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- Title
- Reducing levels of medical device contamination through package redesign, seal geometry and opening technique
- Creator
- Pérez, Paula
- Date
- 2018
- Collection
- Electronic Theses & Dissertations
- Description
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Healthcare Acquired Infections (HAIs) are the cause of substantial pain and emotional stress. On any given day, 1 in every 25 patients in the US has an HAI. This has serious economic ramifications. Although the incidence of HAIs has been reduced through the implementation of varied prevention projects, work remains. Limited work has focused on indirect routes of contamination, and even fewer on packaging and handling as potential contributors. The presented work is among the first objectively...
Show moreHealthcare Acquired Infections (HAIs) are the cause of substantial pain and emotional stress. On any given day, 1 in every 25 patients in the US has an HAI. This has serious economic ramifications. Although the incidence of HAIs has been reduced through the implementation of varied prevention projects, work remains. Limited work has focused on indirect routes of contamination, and even fewer on packaging and handling as potential contributors. The presented work is among the first objectively investigating how package design and provider technique impact the sterile transfer of medical devices. Specific research goals were:1. To evaluate how package design features (inward curl, outward curl, tab design compared to a traditional, commercial pouch design) affect the likelihood of a device contacting non-sterile surfaces (the outside of the package or the hands of the provider).2. To characterize how aseptic technique (traditional vs. a modified approach) contributes to the likelihood of contact between medical devices and non-sterile surfaces during sterile transfer. 3. To develop a reliable, relatively easy and cost effective methodology that can be used to design and prototype new styles of flexible packages.4. To evaluate how peel geometry (using pouches created with the new prototyping method) impacts rates of contact between transferred devices and non-sterile surfaces.To explore goals 1, 2 and 4, a total of 136 healthcare providers were asked to present devices to a simulated sterile field. Participants’ gloved hands and the outside of test pouches were coated with a contamination simulant and participants were asked to present the contents of different pouch designs using two transfer techniques: “standard technique” where participants presented using their typical approach and a “modified technique” where participants were instructed to grab the package at the top center and transfer contents to the field using a single, fluid motion. Transferred devices were examined to verify the presence of the analyte and data was recorded in a binary fashion (yes/no) and analyzed using a generalized linear mixed model.Results indicated significant main effects of pouch design (p<0.001) and aseptic technique (P=0.0189) on rates of contact with non-sterile surfaces. Pouches designed to curl outward resulted in less contact than all other designs, this was true for both opening techniques: standard technique: (outward vs. commercial, inward and tab pouch) (14±2.5% vs. 26±3.5% (P <0.0047), 25±3.4% (P <0.0140) and 23±3.3% (P <0.0418), respectively) and modified technique (outward vs. commercial, inward and tab pouch) (8±1.8% vs. 22±3.2%, 25±3.5% and 25±3.5% respectively; all comparisons P = <0.0001) (goal 2). In support of goal 4, two geometries were created using a novel prototyping method we developed (goal 3-described within): one geometry represented a chevron pouch while the second was a rounded shape. Each of the two base geometries was modified with the addition of an extra seal intended to result in abrupt force differentials. A significant effect of geometry was indicated (P =0.0108). Specifically, the chevron geometry resulted in a higher rate of contact with non-sterile surfaces (42%±3%) than the round shaped geometry (35%±2%). Data did not support the idea that the addition of the bar intended to induce abrupt transitions in force profile had an effect on device contamination (P=0.1002).
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- Title
- Interpreting variation in restoration outcomes : functional traits shape community assembly and ecosystem functioning
- Creator
- Zirbel, Chad R.
- Date
- 2018
- Collection
- Electronic Theses & Dissertations
- Description
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Making sense of the mechanisms by which communities assemble and provide ecosystem functions is central to ecological research. The recovery of diversity and ecosystem functioning are also primary objectives of ecological restoration, yet these outcomes are often unpredictable. Restoration ecology has typically focused on reinstating particular sets of species; however, this focus on taxonomic composition limits generalization between restorations. Traits, due to their mechanistic and...
