Matching Items (83)
Description
This dissertation investigates the condition of skeletal muscle insulin resistance using bioinformatics and computational biology approaches. Drawing from several studies and numerous data sources, I have attempted to uncover molecular mechanisms at multiple levels. From the detailed atomistic simulations of a single protein, to datamining approaches applied at the systems biology level, I provide new targets to explore for the research community. Furthermore I present a new online web resource that unifies various bioinformatics databases to enable discovery of relevant features in 3D protein structures.
ContributorsMielke, Clinton (Author) / Mandarino, Lawrence (Committee member) / LaBaer, Joshua (Committee member) / Magee, D. Mitchell (Committee member) / Dinu, Valentin (Committee member) / Willis, Wayne (Committee member) / Arizona State University (Publisher)
Created2013
Description
While exercising mammalian muscle increasingly relies on carbohydrates for fuel as aerobic exercise intensity rises above the moderate range, flying birds are extraordinary endurance athletes and fuel flight, a moderate-high intensity exercise, almost exclusively with lipid. In addition, Aves have long lifespans compared to weight-matched mammals. As skeletal muscle mitochondria account for the majority of oxygen consumption during aerobic exercise, the primary goal was to investigate differences in isolated muscle mitochondria between these species and to examine to what extent factors intrinsic to mitochondria may account for the behavior observed in the intact tissue and whole organism. First, maximal enzyme activities were assessed in sparrow and rat mitochondria. Citrate synthase and aspartate aminotransferase activity were higher in sparrow compared to rat mitochondria, while glutamate dehydrogenase activity was lower. Sparrow mitochondrial NAD-linked isocitrate dehydrogenase activity was dependent on phosphate, unlike the mammalian enzyme. Next, the rate of oxygen consumption (JO), electron transport chain (ETC) activity, and reactive oxygen species (ROS) production were assessed in intact mitochondria. Maximal rates of fat oxidation were lower than for carbohydrate in rat but not sparrow mitochondria. ETC activity was higher in sparrows, but no differences were found in ROS production between species. Finally, fuel selection and control of respiration at three rates between rest and maximum were assessed. Mitochondrial fuel oxidation and selection mirrored that of the whole body; in rat mitochondria the reliance on carbohydrate increased as the rate of oxygen consumption increased, whereas fat dominated under all conditions in the sparrow. These data indicate fuel selection, at least in part, can be modulated at the level of the mitochondrial matrix when multiple substrates are present at saturating levels. As an increase in matrix oxidation-reduction potential has been linked to a suppression of fat oxidation and high ROS production, the high ETC activity relative to dehydrogenase activity in avian compared to mammalian mitochondria may result in lower matrix oxidation-reduction potential, allowing fatty acid oxidation to proceed while also resulting in low ROS production in vivo.
ContributorsKuzmiak, Sarah (Author) / Willis, Wayne T (Thesis advisor) / Mandarino, Lawrence (Committee member) / Sweazea, Karen (Committee member) / Harrison, Jon (Committee member) / Gadau, Juergen (Committee member) / Arizona State University (Publisher)
Created2012
Description
Critical flicker fusion thresholds (CFFTs) describe when quick amplitude modulations of a light source become undetectable as the frequency of the modulation increases and are thought to underlie a number of visual processing skills, including reading. Here, we compare the impact of two vision-training approaches, one involving contrast sensitivity training and the other directional dot-motion training, compared to an active control group trained on Sudoku. The three training paradigms were compared on their effectiveness for altering CFFT. Directional dot-motion and contrast sensitivity training resulted in significant improvement in CFFT, while the Sudoku group did not yield significant improvement. This finding indicates that dot-motion and contrast sensitivity training similarly transfer to effect changes in CFFT. The results, combined with prior research linking CFFT to high-order cognitive processes such as reading ability, and studies showing positive impact of both dot-motion and contrast sensitivity training in reading, provide a possible mechanistic link of how these different training approaches impact reading abilities.
ContributorsZhou, Tianyou (Author) / Nanez, Jose (Author) / Zimmerman, Daniel (Author) / Holloway, Steven (Author) / Seitz, Aaron (Author) / New College of Interdisciplinary Arts and Sciences (Contributor)
Created2016-10-26
Description
Although autism spectrum disorder (ASD) is a serious lifelong condition, its underlying neural mechanism remains unclear. Recently, neuroimaging-based classifiers for ASD and typically developed (TD) individuals were developed to identify the abnormality of functional connections (FCs). Due to over-fitting and interferential effects of varying measurement conditions and demographic distributions, no classifiers have been strictly validated for independent cohorts. Here we overcome these difficulties by developing a novel machine-learning algorithm that identifies a small number of FCs that separates ASD versus TD. The classifier achieves high accuracy for a Japanese discovery cohort and demonstrates a remarkable degree of generalization for two independent validation cohorts in the USA and Japan. The developed ASD classifier does not distinguish individuals with major depressive disorder and attention-deficit hyperactivity disorder from their controls but moderately distinguishes patients with schizophrenia from their controls. The results leave open the viable possibility of exploring neuroimaging-based dimensions quantifying the multiple-disorder spectrum.
