Digital Commons Network^™

Comprehensive Investigation Of Radiation Techniques For Whole Breast And Post-Mastectomy Irradiations, Yibo Xie

LSU Doctoral Dissertations

Purpose: The purpose of this dissertation is to compare treatment outcomes and cost-effectiveness of various radiotherapy techniques for post-mastectomy radiotherapy (PMRT) and whole breast radiotherapy (WBRT) patients.

Methods: Treatment planning comparison of standard volumetric modulated arc therapy (STD-VMAT), multiple arc VMAT (MA-VMAT), non-coplanar VMAT (NC-VMAT), intensity modulated radiotherapy (IMRT), helical tomotherapy (HT), mixed beam therapy and proton therapy was performed for 9 PMRT patients, and cost-effectiveness of those PMRT techniques compared to standard of care (SOC) were evaluated using a Markov model. Treatment planning comparison of SOC, field-in-field (FIF), hybrid IMRT, full IMRT, STD-VMAT, MA-VMAT and NC-VMAT was performed …

Quantifying Brain Network Coordination During The Imaginal Replay Of Naturalistic Shared Experiences Through Role-Playing Games, Zachary Traylor

Honors Capstones

No abstract provided.

University Students' Perceptions Of Humor Use By Male And Female Language Teachers In Lower And Intermediate-Level Spanish Classes, Anne-Catherine Jagneaux

LSU Master's Theses

This study explores students’ perceptions of their teachers based upon the teacher’s use of humor. It was guided by the following two research questions: 1) What are students’ overall opinions of the use of humor in the classroom in terms of its effect on the perceived characteristics of teachers?, and 2) Do male and female students perceive humor differently based on the gender of the teacher? Data were obtained to investigate how students view their teachers’ characteristics such as credibility, approachability, intelligence, overall likeability, in relation to their use of humor. The question of gender bias was addressed by investigating …

Vegetation Prior To And During Onset Of East Antarctic Glaciation: High Resolution Palynological Insights From Sabrina Coast, East Antarctica, Meghan L. Duffy

LSU Master's Theses

The Aurora Subglacial Basin (ASB) contains an estimated 3.5 m of global sea-level equivalent ice volume and is primarily drained by the Totten Glacier system, which terminates at the Sabrina Coast, East Antarctica. Thinning and retreating of the Totten Glacier indicate that this region is highly susceptible to oceanographic and atmospheric warming. The paleoclimate reconstruction of these changes, conducted in the context of this MS thesis, will improve understanding of East Antarctic Ice Sheet (EAIS) dynamics in this sensitive system. A recent study used seismic and sediment core data to document a dynamic early evolution of the EAIS in the …

Dissipation Of Benzobicyclon And Benzobicyclon Hydrolysate In A Louisiana Rice Field, Xavier Poole

LSU Master's Theses

Pesticide resistance in rice fields is an ongoing issue that has resulted in the development and use of pesticides with new modes of action. Benzobicyclon is the first registered hydroxyphenylpyruvate(HPPD)-inhibiting pesticide in the United States and has gained attention as a resistance management strategy to control weed pests in rice fields. Understanding the environmental fate and dissipation mechanisms of benzobicyclon is important due to the unique rotation of rice and crayfish in Louisiana on the same fields. Benzobicyclon persistence into the crayfish growing seasons may lead to unintended consequences for crayfish growth and production, assuming there is toxicity to crawfish. …

Community Dynamics Of Fish Assemblages On Mid-Shelf And Outer-Shelf Coral Reefs In The Northwestern Gulf Of Mexico, Lynne S. Wetmore, Michael A. Dance, Ronald L. Hill, Jay R. Rooker

Faculty Publications

Offshore coral reefs in the Gulf of Mexico (GOM) are unique model systems for examining the mechanisms structuring reef fish communities due to their substantial geographic isolation, and the presence of replicate experimental units of both low (mid-shelf) and high coral diversity (shelf-edge) reefs. Here, we examined the species assemblage structure of juvenile and adult fishes at two mid-shelf reefs (Sonnier and Stetson Bank) and two shelf-edge reefs (East and West Flower Garden Banks) in the northwestern GOM to evaluate the relative importance of habitat (i.e., coral diversity) vs. recruitment in structuring resident fish assemblages. Visual reef fish surveys (n …