Show moreMaking sense of the mechanisms by which communities assemble and provide ecosystem functions is central to ecological research. The recovery of diversity and ecosystem functioning are also primary objectives of ecological restoration, yet these outcomes are often unpredictable. Restoration ecology has typically focused on reinstating particular sets of species; however, this focus on taxonomic composition limits generalization between restorations. Traits, due to their mechanistic and generalizable nature, may provide insights into community assembly mechanisms that move beyond this idiosyncrasy. That is, a better understanding of how traits vary among species may predict how their dispersal, establishment, and persistence affect species’ distribution and abundance among sites that vary in abiotic and biotic conditions. Functional trait-based approaches may shed light on a second major goal of restoration: understanding the functioning of ecosystems and how this is related to the diversity and composition of communities. Thus, functional traits hold great promise for interpreting, predicting, and linking the assembly and functioning of communities. This promise remains poorly realized, however, as tests linking environmental conditions, functional traits, and ecosystem functioning in restoration are rare. In turn, restored systems offer a unique test of ecological theory at the scale of ecosystems. Here I use plant functional traits to study community assembly and ecosystem functioning in grasslands undergoing restoration. My first two chapters take a trait-based approach to studying processes such as invasion and species establishment that underlie community assembly using experimentally manipulated prairie restorations. I found that the extent to which a species’ traits are adapted to the local environment, but not how much their traits overlap with species already residing at a site, influence a species’ ability to invade a novel community. Likewise, trait-environment interactions play an important role in the invasion process, further supporting the idea that having traits that are adapted to a particular environment is important for invasion success. Furthermore, considering traits independent of their environmental context is inadequate for understanding community assembly processes and trait-environment interactions determine seedling establishment rates in recent prairie restorations. My last two chapters attempt to use functional traits to link community assembly and ecosystem functioning using a set of 29 restored prairies in southwestern Michigan. I found that environmental conditions predicted community weighted mean traits, showing the value of traits for studying community assembly. In addition, I found that both functional traits and environmental conditions play an important role in shaping ecosystem functioning during restoration, and the importance of both traits and environment on functioning depends on the function of interest. Because of this, variation in environmental conditions will be necessary to promote multiple ecosystem functions across restored landscapes through management, such as prescribed fire, and by installing restorations in at sites with different environmental conditions. These results highlight the utility of functional traits for connecting community assembly and ecosystem functioning during restoration. Within this same system I also asked how different aspects of diversity (taxonomic, functional, phylogenetic), beyond individual traits, influence ecosystem functioning and an ecosystem’s ability to produce multiple functions simultaneously (ecosystem multifunctionality). I found that phylogenetic diversity and the makeup of the landscape surrounding a restoration determine ecosystem multifunctionality, though the effect of landscape is much stronger than the effect of diversity. I also find no tradeoffs between ecosystem functions that contribute to multifunctionality across sites; instead, functions are independently affected by diversity, environmental, and landscape variables. In this case, the processes that increase many individual functions—increased phylogenetic diversity and more natural landscapes—will increase multifunctionality. All of this work demonstrates that trait-based approaches to restoration can help improve our understanding of community assembly and ecosystem functioning at the ecosystem scale, explain variation in restoration outcomes, and show how restored systems can offer a unique test of ecological theory at the scale of ecosystems.
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- Title
- I do not think it means what you think it means : problem definitions and collaborative relationships in coalitions
- Creator
- Lawlor, Jennifer
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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Community psychologists frequently engage with coalitions in the study of community life. There is still little agreement on the way these organizations should be defined within the field and how they can support change. In my second chapter, I systematically review the literature within community psychology to define coalitions. I identify three types of coordination that they primarily engage in: knowledge coordination, negotiated coordination, and action coordination. Problem definition is...
