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The Bridal Industry: Body Image And Sizing Charts, Natalie Knapp Aug 2023

The Bridal Industry: Body Image And Sizing Charts, Natalie Knapp

Apparel Merchandising and Product Development Undergraduate Honors Theses

The apparel industry in the United States of America lacks a unified size chart. This inconsistency allows vanity sizing and individual retailers to preside over the systematic regulations of sizing. The bridal industry is the singular industry that is not affected by vanity sizing in the United States, which causes a plethora of issues when coupled with the media’s thin ideal and push of certain body standards.

The project utilized four sections of literature review: regarding sizing inconsistency, mass media and size dysphoria, United States standard of sizing, and brides and weight loss. Additionally, four different size charts from four …


Social And Economic Changes In A Mid-Size University City: The Case Of South Fayetteville, Arkansas, Korab Vranovci Aug 2023

Social And Economic Changes In A Mid-Size University City: The Case Of South Fayetteville, Arkansas, Korab Vranovci

Graduate Theses and Dissertations

The constant growth of the city of Fayetteville is attributed to regional economic growth and an increase in student enrollment, to name a few. As a middle-sized college city, Fayetteville is an anchor city with the University of Arkansas as its anchor institution. These changes have caused a significant increase in the city's urban development and neighborhood changes. This research identifies three areas of work with the potential to assist in the study of the urban redevelopment in the South Fayetteville neighborhoods: (1) the social demographics, economic, and land use changes in neighborhood populations, (2) the stakeholder's perceptions toward city …


Poly(Ionic Liquid)S For Magnetic, Ionic, And Electrical Stimuli-Responsive Applications, Kayla Ann Foley Aug 2023

Poly(Ionic Liquid)S For Magnetic, Ionic, And Electrical Stimuli-Responsive Applications, Kayla Ann Foley

Graduate Theses and Dissertations

Poly(ionic liquid)s (PILs) are a fascinating subclass of strong polyelectrolytes formed from polymerizable ionic liquids. As a result of their unique properties and counterion exchangeability, PILs can exhibit conformation structure or material property changes in response to external stimuli such as changes in pH/ionic environment, magnetic fields, and electric potentials. In Chapter 1, a comprehensive review of PILs design as well as their stimuli-responsive behavior is provided. Additional motivation for each dissertation chapter is also discussed. In Chapter 2, magnetically responsive PILs (MPILs) are developed from complexing paramagnetic salts with a random PIL copolymer containing a metal-coordinating co-monomer, acrylamide. A …


Next-Generation Nanopore Sensors Based On Conductive Pulse Sensing For Enhanced Detection Of Nanoparticles, Samuel Confederat, Seungheon Lee, Derr Vang, Dimitrios Soulias, Fabio Marcuccio, Timotheus I. Peace, Martin Andrew Edwards, Pietro Strobbia, Devleena Samanta, Christoph Wälti, Paolo Actis Aug 2023

Next-Generation Nanopore Sensors Based On Conductive Pulse Sensing For Enhanced Detection Of Nanoparticles, Samuel Confederat, Seungheon Lee, Derr Vang, Dimitrios Soulias, Fabio Marcuccio, Timotheus I. Peace, Martin Andrew Edwards, Pietro Strobbia, Devleena Samanta, Christoph Wälti, Paolo Actis

Chemistry & Biochemistry Faculty Publications and Presentations

Nanopore sensing has been successfully used to characterize biological molecules with single-molecule resolution based on the resistive pulse sensing approach. However, its use in nanoparticle characterization has been constrained by the need to tailor the nanopore aperture size to the size of the analyte, precluding the analysis of heterogeneous samples. Additionally, nanopore sensors often require the use of high salt concentrations to improve the signal-to-noise ratio, which further limits their ability to study a wide range of nanoparticles that are unstable at high ionic strength. Here, a new paradigm in nanopore research that takes advantage of a polymer electrolyte system …


Risk-Returns Of Forward Contracting Southern Row Crops With Crop Revenue Insurance, Chandan Bhattarai Aug 2023

Risk-Returns Of Forward Contracting Southern Row Crops With Crop Revenue Insurance, Chandan Bhattarai

