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Title: The influence of anisotropic slip and shear transformation on heterogeneous deformation based upon nanoindentation, crystal plasticity modeling, and artificial neural networks
Creator: Zhao, Zhuowen
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Most technological relevant structural materials are polycrystals that contain many (millions) so-called grains. Plastic deformation in polycrystalline metallic materials is not homogeneous at the microscale, but sometimes strongly heterogeneous among grains and varies spatially within an individual grain. The ability to predict the magnitude and spatial distribution of plastic inhomogeneity, particularly near grain boundaries (GBs), is crucial as it often results in a stress concentration...
Show moreMost technological relevant structural materials are polycrystals that contain many (millions) so-called grains. Plastic deformation in polycrystalline metallic materials is not homogeneous at the microscale, but sometimes strongly heterogeneous among grains and varies spatially within an individual grain. The ability to predict the magnitude and spatial distribution of plastic inhomogeneity, particularly near grain boundaries (GBs), is crucial as it often results in a stress concentration that could lead to nucleation of damage sites, which largely affect the lifetime of stressed components. Accurate modeling of such inhomogeneity depends on the reliable description of basic plastic micro-mechanisms, e.g., dislocation slip, and fine details such as interactions between slip and GBs. This study aims to facilitate the above need by 1) establishing consistent critical resolved shear stress (CRSS) values that form the basis of a phenomenological description of plasticity, 2) enhancing effective metric selection for slip transfer across GBs, and 3) improving the understanding of the kinematics of the phase transformation—an important thermo-mechanical treatment that strongly influences the microstructure for many hexagonal engineering alloys such as Ti and Zr alloys.The first part of the present work is to quantify the uncertainty of initial CRSS values determined from Inverse indentation analysis (IIA). This approach optimizes the adjustable parameters in a chosen constitutive description of crystal plasticity until the load–depth response and the residual surface topography match between real and simulated nanoindentation(s) into a particular grain. IIA was evaluated for hexagonal pure Ti (CP-Ti) and two Ti alloys (Ti-3Al-2.5V and Ti-6Al-4V) at different temperatures (ambient and 523 K) and is found to produce consistent CRSS values when the combined relative error is no more than 20 %.A novel approach to evaluate the effectiveness of slip transfer metrics (individually) and their combinations using a double-layer artificial neural network (ANN) is presented as the second part of the thesis. The considered metrics include the misorientation angle between two grains, m′αβ , SFα +SFβ, ∆bαβ, and some of their compounds. The accuracy of binary (slip transfer or not) classification reaches around 90 % based on data collected from pure Al oligocrystals deformed in tension, and it is around 80 % for tensile deformed polycrystalline Ti-5Al-2.5Sn samples. This approach extends the one- or two-dimensional projections formerly applied to analyze slip transfer and can be implemented into crystal plasticity model as an “intelligent” decision-maker for each individual slip–boundary interaction.Lastly, a method to calculate orientation and deformation gradient variants resulting from phase transformation between hexagonal α and body-centered cubic β phase is proposed based on a series of frame rotations and transformations. Furthermore, a cluster-based approach is presented to automate point-wise reconstruction of β orientations from α orientations in a large indexed area. This work will assist in analyzing research problems that often require historical information of the current microstructures, for instance, understanding variant selections during the α → β → α transformation. The proposed method will also facilitate the implementation of such transformation kinematics into continuum-based models as the deformation gradient that influences the transformation can be conveniently computed.
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Title: The influence of peer feedback on writing achievement and individual writing self-efficacy
Creator: Zellner, Andrea Lynn
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This study examined the influence of peer feedback and review on individual writing achievement and self-efficacy. Undergraduate first-year composition students engaged in normal instructional activities used the Eli Review program in order to conduct peer feedback and review sessions. Using the data collected from surveys and through the web-based peer review system Eli Review, the influence of giving and receiving writing feedback in peer review groups on both individual writing achievement...
Show moreThis study examined the influence of peer feedback and review on individual writing achievement and self-efficacy. Undergraduate first-year composition students engaged in normal instructional activities used the Eli Review program in order to conduct peer feedback and review sessions. Using the data collected from surveys and through the web-based peer review system Eli Review, the influence of giving and receiving writing feedback in peer review groups on both individual writing achievement and individual self-efficacy was modeled using a social-network analysis methodology. The findings showed that students did not improve over the course of the semester in achievement or self-efficacy. Additionally, social network analysis suggested a negative relationship between the quality of feedback received on writing achievement, while no relationship was found between the quality of feedback given on writing achievement and self-efficacy. The findings suggest that practitioners should focus on modeling the feedback cycle, specifically ways to incorporate feedback into the revision process. -- Abstract.
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Title: The integration of computational methods and nonlinear multiphoton multimodal microscopy imaging for the analysis of unstained human and animal tissues
Creator: Murashova, Gabrielle Alyse
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Nonlinear multiphoton multimodal microscopy (NMMM) used in biological imaging is a technique that explores the combinatorial use of different multiphoton signals, or modalities, to achieve contrast in stained and unstained biological tissues. NMMM is a nonlinear laser-matter interaction (LMI), which utilizes multiple photons at once (multiphoton processes, MP). The statistical probability of multiple photons arriving at a focal point at the same time is dependent on the two-photon absorption ...
