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Title: MEASURING AND MODELING THE EFFECTS OF SEA LEVEL RISE ON NEAR-COASTAL RIVERINE REGIONS : A GEOSPATIAL COMPARISON OF THE SHATT AL-ARAB RIVER IN SOUTHERN IRAQ WITH THE MISSISSIPPI RIVER DELTA IN SOUTHERN LOUISIANA, USA.
Creator: Kadhim, Ameen Awad
Date: 2018
Collection: Electronic Theses & Dissertations
Description: There is a growing debate among scientists on how sea level rise (SLR) will impact coastal environments, particularly in countries where economic activities are sustained along these coasts. An important factor in this debate is how best to characterize coastal environmental impacts over time. This study investigates the measurement and modeling of SLR and effects on near-coastal riverine regions. The study uses a variety of data sources, including satellite imagery from 1975 to 2017, digital...
Show moreThere is a growing debate among scientists on how sea level rise (SLR) will impact coastal environments, particularly in countries where economic activities are sustained along these coasts. An important factor in this debate is how best to characterize coastal environmental impacts over time. This study investigates the measurement and modeling of SLR and effects on near-coastal riverine regions. The study uses a variety of data sources, including satellite imagery from 1975 to 2017, digital elevation data and previous studies. This research is focusing on two of these important regions: southern Iraq along the Shatt Al-Arab River (SAR) and the southern United States in Louisiana along the Mississippi River Delta (MRD). These sites are important for both their extensive low-lying land and for their significant coastal economic activities. The dissertation consists of six chapters. Chapter one introduces the topic. Chapter two compares and contrasts bothregions and evaluates escalating SLR risk. Chapter three develops a coupled human and natural system (CHANS) perspective for SARR to reveal multiple sources of environmental degradation in this region. Alfa century ago SARR was an important and productive region in Iraq that produced fruits like dates, crops, vegetables, and fish. By 1975 the environment of this region began to deteriorate, and since then, it is well-documented that SARR has suffered under human and natural problems. In this chapter, I use the CHANS perspective to identify the problems, and which ones (human or natural systems) are especially responsible for environmental degradation in SARR. I use several measures of ecological, economic, and social systems to outline the problems identified through the CHANS framework. SARR has experienced extreme weather changes from 1975 to 2017 resulting in lower precipitation (-17mm) and humidity (-5.6%), higher temperatures (1.6 C), and sea level rise, which are affecting the salinity of groundwater and Shatt Al Arab river water. At the same time, human systems in SARR experienced many problems including eight years of war between Iraq and Iran, the first Gulf War, UN Security Council imposed sanctions against Iraq, and the second Gulf War. I modeled and analyzed the regions land cover between 1975 and 2017 to understand how the environment has been affected, and found that climate change is responsible for what happened in this region based on other factors. Chapter four constructs and applies an error propagation model to elevation data in the Mississippi River Delta region (MRDR). This modeling both reduces and accounts for the effects of digital elevation model (DEM) error on a bathtub inundation model used to predict the SLR risk in the region. Digital elevation data is essential to estimate coastal vulnerability to flooding due to sea level rise. Shuttle Radar Topography Mission (SRTM) 1 Arc-Second Global is considered the best free global digital elevation data available. However, inundation estimates from SRTM are subject to uncertainty due to inaccuracies in the elevation data. Small systematic errors in low, flat areas can generate large errors in inundation models, and SRTM is subject to positive bias in the presence of vegetation canopy, such as along channels and within marshes. In this study, I conduct an error assessment and develop statistical error modeling for SRTM to improve the quality of elevation data in these at-risk regions. Chapter five applies MRDR-based model from chapter four to enhance the SRTM 1 Arc-Second Global DEM data in SARR. As such, it is the first study to account for data uncertainty in the evaluation of SLR risk in this sensitive region. This study transfers an error propagation model from MRDR to the Shatt al-Arab river region to understand the impact of DEM error on an inundation model in this sensitive region. The error propagation model involves three stages. First, a multiple regression model, parameterized from MRDR, is used to generate an expected DEM error surface for SARR. This surface is subtracted from the SRTM DEM for SARR to adjust it. Second, residuals from this model are simulated for SARR: these are mean-zero and spatially autocorrelated with a Gaussian covariance model matching that observed in MRDR by convolution filtering of random noise. More than 50 realizations of error were simulated to make sure a stable result was realized. These realizations were subtracted from the adjusted SRTM to produce DEM realizations capturing potential variation. Third, the DEM realizations are each used in bathtub modeling to estimate flooding area in the region with 1 m of sea level rise. The distribution of flooding estimates shows the impact of DEM error on uncertainty in inundation likelihood, and on the magnitude of total flooding. Using the adjusted DEM realizations 47 ± 2 percent of the region is predicted to flood, while using the raw SRTM DEM only 28% of the region is predicted to flood.
