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Title: Example-Based Parameterization of Linear Blend Skinning for Skinning Decomposition (EP-LBS
Creator: Hopkins, Kayra M.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This thesis presents Example-based Parameterization of Linear Blend Skinning for Skinning Decomposition (EP-LBS), a unified and robust method for using example data to simplify and improve the development and parameterization of high quality 3D models for animation. Animation and three-dimensional (3D) computer graphics have quickly become a popular medium for education, entertainment and scientific simulation. In addition to film, gaming and research applications, recent advancements in...
Show moreThis thesis presents Example-based Parameterization of Linear Blend Skinning for Skinning Decomposition (EP-LBS), a unified and robust method for using example data to simplify and improve the development and parameterization of high quality 3D models for animation. Animation and three-dimensional (3D) computer graphics have quickly become a popular medium for education, entertainment and scientific simulation. In addition to film, gaming and research applications, recent advancements in augmented reality (AR) and virtual reality (VR) are driving additional demand for 3D content. However, the success of graphics in these arenas depends greatly on the efficiency of model creation and the realism of the animation or 3D image.A common method for figure animation is skeletal animation using linear blend skinning (LBS). In this method, vertices are deformed based on a weighted sum of displacements due to an embedded skeleton. This research addresses the problem that LBS animation parameter computation, including determining the rig (the skeletal structure), identifying influence bones (which bones influence which vertices), and assigning skinning weights (amounts of influence a bone has on a vertex), is a tedious process that is difficult to get right. Even the most skilled animators must work tirelessly to design an effective character model and often find themselves repeatedly correcting flaws in the parameterization. Significant research, including the use of example-data, has focused on simplifying and automating individual components of the LBS deformation process and increasing the quality of resulting animations. However, constraints on LBS animation parameters makes automated analytic computation of the values equally as challenging as traditional 3D animation methods. Skinning decomposition is one such method of computing LBS animation LBS parameters from example data. Skinning decomposition challenges include constraint adherence and computationally efficient determination of LBS parameters.The EP-LBS method presented in this thesis utilizes example data as input to a least-squares non-linear optimization process. Given a model as a set of example poses captured from scan data or manually created, EP-LBS institutes a single optimization equation that allows for simultaneous computation of all animation parameters for the model. An iterative clustering methodology is used to construct an initial parameterization estimate for this model, which is then subjected to non-linear optimization to improve the fitting to the example data. Simultaneous optimization of weights and joint transformations is complicated by a wide range of differing constraints and parameter interdependencies. To address interdependent and conflicting constraints, parameter mapping solutions are presented that map the constraints to an alternative domain more suitable for nonlinear minimization. The presented research is a comprehensive, data-driven solution for automatically determining skeletal structure, influence bones and skinning weights from a set of example data. Results are presented for a range of models that demonstrate the effectiveness of the method.
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Title: Refining trunk injection strategies for control of foliar insect pests and disease in Michigan apple orchards
Creator: Coslor, Charles Clark, 1988-
Date: 2017
Collection: Electronic Theses & Dissertations
Description: In conventional apple orchards, insect pests are managed with insecticides delivered to the canopy using airblast sprayers, which provide good canopy coverage. However, spraying results in significant product loss: as little as 26% is estimated to reach the tree canopy due to spray drift and less than 0.1% of insecticide ends up reaching the target pest. The remainder is lost to the environment with potential to harm people or non-target organisms. Trunk injection is a discriminating...
Show moreIn conventional apple orchards, insect pests are managed with insecticides delivered to the canopy using airblast sprayers, which provide good canopy coverage. However, spraying results in significant product loss: as little as 26% is estimated to reach the tree canopy due to spray drift and less than 0.1% of insecticide ends up reaching the target pest. The remainder is lost to the environment with potential to harm people or non-target organisms. Trunk injection is a discriminating pesticide delivery system which reduces insecticide inputs and environmental exposure by delivering chemicals directly to the vascular system. It is commonly used to deliver pesticides in ornamental and shade trees. Recent work with trunk injection in apple orchards has shown promise, but more research must be done to determine efficacy and safety in tree fruit crops. In the following studies, we injected emamectin benzoate, imidacloprid, dinotefuran, spinosad, chlorantraniliprole, and abamectin into apple trees to expand the list of insecticides compatible with trunk injection. Nectar and pollen were sampled from trees to compare the effects of injection timing on insecticide concentration in floral resources. In addition, two fundamental injection tool types were compared: drill-based and needle-based. To test compatibility of combined insect and disease management, an insecticide and a fungicide were injected simultaneously. Finally, low-volume injections were performed on nursery apple trees, which normally require high pesticide inputs and do not produce fruit for several years. Emamectin benzoate, chlorantraniliprole and abamectin resulted in moderate to high mortality and reduced feeding in Choristoneura rosaceana bioassays using leaves sampled from trunk injected apple trees. Neonicotinoids reduced Empoasca fabae density in field evaluations, and also showed activity on C. rosaceana at higher concentrations. Spinosad was not well-transported within the apple tree vascular system. Numbers of E. fabae nymphs were lower on trees injected with imidacloprid using a drill-based tool compared with untreated trees in all years, despite a trend of initially higher foliar concentrations with the needle-based tool. This demonstrated that delivery method is an important factor in effective trunk injection based apple management. We found that when an insecticide and a fungicide are injected, they can interact dynamically within the vascular system of a tree. Injections of emamectin benzoate followed by phosphorous acid into the same set of injection ports resulted in higher mortality of C. rosaceana larvae and lower incidence of apple scab compared with untreated trees. This has important implications for expanding the utility of trunk injection for fruit tree management. Nursery tree injections were most effective when emamectin benzoate was injected into the trunk versus the taproot. A rate equivalent to 1/8 the rate used for mature tree injection reduced insect pests more than a 1/80 rate. The higher rate of emamectin benzoate was also persistent in the following year. Imidacloprid and emamectin benzoate were injected in the spring and fall, and nectar and pollen were sampled the following spring. Imidacloprid was not detected in nectar or pollen when injected in the previous spring. Conversely, emamectin benzoate was detected when injected in the previous spring, but was not detected in nectar or pollen when injected in the fall. This study expanded the list of insecticides compatible with trunk injection, demonstrated novel uses of trunk injection to reduce insect pests in apple trees, and introduced possible ways to mitigate accumulation of insecticides in nectar and pollen.
