K-State Electronic Theses, Dissertations, and Reports: 2004 -
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This is the collection for doctoral dissertations and masters theses and reports submitted electronically by K-State students. Electronic submission of doctoral dissertations was required beginning Fall semester 2006. Electronic submission for masters theses and reports was required beginning Fall 2007. The collection also contains some dissertations, theses, and reports from the years 2004 and 2005 that were submitted during a pilot test project. Some items before 2004 have been digitized and are available in K-State Electronic Theses, Dissertations, and Reports: pre-2004. Check the Library catalog for dissertations, theses, and reports not found in these collections.
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Item Open Access Bounding the largest inhomogeneous Diophantine approximation constantPaudel, BishnuFor an irrational real α and real γ ∉ αZ + Z, one defines the two-sided inhomogeneous approximation constant M(α,γ):= liminf_{|n|→∞} |n| ||nα-γ||, and the worst-case of inhomogeneous approximation ρ(α):=sup_{ γ ∉ αZ + Z} M(α,γ). By a well-known theorem of Minkowski, we have ρ(α) ≤ 1/4. This dissertation focuses on bounding ρ(α) in terms of R:=liminf_{i→∞} aᵢ, where aᵢ are the partial quotients in the negative (i.e. the `round-up') continued fraction expansion α. We prove that if R is odd, then the upper bound 1/4 can be replaced by 1/4(1-1/R)(1-1/R²), which is optimal. The optimal upper bound for even R≥ 4 was already known. We also obtain bounds of the form ρ(α)≥ C(R) for any R≥ 3 which are best possible when R is even (and asymptotically precise when R is odd). In particular, ρ(α) ≥ 1/(6√3+8)=1/18.3923..., when R=3, 1/(4√3+2)=1/8.9282…, when R≥4.Item Open Access Effects of oxidative stress, exercise training, and aging in an animal model of autism spectrum disorder.Rogers, LizaBackground: Autism spectrum disorder (ASD) prevalence has increased 175% since 2000 with 1% of the world’s population identified with ASD. Today, ASD affects 1 in 36 children and is characterized by delayed language, motor, and cognitive skills. ASD is characterized by two pillars of pathology: oxidative stress and inflammation. These have been identified as closely related to ASD and many intervention strategies in the literature target these parameters. Purpose: this project will evaluate brain and skeletal muscle oxidative stress via antioxidant expression in a rat model of ASD and the impact of exercise and aging. Methods: Sixteen Long-Evans pregnant rat dams were injected with a single dose of either saline (n=5) or VPA (Sodium Valproate (sigma), 250mg/ml, mixed in saline, 600 mg/kg, n=11). This prenatal exposure to VPA is known to increase the risk of ASD development in offspring. Rats were provided with free access to food and pair-housed with a light cycle of 7 am-7 pm. Rats were enrolled in experiment 1 (exercise study) or experiment 2 (aged ASD study). Experiment 1 animals began a 4-week exercise protocol on the treadmill (Harvard Apparatus, Holliston, MA) on post-natal day 40. Rats ran 5 days a week for 10 minutes at 4.98 m/min, 10 minutes at 7.98 m/min, and 10 minutes at 15.96 m/min for a total of 30 minutes at 0 inclination. Motor coordination was measured with a rotarod both pre and post-intervention. The rod maintained a constant 5rpm speed and the trial ended after 180 seconds. Latency time was recorded for each trial. The littermates of the animals enrolled in the exercise protocol were placed in experiment 2, and aged between 6-18 months to understand the effect of aging on autism. Before the end of life, aged animals performed the Novel Object Recognition task (NOR). Following behavioral testing for both experimental groups, brain and skeletal muscle tissues were collected. Skeletal muscle (soleus, red gastrocnemius) and brain tissue (hippocampi) were homogenized, and western blots were conducted to quantify antioxidant expression. Results: Reduced motor coordination was identified in the experiment 1 VPA groups which was improved with exercise. To confirm an exercise effect, citrate synthase expression was quantified in the soleus muscles. Treadmill-trained animals resulted in higher citrate synthase (CS) activity compared to sedentary animals (p=0.04). Antioxidants superoxide dismutase 1 (SOD1) and catalase were measured in skeletal muscles (experiments 1 & 2), and hippocampi (experiment 2), resulting in declines to antioxidant expression in experiment 1 animals (p<0.05), and declines in aged male antioxidant expression (p<0.05). Conclusion: The protective effect of exercise against ASD pathology is important to understand both in its use as a therapy but also as a tool to highlight the protective pathways.Item Open Access Envisioning Kansas State University as an accredited arboretum with a climate-ready tree collectionOrnelas, DanielClimate change poses a significant threat to the survival and prosperity of trees in Kansas and beyond (Esperon-Rodriguez et al. 2021, Matthews et al. 2018, Mao 2021). As the climate becomes increasingly unpredictable and extreme, numerous tree species will find it challenging to adapt and manage the emerging threats and changing conditions. Anticipated rapid changes in conditions include; drought, shifting hardiness zones, heat zones, increased growing degree days, severe storms, and the emergence of new pests and diseases (Esperon-Rodriguez et al. 2021, Matthews et al. 2018, Primack and Miller-Rushing 2009, Rakow and Lee 2011). Given Kansas's changing climatic conditions and uncertainty about the long-term survival of its existing, regionally adapted trees, there is a pressing need to develop and study an expanded palette of suitable tree species. This project aims to create recommendations for the establishment of an accredited arboretum with a dedicated climate-ready tree collection at Kansas State University (KSU) to disseminate groundbreaking knowledge about trees tailored to Kansas's anticipated end-of-century climatic projections. This study included precedent studies of notable University arboreta were conducted to understand their arboretum components. A survey of subject matter experts from the Kansas Forest Service to understand the current and future challenges, public concerns, and research needs regarding trees in Kansas. A site inventory was performed to understand factors within each of the five K-State campus landscape typologies investigated that could inform the future species selection and placement of new trees within each typology. A climate evaluation examined recent and projected variables related to tree growth and survival across the United States to understand the implications for Kansas by the end of the century and to identify regions that recently exhibit the climatic projections for Kansas. By identifying regions with recent similar climatic conditions, informed decisions were made regarding selecting tree species suited for Kansas’ future. These findings offer insight into what efforts are needed to establish an accredited arboretum with a climate-ready tree collection at Kansas State University. This work provides recommendations that would reinforce KSU's commitment to its land-grant mission by serving as a platform for propagating novel tree information and exemplifying its dedication to education and outreach.Item Embargo Structures and dynamics of the subcontinental lithospheric mantle over the central and eastern North American