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The Seeds of Morrow
No full textThis thesis is a reflective overview of my artistic research and practice within which I discuss my multi-disciplinary body of work consisting of sculptural ceramics, found-object installations, video, and live performance. Reflections on our interconnected relationship with our natural resources, our sense of home, and the impacts of our origins are major themes in my work. Various visual metaphors and iconography are used to reinforce deeper meanings. This work created in pursuit of my MFA culminated in my Thesis Exhibition, “The Seeds of Morrow” shown in the Prichard Gallery in Spring 2021.masters, M.F.A., Art & Design -- University of Idaho - College of Graduate Studies, 2021-0
Extending the Shelf-life of Beef Steaks Using Acerola Cherry Powder and Rosemary Extract in Order to Remain Competitive in the International Market
No full textImprovements in retail shelf-life of exported beef will help with merchandising and increase the competitiveness of US beef products in the global market. The objectives of these studies were to 1) determine the effect of the topical application of 0.05% acerola cherry powder (C) and 0.10% rosemary extract (R) from various suppliers (1, 2, 3) on beef chuck roll and bone-in short rib steak retail shelf-life and 2) determine the effect of the topical application of 0.05%-0.10% acerola cherry powder and 0.10%-0.20% rosemary extract in combination on beef chuck roll and bone-in short rib steak retail shelf-life. Chuck roll steaks treated with R1 and R2 had a brighter oxygenated lean color than untreated control steaks, while C2 and R2 treated steaks were more uniform than untreated control steaks. R3 improved short rib bone marrow redness and yellowness, and C1 brightened short rib steak oxygenated lean color. When combining antioxidants, chuck roll steaks had improved redness and higher concentrated combinations delayed lipid oxidation. In short rib steaks, antioxidant combinations delayed lipid oxidation and improved oxygenated lean color. Applying topical antioxidants can improve retail shelf-life stability of beef chuck rolls and bone-in short ribs aged for an extended period.masters, M.S., Animal and Veterinary Science -- University of Idaho - College of Graduate Studies, 2021-0
Genomics of Rapid Evolution in the Tasmanian Devil (Sarcophilus harrisii) and Tamarisk Beetles (Diorhabda spp.), Wild Populations of Management Concern
No full textWe now recognize the pervasiveness of rapid evolution in the wild; yet it remains a challenge to identify the key patterns and processes to predict outcomes and inform management decisions. In this dissertation, I employ genomic tools and multi-scale analyses over molecules, space, and time to improve our understanding of the genomic context of rapid evolution in two systems of management concern: the Tasmanian devil, Sarcophilis harrisii, and a classical biological control (biocontrol) agent, the tamarisk beetle (Diorhabda spp.). In these taxonomically-distinct systems, the common management goal is essentially to allow or provide beneficial genetic variation for adaptation to novel selective forces while limiting the potentially adverse effects of fixation and introgression. By spanning the tree of life and the unique circumstances of these systems, we can better identify strategies informative to systems of management concern. Tasmanian devils (Sarcophilus harrisii) are evolving in response to a unique transmissible cancer, devil facial tumor disease (DFTD), first described in 1996. Persistence of wild populations and the recent emergence of a second independently evolved transmissible cancer suggest that transmissible cancers may be a recurrent feature in devils. In Chapter 1, I use range-wide RAD capture data and publicly available marsupial genomes to compare signatures of selection across temporal scales. I test the hypothesis that genes or gene pathways under contemporary selection have also been subject to historical selection. I documented genome-wide contemporary and historical selection, but limited evidence of recurrent selection, with no functional enrichment shared among gene sets. My results are consistent with a novel, polygenic evolutionary response of devils to DFTD and can inform management actions to conserve adaptive capacity of devils by identifying high priority targets for genetic monitoring and maintenance of functional diversity. In Chapter 2, I examine the genome-wide outcomes of introduction, spread, and gene flow in the four cryptic species of the tamarisk beetle (D. carinata, D. carinulata, D. elongata, and D. sublineata), introduced to control invasive tamarisk (Tamarix spp.) in North America. I assembled a de novo draft reference genome of D. carinulata and used reference-based RADseq to characterize the genetic variation associated with establishment, spread, and gene flow. I found differential establishment and spread among the six released populations. Despite evidence of a substantial genetic bottleneck among collections of D. carinulata in North America and low levels of genetic diversity, populations continue to establish and spread, with one ecotype dominating the southward expansion front.