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Title: SOCIAL MECHANISMS OF LEADERSHIP EMERGENCE : A COMPUTATIONAL EVALUATION OF LEADERSHIP NETWORK STRUCTURES
Creator: Griffin, Daniel Jacob
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Leadership emergence is a topic of immense interest in the organizational sciences. One promising recent development in the leadership literature focuses on the development and impact of informal leadership structures in a share leadership paradigm. Despite its theoretical importance, the network perspective of leadership emergence is still underdeveloped, largely due to the complexity of studying and theorizing about network-level phenomena. Using computational modeling techniques, I...
Show moreLeadership emergence is a topic of immense interest in the organizational sciences. One promising recent development in the leadership literature focuses on the development and impact of informal leadership structures in a share leadership paradigm. Despite its theoretical importance, the network perspective of leadership emergence is still underdeveloped, largely due to the complexity of studying and theorizing about network-level phenomena. Using computational modeling techniques, I evaluate the network-level implications of two existing theories that broadly represent social theories of leadership emergence. I derive formal representations for both foundational theories and expand on this theory to develop a synthesis theory describing how these two processes work in parallel. Results from simulated experiments indicate that group homogeneity is associated with vastly different leadership network structures depending on which theoretical process mechanisms are in play. This thesis contributes significantly to the literature by 1) advancing a network-based approach to leadership emergence research, 2) testing the implications of existing theory, 3) developing new theory, and 4) providing a strong foundation and tool kit for future leadership network emergence research.
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Title: The effect of kitchen-scale produce preparation techniques on the risk of listeriosis in cancer patients
Creator: Gomez, Carly
Date: 2020
Collection: Electronic Theses & Dissertations
Description: The foodborne pathogen L. monocytogenes generally infects immunocompromised individuals, but cancer patients in particular are infected more frequently, with higher morbidity and mortality. Because of the known risk of L. monocytogenes, and other pathogens, in produce, immunocompromised individuals are often placed on neutropenic diets that exclude fresh produce. Therefore, this study aimed to first evaluate several kitchen-scale treatments as potential interventions to reduce the population...
Show moreThe foodborne pathogen L. monocytogenes generally infects immunocompromised individuals, but cancer patients in particular are infected more frequently, with higher morbidity and mortality. Because of the known risk of L. monocytogenes, and other pathogens, in produce, immunocompromised individuals are often placed on neutropenic diets that exclude fresh produce. Therefore, this study aimed to first evaluate several kitchen-scale treatments as potential interventions to reduce the population of L. monocytogenes in prepared produce (apples, cucumbers, and celery), then develop a data-driven risk model for listeriosis in cancer patients who consume ready-to-eat (RTE) salads, as influenced by the kitchen-scale treatments. Surface blanching and surface blanching followed by peeling were the most effective treatments in both cucumbers (mean reductions of 5.1 and 5.9, respectively) and apples (mean reductions of 3.5 and 4.2 log cfu/g, respectively) (P < 0.05). All treatments lacked efficacy for celery, with reductions significantly less (P < 0.05) than in other products, likely due to considerable inoculum internalization. For refrigerated salads with no treatment, the median risk of invasive listeriosis over a period of one chemotherapy cycle was predicted to be at most 5.6 x 10-10. This decreased to 7.3 x 10-11 when salad components were surface blanched. Results from this study can be used to develop improved risk management strategies and risk communication materials for cancer patients and their caretakers.
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Title: Analysis of slip transfer in TI-5AL-2.5SN (WT. %) at two temperatures in comparison to pure aluminum
Creator: Edge, Chelsea M.
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Understanding the deformation mechanisms present near grain boundaries in polycrystalline hexagonal alloys will aid in improving modeling methods. Ti-5Al-2.5Sn samples were tensile tested at 296K and 728K, and slip behavior was assessed near grain boundaries. From the EBSD measurements of grain orientations, various metrics related to the slip systems, traces, residual Burgers vectors, and grain boundary misorientation were computed for boundaries showing evidence of slip transfer and...