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Title: Legitimacy of criminal justice organizations and democratic structures in countries of Africa : a comparison of 33 nations
Creator: Gillespie, Nolan Thomas
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The aim of this research is to examine perceived legitimacy in criminal justice organizations in less advanced democracies, specifically those that are considered flawed, hybrid, or authoritarian. More specifically the study examines how procedural fairness, corruption, social capital, and degrees of democracy effect trust in police and courts among African countries that differ significantly on various democracy metrics with data drawn from 33 African nations. The inquiry attempts to...
Show more"The aim of this research is to examine perceived legitimacy in criminal justice organizations in less advanced democracies, specifically those that are considered flawed, hybrid, or authoritarian. More specifically the study examines how procedural fairness, corruption, social capital, and degrees of democracy effect trust in police and courts among African countries that differ significantly on various democracy metrics with data drawn from 33 African nations. The inquiry attempts to reconcile the implications of democratic society with perceptions of criminal justice organizations. Findings and implications are discussed." -- Abstract.
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Title: The effects of doping and processing on the thermoelectric properties of platinum diantimonide based materials for cryogenic Peltier cooling applications
Creator: Waldrop, Spencer Laine
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The study of thermoelectrics is nearly two centuries old. In that time a large number of applicationshave been discovered for these materials which are capable of transforming thermalenergy into electricity or using electrical work to create a thermal gradient. Current use ofthermoelectric materials is in very niche applications with contemporary focus being upontheir capability to recover waste heat. A relatively undeveloped region for thermoelectricapplication is focused upon Peltier...
Show moreThe study of thermoelectrics is nearly two centuries old. In that time a large number of applicationshave been discovered for these materials which are capable of transforming thermalenergy into electricity or using electrical work to create a thermal gradient. Current use ofthermoelectric materials is in very niche applications with contemporary focus being upontheir capability to recover waste heat. A relatively undeveloped region for thermoelectricapplication is focused upon Peltier cooling at low temperatures. Materials based on bismuthtelluride semiconductors have been the gold standard for close to room temperature applicationsfor over sixty years. For applications below room temperature, semiconductors basedon bismuth antimony reign supreme with few other possible materials.The cause of this diculty in developing new, higher performing materials is due tothe interplay of the thermoelectric properties of these materials. The Seebeck coecient,which characterizes the phenomenon of the conversion of heat to electricity, the electricalconductivity, and the thermal conductivity are all interconnected properties of a materialwhich must be optimized to generate a high performance thermoelectric material. While forabove room temperature applications many advancements have been made in the creationof highly ecient thermoelectric materials, the below room temperature regime has beenstymied by ill-suited properties, low operating temperatures, and a lack of research.The focus of this work has been to investigate and optimize the thermoelectric propertiesof platinum diantimonide, PtSb2, a nearly zero gap semiconductor. The electronic propertiesof PtSb2 are very favorable for cryogenic Peltier applications, as it exhibits good conductivityand large Seebeck coecient below 200 K. It is shown that both n- and p-type dopingmay be applied to this compound to further improve its electronic properties. Throughboth solid solution formation and processing techniques, the thermal conductivity may bereduced in order to increase the thermoelectric gure of merit. Further reduction in thermalconductivity using other novel approaches is identied as an area of promising future research.Continued development of this material has the potential to generate a suitable replacementfor some low temperature applications, but will certainly further scientic knowledge andunderstanding of the optimization of thermoelectric materials in this temperature regime.
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Title: Electromagnetic transition strengths studied with Doppler-shift techniques across the contours of the valley of stability
Creator: Loelius, Charles Robert
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The electromagnetic transition strengths between bound states in nuclei provide insight into nuclear structure. On one hand, from a single particle perspective the electromagnetic excitation and de-excitation of nuclei quantify the overlaps of nuclear wavefunctions, probing the internal configuration. On the other hand, in a collective model, the shape and dynamics of the nucleus are reflected in the electromagnetic transition strengths. For example, electric quadrupole transitions are...