Show moreNonlinear multiphoton multimodal microscopy (NMMM) used in biological imaging is a technique that explores the combinatorial use of different multiphoton signals, or modalities, to achieve contrast in stained and unstained biological tissues. NMMM is a nonlinear laser-matter interaction (LMI), which utilizes multiple photons at once (multiphoton processes, MP). The statistical probability of multiple photons arriving at a focal point at the same time is dependent on the two-photon absorption (TPA) cross-section of the molecule being studied and is incredibly difficult to satisfy using typical incoherent light, say from a light bulb. Therefore, the stimulated emission of coherent photons by pulsed lasers are used for NMMM applications in biomedical imaging and diagnostics.In this dissertation, I hypothesized that due to the near-IR wavelength of the Ytterbium(Yb)-fiber laser (1070 nm), the four MP-two-photon excited fluorescence (2PEF), second harmonic generation (SHG), three-photon excited fluorescence (3PEF) and third harmonic generation (THG), generated by focusing this ultrafast laser, will provide contrast to unstained tissues sufficient for augmenting current histological staining methods used in disease diagnostics. Additionally, I hypothesized that these NMMM images (NMMMIs) can benefit from computational methods to accurately separate their overlapping endogenous MP signals, as well as train a neural network for image classification to detect neoplastic, inflammatory, and healthy regions in the human oral mucosa. Chapter II of this dissertation explores the use of NMMM to study the effects of storage on donated red blood cells (RBCs) using non-invasive 2PEF and THG without breaching the blood storage bag. Unlike the lack of RBC fluorescence previously reported, we show that with two-photon (2P) excitation from an 800 nm source, and three-photon (3P) excitation from a 1060 nm source, there was sufficient fluorescent signal from hemoglobin as well as other endogenous fluorophores. Chapter III employs NMMM to establish the endogenous MP signals present in healthy excised and unstained mouse and Cynomolgus monkey retinas using 2PEF, 3PEF, SHG, and THG. We show the first epi-direction detected cross-section and depth-resolved images of unstained isolated retinas obtained using NMMM with an ultrafast fiber laser centered at 1070 nm and a 303038 fs pulse. Two spectrally and temporally distinct regions were shown; one from the nerve fiber layer (NFL) to the inner receptor layer (IRL), and one from the retinal pigmented epithelium (RPE) and choroid. Chapter IV focuses on the use of minimal NMMM signals from a 1070 nm Yb-fiber laser to match and augment H&E-like contrast in human oral squamous cell carcinoma (OSCC) biopsies. In addition to performing depth-resolved (DR) imaging directly from the paraffin block and matching H&E-like contrast, we showed how the combination of characteristic inflammatory 2PEF signals undetectable in H&E stained tissues and SHG signals from stromal collagen can be used to analytical distinguish healthy, mild and severe inflammatory, and neoplastic regions and determine neoplastic margins in a three-dimensional (3D) manner. Chapter V focuses on the use of computational methods to solve an inverse problem of the overlapping endogenous fluorescent and harmonic signals within mouse retinas. The least-squares fitting algorithm was most effective at accurately assigning photons from the NMMMIs to their source. This work, unlike commercial software, permits using custom signal source reference spectra from endogenous molecules, not from fluorescent tags and stains. Finally, Chapter VI explores the use of the OSCC images to train a neural network image classifier to achieve the overall goal of classifying the NMMMIs into three categories-healthy, inflammatory, and neoplastic. This work determined that even with a small dataset (< 215 images), the features present in NMMMIs in combination with tiling, transfer learning can train an image classifier to classify healthy, inflammatory, and neoplastic OSCC regions with 70% accuracy.My research successfully shows the potential of using NMMM in tandem with computational methods to augment current diagnostic protocols used by the health care system with the potential to improve patient outcomes as well as decrease pathology departmental costs. These results should facilitate the continued study and development of NMMM so that in the future, NMMM can be used for clinical applications.
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Title: The interacting influences of habitat context and predators on monarch butterfly (Danaus plexippus L.) oviposition and survival in agricultural landscapes
Creator: Myers, Andrew Thomas
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Monarch butterflies (Danaus plexippus L.) are among the most recognizable and beloved insect species in North America. However, concern about the long-term persistence of monarch populations has grown during recent years due to the declining overwintering aggregations of both the eastern and western population segments. One hypothesized driver of the decline of the eastern population segment is the reduction of milkweed host plants from agricultural landscapes through the use of herbicide...
Show moreMonarch butterflies (Danaus plexippus L.) are among the most recognizable and beloved insect species in North America. However, concern about the long-term persistence of monarch populations has grown during recent years due to the declining overwintering aggregations of both the eastern and western population segments. One hypothesized driver of the decline of the eastern population segment is the reduction of milkweed host plants from agricultural landscapes through the use of herbicide-tolerant row cropping systems. Proponents of this hypothesis reason that with access to fewer host plants, monarchs are not able to lay their full complements of eggs during their lifetimes, resulting in lower population growth rates during the summer breeding season in the core of the breeding range. This hypothesis has motivated research efforts to determine which species of milkweed attracts the greatest oviposition rates and where these plants can be positioned to maximize egg laying by monarchs. Here I propose that monarch conservation efforts would also benefit from increased knowledge regarding the impact of predators on monarch eggs and larvae, as boosting survival during early life stages could substantially increase monarch breeding productivity. I performed several field experiments to investigate how habitat context and interactions with predators influence monarch oviposition and predation pressure. Using sentinel milkweed host plants and monarch eggs placed in various habitat treatments, I found that monarchs exhibit oviposition habitat preferences that vary between corn and grasslands depending on the year. I also showed that monarch egg survival over 72 h varies by year, but can be as low as 10% in grasslands. These experiments demonstrate that numbers of eggs observed by previous weekly surveys of various habitats reflect both the effects of oviposition preferences and predation rates and that grasslands represent relatively risky monarch egg habitats. Next, I sought to determine which predators were responsible for monarch egg mortality in grasslands by video monitoring over 150 monarch eggs. I found that a diversity of predators consumed monarch eggs, with a plurality of eggs consumed by spiders and a majority of eggs consumed during nocturnal hours. Finally, I sought to determine how the presence of ants influences monarch oviposition patterns and how aphid presence and species on host plants shapes monarch interactions between ants and monarch neonates. I measured first instar survival at 96 h on plants infested with Myzocallis asclepiadis, Aphis asclepiadis, or no aphids and with and without ants excluded and found the lowest monarch survival on Myzocallis-infested plants , but this effect disappeared when ants were excluded. I also found that wild monarchs laid significantly more eggs on plants with ants excluded, indicating that monarchs avoid ovipositing on plants with ants. Taken together, these studies demonstrate that reducing predation pressure on monarchs during early life stages has the potential to serve as an effective way to increase monarch productivity on limited land space in agricultural areas and provides important information regarding how habitat context and interactions with predators and other arthropods interact to influence monarch oviposition patterns and egg and early larval survival. I interpret the results of these studies in the context of monarch conservation and make recommendations for further study.
