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The Relationships Between Self-efficacy, Social Support and Physical Activity in Chinese College Students
No full textThe complex mechanism on how intrapersonal and interpersonal components are associated with physical activity under the framework of the Ecological Systems Theory is intriguing, but few studies have shed lights on it in Chinese college populations. This study examined the structural relationships between self-efficacy, social support and physical activity among Chinese college students. A total of 460 Chinese college students (254 men and 206 women) completed the questionnaires assessing self-efficacy, social support from family and friends, and physical activity in the domains of work, travel and recreation. The Structural Equation Modeling was used to investigate how social support from family and friends were directly and indirectly associated with physical activity when self-efficacy acted as the mediator. The results suggested that self-efficacy fully mediated the relationships between social support from friends and recreational physical activity, while social support from family was directly associated with work, travel and recreational physical activity. In addition, female students reported lower self-efficacy and less work and recreational physical activity than male students. Students in higher grade engaged in less travel and work physical activity than those in the lower grade. This study aided in the understanding of how self-efficacy and social support may predict physical activity behaviors in different domains among Chinese college students. Health educators should consider the interpersonal and intrapersonal factors as a useful combination when promoting physical activity in college settings.doctoral, Ph.D., Movement & Leisure Sciences -- University of Idaho - College of Graduate Studies, 2019-1
Assessing Plant Community Attributes Along Environmental Gradients in two Critical Landscapes
No full text""The wilderness and the idea of wilderness is one of the permanent homes of the human spirit” Joseph Krutch (1995) ""Wilderness itself is the basis of all our civilization. I wonder if we have enough reverence for life to concede to wilderness the right to live on?"" Margaret Murie Human activities contributing to the accumulation of greenhouse gasses in the atmosphere have created a rapid spike in surface temperatures leading to major shifts in ecological processes (Walther et al., 2002). Changes to abiotic cycles are affecting biological communities however, not all species will respond the same way. Changes to colonization and extinction rates are leading to novel communities and functional compositions, further altering ecosystem processes. (Díaz, S., & Cabido, M., 1997). Our current state of urgency regarding climate change mitigation demands a better understanding of ecosystem responses. Relative to other landscapes, wilderness areas offer a rare opportunity to study ecological processes in a setting affected little by direct human manipulation. Studying naturally functioning systems provides a frame of reference for addressing baseline ecosystem health and can inform better management decisions (Sharman, Landres, & Boudreau, 2007). Protected under the wilderness act, wilderness areas also provide the opportunity for long-term landscape-level studies (Six et al.,2000). Wilderness areas are critical landscapes not only as the last living laboratories to study natural ecological processes but, as a necessity to the human spirit. Research shows that more life-sustaining, intrinsic, future, and spiritual values are associated with wilderness areas than outside of these areas (Cordell et.al., 1998; Cordell, Bergstrom & Bowker, 2005). Based on a survey of 5,000 Americans by Cordell, Torrant and Greene (2003), the level of importance placed on wilderness values has increased in the 21st century compared to a 1995 survey. Beyond engaging in research on natural systems, we have a responsibility to protect our remaining wilderness areas. The first two studies of this thesis take place in the heart of the Frank Church- River of No Return (RNR) Wilderness at one of the most remote research stations in the country. Taylor Wilderness Research Station was first established as a homestead by Dave Lewis in 1879 (Dave Lewis Papers). Prior to that, the area was a piece of the homeland inhabited by the Tukudeka (Frey & McCarl, 2014). Overtime, the rugged mountainous terrain, carved out by swift rivers, under a semi-arid climatic regime has shaped both social and ecological attributes of the communities existing within this landscape. A baseline study of plant community dynamics was conducted from the Taylor Ranch Wilderness Research station at an elevation of 3,800 ft to the summit of Dave Lewis Peak at 9,200 ft. This study aims to provide a snapshot of the current state of vegetation communities to help better understand how this biologically and culturally rich landscape will adapt and transform in our changing climate. The third study takes place in a remote valley on the island of Kauai, HI under preservation by the National Tropical Botanic Gardens. This landscape is critical due to its conservation of rare, threatened and, culturally significant plant species in addition to its reputation as the longest remaining biocultural unit managed under the traditional Hawaiian system of land management. After a severe rainstorm event in April of 2018, flooding and landslides devasted the valley and isolated the community of Ha’ena. During this unique time in history, I had the opportunity to observe