Summertime: A Mixed-Methodolody Study Exploring The Effects Of A University Career And Professional Development Course As First-Year Student-Athletes Transition Into The University, Lori Simone' Robinson

LSU Doctoral Dissertations

The purpose of this study was to understand what, if any effect, an intervention such as a summer bridge program or course designed for incoming student-athletes had on the participants. Specifically, this study used Gaston-Gales (2004) Student-Athlete Motivation towards Sport and Academics Questionnaire (SAMSAQ) as a pre and post-intervention measure that examined the effect of the Student-Athlete Development Course 101 (SADC 101), which was designed and implemented mainly by athletics department personnel. The three constructs that the SAMSAQ instrument examined were: 1) Academic Motivation (AM), 2.) Student-Athlete Motivation (SAM), and 3.) Career-Athletic Motivation (CAM). The sample population (N=60) included only …

Genomics And Population History Of Black-Headed Bulbul (Brachypodius Atriceps) Color Morphs, Subir B. Shakya

LSU Doctoral Dissertations

Intraspecific polymorphism in birds, especially color polymorphism, is an area of active research in evolutionary biology. In this dissertation, I applied WGS to uncover the potential genetic underpinnings of color polymorphism in the Black-headed Bulbul (Brachypodius atriceps) of Southeast Asia. This species was selected because of the heterogeneous dispersion of two morphs across its range: a yellow form predominating on mainland Asia and the Greater Sunda Islands and a gray morph on two islands—Bawean and Maratua.

I approached this project from three angles. First, I reconstructed the phylogeny of the bulbul family, Pycnonotidae, to examine patterns of coloration …

"There Is Enough Food On The Table": Religious Minority Students' Experiences With The Campus Spiritual Climate, Regina C. Schneider

LSU Master's Theses

Within the last 30 years, diversity, equity, and inclusion initiatives have been at much of the forefront of student affairs and higher education policy and practices. Issues regarding gender, race, and socioeconomic status have received much attention not only in education, but also in the greater landscape of the nation. Religious and spiritual minority students are a population that has only recently been considered in fostering a more inclusive and pluralistic college environment. Thus, there is a research gap involving religious/spiritual minority college students and their perceptions of the campus climate. Additionally, only a small pool of research addresses the …

Investigation Of Tracer-Surfactant-Foam Processes In Shallow Subsurface Environmental Remediation: History-Matching And Performance Prediction, Hazem Fleifel

LSU Master's Theses

In-situ subsurface remediation has been widely used as an efficient means of cleaning up non-aqueous phase liquid (NAPL) from contaminated soils and aquifer. The use of tracer, surfactant, and foam are often considered to keep track of the propagation of injected fluids in the medium, dissolve and mobilize contaminants trapped by capillary forces, and overcome the level of heterogeneity and improve displacement and sweep efficiencies.

This study shows an actual remediation process to reduce NAPL within a military base in South Korea, by injecting tracer and surfactant solutions together for a duration of 10 days. The site consists of 5 …

Phytoplankton And Carbon Dynamics In The Estuarine-Coastal Waters Of The Northern Gulf Of Mexico From Field Data And Ocean Color Remote Sensing, Bingqing Liu

LSU Doctoral Dissertations

In this study, phytoplankton community and carbon dynamics were examined in the optically complex estuarine-coastal regions of the northern Gulf of Mexico (nGOM) from field and satellite ocean color observations. As part of this study, bio-optical ocean color algorithms for i) dissolved organic carbon (DOC), ii) phytoplankton pigment composition, iii) adaptive estimation of Chl a and iv) phytoplankton size fractions were developed to facilitate the study of biogeochemical cycling in the nGOM.

The phytoplankton based algorithms were applied to Sentinel 3A/B-OLCI oean color data to assess phytoplankton community dynamics to extreme river discharge conditions as well as hurricanes in the …

Examining Political Ambition: Competition And Leadership In Youth Activities, Ashley Staszak

LSU Master's Theses

Significant amounts of previous research focused on political ambition as a source of the gender gap in representation (Beyer and Bowden 1997; Pajares 2002; Fox 2010; Fox and Lawless 2014). This research looks to examine extracurricular activities (or after-school activities) and the effects they have on political ambition of girls as they grow up. Extracurricular activities provide girls access to competition, risk and female role models which can work to combat gender role socialization and other hindrances to running for political office. Using a survey of 300 undergraduate students at a large southern university, I measure the effect of extracurricular …

