Digital Commons Network^™

Institutional Rhetoric And Campus Reactions: A Multi-Method Case Study Exploring University Communication And Social Responsibility In A Racial Crisis, Rockia K. Harris

LSU Doctoral Dissertations

This case study explores how an institution in the southeastern conference (SEC) responded to racial reckonings before and after the 2020 murder of George Floyd, how students came to perceive the institution's responses and commitment to diversity and inclusion. To understand this phenomenon beyond apologia and image repair theory, the discourse of renewal theoretical framework and university social responsibility guides this dissertation. This work fills a gap in the literature on crisis communication in response to racism in higher education spaces. Using critical discourse analysis and an open-ended survey, this dissertation further explores the idea of social responsibility of institutions …

Nonlinear Optical Studies At Surfaces And Interfaces, Mojgan Dehghani

LSU Doctoral Dissertations

Nonlinear optical studies have revealed that surfaces and interfaces possess unique optical properties due to the lack of inversion symmetry. These properties are significantly different from those of the bulk material. Second harmonic generation (SHG), a second-order nonlinear optical phenomenon, has emerged as a surface-specific technique to study these unique properties. The powerful selection rule allows generation of second harmonic light only in the bulk of noncentrosymmetric media and the regions with broken inversion symmetry, including surfaces and interfaces. The generated second harmonic provides significant information on the electronic and structural properties of the microscopic surface layer at the boundary …

Size Effects In Additively Manufactured Inconel-718 Thin Elements And Cellular Structures, Reem Abdelkarim Abo Znemah

LSU Doctoral Dissertations

A current focus in the additive manufacturing (AM) research community is the production of complex shaped metallic parts and cellular structures. Many researchers went on analyzing and simulating these structures without considering the effect of the element thickness and heterogeneous printing parameters on the resulting material behavior. To advance the application of laser powder bed fusion (LPBF), an AM process, in producing Inconel718 (IN718) complex shaped parts and cellular structures, this study aimed to investigate the effect of thin-walled elements thickness on the mechanical characteristics of both the individual elements and overall cellular structure. A multiscale experimental evaluation of the …

Exploration Of Efficient Dewatering Methods In Stimulus-Responsive Hydrogels And Their Potential For Desalination, Weiliang Sun

LSU Doctoral Dissertations

Addressing global freshwater scarcity is a pressing challenge, and desalination has emerged as a viable solution to generate high-quality water without compromising natural freshwater ecosystems. In comparison to conventional desalination methods such as thermal distillation and membrane-based processes, hydrogels offer distinct advantages including strong water absorption, water retention, well-defined pore structures, customizable functional groups, and responsive properties to external stimuli. These unique characteristics position hydrogels as promising candidates for water treatment applications. Hydrogel-based desalination involves the utilization of hydrogels to absorb water from saltwater, and then discharge low-concentration solutions to obtain reclaimed water. The fundamental principle underlying the desalination ability …

Women's Interracial Friendships: Cultivating Coalitional Possibilities Across Difference Through Dialogue, Akie Fukushige Wenk

LSU Doctoral Dissertations

In my dissertation, I thread through the macro-structure as well as micro-operations of hegemonic ideologies, namely white-supremacist capitalist cis-hetero patriarchy (hooks, 1995, Valdes, 1996), that has historically plagued the United States, eventually gaining a global reach over time. I center interracial friendship between Black and White cis-women, where I locate coalitional possibilities that begin at the grassroots level. I situate this interracial relationship within the socio-ecological system where the personal meets the social (including racialized backgrounds). I use a series of analogies to equate these ideologies as toxins in the air, water, and soil. Soil is where we can work …

Tissue Resident Regulatory T Cells And Immunopathology During Influenza Infections, Michael Mcgee