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Title: Enteric glial cell regulation of oxidative stress and immune homeostasis during gastrointestinal inflammation
Creator: Brown, Isola Angella Maria
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Gastrointestinal (GI) motility dysfunction is a debilitating feature that presents asa symptom in a number of conditions. These include primary GI disorders likeinflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) but alsosecondary conditions like diabetes mellitus, Parkinson's Disease and simply as aconsequence of physiological aging. Although as many as 1 in 4 persons worldwide areaffected by GI motility dysfunction, there is a significant lack of safe and effective drugs,due...
Show moreGastrointestinal (GI) motility dysfunction is a debilitating feature that presents asa symptom in a number of conditions. These include primary GI disorders likeinflammatory bowel disease (IBD) and irritable bowel syndrome (IBS) but alsosecondary conditions like diabetes mellitus, Parkinson's Disease and simply as aconsequence of physiological aging. Although as many as 1 in 4 persons worldwide areaffected by GI motility dysfunction, there is a significant lack of safe and effective drugs,due to a gap in the knowledge regarding the cellular mechanisms that contribute to GImotility dysfunction.Normal gut function is controlled by the enteric nervous system (ENS), anintrinsic neuronal network comprised of enteric neurons and supporting glial cells, whichis embedded within the walls of the GI tract. Death of enteric neurons, and the resultingdisruption of this neuronal network, contributes to motility dysfunction duringinflammation. In this dissertation, we investigate how increased oxidative stress andimbalanced immune homeostasis, key factors associated with GI inflammation,contribute to enteric neuropathy. We hypothesize a role for enteric glial cells, which arecapable of modulating ENS oxidative stress, and also have an importantimmunomodulatory role in the ENS.The work in this dissertation used a combination of transgenic animal strains,immunohistochemistry (IHC), pharmacological modulators, Ca2+ imaging and in situ andin vivo models of colitis to investigate our hypothesis. We show a key role for entericglial regulation of oxidative stress in mediating neuronal loss. During inflammation,purinergic activation of enteric glia drives enteric neuron death through a pathway thatrequires glial nitric oxide (NO) production and glial Cx43 hemichannels anddemonstrates a novel pathogenic role for enteric glia. Further, glial production of theantioxidant reduced glutathione (GSH) is necessary for neuronal survival in situ,although whole body GSH depletion has novel protective roles against key features ofmurine colitis. Mice with disrupted in T cell signaling of the anti-inflammatory cytokineTGFβ had altered GI function, immune homeostasis and glial activation at the level ofthe myenteric plexus. Lastly, we show that key pro-inflammatory mediators differentiallyalter glial Cx43 channel opening in quiescent versus activated enteric glia.Our data provide new evidence for an active role for enteric glial cells in GI(patho)physiology. Specifically, we demonstrate that enteric glia are involved inmediating the effects of oxidative stress and immune imbalance during GI inflammationand propose novel targets for the development of improved therapeutics to treat GImotility dysfunction.
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Title: A study of the grain growth of a low carbon steel
Creator: Percy, James W.
Date: 1926
Collection: Electronic Theses & Dissertations

Title: The role of evidence in animal welfare science and standards : an ethical analysis
Creator: List, Monica
Date: 2019
Collection: Electronic Theses & Dissertations
Description: The development of the field of animal welfare science in recent decades, together with growth in public interest and ethical concerns for the welfare of animals has arguably led to an increase in regulation, both public and private, in the production and use of farmed animals. Animal welfare regulation, in the form of legislation, directives, industry guidelines and private standards is characterized by its reliance on scientific evidence to justify the conditions under which farmed animals...
