Digital Commons Network^™

Genetic Characterization Of Resitance To Frogeye Leaf Spot Of Soybean, Gabriel D. Munoz Herrera

LSU Master's Theses

Cercospora sojina is the causal agent of the fungal disease frogeye leaf spot (FLS) in soybeans. Management of this disease consists of foliar application of fungicides and the use of resistant cultivars. However, fungicide resistance has been detected in C. sojina populations and characterization of host resistance genes is relatively limited. To overcome the latter obstacle, we aimed to identify novel resistance genes using quantitative image analysis of the SoyNAM population. Two image analysis workflows using ImageJ and PlantCV were optimized and implemented to increase reproducibility and reduce subjectivity. The quantitative measurements included disease severity, lesion count, and average lesion …

Programming The Properties Of Branched Polymers Through Precision Architectures, Michael R. Dearman

LSU Master's Theses

The glass transition of branched polymers is determined by multiple structural parameters that dictate their inter- and intramolecular interactions, and ultimately, their molecular packing in the amorphous phase. Here we examined the impact of side chain length, backbone length, molecular weight composition, and topology on the glass transition behavior of bottlebrush polymers. Through examining precision bottlebrush polymer libraries (PBP, ĐSC = 1.0), we find the infinite molecular weight Tg is reached at a specific brush length after which the effect of the side-chain length dominates. Being a factor more dominant than the backbone, side-chain length affects the Tg of bottlebrush …

The Limits Of Financial Equity: The Federal Reserve, The Depression Of 1921, And The End Of Wilsonian Progressivism, Terril Hebert

LSU Master's Theses

The Limits of Financial Equity: The Federal Reserve, the Depression of 1921, and the End of Wilsonian Progressivism is an examination of monetary policy and centralized macroeconomic planning in the American economy during the inflationary spiral of the 1910s that culminated in the Depression of 1921. Put forward for consideration is the successful populist campaign for agricultural credit equity by the burgeoning Federal Reserve System; set against a backdrop of intentional inflation, world and domestic citizens competed against as the price and supply chain distortions perpetuated by the policing of American commerce by the Food Administration, A. Mitchell Palmer’s Department …

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 …

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 …

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. …

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 …

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 …

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 …

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 …

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 …

Review Of Structural Color In The Genus Chrysochroa Dejean, 1833 (Coleoptera: Buprestidae), Able Chow

LSU Master's Theses

The jewel beetles, (Coleoptera: Buprestidae Leach, 1815), is the eighth most speciose coleopteran family, with the majority of its members possessing diverse bright, saturated structural coloration of multilayer origin. This study focuses on the genus Chrysochroa Dejean, 1833, which includes some of the most brilliantly and charismatically colored buprestid species. While members of Chrysochroa are prised by entomologists amateurs and professional and are well-represented in museum collections, the evolution and ecology of their structural color remain underexplored. Twenty-eight select taxa including exemplars from all 13 subgenera of Chrysochroa were investigated to provide an overview of the objective optical properties and …

Environmental Educators’ Perceptions Of Inaugural Louisiana State Department Of Education Environmental Education Standards And Accompanying Environmental Education Endorsement Plan: A Multiple Case Study Approach, Abigail Greer

LSU Master's Theses

Increasing environmental literacy through environmental education is an integral approach to fighting many of the environmental challenges facing Louisiana. The State Department of Education in Louisiana has released two initiatives to increase environmental literacy in the state while incorporating nonformal environmental education into formalized k-12 education. The first initiative is a set of Key Principles and Concepts (KPCs) in environmental education, which is aimed at providing standards to nonformal environmental educators in Louisiana. The second initiative, the Louisiana Environmental Education Advancement Plan (LEEAP), accompanies the KPCs and provides an opportunity for nonformal environmental education organizations to achieve endorsement through partnership …

Color, Culture, And The Implications For Emotional, Cognitive, And Behavioral Reactions, Renee Lucas

LSU Master's Theses

Color plays a significant role in life, influencing how we perceive things, how symbols change in meaning, how brands, logos, and pictograms are communicated, as well as how our emotions are perceived and how our moods are affected. For designers, advertisers, and visual communicators, color is crucial because it has a big impact on how people perceive, relate to, and value an image or advertisement. There are many factors that play a role when people develop their personal color interpretations – one being culture. The purpose of this study is to investigate the links between culture, color, and individuals’ cognitive, …

Snapshots Of Coastal Ecology During Glacial And Deglacial Intervals: A Multiproxy Assessment Of Northern Gulf Of Mexico Sediment Cores, Kendall Emilie Brome

LSU Master's Theses

Terrestrial ecosystems along exposed continental shelves during times of relatively low sea level and glaciation are rarely preserved due to the mechanically erosive nature of marine transgression and regression. In this study, I investigate the geochemical and palynological characteristics of two well-preserved sites in the northern Gulf of Mexico (NGOM) to determine the ecologic settings and subsequent mechanisms of preservation in this region. Both sites contain preserved terrigenous sediments of previously exposed coastal margins; the first is located at the Alabama Underwater Forest (~13 km south of Gulf Shores, AL, at ~15 mbsl), and optically stimulated luminescence dates to 72–56 …