continent, constrained by numerical modeling based on tomography models.Onyebum, TochukwuDespite being located within a continental plate, the central and eastern United States (CEUS) has been associated active seismicity, often concentrated along seismic zones such as the New Madrid, the East Tennessee, or the South Carolina Seismic Zones. The influence of mantle convection on the CEUS seismicity is still debated. In this study, we investigate the relationship between mantle dynamics and intraplate seismicity. We do this by modeling mantle convection and the induced tectonic regimes and maximal shear stresses, SHmax, from seismic tomography models. Such an approach has already been used by a few authors, but the results seem to be very sensitive to the parameters of the model, particularly the input tomography models, that depict different structures of the mantle and the lithosphere. In this study, we investigate the sensitivity of the model parameters in reproducing the observed seismicity pattern. The uniqueness of our approach is that we use several global (SEMUCB-WM1, TX2019slab, 3D2018_08Sv, and SL2013Sv) and regional (DNA13, CSEM North America, and CURSA2021) tomography models. Using recent conversion laws, R/v, we convert the seismic velocity anomalies provided by tomography models into density anomalies. The density anomalies are then used to compute the instantaneous mantle flow, by considering several rheologies. The modeled convection velocities are used to compute the stress tensor and assess the tectonic regimes and the maximal shear stress, SHmax. Our findings reveal that all the model parameters (i.e., the input tomography models, the conversion factor Rrho/v, and viscosity laws) significantly influence the modeled tectonic regimes and SHmax directions, emphasizing the complexity of the problem. However, the SEMUCB-WM1 and TX2019slab global tomography models, provide a better fit to several observed patterns, such as the compression in the northeastern United States, the extension in the Rio Grande Rift and Basin & Range, and the compression reported in most of the seismic zones. The strike-slip deformation evidenced by earthquake focal mechanism in the central US and extension in the region bound by longitudes 257 and 266 degrees remain unexplained by mantle dynamics alone, warranting further investigation regarding alternative causative factors such as Glacial Isostatic Adjustment and Gravitational Potential Energy. Furthermore, our results show that the regional tomography models generally fail to capture observed tectonic regimes in CEUS, suggesting that the seismicity is created by a larger scale mantle flow than the one occurring beneath CEUS.Item Open Access Transit-Oriented Denver: The impact of transit-oriented development on socioeconomics in Denver County, ColoradoRehm, BenjaminThe aim of my research is to explore if the reconstruction of Denver Union Station had an impact on the socioeconomics in Denver County, Colorado. Additionally, this research seeks to identify what characteristics of gentrification and sustainability are implemented when a new transit infrastructure is introduced to a community. This study specifically adds to the literature in socioeconomics, how to use statistical tools to determine if households have been impacted, and how the community changes. In this report, I examine how the redevelopment of Denver Union Station impacted socioeconomical factors in Denver County, Colorado. To provide a holistic perspective to this exploration, I used a case study and semi-structured interviews with representatives from Denver, Colorado. This site was specifically chosen for its explicit adaptation of Transit-Oriented Development.Item Open Access Functionality and characterization of intermediate wheatgrass in spontaneous fermentation and end product qualityIorga, BriannaIntermediate wheatgrass (IWG) is a perennial wheat and found to have better environmental effects compared to annual plants. Soil nutrition is increased, the plant is drought and disease tolerant, and there is a decrease in labor input. There are also nutritional benefits found in IWG, such as a higher protein, fiber, and mineral content than that of wheat. IWG yield and kernel size is smaller, when compared to wheat though. But the biggest drawback is the decreased amount of high-molecular-weight glutenin subunits (HMW-GS). Throughout various research IWG has been tested in bread products and due to lack in HMW-GS has a poor performance. The Land Institute has been spearheading breeding efforts however and has made improvements to the mixing quality. This study evaluated the breeding efforts and measured the performance of four IWG cultivars in bread making, where one cultivar was specifically bred for mixing quality (MQ). Mixograph parameters and baking trial results were found to be significantly different for MQ. The breeding efforts were found to be successful as dough quality, mixing tolerance, bread volume, and number of cells all increased. The high protein, ash, and starch content indicated IWG would be a suitable candidate in sourdough fermentation. The objective of this study was to determine the performance of IWG in a spontaneous fermentation process, compared to a whole wheat (WW) flour. Three fermentation trials were conducted to determine processing, acidification kinetics, lactic acid bacteria (LAB) and metabolite evolution. IWG was found to have a slightly higher Vmax than WW but achieved higher final TTA. The fermentation quotient (FQ) and lactic acid production were also found to be higher for IWG, in agreement with high LAB enumeration. The sourdough was also utilized in a wheat-based bread trial and were analyzed for specific volume, firmness, acidity, and a first day to visual mold analysis. The IWG bread was found to be more acidic but had no negative effects to the product quality including volume and post-bake firmness. The spontaneously fermented sourdoughs were also evaluated in a sensory analysis. IWG sourdough or whole wheat sourdough was added to a wheat-based formulation and evaluated with a degree of difference (DOD) test and Just About Right scale (JAR) (N= 50 responses in 2 sessions). This was to determine how similar or different IWG was from WW and determine how the breads do or do not meet consumer expectations. Four attributes (appearance, aroma, flavor, and texture) and overall questions were analyzed for both DOD and JAR. An action criteria of 2 was chosen for the DOD, signifying that below 2 there was low risk consumers would notice a difference. IWG had a DOD average of 2.4. However, panelists also found differences in a WW blind control (1.8). This is an indication that panelists were looking for a difference, thus actual difference can be assumed to be smaller. Both IWG and WW had an average JAR score above 3 (“meets expectations”), indicating that despite the differences noticed IWG still met consumer’s expectations. With formula optimization the samples could align more, allowing for the potential use of IWG in a sourdough process and wheat-based bread.Item Open Access We work better together: using an ensemble of natural language processing and forced choice to measure conscientiousnessHeron, XavierThe primary aim of this thesis was to implement a research design which collected forced choice data and text data simultaneously, then examine the psychometric properties of an ensemble model generated from both the forced choice data the text data. Forced choice (FC) and