Show moreUnderstanding the deformation mechanisms present near grain boundaries in polycrystalline hexagonal alloys will aid in improving modeling methods. Ti-5Al-2.5Sn samples were tensile tested at 296K and 728K, and slip behavior was assessed near grain boundaries. From the EBSD measurements of grain orientations, various metrics related to the slip systems, traces, residual Burgers vectors, and grain boundary misorientation were computed for boundaries showing evidence of slip transfer and boundaries showing no evidence of slip transfer. This work is compared to a similar study of an Aluminum oligo-crystal to aid in understanding the differences in slip behavior near grain boundaries in HCP and FCC crystal structures. Slip transfer in Ti525 was generally observed in less geometrically compatible conditions than Al, and slip transfer occurs at high misorientation angles in Ti-5Al-2.5Sn much more frequently than in Al.
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Title: A SURFACE WATER δ18O BASELINE FOR ARCHAEOLOGICAL STUDIES OF SEASONALITY AND MOBILITY IN THE MAJES VALLEY AND PUCUNCHO BASIN OF SOUTHERN PERU
Creator: Milton, Emily Beatrice Peterson
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Oxygen isotopes in archaeological human and animal teeth provide a potential means to study past migration. In this thesis I evaluate oxygen isotopes as a way to measure highland site occupation seasonality and human movement between elevation zones in the Central Andes. I focus on two questions: 1) Do surface water δ18O values vary predictably with altitude? and 2) Do surface water δ18O values reliably record the wet and dry season? Using water samples collected from the Majes Valley and...
Show moreOxygen isotopes in archaeological human and animal teeth provide a potential means to study past migration. In this thesis I evaluate oxygen isotopes as a way to measure highland site occupation seasonality and human movement between elevation zones in the Central Andes. I focus on two questions: 1) Do surface water δ18O values vary predictably with altitude? and 2) Do surface water δ18O values reliably record the wet and dry season? Using water samples collected from the Majes Valley and Pucuncho Basin of southern Peru, I establish the seasonal and spatial distribution of δ18O. The final dataset represents 98 water samples collected during wet and dry seasons between 2018-2019, from elevations 36 to 4938 meters above sea level. Surface water δ18O and δD values in the study area are consistent with regional and global meteoric waters. Individual water bodies demonstrate relatively higher δ18O values during the dry season and lower δ18O values in the wet season, matching predictions. Lowland and highland surface waters demonstrate overlapping ranges of δ18O, making it impossible to predict the values of surface waters based on elevation alone. Rather, local δ18O appears to reflect evaporative processes influenced by stream order, catchment size, and the geographic position of a waterbody within the watershed. These data suggest oxygen isotopes are not independently suited to resolve questions of human mobility between elevation zones in the western Andes. Further testing is needed to understand the local seasonal and inter-zonal isotopic ecology.
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Title: A dimensional comparison of selected Japanese gardens, classical Chinese gardens and modern Chinese gardens
Creator: Qu, Yige
Date: 2019
Collection: Electronic Theses & Dissertations
Description: The relationships between Japanese gardens and Chinese gardens have been studied and discussed for a long time. This study focuses on the topic by a quantitative method. A cluster analysis is conducted to define the similarities and differences between these two kinds of gardens. The distinctive varieties in the result shows the elements that presents the relationships most distinctively. For this study, the data is collected in both Chinese gardens and Japanese gardens in order to show more...
Show moreThe relationships between Japanese gardens and Chinese gardens have been studied and discussed for a long time. This study focuses on the topic by a quantitative method. A cluster analysis is conducted to define the similarities and differences between these two kinds of gardens. The distinctive varieties in the result shows the elements that presents the relationships most distinctively. For this study, the data is collected in both Chinese gardens and Japanese gardens in order to show more persuasive results illustrating the relationships between these gardens. Principal component analysis is used to analyze the data, and to show intuitional visual results by graphs. The statistic software output shows a set of principal components. First three principal components contain roughly 59% of the variance. The design elements that distinctively effect the relationship are also indicated in the results, which lead further interpretation about the topic. The scatter graph shows distinct differences between Chinese gardens and Japanese gardens. Major elements divided Chinese gardens and Japanese gardens, traditional gardens and modern gardens, and Japanese gardens. This research can be used by garden designers and researchers to gain a insight concerning of the similarities and differences between Japanese gardens and Chinese gardens.
