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In translating the Russian-language math paper “On Applications of Graph Theory for the Description and Analysis of Information Flow Diagrams in Control Systems” (V.L. Epstein, 1964) we endeavor not only to analyze the specific applications of this paper’s analysis of adjacency matrices to current topics of interest in graph theory,

In translating the Russian-language math paper “On Applications of Graph Theory for the Description and Analysis of Information Flow Diagrams in Control Systems” (V.L. Epstein, 1964) we endeavor not only to analyze the specific applications of this paper’s analysis of adjacency matrices to current topics of interest in graph theory, but also to demonstrate in general the value of translating foreign language papers.

ContributorsSaarinen, Emma Catherine (Author) / Inozemtseva, Julia (Thesis director) / Suslov, Sergei (Committee member) / School of Mathematical and Statistical Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12
Description
Natural Language Processing (NLP) techniques have increasingly been used in finance, accounting, and economics research to analyze text-based information more efficiently and effectively than primarily human-centered methods. The literature is rich with computational textual analysis techniques applied to consistent annual or quarterly financial fillings, with promising results to identify similarities

Natural Language Processing (NLP) techniques have increasingly been used in finance, accounting, and economics research to analyze text-based information more efficiently and effectively than primarily human-centered methods. The literature is rich with computational textual analysis techniques applied to consistent annual or quarterly financial fillings, with promising results to identify similarities between documents and firms, in addition to further using this information in relation to other economic phenomena. Building upon the knowledge gained from previous research and extending the application of NLP methods to other categories of financial documents, this project explores financial credit contracts, better understanding the information provided through their textual data by assessing patterns and relationships between documents and firms. The main methods used throughout this project is Term Frequency-Inverse Document Frequency (to represent each document as a numerical vector), Cosine Similarity (to measure the similarity between contracts), and K-Means Clustering (to organically derive clusters of documents based on the text included in the contract itself). Using these methods, the dimensions analyzed are various grouping methodologies (external industry classifications and text derived classifications), various granularities (document-wise and firm-wise), various financial documents associated with a single firm (the relationship between credit contracts and 10-K product descriptions), and how various mean cosine similarity distributions change over time.
ContributorsLiu, Jeremy J (Author) / Wahal, Sunil (Thesis director) / Bharath, Sreedhar (Committee member) / School of Mathematical and Statistical Sciences (Contributor) / School for the Future of Innovation in Society (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description
Markov Chain Monte-Carlo methods are a Bayesian approach to predictive statistics, which takes advantage of prior beliefs and conditions as well as the existing data to produce posterior distributions of relevant parameters. This approach, implementable through the JAGS packaging in R, is promising for its impact on the diagnostics space,

Markov Chain Monte-Carlo methods are a Bayesian approach to predictive statistics, which takes advantage of prior beliefs and conditions as well as the existing data to produce posterior distributions of relevant parameters. This approach, implementable through the JAGS packaging in R, is promising for its impact on the diagnostics space, which is a critical bottleneck for pandemic planning and rapid response. Specifically, these methods provide the means to optimize diagnostic testing, for example, by determining whether it is best to test individuals in a certain locale once or multiple times. This study compares the expected accuracy of single and double testing under two specific conditions, a general and Icelandic test case, in order to ascertain the validity of MCMC methods in this space and inform decisionmakers and future research in the space. Models based on this platform may eventually be tailored to the priors of specific locales. Additionally, the ability to test multiple regimes of real or simulated data while maintaining uncertainty widens the pool of researchers that can impact the space. In future studies, ensemble methods investigating the full range of parameters and their combinations can be studied.
ContributorsSuresh, Tarun (Author) / Naufel, Mark (Thesis director) / Panchanathan, Sethuraman (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
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Description
Post-truth has become a household word since the start of 2016. Post-truth is the concept that facts are becoming less useful towards swaying popular opinion. Post-truth is based off the ideation that the truth is laced in the metaphysical, which means that facts are independent of the human mind. Post-truth

