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Title: Market discipline, integrity, information disclosure and financial misconduct
Creator: Li, Qingqiu (Graduate of Michigan State University)
Date: 2018
Collection: Electronic Theses & Dissertations
Description: In my dissertation, I explore the factors which impact the outcome of financial misconduct. Financial misconduct imposes negative externalities on firm value, influences investment decisions, and results in both wealth transfer and destruction. The unique governance structure in the asset management industry amplifies the role of investors on firm behavior. I provide novel evidence on the variation in response towards enforcement actions by investor types; I find evidence consistent with two...
Show moreIn my dissertation, I explore the factors which impact the outcome of financial misconduct. Financial misconduct imposes negative externalities on firm value, influences investment decisions, and results in both wealth transfer and destruction. The unique governance structure in the asset management industry amplifies the role of investors on firm behavior. I provide novel evidence on the variation in response towards enforcement actions by investor types; I find evidence consistent with two non-mutually exclusive explanations for this heterogeneity. First, investor sophistication affects the effective cost of information acquisition and processing, making the fund flow discipline less prevalent for retail investors. Second, investors are less likely to punish funds when the costs of moving capital become substantial. Besides investors, other market participants also significantly affect firm behavior. Internal factors, such as corporate culture, along with external factors, such as product market competition, have significant impact on corporate fraud. For example, a lack of focus on integrity in corporate culture is associated with unethical corporate behavior, cultures that neglect integrity are associated with a greater probability of SEC enforcement actions for accounting misstatements. In addition, firms with lower product market differentiation exhibit significantly lower rates of fraud; the relationship is more pronounced for complex firms and is robust to controlling for various measures of competition, predictors of fraud, and industry heterogeneity. Overall, the findings suggest that lower differentiation disciplines firms by facilitating fraud detection through a benchmarking channel.
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Title: Statistical inference with high-dimensional dependent data
Creator: Santo, Shawn M.
Date: 2018
Collection: Electronic Theses & Dissertations
Description: High-dimensional time dependent data appear in practice when a large number of variables are repeatedly measured for a relatively small number of experimental units. The number of repeated measurements can range from two to hundreds depending on the application. Advances in technology have made the process of gathering and storing data such as these relatively low-cost and efficient. Demand to analyze such complex data arises in genetics, microbiology, neuroscience, finance, and meteorology....
Show moreHigh-dimensional time dependent data appear in practice when a large number of variables are repeatedly measured for a relatively small number of experimental units. The number of repeated measurements can range from two to hundreds depending on the application. Advances in technology have made the process of gathering and storing data such as these relatively low-cost and efficient. Demand to analyze such complex data arises in genetics, microbiology, neuroscience, finance, and meteorology. In this dissertation, we first introduce and investigate a novel solution to a classical problem that involves high-dimensional time dependent data. In addition, we propose a new approach to analyze high-dimensional dependent genomics data.First, we consider detecting and identifying change points among covariance matrices of high-dimensional longitudinal data and high-dimensional functional data. The proposed methods are applicable under general temporospatial dependence. A new test statistic is introduced for change point detection, and its asymptotic distribution is established under two different asymptotic settings. If a change point is detected, an estimate for the location is provided. We investigate the rate of convergence for the change point estimator and study how it is impacted by dimensionality and temporospatial dependence in each asymptotic framework. Binary segmentation is applied to estimate the locations of possibly multiple change points, and the corresponding estimator is shown to be consistent under mild conditions for each asymptotic setting. Simulation studies demonstrate the empirical size and power of the proposed test and accuracy of the change point estimator. We apply our procedures on a time-course microarray data set and a task-based fMRI data set. In the second part of this dissertation we consider a hierarchical high-dimensional dependent model in the context of genomics. Our model analyzes RNA sequencing data to identify polymorphisms with allele-specific expression that are correlated with phenotypic variation. Through simulation, we demonstrate that our model can consistently select significant predictors among a large number of possible predictors. We apply our model to an RNA sequencing and phenotypic data set derived from a sounder of swine.
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Title: Quantifying groundwater recharge dynamics using a process-based distributed hydrologic model
Creator: Kang, Guoting
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Groundwater--the lifeblood of groundwater-dependent ecosystems and societies--is facing unprecedented threats from over-extraction, contamination, and changing climate. Groundwater recharge provides a sustainable source of water for aquifers and plays an important role in both surface and sub-surface domains. Understanding and accurately estimating the rate, location, and timing of major recharge events and their seasonal and inter-annual variability is key to safely matching societal needs...
Show moreGroundwater--the lifeblood of groundwater-dependent ecosystems and societies--is facing unprecedented threats from over-extraction, contamination, and changing climate. Groundwater recharge provides a sustainable source of water for aquifers and plays an important role in both surface and sub-surface domains. Understanding and accurately estimating the rate, location, and timing of major recharge events and their seasonal and inter-annual variability is key to safely matching societal needs of water and to maintaining healthy groundwater-dependent ecosystems. This work attempts to understand and quantify recharge dynamics in an agricultural watershed in the Ottawa County, Michigan using field observations of baseflows, groundwater heads, satellite-based evapotranspiration (ET) products and an integrated, process-based hydrologic model. Specific objectives of the work are to: (1) understand the spatial and temporal distribution of high- and low-recharge events and (2) assess the relative impacts of climate, land use, soils, and topography on the spatiotemporal distribution of recharge within the region. County-wide synoptic and time-series baseflow data collected from over 40 small streams between July and November of 2015 were used to quantify the uncertainties in recharge estimation. Precipitation data represent important inputs to hydrologic models and have a major influence on model performance and the estimated recharge. Compared to data from a typical network of rain gauges, the Next-Generation Weather Radar (NEXRAD) provides precipitation data at a much higher spatial resolution. NEXRAD data were blended with traditional rain gauge data to estimate recharge and to evaluate differences relative to recharge estimated using rain gauge data alone. Results indicate that caution should be exercised in using NEXRAD precipitation data for recharge estimation. The representation of recharge and its variability within a numerical model are closely related to the representation of meteorological forcing fields and their spatial structure, land use and land cover, the hydraulic properties of underlying soils and aquifers as well as topography--all of which are represented to varying degrees of accuracy depending on the mesh resolution employed and the algorithms used to represent sub grid-scale processes. To understand the effects of grid resolution on recharge and to identify optimal resolution relative to the size of the watershed, models were setup with different grid resolutions. Recharge patterns follow precipitation patterns more closely at coarse grid sizes since the characteristics of LULC, terrain and hydraulic properties are smoothed at this resolution. Insights gained from the study are expected to aid in the sustainable management of natural resources, particularly groundwater-dependent ecosystems.
