Digital Commons Network^™

Synthesis And Characterization Of Bimetallic Plasmonic Nanoparticles Using Linear And Nonlinear Spectroscopy, Daniel Babayode

LSU Doctoral Dissertations

Recent exploration in the field of nanomaterials has led to the investigation of noble metal nanoparticles for various nanomedical applications. The spectroscopy of these nanoparticles is studied using both linear and nonlinear optical processes such as second harmonic generation (SHG), two-photon fluorescence (TPF), and extinction spectroscopy. Details pertaining to the growth dynamics of silver-gold core-shell (Ag@Au CS) nanoparticles (NPs) and gold-silver-gold core-shell-shell (Au@Ag@Au CSS) nanoparticles (NPs) are currently being investigated in order to obtain better control and optimization of the nanoparticle size and surface morphology. Transmission electron microscopy (TEM) images show that the nanoparticles have tunable core and shell sizes …

The Impact Of Outdoor Youth Education: An Examination Of The Social, Personal, And Environmental Developmental Outcomes Experienced By Youth At A Residential 4-H Summer Camp, Adam M. O'Malley

LSU Doctoral Dissertations

One of the most innovative ways that 4-H has fostered agricultural innovation and hands-on, experiential education has been through the development of youth outdoor education programs, more commonly known as 4-H Camp. State 4-H Camps and national camping events, including the inaugural National 4-H Conference, emerged following the establishment of localized county club camps. Three years after establishing the first 4-H Camp, more than 1,700 had emerged across the U.S., with early attendance exceeding 100,000 youth participants.

As a direct result of these early successes, the 4-H Camping movement has become celebrated as a novel technique to motivate youth to …

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 …

The Importance Of Fauna-Mediated Sediment O2 Consumption In The Ngom Hypoxic Zone, Hannah Beck, Kanchan Maiti

Faculty Publications

The northern Gulf of Mexico (NGOM) coastal shelf adjacent to the Mississippi and Atchafalaya rivers system experiences strong seasonal hypoxia in the late summer and coupled physical-biological models suggest that hypoxia formation in the NGOM is sensitive to benthic biogeochemical processes. However, the processes driving sediment oxygen consumption and their relationship to bottom oxygen concentration remain enigmatic. This study for the first time concurrently measured in situ total oxygen uptake (TOU) and diffusive oxygen uptake (DOU) during two different hypoxia seasons. The relatively large DOU: TOU ratio of 0.33 ± 0.07 observed during this study suggests more significant benthic infauna …

Indirect Effects And Context Dependency In Stream Fish Invasions, William K. Annis, Lily M. Thompson, Stephen R. Midway, Julian D. Olden, Brandon K. Peoples

Faculty Publications

Aim: Invasion ecology is replete with a body of well-supported yet contradictory evidence for numerous invasion hypotheses, likely as a result of context dependency. Context dependency in invasion studies can arise in two ways: (1) apparent, when results differ between studies solely due to methodical differences, or (2) mechanistic, when results truly differ due to ecological processes. One form of apparent context dependency occurs when causally linked factors associated with invasion success (hereafter, invasion drivers) either mask or enhance each other's effect on invasion success. Mechanistic context dependency can occur when regional scale processes modify the influence of local scale …

Future Climate Projections For Louisiana And Mississippi Using Wrf: Are Extreme Heat And Precipitation Events Intensifying?, Zuhayr S. Ishmam, Robert V. Rohli, Paul Miller

Faculty Publications

General circulation models (GCMs) lack the spatial resolution to capture the atmospheric and land-surface processes that shape regional climate. Regional climate models (RCMs) better resolve the interactions between large-scale weather patterns and local terrain. This study uses the Weather Research and Forecasting (WRF) model to perform high-resolution (12-km) dynamical downscaling for Louisiana and Mississippi over a historical (1996–2005) and a future (2090–2099) time span, forced by NCAR’s Community Earth System Model, version 1 (CESM1). Model performance was evaluated for the 1996–2005 period against atmospheric reanalysis and station observations, showing better skill for temperature than precipitation. Seasonal evaluation (winter: Dec-Feb; spring: …

