Physical Sciences and Mathematics Commons^™

Least Flycatchers Under-Reported In Fall Migration In Arkansas —A Citizen Science Conundrum, L. Barnes, R. Kannan

Journal of the Arkansas Academy of Science

The Least Flycatcher Empidonax minimus is a small passerine migrant bird that passes through Arkansas in fall and spring migration. The birds are vocal during spring passage but relatively quiet and unobtrusive during fall migration, leading to many fewer reports by birdwatchers in fall than spring. We use eBird maps and data to present evidence to support this discrepancy between fall and spring observations. We also show that the species is under-reported in Arkansas during the fall compared to neighboring regions. This may be in part due to the reluctance of some birders to provide the minimal evidence required to …

The Rayleigh Problem (Random Flights) Is Everywhere Redux, John E. Gray, Stephen R. Addison

Journal of the Arkansas Academy of Science

The phase noise problem (or Rayleigh problem) occurs in all aspects of radar. It is an effect that a radar engineer or physicist always has to take into account as part of a design or in an attempt to characterize the physics of a problem such as reverberation. Normally, the mathematical difficulties of phase noise characterization are avoided by assuming the phase noise probability distribution function (PDF) is uniformly distributed, and the Central Limit Theorem (CLT) is invoked to argue that the superposition of relatively few random components obey the CLT and hence the superposition can be treated as a …

Unttangling Irregular Actin Cytoskeleton Architectures In Tomograms Of The Cell With Struwwel Tracer, Salim Sazzed, Peter Scheible, Jing He, Willy Wriggers

Computer Science Faculty Publications

In this work, we established, validated, and optimized a novel computational framework for tracing arbitrarily oriented actin filaments in cryo-electron tomography maps. Our approach was designed for highly complex intracellular architectures in which a long-range cytoskeleton network extends throughout the cell bodies and protrusions. The irregular organization of the actin network, as well as cryo-electron-tomography-specific noise, missing wedge artifacts, and map dimensions call for a specialized implementation that is both robust and efficient. Our proposed solution, Struwwel Tracer, accumulates densities along paths of a specific length in various directions, starting from locally determined seed points. The highest-density paths originating …

Copula-Based Models For Bivariate And Multivariate Zero-Inflated Count Time Series Data, Dimuthu Fernando, Norou Diawara

College of Sciences Posters

Count time series data have multiple applications. The applications can be found in areas of finance, climate, public health and crime data analyses. In some scenarios, count time series come as multivariate vectors that exhibit not only serial dependence within each time series but also with cross correlation among the series. When considering these observed counts, analysis presents crucial challenges when a value, say zero, occurs more often than usual. There is presence of zero-inflation in the data.

In this presentation, we mainly focus on modeling bivariate zero-inflated count time series model based on a joint distribution of the two …

Ml-Based Surrogates And Emulators, Tareq Alghamdi, Yaohang Li, Nobuo Sato

College of Sciences Posters

No abstract provided.

A Novel Parking Management In Smart City Vehicular Datacenters, Syed Rizvi, Susan Zehra, Steven Olariu

College of Sciences Posters

Researchers have shown that most vehicles spend the majority of their time parked in parking garages, lots, or driveways. During this time, their computing resources are unused and untapped. This has led to substantial interest in Vehicular Cloud, an area of research in which each vehicle acts as a computation node. The main difference between traditional cloud computing and vehicular cloud computing is the availability of nodes. In traditional clouds, nodes are available 24/7, while in vehicular clouds, nodes (vehicles) are only available while parked in parking lots. This creates a dynamic environment as vehicles enter and exit parking garages …

Robustembed: Robust Sentence Embeddings Using Self-Supervised Contrastive Pre-Training, Javad Asl, Eduardo Blanco, Daniel Takabi

