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Title: The growth of organic small molecule and inorganic halide perovskite crystalline thin films
Creator: Chen, Pei (Graduate of Michigan State University)
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Organic semiconductors have shown exceptional opportunities for manipulating energy in a range of structures in light-emitting diodes, lasers, transistors, transparent photovoltaics, etc. with the presence of excitons at room temperature that distinguishes them from traditional semiconductors. The control over the crystalline order, orientation, layer-coupling as well as defect formation are the key to the fabrication and optimization for improving the performance of organic electronics. In...
Show moreOrganic semiconductors have shown exceptional opportunities for manipulating energy in a range of structures in light-emitting diodes, lasers, transistors, transparent photovoltaics, etc. with the presence of excitons at room temperature that distinguishes them from traditional semiconductors. The control over the crystalline order, orientation, layer-coupling as well as defect formation are the key to the fabrication and optimization for improving the performance of organic electronics. In the first part of this thesis, we focus on understanding organic crystalline growth. Organic homoepitaxy growth mode is mapped as a function of vapor phase growth conditions on high quality organic crystalline substrates. Organic-organic hetero-quasiepitaxy is then studied to explore the design rules for ordered alternating organic growth similar to inorganic quantum well structure. A unique organic edge driven case is demonstrated providing new routes to controlling molecular orientation and multilayer ordering. These results could enable entirely new opportunities for enhancing unique excitonic tunability and could also be used as a platform to study organic exciton confinement and strong coupling.The second part of the thesis is focused on inorganic halide perovskite growth. Hybrid halide perovskites have attracted tremendous attention as an exceptional new class of semiconductors for solar harvesting, light emission, lasing, quantum dots, thin-film electronics, etc. However, the toxicity of lead devices and lead manufacturing combined with the instability of organic components have been two key barriers to widespread applications. In this work, we demonstrate the first single-domain epitaxial growth of halide perovskites. This in situ growth study is enabled by the study of homoepitaxy and mixed-homoepitaxy of metal halide crystals that demonstrates the capability of performing reflection high-energy electron diffraction (RHEED) on insulating surfaces. We then focus on tin-based inorganic halide perovskites, CsSnX3 (X = Cl, Br, and I), on lattice-matched metal halide crystals via reactive vapor growth route that leads to single-domain epitaxial films with excellent crystalline order lacking in solution processing. Exploiting this highly controllable epitaxial growth we demonstrate the first halide perovskite quantum wells that creates photoluminescent tunability with different well width. These demonstrations could spark the exploration of a full range of epitaxial halide perovskites and lead to novel applications for metal-halide-perovskite based single-crystal epitaxial optoelectronics.
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Title: Evaluating blue courage : a national evaluation of the blue courage training program
Creator: Drake, Gregory M.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: The impact of stress on police officers has profound implications for both the wellness of individual officers and the legitimacy of policing as field. Stress produces a litany of negative impacts on officer health, including direct impacts like a higher risk of heart disease and a shorter life expectancy as well as indirect effects like an increased risk of the development of harmful coping mechanisms like substance abuse. More recently, the impacts of stress on individual officers have been...
Show moreThe impact of stress on police officers has profound implications for both the wellness of individual officers and the legitimacy of policing as field. Stress produces a litany of negative impacts on officer health, including direct impacts like a higher risk of heart disease and a shorter life expectancy as well as indirect effects like an increased risk of the development of harmful coping mechanisms like substance abuse. More recently, the impacts of stress on individual officers have been observed to spill over and negatively affect community-police relations as officers struggle to contain emotional responses when under stress or withdraw from critical functions of police work, like community engagement, as a way to manage stress.This study performed an evaluation of a holistic police training program called Blue Courage, which is designed to educate officers about the impact of stress and provide them with tools to improve the health and wellness of themselves and the profession writ large. This study was a mixed-methods process and outcome evaluation of the training program, and consisted of observations of the training, interviews with key program staff, and the use of a case study model to elucidate aspects of the Blue Courage train-the-trainer model of delivery. Additional, data from 681 training participants, collected between June of 2017 and September of 2018 was used to determine the impact of the training on a number of attitudes central to officer health and wellness. At the conclusion of this dissertation, discussions of the findings and future directions for research are discussed. Additionally, several policy recommendations for the Blue Courage organization are provided.
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Title: Connecting chemistry and biology : exploring students' perceptions of college courses
Creator: Kohn, Kathryn Paris
Date: 2018
Collection: Electronic Theses & Dissertations
Description: "This dissertation explores students' perceptions of their chemistry and biology courses through the lens of two crosscutting concepts, energy and the relationship between structure, properties, and function. Energy underlies all scientific phenomena. Structure-property and structure-function relationships have long been considered important explanatory concepts in the disciplines of chemistry and biology, respectively. As such, these crosscutting concepts provide an interesting context in...
Show more"This dissertation explores students' perceptions of their chemistry and biology courses through the lens of two crosscutting concepts, energy and the relationship between structure, properties, and function. Energy underlies all scientific phenomena. Structure-property and structure-function relationships have long been considered important explanatory concepts in the disciplines of chemistry and biology, respectively. As such, these crosscutting concepts provide an interesting context in which to investigate student connections and misconnections across disciplines."--from abstract.
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Title: The patriot and the traitor : defending your collective face in front of co-nationals and foreigners
Creator: Zhu, Yi (College teacher)
Date: 2019
Collection: Electronic Theses & Dissertations
Description: The current between-subjects study investigated how participants from two cultural groups (100 American domestic students and 115 Chinese international students) deal with threats to their collective face elicited from a critic who is either an ingroup member, an outgroup member, or an identity-unspecified member in an intercultural-communication context with a laboratory experimental design. Chinese students reported higher collective face concerns and lower liking towards a person who...
