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Title: Essays in economic development
Creator: Ivanyna, Maksym
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The dissertation consists of three essays: "Benefits of diversification in agriculture: Evidence from Malawi", "Corruption and economic growth revisited" and "How close is your government to its people? Worldwide indicators on localization and decentralization". All three essays focus on issues, which are particularly important for developing countries: food security, corruption, decentralization.In the first essay I use data from a farmers' survey in Malawi to compare two agricultural...
Show moreThe dissertation consists of three essays: "Benefits of diversification in agriculture: Evidence from Malawi", "Corruption and economic growth revisited" and "How close is your government to its people? Worldwide indicators on localization and decentralization". All three essays focus on issues, which are particularly important for developing countries: food security, corruption, decentralization.In the first essay I use data from a farmers' survey in Malawi to compare two agricultural technologies: monoculture maize and crop diversification (maize-legume intercrop). I match farmers locations with data on rainfall and air temperature to test whether more biodiverse agriculture is better at absorbing weather shocks. The data make it possible to compare variation not only over time, but also over different plots within the same time period, which helps reduce omitted variable bias. The instrumental variable method is used to eliminate rainfall measurement error. For a number of specifications, and controlling for fertilizer use, crop diversification is both more productive than monoculture maize and more resistant to weather shocks. Although I am not able to identify the average population effect, I show that the effect I identify is likely to prevail if the Malawian government decides to shift the focus of its agricultural subsidy at the margin from fertilizer to legume seeds and education.The focus of the second essay is on corruption. While literature finds many channels through which corruption can hurt economic growth, the link proved hard to establish in empirical cross-country studies. In this paper I show that part of the explanation of this puzzle is that there is a reverse causality: everything else equal, exogenously-driven economic growth can increase corruption. The reason is that the boost to output increases tax revenue, and hence pool of resources that corrupt public officials can embezzle. I show the workings of this channel in a simple stylized model, which is then accompanied by numerical simulations in a dynamic general equilibium overlapping-generations model, which allows for corruption and tax evasion. I also present empirical evidence, which supports my findings.The third chapter assembles and analyzes a unique data base on local governance that provides a first approximation of the institutional architecture of local governance that has emerged as a result of the silent revolution (decentralization reforms) of the last three decades on moving governments closer to people. An important feature of this data set is that, for comparative purposes, it measures government decision making at the local level i.e. the order of government that is closest to the people and hence providing a better indicator of decentralized decision making as compared to the "sub-national governments" that also include intermediate tiers of provinces and states, used by the existing literature. This unique data set for 182 countries attempts to capture institutional dimensions of political, fiscal and administrative autonomy enjoyed by local governments under diverse multi-order governance regimes using a common framework. These dimensions are aggregated to develop a "decentralization index" and then adjusted for heterogeneity to develop a "government closeness index" that provides an overall ranking of countries on the closeness of their government to the people.
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Title: The design and synthesis of novel proteasome inhibitors : studies on the synthesis of nagelamide M and analogs, the synthesis of rapamycin based proteasome inhibitors, and the synthesis of TCH based molecular probes for binding site determination
Creator: Giletto, Matthew Basil
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The two primary physiologic mechanisms for the recycling of amino acids from no-longer needed or damaged proteins are autophagy and enzymatically via the proteasome. Inhibition of the proteasome has emerged as the preeminent means for treating cancers that constitutively overproduce proteins, particularly multiple myeloma. Two drugs currently available for the treatment of multiple myeloma, BortezomibTM and KyprolisTM, inhibit the proteasome by binding to the catalytically active sites...
Show more"The two primary physiologic mechanisms for the recycling of amino acids from no-longer needed or damaged proteins are autophagy and enzymatically via the proteasome. Inhibition of the proteasome has emerged as the preeminent means for treating cancers that constitutively overproduce proteins, particularly multiple myeloma. Two drugs currently available for the treatment of multiple myeloma, BortezomibTM and KyprolisTM, inhibit the proteasome by binding to the catalytically active sites through a competitive mechanism. While initially effective, over time the resistance that is typical of competitive binders emerges, and relapse rates are currently measured at 97 %, with the average survival time after being one year. Additionally the most common side effect is neuropathy, which typically does not abate after discontinuation of chemotherapy. The current state of the art demonstrates the need not only for new proteasome inhibitors, but inhibitors that act through a different mechanism. The Tepe group was the first to develop such a molecule, imidazolines of the TCH-series, which bind to the proteasome via a noncompetitive mechanism. The details of the interaction of these molecules with the proteasome have been extensively studied, but the location of the binding site remains elusive. In this work, several molecular probes were designed and synthesized (two diazirine photoaffinity-TCH hybrids and a biotin-TCH hybrid) to elucidate the location of the binding site. Currently biological testing is underway. Additionally, a library of analogs based on the natural product rapamycin were designed and synthesized. An analog was discovered that was equipotent to the natural product itself, which could be synthesized on a gram scale in three steps from commercially available materials. To discover the binding site of these molecules, a diazirine photoaffinity probe was designed and synthesized. Enough biological data was generated to refine the library and design and synthesize a second generation of the analogs; currently biological testing of these analogs is underway. Lastly, extensive studies on the total synthesis of the pyrrole-imidazole natural product nagelamide M were designed and performed. These studies relied mainly on the use of C-H activation to functionalize a methylene C-H bond adjacent to a heteroatom. None of the key reactions were successful, and the synthesis stalled at an early stage. Overall this thesis describes several advances in the areas of drug discovery and proteasome inhibition, and perhaps most excitingly access to molecules that could elucidate the binding site of the TCH molecules."--Pages ii-iii.
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Title: An individual differences approach to improving low target prevalence visual search performance
Creator: Peltier, Chad
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Critical real-world visual search tasks such as radiology and baggage screening rely on the detection of rare targets that may only be present on as few as .3% of searches (Gur et al., 2004). When targets are rare, observers search for a shorter amount of time and miss targets more often than when targets are common, a phenomenon known as the low prevalence effect (LPE). Given the real-world importance of the detection of low prevalence targets, researchers have attempted to improve search...
