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Description
Electrical nerve stimulation is a promising drug-free technology that could treat a variety of ailments and disorders. Methods like Vagus Nerve Stimulation have been used for decades to treat disorders like epilepsy, and research with non-invasive vagus nerve stimulation has shown similar effects as its invasive counterpart. Non-invasive nerve stimulation methods like vagus nerve stimulation could help millions of people treat and manage various disorders.
This study observed the effects of three different non-invasive nerve stimulation paradigms in human participants. The first study analyzed the safety and efficacy of transcutaneous auricular vagal nerve stimulation in healthy humans using a bilateral stimulation protocol with uniquely designed dry-hydrogel electrodes. Results demonstrate bilateral auricular vagal nerve stimulation has significant effects on specific parameters of autonomic activity and is safe and well tolerated. The second study analyzed the effects of non-invasive electrical stimulation of a region on the side of the neck that contains the Great Auricular Nerve and the Auricular Branch of the Vagus Nerve called the tympanomastoid fissure on golf hitting performance in healthy golfers. Results did not show significant effects on hitting performance or physiological activity, but the nerve stimulation had significant effects on reducing state-anxiety and improving the quality of feel of each shot. The third study analyzed the effects of non-invasive nerve stimulation of cervical nerves on the back of the neck on putting performance of yips-affected golfers. Results demonstrated that cervical nerve stimulation had significant effects on improving putting performance but did not have significant effects on physiological activity. Data from these studies show there are potential applications for non-invasive electrical nerve stimulation for healthy and athletic populations. Future research should also examine the effects of these stimulation methods in clinical populations.
This study observed the effects of three different non-invasive nerve stimulation paradigms in human participants. The first study analyzed the safety and efficacy of transcutaneous auricular vagal nerve stimulation in healthy humans using a bilateral stimulation protocol with uniquely designed dry-hydrogel electrodes. Results demonstrate bilateral auricular vagal nerve stimulation has significant effects on specific parameters of autonomic activity and is safe and well tolerated. The second study analyzed the effects of non-invasive electrical stimulation of a region on the side of the neck that contains the Great Auricular Nerve and the Auricular Branch of the Vagus Nerve called the tympanomastoid fissure on golf hitting performance in healthy golfers. Results did not show significant effects on hitting performance or physiological activity, but the nerve stimulation had significant effects on reducing state-anxiety and improving the quality of feel of each shot. The third study analyzed the effects of non-invasive nerve stimulation of cervical nerves on the back of the neck on putting performance of yips-affected golfers. Results demonstrated that cervical nerve stimulation had significant effects on improving putting performance but did not have significant effects on physiological activity. Data from these studies show there are potential applications for non-invasive electrical nerve stimulation for healthy and athletic populations. Future research should also examine the effects of these stimulation methods in clinical populations.
ContributorsHool, Nicholas (Author) / Tyler, William J (Thesis advisor) / Crews, Debbie (Committee member) / Muthuswamy, Jitendran (Committee member) / Helms Tillery, Stephen (Committee member) / Sebold, Brent (Committee member) / Arizona State University (Publisher)
Created2020
Description
Attending college is like embarking on a journey of self-discovery and transformation. Education as a heroic journey transforms students in such a way that it will invite them to re-examine their conceptual structures, as well as internalized cultural norms. While heroes make their way through their journey, they are often viewed as drawing upon different archetypes. By recognizing the strengths and weaknesses of each archetype, the Hero can consciously rely on the most beneficial attribute of this transformative journey. Despite the essential role of universal archetypes in students’ educational journey, they have been overlooked and replaced by a more functional approach in which personal development is neglected. Therefore, calling for a transformative educational approach in higher education has been advocated to push against the boundaries imposed by the functional approach and to help students transcend their personal boundaries. The purpose of this study is to discover the dominant Shadow archetypes of first-year college students and to explore the influence of archetypal unconscious traits on students’ self-efficacy. To investigate students’ archetypal personalities, two questionnaires: Pearson-Marr Archetypal Indicator (PMAI) and Sherer’s General Self-Efficacy Scale (SGSES), were applied. To investigate students’ perceptions on the influence of their Shadow archetypes, semi-structured online based interviews through Zoom were conducted. For the quantitative data analysis, statistical analysis was carried out using SPSS; and for the qualitative data analysis, deductive thematic analysis was used to analyze the interview protocols. It was revealed from the findings that the most active archetypes among first year college students are the Seeker, Jester, and Caregiver archetypes. The most common Shadow archetypes that are active among first year college students are the Idealist, Ruler, and the Warrior archetypes. The statistical analysis indicated that there is a linear relationship between the Shadow archetypes and students’ self-efficacy. The thematic analysis of semi-structured interviews revealed that first year college students’ academic self-efficacy is influenced by the traits of their Shadow archetypes in various ways. Some of these influences are lack of motivation, procrastination, inability to set goals, irresponsibility, and negative self-evaluation. Keywords: Shadow, Self-Knowledge, Archetypes, Self-efficacy, Transformative Education.
