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The Negative Effects of Shared Leadership: An Application of Agent-Based Modeling Based on Lab Experiment Data
Get PDFRecently, there has been a surge of interest in the use of computational modeling (e.g., agent-based modeling, system dynamics, dynamic social networks) to study phenomena in the social sciences. Computational models have the advantage of being highly flexible, able to simulate complex interactions, succinctly capture nuanced theories into a set of clear governing rules, and reveal emergent macro-level phenomena from micro-level processes. Despite having decades of history in other fields of study (e.g., economics, epidemiology), these methods are novel and only just beginning to see applications in psychological research. In the present study, we demonstrate a novel application of agent-based modeling (ABM) using a hybrid approach, whereby data from a lab experiment are used to inform parameter values inputted into the ABM algorithms. These methods are demonstrated on the topic of shared leadership, a growing area of interest in leadership scholarship, with a focus on the potential “negative effects” of shared leadership that have been largely overlooked in decades of research. Reproducible free online code is provided for future scholars to modify and conduct their own simulation experiments. The results show how the ABM methods provide evidence in support of our proposed conceptual model of the “dark side” of shared leadership and offer an example of how ABM methods can be integrated into traditional psychological research
Interoperability in Environmental Modeling: Systems, Data, and Applications
Get PDFThe state of the science for flood risk management and the state of the practice in flood hazards engineering are in a period of transition. This transition is punctuated by the availability of high-resolution geospatial data and orders of magnitude increase in the resultant digital output as probabilistic and multi-epoch, multi-frequency analyses generate many terabytes of flood risk data. Once the domain of the personal computer, flood modeling activities are increasingly executed on the commercial cloud, leveraging distributed systems and serverless architecture to manage thousands of simultaneous simulations and process derivative products. The increased scale and complexity resulting from these changes presents new challenges in systems and data management. These challenges are exacerbated by the differences in nomenclature, tools, and data formats preferred by the many domain scientists performing environmental modeling in the development of flood hazards analysis. In this dissertation, we investigate and evaluate interoperability in systems for use in cross-domain collaboration. Existing and proposed standards are reviewed, and real-world case studies performed, in partnership with federal and state government agencies to explore challenges and identify solutions for managing large scale flood modeling campaigns in the cloud. Results include new computational frameworks for managing data, metadata, modeling, and analysis. The proposed frameworks and open source tools developed in the early investigations are then used operationally to explore the application of stochastic storm transposition (SST) in cold mountain regions of the western United States unserved by NOAA Altas 14 estimates of precipitation frequency data. This first known application of SST in flood prone areas dominated by snowmelt presents pioneering research and methods for developing frequency-based discharge estimates in a large, highly regulated watershed. Outcomes of this study include methods for capturing aleatory and epistemic uncertainty, and recommendations for future study in this field. Evaluating computational systems through the lens of interoperability, this work offers a domain agnostic vision for enhancing environmental modeling and designing cloud-based frameworks to support flood hazards analysis
Ground-based Light Curve Follow-up Validation observations of TESS object of interest TOI 5147.01
Get PDF“Exoplanet research is essential for understanding how planetary systems fit into our universe. Through the Transiting Exoplanet Survey Satellite (TESS) mission, many exoplanet candidates were found, but few have been confirmed. The purpose of this paper is to verify the existence of TESS Object of Interest (TOI) 5147.01 using the transit method. We took ground-based observations at George Mason University of the host star, TOI 5147, then created a light curve using AstroImageJ. A nearby eclipsing binary (NEB) check was conducted using AstroImageJ to analyze stars within a 2.5” of the host star. This is then followed by a Markov chain Monte Carlo (MCMC) analysis to calculate output parameters and their uncertainties. The AIJ lightcurve provides strong evidence for the existence of TOI 5147.01. However, there are still uncertainties for the transit timing and planet parameters for TOI 5147.01.