language models offer psychometric advantages, as well as advantages in selection settings when compared to Likert scales – the traditional method of measuring personality traits (Ozer & Benet-Martinez, 2006). The present research provides psychometric evidence of the validity of a multi-method ensemble approach to measuring conscientiousness. Over 45 trials, participants selected one of two statements in a FC block and then provided a short text explanation of their choice. The FC data was scored using the Generalized Thurstonian Unfolding Model (Zhang et al., 2023). The text data was embedded using pre-trained BERT-base-uncased (Devlin et al., 2018) and trained to predict conscientiousness scores generated from the Chernyshenko Conscientiousness Scale (CCS; Chernyshenko, 2002) using ridge regression. FC scores and Natural Language Processing (NLP) scores were ensembled using linear regression to predict scores generated from the CCS. Construct validity was evaluated using a Multi-Trait Multi-Method table comparing the CCS scores, the NLP-derived scores, the forced choice scores, and the ensemble model scores. Incremental validity of the ensemble model above and beyond the other models was evaluated through two hierarchical regressions predicting GPA and subjective well-being. The ensemble model yielded good criterion-related validity and convergent validity, acceptable discriminant validity, but poor reliability – likely due to unstable forced choice estimates. The ensemble model did not demonstrate incremental validity above and beyond the other estimates.Item Open Access Phenotypic plasticity and ecological memory in Andropogon gerardii: responses to simulated grazing pressureMohammadi, ShahlaThis thesis explores the effects of ecological memory on plants responses to subsequent stressors, specifically focusing on the physiological and biochemical responses of Andropogon gerardii (big bluestem) to grazing pressures. By examining the concept of ecological memory, this research highlights how past environmental stressors, such as grazing, influence future plant responses. Utilizing a multifaceted approach that spans predictive modeling, physiological assessments, and biochemical analyses, this study rigorously tests the hypothesis that the legacy effects of grazing, embodied in ecological memory, profoundly impact A. gerardii's physiological fabric and biochemical mechanisms. Structured into three chapters, the thesis first explores the biochemical and physiological foundations of stress responses, investigating the role of flavonoids and phenolic compounds in mediating A. gerardii's response to simulated grazing stress (Chapter 2). It then examines how these biochemical responses underpin post-defoliation growth and biomass allocation, revealing the echoes of ecological memory in plant growth patterns and resource allocation strategies (Chapter 3). Our findings reveal that ecological memory influences A. gerardii's response to simulated grazing, manifesting in nuanced physiological adaptations. Despite initial hypotheses, the interaction between plant memory and clipping treatments showed a complex effect on chlorophyll content and photosynthetic rates, with plants exhibiting a history of grazing demonstrating enhanced photosynthetic performance post-defoliation. Interestingly, the study underscores the significant role of flavonoids in mediating physiological responses to stress, independent of ecological memory. These secondary metabolites were pivotal in optimizing photosynthetic efficiency and gas exchange, contributing to the plant's defensive responses and recovery post-clipping. Furthermore, the research delves into biomass allocation strategies in response to defoliation, revealing that early-season biomass removal does not significantly affect end-of-season growth traits across plants with and without grazing memory. However, a notable finding was the consistent influence of relative growth rates (RGR) during early and late growth stages on end-of-season biomass, underscoring the inherent growth dynamics as a critical determinant of plant vigor. Contrary to the anticipated benefits of grazing memory on growth enhancement, the study suggests that A. gerardii's immediate physiological responses to defoliation play a more pivotal role than previously hypothesized. While grazing memory appears to confer some degree of adaptive advantage, it does not significantly modulate the correlation between RGR and end-of-season biomass attributes, indicating that innate growth responses are paramount. In conclusion, this thesis illuminates the complexity of ecological memory and its impact on the physiological and growth responses of A. gerardii to grazing. The findings highlight the crucial role of secondary metabolites, particularly flavonoids, in mediating plant responses to stress and suggest that managing the timing and intensity of defoliation may be more effective than leveraging ecological memory in grassland management practices.Item Open Access Optimization of residual herbicide applicationsMeyeres, TylerOptimization of residual herbicide applications is critical to control of herbicide-resistant Palmer amaranth (Amaranthus palmeri S. Watson) and waterhemp (Amaranthus tuberculatus [Moq.] Sauer). In this dissertation, one greenhouse study and three field studies were established to optimize residual herbicide applications. The objective of greenhouse trial was to evaluate the response of multiple-resistant Palmer amaranth to combinations of PS II- and HPPD-inhibitor herbicides. The first field experiment was established to quantify the effect of application timing and spray volume on residual herbicide efficacy in corn. The second field experiment was established to compare Palmer amaranth control with residual herbicides applied preemergence (PRE) or postemergence (POST) in Enlist (2,4-D-resistant) and XtendFlex (dicamba-resistant) cotton systems in Kansas. The final field trial was established to compare the impact of environmental conditions on the efficacy of VLCFA-inhibiting herbicides when applied at various times throughout the growing season. In the greenhouse trial, PRE applications of metribuzin alone, metribuzin combinations, and atrazine + mesotrione resulted in 61 to 87 % control of a Palmer amaranth population resistant to TIR1-, EPSPS-, HPPD-, ALS-, PS II-, and PPO-inhibiting herbicides. POST treatments of atrazine alone and combinations with metribuzin resulted in 40 to 60% control of the same Palmer amaranth population. These results indicate herbicide combinations can be useful to manage multiple-resistant Palmer amaranth, even if resistance to those herbicides has been confirmed. In the corn trial, Resicore (clopyralid + acetochlor + mesotroine) and TriVolt (isoxaflutole + thiencarbazone-methyl + flufenacet) were applied at 56, 122, and 187 L ha-1 in PRE-only or PRE followed by (fb) POST systems in 2021 (Colby and Ottawa, KS) and 2022 (Manhattan, Ottawa, and Scandia, KS). Palmer amaranth control was 94% or greater in Colby throughout the growing season. Resicore provided greater Amaranthus control than TriVolt in no-till systems. Amaranthus control was greater in PRE fb POST systems as compared to PRE-only systems. Spray volume did not effect weed control apart from waterhemp control in Ottawa 2021, where Resicore applied at 56 L ha-1 provided less control than TriVolt applied at 56 L ha-1 and Resicore applied at 187 L ha-1. Data suggests that improper herbicide selection may be of greater consequence