Graduate Theses and Dissertations

This study evaluated the risk and return associated with various levels of forward contracting for southern row crops, specifically corn, soybean, and rice, in conjunction with different coverage levels of the Revenue Protection (RP) crop insurance program and government support plans. Forward contracting is a strategy to manage price risk by transferring ownership of physical grain from a seller to a buyer at a pre-agreed time. RP is a return-based crop insurance program offering coverage levels ranging from 50-85 percent in 5 percent increments, which allows producers to hedge against yield or price risks. Additionally, the study analyzed the effectiveness …


Characterizing Logistics Operations Within A Federal Staging Area For Hurricane Response: A Qualitative Analysis Of Federal, State And Local Perspectives, Jannatul Shefa Aug 2023

Characterizing Logistics Operations Within A Federal Staging Area For Hurricane Response: A Qualitative Analysis Of Federal, State And Local Perspectives, Jannatul Shefa

Graduate Theses and Dissertations

A successful deployment of logistics operations following a disaster is a collective contribution of federal, state, and local entities to ascertain an efficient and effective response. This research analyzes data from interviews with disaster response logistics experts from these entities. The objective is to investigate the information sources and planning processes used in these organizations to plan vehicle routes for critical resource deliveries to impacted areas. Special attention is directed to the impacts of incomplete knowledge of infrastructure status, such as road disruptions due to debris or flooding. Supported by both qualitative and quantitative evidence, the study finds that incomplete …


Comparing Predictive Performance Of Garch And Stochastic Volatility Models, Swapnaneel Nath Aug 2023

Comparing Predictive Performance Of Garch And Stochastic Volatility Models, Swapnaneel Nath

Graduate Theses and Dissertations

This paper compares the predictive performance of two commonly used financial models, the Generalized Auto-Regressive Conditional Heteroskedasticity (GARCH) model, and the Stochastic Volatility model. Both techniques are used in the finance literature to model returns on an asset; the main difference between the two is that the former holds volatility as deterministic, whereas the latter treats it as a stochastic component. Three 10-year periods (2006-15, 2008-17, and 2010-19) of returns of the S&P-500 Index are used to train the two models. The parameter estimation is done using Hamiltonian Monte Carlo. Then, using Sequential Monte Carlo updates, returns for 2016, 2018, …


Dietary Histidine: Broiler Responsiveness With And Without Endogenous Histidine Reserve Consideration, Kenneth Blake Nelson Aug 2023

Dietary Histidine: Broiler Responsiveness With And Without Endogenous Histidine Reserve Consideration, Kenneth Blake Nelson

Graduate Theses and Dissertations

In the past, histidine warranted little concern from poultry nutritionists because it was seldom deficient in practical broiler diets. With most essential amino acids now commercially available as feed-grade forms to partially replace intact protein ingredients, histidine and its minimum in least-cost formulation are receiving fresh attention. Published histidine requirement data for broilers are sparce, and many of these studies have been conducted on males within the first three weeks post-hatch. Moreover, rudimentary dose-response experimental designs may not be applicable to estimate histidine requirements in later growth periods because histidine is uniquely stored within the body. In times of dietary …


Chemostratigraphic And Paleoclimatic Studies Of Cloverly Formation, Northern Wyoming, U.S.A, Queen Amarachi Kalu Aug 2023

Chemostratigraphic And Paleoclimatic Studies Of Cloverly Formation, Northern Wyoming, U.S.A, Queen Amarachi Kalu

Graduate Theses and Dissertations

The Early – Late Cretaceous transition in Western North America recorded a period of rapid climatic and tectonic change in Earth’s history. Major climate events associated with large igneous province eruptions caused several instances of ocean anoxic events (OAE) and perturbations to the global carbon (C) – cycle. These perturbations to the global C-cycle are observed in the bulk organic C record of both marine and terrestrial deposits and can be used to correlate units across major depositional basins. Major efforts are being made to generate time-constrained palaeontologic and paleoclimate information from the North American Cordilleran foreland basin and C-isotope …


Dual Ni/Co-Hemin Metal-Organic Framework-Prgo For High-Performance Asymmetric Hybrid Supercapacitor, Kimia Zarean Mousaabadi, Ali A. Ensafi, Erfan Naghsh, Jin-Song Hu, Behzad Rezaei Aug 2023

