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Title: SOCIAL DETERMINANTS OF BREASTFEEDING : THE ROLE OF PRENATAL FOOD INSECURITY
Creator: Robinson, Chelsea
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Background: Relatively little work has quantified associations between prenatal food insecurity and breastfeeding practices; however, understanding the implications of prenatal food insecurity may support food insecurity screening recommendations during prenatal care. Therefore, the purpose of this study was to investigate associations between prenatal food insecurity and breastfeeding initiation and duration until 3 months postpartum. Method: This study utilized data from a prospective...
Show moreBackground: Relatively little work has quantified associations between prenatal food insecurity and breastfeeding practices; however, understanding the implications of prenatal food insecurity may support food insecurity screening recommendations during prenatal care. Therefore, the purpose of this study was to investigate associations between prenatal food insecurity and breastfeeding initiation and duration until 3 months postpartum. Method: This study utilized data from a prospective Michigan pregnancy cohort. Women were recruited during their first prenatal visit with planned follow-up through early childhood. Prenatal food insecurity was assessed during pregnancy, and breastfeeding initiation and duration were assessed at the 3-month postpartum visit. Multiple logistic regression models were used to evaluate associations between prenatal food insecurity and the two primary outcomes: breastfeeding initiation and breastfeeding status at 3-months postpartum. Cox proportional hazard ratios were used to assess differences in the risk of breastfeeding cessation until 3 months postpartum by food insecurity status. An adversity index was created to stratify women into higher- and lower-risk groups for not breastfeeding. Associations between food insecurity and breastfeeding at 3 months postpartum (yes/no) were assessed via Fisher’s Exact test within each group. Results: In the unadjusted models, women who reported food insecurity during pregnancy were less likely to initiate breastfeeding (OR = 0.39; 95% CI: 0.21-0.69) and continue breastfeeding until 3 months postpartum (OR = 0.35; 95% CI: 0.20-0.61) compared to food secure women, but the associations were no longer significant after adjustment for sociodemographic and health-related factors. Prenatal food insecurity was not associated with breastfeeding at 3 months postpartum in analyses stratified into high- and low-adversity groups. Conclusions: Prenatal food insecurity is a strong predictor of breastfeeding practices. Though not significantly associated with breastfeeding practices after adjustment, screening for prenatal food insecurity may help clinicians identify women who may need more supports to initiate and maintain breastfeeding.
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Title: A PILOT STUDY OF WEB-BASED INFORMATION BOTTLENECK IDENTIFICATION IN AEC PROJECTS
Creator: Pandey, Nishchhal Nihal
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The success of the Architecture, Engineering, and Construction (AEC) project relies heavily on the effective communication and information exchange between project team members. A prominent reason for delays and progress shortcomings in AEC project teams is information bottlenecks, defined as missing project information bits which can be due to large influx of information or inadvertent withholding of information at a particular time. Information bottlenecks both in planning and execution...
Show moreThe success of the Architecture, Engineering, and Construction (AEC) project relies heavily on the effective communication and information exchange between project team members. A prominent reason for delays and progress shortcomings in AEC project teams is information bottlenecks, defined as missing project information bits which can be due to large influx of information or inadvertent withholding of information at a particular time. Information bottlenecks both in planning and execution phases of the project tend to cause schedule delays and cost overruns. Information and communication exchange patterns between project team members shed a light on the possible occurrence of information bottlenecks. Recent literature efforts have focused on use of software programming and key performance indicators (KPIs) to identify which phases of project are prone to occurrence of bottlenecks. One of the roadblocks in implementing majority of bottleneck identification techniques in AEC projects is the difficulty in execution. Some of the metrics defined are too complex and require rigorous manual calculations. Given the complexity and feasibility difficulties of the present methodologies for identification of bottleneck, this study aims to contribute to the body of knowledge by providing an adaptable tool that aims to improve the accuracy and practicality for predicting bottlenecks. Therefore, the research question this research aims to answer is “Can the usability and adaptability of information bottleneck prediction in AEC projects be improved through a web-based tool?”Expanding on Lean Construction concepts, key performance indicators (KPIs), efficiency, quantification metrics are developed to study the trends of information shared between AEC project team members. The developed model is semi-automated and reads data by importing the Microsoft Excel sheet which has all the raw project documentation data. A Python code developed by the researcher is used to extract information from the excel, create a dashboard, and publish information bottleneck calculations through a web-based tool. Statistical inferences drawn from the model are then be used to identify occurrence of project bottlenecks. The web-based platform is designed to cater the specific information exchange trends in a typical project. Providing visual representations, and explanations further ease the understanding of the root issue. Finally, through two expert interviews, the web tool is revised, and final tool is presented, and future directions of work are discussed.