than spray volume for residual weed control. Applications in the cotton trial included PRE fb early POST (EPOST) fb late POST (LPOST) in 2021 and PRE fb EPOST in 2022. In 2021, pendimethalin was applied as a blanket PRE. The EPOST application in 2021 included acetochlor, dimethenamid-P, or S-metolachlor + 2,4-D or dicamba or the trait premix, which was glyphosate + 2,4-D or dicamba + S-metolachlor, applied alone. In 2021, the LPOST included glyphosate + 2,4-D or dicamba. In 2021, the LPOST included glyphosate + trait herbicide. In 2022, PRE herbicides were fluometuron or fluometuron + acetochlor, dimethenamid-P, S-metolachlor, or pendimethalin fb EPOST including glyphosate + trait herbicide or in combination with residual herbicides. In 2021, there were no differences in end of season Palmer amaranth control (48 to 71%) observed among residual herbicides as long as more than one herbicide application was utilized. In 2022, Enlist systems provided less control than XtendFlex systems. The greatest control was observed when two applications of residual herbicides were utilized as compared to no over lapping residual apart from two applications of pendimethalin. Results indicate cotton herbicide trait system influences Palmer amaranth control; but, residual herbicide selection, multiple applications, and layered residual herbicides may be of greater importance. To fulfill the objective of the final field trial, a bare-ground field experiment was established in Manhattan, KS in 2021 and 2022 where acetochlor, dimethenamid-P, pyroxasulfone, and S-metolachlor were applied at various dates throughout the growing season to capture variations in rainfall and temperature. The effects of rainfall and accumulated soil growing degree days (SGDD) on the probability of successful weed control were tested by subjecting binary responses (greater or less than 80%) of each herbicide to logistic regression. Excessive rainfall and/or elevated temperatures decreased the probability of successful control of Palmer amaranth with acetochlor, dimethenamid-P, pyroxasulfone, and S-metolachlor, but pyroxasulfone and S-metolachlor may have an advantage at high temperatures and high rainfall. In a scenario, where the rainfall forecast is predicting little rainfall within 3 WAT, pyroxasulfone and S-metolachlor may not be the most effective options. However, acetochlor may be the best fit for hot and dry conditions, as less accumulated rainfall was required to achieve high probability of successful weed control. Dimethenamid-P had a disadvantage in hot and dry conditions but was more likely to have >80% control in cool and wet conditions, indicating dimethenamid-P may be a better fit at plating or prior to planting of corn and soybeans when conditions are cooler.Item Open Access Three essays on the effects of oil prices on imports and exports to ChinaLiu, JiazhenThis dissertation consists of three essays: In the first study, I investigate the macroeconomic response of Asian crude oil importers to oil supply news shocks based on OPEC public announcements using a Structural VAR framework. I look into the macro aspects of the seven largest crude oil importers in Asia through exchange rate channels. My empirical results on the economic aspects indicate that Asian oil importers’ economies receive effect from oil supply news shocks, especially aggregated exports and aggregated imports. My analysis suggests that the effective exchange rate can be an additional channel through which oil news shocks affect the Asian economies indirectly. In terms of the second study, I investigate the export prices for primary agricultural commodities in responses to oil supply news shocks based on the OPEC public announcements. The research is carried out using a Structural VAR instrumented variable framework. I look into the primary agricultural commodities sold from ASEAN members to China, including rubber, palm oil and rice. My empirical results indicate that export prices for primary agricultural commodities in ASEAN receive in but short-run effects from oil supply news shocks. My findings also suggest that the shipping costs between ASEAN and China may be a key channel for the information transmitted from the oil supply news shocks to the ASEAN agricultural commodities prices. The third essay looks into the Chinese non-ferrous metal imports in response to the oil supply news shocks based on the OPEC public announcements as well as the Chinese trade policy uncertainty. The research on oil supply news is carried out using a Structural VAR instrumented variable framework while the trade policy uncertainty is investigated with TVPVAR model. In this paper, I look into the primary non-ferrous metals imported by China, including copper, nickel, aluminum, lead, zinc and tin. My empirical results indicate that the values and spot prices of Chinese non-ferrous metal imports receive little effects from the oil supply news shocks due to contract settlement method. My findings also suggest that an increasing of the Chinese trade policy uncertainty leads to diverse responses of the non-ferrous metal import values but negative responses for the non-ferrous metal import prices.Item Open Access Bridging the Gap Between Intention and Execution: Effective Tree Planting Practices in Manhattan, KansasSaunders, GabrielleTrees provide ecological, social, health, and economic benefits in urban and suburban environments. These include stormwater management, improved perception of safety, shade, and carbon sequestration. The realization of these benefits is contingent on trees growing to their full maturity and the overall wellness of trees. Tree planting ordinances in urban design often call for a certain number of trees for each new development, but design practices and the maintenance needed to keep trees alive often fall short. Young, vulnerable trees planted in harsh environments may only survive a few years past planting, while large, established trees are removed from sites to make way for future development. As trees die due to their surrounding conditions, projected benefits—why they were required and planted—are foregone completely and cities fall short in reaching climate action goals and creating healthy living environments. Insufficient attention is being paid to the implementation and maintenance strategies needed to keep the trees alive and thriving — past the establishment period — in order to actualize their benefits. This study aims to identify those strategies, and how to implement them effectively as high-density residential zoning districts densify from single-family homes to multi-family complexes. Several methods were used to answer the following question: As two sites in Manhattan, Kansas are densified, how can street trees be implemented and maintained to maximize their longevity and receive the full benefits they can provide, based on their contextual and biophysical conditions? Three precedent study reviews are followed by an analysis of residential blocks that have experienced densification and significant tree loss in the last 10 years. Projective designs show how innovative planting strategies can be applied to two sites. Planting design guidelines for future development, including site design essentials, tree planting drawings, and required implementation and maintenance strategies, will help ensure tree health past the establishment period. Design guidelines applied to two sites in Manhattan, Kansas (which have yet to be densified, but have a potential to be based