Dual Ni/Co-Hemin Metal-Organic Framework-Prgo For High-Performance Asymmetric Hybrid Supercapacitor, Kimia Zarean Mousaabadi, Ali A. Ensafi, Erfan Naghsh, Jin-Song Hu, Behzad Rezaei

Chemistry & Biochemistry Faculty Publications and Presentations

In this study, we conducted direct synthesis of a dual metal–organic framework (Ni/Co-Hemin MOF) on phosphorous-doped reduced graphene oxide (PrGO) to serve as an active material in high-performance asymmetrical supercapacitors. The nanocomposite was utilized as an active material in supercapacitors, exhibiting a noteworthy specific capacitance of 963 C g−1 at 1.0 A g−1, along with a high rate capability of 68.3% upon increasing the current density by 20 times, and superior cycling stability. Our comprehensive characterization and control experiments indicated that the improved performance can be attributed to the combined effect of the dual MOF and the …


Integrated And Monolithic Iii-Nitride Devices Grown By Mbe, Rohith Allaparthi Aug 2023

Integrated And Monolithic Iii-Nitride Devices Grown By Mbe, Rohith Allaparthi

Graduate Theses and Dissertations

III-Nitride (III-N) semiconductors with wide bandgap (WBG) characteristics offer promising advancements for high power density, high voltage, and high-frequency applications, presenting a promising alternative to traditional silicon (Si) technology. However, native substrate material for the majority of WBG semiconductors is still not commercially affordable. Because of its highly mature progression, utilizing standard Si wafers as substrates is a cost-effective alternative. This dissertation explores the development of electronic devices based on III-N thin films, grown monolithically via molecular beam epitaxy (MBE), followed by several processing techniques. Initially, a heterojunction p-n diode is realized, incorporating the growth of single-crystal WBG AlN films …


Short-Term Response In Soil Health To Management Practices Within Large- And Small-Scale Cropping Systems In Arkansas, Torri Holder Aug 2023

Short-Term Response In Soil Health To Management Practices Within Large- And Small-Scale Cropping Systems In Arkansas, Torri Holder

Graduate Theses and Dissertations

Improving soil health is a growing area of interest within large- and small-scale agricultural systems in Arkansas as producers face increasing input costs, increased awareness of variability and intensity in extreme weather events, decreasing resource availability, and suboptimal productivity related to environmental degradation. Practices aimed at improving soil health such as cover cropping and the use of organic amendments are increasingly recommended and adopted; however, research on optimal management in the Mid-South is lacking. Two studies were conducted to evaluate the effectiveness of soil health management under both small- and large-scale farming operations in Arkansas. The objective of the small-scale …


Nutrient Responses To Hippuric Acid In Sheep Urine Applied To Pasture Soil Cores, Ethan Avery Collins Aug 2023

Nutrient Responses To Hippuric Acid In Sheep Urine Applied To Pasture Soil Cores, Ethan Avery Collins

Graduate Theses and Dissertations

Hippuric acid is a breakdown product of tannins, which bind with proteins in the animal rumen and slow down protein metabolism, thus increasing nitrogen (N) retention in the animal. Increased hippuric acid concentration in bovine and ovine urine applied to soil may decrease rates of nitrification, denitrification, and nitrous oxide fluxes in pasture soils. Additionally, condensed tannins have increased rates of carbon mineralization when incorporated in humus and leaf litter. To evaluate effects of hippuric acid concentration, treatments of urine from sheep fed a tannin-supplemented diet, synthetic urine, or urea controls were applied to intact soil cores seeded with crabgrass …


Investigation Of The Flow Field In The Jack Rabbit Ii Mock Urban Environment Field Tests Using A 1:50 Scale Wind Tunnel Model, Paulo Victor De Freitas Lopes Aug 2023

Investigation Of The Flow Field In The Jack Rabbit Ii Mock Urban Environment Field Tests Using A 1:50 Scale Wind Tunnel Model, Paulo Victor De Freitas Lopes