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Title: Environmental assessment of transparent photovoltaics
Creator: Lee, Eunsang
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Transparent organic photovoltaics (TPV) can harvest energy from the near-infrared (NIR) and ultraviolet region of the solar spectrum and could be used in new applications such as windows. In addition to producing electricity, the transparent organic solar cell absorbs in the NIR region and could reduce the cooling energy demand of buildings during summer. Organic photovoltaic (OPV) is an emerging technology, developed mostly to replace fossil fuel energy, aimed to reduce greenhouse gases...
Show moreTransparent organic photovoltaics (TPV) can harvest energy from the near-infrared (NIR) and ultraviolet region of the solar spectrum and could be used in new applications such as windows. In addition to producing electricity, the transparent organic solar cell absorbs in the NIR region and could reduce the cooling energy demand of buildings during summer. Organic photovoltaic (OPV) is an emerging technology, developed mostly to replace fossil fuel energy, aimed to reduce greenhouse gases emissions. As OPV technology is reaching commercialization, it is essential to quantify its environmental impacts and ensure that new issues are not created. Life cycle assessment (LCA) is often used to compare energy technologies and identify environmental concerns, but this process is challenging for emerging technologies due to lack of inventory data. To guide future transparent OPV development, this work (1) demonstrates a new iterative methodology to evaluate and guide OPV material manufacturing that combines LCA and green chemistry approaches, (2) evaluates the energy saving from organic TPV in window and skylight applications in various cities, and (3) assesses the impact of organic TPV on urban heat island effect.The methodology was used to identify “hotspots,” which correspond to the processes that have the highest impact for chloroaluminum phthalocyanine (ClAlPc) manufacturing. An optimized process that reduces the environmental impact by 3%, the cost by 9% and chemicals hazard by 23% compared to the current process was demonstrated. The impact of TPV during the use phase was studied using ClAlPc based devices in window application. The building energy performance was shown to improve by up to 20 % due to heating and cooling energy saving. The energy saving varies with climate since NIR absorption by TPV in a window is more efficient in a warmer climate. The use of TPV in the window application in an urban area could further reduce the energy demand of buildings. The net energy saving by the TPV application in the urban area was calculated to be higher than in rural area by up to 2 GJ per month.
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Title: Viruses in water and wastewater and their significance to public health
Creator: O'Brien, Evan Patrick
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Viruses are responsible for millions of disease cases and deaths each year worldwide. Water-related viruses are of particular concern to environmental engineers, especially with regards to wastewater. Wastewater can be a valuable tool in the investigation of viral disease. This dissertation seeks to study the presence, quantification, and diversity of viruses in wastewater in the application of various methodologies for the protection of human, animal, and environmental health.

Title: Sweet nanomedicine in vivo : glyconanoparticle for imaging amyloid beta fibrils in Alzheimer's disease, and hyaluronan nanoparticles for imaging and therapy of inflammatory Atherosclerosis disease
Creator: Hossaini Nasr, Seyedmehdi
Date: 2018
Collection: Electronic Theses & Dissertations
Description: This dissertation is about design and synthesis of glyconanoparticles for certain in vivo applications including imaging amyloid beta fibrils in Alzheimer’s disease, imaging inflammatory atherosclerotic plaques and inhibition of atherosclerotic plaque inflammation. Amyloid beta (Aβ) accumulation and deposition in the brain tissue are one of the most important hallmarks of Alzheimer’s disease (AD). Therefore, Aβ is an attractive target for imaging AD, however, designing a nanoprobe with the...
