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Title: RURAL URBAN TERRITORIAL EFFECTS ON DAIRY FARMER INCLUSION IN MODERN MARKET CHANNELS : THE CASE OF COLOMBIA
Creator: Vargas Espinosa, Carolina María Teresa
Date: 2021
Collection: Electronic Theses & Dissertations
Description: This article analyzes how rural territories anchored by secondary/tertiary cities, denominated rural-urban territories (RUT) in the Southwest part of Colombia introduce spatial and territorial heterogeneity in the participation of farmers in restructured dairy value chains. We look at how different sized RUTs (with an urban center between 15k-400k inhabitants) affect farmer participation in modern market channels (such as large milk processors) as well as the transitional market channel ...
Show moreThis article analyzes how rural territories anchored by secondary/tertiary cities, denominated rural-urban territories (RUT) in the Southwest part of Colombia introduce spatial and territorial heterogeneity in the participation of farmers in restructured dairy value chains. We look at how different sized RUTs (with an urban center between 15k-400k inhabitants) affect farmer participation in modern market channels (such as large milk processors) as well as the transitional market channel (informal traders) on two different time periods (2008-2012 and 2013-2018). All while controlling for farmer micro characteristics, as well as the level of rural territorial development (degree of violence, density of infrastructure, and urban proximity) and geographical differences. Using a panel multinomial logit approach, we are able to find that urban size effects are positively significant in the probability of selling to both market channels. Even so, other territorial characteristics such as violence levels are key in modern market participation. Additionally, we are able to find that agglomeration effects are evident but vary by market channel. We see that higher agglomeration levels have a significant effect (negative effect) on the odds of selling to the transitional market but are less significant on the odds of selling to the modern channel. As fewer farmers have access to modern chains in developing countries, measures to make value chains more inclusive to remote farmers can benefit them and the performance of the dairy sector in Colombia.
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Title: A Phenomenological Inquiry of the Holistic Nonmedical Lived Training Experiences of End-of-Life Doulas (EOLDs)
Creator: Rozeboom, Angela M.
Date: 2021
Collection: Electronic Theses & Dissertations
Description: A new generation of aging United States (U.S.) citizens seems to be challenging cultural attitudes toward death and dying. The members of the senior baby-boom cohort are demanding more nonmedical end-of-life (EOL) home care, the right to experience a dignified and peaceful death, and the option of environmentally friendly burials. Subsequently, the field of end-of-life doulas (EOLDs) or death doula care is also emerging. As these practitioners raise awareness and claim to contribute to a...
Show moreA new generation of aging United States (U.S.) citizens seems to be challenging cultural attitudes toward death and dying. The members of the senior baby-boom cohort are demanding more nonmedical end-of-life (EOL) home care, the right to experience a dignified and peaceful death, and the option of environmentally friendly burials. Subsequently, the field of end-of-life doulas (EOLDs) or death doula care is also emerging. As these practitioners raise awareness and claim to contribute to a better quality of EOL care, they add a new dimension to the EOL field. The purpose of this qualitative phenomenological study was to understand the lived training experiences of prospective EOLDs as they sought to aid the dying and their grieving families. Individual interviews with seven trained EOLDs who completed a training program were analyzed. The results showed that those who attended the EOLD training felt strongly “called” to do EOL work. After confronting and accepting their fears and anxieties about their future dying and death experiences, they reported feeling empowered to come alongside EOL individuals and offer genuine comfort on their dying journey and postmortem care to the family.
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Title: A STUDY ON FLUID-STRUCTURE INTERACTION OF SWIMMING BEAM USING IMMERSED BOUNDARY- LATTICE BOLTZMANN METHOD
Creator: Rahman, Md Towhidur
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Fluid-structure interaction (FSI) study is of great importance to understand the hydrodynamic coupling of biological swimmers in surrounding environmental domain. Multiple numerical and experimental studies have taken place to capture the behavioral pattern from the environment, explore the physical phenomena and comprehension of dynamics to make contribution in real life applications. In this study, an immersed boundary-lattice Boltzmann method (IB-LBM) for fluid-structure interaction...