Graduate Theses and Dissertations

Accidental release of toxic chemicals can put workers and nearby populations at significant risk. Consequence assessment of accidents in urban environments is of particular interest. Urban geometries create wind channels between buildings, along with particularly dangerous areas downwind of buildings, where near-stagnant flow is present. Furthermore, recirculation zones can be formed between buildings, trapping high concentrations of toxic gases at ground level, particularly for denser-than-air gases. In 2015, the Department of Homeland Security conducted the Jack Rabbit II Field Test (JR-II) at Dugway Proving Ground, UT. During JR-II, chlorine was released at the center of a Mock Urban Environment (MUE) …


Photon Counting Statistics Of Classical And Quantum Light Sources, Luis Felipe Morales Bultron Aug 2023

Photon Counting Statistics Of Classical And Quantum Light Sources, Luis Felipe Morales Bultron

Graduate Theses and Dissertations

Multiple sources of light, including coherent light, thermal light, light from a degenerate parametric oscillation and resonance fluorescence from a two level coherently driven atom are considered for the analysis of their wait time statistics. We include the second order normalized correlation function and Mandel's Q parameter for brief discussion. A general framework to analyze the generalized conditional and unconditional wait time distributions is also obtained in order to understand the photo-count statistics of the light sources included in this work. Average and variance of wait times with respect to both unconditional and conditional wait time distribution are also obtained …


Circuitry And Semiconductor Studies For Making A Graphene Energy Harvesting Device, Ferdinand Harerimana Aug 2023

Circuitry And Semiconductor Studies For Making A Graphene Energy Harvesting Device, Ferdinand Harerimana

Graduate Theses and Dissertations

Freestanding graphene has constantly moving ripples. Due to its extreme flexibility, graphene responds to ambient vibrations and changes its curvature from concave to convex and vice versa. During a ripple inversion 10,000 atoms move together, suggesting the presence of kinetic energy which can be harvested. In this study we present circuitry and semiconductor studies for harvesting energy from graphene vibrations. The goal of the study is to develop a graphene energy harvesting chip which can serve as a battery replacement in low power electronics. In the first study we determined the best circuit for harvesting vibrational low power. To do …


The Multiverse Argument For The Existence Of God, Michael Dover Aug 2023

The Multiverse Argument For The Existence Of God, Michael Dover

Graduate Theses and Dissertations

The Fine-Tuning Argument for the Existence of God is one of the most powerful arguments in favor of God’s existence. Perhaps the most common objection to this argument involves the Multiverse Theory, which posits an infinite or very large multiverse, adequately explaining the fine-tuning of the universe without positing an intelligent designer. Thus, the Multiverse Theory is often posited as a way of maintaining Atheism. In this paper, I argue that the Atheistic Multiverse View is untenable: if the multiverse exists, God or gods are highly likely to exist as well. Additionally, this paper explores topics like: the conceivability of …


Towards Multi-Modal Explainable Video Understanding, Kashu Yamazaki Aug 2023

Towards Multi-Modal Explainable Video Understanding, Kashu Yamazaki

Graduate Theses and Dissertations

This thesis presents a novel approach to video understanding by emulating human perceptual processes and creating an explainable and coherent storytelling representation of video content. Central to this approach is the development of a Visual-Linguistic (VL) feature for an interpretable video representation and the creation of a Transformer-in-Transformer (TinT) decoder for modeling intra- and inter-event coherence in a video. Drawing inspiration from the way humans comprehend scenes by breaking them down into visual and non-visual components, the proposed VL feature models a scene through three distinct modalities. These include: (i) a global visual environment, providing a broad contextual understanding of …


Generating Health-Promoting Bioactive Compounds And Nanoporous Materials From Rice Processing Byproducts Via Supercritical Carbon Dioxide Technology, Sumanjot Kaur Aug 2023

Generating Health-Promoting Bioactive Compounds And Nanoporous Materials From Rice Processing Byproducts Via Supercritical Carbon Dioxide Technology, Sumanjot Kaur

Graduate Theses and Dissertations

Rice husk and bran, byproducts of rice processing, are generated in large quantities (~30-40% of the total rice weight) and are discarded as waste or burned in an open field, creating a major disposal problem for the rice industry. However, these byproducts contain high-value compounds, including phytochemicals, fiber, and proteins. Therefore, the goal of this study was to generate high-value food ingredients from rice processing byproducts using a green, innovative approach based on supercritical carbon dioxide (SC-CO2) technology. Specific objectives were to (i) extract health-promoting phytochemicals from rice husk and (ii) convert rice bran into nanoporous materials using SC-CO2. First, …