Show more"Critical real-world visual search tasks such as radiology and baggage screening rely on the detection of rare targets that may only be present on as few as .3% of searches (Gur et al., 2004). When targets are rare, observers search for a shorter amount of time and miss targets more often than when targets are common, a phenomenon known as the low prevalence effect (LPE). Given the real-world importance of the detection of low prevalence targets, researchers have attempted to improve search performance. There have been several experimental attempts to reduce the LPE, but none have been wholly successful, as even the best methods have increased hits at the cost of more false alarms. As an alternative to improving visual search performance through experimental manipulations, researchers have recently started using an individual differences approach to predict those who would be best at rare target detection. The individual differences approach has shown that it is possible to predict low prevalence target detection using working memory capacity (WMC) (Peltier & Becker, 2016b; Schwark et al., 2012) and moderate prevalence target detection using a personality assessment (Biggs, Clark, & Mitroff, 2017) and vigilance (Adamo, Cain, & Mitroff, 2016). Experiment 1 expands on the previous research by predicting low prevalence visual search performance using measures of WMC, near transfer high prevalence visual search accuracy, vigilance, attentional control, and introversion. The regression using these predictors accounts for 52% of the variance in accuracy. Experiment 2 addresses practical and theoretical limitations of Experiment 1 by replicating the original finding, including new potential predictors of low prevalence search performance (fluid intelligence, task unrelated thought frequency, and far transfer search accuracy), using more realistic search stimuli to increase external validity, and using eye tracking to investigate how individual differences relate to specific components of performance. The results show that near transfer search, far transfer search, WMC, introversion, and fluid intelligence account for 53% of the variance in accuracy in a more realistic low prevalence search. Using the beta weights from Experiment 1's significant predictors and each observer's score on the corresponding measures in Experiment 2, I find that the old predictors account for 42% of the variance in a novel search task's accuracy. Finally, the eye-tracking results show that we can significantly predict quitting thresholds (the number of items inspected before terminating search), selection error rates (misses caused by never inspecting the target), identification error rates (misses caused by misidentifying an inspected target), item re-inspection rates, target decision times, and distractor decision times. I conclude that the individual differences approach has the potential to be a highly effective tool in selecting those who are most likely to perform at a high level in real-world searches."--Pages ii-iii.
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Title: An agent model of vertical integration in telecommunications and content
Creator: Koning, Kendall Jay
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "This dissertation explores several important telecommunications policy issues in light of recent developments in the wireline broadband and online video markets." -- Abstract.

Title: Webbed space : online feminist discourse in the fourth wave
Creator: Sweo, Naomi
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "This thesis examines the feminist online discourse community 'A Practical Wedding' and identifies four characteristics that make it a model for feminist online interaction: 1. the connection of users' online identities with their real-life selves; 2. the non-hierarchical structure of the community; 3. the productive exchanges between members; and 4. the site- and Internet-wide intertextuality. Technofeminist threads in rhetoric and composition in the late 1990's and early 2000's were mostly...
Show more"This thesis examines the feminist online discourse community 'A Practical Wedding' and identifies four characteristics that make it a model for feminist online interaction: 1. the connection of users' online identities with their real-life selves; 2. the non-hierarchical structure of the community; 3. the productive exchanges between members; and 4. the site- and Internet-wide intertextuality. Technofeminist threads in rhetoric and composition in the late 1990's and early 2000's were mostly abandoned. They deserve renewed attention, with updating based on the existence and necessity of fourth-wave feminism today. The author first describes her own origin story that led to her interest in this research. She then applies a system of virtual critical discourse analysis and resultant coding schema to four representative posts and their comment sections. This thesis concludes with a call for the creation of more communitarian, feminist spaces on the Internet with similar models of engagement to those used in 'A Practical Wedding.'"--Page ii.
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Title: Conceptualizing gender, contextualizing curriculum : a case study of teacher education coursework
Creator: Kean, M. Eli
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This study explores and theorizes around issues of transgender curriculum in teacher education courses. Using a conceptual framework informed by both transgender theory and curriculum theory, I propose a Critical Trans Framework to analyze what trans-related curricular materials are currently used in teacher education courses and what factors influence teacher educators’ curricular choices. Gender-expansive syllabi were identified as those that contained required readings utilizing anti...
Show moreThis study explores and theorizes around issues of transgender curriculum in teacher education courses. Using a conceptual framework informed by both transgender theory and curriculum theory, I propose a Critical Trans Framework to analyze what trans-related curricular materials are currently used in teacher education courses and what factors influence teacher educators’ curricular choices. Gender-expansive syllabi were identified as those that contained required readings utilizing anti-oppressive, humanizing, intersectional, or justice-oriented characteristics. Data sources for this study include course syllabi, surveys with Likert-scale and open-ended questions, one-on-one interviews, and a group interview with all participants. Findings explore how participants were understanding or conceptualizing gender, queer, and heteronormativity in relation to trans. Participants had a somewhat similar approach to teaching gender as a concept, but had divergent and multiple understandings of queer. Heteronormativity was understood to be the overarching system of oppression targeting all non-heterosexual and non-cisgender people. In describing how they teach trans, the participants described attempts to complicate dominant trans narratives, establish class norms that created an environment ripe for gender exploration, and represent trans people through first-person narratives. Influential contextual elements outside the classroom include institutional and/or programmatic supports or constraints, the instructor’s own understanding and experience with transgender issues, and state or local policies.
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Title: Behavioral ecology of Amazonian mixed-species flocks
Creator: Williams, Sean M.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Amazonian mixed-species flocks of birds are remarkable by virtue of their strength of interspecific association. In these flocks, individuals of different species associate with each other for the duration of their lives, i.e. during all daylight hours, 365 days of the year across many years. These obligate relationships provide a unique opportunity to study the behavioral ecology of dependent interspecific relationships. I break my thesis into three chapters. First, I ask whether the...
