Digital Commons Network^™

Population Genomic Characterization Of Cercospora Janseana On Rice In The Southern United States, Jacob Searight

LSU Master's Theses

Cercospora janseana is the causative agent of narrow brown leaf spot (NBLS). Effort had been undertaken since the 1940’s to control this disease through resistance breeding in the Southern United States. However, a severe epidemic of NBLS in 2006 inspired renewed focus on managing this disease. One tool for managing this disease has been identified among resistant cultivars, the CRSP-2.1 resistance locus to NBLS. One thing limiting the investment and deployment of CRSP-2.1, and other unknown resistance genes, is the historical observation that resistance to NBLS rapidly breaks-down in the field. Together, the rapid breakdown of resistance to NBLS …

Environmental Controls On Carbon Biogeochemistry In Aquatic Systems, Lee Potter

LSU Master's Theses

Carbon dioxide (CO₂) outgassing from inland waters is a small but critical component of the global carbon cycle that is currently not well constrained. This thesis is composed of three interrelated studies with an overarching goal to further determine environmental factors impacting carbon dynamics in rivers and lakes. These studies utilized water samples and in situ measurements of pCO₂ and ambient water parameters from the Lower Mississippi River at Baton Rouge and University Lake in Baton Rouge Louisiana, USA collected between January 2021 and August 2022. Additional Meteorological and hydrological data were download from public sources. Results …

Self-Powered Lights For Photosynthetic Cultures, Maria T. Gutierrez-Wing, Jin-Woo Choi

College of Agriculture Patents

Various examples of methods and systems are provided for increasing productivity of one or more photosynthetic cultures via self-powered energy output systems. In one example, a system includes a waterproof casing and an energy output module enclosed within the waterproof casing. The waterproof casing is configured to be neutrally buoyant in an enclosure comprising the one or more photosynthetic cultures. In another example, a method includes placing a self-powered energy output system within an enclosure, the self-powered energy output system being neutrally buoyant within the enclosure. The method further includes causing turbulence within the enclosure, and the self-powered energy output …

Dynamics Of Bottlebrush Polymers In Solution By Neutron Spin Echo Spectroscopy, Karin J. Bichler, Bruno Jakobi, Dirk Honecker, Laura R. Stingaciu, Thomas K. Weldeghiorghis, James H.P. Collins, Gerald J. Schneider

Faculty Publications

We present dynamical and morphological studies on poly(dimethylsiloxane) (PDMS)-based bottlebrush polymers in solution. A combination of small-angle neutron scattering (SANS), pulsed field gradient nuclear magnetic resonance (PFG NMR), and neutron spin echo (NSE) spectroscopy was used to identify structural changes inherent in changing the side-chain length while keeping the backbone constant. These morphological changes are mirrored in the diffusion coefficient determined by PFG NMR, resulting in two coefficients for the elongated and one for the more spherical sample. Faster motions are tracked by NSE using the advantage of time- and length-scale resolutions with the diffusion coefficient predetermined by PFG NMR. …

Defining Understudied Mechanisms Of Potassium Ion Flux In The Insect Nervous System, Rui Chen

LSU Doctoral Dissertations

To identify novel insecticide target sites that can address the evolution of insecticide resistance, our group has tested the insecticidal potential of two potassium flux pathways: potassium-chloride (K+/Cl−) cotransporter (KCC) and inward rectifier potassium (Kir) channels. GABAergic signaling is the cornerstone of fast synaptic inhibition for neural signaling in arthropods; thus, the γ-aminobutyric acid (GABA)-receptor-chloride-channel (GRCC) complex has been a longstanding target for insecticides. Despite the importance to neuronal homeostasis, the upstream mechanisms enabling GRCC function are poorly defined. The data presented in this dissertation provide strong support that KCC is an essential ion transport system for proper neural function …

Languages Of Reform: Populist Revolution Or Middle-Class Progressivism?, Timothy Vest Klein

LSU Doctoral Dissertations

Populists and Progressives around the turn of the 20^th century had similar reform goals and many of the same foes. Both wanted to expand the power of the federal government to counter corporate monopolies which were dominating the nation’s economy and political system. In the early 1900s, Progressives enacted numerous reforms that were championed by Populists, including regulating railroads and other large corporations, breaking-up monopolies, implementing a graduated income tax, among other reforms. With so much agreement on policy, why did Populists and Progressives actively work against one another in the 1890s?

Part of their antagonism came from their …

A Machine Learning Approach To Robotic Additive Manufacturing Of Uv-Curable Polymers Using Direct Ink Writing, Luis A. Velazquez

LSU Master's Theses

This thesis presents the design and implementation of a robotic additive manufacturing system that uses ultraviolet (UV)-curable thermoset polymers. Its design considers future applications involving free-standing 3D printing by means of partial UV curing and the fabrication of samples that are reinforced with fillers or fibers to manufacture complex-shape objects.