ContributorsYahata, Noriaki (Author) / Morimoto, Jun (Author) / Hashimoto, Ryuichiro (Author) / Lisi, Giuseppe (Author) / Shibata, Kazuhisa (Author) / Kawakubo, Yuki (Author) / Kuwabara, Hitoshi (Author) / Kuroda, Miho (Author) / Yamada, Takashi (Author) / Megumi, Fukuda (Author) / Imamizu, Hiroshi (Author) / Nanez, Jose (Author) / Takahashi, Hidehiko (Author) / Okamoto, Yasumasa (Author) / Kasai, Kiyoto (Author) / Kato, Nobumasa (Author) / Sasaki, Yuka (Author) / Watanabe, Takeo (Author) / Kawato, Mitsuo (Author) / New College of Interdisciplinary Arts and Sciences (Contributor)
Created2016-04-14
Description
Creativity is a critical element of human cognition for which any complete explanation of the human mind must account, and it presents a unique problem to cognitive science because the apparent "something from nothing" nature of creativity confounds simple transformations of existing information. Emergentism provides a philosophical framework for explaining this feature of creativity by elaborating how novel properties of a system can be created from the complex interactions of simple elements within that system. Previous advances in cognitive science have been built the traditional information processing models of cognition. These models are limited in their ability to explain emergentism or allow for detailed behavioral measurement and understanding of cognition as it unfolds in time. In this study, I piloted the use state-of-the-art dynamical systems models of cognition and motion capture technology to measure information about cognitive and neural processes in the moments preceding creative insight. Insight problem solving refers to the phenomenon of experiencing an impasse when attempting to solve a problem that is later overcome in a flash of insight, sometimes called an "Aha!" or "Eureka!" moment. The use of these techniques to study insight problem solving provides evidence of the dynamical nature of cognition during creative tasks that may help us explore how creativity emerges from neural activity.
ContributorsHart Jr, John Thomas (Author) / Duran, Nicholas (Thesis director) / Nishimura, Joel (Committee member) / School of Social and Behavioral Sciences (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
Historically, Supreme Court interpretations of the Constitution of the United States have been significantly important, impacting the lives of every American. This honors thesis seeks to understand the ways in which the Constitution has been interpreted through the lens of political ideology. Using constitutional theory, I explain how the political ideologies of classical liberalism, conservatism, libertarianism, and progressive liberalism have played a role in the interpretations of the First, Second, and Fourth Amendments. I also examine how these ideological interpretations have changed from 1776 to 2017, dividing the history of the United States into four eras: the Founding Era, the Civil War Era, the New Deal Era, and the Modern Era. First, the First Amendment's clauses on religion are examined, where I focus on the separation between church and state as well as the concepts of "establishment" and "free exercise." The First Amendment transitions from classically liberal, to conservative, to progressively liberal and classically liberal, to progressively liberal and libertarian. Next, we look at the Second Amendment's notions of a "militia" and the "right to keep and bear arms." The Second Amendment's interpretations begin classically liberal, then change to classically liberal and progressively liberal, to progressively liberal, to conservative. Finally, the analysis on the Fourth Amendment's "unreasonable searches and seizures" as well as "warrants" lends evidence to ideological interpretations. The Fourth Amendment, like the other two, starts classically liberal for two eras, then becomes libertarian, and finally ends libertarian and conservative. The implications of each of these conclusions are then discussed, with emphasis on public opinion in society during the era in question, the ways in which the ideologies in each era seem to build upon one another, the ideologies of the justices who wrote the opinions, and the ideology of the court.
ContributorsSmith, Charlene Anne (Author) / Lennon, Tara (Thesis director) / Hudson, Jill (Committee member) / New College of Interdisciplinary Arts and Sciences (Contributor) / School of Criminology and Criminal Justice (Contributor) / School of Social and Behavioral Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2017-12
Description
Individuals with psychogenic non-epileptic seizures (PNES) show signs of emotion-related dysfunction and disrupted interpersonal relationships. Affectionate touch is an important form of non-verbal communication in relationships that may foster emotion regulation and emotional awareness. The present online survey study included 62 individuals with PNES and 80 seizure-free trauma-exposed controls high (n=40) or low (n=40) in overall symptoms of psychopathology. As hypothesized, PNES individuals reported experiencing less frequent affectionate touch and less interoceptive awareness than either control group. They also reported more somatic symptoms, more emotion regulation difficulties, and less positive emotion than the low psychopathology group. Unexpectedly, there were no group differences in emotional awareness difficulties, nor in initiation of affectionate touch. Across participants, lower interoceptive awareness was associated with lower affectionate touch frequency, indicating that if one has difficulty understanding and being aware of their own body, affectionate touch sensations may not necessarily be understood as pleasant and may be minimized or avoided. Emotional awareness difficulties surprisingly were associated with greater affectionate touch frequency among PNES (versus the expected pattern of awareness difficulties associated with less affectionate touch, as found among controls), suggesting affectionate touch may be used as an attempt to try and understand one’s own feelings, or to compensate for, or even mask a lack of understanding. Findings indicate a distinct difference in physical affection frequency and interoceptive awareness among PNES individuals even when matched to a group similar in psychiatric distress/psychopathology. These findings offer insight into the relationships between interoceptive awareness, affectionate touch, and emotion regulation more broadly.
