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- Title
- What counts and why? : assessment in teacher education
- Creator
- Ellis, Rebecca
- Date
- 2018
- Collection
- Electronic Theses & Dissertations
- Description
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In this dissertation I consider the ways that pre-service teachers are assessed in the middle of their program. I conducted my research at Galaxy University, a large, Midwestern university that had just completed its CAEP accreditation. Here, I collected syllabi, core assignment task descriptions and rubrics, and de-identified pre-service data submissions, as well as interviewed course instructors. I then analyzed my data to look for trends and themes, as well as with the goal to better...
Show moreIn this dissertation I consider the ways that pre-service teachers are assessed in the middle of their program. I conducted my research at Galaxy University, a large, Midwestern university that had just completed its CAEP accreditation. Here, I collected syllabi, core assignment task descriptions and rubrics, and de-identified pre-service data submissions, as well as interviewed course instructors. I then analyzed my data to look for trends and themes, as well as with the goal to better understand the choices made around assessment decisions. Throughout my research, I paid special attention to issues of fairness and how this led to tensions in the decision making process.
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- Title
- Weighting in multilevel models
- Creator
- Tong, Bing
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
-
Large-scale survey programs usually use complex sampling designs such as unequal probabilities of selection, stratifications, and/or clustering to collect data to save time and money. This leads to the necessity to incorporate sampling weights into multilevel models in order to obtain accurate estimates and valid inferences. However, the weighted multilevel estimators have been lately developed and minimal guidance is left on how to use sampling weights in multilevel models and which...
Show moreLarge-scale survey programs usually use complex sampling designs such as unequal probabilities of selection, stratifications, and/or clustering to collect data to save time and money. This leads to the necessity to incorporate sampling weights into multilevel models in order to obtain accurate estimates and valid inferences. However, the weighted multilevel estimators have been lately developed and minimal guidance is left on how to use sampling weights in multilevel models and which estimator is most appropriate.The goal of this study is to examine the performance of multilevel pseudo maximum likelihood (MPML) estimation methods using different scaling techniques under the informative and non-informative condition in the context of a two-stage sampling design with unequal probabilities of selection. Monte Carlo simulation methods are used to evaluate the impact of three factors, including informativeness of the sampling design, intraclass correlation coefficient (ICC), and estimation methods. Simulation results indicate that including sampling weights in the model still produce biased estimates for the school-level variance. In general, the weighted methods outperform the unweighted method in estimating intercept and student-level variance while the unweighted method outperforms the weighted methods for school-level variance estimation in the informative condition. In general, the cluster scaling estimation method is recommended in the informative sampling design. Under the non-informative condition, the unweighted method can be considered a better choice than the weighted methods for all the parameter estimates. Besides, the ICC has obvious effects on school-level variance estimates in the informative condition, but in the noninformative condition, it also affects intercept estimates. An empirical study is included to illustrate the model.
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- Title
- Webbed space : online feminist discourse in the fourth wave
- Creator
- Sweo, Naomi
- Date
- 2017
- Collection
- Electronic Theses & Dissertations
- Description
-
"This thesis examines the feminist online discourse community 'A Practical Wedding' and identifies four characteristics that make it a model for feminist online interaction: 1. the connection of users' online identities with their real-life selves; 2. the non-hierarchical structure of the community; 3. the productive exchanges between members; and 4. the site- and Internet-wide intertextuality. Technofeminist threads in rhetoric and composition in the late 1990's and early 2000's were mostly...
Show more"This thesis examines the feminist online discourse community 'A Practical Wedding' and identifies four characteristics that make it a model for feminist online interaction: 1. the connection of users' online identities with their real-life selves; 2. the non-hierarchical structure of the community; 3. the productive exchanges between members; and 4. the site- and Internet-wide intertextuality. Technofeminist threads in rhetoric and composition in the late 1990's and early 2000's were mostly abandoned. They deserve renewed attention, with updating based on the existence and necessity of fourth-wave feminism today. The author first describes her own origin story that led to her interest in this research. She then applies a system of virtual critical discourse analysis and resultant coding schema to four representative posts and their comment sections. This thesis concludes with a call for the creation of more communitarian, feminist spaces on the Internet with similar models of engagement to those used in 'A Practical Wedding.'"--Page ii.
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- Title
- Water content effect on nutrient removal in stormwater bioretention systems
- Creator
- Bender, Rebecca Marian
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
-
"Bioretention cells and constructed wetlands are both established best management practices (BMPs) for stormwater quality improvement. These systems vary in terms of hydraulic loading where processes such as retention, sedimentation, absorption, infiltration, filtration, phytoremediation, nitrification and denitrification remove waterborne pollutants. However, the boundary between bioretention and wetlands can be blurred when it comes to design and operational parameters, and it is therefore...