ContributorsAlqadi, Mona (Author) / Van Gelderen, Elly (Thesis advisor) / James, Mark (Committee member) / Roen, Duane (Committee member) / Arizona State University (Publisher)
Created2022
Description
Despite countless research reports, research studies, and studies of human psychology verifying that the Reid Method interrogation tactics used by police in the United States cause false confessions, the method is still heavily accepted and used on suspects everyday. This research paper will look into the Reid Method interrogation tactics, their connection to false confessions in order to establish a basis for repealing and replacing the Reid Method with an alternative interrogation technique. This paper will show that the guilt-presumptive nature of the Reid Method leads to innocent individuals falsely confessing and spending years in prison. Evidence of this phenomenon will be shown through research papers, studies, case examples, and an interview with a false confession expert Dr. Richard A. Leo. The Reid Method is problematic and jeopardizes the presumption of innocence for every citizen in the United States and should be repealed by an alternative interrogation technique called P.E.A.C.E in order for justice to be renewed.
ContributorsWorrell, Hayley (Author) / Niebuhr, Robert (Thesis director) / Adelman, Madeline (Committee member) / Barrett, The Honors College (Contributor) / School of Social Transformation (Contributor)
Created2022-05
Description
Although social cognitive deficits are considered a hallmark trait of schizophrenia, research on schizotypy and social cognition is inconsistent. The present study examines the associations among schizotypy, aberrant salience, and social cognition. Schizotypy and aberrant salience were assessed continuously using the Schizotypal Personality Questionnaire Brief Revised (SPQ-BR) and the Aberrant Salience Inventory (ASI). Social cognition was examined using The Awareness of Social Inference Test (TASIT), an audio-visual paradigm that taps into multiple domains of social cognition. Data from 849 undergraduate students was analyzed. Results indicated that schizotypy overall was not associated with social cognitive deficits. However, when schizotypy was analyzed dimensionally, positive schizotypy was associated with social cognitive impairments. Further, aberrant salience was revealed to be consistently associated with social cognitive impairments, except when positive schizotypy was included in the model. This suggests the possibility that positive schizotypy could mediate the association between aberrant salience and social cognition. Overall, this study highlights the importance of focusing on positive schizotypy and aberrant salience in future investigations of social cognitive difficulties in psychosis.
ContributorsArnett, Ciera (Author) / Karoly, Paul (Thesis advisor) / Corbin, William (Thesis advisor) / Brewer, Gene (Committee member) / Arizona State University (Publisher)
Created2021
Description
Over the past few years, research into the use of doped diamond in electronics has seen an exponential growth. In the course of finding ways to reduce the contact resistivity, nanocarbon materials have been an interesting focus. In this work, the transfer length method (TLM) was used to investigate Ohmic contact properties using the tri-layer stack Ti/Pt/Au on nitrogen-doped n-type conducting nano-carbon (nanoC) layers grown on (100) diamond substrates. The nanocarbon material was characterized using Secondary Ion Mass Spectrometry (SIMS), Scanning electron Microscopy (SEM) X-ray diffraction (XRD), Raman scattering and Hall effect measurements to probe the materials characteristics. Room temperature electrical measurements were taken, and samples were annealed to observe changes in electrical conductivity. Low specific contact resistivity values of 8 x 10^-5 Ωcm^2 were achieved, which was almost two orders of magnitude lower than previously reported values. The results were attributed to the increased nitrogen incorporation, and the presence of electrically active defects which leads to an increase in conduction in the nanocarbon. Further a study of light phosphorus doped layers using similar methods with Ti/Pt/Au contacts again yielded a low contact resistivity of about 9.88 x 10^-2 Ωcm^2 which is an interesting prospect among lightly doped diamond films for applications in devices such as transistors. In addition, for the first time, hafnium was substituted for Ti in the contact stack (Hf/Pt/Au) and studied on nitrogen doped nanocarbon films, which resulted in low contact resistivity values on the order of 10^-2 Ωcm^2. The implications of the results were discussed, and recommendations for improving the experimental process was outlined. Lastly, a method for the selective area growth of nanocarbon was developed and studied and the results provided an insight into how different characterizations can be used to confirm the presence of the nanocrystalline diamond material, the limitations due to the film thickness was explored and ideas for future work was proposed.
