Digital Commons Network^™

Casting A Critical Lens On Global Development: A Multimethod Investigation Of The Masculine Hegemonic Forces That Marginalize Women In Agriculture, Morgan Alyse Richardson Gilley

LSU Doctoral Dissertations

A critical link between gender equality and agricultural development has been established in the literature. However, disparities between genders have persisted in many areas of the developing world. One strategy that has been used to reduce gender inequalities has been educational outreach opportunities through agricultural extension, which has provided women a critical pathway to empowerment. Despite this, a lack of knowledge on the experiences of women in agriculture throughout Southeast Asia has served as a barrier to the advancement of such work. This investigation sought to better understand the issues facing this region’s fight to attain gender equality. To achieve …

The Confederate Stories Of America: The Short-Story Cycle And The Representation Of The American South, Ikuko Takeda

LSU Doctoral Dissertations

My dissertation examines the ways in which the short-story cycle has provided a unique generic framework for representing and investigating the complex interplay of contending forces that constitute what we think of as the American South. Often confused with a collection of disparate short stories or a novel, the short-story cycle is a collection of short stories in which each story is independent, but simultaneously interrelated to one another. Although the South has produced a number of short-story cycles or linked story collections, scholars have not paid much attention to the connection between the genre/form and the region. I consider, …

Fatigue Damage Quantification And Life Estimation With Provision For Microstructure, Arash Pourbagheri Jirandehi

LSU Doctoral Dissertations

This dissertation provides methodologies for the quantification of different forms of fatigue damage by considering the role of microstructure. The laws of thermodynamics in conjunction with Finite Element Method (FEM) are utilized to devise thermodynamically-base frameworks for the estimation of cyclic damage in polycrystalline metals. Accordingly, a microstructure-sensitive platform for fatigue life estimation is introduced. The proposed framework is assessed for 3D printed metallic alloys at room and elevated temperatures. Further, it is used to analyze the fatigue performance difference between additively manufactured Inconel 718 in three print orientations. This research is of fundamental vital interest because it ensures that …

Ontogeny And Resource Use Of Invasive Lionfish, Pterois Volitans, In Shallow Water Habitats Surrounding Summerland Key, Emily Shallow

LSU Master's Theses

The invasive red lionfish, Pterois volitans, has been shown to considerably reduce reef biomass via predation and competition in non-native ranges. Primary maintenance of lionfish is through human removal (e.g., culling), which does not sufficiently control the population due to deep-water spawning, recolonization of recently culled reefs, and ontogenetic migrations to mesophotic waters. Here, I investigated the diets and primary energy pathways during ontogeny in lionfish from the Florida Keys using stomach contents and stable isotope (δ¹³C and δ¹⁵N) analysis to better understand their role in the trophic food web. Additionally, isotopic overlap between lionfish …

Tau-Atrophy Variability Reveals Phenotypic Heterogeneity In Alzheimer's Disease, Sandhitsu R. Das, Xueying Lyu, Michael Tran Duong, Long Xie, Lauren Mccollum, Robin De Flores, Michael Dicalogero, David J. Irwin, Bradford C. Dickerson, Ilya M. Nasrallah, Paul A. Yushkevich, David A. Wolk, Michael Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, Andrew J. Saykin, John Morris, Leslie M. Shaw, Enchi Liu, Tom Montine, Ronald G. Thomas, Michael Donohue, Michael Donohue, Sarah Walter, Devon Gessert, Tamie Sather, Gus Jiminez, Danielle Harvey

Clinical Research Faculty Publications

Objective: Tau neurofibrillary tangles (T) are the primary driver of downstream neurodegeneration (N) and subsequent cognitive impairment in Alzheimer's disease (AD). However, there is substantial variability in the T-N relationship – manifested in higher or lower atrophy than expected for level of tau in a given brain region. The goal of this study was to determine if region-based quantitation of this variability allows for identification of underlying modulatory factors, including polypathology. Methods: Cortical thickness (N) and 18F-Flortaucipir SUVR (T) were computed in 104 gray matter regions from a cohort of cognitively-impaired, amyloid-positive (A+) individuals. Region-specific residuals from a robust linear …