Show moreFluid-structure interaction (FSI) study is of great importance to understand the hydrodynamic coupling of biological swimmers in surrounding environmental domain. Multiple numerical and experimental studies have taken place to capture the behavioral pattern from the environment, explore the physical phenomena and comprehension of dynamics to make contribution in real life applications. In this study, an immersed boundary-lattice Boltzmann method (IB-LBM) for fluid-structure interaction problems is presented. The impact of solid structure on to the surrounding fluid domain is dealt with by immersed boundary method (IBM), where the structure is assumed to be immersed into surrounding fluid and the effect of the immersed boundary are considered by exertion of Lagrangian force onto the surrounding fluid grid points as body force. The flow dynamics is determined by solving discrete lattice Boltzmann equation of a single relaxation time model. The structural dynamics are solved by the finite difference method. For solving the structural dynamics, inextensibility condition was applied. A staggered grid is used in the Lagrangian coordinate system, where tension force is defined on the interfaces (half-grids) and other variables are defined on the nodes. Tension force is calculated at the intermediate steps and used as inextensibility constraint to obtain filament position at the next time step. In the present study, a detailed derivation and corresponding discretization is done for multiple free-swimming cases for a thin flexible filament. The thin flexible filament is actuated by imposing oscillatory heaving and pitching motion at the leading edge with prescribed control parameters. The flow physics of the system is investigated and pressure on the surfaces of the flexible filament is obtained. The results obtained in this study shows consistency with previous publications. The presented computational modelling may be used in future with multiple obstacles in the domain, to investigate the surface pressure variation of the swimming flexible filament and generated data sets may contribute to optimization of control mechanism of the swimmer.
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Title: Cover crops and cover crop residues regulate rates of soil microbial decomposition and plant available nitrogen
Creator: Egboluche, Nzube Prisca
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Changes in soil microbial community and activities can influence the nutrient cycling and its availability to plants. I conducted a one-year soil incubation study to: evaluate the effects of short- and long-term N additions on the soil microbial activities and how cover crop residue mixtures influence ecosystem functions. Two legume residues, Vicia villosa - hairy vetch (V) and Pisum sativum - field pea (P) with C:N ratio 12.8 and 10.5 respectively and two non-legume residues, Pennisetum...
Show moreChanges in soil microbial community and activities can influence the nutrient cycling and its availability to plants. I conducted a one-year soil incubation study to: evaluate the effects of short- and long-term N additions on the soil microbial activities and how cover crop residue mixtures influence ecosystem functions. Two legume residues, Vicia villosa - hairy vetch (V) and Pisum sativum - field pea (P) with C:N ratio 12.8 and 10.5 respectively and two non-legume residues, Pennisetum glaucum - pearl millet (M) and Lolium multiflorum - rye grass (R) with C:N ratio 37.8 and 14.3 respectively were used in this study. Soils amended with V and R had greater inorganic N compared to M and P residues while in soils with residue mixtures I observed non-additive synergistic (NAS) effect on inorganic N at the initial and final stage of the incubation period. Long-term N addition increased inorganic N but was apparent with short-term N fertilizer. Addition of both short- and long-term N increased [beta]-1,4,-glucosidase (BG), [beta]-D-1,4-cellobiohydrolase (CBH), phenol oxidase (PO), peroxidase (PER) and acid phosphatase (PHOS) with the exception of Leucine-aminopeptidase (LAP) and urease enzyme activities. There was non-additive antagonistic (NAA) effects on cellulase, total oxidase, [beta]-1,4,-N-acetyl glucosaminidase (NAG) and NAS effects on LAP, urease and PHOS enzyme activities. The addition of residues likely stimulated microbial growth, but the NAA effect of residue mixtures on C acquisition enzyme (cellulase and total oxidase) activities suggests development of C limitation.
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Title: Suitability of the RSP2pro software-defined radio for precompliance radiated emissions testing
Creator: Stevers, William, II
Date: 2020
Collection: Electronic Theses & Dissertations
Description: This thesis demonstrates the ability to use an existing software-defined radio for accurate RF measurements related to the precompliance testing of radiated emissions. The software-defined radio chosen for this work is the SDRplay Radio Spectrum Processor 2 Pro (RSP2pro). The RSP2pro was chosen because of its ability to provide absolute received power measurement capabilities at a price much lower than a traditional spectrum analyzer.The absolute power level and frequency performance of the...