Show moreThis dissertation is about design and synthesis of glyconanoparticles for certain in vivo applications including imaging amyloid beta fibrils in Alzheimer’s disease, imaging inflammatory atherosclerotic plaques and inhibition of atherosclerotic plaque inflammation. Amyloid beta (Aβ) accumulation and deposition in the brain tissue are one of the most important hallmarks of Alzheimer’s disease (AD). Therefore, Aβ is an attractive target for imaging AD, however, designing a nanoprobe with the ability to pass through the blood brain barrier (BBB) and reaching Aβ plaques is a significant challenge. The first part of this dissertation covers the synthesis of a glyconanoparticle enabling to pass the BBB and bind with Aβ fibrils. Briefly, synthesis, characterization and application of this glyconanoparticle for magnetic resonance imaging (MRI) of Aβ plaques in a mouse model of AD (B6C3) have been presented. Majority of patients that experience cardiac arrests have atherosclerosis, which is the inflammatory disease of arterial walls and the major cause of heart attacks and strokes. Imaging techniques that can enable detection of atherosclerotic plaques before clinical manifestation are urgently needed. CD44 is a cell surface protein overexpressed in the plaque tissues and its expression level is associated with the risk of plaque rupture. The second chapter explains atherosclerosis disease and nanomedicine for targeting inflammatory atherosclerotic plaques. The third chapter of this dissertation presents the development of hyaluronan (HA) coated iron oxide nanoparticles for active targeting of the plaques. These nanoprobes can not only bind with atherosclerotic plaques through their HA ligands but also function as T2 based MRI contrast agents for plaque diagnosis. Moreover, the effect of nanoprobe morphology on inflammation has been studied indicating that engineering nanoprobe shape could decrease inflammatory responses, which makes it a superior candidate for imaging inflammatory atherosclerotic plaques. Concisely, design and synthesis of HA conjugated nanoworm (HA-NW) have been explained. Then, inflammatory responses to HA conjugated nanoparticles in vitro and in vivo in apoE knockout mouse model have been presented. Finally, the ability of HA-NW for in vivo imaging of atherosclerotic plaques by MRI has been studied.The last part of this dissertation goes over design and synthesis of hyaluronan conjugated atorvastatin nanoparticle (HA-ATV NP). This therapeutic formulation has been designed to deliver ATV to the inflammatory atherosclerotic plaques to reduce plaque inflammation. Then, HA-ATV NP anti-inflammatory effects in vitro and its therapeutic effect in vivo in apoE knockout mouse model have been explained. It has been shown that intravenous administration of this formulation (high dose, 8.5 mg ATV/ kg), every other day for one week can significantly reduce the plaques inflammation.
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Title: MANAGEMENT AND CHARACTERIZATION OF ALTERNARIA SPP. AND SEEDBORNE PATHOGENS ASSOCIATED WITH AMERICAN GINSENG (PANAX QUINQUEFOLIUS) GARDENS IN WISCONSIN
Creator: Neils, Amber L.
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Leaf blight, caused by Alternaria panax, is a yearly challenge for those who cultivate ginseng, requiring frequent fungicide applications to protect valuable yield. In this study, the incidence and pathogenicity of Alternaria spp. on American ginseng in Wisconsin and effective leaf blight-controlling strategies were assessed. Five hundred and ninety-two isolates of Alternaria spp. were obtained from leaves (491), drupes (88) and seeds (10) of ginseng between 2011 and 2015. Resistance to...
Show moreLeaf blight, caused by Alternaria panax, is a yearly challenge for those who cultivate ginseng, requiring frequent fungicide applications to protect valuable yield. In this study, the incidence and pathogenicity of Alternaria spp. on American ginseng in Wisconsin and effective leaf blight-controlling strategies were assessed. Five hundred and ninety-two isolates of Alternaria spp. were obtained from leaves (491), drupes (88) and seeds (10) of ginseng between 2011 and 2015. Resistance to azoxystrobin was determined using an amended agar plate assay and a molecular assay that detected a common mutation responsible for strobilurin resistance in fungi. The majority (74.5%) of the isolates were identified as small-spored Alternaria spp. and their pathogenicity was confirmed using a detached leaf assay. Wounding increased the occurrence of infection by small-spored Alternaria spp. although infection occasionally (<6%) occurred without wounding. Alternaria panax was consistently pathogenic; lesion area resulting from A. panax and small-spored Alternaria spp. infection ranged from 4.34 to 28.88 mm2 and from 0.04 to 27.72 mm2, respectively. Results from the plate assay show 65.2% of A. panax isolates and 82.6% of small-spored Alternaria spp. isolates were classified as resistant to azoxystrobin at an EC50 of greater than 4.00. Leaf blight-control strategy field trials were conducted in commercial ginseng gardens over two years. One trial compared fourteen fungicides (boscalid, chlorothalonil, cyprodinil+fludioxonil, famoxadone+cymoxanil, penthiopyrad, fluazinam, pyraclostrobin, difenoconazole+azoxystrobin, pyrimethanil, fluxapyroxad+pyraclostrobin, difenoconazole, extract of giant knotweed, mancozeb, and azoxystrobin) and a non-treated control. In a second trial, a disease forecaster program, TOM-CAST, with spray thresholds of 10 or 15 disease severity values (DSVs) was tested. Penthiopyrad, difenoconazole, fluazinam, difenoconazole+azoxystrobin and pyraclostrobin limited disease incidence compared to the control (P < 0.05). Applications of pyraclostrobin and mancozeb resulted in a higher seedhead yield than the control, the highest number of healthy drupes and the lowest number of diseased drupes (P < 0.05). In the forecasting trial, the disease severity rating of TOM-CAST 10 DSV plots was similar to those treated every 10 days, but higher than for plots treated every 7 days. The TOM-CAST 15 DSV plots were severely diseased. Yields were similar among plots treated every 7 days and according to TOM-CAST 10 DSV.The establishment costs of a ginseng planting are high and seed health is an important consideration. Because of this, fungal presence on drupes, green seed coats, and endosperms was surveyed using a plate assay. A field trial to assess seed treatments in commercial ginseng gardens included stratified seed treated with the fungicides penthiopyrad, oxathiapiprolin, fluopicolide, ethaboxam, captan, mefenoxam + fludioxonil, or azoxystrobin. Alternaria spp. were commonly isolated from drupes and green seed coat and Fusarium spp. were recovered from all seed parts, including the endosperm. Cylindrocarpon destructans was only recovered in low numbers on green seed coats. Although none of the treatments significantly increased final plant stand compared to the control, oxathiapiprolin and azoxystrobin resulted in the highest plant stands throughout the season in year one (P < 0.05). In year two the control and fluopicolide resulted in the highest final plant stands (P < 0.05).
