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Title: SPATIAL AND THERMAL ECOLOGY OF LAKE TROUT (SALVELINUS NAMAYCUSH) IN LAKE ERIE
Creator: Funnell, Tyler R.
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Rehabilitation of lake trout (Salvelinus namaycush), which historically was the coldwater apex predator of much of the Laurentian Great Lakes, is a priority for fishery management agencies in the region. In Lake Erie, the shallowest and southern-most Great Lake, successful rehabilitation of lake trout has been hindered by limited wild recruitment, possibly related to the lake’s warm temperatures and restricted oxythermal habitat. I used acoustic telemetry tracking technology to investigate...
Show moreRehabilitation of lake trout (Salvelinus namaycush), which historically was the coldwater apex predator of much of the Laurentian Great Lakes, is a priority for fishery management agencies in the region. In Lake Erie, the shallowest and southern-most Great Lake, successful rehabilitation of lake trout has been hindered by limited wild recruitment, possibly related to the lake’s warm temperatures and restricted oxythermal habitat. I used acoustic telemetry tracking technology to investigate how lake trout spatial and thermal habitat use varies seasonally in Lake Erie to better understand whether limited recruitment could be caused by thermal conditions in the lake. As expected, lake trout were restricted to the offshore region of the eastern basin of Lake Erie during summer stratification. During fall, lake trout tended to occupy the southern nearshore region of the eastern basin, suggesting the importance of focusing spawning habitat restoration in this part of the lake. Tagged fish dispersed long distances at much higher frequencies than other Great Lakes populations of lake trout. Lake trout in Lake Erie occupied thermal habitat similar to other Great Lakes populations during summer stratification. Following destratification in fall, fish were exposed to warm temperatures, in some years for extended periods. Lake trout hatchery strains of Finger Lakes, NY, origin occupied similar summer temperatures and warm temperatures for more days during fall than Great Lakes origin strains, contrary to findings from Lakes Huron and Ontario. These results reveal behaviors that can inform management of lake trout in Lake Erie and throughout the Great Lakes and could begin to explain recruitment failure observed in Lake Erie.
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Title: Documenting the geomorphic impacts of high lake level on freshwater coastal wetlands using topobathymetric surveys : a case study from Saginaw Bay in Lake Huron
Creator: Castro, Megan Grace
Date: 2022
Collection: Electronic Theses & Dissertations
Description: There has been extensive research connecting vegetative processes in coastal freshwater wetlands and water level fluctuations. However, there is little work on changes to wetland geomorphology, what those transformations may be, and how they impact the wetland. This paper aims to identify changes in wetland geomorphology and decern any correlation between water level and vegetation extents. Data for this study spans from 2012 to 2021, capturing the most recent period of rising water levels....
Show moreThere has been extensive research connecting vegetative processes in coastal freshwater wetlands and water level fluctuations. However, there is little work on changes to wetland geomorphology, what those transformations may be, and how they impact the wetland. This paper aims to identify changes in wetland geomorphology and decern any correlation between water level and vegetation extents. Data for this study spans from 2012 to 2021, capturing the most recent period of rising water levels. Vegetation extent imagery and topobathymetric data were collected during field excursions in the summer of 2021 and compared to NAIP imagery acquired from USGS Earth Explorer and topobathymetric LiDAR data from NOAA Data Access Viewer. Imagery from 2021 was collected using a DJI Phantom 4 Pro quadcopter drone and 2021 topobathymetric data utilized an RTK-GPS antenna and Seafloor Systems SonarMite single-beam echosounder to conduct boating, kayaking, and wading surveys at each study site. Studies took place at Wigwam Bay and Quanicassee State Wildlife Areas located in Saginaw Bay of Lake Huron. Findings show water level had a variable impact on vegetation extent and suggest that erosion of sediment occurred during high water levels at both sites. Results show observable changes in geomorphology adjacent to the wetlands. Changes to geomorphology could potentially impact the size, health, and ecosystem services of coastal wetlands. This initial study has limitations due to the nature of available historical data but is intended as a first step towards further understanding the role of geomorphology in coastal freshwater wetland systems.
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Title: EFFECTS OF PLANT GROWTH REGULATORS AND WEATHER ON BITTER PIT INCIDENCE IN ‘HONEYCRISP’ APPLE
Creator: Griffith, Chayce
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Bitter pit is a physiological disorder of apple linked with Ca deficiency and characterized by dark lesions on the surface of fruit. The commercially important cultivar ‘Honeycrisp’ is highly susceptible to the disorder. In-planta Ca transport occurs exclusively in the xylem; therefore, Ca deficiency in fruit is primarily the result of gradual xylem dysfunction. Because auxin promotes xylogenesis, we hypothesized that early-season applications of both native and synthetic auxins and ABA would...