Show moreCommunity psychologists frequently engage with coalitions in the study of community life. There is still little agreement on the way these organizations should be defined within the field and how they can support change. In my second chapter, I systematically review the literature within community psychology to define coalitions. I identify three types of coordination that they primarily engage in: knowledge coordination, negotiated coordination, and action coordination. Problem definition is one issue that arises in knowledge coordination among coalition members. Problem definitions can be understood as mental models and captured through using fuzzy cognitive maps. The way each individual defines the problem the group works on is often tied to collaborative behavior among coalition members. This brought me to two research questions: (1) In what ways are mental models similar or different within a coalition? (2) To what extent does mental model structure and content predict collaboration within a coalition? To address these questions, I interviewed members of a coalition to capture their mental models and surveyed them to capture their collaborative ties and demographics. To answer my first question, I assessed participants' mental models in terms of their content, structure, and function. Participants varied across each of these, but converged on a few key concepts. These findings suggest that mental modeling processes can identify differences among participants that might be used to support further dialogue among coalition members about the problem they work on. To answer my second research question, I employed an exponential random graph model using mental model similarity to predict collaborative network ties. Mental model similarity did not predict collaboration, but length of time participants have been in the coalition did emerge as a significant predictor of collaboration. These findings suggest a need for future research to assess predictors of collaboration in greater depth. I conclude with a summative discussion of the findings from each of my research questions, discussing implications for coalition practice, methods for studying them, and theories regarding coalitions.
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- Title
- EVALUATING WATER-USE EFFICIENCY IN SORGHUM-PIGEONPEA (SORGHUM BICOLOR L. MOENCH-CAJANUS CAJAN [L] MILLSP.) DIVERSIFIED CROPPING SYSTEMS IN MARGINAL AREAS OF GHANA AND MALI
- Creator
- Hayford, Princess
- Date
- 2018
- Collection
- Electronic Theses & Dissertations
- Description
-
ABSTRACTEVALUATING WATER-USE EFFICIENCY IN SORGHUM-PIGEONPEA (SORGHUM BICOLOR L. MOENCH-CAJANUS CAJAN [L] MILLSP.) DIVERSIFIED CROPPING SYSTEMS IN MARGINAL AREAS OF GHANA AND MALIByPrincess HayfordWater use efficiency (WUE) is an important determinant of crop productivity in water-limited environments where crop yield is highly dependent on rainfall. Phosphorus and nitrogen are two major nutrients limiting crop production across farming communities in West Africa; however, fertilizers are...
Show moreABSTRACTEVALUATING WATER-USE EFFICIENCY IN SORGHUM-PIGEONPEA (SORGHUM BICOLOR L. MOENCH-CAJANUS CAJAN [L] MILLSP.) DIVERSIFIED CROPPING SYSTEMS IN MARGINAL AREAS OF GHANA AND MALIByPrincess HayfordWater use efficiency (WUE) is an important determinant of crop productivity in water-limited environments where crop yield is highly dependent on rainfall. Phosphorus and nitrogen are two major nutrients limiting crop production across farming communities in West Africa; however, fertilizers are often not affordable. Sorghum-pigeonpea cropping system could be an affordable, sustainable option for smallholder farmers to improve soil fertility and increase yields. WUE of field crops (cereals, legumes) can be quite variable which complicates the extrapolation of field results to other sites. Crop simulation models (CSM) are useful tools to evaluate the agronomic and environmental performance of farming systems, aiding to extrapolate field experimentation data across environments. The objectives of this study were to determine the soil moisture distribution in the root zone of sorghum and pigeonpea, assess the effect of sole vs intercrop systems on crop yield and WUE, and simulate WUE in a sorghum-pigeonpea cropping system using APSIM. Field experiments were established for the 2015 and 2016 seasons under rain-fed conditions at four sites: two locations at the experimental field station of the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) in Samanko (Sko), Bamako; one at the field station of the Institut d’Economie Rurale (IER) in Farako (Fko), Mali; and one location at the field station of the Savanna Agricultural Research Institute (SARI) in Wa, Ghana. Sorghum was planted as a sole and an intercrop with a medium duration (MD) and a long duration (LD) pigeonpea, with a 4 replicate, randomized complete block design. Access tubes were installed in all treatments within the rows of plants, to a depth of 100 cm. Soil moisture content was monitored over the growing season in all cropping systems using Time domain reflectometry (TDR). Growth, plant biomass and yield parameters were collected and analyzed.Seasonal variation in rainfall, soil fertility, site and planting time affected phenology, grain yield and biomass production of sorghum and pigeonpea. Lack of adapted pigeonpea varieties limited grain yield, but biomass production in Mali at the adequate phosphorus fertility site SkoHP (7784 kg ha-1) was almost twice that observed at the low P site SkoLP (3400 kg ha-1). The LD variety was larger than the MD variety, and produced more grain yield. Intercropping sorghum with pigeonpea resulted in high grain yield, biomass and overall productivity in terms of land equivalent ratio. Also, plants under the ratoon system were highly productive. Soil water storage was more under sole sorghum than intercropped sorghum/pigeonpea (LD) plots due to deeper soil water extraction by pigeonpea. Cropping system significantly influenced water use (WU), with higher WU in the intercrop systems than in sole crop stands. Pigeonpea LD variety had higher WUE relative to the pigeonpea MD variety. The performance of the model in predicting crop phenology, WU and WUE under both sole and intercrop systems of sorghum were very well, with under-prediction of pigeonpea biomass and WUE. As pigeonpea is a novel crop to be grown in Ghana, adaptation of the crop to the environment needs work, and this poses a challenge to model parameterization as well. Overall these studies provided important contributions to understanding how to integrate pigeonpea into sorghum cropping systems in West Africa and the potential for multiple benefits associated with the integration of LD pigeonpea as a sorghum intercrop.