School of Cybersecurity Faculty Publications

Pre-trained language models (PLMs) have demonstrated their exceptional performance across a wide range of natural language processing tasks. The utilization of PLM-based sentence embeddings enables the generation of contextual representations that capture rich semantic information. However, despite their success with unseen samples, current PLM-based representations suffer from poor robustness in adversarial scenarios. In this paper, we propose RobustEmbed, a self-supervised sentence embedding framework that enhances both generalization and robustness in various text representation tasks and against diverse adversarial attacks. By generating high-risk adversarial perturbations to promote higher invariance in the embedding space and leveraging the perturbation within a novel contrastive …

A Global Comparison Of Marine Chlorophyll Variability Observed In Eulerian And Lagrangian Perspectives, Angela M. Kuhn, Matthew Mazloff, Stephanie Dutkiewicz, Oliver Jahn, Sophie Clayton, Tatiana Rynearson, Andrew D. Barton

OES Faculty Publications

The California Current System is a diatom‐dominated region characterized by seasonal coastal upwelling and additional elevated mesoscale activity. Cyclonic mesoscale eddies in the region trap productive coastal waters with their planktonic communities and transport them offshore with limited interaction with surrounding waters, effectively acting as natural mesocosms, where phytoplankton populations undergo ecological succession as eddies age. This study examines diatom community composition within two mesoscale cyclonic eddies that formed in the same region of the California Current System 2 months apart and in the California Current waters surrounding them. The diatom communities were analyzed in the context of shifting environmental …

Levels Of Autotrophy And Heterotrophy In Mesophotic Corals Near The End Photic Zone, Amy Carmignani, Veronica Z. Radice, Kathryn M. Mcmahon, Alex I. Holman, Karen Miller, Kliti Grice, Zoe Richards

Biological Sciences Faculty Publications

Mesophotic corals live at ~30-150 m depth and can sustain metabolic processes under light-limited conditions by enhancing autotrophy through specialized photoadaptations or increasing heterotrophic nutrient acquisition. These acclimatory processes are often species-specific, however mesophotic ecosystems are largely unexplored and acclimation limits for most species are unknown. This study examined mesophotic coral ecosystems using a remotely operated vehicle (Ashmore Reef, Western Australia at 40–75m depth) to investigate the trophic ecology of five species of scleractinian coral (from genera Leptoseris, Pachyseris, and Craterastrea) using stable isotope analyses (δ¹³C and δ¹⁵N) of host and symbiont tissues …

Disparate Population And Holobiont Structure Of Pocilloporid Corals Across The Red Sea Gradient Demonstrate Species-Specific Evolutionary Trajectories, Carol Buitrago-López, Anny Cárdenas, Benjamin C.C. Hume, Thierry Gosselin, Fabian Staubach, Manuel Aranda, Daniel J. Barshis, Yvonne Sawall, Christian R. Voolstra

Biological Sciences Faculty Publications

Global habitat degradation heightens the need to better understand patterns of genetic connectivity and diversity of marine biota across geographical ranges to guide conservation efforts. Corals across the Red Sea are subject to pronounced environmental differences, but studies so far suggest that animal populations are largely connected, excepting evidence for a genetic break between the northern-central and southern regions. Here, we investigated population structure and holobiont assemblage of two common pocilloporid corals, Pocillopora verrucosa and Stylophora pistillata, across the Red Sea. We found little evidence for population differentiation in P. verrucosa, except for the southernmost site. Conversely, S. …