Show moreBitter pit is a physiological disorder of apple linked with Ca deficiency and characterized by dark lesions on the surface of fruit. The commercially important cultivar ‘Honeycrisp’ is highly susceptible to the disorder. In-planta Ca transport occurs exclusively in the xylem; therefore, Ca deficiency in fruit is primarily the result of gradual xylem dysfunction. Because auxin promotes xylogenesis, we hypothesized that early-season applications of both native and synthetic auxins and ABA would improve xylem longevity and functionality resulting in higher Ca concentrations in fruit and reduced bitter pit. Using several experimental approaches, we demonstrate that auxins and ABA significantly prolong xylem function and markedly reduce bitter pit incidence. A multiple regression model was also developed to correlate temporal climatic data with bitter pit incidence over multiple years and disparate sites throughout Michigan. Collectively, results suggest potential novel uses of plant growth regulators to mitigate bitter pit.
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Title: SOUTHERN CONJURE WOMEN : MANIFESTORS OF SOUTHERN BLACK JOY
Creator: Drake, Keshunta
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Southern Conjure women are the manifestors of Southern Black joy. Southern conjure women are women from or in the South. These women utilize root work and/or conjure as a means of empowerment, self-preservation, and healing. In the discussion of Southern conjure women, I employ "conjure feminism" to understand the significance of Southern conjure women and their role in society. In addition, I also use Lindsey Stewart's The Politics of Black Joy to discuss how root work plays a significant...
Show moreSouthern Conjure women are the manifestors of Southern Black joy. Southern conjure women are women from or in the South. These women utilize root work and/or conjure as a means of empowerment, self-preservation, and healing. In the discussion of Southern conjure women, I employ "conjure feminism" to understand the significance of Southern conjure women and their role in society. In addition, I also use Lindsey Stewart's The Politics of Black Joy to discuss how root work plays a significant role in the production of Southern Black joy. In my discussion of the Southern conjure woman, I explore Gloria Naylor's Mama Day and Ntozake Shange's Sassafrass, Cypress & Indigo. I utilize characters from these works as archetypes of Southern conjure women. I also talk about how each character utilizes root work and conjure to manifest Southern Black joy.
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Title: The Role of the Campus Outdoor Environment on University Student Mental Health : A Study Focusing on the Michigan State University Campus
Creator: Koning, Mallory Marie
Date: 2022
Collection: Electronic Theses & Dissertations
Description: ABSTRACTThe Role of the Campus Outdoor Environment on University Student Mental Health: A Study Focusing on the Michigan State University CampusByMallory Marie Koning The mental health and wellness of university students has been a pressing concern in recent years in the US and is becoming an even larger issue due to the COVID-19 Pandemic. The main purpose of this study is to investigate the correlations between university student mental health and their campus’s outdoor environment. To...
Show moreABSTRACTThe Role of the Campus Outdoor Environment on University Student Mental Health: A Study Focusing on the Michigan State University CampusByMallory Marie Koning The mental health and wellness of university students has been a pressing concern in recent years in the US and is becoming an even larger issue due to the COVID-19 Pandemic. The main purpose of this study is to investigate the correlations between university student mental health and their campus’s outdoor environment. To gather data for this research, an online survey was designed based on literature review and distributed to students at Michigan State University. Students were asked questions about their overall mental well-being, as well as questions about their environmental perceptions, outdoor activity, views to nature through windows and safety concerns regarding their outdoor campus environment. Among 161 survey respondents, the major findings of this study indicate a significant difference in mental health scores for windows in living quarters, where students with living quarter windows had better mental health scores (MHS) than students without living quarter windows. This study also found a marginally significant difference in the MHS for students with classroom windows, where students with classroom windows had better mental health than students without classroom windows. These results also indicated a stronger need for windows in living quarters than on campus. Other results of this study include a significant difference in MHS for students’ perception of safety on campus, outdoor work time, and perception of greenspace on campus. Future landscape designers, university planners, and student counselors will be able to use this study to determine what kinds of outdoor spaces should be created and used to improve the well-being of students.