Show more"Bioretention cells and constructed wetlands are both established best management practices (BMPs) for stormwater quality improvement. These systems vary in terms of hydraulic loading where processes such as retention, sedimentation, absorption, infiltration, filtration, phytoremediation, nitrification and denitrification remove waterborne pollutants. However, the boundary between bioretention and wetlands can be blurred when it comes to design and operational parameters, and it is therefore important to explore the causes and consequences of performance variability in these systems. In an experiment to observe optimum water content for treatment pathways for ecological pollutants, five bioretention bays (2-22% water content) and fifteen bioretention columns (7-47% water content, as much as complete pore space saturation) were used to run parallel tests. Pollutant concentrations were reduced in field bays for COD, TN, and total solids (TS), although there was no difference between treatment groups in terms of any pollutant concentrations. Asclepias incarnata, Carex vulpinoidea, Scirpus validus, and Juncus effusus grew slightly taller in wetter bays, although survival of Sagittaria latifolia was uniformly poor in all treatment groups. No net pollutant removal occurred in columns, although effluent concentrations and mass export were significantly lower for near-saturation treatment groups for chemical oxygen demand (COD), nitrate, and total nitrogen (TN). There was no soil moisture level in which COD, nitrate, TN, phosphate, and TS were simultaneously improved."--Page ii.
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- Title
- WE DON’T NEED TO KNOW WHAT WE SEE : MODEST MEDIATION OF BISTABLE PERCEPTION BY KNOWLEDGE
- Creator
- Zhang, Bobicheng
- Date
- 2022
- Collection
- Electronic Theses & Dissertations
- Description
-
When faced with ambiguous visual input, an observer may have various perceptual interpre- tations even when the input remains unchanged. Indeed, such ambiguous displays can cause the observer to experience distinct perceptual interpretations in turn, unpredictably switching between them over time. Theories of such so-called multistable perception broadly fall into two categories: top-down theories that hold that perception in these cases depends strongly on higher-level cogni- tive factors...
Show moreWhen faced with ambiguous visual input, an observer may have various perceptual interpre- tations even when the input remains unchanged. Indeed, such ambiguous displays can cause the observer to experience distinct perceptual interpretations in turn, unpredictably switching between them over time. Theories of such so-called multistable perception broadly fall into two categories: top-down theories that hold that perception in these cases depends strongly on higher-level cogni- tive factors such as knowledge, and bottom-up theories which suggests more vital involvement of aspects of lower-order information processing such as local adaptation in the visual system. We evaluated whether the occurrence of perceptual reversals in the face of ambiguous input is related to the observer’s knowledge that the input is, indeed, ambiguous. We used an ambiguous animation that was designed such that subjects could report perceptual reversals without realizing the ambigu- ity. Subjects observed the animation, reported their perception, and filled out a questionnaire that assessed their knowledge of the animation’s ambiguity. We found that informed subjects reported slightly more perceptual switches than the other subjects, but that this between-group difference was very small compared to the lack of variability within each group between subjects who were aware of the ambiguity and those who were not. These findings suggests that knowledge of ambiguity can influence perception of ambiguous stimuli, but that this influence is relatively minor. This discrepancy between current findings and past work is discussed.
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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
- Voices of Mayan Women in Plaza Comunitaria : poetica y educacion desde Yucatan
- Creator
- Ceballos Zapata, Abraham
- Date
- 2017
- Collection
- Electronic Theses & Dissertations
- Description
-
This study took place in a village in Yucatan, Mexico in the context of two adult education programs in Yucatan [Plaza Comunitaria and Preparatoria Abierta]. I interacted in convivencia with bilingual (Mayan-Spanish) Yucatec Mayan women who took on the challenge of completing their formal schooling through those adult education programs. Over 3 summers (2013, 2014, 2015) I immersed myself in the community and witnessed their educational efforts. Ethnographic and convivencia methodologies ...
Show moreThis study took place in a village in Yucatan, Mexico in the context of two adult education programs in Yucatan [Plaza Comunitaria and Preparatoria Abierta]. I interacted in convivencia with bilingual (Mayan-Spanish) Yucatec Mayan women who took on the challenge of completing their formal schooling through those adult education programs. Over 3 summers (2013, 2014, 2015) I immersed myself in the community and witnessed their educational efforts. Ethnographic and convivencia methodologies (Galvan, 2015) helped generate data. I analyzed data with methodologies stemming from the humanities, in narrative (Clandinin & Connelly, 2004) and poetic analysis (Görlich, 2016; Prendergast, Leggo, & Sameshima, 2009). Through my discussion, I explore how the efforts of Yucatec Mayan women prompt educators imagine possibilities for decolonial education and inform our pedagogical practices across multiple educational settings. By focusing on the voices of rural women as poetry, I evoke the rhythms and memories of their lives in indigenous communities and in educational settings. This emerging research has taught me life and professional lessons of education on the margins. I witnessed their ethos of familia, and solidaridad as they studied together. Most importantly, they showed me how studying and being in community are inseparable. -- Abstract.