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Title: INDIGENOUS MENTAL HEALTH : EXAMINING POPULATIONS IN TRIBAL AREAS AND NON-TRIBAL AREAS
Creator: Nash, Madeline
Date: 2022
Collection: Electronic Theses & Dissertations
Description: In this paper, I hypothesize that Indigenous populations in tribal areas fare better than those populations residing outside of tribal areas because of stronger social ties due to higher levels of integration and regulation. I review some of the studies that have been undertaken to measure mental health outcomes and suicide rates for the Indigenous populations in the US and Canada, paying close attention to the studies that describe differences between populations residing in tribal areas...
Show moreIn this paper, I hypothesize that Indigenous populations in tribal areas fare better than those populations residing outside of tribal areas because of stronger social ties due to higher levels of integration and regulation. I review some of the studies that have been undertaken to measure mental health outcomes and suicide rates for the Indigenous populations in the US and Canada, paying close attention to the studies that describe differences between populations residing in tribal areas compared to those who do not. I then use a panethnicity/race as a fundamental cause approach to explain why Indigenous populations have disparate mental health outcomes compared to the rest of the population, utilizing structural genocide to explain diminished integration and regulation. Pooling data from the National Drug Use and Health Survey (NSDUH), 2014-2017, I test this hypothesis controlling for sociodemographic variables. The results are mixed. On measures of serious psychological distress (SPD), my results are consistent with Park-Lees et al (2018). findings that there is no significant difference between these populations. However, there is a significant difference in serious thoughts of suicide. This contradicts Park-Lee et al. findings that though people residing in tribal areas had a lower rate than those who resided outside of tribal areas—the difference was not statistically significant using a T-test (2018). I found in my regression that after controlling for gender, age, marital status, education and income that living in tribal areas lowered one’s odd of having serious thought of suicide by over 30%.
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Title: EXPLORING THE RELATIONSHIP BETWEEN RESILIENCE AND ADVERSE IMPACT OF STUTTERING
Creator: Grobbel, Hannah
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Children who stutter often experience adverse impact such as bullying, negative thought patterns, and reduced self-esteem that result from living with their condition. Research suggests that there are factors that may place a child who stutters at greater risk for adverse impact as well as protective factors that mitigate this risk. The aim of this study is to examine the relationship between resilience and stuttering’s adverse impact in children. Resilience reflects both internal factors...
Show moreChildren who stutter often experience adverse impact such as bullying, negative thought patterns, and reduced self-esteem that result from living with their condition. Research suggests that there are factors that may place a child who stutters at greater risk for adverse impact as well as protective factors that mitigate this risk. The aim of this study is to examine the relationship between resilience and stuttering’s adverse impact in children. Resilience reflects both internal factors such as grit and the ability to cope and external factors such as family support and access to resources. We collected data from children who stutter and their parents to assess children’s resilience and stuttering’s adverse impact using standardized assessments. We then explored the relationship between resilience and adverse impact through descriptive statistics, linear regression, and correlation analyses. Results revealed that even children in the youngest, preschool-aged group showed adverse impact due to stuttering. We also found that greater resilience predicted less adverse impact in in school-aged and adolescent children who stutter. These findings provide insight into the experience of stuttering and offer support for treatments that incorporate resilience building into therapy to help mitigate adverse impact experienced by children who stutter.
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Title: THE USE OF EQUIVALENCE-BASED INSTRUCTION TO TEACH GRADUATE STUDENTS SIMPLIFIED DEFINITIONS OF BEHAVIOR ANALYTIC TERMINOLOGY
Creator: Medlin, Grace
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Individuals who are pursuing their Board-Certified Behavior Analyst (BCBA) certification are required to have an effective understanding of applied behavior analysis (ABA) terminology. Hemwell (2020) used Equivalence Based Instruction (EBI) and Match-to-Sample (MTS) training to teach technical definitions of ABA terminology to first-year ABA students. Participants displayed limited emergent intraverbal responding and did not maintain emergent intraverbal responding. Hemwell (2020) speculated...