Show moreThe electromagnetic transition strengths between bound states in nuclei provide insight into nuclear structure. On one hand, from a single particle perspective the electromagnetic excitation and de-excitation of nuclei quantify the overlaps of nuclear wavefunctions, probing the internal configuration. On the other hand, in a collective model, the shape and dynamics of the nucleus are reflected in the electromagnetic transition strengths. For example, electric quadrupole transitions are sensitive to the deformation of a nucleus and distinguish between various pictures of collectivity, such as rotors and vibrators. In this work, electromagnetic transition strengths are studied through lifetime and Coulomb-excitation measurements. Nuclei across the contours of the valley of stability are studied to investigate features of nuclear structure and how they change near and far from stability.The first experiment discussed in this work investigates the effect of the $N=Z=28$ shell closure on collectivity in $^{58}$Ni. $^{58}$Ni has 28 protons and 30 neutrons, and therefore is not expected to exhibit enhanced collectivity compared to its neutron rich neighbors. However, a previous measurement of the lifetime of the $4_1^+$ state indicates an enhanced $B(E2;4_1^+\rightarrow2_1^+)$ transition strength, suggesting unexpectedly large collectivity. The present work revisits the lifetime of the $4_1^+$ state with a more sensitive technique, namely a Recoil Distance Method measurement at the National Superconducting Cyclotron Laboratory. The GRETINA detector array was employed with the S800 Spectrograph to measure the $4_1^+$ state lifetime. The model independent $B(E2;4_1^+\rightarrow2_{1}^+)$ from the present work supports an unenhanced transition strength, as expected near the shell closure.The second experiment discussed in this work is a study of the electromagnetic transition states in $^{27}$Ne. $^{27}$Ne is a loosely-bound neutron rich nucleus although it does not exhibit a halo structure in its ground state. This work investigates the excited states of $^{27}$Ne that lie closer to the particle threshold for features associated with a halo structure. The lifetimes of the $1/2^+$ and $3/2^-$ states in $^{27}$Ne and the branching ratio of the $1/2^+$ state decaying into the $3/2^-$ excited state and $3/2^+_{gs}$ ground state are measured. These values are used to determine the $B(E1;3/2^-\rightarrow3/2^+_{gs})$ and $B(E1;1/2^+\rightarrow3/2^-)$ values. It was found that the $B(E1)$ connecting the $1/2^+$ state to the $3/2^-$ state is at least 50 times larger than that between the $3/2^-$ and $3/2^+_{gs}$ states, indicating an extended radial component in the $1/2^+$ state wavefunction. Lifetime measurements of excited states in $^{28}$Ne are also presented. A new setup for performing Coulomb-excitation measurements based on heavy ion inelastic scattering with two targets is presented and employed to measure the $B(E2;3/2^+_{gs}\rightarrow1/2^+)$ strength in $^{27}$Ne. The method is demonstrated through a reference measurement of the $B(E2;0_{gs}^+\rightarrow2_1^+)$ of $^{30}$Mg. Combined with the lifetime measurement, the $B(M1;1/2^+\rightarrow3/2_{gs}^+)$ transition strength is extracted. The measured value is unhindered, indicating that the $1/2^+$ excited state of $^{27}$Ne is not dominated by an $s$-wave component. The electromagnetic transition strengths in $^{27}$Ne therefore indicate that the $1/2^+$ excited state may exhibit behaviors characteristic of deformed halos.In summary, this study of electromagnetic strengths demonstrates the features of nuclei in the valley of stability, and explores new aspects of nuclear structure that arise toward the edges of stability. Concurrently, Doppler-shift methods are shown to be powerful tools for investigating the structure of nuclei across the nuclear landscape.
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Title: Immigrant representation : a content analysis of media narratives of immigrants in U.K. and U.S. publications
Creator: Airgood, Bryce
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Immigration crises are not just indicative of the issues in countries that people are leaving. They represent major humanitarian crises that reflect the fears and beliefs of destination countries that include the United States, as well as the United Kingdom. The news media in both the United States and United Kingdom cover immigrants and their issues in different ways, depending on the new host country's political ideals. This research uses framing theory to analyze primary sources of the U.S...
Show moreImmigration crises are not just indicative of the issues in countries that people are leaving. They represent major humanitarian crises that reflect the fears and beliefs of destination countries that include the United States, as well as the United Kingdom. The news media in both the United States and United Kingdom cover immigrants and their issues in different ways, depending on the new host country's political ideals. This research uses framing theory to analyze primary sources of the U.S. publications The New York Times, The Washington Post and The Wall Street Journal, as well as the U.K. publications The Guardian, The Daily Telegraph and i. A qualitative content analysis of these publications revealed how immigrants are represented. It was discovered that in U.K. publications, immigrants were more likely to be represented in "politics," "immigrants as victims," or "immigrant support" frames. In U.S. publications, the articles were more likely to represent immigrants in "source of conflict," "immigration as a threat," and "immigration control" frames. This study indicates that the country of origin and that country's citizens' political ideals can affect immigrant representation in the media. -- Abstract.
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Title: Integrating a cereal rye cover crop and soybean row width with herbicides to manage Palmer amaranth in Michigan
Creator: Rogers, Kelsey Marie
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Glyphosate-resistant Palmer amaranth (Amaranthus palmeri S. Wats.) is an emerging concern for Michigan farmers. Integrating the use of cultural practices such as cover crops and narrow soybean row width may improve the control of herbicide-resistant Palmer amaranth in Michigan. In 2015 and 2016, field experiments investigated the effects of a cereal rye cover crop, including termination method, and soybean row width as cultural practices to improve Palmer amaranth control with herbicides....
Show more"Glyphosate-resistant Palmer amaranth (Amaranthus palmeri S. Wats.) is an emerging concern for Michigan farmers. Integrating the use of cultural practices such as cover crops and narrow soybean row width may improve the control of herbicide-resistant Palmer amaranth in Michigan. In 2015 and 2016, field experiments investigated the effects of a cereal rye cover crop, including termination method, and soybean row width as cultural practices to improve Palmer amaranth control with herbicides. Additional pot experiments were conducted to evaluate the effects of cereal rye stage, biomass, and termination method on Palmer amaranth emergence. Cereal rye biomass was greater in 2016 compared with 2015 due to the greater accumulation of growing degree days prior to cereal rye termination. Winter annual weeds were suppressed by more than 75% with cereal rye. However, overall Palmer amaranth emergence and control was not effected by cereal rye. In outdoor pot experiments, cereal rye suppression of Palmer amaranth emergence varied by year with the most consistent suppression with the later stage (Feekes 10.1 or later) cereal rye. In greenhouse pot experiments, total Palmer amaranth emergence was only reduced by cereal rye terminated by cutting compared with chemical termination. Planting soybean in narrow rows reduced the emergence period of Palmer amaranth in both years. Palmer amaranth was effectively controlled by both herbicide management strategies in 2015, while only the high management strategy provided season-long control in 2016. Utilizing an intensive herbicide management program and planting soybean in narrow rows provided the greatest impact on Palmer amaranth management in Michigan soybean production."--Page ii.