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Title: CD2 regulates pathogenesis of asthma induced by house dust mite extract
Creator: Hashem, Tanwir
Date: 2019
Collection: Electronic Theses & Dissertations
Description: The inflammatory immune response that is characteristic of allergic asthma is triggered by exposure to allergens such as house dust mice extract (HDME) and is driven by CD4+Th2 lymphocytes that secrete large quantities of Th2 cytokines including interleukin (IL)-4, IL-13, and IL-5. Surface expression of CD2 and its ligand CD58, is increased on the monocytes and eosinophils of asthma patients, which correlate with elevated serum IgE levels, suggesting that CD2 may contribute to allergic airway...
Show moreThe inflammatory immune response that is characteristic of allergic asthma is triggered by exposure to allergens such as house dust mice extract (HDME) and is driven by CD4+Th2 lymphocytes that secrete large quantities of Th2 cytokines including interleukin (IL)-4, IL-13, and IL-5. Surface expression of CD2 and its ligand CD58, is increased on the monocytes and eosinophils of asthma patients, which correlate with elevated serum IgE levels, suggesting that CD2 may contribute to allergic airway inflammation. Using a murine model of asthma, we observed that HDME-exposed Balb/c mice have increased airway hyper responsiveness (AHR), cellular infiltration, goblet cell hyperplasia, and elevated levels of Th2 cytokines in the lungs, as well as increased serum IgE levels as compared to the control mice. In contrast, AHR, and cellular infiltration were significantly reduced in HDME-exposed Cd2-/- mice. Interestingly, Il13 but not Il4 or Il5 gene expression in the lungs was significantly reduced in HDME-exposed Cd2-/- mice. Of note, the gene expression of polymeric mucins, Muc5b and Muc5ac were significantly reduced in the lungs of HDME-exposed Cd2-/- mice. Furthermore, gene expression of various protective micro RNAs were increased in the lungs of HDME-exposed Cd2-/- mice. Lastly, in a mouse model of neutrophilic asthma, Cd2-/- mice exhibit significantly reduced AHR and Il13 and Il17a gene expression. Given the established role of IL-13 in promoting goblet cell hyperplasia and mucus production during allergic asthma, and various micro RNAs regulating different aspects of asthma symptoms, our studies reveal a unique role for CD2 in both Th2-high and Th2-low asthma.
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Title: Informal settlements and the geography of vulnerability - a spatial case study of Hidalgo County, Texas
Creator: Huang, Huiqing (Graduate of Michigan State University)
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "More than 2,000 colonias and more than 800 model subdivisions have been developed in unincorporated areas across the state of Texas. Since the 1980s, a substantial body of research has documented the poor housing conditions and inadequate infrastructure in these informal settlements in the United States. However, very little research has focused on the geographic vulnerability, such as exposure to environmental risks and the lack of access to amenities. This study adopts two Geographic...
Show more"More than 2,000 colonias and more than 800 model subdivisions have been developed in unincorporated areas across the state of Texas. Since the 1980s, a substantial body of research has documented the poor housing conditions and inadequate infrastructure in these informal settlements in the United States. However, very little research has focused on the geographic vulnerability, such as exposure to environmental risks and the lack of access to amenities. This study adopts two Geographic Information System (GIS) methods (overlay analysis and proximity analysis) to investigate the vulnerability of informal settlements in Hidalgo County, Texas. This research finds that informal settlements experience more spatial vulnerability than formal neighborhoods as they are further away from the urban center, the job center, and other critical amenities. However, the prevalence of property crime in informal settlements is significantly lower. Within the informal settlements, colonias are still in need of basic infrastructures. Besides, this study finds that state-designated colonias are less vulnerable than newer model subdivisions that have developed largely without acknowledgment by the state.These findings suggest the need for state and local governments 1) to make more targeted investments to provide water and wastewater service; 2) to develop public transportation system; 3) to reduce vulnerability by expanding access to amenities or services and 4) to partner with private entities and communities themselves to address the needs in informal settlements."--Page ii.