A Multi-Taxon Analysis Of European Red Lists Reveal Major Threats To Biodiversity, Axel Hochkirch, Melanie Bilz, Catarina C. Ferreira, Anja Danielczak, David Allen, Ana Nieto, Carlo Rondinini, Kate Harding, Craig Hilton-Taylor, Caroline M. Pollock, Mary Seddon, Jean-Christophe Vié, Keith N. A. Alexander, Emily Beech, Manuel Biscoito, Yoan Braud, Ian J. Burfield, Filippo Maria Buzzetti, Marta Cálix, Kent E. Carpenter, Ning Labbish Chao, Dragan Chobanov, Maarten J. M. Christenhusz, Bruce B. Collette, Mia T. Comeros-Raynal, Neil Cox, Matthew Craig, Annabelle Cuttelod, William R. T. Darwall, Benoit Dodelin, Nicholas K. Dulvy, Eve Englefield, Michael F. Fay, Nicholas Fettes, Jörg Freyhof, Silvia García, Mariana García Criado, Michael Harvey, Nick Hodgetts, Christina Ieronymidou, Vincent J. Kalkman, Shelagh P. Kell, James Kemp, Sonia Khela, Richard V. Lansdown, Julia M. Lawson, Danna J. Leaman, Joana Magos Brehm, Nigel Maxted, Rebecca M. Miller, Eike Neubert, Baudewijn Odé, David Pollard, Riley Pollom, Rob Pople, Juan José Presa Asensio, Gina M. Ralph, Hassan Rankou, Malin Rivers, Stuart P. M. Roberts, Barry Russell, Alexander Sennikov, Fabien Soldati, Anna Staneva, Emilie Stump, Andy Symes, Dmitry Telnov, Helen Temple, Andrew Terry, Anastasiya Timoshyna, Chris Van Swaay, Henry Väre, Rachel H. L. Walls, Luc Willemse, Brett Wilson, Jemma Window, Emma G. E. Wright, Thomas Zuna-Kratky

Biological Sciences Faculty Publications

Biodiversity loss is a major global challenge and minimizing extinction rates is the goal of several multilateral environmental agreements. Policy decisions require comprehensive, spatially explicit information on species’ distributions and threats. We present an analysis of the conservation status of 14,669 European terrestrial, freshwater and marine species (ca. 10% of the continental fauna and flora), including all vertebrates and selected groups of invertebrates and plants. Our results reveal that 19% of European species are threatened with extinction, with higher extinction risks for plants (27%) and invertebrates (24%) compared to vertebrates (18%). These numbers exceed recent IPBES (Intergovernmental Platform on Biodiversity …

Biodiversity Of Philippine Marine Fishes: A Dna Barcode Reference Library Based On Voucher Specimens, Katherine E. Bemis, Matthew G. Girard, Mudjekeewis D. Santos, Kent E. Carpenter, Jonathan R. Deeds, Diane E. Pitassy, Nicko Amor L. Flores, Elizabeth S. Hunter, Amy C. Driskell, Kenneth S. Macdonald Iii, Lee A. Weigt, Jeffrey T. Williams

Biological Sciences Faculty Publications

Accurate identification of fishes is essential for understanding their biology and to ensure food safety for consumers. DNA barcoding is an important tool because it can verify identifications of both whole and processed fishes that have had key morphological characters removed (e.g., filets, fish meal); however, DNA reference libraries are incomplete, and public repositories for sequence data contain incorrectly identified sequences. During a nine-year sampling program in the Philippines, a global biodiversity hotspot for marine fishes, we developed a verified reference library of cytochrome c oxidase subunit I (COI) sequences for 2,525 specimens representing 984 species. Specimens were primarily purchased …

Marine Heatwaves Modulate The Genotypic And Physiological Responses Of Reef-Building Corals To Subsequent Heat Stress, Kristen T. Brown, Amatzia Genin, Matheus A. Mello-Athayde, Ellie Bergstrom, Adriana Campili, Aaron Chai, Sophie G. Dove, Maureen Ho, Devin Rowell, Eugenia M. Sampayo, Veronica Z. Radice

Biological Sciences Faculty Publications

Back-to-back marine heatwaves in 2016 and 2017 resulted in severe coral bleaching and mortality across the Great Barrier Reef (GBR). Encouragingly, some corals that survived these events exhibit increased bleaching resistance and may represent thermally tolerant populations that can better cope with ocean warming. Using the GBR as a natural laboratory, we investigated whether a history of minimal (Heron Island) or severe (Lizard Island) coral bleaching in 2016 and 2017 equates to stress tolerance in a successive heatwave (2020). We examined the genetic diversity, physiological performance, and trophic plasticity of juvenile (<10 cm) and adult (>25 cm) corals of two common genera ( …

