Session B: 10:45AM – 12:15PM
Engineering. Session B – Poster Presentations, Ballroom, Union
SESSION B (10:45AM-12:15PM
Location: Ballroom, A. Ray Olpin University Union
Biomarker Discovery with GC-MS
Emily Lym, University of Utah
Faculty Mentor: Swomitra Mohanty, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B1
Tuberculosis (TB) is classified as a global health emergency that primarily appears in developing countries. For people in these countries, traveling to a medical clinic multiple times for diagnosis and treatment is often not feasible. Point-of-care diagnostics are necessary in order to appropriately respond to TB in these often impoverished communities. However, current diagnostic methods, including sputum microscopy, are time consuming and expensive. Notably, TB in children is especially difficult to diagnose and treat. Recent studies have identified several breath-based compounds, including methyl nicotinate, that could potentially serve as biomarkers for Mycobacterium tuberculosis. In an effort to verify and expand on these studies, breath samples from potential TB patients in Uganda have been analyzed using GC-MS techniques, including dual-column verification, standardized tests, and mass spectra interpretation. In a preliminary analysis of the data, we have found evidence supporting the correlation between methyl nicotinate and M. tuberculosis for adult patients but reveals no such relationship in child patients.
Artificial micro-swimming at low Reynolds number
Ruba Alraqibah, University of Utah
Faculty Mentor: Yong Lin Kong, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B2
Recent advances in microrobots have shown great promise for a wide range of biomedical applications with the potential of enabling new aspects of medicine ranging from targeted drug delivery to minimally invasive surgery. However, locomotion represents a significant challenge for robots at the microscale. Swimming at the microscale is challenging due to differences in the fundamental physics between the microscale and macroscale. At the microscale, fluid dynamics are characterized by a low Reynolds number (Re < 0.1) where motions are dominated by viscous forces rather than the inertial forces that dominate macroscale fluid dynamics. In nature, microorganisms have evolved swimming strategies to achieve locomotion in their low Re environment. Extensive development has focused on artificial biomimetic microswimming techniques such as the corkscrew and flexible oar methods. The flexible oar method is advantageous because of its simple design and actuation scheme – consisting of a flexible appendage whose oscillation produces propulsion. Here we explore the flexible oar approach of micro-swimmer designs at low Reynolds number. The work investigates propulsive characteristics of the micro-swimmer by experimentally evaluating the swimming of novel designs in a centimeter-scale setup in high viscosity oil that replicates the low Re environment. Experimental objectives include altering swimmer geometry to enhance locomotion characteristics, such as enabling reconfiguration in confined spaces and simplified actuation schemes, which could enable promising applications and technologies in healthcare. Ultimately, we anticipate that the development of low Re locomotion techniques for microrobots will have a significant impact in the field of medicine by enabling robots to navigate through highly confined and complex regions of the human body to perform medical tasks that address unmet clinical needs.
Applying Statistical Distance Metrics for Dimensionality Reduction
Anna Bell, University of Utah
Faculty Mentor: Jeff Phillips, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B3
At the University of Utah’s Department of Chemistry, the Sigman Lab is searching for “hotspots,” from experiments involving organic compounds and hundreds machine-learning generated descriptors of these compounds. A “hotspot” may be described as densely concentrated target reactions resulting from experimental asymmetric catalysis. In this project, we attempt to identify meaningful 2-dimensional feature spaces containing these hotspots. Using density measures, we score the “clustering” of highly reactive outcomes and their variance from all other outcomes within each pairwise combination of descriptors. The meaningfulness of the score is then determined using a permutation method which calculates whether a hotspot’s distribution differs significantly from the overall distribution of outcomes in its respective 2-dimensional feature space.
Statistical Shape Modeling of Sex-Based Pelvic Morphology
Bergen Braun, University of Utah
Faculty Mentor: Andrew Anderson, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B4
Statistical Shape Modeling of Sex-Based Pelvic Morphology
Bergen Braun, Andrew Anderson, PhD, Penny Atkins, PhD
Hip disease affects many individuals and is detrimental to quality of life. It is generally understood that sex-based differences in hip shape may predispose individuals to certain hip diseases. Specifically, females are more likely to develop acetabular dysplasia, while males are more likely to develop acetabular retroversion and FAI. Further, there is a high prevalence of hip disease related morphology in male and female athletes, especially, acetabular dysplasia and FAI. However, many of these athletes do not have any pain or motion-related symptoms, which indicates that pathological morphology is not well defined. Previously, hip shape and morphology has been evaluated using 2D radiographic measurements, however, the pelvis is a complex shape and cannot be fully represented in 2D. We believe that 3D analysis of the pelvis shape will help us to gain a better insight into shape variation of the pelvis between males and females. Herein, we used 3D statistical shape modeling to determine the variation in male and female pelvis shape for a cohort including patients with hip disease, athletes, and control subjects. The mean male and female pelvic shapes will be used to evaluate the morphological variation of the pelvis and to identify the less obvious anatomical differences between male and female pelvis. Imaging data from fifty-five computed topography (CT) scans and 10 double echo steady state (DESS) magnetic resonance (MR) scans were acquired after obtaining informed consent. The subjects were separated into five cohorts, based on diagnosis or level of activity. These groups included three patient groups based on diagnosis of dysplasia, retroversion or cam FAI, a control group, and a group of collegiate athletes. Each of these groups contained a mix of male and female participants (38 males, 25 females overall). The images were segmented to isolate the pelvic bone based on voxel intensities in the images, using Corview and Amira. Here, all three planes of the images were segmented, and a 3D reconstruction of each pelvis was generated, smoothed, and decimated. The 3D reconstructions of the pelvii were then used to create a statistical shape model using ShapeWorks. ShapeWorks provides methods to automatically place and optimize correspondence particle locations over subject-specific surfaces which provides correspondence across a population of shapes. From the particle locations, the mean shapes were generated for the entire cohort, as well as for all males and females and then for each group. The statistical shape model of the pelvis is still being finalized, but preliminary comparisons between males and females show large shape differences in superolateral iliac crest and posterolateral ischium (Figure 1), which aligns with previously described sex-based differences in pelvic morphology. Results will be finalized within the next few weeks and the analysis expanded to evaluate the five groups.