LSU Doctoral Dissertations

Influenza (flu) virus infections are a leading cause of respiratory illness. Globally there are approximately 290,000-650,000 deaths and 3-5 million cases of severe illness during the average flu season. Severe flu infection is associated with the combination of a strong pro-inflammatory and weak anti-inflammatory response. Regulatory T cell subsets suppress pro-inflammatory responses during flu infection, with production of the immunomodulatory cytokine IL-10 playing a critical role in this process. Tissue resident regulatory T cell subsets are maintained within nonlymphoid tissues and are optimally positioned to suppress localized pro-inflammatory responses. However, knowledge of the signaling pathways regulating the development of tissue …

Neural Mechanisms Of Resiliency And Susceptibility After Repeated Social Defeat, Christy R. Wayne

LSU Doctoral Dissertations

Social defeat is a powerful experience leading to drastic changes in physiology and behavior, many of which are negative. For example, repeated social defeat in vertebrates results in reduced reproductive success, sickness, and behavioral abnormalities that threaten individual survival and species persistence. However, little is known about what neural mechanisms are involved in determining whether an individual is resilient or susceptible to repeated social defeat stress. I used a resident-intruder experiment in the African cichlid fish, Astatotilapia burtoni, to create and investigate the behavior and neural correlates of these two opposing groups. Resilient fish used both searching and freezing behaviors …

Sportsman's Paradox: Conservationism And Social Progress In Modern Louisiana, Jacob T. Gautreaux

LSU Doctoral Dissertations

Over the nineteenth and early twentieth centuries, sportsmen increasingly identified Louisiana as a destined paradise due to the abundant flora and fauna. Confirmed in the legendary visits of Theodore Roosevelt in the early 1900s, the conception soon served a dual purpose as individuals like the Tabasco Sauce patriarch, E. A. McIlhenny, coopted the visualization as a lure for business investment into the nascent industrial interests within the coastal region of the state. However, it should be noted that in the 1930s and beyond, cultural conservationists like McIlhenny and Caroline Dormon preserved elements of under-documented cultures throughout the state, although usually …

Media Coverage Of Non-Ideologically Motivated Mass Shootings Versus Ideologically Motivated Mass Shootings And How The Media Affects College Students' Perceptions Of Mass Shootings, Jennifer L. Larose

LSU Doctoral Dissertations

While much is known about how the media covers mass shootings within the United States and how this coverage impacts the public, much remains unknown about the media and international mass shootings. To address this gap this dissertation examines the relationship between the media coverage of ideological and non-ideological mass shootings that have occurred around the world. It then examines the relationship between media consumption and perceptions of mass shootings. To this end, newspaper coverage on a sample of ten mass shootings from 2011-2021 are examined temporally using the Social Coping Model. Results show that media coverage varies across time …

Integrating Cultivar Resistance And Entomopathogens For Pest Management Of Sweetpotato Weevil, Cylas Formicarius Elegantulus (Summers), Schyler M. Lee

LSU Master's Theses

Sweetpotato, Ipomoea batatas (L.) Lam, is the number one vegetable crop in Louisiana, producing 21,178 kg/ha in the year 2021. The sweetpotato weevil, Cylas formicarius elegantulus (Summers), is an economically important pest of sweetpotato. C. formicarius elegantulus females lay eggs into feeding holes on the storage root surface. Larvae then hatch and tunnel through the sweetpotato flesh where they complete their development. This cryptic-natured brentid can cause up to 100% yield loss when left unmanaged. The Louisiana Department of Agriculture and Forestry mandates protocols to limit C. formicarius elegantulus spread (e.g., clean seed, pheromone trapping, and quarantines); however, scheduled chemical …

The Ọkụmkpọ Masquerades Of The Afikpo Society Of Southeastern Nigeria: An Art Form And An Instrument Of Social Control., Chinenye Miriam Emelogu

LSU Master's Theses

Masquerade performances are prevalent in West Africa, but they hold particular importance among the Igbo of Southeastern Nigeria. This thesis explores the cultural significance and artistic expressions of Okunkpo masquerade at Afikpo, a sub-Igbo group in Nigeria. It demonstrates how Okunkpo has served as a mechanism of social control using humorous skits, storytelling and dance up to the 21^st century. Okunkpo is an elaborate and the most attended masquerade performance at Afikpo. It appears only once in a year and is exclusively reserved for male initiates. Its popularity draws audience from far and near. As a community theatre, Okunkpo …