Acoustic Measures Of The Singing Voice In Secondary School Students, Elizabeth M. Wallace

LSU Doctoral Dissertations

Descriptions of voice quality in vocal and choral music often rely on subjective terminology, which may be perceived differently between individuals. As access to software used in acoustic measurement becomes more widespread and affordable, music educators can potentially combine traditional descriptive terminology with objective acoustic descriptors and data, which may improve both teaching and singing. The secondary school choral music educator has specific challenges, in that they teach students who experience drastic physical and acoustic changes of the voice as they grow from children to adults. The purpose of this study was to objectively analyze various acoustic characteristics of the …

Taxonomy And Systematics Of The New Zealand Pselaphini (Coleoptera: Staphylinidae: Pselaphinae), Brittany Elin Owens

LSU Doctoral Dissertations

The New Zealand (NZ) Pselaphini was revised at the species level, a phylogenetic analysis was performed using morphological data, and first steps were taken towards the construction of a molecular analysis of the tribe. Eight new genera and 33 new species were discovered from specimens collected from the NZ mainland, offshore islands, Chatham Islands and the Subantarctic Islands. Of the 13 species originally described in the genus Pselaphus by Thomas Broun during the late 19^th and early 20^th centuries, all were either reassigned to the genera Pselaphaulax and Pselaphogenius, or were placed into new genera. Three names …

Element Transport In A River-Lake Continuum Across Forest-Dominated Landscapes: A Case Study In Central Louisiana, Zhen Xu

LSU Doctoral Dissertations

Studying the biogeochemical connectivity between rivers and lakes can help us understand their ecological and environmental impacts within a drainage basin, which is especially true for forest watersheds that play a vital role in provisioning freshwater services to ecosystems and downstream communities. This dissertation research consists of three interconnected studies with the overarching goal of discerning the connectivity of elements in a river-lake continuum across forest-dominated landscapes. These studies utilized water samples and in situ measurements collected from the Little River-Catahoula Lake continuum in the subtropical Louisiana, USA at monthly intervals during 2015-2016 and 1978-2008 historical water quality, hydrological and …

Hydrodynamics And Sediment Dynamics In A Receiving Basin For Sediment Diversion: A Case Study In Barataria Bay, Louisiana, Usa, Guandong Li

LSU Master's Theses

Barataria Bay is a receiving basin of Mid-Barataria Sediment Diversion in Louisiana, USA. In this region the data of sediment transport and hydrodynamics are scarce but important for the design and planning of sediment diversion to be implemented in near future. Four-months bottom boundary layer observation was conducted to study winter and spring hydrodynamics and sediment dynamics in the bay. Hourly waves, tides, currents and bottom suspended sediment concentration were measured using multiple optical and acoustic sensors attached to two tripod platforms. High-temporal resolution data indicated that during winter, salinity at northern bay was mainly controlled by northerly wind during …

Investigating The Role Of Torc1 And The Transcription Factor Sfp1p In The Regulation Of Hmo1 Gene In Saccharomyces Cerevisiae, Mathew Damien Smith

LSU Master's Theses

HMGB proteins are eukaryotic, chromatin-associated proteins that play roles in both DNA dynamics and transcription regulation. Hmo1p is an HMGB protein in Saccharomyces cerevisiae that behaves somewhat like a hybrid between mammalian HMGB proteins and the metazoan linker histone H1. mTORC1, a protein complex containing the Tor1p kinase and a major regulator of cellular growth, is inhibited by both rapamycin and stress. It has also been shown to not only associate with Hmo1p at various gene promoters, but also regulate the HMO1 gene itself through direct binding. In this study, the Hmo1p-mTORC1 relationship was further investigated through two questions: 1) …

In Vitro Analysis Of Equine Platelet Rich Plasma And In Vivo Effect Of Cytokines After Repeated Intra-Articular Injections In Osteoarthritic Joints, Carlos Aguilar Miranda

LSU Master's Theses

INTRODUCTION- The use of biologic therapies like platelet rich plasma (PRP) has a potential benefit for the treatment of osteoarthritis in horses. However, key parts of it are still unknown. The objective is to evaluate the degree of platelet activation achieved when in contact with exogenous activators. As well as the long-term effect in the anabolism and catabolism of cytokines involved in equine osteoarthritis.