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Title: Foundations for genetic engineering in the shikimate pathway of Bacillus methanolicus MGA3
Creator: Gruenberg, Megan
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Numerous widely-used chemicals, such as adipic acid, are produced from hydrocarbons that come from petroleum. Consumption of petroleum contributes to global climate change and ocean acidification, which has created a great need for the development of petroleum independent chemical synthesis methods. Recently, considerable interest has turned toward using methanol as a feedstock for chemical synthesis because of its abundance, ease of purification, and lack of ties to the food industry. Adipic...
Show moreNumerous widely-used chemicals, such as adipic acid, are produced from hydrocarbons that come from petroleum. Consumption of petroleum contributes to global climate change and ocean acidification, which has created a great need for the development of petroleum independent chemical synthesis methods. Recently, considerable interest has turned toward using methanol as a feedstock for chemical synthesis because of its abundance, ease of purification, and lack of ties to the food industry. Adipic acid precursor cis,cis-muconic acid has been biosynthesized in a variety of production hosts, but it has not been biosynthesized using a methanol feedstock. In this work, groundwork was laid for genetically engineering the thermophilic, methylotrophic bacterium Bacillus methanolicus MGA3 for cis,cis-muconic acid production from methanol via the shikimate pathway. The first enzyme in the shikimate pathway is 3-deoxy-D-arabinoheptulosonate-7-phosphate (DAHP) synthase. This enzyme has been shown to play an important role in the regulation of carbon flow into the pathway. B. methanolicus MGA3 DAHP synthase isozymes AroG1 and AroG2 were characterized. Both isozymes were found to be Type Iβ DAHP synthases, with AroG1 being unregulated at the protein level and AroG2 being allosterically regulated by the aromatic amino acid precursors chorismate and prephenate. Additionally, methods for storing and screening B. methanolicus shikimate pathway mutants were developed. The established storage method allows B. methanolicus to be mutagenized in large batches and subsequently stored as spores. Agar plate growth medium recipes were developed for germinating B. methanolicus spores and phenotypic screening of mutants.
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Title: Cultural relativity in conflict resolution : cross-cultural and intra-cultural differences
Creator: Somaraju, Ajay
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Although there is an extensive literature on the relationship between cultural values and conflict resolution preferences, there is less research on the role of cultural worldviews in predicting these values, and how cultural values interplay with ethical positions when resolving conflict. The purpose of this study was to examine the cross-cultural pattern of relationships among idealistic and relativistic thinking, cultural values, and conflict resolution preferences. Specifically, the...
Show moreAlthough there is an extensive literature on the relationship between cultural values and conflict resolution preferences, there is less research on the role of cultural worldviews in predicting these values, and how cultural values interplay with ethical positions when resolving conflict. The purpose of this study was to examine the cross-cultural pattern of relationships among idealistic and relativistic thinking, cultural values, and conflict resolution preferences. Specifically, the current study examined Aristotelian, Hindu, and Confucian cultural subgroups to identify cross-cultural and intra-cultural differences. Results suggested that individuals' ethical positions predicted their cultural values, which in turn predicted their conflict resolution preferences. Moreover, results suggested that there was differential prediction between individualist and relational (i.e., Aristotelian vs. Hindu and Confucian) subgroups and within relational subgroups (i.e., Hindu vs Confucian).
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Title: La lutte pour l'integration sociale de la femme dans les oeuvres de Mariama Ba
Creator: Wanda, Sylvie Lakaine
Date: 2020
Collection: Electronic Theses & Dissertations
Description: La lutte pour l'integration sociale de la femme etait au coeur des preoccupations d'une societe postcoloniale Senegalaise en pleine mutation. C'est ce qui a incite de nombreuses auteures a l'instar de Mariame Ba qui a travers ses ecrits a formule son combat dans la lutte pour la liberation de la femme. Cette domination masculine a l'egard de la femme s'est accentuee a travers la colonisation qui avait pour consequence de ravaler la femme au second plan en lui infligeant un complexe flagrant d...
