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- Creators: Harrington Bioengineering Program
Description
Glioblastoma multiforme (GBM) is a malignant, aggressive and infiltrative cancer of the central nervous system with a median survival of 14.6 months with standard care. Diagnosis of GBM is made using medical imaging such as magnetic resonance imaging (MRI) or computed tomography (CT). Treatment is informed by medical images and includes chemotherapy, radiation therapy, and surgical removal if the tumor is surgically accessible. Treatment seldom results in a significant increase in longevity, partly due to the lack of precise information regarding tumor size and location. This lack of information arises from the physical limitations of MR and CT imaging coupled with the diffusive nature of glioblastoma tumors. GBM tumor cells can migrate far beyond the visible boundaries of the tumor and will result in a recurring tumor if not killed or removed. Since medical images are the only readily available information about the tumor, we aim to improve mathematical models of tumor growth to better estimate the missing information. Particularly, we investigate the effect of random variation in tumor cell behavior (anisotropy) using stochastic parameterizations of an established proliferation-diffusion model of tumor growth. To evaluate the performance of our mathematical model, we use MR images from an animal model consisting of Murine GL261 tumors implanted in immunocompetent mice, which provides consistency in tumor initiation and location, immune response, genetic variation, and treatment. Compared to non-stochastic simulations, stochastic simulations showed improved volume accuracy when proliferation variability was high, but diffusion variability was found to only marginally affect tumor volume estimates. Neither proliferation nor diffusion variability significantly affected the spatial distribution accuracy of the simulations. While certain cases of stochastic parameterizations improved volume accuracy, they failed to significantly improve simulation accuracy overall. Both the non-stochastic and stochastic simulations failed to achieve over 75% spatial distribution accuracy, suggesting that the underlying structure of the model fails to capture one or more biological processes that affect tumor growth. Two biological features that are candidates for further investigation are angiogenesis and anisotropy resulting from differences between white and gray matter. Time-dependent proliferation and diffusion terms could be introduced to model angiogenesis, and diffusion weighed imaging (DTI) could be used to differentiate between white and gray matter, which might allow for improved estimates brain anisotropy.
ContributorsAnderies, Barrett James (Author) / Kostelich, Eric (Thesis director) / Kuang, Yang (Committee member) / Stepien, Tracy (Committee member) / Harrington Bioengineering Program (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2016-05
Description
The global population over the age of 60 is estimated to rise to 23% by 2050 only increase the prevalence of functional neurological disorders and stroke. Increase in cases of functional neurological disorders and strokes will place a greater burden on the healthcare industry, specifically physical therapy. Physical therapy is vital for a patient’s recovery of motor function which is time demanding and taxing on the physical therapist. Wearable robotics have been proven to improve functional outcomes in gait rehabilitation by providing controlled high dosage and high-intensity training. Accurate control strategies for assistive robotic exoskeletons are vital for repetitive high precisions assistance for cerebral plasticity to occur.
This thesis presents a preliminary determination and design of a control algorithm for an assistive ankle device developed by the ASU RISE Laboratory. The assistive ankle device functions by compressing a spring upon heel strike during gait, remaining compressed during mid-stance and then releasing upon initiation of heel-off. The relationship between surface electromyography and ground reactions forces were used for identification of user-initiated heel-off. The muscle activation of the tibialis anterior combined with the ground reaction forces of the heel pressure sensor generated potential features that will be utilized in the revised control algorithm for the assistive ankle device. Work on this project must proceed in order to test and validate the revised control algorithm to determine its accuracy and precision.
This thesis presents a preliminary determination and design of a control algorithm for an assistive ankle device developed by the ASU RISE Laboratory. The assistive ankle device functions by compressing a spring upon heel strike during gait, remaining compressed during mid-stance and then releasing upon initiation of heel-off. The relationship between surface electromyography and ground reactions forces were used for identification of user-initiated heel-off. The muscle activation of the tibialis anterior combined with the ground reaction forces of the heel pressure sensor generated potential features that will be utilized in the revised control algorithm for the assistive ankle device. Work on this project must proceed in order to test and validate the revised control algorithm to determine its accuracy and precision.
