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Diffusion Mechanisms, Measurements, and Models with Applications in Bioremediation of Trichloroethylene and Breakdown Products
No full textTrichloroethylene (TCE) is a persistent groundwater pollutant remaining from decades of use as a dry cleaning solvent and general degreaser. Having low solubility and a higher density than water, it often exists as a Dense Non-Aqueous Phase Liquid (DNAPL) at the bottom confining layer of aquifers, posing a unique remediation challenge. Bioremediation using anaerobic bacteria has proven successful, but high concentrations of TCE and proton buildup from degradation can incapacitate microbes, leaving the system “stuck”. In addition, incomplete degradation of TCE results in by-products cis-1,2-dichloroethene (cDCE) and highly toxic vinyl chloride (VC). Encapsulation of microbes in a hydrogel bead to facilitate diffusion of pollutant and adsorption of acid may allow total remediation of problem systems. In this work, a series of membranes of various compositions are tested and diffusion coefficients determined for all species of interest using the diaphragm cell method. In Chapter 3, this information is used in a model to optimize hydrogel bead size and composition for bioremediation applications. Laboratory measurements of diffusion coefficients are time-consuming and may not be feasible for a diverse range of membrane types. It would be highly advantageous to build a correlation relating membrane properties to diffusivity. This would eliminate the need for repeated measurements using hazardous chemicals. Such a model would also allow rapid estimates of diffusion coefficients, expanding the likelihood of adoption of diffusion/reaction systems. Chapter 2 relates solute size, charge, and interactions within hydrogel membranes to steady state effective diffusivity for several molecules including hydrochloric acid. Increased understanding of the mechanisms of proton diffusion may have applications beyond bioremediation, including fuel cells and biomedical implants. Chapter 4 details future work which may improve efficacy of encapsulated cell systems.masters, M.S., Chemical and Materials Science Engineering -- University of Idaho - College of Graduate Studies, 2020-0
Self-Reported Total Vegetable Intake, but not Fruit, is Associated with Higher Cognitive Test Scores Among University Students
No full textFruit and vegetable (F/V) consumption throughout the lifespan plays an important role in maintaining optimal physical health; however, additional research focusing on college students is needed. University of Idaho students (n=23) participated in this cross-sectional study to investigate relationships between dietary F/V intake and 1) cognitive outcomes, 2) psychological well-being, and 3) skin carotenoid concentrations. Dietary F/V intake was assessed using the Automated Self-Administered 24-hour (ASA24) Dietary Assessment Tool (version 2018). Cognitive and emotional outcomes were assessed via the NIH Toolbox® for Assessment of Neurological and Behavioral Function (NIH Toolbox). Skin carotenoid concentrations were estimated using Resonance Raman spectroscopy (RRS). Spearman’s correlations (with and without an income adjustment) were used to evaluate relationships between variables using SAS software. Cognitive scores were adjusted for age, gender, race, ethnicity, educational attainment, and parent education. Higher processing speed was associated with higher total vegetable intake (R2=0.56, p=0.01) and higher combined F/V intake (R2=0.43, p=0.04) with the added income adjustment. Intake of dark-green vegetables positively correlated with executive function (R2=0.42, p=0.05), as well as processing speed (R2=0.45, p=0.04) and fluid cognition (R2=0.48, p=0.02). Additionally, consumption of foods rich in lycopene positively correlated with processing speed (R2=0.43, p=0.05) and fluid cognition (R2=0.41, p=0.05). While there was no significant relationship between F/V consumption and skin carotenoid scores, there was a significant positive relationship between skin carotenoid scores and dietary intake of beta-carotene (R2=0.50, p=0.01), lycopene (R2=0.42, p=0.05), and total carotenoids (R2=0.72, p=0.0001). There was no association between total dietary F/V intake and emotional health measures; however, consumption of dark-green vegetables, consumption of legumes, and skin carotenoid sores were inversely related to negative affect (R2=-0.45, p=0.04; R2=-0.42, p=0.05; R2=-0.50, p=0.02, respectively). Legume intake and skin carotenoid scores were also positively related to psychological well-being (R2=0.44, p=0.04; R2=0.48, p=0.02, respectively). Results of this study suggest a relationship between dietary intake of total vegetables and higher processing speed scores, but no relationship between total fruit and cognitive outcomes. Further research with larger sample sizes is needed to comprehensively evaluate these relationships among university students.masters, M.S., Family and Consumer Sciences -- University of Idaho - College of Graduate Studies, 2020-0