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- Title
- Hyperelastic swelling of spheres and cylinders and its generalization to elastic internally balanced materials
- Creator
- Zamani, Vahid
- Date
- 2018
- Collection
- Electronic Theses & Dissertations
- Description
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"Swelling as a notion of free volume change is typically due to some added mass procedures. We use modified constitutive laws that incorporate swelling into a continuum mechanics treatment. By incorporating local volume change (swelling) as a parametric constraint into the conventional theory of hyperelasticity it is possible to model a variety of swelling effects. We consider these effects in the study of certain boundary value problems for spherical and cylindrical finite deformations. In...
Show more"Swelling as a notion of free volume change is typically due to some added mass procedures. We use modified constitutive laws that incorporate swelling into a continuum mechanics treatment. By incorporating local volume change (swelling) as a parametric constraint into the conventional theory of hyperelasticity it is possible to model a variety of swelling effects. We consider these effects in the study of certain boundary value problems for spherical and cylindrical finite deformations. In addition to the traditional hyperelastic model, we also employ a relatively new type of constitutive treatment, termed internal balance. The theory of internally balanced materials employs energy minimization to obtain an additional balance principle to treat more complex behaviors. This is useful when conventional elastic behavior is modified by substructural reconfiguration. Hence, we also formulate our problems in the context of the internally balanced material theory for the case of cylindrical deformation where the results are compared to that of the conventional hyperelastic model. For thick spherical shells, the incompressible hyperelastic Mooney-Rivlin constitutive model allows for response to pressure-inflation that could either be globally stable (a monotonic pressure-radius graph) or could instead involve instability jumps of various kinds as pressurization proceeds. The latter occurs when the pressure-radius graph is not monotonic, allowing for a snap-through bifurcation that gives a sudden burst of inflation. Internal swelling of the material that makes up the shell wall will generally change the response. Not only does it alter the quantitative pressure-inflation relation but it can also change the qualitative stability response, allowing burst phenomena for certain ranges of swelling and preventing burst phenomena for other ranges of swelling. These issues are examined both for the case of uniform swelling for the case of a spatially varying swelling field. For cylindrical deformations, we examine the finite strain swelling of a soft solid plug within a rigid tube of circular cross section. The eventual channel wall contact as the swelling proceeds generates a confinement pressure that increases as the plug expands. We consider plug geometries that incorporate an internal channel as well as a simpler case of a solid plug. For the case of a plug with a channel, the wall contact now gives a deformation in which swelling combines axial lengthening with internal channel narrowing. Of particular interest is the closing behavior as the swelling proceeds and we treat the problem using asymptotic expansions. Finally, the same problem is examined in the context of the internal balance constitutive theory."--Pages ii-iii.