ContributorsGaytan-Jenkins, Daniel Rinaldo (Author) / Zhang, Wenlong (Thesis director) / Tyler, Jamie (Committee member) / Harrington Bioengineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Smart contrast agents allow for noninvasive study of specific events or tissue conditions inside of a patient's body using Magnetic Resonance Imaging (MRI). This research aims to develop and characterize novel smart contrast agents for MRI that respond to temperature changes in tissue microenvironments. Transmission Electron Microscopy, Nuclear Magnetic Resonance, and cell culture growth assays were used to characterize the physical, magnetic, and cytotoxic properties of candidate nanoprobes. The nanoprobes displayed thermosensitve MR properties with decreasing relaxivity with temperature. Future work will be focused on generating and characterizing photo-active analogues of the nanoprobes that could be used for both treatment of tissues and assessment of therapy.
ContributorsHussain, Khateeb Hyder (Author) / Kodibagkar, Vikram (Thesis director) / Stabenfeldt, Sarah (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor) / School of Mathematical and Statistical Sciences (Contributor)
Created2014-05
Description
Glioblastoma Multiforme (GBM) is an aggressive and deadly form of brain cancer with a median survival time of about a year with treatment. Due to the aggressive nature of these tumors and the tendency of gliomas to follow white matter tracks in the brain, each tumor mass has a unique growth pattern. Consequently it is difficult for neurosurgeons to anticipate where the tumor will spread in the brain, making treatment planning difficult. Archival patient data including MRI scans depicting the progress of tumors have been helpful in developing a model to predict Glioblastoma proliferation, but limited scans per patient make the tumor growth rate difficult to determine. Furthermore, patient treatment between scan points can significantly compound the challenge of accurately predicting the tumor growth. A partnership with Barrow Neurological Institute has allowed murine studies to be conducted in order to closely observe tumor growth and potentially improve the current model to more closely resemble intermittent stages of GBM growth without treatment effects.
ContributorsSnyder, Lena Haley (Author) / Kostelich, Eric (Thesis director) / Frakes, David (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Harrington Bioengineering Program (Contributor)
Created2014-05
Description
This paper begins by exploring the prior research that has shown how eating a plant-based diet can affect the human body. Some of these effects include: improved mood, energy levels, gut health, alkalized urine pH, as well as, lowering the risk of hormonal imbalance, kidney stones, diabetes, cancer, and coronary artery disease. The worries that generally accompany eating a fully vegan diet, which include, malnutrition and protein deficiency, are also addressed in the background research. In attempt to build upon previous research, a weeklong experiment was conducted testing 3 different factors, which include: gut health, improved mood, and urine pH. Mood states were measured quantifiably using a POMS (profile of mood states) test. Gut health was measured using several factors, including consistency and frequency of bowel movements, as well as, GI discomfort. Two 24-hour urine samples were collected from each of the subjects to compare the pH of their urine before and after the study. The sample size of this study included 15 healthy, non-smoking, subjects, between 18-30 years of age. The subjects were split up into 3 stratified random samples, including, an omnivore control group, vegan control group, and experimental vegan group. The experimental vegans had eaten meat/eggs/dairy regularly for their whole lives before the start of the study, and had consented to eating a vegan diet for the entirety of one week. While the data from the control groups remained mostly constant as predicted, the results from the experimental group were shown to have a significantly better mood (P<0.05) after one week, as well as, a significantly higher urine pH (P < 0.025) than they did before the study. However, the experimental group did not show a significant change in stool frequency, consistency, or GI discomfort within one week. The vegan control group, which included subjects who had eaten a plant-based diet for 1-3 years, had much better gut health scores. This leads us to believe that the vegan gut microbiome takes much longer to transform into than just one week unlike urine pH and mood, which can take as little as one week. These findings warrant further investigation.
