, Daniel D'Aiuto Schultz Nov 2022

A Study Of Indigenous North Vietnamese Ca Tru Music, And The Deities Of The Kalachakra Mandala, Daniel D'Aiuto Schultz

LSU Doctoral Dissertations

Abstract

This document is in two sections. Chapter I is a study on the history, instruments and performance of Vietnamese ca trù folk music. Indigenous Asian music, especially music from Vietnam, has held an almost mystical interest for me with its links to the doctrines of Buddhism and Hinduism. Ca trù’s singular style, always sung by women in fixed ensembles, is of particular interest because of its colorful history and unique performance practices. The ca trù music of Vietnam’s northern provinces, like much Asian folk music, is considered an endangered genre.

Sources for Ca trù insights are scarce, but some …


Spam Detection Using Machine Learning And Deep Learning, Olubodunde Agboola Nov 2022

Spam Detection Using Machine Learning And Deep Learning, Olubodunde Agboola

LSU Doctoral Dissertations

Text messages are essential these days; however, spam texts have contributed negatively to the success of this communication mode. The compromised authenticity of such messages has given rise to several security breaches. Using spam messages, malicious links have been sent to either harm the system or obtain information detrimental to the user. Spam SMS messages as well as emails have been used as media for attacks such as masquerading and smishing ( a phishing attack through text messaging), and this has threatened both the user and service providers. Therefore, given the waves of attacks, the need to identify and remove …


A Field-Deployable Quartz Crystal Microbalance System For Gas Detection, Jongyoon Park Nov 2022

A Field-Deployable Quartz Crystal Microbalance System For Gas Detection, Jongyoon Park

LSU Doctoral Dissertations

Quartz crystal microbalance (QCM) has been widely studied as a mass sensing technique in laboratory environments and has shown a wide range of industrial applications such as food quality control, various forms of chemical detection, and biomolecular recognition under gas phase as well as liquid phase media. The construction of multi-sensor arrays combined with special sensor coatings enables multiple analyte detections and discrimination of multi-analyte along with statistical analysis. Despite the great sensing capabilities of QCM and growing interest in practical applications beyond the laboratory setup, most QCM studies are still performed in laboratory settings with benchtop QCM instruments. Therefore, …


Asexual Dramaturgies: Reading For Asexuality In The Western Theatrical Canon, Anna Maria Ruffino Broussard Nov 2022

Asexual Dramaturgies: Reading For Asexuality In The Western Theatrical Canon, Anna Maria Ruffino Broussard

LSU Doctoral Dissertations

Asexuality has recently gained recognition and visibility as a legitimate sexual orientation and identity standpoint that is usually defined as lacking sexual desire for any gender. Popular culture and the academy have both seen the emergence of a robust conversation about the definition and import of asexuality, recognizing the term as an umbrella concept covering an ever-diversifying array of identities. Within the nascent critical discourse on asexuality, theorists have sought to identify asexuality as a sexual orientation, to rethink our society’s sexual normativity, and to question compulsory sexuality, or the assumption that sexual desire is intrinsic to all people, thus …


Identification Of Quantitative Trait Loci (Qtls) For Resistance To Bacterial Leaf Streak: Xanthomonas Translucens Using Qtl And Association Mapping In Three Populations Of Soft Red Winter Wheat, Benjamin Tyler Meritt Nov 2022

Identification Of Quantitative Trait Loci (Qtls) For Resistance To Bacterial Leaf Streak: Xanthomonas Translucens Using Qtl And Association Mapping In Three Populations Of Soft Red Winter Wheat, Benjamin Tyler Meritt

LSU Doctoral Dissertations

Bacterial leaf streak (BLS) and black chaff, caused by Xanthomonas translucens pv. undulosa (Xtu), can be a very destructive disease of wheat, especially in the warmer, wetter areas of the Southeastern U.S. Yield losses of up to 40 percent have been recorded in some cases in southern wheat growing regions. With no effective agronomic or chemical method of disease control, identification of genetic resistance is seen as a promising solution. Three soft red winter wheat populations (GAWN, ARK-SNP, and AGS 2060- AGS 2035 DH) representative of soft red winter wheat germplasm in the southeastern U.S. developed by …


Polymer Mimetics For Soil Modeling And Detection Of Biomarkers, Md Ragib Hasan Nov 2022

Polymer Mimetics For Soil Modeling And Detection Of Biomarkers, Md Ragib Hasan

LSU Doctoral Dissertations

The population of the world is increasing day by day and is expected to reach 9.8 billion by the year 2050. The ever-increasing demand for agricultural products is putting an unprecedented strain on the world's soils as the human population continues to expand. Soil degradation caused by over-farming and the agrochemicals (fertilizers, pesticides, etc.) used in agriculture is a growing problem, although its causes remain murky. In addition, little is understood about the molecular-level interactions of substances that are subsequently introduced to soils, such as agricultural chemicals (ACs). Therefore, it is expected that these constraints may be circumvented by the …


