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Title: Volumes, determinants, and meridian lengths of hyperbolic links
Creator: Burton, Stephan D., 1987-
Date: 2017
Collection: Electronic Theses & Dissertations
Description: We study relationships between link diagrams and link invariants arising from hyperbolic geometry. The volume density of a hyperbolic link K is defined to be the ratio of the hyperbolic volume of K to the crossing number of K. We show that there are sequences of non-alternating links with volume density approaching v_8, where v_8 is the volume of the regular ideal hyperbolic octahedron. We show that the set of volume densities is dense in [0,v_8]. The determinant density of a link K is 2 pi...
Show moreWe study relationships between link diagrams and link invariants arising from hyperbolic geometry. The volume density of a hyperbolic link K is defined to be the ratio of the hyperbolic volume of K to the crossing number of K. We show that there are sequences of non-alternating links with volume density approaching v_8, where v_8 is the volume of the regular ideal hyperbolic octahedron. We show that the set of volume densities is dense in [0,v_8]. The determinant density of a link K is 2 pi log det(K)/c(K). We prove that the closure of the set of determinant densities contains the set [0, v_8]. We examine the conjecture, due to Champanerkar, Kofman, and Purcell that vol(K) < 2 pi log det (K) for alternating hyperbolic links, where vol(K) = vol(S^3\ K) is the hyperbolic volume and det(K) is the determinant of K. We prove that the conjecture holds for 2-bridge links, alternating 3-braids, and various other infinite families. We show the conjecture holds for highly twisted links and quantify this by showing the conjecture holds when the crossing number of K exceeds some function of the twist number of K.We derive bounds on the length of the meridian and the cusp volumeof hyperbolic knots in terms of the topology of essential surfaces spanned by the knot.We provide an algorithmically checkable criterion that guarantees that the meridian length of a hyperbolic knot is below a given bound.As applications we find knot diagrammatic upper bounds on the meridian length and the cusp volume of hyperbolic adequate knots and we obtain new large families of knots withmeridian lengths bounded above by four. We also discuss applications of our results to Dehn surgery.
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Title: Using cover crops in wheat-corn rotations to provide forage while improving soil
Creator: Gerdes, Sabra Lynn
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The time window after wheat harvest in a wheat (Triticum aestivum L.)- corn (Zea mays L.) rotation could be used to grow cover crops (CC) to provide forage while protecting soil from erosion. Field experiments were initiated in East Lansing, MI to determine the consequences of partial removal of CC biomass on soil improvement and crop yield and quality. Soft red winter wheat ('Hopewell' 03360336and 03360336'Red 03360336Dragon') was planted in October of 2013 and 2014 and harvested in July...
Show more"The time window after wheat harvest in a wheat (Triticum aestivum L.)- corn (Zea mays L.) rotation could be used to grow cover crops (CC) to provide forage while protecting soil from erosion. Field experiments were initiated in East Lansing, MI to determine the consequences of partial removal of CC biomass on soil improvement and crop yield and quality. Soft red winter wheat ('Hopewell' 03360336and 03360336'Red 03360336Dragon') was planted in October of 2013 and 2014 and harvested in July 2014 and 2015. Cover crops included: frost-seeded red clover, and summer-seeded alfalfa, cowpea, sunn hemp, radish, oat/field pea mixture, sudangrass, sorghum x sudangrass, and teffgrass. Half of each CC plot was mechanically harvested eight weeks after planting. Harvested forage dry matter yield was greatest for red clover (4.3 Mg ha-1 ); oat-pea mix (2.5 Mg ha-1 ), sudangrass/sudex (1.8 Mg ha-1 ) and radish (1.2 Mg ha-1 ) (P < 0.01) yielded less. Corn grain yield harvested in October averaged 13.7 Mg ha-1 and did not differ across CC species or forage harvest treatment (P > 0.05). Harvesting forage reduced total N removal (TNR) in subsequent corn for red clover only; harvesting forage did not affect TNR after any other CC (CC x harvest interaction, P < 0.05). In the harvested system, TNR did not differ (P > 0.05) between for any CC, but unharvested RCL (374 kg N ha-1 ) had greater (P < 0.01) TNR than oat-pea mix (338 kg N ha-1 ). There were no differences among treatments for soil permanganate oxidizable carbon POXC (P > 0.05). Harvesting cover crops for forage after winter wheat harvest in Michigan can give harvestable forage and acceptable nutritive value."--Page ii.
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Title: Internationalizing graduate education through education abroad : the pedagogy of short-term, faculty-led, education abroad experiences
Creator: Loebick, Karla
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The purpose of this study was to develop understanding of the perspectives of faculty members as leaders of short-term, faculty-led, education abroad at the graduate level ... " Abstract.