Show moreAmazonian mixed-species flocks of birds are remarkable by virtue of their strength of interspecific association. In these flocks, individuals of different species associate with each other for the duration of their lives, i.e. during all daylight hours, 365 days of the year across many years. These obligate relationships provide a unique opportunity to study the behavioral ecology of dependent interspecific relationships. I break my thesis into three chapters. First, I ask whether the relationship between two obligatorily flocking species (nuclear antshrike and antwren species) is symmetrical and whether transient species (non-obligate flocking species) are equally attracted to the nuclear species. Are the transient species equally attracted to the two nuclear species? And are the two nuclear species equally attracted to each other? This first question was necessary to ask before my other questions because I needed to know which species are following other species and which species are being followed. Then, I ask whether the behavior of a single species (the same antshrike species I determined was mostly being followed in the first question) can predict the space use of the whole flock and what environmental and behavioral variables explain the space use. Finally, I ask whether a particular context-dependent vocalization of the antshrike might serve as a mechanism of interspecific cohesion of the flock. After having spent hundreds of hours studying the space use of flocks in order to define the spatial distribution of flocks within their territories, this last question followed naturally since the mechanism of interspecific cohesion was central to the coordination of the movement of the flock through space. In resident Amazonian mixed-species flocks, the pattern of attraction of transient species to nuclear antshrikes and antwrens, and the pattern of heterospecific attraction between the nuclear species, are undocumented. Patterns of attraction can help elucidate the nature of interspecific relationships, i.e. whether they are mutualistic, commensal, or parasitic. We played antshrike and antwren vocalizations to flocks and observed how many transient species approached the playbacks, whether antshrikes and antwrens were attracted to each others' playbacks, and how strongly they responded to the playbacks. More transient species were attracted to antshrike vocalizations than antwren vocalizations and more transient species were attracted to antwren than control vocalizations. Antshrikes and antwrens approached each others' playback significantly more often than they approached control playbacks; antwrens responded significantly more strongly to antshrike vocalizations than antshrikes did to antwren vocalizations. The primary reason transients are attracted to antshrikes may be the reliable alarm calling of the antshrikes, and the primary reason transient species are attracted to antwrens may be that antwrens serve as an indicator of a flock. Finally, antshrikes and antwrens likely confer benefits to each other, but those benefits may not be symmetrical. Investigating the drivers of space use is critical for understanding the ecology of a species. The drivers of space use patterns of multi-species groups have been studied seldom, although many avian species participate in mixed-species flocks throughout the world. We characterized the space use patterns of mixed-species flocks in Amazonian Peru and investigated the drivers of those patterns. We predicted that foraging and anti-predation behavior, i.e. attack rate, vigilance rate, and surrounding vegetation density of the "leader" Dusky-throated Antshrike (Thamnomanes ardesiacus) would explain the space use patterns of the whole flock. We found that low surrounding vegetation density, but not attack rate or vigilance rate, of the Dusky-throated Antshrike (Thamnomanes ardesiacus) explained a substantial amount of the space use patterns of the flock. The results are consistent with the hypothesis that a single species in these mixed-species flocks has a disproportionately large influence on space use decisions. The results may apply to other flocks worldwide that are led by species that behave similarly to the Dusky-throated Antshrike, for example Asian flocks led by drongos (Dicrurusspp.). Cohesion of interspecific associations requires communication among heterospecifics, although the mechanisms of communication are often unexplored. In many monospecific groups, cohesion among individuals is maintained with contact calls given in a certain context. We investigated whether such context-specific calls are responsible for the cohesion of mixed-species flocks of antshrikes and antwrens in Amazonian Peru. Dusky-throated Antshrikes (Thamnomanes ardesiacus) vocalize while in flight, and the number of times they vocalize covaries with the distance of the flight. Antwrens (Myrmotherula spp.) fly toward an antshrike sooner after the flight call than after a randomized control and another common vocalization not associated with flight. In addition, antwrens fly toward an antshrike sooner after a longer series of flight calls than after a shorter series. It remains unclear whether the antshrikes are deliberately signaling the antwrens or the antwrens are eavesdropping on the vocalizations, although signaling is possible since antshrikes may benefit from associating with antwrens through the dilution effect, confusion effect, and the many-eyes effect. The results suggest that the Dusky-throated Antshrike plays a critical role in maintaining Amazonian biodiversity through positive interactions with many species. Future conservation efforts should aim to conserve the Dusky-throated Antshrike, which likely has a disproportionately large positive effect on many avian species.
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Title: Multi-task learning and its application to geospatio-temporal data
Creator: Xu, Jianpeng
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Multi-task learning (MTL) is a data mining and machine learning approach for modeling multiple prediction tasks simultaneously by exploiting the relatedness among the tasks. MTL has been successfully applied to various domains, including computer vision, healthcare, genomics, recommender systems, and natural language processing. The goals of this thesis are: (1) to investigate the feasibility of applying MTL to geospatio-temporal prediction problems, particularly those encountered in the...