The proposed setup integrates a custom-built extruder with a UR5e collaborative manipulator. The capabilities of the system were demonstrated using Anycubic resin formulations containing fumed silica (FS) at varying weight fractions from 2.8 to 8 wt%. To fully cure the specimens after fabrication, a UV chamber was used. Then, measurements …

Non-Compliance, Non-Additionality, And Disadoption: Insights Into Challenges In Agricultural Conservation Programs, Santosh Pathak

LSU Doctoral Dissertations

Agricultural conservation programs are a principal vehicle of the US federal government to combat environmental externalities arising from resource-intensive agricultural production. However, non-compliance, non-additionality, and disadoption issues often impede the sustainability goals envisioned by such programs. This dissertation consists of three essays that shed light on key challenges facing working lands programs, such as the Environmental Quality Incentives Program (EQIP) and the Conservation Stewardship Program (CSP).

In the second chapter, I study the non-compliance rate in cost-share contracts between farmers and the Natural Resources Conservation Service (NRCS). Using a suite of panel data methods and an instrumental variable approach, I …

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, …

Are Insulin Sensitivity And Β-Cell Function Associated With Adverse Pregnancy Outcomes Among Women With Gestational Diabetes?, Gang Hu

Population and Public Health Science Faculty Publications

No abstract provided.

Paraquat-Resistant Italian Ryegrass (Lolium Multiflorum) Confirmed In Louisiana, Alphonse B. Coco Iii

LSU Master's Theses

Paraquat is the only herbicide labeled for postemergence control of Italian ryegrass in sugarcane. In 2017, sugarcane farmers in Louisiana reported Italian ryegrass control failures with paraquat applications. Seeds were collected from sugarcane fields in White Castle, St. Gabriel, and Bunkie, Louisiana where control was not achieved (reduced susceptibility). Additionally, Italian ryegrass seeds were collected from a sugarcane field in Welcome, LA with a history of paraquat use and with no reported control issues (susceptible population). A dose-response study was conducted at the Louisiana State University Agricultural Center’s Sugar Research Station in February 2021 and was repeated in November 2021. …

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 …

Archean Metamorphosed Ultramafic Rocks And Chromitites From The Beartooth Mountains, Montana, Usa: Insights Into Mantle Geochemistry And Tectonics, Rachel M. Gnieski

LSU Master's Theses

Metamorphosed ultramafic rocks and associated chromitite pods in the eastern Beartooth Mountains, Montana (USA) provide a window into the tectonic evolution of the Archean northern Wyoming Province. Meta-ultramafic rocks occur with a variety of metasupracrustal rocks as xenoliths in an extensive 2.8 Ga suite of TTG (meta)plutonic rocks. The origin of the ultramafic rocks is obscured by an upper amphibolite-to-greenschist facies overprint. Major element analyses (XRF, wt. %) of meta-ultramafic host rocks show SiO₂ from 40.53-50.37, MgO from 15.33-45.25, TiO₂ from 0.07-0.62, Al₂O₃ from 1.25-10.62, and Fe₂O₃(t) from 8.06-14.54. Total alkali …

Assessing Turgor Loss Point In Bottomland Hardwood Trees Using Leaf Spectroscopy, Alexandra M. Eisley

LSU Master's Theses

Climate change is expected to radically alter our planet’s forests, with higher frequencies of drought- and flood-induced mortality events posing a challenge for forest managers and biologists. Research into the factors underlying plant tolerance to environmental stressors is therefore gaining popularity for incorporation into projective and earth system modeling using remote sensing measures. Leaf turgor loss point (TLP) is a key trait associated with drought tolerance among plants and is defined as the water potential at which leaf turgor pressure reaches zero, causing wilting. Here, I investigated patterns of TLP across the landscape and its role as an indicator of …

Impact Of Rma’S Projected Price On Prevent Planting Claims, Nicolas Enrique Alvarez Mena

LSU Master's Theses

This research studies the presence of ex-post moral hazard in the prevent planting provision from the crop insurance program in cotton, corn, and soybeans for the Plains Region and Southeast Regions of the U.S. Three fixed effect models are developed using the proportion of prevent plant acres as the dependent variable, as well as weather, input price, expected harvest price and a break-even point for the independent variables. In addition, a fourth fixed effect (FE) model is introduced using the logit transformation and the same variables as in previous models. The results show the number of PP claims has been …

Role Of Cd38 In Pulmonary Host Defense Against Gram-Negative Pneumonia, Xiaoqian Shan

