Digital Commons Network^™

Modulating The Aqueous Micellar Reorganization Of Sequence-Defined Ionic Peptoid Block Copolymers By Ionizable Monomer Position And Solution Ph, Bailee N. Barrett, Pedram Azizihariri, Vijay T. John, Donghui Zhang

Faculty Publications

The micellar aggregation of singly charged sequence-defined ionic peptoid block copolymers can be finely tuned by adjusting the position of the ionizable monomer along the chain and varying the solution pH. The pH-induced structural reorganization of these micelles was found to depend on the position of the ionizable monomer along the chain, influencing the balance of the hydrophobic interactions, excluded volume effect, and electrostatic forces (i.e., charge repulsion, solvation of the ionic monomers, counterion association) that govern the micellar structure. As the solution pH increases, positioning the ionizable monomer closer to the junction of the hydrophobic and hydrophilic blocks causes …

Preface, José Luis Da Silva, Un Cig Ji, Aurel Stan

Journal of Stochastic Analysis

No abstract provided.

Empowering Sustainable Development: Solar Energy For Enhanced Weather Resilience, Aly Mousaad Aly

Faculty Publications

This paper examines the impact of photovoltaic (PV) panels on wind loads in low-rise buildings with gable roofs, emphasizing their potential to promote sustainable energy solutions while improving structural integrity. We hypothesize that PV panels can effectively reduce wind-induced forces on roofing components. Experiments using a 1:7.5 scale model in an open-jet wind facility compared bare roofs to those equipped with PV panels across three configurations. Results show that PV panels can decrease total wind forces on the roof by 45% to 63%, depending on configuration and wind direction. These findings suggest that additional structural reinforcement may not be necessary …

A Numerical Assessment Of Ocean Alkalinity Enhancement Efficiency On A River-Dominated Continental Shelf—A Case Study In The Northern Gulf Of Mexico, Yanda Ou, Z. George Xue, Xinping Hu

Faculty Publications

A robust high-resolution coupled hydrodynamic-biogeochemical model was applied to the northern Gulf of Mexico to assess the efficiency of river- and ocean-sourced ocean alkalinity enhancement (OAE). Sensitivity tests indicate that the effectiveness of OAE-induced CO2 uptake is primarily influenced by the amount of alkalinity introduced and local wind-driven mixing, with the former determining the overall uptake and the latter affecting short-term variability. Compared to ocean-sourced OAE (direct ocean release), river-sourced OAE (elevated river alkalinity) is more effective and sustainable. River-sourced OAE has higher CO2 uptake efficiency with reduced spatial and temporal uncertainty and greater overall CO2 uptake. For river-sourced OAE, …

A Data-Driven Approach To Enhance The Prediction Of Bacteria–Metabolite Interactions In The Human Gut Microbiome Using Enzyme Encodings And Metabolite Structural Embeddings, Gopal Srivastava, Michal Brylinski

Faculty Publications

Background: The human gut microbiome is critical for host health by facilitating essential metabolic processes. Our study presents a data-driven analysis across 312 bacterial species and 154 unique metabolites to enhance the understanding of underlying metabolic processes in gut bacteria. The focus of the study was to create a strategy to generate a theoretical (negative) set for binary classification models to predict the consumption and production of metabolites in the human gut microbiome. Results: Our models achieved median balanced accuracies of 0.74 for consumption predictions and 0.95 for production predictions, highlighting the effectiveness of this approach in generating reliable negative …

Rapid Mid-Infrared Spectral Timing With Jwst: Grs 1915+105 During An Mir-Bright And X-Ray-Obscured State, P. Gandhi, E. S. Borowski, J. Byrom, R. I. Hynes, T. J. Maccarone, A. W. Shaw, O. K. Adegoke, D. Altamirano, M. C. Baglio, Y. Bhargava, C. T. Britt, D. A.H. Buckley, D. J.K. Buisson, P. Casella, N. Castro Segura, P. A. Charles, J. M. Corral-Santana, V. S. Dhillon, R. Fender, A. Gúrpide, C. O. Heinke, A. B. Igl, C. Knigge, S. Markoff, G. Mastroserio, M. L. Mccollough, M. Middleton, J. M. Miller, J. C.A. Miller-Jones, S. E. Motta, J. A. Paice, D. D. Pawar, R. M. Plotkin

Faculty Publications

We present mid-infrared (MIR) spectral-timing measurements of the prototypical Galactic microquasar GRS 1915+105. The source was observed with the Mid-Infrared Instrument (MIRI) onboard JWST in June 2023 at an MIR luminosity LMIR ≈ 10³⁶ erg s⁻¹ exceeding past infrared levels by about a factor of 10. In contrast, the X-ray flux is much fainter than the historical average, in the source’s now-persistent ‘obscured’ state. The MIRI low-resolution spectrum shows a plethora of emission lines, the strongest of which are consistent with recombination in the hydrogen Pfund (Pf) series and higher. Low-amplitude (∼1 per cent) but highly significant peak-to-peak …

Nodal Finite Element Approximation Of Peridynamics, Prashant K. Jha, Patrick Diehl, Robert Lipton

Faculty Publications

This work considers the nodal finite element approximation of peridynamics, in which the nodal displacements satisfy the peridynamics equation at each mesh node. For the nonlinear bond-based peridynamics model, it is shown that, under the suitable assumptions on an exact solution, the discretized solution associated with the central-in-time and nodal finite element discretization converges to a solution in the L² norm at the rate C1Δt+C2h²/ϵ². Here, Δt, h, and ϵ are time step size, mesh size, and the size of the horizon or nonlocal length scale, respectively. Constants C1 and C2 are independent of h …

Defect Bound States In The Continuum Of Bilayer Electronic Materials Without Symmetry Protection, Daniel Massatt, Stephen P. Shipman, Ilya Vekhter, Justin H. Wilson

Faculty Publications

We analyze a class of bound defect states in the continuum electronic spectrum of bilayer materials, which emerge independent of symmetry protection or additional degrees of freedom. Taking graphene as a prototypical example, our comparative analysis of AA- and AB-stacked bilayer graphene demonstrates that these states originate from the intrinsic algebraic structure of the tight-binding Hamiltonian when trigonal warping is neglected rather than any underlying symmetry. The inclusion of trigonal warping and higher-order hoppings broadens the bound states into long-lived resonances. This discovery provides a distinct pathway to defect and band-structure engineering. We conclude with a proposed protocol for observing …

Orbifolds And Minimal Modular Extensions, Chongying Dong, Siu Hung Ng, Li Ren

Faculty Publications

Let V be a simple vertex operator algebra and G a finite automorphism group of V such that V^G is regular, and the conformal weight of any irreducible g-twisted V-module N for g∈G is nonnegative and is zero if and only if N=V. It is established that if V is holomorphic, then the V^G-module category CV^G is a minimal modular extension of E=Rep(G), and is equivalent to the Drinfeld center Z(VecG^α) as modular tensor categories for some α∈H³(G,S¹) with a canonical embedding of E. Moreover, the collection Mv(E) of equivalence …

Beyond Water Surface Profiles: A New Iterative Methodology For 2d Model Calibration In Rivers Using Velocity Data From Multiple Cross-Sections, Fabian Rivera-Trejo, Gabriel Soto-Cortes, Kory M. Konsoer, Eddy J. Langendoen, Gaston Priego-Hernandez

Faculty Publications

Observed longitudinal water-surface profiles are commonly used to calibrate river hydrodynamic models, relying on assumptions of lateral uniformity in water surface elevation and velocity distribution. While suitable for 1D models, this approach has limitations in regard to 2D model calibration. When 2D flow measurements are available, a more robust quantitative evaluation is necessary to assess model accuracy. This study introduces a novel methodology to improve 2D model calibration and evaluate performance. High-resolution bathymetric and hydrodynamic data collected with a multibeam echosounder (MBES) and acoustic Doppler current profiler (ADCP) were aligned to compare observed and simulated flow velocities at matching spatial …

Development And In Vitro Evaluation Of A Lignin-Plga Nanocarrier For Florfenicol Delivery, Emilia Trif, Carlos E. Astete, Sumit Libi, Emoke Pall, Septimiu Tripon, Cristina Coman, Diana Olah, Adrian Valentin Potârniche, Cristina M. Sabliov, Constantin Cerbu

Faculty Publications

Florfenicol (FF) is a widely used antimicrobial in veterinary medicine because of its broad antimicrobial activity, although it has certain limitations and raises concerns about the development of antimicrobial resistance genes. These limitations highlight the need to explore novel drug with controlled release systems to enhance the therapeutic efficacy of FF, while minimizing the potential for resistance development. This study introduces an innovative approach for the design, synthesis, and evaluation of lignin-poly(lactic-co-glycolic) acid (PLGA)-FF nanoparticles. By leveraging the properties of PLGA and lignin, this study aimed to augment the solubility, stability, and bioavailability of FF, thereby enabling dosage reduction and …

Assessing Water Quantity And Quality In The Mississippi River Valley Alluvial Aquifer And Coastal Louisiana Through Integrated Airborne Electromagnetic And Borehole Data, Michael George Henin Attia Khalil

LSU Doctoral Dissertations

Numerical modeling has contributed significantly to the understanding of groundwater systems. Many challenges are associated with constructing groundwater models which include an accurate understanding of the geology and aquifer parameters estimation. Traditionally boreholes are a successful way to capture geological features, however, boreholes often have sparse data. Airborne electromagnetic (AEM) data allows for efficient and cost-effective surveying of large areas, providing valuable information about the subsurface electrical resistivity. By bridging the gap between boreholes, AEM data offers a broader view of the aquifer system's structure and heterogeneity. However, interpreting geophysical AEM data has uncertainties. Developing a framework to apply the …

Bim-Intergrated Simulation Framework For Carbon Emission During Construction, Philip Cheffa

LSU Master's Theses

The construction sector is a major contributor to global carbon emissions, responsible for approximately 39% of energy-related emissions. This research introduces an innovative BIM-integrated simulation framework to estimate and manage carbon emissions during construction. Leveraging 4D Building Information Modeling (BIM), the study integrates critical dimensions of time, cost, and carbon emissions into a cohesive framework. A mathematical model was developed to quantify carbon emissions from construction activities, including equipment utilization and workforce energy consumption, with RSMeans data providing cost and productivity metrics.

The framework was validated through a case study that compared alternative work schedules utilizing different resources to evaluate …

The Full Range Leadership Model (Frlm): Department Head Perceptions Of Leadership Style And Development, Stephanie Elaine Heroman

LSU Doctoral Dissertations

The purpose of this study is to discover the perceived leadership styles of department heads as categorized by the Full Range Leadership Model (FRLM), developed by Avolio and Bass (1991). The FRLM categorizes leadership style along a continuum, from laissez-faire leadership, to transactional leadership, and ultimately transformational leadership. Even though department heads occupy a pivotal leadership role, many do not have formal leadership training, and instead rise to power through disciplinary expertise. This study will collect data on the experiences contributing to the development of leadership style in department heads. Understanding the leadership styles and experiences of department heads will …

Temporal Scales Of Sediment Accumulation, Mass Wasting, And Stratigraphy Across The Mississippi River Delta Front, Jeffrey E. Duxbury

LSU Doctoral Dissertations

The Mississippi River Delta Front (MRDF) is a subaqueous apron of rapidly deposited, weakly

consolidated sediment extending from the subaerial portions of the Mississippi River’s Birdsfoot Delta, historically known for sediment transport via mass wasting. To better understand the spatial and temporal dynamics of processes influencing the MRDF, 29 cores ranging from 5.8 to 8.71 meters in length were collected from the South Pass (SP) and Southwest Passes (SWP). These cores targeted specific depositional environments, including the undisturbed topset apron, medial mudflow gully, mudflow lobe, and prodelta. The cores were analyzed along their full lengths for gamma density, grain size, …

Spin Caloritronics As A Probe Of Nonunitary Superconductors, Taiki Matsushita, Takeshi Mizushima, Yusuke Masaki, Satoshi Fujimoto, Ilya Vekhter

Faculty Publications

Superconducting spintronics explores the interplay between superconductivity and magnetism, sparking substantial interest in nonunitary superconductors as a platform for magneto-superconducting phenomena. However, identifying nonunitary superconductors remains challenging. We demonstrate that spin current driven by thermal gradients sensitively probes the nature of the condensate in nonunitary superconductors. Spin polarization of the condensate in momentum space induces the superconducting spin Seebeck effect, where a spin current is generated along thermal gradients without a thermoelectric charge current. Notably, the nonvanishing superconducting spin Seebeck effect provides a smoking gun evidence of nonunitary superconductivity because it reflects the spin polarization of the condensate in momentum …

Thermal Noise Measurement Below The Standard Quantum Limit, Ronald Pagano

LSU Doctoral Dissertations

Quantum mechanics places sensitivity restrictions on physical measurements. These limitations manifest themselves in interferometric force and displacement measurements as uncertainty both in the photon number measured at a photodetector (shot noise), and in the quantum radiation pressure applied to the interferometer (quantum back action noise manifested as quantum radiation pressure noise). The balance between shot noise and quantum radiation pressure noise imposes the Standard Quantum Limit (SQL). A large body of work has been dedicated to measuring these quantum effects and mitigating them. Owing to the inherently small scale at which quantum effects are visible, classical effects must be subverted …

Improving Fertilizer Efficiency In Containerized Nursery Production Through Substrate Temperature Management Techniques, Ashley R. Edwards

LSU Master's Theses

Resource efficiency, particularly regarding mineral nutrients, is a critical factor in the long-term success of the nursery industry. Fertilizer release is controlled by water and temperature in container-grown ornamental nursery production systems. Thus, it was hypothesized that pragmatic management of substrate temperature and moisture could extend the longevity of controlled-release fertilizer (CRF) in a container system. This study was conducted to determine the effect of irrigation scheduling, container color, and stratified substrates on substrate temperature and the subsequent use and longevity of CRF in a crop production setting. ‘Limelight’ Hydrangea (Hydrangea paniculata) liners were planted in either black …

State-Of-Charge Estimation Using Deep Learning For Electric Vehicles, Samer Yahya Ribhe Tahboub

LSU Master's Theses

This thesis investigates the application of deep learning models for State of Charge (SOC) estimation in Battery Management Systems (BMS) for electric vehicles (EVs), focusing on optimizing EV range, lifespan, and performance while addressing challenges like range anxiety. The study explores three deep learning architectures—Long Short-Term Memory (LSTM), Bidirectional LSTM (BiLSTM), and Gated Recurrent Unit (GRU)—each designed to capture complex temporal dependencies in battery data. The LSTM model is trained on EV battery data, including voltage, current, temperature, and SOC, providing a strong baseline for SOC estimation. The BiLSTM model enhances accuracy by processing data in both forward and backward …

Non-Catalytic Direct Partial Oxidation Of Methane To Methanol In A Wall-Coated Microreactor, Kelly Cohen

LSU Doctoral Dissertations

This project used an integrated mixer-reactor-heat exchanger microtube scalable module for the non-catalytic direct partial oxidation of methane in natural gas to methanol at elevated pressures (70-95 bar), reaction temperatures of 380-460C, reactant methane:air ratios of 0.5-4.4 and reaction zone residence times on the order of 1 min. Currently, methane in remote locations is often flared in large quantities rather than transported or converted to the more easily transportable methanol. However, if this gaseous methane were converted to liquid methanol at the wellhead, it could be transported in ways other than pipeline or used onsite.

Additionally, methane is currently converted …

Flood Risk And Mitigation Calculator Tool To Support Decision-Making For Enhancing Community Resilience: A Case Study Of The U.S.A. Gulf Coastal Region, Rubayet Bin Mostafiz, Ayat Al Assi, Arash Taghinezhad, Carol J. Friedland, Robert V. Rohli, Md Adilur Rahim, Christopher T. Emrich, Melanie Gall, Eric Johnson

Faculty Publications

Real-estate websites make it easy to find and access information about a home. Information on property value, square footage, number of rooms, quality of schools, crime rates, and more is readily available. Some of these platforms have begun integrating climate-related risks in generic ways. However, this information provides limited if any actionable value and is unlikely to guide people’s decision-making on buying or renting a home, deciding where to vacation, or investing in a property. Making residents aware of the natural hazard risks to which their homes may be exposed is an important component of making communities more resilient. Both …

Trajectory Of Coastal Wetland Soil Physical And Microbial Properties 6+ Years After Thin Layer Placement Sediment Amendment, Jacob Z. Cheng, Jacob F. Berkowitz, John R. White

Faculty Publications

The intentional thin layer placement (TLP) of dredged sediment is an increasingly popular approach to maintaining marsh elevation and restoring degraded marshes, which can improve conditions for vegetation establishment. Prior TLP restoration projects, assessed shortly after construction, evaluated soil, hydrology, plant, and faunal responses. However, few long-term studies (>3 yrs) investigate TLP-induced shifts in soil properties and especially properties related to biogeochemical cycling. In response, this study revisited a salt marsh 6+ years after TLP restoration and determined both soil physiochemical and microbial properties related to plant growth (nitrogen (N) mineralization) and water quality improvement (denitrification). Data were compared …

The Impact Of Seasonal Hydrological Disturbances On The Presence And Formation Of Toxic Cyanobacteria Blooms In Coastal Louisiana, Courtney Nicole Hammond, Sibel Bargu, Caitlin R.R. Turner, Matthew Hiatt, John R. White

Faculty Publications

Estuaries in the Gulf, especially Lake Pontchartrain Estuary in southeastern Louisiana, USA, are experiencing significant changes due to climate change and coastal restoration efforts. Lake Pontchartrain Estuary receives nutrient-rich Mississippi River water through a controlled diversion called Bonnet Carré Spillway (BCS), which has been associated with toxic cyanobacterial blooms (cyanoHABs). This study examines the seasonal factors influencing cyanoHABs in the Lake Pontchartrain Estuary when the BCS is closed, addressing gaps in the understanding of HABs related to other physical drivers. Field samples collected in 2021, during the closure of the spillway, revealed significant evidence of seasonal variations in cyanoHAB formation. …

Photogrammetric Determination Of Movement Speed Of Invasive Indo-Pacific Lionfish In The Florida Keys, Neal Kolonay, Cassandra N. Glaspie

Faculty Publications

As a key determinant of how efficiently lionfish (Pterois sp.) locate and capture prey, swimming speed plays a crucial role in shaping the predator-prey interactions and broader ecological dynamics within the invaded ecosystems. Swimming speed on a small temporal and spatial scale is difficult to measure because of the need for precise measurements of both distance and duration of the behavior. Using photogrammetry by way of stereo-camera setups is ideal for analyzing the minutiae of lionfish behaviors because it can include the benefits of remote video traps coupled with precise measurements of movements in three-dimensional space and time. The primary …

Comparison Of Two Benthic Assemblage Sampling Gears For Use On Intertidal Oyster Reefs In Louisiana, Finella M. Campanino, Stephanie K. Archer, Jillian C. Tupitza, Cassandra N. Glaspie, Megan K. La Peyre

Faculty Publications

Background: Estuarine biodiversity plays a vital role in supporting ecosystem functions yet remains threatened by climate change and anthropogenic activity. Tracking and identifying estuarine biodiversity trends helps management ensure long-term provisions of human and environmental benefits by contributing to the estimation of habitat loss and the monitoring of restoration and conservation progress. However, results obtained using different sampling gears and different biodiversity metrics may lead researchers to reach different conclusions, which can lead to uncertainty in the actual state of the ecosystem-level biodiversity. Sampling benthic biodiversity in complex estuarine habitats, such as oyster reefs, is particularly challenging because no one …

Primary Processes Of Depolymerization Of Lignin Dispersed Into Gas Phase, Marwan Y. Rezk, Mohamad Barekati-Goudarzi, Divine Nde, Dorin Boldor, Slawomir Lomnicki, Stephania Cormier, Lavrent Khachatryan

Division of Basic Science Faculty Publications

The primary depolymerization processes of hydrolytic lignin (HL) are examined, focusing on the formation of intermediate oligomers and bulky environmentally persistent free radicals (EPFRs). Fragmentation of HL was conducted in a continuous atomization (CA) fast flow reactor, where HL, dissolved in a 9:1 acetone-to-water solution, was dispersed. Results indicated that HL fragmentation occurs significantly faster in the gas phase in comparison to the literature rate of formation of major biofuel-phenolic compounds. In other words, the formation of phenolic compounds occurs at much lower rate constants being the limiting stage for lignin depolymerization. The critical role of surface associated reactions for …

The Math Mind Measures: A User Guide, H. Colleen Sinclair, Stacey R. Terrio, Youn Kyoung Kim

Reports

The development of the Math Mind Measures survey originated from a research-practitioner partnership (RPP) project funded by The Gates Foundation (namely the R+D Partnership for Math Equity). As a part of the project, our team wanted to understand what contributes to math motivation in students. Unfortunately, when looking for instruments to assess motivation we could find little consensus on which motivational factor(s) mattered most and how to measure them.

Long forms: Consequently, we integrated and strengthened existing measures – where available – of 10 different motivational variables, developing a pool of 138 items. We call this collection of items the …

Concomitant Entanglement And Control Criticality Driven By Collective Measurements, Thomas Iadecola, Justin H. Wilson, J. H. Pixley

Faculty Publications

Adaptive quantum circuits - where a quantum many-body state is controlled using measurements and conditional unitary operations - are a powerful paradigm for state preparation and quantum error-correction tasks. They can support two types of nonequilibrium quantum phase transitions: measurement-induced transitions between volume- and area-law-entangled steady states and control-induced transitions where the system falls into an absorbing state or, more generally, an orbit visiting several absorbing states. Within this context, nonlocal conditional operations can alter the critical properties of the two transitions and the topology of the phase diagram. Here, we consider the scenario where the measurements are nonlocal, in …

A Review Of Flood Mitigation Benefit-Cost Analyses’ Inclusiveness Of Environmental Watershed Effects And Environmental Vulnerability: Gaps In Progress Towards More Resilient Flood Hazard Decision-Making, Fahmida Akhter, Sapana Bastola, Jerrod Penn, Thomas Douthat

Faculty Publications

US and EU flood mitigation policy both incorporate considerations of costs and benefits, and in recent years have taken steps to encourage accounting for positive and negative effects on vulnerable populations, broader non-market environmental impacts, and downstream effects beyond the target area of projects of flood mitigation projects. This work highlights the extent to which previous academic flood mitigation Benefit-Cost Analyses (BCA) papers have comprehensively considered such project effects. We do so through a systematic, PRISMA-style, review of BCA literature in the broader field of flood hazard mitigation and resilience decision-making. Our results suggest 1) most projects focus on monetizing …

Challenges In Combating Climate Change: Lessons From Latin American And Caribbean Case Studies, Fabio Capra-Ribeiro

Faculty Publications

Climate change presents a complex global threat, particularly in Latin America and the Caribbean, where the impacts are severe, yet the region also showcases innovative approaches to face these issues. This study systematically analyzes the challenges faced by urban sustainability projects in the region, drawing insights from 35 case studies in the Urban Sustainability Exchange (USE) database. The primary objective is to identify shared challenges in implementing climate action initiatives, offering valuable lessons for future projects. Challenges were categorized into 14 themes, with issues related to collaboration and communication emerging as the most frequent. Other significant challenges included infrastructure limitations, …