Examining The Perceived Implications Of Eliminating The Stem Career Cluster In Kansas, Trevor Maiseroulle Aug 2023

Examining The Perceived Implications Of Eliminating The Stem Career Cluster In Kansas, Trevor Maiseroulle

Graduate Theses and Dissertations

Career and technical education (CTE) has been an effort in the United States to help bring quality career preparation programs to secondary schools nationwide, with many career clusters allowing schools to teach various courses. For example, the science, technology, engineering, and mathematics (STEM) career cluster provides interdisciplinary approaches and hands-on activities to help students succeed in postsecondary ventures. One of the integral subjects in STEM education is technology and engineering education (T&EE), which has been synonymous with STEM education for decades. T&EE is a discipline which has been around for over a century, nevertheless it may be confused with CTE. …


Method Of Efficiently Constructing Negatively Curved Surfaces From Flat Material, Chaim Goodman-Strauss, Eugene Sargent Jul 2023

Method Of Efficiently Constructing Negatively Curved Surfaces From Flat Material, Chaim Goodman-Strauss, Eugene Sargent

Patents Granted

An object having a plurality of negative curvatures comprising a plurality of planar sections adjoined together by locking segments.


The Appropriateness Of Outlier Exclusion Approaches Depends On The Expected Contamination: Commentary On André (2022), Daniel Villanova Jul 2023

The Appropriateness Of Outlier Exclusion Approaches Depends On The Expected Contamination: Commentary On André (2022), Daniel Villanova

Marketing Faculty Publications and Presentations

In a recent article, André (2022) addressed the decision to exclude outliers using a threshold across conditions or within conditions and offered a clear recommendation to avoid within-conditions exclusions because of the possibility for large false-positive inflation. In this commentary, I note that André’s simulations did not include the situation for which within-conditions exclusion has previously been recommended—when across-conditions exclusion would exacerbate selection bias. Examining test performance in this situation confirms the recommendation for within-conditions exclusion in such a circumstance. Critically, the suitability of exclusion criteria must be considered in relationship to assumptions about data-generating mechanisms.


Interpolation Problems And The Characterization Of The Hilbert Function, Bryant Xie Jul 2023

Interpolation Problems And The Characterization Of The Hilbert Function, Bryant Xie

Mathematical Sciences Undergraduate Honors Theses

In mathematics, it is often useful to approximate the values of functions that are either too awkward and difficult to evaluate or not readily differentiable or integrable. To approximate its values, we attempt to replace such functions with more well-behaving examples such as polynomials or trigonometric functions. Over the algebraically closed field C, a polynomial passing through r distinct points with multiplicities m1, ..., mr on the affine complex line in one variable is determined by its zeros and the vanishing conditions up to its mi − 1 derivative for each point. A natural question would then be to consider …


Freestanding Graphene Heat Engine Analyzed Using Stochastic Thermodynamics, J. Durbin, J. M. Mangum, M. N. Gikunda, F. Harerimana, P. Kumar, L. L. Bonilla, P. M. Thibado Jul 2023

Freestanding Graphene Heat Engine Analyzed Using Stochastic Thermodynamics, J. Durbin, J. M. Mangum, M. N. Gikunda, F. Harerimana, P. Kumar, L. L. Bonilla, P. M. Thibado

Physics Faculty Publications and Presentations

We present an Ito-Langevin model for freestanding graphene connected to an electrical circuit. The graphene is treated as a Brownian particle in a double-well potential and is adjacent to a fixed electrode to form a variable capacitor. The capacitor is connected in series with a battery and a load resistor. The capacitor and resistor are given separate thermal reservoirs. We have solved the coupled Ito-Langevin equations for a broad range of temperature differences between the two reservoirs. Using ensemble averages, we report the rate of change in energy, heat, and work using stochastic thermodynamics. When the resistor is held at …


