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Artificial Intelligence In Head And Neck Cancer: Towards Precision Medicine, Jacob Hagen, Logan Hornung, William Barham, Supratik Mukhopadhyay, Adam Bess, Kevin Contrera, Devraj Basu, Vlad Sandulache, Guillaume Spielmann, Sagar Kansara Sep 2025

Artificial Intelligence In Head And Neck Cancer: Towards Precision Medicine, Jacob Hagen, Logan Hornung, William Barham, Supratik Mukhopadhyay, Adam Bess, Kevin Contrera, Devraj Basu, Vlad Sandulache, Guillaume Spielmann, Sagar Kansara

Faculty Publications

Over the past 20 years, the capabilities of artificial intelligence (AI) have gained significant interest. While AI has been implemented to various degrees in several disciplines, its unique applications in head and neck cancer (HNC) remain underdeveloped. This narrative review examines the existing body of literature regarding the use of AI in HNC. Studies to date have demonstrated AI’s utility across multiple phases of the HNC treatment continuum. Despite its promise, integrating AI into clinical practice faces several challenges, including concerns about system integrity, generalizability, privacy, and bias. In this review, we address these challenges and offer insights into future …


Recovery Of The X-Ray Polarisation Of Swift J1727.8-1613 After The Soft-To-Hard Spectral Transition (Corrigendum) (Astronomy And Astrophysics (2024) 686 (L12) Doi: 10.1051/0004-6361/202450566), J. Podgorný, J. Svoboda, M. Dovčiak, A. Veledina, J. Poutanen, P. Kaaret, S. Bianchi, A. Ingram, F. Capitanio, S. R. Datta, E. Egron, H. Krawczynski, G. Matt, F. Muleri, P. O. Petrucci, T. D. Russell, J. F. Steiner, N. Bollemeijer, M. Brigitte, N. Castro Segura, R. Emami, J. A. García, K. Hu, M. N. Iacolina, V. Kravtsov, L. Marra, G. Mastroserio, T. Muñoz-Darias, E. Nathan, M. Negro, A. Ratheesh, N. Rodriguez Cavero, R. Taverna Sep 2025

Recovery Of The X-Ray Polarisation Of Swift J1727.8-1613 After The Soft-To-Hard Spectral Transition (Corrigendum) (Astronomy And Astrophysics (2024) 686 (L12) Doi: 10.1051/0004-6361/202450566), J. Podgorný, J. Svoboda, M. Dovčiak, A. Veledina, J. Poutanen, P. Kaaret, S. Bianchi, A. Ingram, F. Capitanio, S. R. Datta, E. Egron, H. Krawczynski, G. Matt, F. Muleri, P. O. Petrucci, T. D. Russell, J. F. Steiner, N. Bollemeijer, M. Brigitte, N. Castro Segura, R. Emami, J. A. García, K. Hu, M. N. Iacolina, V. Kravtsov, L. Marra, G. Mastroserio, T. Muñoz-Darias, E. Nathan, M. Negro, A. Ratheesh, N. Rodriguez Cavero, R. Taverna

Faculty Publications

(Figure presented) In Fig. 4, the X-ray hardness value for observation 8 was plotted using a count-based ratio instead of the energy-flux-based ratio used for other points in the figure. The correction of the position of this point in Fig. 4 does not affect any other figures, results, or conclusions in the paper.


How The Inter-Nucleon Force Shapes Emergent Collectivity And Imparts Uncertainties In Ab Initio Nuclear Observables, Kevin Becker Sep 2025

How The Inter-Nucleon Force Shapes Emergent Collectivity And Imparts Uncertainties In Ab Initio Nuclear Observables, Kevin Becker

LSU Doctoral Dissertations

The importance of collective motion in atomic nuclei has been well-established for many decades. Even before the advent of the nuclear shell model and its much-needed answers to surprising empirical phenomena, collectivity and surface deformation have played a vital role in broadening our knowledge. Reconciling the collective and single-particle camps into a unified description required tremendous strides in the application of group theory and advances in high-performance supercomputing, and thanks to these efforts the symmetry-adapted no-core shell model, or SA-NCSM, has developed into a reliable model for the study of deformed light and medium-mass nuclei. State-of-the-art calculations reveal remarkably simple …