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. …

Corrigendum: Diatom Transcriptional And Physiological Responses To Changes In Iron Bioavailability Across Ocean Provinces (Frontiers In Marine Science, (2017), 4, (360), 10.3389/Fmars.2017.00360), Natalie R. Cohen, Kelsey A. Ellis, Robert H. Lampe, Heather Mcnair, Benjamin S. Twining, Maria T. Maldonado, Mark A. Brzezinski, Fedor I. Kuzminov, Kimberlee Thamatrakoln, Claire P. Till, Kenneth W. Bruland, William G. Sunda, Sibel Bargu, Adrian Marchetti

Faculty Publications

In the published article, there was an error in Figure 3 as published. The initial (T0) phytoplankton community composition at site C2 was incorrectly displayed, with prasinophytes erroneously appearing as relatively abundant taxa. The corrected Figure 3 appears below. The average transcript proportions of phytoplankton taxa (outer charts) and diatom genera (inner charts) from initial seawater (T0) and during the first time point (T1; see Supplementary Table 1) within the Fe addition (Fe) and DFB addition (DFB) treatments at each site. Note that for site O5, the T2 control (Ctl) treatment is provided as the Fe-limited comparison. A text correction …

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 …

Petroleum Reservoir Dynamics, Mehdi Zeidouni

E-Textbooks

The book is structured into nine chapters, each designed to build a comprehensive understanding of reservoir engineering principles. Chapter 1 introduces the discipline and its connections with other areas of petroleum engineering. Chapters 2 through 5 address steady-state flow and its various complexities: Darcy’s equation and its limitations (Chapter 2); flow geometries and skin factor concepts (Chapter 3); compressible oil and gas flow (Chapter 4); and non-horizontal flow using the flow potential concept (Chapter 5).

In Chapter 6, the pressure diffusivity equation is explored alongside key concepts of radius of investigation and average reservoir pressure. Chapter 7 delves into the …

Machine Learning-Based Estimation Of Hoarseness Severity Using Acoustic Signals Recorded During High-Speed Videoendoscopy, Tobias Schraut, Michael Döllinger, Melda Kunduk, Matthias Echternach, Stephan Dürr, Julia Werz, Anne Schützenberger

Faculty Publications

Objectives: This study investigates the use of sustained phonations recorded during high-speed videoendoscopy (HSV) for machine learning-based assessment of hoarseness severity (H). The performance of this approach is compared with conventional recordings obtained during voice therapy to evaluate key differences and limitations of HSV-derived acoustic recordings. Methods: A database of 617 voice recordings with a duration of 250 ms was gathered during HSV examination (HS). Two databases comprising 809 vowels recorded during voice therapy were used for comparison, examining recording durations of 1 second (VT-1) and 250 ms (VT-2). A total of 490 features were extracted, including perturbation and noise …

History, Annotated Gazetteer, And Bibliography Of Ornithology In Kalimantan, Indonesian Borneo, Frederick H. Sheldon, Mohammad Irham, Daisy G. S. Kho, Erik Meijaard, Subir B. Shakya, Dewi M. Prawiradilaga, Sebastianus (Bas) Van Balen

Occasional Papers of the Museum of Natural Science, Louisiana State University

Kalimantan comprises nearly three quarters of the island of Borneo and is the place where scientific study of Bornean birds began. We describe the history of bird research in Kalimantan from its beginning, highlighting the ornithologists who explored the region and how their interests and methods changed over time, from a concentration on specimen collection, to examinations of community ecology, to conservation in the face of habitat change and species depletion, to the latest investigations using satellite, genetic, and digital technology. We also highlight some future directions for research, especially the need for more work on basic ecology and biogeography. …

Mini Worldlit: A Dataset Of Contemporary Fiction From 13 Countries, Nine Languages, And Five Continents, Andrew Piper, Mathias Iroro Orhero, David Bamman, Emrah Peksoy, Christina Han, Pallavi Rastogi, Jens Bjerring-Hansen, Sebastian Rasmussen, Hoyt Long, Roel Smeets, Itay Marienberg-Milikowsky, Alexandra Stuart, Tom Mcenaney, Mads Rosendahl Thomsen