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Title: The interaction between feature- and space-based attention
Creator: Ozsarfati, Gozde
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Although the separate effects of feature- and space-based attention are relatively well established, the conjoint effects of attending to both a location and a feature are under-investigated. I analyzed the literature and extracted three approaches that explain such conjoint effects, namely the independence, sensory gating, and boosting approaches. The three approaches have substantial supports and shortcomings, and the current study will investigate which of the three approaches provide the...
Show moreAlthough the separate effects of feature- and space-based attention are relatively well established, the conjoint effects of attending to both a location and a feature are under-investigated. I analyzed the literature and extracted three approaches that explain such conjoint effects, namely the independence, sensory gating, and boosting approaches. The three approaches have substantial supports and shortcomings, and the current study will investigate which of the three approaches provide the best prediction of behavioral performance. I conducted two experiments to investigate whether the interplay between feature- and space-based attention varied as a function of the elapsed time between the cue and the target onset. A space-feature combination cue directed attention to a target on which participants discriminated small changes in color saturation. Both the spatial and feature cues were partially valid, making it possible to assess the cueing effect. The time difference between the cue and the saturation change onsets was manipulated in fine steps. Experiment 1 showed that space- and feature-based attention had an interactive effect on performance, such that feature-based attention did not influence performance outside the focus of space-based attention regardless of the temporal asynchrony between the cue and target onset. Experiment 2 was conducted to determine which of the three approaches provided the best account for the interaction pattern by adding a spatially neutral condition. It showed that feature- and space-based attention influenced performance, yet feature-based attention could not influence the performance outside the focus of spatial attention regardless of the temporal asynchrony between the cue and target onset. Moreover, the effectiveness of feature-based attention was equivalent at the spatially valid and neutral locations. In conclusion, the findings resemble with the predictions of the sensory gating approach. While feature-based attention could operate at the attended location or under diffused spatial attention equally well, its effectiveness diminished outside the focus of spatial attention. Moreover, the spatial filter imposed on feature-based attention is more permeable than originally proposed by the sensory gating approach. Lastly, feature-based attention does not fully spread to an unattended location regardless of the time difference between the cue and target onsets.
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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: The life and death of bone : a regional approach to the interpretation of fragmented and culturally modified Oneota human remains
Creator: Geske, Nicole Lynne
Date: 2018
Collection: Electronic Theses & Dissertations
Description: This dissertation utilizes previously collected archaeological, mortuary, and osteological data from multiple village and mortuary sites attributed to the Midwest archaeological culture known as Oneota (AD 900-1700). Isolated and fragmented human remains are commonly encountered in both mortuary and non-mortuary contexts, including burials, refuse and storage pits, and scattered throughout villages and middens. Many of these remains are also culturally modified through processes such as...
Show moreThis dissertation utilizes previously collected archaeological, mortuary, and osteological data from multiple village and mortuary sites attributed to the Midwest archaeological culture known as Oneota (AD 900-1700). Isolated and fragmented human remains are commonly encountered in both mortuary and non-mortuary contexts, including burials, refuse and storage pits, and scattered throughout villages and middens. Many of these remains are also culturally modified through processes such as burning, incising, and polishing. Although research regarding these remains is limited, these deposits have been attributed to violence and/or trophies of war. Therefore, the primary objective of this research was to examine the presence of fragmented and culturally modified human remains at Oneota sites and to theorize their possible meaning(s). This also included an evaluation of previous conclusions of violence. A secondary objective of this dissertation was to assess if published and previously collected data could be used to answer new research questions. Using spatial and correspondence analyses, this dissertation demonstrates patterning in the presence and location of culturally modified human remains. A contextual approach, as well as a theoretical framework that views the body as dividual and partible, were also used to demonstrate how human remains can become fragmented and isolated. Finally, ethnographies of the Winnebago (Ho-Chunk) and Ioway were used to find historical links between past and historic practices. This dissertation demonstrates a preference for cranial and long bone elements for fragmentation, as well as cultural modification. The choice of cranial elements is tied to the concept of the location of the soul, while the act of cultural modification is a transformation to either enhance or erase previously identities. Due to the degree of fragmentation, it cannot be precisely determined who specifically was used for this treatment. It is argued that these remains represent an aspect of the Oneota mortuary program that has not regularly been included in previous analyses.Multiple difficulties in data collection and analysis were encountered, primarily for data regarding fragmented and isolated human remains. Several varying treatments for isolated human remains were noted, leading to difficulty in their analysis and interpretation. Due to this difficulty, suggestions for future data collection for isolated human remains are provided.
