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Full-Text Articles in Physical Sciences and Mathematics

Different Approaches To Overcome Antibiotic Resistance, Samantha Biaesch May 2023

Different Approaches To Overcome Antibiotic Resistance, Samantha Biaesch

Chemistry

In the recent years, there has been a growing demand for the development of antibiotic treatments as bacterial infections have acquired defense mechanisms to commonly used antibiotics, such as penicillin. During the growth of bacterial cells, resistant mutants are able to survive antibiotic treatment and continue proliferation. Thus, creating a resistant bacterial cell population that can no longer be targeted through antibiotic treatment. Due to the recent need of new approaches, there has been an explosion of research in developing techniques that combat bacterial resistance. Both bacteriophage-RNA aptamer binding and modifications in bacterial tRNA show potential to be exploited for …


Evaluating And Improving Snow Prediction In The National Water Model In New York State Using New York State Mesonet Data, Sierra Liotta May 2023

Evaluating And Improving Snow Prediction In The National Water Model In New York State Using New York State Mesonet Data, Sierra Liotta

Atmospheric & Environmental Sciences

When snow melts, the water drains into nearby streams and rivers which can impact water supply and flood hazards. The National Water Model (NWM) provides high quality forecast data for streamflow in the continental United States using mathematical representations of hydrologic processes. This research evaluates how the land surface model (LSM), Noah-MP, in the NWM simulates snowpack and snowmelt in New York State. To evaluate the representation of snow melt in Noah-MP, we examine point simulations at the New York State Mesonet (NYSM) sites where Noah-MP is forced by NYSM meteorological observations to avoid biases in the meteorological input and …


Investigating The Difference Between Members In The High-Resolution Rapid Refresh Ensemble (Hrrre) During The February 23rd, 2022 Winter Storm, Michael Barletta May 2023

Investigating The Difference Between Members In The High-Resolution Rapid Refresh Ensemble (Hrrre) During The February 23rd, 2022 Winter Storm, Michael Barletta

Atmospheric & Environmental Sciences

Probabilistic forecasting is one tool that is being used to help create more accurate and understandable forecasts. Using percentages and probabilities allows for more depth to a forecast and allows forecasters to be able to convey a clearer message of what exactly they are expecting. Ensembles are a set of forecast models that have either different starting conditions, boundary conditions or parameter settings. They are one way of creating probabilistic forecasts and can help in the understanding of the likelihood of a specific outcome. Forecasters use ensembles to attempt to analyze the range of possible outcomes and the likelihood of …


Mapping Galactic Acceleration With Pulsar Timing, Abigail Moran May 2023

Mapping Galactic Acceleration With Pulsar Timing, Abigail Moran

University Scholar Projects

We have conducted a cross match of objects in Gaia Early Data Release 3 and millisecond pulsars (MSPs) in the International Pulsar Timing Array’s Data Release 2 (IPTA DR2) to identify binary systems. Gaia has parallax measurements for these optical companions, which we combine with pulsar timing based parallax measurements to calculate new combined MSP distances. Through this crossmatch with IPTA DR2 we improved five distance measurements and found the first parallax measurement for one MSP.

Using this Gaia crossmatch method now with a well-timed subset of the Australia Telescope National Facility’s database, we found three new pulsar distances. We …


Testing The Use Of Anisotropy Of Magnetic Susceptibility (Ams) In Determining Genetic Origins Of Paleoproterozoic Diamictites, Miles A. Harbury May 2023

Testing The Use Of Anisotropy Of Magnetic Susceptibility (Ams) In Determining Genetic Origins Of Paleoproterozoic Diamictites, Miles A. Harbury

Theses and Dissertations

The Huronian Supergroup (2.4-2.1 Ga) in Ontario, Canada is widely accepted as an important stratigraphic interval for interpreting Paleoproterozoic climate. This is because it contains some of the oldest glaciogenic rocks on the planet. However, massive and poorly-stratified diamictites in the Gowganda Formation of the Huronian Supergroup have varying depositional interpretations among sedimentologists (subglacial, rainout, sediment gravity flow etc.). Diamictites can occur from a variety of processes and, therefore, proper depositional interpretation is essential for unraveling detailed environmental conditions at the time of deposition. Anisotropy of magnetic susceptibility (AMS) looks at the orientation of magnetic particles within a rock and …