Show moreMulti-task learning (MTL) is a data mining and machine learning approach for modeling multiple prediction tasks simultaneously by exploiting the relatedness among the tasks. MTL has been successfully applied to various domains, including computer vision, healthcare, genomics, recommender systems, and natural language processing. The goals of this thesis are: (1) to investigate the feasibility of applying MTL to geospatio-temporal prediction problems, particularly those encountered in the climate and environmental science domains and (2) to develop novel MTL frameworks that address the challenges of building effective predictive models from geospatio-temporal data.The first contribution of this thesis is to develop an online temporal MTL framework called ORION for ensemble forecasting problems. Ensemble forecasting uses a numerical method to simulate the evolution of nonlinear dynamic systems, such as climate and hydrological systems. ORION aims to effectively aggregate the forecasts generated by different ensemble members for a future time window, where each forecast is obtained by perturbing the starting condition of the computer model or using a different model representation. ORION considers the prediction for each time point in the forecast window as a distinct prediction task, where the task relatedness is achieved by imposing temporal smoothness and mean regularization constraints. A novel, online update with restart strategy is proposed to handle missing observations in the training data. ORION can also be optimized for different objectives, such as ε -insensitive and quantile loss functions.The second contribution of this thesis is to propose a MTL framework named GSpartan that can perform inferences at multiple locations simultaneously while allowing the local models for different locations to be jointly trained. GSpartan assumes that the local models share a common, low-rank representation and employs a graph Laplacian regularization to enforce constraints due to the inherent spatial autocorrelation of the data. Sparsity and non-negativity constraints are also incorporated into the formulation to ensure interpretability of the models.GSpartan is a MTL framework that considers only the spatial autocorrelation of the data. It is also a batch learning algorithm, which makes it difficult to scale up to global-scale data. To address these limitations, a new framework called WISDOM is proposed, which can incorporate the task relatedness across both space and time. WISDOM encodes the geospatio-temporal data as a tensor and performs supervised tensor decomposition to identify the latent factors that capture the inherent spatial and temporal variabilities of the data as well as the relationship between the predictor and target variables. The framework is unique in that it trains distinct spatial and temporal prediction models from the latent factors of the decomposed tensor and aggregates the outputs of these models to obtain the final prediction. WISDOM also employs an incremental learning algorithm that can systematically update the models when training examples are available for a new time period or for a new location.Finally, the geospatio-temporal data for many scientific applications are often available at varying spatial scales. For example, they can be generated by computer models simulated at different grid resolutions (e.g., the global and regional models used in climate modeling). A simple way to handle the predictor variables generated from the multi-scale data is to concatenate them into a single feature vector and train WISDOM using the concatenated vectors. However, this strategy may not be effective as it ignores the inherent dependencies between variables at different scales. To overcome this limitation, this thesis presents an extension of WISDOM called MUSCAT for handling multi-scale geospatio-temporal data. MUSCAT considers the consistency of the latent factors extracted from the spatio-temporal tensors at different scales while inheriting the benefits of WISDOM. Given the massive size of the multi-scale spatio-temporal tensors, a novel, supervised, incremental multi-tensor decomposition algorithm is develop to efficiently learn the model parameters.
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Title: The effect of package dispenser and label on sunscreen application
Creator: Harben, Alyssa Lee
Date: 2017
Collection: Electronic Theses & Dissertations
Description: As skin cancer rates rise, sunscreen use is recommended as a way to decrease the risk of developing skin cancer. Studies show that most consumers of sunscreen do not apply the recommended amount of sunscreen to achieve full protection from UV rays. This study investigates the effect of using two different package dispenser types on human behavior in the context of sunscreen application in an effort to quantify differences in application volume. Additionally, labeling interventions designed to...
Show moreAs skin cancer rates rise, sunscreen use is recommended as a way to decrease the risk of developing skin cancer. Studies show that most consumers of sunscreen do not apply the recommended amount of sunscreen to achieve full protection from UV rays. This study investigates the effect of using two different package dispenser types on human behavior in the context of sunscreen application in an effort to quantify differences in application volume. Additionally, labeling interventions designed to either encourage or discourage application of sunscreen were placed on the bottle to test the effectiveness of using label messaging to influence application amounts. Participants were asked to apply sunscreen from different package styles to their arms and legs and complete a survey regarding the perceived risk of developing skin cancer and frequency of sunscreen use and other demographic factors. Results indicate that participants applied more sunscreen from the squeeze bottles than the pump bottles (p<.0001), and that there was no evidence of a discernable difference between different labels. Of the personal characteristics included in the model (including age, gender, skin tone saturation, history of sun burn, and study location) worry about developing skin cancer and frequency of sunscreen use were also significant at α=.05. The overall findings of this study was packaging design affects sunscreen application practices, but labeling warnings are less influential.
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Title: Example-Based Parameterization of Linear Blend Skinning for Skinning Decomposition (EP-LBS
Creator: Hopkins, Kayra M.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This thesis presents Example-based Parameterization of Linear Blend Skinning for Skinning Decomposition (EP-LBS), a unified and robust method for using example data to simplify and improve the development and parameterization of high quality 3D models for animation. Animation and three-dimensional (3D) computer graphics have quickly become a popular medium for education, entertainment and scientific simulation. In addition to film, gaming and research applications, recent advancements in...
Show moreThis thesis presents Example-based Parameterization of Linear Blend Skinning for Skinning Decomposition (EP-LBS), a unified and robust method for using example data to simplify and improve the development and parameterization of high quality 3D models for animation. Animation and three-dimensional (3D) computer graphics have quickly become a popular medium for education, entertainment and scientific simulation. In addition to film, gaming and research applications, recent advancements in augmented reality (AR) and virtual reality (VR) are driving additional demand for 3D content. However, the success of graphics in these arenas depends greatly on the efficiency of model creation and the realism of the animation or 3D image.A common method for figure animation is skeletal animation using linear blend skinning (LBS). In this method, vertices are deformed based on a weighted sum of displacements due to an embedded skeleton. This research addresses the problem that LBS animation parameter computation, including determining the rig (the skeletal structure), identifying influence bones (which bones influence which vertices), and assigning skinning weights (amounts of influence a bone has on a vertex), is a tedious process that is difficult to get right. Even the most skilled animators must work tirelessly to design an effective character model and often find themselves repeatedly correcting flaws in the parameterization. Significant research, including the use of example-data, has focused on simplifying and automating individual components of the LBS deformation process and increasing the quality of resulting animations. However, constraints on LBS animation parameters makes automated analytic computation of the values equally as challenging as traditional 3D animation methods. Skinning decomposition is one such method of computing LBS animation LBS parameters from example data. Skinning decomposition challenges include constraint adherence and computationally efficient determination of LBS parameters.The EP-LBS method presented in this thesis utilizes example data as input to a least-squares non-linear optimization process. Given a model as a set of example poses captured from scan data or manually created, EP-LBS institutes a single optimization equation that allows for simultaneous computation of all animation parameters for the model. An iterative clustering methodology is used to construct an initial parameterization estimate for this model, which is then subjected to non-linear optimization to improve the fitting to the example data. Simultaneous optimization of weights and joint transformations is complicated by a wide range of differing constraints and parameter interdependencies. To address interdependent and conflicting constraints, parameter mapping solutions are presented that map the constraints to an alternative domain more suitable for nonlinear minimization. The presented research is a comprehensive, data-driven solution for automatically determining skeletal structure, influence bones and skinning weights from a set of example data. Results are presented for a range of models that demonstrate the effectiveness of the method.