IMU-based Reconstruction and 3D Visualization of Shoulder Movement
Joey Brignone, University of Utah
Faculty Mentor: Edoardo Battaglia, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B5
Proprioception is the perception of the movement and position of one’s own body [1]. The purpose of this study is to improve the proprioception of the shoulder for stroke patients who have lost this sense. Sensory information that allows proprioception comes from Golgi tendon organs, joint and skin stretch receptors, and muscle spindles [2]. Proprioception deficits in the upper extremity are present in about 30% to 48% of stroke patients [1]. This proposed system in this study will measure shoulder movement through Inertial Measurement Units (IMUs) and visualize the movement in real-time. One of these sensors will be placed on the top of the shoulder and the other will be placed near the top of the upper arm, close to the shoulder. The two sensors contain gyroscopes inside of them to measure the rotation of the arm, as well as accelerometers that measure the force of gravity on the sensor. With the rotation angles and speed as the input, these sensors will determine the position and orientation of the arm. The data from this system will later be transferred from the receiving microcontroller to a haptic device to convey these movements to the patient. Before the device is designed, the position and orientation data of the shoulder will be visualized in a 3D model of a mannequin with the inertial sensors attached using Unity 3D. The accuracy of the model will confirm that the data are correct, and the sensors are appropriately capturing the rotations and speed of the shoulder movement. As many patients who lose this sense are unable to regain complete control over their arms, haptic feedback could allow the user to at least partially restore this sense that was lost. This restoration of proprioception should lead patients to more accurate control over their movements. This system would create practical technology for those whose proprioception has been lost or debilitated, as the system should result in a low-cost solution. Proprioception restoration has been researched most commonly for hand movement, and some additional studies have been done on the lower extremity. Since the shoulder has not been the focus of many upper extremity proprioceptive studies, this will enrich the field of study for those creating an extensive system for aiding proprioception. While this research plan focuses on stroke patients, there are other diseases that cause proprioception loss including multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS)/Lou Gehrig’s disease, joint injuries, Parkinson’s disease, and Huntington’s disease. Medical research is the primary focus of this study, but other robotic applications may be pursued in the future, such as teleoperation or drones.
References:
[1] D. Rand, “Proprioception deficits in chronic stroke-upper extremity function and daily living,” PLOS ONE, vol. 13, no. 3, 2018.
[2] E. Battaglia, J. P. Clark, M. Bianchi, M. G. Catalano, A. Bicchi and M. K. O’Malley, “Skin Stretch Haptic Feedback to Convey Closure Information in Anthropomorphic, Under-Actuated Upper Limb Soft Prostheses,” in IEEE Transactions on Haptics, vol. 12, no. 4, pp. 508-520, 1 Oct.-Dec. 2019, doi: 10.1109/TOH.2019.2915075.
Enabling Entrained Flow Gasification of Blends of Coal, Biomass and Waste Plastic
Natalie Fink, University of Utah
Faculty Mentor: Kevin Whitty, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B6
Gasification has been a successful technology used to convert coal to synthesis gas to produce hydrogen, fuels, and chemicals. The approach of using mixtures of coal, biomass, and plastic in high-pressure, entrain flow gasification (EFG) is a promising method to generate hydrogen through beneficial feedstocks with the potential for net negative carbon dioxide emissions. Despite EFG being a well-researched technology, further investigation is necessary to achieve reliable feed and operation of such mixtures as there are no established means to do so. The objective of this work is to evaluate the feasibility of coal-biomass-plastic slurries for high-pressure EFG. To assess flowability and separation patterns, the mixtures are evaluated for viscosity and phase behavior. A rotational viscometer was used to evaluate viscosity as a function of shear rate and temperature. Shear thinning behavior was apparent in all mixtures with the viscosity being heavily correlated to the coal concentration when above 25 wt%. In addition, viscosity decreased with an increasing shear rate but also with time at a constant shear rate. Increasing plastic oil decreased the viscosity by up to 20%. However, phase separation was present with plastic oil concentrations over 20wt%. Regardless of composition, the viscosity as a function of temperature followed an Arrhenius-type relationship. Thermogravimetric analysis of the blended slurries is used to determine the moisture content, volatiles, and fixed carbon with ash as the residual. Additionally, it is a means to quantify the degree of mixture separation as the composition of separated phases. The favorable mixtures were successfully fed at roughly one ton per day with a progressive cavity pump at pressures greater than 300 psi for four hours. If separation and mixture instability during pumping is prevented, continuous high pressure of coal-biomass-plastic mixtures has been demonstrated.
Association between Preoperative Venous Medial Collagen Fiber Configuration and Arteriovenous Fistula Development
Gabrielle Hadinger, University of Utah
Faculty Mentor: Yan-Ting Shiu, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B7
Background: Arteriovenous fistula (AVF) is the preferred vascular access for hemodialysis but often fails to mature. AVF maturation requires venous dilation to allow increases in blood flow. The required venous dilation is likely affected by its microstructure. We hypothesized that the preoperative collagen fiber configuration index for the venous medial layer may determine venous dilation and hence AVF maturation. Methods: Veins were harvested from 84 kidney failure patients undergoing AVF creation Surgery at the University of Alabama at Birmingham. These vein samples were obtained from near the anastomosis, where the vein and artery were surgically connected. They were formalin fixed, paraffin embedded, and sectioned into 5µm thin sections. The second harmonic generation (SHG) signals in these sections were acquired and analyzed for anisotropy index (AI) and orientation angle (OA). AI ranged from 0 (random fiber network) to 1 (completely aligned fiber network). OA ranged from 0o (parallel to lumen) to 90o (perpendicular to lumen). The fiber configuration index (FCI) was defined as the product of AI and sin(OA). AVF duplex ultrasound was performed post-op at 6weeks. Maturation was defined as the ability for dialysis at blood flow ≥ 300 ml/min for at least 6 dialysis sessions in 1 month and within 6 months post-op. Results: AVF maturation failure occurred in 15.5 % of these patients. The 6-week AVF blood flow was positively associated with the FCI (per 0.1 unit difference in FCI: Δ blood flow = 131 ml/min; 95% CI, 8 to 254 ml/min; p=0.038). The FCI of clinically matured AVFs was significantly higher than that of non-matured AVFs (0.13±0.07 vs. 0.08±0.05, p=0.02). Conclusions: Using the novel fiber configuration index, we have characterized venous medial collagen fiber organization in kidney failure patients. The FCI values appear to be associated with the likelihood of AVF maturation.