Predictive Modeling Of Cave Entrance Locations: Relationships Between Surface And Subsurface Morphology, William Blitch, Adia R. Sovie, Benjamin Tobin May 2023

Predictive Modeling Of Cave Entrance Locations: Relationships Between Surface And Subsurface Morphology, William Blitch, Adia R. Sovie, Benjamin Tobin

Faculty, Staff, and Affiliated Publications--KGS

Cave entrances directly connect the surface and subsurface geomorphology in karst landscapes. Understanding the spatial distribution of these features can help identify areas on the landscape that are critical to flow in the karst groundwater system. Sinkholes and springs are major locations of inflow and outflow from the groundwater system, respectively, however not all sinkholes and springs are equally connected to the main conduit system.

Predicting where on the landscape zones of high connectivity exist is a challenge because cave entrances are difficult to detect and imperfectly documented. Wildlife research has a similar issue of understanding the complexities of where …


Use Of Space And Foraging Behavior Of Loggerhead Shrikes In Urban Areas, Katie Anne Maddox May 2023

Use Of Space And Foraging Behavior Of Loggerhead Shrikes In Urban Areas, Katie Anne Maddox

Electronic Theses and Dissertations

Loggerhead shrikes, Lanius ludovicianus, are a declining grassland songbird native to North America. Land-use change has been associated with the decline of grassland bird species. However, the process of urbanization creates novel short-grass habitats reminiscent of shrikes’ natural habitats. Loggerhead shrikes have been observed living in developed areas, particularly in Southeastern coastal states. Understanding the long-term impacts of urban-dwelling on loggerhead shrike populations is vital to identifying whether urban areas offer refuge or act as an ecological sink for shrike populations.

In chapter one, I quantified the use of space by shrikes in urban habitats within Horry County, South …


Leadership Development In Education For Sustainable Development: Evaluation Of Higher Education Students In Sustainable Development Programs, Michelle Dzurenda May 2023

Leadership Development In Education For Sustainable Development: Evaluation Of Higher Education Students In Sustainable Development Programs, Michelle Dzurenda

Electronic Theses and Dissertations

The United Nations Department of Economic and Social Affairs (UN DESA) has been working decades towards reaching Sustainable Development Goals (SDGs) to create peace and prosperity for people and the planet. The 2030 Agenda was created as an urgent call to action, a global partnership, and a comprehensive plan to work towards the 17 SDGs. For this study, the focus is on Goal 4- quality education and the impact of leadership on Education for Sustainable Development (ESD). Leadership on ESD has been a more recent topic and under researched. By making advancements in leadership on ESD there will be positive …


Program And Proceedings: The Nebraska Academy Of Sciences 1880-2023. 142th Anniversary Year. One Hundred-Thirty-Third Annual Meeting April 21, 2023. Hybrid Meeting: Nebraska Wesleyan University & Online, Lincoln, Nebraska May 2023

Program And Proceedings: The Nebraska Academy Of Sciences 1880-2023. 142th Anniversary Year. One Hundred-Thirty-Third Annual Meeting April 21, 2023. Hybrid Meeting: Nebraska Wesleyan University & Online, Lincoln, Nebraska

Nebraska Academy of Sciences: Programs and Proceedings

AERONAUTICS & SPACE SCIENCE Chairperson(s): Dr. Scott Tarry & Michaela Lucas

HUMANS PAST AND PRESENT Chairperson(s): Phil R. Geib & Allegra Ward

APPLIED SCIENCE & TECHNOLOGY SECTION Chairperson(s): Mary Ettel

BIOLOGY Chairpersons: Lauren Gillespie, Steve Heinisch, and Paul Davis

BIOMEDICAL SCIENCES Chairperson(s): Annemarie Shibata, Kimberly Carlson, Joseph Dolence, Alexis Hobbs, James Fletcher, Paul Denton