Show moreIndividuals who are pursuing their Board-Certified Behavior Analyst (BCBA) certification are required to have an effective understanding of applied behavior analysis (ABA) terminology. Hemwell (2020) used Equivalence Based Instruction (EBI) and Match-to-Sample (MTS) training to teach technical definitions of ABA terminology to first-year ABA students. Participants displayed limited emergent intraverbal responding and did not maintain emergent intraverbal responding. Hemwell (2020) speculated this was due to the length and complexity of the definitions. The current study was conducted to replicate and extend Hemwell (2020) to determine if using simplified definitions of ABA terminology was effective in promoting the acquisition, understanding, and maintenance of ABA terminology. Using a multiple probe across behaviors design replicated across participants, participants were exposed to 30 simplified ABA terms, along with definitions and examples via a MTS teaching method. Participants were assessed on their performance of untaught relations in a selection-based pre-post assessment, as well as through a written intraverbal probes. Despite text simplification, emergent intraverbal responding was variable and did not maintain for all terms. However, emergent selection-based responding across all relations from pre to post test was evident. In addition, following text simplification, participants displayed emergent selection based responding with more complex definitions from the Cooper et al. (2020) textbook. Overall, future instructors may consider the use of EBI and text simplification in their courses to teach ABA terminology, examples, and principles.
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Title: Accessible Communication for Teaching App Research and Prototype
Creator: Tetu, Imari Cheyne
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Academia has traditionally served students who are able-bodied and able-minded. To include students with physical and cognitive disabilities, colleges and universities need to consider forms of engagement and participation that do not place disabled students at a disadvantage. Remote learning tools, such as those available in Zoom and Microsoft Teams, provide alternate means of communication that would be useful in classes with face-to-face meetings. I propose an app for use in post-secondary...
Show moreAcademia has traditionally served students who are able-bodied and able-minded. To include students with physical and cognitive disabilities, colleges and universities need to consider forms of engagement and participation that do not place disabled students at a disadvantage. Remote learning tools, such as those available in Zoom and Microsoft Teams, provide alternate means of communication that would be useful in classes with face-to-face meetings. I propose an app for use in post-secondary hybrid and hyflex writing classrooms. This app will facilitate networked communication among student groups as well as between individual students and instructors. I use design and accessibility heuristics to develop the wireflow through iterative design with a focus on the varying needs of people with physical and cognitive disabilities.
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Title: COVID-19 information sharing on social media : Channels and Motives from the Kazakhstani people's perspective
Creator: Moldagaliyeva, Moldir
Date: 2022
Collection: Electronic Theses & Dissertations
Description: COVID-19 pandemic news has become popular and topical content for the last couple of years. And the wide usage of social media across the globe makes it easy to share information, including misinformation, about COVID-19. Although sharing news on social media has been actively studied in most western countries, little attempt has been made to look into the issue from the perspectives of developing countries where the amount of social media use has been increasing enormously over the last...
Show moreCOVID-19 pandemic news has become popular and topical content for the last couple of years. And the wide usage of social media across the globe makes it easy to share information, including misinformation, about COVID-19. Although sharing news on social media has been actively studied in most western countries, little attempt has been made to look into the issue from the perspectives of developing countries where the amount of social media use has been increasing enormously over the last years. Besides, almost nothing is known about the social media users’ choice of a particular platform when they decide to share information and misinformation, especially within the context of the COVID-19 pandemic. Therefore, this master’s thesis explored how motivation factors Kazakhstani people follow when sharing COVID-19 news shape their decision to share COVID-19 news on specific social media platforms and their COVID-19 misinformation sharing patterns.The study used a quantitative research method approach, surveying 288 people from Kazakhstan over 18 years old.
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Title: Navigating Ideology, Identity, and Emotion in the Context of English-Medium Higher Education : Zohra's Story
Creator: Zulick, Bethany
Date: 2022
Collection: Electronic Theses & Dissertations
Description: There is a growing prevalence of English-medium instruction (EMI) at universities around the world as a result of globalization and the internationalization of higher education. Although the English language is often the main language of these institutions, research shows that the local language often occupies an important position within these institutions. This linguistic environment places international students who do not speak the local language in a vulnerable position, and they may...