Constructing the Tago ng Tago: Examining the Intersections of Undocumented Filipinos, Neoliberalism, and Immigration Policy in Network Television
Get PDFThis thesis examines the nine-year precedent of undocumented Filipino series regulars on network television and the messaging they provide to audiences about undocumented life, Filipino identity, and current neoliberal immigration policy. These undocumented Filipino characters – Mateo Liwanag from NBC’s Superstore, and Thony De La Rosa and Fiona La Rosa from Fox’s The Cleaning Lady – offer audiences and scholars new understandings of undocumented peoples and current outlooks on immigration. In conducting an analysis of networks, genre, and character utilizing Stuart Hall’s model of encoding/decoding this thesis examines the impact of these characters in the cultural understanding of immigration and immigrants within the United States. By exploring the characters multiple identities, interactions with law enforcement and immigration policy, their role as Filipino workers, and pre-existing scholarship this thesis argues that these characters and their narratives challenge industry standards for undocumented character development and signal a shift away from the characterization of worthy and unworthy immigrants. Their narratives create critiques of current neoliberal immigration policies and transcend the categories of good/bad depictions, highlighting the messy and complicated nature of nuanced depictions. Moreover, their engagement with labor challenges harmful tropes of the “great Filipino worker”, which has historically been used to disempower Filipino laborers
Ground-based Light Curve Follow-up Validation observations of TESS object of interest TOI 3945.01
Get PDF“Transiting exoplanet survey satellite (TESS) is the leading discoverer of exoplanets using the transit method. As TESS reports any potential exoplanet candidates, follow-up observations are necessary to determine the identity of the TESS object of interest (TOI). In this paper, we aimed to confirm if the transit on TOI-3945.01 occurred between the predicted ingress and egress time, duration, and depth. Additionally, we attempted to investigate the planet type of TOI-3945.01 based on its properties. The data was gathered at the George Mason University (GMU) observatory using an R filter, obtaining 199 sciences each with 90 seconds of exposure. We performed data reduction, light curve production, and NEB check using AstroimageJ. Our light curve of TOI-3945.01 displayed slight dips in flux corresponding to the light curve generated by TESS, suggesting the likelihood that our target is a real positive. The NEB analysis did not show any definitive results, leaving potential signal disruption from NEB’s unknown. Further investigations with detailed statistical analyses are essential to establish a thorough conclusion regarding TOI-3945.01’s identity.
Computation of Dynamical Structures for Dynamical Billiards and Parameter Drift Equations
No full textIn this dissertation, we will be looking at computational methods for studying area preserving maps. We will demonstrate a new computational method for computing billiard maps, apply existing methods such as the weighted Birkho↵ average (WBA) to the billiards system, and construct a way to compute the stable and unstable manifolds by way of the parametrization method. Other methods have been used to compute the billiard map for convex tables but we have constructed a new method that is analytic and can work implicitly with the parametrized form of the ellipse. The parametrized form for the ellipse allows one to easily perturb the ellipse in a way that mimics the Fourier series which becomes more useful with the parametrization method. Previously, WBA and the parametrization method have been used on explicit systems but we will develop a novel method of applying them to an implicit form for the billiard map. This research is related to the Birkho↵ conjecture since our focus will be on billiard tables that are perturbations of the ellipse. In the second part of this dissertation, we will focus on applying the method of weighted Birkho↵ averages to parameter drift problems to study the breakup of tori. In particular, we will look at the periodically forced Dung oscillator and show how using the method ofweighted Birkho↵ averages speeds up this process and allows for quicker measurements of break up probabilities
Inhibitors of Ubiquitin Signaling Pathways Exhibit Antiviral Activities against Venezuelan Equine Encephalitis Virus