CHEM Section Chairperson(s): Nathanael Fackler

EARTH SCIENCES Chairpersons: Irina Filina, Jon Schueth, Ross Dixon, Michael Leite

ENVIRONMENTAL SCIENCE Chairperson: Mark Hammer

PHYSICS Chairperson(s): Dr. Adam Davis

SCIENCE EDUCATION Chairperson: Christine Gustafson

2023 Maiben Lecturer: Jason Bartz

2023 FRIEND OF SCIENCE AWARD TO: Ray Ward …


The Forest Of Claytor Nature Center As A Carbon Offset; Assessing The Sequestration Potential And Socioeconomic Implications, Sarah Mccollum May 2023

The Forest Of Claytor Nature Center As A Carbon Offset; Assessing The Sequestration Potential And Socioeconomic Implications, Sarah Mccollum

Undergraduate Theses and Capstone Projects

Cap and trade programs limit the amount of emissions an organization can produce. To neutralize unavoidable emissions, organizations can purchase carbon offsets from the carbon market. The ability to quantify greenhouse gas emissions offsets in forests increased the urgency and popularity of the carbon market because carbon dioxide (CO2) has a large role in climate change. The University of Lynchburg’s Claytor Nature Center’s 332-acre forest could be a viable revenue source because of its ability to remove CO2 from the atmosphere. In this research, the potential number of annual offsets from Claytor Forest was measured through a manual biomass survey. …


The Role Of Energy Storage In The Transition Toward A Carbon-Neutral Economy, Siyu Feng May 2023

The Role Of Energy Storage In The Transition Toward A Carbon-Neutral Economy, Siyu Feng

Theses and Dissertations

Energy transitions to less-carbon intense technologies, such as wind and solar energy, in the electricity, sector are crucial to realizing international climate goals because the electricity sector has been one of the main global carbon emitter for decades, and environmental plans in most countries involve electrifying heavily polluting industries with clean electricity generation. The intermittency problem of renewable energy has been the main stumbling block on the path, and energy storage is now referred to as the key in these transitions because it can boost renewable energy use while also improving the efficiency of conventional power plants (Hall and Bain, …


Applying The Efficiency Gap To Wisconsin Politics, Joseph Robert Szydlik May 2023

Applying The Efficiency Gap To Wisconsin Politics, Joseph Robert Szydlik

Theses and Dissertations

Gerrymandering is a plague on modern democracy, blatantly violating the democratic principle of “one person, one vote.” Here we will methodically examine the 2018 Wisconsin state assembly election, and using a metric known as the efficiency gap demonstrate the extent to which gerrymandering played a role. Through this metric, and a probabilistic simulation of our own, we will show that in this election the Republican party benefited from systematic partisan gerrymandering. Additionally, we will use these findings to suggest methods for correcting this undemocratic practice that both parties utilize in order to disenfranchise opposition voters.


Baseball’S Evolution In The 21st Century, And How It Exemplifies Human Response To Change, Jonathan Sharpe May 2023

Baseball’S Evolution In The 21st Century, And How It Exemplifies Human Response To Change, Jonathan Sharpe

Honors Projects

The game of baseball has changed a lot in the past twenty years. It can be primarily attributed to the explosion in data analytics and how they are used to evaluate baseball players. This led to different player profiles being preferred and eventually led to the development of players changing. As a result, the strategies employed have also evolved and turned into a different game than seen only a couple of decades ago. This paper will explore the changes that the game has seen. On the other hand, Major League Baseball has also implemented its own changes to try and …


Fully Decoupled Energy-Stable Numerical Schemes For Two-Phase Coupled Porous Media And Free Flow With Different Densities And Viscosities, Yali Gao, Xiaoming He, Tao Lin, Yanping Lin May 2023

Fully Decoupled Energy-Stable Numerical Schemes For Two-Phase Coupled Porous Media And Free Flow With Different Densities And Viscosities, Yali Gao, Xiaoming He, Tao Lin, Yanping Lin