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Title: The limits of sympathy : professional philanthropy and detachment in narrative, 1869-1914
Creator: Beard, Erin Elizabeth
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The Limits of Sympathy intervenes in the scholarly conversation surrounding the relationship between philanthropic reform and the novel as well as the role of women in philanthropic work during late Victorian England. Importantly, this project brings archival texts, such as the philanthropic case reports of the Charity Organisation Society, into the conversation in order to demonstrate how the professionalization of philanthropy eliminated the role of sympathy in philanthropic work and...
Show moreThe Limits of Sympathy intervenes in the scholarly conversation surrounding the relationship between philanthropic reform and the novel as well as the role of women in philanthropic work during late Victorian England. Importantly, this project brings archival texts, such as the philanthropic case reports of the Charity Organisation Society, into the conversation in order to demonstrate how the professionalization of philanthropy eliminated the role of sympathy in philanthropic work and narrative. Where philanthropic texts created new narrative forms to grapple with the New Poor Laws and the changing urban environment of late Victorian London, novels by George Eliot, Walter Besant, H. G. Wells, Edith Johnstone, and Isabella Ford considered how the adoption of professionalized, distanced discourse affected women's perception of and participation in philanthropic work. These novels demonstrate how our current critical reliance on sympathy as a way to mediate the relationship between philanthropic and poor characters, as well as between reader and novel, no longer works within the context of professionalized philanthropy. -- Abstract.
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Title: The meaning of teaching mathematics : teacher positionings as embedded in algebra teachers' guides
Creator: Suh, Heejoo
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Teacher educators have been examining the professional status of teaching, including defining central practices of teaching, comparing teaching to other professions, and understanding teachers’ own perspective via interviews, surveys, and observations. The present study intends to contribute to the discussion by examining the meaning of teaching as reflected in teachers’ guides. I chose to examine teachers’ guides because they are known to have impact on teachers. Being a resource that is...
Show moreTeacher educators have been examining the professional status of teaching, including defining central practices of teaching, comparing teaching to other professions, and understanding teachers’ own perspective via interviews, surveys, and observations. The present study intends to contribute to the discussion by examining the meaning of teaching as reflected in teachers’ guides. I chose to examine teachers’ guides because they are known to have impact on teachers. Being a resource that is close to teachers’ everyday practices, curriculum materials inspire teachers with what they could do in their classroom. Educators intending large-scale educational reform pay attention to curriculum materials. Careful use of linguistic features therein could enhance thus further support teachers’ guides in effective communication with teachers.I investigated four 8 th grade Algebra teachers’ guides - TG, selectively chosen to represent variety. Drawing on positioning theory, I observed positionings regularly appearing in each of those four. Then I turned to idiosyncratically-observable positionings. Two research questions sought understanding of what teaching mathematics entails as presented in the TGs, hence how each guide constructs teaching mathematics. Last, I examined the guides’ linguistic features. This was for understanding the degree of teacher professional judgment acknowledged by the guides.My results indicated that, as constructed by each guide, teaching mathematics does not differ much across the guides. Those guides presented various types of knowledge as entailed in teaching mathematics. Compared to aspects on teacher professionalism in the literature, the guides occasionally addressed teacher research, interaction with colleagues, utilizing knowledge, and acknowledging uncertainty. In addressing these aspects, the guides in most cases did so with insufficient support. Examining idiosyncratic positionings, I found two types: i) positionings occurred idiosyncratic only, and ii) positionings occurred idiosyncratically in addition to their regular appearance. The latter can be classified into two types: a) one that succeeds the context of the communication actions associated with the general positioning, and b) one dissociated from the context. My linguistic examination of the guides suggested that they varied in their use of voice. Some are more directive, others are more suggestive, indicating different levels of acknowledgement of teachers’ professional judgment. In this dissertation’s last chapter, I present ways in which this study contributes to understanding of curriculum materials and of teacher professionalism. I end this dissertation with implications for curriculum authors, teachers, teacher educators, and researchers.
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Title: The moralization matrix : a tool for school improvement
Creator: Lavender, Amieris B.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Over the past twenty years, education reform efforts aimed at teachers, students, principals, curriculum, and school facilities have targeted urban schools. Yet, many social policies fail. Education reforms are more likely to succeed when the culture of an initiative is congruent with the culture of a school. Currently, there is no way for stakeholders to decide if the socio-cultural realities of their school and a policy's design are well matched. This single-site case study tested whether a...
Show moreOver the past twenty years, education reform efforts aimed at teachers, students, principals, curriculum, and school facilities have targeted urban schools. Yet, many social policies fail. Education reforms are more likely to succeed when the culture of an initiative is congruent with the culture of a school. Currently, there is no way for stakeholders to decide if the socio-cultural realities of their school and a policy's design are well matched. This single-site case study tested whether a quantitative measure could accurately assess a school's culture. To do so, interviews with school personnel and staff observations were conducted and compared to the assessment results. It was found that survey data was congruent with the data collected qualitatively from staff members. These findings hold promise for the future development and implementation of programs, as well as, principal leadership practice.
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Title: The needs of nutrition and physical activity education for caregivers of Michigan migrant and seasonal farmworker children
Creator: Feighner, Amanda Rose
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "Migrant and seasonal farmworker (MSFW) children have high rates of overweight and obesity, which can lead to health issues through childhood and adulthood. Caregivers of young children have the ability to influence environment and role model behaviors related to nutrition and physical activity for children. Migrant and Seasonal Head Start (MSHS) programs serve young MSFW children by providing a venue for nutrition and physical activity promotion for extended hours with the ultimate goal of...