Title: Agency in context : a phenomenological study of Chinese college lLearners' intercultural engagement with expatriate instructors
Creator: Larson, Jay B.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "As China increasingly internationalizes its higher education system, growing numbers of Chinese learners and expatriate instructors meet in the classroom, engaging one another from their disparate cultural and pedagogical standpoints. Despite its widespread occurrence, the phenomenon of Chinese learners and Western instructors engaging one another in pedagogically and culturally Chinese institutions is largely neglected in research. Scholarly literature on Chinese learners is dominated by...
Show more"As China increasingly internationalizes its higher education system, growing numbers of Chinese learners and expatriate instructors meet in the classroom, engaging one another from their disparate cultural and pedagogical standpoints. Despite its widespread occurrence, the phenomenon of Chinese learners and Western instructors engaging one another in pedagogically and culturally Chinese institutions is largely neglected in research. Scholarly literature on Chinese learners is dominated by studies of their experiences as international students on Western campuses. In Chinese environments, authors most often examine perspectives of expatriate instructors on their cultural adjustments. The voice of the Chinese learner in China is rarely heard in research. In this study, I turned a phenomenological lens toward 17 Chinese learners' lived experiences of intercultural classroom engagement at China's Southwest University. Drawing on works of Hall (1997a, 1997b), Said (1978), and Simmel (1971), I devised a Progression Model of Intercultural Engagement to frame participants' evolving perceptions of expatriate instructors as culturally foreign Others. I focused my analysis of learners' perceptions through three overlapping areas of inquiry: (a) learners' sense-making processes and management of intercultural teaching and learning; (b) their perceptions of the expatriate instructor as a physical, social, and cultural presence; and, (c) perceptions of expatriate instructor's course design and teaching. I collected data over a two-month period at Southwest University through methods including classroom observations, Chinese language participant essays, and English language interviews. Findings revealed learners exercised ownership and agency in interpreting and managing intercultural engagement with their instructors. Participants expressed ownership of a perceived physically, linguistically, and academically Chinese environment. Within that environment, they initially characterized expatriate instructor by foreign-ness. Learners made further sense of intercultural experience by situating their instructors' foreign-ness in constructed social, pedagogical, linguistic, and cultural roles. These roles assigned purpose to the expatriate instructor's foreign presence, and framed the meanings learners constructed from intercultural engagement. Finally, participants interpreted their relationships with written and spoken English through engagement with expatriate instructors perceived as social, pedagogical, and cultural embodiments of language. In sum, findings indicate perceived cultural context of the environment, and senses of ownership and agency learners exercised in this environment. These findings contribute to the academic dialogue on intercultural teaching and learning, not only in Chinese institutional contexts, but anywhere knowledge construction must bridge cultural assumptions, epistemologies, and pedagogies. This study can inform further inquiry into international learners on Western campuses, multinational classes in education hubs, and Western learners studying abroad. I address these applications, and others, as I conclude this dissertation with recommendations for practice, and implications for research and theory."--Pages ii-iii.
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Title: Seeking or encountering news on the Web : the role of need for cognition and need to evaluate
Creator: Lee, Heysung
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Previous literature has dealt with news consumption patterns on the web, but not many attempts have done to clarify individual differences by focusing on a role of personality variables. This study suggests that high need for cognition will lead digital news consumers to actively seek out news websites to get political information, whereas low need for cognition will lead them to passively encounter political news on social media. The results of the online survey indicate that need for...
Show morePrevious literature has dealt with news consumption patterns on the web, but not many attempts have done to clarify individual differences by focusing on a role of personality variables. This study suggests that high need for cognition will lead digital news consumers to actively seek out news websites to get political information, whereas low need for cognition will lead them to passively encounter political news on social media. The results of the online survey indicate that need for cognition does not predict news consumption on the web, but only need to evaluate positively correlates to news website usage. Also, both variables positively correlate to active sharing and commenting on political information in social media, attention to political news, and political knowledge. -- Abstract.
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Title: Evaluating the conservation and agricultural applications of orchard nest boxes for a declining raptor
Creator: Shave, Megan Ellen
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Human activities over the past 50 years have caused changes in ecosystems that have led to gains in economic development at the cost of biodiversity loss and degradation of ecosystem services, the functions and processes of ecosystems that benefit human well being. For example, agricultural expansion and intensification has degraded wildlife habitat by removing sources of nesting and roosting cavities, particularly mature trees, which can negatively affect abundance and diversity of animal...