Show moreThere is a growing prevalence of English-medium instruction (EMI) at universities around the world as a result of globalization and the internationalization of higher education. Although the English language is often the main language of these institutions, research shows that the local language often occupies an important position within these institutions. This linguistic environment places international students who do not speak the local language in a vulnerable position, and they may face exclusion from social settings or have less access to some aspects of academic life as a result. The present study examines how ideology, identity, and emotion interact in one international student’s journey through her first year at an EMI institution in Kyrgyzstan as she navigates language use within the institution, cultivates her multilingual repertoire, and creates a place for herself in the institutional community. The findings of the study revealed how the focal participant, Zohra, was influenced by monolingual ideologies, viewing the institution as a primarily English-only space and attempting to uphold these norms through her own language use. Like other international students, Zohra also reported experiences of exclusion through the use of the local language, positioning her as an outsider and provoking a range of negative emotions in response. Zohra leveraged her strong English skills and strategically used the local language to construct a positive identity for herself as a full member of the university community. She also engaged in an iterative process of reflection as she compartmentalized her personally held language ideologies and managed her negative emotions surrounding language use to facilitate her adjustment to the university.
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Title: Memory-efficient emulation of physical tabular data using quadtree decomposition
Creator: Carlson, Jared
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Computationally expensive functions are sometimes replaced in simulations with an emulator that approximates the true function (e.g., equations of state, wavelength-dependent opacity, or composition-dependent materials properties). For functions that have a constrained domain of interest, this can be done by discretizing the domain and performing a local interpolation on the tabulated function values of each local domain. For these so-called tabular data methods, the method of discretizing...
Show moreComputationally expensive functions are sometimes replaced in simulations with an emulator that approximates the true function (e.g., equations of state, wavelength-dependent opacity, or composition-dependent materials properties). For functions that have a constrained domain of interest, this can be done by discretizing the domain and performing a local interpolation on the tabulated function values of each local domain. For these so-called tabular data methods, the method of discretizing the domain and mapping the input space to each subdomain can drastically influence the memory and computational costs of the emulator. This is especially true for functions that vary drastically in different regions. We present a method for domain discretization and mapping that utilizes quadtrees, which results in significant reductions in the size of the emulator with minimal increases to computational costs or loss of global accuracy. We apply our method to the electron-positron Helmholtz free energy equation of state and show over an order of magnitude reduction in memory costs for reasonable levels of numerical accuracy.
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Title: Sustainable Public Place Development with Community Participant Process : A Case Study of Belle Isle Park, MI
Creator: Guminik, Bridget
Date: 2022
Collection: Electronic Theses & Dissertations
Description: There are many positive influences from greenspaces which are even more crucial in large urban cities such as Detroit, Michigan. The abandoned area of the old Belle Isle Park Zoo has been the subject of numerous redevelopment proposals. However, there is a gap in what designers have done and what this research proposes, which is that previous designs lacked community engagement. The purpose of this study is to demonstrate the importance and value in including community engagement into design...
Show moreThere are many positive influences from greenspaces which are even more crucial in large urban cities such as Detroit, Michigan. The abandoned area of the old Belle Isle Park Zoo has been the subject of numerous redevelopment proposals. However, there is a gap in what designers have done and what this research proposes, which is that previous designs lacked community engagement. The purpose of this study is to demonstrate the importance and value in including community engagement into design choices. With a series of public workshops with stakeholders, landscape performance research has been adopted to assess the impact of the final design proposal. The success of a final design after community engagement aims to promote the use of community engagement in design as a beneficial and necessary factor when installing public space developments. The study will utilize the abandoned zoo space in Belle Isle Park to demonstrate that the community will benefit more from having input in what changes are made to their own community spaces while still allowing the designers room to implement environmental and socioeconomic beneficial tactics.
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Title: Contextual Support, Resilience, Allostatic Load, and Mental Health in Transgender and Gender Diverse Individuals
Creator: Kimball, Devon Mary
Date: 2022
Collection: Electronic Theses & Dissertations
Description: A growing body of literature suggests that how much support TGD individuals experience in the places they live, including their present context and context of origin, can influence their wellbeing. Other research about physical health has found exposure to stressors has physiological effects on sexual and gender minority people, which can be measured through allostatic load (a selection of multiple physiological indicators that reflects “wear and tear” on the body; AL). Research on mental...