Show moreThe current between-subjects study investigated how participants from two cultural groups (100 American domestic students and 115 Chinese international students) deal with threats to their collective face elicited from a critic who is either an ingroup member, an outgroup member, or an identity-unspecified member in an intercultural-communication context with a laboratory experimental design. Chinese students reported higher collective face concerns and lower liking towards a person who criticized their collective face compared with Americans. While encountering criticism targeting their countries, Chinese felt higher discomfort feelings compared with Americans. Chinese participants' discomfort feelings in the ingroup-critic condition were more influenced by their collective face concerns compared with Americans in the same condition. The practical and methodological implications of this study were also discussed.
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Title: I don't get mad, I get even : emotions & betrayal responses in close relationships
Creator: Nelson, Joshua Charles
Date: 2019
Collection: Electronic Theses & Dissertations
Description: This study investigated the revenge process by identifying predictors of engagement in revenge behaviors within close relationships. Consisting of two parts, this study first used social exchange theory as a basis to test whether emotion management, feelings of anger and hurt, or tendency to forgive are associated with general revenge or relational restoration following a betrayal by a close relational partner. Findings suggested the only significant association with revenge is feelings of...
Show moreThis study investigated the revenge process by identifying predictors of engagement in revenge behaviors within close relationships. Consisting of two parts, this study first used social exchange theory as a basis to test whether emotion management, feelings of anger and hurt, or tendency to forgive are associated with general revenge or relational restoration following a betrayal by a close relational partner. Findings suggested the only significant association with revenge is feelings of anger. No variable showed a relationship with relational restoration. The second part of the study refined the first part by drawing from the theory of revenge process to test whether emotion management or tendency to forgive was associated with covert, overt, avoidant, and approaching revenge behaviors. No relationships were found between emotion management or tendency to forgive with any of the revenge behaviors described in the theory of revenge process. New directions for the study of revenge engagement are suggested.
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Title: Ferroelectret nanogenerator (FENG) for mechanical energy harvesting and self-powered flexible electronics
Creator: Li, Wei (Mechanical engineer)
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Harvesting energy from our natural environment has been the focus of multiple research efforts in the past decades. Progress in this field has far-reaching implications for the growing environment problems resulting from greenhouse gas emission of fossil fuels. Furthermore, advances in portable energy scavenging devices will shed light on the development of self-powered and autonomous electronics; which will impact a broad range of applications in wireless sensors, biomedical implants,...
Show moreHarvesting energy from our natural environment has been the focus of multiple research efforts in the past decades. Progress in this field has far-reaching implications for the growing environment problems resulting from greenhouse gas emission of fossil fuels. Furthermore, advances in portable energy scavenging devices will shed light on the development of self-powered and autonomous electronics; which will impact a broad range of applications in wireless sensors, biomedical implants, infrastructure monitoring, and portable/wearable electronics. This thesis research explores the designs, fabrications, simulations, characterizations and applications of flexible thin film nanogenerator based energy harvesting technologies. Materials and designs for flexible nanogenerator based on nanocrystalline aluminum nitride (AlN) thin film are reported. AlN nanoparticles were grown on aluminum layer by pulsed laser deposition (PLD) at room temperature. Piezoresponse force microscopy (PFM) indicates that their electromechanical energy conversion metrics are as high as highly c-axis oriented AlN or ZnO thin film. Polyimide thin film encapsulated the entire structure of flexible nanogenerator to further improve mechanical robustness, protecting the device from invasive chemicals and enhance its potential biocompaibility. Besides, this thesis research introduces polypropylene ferroelectret (PPFE) as the active material in an efficient, flexible, and biocompatible ferroelectret nanogenerator (FENG) device. PPFE is a type of charged polymers with empty voids and inorganic particles that create giant dipoles across the material's thickness. The mechanical-electrical energy conversion mechanism in PPFE films is verified by finite element method (FEM). Investigation of the developed device shows that the magnitudes of the generated voltage and current signals are doubled each time the device is folded, and an increase with magnitude or frequency of the mechanical input is observed. The developed FENGs is sufficient to light twenty commercial green and blue light-emitting diodes (LEDs), and realize a self-powered liquid-crystal display (LCD) that harvests energy from user's touch. A self-powered flexible/foldable keyboard is also demonstrated. Furthermore, this thesis reports the device's intrinsic properties which allow for the bi-directional conversion of energy between electrical and mechanical domains; thus extending its potential use in wearable electronics beyond the power generation realm. This electromechanical coupling, combined with their flexibility and thin film-like form, bestows dual-functional transducing capabilities to the device that are used in this research to demonstrate its use as a thin, wearable, and self-powered loudspeaker or microphone patch. To determine the device's performance and applicability, sound pressure level is characterized in both space and frequency domains for three different configurations. The confirmed device's high performance is further validated through its integration in three proposed systems: a music-playing flag, a sound recording film, and a flexible microphone for security applications.
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Title: Assessment of equation-of-motion coupled-cluster methods with approximate treatments of higher-order excitations and development of novel schemes for accurate calculations of diradical electronic spectra and bond breaking
Creator: Ajala, Adeayo Olayinka
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The development and implementation of electronic structure methods based on the exponential wave function ansatz of the single-reference coupled-cluster (CC) theory and its extensions to excited states exploiting the equation-of-motion (EOM) and linear responseframeworks have witnessed great success in a wide range of applications, but there are areas of chemistry, especially studies of chemical reaction pathways and photochemistry, where further improvements in the existing CC and EOMCC...