Show moreHuman activities over the past 50 years have caused changes in ecosystems that have led to gains in economic development at the cost of biodiversity loss and degradation of ecosystem services, the functions and processes of ecosystems that benefit human well being. For example, agricultural expansion and intensification has degraded wildlife habitat by removing sources of nesting and roosting cavities, particularly mature trees, which can negatively affect abundance and diversity of animal taxa that provide regulating ecosystem services, such as pest reduction. Many cavity-dependent species will use nest boxes in areas where natural cavities are scarce, thus nest boxes are an easily implemented landscape enhancement. In this dissertation, I drew from theoretical frameworks of population dynamics, foraging ecology, parental care, and predator-prey interactions to assess the potential benefits of nest boxes in terms of conservation of a declining raptor and enhancement of pest reduction services in a fruit-growing region. Although the American Kestrel (Falco sparverius) is the most common falcon in North America, multiple monitoring programs have detected significant and widespread population declines. While the causes of these declines at the continent-wide scale are not yet understood, at the local scale, many breeding kestrel populations are limited by availability of nest sites. In Chapter 1, I monitored 18 new nest boxes installed in cherry orchards (Prunus spp.) in northwestern Michigan and found that kestrels made nesting attempts in 100% of the boxes and showed high reproductive rates. Furthermore, models of daily survival rates for nests and brood size at fledging for successful nests indicated that kestrels were highly tolerant of both traditional monitoring techniques (opening the box) and newer camera technologies (a pole-mounted video camera and nest-box video cameras). In Chapter 2, I used roadside transect surveys and multi-season occupancy modeling to determine that the installation of nest boxes has increased the presence of kestrels in the region between 2013 and 2016. Chapters 1 and 2 indicate that orchard nest boxes can benefit the local conservation of kestrels by increasing breeding populations, which may in turn benefit agriculture by promoting kestrel presence, and therefore predation on pest species, in and around orchards. In Chapter 3, I used nest box video cameras to determine that kestrels provision their nestlings with known orchard pests, including grasshoppers, voles, and frugivorous birds; furthermore, I observed generalizable trends in kestrel prey removal based on nestling age, seasonal timing of prey availability, brood size and sex ratio, weather, and adult female movements relative to the nest box. In Chapter 4, I used transect surveys to determine that fruit-eating bird counts were lower in orchards with active kestrel nest boxes, thus kestrel activity associated with nest boxes likely acts as a reliable cue of predation risk that, in combination with direct consumption, reduces fruit-eating bird abundances in orchards. Finally, in Chapter 5, I used live-trapping to determine that summer small mammal abundances were lower in orchards with active kestrel boxes and orchards that had been more recently mowed; however, these differences did not carry over as differences in winter presence in orchards, when mammal damage to trees is most likely. Based on the results, I recommend that future projects utilize a consistent surveying protocol across seasons, conduct winter surveys in orchards without rodenticide use, and combine small mammal surveys with fruit and tree damage assessments in order to identify which species are responsible for damage throughout the year and under different conditions (e.g., with variation in snowfall).
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Title: Impact of wind generation on grid frequency stability
Creator: Nguyêñ, Nga (Graduate of Michigan State University)
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The integration of renewable energy sources into power systems has gathered significant momentum globally because of its unlimited supply and environmental benefits. Within the portfolio of renewable energy, wind power has been experiencing a steadily increasing growth. Despite its well known benefits, wind power poses several challenges in grid integration. The inherent intermittent and non-dispatchable features of wind power not only inject additional fluctuations to the already variable...
Show moreThe integration of renewable energy sources into power systems has gathered significant momentum globally because of its unlimited supply and environmental benefits. Within the portfolio of renewable energy, wind power has been experiencing a steadily increasing growth. Despite its well known benefits, wind power poses several challenges in grid integration. The inherent intermittent and non-dispatchable features of wind power not only inject additional fluctuations to the already variable nature of frequency deviation, they also decrease frequency stability and reliability by reducing the inertia and the regulation capability. To ensure the system security, the integration of wind power must be limited and the wind generation has to operate in the condition that enables wind generator to support the frequency control. As a result, the reliability of wind power must be re-estimated based on the wind power that can be accepted by the system, instead of the total wind production. This research examines the impacts of wind generation on system inertia and theregulation capability as well as the effect on tie-line flows and area control error. The effect of wind power on frequency regulation capability at different penetration levels is also investigated. The mathematical and simulation model to determine maximum wind power penetration level, given a frequency deviation limit, is developed. Based on the proposed mathematical model of wind penetration limit, the negative impact of wind on system reliability is examined. An improved method to coordinate the energy storage with the existing system to improve the wind-integrated system reliability while maintaining the system frequency security is also proposed. An approachto assist the integration of wind power with grid-scale virtual energy storage will be developed and examined. This thesis discusses the pertinent background and state of the art, and describes the proposed approaches and the results obtained.
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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: Local food in perspective : place, time, authenticity, and the relocalization of the food system
Creator: Giorda, Erica
Date: 2017
Collection: Electronic Theses & Dissertations
Description: While the research on local food systems and movements is well established, the time related aspects of local food promotion, production, and consumption have been barely explored.This dissertation starts to address that topic through three articles: a theoretical analysis of time and agency in food relocalization processes, and two case studies that address ideas of authenticity and heritage, community ties, and place making practices based on the selective framing of shared temporalities at...