Mathematics and Statistics Faculty Research & Creative Works

In this article, we consider a phase field model with different densities and viscosities for the coupled two-phase porous media flow and two-phase free flow, as well as the corresponding numerical simulation. This model consists of three parts: a Cahn-Hilliard-Darcy system with different densities/viscosities describing the porous media flow in matrix, a Cahn-illiard-Navier-Stokes system with different densities/viscosities describing the free fluid in conduit, and seven interface conditions coupling the flows in the matrix and the conduit. Based on the separate Cahn-Hilliard equations in the porous media region and the free flow region, a weak formulation is proposed to incorporate the …


Identifying And Analyzing Multi-Star Systems Among Tess Planetary Candidates Using Gaia, Katie E. Bailey May 2023

Identifying And Analyzing Multi-Star Systems Among Tess Planetary Candidates Using Gaia, Katie E. Bailey

Electronic Theses and Dissertations

Exoplanets represent a young, rapidly advancing subfield of astrophysics where much is still unknown. It is therefore important to analyze trends among their parameters to learn more about these systems. More complexity is added to these systems with the presence of additional stellar companions. To study these complex systems, one can employ programming languages such as Python to parse databases such as those constructed by TESS and Gaia to bridge the gap between exoplanets and stellar companions. Data can then be analyzed for trends in these multi-star exoplanet systems and in juxtaposition to their single-star counterparts. This research was able …


College Of Natural Sciences Newsletter, March - May 2023, College Of Natural Sciences May 2023

College Of Natural Sciences Newsletter, March - May 2023, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 4, Issue 2

Page 1 Dean's Message
Page 2-7 Awards and Recognition
Page 8 March 3rd Corothers Seminar
Page 9 54th Geography Convention
Page 10 Spring 2023 Day of Scholars
Page 11 2023 URSCAD Snaps
Page 12-14 Media Coverage of CNS
Page 15 Open PRAIRIE Data


Why Inverse Layers In Pavement? Why Zipper Fracking? Why Interleaving In Education? A General Explanation, Edgar Daniel Rodriguez Velasquez, Aaron Velasco, Olga Kosheleva, Vladik Kreinovich May 2023

Why Inverse Layers In Pavement? Why Zipper Fracking? Why Interleaving In Education? A General Explanation, Edgar Daniel Rodriguez Velasquez, Aaron Velasco, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

In many practical situations, if we split our efforts into two disconnected chunks, we get better results: a pavement is stronger if instead of a single strengthening layer, we place two parts of this layer separated by no-so-strong layers; teaching is more effective if instead of concentrating a topic in a single time interval, we split it into two parts separated in time, etc. In this paper, we provide a general explanation for all these phenomena.


Fast -- Asymptotically Optimal -- Methods For Determining The Optimal Number Of Features, Saied Tizpaz-Niari, Luc Longpré, Olga Kosheleva, Vladik Kreinovich May 2023

Fast -- Asymptotically Optimal -- Methods For Determining The Optimal Number Of Features, Saied Tizpaz-Niari, Luc Longpré, Olga Kosheleva, Vladik Kreinovich

Departmental Technical Reports (CS)

In machine learning -- and in data processing in general -- it is very important to select the proper number of features. If we select too few, we miss important information and do not get good results, but if we select too many, this will include many irrelevant ones that only bring noise and thus again worsen the results. The usual method of selecting the proper number of features is to add features one by one until the quality stops improving and starts deteriorating again. This method works, but it often takes too much time. In this paper, we propose …


Comparison Of Different Robust Methods In Linear Regression And Applications In Cardiovascular Data, Jagannath Das May 2023

Comparison Of Different Robust Methods In Linear Regression And Applications In Cardiovascular Data, Jagannath Das

Open Access Theses & Dissertations

Due to advanced technology and wide source of data collection, high-dimensional data is available in several fields, including healthcare, bioinformatics, medicine, epidemiology, economics, finance, sociology, and climatology. In those datasets, outliers are generally encountered due to technical errors, heterogeneous sources, or the effect of some confounding variables. As outliers are often difficult to detect in high-dimensional data, the standard approaches may fail to model such data and produce misleading information. In this thesis, we studied Huber and Tukey's M-estimators for linear regression that automatically down-weight outliers and provide a good fit. We also investigated two variable selection methods -- LASSO …