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- Title
- The role of G-protein coupled receptor kinase 2 in mucosal inflammation
- Creator
- Steury, Michael
- Date
- 2017
- Collection
- Electronic Theses & Dissertations
- Description
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G-protein coupled receptor kinases (GRKs) are a family of protein kinases comprised of seven serine/threonine kinases that were initially identified for their ability to phosphorylate G-protein coupled receptors (GPCRs). Furthermore, it has recently become evident that individual GRKs can interact in a kinase dependent or independent manner with non-receptor substrates and influence a variety of physiological functions and pathologies. This study focuses on the family member GRK2. GRK2 is...
Show moreG-protein coupled receptor kinases (GRKs) are a family of protein kinases comprised of seven serine/threonine kinases that were initially identified for their ability to phosphorylate G-protein coupled receptors (GPCRs). Furthermore, it has recently become evident that individual GRKs can interact in a kinase dependent or independent manner with non-receptor substrates and influence a variety of physiological functions and pathologies. This study focuses on the family member GRK2. GRK2 is expressed ubiquitously throughout the body and in addition to phosphorylating and regulating GPCR function, GRK2 is able to phosphorylate and/or interact with a large interactome of cellular proteins in a tissue - and context - specific manner. This combination of canonical and non- canonical roles of GRK2 is now attributed to a multitude of vital physiological functions including: cell migration, proliferation, metabolism, angiogenesis, and insulin resistance. This vast array of influence makes GRK2 a popular target of study for both diagnostic opportunities as well as therapeutic interventions and while GRK2 has been extensivelystudied in cardiac and immune cells its role in the intestine and the intestinal epithelium is not well understood.Inflammatory bowel disease is characterized by damage to the intestinal epithelial barrier resulting in increased permeability and the resultant dissemination of the commensal microbiota. This translocation of the luminal contents into the lamina propria constantly stimulates the immune system leading to its hyper-activation and eventual damage to the intestine. Inflammatory bowel disease is associated with increases in inflammatory cytokine production, namely TNFα and this study was performed to investigate the regulation of GRK2 on TNFα signaling in the intestinal epithelial cells and in a larger context its role in the regulation in onset and pathogenesis of acute colitis. We found that decreasing the levels of GRK2 in human epithelial cells influenced the induction of ROS production by TNFα that influences ERK1/2 signaling and the production of MMP9 to influence wound closure both in culture and in animal models. Furthermore, mice heterozygous for GRK2 were markedly protected from the onset and pathogenesis of acute DSS-induced colitis in the absence of any alterations in immune infiltration. Myeloid specific knockout studies showed this population to be in part responsible for the protection seen in the whole body knockout. Together these studies suggest that GRK2 may serve as a novel therapeutic option for the treatment of colitis.
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- Title
- Change of heart : the influence of the external environment on academic library collections
- Creator
- Dean, Jennifer Lynn
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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"The academic library, affectionately referred to as the heart of the campus due to its physical and metaphorical centrality to academic life, has undergone significant change since the 1990s. The advent of the internet and rapid advances in technology have wrought wide-ranging change in academic libraries. Although the library literature confirms the changing environment surrounding academic libraries and librarians, many library papers are individual accounts of processes and best practices...
Show more"The academic library, affectionately referred to as the heart of the campus due to its physical and metaphorical centrality to academic life, has undergone significant change since the 1990s. The advent of the internet and rapid advances in technology have wrought wide-ranging change in academic libraries. Although the library literature confirms the changing environment surrounding academic libraries and librarians, many library papers are individual accounts of processes and best practices with little connection to the literature on organizational change. This dissertation study focuses on changes in academic library collections and collection development and acquisitions (CDA) practices. The collection is perceived by administrators, faculty, students, and librarians themselves as centrally important to the library and the institution. Although the library collection is essential to teaching, learning, and research, it has received little attention in the higher education literature. I interviewed 14 librarians at two regional, public, research institutions in Michigan. Using Resource Dependence Theory (RDT) to frame this study and analyze the results, I examined the role of the external environment and its influence on the strategies academic librarians used to perform CDA work. Participants identified funding, curriculum, faculty, students, administrators, and vendors and publishers as environmental influences, indicating that the library functioned as a separate organization within its institution. Librarians employed a variety of strategies to manage environmental constraints, maintain balance, and preserve library and academic culture, including information gathering, communication, budgetary management, and relying on collection use data."--Page ii.