Show moreWhile the research on local food systems and movements is well established, the time related aspects of local food promotion, production, and consumption have been barely explored.This dissertation starts to address that topic through three articles: a theoretical analysis of time and agency in food relocalization processes, and two case studies that address ideas of authenticity and heritage, community ties, and place making practices based on the selective framing of shared temporalities at Eastern Market in Detroit.First, I use French Convention Theory to examine how a set of vendors at Eastern Market in Detroit sell their food emphasizing craftsmanship and cultural values more than price or provenance. The work of these vendors manifests a form of compromise between the Domestic and Market worlds that is based on reputation and regard. This shifts the meaning of local food from provenance to a form of authenticity based on the presentation of heritage and community ties.Second, I investigate the ways local actors use the physical arrangements of the space inside and around the Market and how the promotion of local food through new and old references to craftsmanship, care and tradition contribute to the creation of a sense of place. Following Gieryn and Molotch et al., place-making is presented as a recursive process led by ‘strategically placed actors’ (Giddens 1984) whose action creates a conceptual narrative that may create exclusionary spaces. I adopt a visual approach to offer a fresh perspective in terms of understanding the intersection of time and space, history and geography, as well as clarifying how ideas of locality and place are performed.Third, I analyze embeddedness as pertinent to local food systems, from the perspective of time. Drawing from ethnographic research and current literature I highlight the different ways in which time is a relevant variable that makes food embedded in social systems and reduces the alienating effects of the commodification of the food chain. Appeals to tradition, history, ancestry, duration, co-presence and time commitment are different time-related aspects that support the embedding of food production, preparation, and consumption. This approach also allows for identifying agency in wider sets of actions and behaviors than looking at spatial patterns only.The three papers together contribute to increasing the understanding and theorization of place making processes, the relevance of seemingly marginal practices with respect to the determination of agency, and to increasing the focus on the temporal gaze in relation to commodification and de-commodification practices in the areas of local food production and consumption.
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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: Knowledge, risk, and benefit perceptions : using participatory video and tailored mobile messages to motivate farmers' uptake of drought tolerant (DT) maize seed in kenya
Creator: Cai, Tian (Graduate of Michigan State University)
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "This research documents the design and testing of two strategies for using information and communication technologies (ICTs) to increase farmers' knowledge and uptake of DT maize: (1) locally-made, or 'participatory' video, and (2) a multichannel method that incorporates the same video with timely mobile phone-based audio messages. We conducted a randomized field experiment in Machakos and Makueni counties in Kenya. The experiment randomly allocated the two strategies to farmers in the study...
Show more"This research documents the design and testing of two strategies for using information and communication technologies (ICTs) to increase farmers' knowledge and uptake of DT maize: (1) locally-made, or 'participatory' video, and (2) a multichannel method that incorporates the same video with timely mobile phone-based audio messages. We conducted a randomized field experiment in Machakos and Makueni counties in Kenya. The experiment randomly allocated the two strategies to farmers in the study areas. It was found that, after implementing these interventions, farmers in the multichannel group demonstrated significantly higher knowledge about DT maize and its accompanying management practices. Further, they were significantly more likely to report purchasing improved seed as well as intending to plant DT maize than the farmers in the video-only and the control groups. Farmers in the video-only group did gain a higher level of knowledge than the farmers in the control group; however, this difference is not statistically significant. Moreover, farmers' perceived risk regarding DT maize was found to be associated with their level of knowledge on the varieties and to which kind of treatments they are exposed. Farmers in the two treatment groups showed lower perceived risk than farmers in the control group, especially in the multichannel group. Mitigating the perceived risk of growing the varieties played a crucial role in motivating farmers to test DT maize. We found risk perception was more likely to decrease willingness to test DT maize among farmers who retained lower levels of knowledge than the farmers who had higher levels of knowledge. The results suggest that an ICT strategy integrating multiple ICTs can effectively communicate contextualized knowledge and timely reminders to farmers. This strategy helped farmers gain knowledge about DT maize and induced them to test new seed varieties. This finding contributes to existing theories on the usage of ICTs in agricultural knowledge provision. Previous literature mainly discusses whether single ICTs can improve farmers' knowledge and uptake (e.g. Gandhi, et al., 2009; Cole & Fernando, 2012), while this study investigates how to design ICT-based approaches by integrating various ICTs to make them more effective in innovation diffusion. In this case, those designing ICT strategies should consider farmers' cognitive capacities and the characteristics of agricultural innovations, such as complexity and whether farmers need to practice multiple steps at various points in a growing cycle, as such design can influence farmers' learning and uptake of the innovations. Lastly, this study contributes to a greater understanding of farmers' knowledge and perceptions of DT maize and how they are associated with farmers' uptake decisions."--Pages ii-iii.
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Title: An analysis of content knowledge and cognitive abilities as factors that are associated with algebra performance
Creator: McLean, Tamika Ann
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The current study investigated college students' content knowledge and cognitive abilities as factors associated with their algebra performance, and examined how combinations of content knowledge and cognitive abilities related to their algebra performance. Specifically, the investigation examined the content knowledge factors of computational fluency, numeracy skills, fraction knowledge, understanding of equivalence, and algebraic reasoning skills, and the cognitive abilities of spatial...