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- Title
- Vitamin E analogs exhibit antioxidative functions and inhibit production of a cytochrome P450 derived oxylipid
- Creator
- Kuhn, Matthew Joseph
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
-
Preventing and controlling disease during the transition period in cattle is the most significant health challenge facing veterinarians and farm managers. In initial studies, it was found that cattle have increased biomarkers of oxidative stress around the time of calving in addition to significant shifts in the abundance of pro-inflammatory lipid inflammatory mediators, known as oxylipids, compared to other stages of lactation. These factors, brought upon by the intense physiological shifts...
Show morePreventing and controlling disease during the transition period in cattle is the most significant health challenge facing veterinarians and farm managers. In initial studies, it was found that cattle have increased biomarkers of oxidative stress around the time of calving in addition to significant shifts in the abundance of pro-inflammatory lipid inflammatory mediators, known as oxylipids, compared to other stages of lactation. These factors, brought upon by the intense physiological shifts around the time of calving, can become detrimental and contribute to disease predisposition during the transition period in animals that do not properly adapt to such physiological changes. There is a significant need to find means to reduce oxidative stress and the production of pro-inflammatory lipid mediators at this time. One potential way is by augmenting the well-known effects of [alpha]-tocopherol with other analogs of vitamin E which have been shown in other species to have antioxidant functions and share a metabolic pathway with the pro-inflammatory oxylipid 20-HETE. Little is known about this shared metabolic pathway, specially the cytochrome P450 family 4 sub-family F member 2 enzyme, in dairy cattle. Additionally, many other cytochrome P450 enzymes which are involved in the production of other oxylipids and metabolism of fat-soluble vitamins essential to appropriate immune regulation remain mostly unexplored in cattle. A range of such cytochrome P450 enzymes was explored in both bovine tissues and common cell culture models used for oxidative stress and inflammation modeling. These data revealed which models may best represent specific cytochrome P450 metabolic pathways in vivo. A bovine mammary endothelial cell model of oxidative stress was utilized to determine the antioxidative effects of vitamin E analogs in vitro. Gamma-tocopherol was found to not only reduce the accumulation of reactive metabolites but protected cellular health by reducing apoptosis and protecting the endothelial barrier integrity. Further, [gamma]-tocopherol reduced the production of 20-HETE produced from human and bovine-kidney cytochrome P450 microsomes, likely by competitive inhibition. These data provide credence to further explore the functions of [gamma]-tocopherol and other non-[alpha]-tocopherol analogs of vitamin E in cattle. Overall, this dissertation underscores the challenges faced by dairy cattle during the transition period and highlights gaps in knowledge left to be explored regarding the production of inflammatory mediators, especially those from the cytochrome P450 pathway. Given the relative safety of feeding mixed tocopherols to dairy cattle, further efforts should be undertaken to confirm these initial safety assessments and aim to understand their potential contributions to the prevention of oxidative stress and dysfunctional inflammation during the transition period.
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- Title
- Views of the valley of despair : the photography of Jack Corn and Milton Rogovin in Appalachian coal communities (1956-1979)
- Creator
- Cepak, Anthony J.
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
-
Through extensive archival research, oral history and ethnography, this dissertation examines the coal mining photographs of photojournalist Jack Corn, repositioning his work alongside the work of noted social documentarian Milton Rogovin as being important in reshaping the visual discourse of mining in the 1950s, '60s and '70s. This dissertation argues that Corn's and Rogovin's work in Appalachia disrupted coal mining discourses popular throughout the first half of the 20th-century by...