Show moreThe development and implementation of electronic structure methods based on the exponential wave function ansatz of the single-reference coupled-cluster (CC) theory and its extensions to excited states exploiting the equation-of-motion (EOM) and linear responseframeworks have witnessed great success in a wide range of applications, but there are areas of chemistry, especially studies of chemical reaction pathways and photochemistry, where further improvements in the existing CC and EOMCC methodologies are needed. In order to make progress in this area, it is important to evaluate the quality of the results that the existing CC/EOMCC methods provide, particularly in applications involving the interpretation and prediction of photochemical phenomena and electronic excitations spectra involving closed- and open-shell molecules. Thus, in the rst part of this PhD project we use a database set of 28 organic molecules ranging from linear polyenes, unsaturated cyclic hydrocarbons, aromatic hydrocarbons, and heterocycles to aldehydes, ketones, amides, and nucleobases to examine the performance of the completely renormalized (CR) EOMCC approaches forexcited electronic states, in which the relatively inexpensive non-iterative corrections due to triple excitations are added to the energies obtained with the standard EOMCC approach with singles and doubles, abbreviated as EOMCCSD. We focus on two variants of the approximately size-intensive CR-EOMCC methodology with singles, doubles, and noniterative triples, abbreviated as delta-CR-EOMCCSD(T), and the analogous two variants of the newer, rigorously size-intensive, left-eigenstate delta-CR-EOMCC(2,3) approach based on the biorthogonal formulation of the method of moments of CC equations.In the second part of this dissertation, we focus on the development of new EOMCC methods that are particularly well-suited for accurate calculations of diradical electronic spectra and single bond breaking. They are the cost-effective variants of the doubly electron-attached (DEA) EOMCC methodologies with up to 3-particle---hole (3p-1h) or 4-particle--2-hole (4p-2h) excitations, abbreviated as DEA-EOMCC(3p-1h)fNug and DEA-EOMCC(3p-1h,4p-2h){Nu}, respectively, which utilize the idea of applying a linear electron-attaching operator to the correlated CC ground state of an (N -2)-electron closed-shell reference system in order to generate the ground and excited states of the N-electron open-shell species of interest, while using Nu active unoccupied orbitals to select the dominant 3p-1h and 4p-2h terms. We demonstrate that the relatively inexpensive DEA-EOMCC(3p-1h,4p-2h){Nu} method signicantly reduces the computational costs of the parent active-space DEA-EOMCC(4p-2h){Nu} and full DEA-EOMCC(4p-2h) approaches, which are needed to obtain highly accurate results for open-shell systems having two electrons outside the closed-shell cores, such as diradicals, with virtually no loss in accuracy of the resulting excitation and dissociation energies. We also show that the active-space DEA-EOMCC(3p-1h){Nu} method accurately reproduces the results of the parent DEA-EOMCC(3p-1h) calculations at the small fraction of the cost. In addition to a series of benchmark examples that illustrate the performance of the DEA-EOMCC(3p-1h){Nu}, DEA-EOMCC(3p-1h,4p-2h){Nu}, and other DEA-EOMCC approaches with 3p-1h and 4p-2h excitations, including singlet{triplet gaps in methylene, trimethylenemethane, and several antiaromatic diradicals and bond breaking in the fluorine molecule, we provide the most essential details of DEA-EOMCC equations with an active-space treatment of 3p-1h and 4p-2h terms, as implemented in the compactcodes developed in this work and interfaced with the GAMESS package.
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Title: The systemic and regional hemodynamic changes responsible for 5-ht7 receptor mediated hypotension
Creator: Seitz, Bridget Mahon
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Serotonin (5-hydroxytrypamine; 5-HT) is known to cause complex dose-dependent effects within the cardiovascular system by altering vascular resistance and arterial pressure resulting in pressor or depressor outcomes. Increased circulating levels of 5-HT has been reported in chronic cardiovascular diseases. Therefore, it is important to understand the mechanisms by which 5-HT regulates cardiovascular system function under chronic conditions. Previous work in our laboratory found low doses of...
Show moreSerotonin (5-hydroxytrypamine; 5-HT) is known to cause complex dose-dependent effects within the cardiovascular system by altering vascular resistance and arterial pressure resulting in pressor or depressor outcomes. Increased circulating levels of 5-HT has been reported in chronic cardiovascular diseases. Therefore, it is important to understand the mechanisms by which 5-HT regulates cardiovascular system function under chronic conditions. Previous work in our laboratory found low doses of infused 5-HT causes a sustain fall in arterial pressure. The focus of my work was to understand the hemodynamic mechanisms that cause 5-HT-induced hypotension. A significant finding from my work was determining the activated 5-HT7 receptor is essential in mediating the chronic fall in arterial pressure with low doses of 5-HT. Rats lacking a functional 5-HT7 receptor (pharmacologically or genetically removed) resulted in no 5-HT-induced observed depressor response. At the systemic hemodynamic level, a decrease in total peripheral resistance (TPR) during 5-HT infusion was the result of an elevation in skeletal muscle blood flow mediated by the 5-HT7 receptor, which was measured with Doppler flow probes. Additionally, administration of 5-HT infusion relaxed splanchnic veins, via 5-HT7 receptor stimulation, when measured using novel imaging methodology. An increase in vascular capacitance from splanchnic venodilation is expected to affect arterial pressure by decreasing stroke volume (SV) and cardiac output. However, both SV and CO were elevated from the start and throughout the duration of 5-HT infusion, indicating that changes in vascular capacitance were unlikely to contribute to chronic 5-HT-hypotension. Previous evidence suggested chronic (but not acute) 5-HT-induced hypotension was dependent on activation of nitric oxide synthase. However, the magnitude of the pressor response to a nitric oxide synthase inhibitor was not significantly different between the control or 5-HT infused groups, concluding 5-HT-induced nitric oxide synthase may not be contributing. Collectively, my work provides insight into the unique cardiovascular pharmacology of the 5-HT7 receptor, a member of the 5-HT receptor family whose chronic cardiovascular effects have been little studied up to now. Future work should include: characterizing the impact of 5-HT7 receptor activation by endogenous 5-HT on chronic cardiovascular diseases such as hypertension and heart failure; and evaluating whether it is possible to capitalize on the unique cardiovascular effects of 5-HT7 receptor stimulation for therapeutic purposes.
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Title: Phase retrieval from continuous and discrete ptychographic measurements
Creator: Merhi, Sami Eid
Date: 2019
Collection: Electronic Theses & Dissertations
Description: In this dissertation, we present and study two novel approaches to phase retrieval -- an inverse problem in which one attempts to reconstruct a complex-valued function (or vector) from phaseless (or magnitude-only) measurements. Phase retrieval arises in several scientific areas including bio-chemistry, optics, astronomy, quantum mechanics, and speech signal processing. Early solutions to phase retrieval, although practical, lacked robustness guarantees. To this day, practitioners in...