Compound-Specific Isotope Records Of Dust Provenance And Hydroclimate In The North Pacific And Marginal Seas Of East Asia: Integrating N-Alkane Δ13c And Δd With Standardized Analytical Frameworks, Julian W. Traphagan Aug 2025

Compound-Specific Isotope Records Of Dust Provenance And Hydroclimate In The North Pacific And Marginal Seas Of East Asia: Integrating N-Alkane Δ13c And Δd With Standardized Analytical Frameworks, Julian W. Traphagan

LSU Doctoral Dissertations

This dissertation presents advancements in compound-specific isotope analysis (CSIA) through methodological innovation and paleoclimate reconstruction in Central and East Asia. Utilizing plant wax n-alkanes from International Ocean Discovery Program (IODP) and Ocean Drilling Program (ODP) sediment cores, this research reconstructs atmospheric circulation shifts responding to tectonic evolution and climate transitions since the Late Miocene.

Chapter 1 investigates hydrogen isotope compositions (δDwax) from IODP U1430 (Sea of Japan), ODP 886, and ODP 1208 (North Pacific) to trace dust provenance and hydroclimate changes since ~13 Ma. Results reveal persistently segmented source-to-sink systems: the Sea of Japan dominated by westerly …


Investigation Of Co-Current And Counter-Current Multiphase Flow In Upstream Drilling And Production Applications, Hazem Fleifel Aug 2025

Investigation Of Co-Current And Counter-Current Multiphase Flow In Upstream Drilling And Production Applications, Hazem Fleifel

LSU Doctoral Dissertations

In the domain of upstream Petroleum Engineering, the dynamics of co-current and counter-current multiphase flows present huge challenges, significantly impacting the efficiency of associated processes. This study investigates two specific applications concerning these flow behaviors, involving both laboratory experiments and transient computer simulations. This work investigates two distinct well control and production enhancement processes, involving multiphase flow dynamics: the bullheading kill procedure and liquid-assisted gas lift (LAGL).

The first topic (Topic 1) explores the bullheading process, a type of well control methods, by challenging the traditional understanding that gas removal efficiency increases monotonically with injection pump flow rate. Through 1D …


Designing A Data Collection And Visualization Toolkit For Scalable Tensor Algebra In Quantum Chemistry Applications, Epiya J. Ebiapia Aug 2025

Designing A Data Collection And Visualization Toolkit For Scalable Tensor Algebra In Quantum Chemistry Applications, Epiya J. Ebiapia

LSU Master's Theses

Large-scale quantum chemistry computations, such as those executed with the Tensor Algebra for Many-body Methods (TAMM) framework, require careful configuration of runtime parameters to achieve high performance and cost efficiency in high-performance computing (HPC) and cloud environments. Without effective performance analysis tools, researchers risk inefficient use of computational resources, leading to longer runtimes and higher costs.

To address this challenge, this thesis presents the design and implementation of a performance profiling and visualization toolkit for TAMM, developed as part of the DOE TEC4 project in collaboration with Pacific Northwest National Laboratory, Microsoft, and Louisiana State University. The toolkit collects detailed …


Exploring Longitudinal Stability Of Spatiotemporal Sequential Patterns By Means Of Autoencoder Schemes For Eeg Based Personal Identification, Muhammed E. Oztemel Aug 2025

Exploring Longitudinal Stability Of Spatiotemporal Sequential Patterns By Means Of Autoencoder Schemes For Eeg Based Personal Identification, Muhammed E. Oztemel