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Title: PRESCRIPTION OPIOIDS, OPIOID USE DISORDERS, AND OPIOID DEATHS ACROSS 21 OECD NATIONS
Creator: Siddiqui, Zehra Jabeen
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Since the 1990s, the United States has seen increased prescription opioid consumption (POC) and an increase in the prevalence of opioid use disorders (OUD) and the opioid disorder death (ODD) rate. This paper examines three factors that may have fueled the opioid crisis: increased supply of prescription opioids, increased demand for opioids because of pain and economic related despair. A regression analysis of twenty-one OECD nations was used to examine the determinants of and the...
Show moreSince the 1990s, the United States has seen increased prescription opioid consumption (POC) and an increase in the prevalence of opioid use disorders (OUD) and the opioid disorder death (ODD) rate. This paper examines three factors that may have fueled the opioid crisis: increased supply of prescription opioids, increased demand for opioids because of pain and economic related despair. A regression analysis of twenty-one OECD nations was used to examine the determinants of and the relationships between POC, OUDs, and ODDs. Over 1991-2019, consumption did not have a significant effect on OUDs or ODDs, but over 2003-2019 it had a positive significant effect on both. These results held if the US was removed from the sample, supporting some supply side effect across the panels after 2003. Furthermore, OUDs have a large, positive and significant effect on ODDs, indicating two possible pathways direct (straight from consumption) and indirect (through an effect on opioid use disorders) that POC relates to increased ODDs. One model estimates that 39% of the increase in US opioid fatalities is attributable to increased POC between 2003-2010.
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Title: Training Behavior Technicians to Implement Naturalistic Object Imitation Using Behavioral Skills Training
Creator: Walker, Ashley N.
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The purpose of this study was to evaluate the effects of Behavioral Skills Training (BST) on teaching behavior technicians to implement imitation training, in the form of naturalistic behavioral interventions, to a confederate adult. Using a concurrent multiple baseline across participants design, participants were exposed to baseline conditions and given the instruction to teach the adult confederate how to imitate. Then, participants were exposed to a single BST session. Following BST,...
Show moreThe purpose of this study was to evaluate the effects of Behavioral Skills Training (BST) on teaching behavior technicians to implement imitation training, in the form of naturalistic behavioral interventions, to a confederate adult. Using a concurrent multiple baseline across participants design, participants were exposed to baseline conditions and given the instruction to teach the adult confederate how to imitate. Then, participants were exposed to a single BST session. Following BST, participant behavior was monitored further in the presence of the confederate. Results suggest BST resulted in an improvement in imitation training for all three participants. Limitations and future directions are discussed.
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Title: Examination of soilborne pathogens of celery in Michigan
Creator: Peterson, Annika
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Michigan celery field and greenhouse yield and quality is negatively impacted by soilborne pathogens. Celery growers have observed a crown rot, wilt, and vascular discoloration called “meltdown”. Symptomatic celery plants were collected from seven grower commercial grower fields across four counties and two years. Isolations showed the most common organisms observed were Fusarium solani species complex (52%) and Fusarium oxysporum species complex (45%) as identified by sequencing of the...
Show moreMichigan celery field and greenhouse yield and quality is negatively impacted by soilborne pathogens. Celery growers have observed a crown rot, wilt, and vascular discoloration called “meltdown”. Symptomatic celery plants were collected from seven grower commercial grower fields across four counties and two years. Isolations showed the most common organisms observed were Fusarium solani species complex (52%) and Fusarium oxysporum species complex (45%) as identified by sequencing of the translation elongation factor-1α. Isolates identified as Fusarium oxysporum f. sp. apii race 2 (Foa race 2), the cause of Fusarium yellows, using diagnostic primers caused disease in a growth chamber pathogenicity assay. Foa race 2 isolates are capable of causing disease symptoms but are infrequent so “meltdown” may have additional cause(s). Pythium root rot decreases quality of greenhouse grown celery transplants. Pythium spp. isolated from symptomatic celery seedlings were characterized by virulence and fungicides tested for control of Pythium root rot. The most frequent Pythium species collected from Michigan celery were P. mastophorum (55%), P. intermedium (16%), P. sulcatum (10%), P. aff. diclinum (6%), and P. sylvaticum (5%). P. sulcatum and P. sylvaticum caused disease symptoms on celery seedlings in a greenhouse virulence assay. Phosphorous acid salts, ethaboxam, and mefenoxam controlled Pythium root rot in a greenhouse setting. Results indicate which Pythium spp. are of most concern to celery growers and identify effective chemical controls. Understanding presence and virulence of soilborne plant pathogens in Michigan celery production will be used to develop strategies to limit disease.