Real Space Quantum Cluster Formulation For The Typical Medium Theory Of Anderson Localization, Ka Ming Tam, Hanna Terletska, Tom Berlijn, Liviu Chioncel, Juana Moreno

Faculty Publications

We develop a real space cluster extension of the typical medium theory (cluster-TMT) to study Anderson localization. By construction, the cluster-TMT approach is formally equivalent to the real space cluster extension of the dynamical mean field theory. Applying the developed method to the 3D Anderson model with a box disorder distribution, we demonstrate that cluster-TMT successfully captures the localization phenomena in all disorder regimes. As a function of the cluster size, our method obtains the correct critical disorder strength for the Anderson localization in 3D, and systematically recovers the re-entrance behavior of the mobility edge. From a general perspective, our …

Jasmonic Acid-Induced Resistance To Fall Armyworm In Soybeans: Variation Among Genotypes And Tradeoffs With Constitutive Resistance, Srinivas K. Lanka, Bret D. Elderd, Jeffrey A. Davis, Michael J. Stout

Faculty Publications

A negative correlation between constitutive and inducible resistance across plant populations is expected for a variety of reasons; however, empirical evidence for such trade-offs remain ambiguous, particularly for crop plants. The current study investigated the relationship between constitutive and inducible resistance in vegetative-stage soybeans (V5-V6) against larvae of the generalist defoliator, Spodoptera frugiperda. Eighteen soybean genotypes differing in their constitutive resistance to coleopteran or lepidopteran defoliators were used over four experiments. Exogenous jasmonic acid (JA, 2 mM) was used to induce plants. Constitutive resistance of each genotype was estimated by measuring weight gains, foliar consumption, and foliar conversion efficiency in …

Use Of Racial And Ethnic Categories In Medical Testing And Diagnosis: Primum Non Nocere, Jay S. Kaufman, Joanna Merckx, Richard S. Cooper

Faculty Publications

BACKGROUND: Use of race and ethnicity is common in medical tests and procedures, even though these categories are defined by sociological, historical, and political processes, and vary considerably in their definitions over time and place. Because all societies organize themselves around these constructs in some way, they are undeniable facets of the human experience, with myriad health consequences. In the biomedical literature, they are also commonly interpreted as representing biological heterogeneity that is relevant for health and disease. CONTENT: We review the use of race and ethnicity in medical practice, especially in the USA, and provide 2 specific examples to …

Resistance To Aflatoxin Accumulation In Maize Mediated By Host-Induced Silencing Of The Aspergillus Flavus Alkaline Protease (Alk) Gene, Olanike Omolehin, Yenjit Raruang, Dongfang Hu, Zhu Qiang Han, Qijian Wei, Kan Wang, Kanniah Rajasekaran, Jeffrey W. Cary, Zhi Yuan Chen

Faculty Publications

Aspergillus flavus is a fungal pathogen that infects maize and produces aflatoxins. Host-Induced Gene Silencing (HIGS) has been shown to reduce host infection by various fungal pathogens. Here, the A. flavus alkaline protease (alk) gene was targeted for silencing through HIGS. An RNAi vector carrying a portion of the alk gene was incorporated into the B104 maize genome. Four out of eight transformation events containing the alk gene, Alk-3, Alk-4, Alk-7 and Alk-9, were self-pollinated to T4/T6 generations. At T3, the Alk-transgenic lines showed up to 87% reduction in aflatoxin accumulation under laboratory conditions. T4 transgenic Alk-3 and Alk-7 lines, …

Word-Learning Trajectories Influence Long-Term Recall In Children With Developmental Language Disorder And Typical Development, Justin B. Kueser, Laurence B. Leonard, Patricia Deevy, Eileen Haebig, Jeffrey D. Karpicke

Faculty Publications

Introduction: Children with developmental language disorder (DLD) have difficulties learning words. However, the severity of these difficulties can be reduced through word learning procedures that incorporate repeated spaced retrieval (RSR). Previous studies have shown positive outcomes with RSR but we still know very little about how learning unfolds with this procedure. In this study, we focus on the process of learning under RSR. Methods: We analyze the learning data from children with DLD and with typical development (TD) from three recent studies using RSR. We fit growth curves to the trial-by-trial learning data for immediate and spaced retrieval trials and …