Show more"Migrant and seasonal farmworker (MSFW) children have high rates of overweight and obesity, which can lead to health issues through childhood and adulthood. Caregivers of young children have the ability to influence environment and role model behaviors related to nutrition and physical activity for children. Migrant and Seasonal Head Start (MSHS) programs serve young MSFW children by providing a venue for nutrition and physical activity promotion for extended hours with the ultimate goal of helping at-risk children succeed. We also reported high prevalence of obesity and overweight among MSHS children's caregivers, i.e., parents and MSHS staff. This situation provides important educational opportunities to apply social cognitive theory and policy, systems, and environmental change approaches in order to meet the needs of caregivers (parents and MSHS staff) who can become competent to practice healthy lifestyles for family and MSHS children. In developing nutrition and physical activity education programs targeting caregivers of Michigan MSHS children, this study aimed to identify the perceived needs for content, facilitators and barriers to participating such programs. Of 17 total MSHS centers in Michigan, five of the largest sites were selected for recruitment of MSHS program parents and staff. Twelve focus groups were conducted between July and September 2016 with staff (n = 27), parents (n = 33), and MSHS center directors (n = 13). Focus groups with the consented parents were conducted at MSHS sites in Spanish, with staff in English, and with directors at a central office meeting. Using censuses coding among three researchers, key themes were identified. Quantitative surveys were conducted in parallel to this qualitative study with parents (n = 135) at nine centers and staff (n = 280) at all 17 MSHS centers in Michigan between July-August 2016.We found that desired content for programs included basic nutrition knowledge, cooking and meal planning, physical activity, and budgeting. Facilitators and barriers to participation in a new nutrition and physical activity program included program structure, financial support, education format, and motivation factors. Nutrition education interventions for parents and staff need to be combined with efforts to improve their children's health. We generated key information that can be used in planning future interventions for caregivers of MSHS children. Caregivers who are competent in nutrition and physical activity knowledge may be able to influence the environment and behaviors of their children and MSHS community to promote healthy lifestyles."--Page ii.
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Title: The nutrient-responsive regulation of cell division and quiescence in Chlamydomonas reinhardtii
Creator: Takeuchi, Tomomi
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Faced with adverse conditions, nearly all cells are able to cease energy-costly processes associated with the cell division cycle and enter a reversible alternative state known as quiescence (G0). In the green microalga Chlamydomonas reinhardtii, the entry into and exit from such a non-dividing state is mediated in response to the availability of nutrients, such as nitrogen (N). Following N starvation, a whole-sale reprogramming of intracellular processes takes place in order to maximize the...
Show moreFaced with adverse conditions, nearly all cells are able to cease energy-costly processes associated with the cell division cycle and enter a reversible alternative state known as quiescence (G0). In the green microalga Chlamydomonas reinhardtii, the entry into and exit from such a non-dividing state is mediated in response to the availability of nutrients, such as nitrogen (N). Following N starvation, a whole-sale reprogramming of intracellular processes takes place in order to maximize the chances of survival, including the repression of cell cycle-related genes, the multi-level downregulation of photosynthesis, the induction of autophagy, and the diversion of carbon (C) towards triacylglycerols (TAG).One protein implicated in the regulation of nutrient-responsive quiescence-associated transcriptomic programs in Chlamydomonas is Compromised Hydrolysis of TAG 7 (CHT7). The CHT7 protein contains cysteine-rich motifs that are often collectively referred to as the CXC domain, which is widely known for its ability to bind DNA in a sequence-specific manner in animals. A number of CXC domain-containing proteins in both animals and plants have been identified as core constituents of transcriptional regulatory complexes termed DREAM (DP, RB, E2F and Myb-MuvB) complexes, which act to coordinate cell cycle-related gene expression in response to various signals present during quiescence, cell proliferation and differentiation, and development. Through the generation of newly introgressed cell-walled lines and the detailed examination of the cht7 mutant at cellular levels, my dissertation work identified novel quiescence-related transcriptional defects in cht7 during N starvation, including derepression of DNAmetabolism and cell cycle-related genes and downregulation of oxidoreductase- and nutrient transporter-encoding genes. Largely due to their inability to repress S/M (DNA synthesis/mitosis) phase-specific gene expression, the cht7 cells were unable to properly arrest nuclear replication and cell division following N removal. The loss of viability during N starvation and the abortive divisions during N refeeding were identified as causal for the observed delay in resuming growth and the reduction in colony formation in cht7 following N resupply.The homolog of the retinoblastoma tumor suppressor (RB) protein in Chlamydomonas, MAT3, and CHT7 were shown to coimmunoprecipitated together during N-replete synchronized growth and following N deprivation, and several phosphorylated isoforms of CHT7 were identified under these conditions. Despite the presence of the presumed DNA-binding function of the CXC domain in CHT7, the largely disordered C-terminal half of CHT7 with predicted protein-binding domains, and not the proposed CXC DNA-binding domain, was essential for the ability of CHT7 to form stable complexes, and to restore the cellular phenotypes and transcript levels back to wild-type levels in the cht7 mutant. Taken together, while the mechanism of CHT7 function likely differs from that of canonical CXC domain proteins, CHT7 is necessary for the establishment of an effective quiescent state and thus, the nutrient-mediated life-cycle transitions in Chlamydomonas. A better understanding of how the cell division cycle is regulated in response to nutrient scarcity may improve the prospects of biofuels and biomass production in microalgae.
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Title: The ones who need the most : race, ability, and restorative justice in an urban school
Creator: Presberry, Cierra Brittney
Date: 2020
Collection: Electronic Theses & Dissertations
Description: This dissertation examines how the intersection of race and ability impact an urban school's implementation of restorative justice. Because restorative justice can ideally be used in any setting with any group of people, its generalization often overlooks exceptionally vulnerable or traditionally silenced populations. As such, using Critical Race Theory and related frameworks such as Dis/ability Critical Race Studies and Critical Race Parenting, this work specifically highlights how Black...