Dataset For Gendered Language, Shweta Soundararajan

Datasets

Gendered language is the use of words that denote an individual’s gender. This can be explicit where the gender is evident in the actual word used, e.g. mother, she, man, but it can also be implicit where social roles or behaviours can signal an individual’s gender - for example, expectations that women display communal traits (e.g., affectionate, caring, gentle) and men display agentic traits (e.g., assertive, competitive, decisive). The use of gendered language in NLP systems can perpetuate gender stereotypes and bias. This paper proposes an approach to generating gendered language datasets using ChatGPT which will provide data for data-driven …

Bioanalytical Studies Of Disease Protein Profiles: Maldi-Tof Ms, Prajkta Satish Chivte

Graduate Research Theses & Dissertations

Coronavirus disease-2019 (COVID-19), which is caused by a novel coronavirus named severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), has ravaged the world for the past 3 years. Even today, there still exists a need for rapid, accurate, economical and non-invasive diagnostic testing platforms that yield high specificity and sensitivity towards the constantly mutating SARS-CoV-2. Research has consistently indicated saliva to be a more amenable specimen type for early detection of SARS-CoV-2, compared to the oral and nasopharyngeal swabs. Considering the limitations and high demand of the existing COVID-19 testing platforms, this dissertation work studies used MALDI-ToF MS (matrix-assisted laser desorption/ionization-time of …

Alignment And Range Verification In Proton Therapy Using Proton Radiography And Proton Ct, Joseph Piet

Graduate Research Theses & Dissertations

Protons are used in radiation therapy to lower doses to healthy tissues by utilizing their Bragg peak. Protons can be used both in imaging and treatment. One of the uses of protons in imaging we tested is its use to align patients using a single beam's eye proton radiograph (pRad). By using a beam's eye pRad, and comparing the water equivalent thickness (WET) to proton digitally reconstructed radiographs (pDRRs), we show that we can measure the best alignment on six axes, three translational and three rotational. This is done by defining a cost function, chi squared, which quantifies the misalignment …

Structural Analysis Of Polar Aggregates And Inter-Ionic Distances In Room Temperature Ionic Liquids, Emily Elizabeth Dalbey

Graduate Research Theses & Dissertations

Ionic liquids have a wide variety of applications in chemistry due to their unique properties such as low flammability, low volatility, and high thermal and chemical stability. These properties make them great solvents, electrolytes for lithium-ion batteries, and more. Ionic liquids are salts whose components are mis-matched in size and shape leading to low melting points. To design an ionic liquid with a desired property it is key to first understand their structure. Lineshape analysis of the charge alternation peak from the experimentally measured or computationally calculated X-ray scattering data can give information about the size of the polar aggregates …

Visualizing Dynamic Multivariate Networks, Bharat Kumar Kale

Graduate Research Theses & Dissertations

Many real-world networks are multivariate in nature and also evolve over time. Such a network whose nodes and/or edges along with their associated attributes, evolve over time is called A dynamic multivariate network (DMVN). For instance, in the scholarly community, researchers often collaborate with others. These collaborations have various attributes, such as scientific domain and number of publications, as well as they change over time. At any given point in time, the collaborations among researchers can be modeled as a network resulting in a collaboration network. When the changes in collaborations and associated attributes are also included in the network, …

The Impact Of Faculty Composition On Cost Per Student: A Mixed Model Approach, Arun Sleeba

Graduate Research Theses & Dissertations

This thesis aims to explore whether research universities in the United States, specifically those classified as Carnegie I or II institutions, utilize part time contingent faculty(rPTF) as a cost saving strategy. Additionally, it sought to determine if there was a differential impact on total costs when comparing public and private universities. Employing a linear mixed effects model with random intercept and slopes, this study analyzed the relationship between rPTF (ratio of part-time to total faculty) and total cost. This study did not provide substantial evidence to support the notion despite observing a negative correlation between rPTF and total cost. Regarding …