Effects Of Testosterone Administration On Fmri Responses To Executive Function, Aggressive Behavior, And Emotion Processing Tasks During Severe Exercise- And Diet-Induced Energy Deficit, Owen T. Carmichael, Sreekrishna R. Pillai, Kori Murray, Preetham Shankapal, John Caldwell, Oshin Vartanian, Claire E. Berryman, J. P. Karl, Melissa Harris, Jennifer C. Rood, Stefan M. Pasiakos, Harris R. Lieberman

Clinical Research Faculty Publications

Background: Clinical administration of testosterone is widely used due to a variety of claimed physical and cognitive benefits. Testosterone administration is associated with enhanced brain and cognitive function, as well as mood, in energy-balanced males, although such relationships are controversial. However, the effects of testosterone administration on the brains of energy-deficient males, whose testosterone concentrations are likely to be well below normal, have not been investigated. Methods: This study collected functional magnetic resonance imaging (fMRI) data from 50 non-obese young men before (PRE) and shortly after (POST) 28 days of severe exercise-and-diet-induced energy deficit during which testosterone (200 mg testosterone …

And The Heat Goes On: Police Repression And The Modalities Of Power, Howard Liu, Christopher M. Sullivan

Faculty Publications

Among security institutions, police occupy a unique position. In addition to specializing in the repression of dissent, police monitor society and enforce order. Yet within research studying state repression, how police institutions are used and deployed to control domestic threats remain under-explored, particularly as it relates to the dual functionality just described. In this study, we develop and test an explanation of police repression accounting for the bifurcation of Mann’s two modalities of state power: infrastructural power and despotic power. Infrastructural power allocates police resources to surveil dissidents and preemptively limit dissent’s emergence or escalation. Police deploy despotic power through …

The Path Of Least Resistance?: Women Government Attorneys’ Success At The U.S. Supreme Court, Bailey Chauvin

Honors Capstones

No abstract provided.

Shape-Based Classification Of Partially Observed Curves, With Applications To Anthropology, Gregory J. Matthews, Karthik Bharath, Sebastian Kurtek, Juliet K. Brophy, George K. Thiruvathukal, Ofer Harel

Faculty Publications

We consider the problem of classifying curves when they are observed only partially on their parameter domains. We propose computational methods for (i) completion of partially observed curves; (ii) assessment of completion variability through a nonparametric multiple imputation procedure; (iii) development of nearest neighbor classifiers compatible with the completion techniques. Our contributions are founded on exploiting the geometric notion of shape of a curve, defined as those aspects of a curve that remain unchanged under translations, rotations and reparameterizations. Explicit incorporation of shape information into the computational methods plays the dual role of limiting the set of all possible completions …

The Young Black Girl: A Narration Of Stem Identity Through Science Origin In Elementary School, Heather F. Lavender

LSU Doctoral Dissertations

An ethnographic qualitative case study was conducted by examining the perceptions of two 5^th grade Black girls at an independent school about their involvement with school science, the impact of race and gender towards their perception, and the influence of teachers, peers, and family on their science identity. Black girls are often relegated to outsider status within the classroom, lacking power and authority, which results in Black girls being denied a rightful presence in their learning community (Dumas & Ross, 2016). Additionally, their presence in STEM careers does not reflect their presence nationwide (Graves et al., 2014). The proposed …

Recursive And Viterbi Estimation For Semi-Markov Chains, Robert J. Elliott, W. P. Malcolm

Journal of Stochastic Analysis

No abstract provided.