Show moreThe development of the field of animal welfare science in recent decades, together with growth in public interest and ethical concerns for the welfare of animals has arguably led to an increase in regulation, both public and private, in the production and use of farmed animals. Animal welfare regulation, in the form of legislation, directives, industry guidelines and private standards is characterized by its reliance on scientific evidence to justify the conditions under which farmed animals should be bred, raised, transported, and slaughtered. One of the important roles scientific evidence plays in discussions around the regulation of farmed animal welfare is providing a seemingly ethically neutral understanding of how animals should be treated, in other words, it sidesteps ethical arguments for the treatment of animals, using science as a justification. However, per the dominant philosophy of science discourse on the role of values in science, no science can be considered value-free, and furthermore, there are acceptable roles for social and ethical values in scientific practice. These roles are not just acceptable, but necessary for the direction, interpretation, and application of science. This work argues that: a) given the broad range of ethical views regarding how we should treat animals, animal welfare science provides robust and credible guidance; b) furthermore, that animal welfare science is not only inspired or informed by animal ethics concepts and frameworks, but also has embedded social/ethical and cognitive values throughout; c) thus, in order to fulfil its purpose as a socially mandated science, animal welfare science should engage in intentional processes to determine adequate roles for various kinds of values underlying all stages of the scientific process and the interpretation and implementation of findings. This intentional examination of the role of values can be supported by more effective interdisciplinary collaboration. While animal welfare science is characterized in part by its interdisciplinary nature, it is important to question to what extent the research is truly interdisciplinary in the sense of fostering epistemic integration. Philosophical tools and analyses, beyond the typical uses of ethical frameworks as a starting point, can be valuable in facilitating effective interdisciplinary work, leading to a better understanding of the normative dimensions of animal welfare science.
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Title: Reinvestigating the beauty match up hypothesis and social comparison in food advertisements
Creator: Mundel, Juan
Date: 2018
Collection: Electronic Theses & Dissertations
Description: "The use of attractive models as a means to grab consumers' attention and influence their product evaluations and purchase intentions is a common occurrence among advertisers. Research shows that recurrent exposure to ads featuring models with idealized bodies can lead to negative self-evaluations, development of eating disorders, and depression, among other negative outcomes. Given their greater likelihood to express discontent with their bodies when compared to their male counterparts, most...
Show more"The use of attractive models as a means to grab consumers' attention and influence their product evaluations and purchase intentions is a common occurrence among advertisers. Research shows that recurrent exposure to ads featuring models with idealized bodies can lead to negative self-evaluations, development of eating disorders, and depression, among other negative outcomes. Given their greater likelihood to express discontent with their bodies when compared to their male counterparts, most of the literature on this issue has focused on women as the population under study. However, a third of all individuals suffering from eating disorders in the U.S. are males. This dissertation explores how males evaluate models featured in snack food advertisements when their bodies conform (or not) with advertising industry norms, and the effects of the pairing of different models with products perceived to be healthy (vs. unhealthy) on participants' evaluations of the self, the product, and the ad. Results showed a significant interaction between exposure to idealized bodies in advertisements and upward social comparison, indicating that respondents with higher social comparison scores had more negative evaluations of the ads. Exposure to ads with idealized bodies predicts participants' engagement in upward social comparison. Further, our results show that upward social comparison was a significant predictor of body dissatisfaction. Yet, overall participants had better evaluations of the ads when presented with unhealthy foods and models with idealized bodies, which stresses the need for guidelines for model casting in advertising."--Page ii.
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Title: Integrated pest management strategies for control of potato early die in Michigan potato systems
Creator: Cole, Emilie
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Root lesion nematodes (Pratylenchus penetrans) in conjunction with the fungal pathogen Verticillium dahliae create the disease complex, potato early die, which can drastically reduce potato (Solanum tuberosum L.) yields. In Michigan, this disease complex is often managed using broad-spectrum soil fumigants such as methyl bromide, metam sodium and 1,3- dichloropropene, which can be harmful to applicators as well as soil and environmental health. Since the phase-out of methyl bromide in 2005,...
Show moreRoot lesion nematodes (Pratylenchus penetrans) in conjunction with the fungal pathogen Verticillium dahliae create the disease complex, potato early die, which can drastically reduce potato (Solanum tuberosum L.) yields. In Michigan, this disease complex is often managed using broad-spectrum soil fumigants such as methyl bromide, metam sodium and 1,3- dichloropropene, which can be harmful to applicators as well as soil and environmental health. Since the phase-out of methyl bromide in 2005, alternative control tactics to soil fumigants have become increasingly important to potato growers. In this thesis I investigated the use of (1) manures and manure-based composts and (2) non-fumigant nematicides and fungal-based biocontrols and their efficacy in reducing potato early die incidence. In laboratory trials, poultry manure and a blend of poultry and dairy manure compost (Layer Ash Blend) provided significant control of root lesion nematodes with 0% survivorship at rates of 5% (vol/vol) or higher. In field trials, I did not observe significant (P < 0.05) reductions in nematode populations regardless of treatment but did see a reduction in germinating V. dahliae microsclerotia in plots treated with poultry manure. Of the nematicides tested, Salibro treatments significantly reduced root lesion nematode and V. dahliae populations. From this research, it is clear that non-fumigant alternatives are possible for Michigan potato growers.