Show moreThis dissertation examines how the intersection of race and ability impact an urban school's implementation of restorative justice. Because restorative justice can ideally be used in any setting with any group of people, its generalization often overlooks exceptionally vulnerable or traditionally silenced populations. As such, using Critical Race Theory and related frameworks such as Dis/ability Critical Race Studies and Critical Race Parenting, this work specifically highlights how Black students with disabilities, their teachers, and their parents are impacted by, and engaged with restorative justice at school. This dissertation is written in the form of three papers. In paper one, I conduct an interview study in order to examine insights from special education teachers about their role in using restorative justice and how it impacts their students, particularly in terms of how race and ability are pivotal factors. In paper two, I conceptualize restorative justice literacies. This entails an examination of how reading, writing, and speaking play a role in how marginalized populations are able to understand and participate in restorative justice practices. This research took place in the form of case study, with student observation, interviews, and document analysis being primary sources of data. Finally, in paper three, I analyze the perspectives of the parents of students from paper three regarding their engagement with restorative justice. Findings from my research highlight aspects of the experiences and needs of students with disabilities that have yet to be addressed within literature on restorative justice, and has positive implications for the ways that school communities can better understand and accommodate students with disabilities within both general and special education settings.
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Title: The owner's role in contractor safety management : a pattern language
Creator: Hansmann, Zachary David
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "Construction is a dangerous industry that historically accounts for a disproportionate number of injuries and illnesses. Despite improvements in the last few decades, this trend of injuries compared to other industries persists year over year. The owner has been shown to be a pivotal member of construction projects with the ability to improve contractor safety performance. It has also been shown that owners ultimately reap the benefits of these improvements in safety performance, yet buyers...
Show more"Construction is a dangerous industry that historically accounts for a disproportionate number of injuries and illnesses. Despite improvements in the last few decades, this trend of injuries compared to other industries persists year over year. The owner has been shown to be a pivotal member of construction projects with the ability to improve contractor safety performance. It has also been shown that owners ultimately reap the benefits of these improvements in safety performance, yet buyers of construction are still inconsistent in their focus on the importance of construction safety.Previous research studied owners whose contractors exhibited exemplary contractor safety performance to establish recommended practices. These studies have not considered the reality owners must operate in, including what bad practices owners may unintentionally participate in that lead to an increase in problems and ultimately liability for the owner.This research investigated how an owner should interact with independent contractors when it comes to safety management. To do this, pattern language and grounded theory methods were combined to examine the practices of owners, the preferences of safety professionals, and the existing academic recommendations to both determine the state of the industry and to identify the aspirational practices owners may seek to employ.This study found that owner practices do not align with the practices identified in the literature, and that both owners and academics need to expand their perspective to maximize any potential improvement. Thirty-six positive practices were identified across four major categories, including communication, site safety planning, contractual control, and owner involvement. Further, eleven potentially negative practices were also identified that often led to owners unknowingly and needlessly taking responsibility and, by extension, shouldering liability for their contractors. Finally, the forces that an owner must consider when balancing competing priorities were identified to help understand the often conflicting priorities that shape owner behavior.Ultimately, the owner's role in construction safety is driven by their project risk, risk tolerance, capability, resources, and other characteristics specific to that owner, at that time, and in that space. Each situation remains a fact-intensive occurrence that deserves careful consideration and action. The work practices, identified in this research as patterns, allow owners to understand the recommended practices of the industry and allow each to make a careful assessment of their best course of action. Owners who understand the implication of their actions, as well as the impact of each related practice, will make decisions that more appropriately fit their needs.Future work on this topic should take the practices laid out in this research and begin to assess the impact of each practice on the balance of the remaining practices of the pattern language. With this information, owners could identify their best course of action in a quantitative way. Likewise, research in this area must reevaluate prior findings in the light of the current environment in which these owners work. Some practices and solutions suggested in existing work are untenable in many owner situations. This is evident from the significant difference in the practices recommended by academia and the current practices of owners."--Pages ii-iii.
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Title: The paradox of asymmetric competition : asymmetric rivalry and asymmetric competitive analysis
Creator: Manjeshwar, Sonia
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The literature on asymmetric competition has largely portrayed asymmetry to be a competitive advantage. However, this assertion has been made on the basis of studies that assume perfect rationality and ignore cognitive limitations of firms. The salience of assuming cognitive limitations becomes evident when we decompose the concept of asymmetric competition into its individual components of interfirm rivalry and competitive analysis (Chen 1996). At the action level of interfirm rivalry,...
Show more"The literature on asymmetric competition has largely portrayed asymmetry to be a competitive advantage. However, this assertion has been made on the basis of studies that assume perfect rationality and ignore cognitive limitations of firms. The salience of assuming cognitive limitations becomes evident when we decompose the concept of asymmetric competition into its individual components of interfirm rivalry and competitive analysis (Chen 1996). At the action level of interfirm rivalry, asymmetry captures the one-sided, actionresponse dynamic between competing firms, and denotes the competitive advantage of attacking your rivals with impunity. Seen from a focal firm's point of view, asymmetry at the cognitive level of competitive analysis implies a dangerous situation, indicating the firm's inability to recognize or respond to competitive threats from outwardly insignificant competitors (Chen 1996; Desarbo, Grewal, and Wind 2006). The purpose of this study is to develop a theoretical understanding of the paradoxical phenomenon of asymmetric competition and provide insight into why such contradicting outcomes occur. Furthermore, we consider that competitive experience is embedded within the larger context of institutional norms, political systems, and social network structures (Desarbo, Grewal and Wind 2006; Grewal and Dharwadkar 2002). Using data from 41 publicly traded firms in the U.S. retail industry observed over a ten-year period (2003-2012), we examined the paradoxical nature of asymmetric competition. Our results strongly suggest that while strategic adaptations to a context's logic of competition lead to the favorable consequence of asymmetric rivalry, some of the same strategic adaptations lead to the adverse effect of asymmetric competitive analysis. We found that firms' defensive manipulation of political logics in the form of money spent on campaign finance and lobbying is significantly and positively related to the focal firm's ability to carry out greater number of competitive actions relative to rivals. However, defensive manipulation of political logics was also found to be significantly and positively related to the focal firm's market share erosion, indicating impaired awareness that characterizes asymmetric competitive analysis. Similarly, we found that when firms had a hierarchical distribution of positional embeddedness among their key decision-makers, they were able to perform more competitive actions compared to their rivals. However, we also found that a hierarchical distribution of positional embeddedness among key decision-makers to also be positively and significantly related to the firms engaging in a narrow repertoire of competitive actions, indicating exploitative behaviors associated with asymmetric competitive analysis. Our results bear important implications for future research, managerial practices, and public policy, on a topic that has been largely overlooked in the marketing strategy literature."--Pages ii-iii.