Show moreIn this dissertation, we present and study two novel approaches to phase retrieval -- an inverse problem in which one attempts to reconstruct a complex-valued function (or vector) from phaseless (or magnitude-only) measurements. Phase retrieval arises in several scientific areas including bio-chemistry, optics, astronomy, quantum mechanics, and speech signal processing. Early solutions to phase retrieval, although practical, lacked robustness guarantees. To this day, practitioners in scientific imaging are still seeking demonstrably stable and robust recovery algorithms. Ptychography is a form of coherent diffractive imaging where diffraction patterns are processed by algorithms to recover an image of a specimen. More specifically, small regions of a specimen are illuminated one-at-a-time, and a detector captures the intensities of the resulting diffraction patterns. As such, the measurements are local and phaseless. In this work, we present two algorithms to recover signals from ptychographic measurements. The first algorithm aims to recover a discrete one-dimensional signal from discrete spectrogram measurements via a modified Wigner distribution deconvolution (WDD) method. While the method is known to practitioners of scientific imaging, robustness and recovery guarantees are lacking, if not absent; our contribution is to supply such guarantees. The second algorithm aims to approximately recover a compactly supported function from continuous spectrogram measurements via lifting and angular synchronization. This setup can be interpreted as the infinite-dimensional equivalent of discrete ptychographic imaging. Our contribution is a model which assumes infinite-dimensional signals and measurements ab initio, as opposed to most recent algorithms in which discrete models are a necessity. Finally, we consider the worst-case noise robustness of any phase retrieval algorithm which aims to reconstruct all nonvanishing vectors from the magnitudes of an arbitrary collection of local correlation measurements. The robustness results provided therein apply to a wide range of ptychographic imaging scenarios. In particular, our contribution is to show that stable recovery of high-resolution images of extremely large samples is likely to require a vast number of measurements, independent of the recovery algorithm employed. The first chapter introduces the phase retrieval problem and presents historical context, as well as applications in which phase retrieval manifests. In addition, we introduce ptychography, discuss existing WDD formulations, and compare these to our contribution in the discrete setting. Chapter 2 provides recovery guarantees for using aliased WDD methods to solve the phase retrieval problem in a discrete setting with sub-sampled measurements. In Chapter 3 we provide lower Lipschitz bounds for generic phase retrieval algorithms from locally supported measurements. Finally, Chapter 4 presents a numerical method to recover compactly supported functions from local measurements via lifting and angular synchronization.
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Title: Economic gain-aware routing protocols for device-to-device content dissemination
Creator: Hajiaghajani Memar, Faezeh
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The objective of this dissertation is to investigate Device-to-Device content dissemination protocols for maximizing the economic gain of dissemination for given combinations of commercial and network parameters. " -- Abstract.

Title: An ecological exploration of sport specialization pathways
Creator: DiSanti, Justin S.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Youth sport specialization has been a sustained area of interest in academic and practical settings. Though preliminary findings of the relationship between athletes' pathways of sport participation and their sport outcomes posit early specialization in a single sport as potentially harmful to an athlete's physical and psychological well-being, concern that athletes are specializing earlier, and to a greater degree, than ever before remains pervasive. In analyzing potential explanations for...
Show moreYouth sport specialization has been a sustained area of interest in academic and practical settings. Though preliminary findings of the relationship between athletes' pathways of sport participation and their sport outcomes posit early specialization in a single sport as potentially harmful to an athlete's physical and psychological well-being, concern that athletes are specializing earlier, and to a greater degree, than ever before remains pervasive. In analyzing potential explanations for this logical gap between recommendations and perceived behaviors, one notable gap of the literature is the lack of ecological, systems-based research that may better clarify what drives athletes to specialize in a single sport. In this study, a developmental, ecological, perception-based approach was used to explore youth athletes' pathways of sport participation (specifically, why they chose to specialize or play multiple sports) in relation to their ecological characteristics and subsequent sport experiences. To do so, a conceptual, ecological framework was developed to inform the design of this study, and the nature and strength of relationships between variables of this novel heuristic provided an initial understanding of the ecology of sport participation pathways. 132 current high school athletes participated in this study's testing battery, which surveyed elements of their sport participation, personal and contextual characteristics, their sport specialization behaviors and perceptions, and their expectations and subsequent experiences related to their chosen pathway. Results of this study highlighted several significant group differences and relationships between variables, and due to the exploratory nature of this study the non-significant findings also served as a hypothesis-generating mechanism for future research. Implications of these findings were explored in their relation to previous sport specialization literature and the study's guiding theoretical framework (i.e., the Developmental Model of Sport Participation and the Person-Process-Context-Time Ecological Model), and the results underscored the importance of accounting for the influence of context and competitive climate in understanding youth athletes' selected sport pathways and subsequent experiences.
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Title: Log-canonical poisson structures and non-commutative integrable systems
Creator: Ovenhouse, Nicholas
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Log-canonical Poisson structures are a particularly simple type of bracket which are given by quadratic expressions in local coordinates. They appear in many places, including the study of cluster algebras. A Poisson bracket is "compatible" with a cluster algebra structure if the bracket is log-canonical with respect to each cluster. In joint work with John Machacek, we prove a structural result about such Poisson structures, which justifies the use and significance of such brackets in...