ContributorsAmonoo, Evangeline Abena (Author) / Thornton, Trevor (Thesis advisor) / Alford, Terry L (Thesis advisor) / Anwar, Shahriar (Committee member) / Theodore, David (Committee member) / Arizona State University (Publisher)
Created2023
Description
Human Immunodeficiency Virus (HIV) remains a persistent problem around the world, even though antiretroviral therapy has shown to be effective in reducing viral load and limiting transmission of the virus. Due to HIV’s infectious nature, visibility, the populations at risk, and its connections to race, class, and sexuality, it is more stigmatized than any other illness. HIV stigma has been associated with increased depression, social isolation, and poor psychological adjustment. HIV stigma can influence disclosure and care-seeking behavior. Internet-based interventions have shown to be effective in increasing knowledge on STIs and HIV, however, researchers have tested strategies that include educating participants on HIV to reduce stigma and have found that informational approaches alone are not effective. There is evidence that emotional intelligence and empathy are associated with prosocial behavior and influence attitudes towards stigmatized groups. Thus, this thesis aims to test an online intervention using an informational video from the Center for Disease Control and Prevention (CDC) in combination with an empathy-generating component to reduce stigma. It was hypothesized that the online intervention would increase HIV knowledge scores (H1), but stigma will only be reduced in the group introduced to the empathy-inducing component (H2) and those with high emotional intelligence would show the greatest reduction in stigmatizing attitudes (H3). Results did not support these hypotheses, suggesting that the CDC’s video does not significantly increase HIV knowledge in the general public. Further, the video intended to generate empathy and reduce stigma was also ineffective. These findings stress the need for further research and questions the effectiveness of empathy-generating interventions (e.g., FACES OF HIV, HIV Justice Network) to increase knowledge and reduce stigma. Future researchers should test the effectiveness of personalized interventions to reduce HIV-related stigma.
ContributorsEl-krab, Renee (Author) / Vargas, Perla (Thesis advisor) / Roberts, Nicole (Committee member) / Chen, Angela (Committee member) / Arizona State University (Publisher)
Created2020
Description
Scaling of the Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET) towards shorter channel lengths, has lead to an increasing importance of quantum effects on the device performance. Until now, a semi-classical model based on Monte Carlo method for instance, has been sufficient to address these issues in silicon, and arrive at a reasonably good fit to experimental mobility data. But as the semiconductor world moves towards 10nm technology, many of the basic assumptions in this method, namely the very fundamental Fermi’s golden rule come into question. The derivation of the Fermi’s golden rule assumes that the scattering is infrequent (therefore the long time limit) and the collision duration time is zero. This thesis overcomes some of the limitations of the above approach by successfully developing a quantum mechanical simulator that can model the low-field inversion layer mobility in silicon MOS capacitors and other inversion layers as well. It solves for the scattering induced collisional broadening of the states by accounting for the various scattering mechanisms present in silicon through the non-equilibrium based near-equilibrium Green’s Functions approach, which shall be referred to as near-equilibrium Green’s Function (nEGF) in this work. It adopts a two-loop approach, where the outer loop solves for the self-consistency between the potential and the subband sheet charge density by solving the Poisson and the Schrödinger equations self-consistently. The inner loop solves for the nEGF (renormalization of the spectrum and the broadening of the states), self-consistently using the self-consistent Born approximation, which is then used to compute the mobility using the Green-Kubo Formalism.
ContributorsJayaram Thulasingam, Gokula Kannan (Author) / Vasileska, Dragica (Thesis advisor) / Ferry, David (Committee member) / Goodnick, Stephen (Committee member) / Allee, David (Committee member) / Arizona State University (Publisher)
Created2017
Description
The body tilt illusion relates to one’s exaggerated perception of body tilt angle in comparison to reality. People tend to overestimate this illusion and feel that they are tilted at 45º when they are tilted less than 45º in reality. This illusion increases with lack of sensory cues and decreases when sensory cues are added. In the present study, distortion in the perception of body tilt was examined as a function of center of mass. There are gender differences in regards to where one’s center of mass lies on their body, with females having a lower center of mass on average compared to males (Elert, 2005). We used a human-sized 3D gyroscope to test participants’ experience of the body tilt illusion. The findings support that perception of body tilt is multisensory and that visual information as well as the tilting plane affects the magnitude of the illusion. This is consistent with the illusion being functional for helping people keep their balance. Yet, we did not find significant differences in the size of the illusion due to differences in center of mass. The pattern of findings supports that the body tilt illusion is relatively universal, and likely functional, but does not vary much due to individual body shape differences like center of mass.