Show moreThis thesis demonstrates the ability to use an existing software-defined radio for accurate RF measurements related to the precompliance testing of radiated emissions. The software-defined radio chosen for this work is the SDRplay Radio Spectrum Processor 2 Pro (RSP2pro). The RSP2pro was chosen because of its ability to provide absolute received power measurement capabilities at a price much lower than a traditional spectrum analyzer.The absolute power level and frequency performance of the RSP2pro has been characterized by direct comparison with an electromagnetic compatibility analyzer and the results are shown. A method for automating measurements taken with the RSP2pro companion software is described. The RSP2pro is also used to perform precompliance radiated emissions tests with an electromagnetic compatibility antenna and the results are discussed. Throughout this work a sample of three RSP2pro units is compared and variations in measurements across the three units is examined. A common very-high frequency "rabbit ear" television antenna and an ultra-high frequency "bowtie" television antenna are used with the RSP2pro to create a complete radiated emissions precompliance test setup. A procedure for characterizing these antennas and determining their suitability for radiated emissions precompliance testing is also described. The RSP2pro test setup for measuring radiated emissions is compared to a traditional precompliance test setup consisting of an electromagnetic compatibility spectrum analyzer and an electromagnetic compatibility antenna. This comparison includes a discussion of the relative cost, measurement accuracy, and overall convenience of using each test setup.
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Title: The intersection of race and sexuality in a national sample : examining discrimination and mental health
Creator: Wiklund, Lauren Olivia
Date: 2020
Collection: Electronic Theses & Dissertations
Description: The current study examined the experiences of race and sexuality related mistreatment in 2,335 racially diverse sexual minorities, the impact of those experiences on depression and anxiety symptoms, and the buffering effects of racial identity and social support. Zero inflated Poisson regression models were utilized for data analysis. Despite sexual minorities of color endorsing more frequent racial- and sexuality-based discrimination compared to their White counterparts, findings indicate...
Show moreThe current study examined the experiences of race and sexuality related mistreatment in 2,335 racially diverse sexual minorities, the impact of those experiences on depression and anxiety symptoms, and the buffering effects of racial identity and social support. Zero inflated Poisson regression models were utilized for data analysis. Despite sexual minorities of color endorsing more frequent racial- and sexuality-based discrimination compared to their White counterparts, findings indicate they had similar levels of anxiety and depression. Positive racial identity and social support varied by race. Importantly, social support was significantly associated with a decrease in depression and anxiety symptoms for Black sexual minorities with any symptoms. These findings suggest that at low levels of discrimination, sexual minorities of color appear to have resilience against some of the negative psychological consequences of experiencing both race- and sexuality-based discrimination, when compared to White sexual minorities. The resilience against racial discrimination, taught through racial socialization from an early age for many people of color, may generalize to resilience against sexuality-based discrimination. Given the variation of results across racial minorities, this study underscores the importance of an approach to race that preserves each racial groups' unique experiences of discrimination and mental health. Implications of a multidimensional approach to sexuality, challenges in addressing intersectional experiences, and considerations for clinicians working with these vulnerable populations are discussed.
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Title: HIV testing and associated characteristics among black cisgender and transgender women in the United States
Creator: Rutledge , Jaleah D.
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Background: In the United States, Black cisgender and transgender women are disproportionately affected by HIV. HIV testing is one of the primary modes of HIV prevention, but a large majority of the HIV testing literature focuses on individual level risk behaviors. Furthermore, there is little known about HIV testing among Black transgender women. This study aims to contribute to the existing literature by (1) examining the HIV testing behaviors of Black transgender women (2) using...
Show moreBackground: In the United States, Black cisgender and transgender women are disproportionately affected by HIV. HIV testing is one of the primary modes of HIV prevention, but a large majority of the HIV testing literature focuses on individual level risk behaviors. Furthermore, there is little known about HIV testing among Black transgender women. This study aims to contribute to the existing literature by (1) examining the HIV testing behaviors of Black transgender women (2) using socioecological theory to assess what sociodemographic factors are associated with HIV testing among Black cisgender and transgender women. Methods: This study uses secondary data from the 2014-2017 modules of the Behavioral Risk Factor Surveillance System. Analyses included multiple hierarchical regression. Results: There are no major differences in HIV testing between Black cisgender and transgender women. A number of sociodemographic characteristics have been shown to predict HIV testing among Black cisgender women, but only employment status and age were significant predictors of HIV testing among Black transgender women. A moderation analyses suggested that gender identity significantly moderates the association between employment status and HIV testing such that the relationship between employment status and receiving an HIV test differs by gender identity. Discussion: The findings of this study highlight nuances that are useful for improving HIV testing as a mode of HIV prevention. Overall, the findings contribute to our understanding of HIV testing practices among Black cisgender and transgender women.