on their zoning classification and contextual patterns of the neighborhoods they belong to) will help the City of Manhattan and Kansas Foresters as they review development proposals. This study builds upon past research and practices to identify when specific planting design, implementation, and maintenance strategies must be applied, and provides a framework that can be used in Manhattan, Kansas and other densifying urban landscapes.Item Open Access Connecting postsecondary quality of life to promises of IDEA: An issue of educational equityHeiman, MargaretThis mixed methods study on postsecondary outcomes for individuals with disabilities focused on the experiences of young adults with intellectual and developmental disabilities (IDD) and significant disabilities from their perspective. The research questions include understanding their overall quality of life (QOL), the supports, services, and experiences they received during Individuals with Disabilities Education Act (IDEA) Part B, and how these experiences contributed to their current QOL as young adults. The study used a constructivist and pragmatic worldview, focusing on the importance of understanding IDEA supports and services from the perspective of individuals who received them. The research design involved collecting both qualitative and quantitative data, with the qualitative phase informed by the quantitative phase. The research was completed in two phases, with the first phase focusing on the participants' overall QOL rating using the Wisconsin Quality of Life Survey and the second phase on the qualitative aspects of their QOL. The research provides a more comprehensive understanding of the experiences and perspectives of young adults with disabilities in postsecondary education. Ultimately, the study participants emphasized the challenges they face as young adults transitioning from IDEA Part B to adulthood. They stressed the importance of social networks and the need for individualized education plan (IEP) teams to support social nuance and meaningful connections throughout all their IDEA journey. The findings also bring to light the need for specialized ages 18-21 special education services, which are crucial for cultivating employability skills and life competencies. The findings in this study highlight the need for bridging the gap between policy and practice, which would empower young adults with disabilities to chart their own destinies with autonomy and agency. By bridging this gap, we can better create a future where individuals with disabilities are not just survivors but architects of their destinies, with dignity, in a place where opportunities abound.Item Open Access Human-environment interactions in rural and agricultural communities: Identifying opportunities for sustainability efforts using quantitative, qualitative, and GIS methodsAmariah, FischerThe United States agriculture industry, especially in the Midwest, is expected to be adversely impacted by the consequences of climate change, with temperature and precipitation changes making sufficient crop production exceedingly difficult to achieve. Further, the agriculture industry is also a significant contributor to climate change and faces a rising global population with increased food demands. The combination of these circumstances creates a context in which members of agriculture and food systems must adapt to a changing climate to increase food production while simultaneously rethinking traditional approaches to agriculture to mitigate contributions to climate change. This makes the study of agricultural sustainability, and the sustainability of the many rural communities that rely on agriculture, essential for the future of our planet. However, given the complex nature of problems in agricultural and rural sustainability, solutions often require an interdisciplinary approach and the consideration and integration of both human and natural systems. The goal of this research was to contribute to agriculture and rural sustainability by conducting three different research projects that each focused on an area of agricultural or rural sustainability. In chapter three, we investigate how the physical water environment shapes water conservation norms among farmers in the High Plains-Ogallala Aquifer, the largest source of groundwater in the United States. These questions were approached in terms of cultural adaptation to the physical environment, comparing irrigators with dryland farmers using survey and environmental data. I used the values-beliefs-norms (VBN) framework to develop a conceptual model to integrate the physical water context as an exogenous explanation of water conservation norms. Grouped simultaneous equation models indicate a limited form of cultural adaptation in the region that, from a biological perspective, could be considered evidence of mal-adaptation. Both irrigators and dryland operators in more water-rich environments hold stronger water conservation norms and those in more arid environments hold weaker water conservation norms. For irrigators, the relationship between the water context and norms is partially mediated by worldviews where irrigators in more water scarce contexts tend to hold more ecocentric worldviews that motivate conservation. The findings suggest the importance of considering farmers’ practices (dryland farming or irrigation) and their places (physical water context) in shaping their decision-making in an integrated socio-ecological context. In chapter four, measures of rurality were investigated. Government agencies and researchers often rely on quantitative measures to map where rural places are and who belongs to rural communities. To better understand the consistency, or lack thereof, across different quantitative rural measures, we compare four common measures applied at the county level for the contiguous United States. My purpose was to (1) quantify and map the degree of rural agreement among these selected rural measures and (2) describe key characteristics of counties classified as rural through urban. Comparing different measures yielded little agreement on rural places with consensus achieved for only 114 of 3,108 counties (3.7%). County variables contributing to good separability in rural to urban classifications included remoteness, population density, percent of the population aged 65 and over, employment in the agricultural sector, and both developed and grassland landcover. Closer examination of the underlying characteristics of the 114 consensus rural counties provides an opportunity to reflect on the nature of popular rural measures and the variables they use. If these counties are not representative of how researchers conceptualize “rural” across US regions, it is motivation for working toward new and/or spatially adaptive rural measures that better represent the communities that policy and research intends to help. In chapter five, the process of regenerative agriculture adoption was examined. To address the negative environmental impact of industrial agricultural practices, research has been dedicated to the adoption of regenerative agriculture (RA) as it has been shown to reduce agriculture’s overall contribution to climate change and better prepare farming operations for future changes in climate. The adoption of RA practices has been linked to systems thinking, with farmers employing regenerative farming practices reporting higher engagement with systems thinking. This study interrogates this relationship further by examining