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Title: THE BACKBONE OF FISHERIES : INDONESIAN WOMEN IN SMALL-SCALE FISHERIES ORGANIZE TO OVERCOME GENDER INEQUALITIES
Creator: Ratri, Annisa Meutia
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Worldwide, women's contributions in the fisheries sector are significant and include fish harvesting, processing, and marketing, among others. However, women often face discrimination and are not recognized in the sector by their male counterparts, managers, and policymakers. This thesis aims to examine the motives for the establishment of women organizations in Indonesia, the Indonesian Fisherwomen's Sisterhood Group (Persaudaraan Perempuan Nelayan Indonesia/PPNI), and to investigate how the...
Show moreWorldwide, women's contributions in the fisheries sector are significant and include fish harvesting, processing, and marketing, among others. However, women often face discrimination and are not recognized in the sector by their male counterparts, managers, and policymakers. This thesis aims to examine the motives for the establishment of women organizations in Indonesia, the Indonesian Fisherwomen's Sisterhood Group (Persaudaraan Perempuan Nelayan Indonesia/PPNI), and to investigate how the lives of women belonging to the organization have changed. This study is based on a qualitative case study using both primary and secondary sources. The primary data consists of interviews conducted via Zoom and phone interviews. This study adopts a Feminist Political Ecology (FPE) framework to examine barriers that women experience that led to the collective action to establish a women-specific fishery organization. Issues related to economic and environmental changes, lacking access to decision-making processes and resources, and lacking recognition were pivotal for women in the sector to organize themselves. This study found that being part of the organization can become a strategy for women in fisheries to overcome barriers in the sector. This study also shows that PPNI allows women in the sector to renegotiate their roles and rights within their households, communities and in the sector. Thus, since the establishment of PPNI, the organization has made efforts to foster gender equality, mainly to support changing women’s lives through women's empowerment.
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Title: INTENSITY IN TEACHING : DEVELOPING AN AFFECTIVE FRAMEWORK FOR WRITING INSTRUCTORS
Creator: Chapman Ball, Cadaxa
Date: 2022
Collection: Electronic Theses & Dissertations
Description: This qualitative research project aims to develop an affective framework for writing pedagogy through analyzing narrative data collected over the course of one semester teaching MSU’s first-year writing course, WRA 101: Writing As Inquiry. The narrative data consists of journal entries and reflections remarking on my own affective states in the writing classroom. Through analyzing these writings, this thesis reveals how and why affect theory has useful applications in writing pedagogy; namely...
Show moreThis qualitative research project aims to develop an affective framework for writing pedagogy through analyzing narrative data collected over the course of one semester teaching MSU’s first-year writing course, WRA 101: Writing As Inquiry. The narrative data consists of journal entries and reflections remarking on my own affective states in the writing classroom. Through analyzing these writings, this thesis reveals how and why affect theory has useful applications in writing pedagogy; namely, that instructors who attend to their own affective responses have the opportunity to better understand the changes they need to make to their teaching practices as well as the systems in which they teach.
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Title: USING SALVAGED LUMBER AS A FEEDSTOCK FOR MANUFACTURING STRUCTURAL GLULAM
Creator: MALI, AMAR BAJIRAO
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Every year tons of old wood end up in landfill landfills as there is no lucrative alternative. A glued-laminated timber section made with salvaged lumber could make an efficient use of the salvaged material and reduce the cost of wood in the market. A 3-point bending test was conducted on a total of 120 specimens to investigate the mechanical properties of glued-laminated timber manufactured using salvaged lumber. Balanced layups were used for this test. The MOE, MOR, and reliability of the...