Regulation Of Nucleotide Excision Repair, Wenzhi Gong

LSU Doctoral Dissertations

Nucleotide excision repair (NER), a “cut and patch” mechanism, has two subpathways, namely transcription coupled repair (TCR) and global genome repair (GGR). TCR rapidly removes UV photoproduct (UV PP) in the transcribed strand (TS) of an actively transcribed gene, whereas GGR removes those DNA lesions throughout the genome. This dissertation mainly focused on identifying novel factors that function in NER and investigating the potential molecular mechanisms underlying initial damage recognition and downstream processes in NER. We identified Rpb7, a subunit of RNA polymerase II, represses TCR via its multiple regions. Specifically, the conserved region of Rpb7 that interacts with the …

Expressing Outrage, Re-Inventing Hope: Performing Nationhood In Nigerian Standup Comedy., Babasinmisola Fadirepo

LSU Doctoral Dissertations

The intersection of the Nigerian national identity and popular culture has been overwhelmingly located in the Nigerian movie industry and the Afrobeats, the flourishing Nigerian popular music. Further, when intervention about the Nigerian national identity is located within standup comedy performances, such analysis is vastly linguistic analysis of the performance. Through the lens of performance studies, this dissertation extends the discussion of the Nigerian national identity to standup comedy performances. In addition to the linguistic analysis of select Nigerian standup comedy performances, this work considers the location, costumes of comic acts, and the settings of the performance studied. Simply, this …

With Every Name But Yours: A New Orchestration Of Clémence De Grandval's Stabat Mater, David Walters

LSU Doctoral Dissertations

Clémence de Grandval was a late-Romantic composer whose extensive body of work, high profile performances, and numerous accolades should have garnered prominent placement among her contemporaries. Yet her vast collection of orchestral, choral, operatic, and other stage works have been all but forgotten.

Grandval’s Stabat Mater counted among her most popular works. Though the extant score for choir, harmonium (or organ), and piano explicitly references orchestral accompaniment1 , none of the parts or full score are available. Rather than providing a conductor’s guide or chord-by-chord analysis of Grandval’s work, this document breathes new life into this lost masterpiece by orchestrating …

Evidence For Two Soybean Looper Strains In The United States With Limited Capacity For Cross-Hybridization, Rodney N. Nagoshi, Jeffrey A. Davis, Robert L. Meagher, Fred R. Musser, Graham P. Head, Hector Portillo, Henry Teran

Faculty Publications

The noctuid moth soybean looper (SBL), Chrysodeixis includens (Walker) is an economically important pest of soybeans (Glycine max (L.) Merr.) in the southeastern United States. It has characteristics that are of particular concern for pest mitigation that include a broad host range, the capacity for annual long-distance flight, and resistance in some populations to important pesticides such as pyrethroids and chitin synthesis inhibitor. The biology of SBL in the United States resembles that of the fellow noctuid fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), a major pest of corn and several other crops. FAW exhibits a population structure in that …

Investigating The Migratory Behavior Of Soybean Looper, A Major Pest Of Soybean, Through Comparisons With The Corn Pest Fall Armyworm Using Mitochondrial Haplotypes And A Sex-Linked Marker, Rodney N. Nagoshi, Jeffrey A. Davis, Robert L. Meagher, Fred R. Musser, Graham P. Head, Hector Portillo, Henry Teran

Faculty Publications

The Noctuid moth soybean looper (SBL), Chrysodeixis includens (Walker), is an economically important pest of soybean (Glycine max (Linnaeus) Merrill). Because it is not known to survive freezing winters, permanent populations in the United States are believed to be limited to the southern regions of Texas and Florida, yet its geographical range of infestations annually extend to Canada. This indicates annual migrations of thousands of kilometers during the spring and summer growing season. This behavior is like that of the fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), also a Noctuid that is a major global pest of corn. SBL and …

Louisiana Agriculture Magazine, Summer 2023

Louisiana Agriculture

Rice, alligators and sugarcane are quintessential Louisiana products, and LSU AgCenter researchers and extension agents devote themselves to helping the producers who grow them. Economists are finding ways to improve the market for alligators while specialists focus on innovation in the sugar industry and creating new varieties of rice.