Molecular Mechanisms Governing the Differential Regulation of Tandemly Replicated Visual Opsin Genes
No full textOur sense of sight is the primary way humans interface with our surroundings. A significant portion of the human brain is devoted to detecting and processing visual stimuli. Vision is made possible by a specialized structure of the central nervous system called the retina located at the back of the eye. Color vision is made possible by specialized cells called cone photoreceptors in the outer most layer of the retina. Humans have three subtypes of cones red, green ,and blue. The subtype is determined by the expression of opsin proteins that are sensitive to specific wavelengths of light. These are short wavelength sensitive (SWS; blue), medium wavelength sensitive (MWS; green), and long wavelength sensitive (LWS; red). Enormous efforts have been made in deciphering how these cone subtypes are determined. Understanding of the regulatory processes involved in the determination of cone subtypes will provide the knowledge required to identify factors that may disrupt normal development of the visual system and may potentially provide insight into the creation of novel therapeutics designed to treat a multitude of visual disorders that specifically involve cone photoreceptors. This body of work begins with an overview of retinal development, structure, and function. Next, I present my published work that has identified the nuclear signaling molecule thyroid hormone (TH) as an endogenous regulator of unique visual opsin genes in zebrafish called tandemly replicated opsin genes. Tandemly replicated genes are the result of a duplication event that results in two or more functionally related genes that are found next to each other in the genome and are regulated by the same upstream regulatory regions. These include the tandemly duplicated lws1/lws2 array and the tandemly quadruplicated rh2 array. Chapter 3 describes unpublished work in which I identify regions of the lws locus that are required for regulation by TH including two potential response elements that are critical for the differential regulation of lws1 vs lws2 in response to TH. Next I present incredible findings that detail the involvement of TH in the differential regulation of the tandemly duplicated LWS/MWS visual opsin array found on the X chromosome in humans. I also present preliminary findings in zebrafish that identify specific nuclear signaling receptors that contribute to the differential regulatory mechanism governing expression of the tandemly replicated visual opsin arrays. This body of work significantly expands upon our understanding of how cone subtypes are determined and the components of the regulatory mechanisms involved in making this determination.doctoral, Ph.D., Biology -- University of Idaho - College of Graduate Studies, 2020-0
Triple Bottom Line Approach to Community Sustainability and Cohesion: A Conceptual Framework
No full textSustainable development has become both a key policy objective for community development agenda and a significant public matter. Coherent policy development and productive public debates are, however, both threatened by the fact that the concept of sustainability is used with widely differing measures. Based on a review of related literature and primary fieldwork in settings of organizational literature, a framework linking three domains is presented as a tool to foster success and measure regarding normative conceptions of sustainable development in community settings. This paper identifies elements central to perceptions of what constitutes ‘successful’ measure of community sustainable development. Key domains of integration are proposed related to three bottom lines: Economic, Social, and Environmental. This analysis introduces a conceptual framework and model as a measure for community sustainability drawing from the triple bottom line (TBL) accounting framework or theory which recommends companies to commit giving the same weight of focus to social and environmental concerns the same way they do on profits by focusing on three bottom lines representing, People, Profit, and Planet as a whole instead of focusing on Profits alone. Results indicate a significant presence of community cohesion with residents giving equal consideration to all three bottom lines as a measure of community quality.masters, M.S., Agricultural Economics and Rural Sociology (Applied Economics) -- University of Idaho - College of Graduate Studies, 2020-0