Show moreThrough extensive archival research, oral history and ethnography, this dissertation examines the coal mining photographs of photojournalist Jack Corn, repositioning his work alongside the work of noted social documentarian Milton Rogovin as being important in reshaping the visual discourse of mining in the 1950s, '60s and '70s. This dissertation argues that Corn's and Rogovin's work in Appalachia disrupted coal mining discourses popular throughout the first half of the 20th-century by repositioning their subjects in a way that changed how society thought about mining. For Corn, the disruption in discourse came from repositioning his subjects from a perspective of celebrating the heroics of mining in the context of empire building to illustrating the devastating consequences of extracting coal from the Earth. Corn's work was generated through a combination of assigned, commissioned and independent projects that led to the creation of a significant body of work. For Rogovin, his work repositioned miners from being a faceless commodity to the coal companies, anonymously working to support the nation's vast industrial complex, to being individuals with unique identities that existed outside the confines of the mines in which they worked. By exploring the ways Corn and Rogovin disrupted popular mining discourse, this dissertation also challenges conventional notions that widespread documentation of the state of the environment in the United States began in the 1970s. Across the literature, the formation of the U.S. Environmental Protection Agency and the agency's Documerica project are often discussed as being the pivotal moment when photographic documentation of the environment began to illustrate the widespread effect of human activity on our physical world. This dissertation argues, however that, while Documerica was significant in creating a large and diverse archive of photographic evidence showing the effect industry was having on workers, family, public heath, and community, photographers such as Corn and Rogovin were approaching documentation from a similar perspective more than a decade before the project launched in 1971. While working at The Tennessean in Nashville, Tennessee, Corn departed from documenting traditional narratives of miners at work to explore the socio-economic, environmental and public health aspects of mining while covering coal communities in Appalachia beginning in the 1950s. Heavily influenced by newspaper coverage of the struggles of miners, including coverage from Corn and The Tennessean, Rogovin headed to Appalachia in 1962 and commenced what would become one of his longest and most prolific projects: documenting miners, their families and their communities. Finally, this dissertation argues that through their photography Corn and Rogovin were participating in a form of activism with the images they made being more than just documentation, but a type of visual protest against the social and environmental conditions they encountered in Tennessee, Kentucky and West Virginia. In much the same way Margaret Bourke-White, for example, gave LIFE magazine readers their first glimpses of Apartheid through her photographs of South African gold miners in the 1950s, Corn and Rogovin gave Americans living outside Appalachia a visual introduction to the human cost of a nation's growing energy consumption.
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- Title
- Video games in the present moment : flow, mind-wandering, and interoception
- Creator
- Day, Tom
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
-
Flow theory of optimal experiences was first introduced by Csikszentmihalyi in 1975. It has been debated whether an individual's attention is focused or unfocused while in the flow state. Newer research suggests that attention is intensely focused during the flow state. This coincides nicely with another thread of attentional research: interoception. Interoception is the process of listening, understanding, and interpreting signals coming from the body. The opposite of interoception is mind...
Show moreFlow theory of optimal experiences was first introduced by Csikszentmihalyi in 1975. It has been debated whether an individual's attention is focused or unfocused while in the flow state. Newer research suggests that attention is intensely focused during the flow state. This coincides nicely with another thread of attentional research: interoception. Interoception is the process of listening, understanding, and interpreting signals coming from the body. The opposite of interoception is mind-wandering. Together, interoception and mind-wandering are ways of characterizing quality of attention. This manuscript looks to link quality of attention (interoceptive awareness and mind-wandering) while playing a video game with quality of experience (flow and spatial presence). Specifically, the study links classic flow theory and virtual worlds presence (another construct associated with optimal experiences in virtual worlds) with neuroscience research on interoception and mind-wandering. The study consists of a 2 (primed for interoceptive awareness or primed for mind-wandering) by 2 (virtual reality or high-definition television) between subject design. Gaming performance and virtual reality (VR) technologies are stereotypically masculine, while interoceptive awareness is stereotypically feminine. Interaction effects of gender were considered throughout the analysis.Results confirm relationships between quality of attention and quality of experience. Specifically, interoceptive awareness while playing a video game had a positive relationship with both flow and spatial presence. The numerous significant interaction effects of gender illuminate more detailed, complex understandings. Among males, using a virtual reality headset strongly resulted in much higher performance. But among females, display modality did not appear to impact game performance. Priming for interoceptive awareness was linked to higher performance among female players and lower performance among male players. Among females, priming interoceptive awareness increased mind-wandering during gameplay in VR and decreased mind-wandering during gameplay in HDTV. This study served as a first step towards understanding relationships between quality of attention with quality of experience, indicating that the relationships may be moderated by gender.
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- Title
- Validation and application of experimental framework for the study of vocal fatigue
- Creator
- Berardi, Mark Leslie
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
-
In recent years, vocal fatigue research has been increasingly studied particularly with application to the reduction of its impact on schoolteachers and other occupational voice users. However, the concept of vocal fatigue is complex and neither well defined or well understood. Vocal fatigue seems to be highly individualized and dependent on several underlying factors or concepts. The purpose of this dissertation is to propose and support through experimentation a framework that can identify...