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Title: Salmonella typhimurium LT2 transfer and redistribution on baby spinach and cilantro during pilot-scale processing
Creator: Smolinski, Haley
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Several recent outbreaks traced to baby spinach and cilantro have been hypothesized to involve cross-contamination during washing and processing. Consequently, this study aimed to assess the redistribution of Salmonella Typhimurium LT2 during pilot-scale production of fresh-cut baby spinach and cilantro. Four inoculated:uninoculated product weight ratios (0.5:100, 1:100, 5:100, and 10:100) and three different inoculation levels (103, 101, and 10-1 CFU/g) were used with spot-inoculated red...
Show moreSeveral recent outbreaks traced to baby spinach and cilantro have been hypothesized to involve cross-contamination during washing and processing. Consequently, this study aimed to assess the redistribution of Salmonella Typhimurium LT2 during pilot-scale production of fresh-cut baby spinach and cilantro. Four inoculated:uninoculated product weight ratios (0.5:100, 1:100, 5:100, and 10:100) and three different inoculation levels (103, 101, and 10-1 CFU/g) were used with spot-inoculated red leaf lettuce serving as a colored surrogate for baby spinach and cilantro washing. Sanitizer-free wash water was used for all trials and a chlorine-based sanitizer was used at 60 ppm available chlorine only for the highest inoculation level (103 CFU/g) and the three highest weight ratios (1:100, 5:100, and 10:100). Overall, initial inoculation level had a greater impact on the amount of Salmonella-positive samples than the weight ratios examined for both commodities. The number of positive samples concurrently decreased as the initial inoculation level of the surrogate decreased. Within each inoculation level, no significant differences (P > 0.05) were found among the four product ratios. This is the first study to assess the spread of Salmonella from incoming product to baby spinach and cilantro during processing. These results will provide important data for microbial risk assessments associated with leafy greens.
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Title: Dreams of a soccer city : politics, consumption, and urban transformation in 20th century Buenos Aires
Creator: Galarza, Alex Gabriel
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This dissertation examines the Ciudad Deportiva of Club Atlético Boca Juniors, a massive stadium, sports complex, and leisure site that aimed to redevelop the city’s dilapidated riverfront in the 1960s. The directors of Boca Juniors drew state and municipal support for the Ciudad Deportiva by appealing to developmentalist ideals that prioritized public-private collaborations, consumption, and leisure space for middle class families. As Argentina’s most popular soccer club, hundreds of...
Show moreThis dissertation examines the Ciudad Deportiva of Club Atlético Boca Juniors, a massive stadium, sports complex, and leisure site that aimed to redevelop the city’s dilapidated riverfront in the 1960s. The directors of Boca Juniors drew state and municipal support for the Ciudad Deportiva by appealing to developmentalist ideals that prioritized public-private collaborations, consumption, and leisure space for middle class families. As Argentina’s most popular soccer club, hundreds of thousands of fans and supporters also invested in the project’s fundraising campaign with the belief that Boca’s stadium and facilities would contribute to the city’s modernization and symbolize national progress. Multiple democratic and military governments aided Boca’s efforts throughout a turbulent political and economic period in Argentina’s history, a signal that this kind of mass consumption and family leisure were key concerns for successive, yet divergent, political projects. The club completed most of the original planned facilities by 1970 including various sports fields, an amusement park, an aquarium, a concert pavilion, Argentina’s first drive-in movie theatre, and a social headquarters with a pool and restaurant. However, political infighting at the club, a withdrawal of public and private support, and national economic crises all contributed to Boca’s failure to construct the stadium in time for the 1978 FIFA World Cup. The municipality seized the Ciudad Deportiva in 1979 but over the next thirteen years Boca’s directors were able to regain control of the property and eventually sell it for 22 million dollars. Drawing on newspapers, sports magazines, club documents, and state sources, as well as over twenty oral histories, this dissertation makes two principal arguments. First, that soccer clubs played significant roles in shaping conceptions of neighborhood identity, gender, and class in 20th century Buenos Aires. These institutions did so in tension with their legal status as non-profit civic associations providing services to a membership base while also functioning as producers of the commercialized spectacle of professional soccer. Second, the successes and failures of the Ciudad Deportiva offer a unique perspective through which to consider the very real dreams of development that animated politics in the post-Peronist decades in Argentina. Scholars tend to focus on political polarization and instability, often obscuring the importance of notions about national and urban development embodied in the Ciudad Deportiva.
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Title: Newspaper coverage of the Flint Water Crisis : an empirical analysis to support a new model for latent environmental disasters
Creator: Tunney, Carin
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The Flint Water Crisis was a catastrophic disaster that reflects a previously, undefined pattern within human caused, slow-onset environmental crises. This pattern includes awareness, activism, governmental denial, and early signs of a legitimate, environmental hazard. This research defines the pattern as the Human Catalyst, Latent Disaster Model (HCLDM). The model is supported through review of mobilization frames, slow-onset environmental disasters, and incidents of environmental injustice....