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Title: Refining trunk injection strategies for control of foliar insect pests and disease in Michigan apple orchards
Creator: Coslor, Charles Clark, 1988-
Date: 2017
Collection: Electronic Theses & Dissertations
Description: In conventional apple orchards, insect pests are managed with insecticides delivered to the canopy using airblast sprayers, which provide good canopy coverage. However, spraying results in significant product loss: as little as 26% is estimated to reach the tree canopy due to spray drift and less than 0.1% of insecticide ends up reaching the target pest. The remainder is lost to the environment with potential to harm people or non-target organisms. Trunk injection is a discriminating...
Show moreIn conventional apple orchards, insect pests are managed with insecticides delivered to the canopy using airblast sprayers, which provide good canopy coverage. However, spraying results in significant product loss: as little as 26% is estimated to reach the tree canopy due to spray drift and less than 0.1% of insecticide ends up reaching the target pest. The remainder is lost to the environment with potential to harm people or non-target organisms. Trunk injection is a discriminating pesticide delivery system which reduces insecticide inputs and environmental exposure by delivering chemicals directly to the vascular system. It is commonly used to deliver pesticides in ornamental and shade trees. Recent work with trunk injection in apple orchards has shown promise, but more research must be done to determine efficacy and safety in tree fruit crops. In the following studies, we injected emamectin benzoate, imidacloprid, dinotefuran, spinosad, chlorantraniliprole, and abamectin into apple trees to expand the list of insecticides compatible with trunk injection. Nectar and pollen were sampled from trees to compare the effects of injection timing on insecticide concentration in floral resources. In addition, two fundamental injection tool types were compared: drill-based and needle-based. To test compatibility of combined insect and disease management, an insecticide and a fungicide were injected simultaneously. Finally, low-volume injections were performed on nursery apple trees, which normally require high pesticide inputs and do not produce fruit for several years. Emamectin benzoate, chlorantraniliprole and abamectin resulted in moderate to high mortality and reduced feeding in Choristoneura rosaceana bioassays using leaves sampled from trunk injected apple trees. Neonicotinoids reduced Empoasca fabae density in field evaluations, and also showed activity on C. rosaceana at higher concentrations. Spinosad was not well-transported within the apple tree vascular system. Numbers of E. fabae nymphs were lower on trees injected with imidacloprid using a drill-based tool compared with untreated trees in all years, despite a trend of initially higher foliar concentrations with the needle-based tool. This demonstrated that delivery method is an important factor in effective trunk injection based apple management. We found that when an insecticide and a fungicide are injected, they can interact dynamically within the vascular system of a tree. Injections of emamectin benzoate followed by phosphorous acid into the same set of injection ports resulted in higher mortality of C. rosaceana larvae and lower incidence of apple scab compared with untreated trees. This has important implications for expanding the utility of trunk injection for fruit tree management. Nursery tree injections were most effective when emamectin benzoate was injected into the trunk versus the taproot. A rate equivalent to 1/8 the rate used for mature tree injection reduced insect pests more than a 1/80 rate. The higher rate of emamectin benzoate was also persistent in the following year. Imidacloprid and emamectin benzoate were injected in the spring and fall, and nectar and pollen were sampled the following spring. Imidacloprid was not detected in nectar or pollen when injected in the previous spring. Conversely, emamectin benzoate was detected when injected in the previous spring, but was not detected in nectar or pollen when injected in the fall. This study expanded the list of insecticides compatible with trunk injection, demonstrated novel uses of trunk injection to reduce insect pests in apple trees, and introduced possible ways to mitigate accumulation of insecticides in nectar and pollen.
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Title: Legitimacy of criminal justice organizations and democratic structures in countries of Africa : a comparison of 33 nations
Creator: Gillespie, Nolan Thomas
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The aim of this research is to examine perceived legitimacy in criminal justice organizations in less advanced democracies, specifically those that are considered flawed, hybrid, or authoritarian. More specifically the study examines how procedural fairness, corruption, social capital, and degrees of democracy effect trust in police and courts among African countries that differ significantly on various democracy metrics with data drawn from 33 African nations. The inquiry attempts to...
Show more"The aim of this research is to examine perceived legitimacy in criminal justice organizations in less advanced democracies, specifically those that are considered flawed, hybrid, or authoritarian. More specifically the study examines how procedural fairness, corruption, social capital, and degrees of democracy effect trust in police and courts among African countries that differ significantly on various democracy metrics with data drawn from 33 African nations. The inquiry attempts to reconcile the implications of democratic society with perceptions of criminal justice organizations. Findings and implications are discussed." -- Abstract.
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Title: The effects of doping and processing on the thermoelectric properties of platinum diantimonide based materials for cryogenic Peltier cooling applications
Creator: Waldrop, Spencer Laine
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The study of thermoelectrics is nearly two centuries old. In that time a large number of applicationshave been discovered for these materials which are capable of transforming thermalenergy into electricity or using electrical work to create a thermal gradient. Current use ofthermoelectric materials is in very niche applications with contemporary focus being upontheir capability to recover waste heat. A relatively undeveloped region for thermoelectricapplication is focused upon Peltier...