Show more"The current study investigated college students' content knowledge and cognitive abilities as factors associated with their algebra performance, and examined how combinations of content knowledge and cognitive abilities related to their algebra performance. Specifically, the investigation examined the content knowledge factors of computational fluency, numeracy skills, fraction knowledge, understanding of equivalence, and algebraic reasoning skills, and the cognitive abilities of spatial visualization, crystallized intelligence, and fluid intelligence. A multiple regression analysis found that while controlling for gender, the highest math course taken, and the number of years since an algebra course, fraction knowledge and the spatial visualization ability of spatial imagery were statistically significant predictors of algebra performance along with the control variable identifying whether or not participants had taken at least one calculus course. In addition, cluster analysis identified six content knowledge and cognitive ability profiles, with varying levels of both content knowledge and cognitive abilities observed across the six clusters. The six profiles - characterized as Low All, Moderate-Low All, Moderate-High MASMI, Moderate-Low Spatial, Moderate-High All, and High Spatial - varied somewhat in terms of their algebra performance scores. In particular, the participants in the High Spatial cluster group and participants in the Moderate-High All cluster group had similarly high algebra performance scores, which were significantly higher than performances scores observed for participants in the other cluster groups. Additionally, the participants in the other cluster groups exhibited similar low algebra performance scores to each other except for participants in the in the Moderate-Low Spatial and Low All cluster groups. Participants in the Moderate-Low Spatial cluster group had significantly higher algebra performance scores than participants in the Low All cluster group. The differences in algebra performance scores among cluster groups suggested that the observation of higher algebra performance occurred when participants had strong spatial visualization skills, strong fluid intelligence skills, and high content knowledge or when participants had strong fraction knowledge, numeracy skills, algebraic reasoning skills, and spatial imagery skills."--Pages ii-iii.
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Title: Essays on pseudo panel data and treatment effects
Creator: Jia, Fei (College teacher)
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This dissertation is composed of three chapters that study two suitable estimation methods for identifying causal relationships in the presence of (pseudo) panel data. The first and the second chapters are devoted to minimum distance estimation for pseudo panel models, whereas the third chapter is concerned with the estimation of controlled direct effects in causal mediation analyses using panel data.The first chapter focuses on finite sample properties of minimum distance estimators in...
Show moreThis dissertation is composed of three chapters that study two suitable estimation methods for identifying causal relationships in the presence of (pseudo) panel data. The first and the second chapters are devoted to minimum distance estimation for pseudo panel models, whereas the third chapter is concerned with the estimation of controlled direct effects in causal mediation analyses using panel data.The first chapter focuses on finite sample properties of minimum distance estimators in pseudo panel models. Previous research shows theoretically that the minimum distance asymptotic theory is a natural fit for pseudo panel models when cohort sizes are large. However, little is known about how minimum distance estimation performs with a realistic sample size. In a carefully designed simulation study that mimics the sampling scheme of repeated cross sections, we compare the optimal minimum distance estimator to the fixed effects estimator which is identical to the minimum distance estimators using identity weighting matrix. The results show that both estimators perform well in realistic finite sample setups. The results also confirm that the optimal minimum distance estimator is generally more efficient than the fixed effect estimator. In particular, we find that cohort-wise heteroskedasticity and varying cohort size are the two typical scenarios that call for the use of optimal weighting. For the fixed effects estimator, we find that the minimum distance inference is more suitable than the naive inference which incorrectly ignores the estimation errors in the pseudo panel of variable cohort means.The second chapter extends the basic pseudo panel models in the first chapter by adding extra instrumental variables. The additional instruments, if non-redundant, can improve estimation efficiency. To have the efficiency gain result in a general form, we derive it in a non-separable minimum distance framework developed in this chapter. Along with the efficiency gain result, consistency, asymptotic normality, and optimal weighting theorems are also established. This efficiency gain result echoes the property of generalized methods of moments that more moment conditions do not hurt. After developing the results in the non-separable minimum distance framework, we apply them to the extended pseudo panel models. we show that the minimum distance estimators in the extended pseudo panels are generalized least squares estimators, and the optimal weighting matrix is block diagonal. Because of the last fact, the use of optimal weighting becomes more important than in basic pseudo panels. Simulation evidence confirms the theoretical findings in realistic finite sample setups. For an empirical illustration, we apply the method to estimate returns to education using data from the Current Population Survey in the US.The third chapter, coauthored with Zhehui Luo and Alla Sikorskii, proposes a flexible plug-in estimator for controlled direct effects in mediation analyses using the potential outcome framework. A controlled direct effect is the direct treatment effect on an outcome when the indirect treatment effect through a mediator is shut off by holding the mediator fixed. The flexible plug-in estimator for controlled direct effects is a parametric g-formula with an additional partially linear assumption on the outcome equation. Compared to simulation based method in the literature, this estimator avoids estimation of conditional densities and numerical evaluation of expectations. We compare the flexible plug-in estimator to the sequential g-formula estimator, and prove theoretically and via simulation that they are numerically equivalent under certain settings. We also discuss a sensitivity analysis to check the robustness of the flexible plug-in estimator to a particular violation of the sequential ignorability assumption. We illustrate the use of the flexible plug-in estimator in a secondary analysis of a random sample of low birthweight and normal birthweight infants to estimate the controlled direct effect of low birth weight on reading scores at age 17 when a behavior problem index is used as the mediator.