Show moreThe Flint Water Crisis was a catastrophic disaster that reflects a previously, undefined pattern within human caused, slow-onset environmental crises. This pattern includes awareness, activism, governmental denial, and early signs of a legitimate, environmental hazard. This research defines the pattern as the Human Catalyst, Latent Disaster Model (HCLDM). The model is supported through review of mobilization frames, slow-onset environmental disasters, and incidents of environmental injustice. The model describes the predictable flow of latent disasters at various levels within society – the media, residents, government, and scientific community. This qualitative analysis of local, state, and national newspaper coverage of the Flint Water Crisis provides empirical support for the model. The analysis measures the concepts of significance, source bias, and environmental injustice through the lens of the normative theory of social responsibility. It found relationships between source-types and topics of environmental injustice consistent with a review of other incidents of latent environmental disasters. The findings help support the HCLDM as a predictive framework for study and offer a much-needed means of prediction for scholars, journalists, communities, and public health officials.
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Title: Use of water mist to reduce the risk of frost damage in tree fruits
Creator: Rijal, Ishara
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Climate variability and change have been major threats to global food security historically and will almost certainly continue to be threats in the future given the sensitivity of agricultural production systems to their surrounding environment. Recent changes in temperature and seasonality have significantly impacted commercial fruit production in the Great Lakes region. Michigan's sour cherry and apple production in 2012 was reduced by about 90% and 88%, respectively, compared to the...
Show moreClimate variability and change have been major threats to global food security historically and will almost certainly continue to be threats in the future given the sensitivity of agricultural production systems to their surrounding environment. Recent changes in temperature and seasonality have significantly impacted commercial fruit production in the Great Lakes region. Michigan's sour cherry and apple production in 2012 was reduced by about 90% and 88%, respectively, compared to the previous year's production due to a series of spring freeze events (USDA, 2013). The timing of the seasonal warm up in the spring and resulting onset of phenological development is a key factor in determining potential cold damage risk for overwintering perennial tree fruit crops, as the vulnerability of vegetation to freeze injury increases rapidly with the stage of development. Application of water prior to the onset of growth has been used in the past to delay early vegetative development of temperate tree fruit crops. Evaporative cooling associated with this approach effectively reduces plant tissue temperature, slowing the rate of growth and leaving it less vulnerable to freezing temperatures. There are several potential drawbacks, however, including consumption of large quantities of water that could increase nutrient leaching along with elevated risks of plant disease risk. This study examined the potential effectiveness of water applied as a spray mist via a new plant management technology, the solid set canopy delivery system (SSCD), to suppress tree fruit bud temperatures and delay the phenological development of the buds. There were two major portions: 1) A detailed collection of field-based phenological and physiological observations associated with the operation of a prototype SSCD cooling system and: 2) Development of a deterministic model of tree fruit bud temperature that was used to examine the potential of water-based cooling of buds in Michigan. The observational study aimed to identify the timing and discharge rate of mist applications on cherry and apple trees was carried out in a growth chamber and at five Michigan orchards (apple at St. Joseph, Charlotte, and Hillsdale, sweet cherry at SWMREC, and sour cherry at Traverse City,) during the 2014, 2015, and 2016 growing seasons with automated instrumentation to monitor and control the water mist flow rate based on environmental conditions. Water mist was applied to apple and cherry buds via the SSCD system after the end of endo-dormancy until king bloom in the non-misted buds based on ambient air temperature and relative humidity. Overall, in three years of the field study misting delayed bloom by 4-9 days in apple and 7- 11 days in cherry, all using substantially less water than that reported in earlier studies; 8.4 to 26 cm/ha in apple and 5.5 to 10.8 cm/ ha in sweet cherry. The deterministic heat transfer model of a tree fruit bud was developed with observational data from growth chamber, potted plant and field-based studies. The model was calibrated using growth chamber data and validated using potted plant and field data. In a model validation study, model simulated one-minute bud temperatures were generally found to be in good agreement with observed bud temperatures, with overall mean average differences of -0.5±0.30C (lab observations) and -0.3±0.15 0C (field observations), mean absolute differences less than 10C and R-square values of 0.80 or greater. The model was then run with ten years of hourly climate data at three locations in major fruit-producing regions of Michigan (2006-2015). Overall, the model estimated a delay in bloom of misted buds by more than a week compared to non-misted buds, which translates into a potential reduction in the frequency of damaging freeze events of 50-75 %, and decrease in freeze injury severity by 10-60 % in misted apple buds and 45-100% in misted cherry buds. Collectively, the results suggest that the spray mist technique has promise as a straightforward and effective indirect frost control strategy with relatively few environmental impacts.
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Title: Students' development and use of models to explain electrostatic interactions
Creator: Mayer, Kristin Elizabeth
Date: 2017
Collection: Electronic Theses & Dissertations
Description: The National Research Council (2012) recently published A Framework for K-12 Science Education that describes a vision for science classrooms where students engage in three dimensions—scientific and engineering practices, crosscutting concepts, and disciplinary core ideas—to explain phenomena or observations they can make about the universe around them. This vision of science instruction is a significant shift from current classroom instruction. This dissertation provides detailed examples of...
Show moreThe National Research Council (2012) recently published A Framework for K-12 Science Education that describes a vision for science classrooms where students engage in three dimensions—scientific and engineering practices, crosscutting concepts, and disciplinary core ideas—to explain phenomena or observations they can make about the universe around them. This vision of science instruction is a significant shift from current classroom instruction. This dissertation provides detailed examples of how students developed and used models to build causal explanations of phenomena. I co-taught classes that focused on having students develop and revise models of electric fields and atomic structure using a curriculum that was designed to align with the three-dimensional vision of learning. I developed case studies of eleven students from these classes. I analyzed the students’ responses and interviewed the students throughout the school year. By comparing and contrasting the analysis across the analysis of students’ interviews, I identified four themes: 1) students could apply their ideas to explain novel and abstract phenomena; 2) students struggled to connect changes in their atomic models to evidence, but ended up with dynamic models of atomic structure that they could apply to explain phenomena; 3) students developed models of atomic structure that they applied to explain phenomena, but they did not use models of electric fields in this way; and 4) too much focus on details interfered with students’ ability to apply their models to explain new phenomena. This dissertation highlights the importance of focusing on phenomena in classrooms that aim at aligning with three-dimensional learning. Students struggled to focus on specific content and apply their ideas to explain phenomena at the same time. In order to apply ideas to new context, students had to shift their focus from recalling ideas to applying the ideas they do have. A focus on phenomena allowed students to show their understanding through applying their ideas to new context. During this transition, students struggled, and in particular, had a hard time using evidence from experiments to justify the changes they made to their models of atomic structure. While the changes students made looked unproductive at times, by the end of the semester, students had developed models of atomic structure that incorporated relationships among charged components that they could apply to explain complex phenomena. Asking students to explore and evaluate their own ideas supported their development of models that they could apply to explain new context they experience in their future.
