Matching Items (262)
Description
In most of the work using event-related potentials (ERPs), researchers presume the function of specific components based on the careful manipulation of experimental factors, but rarely report direct evidence supporting a relationship between the neural signal and other outcomes. Perhaps most troubling is the lack of evidence that ERPs correlate with related behavioral outcomes which should result, at least in part, from the neural processes that ERPs capture. One such example is the NoGo-N2 component, an ERP component elicited in Go/NoGo paradigms. There are two primary theories regarding the functional significance of this component in this context: that the signal represents response inhibition and that the component reflects conflict. In this paper, a trial-level method of analysis for the relationship between ERP component potentials and downstream behavioral outcomes (in this case, response accuracy) using a multi-level modeling framework is proposed to provide discriminatory evidence for one of these theories. Following a description of the research on the NoGo-N2, preliminary data supporting the conflict monitoring theory are presented, noting important limitations. Next, an EEG simulation study is presented in which NoGo-N2 data are generated with a known relationship to fabricated reaction time data, showing that, with added levels of complexity and noise within the data, the MLM approach is consistently successful at extracting the known relationships that occur in real NoGo-N2 data. Next, using independent components analysis (ICA) to extract spatiotemporal components that best represent the signal of interest, a well-powered analysis of the relationship between the NoGo-N2 and response accuracy is used to provide strong discriminatory evidence for the conflict monitoring theory of the NoGo-N2. Finally, implications for the NoGo-N2, as well as all ERP components, are discussed with a focus on how this approach can and should be used. the paper concludes with potential expansions of this approach to areas beyond identifying the function of ERP components.
ContributorsHampton, Ryan Scott (Author) / Varnum, Michael E.W. (Thesis advisor) / Shiota, Michelle N. (Committee member) / Brewer, Gene A. (Committee member) / Blais, Chris (Committee member) / Arizona State University (Publisher)
Created2019
Description
Turbidity is a known problem for UV water treatment systems as suspended particles can shield contaminants from the UV radiation. UV systems that utilize a reflective radiation chamber may be able to decrease the impact of turbidity on the efficacy of the system. The purpose of this study was to determine how kaolin clay and gram flour turbidity affects inactivation of Escherichia coli (E. coli) when using a UV system with a reflective chamber. Both sources of turbidity were shown to reduce the inactivation of E. coli with increasing concentrations. Overall, it was shown that increasing kaolin clay turbidity had a consistent effect on reducing UV inactivation across UV doses. Log inactivation was reduced by 1.48 log for the low UV dose and it was reduced by at least 1.31 log for the low UV dose. Gram flour had a similar effect to the clay at the lower UV dose, reducing log inactivation by 1.58 log. At the high UV dose, there was no change in UV inactivation with an increase in turbidity. In conclusion, turbidity has a significant impact on the efficacy of UV disinfection. Therefore, removing turbidity from water is an essential process to enhance UV efficiency for the disinfection of microbial pathogens.
ContributorsMalladi, Rohith (Author) / Abbaszadegan, Morteza (Thesis director) / Alum, Absar (Committee member) / Fox, Peter (Committee member) / School of Human Evolution & Social Change (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
Accurately predicting local ranges of isotopic signatures in human populations is essential for answering questions about past migrations and mobility. While local ranges of δ18O can be estimated using modern baseline samples and precipitation models, there are many environmental and anthropogenic drivers that can cause these ranges to deviate from the ranges seen in human populations. This study performs a geostatistical meta-analysis on a large dataset (n = 1,370) of spatially contextualized archaeological δ18O samples from 30 publications in order to generate a predictive model of local human δ18O ranges in the Central Andes. Two models were generated, one using archaeological samples of both humans and fauna, and the other using only humans. The model using only human samples makes more accurate predictions, cautioning against the incorporation of faunal δ18O samples in studies of human provenance. The models are also compared against a model of δ18O values found in precipitation across the study area, and significant differences lead to the conclusion that precipitation models are insufficient for predicting local human δ18O ranges.
ContributorsHatley, Camden Miller (Author) / Knudson, Kelly (Thesis director) / Scaffidi, Beth (Committee member) / School of Earth and Space Exploration (Contributor) / School of Human Evolution & Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
This study evaluates medical pluralism among 1.5 generation Indian American immigrants. 1.5 generation Indian Americans (N=16) were surveyed regarding their engagement in complementary and alternative medical systems (CAM), how immigration affected that, and reasons for and for not continuing the use of CAM. Results indicated most 1.5 Indian immigrants currently engage in CAM, given that their parents also engage in CAM. The top reasons respondents indicated continued engagement in CAM was that it has no side effects and is preventative. Reasons for not practicing CAM included feeling out of place, not living with parents or not believing in CAM. After immigration, most participants decreased or stopped their engagement in CAM. More women than men continued to practice CAM after immigration. From the results, it was concluded that CAM is still important to 1.5 generation Indian immigrants.