Show moreIn recent years, vocal fatigue research has been increasingly studied particularly with application to the reduction of its impact on schoolteachers and other occupational voice users. However, the concept of vocal fatigue is complex and neither well defined or well understood. Vocal fatigue seems to be highly individualized and dependent on several underlying factors or concepts. The purpose of this dissertation is to propose and support through experimentation a framework that can identify the factors contributing to vocal fatigue. The main hypothesis is that the change in vocal effort, vocal performance, and/or their interaction through a vocal demand (load) will implicate vocal fatigue. To test this hypothesis, three primary research questions and experiments were developed. For all three experiments vocal effort was rated using the Borg CR-100 scale and vocal performance was evaluated with five speech acoustic parameters (fundamental frequency mean and standard deviation, speech level mean and standard deviation, and smoothed cepstral peak prominence).The first research question tests whether perceived vocal effort can be measured reliably and if so, how vocal performance in terms of vocal intensity changes with a vocal effort goal. Participants performed various speech tasks at cued effort levels from the Borg CR-100 scale. Speech acoustic parameters were calculated and compared across the specific vocal effort levels. Additionally, the test-retest reliability across the effort levels for speech level was measured. Building from that experiment, the second research question was to what degree are vocal performance and vocal effort related given talker exposure to three equivalent vocal load levels. This experiment had participants performing speech tasks when presented with three different equivalent vocal load scenarios (communication distance, loudness goal, and background noise); for a given load scenario, participants rated their vocal effort associated with these tasks. Vocal effort ratings and measures of vocal performance were compared across the vocal load levels. The last research question built on the previous two and asked to what degree do vocal performance, vocal effort, and/or their interaction change given a vocal load of excess background noise (noise load) over a prolonged speaking task (temporal load). To test this, participants described routes on maps for thirty minutes in the presence of loud (75 dBA) background noise. Vocal effort ratings and measures of vocal performance were compared throughout the vocal loading task.The results indicate that elicited vocal effort levels from the BORG CR-100 scale are distinct in vocal performance and reliable across the participants. Additionally, a relationship between changes in vocal effort and vocal performance across the various vocal load levels was quantified. Finally, these findings support the individual nature of the complex relationship between vocal fatigue, vocal effort, and vocal performance due to vocal loads (via cluster and subgroup analysis); the theoretical framework captures this complexity and provides insights into these relationships. Future vocal fatigue research should benefit from using the framework as an underlying model of these relationships.
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- Title
- VISIONING THE AGRICULTURE BLOCKCHAIN : THE ROLE AND RISE OF BLOCKCHAIN IN THE COMMERCIAL POULTRY INDUSTRY
- Creator
- Fennell, Chris
- Date
- 2022
- Collection
- Electronic Theses & Dissertations
- Description
-
Blockchain is an emerging technology that is being explored by technologists and industry leaders as a way to revolutionize the agriculture supply chain. The problem is that human and ecological insights are needed to understand the complexities of how blockchain could fulfill these visions. In this work, I assert how the blockchain's promising vision of traceability, immutability and distributed properties presents advancements and challenges to rural farming. This work wrestles with the...
Show moreBlockchain is an emerging technology that is being explored by technologists and industry leaders as a way to revolutionize the agriculture supply chain. The problem is that human and ecological insights are needed to understand the complexities of how blockchain could fulfill these visions. In this work, I assert how the blockchain's promising vision of traceability, immutability and distributed properties presents advancements and challenges to rural farming. This work wrestles with the more subtle ways the blockchain technology would be integrated into the existing infrastructure. Through interviews and participatory design workshops, I talked with an expansive set of stakeholders including Amish farmers, contract growers, senior leadership and field supervisors. This research illuminates that commercial poultry farming is such a complex and diffuse system that any overhaul of its core infrastructure will be difficult to ``roll back'' once blockchain is ``rolled out.'' Through an HCI and sociotechnical system perspective, drawing particular insights from Science and Technology Studies theories of infrastructure and breakdown, this dissertation asserts three main concerns. First, this dissertation uncovers the dominant narratives on the farm around revision and ``roll back'' of blockchain, connecting to theories of version control from computer science. Second, this work uncovers that a core concern of the poultry supply chain is death and I reveal the sociotechnical and material implications for the integration of blockchain. Finally, this dissertation discusses the meaning of ``security’’ for the poultry supply chain in which biosecurity is prioritized over cybersecurity and how blockchain impacts these concerns. Together these findings point to significant implications for designers of blockchain infrastructure and how rural workers will integrate the technology into the supply chain.
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- Title
- VALIDATION OF A FELINE FEMORAL BONE SURROGATE WITH MECHANICAL AND CLINICAL EVALUATION OF FELINE ORTHOPEDIC IMPLANTS
- Creator
- Marturello, Danielle Marie
- Date
- 2021
- Collection
- Electronic Theses & Dissertations
- Description
-
A bone surrogate was developed and subsequently used to evaluate the mechanical behavior of two novel feline interlocking nails against plate controls in vitro, in an attempt to evaluate their safety and efficacy. Following testing in both torsion and 4-point bending, the I-Loc nail was evaluated in 30 clinical feline trauma cases.Fracture gap constructs were implanted with an I-Loc (3 or 4 mm), Targon (2.5 or 3.0 mm) or LCP (2.0 or 2.4 mm) and mechanically compared. Additionally, explanted...