Setting Up Shop Down South: Gay Visibility And Identity Formation At A New Orleans Bookstore, Katelyn N. Spencer

LSU Master's Theses

Looking specifically at the South’s first gay bookstore, Faubourg Marigny (FM) Books, this thesis will connect the existence of gay literature and space as impetuses of gay community identity within New Orleans. It will use the political, social, and cultural histories of the 1970s through the 2010s to contextualize the gay bookstore as a microcosm of its time and location. In doing so, it will examine how FM Books’ New Orleans location affected its function and its relationship with its community. It will also analyze how the bookstore fit into the city’s history of social tradition and aversion to flagrant …

Improvements To The Automatic Calibration Of Digital Focusing Color Schlieren Systems, Robert C. Frazee

LSU Master's Theses

As a diagnostic method, Schlieren imaging offers the unique ability to visualize flows with a completely non-intrusive method. By visualizing small changes in the refractive index of a fluid, Schlieren imaging is able to visualize changes in temperature, pressure, and composition. While historic Schlieren methods have been limited to providing largely qualitative information, modern Schlieren methods are able to extract quantitative information from flow phenomena. This is possible through either Background Oriented Schlieren (BOS) or Digital Focusing Color Schlieren (DFCS) methods. While BOS is relatively flexible, it requires a large amount of computational effort to process each frame of captured …

We Are All Connected, Behnoush Tavasolinia

LSU Master's Theses

Upon personal reflection, I have discovered that economic, cultural, and social issues have become very important in my life. As an Iranian graphic designer, I used current events and responded to Iranian stories to reflect that people’s problems anywhere in the world affect other people’s lives worldwide. My thesis investigation aims to reveal the global connection with commodities by focusing on Iran’s economic inflation to create a conceptual and visual representation of impacted consumables. Persian rugs and tile designs are the centers of the culture and symbols of the Iranian people. I used graphic design to illustrate tiles utilizing economic …

Application Of Direct Feedback Tunable Diode Laser Absorption Spectroscopy Within A Hybrid Rocket Combustor, Connor Becnel

LSU Master's Theses

With interest in space travel and space-related science increasing in recent years, significant efforts to reduce the cost and increase the safety of rocket motors have become commonplace. Liquid rockets are currently the most commonly used system, but there is interest in the reduced complexity of hybrid rockets. For these hybrid rocket motors to become the norm, extensive research on their complex boundary layer combustion needs to be performed. Modeling these hybrid systems is of much interest to companies developing rocket motors; ultimately, small-scale experiments will help validate their behavior. This paper covers the application of a near-infrared tunable diode …

Narcissism And Risk-Taking For Others, Tyler B. Cowley

LSU Master's Theses

While prior findings demonstrate that narcissists are excessively risk-seeking for themselves, research does not yet understand if their risk-seeking behaviors extend to others as well. This paper examines the role of narcissism in risk-taking on behalf of others. I hypothesize that narcissists will take more risks when deciding for others because they lack empathy and perspective taking. Therefore, narcissists are more likely to take risks based on their personal preferences, rather than the recipient’s desires. To test my hypotheses, participants completed the Balloon Analogue Risk Task (BART) for themselves, another individual, and an anonymous individual, followed by completing the Narcissistic …

Immunohistochemical Localization Of Kisspeptin And Its Receptor In The Equine Ovary, Bryce M. Gilbert

LSU Master's Theses

Kisspeptin is recognized for its role as the gatekeeper of reproduction in most mammalian species. However, its role in regulation of reproduction at the ovarian level is poorly understood in the horse. In this study, ovaries from follicular phase, luteal phase, anestrous period, and mares treated with ECP-sulpiride were subjected to immunohistochemistry to characterize kisspeptin-10 (Kp10) and its receptor (Kiss1r) protein expression throughout each reproductive stage and follicle type. Kisspeptin and receptor staining was detected in all follicle types (primordial, preantral, and antral) throughout all reproductive stages, as well as oocytes, corpora lutea, and ovulation fossa. The pattern of Kp10 …

The Effect Of Word-Learning Biases On Early Vocabulary Acquisition In Young Children On The Autism Spectrum, Claire C. Bourgeois

LSU Master's Theses

Background: Vocabulary composition and word-learning biases are closely interrelated in typical development. Such word-learning biases are influenced by perceptually and conceptually salient word features, including imageability, concreteness, iconicity, and attention to shape. Autistic children often have delayed language acquisition, but there is currently little research examining the underlying mechanisms autistic children use to acquire words. The current study aimed to examine the noun composition of autistic children across a range of vocabulary sizes by examining associations between expressive noun vocabulary size and imageability, iconicity, concreteness and evidence for the shape bias, and to examine whether these patterns differ from their …