Faculty Publications

World literature plays a key role in understanding the global diversity of human storytelling. However, datasets suitable for large-scale cross-cultural analysis remain limited. Responding to the increasing digitization of literary texts and the need for more diverse and multilingual resources, we introduce Mini Worldlit, a manually curated dataset of 1,192 works of contemporary fiction from 13 countries, representing nine languages across five continents. Mini Worldlit employs consistent cross-cultural selection criteria, overseen by scholarly experts, to ensure geographic, linguistic, and stylistic coherence. The dataset provides a foundation for future comparative studies of global literary cultures, offering a template for cross-cultural sampling. …

A Big Data Approach To Modelling Urban Population Density Functions: From Monocentricity To Polycentricity, Cehong Luo, Yujie Hu, Fahui Wang

Faculty Publications

Urban studies have a long tradition of examining the regularity of urban structure by modelling urban population density functions and probing the theoretical or behavioural foundation behind it. Previous studies commonly used census data in areal units such as census tracts or census block groups, which varied a great deal in area size and shape and led to the zonal and scale effects, commonly referred to as the modifiable areal unit problem (MAUP). This study uses big data of individual vehicle trips in Tampa, Florida, to define the precise population and employment distribution locations, and then aggregates them with uniform …

Can Americans’ Trust In Local News Be Trusted? The Emergence, Sources, And Implications Of The Local News Trust Advantage, Erik Peterson, Joshua P. Darr, Maxwell B. Allamong, Michael Henderson

Faculty Publications

Despite eroding consensus about credible political news sources, much of the public still trusts local media. We assess the emergence, sources, and implications of the trust advantage local news holds over national media. We argue the public now uses a news outlet's local orientation as a shortcut to assess its credibility. In survey experiments, we find unfamiliar news outlets are trusted more when they have a local cue in their name. In surveys where people evaluate digital sources covering their community, this heuristic leads the public to trust unreliable information providers that signal a local focus more than high-quality sources …

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 …

Fgf21 Acts In The Brain To Drive Macronutrient-Specific Changes In Behavioral Motivation And Brain Reward Signaling, Md Shahjalal H. Khan, Sora Q. Kim, Robert C. Ross, Florina Corpodean, Redin A. Spann, Diana A. Albarado, Sun O. Fernandez-Kim, Blaise Clarke, Hans Rudolf Berthoud, Heike Münzberg, David H. Mcdougal, Yanlin He, Sangho Yu, Vance L. Albaugh, Paul L. Soto, Christopher D. Morrison

Faculty Publications

Objective: Dietary protein restriction induces adaptive changes in food preference, increasing protein consumption over carbohydrates or fat. We investigated whether motivation and reward signaling underpin these preferences. Methods and Results: In an operant task, protein-restricted male mice responded more for liquid protein rewards, but not carbohydrate, fat, or sweet rewards compared to non-restricted mice. When the number of responses required to access protein reward varied, protein-restricted mice exhibited higher operant responses at moderate to high response requirements. The protein restriction-induced increase in operant responding for protein was absent in Fgf21-KO mice and mice with neuron-specific deletion of the FGF21 co-receptor …

Is Verbal Rehearsal Strategic? An Investigation Into Overt Rehearsal Of Nameable Pictures In 5- To 10-Year-Old Children, Candice C. Morey, Angela M. Aubuchon, Meg Attwood, Thomas Castelain, Nelson Cowan, Davide Crepaldi, Emilie Fjerdingstad, Eivor Fredriksen, Chris Jarrold, Chris Koch, Jaroslaw R. Lelonkiewicz, Gary Lupyan, Whitney Mendenhall, David Moreau, Christina Schonberg, Christian K. Tamnes, Haley Vlach, Emily M. Elliott

Faculty Publications

Though verbal rehearsal is a frequently endorsed strategy for remembering short lists among adults, there is ambiguity around when children deploy it, and what circumstantial factors encourage them to rehearse. We recoded data from a recent multilab replication of a serial picture memory task in which children were observed for evidence of task-related speech or lip movements to extract finer-grained detail about how children spoke during the task. With these data, we aimed to better understand the manner in which children rehearse and the task scenarios which elicit overt rehearsal. Children in several countries from 5 to 10 years old …