AgCenter researchers also have an eye on the natural world. They are protecting the roseau cane that thrives on the coast and the ironwood trees of Guam. All these efforts are detailed in this issue of Louisiana Agriculture magazine.

Extended Sentinel Monitoring Of Helicoverpa Zea Resistance To Cry And Vip3aa Toxins In Bt Sweet Corn: Assessing Changes In Phenotypic And Allele Frequencies Of Resistance, Galen P. Dively, Tom P. Kuhar, Sally V. Taylor, Helene Doughty, Kristian Holmstrom, Daniel O. Gilrein, Brian A. Nault, Joseph Ingerson-Mahar, Anders Huseth, Dominic Reisig, Shelby Fleischer, David Owens, Kelley Tilmon, Francis Reay-Jones, Pat Porter, Jocelyn Smith, Julien Saguez, Jason Wells, Caitlin Congdon, Holly Byker, Bryan Jensen, Chris Difonzo, William D. Hutchison, Eric Burkness, Robert Wright, Michael Crossley, Heather Darby, Tom Bilbo, Nicholas Seiter, Christian Krupke, Craig Abel, Brad S. Coates, Bradley Mcmanus

Faculty Publications

Transgenic corn and cotton that produce Cry and Vip3Aa toxins derived from Bacillus thuringiensis (Bt) are widely planted in the United States to control lepidopteran pests. The sustainability of these Bt crops is threatened because the corn earworm/bollworm, Helicoverpa zea (Boddie), is evolving a resistance to these toxins. Using Bt sweet corn as a sentinel plant to monitor the evolution of resistance, collaborators established 146 trials in twenty-five states and five Canadian provinces during 2020–2022. The study evaluated overall changes in the phenotypic frequency of resistance (the ratio of larval densities in Bt ears relative to densities in non-Bt ears) …

Substantially Enhanced Landscape Carbon Sink Due To Reduced Terrestrial-Aquatic Carbon Transfer Through Soil Conservation In The Chinese Loess Plateau, Lishan Ran, Nufang Fang, Xuhui Wang, Shilong Piao, Chun Ngai Chan, Siliang Li, Yi Zeng, Zhihua Shi, Mingyang Tian, Yi Jun Xu, Junyu Qi, Boyi Liu

Faculty Publications

Soil conservation is of global importance, as accelerated soil erosion by human activity is a primary threat to ecosystem viability. However, the significance and role of soil conservation in reshaping landscape carbon (C) accounting has not been comprehensively integrated in the terrestrial C sink. Here, we present the first integrated assessment of the modified terrestrial C sink and aquatic C transport due to soil conservation for the semiarid Chinese Loess Plateau (CLP), the world's most vulnerable region to soil erosion. We show a surprisingly low terrestrial-aquatic C transfer that offset the terrestrial net ecosystem productivity by only 7.5%, which we …

Long-Term Capture Data Uncover Shifts In The Daily Activity Patterns Of Amazonian Birds, Cameron L. Rutt, Philip C. Stouffer, Bruna R. Amaral, David A. Luther

Faculty Publications

Although the duration of biological rhythms varies from milliseconds to decades, daily cycles are especially widespread for individual organisms. These circadian rhythms are synchronized by light–dark cycles, which govern predictable changes in other microclimate variables. Despite the fixed, regular nature of these abiotic cycles at low latitudes, little is known about how different animals structure activity along these gradients. We used 25 years of capture–recapture data and ~ 25 000 unique captures to characterize ‘activity' (time of capture) for 65 species of Amazonian birds in the lowest forest stratum (0–2.5 m). To quantify vertical niche breadths, we also measured foraging …