Effectiveness of Ski Wax Treatments in Sintered Ski Bases Using Different Temperatures and Application Methods of Ski Wax
Lindi Hopkins, University of Utah
Faculty Mentor: Jeffrey Bates, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B8
This project has focused on application temperatures and methods on sintered ski bases. It is believed that sintered bases have a higher porosity, allowing for better absorption of ski wax. There is a tradeoff with this method as it is more expensive to produce than extruded bases, sintered bases are generally reserved for higher performance skis, such as those used by alpine racers and heavily experienced hobbyists. Ski waxes have been formulated for different conditions of snow primarily cold, warm, and all-temperature waxes. While there has been extensive testing of these waxes’ characteristics, there has not been extensive research on varying application methods and subsequent temperatures. This project delved into application methods and characterization of ski base samples using tribology, hardness, and contact angle testing to obtain data that can be translated into a more effective wax for consumers. Tribology measures the coefficient of friction between the base of the ski and the snow. Results from tribology testing can determine mechanical and thermal stability of the base, this testing could be enhanced by the use of a rheometer that tests coefficient of friction as a function of temperature. Hardness testing, specifically Shore A hardness, tests hardness as a function of temperature which can give insight into how ski wax hardens onto the base. Contact angle can be obtained using the Sessile drop technique, this can help describe the friction factor snow has on sliding velocity, surface roughness, and surface pattern. There are many types of ski wax, recently a large number of brands have stopped producing fluorinated wax as there has been recent environmental concerns revolving around PFOA found in fluorinated waxes. This project utilizes waxes without PFOA to stay relevant with the current transition. In addition, there are many waxing techniques, which can vary from application temperature to the process in base treatment before and after waxing.
The Effects of Transfection on the Differentiation of Stem Cells
Kaylen Lee, University of Utah
Faculty Mentor: Tara Deans, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B9
Novel Genetic Circuit for the Differentiation of Pluripotent Stem Cells into Megakaryocytes. The lineage of all cell types begins with pluripotent stem cells. Pluripotent stem cells may differentiate into hematopoietic stem cells (HSC), which is the start of the blood cell lineage. One of the types of blood cells that derives from HSCs are megakaryocytes (MKs), from which platelets are derived. Platelets are anucleate cells that have important roles in clot formation and inflammation. This makes platelets an ideal vehicle for therapy, as none of the genetic engineering that is done to the precursor stem cells is transmitted to the engineered platelet product. By controlling iPSC differentiation, we can modify MKs to produce engineered platelets. The aim of this project was to design and build a novel genetic circuit that directs mouse embryonic stem (ES) cells to differentiate into megakaryocytes (MKs). The genetic circuit was created by first amplifying the gene for HoxB4, a transcription factor, using PCR. The desired band of the amplified HoxB4 gene was inserted into a DNA vector containing Gata-1 through cloning. The genetic circuit controls the expression of HoxB4 and Gata-1 according to the cell state, allowing control of the cell’s differentiation. The genetic circuit has not been successful, due to incorrect enzyme cutting and failed ligation. Success in the integration of a novel circuit into stem cells would allow for better understanding of how to direct stem cell differentiation, and therefore cell function. This leads to the ability to modify MKs to produce engineered platelets to sense or diagnose thrombosis.
Design of a Low-Profile Arm-Swing Assistance Device
Jesse Prime, University of Utah
Faculty Mentor: Edoardo Battaglia, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B10
Arm movement, specifically swinging, is an integral part of walking and movement for humans. Due to injuries and complex diseases, some people lose their ability to swing their arms correctly or entirely. Incorrect swinging movement or a lack of movement can negatively impact these people’s lives and correlates to a high risk of fall and deteriorated gait patterns. Research has shown that providing assistance to restore the movement of the arms closer to baseline conditions can facilitate better gait recovery. To address this need, a design is proposed of a sleeve-like device that can lift the arm and then release it to mimic the version of the arm-swing movement generated while walking. This would be achieved with a system of cables and pulleys that would be actuated by an electric motor. Additionally, the frequency of the generated arm-swing will be a function of the frequency of the movement of the legs, based on a transfer function relating baseline arm movement to walking patterns obtained from previous research. The design should demonstrate the arm-swing movement at a variety of frequencies while operating on a mannequin. This will display how the device can work at multiple walking speeds to swing an actual arm. Additionally, figures and data will be generated to show the device’s performance and flaws. The data should demonstrate the device’s ability to perform in situations comparable to real-life walking.