Show moreThe study of thermoelectrics is nearly two centuries old. In that time a large number of applicationshave been discovered for these materials which are capable of transforming thermalenergy into electricity or using electrical work to create a thermal gradient. Current use ofthermoelectric materials is in very niche applications with contemporary focus being upontheir capability to recover waste heat. A relatively undeveloped region for thermoelectricapplication is focused upon Peltier cooling at low temperatures. Materials based on bismuthtelluride semiconductors have been the gold standard for close to room temperature applicationsfor over sixty years. For applications below room temperature, semiconductors basedon bismuth antimony reign supreme with few other possible materials.The cause of this diculty in developing new, higher performing materials is due tothe interplay of the thermoelectric properties of these materials. The Seebeck coecient,which characterizes the phenomenon of the conversion of heat to electricity, the electricalconductivity, and the thermal conductivity are all interconnected properties of a materialwhich must be optimized to generate a high performance thermoelectric material. While forabove room temperature applications many advancements have been made in the creationof highly ecient thermoelectric materials, the below room temperature regime has beenstymied by ill-suited properties, low operating temperatures, and a lack of research.The focus of this work has been to investigate and optimize the thermoelectric propertiesof platinum diantimonide, PtSb2, a nearly zero gap semiconductor. The electronic propertiesof PtSb2 are very favorable for cryogenic Peltier applications, as it exhibits good conductivityand large Seebeck coecient below 200 K. It is shown that both n- and p-type dopingmay be applied to this compound to further improve its electronic properties. Throughboth solid solution formation and processing techniques, the thermal conductivity may bereduced in order to increase the thermoelectric gure of merit. Further reduction in thermalconductivity using other novel approaches is identied as an area of promising future research.Continued development of this material has the potential to generate a suitable replacementfor some low temperature applications, but will certainly further scientic knowledge andunderstanding of the optimization of thermoelectric materials in this temperature regime.
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Title: Electromagnetic transition strengths studied with Doppler-shift techniques across the contours of the valley of stability
Creator: Loelius, Charles Robert
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The electromagnetic transition strengths between bound states in nuclei provide insight into nuclear structure. On one hand, from a single particle perspective the electromagnetic excitation and de-excitation of nuclei quantify the overlaps of nuclear wavefunctions, probing the internal configuration. On the other hand, in a collective model, the shape and dynamics of the nucleus are reflected in the electromagnetic transition strengths. For example, electric quadrupole transitions are...
Show moreThe electromagnetic transition strengths between bound states in nuclei provide insight into nuclear structure. On one hand, from a single particle perspective the electromagnetic excitation and de-excitation of nuclei quantify the overlaps of nuclear wavefunctions, probing the internal configuration. On the other hand, in a collective model, the shape and dynamics of the nucleus are reflected in the electromagnetic transition strengths. For example, electric quadrupole transitions are sensitive to the deformation of a nucleus and distinguish between various pictures of collectivity, such as rotors and vibrators. In this work, electromagnetic transition strengths are studied through lifetime and Coulomb-excitation measurements. Nuclei across the contours of the valley of stability are studied to investigate features of nuclear structure and how they change near and far from stability.The first experiment discussed in this work investigates the effect of the $N=Z=28$ shell closure on collectivity in $^{58}$Ni. $^{58}$Ni has 28 protons and 30 neutrons, and therefore is not expected to exhibit enhanced collectivity compared to its neutron rich neighbors. However, a previous measurement of the lifetime of the $4_1^+$ state indicates an enhanced $B(E2;4_1^+\rightarrow2_1^+)$ transition strength, suggesting unexpectedly large collectivity. The present work revisits the lifetime of the $4_1^+$ state with a more sensitive technique, namely a Recoil Distance Method measurement at the National Superconducting Cyclotron Laboratory. The GRETINA detector array was employed with the S800 Spectrograph to measure the $4_1^+$ state lifetime. The model independent $B(E2;4_1^+\rightarrow2_{1}^+)$ from the present work supports an unenhanced transition strength, as expected near the shell closure.The second experiment discussed in this work is a study of the electromagnetic transition states in $^{27}$Ne. $^{27}$Ne is a loosely-bound neutron rich nucleus although it does not exhibit a halo structure in its ground state. This work investigates the excited states of $^{27}$Ne that lie closer to the particle threshold for features associated with a halo structure. The lifetimes of the $1/2^+$ and $3/2^-$ states in $^{27}$Ne and the branching ratio of the $1/2^+$ state decaying into the $3/2^-$ excited state and $3/2^+_{gs}$ ground state are measured. These values are used to determine the $B(E1;3/2^-\rightarrow3/2^+_{gs})$ and $B(E1;1/2^+\rightarrow3/2^-)$ values. It was found that the $B(E1)$ connecting the $1/2^+$ state to the $3/2^-$ state is at least 50 times larger than that between the $3/2^-$ and $3/2^+_{gs}$ states, indicating an extended radial component in the $1/2^+$ state wavefunction. Lifetime measurements of excited states in $^{28}$Ne are also presented. A new setup for performing Coulomb-excitation measurements based on heavy ion inelastic scattering with two targets is presented and employed to measure the $B(E2;3/2^+_{gs}\rightarrow1/2^+)$ strength in $^{27}$Ne. The method is demonstrated through a reference measurement of the $B(E2;0_{gs}^+\rightarrow2_1^+)$ of $^{30}$Mg. Combined with the lifetime measurement, the $B(M1;1/2^+\rightarrow3/2_{gs}^+)$ transition strength is extracted. The measured value is unhindered, indicating that the $1/2^+$ excited state of $^{27}$Ne is not dominated by an $s$-wave component. The electromagnetic transition strengths in $^{27}$Ne therefore indicate that the $1/2^+$ excited state may exhibit behaviors characteristic of deformed halos.In summary, this study of electromagnetic strengths demonstrates the features of nuclei in the valley of stability, and explores new aspects of nuclear structure that arise toward the edges of stability. Concurrently, Doppler-shift methods are shown to be powerful tools for investigating the structure of nuclei across the nuclear landscape.
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Title: Immigrant representation : a content analysis of media narratives of immigrants in U.K. and U.S. publications
Creator: Airgood, Bryce
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Immigration crises are not just indicative of the issues in countries that people are leaving. They represent major humanitarian crises that reflect the fears and beliefs of destination countries that include the United States, as well as the United Kingdom. The news media in both the United States and United Kingdom cover immigrants and their issues in different ways, depending on the new host country's political ideals. This research uses framing theory to analyze primary sources of the U.S...
