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Calculations from On the Existence of Periodic Traveling-Wave Solutions to Certain Systems of Nonlinear, Dispersive Wave Equations
No full textIn the field of nonlinear waves, particular interest is given to periodic traveling-wave solutions of nonlinear, dispersive wave equations. This thesis aims to determine the existence of periodic traveling-wave solutions for several systems of water wave equations. These systems are the Schr¨odinger KdV-KdV, Schr¨odinger BBM-BBM, Schr¨odinger KdV-BBM, and Schr¨odinger BBM-KdV systems, and the abcd-system. In particular, it is shown that periodic traveling-wave solutions exist and are explicitly given in terms of cnoidal, the Jacobi elliptic function. Certain solitary-wave solutions are also established as a limiting case of the periodic traveling-wave solutions, that is, as the elliptic modulus approaches one
Environmental Factors Associated With Triploid Aspen Occurrence in Intermountain West Landscapes
Get PDFPolyploidy is common among plants and can contribute to physiological and morphological differences, altering how plants respond to environmental changes, promoting genetic diversification and even species radiation. Quaking aspen (Populus tremuloides), a keystone species associated with high plant and animal diversity is frequently found in mixed diploid/triploid populations in the Intermountain West. Triploid aspen carries an extra chromosomal copy, whereas the diploid type contains two chromosomal copies. High mortality rates and widespread population declines in aspen are of increasing concern in the Intermountain West, and often ascribed to changing climates and drought stress events. The goal of this study was to better understand environmental factors influencing the distribution of triploid aspen population in the Intermountain West. Using restriction-site associated DNA sequencing (RAD-seq), a method used to identify thousands of genetic markers from a group of individuals, we examined the occurrence of diploid and triploid aspen populations at various spatial scales in relation to environmental variables associated with soil moisture content. Our results suggest that triploidy in aspen on the landscape is associated with environmental variables related to soil moisture and may be influenced by specific local variations in topography, climate, and precipitation patterns. Overall, we found that conditions associated with low soil moisture were associated with lower frequencies of triploid aspen. Our results suggest that triploid aspen clones may be more susceptible to mortality than diploid clones in the warmer, drier climates expected with climate change. We acknowledge, however, that there are many knowledge gaps regarding the generation and persistence of triploid aspen clones. Understanding the causes and consequences of triploidy in aspen will be important in predicting and managing aspen persistence in landscapes of the western U. S. under changing climate conditions
Systematic Review of the Use of Multiperson Activity Schedules for Individuals With Disabilities
Get PDFMultiperson activity schedules capitalize on the benefits of independent activity schedules, a commonly used visual support for individuals with disabilities. Activity schedules minimize the need for adult prompting and increase independence with complex tasks by breaking them down into pictures, written words, or videos. Multiperson schedules allow pairs and small groups of individuals with disabilities to work together with minimal adult involvement to accomplish a task. This systematic review aims to inform researchers and other interested persons regarding the use of multiperson activity schedules to aid in decision-making and support implementation. We screened 146 articles and dissertations against our study inclusion criteria and found 11 studies meeting the criteria. Data compiled from the 11 studies highlight the usefulness and effectiveness of this evolving intervention. Strengths and weaknesses of the included studies are discussed, as well as implications for future research and practice
Hunting for Agriculture: Unraveling Ecological Motivations in the Transition to Farming by the Fremont Cultural Complex
Get PDFThis study explored the profound human history shift from foraging to agriculture, focusing on Utah\u27s Fremont cultural complex. Utilizing the Prey-Rank Model, we investigated whether dwindling encounter rates with high-rank prey prompted the Fremont\u27s adoption of agriculture. We quantified past resource trends by analyzing the Utah archaeofaunal database to discern if ecological conditions influenced this transition. If confirmed, it suggests adaptive responses to a decline in high-ranked game led to a more resource-intensive survival strategy. This research provides crucial insights into the motivations behind the Fremont\u27s agricultural adoption, enhancing our understanding of human-environment interactions and adaptations throughout history
Protein Residue Analysis in Archaeology: A Geological Contamination Experiment
Get PDFProtein residue analysis has been used by archaeologists for decades to explore ancient diets and hunting behaviors based on proteins deposited on tools and artifacts, however, protein contamination of buried artifacts has been assumed but lacked formal study. Through a contamination experiment testing different geological contexts (e.g. water movement and freeze-thaw), possible routes of protein contamination within soil were identified, adversely impacting protein residue analysis conducted on buried artifacts. Protein was found to move through soil in large enough concentrations to elicit positive protein residue results on sterile artifacts that never made direct contact with the protein source used in this study. Furthermore, protein movement was identified in the absence of water movement and freeze-thaw conditions. More research and greater sample sizes are needed but the result of this study is compelling enough to provide additional caution when protein residue analysis is used on artifacts from buried contexts
Public Cyberattack Attribution and Domestic Political Considerations: An Analysis of State Decision Making
Get PDFWhen a country is targeted with a cyberattack, what compels its government to publicly attribute the perpetrators of the attack rather than keep their attribution private? Cyberattacks are an increasingly utilized weapon of international conflict by governments, groups, and individuals. Following a cyberattack, the target of the attack may investigate the origin of the attack and may choose to share their findings with the public; alternatively, they may choose not to publicly share their findings.