MATERIAL AND METHODS-In one in vitro study PRP was collected from 6-horses using a commercially available kit. Platelets were exposed to PBS as negative control or to varying concentrations of CaCl2. Activation was determined via cell …

Inhibiting Iron Mobilization From Bacterioferritin In Pseudomonas Aeruginosa Impairs Biofilm Formation Irrespective Of Environmental Iron Availability, Anabel Soldano, Huili Yao, Josephine R. Chandler, Mario Rivera

Faculty Publications

Copyright © 2020 American Chemical Society. Although iron is essential for bacteria, the nutrient presents problems of toxicity and solubility. Bacteria circumvent these problems with the aid of iron storage proteins where Fe3+ is deposited and, when necessary, mobilized as Fe2+ for metabolic requirements. In Pseudomonas aeruginosa, Fe3+ is compartmentalized in bacterioferritin (BfrB), and its mobilization as Fe2+ requires specific binding of a ferredoxin (Bfd) to reduce the stored Fe3+. Blocking the BfrB-Bfd complex leads to irreversible iron accumulation in BfrB and cytosolic iron deprivation. Consequently, given the intracellular iron sufficiency requirement for biofilm development, we hypothesized that blocking the …

Couples' Relationship Qualities And Child Behavior Problems, Erin Wallace Lovett

LSU Doctoral Dissertations

ABSTRACT

This dissertation examines couples’ relationship quality on child externalizing behavior problems. Family systems theory and Belsky’s determinants of parenting model posit that child behavior problems stem from problematic familial relationships and lack of support within the couple’s relationship. A secondary data analysis was conducted using data from the National Fragile Families and Child Wellbeing Study. The independent variables represent couples’ relationship quality and are affection/support, relationship instability, and coercion. Dependent variables represent child behavior problems and are aggression measured when children are age five and age nine, and rule-breaking behavior when the child is age nine. To examine what …

Memory-Modulated Cir Process With Discrete Delay Coefficients, Pathiranage Lochana Siriwardena, Harry Randolph Hughes, D. G. Wilathgamuwa

Journal of Stochastic Analysis

No abstract provided.

Functions Of Cdk/Cyclin Complexes In Endoreplication Regulation By The Cdk Inhibitor Siamese, Kai Wang

LSU Doctoral Dissertations

Arabidopsis trichome (leaf hair) is a specialized single cell extended from epidermal cell on the leaves, which is a typical endoreplication and is also known as endoreduplication. Several D-type cyclins were tested to check the cell division in trichome, and the trichome expressing either CYCB1;2 or CDKB2;2 cannot trigger cell division, even if simultaneous expression of CYCB1;2 and CDKB2;2 failed to produce mitosis in trichome. Only CYCD3;1 specifically promotes multicellular trichome. cdkb1;1cdbk1;2 double mutants and sim cdkb1;1cdkb1;2 triple mutants exhibit the phenotype similar to the wild type and very limited cell division respectively. Overexpression of a CDKB1;1 dominant-negative construct that …

Conservation Potential And Mechanisms Of Avian Decline In Experimentally Fragmented And Regenerating Amazonian Rainforest, Cameron Lee Rutt

LSU Doctoral Dissertations

Twenty percent of the Brazilian Amazon has now been deforested, and deforestation rates are increasing. Yet the process of deforestation threatens biodiversity beyond the direct loss of habitat by inducing edge effects and creating forest fragments. In the tropics, among the most vulnerable birds to these human disturbances are a group of insectivorous species that forage on or near the ground. A variety of mechanisms have been proposed to explain these declines, but evidence for these hypotheses remains scare or equivocal. In this study, we examine three proposed mechanisms—physiological constraints to bright light, reduced breeding activity and nest success, and …

Finding Music In Chaos: Designing And Composing With Virtual Instruments Inspired By Chaotic Equations, Landon P. Viator

LSU Doctoral Dissertations

Using chaos theory to design novel audio synthesis engines has been explored little in computer music. This could be because of the difficulty of obtaining harmonic tones or the likelihood of chaos-based synthesis engines to explode, which then requires re-instantiating of the engine to proceed with sound production. This process is not desirable when composing because of the time wasted fixing the synthesis engine instead of the composer being able to focus completely on the creative aspects of composition. One way to remedy these issues is to connect chaotic equations to individual parts of the synthesis engine instead of relying …

