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Title: Addressing the news media image in an age of skepticism
Creator: Shin, Soo Young
Date: 2018
Collection: Electronic Theses & Dissertations
Description: As the public’s skepticism toward news media has been growing, we need to better understand how the public perceives news media organizations. This study employed a useful conceptual lens from the marketing literature, image, to build a new conceptual framework within journalism, news media image to in aid in this understanding. Using focus group interviewing methods, the perceptions of 44 participants (across nine sessions) living in the Midwest in the U.S. were investigated to reveal the...
Show moreAs the public’s skepticism toward news media has been growing, we need to better understand how the public perceives news media organizations. This study employed a useful conceptual lens from the marketing literature, image, to build a new conceptual framework within journalism, news media image to in aid in this understanding. Using focus group interviewing methods, the perceptions of 44 participants (across nine sessions) living in the Midwest in the U.S. were investigated to reveal the news media image constructs perceived by the public. Through multidisciplinary literature review and group discussions, eight dimensions emerged: news quality, news usefulness, socially responsible, personality, usability, transparent, perspective-taking, and news selection bias. Results showed that participants believed that news media organizations are mostly unreliable and biased in selecting news worthy stories as the news organizations are under the pressure of making profit or political interests. However, the information provided by news organizations was regarded as being useful in getting relevant information to the participants’ lives and news organizations’ potential role of protecting democracy were valued by participants. Exploring how these dimensions represent people's image of the news media provides insight into the current American’s perceptions and biases toward the news media organizations.
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Title: Teacher’s Management of Classroom Interactions with English Language Learners : A Case Study of A Mainstream Teacher’s Practices and Beliefs
Creator: Teng, Yanjiang
Date: 2018
Collection: Electronic Theses & Dissertations
Description: In the past few decades, public schools in the United States have witnessed a fast-growing student population of English language learners (ELLs), who come from homes where a language other than English is dominant. The dual task of content and the English language learning has brought ELLs huge academic challenges, such as one-size-fit-all expectations, high-stakes tests, and unsatisfactory academic support, among many others. In addition, ELLs are often mainstreamed into content area...
Show moreIn the past few decades, public schools in the United States have witnessed a fast-growing student population of English language learners (ELLs), who come from homes where a language other than English is dominant. The dual task of content and the English language learning has brought ELLs huge academic challenges, such as one-size-fit-all expectations, high-stakes tests, and unsatisfactory academic support, among many others. In addition, ELLs are often mainstreamed into content area classes where teachers are underprepared to accommodate their learning needs. Thus, how mainstream teachers deal with ELLs for their content and English language learning merits further study. Educational scholars have paid increasing attention to the construct of teacher belief about teaching and learning. So far, studies on teachers’ beliefs suggest that the complex relationship between teacher beliefs and practice are not always static but rather emergent and likely to be moderated by contextual factors (e.g. Negueruela-Azarola, 2011). As Priestley, Biesta, and Robinson (2015) argued, examination of the issue should recognize the immediate situated context and focus on the beliefs-in-action to probe why the teacher makes decisions in that particular moment and for what purposes. Learning, from a sociocultural perspective, is achieved through the interactions between the teacher and students, as well as among the students themselves. In the classroom, teachers usually dominate the flow of the discourse and their beliefs on teaching and learning, to some extent, can shape the way of such teacher-student interaction and students’ learning. Classroom interaction is highly contextualized, spontaneous, and out of expectations. How the teacher manages this interactive practice and provides mediated support toward ELLs for both their content and language learning warrants further attention. This study draws upon a sociocultural perspective on learning, and a perspective that teachers’ decision-making is fluid, situated and context dependent. The present study examines how a mainstream teacher in a U.S. urban school manages her interaction with ELLs to scaffold their English and content learning and how these practices reflect her beliefs-in-action. This case study, using data generated from stimulated recall interviews, classroom videos, and observation notes, reports this teacher’s discursive practices with ELLs, along with her ongoing decision-making or her beliefs-in-action in this interactive process. The findings revealed that in this highly structured and teacher-dominated class, the interactive practice between the teacher and ELLs were limited. The teacher’s feedback on ELLs’ responses was not based on their learning needs but was impacted by some other contextual factors. The teacher’s strategies to scaffold ELLs’ learning were not as effective as she might expect: some are supportive of their learning, while others could impede their learning. Overall, the teacher’s challenges and dilemmas that arise from her interactive practice with ELLs were largely due to her lack of formal training in second language teaching. This study sheds light on the complexity of mainstream teachers’ beliefs and practices about ELLs. Furthermore, it advances our thinking on teachers’ practices and beliefs by bridging the link between teacher beliefs and classroom interaction in an interactive, moment-by-moment manner through the fine-grained analysis. In addition, it offers implications on better supporting and preparing mainstream teachers working with ELLs in a culturally and linguistically diverse environment.
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Title: Ecology and diversity of the lichen symbiosis : following established patterns, or an exception to the rule?
Creator: Scharnagl, Klara
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Few phenomena of biodiversity have perplexed researchers as much as the latitudinal diversity gradient. Though many taxa have been shown to follow this pattern of high species richness in the tropics and lower species richness towards the poles, no consensus has yet been reached regarding the drivers of this global pattern. Symbiosis, a long term and physically intimate interaction between two organisms, is a prevalent biotic interaction across the tree of life, yet few studies of the...