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- Title
- Discourse and grammatical cues in the acquisition of Spanish pronouns
- Creator
- Forsythe, Hannah
- Date
- 2018
- Collection
- Electronic Theses & Dissertations
- Description
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"From an acquisition standpoint, personal pronouns are particularly interesting to study because they are a perfect encapsulation of the problem faced by the language learner: how to coordinate information from multiple levels of representation while still in the process of acquiring those representations. Pronoun interpretation is influenced by constraints at every level of representation, from phonology to discourse, and acquisition at one level can constrain the path of acquisition at...
Show more"From an acquisition standpoint, personal pronouns are particularly interesting to study because they are a perfect encapsulation of the problem faced by the language learner: how to coordinate information from multiple levels of representation while still in the process of acquiring those representations. Pronoun interpretation is influenced by constraints at every level of representation, from phonology to discourse, and acquisition at one level can constrain the path of acquisition at other levels. This dissertation focuses on the interaction between the levels of morphosyntax and discourse during development, specifically, how the acquisition of person and number features relates to the acquisition of discourse relations: the semantic relations between events and states in a discourse. Person and number cues provide bottom-up information about who the referent of a pronoun can and cannot be, while discourse relations provide top-down information about which referents are likely to be the targets of pronominal reference. The question for acquisition is very simple: Do children proceed bottom up or top down? Focusing on preschoolers acquiring Mexican Spanish, a language with abundant person and number cues, we divide the problem into three parts: Q1.Which person and number cues are children sensitive to, and when? Q2.Which discourse cues are children sensitive to, and when? Q3.How do children integrate these cues together at different ages? Person and number cues: In picture-selection and act-out tests, children show early comprehension of 1st and 2nd person morphology but inconsistent behavior in the 3rd person. Children are aware that 3rd person pronouns select a referent or antecedent from the preceding physical or linguistic discourse, but they fail to consistently choose referents compatible with their person and number morphology. Discourse cues: Adults use a combination of discourse relations and pronominal form (null vs. overt subjects) to interpret grammatically ambiguous subject pronouns. Children under 4 ½ show sensitivity to discourse relations, while children over 4 ½ show sensitivity to the null/overt contrast. Integration: Four picture-selection experiments examine children's sensitivity to different discourse relations, first in isolation and then in combination with person and number cues. When cues to the Parallel discourse relation appear in isolation, children show weak sensitivity at best. However, when parallelism and number cues are combined, parallelism has a facilitating effect on the comprehension of number by children ages 4 ½ and up. Moreover, this facilitating effect coincides with a jump in children's overall sensitivity to number morphology. When cues to the temporal discourse relation Occasion appear in isolation, we again find little evidence of sensitivity. However, when temporal and person cues are combined, temporal cues have a facilitating effect on the comprehension of 3rd person features by children ages 4 ½ and up. Moreover, this facilitating effect coincides with a jump in children's overall sensitivity to 3rd person morphology. In other words, we see a correlation between sensitivity to discourse relations (Parallel, Occasion) and adult-like use of person and number morphology. Do children proceed bottom-up or top-down? Children's difficulty with at least some person and number cues, plus their early sensitivity to at least some discourse cues, rules out a strictly bottom-up hypothesis. However, their early adult-like use of 1st and 2nd person morphology also rules out a strict topdown hypothesis. Instead, we come down in favor of a weak version of the top-down hypothesis. Specifically, we claim that while children have early representations of the full set of person and number features, this knowledge is more difficult to deploy when interpreting semantically and morphologically underspecified pronouns (3rd person singular and 3rd person plural), and that discourse sensitivity facilitates the interpretation of such pronouns."--Pages ii-iii.
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- Title
- Rural migrant Hausa girls, a community faith-based school, and environmental change in Sokoto, northwest Nigeria
- Creator
- Idris, Abubakar
- Date
- 2019
- Collection
- Electronic Theses & Dissertations
- Description
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Engaging with feminist and post-colonial theories to examine the ways in which gender identity, gender power, and gender relations are enacted, this dissertation examines a shift that has recently been occurring in the education of rural Hausa girls, whose families are increasingly sending them to residential Qur'anic schools in metropolitan Sokoto rather than to government schools. At the root of this change, it identifies Hausa parents' desire to entrench traditional gender roles grounded...