Show moreA bone surrogate was developed and subsequently used to evaluate the mechanical behavior of two novel feline interlocking nails against plate controls in vitro, in an attempt to evaluate their safety and efficacy. Following testing in both torsion and 4-point bending, the I-Loc nail was evaluated in 30 clinical feline trauma cases.Fracture gap constructs were implanted with an I-Loc (3 or 4 mm), Targon (2.5 or 3.0 mm) or LCP (2.0 or 2.4 mm) and mechanically compared. Additionally, explanted surrogates with implant specific pilot holes were failed to assess the effect of implant removal on bone surrogate strength. Finally, a prospective clinical case series of 30 feline fractures were evaluated for time to clinical union, return to function and complications following repair using the I-Loc nail. The I-Loc 3 and 4 mm nails overall were mechanically stronger than either the Targon nails or locking plates, including explanted specimens. All cats in the clinical study were weight bearing within 2 days of surgery and reached clinical union in a mean time of 7.2 weeks. All returned to full limb function. No major complications were encountered. These studies suggest that the I-Loc may represent a safe and effective alternative to other available feline osteosynthesis options
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- Title
- Using video modeling to teach typical adolescents to interact socially with peers with ASD
- Creator
- MacFarland, Mari Cris
- Date
- 2018
- Collection
- Electronic Theses & Dissertations
- Description
-
Researchers have found that video modeling can be an effective procedure for training teachers, behavioral technicians, and paraeducators to administer evidence-based practices to children with autism spectrum disorder (Brock & Carter, 2013; Catania et al., 2009; Digennaro‐Reed, Codding, Catania, & Maguire, 2010; Lipschultz, Vladescu, Reeve, Reeve, & Dipsey, 2015; Moore & Fisher, 2007; Rosales et al., 2015; Vladescu, Carroll, Paden, & Kodak, 2012; Weldy, Rapp, & Capocasa, 2014). Video...
Show moreResearchers have found that video modeling can be an effective procedure for training teachers, behavioral technicians, and paraeducators to administer evidence-based practices to children with autism spectrum disorder (Brock & Carter, 2013; Catania et al., 2009; Digennaro‐Reed, Codding, Catania, & Maguire, 2010; Lipschultz, Vladescu, Reeve, Reeve, & Dipsey, 2015; Moore & Fisher, 2007; Rosales et al., 2015; Vladescu, Carroll, Paden, & Kodak, 2012; Weldy, Rapp, & Capocasa, 2014). Video modeling has not yet been evaluated to teach typical adolescents to deliver evidence-based practices. The purpose of the present study was to extend previous research on the use of video modeling as a training tool by teaching typical adolescents to administer naturalistic evidence-based practices to adolescents and young adults with autism spectrum disorder (ASD). This was accomplished by: (a) examining the effects of video modeling training on typical adolescents’ performance of peer mediated social interaction (PMSI), a 10-step procedure comprised of simplified behavioral practices, during roleplay with an adult actor , (b) examining the effects of video modeling training on the generalization of PMSI from an actor to adolescents with ASD, and (c) determining the social meaningfulness of video modeling training via pre- and post-intervention measures of social interaction for youth with ASD.A multiple probe design across participants was used to evaluate the effects of training via video modeling on delivery of PMSI by five typical adolescents. The dependent variable was the percentage of steps performed correctly by the typical adolescent for each step of PMSI. All participants demonstrated an immediate increase in PMSI as video modeling was systematically applied. Typical adolescents also generalized delivery to adolescents with ASD. These findings demonstrate a clear functional relation between video modeling training (VMT) and improved performance of PMSI. In addition, the present data extend the results of previous VMT research conducted with adult service providers (Catania et al., 2009; Lipschultz et al., 2015; Vladescu et al., 2012) by demonstrating similar outcomes with typical adolescents.An analysis of social interaction was conducted to ensure that teaching PMSI was likely to be of benefit to individuals with ASD. Social interaction consisted of: (a) being within 3 ft of and physically orienting toward peers, (b) interacting verbally or with gestures with one or more peers, and (c) engaging in an activity consistent with the peer hangout group. Social interaction between two youths with ASD and typical adolescent participants was evaluated within a peer mediated setting before and after VMT. Pre-intervention measures were compared to post-intervention measures. Social interaction for both youths with ASD improved following VMT.
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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
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"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
- Using Eventual Consistency to Improve the Performance of Distributed Graph Computation In Key-Value Stores
- Creator
- Nguyen, Duong Ngoc
- Date
- 2021
- Collection
- Electronic Theses & Dissertations
- Description
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Key-value stores have gained increasing popularity due to their fast performance and simple data model. A key-value store usually consists of multiple replicas located in different geographical regions to provide higher availability and fault tolerance. Consequently, a protocol is employed to ensure that data are consistent across the replicas.The CAP theorem states the impossibility of simultaneously achieving three desirable properties in a distributed system, namely consistency,...