A State Space Modeling Approach To Eeg Artifact Removal, Patrick B. Rafael

Graduate Research Theses & Dissertations

In this work, a state space modeling approach is applied to an Electroencephalography(EEG) recording for the purpose of artifact removal, and is compared against Independent Components Analysis (ICA), the current gold standard. Issues of model identifiability are touched on, and Hamiltonian Monte Carlo (HMC) is used to estimate a linear non-Gaussian state space model. Results show that estimating such a model is a nontrivial matter, and the full utility of the state space approach remains to be demonstrated.

Enhanced Maximum Likelihood Models For Underreported Variables: Extending To Multiple Claims Dimension, Shalaka Sudhanshu Sarpotdar

Graduate Research Theses & Dissertations

This thesis builds upon the foundations laid out in Xia et al. [2023], which explored the utilizationof Maximum Likelihood approach to model misrepresentation data in Generalized Linear Models (GLM) ratemaking models. We introduce the concept of “underreported variables”, a form of insurance misrepresentation where insured individuals provide inaccurate information about risk factors that influence insurance eligibility, premiums, and insured amounts. Unlike fraudulent misrepresentation, underreported variables arise from a lack of awareness regarding the insured’s mental and physical health conditions, rather than fraudulent intent. The study rigorously tests the proposed model using health insurance data and extends its applicability to other …

Systematic Study Of Projection Biases In Weak Lensing Analysis, Prudhvi Raj Varma Chintalapati

Graduate Research Theses & Dissertations

The nature of Dark Energy is possibly one of the most fundamental questions in Physicstoday. Comprising 70% of the energy density of the Universe, and being responsible for the accelerated expansion of the Universe, this mysterious form of energy with negative pressure is challenging our current understanding of the fundamental laws of nature. Cosmological parameters like total relative matter Density Ωm, the normalization of power spectrum σ8 and their combination S8 = σ8 (Ωm/0.3)**0.5 are used to quantify our understanding of the evolution of the large-scale structure in the Universe and shed light on the accelerated expansion, caused by the …

Mechanical Behavior Of Metallic Core-Shell Nanoparticles Under Compressive Loading, Phillip Tomich

Graduate Research Theses & Dissertations

Core/shell metallic nanoparticles have been shown to be a promising material type for additive manufacturing in the aerospace and automotive fields. Within additive manufacturing they will be used to accurately make an array of nanoparticles within the grains of metal matrix composites. This in turn will help to strengthen the material while remaining ductility and light weight. In this study, copper/aluminum core/shell nanoparticles are compressed under [100], [110], [111], and [112] directions to showcase their anisotropic material properties. Models of their individual counterparts were also investigated. There are no previous works showing the deformation mechanisms of copper/aluminum core/shell nanoparticles. Molecular …

Methods For Investigating Geo-Stem Learning Ecosystems: A Case-Study Of Illinois Earth Science Teachers, Cheryl L.B. Manning

Graduate Research Theses & Dissertations

The complex interactions between people and resources in communities that foster innovation can be thought of as ecosystems. These ecosystems have the potential to broaden participation in the geoscience community if we invest in collaborations that map out long-term solutions and career pathways for young community members. Geo-STEM learning ecosystems (GLE) engage local communities in sustainable programs that promote geoscience literacy and inspire people to learn the geosciences. A goal of GLE is to leverage existing social systems and accelerate geo-STEM solutions for society. Thus far, few studies in the geosciences have interrogated what is meant by a “learning ecosystem” …

Insight Into The Nanostructure Of “Water-In-Salt” Solutions: A Saxs/Waxs Study On Imide-Based Lithium Salts Aqueous Solutions, Xinyi Liu