Show moreA growing body of literature suggests that how much support TGD individuals experience in the places they live, including their present context and context of origin, can influence their wellbeing. Other research about physical health has found exposure to stressors has physiological effects on sexual and gender minority people, which can be measured through allostatic load (a selection of multiple physiological indicators that reflects “wear and tear” on the body; AL). Research on mental health has also indicated that TGD individuals are at higher risk of depression and anxiety. TGD populations also have unique resilience factors that are important to consider, such as pride and community connectedness, which may influence health outcomes. This study used latent class analysis to examine how individuals clustered based on current and past levels of contextual support, and then examined the relationship between these classes and AL, depression, and anxiety, including whether pride and community connectedness moderated these relationships. Contextual support across the lifetime was also examined as a continuous variable. Participants either had lived consistently in contexts with high levels of support (High Support class), had moved from contexts with low levels of support to high levels of support (Low to High Support class), or had consistently lived in contexts with low levels of support (Low Support class). Individuals in the Low Support class had lower levels of AL compared to their peers in the High Support class. There were no associations between class and depression and anxiety, and there were no moderating effects of community connectedness or pride. This study suggests that contextual support may not influence depression and anxiety among TGD people, but that lower levels of support may actually correlate with decreased AL.
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Title: Learning Fair Representations without Demographics
Creator: Wang, Xiaoxue
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Due to hard accessibility, real-world adoption of fair representation learning algorithms lacks the prior knowledge of the sensitive attributes that we wish to be fair with. To address the challenge in fairness without explicit demographics, our solution is based on the idea of maximally randomizing the representation while being as informative as possible about the target task. We operationalize this goal through the concept of maximizing the entropy of the learned representation. For this...
Show moreDue to hard accessibility, real-world adoption of fair representation learning algorithms lacks the prior knowledge of the sensitive attributes that we wish to be fair with. To address the challenge in fairness without explicit demographics, our solution is based on the idea of maximally randomizing the representation while being as informative as possible about the target task. We operationalize this goal through the concept of maximizing the entropy of the learned representation. For this purpose, we propose two new avenues for entropy maximization in the absence of demographic information: intra-class and inter-class entropy maximization. For 1) intra-class entropy maximization, it maximizes the entropy of the non-target class predictions (excluding the probability of the ground truth class label for classification problems), thus encouraging the model to discard spurious correlations between the different target classes, and for 2) inter-class entropy maximization, it maximizes the entropy of the representation conditioned on the target label, thus encouraging randomization of the samples within each target class label and minimizing the leakage of potential demographic information in the representation. Quantitative and qualitative results of our Maximum Entropy method (MaxEnt) on COMPAS and UCI Adult datasets show that 1) our method can outperform the State-of-the-art (SOTA) Adversarially Reweighted Learning (ARL) method and will enhance the difficulty of extracting sensitive demographic information in representation without prior demographic knowledge 2) our method reaches a good trade-off between utility and fairness.
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Title: Evaluation of potential therapeutics for non-small cell lung cancer using 3D tumor spheroid models
Creator: Stoub, Hayden Eric
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The development of novel and improved therapies for cancers requires robust means of investigation that both effectively recapitulate tumor biology while also utilizing resources efficiently. 3D tissue culture methods, namely spheroids and organoids, have emerged as an effective bridge between conventional in vitro methods and in vivo animal models in cancer research. This thesis provides background into lung cancer and the current landscape of 3D in vitro models of cancer, as well as...
Show moreThe development of novel and improved therapies for cancers requires robust means of investigation that both effectively recapitulate tumor biology while also utilizing resources efficiently. 3D tissue culture methods, namely spheroids and organoids, have emerged as an effective bridge between conventional in vitro methods and in vivo animal models in cancer research. This thesis provides background into lung cancer and the current landscape of 3D in vitro models of cancer, as well as detailing two studies in which multicellular tumor spheroids were used to investigate the therapeutic potential of candidate compounds. The first study uses an NCI-H358 multicellular tumor spheroid to investigate three compounds: Apigenin, a plant derived flavonoid; MSU42011, a novel retinoid x receptor (RXR) agonist; and CEP-1347, a mixed lineage kinase (MLK) inhibitor. It was found that Apigenin alone decreased the viability of spheroids, and that the combination of Apigenin and CEP-1347 synergistically decreased viability and increased cell death within the spheroids.The second study uses a murine lung adenocarcinoma tumor spheroid model to investigate the effects of MSU-71, a novel inhibitor of the nuclear factor erythroid 2-related factor (NRF2) pathway, on macrophage-induced invasion and migration. This compound blocked both migration in conventional experiments along with spheroid invasion, indicating its potential efficacy in preventing LUAD progression. This study also adapted the spheroid invasion model for use in multiple human LUAD cell lines and THP-1 conditioned medium. The findings presented herein demonstrate the versatility and value of 3D tumor spheroid models in the cancer drug development field.