ContributorsMacias, Lindsey Kaori (Author) / Johnston, Carol (Thesis director) / Katsanos, Christos (Committee member) / Harrington Bioengineering Program (Contributor) / School of Nutrition and Health Promotion (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
In epilepsy, malformations that cause seizures often require surgery. The purpose of this research is to join forces with the Multi-Center Epilepsy Lesion Detection (MELD) project at University College London (UCL) in order to improve the process of detecting lesions in patients with drug-resistant epilepsy. This, in turn, will improve surgical outcomes via more structured surgical planning. It is a global effort, with more than 20 sites across 5 continents. The targeted populations for this study include patients whose epilepsy stems from Focal Cortical Dysplasia. Focal Cortical Dysplasia is an abnormality of cortical development, and causes most of the drug-resistant epilepsy. Currently, the creators of MELD have developed a set of protocols which wrap various
commands designed to streamline post-processing of MRI images. Using this partnership, the Applied Neuroscience and Technology Lab at PCH has been able to complete production of a post-processing pipeline which integrates locally sourced smoothing techniques to help identify lesions in patients with evidence of Focal Cortical Dysplasia. The end result is a system in which a patient with epilepsy may experience more successful post-surgical results due to the
combination of a lesion detection mechanism and the radiologist using their trained eye in the presurgical stages. As one of the main points of this work is the global aspect of it, Barrett thesis funding was dedicated for a trip to London in order to network with other MELD project collaborators. This was a successful trip for the project as a whole in addition to this particular thesis. The ability to troubleshoot problems with one another in a room full of subject matter
experts allowed for a high level of discussion and learning. Future work includes implementing machine learning approaches which consider all morphometry parameters simultaneously.
commands designed to streamline post-processing of MRI images. Using this partnership, the Applied Neuroscience and Technology Lab at PCH has been able to complete production of a post-processing pipeline which integrates locally sourced smoothing techniques to help identify lesions in patients with evidence of Focal Cortical Dysplasia. The end result is a system in which a patient with epilepsy may experience more successful post-surgical results due to the
combination of a lesion detection mechanism and the radiologist using their trained eye in the presurgical stages. As one of the main points of this work is the global aspect of it, Barrett thesis funding was dedicated for a trip to London in order to network with other MELD project collaborators. This was a successful trip for the project as a whole in addition to this particular thesis. The ability to troubleshoot problems with one another in a room full of subject matter
experts allowed for a high level of discussion and learning. Future work includes implementing machine learning approaches which consider all morphometry parameters simultaneously.
ContributorsHumphreys, Zachary William (Author) / Kodibagkar, Vikram (Thesis director) / Foldes, Stephen (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
A Personal Journey Through Physical Fitness chronicles one individual's academic and physical journey through fitness. An ex college gymnast after exiting formal sports looks to academics for the answers to accomplish the goal of working out one hour a day and feeling as well as being physically fit as a result. This research resulted in finding the five pillars of physical fitness; which are Endurance, Flexibility, Strength, Balance, and Agility. After determining that these were the five primary pillars of physical fitness a workout plan was made based on and focused on improving them. This work out plan included running and hiking for endurance, high intensity interval training for agility, endurance and strength, stretching at the end of every work out, and a weightlifting program that utilized push, pull, and lower body days. It also utilized yoga for flexibility, recovery, and balance. Additionally, gymnastic ring strength was included to help develop balance and strength. Then a four-week trial period was executed taking measurements at the beginning and end of the plan. The results of the five-pillar plan were quantified using physical metrics. There was improvement in all of the pillars: Endurance, Flexibility, Strength, Balance, and Agility. However it should be noted there was not a direct measure for balance making its improvement much more subjective and qualitative than quantitative. In addition to having physical metrics of health and increased fitness there were mental side effects such as of feeling good and more relaxed throughout the process. At the end of each week of the four-week workout trial mental and physical feelings were recorded and included in the study. The method and plan were successful and created in a way that others could follow this four-week plan to improve their own physical health.
ContributorsVlastos, Joseph Nicholas (Author) / Kaplan, Robert (Thesis director) / Roses-Thema, Cynthia (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
The International Dyslexia Association defines dyslexia as a learning disorder that is characterized by poor spelling, decoding, and word recognition abilities. There is still no known cause of dyslexia, although it is a very common disability that affects 1 in 10 people. Previous fMRI and MRI research in dyslexia has explored the neural correlations of hemispheric lateralization and phonemic awareness in dyslexia. The present study investigated the underlying neurobiology of five adults with dyslexia compared to age- and sex-matched control subjects using structural and functional magnetic resonance imaging. All subjects completed a large battery of behavioral tasks as part of a larger study and underwent functional and structural MRI acquisition. This data was collected and preprocessed at the University of Washington. Analyses focused on examining the neural correlates of hemispheric lateralization, letter reversal mistakes, reduced processing speed, and phonemic awareness. There were no significant findings of hemispheric differences between subjects with dyslexia and controls. The subject making the largest amount of letter reversal errors had deactivation in their cerebellum during the fMRI language task. Cerebellar white matter volume and surface area of the premotor cortex was the largest in the individual with the slowest reaction time to tapping. Phonemic decoding efficiency had a high correlation with neural activation in the primary motor cortex during the fMRI motor task (r=0.6). Findings from the present study suggest that brain regions utilized during motor control, such as the cerebellum, premotor cortex, and primary motor cortex, may have a larger role in dyslexia then previously considered. Future studies are needed to further distinguish the role of the cerebellum and other motor regions in relation to motor control and language processing deficits related to dyslexia.