A Reliable and Understandable PCB for Underfoot Loading Sensor Array Sampling and Bluetooth Data Transmission
Grange Simpson, University of Utah
Faculty Mentor: Kylee North, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B11
Despite lower extremity fractures being common injuries, little is known about how patient weight-bearing behavior during rehabilitation contributes to long-term outcomes. Monitoring patient weight-bearing behavior using wearable sensors would allow clinicians to develop data-driven rehabilitation protocols. The objective of this study was to categorize gait parameters based on their ability to differentiate between patients with excellent and average long-term outcomes using Fuzzy Inferences System (FIS).Methods: Patients with closed tibial or bimalleolar ankle fractures were recruited in this 3 year observational study. An insole load sensor continuously monitored patient weight-bearing during rehabilitation. Longitudinal data was reduced to 93 gait parameters. Using the 1 yearphysical function outcome score patients were divided into two groups; Excellent Outcomes, and Average Outcomes. A FIS classified gait parameters based on their ability to differentiate between the two outcomes.Results: Of the 42 patients enrolled, 17 had both 1 year physical function outcome score (9 Average, 8 Excellent) and complete insole data (33.7+14.5 y/o, 60% female). The FIS revealed that gait parameters related to step count and active walking time best differentiated the two outcome groups. Weight-bearing magnitude moderately differentiated the two groups, and cadence and static loading variables did not have strong differentiation. All metrics with strong FIS classification had statistically significant two-tailed T-test results (P-value < 0.03), while weak FIS differentiated groups did not.Conclusion: FIS proved to be a powerful tool for automated gait parameter classification due to its ease of implementation, adaptability, and intuitive graphical inputs. Although the data came from a pilot study with small patient size, FIS implementation indicated what gait patterns to focus on when designing higher-powered future clinical trials to produce data-driven protocols.
Timing Cues Enhance Intensity Discrimination at Low Electrocutaneous Frequencies
Rebecca Urban, University of Utah
Faculty Mentor: Jacob George, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B12
The long-term goal of this research is to create a prosthetic hand capable of restoring a sense of touch to users. In the United States alone, 1.2 million people suffer from limb loss [1], [2]. The current standard of care for individuals with limb loss is unsatisfactory; upwards of 50% of individuals abandon their prostheses citing a lack of sensory feedback from the prosthetic hand as a principal reason [3]. Electrocutaneous stimulation of the residual arm nerves can be used to provide sensory feedback to individuals with limb loss. A higher stimulation frequency results in a more intense sensation. We measured the Weber fraction — the minimum percent change in stimulation frequency that can be identified correctly 75% of the time — to describe how well electrocutaneous stimulation can convey the magnitude of tactile stimuli. We previously showed that the Weber fraction is much smaller at lower stimulation frequencies (17% change needed at 50 Hz vs 42% change needed at 100 Hz), which means that electrocutaneous stimulation is more discriminable at lower stimulation frequencies [4]. Here, we show that this enhanced discriminability is due to supplemental temporal cues present at lower frequencies only. When stimulation intensity is decoupled from stimulation frequency, participants were still able to discriminate stimulation frequency at 50 Hz (when there is at least a 30% change) but were not able to discriminate stimulation frequency at 100 Hz. The ability to discriminate stimulation frequency based strictly on temporal cues only at 50 Hz implies that these tactile cues enhance discriminability selectively at lower frequencies. These results help deepen the understanding of the neural basis of tactile perception and can aid the development of sensitized prosthetic hands.
[1] M. P. Fahrenkopf, N. S. Adams, J. P. Kelpin, and V. H. Do, “Hand Amputations,” Eplasty, vol. 18, p. ic21, Sep. 2018.
[2] B. Peerdeman et al., “Myoelectric forearm prostheses: State of the art from a user-centered perspective,” J. Rehabil. Res. Dev., vol. 48, pp. 719-37, Jul. 2011, doi: 10.1682/JRRD.2010.08.0161.
[3] L. Jabban, S. Dupan, D. Zhang, B. Ainsworth, K. Nazarpour, and B. W. Metcalfe, “Sensory Feedback for Upper-Limb Prostheses: Opportunities and Barriers,” IEEE Trans. Neural Syst. Rehabil. Eng., vol. 30, pp. 738-747, 2022, doi: 10.1109/TNSRE.2022.3159186.
[4] A. Citterman, M. Brinton, and J. George, Low Frequencies Improve Intensity Discrimination for Electrocutaneous Artificial Sensory Feedback. 2021. doi: 10.13140/RG.2.2.23554.81602.
A Low-Cost, Multiarticulate, Upper-Limb Exoskeleton
Nathan Wallace, University of Utah
Faculty Mentor: Jacob George, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B13
The long-term goal of this research is to develop a low-cost upper-limb exoskeleton to aid individuals with neuromuscular impairments in underserved communities. About 800,000 people suffer from stroke each year, and up to 80% of them lose mobility or strength of one half of their body, including their arm. Commercial wearable exoskeletons can aid stroke recovery, but the high cost and the limited number of actuated degrees of freedom (DOFs) of these devices prevent widespread use. Here we present the design and development of a low-cost 3D-printed exoskeleton with five actuated DOFs. 3D-printed parts, digital servos, and a low-cost signal processing unit, are used to keep the overall cost below $1,000. The exoskeleton design provides five actuated DOFs, including tripod and power grasps, wrist flexion, wrist pronation/supination, and elbow flexion. In contrast, commercially available exoskeletons provide only two actuated DOFs, tripod grasp and elbow flexion, at a cost of approximately $30,000. This project provides proof of concept that upper-limb exoskeleton devices can be designed to have increased DOFs and a lower price. After further design validation for comfort and torque, this exoskeleton device could treat a variety of neuromuscular deficiencies in underserved communities.