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Title: Training Behavior Technicians to Implement Naturalistic Object Imitation Using Behavioral Skills Training
Creator: Walker, Ashley N.
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The purpose of this study was to evaluate the effects of Behavioral Skills Training (BST) on teaching behavior technicians to implement imitation training, in the form of naturalistic behavioral interventions, to a confederate adult. Using a concurrent multiple baseline across participants design, participants were exposed to baseline conditions and given the instruction to teach the adult confederate how to imitate. Then, participants were exposed to a single BST session. Following BST,...
Show moreThe purpose of this study was to evaluate the effects of Behavioral Skills Training (BST) on teaching behavior technicians to implement imitation training, in the form of naturalistic behavioral interventions, to a confederate adult. Using a concurrent multiple baseline across participants design, participants were exposed to baseline conditions and given the instruction to teach the adult confederate how to imitate. Then, participants were exposed to a single BST session. Following BST, participant behavior was monitored further in the presence of the confederate. Results suggest BST resulted in an improvement in imitation training for all three participants. Limitations and future directions are discussed.
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Title: Progress toward chemical identification of the sea lamprey (Petromyzon marinus) alarm cue
Creator: Mensch, Emily Lauren
Date: 2022
Collection: Electronic Theses & Dissertations
Description: This thesis examined the chemical constituents of repellent odors in the sea lamprey (Petromyzon marinus), an invasive fish in the Great Lakes basin, for use in management and conservation. Odors are powerful tools that guide organism’s movement decisions, and repellent odors such as conspecific alarm cues are particularly potent. In chapter one, we investigated the chemistry of the alarm cue through behaviorally guided fractionation. We found substantial avoidance responses to two major...
Show moreThis thesis examined the chemical constituents of repellent odors in the sea lamprey (Petromyzon marinus), an invasive fish in the Great Lakes basin, for use in management and conservation. Odors are powerful tools that guide organism’s movement decisions, and repellent odors such as conspecific alarm cues are particularly potent. In chapter one, we investigated the chemistry of the alarm cue through behaviorally guided fractionation. We found substantial avoidance responses to two major fractions: water-soluble and chloroform soluble and a full avoidance response upon recombination of the two fractions. We found no consistent avoidance patterns to subfractions, or individual compounds identified in the water-soluble fraction, and we found no avoidance response to all 32 identified compounds from the water-soluble fraction when combined at observed ratios in the skin. In chapter two, we investigated the role of a potential repellent molecule, putrescine, on sea lamprey activity and avoidance in a small individual behavioral assay and avoidance in a large, multi-animal assay. We found a context-dependent response, where sea lamprey did not increase activity in the small assay but did show a substantial avoidance response to putrescine. No evidence of avoidance to putrescine was observed in the large assay. In sum, these results suggest the alarm cue is likely not contained in the 32 identified compounds in the water-soluble-fraction alone and that the behavioral response to putrescine is context dependent. While elucidating the chemistry of the sea lamprey alarm cue may be more difficult than through behaviorally guided fractionation alone, the continued pursuit is worthwhile because of the utility in invasive species management and conservation of native species.
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Title: HIGH SURFACE AREA ZINC ELECTRODE FOR FURFURAL ELECTROCATALYTIC HYDROGENATION
Creator: Lee, Seungyeon
Date: 2022
Collection: Electronic Theses & Dissertations
Description: With the increasing need to achieve carbon neutrality, electrocatalytic hydrogenation (ECH) of biomass-derived oxygenates, such as furfural, has received growing interest. Biomass ECH is an eco-friendly conversion of an abundant resource to valuable chemical products like fuels that replace fossil resources. In this study, we focus on high surface-area zinc nanoparticles as a catalyst for furfural ECH. The rotating disk electrode (RDE) is employed to enable quick electrochemical studies with...