how industrial and regenerative farmers demonstrate systems thinking skills. To do this, sixteen cognitive maps of individual farm systems were collected through qualitative interviews with farmers in central Kansas. These cognitive maps were then used to compare systems thinking skills across farmers employing practices along the spectrum of industrial to regenerative. Results showed that regenerative farmers demonstrated more developed systems thinking skills when compared to industrial farmers. Further, the cognitive maps of regenerative farmers prioritized internal and ecological farm factors, particularly soil health, while those of industrial farmers emphasized external and human-driven farm factors.Item Open Access Extrusion-based 3D Freeze Printing of Multi-functional AerogelsYang, GuangAerogels constitute a unique class of synthetic porous ultralight materials, derived from gels where the liquid component is substituted by gas while retaining the gel structure. Their outstanding material properties, including high porosity and low density, have spurred exploration across various domains such as catalysis, thermal insulation, solar energy utilization, piezoelectricity, energy storage, low-temperature glass formation, sensors, adsorption, and photocatalysis. The integration of 3D printing technology into aerogel production offers unprecedented design flexibility and the capacity to customize material characteristics. Nevertheless, prevailing 3D printing methods for aerogels encounter challenges concerning printability, microstructure regulation, and macrostructure manipulation. To tackle these obstacles, a novel 3D printing method known as 3D Freeze Printing (3DFP) has been developed internally, merging freeze casting with additive manufacturing techniques. This approach facilitates the precise fabrication of tailored geometries with controlled microporous structures. Previous investigations have primarily focused on a limited range of materials such as graphene and silver nanowires, necessitating exploration into diverse materials to unlock the full potential of 3DFP. Additionally, comparative evaluations between multifunctional aerogels produced via 3DFP and those from conventional methods remain unexplored. Former studies predominantly relied on optical imaging for 3DFP characterization, constraining insights into material deposition and solidification. Systematic analysis of the extrusion process and quantitative assessment pose considerable challenges but are crucial for optimizing 3DFP processes across industries like chemical, machinery, electronics, aerospace, and biomedical engineering. This thesis addresses these gaps by fundamentally studying the extrusion-based 3DFP method and its potential applications. After a comprehensive review of freeze casting and current extrusion-based 3D printing techniques, precedes investigations using X-ray synchrotron micro-radiography from leading facilities like the Advanced Photon Source and SLAC National Accelerator Laboratory are presented. These experiments provide real-time insights into material behavior during freeze casting and 3DFP processes. Moreover, the fabrication and characterization of novel cellulose nanocrystal (CNC) aerogels using 3DFP demonstrate exceptional acoustic absorption and mechanical properties tailored through freezing direction modification. These nano-cellulose aerogels present promising applications in ultra-lightweight sound absorption devices for aerospace use. Additionally, this thesis extends to extrusion-based 3D printing of zirconium carbide (ZrC) nuclear fuel cell structures, reporting the influence of additives like Nano Crystalline Cellulose (NCC) and Vanadium Carbide (VC) through rheological and mechanical testing. Integrating additive manufacturing with advanced materials like ZrC and tailored additives marks a significant stride towards sustainable propulsion systems for future space missions. In conclusion, this thesis delves into the fundamental aspects and practical applications of extrusion-based 3DFP, paving the way for optimized aerogel production across diverse industries and advancing materials science for futuristic technologies.Item Open Access Foundational Sorghum Kombucha Research in Swine: Preference, Cognition, and Social TestingNelson, CatherineThe use of swine has the potential to extend greatly beyond their current facets of utilization. The combined advancements in the methodology of behavioral collection and precision animal technology allow for the refinement of swine testing procedures regarding both efficiency and welfare. This thesis will introduce the development of procedures using a novel 3-pod maze to assess preference as well as the social impacts of an in-pen cognitive feeding test. Study 1 was conducted to measure pig preference for three different strains of fermented sorghum tea utilizing a three-pod radial maze. The first phase served to eliminate neophobia by acclimating in pairs with each bowl containing a control isocaloric solution of sugar water (positive control). The second phase conditioned the pigs individually using the positive control in one arm and distilled water (negative control) in the other two arms. The first experimental phase consisted of testing of testing the preference of three different versions of fermented sorghum tea. Each solution utilized a different strain of commercial sorghum: 1) Raw white, mild flavor profile, 2) Raw sumac, medium flavor profile, and 3) Roasted sumac, bold flavor profile. There was no clear preference between strain so in the second experimental phase the three teas were mixed and put into one pod on a rotation with the positive and negative control. Results showed that the 3Tea was the most desirable treatment as it had the highest consumption volume over the positive and negative controls. Total duration spent in the pod as well as duration of head over bowl behaviors was greatest for pods containing the 3Tea mixture and lowest for the negative control. In conclusion, the pigs preferred the 3Tea mixture over a sweetened water. This study provides evidence that pigs do not have a strong aversion to novel, sour, and bitter flavors as previously thought. Study 2 was conducted to test a prototype for an in-pen cognitive feeding task. Pigs were exposed to a cognition task that required them to push a series of paddles to receive a food reward. After a conditioning phase the pigs were randomly assigned a pattern for individual acquisition. The pattern consisted of either alternating, inner or outer paddles. Once the pigs completed the individual acquisition phase they were exposed to the test with the same pattern in pairs. Performance on the task was assessed through latency, duration, and frequency measures. The paired phases allowed for the analysis of social hierarchy and cooperation on task performance with an end goal of assessing if sociality and format impacted test performance. Social behaviors assessed included advance, retreat, and neutral. Frequency data for these social behaviors was utilized to calculate dominance indices and determine social status. Format did not have a significant impact on overall performance. However, the outside format had the highest rate of correct paddle contact leading to the extrapolation that it was the easiest for the pigs to uptake. Submissive pigs also had a significantly higher number of overall paddle presses as well as presses on the correct paddle, indication higher motivation and contrafreeloading