Show moreLa lutte pour l'integration sociale de la femme etait au coeur des preoccupations d'une societe postcoloniale Senegalaise en pleine mutation. C'est ce qui a incite de nombreuses auteures a l'instar de Mariame Ba qui a travers ses ecrits a formule son combat dans la lutte pour la liberation de la femme. Cette domination masculine a l'egard de la femme s'est accentuee a travers la colonisation qui avait pour consequence de ravaler la femme au second plan en lui infligeant un complexe flagrant d'inferiorite. L'indignation de l'auteure s'est faite ressentie lorsqu'elle a pris position pour combattre toutes sortes de discrimination eprouvees par la femme, en leur donnant du courage, et en les invitant a prendre leur destin en main.C'est ainsi qu'a partir des annees 1980, son combat est porteur de fruit de nos jours lorsqu'on constate de maniere incontestable l'integration de la femme dans les affaires politiques, sociales, administratives avec surtout la consecration de leurs droits a travers de nombreux instruments juridiques.
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Title: Methods of distinguishing crosses between similar bean varieties
Creator: Lightfoot, Ceylon C.
Date: 1926
Collection: Electronic Theses & Dissertations

Title: Lake Michigan stakeholders' perceptions of coastal risk and motivations for coastal habitat stewardship
Creator: Whyte, Julia H.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Lake Michigan communities have already begun to feel the effects of climate change, and research suggests that these areas will experience many phenomena that will negatively impact the ecosystem and human livelihoods (GLISA, 2014). While agencies exist to generally guide coastal management, Michigan lacks institutions that establish regulations or requirements for managing the Great Lakes coastal region (Norton et al., 2018). As a result, Michigan's coastal communities have the...
Show moreLake Michigan communities have already begun to feel the effects of climate change, and research suggests that these areas will experience many phenomena that will negatively impact the ecosystem and human livelihoods (GLISA, 2014). While agencies exist to generally guide coastal management, Michigan lacks institutions that establish regulations or requirements for managing the Great Lakes coastal region (Norton et al., 2018). As a result, Michigan's coastal communities have the responsibility of preparing for an uncertain future under climate change. I compared risk perceptions between different resident groups, as well as between different communities, varying by county, size, and presence of a previous coastal resiliency program. I used a four-wave tailored design for data collection (Dillman, 2009) in six Michigan communities along Lake Michigan from December 2018 to April 2019. I found communities with resiliency programs are less concerned about coastal risk than other communities and lake residents are more concerned about coastal risk than municipal officials. I also found that previous experience with environmental risk and gender are predictors of concern about coastal risk. I suggest that future outreach materials focus on lake residents and that community-engaged work to create more robust coastal resilience plans are beneficial to mitigating risk perceptions. The results from this research can also be used to inform future planning and zoning policies, as well as other coastal resilience policies.
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Title: Bridging gaps in information : strategies for improving natural resource management in a changing climate
Creator: Tracy, Erin
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "The Great Lakes region has an abundance of natural resources that are ecologically and socioeconomically valuable yet threatened by changing climate. To effectively address impacts of climate change within the Great Lakes region will require managers to mitigate the causes of climate change as well as adapt to current threats and to future changes in both social and ecological systems. This thesis addresses those needs by providing natural resource managers with strategies to increase...
Show more"The Great Lakes region has an abundance of natural resources that are ecologically and socioeconomically valuable yet threatened by changing climate. To effectively address impacts of climate change within the Great Lakes region will require managers to mitigate the causes of climate change as well as adapt to current threats and to future changes in both social and ecological systems. This thesis addresses those needs by providing natural resource managers with strategies to increase support for climate change mitigation policies and by providing them with information on how social and ecological systems may change with changing climate so that they can develop and apply novel management strategies. Results from Chapter 1 show that while Michigan conservation organizations vary in their current engagement with climate change issues and in their willingness to increase engagement with their membership depending on perceived barriers, every organization expressed interest in receiving more information on how climate change will affect the state's fish and wildlife populations. In Chapter 2, we characterized how resilient Michigan river fish habitat may be to anticipated changes in climate. Our results indicate that while cumulative resilience is generally higher in the Upper Peninsula and in the Northern Lower Peninsula, resilient streams are also found in the Southern Lower Peninsula, suggesting that managers have opportunities in every part of the state for protecting and/or improving stream resiliency to changing climate. Collectively, outcomes of this research offer managers new information and strategies for mitigating and adapting to climate change, ultimately facilitating the sustainable management of natural resources in a changing climate."--Page ii.