ContributorsOverby, Ashlyn (Author) / Mcbeath, Micheal (Thesis director) / Baia, Sophia (Committee member) / Corbin, William (Committee member) / Cavanaugh-Toft, Carolyn (Committee member) / Barrett, The Honors College (Contributor) / Department of Psychology (Contributor)
Created2024-05
Description
Greater cross-disciplinary collaboration between the fields of sustainability and clinical psychology could lead to improved outcomes for both. Moreover, some forms of mental disorder, such as PTSD and Moral Injury, constitute serious challenges that require the attention of sustainability’s interdisciplinary, systems-focused, solutionsoriented approach. My research frames the impacts of combat-related psychological trauma on military veterans as a sustainability problem according to criteria put forward by Arnim Wiek’s Transformational Problem Solving framework. I also provide a review of studies demonstrating the treatment benefits of agricultural therapy for veterans diagnosed with PTSD or symptoms associated with Moral Injury. I then describe my own efforts investigating the connection between trauma and sustainability using survey measurements, interviews, and participant observation onsite at Growing Veterans farm in Mt. Vernon, Washington. The results strongly suggest that sustainable agricultural can be of powerful clinical benefit to traumatized veterans and that sustainable behaviors and values in general increased as trauma symptoms decreased. More broadly, the project indicates that slight shifts in how we approach solution formulation and how we articulate and disseminate sustainability messages could have profound positive effects on the sustainability’s success.
ContributorsGabriele, Adam (Author) / Hirt, Paul (Contributor) / Cloutier, Scott (Contributor) / Valdez, Herendira (Contributor)
Created2018-03-27
Description
An efficient thermal solver is available in the CMC that allows modeling self-heating in the electrical simulations, which treats phonons as flux and solves the energy balance equation to quantify thermal effects. Using this solver, thermal simulations were performed on GaN-HEMTs in order to test effect of gate architectures on the DC and RF performance of the device. A Π- gate geometry is found to suppress 19.75% more hot electrons corresponding to a DC power of 2.493 W/mm for Vgs = -0.6V (max transconductance) with respect to the initial T-gate. For the DC performance, the output current, Ids is nearly same for each device configuration over the entire bias range. For the RF performance, the current gain was evaluated over a frequency range 20 GHz to 120 GHz in each device for both thermal (including self-heating) and isothermal (without self-heating). The evaluated cutoff frequency is around 7% lower for the thermal case than the isothermal case. The simulated cutoff frequency closely follows the experimental cutoff frequency. The work was extended to the study of ultra-wide bandgap material (Diamond), where isotope effect causes major deterioration in thermal conductivity. In this case, bulk phonons are modeled as semiclassical particles solving the nonlinear Peierls - Boltzmann transport equation with a stochastic approach. Simulations were performed for 0.001% (ultra-pure), 0.1% and 1.07% isotope concentration (13C) of diamond, showing good agreement with the experimental values. Further investigation was performed on the effect of isotope on the dynamics of individual phonon branches, thermal conductivity and the mean free path, to identify the dominant phonon branch. Acoustic phonons are found to be the principal contributors to thermal conductivity across all isotope concentrations with transverse acoustic (TA2) branch is the dominant branch with a contribution of 40% at room temperature and 37% at 500K. Mean free path computations show the lower bound of device dimensions in order to obtain maximum thermal conductivity. At 300K, the lowest mean free path (which is attributed to Longitudinal Optical phonon) reduces from 24nm to 8 nm for isotope concentration of 0.001% and 1.07% respectively. Similarly, the maximum mean free path (which is attributed to Longitudinal Acoustic phonon) reduces from 4 µm to 3.1 µm, respectively, for the same isotope concentrations. Furthermore, PETSc (Portable, Extensible Toolkit for Scientific Computation) developed by Argonne National Lab, was included in the existing Cellular Monte Carlo device simulator as a Poisson solver to further extend the capability of the simulator. The validity of the solver was tested performing 2D and 3D simulations and the results were compared with the well-established multigrid Poisson solver.
ContributorsAcharjee, Joy (Author) / Saraniti, Marco (Thesis advisor) / Goodnick, Stephen (Committee member) / Thornton, Trevor (Committee member) / Wang, Robert (Committee member) / Arizona State University (Publisher)
Created2024