The Large Deficit Of Hmxb Emission From Luminous Infrared Galaxies: The Case Of The Circumnuclear Starburst Ring In Ngc 7552, Lacey West, Kristen Garofali, Bret D. Lehmer, Andrea Prestwich, Rafael Eufrasio, Wasutep Luangtip, Timothy P. Roberts, Andreas Zezas Jul 2023

The Large Deficit Of Hmxb Emission From Luminous Infrared Galaxies: The Case Of The Circumnuclear Starburst Ring In Ngc 7552, Lacey West, Kristen Garofali, Bret D. Lehmer, Andrea Prestwich, Rafael Eufrasio, Wasutep Luangtip, Timothy P. Roberts, Andreas Zezas

Physics Faculty Publications and Presentations

Luminous infrared galaxies (LIRGs), the most extreme star-forming galaxies in the nearby (D < 30 Mpc) universe, show a notable X-ray emission deficiency (up to a factor of ∼10) compared with predictions from scaling relations of galaxy-wide high-mass X-ray binary (HMXB) luminosity with star formation rate. In the nearby (≈20 Mpc) LIRG NGC 7552, the majority of the IR emission originates in a circumnuclear starburst ring, which has been resolved into several discrete knots of star formation. We present results from recent Chandra observations of NGC 7552, which reveal significant deficits in the 2–7 keV X-ray luminosities from two of the most powerful star-forming knots. We hypothesize that the expected luminous HMXB populations in these knots are either (1) obscured by very large column densities or (2) suppressed due to the knots having relatively high metallicity and/or very young ages (≲5 Myr). We distinguish between these possibilities using data from recent NuSTAR observations, whose sensitivity above 10 keV is capable of uncovering heavily obscured HMXB populations, since emission at these energies is more immune to absorption effects. We find no evidence of a heavily obscured HMXB population in the central region of NGC 7552, suggesting suppressed HMXB formation. We further show that metallicity-dependent scaling relations cannot fully account for the observed deficit from the most powerful star-forming knots or the central region as a whole. Thus, we suggest that recent bursts in local star formation activity likely drive the high LIR within these regions on timescales ≲5 Myr, shorter than the timescale required for the formation of HMXBs.


Er Translocon Inhibitor Ipomoeassin F Inhibits Triple-Negative Breast Cancer Growth Via Blocking Er Molecular Chaperones, Shishi Tao, Eun Ju Yang, Guanghui Zong, Pui Kei Mou, Guowen Ren, Liang Chen, Ho Jeong Kwon, Jianhong Zhou, Zhijian Hu, Arman Khosravi, Qingyang Zhang, Yuchun Du, Wei Q. Shi, Joong Sup Shim Jul 2023

Er Translocon Inhibitor Ipomoeassin F Inhibits Triple-Negative Breast Cancer Growth Via Blocking Er Molecular Chaperones, Shishi Tao, Eun Ju Yang, Guanghui Zong, Pui Kei Mou, Guowen Ren, Liang Chen, Ho Jeong Kwon, Jianhong Zhou, Zhijian Hu, Arman Khosravi, Qingyang Zhang, Yuchun Du, Wei Q. Shi, Joong Sup Shim

Biological Sciences Faculty Publications and Presentations

Triple-negative breast cancer (TNBC) is an aggressive type of breast cancer where no effective therapy has been developed. Here, we report that the natural product ER translocon inhibitor ipomoeassin F is a selective inhibitor of TNBC cell growth. A proteomic analysis of TNBC cells revealed that ipomoeassin F significantly reduced the levels of ER molecular chaperones, including PDIA6 and PDIA4, and induced ER stress, unfolded protein response (UPR) and autophagy in TNBC cells. Mechanistically, ipomoeassin F, as an inhibitor of Sec61α-containing ER translocon, blocks ER translocation of PDIA6, inducing its proteasomal degradation. Silencing of PDIA6 or PDIA4 by RNA interferences …


Revisiting The Properties Of X-Ray Active Galactic Nuclei In The Ssa22 Protocluster: Normal Supermassive Black Hole And Host-Galaxy Growth For Agns In A Z=3.09 Overdensity, Erik B. Monson, Keith Doore, Rafael T. Eufrasio, Bret D. Lehmer, David M. Alexander, Chris M. Harrison, Mariko Kubo, Cristian Saez, Hideki Umehata Jul 2023