the social and ecological community dynamics after a major disturbance driven by climate change. Together, these chapters comprise an exploration of community dynamics from a social and ecological perspective in the midst of climate change. In the first chapter, we analyze plant community characteristics in addition to phylogenetic and functional diversity patterns along an elevation gradient in a remote wilderness setting. The second chapter adds to this baseline study an investigation of floral scent composition from Penstemon species, an endemic North American taxon. In the final chapter, plant community composition and functional diversity during early succession are compared to intact communities after a recent landslide within a highly manipulated system. Woven into these chapters are aspects of my personal experiences, observations of cultural dynamics and historical accounts. With these underlying notes of human interactions with the natural world, the aim of this thesis is to explore plant community dynamics in critical landscapes from a perspective recognizing that changing landscapes will shift both social and ecological aspects of communities. The overarching goals of this project include: 1. To continue to understand these critical landscapes by collecting baseline data in order to be better stewards of the land. 2. Expose some of the cultural ties to these landscapes which are equally important with ecological aspects when considering conservation strategies.masters, M.S., Natural Resources -- University of Idaho - College of Graduate Studies, 2019-1
Glucosinolates and Glycoalkaloids as Biopesticides
No full textDevelopment of alternative pest control methods is a pressing issue as more species of pests develop resistance to synthetic pesticides and public demand for organically grown produce increases. Our research is focused on development of biopesticides from plant glycosides such as glucosinolates found in the family Brassicaceae and glycoalkaloids found in the genus Solanum. To achieve this goal, we use bioassay-guided methods for extraction and isolation of biologically active compounds from plant material. We then fractionate and analyze plant extracts with the highest pesticidal activity using chromatography coupled with mass spectrometry. The use of time of flight mass spectrometry allows for the accurate mass assignment and in silico compound identification. For example, we have identified several glycoside hydrolysis products in Brassica juncea and Solanum sisymbriifolium that exhibit nematicidal activity. We have also demonstrated that at least two different compounds are responsible for herbicidal activity of Sinapis alba towards three model weeds. Finally, we designed a bioprocessing pilot plant for efficient and cost-effective production of biopesticide formulations.masters, M.S., Plant, Soil and Entomological Sciences -- University of Idaho - College of Graduate Studies, 2019-1
Military Surplus and Modern Policing: A Spatial Analysis of Police Usage of the Federal 1033 Program
No full textWhile there have been long-running concerns over police militarization in the United States, the aggressive police response to the 2014 protests in Ferguson, Missouri heightened public awareness of the issue. As a result, the police acquisition and use of military-style equipment has come under increasing scrutiny, as have the programs which provide police access to such equipment. The 1033 program, which provides military surplus to civilian police, is perhaps the most important and controversial such program, and participation in 1033 is often seen as an indicator of the adoption of military-like practices by police. This study is situated to build upon previous geographic work on the police militarization and the 1033 program (Radil, Dezzani, and McAden, 2017) by exploring those contextual influences of place on Law Enforcement Agency (LEA) decision making. This previous research showed that participation in the 1033 program has been highly regionalized and proposed that local and regional contexts have important explanatory value. To build on this, three groupings of contextual elements of place were identified as having the greatest potential to influence LEAs, and consisted of; socioeconomic contexts, measurable political and legal factors, and measures of LEA structure and activity. To deal with the spatial variation present in these local and regional contexts, a geographically weighted regression (GWR) model was used to explore the influence of place on LEA decisions to participate in the 1033 program. The highly regionalized findings in this study deviated from the common global argument for why police become militarized. This deviation supports the need for further spatial research into not only police militarization but policing in general.masters, M.S., Geography -- University of Idaho - College of Graduate Studies, 2019-1
Ionizing Radiation Sensitivity of Hydroxyl Terminated Polybutadiene Solid Propellant
