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Full-Text Articles in Engineering

The Effect Of A Constitutive Formulation On Limb Flexion-Induced Stresses In The Human Femoropopliteal Artery: A Patient-Specific Study, Ali Ahmadi, Anastasia Desyatova Mar 2024

The Effect Of A Constitutive Formulation On Limb Flexion-Induced Stresses In The Human Femoropopliteal Artery: A Patient-Specific Study, Ali Ahmadi, Anastasia Desyatova

UNO Student Research and Creative Activity Fair

The Effect of a Constitutive Formulation on Limb Flexion-Induced Stresses in the Human Femoropopliteal Artery: a Patient-Specific Study

Peripheral arterial disease (PAD) involves the development of atherosclerotic lesions that restrict the flow of blood to tissues downstream. The femoropopliteal artery (FPA) experiences complex mechanical deformations during daily activities, potentially contributing to the prevalence of PAD and unfavorable treatment outcomes. These deformations generate significant intramural stresses and strains, resulting in arterial injury, disease progression, and restenosis following treatment. Computational modeling offers a way to improve the repair of the FPA; however, the accuracy of these simulations relies on the selection of …


Histological Evidence For The Therapeutic Effect Of Chitosan Nanofibrous Dressing On Acute Skin Wounds In A Rat Model, Mahboubeh Ghanbari, Sayed Ahmadreza Razian, Sara Cartwright, Yury Salkovskiy, Jason Mactaggart, Mark A. Carlson Mar 2023

Histological Evidence For The Therapeutic Effect Of Chitosan Nanofibrous Dressing On Acute Skin Wounds In A Rat Model, Mahboubeh Ghanbari, Sayed Ahmadreza Razian, Sara Cartwright, Yury Salkovskiy, Jason Mactaggart, Mark A. Carlson

UNO Student Research and Creative Activity Fair

Introduction: Large-area skin traumas, such as thermal burns, are among the most severe health issues that decrease patients’ quality of life and burden healthcare systems. The CDC estimates that there are 1.1 million burns requiring medical attention each year, with more than 20,000 cases involving at least 25% of the body surface, resulting in 4,500 deaths. In addition, about 10,000 people die from burn-related infections. A promising solution to alleviate this problem is using wound dressings based on biopolymers with inherent wound healing properties and biodegradability. One of these biopolymers is chitosan, which is derived from arthropod shells and exhibits …


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 …


Sustainable Small House Project, Mollie Jo George Mar 2023

Sustainable Small House Project, Mollie Jo George

UNO Student Research and Creative Activity Fair

The Sustainable Small House Project was developed in cooperation with UNO/UNL Engineering, UNO Gerontology, and Metro Community College. This project merges both sustainable living with the small house movement to promote aging-in-place for older adults. This presentation describes the journey of Dr. Bing Chen as he envisioned the Sustainable Small House Project to its development and finally to implementation at its current location--west of Baxter Arena or adjacent to the UNO ballfield.

From a gerontological lens, the project focuses on principles of universal design which allows for aging-in-place, fall-detection and prevention using smart technologies such as Nobi, and voice-activated technologies …


Using Deep Neural Network And Transformers To Extract Graphene Compounds And Properties, Ayman Ibn Jaman Apr 2022

Using Deep Neural Network And Transformers To Extract Graphene Compounds And Properties, Ayman Ibn Jaman

Computer Science Graduate Research Workshop

No abstract provided.


The Optimal Relationship Between Actuator Stiffness And Actuation Timing For A Passive Ankle Exoskeleton: An Opensim Simulation, Cody Anderson, Hafizur Rahman, Sara Myers Mar 2022

The Optimal Relationship Between Actuator Stiffness And Actuation Timing For A Passive Ankle Exoskeleton: An Opensim Simulation, Cody Anderson, Hafizur Rahman, Sara Myers

UNO Student Research and Creative Activity Fair

Introduction

The passive ankle exoskeleton developed by Collins et al. (2015) reduced the metabolic cost of walking with an actuation-timing of ~16% of stance [1]; however, other actuation timings have not been extensively investigated. Therefore, the purpose of this study was to determine the optimal relationship between actuator-stiffness and actuation-timing for a passive ankle exoskeleton by using musculoskeletal modeling.