LSU Doctoral Dissertations

Robust personal identification remains a critical and challenging task in the digital era. Electroencephalography (EEG) offers a unique biometric modality that captures individual brain dynamics through complex neural signals. This dissertation proposes autoencoder (AE) based feature extraction and subject identification through these features. EEG recordings are first transformed into topographic maps to represent spatial brain activity. Consecutive topomaps are then concatenated to capture temporal transitions across frames. Convolutional autoencoders (CAEs) are used to learn spatial and temporal patterns, while domain-adaptive AEs are designed to model evoked potential based responses. Additionally, self-attention mechanism is incorporated to enhance feature representation. To analyze …


The Characteristic Function Of The Cube Of A Gaussian Random Variable, Andreas Boukas Aug 2025

The Characteristic Function Of The Cube Of A Gaussian Random Variable, Andreas Boukas

Journal of Stochastic Analysis

Using the spectral resolution of the multiplication operator on the Schwartz class of L2(R,C), we compute the characteristic function of the cube of a Gaussian random variable.


Novel Sequential Modeling Framework Improves Phytoplankton Biomass Predictions In Response To Multiple Environmental Stressors, Zhuyin Tong, Jiayu Guo, Yikai Liu, Lizhen Lin, Jixin Chen, Xin Liu, Bangqin Huang, Edward A. Laws, Wupeng Xiao Aug 2025

Novel Sequential Modeling Framework Improves Phytoplankton Biomass Predictions In Response To Multiple Environmental Stressors, Zhuyin Tong, Jiayu Guo, Yikai Liu, Lizhen Lin, Jixin Chen, Xin Liu, Bangqin Huang, Edward A. Laws, Wupeng Xiao

Faculty Publications

Understanding the impacts of multiple environmental stressors on phytoplankton biomass is crucial for predicting marine ecosystem responses under global climate change. This study employed a sequential modeling framework integrating principal component analysis, generalized additive models, and artificial neural networks to improve predictions of phytoplankton chlorophyll a concentrations in the Taiwan Strait. Analyzing a decadal dataset, we found that a 2°C rise in sea surface temperature and a 0.2 pH decline will each lead to an 11.3% reduction in chlorophyll a biomass, whereas nitrogen enrichment is expected to increase it by only 2.8%. The combined effects of these stressors will result …


Cell Death Helps To Stabilize Populations Of Prochlorococcus, P. Wang, E. A. Laws, C. Liang, X. Liu, J. Chen, Y. Zhong, C. Li, B. Huang Aug 2025

Cell Death Helps To Stabilize Populations Of Prochlorococcus, P. Wang, E. A. Laws, C. Liang, X. Liu, J. Chen, Y. Zhong, C. Li, B. Huang

Faculty Publications

Prochlorococcus is one of the dominant phytoplankton species in tropical and subtropical pelagic marine ecosystems. To maintain its population equilibrium in oligotrophic waters, the dominant species Prochlorococcus requires high loss rates to offset its high abundance and growth rates. While theoretical frameworks recognize multiple loss processes for Prochlorococcus (viral lysis, environmental stress, programmed cell death), prevailing population studies attribute main mortality to grazing. This oversight stems from in situ data gaps of non-grazing mortality processes. In this study, we firstly formulated simple differential equations that took account of population losses due to both grazing and cell death. We then used …


Measuring The Impact On Landscape And Sediment Transport Of Climate And Anthropogenic Influence In The Mississippi River Since 2000 Bce, Bailey Wycoff Jul 2025

Measuring The Impact On Landscape And Sediment Transport Of Climate And Anthropogenic Influence In The Mississippi River Since 2000 Bce, Bailey Wycoff

LSU Master's Theses

Understanding river dynamics is crucial to being able to interpret the geological history preserved in sediment deposited on continental margins, deltas, and alluvial plains. Sediment buffering can be a key control on the sediment flux to the ocean and involves sediment storage and recycling in flood plains. The efficiency of the transport varies depending on climatic and more recently anthropogenic influences. Sediment moving through meandering streams may be temporarily deposited in a point bar on the convex side of a meandering river. Meanders are sometimes cut off, creating an oxbow lake and filled in. The area of study, False River, …


A Multi-Scale Numerical Analysis Of Wave Propagation Through Coastal Vegetation Using Proteus & Xbeach, Cole M. Statler Jul 2025