Show moreLog-canonical Poisson structures are a particularly simple type of bracket which are given by quadratic expressions in local coordinates. They appear in many places, including the study of cluster algebras. A Poisson bracket is "compatible" with a cluster algebra structure if the bracket is log-canonical with respect to each cluster. In joint work with John Machacek, we prove a structural result about such Poisson structures, which justifies the use and significance of such brackets in cluster theory. The result says that no rational coordinate-changes can transform these brackets into a simpler form. The pentagram map is a discrete dynamical system on the space of plane polygons first intro- duced by Schwartz in 1992. It was proved to be Liouville integrable by Schwartz, Ovsienko, and Tabachnikov in 2010. Gekhtman, Shapiro, and Vainshtein studied Poisson geometry associated to certain networks embedded in a disc or annulus, and its relation to cluster algebras. These Poisson structures are log-canonical. Later, Gekhtman et al. and Tabachnikov reinterpreted the pentagram map in terms of these networks, and used the associated Poisson structures to give a new proof of integrability. In 2011, Mari Beffa and Felipe introduced a generalization of the pentagram map to certain Grassmannians, and proved it had a Lax representation. We reinterpret this Grassmann penta- gram map in terms of non-commutative algebra, in particular the double brackets of Van den Bergh, and generalize the approach of Gekhtman et al. to establish a non-commutative version of integrability. The integrability of the pentagram maps in both projective space and the Grass-mannian follow from this more general algebraic system by projecting to representation spaces.
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Title: "One leg in one, and one leg in the other" : reflections of vernacular musicians as music educators
Creator: Adams, Mark C.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: With a purpose of improving the experiences of vernacular musicians who want to become music educators so that more vernacular music-making can occur in K-12 music settings, this study explored the lived musical experiences of two vernacular musicians who successfully became music educators. The two grand tour problems of this study were:1. To describe how two vernacular musicians navigated their undergraduate music education programs.2. To describe if/how their vernacular musicianship...
Show moreWith a purpose of improving the experiences of vernacular musicians who want to become music educators so that more vernacular music-making can occur in K-12 music settings, this study explored the lived musical experiences of two vernacular musicians who successfully became music educators. The two grand tour problems of this study were:1. To describe how two vernacular musicians navigated their undergraduate music education programs.2. To describe if/how their vernacular musicianship contributed to their practice as music teachers. Ethnographic techniques were used within the framework of a multiple narrative case study to present the viewpoints of two participants, Carrie and Harrison (pseudonyms). Both were vernacular musicians prior to pursuing degrees in music education. The two participants’ stories revealed that they felt like they were living in two musical worlds. In their undergraduate experiences, participants felt their Western classical abilities were more highly valued than their vernacular musicianship skills, and they did not feel fully supported by faculty musically. In their teaching lives, their vernacular music-making backgrounds manifested through aural learning and rote teaching, creating, and their classroom environment. Participants experienced feelings of being an impostor during their undergraduate experiences, which, particularly for one participant, created fear and anxiety. These feelings of being an impostor continued into their teaching lives, typically brought about by preconceived program expectations (e.g., performance schedules, high-level student musical performance abilities) from community members and colleagues. These outside influences, at times, determined what vernacular music-making experiences they implemented into their classrooms and when it was “safe” to do so.Based on these data, I suggest institutions of higher education more equally value musics found outside Western classical cultures. This includes an evaluation of their audition processes, the support provided to “non-traditional” students, as well as a re-envisioning of required coursework, field experiences, and performance ensembles. Additionally, I suggest ways that teachers of K–12 musics can create a more diverse music education experience for students by including more vernacular music making. These suggestions include opportunities for informal learning, creative music making, and considerations for the classroom environment.
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Title: MEASURING AND MODELING THE EFFECTS OF SEA LEVEL RISE ON NEAR-COASTAL RIVERINE REGIONS : A GEOSPATIAL COMPARISON OF THE SHATT AL-ARAB RIVER IN SOUTHERN IRAQ WITH THE MISSISSIPPI RIVER DELTA IN SOUTHERN LOUISIANA, USA.
Creator: Kadhim, Ameen Awad
Date: 2018
Collection: Electronic Theses & Dissertations
Description: There is a growing debate among scientists on how sea level rise (SLR) will impact coastal environments, particularly in countries where economic activities are sustained along these coasts. An important factor in this debate is how best to characterize coastal environmental impacts over time. This study investigates the measurement and modeling of SLR and effects on near-coastal riverine regions. The study uses a variety of data sources, including satellite imagery from 1975 to 2017, digital...
Show moreThere is a growing debate among scientists on how sea level rise (SLR) will impact coastal environments, particularly in countries where economic activities are sustained along these coasts. An important factor in this debate is how best to characterize coastal environmental impacts over time. This study investigates the measurement and modeling of SLR and effects on near-coastal riverine regions. The study uses a variety of data sources, including satellite imagery from 1975 to 2017, digital elevation data and previous studies. This research is focusing on two of these important regions: southern Iraq along the Shatt Al-Arab River (SAR) and the southern United States in Louisiana along the Mississippi River Delta (MRD). These sites are important for both their extensive low-lying land and for their significant coastal economic activities. The dissertation consists of six chapters. Chapter one introduces the topic. Chapter two compares and contrasts bothregions and evaluates escalating SLR risk. Chapter three develops a coupled human and natural system (CHANS) perspective for SARR to reveal multiple sources of environmental degradation in this region. Alfa century ago SARR was an important and productive region in Iraq that produced fruits like dates, crops, vegetables, and fish. By 1975 the environment of this region began to deteriorate, and since then, it is well-documented that SARR has suffered under human and natural problems. In this chapter, I use the CHANS perspective to identify the problems, and which ones (human or natural systems) are especially responsible for environmental degradation in SARR. I use several measures