Show moreFew phenomena of biodiversity have perplexed researchers as much as the latitudinal diversity gradient. Though many taxa have been shown to follow this pattern of high species richness in the tropics and lower species richness towards the poles, no consensus has yet been reached regarding the drivers of this global pattern. Symbiosis, a long term and physically intimate interaction between two organisms, is a prevalent biotic interaction across the tree of life, yet few studies of the latitudinal diversity gradient have looked at symbiotic organisms. One example of symbiosis is the lichen symbiosis, an association between a filamentous fungal partner and a photosynthetic partner of green algae or cyanobacteria. Little is known about the latitudinal diversity gradient of lichens, yet their terrestrial ubiquity and symbiotic nature could provide insight into the drivers of this global pattern. To assess whether lichenized fungi follow a latitudinal diversity gradient, I compiled a dataset from three repositories for digitized herbarium specimen data: the Consortium for North American Lichen Herbaria, the Global Biodiversity Information Facility, and the Institutos Nacionais de Ciencia e Tecnologia. The fully compiled and quality-controlled dataset contained over 900,000 datapoints representing over 8,000 species. The raw species richness data revealed a peak in richness north of the equator outside of the tropics, however, this pattern mirrored the number of collections per latitudinal band. To correct for sampling effort biases in the digitized herbarium data, I rarefied species richness. I further corrected the rarefied species richness for land area, given the wide range of land area per latitudinal band in the Americas. This rarefied and land-area-corrected species richness data supports a latitudinal diversity gradient of lichenized fungi in the Americas. In a comparison to lichen checklist data at the country or state level, I revealed that tropical regions are underrepresented in the digitized herbarium data.To test the influence of sampling effort bias on the patterns revealed by the digitized herbarium data, I designed a field sampling approach directly targeted at the question of whether epiphytic lichens follow a latitudinal diversity gradient. This approach can help remove bias present in digitized herbarium data because they result from the compilation of many studies, each of which had its own taxonomic, regional, or ecological focus. To do so, I sampled from nine lowland forest sites across a 70-degree span of latitude in the Americas. At each site, I randomly chose ten plots, and sampled from ten trees within each plot for a total of nine hundred trees sampled. At each tree, I randomly chose a cardinal direction and placed a 20x40cm grid on the tree, collecting all lichens that fell within that grid. Thus, each site had the same amount of area surveyed for epiphytic lichen diversity. Lichens were identified to species in the lab. Data from systematic field sampling corroborate the latitudinal diversity gradient of (epiphytic) lichens. In a mixed effects model including tree and climate data, I found that this pattern is largely explained by host tree (substrate) diversity.With increasing land use change and impacts from climate change across the globe, it is increasingly important for us to set a baseline of patterns of diversity at large scales, as I did in my first two chapters, to then assess how these impacts are affecting the diversity of symbiotic organisms at different scales. For my third chapter, I applied my knowledge of lichen diversity to assess the impacts of three tropical forest restoration treatments on epiphytic lichens. The natural regeneration treatment had a small cohort of lichen species likely specialized to the high light and dry environment. The plantation and nucleation treatments had a mix of light and shade tolerant species and experienced higher competition from epiphytic bryophytes. The overall highest diversity of epiphytic lichens was found in the nucleation treatment, supporting this as the combination of the most cost-effective strategy that restores the greatest amount of tropical biodiversity.
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Title: Contemporary liberalism and the nation
Creator: Fram, Daniel
Date: 2019
Collection: Electronic Theses & Dissertations
Description: What is the status and legitimacy of the nation within the horizon of liberalism today? Surveying three representative, contrasting, recent works in contemporary political philosophy, I argue that the nation loses its status and legitimacy from every side. John Rawls's allegedly status-quo preserving theory in The Law of Peoples (Rawls 1999) defends only the shell of sovereignty and in fact points toward cosmopolitan aspirations. Cosmopolitan liberals, and conservative nationalists, therefore...
Show moreWhat is the status and legitimacy of the nation within the horizon of liberalism today? Surveying three representative, contrasting, recent works in contemporary political philosophy, I argue that the nation loses its status and legitimacy from every side. John Rawls's allegedly status-quo preserving theory in The Law of Peoples (Rawls 1999) defends only the shell of sovereignty and in fact points toward cosmopolitan aspirations. Cosmopolitan liberals, and conservative nationalists, therefore, claim with reason that liberalism is not capable of conferring status and legitimacy on the nation's "arbitrary" restrictions of individual autonomy (Nussbaum and Cohen 1996, MacIntyre 2003). But, in doing so, cosmopolitan liberalism creates a grave problem, for liberalism depends upon citizens to uphold freedom and upon limits to freedom to make freedoms meaningful. One would think to turn toward so-called liberal nationalist theories of liberalism, like David Miller's On Nationality (Miller 1995). But these, in turn, defend the nation only by depleting it of any content and rendering the very concept of the nation hollow. Neither of these two possible corrections of liberalism solves its problems with particularity and social unity; each only exacerbates them. My work as a whole therefore shows that contemporary liberalism tends to undermine the nation, on which it nevertheless relies. I demonstrate each part of the argument in separate chapters: two on Rawls's liberalism, one on Nussbaum's cosmopolitanism, and two on David Miller's liberal nationalism. These three perspectives represent a fairly complete spectrum of contemporary liberal thinking about the status of the nation.
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Title: Weighting in multilevel models
Creator: Tong, Bing
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Large-scale survey programs usually use complex sampling designs such as unequal probabilities of selection, stratifications, and/or clustering to collect data to save time and money. This leads to the necessity to incorporate sampling weights into multilevel models in order to obtain accurate estimates and valid inferences. However, the weighted multilevel estimators have been lately developed and minimal guidance is left on how to use sampling weights in multilevel models and which...
Show moreLarge-scale survey programs usually use complex sampling designs such as unequal probabilities of selection, stratifications, and/or clustering to collect data to save time and money. This leads to the necessity to incorporate sampling weights into multilevel models in order to obtain accurate estimates and valid inferences. However, the weighted multilevel estimators have been lately developed and minimal guidance is left on how to use sampling weights in multilevel models and which estimator is most appropriate.The goal of this study is to examine the performance of multilevel pseudo maximum likelihood (MPML) estimation methods using different scaling techniques under the informative and non-informative condition in the context of a two-stage sampling design with unequal probabilities of selection. Monte Carlo simulation methods are used to evaluate the impact of three factors, including informativeness of the sampling design, intraclass correlation coefficient (ICC), and estimation methods. Simulation results indicate that including sampling weights in the model still produce biased estimates for the school-level variance. In general, the weighted methods outperform the unweighted method in estimating intercept and student-level variance while the unweighted method outperforms the weighted methods for school-level variance estimation in the informative condition. In general, the cluster scaling estimation method is recommended in the informative sampling design. Under the non-informative condition, the unweighted method can be considered a better choice than the weighted methods for all the parameter estimates. Besides, the ICC has obvious effects on school-level variance estimates in the informative condition, but in the noninformative condition, it also affects intercept estimates. An empirical study is included to illustrate the model.