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Title: News organizations' news link sharing strategies on Twitter : economic theory and computational text analysis
Creator: Pak, Chankyung
Date: 2018
Collection: Electronic Theses & Dissertations
Description: This dissertation explores news organizations' social media strategies to disseminate their news stories as emergent quasi-editorial decisions. As in traditional editorial decisions, how news organizations share their news links on social media determines the visibility of certain stories and makes certain aspects of news stand out or be unobtrusive. By illustrating how these practices on Twitter resemble and deviate from traditional ones, I argue that social media open up a new path by which...
Show moreThis dissertation explores news organizations' social media strategies to disseminate their news stories as emergent quasi-editorial decisions. As in traditional editorial decisions, how news organizations share their news links on social media determines the visibility of certain stories and makes certain aspects of news stand out or be unobtrusive. By illustrating how these practices on Twitter resemble and deviate from traditional ones, I argue that social media open up a new path by which news organizations mediate news information, relatively free from journalistic norms and routines embedded in the older media and traditional editorial processes.To answer a fundamental question, ?Is there a reason for a news organization to be strategic on social media?? I presented an economic model based on competition for limited attention of social media users. In this model, the scarcity of users' attention capacity relative to the volume of information propagated via social media creates competition between news\ organizations. The model illustrates that one news organization's attempt to capture users' attention undermines the chance for other organizations to do so. Thus, a news organization should strategically decide how many news links it is going to share considering how many others would share. A simple empirical test confirms the model's prediction that news organizations will reduce the proportion of news links they share on social media as more news is published by all organizations. Computational text analyses shed light on the more qualitative aspects of news dissemination strategies on social media. First, using a recently developed machine learning technique, Structural Topic Model (STM), I investigate news organizations' selective news link sharing as a new layer of gatekeeping. The result indicates that the common concern that commercialized media drives news toward human interest rather than newsworthiness is crystallized more visibly on Twitter than on news websites. Further, a comparison of the selective link sharing across different media types shows that topic selection differs depending on a given topic's popularity on Twitter and a news organization's specialty in the topic. Even though a news organization may consider a certain topic to be important in its editorial decision, so that the organization has become specialized in that topic throughout its history, it would not share much about the topic on Twitter because popularity in the short term dominates link sharing strategies.I found that regional media convey less negative sentiment through news stories than other types of news organizations. This seems to be associated with the less controversial news topics they frequently cover compared to national and online media. However, news paraphrasing for Twitter homogenizes emotional framing across different types of organizations. In particular, regional media catch up to other types by adding even more negativity on news paraphrases for Twitter. This finding provides another significant indication that social media strategies are governed by different logic than that which governs traditional editorial practices. Major empirical findings provide evidence that the social media strategies of news organizations are already functioning as a separate information-mediating process. I argue that the distinctiveness of social media strategies as quasi-editorial decisions raises a practical need to publicly monitor news organizations' behaviors on social media to learn whether they will provide news that is informative and diverse enough for news readers' informed decisions. The automated data collection schemes and computational text analysis techniques I adopted in this dissertation will inform the design of infrastructure for such public monitoring.
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Title: Promoting prospective teachers' enactment and appropriation of new instructional strategies in their field placements
Creator: Hinojosa, Denisse M.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "Prospective teachers experience the complexity of teaching from the moment they start their field placement. Experiencing this complexity without adequate professional guidance could prevent prospective teachers from enacting in practice what is learned in teacher preparation programs. In this dissertation, I explore the ways in which I used onsite coaching moves such as modeling and dialogic feedback in my work coaching two elementary interns throughout their participation in a professional...
Show more"Prospective teachers experience the complexity of teaching from the moment they start their field placement. Experiencing this complexity without adequate professional guidance could prevent prospective teachers from enacting in practice what is learned in teacher preparation programs. In this dissertation, I explore the ways in which I used onsite coaching moves such as modeling and dialogic feedback in my work coaching two elementary interns throughout their participation in a professional development program to appropriate instructional strategies for differentiating instruction in general education classrooms. I seek to understand interns' responses to these coaching moves and implications on the development of interns' teaching practice. In Chapter One, I explore the IDEAL framework which helped me understand how the onsite coaching cycle. In Chapter Two, I explore the types of feedback provided on lesson plans and planning sessions to support teacher learning. In Chapter Three, I explore onsite modeling and dialogic feedback to scaffold prospective teachers' enactment of new instructional strategies. In Chapter Four, I share an approach to onsite coaching that has implications for field supervision to support prospective teachers' enactment and appropriation of new instructional strategies in their field placements. All chapters are related to exploring prospective teachers' enactment and appropriation of new instructional strategies in the context of developing their teaching practice."--Page ii.
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Title: Integrating genomic selection and genome editing strategies to accelerate potato breeding
Creator: Enciso Rodriguez, Felix Eugenio
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "As a staple food, the potato (Solanum tuberosum L.) plays an important role in human nutrition and it is currently the third most important food crop after rice and wheat. However, the potato crop faces high production losses caused mainly by biotic factors. With the advent of cutting-edge technologies suitable for potatoes, there is an increasing possibility to accelerate genetic progress and variety generation. To contribute to the implementation of genomic strategies to accelerate potato...