of ecological, economic, and social systems to outline the problems identified through the CHANS framework. SARR has experienced extreme weather changes from 1975 to 2017 resulting in lower precipitation (-17mm) and humidity (-5.6%), higher temperatures (1.6 C), and sea level rise, which are affecting the salinity of groundwater and Shatt Al Arab river water. At the same time, human systems in SARR experienced many problems including eight years of war between Iraq and Iran, the first Gulf War, UN Security Council imposed sanctions against Iraq, and the second Gulf War. I modeled and analyzed the regions land cover between 1975 and 2017 to understand how the environment has been affected, and found that climate change is responsible for what happened in this region based on other factors. Chapter four constructs and applies an error propagation model to elevation data in the Mississippi River Delta region (MRDR). This modeling both reduces and accounts for the effects of digital elevation model (DEM) error on a bathtub inundation model used to predict the SLR risk in the region. Digital elevation data is essential to estimate coastal vulnerability to flooding due to sea level rise. Shuttle Radar Topography Mission (SRTM) 1 Arc-Second Global is considered the best free global digital elevation data available. However, inundation estimates from SRTM are subject to uncertainty due to inaccuracies in the elevation data. Small systematic errors in low, flat areas can generate large errors in inundation models, and SRTM is subject to positive bias in the presence of vegetation canopy, such as along channels and within marshes. In this study, I conduct an error assessment and develop statistical error modeling for SRTM to improve the quality of elevation data in these at-risk regions. Chapter five applies MRDR-based model from chapter four to enhance the SRTM 1 Arc-Second Global DEM data in SARR. As such, it is the first study to account for data uncertainty in the evaluation of SLR risk in this sensitive region. This study transfers an error propagation model from MRDR to the Shatt al-Arab river region to understand the impact of DEM error on an inundation model in this sensitive region. The error propagation model involves three stages. First, a multiple regression model, parameterized from MRDR, is used to generate an expected DEM error surface for SARR. This surface is subtracted from the SRTM DEM for SARR to adjust it. Second, residuals from this model are simulated for SARR: these are mean-zero and spatially autocorrelated with a Gaussian covariance model matching that observed in MRDR by convolution filtering of random noise. More than 50 realizations of error were simulated to make sure a stable result was realized. These realizations were subtracted from the adjusted SRTM to produce DEM realizations capturing potential variation. Third, the DEM realizations are each used in bathtub modeling to estimate flooding area in the region with 1 m of sea level rise. The distribution of flooding estimates shows the impact of DEM error on uncertainty in inundation likelihood, and on the magnitude of total flooding. Using the adjusted DEM realizations 47 ± 2 percent of the region is predicted to flood, while using the raw SRTM DEM only 28% of the region is predicted to flood.
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Title: Enteric glial cell regulation of oxidative stress and immune homeostasis during gastrointestinal inflammation
Creator: Brown, Isola Angella Maria
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Gastrointestinal (GI) motility dysfunction is a debilitating feature that presents asa symptom in a number of conditions. These include primary GI disorders likeinflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) but alsosecondary conditions like diabetes mellitus, Parkinson's Disease and simply as aconsequence of physiological aging. Although as many as 1 in 4 persons worldwide areaffected by GI motility dysfunction, there is a significant lack of safe and effective drugs,due...
Show moreGastrointestinal (GI) motility dysfunction is a debilitating feature that presents asa symptom in a number of conditions. These include primary GI disorders likeinflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) but alsosecondary conditions like diabetes mellitus, Parkinson's Disease and simply as aconsequence of physiological aging. Although as many as 1 in 4 persons worldwide areaffected by GI motility dysfunction, there is a significant lack of safe and effective drugs,due to a gap in the knowledge regarding the cellular mechanisms that contribute to GImotility dysfunction.Normal gut function is controlled by the enteric nervous system (ENS), anintrinsic neuronal network comprised of enteric neurons and supporting glial cells, whichis embedded within the walls of the GI tract. Death of enteric neurons, and the resultingdisruption of this neuronal network, contributes to motility dysfunction duringinflammation. In this dissertation, we investigate how increased oxidative stress andimbalanced immune homeostasis, key factors associated with GI inflammation,contribute to enteric neuropathy. We hypothesize a role for enteric glial cells, which arecapable of modulating ENS oxidative stress, and also have an importantimmunomodulatory role in the ENS.The work in this dissertation used a combination of transgenic animal strains,immunohistochemistry (IHC), pharmacological modulators, Ca2+ imaging and in situ andin vivo models of colitis to investigate our hypothesis. We show a key role for entericglial regulation of oxidative stress in mediating neuronal loss. During inflammation,purinergic activation of enteric glia drives enteric neuron death through a pathway thatrequires glial nitric oxide (NO) production and glial Cx43 hemichannels anddemonstrates a novel pathogenic role for enteric glia. Further, glial production of theantioxidant reduced glutathione (GSH) is necessary for neuronal survival in situ,although whole body GSH depletion has novel protective roles against key features ofmurine colitis. Mice with disrupted in T cell signaling of the anti-inflammatory cytokineTGFβ had altered GI function, immune homeostasis and glial activation at the level ofthe myenteric plexus. Lastly, we show that key pro-inflammatory mediators differentiallyalter glial Cx43 channel opening in quiescent versus activated enteric glia.Our data provide new evidence for an active role for enteric glial cells in GI(patho)physiology. Specifically, we demonstrate that enteric glia are involved inmediating the effects of oxidative stress and immune imbalance during GI inflammationand propose novel targets for the development of improved therapeutics to treat GImotility dysfunction.
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Title: The role of evidence in animal welfare science and standards : an ethical analysis
Creator: List, Monica
Date: 2019
Collection: Electronic Theses & Dissertations
Description: The development of the field of animal welfare science in recent decades, together with growth in public interest and ethical concerns for the welfare of animals has arguably led to an increase in regulation, both public and private, in the production and use of farmed animals. Animal welfare regulation, in the form of legislation, directives, industry guidelines and private standards is characterized by its reliance on scientific evidence to justify the conditions under which farmed animals...