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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: 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: 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: Curriculum and career development events : preparation strategies for knowledge and skill transfer in the Michigan environmental skills CDE
Creator: Pauley, Catlin M.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: School-based agricultural education (SBAE) offers copious opportunities through the classroom and career development events (CDEs), among other contexts, to prepare students with knowledge and skills related to agriculture, food, and natural resources (AFNR) careers and life. However, lack of empirical data evaluating student outcomes associated with varied curriculum and CDE connections forces AFNR educators to make preparation decisions without knowledge of the potential impact on student...
Show moreSchool-based agricultural education (SBAE) offers copious opportunities through the classroom and career development events (CDEs), among other contexts, to prepare students with knowledge and skills related to agriculture, food, and natural resources (AFNR) careers and life. However, lack of empirical data evaluating student outcomes associated with varied curriculum and CDE connections forces AFNR educators to make preparation decisions without knowledge of the potential impact on student learning and performance. The current study sought to address the identified problem in a specific Michigan SBAE context by determining the relationship between Michigan AFNR educators' environment and natural resources curriculum and the Michigan FFA Environmental Skills CDE and associated student outcomes. Quantitative survey methodology was utilized to collect and analyze data from the target population, all Michigan AFNR educators during the 2017-2018 school year. Findings identify a small, positive correlation between the Environmental Skills CDE and curriculum spectrum (CDECS) alignment and student outcomes of rank in the CDE and performance on high-order educational objective components. Additionally, AFNR educator characteristics which influence the Environmental Skills CDECS alignment were identified. Findings support Bronfenbrenner's (1979b; 2005) ecological systems theory, the framework for the current study. Recommendations are provided for Michigan AFNR educators, teacher educators, CDE coordinators, and researchers to improve student learning through CDE and curriculum connections.
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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: 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: Evaluation of changes in Sculpin populations in the Great Lakes associated with shifts in benthic species composition
Creator: Volkel, Shea Lynn
Date: 2019
Collection: Electronic Theses & Dissertations
Description: In the Great Lakes, slimy sculpins (Cottus cognatus) and deepwater sculpins (Myoxocephalus thompsonii) were historically abundant native deepwater fishes that served as important prey items for native piscivores (e.g., lake trout, Salvelinus namaycush, and burbot, Lota lota). However, both of these species have been declining in abundance and biomass recent decades according to USGS trawl surveys. The timing of these declines in sculpin biomass and abundance coincides with several ecological...
Show moreIn the Great Lakes, slimy sculpins (Cottus cognatus) and deepwater sculpins (Myoxocephalus thompsonii) were historically abundant native deepwater fishes that served as important prey items for native piscivores (e.g., lake trout, Salvelinus namaycush, and burbot, Lota lota). However, both of these species have been declining in abundance and biomass recent decades according to USGS trawl surveys. The timing of these declines in sculpin biomass and abundance coincides with several ecological disturbances that have occurred throughout the Great Lakes, including the invasions of dreissenid mussels (zebra, Dreissena polymorpha; quagga, D. bugensis) and the aggressive round goby (Neogobius melanostomus), along with the collapse of Diporeia (formerly one of the most important prey items for these sculpin species). In this dissertation, we provide a comprehensive review of the state of knowledge and investigate the effect of these ecological disturbances on slimy and deepwater sculpins in the Great Lakes. We predicted that these ecological disturbances have negatively affected both slimy and deepwater sculpin populations, particularly slimy sculpins, which we could observe through changes in their spatial (depth) distribution patterns (e.g., shifting deeper to avoid round goby) and body condition (e.g., lower body condition associated with ecological disturbance). Our results indicate that slimy sculpins may be more vulnerable to these ecological disturbances than deepwater sculpins, but data limitations prevent us from offering conclusive causal mechanisms for sculpin spatial and body condition patterns. Both our review and analyses implicate that we need to gain a better understanding of sculpins in order to restore these species in this system.
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Title: The Portland cement industry
Creator: Myers, Charles R.
Date: 1926
Collection: Electronic Theses & Dissertations

Title: The relationship of aging on the rate of vocal fatigue based on personal rating scales and fundamental frequency
Creator: Sowa, Olivia Rae
Date: 2018
Collection: Electronic Theses & Dissertations
Description: INTRODUCTION: The relationship between aging and the quality of voice has been researched for the last several decades. Multiple studies have found that females older than 40 consistently experience more instances of voice problems than their male counterparts. RESEARCH QUESTION: to what degree does a vocal loading task fatigue older women? How does the rate of vocal fatigue compare to that found in younger women? METHODS: Eleven female subjects from the age of 55-70 years old were recruited....
