Matching Items (55)
Description
Woody plant encroachment is a worldwide phenomenon linked to water availability in semiarid systems. Nevertheless, the implications of woody plant encroachment on the hydrologic cycle are poorly understood, especially at the catchment scale. This study takes place in a pair of small semiarid rangeland undergoing the encroachment of Prosopis velutina Woot., or velvet mesquite tree. The similarly-sized basins are in close proximity, leading to equivalent meteorological and soil conditions. One basin was treated for mesquite in 1974, while the other represents the encroachment process. A sensor network was installed to measure ecohydrological states and fluxes, including precipitation, runoff, soil moisture and evapotranspiration. Observations from June 1, 2011 through September 30, 2012 are presented to describe the seasonality and spatial variability of ecohydrological conditions during the North American Monsoon (NAM). