Digital Commons Network^™

Engineering Inlet Structures To Enhance Dna Capture Into Nanochannels In A Polymer Nanofluidic Device Produced Via Nanoimprint Lithography, Jiahao Wu, Junseo Choi, Franklin I. Uba, Steven A. Soper, Sunggook Park

Faculty Publications

Operating nanofluidic biosensors requires threading single molecules to be analyzed from microfluidic networks into nanostructures, mostly nanochannels or nanopores. Different inlet structures have been employed as a means of enhancing the number of the capture events into nanostructures. Here, we systematically investigated the effects of various engineered inlet structures formed at the micro/nanochannel interface on the capture of single λ-DNA molecules into the nanochannels. Different inlet geometries were evaluated and ranked in order of their effectiveness. Adding an inlet structure prior to a nanochannel effectively improved the DNA capture rate by 190–700% relative to that for the abrupt micro/nanochannel interface. …

Breaking Boundaries In Wind Engineering: Lsu Wise Open-Jet Facility Revolutionizes Solar Panel And Building Design, Aly Mousaad Aly

Faculty Publications

Featured Application: The Louisiana State University (LSU) Windstorm Impact, Science, and Engineering (WISE) Open-Jet Testing facility is instrumental in enhancing structural resilience under windstorms. The facility represents a Mid-Scale Research Infrastructure to address grand challenges and the need for experimental capabilities in the mid-scale range. Its unique capabilities enable the comprehensive testing and evaluation of critical infrastructure components, encompassing low- and high-rise buildings, photovoltaic (PV) solar panels, wind turbines, bridges, vegetation (nature-based solutions), power transmission lines, and more. Through controlled wind conditions, researchers can gain invaluable insights into the behaviour and performance of these critical infrastructures. The facility is pivotal …

Experimental Evaluation Of Asphalt Mixtures With Emerging Additives Against Cracking And Moisture Damage, Md Tanvir A. Sarkar, Mostafa A. Elseifi

Faculty Publications

The objective of this study was to evaluate and recommend an asphalt mixture design with emerging additive technologies that would provide superior performance against asphalt concrete (AC) stripping and cracking. To achieve this objective, a laboratory test program was developed to evaluate the use of nanomaterials (nanoclay and graphene nanoplatelet), an emerging anti-stripping agent (adhere), and warm-mix asphalt technologies (ZycoTherm, Sasobit, and EvoTherm). Two mix types were evaluated, which were a stone-matrix asphalt (SMA) and a dense-graded binder mix. In addition, the modified Lottman test (AASHTO T 283) and the indirect tensile asphalt cracking test (IDEAL-CT) test were used as …

Crystal–Melt Interfaces In Mg2sio4 At High Pressure: Structural And Energetics Insights From First-Principles Simulations, Bijaya B. Karki, Dipta B. Ghosh, Jianwei Wang, Shun Ichiro Karato

Faculty Publications

The interplay between crystal–melt and grain boundary interfaces in partially melted polycrystalline aggregates controls many physical properties of mantle rocks. To understand this process at the fundamental level requires improved knowledge about the interfacial structures and energetics. Here, we report the results of first-principles molecular dynamics simulations of two grain boundaries of (0l1)/[100] type for tilt angles of 30.4° and 49.6° and the corresponding solid–liquid interfaces in Mg2SiO4 forsterite at the conditions of the upper mantle. Our analysis of the simulated position time series shows that structural distortions at the solid–liquid interfacial region are stronger than intergranular interfacial distortions. The …

Do Contributing Files Provide Information About Oss Newcomers' Onboarding Barriers?, Felipe Fronchetti, David C. Shepherd, Igor Wiese, Christoph Treude, Marco Aurélio Gerosa, Igor Steinmacher

Faculty Publications

Effectively onboarding newcomers is essential for the success of open source projects. These projects often provide onboarding guidelines in their 'CONTRIBUTING' files (e.g., CONTRIBUTING.md on GitHub). These files explain, for example, how to find open tasks, implement solutions, and submit code for review. However, these files often do not follow a standard structure, can be too large, and miss barriers commonly found by newcomers. In this paper, we propose an automated approach to parse these CONTRIBUTING files and assess how they address onboarding barriers. We manually classified a sample of files according to a model of onboarding barriers from the …

Performative Mixing For Immersive Audio, Brian A. Elizondo

LSU Doctoral Dissertations

Immersive multichannel audio can be produced with specialized setups of loudspeakers, often surrounding the audience. These setups can feature as few as four loudspeakers or more than 300. Performative mixing in these environments requires a bespoke solution offering intuitive gestural control. Beyond the usual faders for gain control, advancements in multichannel sound demand interfaces capable of quickly positioning sounds between channels. The Quad Cartesian Positioner is such a solution in the form of a Eurorack module for surround mixing for use in live or studio performances.

Diffusion/mixing methods for live multichannel immersive music often rely on the repurposing of hardware …

An Intersection Of Science & Art: Vitrification Approaches And Open-Fabricated Tools For The Biomedical Model Sea Hare, Aplysia Californica, Allyssa M. Oune

LSU Master's Theses

The California sea hare (Aplysia californica) is an important biomedical model for molecular neurobiology, electrophysiology, learning, and memory due to their well-mapped and large neurons and well-characterized learning capabilities. The National Resource for Aplysia (NRA, University of Miami) maintains large stocks of live animals and relies on regular shipments of wild-caught individuals to maintain genetic diversity. This is labor and cost-intensive, and environmental changes could alter the availability of wild animals increasing the need to preserve this genetic resource. One solution is vitrification, ultra-fast cooling which produces an amorphous glass that minimizes damage to cells. Aplysia californica presents …

Improving Cellphone-Based Bio-Imaging Technique For Fluorescence Detection, Erteza T. Efaz

LSU Master's Theses

The research presented in this thesis focuses on the design, development, and evaluation of a fluorescence detection system. The system is implemented primarily as an Android application, Auto Camera, which leverages smartphone cameras to capture and analyze fluorescent images. The application provides a user-friendly interface with some configurable features like exposure time, ISO speed, and storage limit; as well as defining detection thresholds and setting acquisition intervals. This study begins with the architectural framework of the Android application, which is written in Java using Android Studio. The API compatibility is set to version 33, and users are prompted to grant …

Surrogate-Assisted Simulation-Optimization Framework For Groundwater Management In A Multi-Aquifer System, Melika Mani

LSU Master's Theses

Uncontrolled groundwater exploitation can lead to aquifer depletion, land subsidence, and saltwater intrusion. Effective groundwater management is challenging due to the intricate nature of subsurface hydrogeology and spatiotemporally variable pumping, especially in a multi-aquifer system. To ensure sustainable withdrawal, multi-objective optimization is an effective tool for balancing management goals and drawdown effects. However, running simulation-optimization using detailed groundwater models is computationally expensive, pushing decision-makers to decide based on limited scenarios. In this study, a hydrogeological framework was constructed for the Capital Area, Louisiana, allowing for individual assessment of each unit to better understand each aquifer's condition. Moreover, a surrogate-assisted simulation-optimization …

Dry Reforming Of Methane Over Substituted Lanthanum Zirconate Pyrochlore Catalysts, Srikar Bhattar

LSU Doctoral Dissertations

One of the potential methods for producing syngas from two greenhouse gases (CH₄ and CO₂) is dry reforming of methane (DRM), which has received a lot of attention. DRM could lower the net emission of these gases if the energy used to power it comes from sources other than hydrocarbons. Despite being highly active, many conventional Ni based metal/support catalyst systems rapidly lose their activity due to the sintering or deposition of coke on the metal clusters' surfaces. Thus, it is crucial that the DRM catalyst must be coke resistant and thermally stable to avoid sintering.

DRM …

Development Of Novel Biosensors For Direct Measurement Of Proteasome Activity In Intact Single Cells, Alireza Rahnama

LSU Doctoral Dissertations

Enzymes regulate nearly all cellular and biochemical processes governing cellular proliferation, metabolism, and migration. One example is the ubiquitin-proteasome system (UPS), a highly complex, tightly regulated pathway responsible for the recognition and degradation of misfolded or damaged proteins inside the cell. Protein degradation requires posttranslational addition of a polyubiquitin chain to target the protein to the proteasome for degradation which can be reversed by deubiquitinating enzymes (DUBs) which remove the chain. Dysregulation of the UPS is associated with many diseases including cancer which has resulted in the development of inhibitors, like Bortezomib and Carfilzomib, driving higher median patient survival rates …

Ml-Empowered Nondestructive Evaluation In Additive Manufacturing, Mohammadsaber Nemati

LSU Doctoral Dissertations

This dissertation investigates cutting-edge AI-based approaches to enhance Nondestructive Evaluation in Additive Manufacturing (AM). As a larger workflow that aims to design complex alloys and shape memory polymers for AM, this effort tries to leverage machine learning to achieve performance and structural integrity goals in the material characterization stage. The dissertation comprises three key test cases:

1. X-ray CT Data Analysis Using Machine Learning

This section identifies the limitations of manual pixel-level segmentation in X-ray CT data analysis and introduces zero-shot learning. A self-supervised approach is proposed, eliminating manual segmentation and enhancing crack detection and prediction.

2. Neutron Imaging of …

Carbonate Precipitation Behavior In Co2 Mea Electrolyzers With Cu Electrocatalyst, John C. Hendershot

LSU Master's Theses

Annually, over 35 billion metric tons of carbon dioxide (CO₂) are emitted into Earth’s atmosphere. The accumulated CO₂ emissions in the atmosphere over the last century drive climate change. CO₂ electroreduction (CO₂ER) is an emerging technology that aims to recycle carbon emissions from the industrial sector by using CO₂, H₂O, and electricity as a feedstock to produce ethylene (C₂H₄) at current densities as high as 1 A cm^-2 and Faradaic efficiencies (FE) of 60%. However, CO₂ electrolyzers currently demonstrate poor durability at industrially relevant …

Induction Heating Driven Heterogeneous Catalysis: Magnetically Induced Nanoparticle Catalysts, Cameron Lee Roman

LSU Doctoral Dissertations

Heterogeneous catalysis has been and continues to be highly studied due to being one of the cornerstones of the chemical industry. With an increasing demand for chemicals and rising costs, there is a growing need to adapt to changing feed stocks and increase production efficiency. Polymers, oxygenates, and other chemical intermediates are predicted to experience continued growth, corresponding to an increased need for olefines. Due to the abundance of shale gas, researchers and producers are interested in meeting this demand via the dehydrogenation of light alkanes.

While dehydrogenation catalysts are a valuable tool in olefin production, selectivity and deactivation remain …

Understanding And Modeling Drivers’ En-Route Diversion Behavior During Congestion, Mohammad Shapouri

LSU Doctoral Dissertations

In the field of transportation, traffic assignment models primarily have been used to forecast driver route preferences, translating their choices into traffic flow patterns across networks. These models are grounded in distinct behavioral theories and strive to explain how drivers navigate routes based on network features and personal tendencies. Using an aggregation approach, conventional traffic assignment models distribute demand among paths, considering utility and attractiveness. Despite their prevalent use in transportation planning and operations, the fundamental behavioral assumptions of these models have rarely been thoroughly explored. This gap is further compounded by their limited consideration of real-time adjustments and choices …

Modeling Multi-Grained User Preference In Location Visitation, Yingrong Qin, Chen Gao, Zhen Tu, Hongsheng Wu, Shuangqing Wei, Yue Wang, Lin Zhang, Yong Li

Faculty Publications

Location prediction acts as a fundamental service in today's location-based information platform, which helps users access locations satisfying their demands, improving both user experience and platform profit. Since users with unambiguous demands prefer specific locations while users with compound demands consider first regions and then specific locations, it is necessary to model multi-grained user preferences at different geographical scales. However, most of the existing works concentrate on user preferences at the location-scale only, which can not understand users traveling behaviors thoroughly. In this paper, we propose to model both the fine-grained user preferences at the location scale and the coarsegrained …

The Structures And Functions Of Offices Of Academic Affairs: A Case Study, Ryan Thomas Landry

LSU Doctoral Dissertations

This study sought to describe how offices of academic affairs (administrative offices supporting provosts) at public, research-intensive universities in the United States are structured and what kind of work these offices do. There is a dearth of scholarly literature on the topic, indicative of an overall lack of knowledge about these organizations. From a practical standpoint, I intended for this study to contribute to the body of knowledge of higher education administration with hopes that it provides helpful insights to administrators as they consider organizational design. Using the theoretical framework of modern organization theory, I employed an embedded case study …

Evaluating Hpx And Kokkos On Risc-V Using An Astrophysics Application Octo-Tiger, Patrick Diehl, Gregor Daiss, Steven Brandt, Alireza Kheirkhahan, Hartmut Kaiser, Christopher Taylor, John Leidel

Faculty Publications

In recent years, computers based on the RISC-V architecture have raised broad interest in the high-performance computing (HPC) community. As the RISC-V community develops the core instruction set architecture (ISA) along with ISA extensions, the HPC community has been actively ensuring HPC applications and environments [10, 29] are supported. In this context, assessing the performance of asynchronous many-task runtime systems (AMT) is essential. In this paper, we describe our experience with porting of a full 3D adaptive mesh-refinement, multi-scale, multi-model, and multi-physics application, Octo-Tiger, that is based on the HPX AMT, and we explore its performance characteristics on different RISC-V …

Translation Speed Influence On Tropical Cyclone Storm Tide And Surge Generation Along The Gulf Of Mexico Coast, Samantha L. Camarda

LSU Master's Theses

This research examines tropical cyclone translation speed as a factor in storm tide and surge height upon landfall on the United States Gulf Coast. Understanding the effect of translation speed on peak storm tide/surge height is needed to better prepare for and predict future damage from tropical cyclone events. Tropical cyclone data are taken from hourly interpolated best-track HURDAT2 data from 1970–2021. This study uses the HURDAT2 hourly interpolated observation data points (24-hours) pre-landfall to landfall. Translation speed is calculated based on the distance traversed between hourly points. Peak storm tide and storm surge data are taken from SURGEDAT from …

Top Ten Priorities For Global Saltmarsh Restoration, Conservation And Ecosystem Service Research, Julien Pétillon, Emma Mckinley, Meghan Alexander, Janine B. Adams, Christine Angelini, Thorsten Balke, John N. Griffin, Tjeerd Bouma, Sally Hacker, Qiang He, Marc J.S. Hensel, Carles Ibáñez, Peter I. Macreadie, Simone Martino, Elwyn Sharps, Rhoda Ballinger, Davide De Battisti, Nicola Beaumont, Daryl Burdon, Pedro Daleo, Andrea D'Alpaos, Mollie Duggan-Edwards, Angus Garbutt, Stuart Jenkins, Cai J.T. Ladd, Heather Lewis, Giulio Mariotti, Osgur Mcdermott, Rachael Mills, Iris Möller, Stefanie Nolte, Jordi F. Pagès, Brian Silliman

Faculty Publications

Coastal saltmarshes provide globally important ecosystem services including ‘blue carbon’ sequestration, flood protection, pollutant remediation, habitat provision and cultural value. Large portions of marshes have been lost or fragmented as a result of land reclamation, embankment construction, and pollution. Sea level rise threatens marsh survival by blocking landward migration where coastlines have been developed. Research-informed saltmarsh conservation and restoration efforts are helping to prevent further loss, yet significant knowledge gaps remain. Using a mixed methods approach, this paper identifies ten research priorities through an online questionnaire and a residential workshop attended by an international, multi-disciplinary network of 35 saltmarsh experts …

Efficient Chemical-Free Degradation Of Waterborne Micropollutants With An Immobilized Dual-Porous Tio2 Photocatalyst, Daniel E. Willis, Ella C. Sheets, Mary R. Worbington, Madhusudan Kamat, Sarah K. Glass, Ma Cayla J. Caso, Tochukwu Ofoegbuna, Liz M. Diaz, Caleb Osei-Appau, Samuel D. Snow, Kevin M. Mcpeak

Faculty Publications

Photocatalytic advanced oxidation processes (AOPs) promise a chemical-free route to energy-efficient degradation of waterborne micropollutants if long-standing mass transfer and light management issues can be overcome. Herein, we developed a dual-porous photocatalytic system consisting of a mesoporous (i.e., 2-50 nm pores) TiO2 (P25) photocatalyst supported on macroporous (i.e., >50 nm pores) fused quartz fibers (P25/QF). Our reusable photocatalytic AOP reduces chemical consumption and exhibits excellent energy efficiency, demonstrated by degrading various pharmaceutical compounds (acetaminophen, sulfamethoxazole, and carbamazepine) in natural waters with electrical energy per order (EEO) values of 4.07, 0.96, and 1.35 kWh/m3, respectively. Compared to the conventional H2O2/UVC AOP, …

Using Machine Learning To Measure Changes In Immunity Due To Climate Change In The Fall Armyworm, Spodoptera Frugiperda, Nathaniel T. Haulk

LSU Master's Theses

Object detection is a recent development that allows for the detection of multiple objects in photographs. Numerous machine learning algorithms have been developed for object detection. Here we sought to determine which algorithm performed best when relating to an organism's health and immunological response. The fall armyworm (Spodoptera frugiperda) is a major agricultural pest causing millions of dollars in damage to farmlands across the globe. With their recent spread into Africa and Asia, the need for understanding how best to control population outbreaks via biocontrol has increased. While viruses are a major biocontrol agent for controlling insect pests, we …

Evaluating Attack Surface Management In An Industrial Control System (Ics) Environment: Leveraging A Recon Ftw For Threat Classification And Incident Response, Nathalia De Sa Soares

LSU Master's Theses

Protecting Industrial Control Systems (ICS) from cyber threats is paramount to
ensure the reliability and security of critical infrastructure. Organizations must proactively identify vulnerabilities and strengthen their incident response capabilities as attack vectors evolve. This research explores implementing an Attack Surface Management (ASM) approach, utilizing Recon FTW, to assess an operating ICS environment’s security posture comprehensively.
The primary objective of this research is to develop a tool for performing recon-
naissance in an ICS environment with a non-intrusive approach, enabling the realistic simulation of potential threat scenarios and the identification of critical areas requiring immediate attention and remediation. We aim …

Exploring Older Adults' Mobility Challenges And Preferences Before And After Covid-19 Pandemic, Bernard Boakye

LSU Master's Theses

Seniors (65 years and above) are most disadvantaged with their mobility due to their declining health and limited travel options, especially after retiring from driving. They have been the most affected age group during the COVID-19 because of their weak immune systems. This study aimed to investigate the transportation mobility preferences and challenges of seniors and their willingness to use Autonomous Vehicles (AVs) before and during COVID-19.

Using a national survey, responses from 1507 senior Americans from the 50 U.S. states were gathered proportionally to reflect the senior population by age, gender, race, and state. A McNemar-Bowker Chi-Square test was …

Development, Implementation, And Evaluation Of Swirl-Combustion Strategies For Optimal Performance Of Ammonia As A Fuel For Gas Turbine Engines, Varun Nanjunda Rao Viswamithra

LSU Doctoral Dissertations

In an effort to reduce harmful effects of greenhouse gas emissions, ammonia is being pursued as a fuel for power generation as it is a carbon-free energy source. However, the use of ammonia-air mixtures in premixed swirl combustors poses challenges due to low flame speed and reactivity resulting in combustor stability issues in addition to high Nitrous Oxide (NOx) emissions due to the presence of fuel-bound Nitrogen. The first part of this study attempts to overcome lean blowout limits of methane-ammonia-air mixtures using a novel, multi-point () injection strategy, whereby micron-sized holes on the swirler vanes generate a co-flowing stream …