Analysis of the Effects of Moisture on the Electrochemistry of Molten Calcium Chloride
Marah Cragun, Brigham Young University
Rankin Shum, Brigham Young University
Faculty Mentor: Devin Rappleye, Brigham Young University
SESSION B (10:45AM-12:15PM)
POSTER B14
Molten chloride salts have application in carbon capture and utilization, thermal energy storage, solar and nuclear energy production, liquid metal batteries, critical metal (e.g., Mg, Li) production, and other areas. Although these salts have great potential to aid in climate control as well as the long term energy crisis, there is still significant developmental work required within certain applications. One of the main issues with molten chloride salts is that impurities such as oxygen and moisture have a notable impact on the physical qualities of the salt, such as corrosion, melting point, and viscosity. Furthermore, moisture analysis within molten chloride salt systems is an unproven process with little precedent up to this point. This work explores analytical techniques for quantifying the moisture content in molten chloride salts. Electrochemical techniques, such as cyclic voltammetry, square wave voltammetry, and chronoamperometry, are performed to identify and analyze signals relating to hydrogen ions in molten CaCl2. To correlate the hydrogen ion content to electrochemical response, different additions of CaH2 are made within various samples of CaCl2. Electrochemical signals from these experiments are investigated as a possible in-situ method of moisture determination.
The role of environmental factors in the deterioration of electrical properties in conductive nano-composites
Emma Bowden, Brigham Young University
Faculty Mentor: David Fullwood, Brigham Young University
SESSION B (10:45AM-12:15PM)
POSTER B15
Authors: Emma E. Bowden, Jacob D. Carter, Anton E. Bowden, David T. Fullwood. Wearable nanocomposite stretch sensors are an exciting new development in biomechanical motion-tracking technology, with applications in low back pain, knee rehabilitation, fetal movement tracking and other fields. When pulled under a strain (for example when applied to the skin of the lower back and stretched by a patient completing physical therapy exercises), the sensors exhibit a measurable electrical response, which can be used to analyze human motion cheaply and accurately. However, current sensor technologies have exhibited rapid deterioration in the form of increased electrical resistance if left stored in normal room conditions. The purpose of the present work was to evaluate the influence of several proposed environmental factors that could impact the deterioration of electrical properties of these sensors, including temperature, humidity, oxygen exposure, and light exposure. The electromechanical performance of sensors stored under each condition were compared against control sensors over a period of weeks. Our results showed that the presence of oxygen and humidity in the environment where the sensors are stored is the primary cause of the deteriorating electrical properties of the sensors. Sensors that are kept in de-oxygenated or desiccated environments do not deteriorate over time. This understanding allows for long-term storage of the sensors, and assists in gaining a greater understanding of the internal processes at work within the nanoparticle-polymer matrix, particularly as they relate to the interface between conductive particles and the polymer.
Using Focused Ultrasound to activate Shape Memory Alloy
Aldo Chipana, Brigham Young University
Faculty Mentor: Christopher Dillon, Brigham Young University
SESSION B (10:45AM-12:15PM)
POSTER B16
Nitinol is a shape memory alloy that demonstrates ideal characteristics suitable for the Biomedical Engineering Field. The rise in popularity of Nitinol has opened exploration in research for its use in medical procedures. This research will focus mainly on the use of focused and unfocused ultrasound waves commonly used in medical applications in junction with nitinol wire to noninvasively insert inside the human body and heat the wire above the activation energy threshold without causing any damage to the surrounding human tissue. The qualities that Nitinol exhibits are ideal because of its biocompatibility, corrosion resistance, and “shape memory” properties. The challenge that arises while using Nitinol wire has been heating the wire above 46.0 degrees Celsius without causing damage to surrounding human tissue. By incorporating MRgFUS (Magnetic Resonance-guided focused ultrasound surgery) to precisely and noninvasively heat the alloy to above its memory temperature threshold. To show the memory effect of the wire, first it must be strained at room temperature (25 degrees Celsius), wrapped tightly around a rod in a coil shape in order to be inserted into a ballistic gelatin that mimics human tissue. Using the focused ultrasound transducer (with frequencies from 500 kHz to 1.8 MHz) the wire is heated inside of the ballistic gelatin recipient until it returns to its conditioned shape memory state. Thermocouples will measure the temperature of the gelatin to verify that it is within safe temperatures for human tissue. The experiment will run multiple lengths and diameters of Nitinol wire ranging from 1.0mm to 3.0mm for diameter that have activation temperatures between 30-50 degrees Celsius. Additional data will be collected using a commercially available, non-focused ultrasound transducer (frequency range= 1.3 MHz) which generates a more diffused heat region.
Characterizing Temperature-Dependent Tissue Properties for Focused Ultrasound Modeling
Caio Farias, Brigham Young University
Isaac Doddridge, Brigham Young University
Faculty Mentor: Christopher Dillon, Brigham Young University
SESSION B (10:45AM-12:15PM)
POSTER B17
Background: High intensity focused ultrasound (HIFU) is a non-invasive, therapeutic technique used to ablate tumors. HIFU uses concentrated ultrasound waves that are absorbed by human tissue, increasing the local temperature and destroying the tissue. A successful HIFU treatment requires a patient-specific treatment plan that is generated before the therapy by clinicians. Computer modeling can assist clinicians by simulating HIFU treatments and predicting treatment outcomes. However, accurate computer simulations are currently limited due to unknown temperature-dependent properties. An assessment of these properties will make treatments safer and more efficacious. Purpose: Our research aims to experimentally determine temperature-dependent acoustic and thermal properties of porcine muscle tissue for more accurate HIFU simulations. Methods: Thermal properties we investigate include thermal diffusivity [mm2/s], thermal conductivity [W/mK], and specific heat capacity [J/kgK], Acoustic properties include the attenuation coefficient [np/cm], and tissue speed of sound [m/s]. To determine how each property varies with respect to temperature, tissue samples are immersed and allowed to equilibrate in a temperature-controlled water bath prior to measurements. The insertion-loss through-transmission technique is used to calculate the speed of sound and attenuation. Radiation force balance also calculates the tissue’s attenuation coefficient. The thermal properties of each sample are measured with commercially available thermal sensors (METER Group TEMPOS Thermal Property Analyzer and TA Instruments MCDSC) to analyze its change in temperature over time). Preliminary Results: Both acoustic and thermal properties have shown temperature-dependent variation in pork muscle, which has properties similar to human muscle tissue. We have found that attenuation, speed of sound, and specific heat capacity increase as the temperature increases. Current results with the temperature-dependence of thermal conductivity and diffusivity are inconclusive. Conclusion:VThe temperature-dependent thermal and acoustic properties we are measuring have the potential to improve simulations for HIFU treatment plans.