Show moreEvery year tons of old wood end up in landfill landfills as there is no lucrative alternative. A glued-laminated timber section made with salvaged lumber could make an efficient use of the salvaged material and reduce the cost of wood in the market. A 3-point bending test was conducted on a total of 120 specimens to investigate the mechanical properties of glued-laminated timber manufactured using salvaged lumber. Balanced layups were used for this test. The MOE, MOR, and reliability of the salvaged lumber were assessed according to the experimental results. The influence of the position of salvaged lumber on the MOE and MOR of glulam was investigated by one-way ANOVA. The influence of the type of adhesive used for manufacturing glulam were was also studied. The results show that that when compared with control samples of glulam, the glulam manufactured with 60% of salvaged lumber had a reduction of 10.5% in MOR, 10.5% in MFL, and 1.9% in MOE as shown in table 4.1. when compared with control samples of glulam the glulam manufactured with 40% of salvaged lumber had a reduction of 4.7% in MOR, 4.5% in MFL, and 1.35% in MOE. These reduction percentages are less than 11% for all mechanical properties. In other words, we can say that even for glulam samples made of 60% of salvaged lumber the reduction percentage for all mechanical properties is going to be less than 11%. The reduction percentage for MOE between two consecutive grades turns out to be 33% approximately so we can safely say in absence of any data about a given salvaged sample we can assume that MOE of that salvaged lumber will be one grade below the actual MOE of that sample before use.
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Title: Data-Driven Modeling and Analysis of Residential Building Energy Consumption and Demand Flexibility
Creator: Kawka, Emily
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Buildings are responsible for approximately 74% of total electricity consumption, the leading contributor of carbon dioxide emissions in the United States. As initiatives aim toward net zero emissions through electrification and clean energy, building energy efficiency measures are crucial to achieve this clean energy transition. Through measuring energy use, this increases the accuracy of building use assumptions, which drive how energy use reduction is investigated and targeted. As...
Show moreBuildings are responsible for approximately 74% of total electricity consumption, the leading contributor of carbon dioxide emissions in the United States. As initiatives aim toward net zero emissions through electrification and clean energy, building energy efficiency measures are crucial to achieve this clean energy transition. Through measuring energy use, this increases the accuracy of building use assumptions, which drive how energy use reduction is investigated and targeted. As disruptive events and technology shift how occupants use residential buildings, this has the potential to shift how they consume their energy. In this thesis, high resolution, disaggregated energy use data is used to model and analyze energy use for two specific disruptions: the COVID-19 pandemic and electric vehicles (EVs). The first study measures how COVID-19 impacted residential building energy use. The findings of this research indicate an increase in energy use for both weather-dependent loads and weather-independent loads during the COVID-19 pandemic. Additional analyses give insight to the pandemic’s impact by household income, demonstrating the lowest and highest income groups experiencing larger increases in consumption while remaining populations experienced smaller shifts. The second study analyzes residential EV charging behavior and models the maximum load reduction potential for demand response in the Midcontinent Independent System Operator (MISO) region. The results of this study indicate relatively consistent charging use patterns across a full year, weekend charging is more distributed throughout the daytime compared to weekday charging, and there are significant opportunities to reduce or shift EV loads during typical peak load periods.
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Title: MONITORING AND MODELING ECOHYDROLOGICAL PROCESSES IN VEGETATED WATERSHEDS
Creator: Pham, Leo Triet
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Ecohydrology links ecological and hydrological processes and considers interactions between water resources and ecosystems. Modeling tools are not only important for studying the mechanisms of ecological patterns and processes but also for assessing the effects of environmental change on hydrological and ecological processes, providing insights and solutions to issues in water management. This thesis explores various data-driven approaches to monitor and model these processes at 95 watersheds...
Show moreEcohydrology links ecological and hydrological processes and considers interactions between water resources and ecosystems. Modeling tools are not only important for studying the mechanisms of ecological patterns and processes but also for assessing the effects of environmental change on hydrological and ecological processes, providing insights and solutions to issues in water management. This thesis explores various data-driven approaches to monitor and model these processes at 95 watersheds in western USA using a combination of seasonal and annual climate, hydrometric, and remotely sensed vegetation data. In one analysis, we show that a trend in earlier peak in spring vegetation activity may be a linked to reduced runoff availability during drought years compared to non-drought years. We also provide evidence that increase drought severity is consistent with a decrease in runoff ratio in forested catchments through regression analysis, supporting the hypothesis that the relationship among water-balance components may shift during drought events. In another analysis, we show that the type and amount of vegetation coverage, among other catchment characteristics, can affect the accuracy of data-driven runoff models. These results suggest that a better understanding of the ecohydrologic processes and characteristics is vital to development of effective long-term strategies to improve the resilience of watersheds.