ContributorsHoulihan, Chloe Carissa Prince (Author) / Rogalsky, Corianne (Thesis director) / Peter, Beate (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Concussions and traumatic brain injuries are mechanical events which can derive from no specific activity or event. However, these injuries occur often during athletic and sporting events but many athletes experiencing these symptoms go undiagnosed and continue playing without proper medical attention. The current gold standard for diagnosing athletes with concussions is to have medical professionals on the sidelines of events to perform qualitative standardized assessments which may not be performed frequently enough and are not specialized for each athlete. The purpose of this report is to discuss a study sanctioned by Arizona State University's Project HoneyBee and additional affiliations to validate a third-party mouth guard device product to recognize and detect force impacts blown to an athlete's head during athletic activity. Current technology in health monitoring medical devices can allow users to apply this device as an additional safety mechanism for early concussion awareness and diagnosis. This report includes the materials and methods used for experimentation, the discussion of its results, and the complications which occurred and areas for improvement during the preliminary efforts of this project. Participants in the study were five non-varsity ASU Wrestling athletes who volunteered to wear a third-party mouth guard device during sparring contact at practice. Following a needed calibration period for the devices, results were recorded both through visual observation and with the mouth guard devices using an accelerometer and gyroscope. This study provided a sound understanding for the operation and functionality of the mouth guard devices. The mouth guard devices have the capability to provide fundamental avenues of research for future investigations.
ContributorsTielke, Austin Wyatt (Author) / Ross, Heather (Thesis director) / LaBelle, Jeffrey (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
The dilemma of the lack of prenatal and neonatal healthcare has been prevalent among third world countries for many years. The lack of prenatal healthcare has been shown to have direct links to spontaneous preterm births from which low-birth weight in babies can be a result. The World Health Organization has identified preterm birth as one of the biggest overseen burdens in developing countries.
This study seeks to answer the research questions: What are the major risk factors associated with the lack of prenatal and neonatal healthcare in developing countries? What are potential routes of intervention (ROI) to help these countries? The goal is to analyze the risk factors and determine if there are any ROIs available to minimize potential incidents or accidents associated with complications of preterm birth.
A few potential risk factors include: poverty, a mother’s lack of education, a lack of professional visitation during pregnancy, having a short cervix, and routine use of Ultrasound. This research paper has identified that keeping ultrasound diagnostics to a minimum, seeking professional help during pregnancy, incorporating corticosteroids for preterm births, implementing Kangaroo Mother Care, and Cervical Cerclage are interventions that can reduce preterm births and the associated complications that come with it. We believe that further research, regarding compliance of each of these interventions, would show reduction of preterm births and low birth weight in developing countries.
This study seeks to answer the research questions: What are the major risk factors associated with the lack of prenatal and neonatal healthcare in developing countries? What are potential routes of intervention (ROI) to help these countries? The goal is to analyze the risk factors and determine if there are any ROIs available to minimize potential incidents or accidents associated with complications of preterm birth.
A few potential risk factors include: poverty, a mother’s lack of education, a lack of professional visitation during pregnancy, having a short cervix, and routine use of Ultrasound. This research paper has identified that keeping ultrasound diagnostics to a minimum, seeking professional help during pregnancy, incorporating corticosteroids for preterm births, implementing Kangaroo Mother Care, and Cervical Cerclage are interventions that can reduce preterm births and the associated complications that come with it. We believe that further research, regarding compliance of each of these interventions, would show reduction of preterm births and low birth weight in developing countries.
ContributorsHuapaya, Eduardo Luciano (Author) / Muthuswamy, Jitendran (Thesis director) / Comar, William (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05