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Title: I. amhb : (anti)aromaticity-modulated hydrogen bonding. ii. evaluation of implicit solvation models for predicting hydrogen bond free energies
Creator: Kakeshpour, Tayeb
Date: 2019
Collection: Electronic Theses & Dissertations
Description: My doctoral research under Professor James E. Jackson focused on hydrogen bonding (H-bonding) using physical organic chemistry tools. In the first chapter, I present how I used quantum chemical simulations, synthetic organic chemistry, NMR spectroscopy, and X-ray crystallography to provide robust theoretical and experimental evidence for an interplay between (anti)aromaticity and H-bond strength of heterocycles, a concept that we dubbed (Anti)aromaticity-Modulated Hydrogen Bonding (AMHB). In...
Show moreMy doctoral research under Professor James E. Jackson focused on hydrogen bonding (H-bonding) using physical organic chemistry tools. In the first chapter, I present how I used quantum chemical simulations, synthetic organic chemistry, NMR spectroscopy, and X-ray crystallography to provide robust theoretical and experimental evidence for an interplay between (anti)aromaticity and H-bond strength of heterocycles, a concept that we dubbed (Anti)aromaticity-Modulated Hydrogen Bonding (AMHB). In the second chapter, I used accurately measured hydrogen bond energies for a range of substrates and solvents to evaluate the performance of implicit solvation models in combination with density functional methods for predicting solution phase hydrogen bond energies. This benchmark study provides useful guidelines for a priori modeling of hydrogen bonding-based designs.Coordinates of the optimized geometries and crystal structures are provided as supplementary materials.
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Title: Foundation and growth of the Cuban-based transatlantic slave trade, 1790-1820
Creator: Felipe Gonzalez, Jorge
Date: 2019
Collection: Electronic Theses & Dissertations
Description: This dissertation discusses the creation and expansion of the Cuban-based transatlantic slave trading infrastructure at the turn of the nineteenth century. Since the beginning of the conquest of the Americas, foreigners such as the Portuguese, Dutch, British, and Americans controlled the provision of captives to the Spanish colonies under a Spanish state-controlled system known as Asientos. Such dependency was challenged in the 1790s when a combination of international events, favorable...
Show moreThis dissertation discusses the creation and expansion of the Cuban-based transatlantic slave trading infrastructure at the turn of the nineteenth century. Since the beginning of the conquest of the Americas, foreigners such as the Portuguese, Dutch, British, and Americans controlled the provision of captives to the Spanish colonies under a Spanish state-controlled system known as Asientos. Such dependency was challenged in the 1790s when a combination of international events, favorable colonial legislation, and a restructuring of the colonial economy turned Cuba into an expanding sugar plantation economy based on African forced labor. By the 1820s, in just three decades, Cuban merchants had effectively overcome that external dependency by setting up the conditions for trading slaves on the African coast. This thesis argues that foreign slavers trading in the island since the 1790s were pivotal in training the first generation of Cuban slave ship captains, providing a slave merchant fleet to Cubans, and introducing Cuban merchants to African slave trading networks. In order to illustrate the establishment of Cuban operations in Africa, this dissertation focuses on the creation of a slave-trading corridor between Havana and Rio Pongo, Guinea-Conakry. Cuban merchants, I argue, reached the region known as Rio Pongo as a result of the U.S. slave traders who moved their operations to Cuba after 1808. The expansion of the slave trade in Rio Pongo to supply the expanding Cuban demand had also an impact on that coastal African society.
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Title: Multi-scale approaches to global challenges in a telecoupled world
Creator: Xu, Zhenci
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Global challenges such as water crisis, energy insecurity, biodiversity loss, land use change and climate change pose threats to the world's sustainability. Globalization enhances the connection of distant areas through various environmental and socioeconomic interactions. To solve the increasing challenges of achieving global sustainability in the context of globalization, the new telecoupling framework (socioeconomic and environmental interactions over distances) is proposed (Liu et al....
Show moreGlobal challenges such as water crisis, energy insecurity, biodiversity loss, land use change and climate change pose threats to the world's sustainability. Globalization enhances the connection of distant areas through various environmental and socioeconomic interactions. To solve the increasing challenges of achieving global sustainability in the context of globalization, the new telecoupling framework (socioeconomic and environmental interactions over distances) is proposed (Liu et al. 2013). A growing body of research has been exploring the dynamics, impacts, mechanisms, and structure of distant interactions involving global challenges. However, based on the telecoupling framework, we find no research that studies the evolution of multiple global environmental and socioeconomic interaction networks together. Also, the interactions between two kinds of distant virtual resource transfers simultaneously and the drivers of virtual resource transfers at the national scale are still unknown. Little research explores the evolution of virtual resource transfers at a national scale. The impacts of distant interactions on sending systems' sustainability at the regional scale has rarely been quantified and systematically analyzed. To address these knowledge gaps, I did the following work: First, I assessed the evolution of global telecouplings such as water, energy, land, CO2 emission, nitrogen emission and financial capital transfer networks and discussed how they have impacts on global water scarcity, energy crisis, land use change, global warming and nitrogen pollution. Second, I evaluated the interactions across two kinds of national telecouplings (interregional water and energy networks), and discussed their implications for the trading region's water scarcity and energy security, and explore the drivers of national telecouplings. Third, I studied the evolution of national virtual energy network. Fourth, I explored the water and food sustainability in a sending system of telecoupling (food transfer aimed at ensuring food security in the receiving system) at the regional scale. These four works have been accomplished in four chapters, respectively.Main findings from this dissertation include: At the global scale, the volumes of all these flows, except for land flow, increased over time. Financial capital flows increased most (188.9%), followed by flows of CO2 (59.3%), energy (58.1%), water (50.7%) and nitrogen (10.5%), while land transfer decreased by 8.8%. At the national scale using China as a demonstration, 40% of provinces gained one kind of resource (either water or energy) through trade at the expense of losing the other kind of internal resource (energy or water), and 20% of provinces suffered a double loss of both water and energy. The remaining provinces gained both water and energy. Over time, the total virtual energy transferred from energy-scarce to energy-abundant provinces increased from 43.2% to 47.5% from 2007 to 2012. At a regional scale, irrigated agriculture's annual water footprint in the North China Plain increased from 53 billion m3 in 1986 to 78 billion m3 in 2010. All counties faced unsustainable water use - local water consumption was greater than local renewable freshwater - even as the average crop water productivity increased from 0.90 kg.m-3 to 1.94 kg.m-3. These findings provide useful information for policy making to address environmental and socioeconomic challenges and build distant cooperation across multiple scales.