Design of a Thick Origami Flasher for Deployable Optical Space Arrays
Jared Hunter, Brigham Young University
Faculty Mentor: Larry Howell, Brigham Young University
SESSION B (10:45AM-12:15PM)
POSTER 18
Purpose. LiDAR telescopes serve a variety of purposes in the scientific, agricultural, and defense industries. It is desirable for the telescope lens to be large in order to maximize the amount of light collected. However, the satellite must concurrently be compact enough for launch. Origami patterns show promise for application to achieve this duality, but panel thickness and structural stability require special modifications to the origami pattern. The purpose of this research is to determine if thick origami patterns can be used for deployable optical elements in space telescopes. Can an origami-based mechanism be designed to create LiDAR satellites with sufficiently coplanar optical elements and a compact geometry which deploys to a larger diameter?Methodology. The research methodology for this project includes evaluating candidates, selecting an origami pattern, and implementing novel thickness accommodation techniques. The pattern selection process was guided by the work of Bolanos1. Project design constraints suggested the m5-h2-r1 flasher pattern (Figure 1) is the best candidate. The tapered panel thickness accommodation technique is used to overcome the challenges that arise when paper-thin origami patterns are applied to load-bearing mechanical systems. Angled features were placed between adjacent panels to create a coplanar surface (Figure 2). A one-meter prototype was made to validate the design and to test the mechanism’s complex deployment kinematics. Significance. Our optimized origami flasher pattern provides a mode to achieve large deployed-surface-area-to-stowed-volume ratios. The mechanism deploys 0.559 m2 of a thin sheet to a flat state with minor angular deviation (Figure 3). Thick origami mechanisms open the door for small satellites to collect the same amount of light as larger, fixed lens telescopes. Hence, the telescope performance remains constant while the satellite volume and weight are minimized.
1 Bolanos, D., Varela, K., Sargent, B., Stephen, M., Howell, L. L., & Magleby, S. P. (2022). Selecting and optimizing origami flasher pattern configurations for finite-thickness deployable space arrays. Journal of Mechanical Design, 1-11. https://doi.org/10.1115/1.4055900
Interpreting the Clinical Significance of Movement Phenotypes among Patients with cLBP
Tyler Hutchinson, Brigham Young University
Spencer Baker, Brigham Young University
Faculty Mentor: David Fullwood, Brigham Young University
SESSION B (10:45AM-12:15PM)
POSTER 25
Lower back pain (LBP) is a serious condition with a lifetime prevalence as high as 39% . The objective of this study is to identify dominant spinal movement patterns (i.e., phenotypes) among chronic lower back pain (cLBP) patients and interpret their significance for clinical applications. We hypothesize the findings from this study will provide clinicians with important information which will facilitate more personalized treatment paradigms and result in improved efficacy of treatment paradigms. Data were collected from a group of 36 subjects with cLBP using an array of 16 viscoelastic sensors placed on each subject’s lower back to detect skin stretch and spinal motion. Subjects were then instructed to perform 6 repetitions of 14 distinct spinal motions. Data were processed to detect the maximum change of resistance, a feature analogous to spinal range of motion. The subjects were then clustered into phenotypes using a k-means clustering algorithm. The clustering algorithm divided the subjects into 3 phenotype groups for each exercise. These phenotypes were then tested for statistically significant differences among patient-reported outcomes, specifically using Oswestry Disability Index (ODI) scores, using one-way ANOVA and Student T-Tests. This research shows that subjects suffering from cLBP can be clustered into distinct movement phenotypes. Cluster 1 patients demonstrated reduced right lumbar flexion and left lumbar extension ranges of motion (ROM); Cluster 2 demonstrated reduced upper right extension; and Cluster 3 were typified by slightly below average lower right flexion. Subjects in the phenotype clusters 1 and 2 exhibited higher ODI scores than subjects in cluster 3. These observations confirm that cLBP patients have different motion characteristics, and that these differences may result from different sources or mechanisms of cLBP, or from different coping mechanisms, which also influence the patients ODI scores. The study is an important first step to providing clinicians with the tools to improve prescribed treatment paradigms through greater personalization and tailoring.
A Device for the Automated Measurement of Maize Stalk Stiffness and Strength
Jacob Chase, Brigham Young University
Jarom Harris, Brigham Young University
Samuel McKinnon, Brigham Young University
Suzanna Gilbert, Brigham Young University
Faculty Mentor: Ken Hardman, Brigham Young University
SESSION B (10:45AM-12:15PM)
POSTER B20
Modern, high-yielding grain crops can be susceptible to wind-induced failure of the stalk. The development of grain crops that are both high-yielding and structurally robust requires automated testing of stalk strength. Stalk stiffness (flexural rigidity) has been shown to be highly correlated with stalk strength, and thus provides an excellent proxy for strength measurements (which are destructive). Flexural stiffness measurements enable strength to be estimated without causing damage, thus preserving the crop and enabling longitudinal studies. We present a new device that will autonomously collect stalk stiffness data at a rate of 1 second per stalk. Existing devices require manual manipulation and take approximately 24 seconds per stalk, which is much too slow for modern breeding and genetics studies [1]. The new device will displace grain stalks with a load cell; by measuring force and displacement, flexural stiffness can be calculated. The device will be mountable to a vehicle that moves through the field. The automation of these measurements will enable many advances in the structural performance and development of crops. [1] Cook, D. D., de la Chapelle, W., Lin, T.-C., Lee, S. Y., Sun, W., & Robertson, D. J. (2019). Darling: A device for assessing resistance to lodging in grain crops. Plant Methods, 15(1). https://doi.org/10.1186/s13007-019-0488-7
The Effect of Political Orientation on Self-Reported Electric Vehicle Adoption Intent in the United States
Jacob Huff, Utah State University
Faculty Mentor: Antje Graul, Utah State University
SESSION B (10:45AM-12:15PM)
POSTER B21
This study collected representative US data (n=525) to fill the gaps in the existing research on consumer perceptions of light duty electric vehicles (EVs). Research questions regarding what affects consumer EV perceptions and adoption are explored. Specifically, which marketing appeals are most effective at influencing consumer perceptions? What role does charging price and parking convenience play when choosing charging parking spots? What barriers are most influential to potential customers? Is there a difference between owners and non-owners/ other demographics? What are current attitudes, perceptions, and knowledge/ knowledge gaps regarding charging innovations? How can light duty EV adoption be predicted for the next 5, 10, and 15 years? These research questions are intended to fill the gaps in consumer EV research that have yet to address wireless charging, the effects of marketing messaging on EV perceptions, EV preferences, political orientation, and consumers’ perception of the importance of EV characteristics. Prior research hasn’t provided representative samples of the general US population, which this survey has done. This study also integrates novel moderators and mediators to extend prior findings that used closely related constructs.