No full textThe effects of ionizing radiation on hydroxyl-terminated polybutadiene (HTPB) solid propellant are investigated to assess its sensitivity to electron radiation. Investigation into the radiation sensitivity of HTPB propellant is needed to assess potential risks to a mission aimed at landing a craft on the surface of Jupiter’s moon Europa, considering this region of space has very high particle radiation fields. This mission would require deploying a Europa Breaking Motor (EBM) using HTPB propellant to provide the necessary deceleration to safely land a craft on Europa’s icy surface. The current concept for an EBM requires motor components, including the propellant, to have a radiation sensitivity of no less than 2.4 Mrad. While HTPB solid propellant has been studied and used in rockets to place satellites in orbit and for military applications, it has not been previously investigated to support, with sufficient confidence, missions to Jupiter’s moons. Tensile data from surrogate propellant, binder, hybrid propellant and HTPB propellant are used to derive values for radiation sensitivity on the basis of crosslink density, particle adhesion, debonding and damage to the aluminum and ammonium perchlorate. Using the Flory – Rehner and Mooney – Rivlin models, the propellant’s limiting value for crosslink density is computed with its corresponding radiation dose. The Pukansky model is used here to obtain a limiting value for the propellant bonding factor and its corresponding radiation dose. Similarly, the Nicolasis – Narkis model is use to derive values for the propellant’s particle adhesion factor and its corresponding radiation dose. Lastly, the Goodier model is applied to derive the maximum load on the aluminum and ammonium perchlorate in the propellant with their corresponding radiation dose. The computed values for radiation dose obtained from these models were then compared to the radiation sensitivity value for the EBM components of 2.4 Mrad. The results from these models show ammonium perchlorate to have a radiation sensitivity that will not support the current motor concept in relation to the 2.4 Mrad requirement. This, in turn, necessitates further refinement of the EBM design to possibly provide shielding in the case liner for the propellant.doctoral, Ph.D., Mechanical Engineering -- University of Idaho - College of Graduate Studies, 2019-0
Behavioral and environmental factors affecting nest site selection and nest survival in a colonial nesting waterbird
No full textWestern grebe (Aechmophorus occidentalis) populations in North America declined by 90% between 1970 and 2017. Western Grebes nest in breeding colonies and traditional nest monitoring methods cause substantial disturbance to the breeding colony. We explored a non-invasive technique to estimate nest survival and to identify the factors that influence nest survival. We used a small unmanned aerial system (drone) to map and monitor the largest grebe colony in Idaho at Cascade Reservoir. We conducted six flights between 20 June – 11 July 2018 and used the photographs from each flight to create an orthomosaic image that we then digitized and georeferenced. We used the orthomosaic images to assess fine-scale habitat selection for 940 nests as well as recreate nest histories and estimated nest fate for 709 grebe nests. We created a resource selection function using use/non-use data to assess nesting habitat preference. Similarly, we used program MARK to model nest survival. We found that Western Grebes preferred to nest in water between 40-80cm and probability of use increased as distance to open water increased. Our nest survival analysis indicated that when extrapolated to a 30-day nesting cycle, our model estimated that nest success was 51.8%. Probability of nest survival was positively correlated with water depth at the nest and the aggregation index, and negatively correlated with distance between the nest and the colony center and distance to deep water habitat. The results of this study can be used to inform conservation efforts by identifying which habitat characteristics Western Grebes are selecting for as well as identifying areas of the colony that are most.masters, M.S., Natural Resources -- University of Idaho - College of Graduate Studies, 2019-1
The Autoregressive Structural Model for Multivariate Longitudinal Data Analysis
No full textAlthough a variety of statistical methods are available for analyzing longitudinal data, modeling the dynamics of a complex structural model remains a difficult methodological challenge. In this thesis, an Autoregressive Structural Model (ASM) was developed to exam- ine the relationships between social activity, physical activity, and functional health status (‘factors’) on depressive symptoms while accounting for temporal dependence. The ASM builds on an autoregressive model for repeated measurements and incorporates a structural equation model that delineates the mechanism among the factors. We applied the ASM to elucidate the impact of these factors on depressive symptoms in the China Health and Retirement Longitudinal Study (CHARLS), a multi-year study of aging involving 20,000 participants 45 years of age and older. The results indicate that social and physical activity independently and consistently mitigated depressive symptoms over the course of five years, by mediating through functional health status.masters, M.S., Statistical Sciences -- University of Idaho - College of Graduate Studies, 2019-1
OXIDATION KINETICS OF GRAPHITE AND COAL USING THERMOGRAVIMETRIC ANALYSIS