ContributorsVillarreal, Lucia (Author) / Roberts, Nicole A (Thesis advisor) / Burleson, Mary H (Committee member) / Duran, Nicholas (Committee member) / Arizona State University (Publisher)
Created2021
Description
To reveal opinions people may not explicitly portray, researchers have implemented a methodology called the Implicit Associations Test (IAT). While this test saw widespread use after its inception, recent problems have undermined the reliability of the measure. Researchers have begun to address these limitations by evaluating different approaches, such as the Action Dynamics paradigm. Like the IAT, the aim of action dynamics is to assess underlying activation and competition amongst beliefs as they unfold in real-time, while adding a number of more sensitive measures, in addition to those used in an IAT. The trajectories of participants’ computer mouse cursors are tracked as they move from a stimulus statement to a response, providing data of the real-time decisions people are making across a number of variables. For this thesis study, the aim was to use an action dynamics paradigm to explore whether implicit biases exist toward transgender people from a larger cisgender population, even if they explicitly support or oppose others with transgender identities. These potential biases were assessed by evaluating the statements people were asked to confirm or disconfirm. There were also a number of analyses conducted in order to investigate whether such predictors such as
participants’ gender or political ideology predicted differences in responses. Although differences were seen in the reaction time to statements of a certain category, the other trajectory measures showed that participants’ implicit and explicit attitudes toward transgender people were aligned. Implications, limitations, and future directions of this
work are then discussed.
ContributorsHamlett, Mara Carol (Author) / Duran, Nicholas (Thesis advisor) / Mickelson, Kristin (Committee member) / Hall, Deborah (Committee member) / Arizona State University (Publisher)
Created2022
Description
Emotions are an important part of persuasion. Experimental research suggests that White and male jurors can use emotion to increase their influence, while other jurors cannot. This research builds on prior research by examining the relationship between naturally occurring emotion during mock jury deliberations and the influence that jurors hold. Participants (N = 708) in 153 mock juries watched a murder trial video and deliberated on a verdict. Participants self-reported their experienced emotions and rated their perceptions of the other jurors’ emotion and influence. After data was collected, I extracted acoustic indicators of expressed emotion from each deliberation and used a speech emotion recognition model to classify each mock juror’s emotional expression. I hypothesized that there would be an overall effect of emotional expression on influence such that as mock jurors’ emotion increased, their influence would also increase. However, I hypothesized that a juror’s race and gender would moderate the relationship between emotion and influence such that White male jurors will be seen as more influential when they are more emotional, and that female jurors and jurors of color will be seen as less influential when they are more emotional. I also hypothesized that female jurors of color will be doubly penalized for being emotional, due to their “double-minority” status. Bayesian model averaging suggested that the data was most probable under models that included perceived emotion, race, and the interaction between the two, compared to models that did not. Consistent with the hypothesis, as participants were perceived as more emotional, their influence increased. In contrast to the hypotheses, being perceived as more emotional increased influence for both White and non-White mock jurors but the effect was stronger for non-White jurors. In other words, while all jurors benefited from being perceived as more emotional, non-White jurors benefited more than White jurors. Male jurors were more influential than female jurors, and gender did not interact with emotion.. Although being perceived as more emotional predicted increased influence for all participants, this research demonstrates that there are racial and gender disparities in the level of influence that someone might hold on a jury.
ContributorsPhalen, Hannah J (Author) / Salerno, Jessica (Thesis advisor) / Schweitzer, Nicholas (Committee member) / Duran, Nicholas (Committee member) / Arizona State University (Publisher)
Created2023
Description
Behavioral, electrophysiological, and neuroimaging evidence has demonstrated that multiple object tracking (MOT) tasks draw upon visual perception, attention, and working memory cognitive processes. Functional neuroimaging studies identified the middle temporal visual area (MT+/V5) as one of several brain regions associated with MOT in humans. MT+/V5 is thought to be responsible for processing motion from visual information, regulating smooth pursuit eye movements, and encoding memory for motion. However, it is unclear how MT+/V5 interacts with attention and working memory performance processes during MOT. To investigate this question, the right MT+/V5 region was identified in 14 neurotypical subjects using structural magnetic resonance imaging (sMRI). The right MT+/V5 was stimulated using intermittent theta-burst stimulation (iTBS), continuous theta-burst stimulation (cTBS), and sham transcranial magnetic stimulation (TMS) using a within-subjects design. Average MOT performance was measured before and 5-min, 30-min, and 60-min after each stimulation protocol. There was no significant difference in average MOT performance across time, regardless of the stimulation condition.
ContributorsAlucard, Myles (Author) / Duran, Nicholas (Thesis advisor, Committee member) / Brewer, Gene (Thesis advisor, Committee member) / Burleson, Mary (Committee member) / Arizona State University (Publisher)
Created2023