Everything in the Universe is either a Potato or not a Potato: Solving for Optimal Crop Rotations through Linear Programming
No full textPotatoes are a major commodity for the United States as well as Idaho. However, growing potatoes comes at a cost of diminishing soil quality. Diminished soil quality can impact profits due to decreased yields and quality. Crop rotations help potato growers maintain soil quality while focusing on maximizing average annual returns. Through linear programming optimal crop rotations are found for maximizing net present value. These optimal crop rotations are then run through a Monte-Carlo simulation to characterize the price risk of these different rotations. The linear programming and Monte-Carlo models are also compiled into a simple dynamic functional excel tool. It is found that all of the top five-year crop rotations in NPV consist of potatoes in the first, third, and fifth years. There is little difference in the NPV of these top crop rotations. As potatoes consist of the majority of the rotations’ NPV what is grown in the years without potatoes has little impact on the total NPV. This indicates the importance of the crops grown besides potatoes having a positive impact on the soil health and in turn having a positive impact on the yields and quality of the potato harvest. The monte-carlo simulation results in small difference in the price risk of these different crop rotations. This again supports the importance of the other crops impact on potatoes as there is no significant difference in the price risk of the varying crop choices. The dynamic excel tool created will be able to further this research with more information on what the impact crops have on each other in terms of the quality and yields. This tool will be able to be used by researchers to further the research done within this thesis, as well as by producers as a decision-making tool for helping to find the crop rotations that will maximize NPV.masters, M.S., Agricultural Economics and Rural Sociology (Applied Economics) -- University of Idaho - College of Graduate Studies, 2020-0
An Exploratory Assessment of Soil Moisture Regime Delineations in the Pacific Northwest
No full textCreated concurrent with Great Plains cropping systems along a shallow precipitation gradient, the translation of soil moisture regimes (SMRs) to the American West may not account for the latter’s variable precipitation distribution and natural vegetation. While this was noted shortly after the regimes’ genesis, Western land managers were still left to infer SMRs along vegetative communities using Great Plains definitions and field knowledge alone. To ground truth these vegetative associations with SMR definitions, four transects of five monitoring sites each were placed along gradients of increasing precipitation to capture respective transitions from aridic to xeric and xeric to udic SMRs within relevant plant communities and land uses of Major Land Resource Areas (MLRA) 2 & 3, 10, 12, and 43A. MLRA 10 was predicted to traverse aridic and xeric SMRs while the remaining transects would represent the transition from xeric to udic. Sites representing MLRAs 2 & 3 were all measured as having a udic SMR. Within MLRA 10, sites were measured as having a udic SMR. MLRA 12 was the most diverse, containing ustic, aridic, and udic SMRs at sites 1 and 2, 3 and 4, and 5, respectively. Finally, MLRA 43A, was measured as having a udic SMR at sites 2-5 and an ustic SMR at site 1. Though 10 years of data is necessary to officially assign a SMR, the radical misalignment between predicted and actual SMRs indicates that either regime definitions do not adequately reflect significant changes in Western vegetation as depicted by local land managers, or vegetative delineations need to adjust to fit instated SMR definitions. Considering the former, when setting the soil moisture threshold to 10% volumetric soil moisture instead of the current wilting point volumetric soil moisture, the predicted soil moisture regimes better fit actual soil moisture measurements. Regardless, more monitoring is necessary to take definitive action.masters, M.S., Plant, Soil and Entomological Sciences -- University of Idaho - College of Graduate Studies, 2020-0
Arbor Notes April 2020
No full textThis April publication includes the subject headings: Walk with Jane Austen; Message from the President; Calendar of Upcoming Events; Arboretum Associates Annual Plant Sale; 19th Annual Summer Concert; Dr. Richard J. Naskali Asian Section; Arboretum Associates Donor Roll; Report from the Horticulturist; Something New on the Red Barn; Paul Anders will be Missed; Science Saturdays 2019; City of Moscow Plein Air Demonstration; Water Wise Inspiration and Desig