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Title: A climatology of persistent high relative humidity for the lower peninsula of Michigan : implications for health and agriculture
Creator: Komoto, Kara
Date: 2019
Collection: Electronic Theses & Dissertations
Description: High values of relative humidity have implications for many processes including human health, animal health and production, and crop disease. Despite its importance, little research has been completed about the persistence of high relative humidity. The goals of this study were to 1) create a baseline climatology of the persistence of high relative humidity (HRH), defined as ≥ 60%, and extremely high relative humidity (EHRH), defined as ≥ 85%, for the Lower Peninsula of Michigan and 2)...
Show moreHigh values of relative humidity have implications for many processes including human health, animal health and production, and crop disease. Despite its importance, little research has been completed about the persistence of high relative humidity. The goals of this study were to 1) create a baseline climatology of the persistence of high relative humidity (HRH), defined as ≥ 60%, and extremely high relative humidity (EHRH), defined as ≥ 85%, for the Lower Peninsula of Michigan and 2) examine, using persistent EHRH events as a surrogate for leaf wetness duration, the frequency of favorable environmental conditions for apple scab and cherry leaf spot, major crop diseases in the state. Results demonstrate that although overall persistent relative humidity events often occur throughout the state, their frequency appears to be decreasing with time. Temporal trends in the frequency of favorable environmental conditions for apple scab and cherry leaf spot vary by location and disease, but there is a general trend toward fewer occurrence of favorable environmental conditions. The climatological analyses provide Michigan stakeholders with essential information for long-term planning and management to mitigate and/or adapt to persistent high relative humidity and to assess future changes in persistent high relative humidity as expected with climate change.
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Title: Connecting reflection and practice : transforming a mathematics classroom culture of participation
Creator: Martinez Hinestroza, Jose Manuel
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Unlike previous research on participation in mathematics classrooms that focuses on the teacher's role eliciting student talk, the purpose of this dissertation is to study the interactive process through which a teacher connected her reflection and practice, fostering transformations in the culture of participation in a third-grade Spanish immersion mathematics classroom. I draw on hermeneutic listening (Davis, 1996) to understand the teacher's departure from listening for predetermined ways...
Show moreUnlike previous research on participation in mathematics classrooms that focuses on the teacher's role eliciting student talk, the purpose of this dissertation is to study the interactive process through which a teacher connected her reflection and practice, fostering transformations in the culture of participation in a third-grade Spanish immersion mathematics classroom. I draw on hermeneutic listening (Davis, 1996) to understand the teacher's departure from listening for predetermined ways of participating. Methods from participatory design research with children (Bang & Vossoughi, 2016; Groundwater-Smith et al., 2014) and analytical tools from social semiotics (van Leeuwen, 2005) informed the collaborative design and analysis of interventions intended to promote a more inclusive culture of participation. Findings indicate that bringing the students' and the teachers' perspectives on participation into dialogue helped the teacher broaden her ideas on participation. A prolonged, iterative process was necessary to connect these reflections to a practice where the teacher learned to listen hermeneutically for participation. This process started with teacher-researcher co-designed interventions and continued as the teacher recognized participation in unexpected places and moments. The culture of participation evolved toward embracing multiple ways of participating in cooperative mathematical activity in which the students and the teacher addressed unanticipated ideas that emerged in interactions. I describe the semiotic innovations that characterized these transformations and the contextual influences that mediated semiotic innovation. I discuss implications for mathematics educatioSn research and teacher professional development.
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Title: Determinants of eating behaviors of us army ROTC cadets in Midwestern universities
Creator: George, Beatriz G.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Young adults 18-25 years of age, the largest demographic of the military, experience a high burden of obesity and eating disorders (ED) despite an emphasis on physical fitness, body composition, and operational readiness. Etiologic models for obesity and ED suggest body dissatisfaction (BD), dieting, negative affect (NA), and affect regulation represent potentially shared pathways. However, no studies have examined these factors and their shared pathways in military personnel, including ROTC...