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Title: EXTRACTION, CONCENTRATION, AND DETECTION OF FOODBORNE PATHOGENS USING GLYCAN-COATED MAGNETIC NANOPARTICLES AND A GOLD NANOPARTICLE COLORIMETRIC BIOSENSOR
Creator: Dester, Emma Faith
Date: 2022
Collection: Electronic Theses & Dissertations
Description: In this work, a rapid method for foodborne pathogen extraction and concentration using magnetic nanoparticles (MNPs) was integrated with a gold nanoparticle (GNP) colorimetric DNA biosensor for fast and accessible detection of target bacteria. Experiments for both extraction and detection were conducted first using pure cultures without interfering food matrix components and followed by testing in food matrices commonly associated foodborne outbreaks. Magnetic concentration was tested with...
Show moreIn this work, a rapid method for foodborne pathogen extraction and concentration using magnetic nanoparticles (MNPs) was integrated with a gold nanoparticle (GNP) colorimetric DNA biosensor for fast and accessible detection of target bacteria. Experiments for both extraction and detection were conducted first using pure cultures without interfering food matrix components and followed by testing in food matrices commonly associated foodborne outbreaks. Magnetic concentration was tested with three bacterial species: Listeria spp., Escherichia coli O157, and Staphylococcus aureus. Then, a colorimetric GNP biosensor was developed and tested for E. coli O157. Glycan-coated MNPs are ideal for foodborne pathogen concentration due to their low cost, simple storage conditions, and bacteria binding capabilities. Meanwhile, GNPs visibly change color upon aggregation, which allows for easy use in colorimetric biosensors without the need for expensive analytical equipment. Results from this study indicate concentration of bacteria to up to 60 times its initial concentration in buffer solution and 11 times in select food matrices. In addition, the colorimetric biosensor was capable of differentiating between target and non-target DNA from pure cultures at concentrations as low as 2.5 ng/μL. Finally, the integrated extraction and detection assay was capable of detecting E. coli O157 from contaminated flour. This assay shows immense promise for rapid foodborne pathogen detection, and evidence-based recommendations for continued optimization have also been identified.
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Title: INVESTIGATION OF NEURODEGENERATIVE TAUOPATHIES USING CAENORHABDITIS ELEGANS
Creator: Vonarx, Derek
Date: 2022
Collection: Electronic Theses & Dissertations
Description: ABSTRACT INVESTIGATION OF NEURODEGENERATIVE TAUOPATHIES USING CAENORHABDITIS ELEGANSByDerek Vonarx Neurodegenerative tauopathies are a class of neurodegenerative disease characterized by the accumulation of tau protein into neurofibrillary tangles in the human brain. Alzheimer’s disease (AD) is one such tauopathy. Until recently, the amyloid β hypothesis, suggesting that accumulation of amyloid β, was the leading hypothesis explaining cognitive decline in Alzheimer’s disease patients. However...
Show moreABSTRACT INVESTIGATION OF NEURODEGENERATIVE TAUOPATHIES USING CAENORHABDITIS ELEGANSByDerek Vonarx Neurodegenerative tauopathies are a class of neurodegenerative disease characterized by the accumulation of tau protein into neurofibrillary tangles in the human brain. Alzheimer’s disease (AD) is one such tauopathy. Until recently, the amyloid β hypothesis, suggesting that accumulation of amyloid β, was the leading hypothesis explaining cognitive decline in Alzheimer’s disease patients. However, treatments that reduce amyloid β levels in the brain, such as aducanumab, have shown limited efficacy, and therefore, the role of tauopathy and the potential synergistic relationship of tau and amyloid β requires further study to understand the mechanism of cognitive decline in AD. One of the many difficulties of studying AD is that cognitive symptoms are not observed until late in life. Because of the late onset of symptoms, modelling AD in mammals is expensive and time consuming. To circumvent these issues, a nematode, C. elegans, model was developed because C. elegans have a short lifespan of three weeks, can be genetically modified to express human tau, and are inexpensive to maintain. A genetically modified C. elegans strain (eat-4::GFP; aex-3::tau) expressing both human tau in all neurons and green fluorescent protein in glutamatergic neurons was developed. It was found that the novel strain exhibits neurodegeneration that can be rescued by supplementation with the epoxide hydrolase inhibitor, 12-[[(tricyclo[3.3.1.13,7]dec-1-ylamino)carbonyl]amino]-dodecanoic acid (AUDA), through an unknown mechanism. This novel strain serves as a useful model to study the mechanism of Alzheimer’s disease cognitive decline as C. elegans have a relatively short lifespan that allows for extensive therapeutic and genetic screening.
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Title: INVESTIGATING OLFACTORY IMPRINTING RELATED BEHAVIORS IN JUVENILE LAKE STURGEON (ACIPENSER FULVESCENS) AND THE POTENTIAL ROLE OF STREAM SPECIFIC AMINO ACID PROFILES
Creator: Kimmel, Jacob G.