Extensive Independent Amplification Of Platy-1 Retroposons In Tamarins, Genus Saguinus, Jessica M. Storer, Jerilyn A. Walker, Thomas O. Beckstrom, Mark A. Batzer

Faculty Publications

Platy-1 retroposons are short interspersed elements (SINEs) unique to platyrrhine primates. Discovered in the common marmoset (Callithrix jacchus) genome in 2016, these 100 bp mobile element insertions (MEIs) appeared to be novel drivers of platyrrhine evolution, with over 2200 full-length members across 62 different subfamilies, and strong evidence of ongoing proliferation in C. jacchus. Subsequent characterization of Platy-1 elements in Aotus, Saimiri and Cebus genera, suggested that the widespread mobilization detected in marmoset (family Callithrichidae) was perhaps an anomaly. Two additional Callithrichidae genomes are now available, a scaffold level genome assembly for Saguinus imperator (tamarin; SagImp_v1) and a chromosome-level assembly …

Medical Libraries And Their Complicated Past: An Exploration Of The Historical Connections Between Medical Collections And Racial Science, Raymond Pun, Patrice R. Green, Nicollette Davis

Faculty Publications

For over a millennium, libraries and library workers have advanced the knowledge of human science by building, preserving, and sharing collections and research. Historically, libraries have also aligned their institutional responsibilities to adhere to and support the values and virtues of oppressive and colonial practices. Library history has shown the mistreatments and denials of information access of marginalized groups. The history of libraries in the health and medical sciences reveals how these institutions and their workers have preserved and circulated research studies perpetuating racial science. This commentary highlights how such institutions shape and contribute to racial science in the field …

Simulation Of Radioactive Plume Transport In The Atmosphere Including Dynamics Of Particle Aggregation And Breakup, Alexander I. Wiechert, Austin P. Ladshaw, Yong Ha Kim, Costas Tsouris, Sotira Yiacoumi

Faculty Publications

Accurate prediction of the atmospheric transport of debris particles relies heavily on our knowledge of the size distribution of the particles within a debris cloud. Assuming a fixed particle size during simulations is not always viable since the size distribution of the debris can change during transport. Various microphysical processes, such as aggregation and breakup, influence debris particles and dictate any changes to the size distribution. To track those changes that can occur, a population balance model can be adopted and instituted within a model framework. Nonetheless, many of the models that simulate the transport of radioactive debris following a …

Transcription Factor Pecs Mediates Agrobacterium Fabrum Fitness And Survival, George C. Nwokocha, Prava Adhikari, Asif Iqbal, Hannah Elkholy, William T. Doerrler, John C. Larkin, Anne Grove

Faculty Publications

The transcriptional regulator PecS is encoded by select bacterial pathogens. For instance, in the plant pathogen Dickeya dadantii, PecS controls a range of virulence genes, including pectinase genes and the divergently oriented gene pecM, which encodes an efflux pump through which the antioxidant indigoidine is exported. In the plant pathogen Agrobacterium fabrum (formerly named Agrobacterium tumefaciens), the pecS-pecM locus is conserved. Using a strain of A. fabrum in which pecS has been disrupted, we show here that PecS controls a range of phenotypes that are associated with bacterial fitness. PecS represses flagellar motility and chemotaxis, which are processes that are …

Measuring Resilience To Sea-Level Rise For Critical Infrastructure Systems: Leveraging Leading Indicators, Lamis Amer, Murat Erkoc, Rusty A. Feagin, Sabarethinam Kameshwar, Katharine J. Mach, Diana Mitsova