While we know that forensic capabilities and international political factors contribute to the decision of governments to make public cyberattack attribution, domestic political circumstances may also inform this choice. This study finds a positive association between the odds of public cyberattack attribution among countries with greater degrees of press freedom as well as a decreased odds of public attribution when both the target and the suspected initiator are democracies. Understanding the complexity of government attribution choices will inform international cyber conflict and war perceptions and aid in the anticipation of conflict and war escalation
Across the Snake River Plain: Terminal Pleistocene, Early Holocene, and Early Middle Holocene Land-Use in Southeast Idaho
Get PDFThe range of mobility demonstrated to overcome challenges with resource distribution is a hallmark of hunter-gatherer societies. Previous studies in southeast Idaho have investigated the possibility that precontact human movement was impacted by climatic differences. According to preliminary studies on regional obsidian toolstone conveyance, land use patterns were already changing throughout the early Holocene due to increased aridity. However, the geographical distribution of Northern Side-notched projectile points suggests a significant expansion in mobility at the early Holocene/middle Holocene transition. This thesis tests the hypothesis that precontact early middle Holocene human mobility in the study area was conditioned by environmental factors during this period through the X-ray Fluorescence analysis of 376 volcanic glass projectile points dating to the terminal Pleistocene, early Holocene, and early middle Holocene periods. The results of this study indicate that human mobility was heightened during the early Holocene period rather than the early Middle Holocene period. This research contributes a deeper course-grained understanding of the land use patterns of precontact peoples in the study area
IANOVA: Multi-Sample Means Comparisons for Imprecise Interval Data
Get PDFIn recent years, interval data has become an increasingly popular tool to solve modern data problems. Intervals are now often used for dimensionality reduction, data aggregation, privacy censorship, and quantifying awareness of various uncertainties. Among many statistical methods that are being studied and developed for interval data, the significance test is particularly of importance due to its fundamental value both in theory and practice. The difficulty in developing such tests mainly lies in the fact that the concept of normality does not extend naturally to interval data (due the range of an interval being necessarily non-negative), causing the exact tests to be hard to formulate. In the literature, tests for comparing means of one or two sample interval data have been developed, which motivates the exploration of the multi-sample case. In this thesis, we propose a novel asymptotic (as the sample size goes to infinity) method for comparing multi-sample means with interval data. This procedure builds a test statistic based on a ratio of between-group interval variance and within-group interval variance. The theoretical results for this procedure are derived. Simulation results with both discrete and continuous data validate our procedure, and show promising small sample performances. Finally, we apply our method to ground snow load interval data, where we are able to detect interval mean differences across regions in Canada
Improvement of Oocyte Developmental Competence and Potential Strategies for Non-Invasive Embryo Viability Assessment
No full textAssisted reproductive technologies (ART) have become a valuable tool in the production of animals and also treatment for human infertility. In animal production specifically, somatic cell nuclear transfer (SCNT), or cloning, is important for the production of transgenic or high genetic value animals. Oocyte maturation is a necessary and critical step in the production of embryos and greatly impacts the success of all subsequent ART techniques. While in vitro maturation is a routinely used technique, improvements are needed to enhance the efficiency in producing embryos. There is also a need to develop non-invasive methods to assess the quality of oocytes and embryos and determine their chances to produce a live animal or child. The work within this dissertation is aimed at addressing both of these issues and may be applied to improve animal production and also human infertility.
Many livestock oocytes can be collected from abattoir derived ovaries but must be matured in the lab. Many techniques have been used to improve the number and quality of mature oocytes. Recently, the cytokine (FGF2, LIF and IGF1) supplemented medium termed ”FLI” medium has shown promise using pig oocytes. We aimed to test the effects of these cytokines on cattle oocyte maturation due to the importance cattle have in agriculture. We found that FLI medium improved the quantity and quality of mature oocytes and embryos as well as effected the expression of developmentally important genes. When these embryos were transferred to recipients it also resulted in a significant increase in live animals born.
We also investigated the use of Raman spectroscopy as a non-invasive method to determine the developmental potential of cattle embryos. Raman spectroscopy measures vibration of chemical bonds and can be used to measure metabolites within embryo culture medium. Spent culture medium is a good source of information on embryos and is usually discarded after embryo culture. We found that Raman spectroscopy, along with machine learning, can determine culture medium that contained embryos that developed successfully to the blastocyst stage compared with those that did not.
Cumulus cells, which surround and support the oocyte, are also a good source of information that can be used as a non-invasive method of developmental potential. Cumulus cells also play an important role in oocyte maturation, with signals going from cumulus cells to the oocyte and from oocyte to cumulus cells. We used single-cell RNA sequencing to look at differential gene expression of cumulus cells from oocytes matured in FLI medium compared to control medium. In cumulus cells from the FLI group, we saw differential gene expression in several important cellular pathways and also expression of genes associated with improved developmental potential.
Overall, this work has increased our efficiency in producing cloned cattle. We also have observed differential gene expression in oocytes, embryos and cumulus cells that may be important in oocyte maturation and embryo development
Variations on Leitmotif: Firebird Rises
Get PDFThis thesis begins with an introduction that discusses the various influences on the development of the creative novella portion. These influences include Russia literature and folklore, as well as the genres of alternative history and speculative fiction. The novella takes place in a re-imagining of Moscow, Russia during the 1917 Bolshevik Revolution. The novella portion is driven by a close focus on character, with emphasis on reactions to wartime pressures and interpersonal relationships forming the central conflict