¬ I confirmed that Diorhabda hybridizes widely in the introduced range. Genetic diversity was greater in populations with hybrids, highlighting potential for increased adaptive capacity. These results provide a snapshot of introduced Diorhabda populations and lay the foundation for further application of genomics to understand contemporary eco-evolution in classical biological control programs. In Chapter 3, I present high-quality assemblies of all four Diorhabda species using iterative, third-generation sequencing technologies, in collaboration with the United States Dep. Agriculture, Agricultural Research Service Ag100 Pest Initiative. I annotate these nearly chromosome-level assemblies with population genetic data to validate sex chromosome identification, compare the arrangement of single-copy orthologs, and characterize repeat content among the introduced biocontrol species. These resources dramatically improve our ability to identify mechanisms of rapid evolution in reproductive barriers, adaptation to novel environments, and physiological responses to plant hosts.doctoral, Ph.D., Bioinformatics & Computational Biology -- University of Idaho - College of Graduate Studies, 2021-0
An Energy Absorption Investigation of CFRP Composite Thin-Walled Tubes with PVC Foam-Filled Cores
No full textToday, thin-walled (TW) structures are known for their use in several fields such as aerospace, automotive, rail, and maritime. With the growing concern for life-threatening terrorist attacks, these structures have been studied for their use in structural engineering as well, as part of protective structural systems. With the goal of achieving excellent crashworthiness performance with the minimum possible weight, systems comprised of lightweight materials with high strength-to-weight properties are subjects of study. The primary objective of this study is to investigate the effect of carbon fiber reinforced polymers (CFRP) and polyvinyl chloride (PVC) foam reinforcements on the crashworthiness of tall, thin-walled circular aluminum tubes, to be used as energy absorbers. This investigation was done by experimentally testing tubes with inner diameter of 60 mm, wall thickness of 1.6 mm, and 120 mm in length with different reinforcement configurations under quasi-static axial loads. The effect of epoxy on energy absorption capability was investigated to determine whether adhesives are to be used to bond the tube wall and the foam core or not. In addition, tubes with CFRP and PVC foam reinforcing configuration and varying lengths (40 mm, 80 mm, and 120 mm) were tested to determine the most efficient configuration with tubes of different length-to-diameter ratios (L/D).The study concluded that CFRP and PVC foam reinforcements increase the energy absorption of tall aluminum tubes by 37% and the peak force by 20% compared to the control, unreinforced, aluminum tubes. Also, these reinforcements were found to have complementary effects on energy absorption capabilities of aluminum tubes. Although epoxy adhesion between the foam core and tube wall was found to increase the peak load by 2%, it does not improve energy absorption while increasing the mass of the specimen by 9%. The CFRP and PVC foam reinforcing configuration was found to be equally effective for tubes between 80 mm (L/D = 1.33) and 120 mm (L/D = 2.00) with a proportional increase in energy absorption with an increased length. However, it was found that the smaller the specimen, the higher the peak load.masters, M.S., Civil Engineering -- University of Idaho - College of Graduate Studies, 2021-0
N-HEPTANE AUTOIGNITION AND SPECIATION IN A NOVEL RAPID COMPRESSION EXPANSION MACHINE
No full textThis work examines the autoignition chemistry of fuel-lean n-heptane oxidizer mixtures. A Rapid Compression Expansion Machine (RCEM) was used to obtain both ignition delay times and study the stable intermediate species time evolution during the induction period. Ignition delay times for premixed fuel-oxidizer mixtures were obtained for compressed pressures between 3.0–5.5 bar and equivalence ratios (ϕ) between 0.20 and 0.50. The compressed temperatures were in the range of 592–763 K and included the onset of the negative temperature coefficient behavior for n-heptane under these test conditions. Trends for both the first-stage and overall ignition delay times as a function of temperature were obtained.Additionally, the identification and quantitation of pre-ignition stable intermediaries were conducted. This was accomplished by rapid quenching of the reactions after the first-stage ignition phase in controlled time increments. A gas chromatograph-mass spectrometer system was used for the identification and quantification of stable intermediates. This work provides fundamental insights into the low-to-intermediate temperature oxidation kinetics of n-heptane using a new generation of electrically actuated and computer programmable RCEM.masters, M.S., Mechanical Engineering -- University of Idaho - College of Graduate Studies, 2021-0
Examining Global Competency and Content Knowledge of Secondary Agricultural Educators and Students Before and After the Implementation of a Globally Centered Curriculum Thesis