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Title: Types of feedback in peer review and the effect on student motivation and writing quality
Creator: Sloan, Christopher Colgan
Date: 2017
Collection: Electronic Theses & Dissertations
Description: In writing classrooms, peer review has been shown to have numerous practical and cognitive benefits. However, little research has been done that examines how different types of peer feedback motivate adolescent students and the effects that different types of feedback have on writing quality. While the literature has indicated that peers give each other much more positive feedback than their teachers do, the research has yielded conflicting findings on whether comments about strengths or...
Show moreIn writing classrooms, peer review has been shown to have numerous practical and cognitive benefits. However, little research has been done that examines how different types of peer feedback motivate adolescent students and the effects that different types of feedback have on writing quality. While the literature has indicated that peers give each other much more positive feedback than their teachers do, the research has yielded conflicting findings on whether comments about strengths or comments about weaknesses are more helpful. For this study high school seniors in an AP English Language and Composition class were randomly assigned to one of three treatments: a group directed only to provide comments about the strengths in the writing of their peers, a second group directed only to provide comments about weaknesses, and a "business as usual" group who were directed to provide helpful feedback (typically a mix of strength and weaknesses comments). There were no treatment group differences in students' writing quality and motivation (attributions, belongingness, and sociocognitive conflict regulation). However, there were clear indicators that suggest students saw statistically significant differences in how helpful some types of comments were perceived to be. Implications for the theory and practice of peer-based feedback in writing instruction are discussed.
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Title: Development and application of a rapid, user-friendly and inexpensive method to detect and quantify Dehalococcoides mccartyi genes in groundwater samples
Creator: Kanitkar, Yogendra Hemant
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Tetrachloroethene (PCE) and trichloroethene (TCE) are the predominant contaminants at hazardous waste sites in the United States. The remediation of these chlorinated solvents at contaminated sites frequently involves bioremediation approaches such as biostimulation or bioaugmentation. Both approaches aim at increasing the population of Dehalococcoides cells in the subsurface. It has become common to quantify the population of these microorganisms both before and during the remediation...
Show moreTetrachloroethene (PCE) and trichloroethene (TCE) are the predominant contaminants at hazardous waste sites in the United States. The remediation of these chlorinated solvents at contaminated sites frequently involves bioremediation approaches such as biostimulation or bioaugmentation. Both approaches aim at increasing the population of Dehalococcoides cells in the subsurface. It has become common to quantify the population of these microorganisms both before and during the remediation process. TaqMan probe based quantitative polymerase chain reaction (qPCR) specific to the biomarker reductive dehalogenase (RDase) genes, such as vcrA, bvcA, and tceA, is now a widely accepted molecular biological tool (MBT) for this task. To date, a wide range of qPCR protocols based on vcrA, bvcA, and tceA genes have been successful for monitoring the reductive dechlorination driven by Dehalococcoides cells. However, alternate molecular methods that are faster and cheaper may make quantification significantly easier. Loop mediated isothermal amplification (LAMP) assays were developed for the rapid and specific quantification of the RDase genes, vcrA, tceA, and bvcA in groundwater samples. As a first step, the developed LAMP assays were validated using DNA templates prepared from commercially available bioaugmenting cultures (SDC-9 and KB-1) and groundwater samples. To do this, the concentrations of Dehalococcoides mccartyi RDase genes with DNA templates obtained using LAMP were compared to concentrations obtained using qPCR on a real time thermal cycler. Additionally, the use of direct amplification was investigated. LAMP assays were then adapted for the development a field deployable kit. Here, an approach that requires only low cost laboratory equipment (a bench top centrifuge and a water bath) and significantly less time and resources compared to qPCR is described. The method involves the concentration of biomass from groundwater (without DNA extraction) and LAMP of the cell templates. The amplification products are detected by a simple visual color change (orange/green). Finally, the most probable number technique was incorporated into the altered visual detection LAMP method for the quantitative estimation of RDase gene concentrations in groundwater samples. Overall, quantification with LAMP on a real time thermal cycler was comparable to quantification with qPCR when DNA extracts prepared from SDC-9 and KB-1 or bioaugmented groundwater samples were used as templates for amplification. The LAMP assays to visually detect RDase genes, without DNA extraction or a thermal cycler, was successful to 1.8 X 105 gene copies per L for vcrA and 1.3 X 105 gene copies per L for tceA. Both values are below the threshold recommended for effective in situ dechlorination. Quantification with the MPN-LAMP assay using cell templates underestimated the concentration of RDase genes in groundwater samples by an order of magnitude compared to quantification with DNA templates and qPCR assay. Based on these results, response factors to correlate the MPN-LAMP data to estimated concentrations of RDase genes in groundwater samples are suggested. Future work should include a technology transfer of MPN-LAMP protocols to remediation practitioners.