Analysis Of The Electrostatic Characteristics Of The Zika Virus Capsid Using Computational Methods, Cassandra Guadalupe Del Rio De Avila May 2023

Analysis Of The Electrostatic Characteristics Of The Zika Virus Capsid Using Computational Methods, Cassandra Guadalupe Del Rio De Avila

Open Access Theses & Dissertations

Zika virus (ZIKV) is a flavivirus that is usually transmitted through the bite of infected mosquitoes. This virus can cause a variety of neurological disorders, the most common being Guillain-Barré syndrome in adults. Moreover, it is of great concern in pregnant women, since can cause deformities in the brain and other organs of newborns.Studying the structural characteristics of the virus during its mature and infectious phase can provide crucial information on the mechanisms by which it enters and replicates within host cells, as well as its evolution, transmission, and interaction with other living organisms. The symmetric pattern present in the …


Nonparametric Estimation Of Elliptical Copulas, Panfeng Liang May 2023

Nonparametric Estimation Of Elliptical Copulas, Panfeng Liang

Open Access Theses & Dissertations

Elliptical copulas provide flexibility in modeling the dependence structure of a random vector. They are often parameterized with a correlation matrix and a scalar function, called generator. The estimation of the generator can be challenging, because it is a functional parameter. In this dissertation, we provide a rigorous approach to estimating the generator in a Bayesian framework, which is simpler, more robust, and outperforms existing estimation methods in the literature. Based on the proposed framework in this dissertation, other researchers may modify the model for other types of generators in their own research.


Temporal Trends In Dryland Soil Carbon Fluxes In Response To Artificial And Natural Pulsed Moisture Events, Briana Alyce Salcido May 2023

Temporal Trends In Dryland Soil Carbon Fluxes In Response To Artificial And Natural Pulsed Moisture Events, Briana Alyce Salcido

Open Access Theses & Dissertations

Critical zone processes in drylands play a crucial role in the global carbon cycle, and one of the most important processes is soil CO2 efflux at the interface between soils and the atmosphere, which represents a main pathway for loss of carbon. Predicting the carbon dynamics at this interface is challenging due to the complexity of belowground processes, which include both biotic (soil respiration) and abiotic (calcite precipitation) production of CO2, as well as transport processes that include both diffusive and advective components. In this study, we aimed to investigate the contribution of soil air displacement to soil CO2 efflux …


Detecting Complex Cyber Attacks Using Decoys With Online Reinforcement Learning, Marcus Gutierrez May 2023

Detecting Complex Cyber Attacks Using Decoys With Online Reinforcement Learning, Marcus Gutierrez

Open Access Theses & Dissertations

Most vulnerabilities discovered in cybersecurity can be associated with their own singular piece of software. I investigate complex vulnerabilities, which may require multiple software to be present. These complex vulnerabilities represent 16.6% of all documented vulnerabilities and are more dangerous on average than their simple vulnerability counterparts. In addition to this, because they often require multiple pieces of software to be present, they are harder to identify overall as specific combinations are needed for the vulnerability to appear.

I consider the motivating scenario where an attacker is repeatedly deploying exploits that use complex vulnerabilities into an Airport Wi-Fi. The network …


Sexual Dimorphism Of Glomerular Capillary Morphology In Rats, Zackarias Coker May 2023

Sexual Dimorphism Of Glomerular Capillary Morphology In Rats, Zackarias Coker

Undergraduate Honors Theses

Chronic kidney disease (CKD) progresses faster in males than females; however, the underlying mechanisms remain poorly understood. Sex differences in glomerular capillary morphology has been hypothesized to contribute, in part, to the increased susceptibility to hypertension-induced renal injury and CKD progression in males, but this has not been investigated. The goal of the present study was to assess glomerular capillary morphology in male vs. female rats with intact kidneys and after uninephrectomy (UNX). We hypothesized that glomerular capillary radii (RCAP) and length (LCAP) would be greater in male rats.