Show moreINTRODUCTION: The relationship between aging and the quality of voice has been researched for the last several decades. Multiple studies have found that females older than 40 consistently experience more instances of voice problems than their male counterparts. RESEARCH QUESTION: to what degree does a vocal loading task fatigue older women? How does the rate of vocal fatigue compare to that found in younger women? METHODS: Eleven female subjects from the age of 55-70 years old were recruited. Participants read aloud for 36 minutes at predetermined dB levels in an attempt to induce vocal fatigue. Subjective and acoustic vocal measures were taken not before and after the vocal loading task and at intervals during the task. RESULTS: Subjective results, acoustical parameters, and comparison data from the younger population were found to not be significant. CONCLUSION: The results of the study showed that vocal loading task did vocally fatigue the participants based on subjective ratings. Acoustically there trending evidence of fatigue from the loading task. The aging female population did not vocally fatigue at any greater rate than their younger counterparts. However, there was evidence that fatigue rate did relate to pulmonary health (estimated lung age) in the older population.
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Title: 3-methyl-4-hydroxy diphenylmethane
Creator: Wardwell, Gladys Kidder
Date: 1924
Collection: Electronic Theses & Dissertations

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: Frequency dependent selection and fluorescent nodule phenotyping in the legume/rhizobia symbiosis
Creator: Siler, Eleanor A.
Date: 2018
Collection: Electronic Theses & Dissertations
Description: "The relationship between legumes and rhizobia is an important model mutualism for several reasons. It is essential to agriculture, it provides a crucial ecosystem service by fixing atmospheric nitrogen, and it provides a tractable system for examining questions about mutualism, evolution, and ecology [1, 2]. This symbiosis remains generally mutualistic despite the fact that models predict that mutualistic rhizobia will eventually be out-competed and overwhelmed by parasitic rhizobial...
Show more"The relationship between legumes and rhizobia is an important model mutualism for several reasons. It is essential to agriculture, it provides a crucial ecosystem service by fixing atmospheric nitrogen, and it provides a tractable system for examining questions about mutualism, evolution, and ecology [1, 2]. This symbiosis remains generally mutualistic despite the fact that models predict that mutualistic rhizobia will eventually be out-competed and overwhelmed by parasitic rhizobial symbionts known as cheaters. Here I investigate one possible mechanism that could maintain the diversity of rhizobia strains: frequency-dependent selection. I also introduce a novel method of conducting rhizobia competition experiments that uses non-destructive macroscopic fluorescent imaging to identify rhizobial symbionts in root nodules."--Page ii.
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Title: Urban expansion and urban environmental evaluation in Chengdu, China
Creator: Tao, Shiqi
Date: 2019
Collection: Electronic Theses & Dissertations
Description: 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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Title: The effects of near, medium, and far prior speech context on function word perception
Creator: Streicher, Corinne
Date: 2018
Collection: Electronic Theses & Dissertations
Description: When listening to rapid, casual speech, humans effortlessly perceive boundaries between words that may be only weakly encoded in the acoustic information. Research into the temporal characteristics of speech has demonstrated that when context speech rate is manipulated, the number of words heard by a listener can be altered. Building on this research, this study investigated how specific manipulations of different portions of recorded speech can produce a disappearing word effect in which a...
Show moreWhen listening to rapid, casual speech, humans effortlessly perceive boundaries between words that may be only weakly encoded in the acoustic information. Research into the temporal characteristics of speech has demonstrated that when context speech rate is manipulated, the number of words heard by a listener can be altered. Building on this research, this study investigated how specific manipulations of different portions of recorded speech can produce a disappearing word effect in which a heavily co-articulated function word may be perceived as a part of the preceding syllable, e.g., “John didn’t tell the junior or representative about it.” The stimulus conditions entailed different numbers of syllables expanded/slowed, starting from the beginning of the sentence up through the target portion. Participants (n=34) listened to these sentences and typed what they heard. Results were analyzed for proportion of function words reported. It was found that all slowed conditions resulted in a decreased frequency of hearing function words. A stronger effect was associated with additional expanded syllables. These results suggest that slowing non-adjacent prior context elicits the LRE, a finding that may inform communicative disorders research including dyslexia intervention.
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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: "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: 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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