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Title: Intra-household human capital measures and child and maternal health : evidence from Zambia
Creator: Faas, Simone Margaret
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Zambia has one of the highest rates of childhood stunting in the world. Traditional health production functions model that good health quality for young children is dependent on the necessary inputs of parental influences, including parental health, parental education, and household wealth. Using data from a Feed the Future survey from rural Zambia and the Women's Empowerment in Agriculture Index, I examine the relationship between several measures of spousal human capital and the health...
Show moreZambia has one of the highest rates of childhood stunting in the world. Traditional health production functions model that good health quality for young children is dependent on the necessary inputs of parental influences, including parental health, parental education, and household wealth. Using data from a Feed the Future survey from rural Zambia and the Women's Empowerment in Agriculture Index, I examine the relationship between several measures of spousal human capital and the health outcomes of young children and women of child-bearing age. I find the ability to read and write of both spouses is highly correlated with positive changes in children's and women's health outcomes. Literacy and education campaigns which target both boys and girls should be heavily emphasized among rural and disadvantaged communities in southern Africa, as men's literacy and education as well as women's literacy are both important to improving future health outcomes for children and adults.
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Title: BIOLOGICAL CONTROL OF THE INVASIVE BROWN MARMORATED STINK BUG (HALYOMORPHA HALYS) (HEMIPTERA : PENTATOMIDAE) IN MICHIGAN BY INTRODUCED AND NATIVE PARASTIOIDS IN A CHANGING CLIMATE
Creator: Simaz, Olivia Claire
Date: 2020
Collection: Electronic Theses & Dissertations
Description: This thesis focuses on evaluating the potential of native natural enemies and an exotic parasitoid to provide biological control of an invasive pest, the brown marmorated stink bug (Halyomorpha halys Stål) in Michigan and explores the consequences climate change might have both on the pest and its natural enemies. The first chapter provides background on the invasion of H. halys and reviews research on the native parasitoid community and their potential to provide biological control for this...
Show moreThis thesis focuses on evaluating the potential of native natural enemies and an exotic parasitoid to provide biological control of an invasive pest, the brown marmorated stink bug (Halyomorpha halys Stål) in Michigan and explores the consequences climate change might have both on the pest and its natural enemies. The first chapter provides background on the invasion of H. halys and reviews research on the native parasitoid community and their potential to provide biological control for this pest. The second chapter focuses on augmentative releases of the biological control agent, Trissolcus japonicus (Ashmead), which is an exotic parasitoid, discovered in Michigan in 2018. The importance of release size and of release frequency were tested during two years of augmentative releases and the native parasitoid community was surveyed. Overwintering success and reproduction of Tr. japonicus were confirmed but population growth was found slow. Parasitism by native parasitoids was below 5%, which is too low to provide control of H. halys. In the third chapter the effects of heat waves were evaluated on H. halys and Tr. japonicus. Eggs of H. halys were found to be more sensitive to heat waves than larval stages of Tr. japonicus. While heat waves did not reduce parasitism rates, Tr. japonicus adult mortality increased and their development was delayed with intensifying heat waves. These results suggest that Tr. japonicus could maintain its biocontrol potential even in the face of climate change.
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Title: Use of Recycled Aggregate Materials Characteristics in Pavement Design Analyses
Creator: Gheibi, Ida
Date: 2020
Collection: Electronic Theses & Dissertations
Description: Use of recycled materials promotes sustainability in roadway construction by reducing consumption of energy and emission of greenhouse gases associated with mining and the production of natural aggregates. Recycled asphalt pavements (RAP) and recycled concrete aggregates (RCA) have comparable characteristics to natural aggregates that are currently used in roadway base course applications. This study has developed a database for RAP and RCA materials’ characteristics including resilient...
Show moreUse of recycled materials promotes sustainability in roadway construction by reducing consumption of energy and emission of greenhouse gases associated with mining and the production of natural aggregates. Recycled asphalt pavements (RAP) and recycled concrete aggregates (RCA) have comparable characteristics to natural aggregates that are currently used in roadway base course applications. This study has developed a database for RAP and RCA materials’ characteristics including resilient modulus (Mr), California bearing ratio (CBR), gradations along with construction specifications. RAP and RCA relationships with different engineering and index properties were investigated and some trends were proposed such as higher RAP content reveals higher summary of resilient modulus (SMr), higher RCA content causes higher optimum moisture content (OMC) and lower maximum dry unit (MDU).In addition, pavement mechanistic-empirical (ME) analyses have been conducted with the material inputs collected for the database to determine whether different values of different characteristics of RCA and RAP can be used in flexible or rigid pavement designs. Results showed that Mr parameter had the highest impact on pavement distress predictions among gradations and hydraulic conductivity.