Male (n=4) and female (n=4) with intact …


Greenhouse Gas Emission Reduction Plan, Lauren Bruhl, Guinter Vogg, Gabe Hamburg, Shanu Sankara, Rohan Kansagra, Colin Page, Colette Vynerib May 2023

Greenhouse Gas Emission Reduction Plan, Lauren Bruhl, Guinter Vogg, Gabe Hamburg, Shanu Sankara, Rohan Kansagra, Colin Page, Colette Vynerib

Sustainability Exchange

Our team aimed to compile a greenhouse gas inventory for the St. Louis region. Partnered with OneSTL, Ameren, and the USGBC, we determined that St. Louis has a goal to reduce emissions 50% by 2030 from 2005 levels, and become carbon neutral in 2050. After analyzing the Ameren’s Integrated Resource Plan and factors such as the cost and scope of emissions, we researched funding sources to improve energy efficiency and increase renewables in the region. Our top funding sources are the Inflation Reduction Act (IRA) and the Bipartisan Infrastructure Law (BIL). From the IRA, we found the following credits most …


Wustl Campus Zero-Waste Strategy Washu Waste System Assessment & Zero Waste Planning, Carol Ge, Bella Kennebrae, Thalia Phillips, Avi Shah, Charles Wilson May 2023

Wustl Campus Zero-Waste Strategy Washu Waste System Assessment & Zero Waste Planning, Carol Ge, Bella Kennebrae, Thalia Phillips, Avi Shah, Charles Wilson

Sustainability Exchange

WUSTL Campus Zero-Waste Strategy WashU Waste System Assessment & Zero Waste Planning for Sustainability Exchange, Washington University in St. Louis, Spring 2023


Change Point Detection For A Process Having Several Regimes, Oliver Gerd Meister May 2023

Change Point Detection For A Process Having Several Regimes, Oliver Gerd Meister

Theses and Dissertations

In this dissertation, possible methods for multiple change point detection on Markovchain processes are studied. Related works for oine and online change point detection are discussed and their applicability on sequential multiple change point detection for several regimes is evaluated. We develop a method for a multiple change point detection for a process having three regimes. Its eciency is then evaluated on simulated Markov chain data by looking into dierent scenarios such as processes that signicantly dier between each other or probability distributions that are slightly similar. This approach is then applied on Covid- 19 hospital data. Therefore, the data …


Analyzing And Computing Complete Solution For Dots And Boxes Game, Carl Mcaninch May 2023

Analyzing And Computing Complete Solution For Dots And Boxes Game, Carl Mcaninch

Graduate Dissertations and Theses

This thesis improves a process that analyzes all the states of a game of Dots and Boxes. We use retrograde analysis and simulations to create a solution that provides significant performance improvements over our previous best solution. Expanding upon a previous 4x4 solution using rotations, reflections, better optimization, and cloud computing to limit the processing time and gather more data efficiently. We compute a file and the number of states associated with each file and process every state starting with a completely filled board. We optimized the data for cloud computing by running simulations to find the most efficient number …


Internet Programming, Kwame A. Baffour May 2023

Internet Programming, Kwame A. Baffour

Open Educational Resources

CSC 31800 – Internet Programming

The design and implementation of websites from a Human-Computer Interaction point of view. Covers client-side technologies such as HTML, CSS and JavaScript and server-side technologies including Node.js and relational databases. Responsiveness, inclusion and accessibility by persons with mobility and vision impairment is necessary and must be addressed in the final project.



Fair Enough: Standardizing Evaluation And Model Selection For Fairness Research In Nlp, Xudong Han, Timothy Baldwin, Trevor Cohn May 2023

Fair Enough: Standardizing Evaluation And Model Selection For Fairness Research In Nlp, Xudong Han, Timothy Baldwin, Trevor Cohn

Natural Language Processing Faculty Publications

Modern NLP systems exhibit a range of biases, which a growing literature on model debiasing attempts to correct. However, current progress is hampered by a plurality of definitions of bias, means of quantification, and oftentimes vague relation between debiasing algorithms and theoretical measures of bias. This paper seeks to clarify the current situation and plot a course for meaningful progress in fair learning, with two key contributions: (1) making clear inter-relations among the current gamut of methods, and their relation to fairness theory; and (2) addressing the practical problem of model selection, which involves a trade-off between fairness and accuracy …