No full textThermogravimetric analysis was conducted on two sets of solid fuels to observe trends in combustive behavior. The introduction provides descriptions of the equipment used to conduct experiments and theory for solid reactions. Chapters 2 and 3 are conference papers submitted to The Combustion Institute, and their results were presented at the 2018 Western States Section of the Combustion Institute meeting and the 11th US National Combustion meeting, respectively. The conference paper in Chapter 2 titled Combustion of Graphite Nanoparticles with Copper (II) Oxide in a Thermogravimetric Analyzer with Evolved Gas Analysis describes procedures of and results from experiments performed on the caron/graphite mixture with respect to increasing temperature. While samples were heated from room temperature to 975°C exhaust from the TGA furnace was purged to a NDIR gas analyzer for quantification of CO and CO_2. Modulated TGA experiments were conducted to find activation energy across the range of temperatures, which were compared with gas evolution and thermogravimetric behavior of the samples subjected to increasing temperature at rates of 5, 10, 15, and 20°C/min. Results show early production of CO leads to a rapid production of CO_2 and the evolution of these gasses are related to the weight lost from solid samples. Peak activation energy values follow peaks in the rate of weight loss, and EDS data showed CuO reduced to Cu in a sigmoidal manner as the temperature increased. Chapter 3 is the conference paper titled Modulated Thermogravimetric Experiments on Argonne Premium Coal Samples with Combustion Gas Analysis. The eight coal samples provided by the program were subjected to two types of experimentation; modulated TGA tests, and product analysis using a FTIR spectrometer with air as the oxidizer. The modulated TGA experiments were carried out in the temperature range of 20-750°C. The temperature was increased at a rate of 2°C per minute, each test had a superposed temperature modulation with amplitude ±5°C and a period of 200 seconds. The second set of standard TGA tests were conducted in the same temperature range and for a linear ramp rate of 5°C per minute to 750°C. The furnace was purged using air at a rate of 25 mL per minute. The resulting exhaust from the furnace was directed to a FTIR for identification and quantitation of the products of combustion. Weight loss of the solid products correlated to the rank of each coal sample; however higher ranked coals showed pre-combustive weight gain in the range 200-320°C which has been attributed to chemisorption. Similar to experiments described in chapter 2, peak values for the rate of weight loss are related to CO and CO_2 evolution and activation energy. Additional evolved gasses identified by the FTIR spectrometer were methane and aromatic nitro compounds. Chapter 4 concludes with discussion on CLOU techniques and how they relate to results obtained from chapter 2. In the chapter specific values of temperatures, rates, and percent weight are givend that were omitted from the original papers. The final section purposes further experimentation to enhance the study herein.masters, M.S., Mechanical Engineering -- University of Idaho - College of Graduate Studies, 2019-1
Arithmetic Relations Between Fourier Coefficients of Siegel Paramodular Forms
No full textThis dissertation presents fundamental relations satisfied by the Fourier coefficients of a Siegel paramodular form F: ℋ2→ℂ which is an eigenform for the paramodular Hecke operators at primes which do not divide the level of the Siegel paramodular form. We exhibit relations between coefficients indexed by positive-definite, primitive, integral binary quadratic forms of discriminant d f^2 where d<0 is a fundamental discriminant and f is a positive integer.doctoral, Ph.D., Mathematics -- University of Idaho - College of Graduate Studies, 2019-0
Nematode Defenses: Characterization of the Superoxide Dismutase (SOD) from the Potato Cyst Nematode Globodera pallida
No full textPotato cyst nematodes (PCN), such as Globodera pallida and Globodera rostochiensis, are some of the most agriculturally and economically important pests of potato. If no measures are used to control this pathogen, then it has the potential to cause up to 80% yield loss. Globodera pallida is a sedentary endoparasitic nematode that infects the roots of a susceptible plant in order to establish a feeding site as a sole source of nutrition for its development. Plants are not defenseless when exposed to pathogens and are able to fight off most of them by activating an innate immune system. An oxidative burst, along with the production of the reactive oxygen species (ROS), is an important part of plant defenses. Reactive oxygen species, such as superoxide radical (O2-˙), hydrogen peroxide (H2O2), and hydroxyl radical (OH·) are highly toxic molecules that cause damage to pathogens. In order to successfully infect the plant, nematodes protect themselves from ROS through the activation of antioxidant metabolism and ROS scavenging enzymes. One of these enzymes is a superoxide dismutase (SOD; EC 1.15.1.1), which prevents cellular damage by catalyzing conversion of the superoxide radical (O2-˙) to hydrogen peroxide (H2O2) and molecular oxygen (O2). The main goals of this study were to: 1) isolate and localize the expression of the SOD gene from G. pallida, and 2) study its expression after infection of the susceptible potato cv. Desiree, resistant potato cv. Innovator, and immune host (Solanum sisymbriifolium). We have isolated a putatively secreted isoform of the superoxide dismutase from G. pallida and localized the expression of this gene in the posterior region of the nematode, to the hypodermal tissue. However further analysis is required to determine if this enzyme is being secreted to the surface of the nematode. The SOD gene was significantly upregulated when nematodes infected roots of a host plant, but significant differences in expression during the infection of susceptible, resistant, or immune hosts were not observed. Our study suggests that this gene may be responding to stress regardless of whether the nematode is experiencing a compatible or an incompatible interaction.masters, M.S., Plant, Soil and Entomological Sciences -- University of Idaho - College of Graduate Studies, 2019-1