ContributorsMurugesh, Subhiksha (Author) / Stotts, Rhian (Thesis director) / Mubayi, Anuj (Committee member) / School of Human Evolution & Social Change (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2020-05
Description
In everyday life, mental fatigue can be detrimental across many domains including driving, learning, and working. Given the importance of understanding and accounting for the deleterious effects of mental fatigue on behavior, a growing body of literature has studied the role of executive control processes in mental fatigue. In a laboratory setup, participants complete a task that places demands on executive control processes and are later given a transfer task. Generally speaking, decrements to subsequent task performance are taken as evidence that the initial executive control task created mental fatigue through the continued engagement of executive control. Several hypotheses have been developed to account for negative transfer resulting from executive control depletion including cognitive resource depletion and task-switching. In the current study, we provide a brief literature review, specify current theoretical approaches to depletion, and provide a strong empirical test of theories for negative transfer from executive control depletion (i.e., does continued performance of an executive control task negatively transfer to that exact same task).
ContributorsLau, Kin Hang (Author) / Brewer, Gene (Thesis director) / Knight, George (Committee member) / Blais, Chris (Committee member) / Barrett, The Honors College (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Department of Psychology (Contributor)
Created2014-12
Effects of Assisted Cycle Therapy on Short Term and Working Memory in Adolescents with Down Syndrome
Description
To examine the effect of an 8-week cycling intervention on short term and working memory in adolescents with Down syndrome (DS), participants were divided into Assisted Cycling Therapy (ACT), Voluntary Cycling (VC), or No Cycling (NC) groups. Forward and backward digit span assessments were administered prior to and after the intervention to evaluate short term and working memory respectively. 8 weeks of exercise via ACT showed a trend toward conventional levels of significance in the number of levels completed in the backward direction.
ContributorsSandoval-Menendez, Amber Melanie (Author) / Ringenbach, Shannon (Thesis director) / Amazeen, Eric (Committee member) / Blais, Chris (Committee member) / Barrett, The Honors College (Contributor) / School of Nutrition and Health Promotion (Contributor)
Created2015-05
Description
Forced pregnancy has been and remains a tactic of implementing genocide and inflicting long-lasting damage on a population. Forced marriages during the Cambodian genocide (1975-1979) and rape camps established during the Bosnian genocide (1992-1995) are two of many ways in which forced pregnancies can be implemented. This comparative study has identified social constructs within Bosnian and Cambodian cultures that allowed forced pregnancy to impact these populations. In the context of the Cambodian genocide, the Khmer Rouge implemented forced marriages in order to reproduce an agricultural labor force that would sustain the state of Democratic Kampuchea without foreign aid. The cultural construct of marriage promoted childbearing and sustained these marriages even after the fall of the Khmer Rouge regime. The Bosnian genocide, on the other hand, was an ethnic cleansing against Bosnian Muslims. Serbian forces established rape camps to impregnate Bosnian Muslim women in order to stigmatize them to the extent that they would (culturally) no longer be able to bear children for their own ethnic community. The cultural constructs of virginity and patrilineal descent acted as key factors in the effectiveness of forced pregnancy as a method of ethnic cleansing. While Bosnian Muslim rape camp survivors faced stigma for having been raped and for keeping their children if they chose to, Cambodian survivors would not. Cambodian women faced social expectations to stay in their marriages and keep their children in order to fulfill their duties as wives and mothers. In Bosnia, however, no social construct existed to support children born outside of marriage. In addition to these cultural constructs, various other factors influenced survivors' attitudes towards their children, including the presence of third party rapists in the Cambodian genocide and the fact that many Bosnian Muslim survivors did not know the identity of the father of their children. Comparative analysis of these two genocides has contributed to a more holistic understanding of the impacts of genocide and has informed how forced pregnancy operates across multiple cultural ideologies and lifestyles.
ContributorsVirdee, Tajinder (Author) / Holman, Christine (Thesis director) / Toth, Stephen (Committee member) / School of Human Evolution & Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description
The purpose of this research study was to examine the intersection of the relationship between homelessness and mental illness, including other factors such as substance abuse. A secondary purpose of this study was to gain an awareness of service delivery models and associated funding streams for providing services to homeless persons with mental illness. A thorough literature review was conducted by the author in order to aid in answering these questions. The author also conducted interviews with 27 homeless and formerly homeless clients living in Denver who were receiving services through the Colorado Coalition for the Homeless. Finally, the author conducted 4 qualitative interviews with policy experts who worked extensively in homeless services and advocacy in the Metro-Denver area. All data was entered into an Excel workbook, and a series of graphs and tables were made to present the research results. The themes of mental illness and substance abuse were common amongst the sample population, but the most common theme was that of the lack of affordable housing available. The majority of respondents also cited involvement in the criminal justice system such as incarceration, as well as family issues as major factors in them becoming homeless. The policy experts all cited the Housing First as well as the Permanent Supportive Housing model as the most effective service delivery model for those who are both homeless and mentally-ill, and Denver is utilizing some very innovative funding streams for these service delivery models. In conclusion, the author found through both the literature review and quantitative research, that homelessness is not truly a mental illness or substance abuse issue alone, though this relationship does hold clinical importance. Homelessness is instead the result of an excessive shortage of permanent and affordable housing units across the United States.