Post-truth has become a household word since the start of 2016. Post-truth is the concept that facts are becoming less useful towards swaying popular opinion. Post-truth is based off the ideation that the truth is laced in the metaphysical, which means that facts are independent of the human mind. Post-truth states two methods in which we derive truth: one is an objective truth, or a statement based on scientific and statistical analysis; the other is or a subjective truth, or a statement based on a feeling or value. Objective truth and subjective truth are interpretations of the “truth”: where objective truths use objective methods, such as research and statistics, and subjective truths use subjective methods, such as emotions or values. Further interpretations of post-truth interpret post-truth being a struggle between the objective truth and the subjective truth, and that objective truths are the correct interpretation of the truth. However, the current interpretation of post-truth becomes problematic. The case studies presented show that something that could be considered a subjective truth is grounded in reality, even though it is objectively wrong. There are instances where statistical analysis fails in its goals to represent reality in both war and science. There are also instances where capitalizing on the strongest emotional aspect of an issue creates a better understanding of that issue. The objective and subjective truths may not conflict with each other, in fact they may inform each other. The thesis concludes that a different interpretation of truth should be used to understand post-truth.
ContributorsSora, Nicholas (Author) / Fette, Donald (Thesis director) / O'Neill, Joseph (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Interictal spikes have been used to diagnose idiopathic seizure disorder and localize the seizure onset zone. Interictal spikes are thought to arise primarily from large excitatory postsynaptic potentials, and the role of interictal spikes in idiopathic seizure disorder and epileptogenesis remains unclear. We evaluated how local voltage changes due

Interictal spikes have been used to diagnose idiopathic seizure disorder and localize the seizure onset zone. Interictal spikes are thought to arise primarily from large excitatory postsynaptic potentials, and the role of interictal spikes in idiopathic seizure disorder and epileptogenesis remains unclear. We evaluated how local voltage changes due to interictal spikes impact action potential generation and firing using intracellular recordings from human tissue and the Hodgkin-Huxley model. During interictal spikes, bursts of action potentials underwent variable degrees of depolarization-induced inactivation in the intracellular data. Intracellular recordings in neocortical slices of human brain tissue confirmed that bursts of inactivated action potentials occurred during spontaneous paroxysmal depolarization shifts. These ex vitro findings were predicted using the Hodgkin-Huxley model and showed inactivated action potentials being generated by large depolarizations. As the amplitude of the interictal spike increased, there was a progression from low firing rate normal action potentials to higher firing rate normal action potentials to inactivated action potentials. The results show that the Hodgkin-Huxley model confirmed the effect of large interictal spike depolarizations on action potential firing and inactivation. This supports a key element in the hypothesis that interictal spikes, and the associated action potential firing, may alter the electrical environment of the brain and contribute to idiopathic seizure disorder.
ContributorsLossner, Lauren Nicole (Author) / Greger, Bradley (Thesis director) / Foldes, Stephen (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12
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Description
Eosinophilic Esophagitis (EoE) is a chronic autoimmune disease that causes inflammation of the esophagus due to food allergy. In pediatric EoE, remission can be reduced by 95% through the use of hypoallergenic amino acid formulas (AAF), however its bitter taste gives it poor palatability, making nutrition difficult. This thesis highlights

Eosinophilic Esophagitis (EoE) is a chronic autoimmune disease that causes inflammation of the esophagus due to food allergy. In pediatric EoE, remission can be reduced by 95% through the use of hypoallergenic amino acid formulas (AAF), however its bitter taste gives it poor palatability, making nutrition difficult. This thesis highlights the problem of poor palatability of AAF's and explores the idea of prototyping a new flavor enhanced recipe to minimize bitterness for EoE patients and how to evaluate it through sensory evaluation practices. Along the way, I also discovered that quail egg homogenate has novel therapeutic potential to reduce EoE symptoms.
ContributorsBorah, Priya Anjali (Co-author) / Holmes, Katherine (Co-author) / Serrano, Osvin (Co-author) / Spackman, Christy (Thesis director) / Schroeder, Shauna (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12
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Description
The phenomenon known as startReact is the fast, involuntary execution of a planned movement triggered by a startling acoustic stimulus. StartReact has previously been analyzed in simple motor movements such as finger abduction tasks, hand grasp tasks, and elbow extension tasks. More complex movements have also been analyzed, but there