Show moreEngaging with feminist and post-colonial theories to examine the ways in which gender identity, gender power, and gender relations are enacted, this dissertation examines a shift that has recently been occurring in the education of rural Hausa girls, whose families are increasingly sending them to residential Qur'anic schools in metropolitan Sokoto rather than to government schools. At the root of this change, it identifies Hausa parents' desire to entrench traditional gender roles grounded in the cultural values and principles of Islamic religious ideology. To fulfill this aim, however, these parents must disrupt another aspect of the existing system of traditional gender roles, in which girls disproportionately farm and perform household duties. Moreover, it identifies the driving force of such disruption as Hausa fathers, who as the major decision-makers in their households are often making these schooling choices on their daughters' behalf in the face of sharp opposition from their wives. As a result, Hausa mothers must adjust to the loss of a major source of household labor, among other effects of the absence of their daughters from their homes. In other words, families lose their daughters' labor contributions when they leave their rural communities to go to Qur'anic schools in urban centers like Sokoto. The dissertation concludes by drawing the attention of the Nigerian government to its new data on the cultural and religious issues that should be considered by policymakers seeking to bring free universal primary and secondary education to under-served rural Hausa children and families in Northern Nigeria.
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- Title
- Robust global motion compensation and its applications
- Creator
- Safdarnejad, Seyed Morteza
- Date
- 2017
- Collection
- Electronic Theses & Dissertations
- Description
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This thesis presents algorithms for robust global motion compensation (GMC). GMC algorithms are used to remove camera motion and transform the video such that in the resultant video, the background appears static and the only motion rises from foreground objects. Many computer vision algorithms are tailored for static camera, and using GMC, it is possible to apply these algorithms on videos from moving cameras. For instance, motion-based video analysis is strongly affected by camera motion....
Show moreThis thesis presents algorithms for robust global motion compensation (GMC). GMC algorithms are used to remove camera motion and transform the video such that in the resultant video, the background appears static and the only motion rises from foreground objects. Many computer vision algorithms are tailored for static camera, and using GMC, it is possible to apply these algorithms on videos from moving cameras. For instance, motion-based video analysis is strongly affected by camera motion. If camera motion is not compensated, it interferes with the motion of interest, such as motion of human, and renders the analysis problem to be more challenging.Generally, in sequential schemes, GMC estimates the homography transformation between two consecutive frames by matching keypoints on the frames, and maps the second frame to a global coordinate. Then, by accumulating these transformations, a composite transformation is calculated which maps each frame to the global coordinate. However, existing GMC algorithms are sensitive to existence of foreground motion and fail easily in the case of considerable foreground motion or ambiguous and low texture background.To address the challenges in GMC, first, we propose a Robust Global Motion Compensation (RGMC) algorithm which explicitly suppresses the foreground effect and utilizes a comprehensive probabilistic verification model to find the best mappings between consecutive frames. Despite the robustness offered by RGMC, we further identified the problem of temporal drift of the estimation, due to accumulation of errors in estimation of mappings between consecutive coordinates. Furthermore, to address the issues of sequential GMC, we propose a Temporally Robust Global Motion Compensation (TRGMC) algorithm which by joint alignment of input frames, estimates accurate and temporally consistent transformations to the global coordinates. Joint alignment not only leads to the temporal consistency of GMC, but also improves GMC stability by using redundancy of the information.Many applications can benefit from a reliable and accurate GMC algorithm. We first briefly look into these applications. Then, among the many applications, we further investigate the problem of sequence alignment, and propose an alignment algorithm for non-overlapping sequences, enabled by performance of TRGMC. Given the transformation to a global coordinate, offered by TRGMC, and capability of background reconstruction using TRGMC result, we are able to align sequences even if the spatial overlap between the sequences is minimal or nonexistent. To this end, we first spatially align the sequences such that extrapolated backgrounds are aligned well and trajectory of moving objects are spatially smooth in the global coordinate. Next, we temporally align the sequences based on the smoothness of spatio-temporal trajectory of moving objects across field of view of different cameras.