Revisiting The Properties Of X-Ray Active Galactic Nuclei In The Ssa22 Protocluster: Normal Supermassive Black Hole And Host-Galaxy Growth For Agns In A Z=3.09 Overdensity, Erik B. Monson, Keith Doore, Rafael T. Eufrasio, Bret D. Lehmer, David M. Alexander, Chris M. Harrison, Mariko Kubo, Cristian Saez, Hideki Umehata

Physics Faculty Publications and Presentations

We analyze the physical properties of eight X-ray-selected active galactic nuclei (AGNs) and one candidate protoquasar system (ADF22A1) in the z = 3.09 SSA22 protocluster by fitting their X-ray-to-IR spectral energy distributions (SEDs) using our SED-fitting code, Lightning (https://www.github.com/rafaeleufrasio/lightning). We recover star formation histories (SFHs) for seven of these systems which are well fit by composite stellar population plus AGN models. We find indications that four out of nine of the SSA22 AGN systems we study have host galaxies below the main sequence, with SFR/SFRMS ≤ −0.4. The remaining SSA22 systems, including ADF22A1, are consistent with obscured supermassive black hole …


Tribological Behavior Of Polydopamine/Polytetrafluoroethylene Coating On Laser Textured Stainless Steel With Hilbert Curves, Firuze Soltani-Kordshuli, Nathaniel Harris, Min Zou Jul 2023

Tribological Behavior Of Polydopamine/Polytetrafluoroethylene Coating On Laser Textured Stainless Steel With Hilbert Curves, Firuze Soltani-Kordshuli, Nathaniel Harris, Min Zou

Mechanical Engineering Faculty Publications and Presentations

Shallow Hilbert curve patterns with easily programmable texture density were selected for laser texturing of stainless steel substrates. Two different texture path segment lengths (12 and 24 mu m) and four different laser power percentages (5%, 10%, 15%, and 20%) were investigated. The textured and smooth substrates were coated with thin polydopamine/polytetrafluoroethylene (PDA/PTFE) coatings for tribological property assessment. The effects of texture density (texture area coverage) and laser power on the durability and friction of the coated surfaces were studied. Laser texturing the substrates improved the coating durability up to 25 times, reduced the friction coefficient, and prevented coating global …


Hurricane Impacts On Land In The Central And Eastern Caribbean Since 1494 Ce From Written Records, Michael Chenoweth, Ian Howard Jul 2023

Hurricane Impacts On Land In The Central And Eastern Caribbean Since 1494 Ce From Written Records, Michael Chenoweth, Ian Howard

Geosciences Faculty Publications and Presentations

Written accounts of hurricanes and their impacts in the Caribbean region date back to 1494 CE We report a new compilation of hurricanes in the longest settled regions of the central and eastern Caribbean region (CECR) that is the most complete yet produced and present basic statistics. We assess likely undercounts of hurricanes due to incomplete documentary records in the earliest part of the record by using the most complete reporting from Puerto Rico relative to the remainder of the CECR. We compare our results with other documentary and proxy data from the region and demonstrate using wavelet analysis significant …


Forecasting Sea Level Rise-Driven Inundation In Diked And Tidally Restricted Coastal Lowlands, K. M. Befus, A. P.D. Kurnizki, K. D. Kroeger, M. J. Eagle, T. P. Smith Jul 2023

Forecasting Sea Level Rise-Driven Inundation In Diked And Tidally Restricted Coastal Lowlands, K. M. Befus, A. P.D. Kurnizki, K. D. Kroeger, M. J. Eagle, T. P. Smith

Geosciences Faculty Publications and Presentations

Diked and drained coastal lowlands rely on hydraulic and protective infrastructure that may not function as designed in areas with relative sea-level rise. The slow and incremental loss of the hydraulic conditions required for a well-drained system make it difficult to identify if and when the flow structures no longer discharge enough water, especially in tidal settings where two-way flows occur through the dike. We developed and applied a hydraulic mass-balance model to quantify how water levels in the diked and tidally restricted coastal wetlands and water bodies dynamically respond to sea-level rise, specifically applied to the Herring River Estuary …