Selectively Stiffened Integrated Composite Hinge
Philip Klocke, Brigham Young University
Faculty Mentor: Larry Howell, Brigham Young University
SESSION B (10:45AM-12:15PM)
POSTER 22
The purpose of this research is to develop a method to create carbon fiber composites for use in origami-based antennae design through the selective stiffening of carbon fibers. Carbon fiber composites have often been used in manufacturing due to their light weight, yet high stiffness and tensile strength. Typically, this is achieved by reinforcing dry carbon fibers with epoxy, creating stiff, customized, complex surfaces. The use of carbon fiber composites in antenna design is encouraging for the same reasons, though with the added benefit of being non-conductive and antiferromagnetic. In origami-based antennae, a primary drawback of using carbon fiber panels is that their high stiffness makes it difficult to fold without cutting and using rigid body hinges. This research seeks to understand the following question: How can epoxy be selectively applied to dry carbon fibers to create an integrated carbon fiber composite that exhibits both flexibility along hinge lines and stiffness across panel surfaces? Methods produced from this research utilize the flexibility of a dry carbon fiber mesh to create hinges. These hinges have been integrated into the antenna panels by applying epoxy everywhere except along the specified hinge lines of the dry carbon fibers. Two methods have been developed for the selective application of epoxy. In the first method, wax is applied along hinge lines to obstruct the flow of epoxy during compression and curing. The wax is later melted out. In the second method, epoxy is applied and compressed everywhere but along the hinge lines. By using a thin enough layer of epoxy, the epoxy does not flow into the hinge area and only cures in panel locations. Both methods demonstrate the feasibility of using carbon fiber composites in antenna design.
Reducing Uncertainty in Speed of Sound and Attenuation Measurements
Leanna Badger, Brigham Young University
Kaeli Monahan, Brigham Young University
Faculty Mentor: Christopher Dillon, Brigham Young University
SESSION B (10:45AM-12:15PM)
POSTER B23
Background: High-intensity focused ultrasound (HIFU) is a non-invasive treatment that destroys tumors through thermal ablation. Unfortunately, HIFU waves are easily distorted by human anatomy, which causes the focus of the ultrasound to be blurred or misplaced. The tissue properties of speed of sound and attenuation are used to predict where the focus is. By minimizing uncertainty in speed of sound and attenuation measurements, focus predictions will be more accurate and help prevent healthy tissue from being destroyed. Purpose: In our study, we aim to isolate factors that impact speed of sound and attenuation measurements. Experimental factors include sample thickness, sample position, apparatus position, and water quality. Careful evaluation of these factors will help minimize experimental bias and error in HIFU predictions. Through-transmission experiments allow us to find the speed of sound through gelatin samples, which have properties like human tissue. Using an ultrasound transducer and hydrophone, we can measure the time delay in the pressure waves through water and gelatin. The difference in these time delays is used to find the gelatin’s speed of sound and attenuation. Through analyzing which factors affect these property measurements and which do not, we hope to diminish the epistemic uncertainty in HIFU focus predictions. This will ultimately make HIFU more reliable and trusted for clinical applications. Preliminary Results: Initial testing suggests that factors contributing to measurement error consist of movement of the apparatus, the size of the specimen, and variation of gelatin sample composition. Adjusting the distance between the transducer and hydrophone also had an impact on measuring speed of sound. More accurate measurements of the length of each gelatin sample produced more accurate speed of sound results. When comparing multiple measurements in several gelatin samples, speed of sound measurements varied from sample to sample, where some were consistently higher and others lower. This suggests a difference in the material itself, even for samples made from the same gelatin batch. Conclusion: HIFU is a revolutionary, minimally invasive treatment. However, our understanding of acoustic properties that help predict HIFU heating still has a lot of uncertainty. As we reduce variability in our experimental setup, we expect our results to show that uncertainty in acoustic property measurements is dominated by tissue heterogeneity. As error in speeds of sound and attenuation property measurements decrease, we hope that HIFU will become safer due to a decrease in collateral damage caused by this treatment.