LSU Master's Theses

The Gram-negative bacterium, Klebsiella pneumoniae, is a major cause of hospital-acquired pneumonia in the U.S. In particular, the dramatic increase in carbapenem-resistant K. pneumoniae infections poses a serious threat to the public health both in the United States and worldwide. Clearance of bacteria in the lungs depends on effective pulmonary immune response. It may be possible to design improved therapies that augment host immune responses while attenuating excessive pulmonary inflammation through modulation of key innate immunity molecules during pneumonic infections. Cluster differentiation CD38 (CD38) has been detected on the surface of many immune cells or intracellular compartments, acting as …

Searching For The Soldier Pheromone: Behavioral Effects Of Soldiers And Soldier-Produced Chemicals In The Formosan Subterranean Termite, Coptotermes Formosanus (Blattodea: Rhinotermitidae)), Joseph Mccarthy

LSU Master's Theses

The Formosan subterranean termite, Coptotermes formosanus, is a eusocial insect and an invasive urban pest. Colonies function through a division of labor among castes (i.e., queens and kings, workers, and soldiers). Though soldiers are energetically expensive to maintain, C. formosanus has a relatively large soldier caste (~10% of the colony). Soldiers are physically unable to collect food or build tunnels but are regularly found with foraging workers. In some species, soldiers influence the worker foraging behavior. In C. formosanus, aside from defense, the roles soldiers play remains unknown. In this study, we determined if soldiers influence …

Fractal Like Snowflakes Generated By Non-Contractive Function Systems, William H. Kelly Iii

LSU Master's Theses

At the heart of this thesis is the examination of a non-contractive iterative function system T on the Hausdorff metric space of all compact subset of ℝ . Despite the absence of an 2 attracting fixed point, an examination reveals the appearance of fractal-like shapes (snowflakes) when applying the Barnsley’ random walk method to study the iterative sequence ��ⁿ(0) (�� ∈ ℕ) for �� = ��¹ ∪ ��² ∪ ��³, where ��₁(��) = ����, ��₂(��) = ���� + ��, and ��₃(��) = ���� - ��, and �� = …

Enabling The Human Perception Of A Working Camera In Web Conferences Via Its Movement, Anish Shrestha

LSU Master's Theses

In recent years, video conferencing has seen a significant increase in its usage due to the COVID-19 pandemic. When casting user’s video to other participants, the videoconference applications (e.g. Zoom, FaceTime, Skype, etc.) mainly leverage 1) webcam’s LED-light indicator, 2) user’s video feedback in the software and 3) the software’s video on/off icons to remind the user whether the camera is being used. However, these methods all impose the responsibility on the user itself to check the camera status, and there have been numerous cases reported when users expose their privacy inadvertently due to not realizing that their camera is …

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, …

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, …

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

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 …

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.

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 …

Design, Synthesis, And Characterization Of Nqo1-Activatable Luminescent Probes, Ovini Vionika Weeratung Kankanamge

LSU Doctoral Dissertations

Being among the top ten causes of death, cancer has constantly been able to grab the attention of researchers all around the world. While several treatment methods prevail to cure cancer, the seriousness of this medical condition requires continuous work in the development of novel treatments as well as scientific advancements in order to achieve early detection of the disease. Luminescence imaging is an emerging field in both diagnosis of diseases, as well as a means to provide guidance in clinical surgeries. While there exist only a few contrasting agents approved by the Food and Drug Administration, the need for …

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 …

From Biowaste To Product: The Functionalization Of Biochar For Agricultural And Environmental Applications, Baoyue Zhou

LSU Doctoral Dissertations

Biochar is a porous carbonated substance that is manufactured through pyrolysis of biomass feedstocks in an oxygen-deficiency environment. The production of biochar from agricultural waste materials provides a potential solution for eliminating pollution while improving carbon sequestration. While biochar is shown to provide multiple benefits to soil health and fertility, its use in environmental remediation has been hampered by its low affinity for hazardous anionic species and the difficulty in isolating from water phase. To overcome these obstacles, various efforts have been made to modify biochar surface chemistry and morphology.

Fe/Mg co-doped biochar composites from sugarcane harvest residue were prepared …

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 …

The Role Of Kisspeptins In Trophoblast Cell Dynamics: Comparative Studies Using The Horse And The Preeclamptic-Like Bph/5 Mouse As Animal Models, Viviane Cristine Leite Gomes

LSU Doctoral Dissertations

Kisspeptins, a family of small peptides derived from the Kiss1 gene, have been described in trophoblast cell dynamics, placentation, and pregnancy outcomes. Furthermore, many other physiological functions have been attributed to kisspeptins, including neuroendocrine regulation of puberty and cyclicity, and peripheral and central regulation of metabolism and adipogenesis. Herein, studies were performed in the Blood Pressure High Subline 5 (BPH/5) mouse and the horse to further investigate the role of kisspeptins in pregnancy. The BPH/5 mouse recapitulates the main features of human preeclampsia (PE), a hypertensive disorder of pregnancy associated with maternal and fetal adverse outcomes. BPH/5 phenotypic characteristics include …