Show moreYoung adults 18-25 years of age, the largest demographic of the military, experience a high burden of obesity and eating disorders (ED) despite an emphasis on physical fitness, body composition, and operational readiness. Etiologic models for obesity and ED suggest body dissatisfaction (BD), dieting, negative affect (NA), and affect regulation represent potentially shared pathways. However, no studies have examined these factors and their shared pathways in military personnel, including ROTC cadets. The overarching aim of this dissertation research was to investigate if ED symptoms were associated with body mass index (BMI), an indicator of obesity, and to describe potential correlates of their development. Three specific aims of this research focus on: 1) the prevalence and correlates of ED risk classification and symptoms in ROTC cadets, 2) the association between ED symptoms and BMI, and their potentially shared mechanisms, psychological inflexibility related to BD and dieting, and 3) the gaps in knowledge about eating behaviors and mediators of eating behaviors within the ROTC context and from perspective of ROTC cadets.In 2018, US Army ROTC cadets (n = 205) were recruited from two Midwestern universities and completed questionnaires about demographics, military-specific eating behaviors and mediators of eating behaviors, ED symptoms, and anthropometric measures. Chi-square, multivariable logistic regression, and multiple linear regression were performed in determining the rate of ED risk classification and correlates of ED risk classification and symptoms (Aim 1). Two measures of psychological inflexibility related to BD and dieting, in addition to the data for Aim 1, were used in mediation path analysis to examine the association of ED symptoms to BMI, and the indirect effects as mediated by psychological inflexibility related to BD and dieting (Aim 2). A purposively selected sample of eighteen cadets participated in one-on-one, semi-structured telephone interviews on eating behaviors and their mediators in the context of ROTC (Aim 3). Interviews were analyzed using thematic analysis to identify the most important themes and determinants related to eating behaviors in ROTC cadets.We found that ED symptoms and ED risk classification are prevalent in a sample of US Army ROTC cadets (10.1% of sample). Correlates associated with greater likelihood of ED risk classification and elevated ED symptoms were: sex, dieting, and military contextual factors such as attempting dieting and weight loss to meet body composition standards, and peers' comments on weight. Total ED symptoms scores were positively associated with BMI and partially mediated by psychological inflexibility related to BD and dieting. Cadets discussed perceived determinants of eating behaviors which included traditional determinants (e.g. time, money, nutrition knowledge) and ROTC-context specific determinants (e.g. preparation for body composition assessments and body image perceptions), which contributed to unhealthy weight control behaviors (dieting) and negative body image perceptions (BD) for some cadets. In conclusion, the prevalent correlates for eating disorder symptoms and risk in the sample of US Army ROTC cadets in this study were factors related to the enforcement of body composition standards and body image perceptions in the military context which may contribute to the development of dieting, BD, and NA. Longitudinal and/or intervention studies on this important topic may benefit our understanding of how ED symptoms and obesity develop over time and how targeting dieting, BD, NA, and affect regulation may be leveraged to mitigate ED and obesity to promote physical fitness, operational readiness and health in military personnel.
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Title: Optogenetic analysis of excitatory and inhibitory neurotransmission in the enteric nervous system
Creator: Perez-Medina, Alberto L.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: The enteric nervous system (ENS) is embedded within the gastrointestinal (GI) tract and controls GI function. Impaired ENS function leads to altered patterns of motility and secretion, causing GI disease. For instance, functional gastrointestinal disorders (FGID) are caused by poorly understood alterations in the structure and function of nerves, smooth muscle cells (SMC), and other cell types in the GI tract. It is estimated that these disorders comprise about 41% of the total GI...
Show moreThe enteric nervous system (ENS) is embedded within the gastrointestinal (GI) tract and controls GI function. Impaired ENS function leads to altered patterns of motility and secretion, causing GI disease. For instance, functional gastrointestinal disorders (FGID) are caused by poorly understood alterations in the structure and function of nerves, smooth muscle cells (SMC), and other cell types in the GI tract. It is estimated that these disorders comprise about 41% of the total GI complications in the United States. Also, altered patterns of motility that occur in the GI muscles is a hallmark characteristic of FGIDs. Although the ENS is fairly understood, further elucidation of the enteric circuitry that governs GI motility would help to understand the pathophysiology of FGID. For that reason, identifying the contributions of classes of enteric neurons that control GI motility and secretion could aid in the identification of novel therapeutic targets for the treatment of FGIDs. A widely used method to study neural control of GI motility is sharp-electrode electrophysiological recordings from the smooth muscle or enteric neurons. Conventional, intracellular electrophysiological recordings have relied on electrical stimulation of enteric neurons which will activate all neurons in an ex vivo preparation of the ENS, and does not allow cell-specific activation of individual subpopulations of myenteric neurons. To overcome this problem, we used immunohistochemical methods to identify subpopulations of myenteric neurons and the optogenetically activated protein channelrhodopsin-2 (ChR2) that can be selectively expressed in subsets of enteric neurons. In Chapter 3, immunohistochemical studies of the mouse enteric nervous system are performed using the purinergic neuronal marker, vesicular nucleotide transporter (VNUT) along with markers for specific subsets of myenteric neurons and nerve fibers (e.g., neuronal nitric oxide synthase, choline acetyltransferase, calretinin, calbindin, and tyrosine hydroxylase),. Chapter 4 compares electrical and optogenetic electrophysiology recordings from myenteric neurons of mice that express ChR2 in nNOS neurons. The studies described in Chapter 5 use ChAT-ChR2-YFP-BAC transgenic mice which have eYFP tagged ChR2 expressed in cholinergic neurons. Optogenetics was used to isolate the cholinergic component of the ENS. The findings discussed in this dissertation provides evidence of a more sophisticated enteric circuitry of GI motility. (1) Purinergic neurons are likely a separate subpopulation of enteric neurons. VNUT is only expressed in the form of punctate varicosities at the nerve fibers and is not endogenously expressed in the soma of enteric neurons. VNUT also does not appear to colocalize with other neuronal immunoreactive markers within the myenteric plexus (mp), the tertiary plexus (tp), or circular smooth muscle layer of all tested tissue preps. (2) BLS of ChR2 expressed in nNOS neurons induced a purinergic/nitrergic biphasic IJP, suggesting that nNOS IMNs co-releases a purine as a neurotransmitter. Ectopic expression of ChR2 in non-nNOS neurons, however, could explain the biphasic IJP responses during electrophysiology recordings. Hence, the existence of separate subset populations of IMN populations (e.g., nNOS only and purinergic only IMNs) can't be ruled out. (3) BLS of ChR2 expressed in ChAT positive neurons induced EJPs and IJP responses. Inhibition of the nicotinic ACh receptor (nAChR) with mecamylamine significantly reduced the light-evoked IJP. Bath application of the purinergic P2Y1 antagonist, MRS 2179, was sufficient to abolish the IJP response, while the muscarinic ACh receptor antagonist, Scopolamine, abolished the EJP response. The data suggest that BLS of ChR2 activates cholinergic EMNs and cholinergic interneurons, and that activation of the cholinergic interneurons activates purinergic only IMNs that supply the smooth muscle, resulting in a predominant purinergic only IJP. Taken together, this work provides evidence for a diverse and more complex enteric neural circuit of GI motility. Future experiments should, however, focus on studying these enteric circuits at the level of the neuron, as these studies can provide a more in-depth analysis of the enteric circuitry.