status when faced with a cognitive task. Dominant pigs were likened to freeloaders as their higher social status was their main tool for meal acquisition. The results of these studies are assessed together through hematology results reported in the final chapter. Blood was collected from all pigs pre and post study. Dominant and submissive status assigned in study 2 was used to assess hematological differences between pen-mates and the potential health benefits of the fermented sorghum tea consumption. Dominant pigs showed higher levels of plasma glucose, triglycerides, and cholesterol. Dominant pigs also had higher overall body weight correlating with higher fat and inflammatory markers seen in the blood results. Despite an increase in size dominant pigs experienced a decrease in all of these variables post-study, rendering further investigation of the effects of fermented sorghum essential. The development of procedures for these studies will assist in the refinement and ultimate advancement of the role swine can play within the scientific community. A refinement of behavioral and cognitive data collection will create for more efficient and ethical housing of swine in production and translational studies. The methodology outlined within this thesis can be used as a guide for future studies assessing swine preference, cognition, and social hierarchy.Item Open Access Effects of U.S. inflation rates on Fruitful Rim beef cow-calf production input costsBrauman, CallieThe United States relies on the beef industry for both import and export beef; however, the overall U.S. cattle herd size is the lowest it has been since 1954 due to wide variety of factors discussed in this analysis. The United States is one of the top beef exporters in the world, providing beef to many countries. This is also a crucial area of income for the U.S. Due to the increased cost of production and lower profit margins, there have been many herd liquidations across the country, having a negative impact on the national herd size. There are many factors that have affected beef cattle production's overall profitability within the last several years, including but not limited to weather, lack of succession planning, age of cattle producers, global events, and consumer habits. With an increasing inflation rate, many producers are unable to continue beef cattle production due to their inability to financially afford the resources and supplies needed to produce beef cattle, while also providing for their families and covering the increased cost of living. Aside from these things, many cattle producers, as well as other agricultural producers have always been able to rely on lenders to provide capital, allowing them to cover their operating costs until they receive payment for their product. It is the goal of this study to provide insight through analysis determining the effects of United States inflation on cow-calf production input costs within the Fruitful Rim region. This study uses data analysis through both correlation and regression methods. This analysis focuses on data pertaining to cow-calf producers within the Fruitful Rim Region, collected annually by the U.S. Department of Agriculture and the National Agriculture Statistics Services. The data included numerous categories of input costs as well as the Consumer Price Index (CPI) from 1996 to 2022 to analyze the correlation between the input costs and in inflation rates. Through this analysis it was discovered that certain input costs are more affected by changes in inflation than others. For example, there was little to no correlation between the CPI and vet/medicine costs; however, purchased feed cost was directly correlated with the CPI. Purchased feed costs increased $0.55 per head with one unit of increase in the CPI. Cattle for backgrounding were inversely related to the CPI and showed a $0.46 decrease per head of cattle when there was one unit of increase in the CPI. Producers can focus on more affected areas and be less concerned about costs that may not change much. For example, there is no direct correlation between veterinary and medicine costs and the CPI. Therefore, when inflation is increasing this would not be a cost to be as concerned with; however, the results show that purchased feed costs increase with CPI increases. Producers can focus on alternative means of feed, such as grazed feed, to save input costs when inflation is increasing. The information discovered and summarized in this study provides guidance to producers interested in making educated decisions in different economic situations. As the data shows, there are some categories of input costs that are highly affected by changes in inflation; however, there are others that are not affected at all.Item Open Access The effects of transportation on wheat prices to local Kansas wheat farmersShayna, DeGrootWheat farmers in Kansas play a critical role in helping feed the world. They work under volatile conditions that are unpredictable each year such as weather, basis, prices and yield. There are many factors that play into the volatility, specifically for basis prices, like transportation. This can be affected by the price of diesel, rail, ocean freight and futures price. While diesel is a major transportation input on farm operations and in grain transport, costs such as ocean freight and rail for exported commodities can be overlooked. Ocean freight plays a factor as roughly 50% of the wheat grown in Kansas is exported. The goal of this thesis is to examine how prices of diesel, rail, ocean freight and futures affect wheat basis for local wheat farmers across Kansas. The data for this study were collected from AgManager.info, the United States Department of Agriculture Agricultural Marketing Service, the United States Energy Information Administration and the Federal Reserve Economic Data. Data were collected as monthly averages from 2015 to 2023, a nine-year span, which included diesel prices, rail tariff rates, ocean freight rates, wheat futures prices and basis from elevators across Kansas including 21 towns from three counties in each of the seven agriculture districts. Elasticity has some variability across the models. Combining all seven districts, results indicated that on average, a 1% increase in futures would result in a 0.47% decrease in basis, a 1% increase in ocean freight would result in 2.47% increase in basis, a 1% increase in diesel would result in a 0.89% decrease in basis and a 1% increase in rail would result in a 0.12% increase in basis. Farmers should look at futures price, ocean freight, local diesel price and rail tariff rate before making decisions at elevators as all four factors affect wheat basis, with futures and diesel commonly decreasing basis and ocean freight and rail tariff rates commonly increasing basis. By looking at these factors, it will help farmers determine whether to sell their wheat or wait.Item Open Access Effects of flow training on movement, survival, and habitat associations of age-1 Colorado pikeminnow stocked in the San Juan River, Utah, and New MexicoCleveland, JohnStocking of hatchery-reared fish is an increasingly important management action to conserve and restore native fish populations. Colorado pikeminnow (Ptychocheilus lucius) was historically abundant throughout the Colorado River basin until the construction of dams and introduction of nonnative species caused a rapid decline and federal listing as endangered in 1973. Following the presumed extirpation of pikeminnow