A Multi-Scale Numerical Analysis Of Wave Propagation Through Coastal Vegetation Using Proteus & Xbeach, Cole M. Statler

LSU Master's Theses

Coastal vegetation attenuates waves in the nearshore zone and protects shorelines from storm surge and wave action. It also traps nutrients and sediment, and participates in the formation of land over longer time scales. These features of vegetation make it a common component of nature-based engineering projects. Interaction of water waves and flow with vegetation, however, can involve unsteady and turbulent flow, non-hyrdostatic pressure effects, and air entrainment that can hinder the use of simple parametric representations of vegetation drag. XBeach, a one- and two-dimensional production model applies reduced-order methods, prioritizing computational efficiency. Vegetation is represented in XBeach as a …


Essays On Stablecoins’ Stability, Ravi Joshi Jul 2025

Essays On Stablecoins’ Stability, Ravi Joshi

LSU Doctoral Dissertations

In this dissertation, I present three independent essays that contribute to the literature on stablecoins, the run-on stablecoin (Terra), and the information narrative surrounding the run. The first essay offers a comprehensive overview of the stablecoin ecosystem, the structural frictions that challenge peg maintenance, and the evolving regulatory landscape governing stablecoin issuance and use. In the second essay, I investigate the collapse of the TerraUSD (UST) algorithmic stablecoin and provide evidence that the collapse mimicked a run by demonstrating liquidity shortages on centralized exchanges. I show that Terra’s arbitrage mechanism broke on May 7, 2022, and that sustained price deviations …


Adaptive Multi-Agent Reinforcement Learning For Electric Vehicle Charging Optimization Under Dynamic Traffic Conditions, Shaghayegh Rabbanian Jul 2025

Adaptive Multi-Agent Reinforcement Learning For Electric Vehicle Charging Optimization Under Dynamic Traffic Conditions, Shaghayegh Rabbanian

LSU Master's Theses

Electric vehicle (EV) charging optimization is a critical challenge in sustainable transportation. This study focuses on three fundamental questions: (1) when is the best time to charge an EV, (2) where is the optimal charging location, and (3) how should charging be planned considering navigation and routing decisions. Our primary objective is to determine the optimal time and location for EV charging while accounting for key factors such as real-time traffic conditions, spatial distribution of charging stations, and EV-specific attributes such as state of charge (SOC), driving range, and efficiency. To develop a robust and adaptive EV charging recommendation system, …


Patterns And Processes Behind Secretive Marshbird Movement, Abundance, And Distribution Across Southeastern Louisiana, Leah Moran Jul 2025

Patterns And Processes Behind Secretive Marshbird Movement, Abundance, And Distribution Across Southeastern Louisiana, Leah Moran

LSU Doctoral Dissertations

Restoration and conservation of coastal Louisiana hinges on understanding the patterns and processes underlying habitat heterogeneity on the landscape and therefore the species that inhabits this region, including secretive marshbirds. Elusive in nature, this guild of birds has evolved under dynamic hydroperiods, and myriad plant communities present within wetlands. Only recently, however, has research focused on the role of hydrologic dynamics and vegetative structure and distribution on abundance, movement and detection of marshbirds, specifically within southeastern Louisiana. This study aimed to quantify the ecological patterns and processes, particularly hydrologic processes and landscape structure, driving breeding secretive marshbird movement, abundance and …


Operator Information Quantities Of Semigroups Associated With Functions Of The Number Operator, Ryo Inayoshi, Kimiaki Saito Jul 2025

Operator Information Quantities Of Semigroups Associated With Functions Of The Number Operator, Ryo Inayoshi, Kimiaki Saito

Journal of Stochastic Analysis

In this paper, we present recent developments on the operator information quantity acting on white noise functionals. In particular, we give a stochastic expression of the operator information quantity of a semigroup generated by some function of the number operator through a white noise delta distribution centered at an infinite dimensional Ornstein-Uhlenbeck process.