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Title: Solidarity, safety, and online sovereignty : an inquiry into the social media sharing practices of indigenous and chicana women
Creator: Hutchinson, Leslie A.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: This dissertation contains a cultural, digital rhetorics inquiry into the social media sharing practices of Indigenous and Chicana women. Working alongside three women from her local community, I investigated how these women navigate concerns about online safety, intellectual property, and surveillance. To conduct my study, I integrated cultural rhetorics research methods into my research design, which informed how I collected data through hosting a talking circle and conducting follow-up...
Show moreThis dissertation contains a cultural, digital rhetorics inquiry into the social media sharing practices of Indigenous and Chicana women. Working alongside three women from her local community, I investigated how these women navigate concerns about online safety, intellectual property, and surveillance. To conduct my study, I integrated cultural rhetorics research methods into my research design, which informed how I collected data through hosting a talking circle and conducting follow-up interviews. Then, using grounded theory to analyze my data, I found that: 1) though these women experience various social oppressions within social media spaces, they find and create community to collectively act in resistance; and 2) the acts of resistance in which these women engage expand scholarly understandings of how social media platforms are designed to asymmetrically oppress users from marginalized backgrounds. Together, these findings dispel the myth that women-and particularly women of color-have had no stake in the development of online platforms. I argue, rather, that despite how these platforms are designed, women of color critically enact cultural sovereignty in online spaces through asserting their identities, fighting for political rights, and creating community in acts of not only resistance, but survivance.
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Title: Integrated remote sensing and crop system modeling for precision agriculture across spatial and temporal scales
Creator: Peter, Bradley George
Date: 2019
Collection: Electronic Theses & Dissertations
Description: In light of global environmental change, population pressure, and food production demands, there is considerable value in mapping biogeographic crop niche and characterizing crop productivity at multiple scales to enhance the impact of agricultural improvement across Africa. Crop system research has advanced sustainable strategies for intensifying food production; however, questions regarding where to implement innovative technologies are largely unresolved.This dissertation focuses on four...
Show moreIn light of global environmental change, population pressure, and food production demands, there is considerable value in mapping biogeographic crop niche and characterizing crop productivity at multiple scales to enhance the impact of agricultural improvement across Africa. Crop system research has advanced sustainable strategies for intensifying food production; however, questions regarding where to implement innovative technologies are largely unresolved.This dissertation focuses on four geographic questions: (1) Where is the fundamental climate niche of maize, pigeonpea, and sorghum across Africa? (2) Where are marginal lands in Malawi and what are the underlying drivers of marginality? (3) Based on the drivers of marginal maize production, what are geographic scaling options for integration of pigeonpea into maize-based cropping systems? (4) What spatial resolutions are effective for conducting precision agriculture at the farm scale in smallholder systems? Overarching themes within the geographic discipline such as the modifiable areal unit problem and ecological fallacy problem underpin this research. Marginal areas for maize are highlighted at the Africa and Malawi scales and overlain with the optimal climate niche for crops such as sorghum and pigeonpea that offer multiple ecosystem services (e.g., soil rehabilitation through nitrogen fixation). Crop productivity is evaluated at scales relative to policy making delineations in Malawi (i.e., country, district, and extension planning area) to disentangle heterogeneity at local scales that may appear homogeneous at broader scales. At the Malawi farm scale, this research included the use of a small unmanned aerial system (sUAS), national government satellites (e.g., Sentinel-2), and commercial satellites (e.g., SPOT 6). Spectral measurements of crop status were evaluated at multiple spatial resolutions (ranging from 0.07-20-m) to determine what spatial resolutions and what spectral indices are most effective for estimating crop yields and crop chlorophyll.Results of this research include high spatial resolution maps of maize, pigeonpea, and sorghum suitability across Africa, indicating that pigeonpea and sorghum occupy unique agroecological zones throughout the continent (e.g., sorghum in the Sahel region). Similarly, pigeonpea suitability in Malawi occupies a greater land area than the extent to which it is currently cultivated, demonstrating that integration into maize-based cropping systems, particularly where soil is marginal, can have beneficial scaling outcomes. For the smallholder farm scale, problems of clouds and satellite revisit rates have not yet been overcome for precision agriculture. In this regard, sUAS are a promising option for relating spectral signals to on-farm measurements of crop status. Evidence from drone flights conducted at two experimental farms in the central region of Malawi (Nyambi and Ntubwi) suggest that spatial resolutions closer to the plant scale (i.e., 14-27-cm) are most effective for relating spectral imagery to crop status. Moreover, the green normalized difference vegetation index (GNDVI) and green soil adjusted vegetation index (GSAVI) were consistently correlated with crop chlorophyll and yield, illustrating that a broad range of indices should be evaluated for precision agriculture.
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Title: The interaction between feature- and space-based attention
Creator: Ozsarfati, Gozde
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Although the separate effects of feature- and space-based attention are relatively well established, the conjoint effects of attending to both a location and a feature are under-investigated. I analyzed the literature and extracted three approaches that explain such conjoint effects, namely the independence, sensory gating, and boosting approaches. The three approaches have substantial supports and shortcomings, and the current study will investigate which of the three approaches provide the...