Device Free Indoor Localization Of Human Target Using Wifi Fingerprinting, Prasanga Neupane

LSU Master's Theses

Indoor localization of human objects has many important applications nowadays. Proposed here is a new device free approach where all the transceiver devices are fixed in an indoor environment so that the human target doesn't need to carry any transceiver device with them. This work proposes radio-frequency fingerprinting for the localization of human targets which makes this even more convenient as radio-frequency wireless signals can be easily acquired using an existing wireless network in an indoor environment. This work explores different avenues for optimal and effective placement of transmitter devices for better localization. In this work, an experimental environment is …

Verb Diversities Of Children With And Without Developmental Language Disorder: A Study Of Language Samples, Caitlyn J. Kearns

LSU Master's Theses

Background: There have been numerous studies that have researched word learning in children with Developmental Language Disorder (DLD). These studies have found that children with DLD present with higher vocabulary deficits compared to their typically developing (TD) peers. Many of these studies’ results suggest that verb learning is the most difficult word type to comprehend in early language development for both TD children and children with DLD. This current study aims to examine verb use in children with and without DLD and to specifically examine their usage of GAP verbs. Methods: Participants included 36 children, 18 TD and 18 DLD …

Utilization Of A Gravity Model To Determine The Impact Of Covid-19 In Us Bilateral Trade, Dacia Lopez Lopez

LSU Master's Theses

In April 2022, the United States traded with approximately 233 countries. Exports and imports of goods and services represent 11.73% and 14.58% of U.S. GDP respectively. Because of that, U.S. bilateral trade is important. COVID-19 impacted the economy and trade in different ways as supply and demand changes. The objective of this study is to determine the impact of COVID-19 in U.S. bilateral trade using an augmented gravity model and panel data from 20 U.S. partner countries and the United States over 24 quarters, from 2015 to 2021.

To accomplish these objectives, a gravity model was used and Random effects …

Understanding Motivations Among Sustained Cooperative Extension Partners For Obesity Prevention In Rural Louisiana, Catherine R. Losavio

LSU Master's Theses

Louisiana consistently has one of the highest rates of obesity in the nation with higher concentrations of obesity in many rural parishes (i.e., counties). Due to over a century of visibility and engagement in rural communities, Cooperative Extension (Extension) is uniquely poised to reach remote rural communities disproportionately impacted by obesity. As Extension increases its use of community coalitions and implements its new National Framework for Health Equity and Well-Being, understanding motivations and communication preferences among long-term rural coalition partners for obesity prevention and health promotion has become essential for duplicating successful local-level policy, system, and environmental (PSE) changes. This …

Influence Of Hesperidin On The Physico-Chemical, Microbiological, And Sensory Characteristics Of Frozen Yogurt, Roberto Antonio Cedillos Hernández

LSU Master's Theses

Frozen yogurts contain yogurt culture bacteria which might impart health benefits to its consumers. Global frozen yogurt market sales are expected to grow 4.8% by 2028 which represents an important opportunity for the industry, consumers, and researchers. Polyphenols are metabolites found in plants which have antioxidant and anti-inflammatory properties and might prevent chronical diseases such as cancer, diabetes, and cardiovascular diseases. The objective of this study was to elucidate the effect of the polyphenol hesperidin on the physico-chemical, microbiological, and sensory characteristics of frozen yogurts. Hesperidin was incorporated in frozen yogurt at three concentrations (500, 250 and 125 mg/90g of …

Effect Of Fine Aggregate And Pva Fiber Content On The Properties Of Metakaolin-Based Engineered Geopolymer Composites, Ruwa Abufarsakh

LSU Master's Theses

The mechanical and physical properties of novel metakaolin (MK) based Engineered Geopolymer Composites (EGCs) consisting of locally available river sand (RS) or manufactured microsilica sand (MS) reinforced with polyvinyl alcohol (PVA) fiber were studied. Plain geopolymer (GP) binder, GP mortars, and fiber-reinforced composites were also studied. Aspects of the material composition that were investigated in this study include binder composition, aggregate type, and PVA fiber content. Per the compressive strength results, GP mortars presented greater compressive strength than GP binder where the GP mortars manufactured with lower water to solids ratio exhibited greater compressive strengths. Furthermore, the incorporation of PVA …

The Impact Of Social Support Sources On Lgbtq Adolescents, Kaitlyn C. Mccauley

LSU Master's Theses

Research demonstrates that adolescents social support plays an important role in protecting against adverse events (e.g., Brewin & MacCarthy, 1989; Muzik et al., 2017). LGBQ adolescents have been shown to experience greater adverse experiences such a daily microaggressions and higher rates of both childhood adversity (Baams, 2018) and peer victimization (Kosciw et al., 2014). Increased stressors often lead to poorer outcomes in this population. Social support research for adolescents has shown that different sources of social support have shown to buffer these reported issues (e.g., greater parent and peer support buffers suicidal ideation, Fredrick et al., 2018). Studies with LGBQ …