Show moreKey-value stores have gained increasing popularity due to their fast performance and simple data model. A key-value store usually consists of multiple replicas located in different geographical regions to provide higher availability and fault tolerance. Consequently, a protocol is employed to ensure that data are consistent across the replicas.The CAP theorem states the impossibility of simultaneously achieving three desirable properties in a distributed system, namely consistency, availability, and network partition tolerance. Since failures are a norm in distributed systems and the capability to maintain the service at an acceptable level in the presence of failures is a critical dependability and business requirement of any system, the partition tolerance property is a necessity. Consequently, the trade-off between consistency and availability (performance) is inevitable. Strong consistency is attained at the cost of slow performance and fast performance is attained at the cost of weak consistency, resulting in a spectrum of consistency models suitable for different needs. Among the consistency models, sequential consistency and eventual consistency are two common ones. The former is easier to program with but suffers from poor performance whereas the latter suffers from potential data anomalies while providing higher performance.In this dissertation, we focus on the problem of what a designer should do if he/she is asked to solve a problem on a key-value store that provides eventual consistency. Specifically, we are interested in the approaches that allow the designer to run his/her applications on an eventually consistent key-value store and handle data anomalies if they occur during the computation. To that end, we investigate two options: (1) Using detect-rollback approach, and (2) Using stabilization approach. In the first option, the designer identifies a correctness predicate, say $\Phi$, and continues to run the application as if it was running on sequential consistency, as our system monitors $\Phi$. If $\Phi$ is violated (because the underlying key-value store provides eventual consistency), the system rolls back to a state where $\Phi$ holds and the computation is resumed from there. In the second option, the data anomalies are treated as state perturbations and handled by the convergence property of stabilizing algorithms.We choose LinkedIn's Voldemort key-value store as the example key-value store for our study. We run experiments with several graph-based applications on Amazon AWS platform to evaluate the benefits of the two approaches. From the experiment results, we observe that overall, both approaches provide benefits to the applications when compared to running the applications on sequential consistency. However, stabilization provides higher benefits, especially in the aggressive stabilization mode which trades more perturbations for no locking overhead.The results suggest that while there is some cost associated with making an algorithm stabilizing, there may be a substantial benefit in revising an existing algorithm for the problem at hand to make it stabilizing and reduce the overall runtime under eventual consistency.There are several directions of extension. For the detect-rollback approach, we are working to develop a more general rollback mechanism for the applications and improve the efficiency and accuracy of the monitors. For the stabilization approach, we are working to develop an analytical model for the benefits of eventual consistency in stabilizing programs. Our current work focuses on silent stabilization and we plan to extend our approach to other variations of stabilization.
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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
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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
- Use of administative claims data to design and emulate a clinical trial in acute stroke patients comparing rehabilitation at inpatient rehabilitation facilities to skilled nursing facilities
- Creator
- Simmonds, Kent P.
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
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Stroke affects nearly 800,000 people every year in the United States and is a leading cause of adult disability. After hospitalization half of stroke patients continue to require medical and rehabilitation services provided at inpatient rehabilitation facilities (IRFs) or skilled nursing facilities (SNFs). In general, IRFs provide time-intensive therapy for two to three weeks, while SNFs provide moderately intensive therapy for four- to five-weeks. There is substantial variation in the...