On The Mathematical Modeling Of Slender Biomedical Continuum Robots, Hunter B. Gilbert

Faculty Publications

The passive, mechanical adaptation of slender, deformable robots to their environment, whether the robot be made of hard materials or soft ones, makes them desirable as tools for medical procedures. Their reduced physical compliance can provide a form of embodied intelligence that allows the natural dynamics of interaction between the robot and its environment to guide the evolution of the combined robot-environment system. To design these systems, the problems of analysis, design optimization, control, and motion planning remain of great importance because, in general, the advantages afforded by increased mechanical compliance must be balanced against penalties such as slower dynamics, …

Rough Paths And Regularization, André O. Gomes, Alberto Ohashi, Francesco Russo, Alan Teixeira

Journal of Stochastic Analysis

No abstract provided.

Louisiana Agriculture Fall, 2021, Lsu Agcenter

Louisiana Agriculture

No abstract provided.

F21rs Sgb No. 3 (Constitutional Amendment), Taylor Perrodin, Matthew Mcclure, Colin Raby, Harris Quadir, Miles Mclendon

Student Senate Enrolled Legislation

A Bill

To amend the Constitution of the Student Government of Louisiana State University

Assessment Of Silicon-And Mycorrhizae-Mediated Constitutive And Induced Systemic Resistance In Rice, Oryza Sativa L., Against The Fall Armyworm, Spodoptera Frugiperda Smith, Santhi Bhavanam, Michael J. Stout

Faculty Publications

Induced resistance provides protection in plants against insect herbivores. Silicon and mycorrhizae often prime plant defenses and thereby enhance plant resistance against herbivores. In rice, Oryza sativa L., insect injury has been shown to induce resistance against future defoliators. However, it is unknown if silicon and mycorrhizae treatments in combination with insect injury result in greater induced resistance. Using the fall armyworm (FAW), Spodoptera frugiperda Smith, two experiments were conducted to investigate whether (1) silicon or mycorrhizae treatment alters resistance in rice and (2) induced systemic resistance in response to insect injury is augmented in silicon-or mycorrhizae-treated plants. In the …

Fall 2021 Catalog, Lsu Press

LSU Press Seasonal Catalogs

No abstract provided.

Genetic Knockouts Indicate That The Abcc2 Protein In The Bollworm Helicoverpa Zea Is Not A Major Receptor For The Cry1ac Insecticidal Protein, Omaththage P. Perera, Nathan S. Little, Heba Abdelgaffar, Juan Luis Jurat-Fuentes, Gadi V.P. Reddy

Faculty Publications

Members of the insect ATP binding cassette transporter subfamily C2 (ABCC2) in several moth species are known as receptors for the Cry1Ac insecticidal protein from Bacillus thuringiensis (Bt). Mutations that abolish the functional domains of ABCC2 are known to cause resistance to Cry1Ac, although the reported levels of resistance vary widely depending on insect species. In this study, the function of the ABCC2 gene as a putative Cry1Ac receptor in Helicoverpa zea, a major pest of over 300 crops, was evaluated using CRISPR/Cas9 to progressively eliminate different functional ABCC2 domains. Results from bioassays with edited insect lines support that mutations …

Effect Of Aerobic Exercise-Induced Weight Loss On The Components Of Daily Energy Expenditure, Nicholas T. Broskey, Corby K. Martin, Jeffrey H. Burton, Timothy S. Church, Eric Ravussin, Leanne M. Redman

Clinical Research Faculty Publications

Introduction Exercise usually results in less weight loss than expected. This suggests increased energy intake and/or deceased expenditure counteract the energy deficit induced by exercise. The aim of this study was to evaluate changes in components of daily energy expenditure (doubly labeled water and room calorimetry) after 24 wk of exercise training with two doses of aerobic exercise. Methods This was an ancillary study in 42 (29 women, 13 men) sedentary, middle-age (47.8 ± 12.5 yr) individuals with obesity (35 ± 3.7 kg·m-2) enrolled in the Examination of Mechanisms of Exercise-induced Weight Compensation study. Subjects were randomized to three groups: …

Analysis Of A New Multispecies Tumor Growth Model Coupling 3d Phase-Fields With A 1d Vascular Network, Marvin Fritz, Prashant K. Jha, Tobias Köppl, J. Tinsley Oden, Barbara Wohlmuth