ContributorsNelson, Hunter Lee (Author) / Shafer, Michael (Thesis director) / Ferguson-Colvin, Kristin (Committee member) / School of Community Resources and Development (Contributor) / School of Human Evolution & Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2018-12
Description
Every minute and a half, an American is sexually assaulted (Department of Justice, 2017). After an instance of sexual assault, some victims are given the choice of having a sexual assault evidence kit (SAK) collected. These kits are designed to collect DNA evidence that will, in the best case scenario, result in the identification of the perpetrator. If the perpetrator cannot be located, the DNA profile can still be submitted to the FBI’s CODIS databank, which houses hundreds of thousands of DNA profiles from criminal cases, and may still lead to apprehension of the rapist. Unfortunately, some SAKs experience long delays, decades even, before being tested. To date, there are hundreds of thousands of untested SAKs that remain in police custody awaiting to be submitted for forensic profiling across the country. Here, we completed a holistic investigation of sexual assault response and SAK processing in Arizona. It is important to notice that the focus of our study not only includes SAK processing and the backlog but sexual assault prevention and improving victim reporting in an effort to understand the SAK “pipeline,” from assault to prosecution.
We identified problems in three major categories that negatively impact the SAK pipeline: historical inertia, legislative and institutional limitations, and community awareness. We found that a large number of SAKs in Arizona have remained untested due insufficient funding and staffing for public crime labs making it difficult for state labs to alleviate the SAK backlog while simultaneously responding to incoming cases (“Why the Backlog Exists,” n.d.). However, surveys of ASU undergraduate students revealed a significant interest in campus assault and the SAK backlog. Based on our findings, we suggest harnessing the interest of undergraduate students and recruiting them to specialized SAK-oriented forensic technician and sexual assault nurse examiner (SANE) training at ASU with the goal of creating a workforce that will alleviate the absence of trained professionals within the country. We also explore the possibility of the creation of a private crime laboratory at ASU devoted the processing of SAKs in Arizona as a measure of alleviating the demand on local public laboratories and providing a more economic alternative to commercial laboratories. The creation of an SAK laboratory at ASU would provide undergraduates the opportunity to learn more about real forensic analysis on campus, provide a pipeline for students to become technicians themselves, and help reduce and prevent a future SAK backlog in Arizona.
We identified problems in three major categories that negatively impact the SAK pipeline: historical inertia, legislative and institutional limitations, and community awareness. We found that a large number of SAKs in Arizona have remained untested due insufficient funding and staffing for public crime labs making it difficult for state labs to alleviate the SAK backlog while simultaneously responding to incoming cases (“Why the Backlog Exists,” n.d.). However, surveys of ASU undergraduate students revealed a significant interest in campus assault and the SAK backlog. Based on our findings, we suggest harnessing the interest of undergraduate students and recruiting them to specialized SAK-oriented forensic technician and sexual assault nurse examiner (SANE) training at ASU with the goal of creating a workforce that will alleviate the absence of trained professionals within the country. We also explore the possibility of the creation of a private crime laboratory at ASU devoted the processing of SAKs in Arizona as a measure of alleviating the demand on local public laboratories and providing a more economic alternative to commercial laboratories. The creation of an SAK laboratory at ASU would provide undergraduates the opportunity to learn more about real forensic analysis on campus, provide a pipeline for students to become technicians themselves, and help reduce and prevent a future SAK backlog in Arizona.
ContributorsStewart, Jamie (Co-author) / Brokaw, Danielle (Co-author) / Stone, Megan (Co-author) / Kanthaswamy, Sreetharan (Thesis director) / Oldt, Robert (Committee member) / School of Human Evolution & Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Growing hotspots of unvaccinated children corroborate with states that have highly permissive vaccination policies. State-based nonmedical exemption (NME) policies such as religious or philosophical exemptions make it easy for parents to opt out of vaccinating their children thus lowering herd immunity and increasing the risk of outbreaks. Recent studies have revealed that Phoenix is the metropolitan area with the highest number of nonmedical exemptions in the country with vaccination rates below herd immunity. This thesis investigates the role of the law in enabling low vaccination rates and develops a set of policy recommendations that lawmakers may use as a tool to restore these rates to herd immunity levels. To do this, an in-depth literature review was performed and supplemented with a case study of California’s policy response to the 2014 Disneyland measles outbreak. This information was synthesized into an in-depth policy analysis addressing the political, social, practical, and economic factors of the issue and four potential policy responses for state lawmakers. Based on the analysis and California’s example, eliminating nonmedical vaccine exemptions was identified as the most effective policy option to reach the intended goal of restoring vaccination rates to herd immunity levels. This policy option is both the most cost-effective and productive in reaching herd immunity but infringes the most on parental rights and will be met with the most significant political pushback. Despite these challenges, lawmakers should take this policy step to protect our community and the most vulnerable among us.
ContributorsSaxon, Mary Elizabeth (Author) / Reddy, Swapna (Thesis director) / Speer, Matthew (Committee member) / School of Human Evolution & Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05