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Title: A geometry based approach towards improving the structural integrity of single-walled ti6al4v alloy features fabricated using laser directed energy deposition additive manufacturing
Creator: Thakkar, Darshan
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Presence of sharp turns in the deposition tool-path for Additive Manufacturing (AM) introduces heterogeneity in built-part thereby affecting structural integrity. Slower deposition speeds around turn points or corner leads to defects such as increased wall thickness, porosity, lack of fusion voids, and cracks. Such defects can be minimized by either by optimizing processing parameters or through geometry optimization. Optimizing processing parameters requires extensive and expensive set of...
Show morePresence of sharp turns in the deposition tool-path for Additive Manufacturing (AM) introduces heterogeneity in built-part thereby affecting structural integrity. Slower deposition speeds around turn points or corner leads to defects such as increased wall thickness, porosity, lack of fusion voids, and cracks. Such defects can be minimized by either by optimizing processing parameters or through geometry optimization. Optimizing processing parameters requires extensive and expensive set of experiments. Furthermore, it is challenging to accurately model the process and have closed loop controls because of the impracticality to include all process parameters. This work focuses on optimizing the geometry instead of process parameters to fabricate components with minimum defects. In this work, single walled cubical Ti6Al4V shells with sharp and rounded corners were fabricated using laser Directed Energy Deposition (DED). Cross sectional and build plane coupons were extracted from each sample for microstructure and defect analysis. Results show that inclusion of rounded corners leads to consistent deposition speeds. Defect density measurements, using optical microscope, show reduction of defects from 6.8 ± 0.35% to a virtually defect-free structure for samples with rounded corners. Results indicate that consistent deposition speed around rounded corners improved homogeneity in the resulting microstructure.
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Title: A meditation on loss within games
Creator: Tokarski, Justin C.
Date: 2016
Collection: Electronic Theses & Dissertations
Description: "Failure is something which we are all familiar with, but when we look at games and the rules which govern them failure takes on a different form. This kind of failure, unique to games, is what I term Loss. To be truly unique to games, Loss must be the result of gamic actions taken by the player, must be constrained by the limitations of the game, and must represent a unique occurrence or state within the game. Taking these constraints into account I propose the following as a definition of...
Show more"Failure is something which we are all familiar with, but when we look at games and the rules which govern them failure takes on a different form. This kind of failure, unique to games, is what I term Loss. To be truly unique to games, Loss must be the result of gamic actions taken by the player, must be constrained by the limitations of the game, and must represent a unique occurrence or state within the game. Taking these constraints into account I propose the following as a definition of Loss. Loss is a player state in a game, entered into when a 'Loss Condition' has been met by the direct actions of the player, wherein something valued by the player within the game is removed. This definition, upon inspection, leads to several different and unique aspects, or dimension, of Loss which provide useful tools for understanding, analyzing, and creating Loss within games. The Digital Dimension of Loss consists of the binary triggers, Loss Conditionals, which lead the game to enter a State of Loss. The Design Dimension of Loss is the method of translating Loss Conditionals into unique game events understandable to the player. The Value Dimension of Loss consists of the gamic measures of effort that are taken away from the player by Loss. Finally, the Experience Dimension of Loss concerns the subjective effects of Loss on the player and methods for predicting what these effects will be. Together, this definition and the 4 aspects of Loss provide us new tools for understanding Loss as unique to games and distinct from failure in non-game contexts."--Page ii.
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Title: THE VALUE OF HABITAT DATA FOR CONSERVING STREAMS WITH CHANGING CLIMATE : PROMOTING GREATER USE FOR MORE EFFECTIVE MANAGEMENT
Creator: Betances, Samantha J.
