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Full-Text Articles in Physical Sciences and Mathematics

Attenuated Skeletal Muscle Metabolism Explains Blunted Reactive Hyperemia After Prolonged Sitting, Cody Anderson, Elizabeth Pekas, Michael Allen, Song-Young Park Mar 2023

Attenuated Skeletal Muscle Metabolism Explains Blunted Reactive Hyperemia After Prolonged Sitting, Cody Anderson, Elizabeth Pekas, Michael Allen, Song-Young Park

UNO Student Research and Creative Activity Fair

Introduction: Although reduced post-occlusive reactive hyperemia (PORH) after prolonged sitting (PS) has been reported as impaired microvascular function, no specific mechanism(s) have been elucidated. One potential mechanism, independent of microvascular function, is that an altered muscle metabolic rate (MMR) may change the magnitude of PORH by modifying the oxygen deficit achieved during cuff-induced arterial occlusions. We speculated that if MMR changes during PS, this may invalidate current inferences about microvascular function during PS. Objective: Therefore, the objective of this study was to examine if peripheral leg MMR changes during PS and to ascertain whether the change in the oxygen deficit …


Problem Of The Week: A Student-Led Initiative To Bring Mathematics To A Broader Audience, Jordan M. Sahs, Brad Horner Mar 2023

Problem Of The Week: A Student-Led Initiative To Bring Mathematics To A Broader Audience, Jordan M. Sahs, Brad Horner

UNO Student Research and Creative Activity Fair

Problem of the Week (POW!) is a weekly undergraduate mathematics competition hosted by two graduate students from the UNO Math Department. It started with the goal to showcase variety, creativity, and intrigue in math to those who normally feel math is dry, rote, and formulaic. Problems shine light on both hidden gems and popular recreational math, both math history and contemporary research, both iconic topics and nontraditional ones, both pure abstraction and real-world application. Now POW! aims to increase availability and visibility in Omaha and beyond. Select problems from Fall 2021 to Spring 2023 are highlighted here: these received noteworthy …


Healthcare Facilities: Maintaining Accessibility While Implementing Security, Ryan Vilter Mar 2023

Healthcare Facilities: Maintaining Accessibility While Implementing Security, Ryan Vilter

UNO Student Research and Creative Activity Fair

In the wake of the Tulsa, Oklahoma hospital shooting in the summer of 2022, it was made clear that more security needed to be implemented in healthcare facilities. As a result, I inquired: What is the happy balance for healthcare facilities to maintain their accessibility to the public while also implementing security measures to prevent terrorist attacks? With that base, I give recommendations in the areas of cybersecurity, physical infrastructure, and physical and mental health, based off the existing literature and data gathered from terrorist attacks against hospitals over several decades.


The Effects Of Demographics And Risk Factors On The Morphological Characteristics Of Human Femoropopliteal Arteries, Sayed Ahmadreza Razian, Majid Jadidi, Alexey Kamenskiy Mar 2023

The Effects Of Demographics And Risk Factors On The Morphological Characteristics Of Human Femoropopliteal Arteries, Sayed Ahmadreza Razian, Majid Jadidi, Alexey Kamenskiy

UNO Student Research and Creative Activity Fair

Background: Disease of the lower extremity arteries (Peripheral Arterial Disease, PAD) is associated with high morbidity and mortality. During disease development, the arteries adapt by changing their diameter, wall thickness, and residual deformations, but the effects of demographics and risk factors on this process are not clear.