Show moreWith the increasing need to achieve carbon neutrality, electrocatalytic hydrogenation (ECH) of biomass-derived oxygenates, such as furfural, has received growing interest. Biomass ECH is an eco-friendly conversion of an abundant resource to valuable chemical products like fuels that replace fossil resources. In this study, we focus on high surface-area zinc nanoparticles as a catalyst for furfural ECH. The rotating disk electrode (RDE) is employed to enable quick electrochemical studies with small surface area, and kinetic parameters were obtained via Koutecký-Levich analysis. To modify a glassy carbon RDE with zinc nanoparticles, Nafion®, polyvinyl pyrrolidone (PVP), and polyvinyl alcohol (PVA) were studied as binders. In the absence of furfural, chronoamperometry of PVA-bound zinc electrodes showed continuous steady current associated with the hydrogen evolution reaction (HER). In contrast, Nafion® and PVP bound electrodes were found to be unstable. In the presence of furfural, high electrocatalytic activity was achieved with Zn-PVA compared to glassy carbon. The Zn-PVA electrode was optimized by varying the binder content and total zinc loading. A weak optimum was identified at 92 wt% zinc and 8.6 mgZn/cm2 loading. For zinc electrodes, high FE was obtained at higher overpotential (-0.9V vs. RHE), whereas higher FE was obtained at lower overpotentials for copper. Through Koutecký-Levich analysis, kinetic current densities and moderate Tafel slopes were observed, suggesting that the high surface-area zinc electrode is a promising platform for ECH. Product analysis studies using GC-MS are suggested to verify FE and to further elucidate the mechanism of furfural ECH at zinc electrodes.
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Title: USING EXISTING INFRASTRUCTURE AS GROUND CONTROL TO SUPPORT CITIZEN SCIENTIST COASTAL UAS MONITORING PROGRAMS
Creator: Rabins, Lucas Frederick
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Recent publications have described the ability of citizen scientists to conduct unoccupied aerial system (UAS) flights to collect data for coastal management. Ground control points (GCPs) can be collected to georeference these data, however collecting GCPs require expensive surveying equipment not accessible to citizen scientists. Instead, existing infrastructure can be used as naturally occurring GCPs (NGCPs), although availably of NGCP placement on such infrastructure differs from published...
Show moreRecent publications have described the ability of citizen scientists to conduct unoccupied aerial system (UAS) flights to collect data for coastal management. Ground control points (GCPs) can be collected to georeference these data, however collecting GCPs require expensive surveying equipment not accessible to citizen scientists. Instead, existing infrastructure can be used as naturally occurring GCPs (NGCPs), although availably of NGCP placement on such infrastructure differs from published best practices of GCP placement. This study therefore evaluates the achievable accuracy of sites georeferenced with NGCPs through an analysis of 20 diverse coastal sites. At most sites NGCPs produced horizontal and vertical root mean square errors (RMSE) less than 0.060 m which are similar to those obtained using traditional GCPs. To support future UAS citizen science coastal monitoring programs, an assessment to determine the optimal NGCP quantity and distribution was conducted for six coastal sites. Results revealed that generally at least seven NGCPs collected in the broadest distribution across the site will result in a horizontal and vertical RMSE less than 0.030 m and 0.075 m respectively. However, the relationship between these placement characteristics and RMSE was poor, indicating that georeferencing accuracy using NGCPs cannot be optimized solely through ideal quantity and distribution. The results of these studies highlight the value of NGCPs to support UAS citizen science coastal monitoring programs, however they also indicate a need for an initial accuracy assessment of sites surveyed with NGCPs at the onset of such programs.
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Title: Examination of soilborne pathogens of celery in Michigan
Creator: Peterson, Annika
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Michigan celery field and greenhouse yield and quality is negatively impacted by soilborne pathogens. Celery growers have observed a crown rot, wilt, and vascular discoloration called “meltdown”. Symptomatic celery plants were collected from seven grower commercial grower fields across four counties and two years. Isolations showed the most common organisms observed were Fusarium solani species complex (52%) and Fusarium oxysporum species complex (45%) as identified by sequencing of the...
Show moreMichigan celery field and greenhouse yield and quality is negatively impacted by soilborne pathogens. Celery growers have observed a crown rot, wilt, and vascular discoloration called “meltdown”. Symptomatic celery plants were collected from seven grower commercial grower fields across four counties and two years. Isolations showed the most common organisms observed were Fusarium solani species complex (52%) and Fusarium oxysporum species complex (45%) as identified by sequencing of the translation elongation factor-1α. Isolates identified as Fusarium oxysporum f. sp. apii race 2 (Foa race 2), the cause of Fusarium yellows, using diagnostic primers caused disease in a growth chamber pathogenicity assay. Foa race 2 isolates are capable of causing disease symptoms but are infrequent so “meltdown” may have additional cause(s). Pythium root rot decreases quality of greenhouse grown celery transplants. Pythium spp. isolated from symptomatic celery seedlings were characterized by virulence and fungicides tested for control of Pythium root rot. The most frequent Pythium species collected from Michigan celery were P. mastophorum (55%), P. intermedium (16%), P. sulcatum (10%), P. aff. diclinum (6%), and P. sylvaticum (5%). P. sulcatum and P. sylvaticum caused disease symptoms on celery seedlings in a greenhouse virulence assay. Phosphorous acid salts, ethaboxam, and mefenoxam controlled Pythium root rot in a greenhouse setting. Results indicate which Pythium spp. are of most concern to celery growers and identify effective chemical controls. Understanding presence and virulence of soilborne plant pathogens in Michigan celery production will be used to develop strategies to limit disease.