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Olfactory imprinting is one mechanism thought to guide natal stream homing and facilitate natal site fidelity, an important reproductive strategy that leads to localized adaptations in genetically distinct fish populations. My thesis investigates olfactory imprinting during early ontogeny in lake sturgeon and the potential role of stream specific amino acid profiles as the guiding odors in olfactory imprinting and stream discrimination by lake sturgeon. In Chapter 1, I test the hypothesis...
Show moreOlfactory imprinting is one mechanism thought to guide natal stream homing and facilitate natal site fidelity, an important reproductive strategy that leads to localized adaptations in genetically distinct fish populations. My thesis investigates olfactory imprinting during early ontogeny in lake sturgeon and the potential role of stream specific amino acid profiles as the guiding odors in olfactory imprinting and stream discrimination by lake sturgeon. In Chapter 1, I test the hypothesis that olfactory memory formation occurs in early development and provide behavioral evidence of olfactory imprinting during the free-embryo and exogenous feeding life stages in lake sturgeon. In Chapter 2, I describe the temporal and spatial variability of amino acid profiles in Great Lakes tributaries and discuss the potential utility and limitations for amino acids to function as odorants guiding olfactory imprinting in lake sturgeon in the Great Lakes. In this chapter, I also provide empirical evidence for olfactory memory formation to artificial amino acid profiles during early ontogeny and suggest further studies to see unequivocal evidence on whether lake sturgeon discriminate stream specific amino acid profiles. This thesis supports the use of streamside rearing facilities for exposing lake sturgeon to natal stream odors during early life stages.
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Title: MODELING INDIVIDUAL VARIABILITY IN GROWTH AND ITS IMPORTANCE : AN APPLICATION FOR LAKE TROUT (SALVELINUS NAMAYCUSH) IN LAKE SUPERIOR
Creator: Stebbins, Elizabeth
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Correctly characterizing growth of fish within a population is a crucial component of fish biology and fishery management because, among other things, it informs population dynamics that affect management decisions. Size-at-age is a common metric of fish growth and is often measured at the population level with the assumption that, on average, all fish of a given age are a given size. Over time, several studies have shown that ignoring individual variability in growth can influence population...
Show moreCorrectly characterizing growth of fish within a population is a crucial component of fish biology and fishery management because, among other things, it informs population dynamics that affect management decisions. Size-at-age is a common metric of fish growth and is often measured at the population level with the assumption that, on average, all fish of a given age are a given size. Over time, several studies have shown that ignoring individual variability in growth can influence population parameter estimates and these inaccuracies can be propagated in population models that are used to calculate reference points for management. In the first chapter we develop a hierarchical, mixed-effects statistical growth model that measures individual variability in growth model parameters and partitions it into two sources. We fit this model to length-at-age data of lake trout (Salvelinus namaycush) from six populations in Lake Superior and show that individual-level variability exceeds population-level variability for this system, and persistent error contributes more to variability in length-at-age. In our second chapter, we simulate a population of fish and predict biological reference points, yield-per-recruit, and spawning stock biomass-per-recruit curves from the population using a ‘standard’ method that ignores individual variability and a ‘true’ method that accounts for size-selective mortality and its interaction with individual fish. We show that ignoring individual variability in these models results in overestimation of yield-per-recruit and the biological reference points F0.1 and FMAX. Further, spawning stock biomass-per-recruit is underestimated at low levels of fishing intensity and overestimated at high levels of fishing intensity when individual variability is ignored.
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Title: IS AFRICAN AGRICULTURE EXHIBITING BOSERUPIAN INTENSIFICATION? EVIDENCE FROM RURAL GHANA AND NIGERIA
Creator: Nutsugah, Godwin Kwesi
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The recent increase in the use of capital-using and labor-saving inputs in various parts of Africa has prompted researchers to investigate whether farming systems are innovating consistently with the Boserupian theory of intensification. According to the Boserupian theory, trends in factor price ratios will encourage farmers to substitute more expensive factors with less expensive factors. However, farmer responses to changing factor price trends may be blunted for many reasons, some of which...