Methods: Superficial femoral arteries from 736 subjects (505 male, 231 female, 12 to 99 years old, average age 51±17.8 years) and the associated demographic and risk factor variables were used to construct machine learning (ML) regression models that predicted morphological characteristics (diameter, wall thickness, and longitudinal opening angle resulting from the …


Time Evolution Is A Source Of Bias In The Wolf Algorithm For Largest Lyapunov Exponents, Kolby Brink, Tyler Wiles, Nicholas Stergiou, Aaron Likens Mar 2023

Time Evolution Is A Source Of Bias In The Wolf Algorithm For Largest Lyapunov Exponents, Kolby Brink, Tyler Wiles, Nicholas Stergiou, Aaron Likens

UNO Student Research and Creative Activity Fair

Human movement is inherently variable by nature. One of the most common analytical tools for assessing movement variability is the largest Lyapunov exponent (LyE) which quantifies the rate of trajectory divergence or convergence in an n-dimensional state space. One popular method for assessing LyE is the Wolf algorithm. Many studies have investigated how Wolf’s calculation of the LyE changes due to sampling frequency, filtering, data normalization, and stride normalization. However, a surprisingly understudied parameter needed for LyE computation is evolution time. The purpose of this study is to investigate how the LyE changes as a function of evolution time …


Using Graph Theoretical Methods And Traceroute To Visually Represent Hidden Networks, Jordan M. Sahs Jun 2022

Using Graph Theoretical Methods And Traceroute To Visually Represent Hidden Networks, Jordan M. Sahs

UNO Student Research and Creative Activity Fair

Within the scope of a Wide Area Network (WAN), a large geographical communication network in which a collection of networking devices communicate data to each other, an example being the spanning communication network, known as the Internet, around continents. Within WANs exists a collection of Routers that transfer network packets to other devices. An issue pertinent to WANs is their immeasurable size and density, as we are not sure of the amount, or the scope, of all the devices that exists within the network. By tracing the routes and transits of data that traverses within the WAN, we can identify …


Unomaha Problem Of The Week (2021-2022 Edition), Brad Horner, Jordan M. Sahs Jun 2022

Unomaha Problem Of The Week (2021-2022 Edition), Brad Horner, Jordan M. Sahs

UNO Student Research and Creative Activity Fair

The University of Omaha math department's Problem of the Week was taken over in Fall 2019 from faculty by the authors. The structure: each semester (Fall and Spring), three problems are given per week for twelve weeks, with each problem worth ten points - mimicking the structure of arguably the most well-regarded university math competition around, the Putnam Competition, with prizes awarded to top-scorers at semester's end. The weekly competition was halted midway through Spring 2020 due to COVID-19, but relaunched again in Fall 2021, with massive changes.

Now there are three difficulty tiers to POW problems, roughly corresponding to …


Reducing Loading On The Contralateral Limb Using Human-In-The-Loop Optimization, Siena Senatore Mar 2022

Reducing Loading On The Contralateral Limb Using Human-In-The-Loop Optimization, Siena Senatore

UNO Student Research and Creative Activity Fair

In most everyday activities, we head towards a specific goal by updating our choices for a more direct path. However, there are specific clinical tasks where taking the direct path is more challenging. Clinical investigations of optimizing a prosthesis involve the assessment of multiple parameter settings through trial and error rather than goal-directed optimization. We investigate if a human-in-the-loop optimization algorithm can guide manual alterations to a prosthesis-simulating device to reduce the ground reaction force on the contralateral limb. In most participants, the optimal condition reduced the loading rate on the contralateral limb compared to the initial condition tested. These …


Design And Development Of Software With A Graphical User Interface To Display And Convert Multiple Microscopic Histology Images, Sayed Ahmadreza Razian, Majid Jadidi, Alexey Kamenskiy Mar 2022

Design And Development Of Software With A Graphical User Interface To Display And Convert Multiple Microscopic Histology Images, Sayed Ahmadreza Razian, Majid Jadidi, Alexey Kamenskiy

UNO Student Research and Creative Activity Fair

Histological images are widely used to assess the microscopic anatomy of biological tissues. Recent advancements in image analysis allow the identification of structural features on histological sections that can help advance medical device development, brain and cancer research, drug discovery, vascular mechanobiology, and many other fields. Histological slide scanners create images in SVS and TIFF formats that were designed to archive image blocks and high-resolution textual information. Because these formats were primarily intended for storage, they are often not compatible with conventional image analysis software and require conversion before they can be used in research. We have developed a user-friendly …


Team Coordination Dynamics Of Winning Nba Teams, Alli Grunkemeyer, Joel H. Sommerfeld Mar 2022