Show moreThe development of the field of animal welfare science in recent decades, together with growth in public interest and ethical concerns for the welfare of animals has arguably led to an increase in regulation, both public and private, in the production and use of farmed animals. Animal welfare regulation, in the form of legislation, directives, industry guidelines and private standards is characterized by its reliance on scientific evidence to justify the conditions under which farmed animals should be bred, raised, transported, and slaughtered. One of the important roles scientific evidence plays in discussions around the regulation of farmed animal welfare is providing a seemingly ethically neutral understanding of how animals should be treated, in other words, it sidesteps ethical arguments for the treatment of animals, using science as a justification. However, per the dominant philosophy of science discourse on the role of values in science, no science can be considered value-free, and furthermore, there are acceptable roles for social and ethical values in scientific practice. These roles are not just acceptable, but necessary for the direction, interpretation, and application of science. This work argues that: a) given the broad range of ethical views regarding how we should treat animals, animal welfare science provides robust and credible guidance; b) furthermore, that animal welfare science is not only inspired or informed by animal ethics concepts and frameworks, but also has embedded social/ethical and cognitive values throughout; c) thus, in order to fulfil its purpose as a socially mandated science, animal welfare science should engage in intentional processes to determine adequate roles for various kinds of values underlying all stages of the scientific process and the interpretation and implementation of findings. This intentional examination of the role of values can be supported by more effective interdisciplinary collaboration. While animal welfare science is characterized in part by its interdisciplinary nature, it is important to question to what extent the research is truly interdisciplinary in the sense of fostering epistemic integration. Philosophical tools and analyses, beyond the typical uses of ethical frameworks as a starting point, can be valuable in facilitating effective interdisciplinary work, leading to a better understanding of the normative dimensions of animal welfare science.
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Title: Reinvestigating the beauty match up hypothesis and social comparison in food advertisements
Creator: Mundel, Juan
Date: 2018
Collection: Electronic Theses & Dissertations
Description: "The use of attractive models as a means to grab consumers' attention and influence their product evaluations and purchase intentions is a common occurrence among advertisers. Research shows that recurrent exposure to ads featuring models with idealized bodies can lead to negative self-evaluations, development of eating disorders, and depression, among other negative outcomes. Given their greater likelihood to express discontent with their bodies when compared to their male counterparts, most...
Show more"The use of attractive models as a means to grab consumers' attention and influence their product evaluations and purchase intentions is a common occurrence among advertisers. Research shows that recurrent exposure to ads featuring models with idealized bodies can lead to negative self-evaluations, development of eating disorders, and depression, among other negative outcomes. Given their greater likelihood to express discontent with their bodies when compared to their male counterparts, most of the literature on this issue has focused on women as the population under study. However, a third of all individuals suffering from eating disorders in the U.S. are males. This dissertation explores how males evaluate models featured in snack food advertisements when their bodies conform (or not) with advertising industry norms, and the effects of the pairing of different models with products perceived to be healthy (vs. unhealthy) on participants' evaluations of the self, the product, and the ad. Results showed a significant interaction between exposure to idealized bodies in advertisements and upward social comparison, indicating that respondents with higher social comparison scores had more negative evaluations of the ads. Exposure to ads with idealized bodies predicts participants' engagement in upward social comparison. Further, our results show that upward social comparison was a significant predictor of body dissatisfaction. Yet, overall participants had better evaluations of the ads when presented with unhealthy foods and models with idealized bodies, which stresses the need for guidelines for model casting in advertising."--Page ii.
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Title: Reducing levels of medical device contamination through package redesign, seal geometry and opening technique
Creator: Pérez, Paula
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Healthcare Acquired Infections (HAIs) are the cause of substantial pain and emotional stress. On any given day, 1 in every 25 patients in the US has an HAI. This has serious economic ramifications. Although the incidence of HAIs has been reduced through the implementation of varied prevention projects, work remains. Limited work has focused on indirect routes of contamination, and even fewer on packaging and handling as potential contributors. The presented work is among the first objectively...
Show moreHealthcare Acquired Infections (HAIs) are the cause of substantial pain and emotional stress. On any given day, 1 in every 25 patients in the US has an HAI. This has serious economic ramifications. Although the incidence of HAIs has been reduced through the implementation of varied prevention projects, work remains. Limited work has focused on indirect routes of contamination, and even fewer on packaging and handling as potential contributors. The presented work is among the first objectively investigating how package design and provider technique impact the sterile transfer of medical devices. Specific research goals were:1. To evaluate how package design features (inward curl, outward curl, tab design compared to a traditional, commercial pouch design) affect the likelihood of a device contacting non-sterile surfaces (the outside of the package or the hands of the provider).2. To characterize how aseptic technique (traditional vs. a modified approach) contributes to the likelihood of contact between medical devices and non-sterile surfaces during sterile transfer. 3. To develop a reliable, relatively easy and cost effective methodology that can be used to design and prototype new styles of flexible packages.4. To evaluate how peel geometry (using pouches created with the new prototyping method) impacts rates of contact between transferred devices and non-sterile surfaces.To explore goals 1, 2 and 4, a total of 136 healthcare providers were asked to present devices to a simulated sterile field. Participants’ gloved hands and the outside of test pouches were coated with a contamination simulant and participants were asked to present the contents of different pouch designs using two transfer techniques: “standard technique” where participants presented using their typical approach and a “modified technique” where participants were instructed to grab the package at the top center and transfer contents to the field using a single, fluid motion. Transferred devices were examined to verify the presence of the analyte and data was recorded in a binary fashion (yes/no) and analyzed using a generalized linear mixed model.Results indicated significant main effects of pouch design (p<0.001) and aseptic technique (P=0.0189) on rates of contact with non-sterile surfaces. Pouches designed to curl outward resulted in less contact than all other designs, this was true for both opening techniques: standard technique: (outward vs. commercial, inward and tab pouch) (14±2.5% vs. 26±3.5% (P <0.0047), 25±3.4% (P <0.0140) and 23±3.3% (P <0.0418), respectively) and modified technique (outward vs. commercial, inward and tab pouch) (8±1.8% vs. 22±3.2%, 25±3.5% and 25±3.5% respectively; all comparisons P = <0.0001) (goal 2). In support of goal 4, two geometries were created using a novel prototyping method we developed (goal 3-described within): one geometry represented a chevron pouch while the second was a rounded shape. Each of the two base geometries was modified with the addition of an extra seal intended to result in abrupt force differentials. A significant effect of geometry was indicated (P =0.0108). Specifically, the chevron geometry resulted in a higher rate of contact with non-sterile surfaces (42%±3%) than the round shaped geometry (35%±2%). Data did not support the idea that the addition of the bar intended to induce abrupt transitions in force profile had an effect on device contamination (P=0.1002).