Show moreImmigration crises are not just indicative of the issues in countries that people are leaving. They represent major humanitarian crises that reflect the fears and beliefs of destination countries that include the United States, as well as the United Kingdom. The news media in both the United States and United Kingdom cover immigrants and their issues in different ways, depending on the new host country's political ideals. This research uses framing theory to analyze primary sources of the U.S. publications The New York Times, The Washington Post and The Wall Street Journal, as well as the U.K. publications The Guardian, The Daily Telegraph and i. A qualitative content analysis of these publications revealed how immigrants are represented. It was discovered that in U.K. publications, immigrants were more likely to be represented in "politics," "immigrants as victims," or "immigrant support" frames. In U.S. publications, the articles were more likely to represent immigrants in "source of conflict," "immigration as a threat," and "immigration control" frames. This study indicates that the country of origin and that country's citizens' political ideals can affect immigrant representation in the media. -- Abstract.
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Title: Integrating a cereal rye cover crop and soybean row width with herbicides to manage Palmer amaranth in Michigan
Creator: Rogers, Kelsey Marie
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Glyphosate-resistant Palmer amaranth (Amaranthus palmeri S. Wats.) is an emerging concern for Michigan farmers. Integrating the use of cultural practices such as cover crops and narrow soybean row width may improve the control of herbicide-resistant Palmer amaranth in Michigan. In 2015 and 2016, field experiments investigated the effects of a cereal rye cover crop, including termination method, and soybean row width as cultural practices to improve Palmer amaranth control with herbicides....
Show more"Glyphosate-resistant Palmer amaranth (Amaranthus palmeri S. Wats.) is an emerging concern for Michigan farmers. Integrating the use of cultural practices such as cover crops and narrow soybean row width may improve the control of herbicide-resistant Palmer amaranth in Michigan. In 2015 and 2016, field experiments investigated the effects of a cereal rye cover crop, including termination method, and soybean row width as cultural practices to improve Palmer amaranth control with herbicides. Additional pot experiments were conducted to evaluate the effects of cereal rye stage, biomass, and termination method on Palmer amaranth emergence. Cereal rye biomass was greater in 2016 compared with 2015 due to the greater accumulation of growing degree days prior to cereal rye termination. Winter annual weeds were suppressed by more than 75% with cereal rye. However, overall Palmer amaranth emergence and control was not effected by cereal rye. In outdoor pot experiments, cereal rye suppression of Palmer amaranth emergence varied by year with the most consistent suppression with the later stage (Feekes 10.1 or later) cereal rye. In greenhouse pot experiments, total Palmer amaranth emergence was only reduced by cereal rye terminated by cutting compared with chemical termination. Planting soybean in narrow rows reduced the emergence period of Palmer amaranth in both years. Palmer amaranth was effectively controlled by both herbicide management strategies in 2015, while only the high management strategy provided season-long control in 2016. Utilizing an intensive herbicide management program and planting soybean in narrow rows provided the greatest impact on Palmer amaranth management in Michigan soybean production."--Page ii.
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Title: Salmonella typhimurium LT2 transfer and redistribution on baby spinach and cilantro during pilot-scale processing
Creator: Smolinski, Haley
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Several recent outbreaks traced to baby spinach and cilantro have been hypothesized to involve cross-contamination during washing and processing. Consequently, this study aimed to assess the redistribution of Salmonella Typhimurium LT2 during pilot-scale production of fresh-cut baby spinach and cilantro. Four inoculated:uninoculated product weight ratios (0.5:100, 1:100, 5:100, and 10:100) and three different inoculation levels (103, 101, and 10-1 CFU/g) were used with spot-inoculated red...
Show moreSeveral recent outbreaks traced to baby spinach and cilantro have been hypothesized to involve cross-contamination during washing and processing. Consequently, this study aimed to assess the redistribution of Salmonella Typhimurium LT2 during pilot-scale production of fresh-cut baby spinach and cilantro. Four inoculated:uninoculated product weight ratios (0.5:100, 1:100, 5:100, and 10:100) and three different inoculation levels (103, 101, and 10-1 CFU/g) were used with spot-inoculated red leaf lettuce serving as a colored surrogate for baby spinach and cilantro washing. Sanitizer-free wash water was used for all trials and a chlorine-based sanitizer was used at 60 ppm available chlorine only for the highest inoculation level (103 CFU/g) and the three highest weight ratios (1:100, 5:100, and 10:100). Overall, initial inoculation level had a greater impact on the amount of Salmonella-positive samples than the weight ratios examined for both commodities. The number of positive samples concurrently decreased as the initial inoculation level of the surrogate decreased. Within each inoculation level, no significant differences (P > 0.05) were found among the four product ratios. This is the first study to assess the spread of Salmonella from incoming product to baby spinach and cilantro during processing. These results will provide important data for microbial risk assessments associated with leafy greens.
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Title: Dreams of a soccer city : politics, consumption, and urban transformation in 20th century Buenos Aires
Creator: Galarza, Alex Gabriel
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This dissertation examines the Ciudad Deportiva of Club Atlético Boca Juniors, a massive stadium, sports complex, and leisure site that aimed to redevelop the city’s dilapidated riverfront in the 1960s. The directors of Boca Juniors drew state and municipal support for the Ciudad Deportiva by appealing to developmentalist ideals that prioritized public-private collaborations, consumption, and leisure space for middle class families. As Argentina’s most popular soccer club, hundreds of...
Show moreThis dissertation examines the Ciudad Deportiva of Club Atlético Boca Juniors, a massive stadium, sports complex, and leisure site that aimed to redevelop the city’s dilapidated riverfront in the 1960s. The directors of Boca Juniors drew state and municipal support for the Ciudad Deportiva by appealing to developmentalist ideals that prioritized public-private collaborations, consumption, and leisure space for middle class families. As Argentina’s most popular soccer club, hundreds of thousands of fans and supporters also invested in the project’s fundraising campaign with the belief that Boca’s stadium and facilities would contribute to the city’s modernization and symbolize national progress. Multiple democratic and military governments aided Boca’s efforts throughout a turbulent political and economic period in Argentina’s history, a signal that this kind of mass consumption and family leisure were key concerns for successive, yet divergent, political projects. The club completed most of the original planned facilities by 1970 including various sports fields, an amusement park, an aquarium, a concert pavilion, Argentina’s first drive-in movie theatre, and a social headquarters with a pool and restaurant. However, political infighting at the club, a withdrawal of public and private support, and national economic crises all contributed to Boca’s failure to construct the stadium in time for the 1978 FIFA World Cup. The municipality seized the Ciudad Deportiva in 1979 but over the next thirteen years Boca’s directors were able to regain control of the property and eventually sell it for 22 million dollars. Drawing on newspapers, sports magazines, club documents, and state sources, as well as over twenty oral histories, this dissertation makes two principal arguments. First, that soccer clubs played significant roles in shaping conceptions of neighborhood identity, gender, and class in 20th century Buenos Aires. These institutions did so in tension with their legal status as non-profit civic associations providing services to a membership base while also functioning as producers of the commercialized spectacle of professional soccer. Second, the successes and failures of the Ciudad Deportiva offer a unique perspective through which to consider the very real dreams of development that animated politics in the post-Peronist decades in Argentina. Scholars tend to focus on political polarization and instability, often obscuring the importance of notions about national and urban development embodied in the Ciudad Deportiva.