Team Coordination Dynamics Of Winning Nba Teams, Alli Grunkemeyer, Joel H. Sommerfeld

UNO Student Research and Creative Activity Fair

Predicting sports games outcomes is an endless pursuit shared by stakeholders ranging from fans to coaches to data scientists. We have begun investigating the value of positional data recorded during basketball gameplay with the goal of predicting outcomes from team dynamics as they emerge. We approached this problem by analyzing the “shape” of team movements on the court and investigated whether team dynamics in NBA games mimicked long-range correlated patterns observed in other team contexts. We analyzed 622 NBA games from an archival data set, including all area time series obtained for each of the four quarters. We fit a …


Ingredient Classification Using Food Ontology, Ricky Flores Mar 2022

Ingredient Classification Using Food Ontology, Ricky Flores

UNO Student Research and Creative Activity Fair

A food label provides some of the most crucial information for a food product. The food label is a key resource for many health-conscious consumers for understanding ingredients. It is also vital for individuals to avoid food allergens or help patients follow dietary recommendations. While the food labels in the United States are regulated by the Food and Drug Administration (FDA) many labels contain additional information or statements that are not regulated. Moreover, the food label may be complex or contain terminology that the layperson may not understand. Evidence has indicated that consumers often find nutrition labels confusing, especially when …


Optimizing Networking Topologies With Shortest Path Algorithms, Jordan Sahs Mar 2021

Optimizing Networking Topologies With Shortest Path Algorithms, Jordan Sahs

UNO Student Research and Creative Activity Fair

Communication networks tend to contain redundant devices and mediums of transmission, thus the need to locate, document, and optimize networks is increasingly becoming necessary. However, many people do not know where to start the optimization progress. What is network topology? What is this “Shortest Path Problem”, and how can it be used to better my network? These questions are presented, taught, and answered within this paper. To supplement the reader’s understanding there are thirty-eight figures in the paper that are used to help convey and compartmentalize the learning process needed to grasp the materials presented in the ending sections.

In …


Remotely Controlled Enzyme Behavior Using Localized Thermal Gradients, Sarah Brown Mar 2021

Remotely Controlled Enzyme Behavior Using Localized Thermal Gradients, Sarah Brown

UNO Student Research and Creative Activity Fair

No existing model describes an identified special case of enzyme behavior when directly stimulated with thermal energy via an RF field.

The ability to remotely influence cellular functions and outcomes is a new approach to targeted medicine. Nano-medicine and biotechnology are the future of medical diagnostics and treatment. The ability to remotely influence cellular functions and outcomes is a new approach to targeted medicine. Direct heating of an enzyme vs bulk heating changes the enzyme activity.

I tested how direct transfer of thermal energy changes rates of enzyme reactions. We created samples of enzymes, attached to ferrous (magnetic) nano-particles, and …


Determination Of Atrazine In Glacier Creek Using Gas Chromatography-Mass Spectrometry, Spencer Witte Mar 2021

Determination Of Atrazine In Glacier Creek Using Gas Chromatography-Mass Spectrometry, Spencer Witte

UNO Student Research and Creative Activity Fair

Atrazine is a commonly used herbicide in agriculture that has been shown to cause adverse health-effects on biological organisms. Glacier Creek Preserve (GCP), a prairie preserve near Omaha, NE, contains restored prairie and agricultural land uses within a single watershed. Surface water samples were collected at various locations of GCP from May to July to quantify atrazine concentrations. Sample preparation included filtering with a 0.45 micron filter and solid-phase extraction (SPE) with a reversed-phase cartridge. The analyte was eluted off the cartridge with ethyl acetate and analyzed by gas chromatography-mass spectrometry (GC/MS). Quantitation was performed with an internal standard calibration …


Discontinuous Galerkin Method Applied To Navier-Stokes Equations, Ian Deruiter, Mahboub Baccouch Mar 2021

Discontinuous Galerkin Method Applied To Navier-Stokes Equations, Ian Deruiter, Mahboub Baccouch