Methods

Kinematics and ground reaction forces were recorded while a healthy-young male walked on overground force-plates, and these data were exported to a musculoskeletal modeling software (OpenSim) for simulation. A passive ankle exoskeleton model was designed and integrated with a default …


Optimization Of The Musculoskeletal Simulation In Estimation Of Metabolic Cost, Arash Mohammadzadeh Gonabadi, Philippe Malcolm Mar 2022

Optimization Of The Musculoskeletal Simulation In Estimation Of Metabolic Cost, Arash Mohammadzadeh Gonabadi, Philippe Malcolm

UNO Student Research and Creative Activity Fair

Energy from food is supplied to the human body in the form of chemical energy in the muscles. This metabolic energy expenditure is one of the main determinants of the way we walk, and indirect calorimetry measurements are an essential tool for understanding how increases in metabolic cost restrict the mobility of clinical populations. Respiratory oxygen consumption measurements allow recording of the average metabolic cost of walking. However, the time required for these measurements prevents assessing metabolic rate in patients who cannot walk long enough. Musculoskeletal modeling techniques allow to estimate average muscle energy expenditure during locomotion in conjunction with …


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 …


How Can Actuation Timing And Magnitude Of A Bilateral Semi-Rigid Hip Exoskeleton Optimize Metabolic Cost, Arash Mohammadzadeh Gonabadi, Prokopios Antonellis, Sara Myers, Iraklis Pipinos, Philippe Malcolm Mar 2022

How Can Actuation Timing And Magnitude Of A Bilateral Semi-Rigid Hip Exoskeleton Optimize Metabolic Cost, Arash Mohammadzadeh Gonabadi, Prokopios Antonellis, Sara Myers, Iraklis Pipinos, Philippe Malcolm

UNO Student Research and Creative Activity Fair

Semi-rigid exoskeletons could combine some advantages of rigid and soft approaches. The purpose of this study was to investigate the effects of timing and magnitude of assistance from a semi-rigid hip exoskeleton. For ten participants, we tested ten conditions that were combinations of 5 different end-timings, ranging from 21% to 49%, and 2 different moment magnitudes ranging from 0.06 to 0.12 Nm.kg-1. The participants walked in two reference conditions: a condition without actuation and a condition without the exoskeleton. A semi-rigid hip exoskeleton could alter metabolic rate. However, to produce a net assistive effect, it is necessary to …


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 …


Changes In Ankle Muscle Force And Power During Walking In Patients With Peripheral Artery Disease, Hafizur Rahman, Cody Anderson, Iraklis I. Pipinos, Jason M. Johanning, Jianghu Dong, Sara A. Myers Mar 2022

Changes In Ankle Muscle Force And Power During Walking In Patients With Peripheral Artery Disease, Hafizur Rahman, Cody Anderson, Iraklis I. Pipinos, Jason M. Johanning, Jianghu Dong, Sara A. Myers

UNO Student Research and Creative Activity Fair

Background: Patients with peripheral artery disease (PAD) have significantly reduced lower extremity muscle strength compared with healthy individuals as measured during isolated, single plane joint motion by isometric and isokinetic strength dynamometers. The objective of this study was to understand the contribution of the ankle muscles during walking in patients with PAD and compared to healthy older individuals.