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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: 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: 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: Effects of olfactory and auditory stimuli on locomotion of procambarus clarkii
Creator: Clements, Douglas
Date: 2020
Collection: Electronic Theses & Dissertations
Description: This study addressed solutions for the population control of invasive Procambarus clarkii (Red Swamp Crayfish) in Michigan. The infestation was reported to the Michigan Department of Natural Resources in 2015. P. clarkii outcompetes native species of crayfish, is highly fecund and causes bank erosion through burrowing. Intensive trapping allows slowing the spread of the population and detecting new spread, but the practice is costly. In this study, auditory stimuli were tested as a means of...
Show moreThis study addressed solutions for the population control of invasive Procambarus clarkii (Red Swamp Crayfish) in Michigan. The infestation was reported to the Michigan Department of Natural Resources in 2015. P. clarkii outcompetes native species of crayfish, is highly fecund and causes bank erosion through burrowing. Intensive trapping allows slowing the spread of the population and detecting new spread, but the practice is costly. In this study, auditory stimuli were tested as a means of affecting a locomotive response in P. clarkii. These trials tested various pure tone sounds and pink and white noise ranges in artificial habitats. Following those results, a white noise frequency band was played underwater during the trapping season. The results indicated that a high frequency range of white noise (10-15 kHz) was most effective at eliciting a locomotory response. When used during the trapping season, a combination of sound and food bait performed at the highest capture per unit effort (CPUE), 0.820. Traps with only food and only sound performed at 0.644 and 0.675, respectively. Moreover, traps without sound or food bait performed at a high baseline CPUE of 0.487. Artificial refuge traps performed at a higher CPUE than other trap types, despite the lack of food bait. The results suggest that the benefits of refuge, sound, and food bait are additive. A novel trap design was created using the advantages of artificial refuge, food bait, and acoustic stimuli. The implications of this study span from the control of invasive species in the Great Lakes region to increasing profits of crayfish farming in the southern United States.
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Title: A social and biological evaluation of new zealand mudsnail invasion in michigan rivers
Creator: Tank, Samantha Nicole
Date: 2020
Collection: Electronic Theses & Dissertations
Description: New Zealand mudsnails (Potamopyrgus antipodarum; NZMS) are a small gastropod native to New Zealand and a documented worldwide invader. Michigan rivers are in the early phase of invasion, as NZMS were first detected in 2015 in the Pere Marquette River. In the early invasion process, information on likely vectors and the distribution of the species are critical to developing a well-informed management plan. My primary goals for this thesis were to address these informational needs. In order to...
Show moreNew Zealand mudsnails (Potamopyrgus antipodarum; NZMS) are a small gastropod native to New Zealand and a documented worldwide invader. Michigan rivers are in the early phase of invasion, as NZMS were first detected in 2015 in the Pere Marquette River. In the early invasion process, information on likely vectors and the distribution of the species are critical to developing a well-informed management plan. My primary goals for this thesis were to address these informational needs. In order to document the distribution of NZMS, I developed a sampling methodology and evaluated its effectiveness, as standard methods for lotic sampling NZMS have not been developed in the literature. I conducted a total of 227 surveys in 12 Michigan rivers between 2015 and 2018. Survey data were analyzed using an occupancy model, resulting in a per survey detectability exceeding 96%. NZMS were detected in 5 Michigan rivers: the Pere Marquette, Boardman, Manistee, Au Sable, and Pine rivers. I estimate that more than 65 river kilometers within the Pere Marquette, Boardman, and Pine rivers are infested. The distribution of NZMS suggests discrete transport events, and that the introduction into Michigan likely occurred well before the first reported detection of this species. The literature indicates that the wading gear of anglers is the main vector of transport within and between rivers. I surveyed 308 anglers fishing the Pere Marquette River in 2016-2017. Even though 52% of anglers were aware of NZMS, there was not a significant difference in wader cleaning behaviors between anglers aware or unaware of NZMS, indicating that outreach efforts need to focus beyond the awareness stage. As no in-stream method of treatment is presently available, angler engagement should be a focus of future management efforts.
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