UNO Student Research and Creative Activity Fair

Discontinuous Galerkin (DG) finite element methods are becoming important techniques for the computational solution of many real-world problems describe by differential equations. They combine many attractive features of the finite element and the finite volume methods. These methods have been successfully applied to many important PDEs arising from a wide range of applications. DG methods are highly accurate numerical methods and have considerable advantages over the classical numerical methods available in the literature. DG methods can easily handle meshes with hanging nodes, elements of various types and shapes, and local spaces of different orders. Furthermore, DG methods provide accurate and …


Developing A Discrete Event Simulation Model To Overcome Human Trafficking, Sydney Meier Mar 2021

Developing A Discrete Event Simulation Model To Overcome Human Trafficking, Sydney Meier

UNO Student Research and Creative Activity Fair

Human trafficking is a complex issue that affects society and the global economy. This societal problem involves the commercial exchange and exploitation of people through forced labor, domestic servitude, and sex trade. Human trafficking is considered the third most profitable organized crime in the world. By analyzing the flow of monetary gains/resources, information and trafficked people from the perspective of traffickers, police force, and advocacy organizations, this research aims to develop a discrete event simulation model to represent this complex system. The following paper describes the developmental process of acquiring data and creating a base model. While the model is …


Encryption Decrypted, Alex Ramsey Mar 2020

Encryption Decrypted, Alex Ramsey

UNO Student Research and Creative Activity Fair

Encryption is a complex and bewildering process, yet it is absolutely foundational for secure and safe activities on the internet. Encryption, in its many forms, ultimately enables identity verification, password protection, secure conversation, cryptocurrency trade, and other online activities. Despite this widespread use, encryption is not a process easily explained to the layperson due to its complexity. Thus, the object of this research is to demystify the process of encryption and provide an understanding of one of the most common forms of modern encryption - RSA Encryption. This will be accomplished through the information provided on my poster as well …


Automated Tool Support - Repairing Security Bugs In Mobile Applications, Larry Singleton Mar 2020

Automated Tool Support - Repairing Security Bugs In Mobile Applications, Larry Singleton

UNO Student Research and Creative Activity Fair

Cryptography is often a critical component in secure software systems. Cryptographic primitive misuses often cause several vulnerability issues. To secure data and communications in applications, developers often rely on cryptographic algorithms and APIs which provide confidentiality, integrity, and authentication based on solid mathematical foundations. While many advanced crypto algorithms are available to developers, the correct usage of these APIs is challenging. Turning mathematical equations in crypto algorithms into an application is a difficult task. A mistake in cryptographic implementations can subvert the security of the entire system. In this research, we present an automated approach for Finding and Repairing Bugs …


Characterization Of Dimerization Domains On The Mannose-6-Phosphate/Insulin-Like Growth Factor 2 Receptor, Tyler Degener Mar 2020

Characterization Of Dimerization Domains On The Mannose-6-Phosphate/Insulin-Like Growth Factor 2 Receptor, Tyler Degener

UNO Student Research and Creative Activity Fair

The mannose-6-phosphate/insulin-like growth factor 2 (M6P/IGF2) receptor is a transmembrane protein with the ability to sequester growth factors from the extracellular matrix. This behavior links the receptor to tumor suppression. On a structural level, the extracellular portion of the protein is segmented into 15 homologous repeats, which can be divided further into 5 triplet domains, labelled 1-3, 4-6, 7-9, 10-12, and 13-15. Each triplet receptor displays its own unique ligand binding affinity, including the ability to form dimers with triplets on a second M6P/IGF2 receptor. In fact, previous studies indicate that this protein functions optimally when dimerized. Thus, the purpose …


Design, Construction, And Characterization Of A Low-Cost Spectrometer With Interchangeable Parts, Jack Godek Mar 2020

Design, Construction, And Characterization Of A Low-Cost Spectrometer With Interchangeable Parts, Jack Godek