Investigating The Relationships Among Suspended Sediment Concentration, And Marsh Edge Erosion In Barataria Bay, La, Lily Vowels Jul 2025

Investigating The Relationships Among Suspended Sediment Concentration, And Marsh Edge Erosion In Barataria Bay, La, Lily Vowels

LSU Master's Theses

Barataria Bay, Louisiana, USA exhibits a unique microtidal, wind-driven hydrodynamic climate where extensive levee infrastructure throughout Louisiana has starved Barataria Bay and similar interdistributary bays of the historic levels of terrigenous sediment import. This has contributed to extreme coastal wetland loss in Louisiana. This project seeks to understand how hydrodynamic and meteorological conditions are linked to sediments’ fate after erosion from the marsh edge. Specifically, this project seeks to differentiate the roles of wave resuspension and marsh edge erosion (MEE) in sediment dynamics in Barataria Bay. An acoustic wave and current profiler (AWAC) was used to capture hydrodynamic conditions, and …


Novel Tools And Datamining Techniques To Visualize And Interpret Historical Sugarcane Datasets, Zachary A. Taylor Jul 2025

Novel Tools And Datamining Techniques To Visualize And Interpret Historical Sugarcane Datasets, Zachary A. Taylor

LSU Master's Theses

Heritable genetic variation is an essential raw ingredient of variety development programs. This variation is acted upon via selection by identifying elite progeny that can be utilized agronomically or exploited as parents. Sugarcane breeders are tasked with creating optimal genetic variation through crossing. Prior knowledge of pedigree and parental performance allows breeders to discern which crosses to prioritize, since the time to make crossing decisions and the space to evaluate tens and thousands of progenies are both limited resources in sugarcane variety development programs. In this project, we have updated and validated the U.S. sugarcane pedigree …


Dose Characterization Of Galactic Cosmic Rays In The Human Brain: A Phits-Based Study With A Segmented Anatomical Phantom, Shanice N. Manning Jul 2025

Dose Characterization Of Galactic Cosmic Rays In The Human Brain: A Phits-Based Study With A Segmented Anatomical Phantom, Shanice N. Manning

LSU Master's Theses

Astronauts aboard the International Space Station (ISS) are chronically exposed to a complex space radiation environment composed of galactic cosmic rays (GCR), solar particles, and Earth's trapped radiation. These high-energy particles interact with spacecraft shielding, producing secondary particles that can penetrate inside and deposit energy in sensitive tissues. Although animal studies have been useful in assessing space radiation risks, anatomical and physiological differences limit their applicability to human anatomy especially neuroanatomy. To address this gap, we developed a computational framework to model radiation dose distribution within the human brain using Monte Carlo simulations in Particle and Heavy Ion Transport code …


Quasistatic Peridynamics, Existence Of Unique Solution In The Presence Of Damage, Nuwanthi N. Samarawickrama Jul 2025

Quasistatic Peridynamics, Existence Of Unique Solution In The Presence Of Damage, Nuwanthi N. Samarawickrama

LSU Doctoral Dissertations

A mathematical model for damage propagation based on nonlocal potentials is developed within the framework of peridynamics. This model is applied to simulate damage evolution in cyclically loaded structures. By neglecting inertial effects, a well-posed quasistatic formulation for cyclic loading is obtained.\\ The resulting equation is expressed as a nonlocal and nonlinear integral operator that couples damage evolution to the deformation field.\\ This coupling occurs through the product of a damage factor and the derivative of a force potential. The damage factor ranges between zero and one, where one represents undamaged material and zero indicates complete damage.\\ It serves to …


A Comparative Case Study Of Mentoring Practices By National Board Certified And Non-Certified Teacher Mentors, Bethany Mcclure Jul 2025

A Comparative Case Study Of Mentoring Practices By National Board Certified And Non-Certified Teacher Mentors, Bethany Mcclure