Show more"As a staple food, the potato (Solanum tuberosum L.) plays an important role in human nutrition and it is currently the third most important food crop after rice and wheat. However, the potato crop faces high production losses caused mainly by biotic factors. With the advent of cutting-edge technologies suitable for potatoes, there is an increasing possibility to accelerate genetic progress and variety generation. To contribute to the implementation of genomic strategies to accelerate potato breeding, three different approaches were used. First, whole genome regressions were conducted using additive and dominant allele dosage models for late blight and common scab resistance in tetraploid potatoes. Multiple Single Nucleotide Polymorphisms (SNPs), contribute to late blight resistance, uncovering the introgression history for this trait whereas an unreported locus with a sizable contribution to common scab resistance was detected. Prediction accuracy assessments demonstrated that 90% of the genetic variance could be captured with an additive model, demonstrating the applicability of genomic prediction for tetraploid potato breeding. Second, a genome editing approach was implemented to breakdown the S-RNase -based self incompatibly in diploid potatoes. New S-RNase allelic variants, with flower-restricted expression, were identified in two self-incompatible (SI) diploid potatoes and mapped to chromosome I in a low recombination region. A dual single-guide RNA strategy was used to generate S-RNase knock-out lines producing premature stop codons on each targeted S-RNase allele. Self-compatibility was achieved in T0 knock-outs and stable transmitted to T1 lines. Additionally, Cas-9 free plants were also obtained. Plasticity in the self-compatible response was also observed in wild-type lines, presumably associated with non-stylar and environmental factors. Third, validation of the IPI-O4 -mediated suppression of the RB-based late blight resistance was conducted using in vivo and in vitro approaches. The hypersensitive response (HR) was confirmed when IPI-O1 was co-infiltrated with the RB gene from Solanum bulbocastanum using a heterologous system. However, HR was observed when IPI-O1 and IPI-O4 were infiltrated in transgenic potato lines carrying a synthetic RB gene containing a Coiled-Coil (CC) domain from S. pinnatisectum. Further work should be conducted to confirm this un-reported interaction. Similarly, we could not validate CC-dimerization using yeast-two hybrid assays and therefore more extensive experiments should be conducted to confirm this result. Ultimately, these genomic approaches open a new window to accelerate the generation of new potato varieties. Genomic selection strategies along with targeted mutagenesis will expand the boundaries of both approaches, reducing the potato breeding cycle considerably while maintaining genetic diversity, and providing access to genomic regions with low or null recombination in potatoes."--Pages ii-iii.
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Title: Design of a light-weight automobile carrying freight car
Creator: Stevens, John Bassett, Jr.
Date: 1948
Collection: Electronic Theses & Dissertations

Title: LMX comparisons between peers : a relational approach to studying LMX differences and interpersonal behaviors
Creator: Yu, Andrew
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "To date, a disproportionate amount of research examining the importance of leader-member work relationships has focused on the outcomes for individual employees. However, there has been criticism regarding the myopic focus on the leader-member dyad and failing to consider the broader implications on system of social relationships each LMX relationships is embedded within. This has led to an emerging literature focused on understanding the effects of differences in LMX relationships. In this...
Show more"To date, a disproportionate amount of research examining the importance of leader-member work relationships has focused on the outcomes for individual employees. However, there has been criticism regarding the myopic focus on the leader-member dyad and failing to consider the broader implications on system of social relationships each LMX relationships is embedded within. This has led to an emerging literature focused on understanding the effects of differences in LMX relationships. In this dissertation, I leverage power-approach theory to integrate psychological research on power with extant research on LMX and differences in LMX relationships. Specifically, I argue that that perceived differences in a focal employee's LMX quality to that of a referent coworker will influence his or her sense of psychological power. The extent that the focal employee and referent coworker are task interdependence will moderate this relationship. Subsequently, the effects of LMX differences will influence discretionary interpersonal work behaviors (mediated through psychological power). However, the form of discretionary behavior (i.e., citizenship vs. counterproductive) will be contingent upon the individual characteristics of the focal employee."--Page ii.
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Title: Homeostatic responses of the enteric cholinergic system in stress and enteritis
Creator: Pohl, Calvin Seneca
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Stressful, traumatic events are a well-recognized trigger leading to acute and chronic gastrointestinal (GI) disease like Irritable Bowel Syndrome (IBS) or Inflammatory Bowel Disease (IBD). Two major types of stress which are pervasive within the world population are early life adversity and depression, both of which are strongly associated with GI disease throughout life. Though much of the underlying pathology in IBS and IBD has been described, the underlying mechanisms explain how stress...
Show moreStressful, traumatic events are a well-recognized trigger leading to acute and chronic gastrointestinal (GI) disease like Irritable Bowel Syndrome (IBS) or Inflammatory Bowel Disease (IBD). Two major types of stress which are pervasive within the world population are early life adversity and depression, both of which are strongly associated with GI disease throughout life. Though much of the underlying pathology in IBS and IBD has been described, the underlying mechanisms explain how stress may trigger onset or increased symptom severity in these chronic disease is poorly understood. The enteric cholinergic nervous system is a major regulator of GI homeostasis with broad regulatory roles over epithelial barrier permeability, epithelial cell secretion, smooth muscle contraction and motility, and immune activation. Though a role of the enteric nervous system has been describe in acute stress induced GI dysfunction, little is known about the role of this system in chronic stress, early life adversity, or in infectious models. The objective of this dissertation was to determine if the enteric cholinergic nervous system contributed to GI disease under different types of environmental challenges including early life adversity, chronic stress and pathogen challenge. To answer these questions, we utilized several different small and large animal models in combination with pharmacological agonists and antagonist of the cholinergic system. The results presented here demonstrate that different types of stressors differentially impact the enteric cholinergic system. Following early life adversity, we observed a persistent upregulation of the enteric cholinergic system, which predisposes individuals to increased intestinal secretion, permeability, motility, and upregulation of stress related genes. In a pathogen challenge model, we observed an upregulation of a non-neuronal component of the enteric cholinergic system which correlated positively with disease severity. Finally we observed that chronic stress in adulthood results in a strong down regulation of the enteric cholinergic nervous system with reduced cholinergic mediated functional secretion. Combined these findings demonstrated that different modes of stress have dichotomous impacts the enteric cholinergic system, which differentially impact GI function. Future work should focus on the precise factors impacting the function and expression of the cholinergic system in order to develop better therapies to cope with stress induced GI disease.