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Title: Interpreting variation in restoration outcomes : functional traits shape community assembly and ecosystem functioning
Creator: Zirbel, Chad R.
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Making sense of the mechanisms by which communities assemble and provide ecosystem functions is central to ecological research. The recovery of diversity and ecosystem functioning are also primary objectives of ecological restoration, yet these outcomes are often unpredictable. Restoration ecology has typically focused on reinstating particular sets of species; however, this focus on taxonomic composition limits generalization between restorations. Traits, due to their mechanistic and...
Show moreMaking sense of the mechanisms by which communities assemble and provide ecosystem functions is central to ecological research. The recovery of diversity and ecosystem functioning are also primary objectives of ecological restoration, yet these outcomes are often unpredictable. Restoration ecology has typically focused on reinstating particular sets of species; however, this focus on taxonomic composition limits generalization between restorations. Traits, due to their mechanistic and generalizable nature, may provide insights into community assembly mechanisms that move beyond this idiosyncrasy. That is, a better understanding of how traits vary among species may predict how their dispersal, establishment, and persistence affect species’ distribution and abundance among sites that vary in abiotic and biotic conditions. Functional trait-based approaches may shed light on a second major goal of restoration: understanding the functioning of ecosystems and how this is related to the diversity and composition of communities. Thus, functional traits hold great promise for interpreting, predicting, and linking the assembly and functioning of communities. This promise remains poorly realized, however, as tests linking environmental conditions, functional traits, and ecosystem functioning in restoration are rare. In turn, restored systems offer a unique test of ecological theory at the scale of ecosystems. Here I use plant functional traits to study community assembly and ecosystem functioning in grasslands undergoing restoration. My first two chapters take a trait-based approach to studying processes such as invasion and species establishment that underlie community assembly using experimentally manipulated prairie restorations. I found that the extent to which a species’ traits are adapted to the local environment, but not how much their traits overlap with species already residing at a site, influence a species’ ability to invade a novel community. Likewise, trait-environment interactions play an important role in the invasion process, further supporting the idea that having traits that are adapted to a particular environment is important for invasion success. Furthermore, considering traits independent of their environmental context is inadequate for understanding community assembly processes and trait-environment interactions determine seedling establishment rates in recent prairie restorations. My last two chapters attempt to use functional traits to link community assembly and ecosystem functioning using a set of 29 restored prairies in southwestern Michigan. I found that environmental conditions predicted community weighted mean traits, showing the value of traits for studying community assembly. In addition, I found that both functional traits and environmental conditions play an important role in shaping ecosystem functioning during restoration, and the importance of both traits and environment on functioning depends on the function of interest. Because of this, variation in environmental conditions will be necessary to promote multiple ecosystem functions across restored landscapes through management, such as prescribed fire, and by installing restorations in at sites with different environmental conditions. These results highlight the utility of functional traits for connecting community assembly and ecosystem functioning during restoration. Within this same system I also asked how different aspects of diversity (taxonomic, functional, phylogenetic), beyond individual traits, influence ecosystem functioning and an ecosystem’s ability to produce multiple functions simultaneously (ecosystem multifunctionality). I found that phylogenetic diversity and the makeup of the landscape surrounding a restoration determine ecosystem multifunctionality, though the effect of landscape is much stronger than the effect of diversity. I also find no tradeoffs between ecosystem functions that contribute to multifunctionality across sites; instead, functions are independently affected by diversity, environmental, and landscape variables. In this case, the processes that increase many individual functions—increased phylogenetic diversity and more natural landscapes—will increase multifunctionality. All of this work demonstrates that trait-based approaches to restoration can help improve our understanding of community assembly and ecosystem functioning at the ecosystem scale, explain variation in restoration outcomes, and show how restored systems can offer a unique test of ecological theory at the scale of ecosystems.
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Title: I do not think it means what you think it means : problem definitions and collaborative relationships in coalitions
Creator: Lawlor, Jennifer
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Community psychologists frequently engage with coalitions in the study of community life. There is still little agreement on the way these organizations should be defined within the field and how they can support change. In my second chapter, I systematically review the literature within community psychology to define coalitions. I identify three types of coordination that they primarily engage in: knowledge coordination, negotiated coordination, and action coordination. Problem definition is...
Show moreCommunity psychologists frequently engage with coalitions in the study of community life. There is still little agreement on the way these organizations should be defined within the field and how they can support change. In my second chapter, I systematically review the literature within community psychology to define coalitions. I identify three types of coordination that they primarily engage in: knowledge coordination, negotiated coordination, and action coordination. Problem definition is one issue that arises in knowledge coordination among coalition members. Problem definitions can be understood as mental models and captured through using fuzzy cognitive maps. The way each individual defines the problem the group works on is often tied to collaborative behavior among coalition members. This brought me to two research questions: (1) In what ways are mental models similar or different within a coalition? (2) To what extent does mental model structure and content predict collaboration within a coalition? To address these questions, I interviewed members of a coalition to capture their mental models and surveyed them to capture their collaborative ties and demographics. To answer my first question, I assessed participants' mental models in terms of their content, structure, and function. Participants varied across each of these, but converged on a few key concepts. These findings suggest that mental modeling processes can identify differences among participants that might be used to support further dialogue among coalition members about the problem they work on. To answer my second research question, I employed an exponential random graph model using mental model similarity to predict collaborative network ties. Mental model similarity did not predict collaboration, but length of time participants have been in the coalition did emerge as a significant predictor of collaboration. These findings suggest a need for future research to assess predictors of collaboration in greater depth. I conclude with a summative discussion of the findings from each of my research questions, discussing implications for coalition practice, methods for studying them, and theories regarding coalitions.
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