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Title: BLAME JUDGEMENTS FOR PAST ACTIONS OF GROUPS
Creator: Vallabha, Shree
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Historically, groups have committed innumerable atrocities, including genocide and slavery. I tested if people blame current groups for the actions of their past members and what underlies this blame. Current models of blame overlook the dimension of time and therefore have difficulty explaining this phenomenon. I hypothesized that perceiving higher (a) connectedness between past and present perpetrator groups, (b) unfulfilled obligations of perpetrator groups, (c) continued privilege of...
Show moreHistorically, groups have committed innumerable atrocities, including genocide and slavery. I tested if people blame current groups for the actions of their past members and what underlies this blame. Current models of blame overlook the dimension of time and therefore have difficulty explaining this phenomenon. I hypothesized that perceiving higher (a) connectedness between past and present perpetrator groups, (b) unfulfilled obligations of perpetrator groups, (c) continued privilege of perpetrator groups, and (d) continued harm of victim groups would facilitate higher blame judgements against current groups for the past. In a survey (N=518) using real events, I find results consistent with all the four hypotheses and some preliminary evidence for group differences in these relationships. I find that factors that link the present group to the past explain why groups are blamed for their past actions. These findings bring to light the deficiencies in existing theories of blame – calling into question its assumptions and incomplete criterion of judgement.
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Title: IMPROVING YIELD AND QUALITY OF LEAFY GREENS GROWN INDOORS WITH PRECISE RADIATION, TEMPERATURE, AND CARBON DIOXIDE MANAGEMENT
Creator: Tarr, Sean T.
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Indoor agriculture systems can allow for precise manipulation of the mean daily temperature (MDT), carbon dioxide (CO2) concentration, and photosynthetic photon flux densities (PPFD). Identifying how these environmental parameters interact to influence crop growth, development, yield, and color can assist growers with selecting their desired growing environment. Therefore, the objectives of Expt. 1 and 2 were to quantify and model how PPFD and CO2 concentrations interact with MDT to influence...
Show moreIndoor agriculture systems can allow for precise manipulation of the mean daily temperature (MDT), carbon dioxide (CO2) concentration, and photosynthetic photon flux densities (PPFD). Identifying how these environmental parameters interact to influence crop growth, development, yield, and color can assist growers with selecting their desired growing environment. Therefore, the objectives of Expt. 1 and 2 were to quantify and model how PPFD and CO2 concentrations interact with MDT to influence the growth, yield, and quality of hydroponically grown green butterhead ‘Rex’ and red oakleaf lettuce ‘Rouxaï RZ’. In Expt. 3 we developed models to predict growth parameters and cardinal temperatures of lettuce, arugula, and kale from 8 to 33 °C. In Expt. 1, lettuce ‘Rex’ and ‘Rouxaï RZ’ were grown in deep-flow hydroponic tanks under a PPFD of 150 or 300 μmol·m‒2·s‒1 for 17 h·d–1 at MDTs of 20, 23, or 26 °C. PPFD and MDT interacted to influence biomass accumulation of both cultivars. In Expt. 2, lettuce ‘Rex’ and ‘Rouxaï RZ’ were grown under a PPFD of 300 μmol·m‒2·s‒1 and at the same MDTs as Expt. 1, but with CO2 concentrations of 500, 800, or 1200 μmol·mol–1. Dry mass of both cultivars was influenced by the interaction of CO2 and MDT; biomass accumulation was greatest at 800 μmol·mol–1 CO2 at MDTs of 23 and 26 °C. In Expt. 3, ‘Rex’ and ‘Rouxaï RZ’, kale ‘Red Russian’, and arugula ‘Astro’ were grown at MDTs of 8, 13, 18, 23, 28, or 33 °C. ‘Rex’ and ‘Rouxaï RZ’ had similar base and optimal temperature estimates of 8 °C and 26 °C, while arugula and kale were lower at 6 °C and 23 °C.
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