UNO Student Research and Creative Activity Fair

A low-cost spectrometer was designed for the purpose of teaching spectroscopy. The spectrometer can be built by the student and contains interchangeable pieces such as slit width, grating, and lenses. This will allow the student to understand how changing these variables effects resolution. The spectrometer was constructed from PVC pipe, a plastic electrical box, and a USB webcam. The actual resolution of the spectrometer is close to the theoretical value, depending on which lens and grating is used. In addition, an extra piece can be added that allows absorption spectra to be collected. Having the student piece together the spectrometer …


What Is The Most Threatening Disaster To The Continental United States?, Aaron Spomer, Elijah Kaufman, Julisa Prieto-Garcia, Brooke Aschwanden Mar 2020

What Is The Most Threatening Disaster To The Continental United States?, Aaron Spomer, Elijah Kaufman, Julisa Prieto-Garcia, Brooke Aschwanden

UNO Student Research and Creative Activity Fair

Our goal for our project is to fully understand which natural disaster is the most destructive to the United States. We have chosen to compare hurricanes, floods, tornadoes, wildfires, earthquakes, and nor’easters. We have researched the cost of the total damage and repair, how the warning systems have improved over time, the death tolls from each, and also the frequency at which each one occurs. Each group member will research a different disaster impact, and the data will create a comprehensive view of the level of devastation each disaster has. We collected data all the way from the early 1900s …


Heterogeneous Boolean Networks With Two Totalistic Rules, Katherine Toh Mar 2019

Heterogeneous Boolean Networks With Two Totalistic Rules, Katherine Toh

UNO Student Research and Creative Activity Fair

Boolean Networks are being used to analyze models in biology, economics, social sciences, and many other areas. These models simplify the reality by assuming that each element in the network can take on only two possible values, such as ON and OFF. The node evolution is governed by its interaction with other nodes in its neighborhood, which is described mathematically by a Boolean function or rule. For simplicity reasons, many models assume that all nodes follow the same Boolean rule. However, real networks often use more than one Boolean rule and therefore are heterogeneous networks. Heterogeneous networks have not yet …


Lake Sediment Analysis At Heron Haven Nature Center, Erik Lato Mar 2019

Lake Sediment Analysis At Heron Haven Nature Center, Erik Lato

UNO Student Research and Creative Activity Fair

Understanding the chemical composition of a wetland sanctuary lakebed can help us understand how recent developments may have changed the chemical composition. Due to recent dredging by the U.S. Army Corps of Engineers and previous research on water composition at Heron Haven, the goal of this project was to determine the chemical composition as a function of sediment depth. The concentration of seven different metals and nutrients were analyzed in terms of depth. The aluminum, iron, and phosphate concentrations had no real discernible concentration change as a function of depth. There is some hint of a steady increase of manganese …


Fourier Series Expansion Methods For The Heat And Wave Equations In Two And Three Dimensions On Spherical Domains, Matthew Eller Mar 2019

Fourier Series Expansion Methods For The Heat And Wave Equations In Two And Three Dimensions On Spherical Domains, Matthew Eller

UNO Student Research and Creative Activity Fair

Description: The Fourier series expansion method is an invaluable approach to solving partial differential equations, including the heat and wave equations. For homogeneous heat and wave equations, the solution can readily be found through separation of variables and then expansion of the solution in terms of the eigenfunctions. Solutions to inhomogeneous heat and wave equations through Fourier series expansion methods were not readily available in the literature for two- and three-dimensional cases. In my previous paper, I developed an approach for solving inhomogeneous heat and wave equations on cubic domains using Fourier series expansion methods. I shall extend my …


Investigating Daily Variation In Lotic Prairie Ecosystems, Dominick Caniglia Mar 2019

Investigating Daily Variation In Lotic Prairie Ecosystems, Dominick Caniglia

UNO Student Research and Creative Activity Fair

The goal of this project is to investigate the hydrochemistry of the prairie stream system at Glacier Creek Preserve, namely to determine the chemical behavior as it varies over time. Past sampling revealed annual/seasonal trends, which prompted this study investigating possible changes over the course of a day. To accomplish this, water samples were taken hourly for a twelve hour period in September and November 2018, and were analyzed at the Durham Science Center. All samples were obtained at the furthest downstream site available. The main focus was to study alkalinity and dissolved mineral content. Preliminary data suggests that alkalinity …