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- Title
- School board decision making practices
- Creator
- Beard, Nicole R.
- Date
- 2017
- Collection
- Electronic Theses & Dissertations
- Description
-
ABSTRACTSCHOOL BOARD DECISION MAKING PRACTICESByNicole R. BeardThe purpose of this study was to examine the way in which school boards use data when making decisions, specifically their orientations, perceptions, concerns and priorities around data. This study sought to understand how school boards use data when setting or tracking progress toward goals and aimed following the process of board use of data to discern how they create knowledge upon which to base their decisions and direct...
Show moreABSTRACTSCHOOL BOARD DECISION MAKING PRACTICESByNicole R. BeardThe purpose of this study was to examine the way in which school boards use data when making decisions, specifically their orientations, perceptions, concerns and priorities around data. This study sought to understand how school boards use data when setting or tracking progress toward goals and aimed following the process of board use of data to discern how they create knowledge upon which to base their decisions and direct subsequent action. Three school boards were selected based on specific criteria that were found beneficial to the study’s purpose and goal. Participants were sent an online survey to complete, as well as observed during board meeting and committee meetings. In addition, each superintendent and two school board members from each district participated in face to face interviews regarding their views on the role of data when making decisions. The results of this research study brought into focus how organizations such as these learn about data and put this knowledge into action in the form of decision making. As school board members examine data, they take part in an information sharing cycle that transforms the data into contextually relevant information that in turn becomes knowledge. This knowledge can be acted upon and enables school boards to validate their reasons for the decisions made as a collective body. Learning about this cycle can be helpful in helping community members and other stakeholders better understand the level of analysis that takes place when board members make decisions.
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- Title
- Measurement of isobaric analogue resonances of 20742077Ar with the active-target time projection chamber
- Creator
- Bradt, Joshua William
- Date
- 2017
- Collection
- Electronic Theses & Dissertations
- Description
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While the nuclear shell model accurately describes the structure of nuclei near stability, the structure of unstable, neutron-rich nuclei is still an area of active research. One region of interest is the set of nuclei near N=28. The shell model suggests that these nuclei should be approximately spherical due to the shell gap predicted by their magic number of neutrons; however, experiments have shown that the nuclei in this region rapidly become deformed as protons are removed from the...
Show moreWhile the nuclear shell model accurately describes the structure of nuclei near stability, the structure of unstable, neutron-rich nuclei is still an area of active research. One region of interest is the set of nuclei near N=28. The shell model suggests that these nuclei should be approximately spherical due to the shell gap predicted by their magic number of neutrons; however, experiments have shown that the nuclei in this region rapidly become deformed as protons are removed from the spherical 48Ca. This makes 46Ar a particularly interesting system as it lies in a transition region between 48Ca and lighter isotones that are known to be deformed.An experiment was performed at the National Superconducting Cyclotron Laboratory (NSCL) to measure resonant proton scattering on 46Ar. The resonances observed in this reaction correspond to unbound levels in the 47K intermediate state nucleus which are isobaric analogues of states in the 47Ar nucleus. By measuring the spectroscopic factors of these states in 47Ar, we gain information about the single-particle structure of this system, which is directly related to the size of the N=28 shell gap. Four resonances were observed: one corresponding to the ground state in 47Ar, one corresponding its first excited 1/2- state, and two corresponding to 1/2+ states in either 47Ar or the intermediate state nucleus. However, only a limited amount of information about these states could be recovered due to the low experimental statistics and limited angular resolution caused by pileup rejection and the inability to accurately reconstruct the beam particle track.In addition to the nuclear physics motivations, this experiment served as the radioactive beam commissioning for the Active-Target Time Projection Chamber (AT-TPC). The AT-TPC is a new gas-filled charged particle detector built at the NSCL to measure low-energy radioactive beams from the ReA3 facility. Since the gas inside the detector serves as both the tracking medium and the scattering target, reactions are measured over a continuous range of energies with near-4π solid angle coverage. This experiment demonstrated that tracks recorded by the AT-TPC can be reconstructed to a good resolution, and it established the feasibility of performing similar experiments with this detector in the future.
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