Faculty Publications

There has been a growing interest in research on how to define and build indicators of resilience to address challenges associated with sea-level rise. Most of the proposed methods rely on lagging indicators constructed based on the historical performance of an infrastructure sub-system. These indicators are traditionally utilized to build curves that describe the past response of the sub-system to stressors; these curves are then used to predict the future resilience of the sub-system to hypothesized events. However, there is now a growing concern that this approach cannot provide the best insights for adaptive decision-making across the broader context of …

Impact Of Sediment Diversion For Coastal Restoration On Nitrogen And Phosphorus Biogeochemical Cycling In Coastal Louisiana, Usa, Mercedes M. Pinzon Delgado

LSU Master's Theses

Wetlands provide essential ecosystem services and functions, including improving surface water quality through nutrient removal. Louisiana experienced ~4,800 km² of coastal wetland loss between 1932 and 2016 due to high relative sea level rise and reduced sediment input from the Mississippi River (MR). The 2023 Louisiana Coastal Master Plan aims to restore Louisiana's degraded coastline through restoration projects, including sediment diversions. The Mid-Barataria Sediment Diversion project will reconnect MR sediment-laden water with Barataria Basin degrading marshes. The diversion will also deliver nitrate (NO₃^-) and soluble reactive phosphorus (SRP) to this basin, potentially negatively impacting water quality. …

Phenotypic And Genotypic Characterization Of Grain Quality In Rice And Implications For Breeding, Raul A. Guerra-Lacayo

LSU Doctoral Dissertations

Rice will continue to be a staple food for the foreseeable future, and plant breeding can foment the resilience of this crop. Applied breeding programs with clear objectives can effectively develop varieties that satisfy stakeholder needs. The majority of U.S.-produced rice is destined to export markets, and Latin America is the largest importer of U.S. rice, receiving 59% of total exports in 2021. Since 2010, Latin American importers voiced concerns about the quality of U.S. rice, mainly the high chalk content of milled rice and the stickiness of cooked rice. To address these issues, the objectives of this project were: …

Characteristics Of Yogurt And Culture Bacteria As Affected By Ingredients That Help Treat Leaky Gut, Ricardo Jose Santos Aleman

LSU Doctoral Dissertations

At least 100 million people have leaky gut syndrome. This syndrome is associated with multiple health problems such as diabetes, celiac disease, asthma, multiple sclerosis, and inflammatory bowel disease, costing more than $3 billion per year to treat. L-Glutamine, quercetin, slippery elm bark, marshmallow root, N-acetyl-d-glucosamine (NAG), licorice root, maitake mushrooms, and zinc orotate have been reported to help treat leaky gut.

The objectives were to explore the characteristics of yogurt and culture bacteria as affected by ingredients that help treat leaky gut. In yogurt, the pH, titratable acidity, syneresis, viscosity, color, Streptococcus thermophilus, Lactobacillus bulgaricus, yeast and mold and …

Rethinking Attention Control: An Individual Differences Approach, Vincent A. Medina

LSU Doctoral Dissertations

While there is extensive literature on visual spatial attention, less is known about auditory spatial attention, especially in terms of attention control. There is also a growing literature highlighting the importance of considering individual differences in attention control ability. Given these points, the purpose of this study was twofold. The first was to understand how auditory attention control is influenced by spatial location as well as vision. The second was to examine whether individual differences in attention control ability can predict task performance in that context. We utilized two tasks for these purposes. Experiment 1a consisted of a cross-modal Stroop …

Tracing Energy Pathways Through Coastal Wetland Food Webs, Katherine Loesser

LSU Master's Theses

Southeastern Louisiana’s coastal wetlands are important habitat for aquatic species, yet the spatial heterogeneity in habitat types and abundance of many basal energy sources makes it challenging to elucidate patterns of energy flow across the landscape mosaic. This ecosystem is experiencing substantial changes, both through anthropogenically-accelerated climate change and anthropogenic landscape modifications. Therefore, the overall goal of this thesis was to trace patterns of energy flow across coastal wetland landscapes to determine which basal energy pathways support aquatic food webs and if patterns of energy pathway dependence are altered by changes to the landscape. In the first part of this …