Show moreThe recent increase in the use of capital-using and labor-saving inputs in various parts of Africa has prompted researchers to investigate whether farming systems are innovating consistently with the Boserupian theory of intensification. According to the Boserupian theory, trends in factor price ratios will encourage farmers to substitute more expensive factors with less expensive factors. However, farmer responses to changing factor price trends may be blunted for many reasons, some of which could be addressed through public sector action. Using multi-year nationally representative surveys from Ghana and Nigeria, this study therefore broadly investigates the Boserupian hypothesis by analyzing how agricultural households in rural Ghana and Nigeria intensify input use in response to variations in relative input prices. Furthermore, this paper examines whether effects differ by geographic location within a particular nation. The findings from rural Ghana and Nigeria suggest that farmers intensify inputs partly but not entirely consistent with the Boserupian theory. These results indicate that household input use constraints may be systematically different, highlighting the need for regionally appropriate policies or programs that enable households to react more rapidly and entirely to changes in factor price ratios. This study could also provide policymakers, crop scientists, and engineers with insights into the expected trajectory of technical change in the farming systems and guide them in developing appropriate farm technologies and policies.
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Title: LIFE IS NOT JUST BLACK AND WHITE : THE INFLUENCE OF SOCIAL CLASS CUES ON RACE IN AN AFFECT MISATTRIBUTION PROCEDURE
Creator: Carrillo, Alejandro
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Indirect measures of racial bias, such as the Affect Misattribution Procedure, Evaluative Priming Task, and the Implicit Association Task, have been used to provide evidence of stereotypical associations and valenced evaluations towards different racial categories. However, a common limitation shared across these tasks is the tendency to use simplistic racial stimuli that do not capture or account for the multiple categories people may belong to. That is, it is unlikely that people are...
Show moreIndirect measures of racial bias, such as the Affect Misattribution Procedure, Evaluative Priming Task, and the Implicit Association Task, have been used to provide evidence of stereotypical associations and valenced evaluations towards different racial categories. However, a common limitation shared across these tasks is the tendency to use simplistic racial stimuli that do not capture or account for the multiple categories people may belong to. That is, it is unlikely that people are perceived and evaluated along a single feature (i.e., race) but rather at the intersections of multiple categories (i.e., race, age, attractiveness, social class, etc.). Social class, in particular, is a strongly evaluated category and has been shown to share stereotypic associations with race (Moore-Berg & Karpinski, 2019). Thus, this thesis investigated the effects of social class on racial evaluations in an AMP task. Social class was manipulated using occupational clothing in Study 1 and residential areas in Study 2, while race was limited to Black and White men. Across two studies, participants demonstrated a consistent, unexpected pro-Black bias. In addition, an effect of social class was only found in Study 2 such that high-class primes were associated with positive responses. Regarding social class, the results suggest that the manipulations chosen may play an important role in categorization; however, future research is needed to examine just how different class representations impact evaluation.
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Title: A STUDY OF MARGINALIZED NEWS PUBLICATION COMMENTERS AND THEIR MOTIVATIONS AND PERCEPTIONS OF LGBTQIA+ NEWS FORUMS
Creator: Kim, Soojeong
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The majority of news comment studies focus on elite news publications such as The New York Times. These studies typically arrive at one of two conclusions: (a) news comment forums are uncivil spaces and (b) White men dominate the conversation spaces on news websites. Yet we know little about how marginalized news commenters on alternative news publications’ online comment forums perceive news spaces and participate in them. Therefore, 22 commenters active in commenting on marginalized (i.e.,...
Show moreThe majority of news comment studies focus on elite news publications such as The New York Times. These studies typically arrive at one of two conclusions: (a) news comment forums are uncivil spaces and (b) White men dominate the conversation spaces on news websites. Yet we know little about how marginalized news commenters on alternative news publications’ online comment forums perceive news spaces and participate in them. Therefore, 22 commenters active in commenting on marginalized (i.e., LGBTQIA+) publications were interviewed to investigate news commenters’ perceptions and motivations. The Social Identity and Bounded Generalized Reciprocity theoretical frameworks suggest these news comment forums should be perceived as safer and more civil spaces due to their homogenous nature. Social Identity Theory suggests that commenters should behave in a more community-oriented way because of in-group favoritism, while Bounded Generalized suggests individuals’ commenting motivations might be driven by the reciprocal expectation that in-group members will positively reciprocate their comments and support their reputational standing. The interview results rooted in the SIT and BGR theoretical lenses provided support for those commenting motivations: (1) perceived similarity, (2) reciprocity, and (3) reputation acknowledgment, which led them to perceive that interactions are civil and safe on LGBTQIA+ news forums.
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