Biochemical and Physiological Effects of Organic and Inorganic Zinc in a Commercial Strain of Diploid and Triploid Rainbow Trout (Oncorhynchus mykiss)
No full textZinc is an essential micro-mineral for fin fish and is required for a wide range of physiological functions. Bioavailability of minerals in diets depends on quality and source. Finding chelates that are more bioavailable to fish can help decrease production costs and metal waste pollution. In aquaculture, triploid fish can be utilized for their sterility to decrease risk of genetic pollution and for their potential for faster growth. However, zinc requirements may differ between ploidies due to physiologic differences and to our knowledge there is no information regarding zinc requirements for triploid Rainbow Trout. These experiments aim to determine the effects of supplemental zinc in a commercial strain of genetically similar diploid and triploid Rainbow Trout (Oncorhynchus mykiss, average initial weight: 53.07 ± 4.35g) using various levels (63, 93, 123, 153, 183 mg kg-1 Zn) of both organic and inorganic zinc. A total of 11 diets were formulated to be isonitrogenous (42% crude protein) and isolipidic (21% lipid), and fed in triplicate for 64 days. Results showed that neither ploidy (diploid vs. triploid) nor type of mineral (organic vs. inorganic) significantly influenced the growth performance of fish, distal intestine histology, or cataract formation/lens histology. However, there were significant interactions in nutrient retentions and vertebral zinc content for both ploidies. Additionally, there were significant differences in oxidative stress related gene expression patterns in hepatocytes, supporting evidence for a mechanism of zinc’s role in the antioxidant defense system of Rainbow Trout. Gene expression was generally higher in response to organic zinc in triploids than in diploids, suggesting that diploid and triploid Rainbow Trout have different zinc requirements. These findings also establish a relationship between dietary zinc and the retention of zinc and other macronutrients, such as lipid and protein, and the oxidative stress response in diploid and triploid rainbow trout. Increased supplementation of organic zinc may aid diploid and triploid Rainbow Trout in superior utilization of macronutrients in feed and increased capacity to combat oxidative stress.masters, M.S., Animal and Veterinary Science -- University of Idaho - College of Graduate Studies, 2020-0
Hierarchical Inference and Spoofing Alarm in HVDC Control Systems
No full textThe study of HVDC systems and cyber-attacks on their control systems can play an important role in the security and stability of large interconnected power systems. This work develops and analyzes a layer of security useful to detect and mitigate the negative impact of cyber-attacks directed towards high voltage direct current (HVDC) systems. It also identifies and categorizes potential attack types which may be harmful to power system operation if left unmitigated. Minimization of transients induced by remediation action are also addressed through the use of a classic control system technique: the bumpless transfer. Contained in this thesis is a summary of the testing performed on a HVDC cyber physical simulation environment, the performance of the security algorithms in terms of timing, detection rate, and relationship with false detection. Successful implementation of the approaches developed in this thesis can help allow the HVDC system to enhance resilience of the interconnected power system in the face of cyber-attacks.masters, M.S., Electrical and Computer Engineering -- University of Idaho - College of Graduate Studies, 2020-0
Design and Experimental Analysis of a Large Scale Natural Convection Test Loop
No full textThis thesis presents the design, development, and preliminary testing for a natural circulation test loop at the University of Idaho. The loop stands 19-ft tall, and is designed to handle high temperatures and pressures. To use the loop, a heater and heat exchanger were developed to add and remove heat at the same rate. A 4 kW immersion heater adds heat, and a custom tube-in-tube heat exchanger removes heat. A pressurizer and control system was also designed for higher pressure tests. A pump, valve, and flow meter combination were used to the flow of cooling water, and thus the heat removed. Temperature profiles were analyzed for low pressure tests (48 kPa, 7psi) and high pressure tests (1724 kPa, 250 psi). Heat exchanger temperature profiles were also measured and heat exchanger effectiveness determined. Results show reasonable agreement with CFD results from other studies. Suggestions for improving the loop are also given.masters, M.S., Nuclear Engineering -- University of Idaho - College of Graduate Studies, 2020-0