Graduate Research Theses & Dissertations

The fundamental understanding of the liquid electrolytes (LEs) solvation structure and electrode-electrolyte interface behavior is important to the entire electrochemical energy storage field. Understanding the solvation structures from a few angstroms to hundreds of nanometers will undoubtedly lay a good foundation for studying the macroscopic transport properties, such as viscosity and ionic conductivity, of the LEs."Water-in-salt" electrolytes that contain 21 m lithium bis(trifluoromethane sulfonyl)imide (LiTFSI) with excellent electrochemical and physical properties have been extensively investigated. However, the structural understanding of the LiTFSI in water is still lacking. Here, we perform synchrotron X-ray scattering to systemically study the structural variation of …

Using Machine Learning To Predict Student Outcomes, Saba Fatima

Graduate Research Theses & Dissertations

Predicting students’ performance to identify which students are at risk of receiving aD/Fail/Withdraw (DFW) grade and ensuring their timely graduation is not just desirable but also necessary in most educational entities. In the US, not only is the Science, Technology, Engineering, and Mathematics (STEM) major becoming less popular among students, the graduation rate of STEM students is steadily declining. The lack of STEM graduates in the US is a serious problem that will place this country at a disadvantage as a competitor in international technological advancement. In order to secure its status as a technological leader internationally, the US institutions …

Dynamic Overnight Effect On Next Day Stock Market Forecasting, Thomas J. Lee

Graduate Research Theses & Dissertations

Using a cross section of stocks that have high frequency trading data from 2007 to 2018, we document whether various intraday momentum patterns found in the financial literature over the years continue to hold over time. The first half hour return on the market is often seen as having predictive power over the last half hour of trading, or overnight returns are thought to reverse in the next day's first half hour of trading. We find that while there is some evidence for these patterns, especially in the earlier years, these patterns tend to weaken over time as investors take …

Macroeconomic Factors Influencing Foreign Direct Investment In Some Selected Countries In Africa, Richard Essel Mensah

Graduate Research Theses & Dissertations

This paper investigates the possible factors that influence foreign direct investment inflow rate to Africa after controlling for other macroeconomic factors. Using the heterogenous Toeplitz mixed method on a sample of 23 countries from 1998 – 2020, we find evidence of the statistical significance of a relationship between the amount of trade done in Africa and the FDI inflow rate in Africa. We also find a statistical relationship between the labor force participation rate and the FDI inflow rate to Africa. Although the Fixed effect and GLM method did not find the relationship between LFP rate and FDI inflow to …

Coulomb Blockade-Mediated Field Emission Sources Using Ultra-Nanocrystalline Diamond, Jevin Jensen

Graduate Research Theses & Dissertations

Coulomb Blockade effects in field emission provide interesting means of achieving brighter electron sources for numerous applications, ranging from vacuum electronics to the next generation of electron beam technology. Microelectronics cleanroom methods are presented in this thesis for production of field emission sources moderated by the Coulomb Blockade. The use of common processes is an essential step toward widespread experimentation with Coulomb Blockade-mediated field emission apparatuses. The main feature to be explored is the use of nano-diamond films for their potential applicability for this desired outcome. Ultra-Nanocrystalline Diamond is used in two different ways to achieve this, both as a …

The Role Of Machine Learning And Network Analyses In Understanding Microbial Composition In An Experimental Prairie, Ali Eastman Oku

Graduate Research Theses & Dissertations

Machine learning and network analyses are powerful modern tools can process and map out connections between large amount of ecological data from complex environmental communities. Random forests, an ensemble machine learning algorithm, are particularly powerful as they can capture complex patterns in data while remaining easily interpretable. These tools are specifically useful in experimental settings where different types of data are collected. The aim of this study was to demonstrate the utility of machine learning models and network analyses at analyzing diverse ecological data from dynamic plant-soil microbial communities in a prairie ecosystem. Our experimental system is an experimental prairie …