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Title: Black female teachers' presence, perseverance, and promise : how educational leaders can combat teacher turnover trends
Creator: Stanley, Darrius A.
Date: 2018
Collection: Electronic Theses & Dissertations
Description: This dissertation explores the depth of the Black educator turnover problem in today’s public schools. Black educators across the country have experienced higher than average turnover rates, eroding the success of recent minority teacher recruitment efforts. This epidemic has left the field of teaching consistent with the status quo, white and female. More recent research reveals that Black female teachers are leaving the classroom at alarming rates. Research consistently highlights school...
Show moreThis dissertation explores the depth of the Black educator turnover problem in today’s public schools. Black educators across the country have experienced higher than average turnover rates, eroding the success of recent minority teacher recruitment efforts. This epidemic has left the field of teaching consistent with the status quo, white and female. More recent research reveals that Black female teachers are leaving the classroom at alarming rates. Research consistently highlights school leadership as a primary influence for Black teacher turnover. Together, the research and turnover statistics suggest that race and school leadership are primary factors contributing to the increased departure of Black female teachers. However, there is less qualitative understanding of the depth of these impacts on Black female teacher turnover. This study explores three distinct queries. 1. What factors do Black female teachers perceive as most influential to their decisions to stay or leave their schools? 2. What role do Black female teachers suggest race plays in their decisions to stay or leave their schools?3. What role do Black female teachers suggest school leadership plays in their decisions to stay or leave their schools?Fifteen Black female teachers’ voices, experiences and perspectives are centered in this study which leans upon phenomenological and case study methodologies. The primary data collection tools included interviews and documents. The participants represent a diverse sample of Black female teachers that range in teaching experience, contexts, personal background, and grade levels. Elements of Black Feminism in Education and Critical Race Feminism were used to guide analysis and more importantly highlight the unique intersectional identities of the participants. Three major themes emerged from the interviews that have contributed to participants’ career experiences: 1) the impact of racial, cultural and gendered identity; 2) the impact of school leadership; and 3) the impact of organizations. The findings from this study highlight the impact of intersectional identity on Black female teachers’ career journeys. It exposes the sacrifices and commitments they have to teaching that are heavily influenced by their raced, gendered and classed herstories. Further, the findings suggest that school leaders who have the awareness of Black female teachers’ social justice related commitments and the pledge to uplift their voices within schools are better positioned to retain them. This study also finds that when organizations lack the awareness of racial, cultural and gender related issues, Black female teachers become less satisfied in those organizations. At the center of this study is the need for school leaders to develop and sustain more inclusive organizations that consider the personal backgrounds and intersectional identities of Black female teachers, if they wish to retain them in today’s public schools. The results of this study suggest that school leaders must play a more intentional role in retaining Black female teachers. The results suggest that school leaders must willfully support Black female teachers’ social justice agendas and pedagogies on their terms. Also, school leaders must create organizational cultures that are conducive to the unique needs of Black female faculty. Finally, schools and school leaders must listen to the voices of Black female teachers as a mechanism to retain their presence in the classroom and to uplift underserved, specifically Black, students in the curriculum and the school.
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Title: Middlemen : making literature in the age of multimedia conglomerates
Creator: McGrath, Laura B.
Date: 2018
Collection: Electronic Theses & Dissertations
Description: In the 1980s and 90s, the publishing industry in the United States was transformed by a series of mergers and acquisitions, as long-standing houses were subsumed into international multimedia conglomerates to form what we now know as The Big Five—Hachette Book Group, HarperCollins, Macmillan, Penguin Random House, Simon and Schuster. Though conglomeration revolutionized the processes of literary production, scholars have paid little mind to these corporate practices. This dissertation...
Show moreIn the 1980s and 90s, the publishing industry in the United States was transformed by a series of mergers and acquisitions, as long-standing houses were subsumed into international multimedia conglomerates to form what we now know as The Big Five—Hachette Book Group, HarperCollins, Macmillan, Penguin Random House, Simon and Schuster. Though conglomeration revolutionized the processes of literary production, scholars have paid little mind to these corporate practices. This dissertation investigates the ways that literature is made today by focusing on the overlooked professionals shaping the field of contemporary literary production: Agents, Editors, Authors, and Distributors. Too often dismissed as mere bureaucratic functionaries, these middlemen are in fact powerful nodes between artist and corporation, and they force us to rethink the category of literary production as a form of corporate creativity. Exploring the influence of middlemen on contemporary literary forms, I blend computational methods, ethnography, literary history, and close reading to model a new method for analyzing the field of literary production. I reveal how these professionals operate as administrators of literary prestige and “corporate taste” today, shaping the form and content of contemporary fiction while providing access to mainstream publication and cultural consecration. I argue that contemporary fiction allegorizes the logic of the marketplace, even while critiquing the neoliberal corporatization of literary production.
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Title: An analysis of the restaurant landscape in the Detroit Metropolitan Area : travel behavior and spatial patterns of difference
Creator: Eckert, Jeanette Elizabeth
Date: 2018
Collection: Electronic Theses & Dissertations
Description: This dissertation examines the spatial pattern and density of fast food restaurants in the Detroit region, and uses the results of a travel survey to analyze what types of restaurants respondents travel to in an average week. These travel characteristics are explored relative to urban form and sociodemographics of the respondents. A primary contribution to the literature is the use of reported restaurant travel trips, as opposed to making assumptions based solely on proximity or density of...