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Title: The role of biodiversity in prairie restoration : tests of theory and implications for management
Creator: Bassett, Tyler Jacob
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Biodiversity is a primary focus of conservation and restoration, because it has intrinsic value, and because it supports the ecosystem functioning that human well being ultimately depends upon. Theory and experiments support the hypothesis that greater diversity in plant communities supports greater primary productivity, nutrient cycling, invasion resistance and a range of other processes linked to the healthy functioning of ecosystems. However, most of the evidence for diversity-function...
Show more"Biodiversity is a primary focus of conservation and restoration, because it has intrinsic value, and because it supports the ecosystem functioning that human well being ultimately depends upon. Theory and experiments support the hypothesis that greater diversity in plant communities supports greater primary productivity, nutrient cycling, invasion resistance and a range of other processes linked to the healthy functioning of ecosystems. However, most of the evidence for diversity-function relationships is from manipulations of diversity, and a limited number of environmental variables, in small-scale plots. As a result, it is unclear how diversity-function relationships will scale up to dynamic, "real-world" ecosystems, which limits the capacity to effectively manage both biodiversity and ecosystem functioning. I examined diversity-function relationships in prairie restorations, which provide an ideal scenario for bridging the gap between experimental and natural ecosystems because diversity is manipulated at large scales and across complex biotic and abiotic gradients. It is clear from experimental evidence that diversity plays a role in supporting ecosystem functioning. My findings elucidate how important diversity is at the scale of natural ecosystems, relative to both abiotic (e.g., soil properties) and biotic (e.g., dominant species) factors that are likely to covary with diversity at large scales. I also contribute directly to the practice of restoration by working in real restorations, linking variation in management actions, such as seed sowing and prescribed fire, to outcomes of immediate concern to managers, such as the relationship between native and exotic species."--Abstract.
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Title: Social Distance in Iraq and Lebanon
Creator: Mohammed, Jihan A.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Research has found that tensions, conflicts, and wars worsen the views groups hold towards each other and, plausibly, increase social distance. ... Since the twentieth century the Middle East is caught up in interlocking pattern of crises, conflicts, wars, and terrorism. Almost every country in the region have serious problems in social and political stability. The focus of this study is to investigate levels of social distance in conflict areas like Iraq and Lebanon where thousands of...
Show moreResearch has found that tensions, conflicts, and wars worsen the views groups hold towards each other and, plausibly, increase social distance. ... Since the twentieth century the Middle East is caught up in interlocking pattern of crises, conflicts, wars, and terrorism. Almost every country in the region have serious problems in social and political stability. The focus of this study is to investigate levels of social distance in conflict areas like Iraq and Lebanon where thousands of people have been killed and displaced because of civils wars and counter-terrorism. ... We are specifically interested to see the relative importance of: practicing religious rituals i.e. praying, fasting, attending Friday prayer/Sunday service; sectarian/denominational identification; and voting behavior as determinants of social distance.--Abstract
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Title: "Lost space" and "artialised space" : analyzing photographic representations in Paris
Creator: Hou, Xiao
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Photographs are ubiquitous, and we seem to understand the world through photographs a lot more. But how does the ubiquitous photographic representation affect our understanding of the urban environment? The main aim of this study was to examine and explore how and why a city is represented in people's photographs differently." -- Abstract.

Title: Cultural elements relative to dietary behaviors for diabetes self-management among Mexican-Americans
Creator: Plasencia, Julie
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Specific aspects of culture relative to Mexican-Americans have not been characterized relative to medical nutrition therapy (MNT) and/or education for in type 2 diabetes mellitus (T2DM) self-management and other health problems. The objective of the study is to add meaningful insight into culturally relevant aspects necessary for the development and/or adaptation of T2DM self-management programming for Mexican-Americans. To accomplish this, aspects of culture relative to T2DM self-management...