Show moreAlthough the separate effects of feature- and space-based attention are relatively well established, the conjoint effects of attending to both a location and a feature are under-investigated. I analyzed the literature and extracted three approaches that explain such conjoint effects, namely the independence, sensory gating, and boosting approaches. The three approaches have substantial supports and shortcomings, and the current study will investigate which of the three approaches provide the best prediction of behavioral performance. I conducted two experiments to investigate whether the interplay between feature- and space-based attention varied as a function of the elapsed time between the cue and the target onset. A space-feature combination cue directed attention to a target on which participants discriminated small changes in color saturation. Both the spatial and feature cues were partially valid, making it possible to assess the cueing effect. The time difference between the cue and the saturation change onsets was manipulated in fine steps. Experiment 1 showed that space- and feature-based attention had an interactive effect on performance, such that feature-based attention did not influence performance outside the focus of space-based attention regardless of the temporal asynchrony between the cue and target onset. Experiment 2 was conducted to determine which of the three approaches provided the best account for the interaction pattern by adding a spatially neutral condition. It showed that feature- and space-based attention influenced performance, yet feature-based attention could not influence the performance outside the focus of spatial attention regardless of the temporal asynchrony between the cue and target onset. Moreover, the effectiveness of feature-based attention was equivalent at the spatially valid and neutral locations. In conclusion, the findings resemble with the predictions of the sensory gating approach. While feature-based attention could operate at the attended location or under diffused spatial attention equally well, its effectiveness diminished outside the focus of spatial attention. Moreover, the spatial filter imposed on feature-based attention is more permeable than originally proposed by the sensory gating approach. Lastly, feature-based attention does not fully spread to an unattended location regardless of the time difference between the cue and target onsets.
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Title: DOWNLINK RESOURCE BLOCKS POSITIONING AND SCHEDULING IN LTE SYSTEMS EMPLOYING ADAPTIVE FRAMEWORKS
Creator: Abusaid, Osama M.
Date: 2018
Collection: Electronic Theses & Dissertations
Description: The present expansions in size and complexity of LTE networks is hindering their performance and their reliability. This hindrance is manifested in deteriorating performance in the User Equipment’s throughput and latency as a consequence to deteriorating the E-node B downlink throughput. This is leading to the need of smart E Node Base with various capabilities adapting to the changing communication environment. The proposed work aims at developing Self Organization (SO) techniques and...
Show moreThe present expansions in size and complexity of LTE networks is hindering their performance and their reliability. This hindrance is manifested in deteriorating performance in the User Equipment’s throughput and latency as a consequence to deteriorating the E-node B downlink throughput. This is leading to the need of smart E Node Base with various capabilities adapting to the changing communication environment. The proposed work aims at developing Self Organization (SO) techniques and frameworks for LTE networks at the Resource Blocks (RB) scheduling management level. After reviewing the existing literature on Self Organization techniques and scheduling strategies that have been recently implemented in other wireless networks, we identify several contrasting needs that can jointly be addressed. The deployment of the introduced algorithms in the communication network is expected to lead to improved and upgraded overall network performance. The main feature of the LTE networks family is the feed-back that the cell receives from the users. The feedback includes the down link channel assessment based on the User Equipment (UE) measure Channel Quality Indicator (CQI) in the last Transmission Time Interval (TTI). This feed-back should be the main decision factor in allocating Resource Blocks (RBs) among users. The challenge is how could one maps the users’ data onto the RBs based on the CQI. The Thesis advances two approaches towards that end:- the allocation among the current users for the next TTI should be mapped, consistent with historical feed-back CQI received from users over prior transmission durations. This approach also aims at offering a solution to the bottle-neck capacity issue in the scheduling of LTE networks. To that end, we present an implementation of a modified Self Organizing Map (SOM) algorithm for mapping incoming data into RBs. Such an implementation can handle the collective cell enabling our cell to become smarter. The criteria in measuring the E-node Base performance include throughput, fairness and the trade-off between these attributes.- Another promising and complementary approach is to tailor Recurrent Neural Networks (RNNs) to implement optimal dynamic mappings of the Resource Blocks (RBs) in response to the history sequence of the Channel Quality Indicator CQI feedback. RNNs can successfully build its own internal state over the entire training CQI sequence and consequently make the prediction more viable. With this dynamic mapping technique, the prediction will be more accurate to changing time-varying channel environments. Overall, the collective cell management would become more intelligent and would be adaptable to changing environments. Consequently, a significant performance improvement can be achieved at lower cost. Moreover, a general tunability of the scheduling system becomes possible which would incorporate a trade-off between system complexity and QoS.
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Title: The distribution and dynamics of resistance genes in soil microbiomes
Creator: Dunivin, Taylor Katherine
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "The soil microbiome harbors immense microbial biodiversity that encodes important functions of interest to public health. These include functional genes that encode resistance to antibiotics and arsenic. In the case of antibiotic resistance, transfer from environmental strains to pathogens is a public health risk, and arsenic resistance and metabolisms are important for bioremediation as they impact the fate of arsenic in the environment. While these resistance genes are well-characterized...
Show more"The soil microbiome harbors immense microbial biodiversity that encodes important functions of interest to public health. These include functional genes that encode resistance to antibiotics and arsenic. In the case of antibiotic resistance, transfer from environmental strains to pathogens is a public health risk, and arsenic resistance and metabolisms are important for bioremediation as they impact the fate of arsenic in the environment. While these resistance genes are well-characterized in vitro, the full scope of their environmental distribution, diversity, and interspecies transfer is unknown. A better understanding of the diversity and distribution of resistance genes would provide insights into the potential for mitigation of public health problems such as arsenic contamination and antibiotic resistance. The work in this dissertation used a combination of cultivation-dependent and -independent techniques to better understand the dynamics and distributions of antibiotic and arsenic resistance genes in the environment. The influence of a disturbance on microbial antibiotic resistance and arsenic related genes was investigated by examining soils overlaying an underground coal mine fire in Centralia, PA. Additionally, soil meta-analyses were used to determine broader distributions patterns of these genes. These data and methods not only provide insights into the distributions and dynamics of antibiotic resistance and arsenic related genes in soil microbiomes but also provide a framework for future studies of other functional genes."--Page ii.