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Title: Comparing Social Network Sites usage among African college students in the U.S. and Tanzania
Creator: Liang, Linlin
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Telecommunication infrastructure and Internet connectivity are not the universal answer to the digital divide. Telecommunication infrastructure is being built in the developing world, but most studies have yet to investigate the multiple layers and contextual factors of the digital divide, which influence technology use. This study selected Social Network Sites as an example of Information and Communications Technology due to its vital role in making social, political, and economic changes...
Show more"Telecommunication infrastructure and Internet connectivity are not the universal answer to the digital divide. Telecommunication infrastructure is being built in the developing world, but most studies have yet to investigate the multiple layers and contextual factors of the digital divide, which influence technology use. This study selected Social Network Sites as an example of Information and Communications Technology due to its vital role in making social, political, and economic changes in the developing world. This study compares the SNS use of college students from Sub-Saharan Africa region in two infrastructure and socio-cultural settings, the U.S. and Tanzania. This study broadly explores the changes in SNS use of developing country users in a less-developed telecommunication infrastructure setting like Tanzania, and those who relocated to an advanced infrastructure setting in America. The study uses interviews and a survey to investigate differences in SNS use between the two student groups, including their general SNS usage, Facebook uses, and motives to use Facebook. African students in Tanzania were more likely to use SNS for utilitarian purposes in schoolwork and professional advancement. African students in the U.S., however, mirrored their peer American students and used SNS as a social communication tool. The findings suggest that, contrary to most existing literature, free Internet accessibility does not necessarily lead to pragmatic uses of SNS. This study acknowledges the concept of usage divide and recommends that future digital divide studies include social-cultural, economic, and technological factors in their analyses. International Development researchers and practitioners should go beyond the providing of providing accessibility."--Page ii.
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Title: Dans les yeux d'un enfant : narrer le traumatisme des enfants victimes et bourreaux de la guerre civile dans la littérature d'Afrique noire francophone
Creator: Momanyi, Irene Kemunto
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Civil wars have become a common phenomenon in many African nations. Children are vulnerable and so become the most affected. The trauma caused by civil wars on children is long-term. This thesis analyzes the narration of trauma by child victims and perpetrators of civil war in black Francophone Africa. The analysis is done through two fiction novels: Ahmadou Kourouma's Allah n'est pas obligé (2002) and Emmanuel Dongala's Johnny chien méchant (2000). In both novels, the narrators are children...
Show moreCivil wars have become a common phenomenon in many African nations. Children are vulnerable and so become the most affected. The trauma caused by civil wars on children is long-term. This thesis analyzes the narration of trauma by child victims and perpetrators of civil war in black Francophone Africa. The analysis is done through two fiction novels: Ahmadou Kourouma's Allah n'est pas obligé (2002) and Emmanuel Dongala's Johnny chien méchant (2000). In both novels, the narrators are children and their narration brings into light important facts about civil wars in Africa particularly how they affect children. The first part of this thesis is dedicated to explaining civil war phenomenon as narrated by children and linking information provided by narrators with historical truths. The second part discusses children's narratives on trauma imposed by war and how this narration of trauma can be reparative to the narrators. This thesis concludes showing a new perspective that child narrators bring to the global narratives on civil wars –that of a child, a forgotten and often overlooked perspective. Children are the cradle of humanity and so the importance of this perspective cannot be overstated.
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Title: Phase sensitive measurements of ferromagnetic Josephson junctions for cryogenic memory applications
Creator: Niedzielski, Bethany Maria
Date: 2017
Collection: Electronic Theses & Dissertations
Description: A Josephson junction is made up of two superconducting layers separated by a barrier. The original Josephson junctions, studied in the early 1960's, contained an insulating barrier. Soon thereafter, junctions with normal-metal barriers were also studied. Ferromagnetic materials were not even theoretically considered as a barrier layer until around 1980, due to the competing order between ferromagnetic and superconducting systems. However, many exciting physical phenomena arise in hybrid...
Show moreA Josephson junction is made up of two superconducting layers separated by a barrier. The original Josephson junctions, studied in the early 1960's, contained an insulating barrier. Soon thereafter, junctions with normal-metal barriers were also studied. Ferromagnetic materials were not even theoretically considered as a barrier layer until around 1980, due to the competing order between ferromagnetic and superconducting systems. However, many exciting physical phenomena arise in hybrid superconductor/ferromagnetic devices, including devices where the ground state phase difference between the two superconductors is shifted by π. Since their experimental debut in 2001, so-called π junctions have been demonstrated by many groups, including my own, in systems with a single ferromagnetic layer. In this type of system, the phase of the junction can be set to either 0 or π depending on the thickness of the ferromagnetic layer. Of interest, however, is the ability to control the phase of a single junction between the 0 and π states. This was theoretically shown to be possible in a system containing two ferromagnetic layers (spin-valve junctions). If the materials and their thicknesses are properly chosen to manipulate the electron pair correlation function, then the phase state of a spin-valve Josephson junction should be capable of switching between the 0 and π phase states when the magnetization directions of the two ferromagnetic layers are oriented in the antiparallel and parallel configurations, respectively. Such a phase-controllable junction would have immediate applications in cryogenic memory, which is a necessary component to an ultra-low power superconducting computer. A fully superconducting computer is estimated to be orders of magnitude more energy-efficient than current semiconductor-based supercomputers.The goal of this work was to experimentally verify this prediction for a phase-controllable ferromagnetic Josephson junction. To address this complicated system, first, studies of junctions with only a single ferromagnetic junction were required to determine the 0-π transition thickness of that material, the decay of the critical current through the junction with thickness, and the switching field of the material. The materials studied included NiFeMo, NiFe, Ni, and NiFeCo. Additionally, roughness studies of several different superconducting base electrodes and normal metal buffer and spacer layers were performed to determine the optimum junction layers. The ferromagnetic layers used were on the order of 1-2 nm thick, so a smooth growth template is imperative to maintain continuous films with in-plane magnetizations. Lastly, single junction spin-valve samples were studied. We are not equipped to measure the phase of a single junction, but series of samples where one ferromagnetic layer is systematically varied in thickness can inform the proper thicknesses needed for 0-π switching based on relative critical current values between the parallel and antiparallel magnetic configurations. Utilizing this background information, two spin-valve samples were incorporated in a superconducting loop so that the relative phase of the two junctions could be investigated. Through this process, the first phase-controllable ferromagnetic Josephson junctions were experimentally demonstrated using phase-sensitive measurement techniques. This provided the proof of concept for the Josephson Magnetic Random Access Memory (JMRAM), a superconducting memory system in development at Northrop Grumman, with whom we collaborate on this work. Phase-controllable systems were successfully demonstrated using two different magnetic material stacks and verified with several analysis techniques.