The Effect Of Arm Swing On Countermovement Vertical Jump Performance, Arash Mohammadzadeh Gonabadi Mar 2019

The Effect Of Arm Swing On Countermovement Vertical Jump Performance, Arash Mohammadzadeh Gonabadi

UNO Student Research and Creative Activity Fair

Vertical jumping is one of the popular ways to evaluate ankle-knee efficiency in athletic population. Arm swing can play a crucial role in enhancing vertical jump performance. This study aimed to address the differences in kinetic and kinematic parameters during countermovement jump motion with arm swing (AS) and no arm swing (NAS). We used OpenSim to examine the efficacy of AS in reducing the impulse applied to the body and changes in range of lower limb joint angles at landing instant. We calculated the maximum vertical peak of the ground reaction force and impulse generated at landing in two different …


Design For Safety: Decreasing First Responder Health Risks Through Real-Time Bio-Sensor Alerts, Suzy Fendrick Mar 2019

Design For Safety: Decreasing First Responder Health Risks Through Real-Time Bio-Sensor Alerts, Suzy Fendrick

UNO Student Research and Creative Activity Fair

The focus of this research project is using the Design Thinking process to create an informative dashboard for first responders. Design Thinking involves empathizing with the user, defining the problems to be solved, ideation, creating prototypes, and testing. This iterate process focuses on the user, resulting in the most effective product possible. The dashboard will display real-time biosensor data from sensors in the first responders’ uniforms. This project is part of a larger project with the goal of vastly improving the safety of first responders during emergency hazardous material incidents.


Evaluating An Electronic Protocol In A Pediatric Intensive Care Unit, Jeanette Rose Mar 2019

Evaluating An Electronic Protocol In A Pediatric Intensive Care Unit, Jeanette Rose

UNO Student Research and Creative Activity Fair

A team of clinicians at Children’s Hospital and Medical Center (CHMC) developed a standardized protocol in 2018 for the care of patients needing sedation. This protocol is ordered through the EPIC electronic health record system for patients in the pediatric intensive care unit (PICU). When used, electronic protocols reduce the variation in clinical decision making which can ultimately improve patient outcomes. The goal of this project is to evaluate this technology, how the protocol is being used, and how it may be improved. Actual users of the EPIC sedation protocol were the subjects of this study, including PICU physicians, physician …


Estimating Variations In Metabolic Cost Within The Stride Cycle During Level And Uphill Walking, Arash Mohammadzadeh Gonabadi Mar 2019

Estimating Variations In Metabolic Cost Within The Stride Cycle During Level And Uphill Walking, Arash Mohammadzadeh Gonabadi

UNO Student Research and Creative Activity Fair

Indirect calorimetry provides the average cost of a stride cycle and prevents from identifying which part of the gait cycle causes increased metabolic cost in patients, however, recent simulation methods allow estimating the time profile of metabolic cost within the stride cycle. In this study, we compare the estimations of the time profile of the metabolic cost of two simulation methods for level and uphill walking. We used kinematic, kinetic and electromyography data from level and uphill walking (one participant) to estimate the time profiles of metabolic cost using the muscle-level metabolic model of Umberger using electromyography and kinematic data …


Forensics Analysis For Bone Pair Matching Using Bipartite Graphs In Commingled Remains, Ryan Ernst Mar 2019

Forensics Analysis For Bone Pair Matching Using Bipartite Graphs In Commingled Remains, Ryan Ernst

UNO Student Research and Creative Activity Fair

Identification of missing prisoners of war is a complex and time consuming task. There are many missing soldiers whose remains have yet to be returned to their families and loved ones. This nation has a solemn obligation to its soldiers and their families who have made the ultimate sacrifice for their country. There are currently over 82,000 unidentified prisoners of war which are identified at a rate of 100+ per year. At this rate it would take 300+ years to complete the identification process. Previously, anthropologists used excel spreadsheets to sort through skeletal data. This project aims to streamline the …