Show moreThis dissertation examines the spatial pattern and density of fast food restaurants in the Detroit region, and uses the results of a travel survey to analyze what types of restaurants respondents travel to in an average week. These travel characteristics are explored relative to urban form and sociodemographics of the respondents. A primary contribution to the literature is the use of reported restaurant travel trips, as opposed to making assumptions based solely on proximity or density of nearby restaurants. The study area is the Detroit region, characterized by a wide range of socioeconomics, demographics, and urban forms in a relatively small geographic area. The study sites selected represent high- and low-density neighborhoods as well as areas of affluence and extreme poverty. The neighborhood study sites include two high-density, low-income neighborhoods in Detroit; two high-density, higher-income neighborhoods in Ann Arbor and Birmingham; and two low-density, high-income neighborhoods in Bloomfield Hills and West Bloomfield, for a total of six neighborhoods. Using data on the locations of licensed restaurants in the study region at the time of the survey (2007-08), fast food density was calculated in multiple ways, including per capita, per square mile, and per road mile. The results show that residents of the City of Detroit have a slightly higher exposure to fast food than suburban counterparts. More notable is that of all restaurants in a municipality, Detroit has a higher proportion that is fast food (22%), compared to 15% in the low-density suburbs and 13% in the high-density suburbs. Using 997 completed travel surveys, the analysis reveals stark differences in the types of restaurants visited by Detroit respondents compared to suburban respondents. The majority of all restaurant trips (77%) for Detroit respondents are to fast food establishments, compared to 22% in the low-density suburbs and 17% in the high-density suburbs. More than half (52%) of Detroit respondents report traveling to a fast food restaurant in an average week, compared to 16% in both the low-density and high-density suburbs. Thus, Detroiters are dining out to fast food about three times as often as their suburban counterparts, despite having only a slightly higher density and proportion of fast food restaurants. Additionally, higher-income respondents travel farther on average to dine out, and are less likely to travel to fast food. While there is little difference in characteristics relating to a likelihood to dine out to restaurants in general, there are significant differences when examining trips to fast food restaurants. One or more trips to fast food in an average week is related to a higher body mass index, fewer servings of vegetables, more servings of soft drinks, less vigorous exercise, and cigarette smoking. The connected street grid design, density, and mixed-use zoning that is often associated with good urban design, walkability, and better health outcomes can be found in the high-density study neighborhoods of urban Detroit and the suburbs of Ann Arbor and Birmingham. Yet despite similar urban form, the suburban communities are reporting a much lower prevalence of obesity, higher likelihood to engage in exercise, more ideal nutritional choices than Detroit. Further examination into these complex relationships is warranted in order to help alleviate the public health disparities we see around obesity and diet-related diseases.
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Title: Politics of epistemic dependence : an epistemological approach to gender-based asylum
Creator: Sertler, Ezgi
Date: 2018
Collection: Electronic Theses & Dissertations
Description: "My dissertation aims to build a bridge between analytic social epistemologies, feminist epistemologies, and refugee studies by bringing them into conversation on gender-based asylum cases, i.e. cases where gender-related persecution is the primary consideration for the determination of refugee status. It does so by using the concept of "epistemic dependence," which refers to our social mechanisms of reliance in the process of knowing, i.e. what we rely on and how we rely on it. In this...
Show more"My dissertation aims to build a bridge between analytic social epistemologies, feminist epistemologies, and refugee studies by bringing them into conversation on gender-based asylum cases, i.e. cases where gender-related persecution is the primary consideration for the determination of refugee status. It does so by using the concept of "epistemic dependence," which refers to our social mechanisms of reliance in the process of knowing, i.e. what we rely on and how we rely on it. In this dissertation, I argue that tracking problematic operations of epistemic dependence can provide an illuminating framework for understanding the epistemological impacts of the social and political structures that govern asylum claims." -- Abstract.
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Title: Modeling parasitic weed emergence across smallholder farming systems : the case of central Malawi
Creator: Silberg, Timothy Robert
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Four out of five households in Malawi rely on farming as a primary source of income, most of whom cultivate maize (Zea mays). Disconcertingly, 63-80% of maize yield losses among these households are attributed to the emergence of invasive and parasitic weeds such as Striga (Striga spp.). A plethora of Striga-control practices (SCPs) have been developed and disseminated to smallholder farmers (cultivating < 2 ha). These SCPs are commonly evaluated at agricultural research stations prior to...
Show moreFour out of five households in Malawi rely on farming as a primary source of income, most of whom cultivate maize (Zea mays). Disconcertingly, 63-80% of maize yield losses among these households are attributed to the emergence of invasive and parasitic weeds such as Striga (Striga spp.). A plethora of Striga-control practices (SCPs) have been developed and disseminated to smallholder farmers (cultivating < 2 ha). These SCPs are commonly evaluated at agricultural research stations prior to dissemination. Mixed results often arise later when they are implemented across the diverse agroecological and socioeconomic landscapes of smallholders. Many agree research will need to assess how SCPs perform under smallholder-conditions, and ultimately, how their uptake will affect emergence. The following dissertation is divided into three empirical studies. In the first essay, discrete choice experiments (DCEs) are used to estimate the percent of maize yield farmers are willing to sacrifice for different SCP attributes (e.g., labor, soil fertility). In the second essay, a seed bank stock and flow model (SB-SFM) is developed to assess emergence rates across different SCPs. In the final essay, results from the DCEs and SB-SFM are integrated within a system dynamics model (SDM) to simulate how environmental and socioeconomic parameters affect emergence across space and time. DCE findings highlight farmers are willing to sacrifice significant tradeoffs to implement SCPs that increase soil fertility and provide legumes. SB-SFM findings indicate the attachment phase and seed bank must simultaneously be addressed with multiple SCPs to suppress emergence over three to five years. Finally, alteration of different climate, farm-management and adoption parameters in the SDM underline that nutrient input subsidies and agricultural extension must be included in an aggregated effort to suppress the spread of Striga across the region.