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Title: The patriot and the traitor : defending your collective face in front of co-nationals and foreigners
Creator: Zhu, Yi (College teacher)
Date: 2019
Collection: Electronic Theses & Dissertations
Description: The current between-subjects study investigated how participants from two cultural groups (100 American domestic students and 115 Chinese international students) deal with threats to their collective face elicited from a critic who is either an ingroup member, an outgroup member, or an identity-unspecified member in an intercultural-communication context with a laboratory experimental design. Chinese students reported higher collective face concerns and lower liking towards a person who...
Show moreThe current between-subjects study investigated how participants from two cultural groups (100 American domestic students and 115 Chinese international students) deal with threats to their collective face elicited from a critic who is either an ingroup member, an outgroup member, or an identity-unspecified member in an intercultural-communication context with a laboratory experimental design. Chinese students reported higher collective face concerns and lower liking towards a person who criticized their collective face compared with Americans. While encountering criticism targeting their countries, Chinese felt higher discomfort feelings compared with Americans. Chinese participants' discomfort feelings in the ingroup-critic condition were more influenced by their collective face concerns compared with Americans in the same condition. The practical and methodological implications of this study were also discussed.
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Title: The political determinants of agricultural policy in sub-Saharan Africa
Creator: Lewis, Dominique Helena
Date: 2017
Collection: Electronic Theses & Dissertations
Description: My thesis investigates the political determinants of agricultural policy in sub-Saharan Africa, but my work also has implications for broader questions of development economics and public policy formation. Agricultural producers are vital engines of economic development in this region of the African continent. For this reason, policies that enhance the stability and growth of agricultural production are among the most crucial to development more generally. Yet across much of sub-Saharan...
Show moreMy thesis investigates the political determinants of agricultural policy in sub-Saharan Africa, but my work also has implications for broader questions of development economics and public policy formation. Agricultural producers are vital engines of economic development in this region of the African continent. For this reason, policies that enhance the stability and growth of agricultural production are among the most crucial to development more generally. Yet across much of sub-Saharan Africa, pricing policies often work to disadvantage agricultural production, while governmental spending on agricultural research and development remains low. Even more puzzling is the fact that rural constituents uniformly support incumbent policy makers at higher rates than their urban counterparts, even in the face of policies that are manifestly antithetical to their interests. The answer to this puzzle lies in the importance of collective action to policy creation and change and, in particular, how institutional constraints and other such barriers to collective action shape representation in the agricultural sector. Utilizing both the cross-country and temporal variation in policy environments and outputs, I show that institutional contexts which facilitate collective action are associated with pro-agricultural policies, including lower taxes on agricultural products and higher national-level spending on agricultural R&D. Such contexts -- which include institutional protections for civil liberties and higher levels of electoral competition -- allow marginalized groups such as the rural poor to mobilize more effectively, which in turn result in policies more favorable to their interests. Such policies are further facilitated by sector-specific features and practices which enhance mobilization, typically by decreasing the associated costs of such actions. My findings underscore the importance of the broader political and institutional forms on agricultural policy. That is to say, my analysis demonstrates that prescriptions and suggestions for reforms that are designed to enhance agricultural development should not and cannot be limited to those with agriculture as their sole and central focus.
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Title: The power paradox : intimacy and masculinity in American football
Creator: James, Riley
Date: 2019
Collection: Electronic Theses & Dissertations
Description: This thesis examines how intimacy-both physical and emotional-in American football affects masculinity. This research is important because it questions the role of masculinity in a sport considered the most popular in terms of participation, attendance at games, and broadcast viewership (Miaschi, 2017). Theories such as hegemonic masculinity theory and inclusive masculinity theory are used to explain how masculinity is constructed through football. Using naturalistic observation, interviews...
Show moreThis thesis examines how intimacy-both physical and emotional-in American football affects masculinity. This research is important because it questions the role of masculinity in a sport considered the most popular in terms of participation, attendance at games, and broadcast viewership (Miaschi, 2017). Theories such as hegemonic masculinity theory and inclusive masculinity theory are used to explain how masculinity is constructed through football. Using naturalistic observation, interviews with seven Michigan State University (MSU) football players, and an analysis of photographs, I found these football players have more intimate relationships with other players on their team when compared to relationships they have with other men outside their sport. Some surprises I found during interviews was that injury during football is not treated as harshly as it once was and one player views being emotional as an important part of being a man. I visually present the intimate aspects of football I witnessed in photographs I created as an employee of Big Ten Network during MSU football games during the 2017 and 2018 seasons, and I offer my analysis of intimacy and masculinity in this sport that includes and explains the meaning behind the power paradox.