No full textPreparing students for a globally connected world starts with giving the right tools and training to pre-service and in-service teachers and providing them with relevant competencies that are needed to create a globally connected curriculum. The globalization of agriculture means there is an emerging need for agricultural education in the United States and an increase in a globalized approach to prepare students for future agricultural careers. Teacher education programs have lagged in higher education in terms of internationalization, which could lead to teachers who feel unready to incorporate international issues. To address this problem, the study will allow for an investigation of the global competencies for Pacific Northwest (PNW) agricultural educators and examine needs they have to be successful when integrating this global curriculum into their classrooms. The findings revealed that there were differences in the scores between the different sites and the different demographic factors between the secondary agricultural education students. An examination of the pre/posttest with Global Citizenship Scale and the Global Content Knowledge Assessment showed higher change in scores between the different grade levels and age groups between the students. The findings for the secondary agricultural educators were limited, however shed a light on how different educators scored on their pretest before delivering the instruction to their students. From these findings, this study points to the need of the integration of global agriculture concepts in the classroom through a Global Citizenship model. There needs to be a creation of a scope and sequence model for PNW secondary agricultural educators to follow with the creation of new and relevant lesson plans and activities to incorporate into different programs. This research found that there was a significance to the implementation of this curriculum to the different sites that were selected which showed growth between the students before and after the implementation of the Global Agriculture Citizenship unit.masters, M.S., Agricultural Education & 4H Youth Development -- University of Idaho - College of Graduate Studies, 2021-0
Western U.S. Forest Carbon Balance in the 21st Century: Improving Projections with Improved Disturbance Monitoring and Modeling
No full textThe forests of the western United States face profound impacts from shifts in climate, natural disturbance regimes, and land management in the 21st century. Under novel conditions, forest ecosystem services will be altered, including impacts to forest climate moderation, resource provision, and biodiversity. However, the complex processes that determine present-day observed forest structure and composition across the complex terrain of the region are incompletely understood. As a result, scientists and land managers are confronted with considerable uncertainty as to how widespread natural and human impacts upon forests will result in changed processes and states. This dissertation employs model-observation frameworks to examine and improve upon the understanding of how disturbance will impact western U.S. forest carbon balances from site to regional scales. Chapter 1 addresses deficiencies in current process model representations of direct emissions and ecosystem mortality transfers during forest fire. In this study, I incorporate novel observations and modify an ecosystem biogeochemical model to compare to model default assumptions. Projected carbon balance impacts of observation-based vs model-based assumption are then quantified in: 1) A carbon dense forest via a modified Daycent biogeochemical model; 2) Across the western United States from 2000-2016. At the state level, model default assumptions lead to 50-110% overestimates in carbon emissions, primarily due to the unrealistic combustion of live tree bole biomass and compounded by a lack of standing-dead biomass pool representation. Projections demonstrate that emissions overestimates can increase to 300-500% in carbon dense forests (e.g. old growth) in the midterm (30 years) due to altered decomposition. Chapter 2 quantifies the carbon and water balance impacts of an experimental selective thinning in a ponderosa pine forest in the University of Idaho Experimental Forest. I use automated and traditional ecosystem stock and flux measurements to estimate the impacts of treatments from 2016-2019 at contrasting tree and stand scales, with a focus on the balance between primary producer density reductions and mitigated summer drought stress. I then project the on and off-site carbon balance impacts of treatment through 2050 with a life cycle assessment (LCA) and with the Daycent biogeochemical model. Projections allow the exploration of whether carbon parity with control stands is reached within common emissions reduction time periods. Observations indicated an average 30% increase in thinned stand residual tree growth. In contrast to the control stand, treated stand tree transpiration persisted through the summer drought period. However, production and water use increases did not compensate for tree density reductions and both yearly Net Primary Production (NPP) and transpiration decreased in treatment stands. Projections demonstrated that large harvest-event emissions pulses from long-lived woody biomass pools led to long carbon deficit legacies; treatment carbon storage parity with control stands was not reached by 2050. Chapter 3 employs a dynamic global vegetation model (DGVM) to simulate chapter 2 stand dynamics and examine model applicability for simulations across a northern Rocky Mountain ecoregion domain. The FATES DGVM simulates forest composition and structure, disturbance regimes, biogeochemistry, and biophysics, operating within the Community Land Model 5 (CLM5) of the Community Earth Systems Model (CESM). I examine FATES dynamics in the context of: 1) Variable intensity selective harvests; 2) Historical and future control and treatment stands; and, 3) sensitive input parameter variation.doctoral, Ph.D., Natural Resources -- University of Idaho - College of Graduate Studies, 2021-0
Bobby Chamber Memorial Highway
No full textSign for the Bobby Chambers Memorial Highway near Potlatch