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Title: Effect of suspect's gender on police use of physical force
Creator: Ishola, Oluwatobi Taiwo
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Police use of force has received much research attention as researchers attempt to explain various predictors of this phenomenon. This topic is of great interest to police practitioners, policy makers, researchers, scholars, and criminal justice students. Several studies have examined various predictors of this behavior, including officer education, race, experience, age, and sex. However, most of these studies focused on either the officers' or suspect's sex, while research on the interplay...
Show more"Police use of force has received much research attention as researchers attempt to explain various predictors of this phenomenon. This topic is of great interest to police practitioners, policy makers, researchers, scholars, and criminal justice students. Several studies have examined various predictors of this behavior, including officer education, race, experience, age, and sex. However, most of these studies focused on either the officers' or suspect's sex, while research on the interplay between suspect's sex and officer sex as a predictor of police use of force is lacking. Drawing on criminal threat theory and research on chivalry, this study will examine how the interplay between officer and suspect sex influences the likelihood and severity of police use of physical force. Further, given the influence of social norms on chivalry, the study will further investigate whether the presence of bystanders moderates the influence of officer and suspect sex on use of physical force. The study is based on data from the 1996-1997 (ICPSR 3172) study titled 'Understanding the use of force by and against the police in six jurisdictions in the United States'."--Page ii.
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Title: What does it mean to be literate? Designing and implementing a framework of inclusive literacy practices in a rural context
Creator: Mehta, Rohit
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Written as two interconnected articles, this dissertation study is about identifying literacy practices that are inclusive of multiple ways of being, knowing, and doing. Using these, the purpose of this study is to create a framework of inclusive literacy practices that teachers and researchers can use--implement and refine--based on their contextual needs and expectations. Driven by the rhetorical question of 'What does it means to be literate?' I use three lenses of culturally sustaining...
Show more"Written as two interconnected articles, this dissertation study is about identifying literacy practices that are inclusive of multiple ways of being, knowing, and doing. Using these, the purpose of this study is to create a framework of inclusive literacy practices that teachers and researchers can use--implement and refine--based on their contextual needs and expectations. Driven by the rhetorical question of 'What does it means to be literate?' I use three lenses of culturally sustaining pedagogy, transdisciplinary thinking, and multiliteracies to challenge normative practices that dominate acceptable ways of being, knowing, and doing in the world. To achieve this, I conducted a two-part study. In this first part, I reviewed 170 highly cited articles to compile a framework of ten literacy practices--five for learners and five for teachers--that I call Culturally sustaining, Transdisciplinary, Multiliteracies (CTM) Practices. Using this preliminary framework, I offered a set of guidelines for teachers to implement it in their classrooms. In the second part, to test the feasibility of the framework, I situated myself in an underrepresented context in multicultural education--a predominantly white rural school, and studied the affordances and constraints of the framework. I designed an embedded case study and used ethnographic methods and critical discourse analysis to analyze the framework. I found that CTM Practices framework faced four major challenges: forms of marginalization disguised in practices of social networking, distancing from experiences of other people and places, conflict between discourses of school and self, and siloed practices and definitions of literacies. I offered resolutions for each of the challenges, and found the framework to be adaptable to the rural contexts. I call for further implementation of this framework across new contexts to test its feasibility"--Pages ii-iii.
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Title: 'Poisining the viewer' : the status of drama and dramatists, paintings and painters in Renaissance England
Creator: Royston, Jennifer A.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: This dissertation examines representations of artistic professionalization in Early Modern English drama. Focused on the paragone—a series of sixteenth and seventeenth-century treatises that argued for the superiority of one artistic medium over all others—I approach drama from a sociocultural perspective, utilizing a textual archive that includes drama, antitheatrical texts, emerging artistic history, and rhetorical manuals. Bridging the theoretical gap between Early Modern literary and...
Show moreThis dissertation examines representations of artistic professionalization in Early Modern English drama. Focused on the paragone—a series of sixteenth and seventeenth-century treatises that argued for the superiority of one artistic medium over all others—I approach drama from a sociocultural perspective, utilizing a textual archive that includes drama, antitheatrical texts, emerging artistic history, and rhetorical manuals. Bridging the theoretical gap between Early Modern literary and cultural studies and contemporary revisions of theories on visual culture, this project argues for the cultural efficacy of the rising multimedia artist, the dramatist. While my interdisciplinary study builds on scholarship related to print and performance, idolatry, and art history, my project responds to current interest regarding the significance of multimedia perspectives. My research opens up traditional analyses of textual rhetoric to the realm of the visual and sheds light on the relation between aesthetics and cognitive processes in the Renaissance. Departing from previous reflections on the role of the verbal and visual in Early Modern drama, I conceptualize more specifically the tie between the rising visual and verbal artist and the ways in which this connection gets expressed in performance during England’s tumultuous religious and political Renaissance.
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