Methods: A total of 12 patients diagnosed with Fontaine stage II PAD and 10 healthy older controls were recruited for the study. Each subject walked across a 10-meter pathway with reflective markers placed on specific anatomical locations on lower limbs while the …


Breaks In Longitudinal Elastic Fibers Of Human Femoropopliteal Arteries, Elham Zamani Mar 2022

Breaks In Longitudinal Elastic Fibers Of Human Femoropopliteal Arteries, Elham Zamani

UNO Student Research and Creative Activity Fair

Breaks in Longitudinal Elastic Fibers of Human Femoropopliteal Arteries

Elham Zamani1, Majid Jadidi1

1 Department of Biomechanics, University of Nebraska Omaha, Omaha, NE

Introduction: Elastin is a major protein in the body with half-life >50 years. It is thought that elastic fibers are formed before the postnatal period. In the femoropopliteal artery (FPA), the main artery in the leg, longitudinal elastic fibers are present in External Elastic Lamina (EEL). Our team has studied more than 1000 cadaveric human FPA and has noticed that there are big breaks in their longitudinal elastic fibers in some subjects. Our goal in this work …


Implementation And Evaluation Of A Baseball Pitching Program And Its Impact On Injury Prevention And Performance, Tyler Hamer Mar 2021

Implementation And Evaluation Of A Baseball Pitching Program And Its Impact On Injury Prevention And Performance, Tyler Hamer

UNO Student Research and Creative Activity Fair

The purpose of this study sought to examine the efficacy of biomechanical evaluations on collegiate baseball pitchers. Through this, we seek to develop a model for identifying at-risk athletes through a longitudinal assessment of pitching mechanics spanning pre-season to post-season along with in-season tracking of pathomechanics.


Heterogeneous Resources Cost-Aware Geo-Distributed Data Analytics, Minmin Zhang Mar 2021

Heterogeneous Resources Cost-Aware Geo-Distributed Data Analytics, Minmin Zhang

UNO Student Research and Creative Activity Fair

Many popular cloud service providers deploy tens of data centers (DCs) around the world to reduce user-perceived latency for better user experiences, in which a large amount of data is generated and stored in a geo-distributed manner. Geo-distributed Data Analytics (GDA) has gained great popularity in meeting the growing demand to mine meaningful and timely knowledge from such highly dispersed data. Since GDA systems require a large data migration between DCs via a wide area network (WAN), many existing works invested significant effort to optimize data transfer strategies to efficiently use limited WAN by considering the network pricing policies on …


Design And Development Of A Semi-Rigid Hip Exoskeleton To Reduce Metabolic Cost, Arash Mohammadzadeh Gonabadi, Prokopios Antonellis, Sara Myers, Iraklis Pipinos, Philippe Malcolm Mar 2021

Design And Development Of A Semi-Rigid Hip Exoskeleton To Reduce Metabolic Cost, Arash Mohammadzadeh Gonabadi, Prokopios Antonellis, Sara Myers, Iraklis Pipinos, Philippe Malcolm

UNO Student Research and Creative Activity Fair

Robotic exoskeletons can reduce metabolic cost in healthy individuals and restore mobility in patients with peripheral artery disease (PAD). PAD is a cardiovascular disease produced by atherosclerosis of the leg arteries. The primary symptom of PAD is claudication or pain in the legs during walking, which severely shortens the distance a patient can walk. Knowing that up to 40% of the metabolic cost of walking comes from the hip muscles, different groups have been developing rigid exoskeletons and soft exosuits that assist the hip. Assisting at the hip has the advantage that the exoskeleton mass is positioned close to the …


The Effect Of Walking Speed And Magnitude Of Perturbation On Compensatory Responses, Farahnaz Fallah Tafti, Jenna Yentes Mar 2021

The Effect Of Walking Speed And Magnitude Of Perturbation On Compensatory Responses, Farahnaz Fallah Tafti, Jenna Yentes

UNO Student Research and Creative Activity Fair

Imposing a perturbation can induce an unstable condition during gait. Measuring the compensatory responses may be an accurate indicator of the ability to control stability. Responses to a perturbation can be quantified through the perturbed walking pattern deviations from an unperturbed condition. The aim of this study was to determine the effect of perturbation magnitude or speed of walking on compensatory responses to lateral perturbations during walking. Twenty healthy young participants recruited to this study and they were perturbed with the medium magnitude of perturbation, while walking on the treadmill at three different speeds (slow, preferred, and fast). They also …


Foot Temperature Before And After Walking In Patients With Peripheral Artery Disease, Jose Anguiano-Hernandez Mar 2021