Show moreSpecific aspects of culture relative to Mexican-Americans have not been characterized relative to medical nutrition therapy (MNT) and/or education for in type 2 diabetes mellitus (T2DM) self-management and other health problems. The objective of the study is to add meaningful insight into culturally relevant aspects necessary for the development and/or adaptation of T2DM self-management programming for Mexican-Americans. To accomplish this, aspects of culture relative to T2DM self-management are explored through several innovative approaches. First, using a content analysis approach, an in-depth examination of literature on the perceptions of Mexican-Americans on self-management diet and physical activity behaviors was completed to identify cultural elements. Next, perceptions of culture by nutrition experts, specifically targeting registered dietitians, were examined using an online survey that explores cultural elements used in practice when counseling Mexican-American diabetes patients on achievement of self-management goals. Finally, curricula used in T2DM interventions that target Mexican-Americans were examined using a content analysis approach for the extent to which cultural elements are integrated into the written curricula. Results from the first aim identified several surface and deep level cultural elements. The top surface level elements mostly frequently found in the qualitative studies were food habits (n=15/19), food preferences (n=14/19), use or acquisition of nutrition knowledge (11/19) and healthcare provider preferences (11/19). The top three deep level elements most commonly found were general health beliefs or attitudes (n=19/19), beliefs or attitudes about foods in general (n=17/19) and family turmoil (n=14/19). Findings from the second aim demonstrated that Registered Dietitian Nutritionist (RDNs) vary in their perceptions of cultural elements depending on years of professional experience. For example, the least experienced RDNs (average of 4.62 years) were more likely to perceive that beliefs about Mexican and American foods in general important for diabetes self-management compared to the highly experienced group of RDNs (average of 33.98 years). Additionally, RDNs who provided T2DM counseling to Mexican-Americans were more likely to fall in the least experienced group, be Certified Diabetes Educators, work in outpatient settings and provide individual counseling. With regards to cultural competency levels assessed, there were no differences assessed between the three experience levels RDNs were grouped in.The final aim examined how six T2DM intervention curricula incorporated cultural elements. The results of this content analysis showed that the main cultural elements incorporated were related to diet were food habits, food preferences or avoidances, acquisition and use of nutrition knowledge, beliefs about Mexican/cultural foods and general health beliefs about foods. Specific health beliefs and values commonly recognized as influential factors for self-management and healthcare seeking behaviors for Mexican-Americans were less likely to be addressed. However, overcoming barriers, general health beliefs about diabetes and family influences were incorporated in some of the curricula.Through this research, we identified that there is a demand for culture-specific cultural competency trainings among RDNs and that several tools are available to encourage dissemination of evidence-based findings such as integrating background information in diabetes self-management curricula and cultural competency training opportunities (such as professional development and higher education). Overall, these results suggest that culture-specific knowledge is not uniformly evident in nutrition therapy practice when Mexican-Americans who have T2DM. This may also be true for all healthcare professions working with this and other ethnic populations. Therefore, future research should focus on identifying opportunities for culture-specific cultural competency training, how these trainings transfer into better outcomes for patients, and finally, examining which and how cultural elements provide better behavior change outcomes in interventions.
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Title: Whole tree renewal regenerates fruiting structures quickly in mature orchards
Creator: Larson, James Edward
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Renewal of fruiting wood to maintain young reproductive meristems with optimal canopy light interception and distribution is key for high productivity and fruit quality throughout the life of a sweet cherry (Prunus avium L.) orchard. Typical renewal involves replacement of 10 to 20% of the tree canopy annually by removing one to several of the largest branches. In a mature orchard, this renewal process is subject to competition between sun-exposed fruiting sites and interior canopy renewal...
Show moreRenewal of fruiting wood to maintain young reproductive meristems with optimal canopy light interception and distribution is key for high productivity and fruit quality throughout the life of a sweet cherry (Prunus avium L.) orchard. Typical renewal involves replacement of 10 to 20% of the tree canopy annually by removing one to several of the largest branches. In a mature orchard, this renewal process is subject to competition between sun-exposed fruiting sites and interior canopy renewal sites that intercept less light and compete poorly for translocated photoassimilates, often resulting in poor renewal growth. This is particularly problematic for high density orchards that utilize rootstocks selected for reduced vigor and high productivity. Renewal of canopy fruiting sites on a whole tree basis is an alternative renewal method that eliminates the competitive inhibition of shoot regrowth. This study explores the initial response of sweet cherry trees on various training systems and size-controlling rootstocks to whole tree renewal. Four training systems were studied: Tall Spindle Axe, Super Slender Axe, Upright Fruiting Offshoots, and Kym Green Bush. In 2016, whole tree renewal of the four systems was studied with ‘Benton’ cultivar on three rootstocks of varying vigor: Gisela 3, Gisela 5, and Gisela 6. During bloom, all fruit-bearing components of the canopy were pruned back to stubs close to the permanent structure. TSA resulted in the higher number of shoots, while KGB and UFO had the longest average shoot length. The results indicate that each canopy system-rootstock combination refilled canopy space, except for KGB on each rootstock, to quickly regenerate fruiting sites.