A Performance Guide To Michael Patterson's "People Of The Land" For Baritone And Piano, Thaddeus Harm Ennen Nov 2022

A Performance Guide To Michael Patterson's "People Of The Land" For Baritone And Piano, Thaddeus Harm Ennen

LSU Doctoral Dissertations

The purpose of this document is to supply a comprehensive performer’s guide to Iowa composer, Dr. Michael Patterson’s, People of the Land, an eight song, song cycle for baritone and piano, set to poetry by Iowa poet James Hearst. This song cycle was personally commissioned to fulfill a need in the American song cycle literature on the topic of farming and more specifically Iowa farmers. The poetry of James Hearst, farmer and poet, has never been previously set in a song cycle.

People of the Land tells the story of an Iowa farmer from the beginning to end of …


Hydrogeologic Investigation Of A Covered Karst Terrain, Joseph Peter Honings Oct 2022

Hydrogeologic Investigation Of A Covered Karst Terrain, Joseph Peter Honings

LSU Doctoral Dissertations

Increasing demand for water for agricultural use within the Dougherty Plain of the Southeastern United States has depleted surface water bodies. In karstic landscapes, such as the Dougherty Plain in southwest Georgia where the linkages between surface and ground waters are close, there is a need to understand the physical characteristics of the subsurface that allow these close linkages. Having a better understanding of the subsurface characteristics will aid numerical modeling efforts that underpin policy decisions and economic analyses. Two common features on this karstic landscape are draws and geographically isolated wetlands. Using LiDAR, aerial imagery, and ground-penetrating radar, this …


Investigating The Relational Element Of Trust In Teacher-Principal Relationships: An Autoethnographic Case Study, Angela Bradley Oct 2022

Investigating The Relational Element Of Trust In Teacher-Principal Relationships: An Autoethnographic Case Study, Angela Bradley

LSU Doctoral Dissertations

This autoethnographic case study was designed to investigate the relational aspect of trust, a characteristic of servant leadership, in the teacher-principal relationship. This trusting bond is an often overlooked, foundational element of a school’s success. I examined the role that trust plays in enhancing a school’s culture and how trust is established and maintained among one principal and teachers under my supervision. In addition, as researcher, I sought to uncover specific indicators that trust was present on a school campus. Finally, I sought to examine trust’s effects on collaboration and organizational commitment.

Through weekly reflections, I sought to examine my …


Physical To Cyber: A Case Study Of The Print And Digital Literacy Of Burgeoning Older Adult Learners, Laura Elizabeth Williams Oct 2022

Physical To Cyber: A Case Study Of The Print And Digital Literacy Of Burgeoning Older Adult Learners, Laura Elizabeth Williams

LSU Doctoral Dissertations

This intrinsic single case study explored the ways in which two older adult burgeoning literacy learners in a capital city in the U.S. Gulf South utilized the skills of print literacy and digital literacy both together and apart. This study was an investigation of print and digital literacy, individually and combined, in order to examine the way older adult burgeoning literacy learners used one kind of literacy (print) to develop the other (digital). Using semi-structured interviews, observations, and literacy journals, participants’ perceptions were explored. Findings included that fully literate older adults used their literacy to enact and maintain social connections, …


The Risks Posed By Mosquito Ultra-Low Volume Applications To Procambarus Clarkii Production, Timothy Mcnamara Oct 2022

The Risks Posed By Mosquito Ultra-Low Volume Applications To Procambarus Clarkii Production, Timothy Mcnamara

LSU Doctoral Dissertations

Mosquito abatement has received much scrutiny due to concerns about the impacts of control applications on non-target organisms. In Louisiana, a great deal of this concern has come from crawfish farmers claiming mosquito abatement applications have damaged crawfish production. To determine which mosquito abatement practices and products pose a risk to crawfish production, we conducted a series of studies examining mosquito abatement practices in the vicinity of crawfish production fields and the impacts of common mosquito abatement product exposure on crawfish health and production. We found that mosquito ULV applications are the most likely to result in exposure to crawfish …


Overcoming Gifted Student Underachievement Through Teacher Best Practices, Samantha Simmons Webre Oct 2022

Overcoming Gifted Student Underachievement Through Teacher Best Practices, Samantha Simmons Webre

LSU Doctoral Dissertations

The goal of this study is to collect the best practices being utilized by gifted teachers affecting change amongst their gifted underachieving students. Data collected will explore trends deemed significant among the successful best practices being utilized by academically gifted certified teachers.

The researcher will administer surveys, conduct interviews, and classroom observations to collect data from a sample of participants who are currently employed as academically gifted certified teachers. This study will focus on these academically gifted certified teacher’s definitions and recognition of underachievement, identified causes for underachievement, best practices employed to re-engage underachieving students, as well as perceptions of …