Get PDFAcutely infectious viruses including alphaviruses, Venezuelan equine encephalitis virus (VEEV) is vector transmitted, resulting in increased disease burden in the civilian and military population. Several of these pathogens are highly infectious and transmissible as aerosols, thus posing an increased threat as a potential bioweapon. Studies from GMU-CIDR laboratory and from several others have demonstrated the critical role of the host ubiquitination pathway in the establishment of a productive infection for acutely infectious viral agents. For example, it has been demonstrated that proteasome inhibitor Bortezomib was a broad-spectrum inhibitor of alphaviruses and bunyaviruses. Published studies have demonstrated that many viral proteins including the capsid protein of VEEV, the NS1, 3, and 5 proteins of Dengue Virus, VP35 protein of Ebola virus are ubiquitinated in infected cells. As part of efforts to characterize the host: viral protein interactome of alphaviruses using VEEV, we have identified several proteins involved in the ubiquitin-proteasome pathway as interacting with all the viral nonstructural proteins. These observations and evidence in the scientific literature prompted us to hypothesize that ubiquitin-proteasome inhibitors will constitute an excellent broad-spectrum strategy to address emerging/re-emerging viral challenges. As several viral proteins are known to be ubiquitinated in multiple sites, inhibiting such a broadly critical post-translational modification event is highly unlikely to result in resistant viruses. We examined multiple inhibitors of host signaling pathways using Venezuelan Equine Encephalitis Virus as a prototype pathogen. Of eight inhibitors that were tested for antiviral activities against the TC-83 strain of VEEV in three different cell lines (Vero, HMC3, and SVG-p12), NSC697923, Bardoxolone methyl (BARM), Omavelexelone (OMA) demonstrated robust inhibition of TC-83 at 1μM concentration. In vitro dosing studies conducted thus far have quantified viral loads following combined pre/post-treatment of cells, pre-treatment only, and post-treatment only conditions. The results identify combined pre/post-treatment as the most effective strategy in robustly reducing viral load between 2-4 logs
The High School Trombone Ensemble: Exploring its Pedagogical Value and Establishing Guidelines for Accessible Repertoire
Get PDFTrombone ensembles are common amongst most collegiate music schools and conservatories. Many play a central role in the trombone studio and even provide credit towards degree completion. Despite their growing popularity, however, trombone ensembles are not commonly seen in high school band programs. While a select few high schools offer such an ensemble, they are certainly the exception. Is this a missed opportunity for band directors and trombone teachers to provide a valuable platform for high school trombone students to learn and grow musically? Does the trombone ensemble provide significant and unique benefits for high school students and their band programs as it does for college students? Are the challenges posed by starting and running such a group outweighed by the educational value it provides students, and is there music in the repertoire that is appropriate for this level? There is a significant body of research dedicated to collegiate trombone ensembles, and plenty of discourse on high school small ensembles and chamber ensembles. I will examine both subsets of research, and draw from my own experience directing a high school trombone ensemble in order to show that the trombone ensemble can provide an invaluable and unique educational opportunity for high school students and their band programs. I will also examine three pieces in the trombone ensemble repertoire in order to demonstrate what characteristics make a piece both valuable from a pedagogical perspective, and accessible for a high school level trombone ensemble. One of these pieces is a new commission written by Canadian composer Elizabeth Raum for the Robinson Secondary School Trombone Choir, (of which I am the director)
Coach-Created Motivational Climate and Youth Soccer Player Self-Efficacy and Self-Talk
Get PDFYouth sports offer children a learning environment that can promote beneficial developmental experiences. Examples of these experiences include safe conditions for physical play with their peers, emotional maturation via executive functioning, and behavioral responses such as effort and concentration. The purpose of this study is to examine the relation between player perception of the coach-created motivational climate and player self-efficacy and usage of self-talk. Motivational climates are an inherent aspect of the psychological environment created by social agents that contribute to the athletic achievement-related experiences of the participants. For this thesis, participants were recruited from Vienna Youth Soccer, a non-profit soccer organization, and were aged between 10-13 years old. A total of 67 parents and players completed the survey with the average age of players being 11.55 years (SD =1.11). Participants completed the survey which measured player perceptions of the coach-created motivational climate, soccer self-efficacy, and self-talk use. The hypotheses included; players perceiving more of an ego-oriented motivational climate would have lower self-efficacy; players perceiving more of an ego-oriented motivational climate would use more negative