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Title: The quest for active media models : a self-consistent framework for simulating wave propagation in nonlinear systems
Creator: Glosser, Connor Adrian
Date: 2018
Collection: Electronic Theses & Dissertations
Description: This work presents new approaches to simulations of active media at the level of individual particles. Active systems contain internal, nonlinear, processes beyond those of simple scattering systems; thus these new models afford high degrees of fidelity in exploring the underlying physics without recourse to continuum or spatially-averaged approximations.First, I examine the dynamics of microspheres set into motion by ambient acoustic radiation in a fluid described by potential flow in the...
Show moreThis work presents new approaches to simulations of active media at the level of individual particles. Active systems contain internal, nonlinear, processes beyond those of simple scattering systems; thus these new models afford high degrees of fidelity in exploring the underlying physics without recourse to continuum or spatially-averaged approximations.First, I examine the dynamics of microspheres set into motion by ambient acoustic radiation in a fluid described by potential flow in the long-wavelength limit. Variations in the local surface pressure caused by scattering from each microsphere set each microsphere into motion following Newton’s second law. By expanding this pressure in terms of spherical harmonics—natural eigenfunctions of the unretarded radiation kernel—I recover an analytic description of the force on individual microspheres due to an incident waveform. High-order numerical integrations then relate the surface potential on one microsphere to the surface pressure on the others, thereby coupling the microspheres’ trajectories. These simulations predict a dominant translational effect along the direction of propagation of the incident waveform, though they also reveal significant dipolar interactions between microspheres that produce secondary expansions and contractions of the collective microsphere system.Extending my approach from acoustic to electromagnetic systems, I apply it to a collection of quantum dots: “artificial” two-level atoms with a size-dependent energy structure. The optical Maxwell-Bloch equations give the evolution of quantum dots under the influence of electromagnetic fields; this evolution then produces secondary radiation that couples a collection of quantum dots together. In my computational model, I castmy secondary electromagnetic fields in terms of a point-to-point integral operator that accurately recovers both near- and far-field effects. These fields, then, drive a set of implicitly coupled Bloch equations (solved with an exponentially-fitted predictor/corrector scheme) to give the dynamics of the system as a whole. In ensembles of up to 10 000 quantum dots, my model predicts synchronized multiplets of particles that exchange energy, quantum dots that dynamically couple to screen the effect of incident external radiation, localization of the polarization due to randomness and interactions, as well as wavelength-scale regionsof enhanced and suppressed polarization.The remainder of the work uses the same physical quantum dot system while moving towards efficient computer-aided device design. I detail an improved propagation algorithm to reduce the time and space complexity of the simulation dramatically, thereby facilitating rapid analysis of promising device structures. The algorithm makes use of physical and numerical approximations to effect large-scale calculations in reasonable CPU time. A rotating-frame approximation removes high-frequency components in the evolution of the system while simultaneously preserving accurate interference phenomena in space,thereby affording far larger simulation timesteps. Additionally, projecting the source current distribution onto a regular spatial grid makes use of a low-rank approximation to the field propagator to communicate radiation information between distant groups of particles via fast Fourier transforms in a manner reminiscent of fast multipole methods.
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Title: The regiments : cultural histories of Zulu masculinities and gender formation in South Africa, 1816-2018
Creator: Timbs, Elizabeth H.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "This dissertation reconstructs aspects of the history of Zulu martial heritage through the prism of the amabutho (regiments, age-grades) in KwaZulu-Natal, South Africa, from the era of Shaka Zulu (ca. 1816) to the present. Based on archival research and oral history interviews, this study argues that despite being outlawed by the British colonial regime in 1879, Zulu chiefs continued to form amabutho, but for different purposes. Regiments became youth structures for commercial labor...
Show more"This dissertation reconstructs aspects of the history of Zulu martial heritage through the prism of the amabutho (regiments, age-grades) in KwaZulu-Natal, South Africa, from the era of Shaka Zulu (ca. 1816) to the present. Based on archival research and oral history interviews, this study argues that despite being outlawed by the British colonial regime in 1879, Zulu chiefs continued to form amabutho, but for different purposes. Regiments became youth structures for commercial labor recruitment and British military conscription; they enabled indigenous leaders to access martial discourse and metaphors for political mobilization; expressed cultural forms of resistance to state racism; and nurtured the sustenance of Zulu identities in a changing South Africa. Exploring the amabutho's links to the Zulu monarchy also helps to shed light on the evolving role and status of the Zulu Royal House. While both the white-run Natal and Union governments feared the influence that Shaka's successors held among Zulu-speaking Africans, the authorities also relied on Paramount Chief Solomon to recruit black volunteers from Natal and Zululand for World War I. In the apartheid era (1948-1994), the invocation of the Zulu nation's warrior legacy endured. As migrant laborers, Zulu men recreated their martial identities and manifestations of the amabutho became more abstract, emerging in society, culture, and politics in unexpected ways. As the struggle against apartheid intensified, the continued relevance of this martial heritage mobilized Zulu communities, bringing them in conflict with first the African National Congress and later the United Democratic Front. In the post-apartheid period (1994-present), the rhetoric, symbolism, and practices of Zulu regiments continues to resonate and evolve. In the case of "high politics," Zulu political leaders turn to martial metaphors to engender support, while, on the ground, local authorities throughout the province struggle to maintain the traditions that give these metaphors meaning. The historiographical significance of this dissertation is threefold. First, it extends earlier studies to consider Zulu martial masculinity over two centuries. Second, it uncovers how amabutho shaped, and have been shaped by, white anxieties about Zulu men's "violent potential" as well as a need for cheap labor. Third, this dissertation reconsiders the shifting role of chiefs and kings in South Africa since 1800."--Pages ii-iii.
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