The phenomenon known as startReact is the fast, involuntary execution of a planned movement triggered by a startling acoustic stimulus. StartReact has previously been analyzed in simple motor movements such as finger abduction tasks, hand grasp tasks, and elbow extension tasks. More complex movements have also been analyzed, but there have been limited studies that look into functional complex tasks that require end-point accuracy. The objective of this project was to assess the ability to elicit startReact in tasks that simulate activities of daily living like feeding or picking up a glass of water. We hypothesized that a startReact response would be present in complex functional tasks, but the response would not be as accurate due to the increase in speed. Five subjects performed a simulated feeding task by moving kidney beans from one target to another where the end target changed in diameter as well as, a simulated drinking task where the subject moved a cup full of beads from one target to another. The hypothesis was supported due to a significant difference between no stimulus and stimulus trials for tricep muscle onset time, duration time, and the accuracy parameters of amount of beans dropped and weight in beads dropped. The results coincided with previous studies where subjects compensated for the change in diameter by increasing reaction time as the target diameter size decreased. The data obtained contradicted a previous study in relation to the duration time between the tasks due to our smallest diameter size having a faster duration time in comparison to the other diameter sizes. This study provides preliminary data that could assist researchers and clinicians in improving physical therapy methods for patients with impaired upper extremity motor movements.
ContributorsRiggs, Cassie Rebekah (Author) / Honeycutt, Claire (Thesis director) / Schaefer, Sydney (Committee member) / Harrington Bioengineering Program (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12
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Description
Water scarcity is still an issue across the globe, so nonconventional desalination methods need to be developed to be able to get access to clean, safe water. One such method being studied is the pervaporation system, a membrane process that uses a vapor pressure differential to drive the system. There

Water scarcity is still an issue across the globe, so nonconventional desalination methods need to be developed to be able to get access to clean, safe water. One such method being studied is the pervaporation system, a membrane process that uses a vapor pressure differential to drive the system. There is a need to find the efficiency of the cold trap condenser that is used to collect the permeate so that a thermodynamic model can be fully developed to assist in the development of an industrial scale pervaporation system. An efficiency was not able to be confidently found, but it is believe to be between 95-100%.
Created2020-12
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Description
Tactile and proprioceptive sensory feedback are the two sensory modalities that make up haptic sensation. The degree which these two sensory modalities are integrated together is not very well known. To investigate this issue a set of experiments were set into motion separating these sensory modalities and testing what happens

Tactile and proprioceptive sensory feedback are the two sensory modalities that make up haptic sensation. The degree which these two sensory modalities are integrated together is not very well known. To investigate this issue a set of experiments were set into motion separating these sensory modalities and testing what happens when a person’s proprioceptive system is perturbed. A virtual reality system with haptic feedback along with a weighted object were utilized in a reach, grasp, and lift task. The subjects would lift two objects sequentially and try to judge which one was heavier. This project was split into three different experiments to measure the subject’s perception in different situations. The first experiment utilized the virtual reality system to measure the perception when the subject only has proprioceptive inputs. The second experiment would include the virtual reality system and the weighted object to act as a comparison to the first experiment with the additional tactile input. The third experiment would then add perturbations to the proprioceptive inputs through the virtual reality system to investigate how perception will change. Results from experiment 1 and 2 showed that subjects are almost just as accurate with weight discrimination even if they only have proprioceptive inputs however, subjects are much more consistent in their weight discrimination with both sensory modalities. Results from experiment 3 showed that subjective perception does change when the proprioception is perturbed but the magnitude of that change in perception depends on the perturbation performed.
ContributorsPerrine, Jacob (Author) / Santello, Marco (Thesis director) / Toma, Simone (Committee member) / Harrington Bioengineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12
Description
This paper is a survey of the Oribatid mites of the North American deserts. It contains four chapters. Chapter 1 gives an overview of the biology of mites and oribatids. I talk about their phylogeny, body parts, food sources, habitats, and lifecycle. In Chapter 2, I identify a group of

This paper is a survey of the Oribatid mites of the North American deserts. It contains four chapters. Chapter 1 gives an overview of the biology of mites and oribatids. I talk about their phylogeny, body parts, food sources, habitats, and lifecycle. In Chapter 2, I identify a group of 59 oribatid species with cosmopolitan or semi-cosmopolitan distributions and examine how the number of biogeographical regions where a species has been detected relates to body length and to reproductive mode (sexual or parthenogenetic). I also present an illustrated guide (File S1) to 58 of these species for use in identifying cosmopolitan species in oribatid surveys. Chapter 3 describes the current state of knowledge of oribatid diversity in the southwestern US and northern Mexico. In total, I was able to find records for 340 oribatid species from this region in the published literature and museum collections. However, we can see that some states, such as Arizona and Sonora, do not have many published records and that further studies are needed to more fully characterize oribatid diversity within this region. Finally, Chapter 4 describes some preliminary efforts to culture oribatid mites sampled from oak woodland in the Santa Rita Mountains of southeast Arizona. Although this work was interrupted by the COVID-19 crisis, I was able to keep three oribatid species in captivity long enough for them to lay eggs and for some of these eggs to hatch.
ContributorsZhao, Erxuan (Author) / Taylor, Jay (Thesis director) / Pratt, Stephen (Committee member) / School of Mathematical and Statistical Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-12