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Title: The cultivation of haitian women's sense of selves : towards a field of action
Creator: Leger, Shewonda
Date: 2019
Collection: Electronic Theses & Dissertations
Description: This multimodal dissertation makes space for diasporic Haitian women's stories and lived experiences which continue to be under-theorized within rhetorical scholarship but are clearly significant within Haitian communities and rhetorical traditions. To bring awareness to Haitian women's lived experiences, in my dissertation, I present the findings of a study that addresses the ways diasporic Haitian women revisit and navigate memories through reflection to make sense of the ways their lived...
Show moreThis multimodal dissertation makes space for diasporic Haitian women's stories and lived experiences which continue to be under-theorized within rhetorical scholarship but are clearly significant within Haitian communities and rhetorical traditions. To bring awareness to Haitian women's lived experiences, in my dissertation, I present the findings of a study that addresses the ways diasporic Haitian women revisit and navigate memories through reflection to make sense of the ways their lived experiences contribute to different aspects of their identities. The two situations I used as catalysts for memory were---inhabiting and reflecting on practices and conversations of the Haitian kitchen space---and, looking at and revisiting photographs to understand how we, claim, (re)claim, and/or discover identities. To make this inquiry, I explored the act of reflection through in-depth interviews with three diasporic Haitian women. I aim to understand what new knowledge(s) do diasporic Haitian women recognize about their identities through the act of reflection and navigating memories? Further, I work towards understanding how do these new knowledges modify identity performances in the "now"? And, how does a sense of identity consciousness contribute to diasporic Haitian womens' experiences and practices moving forward? Overall, using modes, such as documentary and photography in my dissertation, I make space for diasporic Haitian women's voices in rhetoric and composition to disrupt colonial images, visions, myths, stereotypes, and/or fantasies, replacing them with the complexity of our cultural identities from our own lens.
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Title: Allied studies on total sythesis of cyclic tripeptide TMC-95 via an iridium catalyzed borylation/deborylation strategy and teaching organic chemistry in "words"
Creator: Shen, Fangyi
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Arylboronate esters are versatile synthetic building blocks. Iridium catalyzed C-H activation/borylation reactions are a green way of making such building blocks as these reactions often obviate the need for prior functionalization (e.g. halogenation), the use of pyrophoric reagents, cryogenic conditions, etc. Installation of multiple boron substituents about the starting arene and then Ir catalyzed selective deborylation of the individual borons can allow for the formation of an even greater...
Show moreArylboronate esters are versatile synthetic building blocks. Iridium catalyzed C-H activation/borylation reactions are a green way of making such building blocks as these reactions often obviate the need for prior functionalization (e.g. halogenation), the use of pyrophoric reagents, cryogenic conditions, etc. Installation of multiple boron substituents about the starting arene and then Ir catalyzed selective deborylation of the individual borons can allow for the formation of an even greater diversity of borylated building blocks.The regioselectivity of Ir-catalyzed borylation is usually driven by sterics, however heterocycles are known to borylated at positions that exhibit heightened C-H acidity through the influence of the heteroatom. The regioselective borylation attained with a tryptophan derivative has been utilized in the development of a novel convergent route to the TMC-95 core. While pursuing a model synthesis of this natural product, the ability of bismuth salts to catalyze deborylations was discovered. These bismuth salts mediated methods can be highly selective in the in the deborylation of di and triborylated indoles. Furthermore, bismuths compounds are safe and less expensive as compared to the Ir-catalysts that facilitated deborylation. Numerous screening experiments on both substrates and other metal salts afforded a better understanding of how these novel deborylations can be applied in various synthetic settings and provided insight into possible mechanisms.Also, while I was a teaching assistant and a fixed-term instructor during my graduate studies at Michigan State University, I gradually realized that teaching is my passion and I am prepared to start my independent career and be an independent thinking teacher for the organic chemistry area.Owing to the nature of the subject, organic chemistry can be very visually distracting, and the image can be overpowering during student's learning. Like it or not students will try memorization first, our hypothesis is that once they know the "organic transformation formula" in words, via memorization or any other method, then introducing them to the structures of these functional groups will come with added context, and once they make that jump from word to structure they will be in a better position to understand reaction mechanisms. More importantly, understanding those reaction mechanisms will enable the student to progress to more complex topics.By introducing functional group transformations without the "clutter" of structures, we predict that once structures are introduced students will prioritize what's important because they will have trained their minds to ask what is the functional group, not "where did I see that structure in my notes".In short, we aim to train students to focus their attention on the reactive functional group of an organic molecule by emphasizing the use of WORDS to describe functional group transformation and teach the organic chemistry as the second language.
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Title: Labor market outcomes of restatements for corporate accountants
Creator: Shen, Lulu
Date: 2018
Collection: Electronic Theses & Dissertations
Description: This study examines the impact of restatements on the labor market outcomes for corporate accountants. I use LinkedIn to identify a comprehensive sample of corporate accountants who work for firms that restated their financial statements between 2004 and 2014. Using a difference-in-differences research design, I find that corporate accountants experience a higher turnover and a worse promotion prospect after restatements are announced, compared to a control sample of human resources...
Show moreThis study examines the impact of restatements on the labor market outcomes for corporate accountants. I use LinkedIn to identify a comprehensive sample of corporate accountants who work for firms that restated their financial statements between 2004 and 2014. Using a difference-in-differences research design, I find that corporate accountants experience a higher turnover and a worse promotion prospect after restatements are announced, compared to a control sample of human resources professionals within the same firm. The increase in turnover is more pronounced for senior internal auditors, and in firms with more severe restatements. I also find that senior internal auditors experience a higher turnover but not a worse promotion prospect before restatements are announced, compared to senior corporate accountants. Overall, my findings suggest that corporate accountant experience adverse labor market outcomes after restatements are announced. Internal auditors could minimize the adverse labor market outcomes of restatements by proactively departing.
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