in the San Juan River in the late 1990s, a stocking program was developed in 2003. Due to an increasing adult abundance and potential for spawning, stocking protocols were changed from stocking young of year to age-1 pikeminnow with passive integrated transponders (PIT) tags to distinguish wild spawned and hatchery reared individuals. The addition of unique tags also allowed for hatchery experimentation such as flow training which was implemented in 2022 and 2023 to increase the survival of stocked age-1 pikeminnow. I used radio telemetry to compare movement, survival, and habitat associations among flow-trained and different size classes of non-flow-trained pikeminnow. We also used PIT tags implanted in stocked pikeminnow to evaluate differences in detection rates across treatments. The mean rate of movement for radio-tagged pikeminnow was similar across treatments (-0.08 ± 0.48 km/hr). At the conclusion of 60 days, no control (0%), one flow-trained (3.3%) and 12 larger pikeminnow (34.3%) were detected and determined to be alive and within our study reach across both years. One individual from the radio-tagged flow-trained group was detected 255 river kilometers downstream approximately five days post stocking in 2022 (rate of -2.13 km/hr), demonstrating the ability to move long distances following stocking. Effects of terrestrial predation was observed in both years with 11 radio transmitters and 59 PIT tags found on dry land within the river corridor. Another radio transmitter was triangulated in a great blue heron (Ardea herodias). Overall, results suggest stocked pikeminnow dispersed quickly downstream; flow-trained pikeminnow prior to stocking did not increase retention of radio tagged individuals; and terrestrial predators may be a large source of mortality. Increasing the duration or velocities of flow training, prey training, or using alternative stocking sites may reduce losses due to predators and emigration.Item Open Access Communicating climate-change impacts to youth: A social influence theory perspectiveCannon, LaurenClimate change is known to have severe impacts on Earth’s temperature, organisms, human health, and habitats. Despite overwhelming scientific evidence, many individuals hold misbeliefs about climate change. Misbeliefs can prevent policy changes or environmental action to reduce climate-change impacts from taking place. Previous scholars have addressed the potential causes behind these misbeliefs, including misinformation, confirmation bias, and tribalism. Since current solutions have not yet significantly reduced these misbeliefs or their causes, this report explores the issue using a social influence theory perspective. By synthesizing literature on social influence theory, climate-change communication, and the use of youth groups and activities for education, it is concluded that communicating to youth groups and their leaders about climate-change impacts could produce the greatest change in reducing misbeliefs. This is due to the combination of normative social influence, leadership and mentorship influence, and healthy environments in youth group structures. These findings inform a communication plan for reducing misbeliefs about climate in youth groups in low socioeconomic areas of Kansas. By educating youth about climate change, we can significantly reduce misbeliefs overall through generational replacement and allow more policy changes and environmental actions to be implemented to reduce climate-change impacts.Item Open Access Use of artificial intelligence to locate and treat weeds in Midwestern United States corn (Zea mays) and soybean (Glycine max) cropping systemsBarnhart, IsaacSite-specific weed management (SSWM) is defined as the process of managing weeds where they are growing as opposed to treating the whole field and treating areas with no weeds. Artificial intelligence (AI), the process of creating intelligent machines, has become a part of everyday life in modern society. Utilizing convolutional neural networks and object detection algorithms, weeds can be distinguished from crops, and herbicide applications can target weeds where they are growing. The objectives of this dissertation were to 1) train open-sourced object detection algorithms to detect in central Kansas soybean (Glycine Max [L.] Merr.) fields, focusing on Palmer amaranth (Amaranthus palmeri S. Watson, henceforth denoted as A. palmeri), 2) determine herbicide efficacy and cost savings of SSWM herbicide applications using a ONE SMART SPRAY research sprayer, an intelligent dual-boom sprayer using AI technology to locate and spray weeds growing within crops, and 3) compare traditional broadcast (BCST) applications with spot-spray (SS) herbicide applications using a commercial-sized ONE SMART SPRAY sprayer. Images were obtained from two soybean fields in 2021 containing A. palmeri infestations and were annotated with bounding boxes to identify both A. palmeri and soybean plants. In this study, the YOLOv5 object detection algorithm was identified as having the highest mean average precision scores and was therefore selected for further analysis. The precision, recall, and F1 evaluation metrics found for the test image dataset was 0.71, 0.70, and 0.71, respectively. Regression analysis revealed that our trained YOLOv5 model evaluation metrics were higher when identifying A. palmeri plants 2 cm in height at low plants m-2. For the second objective, corn (Zea mays L) and soybean field trials were conducted in Manhattan, KS and Seymour, IL with the research-sized ONE SMART SPRAY. Simultaneous herbicide applications of residual BCST + foliar SS, base-rate foliar BCST + SS “Spike” rates, and SS only were compared in corn (Zea mays L.) and soybean trials. Specific SS thresholds tested included an herbicide efficacy, balanced, savings, and traditional BCST applications were tested for comparison. Results showed that both residual BCST + foliar SS and “Spike” approaches provided weed-free area not different than traditional broadcast applications, in many cases. The greatest savings were achieved by SS only applications, but weed-free area was almost always significantly less than for other treatments. Simultaneous BCST + SS of soil residual and foliar herbicides, respectively, provided the most weed-free area with the greatest cost savings for both crops. Thirdly, we tested a commercial-sized ONE SMART SPRAY and compared traditional broadcast applications with SS only and simulated two-boom/two-tank applications using the foliar base rate + “Spike” approach. Treatments included SS only, low rate BCST + high rate SS, and high rate BCST + low rate SS applications. Results indicated that high rate BCST + low rate SS applications provided the highest weed-free area, but savings were not different from a broadcast application in soybeans. In corn, thresholds were not different, but both applications with BCST applications demonstrated greater weed-free area than SS only treatments. Overall, this research demonstrated that 1) open-sourced object detection algorithms can be custom trained to identify A. palmeri in soybean crops, with opportunities to train and identify other weed species in other crops, 2) intelligent AI sprayers show potential in providing weed-free area comparable to traditional BCST applications, especially systems that utilize two-tank/two-boom technology for simultaneous BCST and SS applications, and 3) herbicide costs were significantly reduced for SS applications compared to traditional BCST applications.