LSU Doctoral Dissertations

As preservice teacher candidates engage in field experiences that shape their development of teacher identity, it is important to examine their perceptions of the mentoring process. This study explored how preservice teacher candidates construct their own knowledge about mentoring as a process, as well as explored the perceptions of mentor teachers, both National Board Certified, and non-National Board Certified, as they facilitated the learning and growth of their mentees. Many prior studies on the mentoring process exist, however, a gap in the literature that was identified and explored through this study included the impact that National Board Certified Teachers have …


Digital Forensics And Ai: Artifact Analysis And Using Ai In The Forensics Domain, Clinton Joel Walker Jul 2025

Digital Forensics And Ai: Artifact Analysis And Using Ai In The Forensics Domain, Clinton Joel Walker

LSU Doctoral Dissertations

Digital Forensics (DF) is a field of forensic science focusing on the acquisition, authentication, and analysis of digital evidence while maintaining integrity of that data. DF analysts use forensic tools to parse large volumes of data for investigations and depend on them for identification of pertinent digital evidence in vast amounts of data. Keeping up with innovations and ever-expanding data volumes is a constant challenge for these investigators. The prevalence of Artificial Intelligence (AI) in everyday computing is rapidly expanding, with the use of Machine Learning (ML) and Large Language Models (LLM)s becoming increasingly commonplace. Innovations in technology bring new …


Towards Leveraging Social Media Data For Fostering Collaborations Among Non-Profits, Monazil Chowdhury Jul 2025

Towards Leveraging Social Media Data For Fostering Collaborations Among Non-Profits, Monazil Chowdhury

LSU Doctoral Dissertations

Nonprofit organizations serve a crucial role in tackling a wide range of significant social, environmental, and economic issues. But it is often hard to get a clear picture of their work because their information is spread out and it is difficult to see how they are collaborating. To address this issue we developed a web-based tool to collect scattered data—from a variety of sources, such as the IRS, social media, and the Census, into one easy-to-use resource. The tool begins by taking IRS records and geocoding each nonprofit’s physical address With its coordinates. It then retrieves census tract information from …


A Performance Guide To Christos Hatzis’ Songs On Poems By Sappho, Maria E. Thomas Jul 2025

A Performance Guide To Christos Hatzis’ Songs On Poems By Sappho, Maria E. Thomas

LSU Doctoral Dissertations

Abstract

Christos Hatzis’ Three Songs of Poems by Sappho (1999) represents a compelling yet understudied contribution to contemporary art song repertoire. This study examines Hatzis’ settings of Sappho’s Fragments 1, 16, and 44, offering both scholarly analysis and practical performance guidance to make the cycle more accessible to singers and scholars. Through musical and textual analysis, this project reveals how Hatzis bridges ancient Greek lyric poetry with modern compositional techniques. The study demonstrates his innovative approach to word painting, rhythmic flexibility, and extended tonality, showing how these elements honor Sappho’s intimate first-person voice while creating a distinctive 20th-century art song …


The Design And Effect Of Continuum Robot Compliance On Locomotion, Parsa Molaei Jul 2025

The Design And Effect Of Continuum Robot Compliance On Locomotion, Parsa Molaei

LSU Doctoral Dissertations

Continuum robots, due to their compliant structures and ability to navigate through constrained environments, offer significant advantages in applications requiring safe physical interaction and dexterous motion. However, challenges related to limited structural stiffness, payload capacity, and precise control remain open problems in the field. This dissertation presents novel contributions aimed at addressing these limitations through two main actuation units of continuum robots: tendon-driven continuum robots (TDCRs) and concentric tube robots (CTRs). In the first part, we focus on methods to improve the stability and modify the stiffness of the TDCR. A tendon decoupling strategy is introduced for planar TDCRs. The …


Quantitative Boundary Doubling Estimates For Elliptic Equations, Jack Dalberg Jul 2025

Quantitative Boundary Doubling Estimates For Elliptic Equations, Jack Dalberg

LSU Doctoral Dissertations

We present an approach for obtaining quantitative boundary doubling inequalities for elliptic equations with Neumann boundary conditions. Carleman estimates are used to prove three-ball inequalities, which are then used to prove quantitative doubling inequalities, with bootstrapping from the interior to the boundary. This approach is illustrated by its application to the Laplace eigenvalue problem with homogeneous Neumann boundary conditions, where sharp doubling inequalities are recovered.