Foot Temperature Before And After Walking In Patients With Peripheral Artery Disease, Jose Anguiano-Hernandez

UNO Student Research and Creative Activity Fair

Peripheral Artery Disease (PAD) is a pathology that can decrease blood flow to the lower limbs, resulting in the inability to regulate body temperature [1]. The effects of impaired blood flow caused by PAD on body temperature are unclear. The purpose of this study is to compare foot temperature changes before and after walking in healthy people and in patients with PAD. We hypothesize that 1) feet affected by PAD will experience a greater increase in temperature than healthy feet during walking and 2) feet affected by PAD will experience a slower rate of temperature recovery after walking compared …


Modeling Spatial Asymmetry In Visuomotor Coordination, Kolby Brink, Aaron Likens, Nikolaos Stergiou Mar 2021

Modeling Spatial Asymmetry In Visuomotor Coordination, Kolby Brink, Aaron Likens, Nikolaos Stergiou

UNO Student Research and Creative Activity Fair

Coordination is foundational to human movement. One prominent model of coordination is the Haken-Kelso-Bunz which predicts change in relative phase between two oscillators during movement. Use of this model has shown that the body has a natural tendency to prefer certain coordination patterns over others. The generalizability of the model has sparked its use throughout the scientific community to observe movement through the lens of dynamical systems theory. We contend that this model can be advanced further through incorporation of visually perceived spatial asymmetries, a component not currently accounted for by the model. That is, we sought to find if …


Development And Testing Of Novel Antimicrobial Materials For Additive Manufacturing With Application In Space, Michael Thompson, Jorge Zuniga, Christopher Copeland, Roberto Saavedra, Claudia Cortes Reyes, Andres Acuña Velásquez, Daniel Martínez Pereira, Claudio Soto Mar 2020

Development And Testing Of Novel Antimicrobial Materials For Additive Manufacturing With Application In Space, Michael Thompson, Jorge Zuniga, Christopher Copeland, Roberto Saavedra, Claudia Cortes Reyes, Andres Acuña Velásquez, Daniel Martínez Pereira, Claudio Soto

UNO Student Research and Creative Activity Fair

PURPOSE: The purpose of the study was twofold: (i) develop and test the antimicrobial properties of a polylactic acid- and a polyurethane-based filament, and (ii) use these filaments to manufacture a socket-based prosthesis to verify printability and longevity of the antimicrobial properties. It was hypothesized that the formulation of a novel biocidal copper-based nanocomposite with a biocompatible 3D printing polymer/copolymer can be used for the development of antimicrobial medical devices to mitigate microbial risks during long space flight missions [1, 2, 3].

METHODS: Polylactic Acid-based Filament Development-The development of a polylactic acid-based filament involved several processes, such as fermentation …


Autocorrelation And Probability Distributions In Gait-Metronome Synchronization, Charles Sloan Mar 2020

Autocorrelation And Probability Distributions In Gait-Metronome Synchronization, Charles Sloan

UNO Student Research and Creative Activity Fair

Recent research has shown that the structure of different pacing signals influences gait dynamics during coordination to those signals. Those studies, however, have not looked at the impact that probability distribution functions play in influencing our gait. This study looks at how both autocorrelation functions and probability distribution has in noisy metronomes to look for sources of synchronization. 10 healthy subjects volunteered to complete this study. The participants were required to wear custom-built glasses with a small screen projected on the lens. The screen showed a visual stimulus that correlated with various signals. The results of the study suggest that …


Effects Of Novel Tool Use: Cortical And Functional Measures In Children Using A Prosthetic Simulator, Chris Copeland Mar 2020

Effects Of Novel Tool Use: Cortical And Functional Measures In Children Using A Prosthetic Simulator, Chris Copeland

UNO Student Research and Creative Activity Fair

As of 2005, there were a total of 1.6 million people living with the loss of a limb, with this population projected to double to 3.6 million by 2050 [1]. While prostheses aim to enhance the function of these individuals, it is estimated that 45% of pediatric prosthetic users reject their prosthesis [2]. The literature which describes the neurological control mechanisms of prosthetic use is sparse and often low-powered due to an inadequate number of participants. However, prosthetic simulators may be a solution to chronically low-powered prosthetic-centric studies by serving as functional homologues, though this has yet to be tested. …


Performance Analysis Of Voting Algorithms In Wireless Sensor Networks, Aditi Mishra Apr 2019

Performance Analysis Of Voting Algorithms In Wireless Sensor Networks, Aditi Mishra

Computer Science Graduate Research Workshop

No abstract provided.