Faculty Publications

In this work, we present and analyze a mathematical model for tumor growth incorporating ECM erosion, interstitial flow, and the effect of vascular flow and nutrient transport. The model is of phase-field or diffused-interface type in which multiple phases of cell species and other constituents are separated by smooth evolving interfaces. The model involves a mesoscale version of Darcy's law to capture the flow mechanism in the tissue matrix. Modeling flow and transport processes in the vasculature supplying the healthy and cancerous tissue, one-dimensional (1D) equations are considered. Since the models governing the transport and flow processes are defined together …

Modeling And Simulation Of Vascular Tumors Embedded In Evolving Capillary Networks, Marvin Fritz, Prashant K. Jha, Tobias Köppl, J. Tinsley Oden, Andreas Wagner, Barbara Wohlmuth

Faculty Publications

In this work, we present a coupled 3D–1D model of solid tumor growth within a dynamically changing vascular network to facilitate realistic simulations of angiogenesis. Additionally, the model includes erosion of the extracellular matrix, interstitial flow, and coupled flow in blood vessels and tissue. We employ continuum mixture theory with stochastic Cahn–Hilliard type phase-field models of tumor growth. The interstitial flow is governed by a mesoscale version of Darcy's law. The flow in the blood vessels is controlled by Poiseuille flow, and Starling's law is applied to model the mass transfer in and out of blood vessels. The evolution of …

Consensus Revisited: Quantifying Scientific Agreement On Climate Change And Climate Expertise Among Earth Scientists 10 Years Later, Krista F. Myers, Peter T. Doran, John Cook, John E. Kotcher, Teresa A. Myers

Faculty Publications

The scientific consensus on human-caused global warming has been a topic of intense interest in recent decades. This is in part due to the important role of public perception of expert consensus, which has downstream impacts on public opinion and support for mitigation policies. Numerous studies, using diverse methodologies and measures of climate expertise, have quantified the scientific consensus, finding between 90% and 100% agreement on human-caused global warming with multiple studies converging on 97% agreement. This study revisits the consensus among geoscientists ten years after an initial survey of experts, while exploring different ways to define expertise and the …

Calculating Pile Downdrag: Experimental And Numerical Investigations, Hai Lin, Shengli Chen, Hussein Alqrinawi

Publications

Piles can be exposed to significant settlement (i.e., downdrag) and compressive force (i.e., dragload) if embedded in consolidating ground. Downdrag has been included in the design of piles, but there is uncertainty about how downdrag and dragload are efficiently considered in the pile design due to the differences in the existing design methods (e.g., AASHTO and FHWA). Although several field monitoring programs were successfully conducted on pile downdrag, fully instrumented pile model tests are still needed to investigate the responses at the soil-pile interface to improve the design of pile downdrag. This research focused on investigating the downdrag and skin …

Urban Transportation Infrastructure And Cyclist And Pedestrian Safety, Hatim Sharif, Samer Dessouky

Publications

The goal of this project was to perform a comprehensive evaluation of crash causes and risk factors to identify the root causes of crashes involving bicyclists and pedestrians in San Antonio, TX. The research included the development of a database of bicycle and pedestrian crash reports in the target area, calculation of crash counts and rates, identifying road segments and intersections with highly concentrated bicycle and pedestrian crashes, and the development of effective safety countermeasures. Several variables and factors were analyzed, including driver characteristics such as age and gender, road-related factors, and environmental factors such as weather conditions and time …

An Examination Of Yoga To Improve Symptoms Of Post-Traumatic Stress In Firefighters, Amanda Joy Weathers-Meyer

LSU Doctoral Dissertations

Firefighters routinely experience traumatic events while executing their daily occupational duties; in turn, this elevates their risk of experiencing post-traumatic stress symptomatology (PTSS). To successfully contend with repeated trauma exposure, effective and culturally appropriate treatment options for firefighters are needed. A growing body of literature shows that yoga effectively reduces PTSS, notably with those in male-dominated fields. Despite these encouraging findings, the impact of yoga on PTSS among fire service personnel has yet to be examined. Therefore, this dissertation aimed to: (a) obtain preliminary data on yoga’s effectiveness to reduce PTSS in firefighters, (b) investigate cultural appropriateness and firefighter receptivity …