Beyond Reoffending And Rearrest: Expanding The Collateral Consequences Of Formal Processing To Youth Homelessness, Natasha Chlebuch, Jennifer Paruk, Caitlin Cavanagh, Paul J. Frick, Laurence Steinberg, Elizabeth Cauffman

Faculty Publications

There is robust evidence that juvenile justice contact during formative years is associated with deleterious outcomes. The effect of juvenile court intervention on youth homelessness, however, has received scant empirical attention despite evidence that many justice-involved youth are represented in the unhoused youth and adult population. This study leverages data collected from the Crossroads Study (N = 1115), a longitudinal, multi-site study to explore the impact of formal processing on subsequent experiences with homelessness. This study found that even when accounting for the effect of detention and other factors associated with youth homelessness, youth who were formally processed were twice …

Alternative Theories Of Covid-19: Social Dimensions And Information Sources, Wesley Shrum, Paige Miller, Nana Osei Asiamah, Fangyue Zou

Faculty Publications

While scientific understanding of the COVID-19 pandemic increased, conspiracy theories undermined the foundations of public health policy, making it significantly more difficult both to discuss and to implement. Popular alternative narratives include the claim that government was using restrictions to control people's behavior, and that the pandemic was caused by 5G cellular technology. We examine the extent to which alternative beliefs were associated with sociodemographic characteristics and the sources through which people acquired information during the pandemic. Our analysis uses a demographically balanced online survey of 10,022 participants from 50 US states, collected during August of 2021. Results indicate that …

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 …

Complex Models Of Sequence Evolution Improve Fit, But Not Gene Tree Discordance, For Tetrapod Mitogenomes, Benjamin S. Toups, Robert C. Thomson, Jeremy M. Brown

Faculty Publications

Variation in gene tree estimates is widely observed in empirical phylogenomic data and is often assumed to be the result of biological processes. However, a recent study using tetrapod mitochondrial genomes to control for biological sources of variation due to their haploid, uniparentally inherited, and non-recombining nature found that levels of discordance among mitochondrial gene trees were comparable to those found in studies that assume only biological sources of variation. Additionally, they found that several of the models of sequence evolution chosen to infer gene trees were doing an inadequate job of fitting the sequence data. These results indicated that …

How Do Active Duty Army Personnel View The Relationships Between Firearms And Suicide? The Role Of Sociopsychological Factors, Firearm Ownership Status, And Lifetime History Of Suicidal Thoughts And Behaviors, Samantha E. Daruwala, Nicholas Allan, Raymond Tucker, Craig J. Bryan, Michael N. Dretsch, Benjamin Trachik, Melanie L. Bozzay

Faculty Publications

Background: Firearms are the primary method by which US military personnel die by suicide, and those at highest risk tend to store firearms unsafely. Promoting secure firearm storage practices is a major component of the Department of Defense’s suicide prevention strategy, but perceptions about firearms being associated with suicide risk may impact such efforts. Purpose: This study examined perceptions that (1) firearm ownership and (2) storage practices are associated with suicide risk and whether key sociopsychological factors (e.g., entrapment, threat perceptions, honor ideology) were associated with these beliefs in a sample of Active Duty (AD) enlisted Army personnel. We then …

Academic Screening In Middle School: Exploring Bivariate And Intraindividual Relations In Reading And Math Performance, Kelly N. Clark, Garret J. Hall

Faculty Publications

Early adolescence is a pivotal time for academic development; however, the vast majority of research on reading and math development within a multitiered system of support has been conducted among elementary students. Using triannual (Fall, Winter, Spring) academic screening data, we examined the transactional development of reading and math skills among sixth and seventh grade students (N = 1,693) using Bayesian longitudinal structural equation modeling (SEM). We find equivocal support for four of the five types of longitudinal SEMs tested (dual-change, linear change, proportional change, latent curve with structured residuals, and random-intercepts cross-lagged models). Stable between-person differences in math and …

American Civil Wars: A Continental History, Andre Fleche

Civil War Book Review

No abstract provided.

The Civil War In The Age Of Nationalism, William "Winn" Carroll

Civil War Book Review

No abstract provided.

Millenarian Dreams And Racial Nightmares: The American Civil War As An Apocalyptic Conflict, Adam J. Krejčí

Civil War Book Review

No abstract provided.