The Future Of Cyanobacteria Toxicity In Estuaries Undergoing Pulsed Nutrient Inputs: A Case Study From Coastal Louisiana, Sibel Bargu, Matthew Hiatt, Kanchan Maiti, Paul Miller, John R. White

Faculty Publications

Harmful cyanobacteria blooms (cyanoHABs) are a global phenomenon, especially in calm, warm, and nutrient-rich freshwater and estuarine systems. These blooms can produce various potent toxins responsible for animal poisoning and human health problems. Nutrient-rich freshwater pulsed into estuaries affects turbidity, water temperature, salinity, and nutrient concentrations and ratios at irregular intervals, creating a highly dynamic habitat. However, the underlying processes that lead to the selective development of cyanoHABs for certain species and the fate of their toxins are still uncertain. This paper draws upon the rich body of research available for one such system, the Lake Pontchartrain Estuary, Louisiana, to …

Politics In Applicant Attraction And Recruitment: Firm Response To Abortion Legislation And Its Impact On Applicant Interest, Madeleine Coward

Honors Capstones

No abstract provided.

Limnological Response Of Las Curias Reservoir, San Juan, Puerto Rico: Successful Management Of The Invasive Aquatic Fern, Salvinia Molesta, Xavier A. García-López, Jorge R. Ortiz-Zayas, Rodrigo Díaz, Aurelio Castro-Jiménez, Charles F. Wahl

Faculty Publications

The anthropogenic deterioration of aquatic ecosystems affects water resources due to agricultural malpractices, pollution from domestic septic tanks, recreational activities, and poor watershed management, among other factors. This study examines the management of Las Curias Reservoir, San Juan, Puerto Rico, after the 2016 arrival of the invasive aquatic fern Salvinia molesta. In September 2019, a community-led initiative introduced the Cyrtobagous salviniae weevil, an effective biological control agent for S. molesta, and commenced a mechanical removal campaign using an aquatic harvester. Limnological sampling (September 2019 to September 2022) and drone flights were employed to measure physicochemical and floating plant cover changes, …

Community-Wide Correlations Between Species Richness, Abundance And Population Genomic Diversity In A Freshwater Biodiversity Hotspot, Jamie R. Bucholz, Garrett W. Hopper, Irene Sánchez González, Taylor E. Kelley, Colin R. Jackson, Ryan C. Garrick, Carla L. Atkinson, Jeffrey D. Lozier

Faculty Publications

Understanding patterns of diversity across macro (e.g. species-level) and micro (e.g. molecular-level) scales can shed light on community function and stability by elucidating the abiotic and biotic drivers of diversity within ecological communities. We examined the relationships among taxonomic and genetic metrics of diversity in freshwater mussels (Bivalvia: Unionidae), an ecologically important and species-rich group in the southeastern United States. Using quantitative community surveys and reduced-representation genome sequencing across 22 sites in seven rivers and two river basins, we surveyed 68 mussel species and sequenced 23 of these species to characterize intrapopulation genetic variation. We tested for the presence of …

Validity Of An Artificial Intelligence-Based Application To Identify Foods And Estimate Energy Intake Among Adults: A Pilot Study, Chloe P. Lozano, Emma N. Canty, Sanjoy Saha, Stephanie T. Broyles, Robbie A. Beyl, John W. Apolzan, Corby K. Martin

Clinical Research Faculty Publications

Background: The commercial application Openfit allows for automatic identification and quantification of food intake through short video capture without a physical reference marker. There are no known peer-reviewed publications on the validity of this Nutrition Artificial Intelligence (AI). Objectives: To test the validity of Openfit to identify food automatically and semiautomatically (with user correction), test the validity of Openfit at quantifying energy intake (kcal) automatically and semiautomatically, and assess satisfaction and usability of Openfit. Methods: During a laboratory-based visit, adults (7 male and 17 female), used Openfit to automatically and semiautomatically record provided meals, which were covertly weighed. Foods logged …