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Title: Remains of Khmer Rouge Violence : the Materiality of Bones as Scientific Evidence and Affective Agents of Memory
Creator: Fleischman, Julie Michele
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The Khmer Rouge regime, led by the infamous Pol Pot, governed Cambodia from 1975 to 1979. Living conditions were severe, and it is estimated that approximately one quarter of the Cambodian population of nearly eight million died from mistreatment, overwork, malnutrition, and violence. Using a biocultural anthropological approach, this research addressed questions concerning individuals executed by the Khmer Rouge regime and the agency (the effect on living individuals) of the resulting...
Show moreThe Khmer Rouge regime, led by the infamous Pol Pot, governed Cambodia from 1975 to 1979. Living conditions were severe, and it is estimated that approximately one quarter of the Cambodian population of nearly eight million died from mistreatment, overwork, malnutrition, and violence. Using a biocultural anthropological approach, this research addressed questions concerning individuals executed by the Khmer Rouge regime and the agency (the effect on living individuals) of the resulting skeletal remains.An osteological analysis of more than 500 crania was conducted at the Choeung Ek Genocidal Center (Choeung Ek) in Phnom Penh. More than 100 original Khmer Rouge execution lists from the detention and torture facility known as S-21—today known as the Tuol Sleng Genocide Museum—were assessed to gather known demographic data for those who were executed and buried at Choeung Ek between 1977 and 1979. To comprehend the incorporation of human skeletal remains from the Khmer Rouge period into the socio-religious framework of modern Cambodia, 13 memorial stupa containing human remains were visited and the caretakers of these memorials were interviewed.The 508 crania at Choeung Ek were assessed for demographic characteristics and traumatic injuries. Results indicate that the majority of crania were estimated to be male (82.9%) and nearly all were of Asian ancestry (86%). The majority of the individuals were young adults (68.3%) between the ages of 20 and 35 years old, although juveniles and older adults were represented. Perimortem trauma was present on 311 crania (61%), with 179 (58%) having discernable impact locations. Blunt force injuries (87%) were the most common mechanism of trauma and the basicranium (53%) was the most frequently impacted region. When the mechanism and location of traumatic injuries were evaluated by sex and age-at-death categories, no statistically significant differences were found indicating that all victims with perimortem trauma were subjected to similar execution methods regardless of their age or sex.At the Tuol Sleng Genocide Museum, 97 definitive Khmer Rouge execution lists were evaluated documenting the murders of 6,285 individuals. The majority (82.1%) were male, the minimum age was 11, the maximum age was 77, and the average age was 29.1 years. When these archival demographic data were compared to these osteologial data, however, there were statistically significant differences between the samples.Observational data from all 13 memorials, and interview data from 10 memorials indicated that the human remains were not formally preserved to prevent decay and there was never a clear indication of how many individuals were represented by the remains with the stupa. The informant’s responses addressed issues such as the identification of the human remains within the memorial, current religious practices conducted at the memorials often in conjunction with caring for the remains, how the remains are displayed for knowledge and/or teaching purposes—although often with a political undertone—and that the memory of the Khmer Rouge period, as well as that of the victims is crucial for modern Cambodians.This research embraced a holistic approach to move beyond the confines of traditional osteological laboratory research by addressing the social impact of the remains. While the Khmer Rouge period was devastating, the human remains of the victims have not been forgotten; the remains continue to remind all who visit that immeasurable violence occurred in Cambodia but also that Cambodians are resilient and they will continue to memorialize those they lost.
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Title: Suicide, signals, and symbionts : evolving cooperation in agent-based systems
Creator: Vostinar, Anya E.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Cooperation is ubiquitous in nature despite the constant pressure for organisms to cheat by receiving a benefit from cooperators, while not cooperating themselves. The continued evolution and persistence of countless forms of cooperation is a central topic in evolutionary theory. Extensive research has been done on the theoretical dynamics of cooperation through game theory and the natural examples of cooperation. However, it remains difficult to understand thoroughly the evolution of many...
Show moreCooperation is ubiquitous in nature despite the constant pressure for organisms to cheat by receiving a benefit from cooperators, while not cooperating themselves. The continued evolution and persistence of countless forms of cooperation is a central topic in evolutionary theory. Extensive research has been done on the theoretical dynamics of cooperation through game theory and the natural examples of cooperation. However, it remains difficult to understand thoroughly the evolution of many cooperative systems, due in part to the ancient origins of these systems and the long time scales required to see cooperation evolve in any natural populations. I have systematically analyzed the evolution of three broad types of cooperation: programmed cell death, quorum sensing, and mutualisms (cooperation across species). I have provided evidence that programmed cell death can originate due to kin selection. I have also created two new systems to enable the extensive exploration of factors that affect the evolution of public goods cooperation and mutualism. Using these systems, I determine the effects of environmental factors on the evolution of public goods cooperation and mutualism. By uniting the expansive theoretical work on these forms of cooperation with a fully-controlled experimental system, I contributed to our understanding of how these forms of cooperation can emerge and be maintained in industrial and medical applications that rely on bacterial cooperation.
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