Show moreStroke affects nearly 800,000 people every year in the United States and is a leading cause of adult disability. After hospitalization half of stroke patients continue to require medical and rehabilitation services provided at inpatient rehabilitation facilities (IRFs) or skilled nursing facilities (SNFs). In general, IRFs provide time-intensive therapy for two to three weeks, while SNFs provide moderately intensive therapy for four- to five-weeks. There is substantial variation in the utilization of these alternative rehabilitation settings, but their relative comparative effectiveness remains uncertain. A randomized controlled trial (RCT) would provide an unbiased comparative effectiveness estimate, but the design of such a trial is complicated by several practical and ethical issues. The overarching purpose of this dissertation was to use Medicare claims data to inform the design and to emulate such a trial. In the first aim, we sought to identify patient and hospital level factors that were associated with IRF or SNF discharge and characterize the heterogeneity of hospital effects that influenced discharge to an IRF (vs. SNF). From a retrospective cohort of 145,894 stroke patients, we used multi-level multivariable models to identify several patient- and hospital- level factors that were independently associated with discharge setting. We also showed that hospitals contributed around a third of the variation in IRF (vs. SNF) discharge, but there was substantial variation in the effect that specific hospitals had on influencing IRF discharge. The second aim, was to identify a target trial population that optimized the explanatory-pragmatic balance of a subsequent RCT. To identify this population, we profiled hospitals based on their propensity to discharge stroke patients to IRFs (vs. SNFs) and inferred IRF and SNF referral networks for each hospital. The final target trial population included 44,950 patients (30.8% of the starting sample) who were treated at 441 hospitals (14.5%) and subsequently discharged to 745 IRFs (64.8%) and 5,974 SNFs (48.2%).The third aim was to emulate three alternate RCTs that compared patient outcomes at IRFs vs. SNFs. Trial #1 used the target trial population identified in Aim 2, while trials #2 and 3 excluded increasingly infrequently used IRFs and SNFs. Comparative effectiveness was estimated using a matched propensity score analysis. Overall, on a relative basis, patients treated at IRFs were between 18-35% more likely to be successfully discharged home (i.e., alive and at home for >30 days) and were between 11-15% less likely to die within one year of acute care discharge. The variation in the effect size estimates across the trials was driven by poorer outcomes among patients treated at infrequently used SNFs. Finally, we identified that a moderate sized unmeasured confounder would nullify the observed differences.In conclusion, we identified that referring hospitals are a major driver of IRF or SNF use, and that patients treated at IRFs had better outcomes (relative to SNF patients). However, our results were limited by the inability to adjust for potentially important unmeasured confounders. A pragmatic RCT would eliminate such biases and provide a more valid comparative effectiveness estimate of these two alternative rehabilitation settings.
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- Title
- Use of Recycled Aggregate Materials Characteristics in Pavement Design Analyses
- Creator
- Gheibi, Ida
- Date
- 2020
- Collection
- Electronic Theses & Dissertations
- Description
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Use of recycled materials promotes sustainability in roadway construction by reducing consumption of energy and emission of greenhouse gases associated with mining and the production of natural aggregates. Recycled asphalt pavements (RAP) and recycled concrete aggregates (RCA) have comparable characteristics to natural aggregates that are currently used in roadway base course applications. This study has developed a database for RAP and RCA materials’ characteristics including resilient...
Show moreUse of recycled materials promotes sustainability in roadway construction by reducing consumption of energy and emission of greenhouse gases associated with mining and the production of natural aggregates. Recycled asphalt pavements (RAP) and recycled concrete aggregates (RCA) have comparable characteristics to natural aggregates that are currently used in roadway base course applications. This study has developed a database for RAP and RCA materials’ characteristics including resilient modulus (Mr), California bearing ratio (CBR), gradations along with construction specifications. RAP and RCA relationships with different engineering and index properties were investigated and some trends were proposed such as higher RAP content reveals higher summary of resilient modulus (SMr), higher RCA content causes higher optimum moisture content (OMC) and lower maximum dry unit (MDU).In addition, pavement mechanistic-empirical (ME) analyses have been conducted with the material inputs collected for the database to determine whether different values of different characteristics of RCA and RAP can be used in flexible or rigid pavement designs. Results showed that Mr parameter had the highest impact on pavement distress predictions among gradations and hydraulic conductivity.
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- Title
- Urban expansion and urban environmental evaluation in Chengdu, China
- Creator
- Tao, Shiqi
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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Environmental consequences resulting from urbanization jeopardize the life quality and social welfare of urban residents. To date, studies have focused on the urban environment by using integrated assessment methods and providing one evaluation result for the whole geographic area within an administrative boundary. These studies lack consideration of spatial heterogeneity, failing to fully understand the urban environmental statuses and dynamics at the pixel scale. Therefore, this research...
Show moreEnvironmental consequences resulting from urbanization jeopardize the life quality and social welfare of urban residents. To date, studies have focused on the urban environment by using integrated assessment methods and providing one evaluation result for the whole geographic area within an administrative boundary. These studies lack consideration of spatial heterogeneity, failing to fully understand the urban environmental statuses and dynamics at the pixel scale. Therefore, this research aims to fill this gap by systematically evaluating the urban environment at every single spatial unit of urban land against the background of urban expansion in Chengdu, a megacity in western China. Guided by a proposed three-dimensional (self, neighborhood and accessibility) theoretical framework, this study uses remote sensing and GIS data and adapts the catastrophe theory to evaluate Chengdu's urban environment in a spatially explicit manner. Results from change detection of the urban area in Chengdu show a high-speed expansion from the urban center towards all directions, especially southwest during 2000-2015. Environmental assessment analysis reveals an improved urban center but degraded outskirts regarding environmental conditions. The regression analysis suggests a negative effect of rapid urban expansion on the environment, while this effect can be alleviated through better planning strategies. Therefore, it is suggested that policy makers should balance the speed of urban expansion and urban environmental planning to provide a better living environment for urban residents in Chengdu. The integration of remote sensing and urban environmental assessment can be applied to other cities in China and elsewhere around the world.
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