Consensus-Based Robotic Formation Control, Satish Reddy Modugu Apr 2019

Consensus-Based Robotic Formation Control, Satish Reddy Modugu

Computer Science Graduate Research Workshop

No abstract provided.


Simulator For Qubit Measurement Using Augmented Reality, Sai Pradeep Koneti Apr 2019

Simulator For Qubit Measurement Using Augmented Reality, Sai Pradeep Koneti

Computer Science Graduate Research Workshop

No abstract provided.


An Application Of Artificial General Intelligence In Board Games, Nathan Skalka Apr 2019

An Application Of Artificial General Intelligence In Board Games, Nathan Skalka

Computer Science Graduate Research Workshop

No abstract provided.


Developing And Testing Of An Upper Limb Exoskeleton For Stroke Patients, Drew Dudley, David Salazar Mar 2019

Developing And Testing Of An Upper Limb Exoskeleton For Stroke Patients, Drew Dudley, David Salazar

UNO Student Research and Creative Activity Fair

Objective: The main objective of this study was to determine functional and neuromuscular outcomes of stroke patients using their non-preferred hand with and without a 3D printed passive exoskeleton compared to controls using their non-preferred hand with and without the passive exoskeleton. Methods: Adults at least six months post stroke (Stroke, n = 5) and age- and sex- matched healthy controls (Control, n = 5) performed nine trials of a gross motor task while having their brain activity measured. The Fugl-Meyer and “Box and Block” test was used to measure the gross dexterity of the subjects with and without the …


Decreasing Technology Design Costs By Using Youtube Video To Evaluate User Acceptance, Tom Chappelear Mar 2019

Decreasing Technology Design Costs By Using Youtube Video To Evaluate User Acceptance, Tom Chappelear

UNO Student Research and Creative Activity Fair

User acceptance is a measure that contributes to technology feasibility which is a decision point that entrepreneurs use to help make better investment decisions (Hoffer, 2011). User acceptance testing is part of a design strategy where the system designer attempts to minimize risks and provide design information that an entrepreneur can use to make better investment decisions (Hoffer, 2011). A user acceptance testing instruments can range from a low-cost coffeeshop review to expensive lab-based user testing (Shneiderman, 2017). This study builds upon the User Acceptance of Information Technology (UTAUT) model to measure user acceptance for the system being evaluated (Venkatesh, …


Determining The Relationship Between Walking Activity And Inter-Day Patterns In Stroke Survivors, Sydney Andreasen Mar 2019

Determining The Relationship Between Walking Activity And Inter-Day Patterns In Stroke Survivors, Sydney Andreasen

UNO Student Research and Creative Activity Fair

Populations that have suffered from stroke are generally less active than people of otherwise similar demographics and are more susceptible to further health problems, such as another stroke. This study seeks to assess the validity of a treatment that encourages stroke survivors to walk more steps each day, in order to improve their active abilities and become less idle by establishing motivation for activity and therefore, also establishing patterns in the distribution of that activity throughout a stroke survivor’s day. 172 subjects (6 months post-stroke) have participated in a step activity monitoring program to record steps taken using wearable pedometers. …


Intensity And Pattern Of Daily Physical Activity Of Claudicating Patients, Cody Anderson Mar 2019

Intensity And Pattern Of Daily Physical Activity Of Claudicating Patients, Cody Anderson

UNO Student Research and Creative Activity Fair

file:///C:/Users/codya/Desktop/Cody%20et%20al_2019_Human%20Movement%20Variability%20Conference.pdf