Characterizing the Power Spectral Density of Essential Tremor
Noah Francom, Brigham Young University
Faculty Mentor: Steven Charles, Brigham Young University
SESSION B (10:45AM-12:15PM)
POSTER B24
Introduction. Tremor is the most common movement disorder, and current treatment options are not satisfactory to many patients [1,2]. Whether tremor is caused by out-of-phase activity in a pair of antagonist muscles or by rhythmic activity in a single agonist is unknown. To answer this question, we first had to characterize the spectral distribution of tremor power within the tremor band (4-8 Hz). The purpose of our research is to characterize the shape of tremor within the tremor band to better understand the muscle activity that causes tremor using experimental data from Essential Tremor patients. Methods. Surface electromyography (sEMG) signals were recently collected by Pigg et al. from the 15 major superficial muscles of the upper limb in 25 Essential Tremor patients as they held various postures representing common activities [3]. We calculated the power spectral density of each muscle’s sEMG in each posture using Matlab’s pwelch function. From these power spectral densities, we identified the most prominent peaks, determined their widths, and integrated over those widths to determine what percentage of tremor-band power was contained within the peaks. We identified for each instance the number of peaks, the width of each peak, the percentage of power contained in each peak, and the total percentage of tremor band power contained in all the peaks. Results and Discussion. The initial findings show that patients with severe tremor tend to have distinct peaks within the tremor band. Patients with less severe tremor have a greater number of instances where significant peaks are present in the tremor band. Many factors could cause this, one being that the power spectra of patients with less severe tremor tends to be of a broad-band nature. This suggests that tremor stems from a high concentration of muscular power at a frequency within the range of 4-8 Hz. Significance. This research aims to determine the spectral distribution of tremor in patients with Essential Tremor. From this characterization, we can analyze the power and phase differences between muscles. To determine the mechanical source of tremor, we can then find to what extent tremorogenic activity is represented by significant out of phase tremor-band activity in antagonist muscles verses significant tremor-band activity in only one muscle. Understanding the source of tremor will allow us to better identify which muscles are most responsible for it and therefore where is best to intervene with tremor suppression techniques. Acknowledgements: This research was supported by NIH grant R15 NS087447-02.
References
[1] Bhatia, K. P., et al. 2018. Mov. Disord., 33(1).
[2] Anouti, A., et al. 1995. West. J. Med., 162(6)
[3] Pigg, A. C., et al. 2020. Clin. Neurophysiol., 131.
A Qualitative and Quantitative Description of Maize Stem Failure Initiation and Progression
Cole Dunn, Brigham Young University
Faculty Mentor: Douglas Cook, Brigham Young University
SESSION B (10:45AM-12:15PM)
POSTER B26
Maize stalk failure often typically involves Brazier buckling, but the initiation of failure is poorly understood. In hollow tubes, buckling is controlled entirely by cross-sectional ovalization, but the septated, pith-filled stems of maize stalk are more complex. To study the initiation and progression of the stem failure, we created a measurement system consisting of a camera integrated with a universal testing machine to simulate and document a 3-point bending test on individual stalks. The camera moves in parallel with the loading anvil, thus preserving a consistent viewing perspective. The universal testing machine triggers the camera and records the time stamp of individual photographs. This system collects force, deformation, and image data during the test. Custom software was used to track landmarks on the stem, thus allowing a consistent cross-section to be analyzed during testing, even if substantial rotation of the stalk occurs during bending. Results revealed two failure mechanisms. First, localized buckling of the stem increased mechanical stresses, which caused tissue failure and collapse. Second, tissue failure sometimes occurred spontaneously, which tended to initiate buckling behavior. Thus, whichever mode is weakest in a particular stalk will happen first, and the remaining mode will appear as part of the structural collapse process. This information provides a more complete understanding of maize stalk failure.
A novel sensor that provides simultaneous measurement of force, deformation, and location of force
Jordan Porter, Brigham Young University
Faculty Mentor: Douglas Cook, Brigham Young University
SESSION B (10:45AM-12:15PM)
POSTER B27
At this conference we will present a novel sensor consisting of a cantilever beam with mounted strain gauges. Our patent-pending sensor can simultaneously measure the magnitude of an applied force, the location of the force, and the deformation of the beam caused by the force. The sensor uses a minimum of two strain gauges attached at different longitudinal locations along the beam. Additional strain gauges provide more sensitivity but do not affect the core functionality of the sensor. As a force is pressed on the beam, each strain gauge outputs a voltage proportional to strain, which we read into a data acquisition system. The beam requires initial calibration by hanging known weights at precise locations and recording the voltages from the strain gauges. The beam’s dimensions and material properties, as well as the location of the strain gauges are required to make these calculations. Once the beam has been calibrated, it can measure a force, location, and displacement at any location along the beam. We will demonstrate the performance of the sensor and discuss challenges and future work.
Identification of Anomalous PurpleAir Particulate Matter Sensors
Nathan Searle, University of Utah
Faculty Mentor: Kerry Kelly, University of Utah
SESSION B (10:45AM-12:15PM)
POSTER B28
Particulate matter (PM) is a common air quality metric, as it can lead to a number of adverse health effects including asthma, heart attacks, and premature death. PM measurements are classified by particle size, and different size classes indicate different contaminants, such as dust and smoke. The PurpleAir low-cost PM sensors use a fan to draw air past a laser, and particles that pass the laser scatter light. The sensor then measures scattered light, which correlates to PM counts and mass concentrations. A fraction of the PurpleAir sensors installed since June 2021 appear to report different PM concentrations compared to sensors installed prior to June 2021. We identified potentially anomalous sensors by comparing the measurements of these new sensors with the measurements of sensors installed prior to June 2021. Each sensor installed after June 2021 was paired with an older sensor installed in the same geographic location to understand whether localized PM readings were consistent. Historical PM concentration readings from the summer of 2022 were collected from each pair of sensors and used to determine the likelihood of the new sensor reporting anomalous values. This process also identified a threshold for which a newly installed sensor could be flagged if PM counts differed significantly from the previously installed sensor in the region. Our preliminary results suggest hundreds of PurpleAir sensors that measured significantly higher PM counts for the smallest particle sizes (less than or equal to 0.3 microns in diameter), while simultaneously reading significantly lower counts for large particle sizes (greater than 1.0 microns in diameter). These differences also suggest that these new sensors may require different PM correction factors than those not exhibiting this anomalous behavior. More research is needed to determine appropriate correction factors and the long-term prevalence of these newer PurpleAir PM sensors.