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Title: THE ROLE OF JAZ PROTEINS IN THE REGULATION OF PLANT GROWTH-DEFENSE TRADEOFFS
Creator: Guo, Qiang
Date: 2018
Collection: Electronic Theses & Dissertations
Description: As sessile organisms, plants constantly experience challenges from the surrounding environment. In response to these biotic stresses, plants invest a prominent portion of their metabolic capacity in the production of defense-associated compounds and physical structures. However, expression of defense traits is often associated with growth restriction and ultimately reduces reproductive output. Although this growth-defense antagonism has a profound impact on plant biology and agricultural...
Show moreAs sessile organisms, plants constantly experience challenges from the surrounding environment. In response to these biotic stresses, plants invest a prominent portion of their metabolic capacity in the production of defense-associated compounds and physical structures. However, expression of defense traits is often associated with growth restriction and ultimately reduces reproductive output. Although this growth-defense antagonism has a profound impact on plant biology and agricultural practice, the mechanisms that regulate tradeoffs between growth and defense are poorly understood. The plant hormone jasmonate (JA) plays a dual role in enhancing immune responses and inhibiting growth. The JA signaling cascade is switched on when the bioactive form of the hormone is recognized by the COI1-JAZ co-receptor complex, which leads to the degradation of JAZ repressors via the SCFCOI1-26S proteasome pathway and subsequent relief of JA-responsive transcription factors (TFs). In this dissertation research, I first show that JAZ proteins promote growth and reproductive fitness in the model plant Arabidopsis thaliana by suppressing metabolic pathways for defense. Characterization of a jaz decuple (jazD) mutant defective in 10 JAZ genes revealed that hyperactivation of JA signaling significantly increased resource allocation to defense pathways, thereby improving plant resistance to insect herbivores and necrotrophic pathogens. The elevated defense of jazD was linked to carbon starvation, curtailed seed production and, under extreme conditions, lethality. Secondly, I show that the allocation costs associated with heightened JA responses in jazD was largely dependent on the bHLH-type TFs MYC2, MYC3 and MYC4, and that MYC2/3/4 played overlapping andconserved roles in metabolic reprogramming in jazD. Characterization of jazD myc mutants further showed that the JAZ-MYC transcriptional module controls the production of endoplasmic reticulum (ER)-derived structures called ER bodies, which are implicated in plant immunity. Finally, the jazD mutant was employed as a parental line in a genetic suppressor screen aimed at identification of novel mutations that uncouple growth-defense antagonism. Characterization of these suppressor of jazD (sjd) mutants revealed that JA signaling interacts with the red light signaling pathway to influence growth-defense balance. One sjd mutant (sjd56) not affected in red light signaling was also shown to partially uncouple growth-defense antagonism in jazD. Taken together, results from this dissertation provide evidence that growth-defense tradeoffs at low to moderate levels of defense are controlled by hardwired transcriptional networks, whereas high levels of defense inhibit growth through metabolic competition (allocation costs) between primary and secondary metabolism. Consistent with this view, JAZ proteins promote growth and reproductive fitness by preventing the negative effects of an unrestrained immune responses. The findings described in this dissertation may benefit the development of crop plants that are optimized for both growth and defense.
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Title: Carbohydrate-silica nanoparticles for sirna delivery : synthesis, characterization, and gene delivery
Creator: Chesniak, Olivia Mariel
Date: 2019
Collection: Electronic Theses & Dissertations
Description: RNA interference (RNAi) has long been pursued for its therapeutic potential. Sequence-specific knockdown of gene expression requires that small interfering RNA (siRNA) gain access to cellular cytoplasm, presenting difficulties for both the transport of nucleic acids to cells and their voyage across cellular membranes. Numerous materials are under development as siRNA delivery vehicles to address this need. The carbohydrate dextran has been incorporated into amine-functionalized sil- ica...
Show moreRNA interference (RNAi) has long been pursued for its therapeutic potential. Sequence-specific knockdown of gene expression requires that small interfering RNA (siRNA) gain access to cellular cytoplasm, presenting difficulties for both the transport of nucleic acids to cells and their voyage across cellular membranes. Numerous materials are under development as siRNA delivery vehicles to address this need. The carbohydrate dextran has been incorporated into amine-functionalized sil- ica nanoparticles (Dex-SiO2-NPs), enhancing their biocompatibility and success as siRNA delivery vehicles. Inspired by the work of Stober and others, reagent concentrations in the synthesis of Dex- SiO2-NPs have been adjusted to tune nanoparticle diameter. The size, shape, and morphology of Dex-SiO2-NPs have been characterized using transmission electron microscopy (TEM) and energy dispersive x-ray spectroscopy (EDS). These methods have revealed that Dex-SiO2-NPs decrease in silicon density toward their centers, when compared with SiO2-NPs. Thermal and porosity analysis were used to profile Dex-SiO2-NPs both containing dextran and after its removal by calcination. Having measured an increase in mesopores and decrease in micropores with calcination, it has been concluded that dextran serves as a porogen in Dex-SiO2-NP synthesis. Not only does dextran imbue these materials with unique morphology, it also enhances their function as delivery vehicles. Dex-SiO2-NPs improve enhanced green fluorescent protein (EGFP) supression compared to silica nanoparticles synthesized in the absence of dextran in human lung and kidney cells in vitro.
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