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Title: Newspaper coverage of the Flint Water Crisis : an empirical analysis to support a new model for latent environmental disasters
Creator: Tunney, Carin
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The Flint Water Crisis was a catastrophic disaster that reflects a previously, undefined pattern within human caused, slow-onset environmental crises. This pattern includes awareness, activism, governmental denial, and early signs of a legitimate, environmental hazard. This research defines the pattern as the Human Catalyst, Latent Disaster Model (HCLDM). The model is supported through review of mobilization frames, slow-onset environmental disasters, and incidents of environmental injustice....
Show moreThe Flint Water Crisis was a catastrophic disaster that reflects a previously, undefined pattern within human caused, slow-onset environmental crises. This pattern includes awareness, activism, governmental denial, and early signs of a legitimate, environmental hazard. This research defines the pattern as the Human Catalyst, Latent Disaster Model (HCLDM). The model is supported through review of mobilization frames, slow-onset environmental disasters, and incidents of environmental injustice. The model describes the predictable flow of latent disasters at various levels within society – the media, residents, government, and scientific community. This qualitative analysis of local, state, and national newspaper coverage of the Flint Water Crisis provides empirical support for the model. The analysis measures the concepts of significance, source bias, and environmental injustice through the lens of the normative theory of social responsibility. It found relationships between source-types and topics of environmental injustice consistent with a review of other incidents of latent environmental disasters. The findings help support the HCLDM as a predictive framework for study and offer a much-needed means of prediction for scholars, journalists, communities, and public health officials.
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Title: Use of water mist to reduce the risk of frost damage in tree fruits
Creator: Rijal, Ishara
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Climate variability and change have been major threats to global food security historically and will almost certainly continue to be threats in the future given the sensitivity of agricultural production systems to their surrounding environment. Recent changes in temperature and seasonality have significantly impacted commercial fruit production in the Great Lakes region. Michigan's sour cherry and apple production in 2012 was reduced by about 90% and 88%, respectively, compared to the...
Show moreClimate variability and change have been major threats to global food security historically and will almost certainly continue to be threats in the future given the sensitivity of agricultural production systems to their surrounding environment. Recent changes in temperature and seasonality have significantly impacted commercial fruit production in the Great Lakes region. Michigan's sour cherry and apple production in 2012 was reduced by about 90% and 88%, respectively, compared to the previous year's production due to a series of spring freeze events (USDA, 2013). The timing of the seasonal warm up in the spring and resulting onset of phenological development is a key factor in determining potential cold damage risk for overwintering perennial tree fruit crops, as the vulnerability of vegetation to freeze injury increases rapidly with the stage of development. Application of water prior to the onset of growth has been used in the past to delay early vegetative development of temperate tree fruit crops. Evaporative cooling associated with this approach effectively reduces plant tissue temperature, slowing the rate of growth and leaving it less vulnerable to freezing temperatures. There are several potential drawbacks, however, including consumption of large quantities of water that could increase nutrient leaching along with elevated risks of plant disease risk. This study examined the potential effectiveness of water applied as a spray mist via a new plant management technology, the solid set canopy delivery system (SSCD), to suppress tree fruit bud temperatures and delay the phenological development of the buds. There were two major portions: 1) A detailed collection of field-based phenological and physiological observations associated with the operation of a prototype SSCD cooling system and: 2) Development of a deterministic model of tree fruit bud temperature that was used to examine the potential of water-based cooling of buds in Michigan. The observational study aimed to identify the timing and discharge rate of mist applications on cherry and apple trees was carried out in a growth chamber and at five Michigan orchards (apple at St. Joseph, Charlotte, and Hillsdale, sweet cherry at SWMREC, and sour cherry at Traverse City,) during the 2014, 2015, and 2016 growing seasons with automated instrumentation to monitor and control the water mist flow rate based on environmental conditions. Water mist was applied to apple and cherry buds via the SSCD system after the end of endo-dormancy until king bloom in the non-misted buds based on ambient air temperature and relative humidity. Overall, in three years of the field study misting delayed bloom by 4-9 days in apple and 7- 11 days in cherry, all using substantially less water than that reported in earlier studies; 8.4 to 26 cm/ha in apple and 5.5 to 10.8 cm/ ha in sweet cherry. The deterministic heat transfer model of a tree fruit bud was developed with observational data from growth chamber, potted plant and field-based studies. The model was calibrated using growth chamber data and validated using potted plant and field data. In a model validation study, model simulated one-minute bud temperatures were generally found to be in good agreement with observed bud temperatures, with overall mean average differences of -0.5±0.30C (lab observations) and -0.3±0.15 0C (field observations), mean absolute differences less than 10C and R-square values of 0.80 or greater. The model was then run with ten years of hourly climate data at three locations in major fruit-producing regions of Michigan (2006-2015). Overall, the model estimated a delay in bloom of misted buds by more than a week compared to non-misted buds, which translates into a potential reduction in the frequency of damaging freeze events of 50-75 %, and decrease in freeze injury severity by 10-60 % in misted apple buds and 45-100% in misted cherry buds. Collectively, the results suggest that the spray mist technique has promise as a straightforward and effective indirect frost control strategy with relatively few environmental impacts.
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