Sex-Related Differences In Brain Volumes And Cerebral Blood Flow Among Overweight And Obese Adults With Type 2 Diabetes: Exploratory Analyses From The Action For Health In Diabetes Brain Magnetic Resonance Imaging Study, Mark A. Espeland, Kathleen M. Hayden, Samuel N. Lockhart, Hussein N. Yassine, Siobhan Hoscheidt, Sevil Yasar, Jose A. Luchsinger, Rebecca H. Neiberg, Roberta Diaz Brinton, Owen Carmichael

Clinical Research Faculty Publications

Background: Sex may be an important modifier of brain health in response to risk factors. We compared brain structure and function of older overweight and obese women and men with type 2 diabetes mellitus. Methods: Cross-sectional cognitive assessments and magnetic resonance images were obtained in 224 women and 95 men (mean age 69 years) with histories of type 2 diabetes mellitus and overweight or obesity. Prior to magnetic resonance images, participants had completed an average of 10 years of random assignment to either multidomain intervention targeting weight loss or a control condition of diabetes support and education. Total (summed gray …

Natural Variation And Evolutionary Responses To Climate Change Stressors In Marine Invertebrates, Joanna Sarah Griffiths

LSU Doctoral Dissertations

Our rapidly changing climate is putting many species at risk of extinction and there is an urgent need to understand how species will respond to these changes. In this dissertation, I evaluate how three species of marine invertebrates (corals, oysters, and copepods) respond to stressful conditions in their current environments and how plasticity and evolutionary adaptation could alter their response to future climate change stressors. I first employed a space for time study to elucidate population differences in the response of cold-water corals, Balanophyllia elegans, to future ocean acidification. I found evidence that upwelling history (natural low pH exposure) influences …

Some Exit Time Estimates For Super-Brownian Motion And Fleming-Viot Process, Parisa Fatheddin

Journal of Stochastic Analysis

No abstract provided.

The Seasonal Evolution Of Albedo Across Glaciers And The Surrounding Landscape Of Taylor Valley, Antarctica, Anna Bergstrom, Michael N. Gooseff, Madeline Myers, Peter T. Doran, Julian M. Cross

Faculty Publications

© Author(s) 2020. The McMurdo Dry Valleys (MDVs) of Antarctica are a polar desert ecosystem consisting of alpine glaciers, ice-covered lakes, streams, and expanses of vegetation-free rocky soil. Because average summer temperatures are close to 0 °C, the MDV ecosystem in general, and glacier melt dynamics in particular, are both closely linked to the energy balance. A slight increase in incoming radiation or change in albedo can have large effects on the timing and volume of meltwater. However, the seasonal evolution or spatial variability of albedo in the valleys has yet to fully characterized. In this study, we aim to …

Effects Of Freshwater Inflow On Nekton Assemblages And Blue Crab Populations In Southeastern Louisiana, Caleb Benjamin Taylor

LSU Master's Theses

Estuaries along the northern Gulf of Mexico represent some of the most productive ecosystems in the world, providing vital habitat for many recreationally and commercially valuable species, including the blue crab, Callinectes sapidus. The mixing of fresh river and saline ocean water in coastal estuaries contribute to this productivity. Dominated by large river influences and consisting of multiple estuaries, Louisiana contributes the largest commercial fishery in the Gulf of Mexico, and remains, on average, the largest supplier of blue crabs in the nation. However, across southeast Louisiana, freshwater flow is largely dependent on Mississippi River discharge, which is highly …

Hyaluronic Acid-Cellulose Composites As Patches For Minimizing Bacterial Infections, Kelsey M. Lopez, Sudhir Ravula, Rocío L. Pérez, Caitlan E. Ayala, Jack N. Losso, Marlene E. Janes, Isiah M. Warner

Faculty Publications

Copyright © 2020 American Chemical Society. A facile method was used to synthesize biocomposites containing differing ratios of hyaluronic acid (HA) and cellulose (CEL). Based on the properties of the individual polymers, the resultant composite materials may have potentially great wound care properties. In the method outlined here, 1-butyl-3-methylimidazolium chloride ([Bmim][Cl]), a simple ionic liquid, was used as the sole solvent without chemical modifiers to dissolve the biopolymers at ratios of 1:1 and 2:1 HA to CEL. This method was completely recyclable since the ionic liquid, [Bmim][Cl], can be recovered. Results from spectroscopic measurements [Fourier transform infrared (FT-IR) and X-ray …