When then consider a equation with non homogeneous Neumann boundary conditions. By following the approach, we are able to obtain potentially sharp results. Finally, we are able to get an improvement on previously obtained results …


Gain Threshold Optimization Using Fano Resonance, Alina Oktiabrskaia Jul 2025

Gain Threshold Optimization Using Fano Resonance, Alina Oktiabrskaia

LSU Doctoral Dissertations

The study of resonances in electromagnetics plays a critical role in the design of optical systems. This dissertation investigates the interaction between resonance and gain in optical structures to establish a universal principle for achieving ultra-low-threshold lasing. Through the analysis of geometric symmetries, material properties, and coupling mechanisms, this research develops prototype structures applicable to a wide range of optical and electromagnetic systems. A range of models is considered, starting from a simple onedimensional string-resonator system (based on the model of H. Lamb), then advancing to two- and three-dimensional waveguide models, and culminating with a realistic high-contrast model in open …


Assessing Natural Resources Conservation Service (Nrcs) Impacts On Rice And Soybean Efficiency In The Mid-South, Ayodeji Samuel Ayiti Jul 2025

Assessing Natural Resources Conservation Service (Nrcs) Impacts On Rice And Soybean Efficiency In The Mid-South, Ayodeji Samuel Ayiti

LSU Master's Theses

The study investigates how the Mid-South region of the U.S. rice and irrigated soybean production efficiency is influenced by (NRCS) incentives. To evaluate the effect of crop insurance, subsidies, and conservation incentives on lowering inefficiency, this study used a stochastic frontier model (SFA). The dataset covered the years 2010 – 2023, which allowed for a thorough evaluation of efficiency trends over time. While crop insurance programs reduce inefficiency in rice production, it shockingly increases inefficiency in soybean production, according to the study, which highlights the disparate effects of net support (insurance-subsidy).

The results show that while external factors like changes …


The Search For Magnetar Giant Flares In Archival Gamma-Ray Burst Data To Constrain Their Rates And Energetics, Aaron Trigg Jul 2025

The Search For Magnetar Giant Flares In Archival Gamma-Ray Burst Data To Constrain Their Rates And Energetics, Aaron Trigg

LSU Doctoral Dissertations

Magnetar giant flares are rare, extremely bright bursts of gamma-rays from highly magnetized neutron stars. These events are difficult to identify because, at extragalactic distances, they can appear similar to other astrophysical phenomena. Only a handful have been confidently identified to date, limiting our understanding of their origin and physical properties. This dissertation focuses on expanding the sample of known events and enabling a more detailed characterization of their observational features. We report on two newly identified examples, GRB 180128A and GRB 231115A, that are consistent with a magnetar origin based on their spectral properties and association with nearby star-forming …


Investigation Of Subcellular Damage And Long-Term Non-Cancerous Cardiovascular Effects Following Whole-Body Photon Irradiation, Nousha Afshari Jul 2025

Investigation Of Subcellular Damage And Long-Term Non-Cancerous Cardiovascular Effects Following Whole-Body Photon Irradiation, Nousha Afshari

LSU Doctoral Dissertations

Current radiobiological models focus primarily on nuclear DNA damage and fail to fully explain radiation-induced noncancerous health effects. This dissertation investigates whether non-nuclear subcellular structures contribute to radiation-induced biological damage through experimental biomarker analysis and computational microdosimetry. The central hypothesis posits that whole-body photon irradiation results in subcellular non-nuclear damage, specifically increased circulating mitochondrial DNA concentrations, that correlates with radiation dose and long-term noncancerous effects such as cardiovascular disease.

Specific Aim 1 measured mitochondrial and nuclear DNA concentrations in banked blood samples from 72 Chinese rhesus macaques that previously received whole-body photon irradiation ($0-10$ Gy) from Cobalt-60 or LINAC sources. …