Date: 2021
Collection: Electronic Theses & Dissertations
Description: North America’s rivers and streams support a diversity of fish species that provide significant ecological, socioeconomic, cultural, and spiritual benefits, and the quality and quantity of habitat in streams directly supports fish diversity. Because rivers are products of the landscapes they drain, features of the landscape like land use, geology, and climate control habitat. Based on these relationships, it stands that anticipated changes in climate will lead to changes in stream fishes...
Show moreNorth America’s rivers and streams support a diversity of fish species that provide significant ecological, socioeconomic, cultural, and spiritual benefits, and the quality and quantity of habitat in streams directly supports fish diversity. Because rivers are products of the landscapes they drain, features of the landscape like land use, geology, and climate control habitat. Based on these relationships, it stands that anticipated changes in climate will lead to changes in stream fishes through changes in habitat. While natural resource management agencies collect habitat data to help conserve streams into the future, stream habitat data are not always used as intended, in part because some managers may have an incomplete understanding of interactions between rivers and the landscapes they drain. To fully address the impacts of climate change on stream fishes, managers must better understand how climate affects stream habitat and incorporate these concepts into management decision-making processes. This thesis addresses that need. In Chapter 1, we identify ways to increase use of stream habitat data by natural resource management agencies to better conserve fishes from current and future stressors. In Chapter 2, we investigate influences of multiple landscape factors on physical stream habitat, including climate factors. Collectively, outcomes of this research offer managers information and strategies for using stream habitat data to conserve stream habitats and the fishes they support with changing climate.
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Title: Thermal Characterization and Crystal Growth of the Germanium Telluride-Tin Telluride System
Creator: Levental, Gill
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Thermoelectric materials, which can create an electrical current from a temperature gradient within the material, are an important means of generating electrical power in very remote and harsh environments. However, their deployment in terrestrial environments has been limited, due to two primary factors: the high cost of thermoelectric materials and their low energy conversion efficiency- too low for economic use in almost all applications. One method by which thermoelectric material energy...
Show moreThermoelectric materials, which can create an electrical current from a temperature gradient within the material, are an important means of generating electrical power in very remote and harsh environments. However, their deployment in terrestrial environments has been limited, due to two primary factors: the high cost of thermoelectric materials and their low energy conversion efficiency- too low for economic use in almost all applications. One method by which thermoelectric material energy conversion efficiency may be increased is by reducing material lattice thermal conductivity, or a material’s ability to conduct heat through the vibrations of its crystalline atomic lattice, which are called phonons. In support of that objective, this work presents a characterization of fundamental material properties that influence the lattice thermal conductivity of the germanium telluride-tin telluride (Ge1-xSnxTe) system, a promising thermoelectric material. The properties characterized include composition-dependent coefficients of thermal expansion, speeds of sound within the material, and elastic moduli. These were characterized using high-temperature X-ray diffraction, resonant ultrasound spectroscopy, and high-pressure X-ray diffraction, respectively. This work also presents an account of the synthesis of bulk single-crystal ingots of several compositions within the Ge1-xSnxTe system, which will be used for an in-depth investigation of Ge1-xSnxTe phonon characteristics by collaborators using inelastic neutron scattering.
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Title: CHARACTERIZING THE SOCIAL GAP IN UTILITY-SCALE SOLAR ENERGY
Creator: Crawford, Jessica Alex
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Many consider utility-scale photovoltaic solar power to be an essential component of decarbonizing the United States power sector and mitigating climate change. This technology is well accepted by the public in general surveys, yet often faces local resistance during project siting. This phenomenon is known as the “social gap.” Using social gap theory from the wind energy literature as a foundation, this study examines the causes of and offers recommendations for addressing the solar social...