selftalk; players who use much positive self-talk would have higher soccer self-efficacy; players with low self-efficacy and/or high in negative self-talk would show less interest in continuing to play soccer in future seasons; perception of motivational climate would be similar between the House and Travel soccer programs. Findings from correlational and multiple regression analyses revealed several significant relations between the variables but most of the hypotheses were not supported. Significant correlations were found between self-efficacy and three self-talk dimensions: motivational self-talk, positive self-talk, and negative self-talk. Females rated a higher perception of ego-oriented motivational climate and used less negative self-talk compared to males. White participants had higher levels of soccer self-efficacy that non-White participants. The child's own mastery-oriented motivation was marginally correlated with self-efficacy. Players who used much positive self-talk also used a lot of motivational and cognitive self-talk. Players use of self-talk was related to how much their coach encouraged them to use self-talk. Boys expected to continue longer in soccer than girls. There were no differences in motivational climate, self-efficacy, and self-talk use between the House and Travel players. The results from the multiple regressions controlling for race, gender, program type and age, however, indicated there no significant relationships between perception of coach motivational climate and soccer self-efficacy, motivational climate and use of selfx talk, nor between player self-efficacy and self-talk. The limited results might be explained by the small sample size and relatively low internal consistency reliability scores on a few of the measures. Coaches and soccer clubs should continue to be mindful of how they create their soccer environments and further research is needed
First-Generation Women of the African Diaspora Collective: Finding Fullness Through (Re)membering, an Endarkened Feminist Participatory Action Research Project
No full textThis work is embargoed by the author and will not be publicly available until May 2028.In the midst of a global pandemic and during a time of emboldened white supremacy, a group of women of the African diaspora created a collective to examine our experiences as first-generation college students navigating college. What started off as a conversation about the ways in which Black women’s voices are often silenced in the academy through misogynoir, developed into our search for fullness through the act of (re)membering. Together as a collective, 22 undergraduate and graduate first-generation women of the African diaspora (FGWAD) represented a wide range of the transnational African diaspora (Black, African American, African, Afro-Caribbean, Afro-Cuban, and Afro-Latina), having allegiances to multiple nation states ranging in age from early 20s to mid-50s. Engaging in the three-manuscript format method, this project examined the impact of systemic racism in higher education and explored our intersectional identities as first-generation college students. The author realized early on that the power of this research collective was not only to discover the impact of social injustice in the academy but also revealed a Black woman’s way of knowing. Along our journey for clarity, we created an endarkened feminist participatory research methodological approach (Collins, 1990; Cooper, 1892; Dillard, 2000; Drame & Irby, 2016). Black participatory research informed our work and members of the collective took part in each aspect of the research process, including research design, collection of data, analysis of data, establishment of findings, and their meaning. Each of these manuscripts were concerned with the larger implications of deficit-based ideologies, systemic oppressive structures that maintain power, and the collective grappling with complex and messy binary constructs such as race/gender, superhuman/ subhuman, and trauma/resilience. While co-researchers conversed about the ways in which the academy was suspicious of their stories, members of the collective came to trust and honor their complex and multiple truths through our collective storytelling. For example, the research demonstrated that FGWAD were expected to exhibit strength and exceptionality. On one hand, strong Black woman or Black girl magic ideas created a specific type of capital to navigate the university space or exceed their ancestors’ wildest dreams (Nell & Dunn, 2020), but on the other hand, it was also the site of great pain as members of the collective were expected to maintain excellence at all costs. This research project sought to transcend Black women’s experiences in which their knowledge was questioned, misunderstood, and oftentimes disrupted. Not only is this work significant to sabotage normative claims around research and knowledge, but it is also important in creating a new trajectory for future research.2028-05-1