Show moreMany consider utility-scale photovoltaic solar power to be an essential component of decarbonizing the United States power sector and mitigating climate change. This technology is well accepted by the public in general surveys, yet often faces local resistance during project siting. This phenomenon is known as the “social gap.” Using social gap theory from the wind energy literature as a foundation, this study examines the causes of and offers recommendations for addressing the solar social gap in Michigan. The study relied on 33 semi-structured interviews with citizens, government officials, and developers across four Michigan communities, each facing a prospective utility-scale solar project. Through thematic analysis, I show that the solar social gap can be attributed to both a vocal minority that dominated community sentiment and project proposals that failed to meet the community’s standards for acceptable development. The gap was exacerbated by the presence of organized opposition groups as well as decision-makers relying on ineffective public processes to engage citizens. This research makes it clear that government officials and developers need to adopt practices that enhance community representation, process transparency, and decision-influence. Though decision-making strategies are not the only factor that affects community acceptance, implementing improved procedures could help close the solar social gap.
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Title: Co-contractile differences during adaptation to abrupt and gradual dynamic perturbations
Creator: Ptashnik, David W.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "Adaptation to a novel motor task has been shown to be facilitated through co-contraction as well as exposure to a gradual, rather than an abrupt, dynamic perturbation. In this study, participants performed center out reaching movements in a velocity dependent force field. One group was exposed to a perturbing force of 20 N·m-1·s, another group was exposed to 5 N·m-1·s -step increments of perturbing force up to a total force of 20 N·m-1·s. Adaptation measured by randomly interspersed channel...
Show more"Adaptation to a novel motor task has been shown to be facilitated through co-contraction as well as exposure to a gradual, rather than an abrupt, dynamic perturbation. In this study, participants performed center out reaching movements in a velocity dependent force field. One group was exposed to a perturbing force of 20 N·m-1·s, another group was exposed to 5 N·m-1·s -step increments of perturbing force up to a total force of 20 N·m-1·s. Adaptation measured by randomly interspersed channel trials was found to be better in the group exposed to the gradually increasing perturbation. However, no significant differences were observed in levels of muscle activity during the exposure period. These results suggest that despite both co-contraction, and exposure to a gradual perturbation facilitating dynamic motor adaptation, these two mechanisms are independent of one another."--Page ii.
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Title: EXPLORING THE IMPACT OF BIOGAS QUANTITY AND QUALITY IN DIFFERENT DIGESTER TYPES WITH VARIATIONS IN TEMPERATURE
Creator: Barrios Arosemena, Maria Ines
Date: 2021
Collection: Electronic Theses & Dissertations
Description: The energy sector in the U.S. has been pushing for policies such as the Renewable Portfolio Standard (RPS) to mitigate the impacts of GHG emissions. Biogas from anaerobic digesters is a viable form of renewable energy, due to its CH4 composition, it can be used as a replacement for power and heat generation or upgraded and sold as biomethane. This study analyzed the effects of temperature in biogas quality and quantity of dairy cow manure in order to compare two main systems, a CSTR and a...
Show moreThe energy sector in the U.S. has been pushing for policies such as the Renewable Portfolio Standard (RPS) to mitigate the impacts of GHG emissions. Biogas from anaerobic digesters is a viable form of renewable energy, due to its CH4 composition, it can be used as a replacement for power and heat generation or upgraded and sold as biomethane. This study analyzed the effects of temperature in biogas quality and quantity of dairy cow manure in order to compare two main systems, a CSTR and a covered lagoon. A biochemical methane potential (BMP) test was performed to determine material biodegradability of dairy cow manure with respect to temperature. The results show that all samples are anaerobically biodegradable with samples yielding 86, 168, 440, 475 and 448 L biogas per kg initial VS for 15°C, non-mixed; 20°C, non-mixed; 30°C, non-mixed; 39°C, non-mixed; and 39°C, mixed, respectively. The BMP results demonstrated so significant difference between 30°C, non-mixed; 39°C, non-mixed; and 39°C, mixed, respectively. In addition, the effects of psychrophilic, unregulated, and mesophilic conditions were tested in small scale lab pilot digesters. Results show that mesophilic condition yielded the highest cumulative biogas production, while the psychrophilic and unregulated conditions presented higher methane yield. A life cycle analysis was performed to compare two popular anaerobic digestion systems, a CTSR and a covered lagoon, versus current manure management systems for dairy cow manure. The LCA revealed that both systems have less environmental burdens when compared to current waste management systems and a CSTR has less environmental burdens than a covered lagoon.
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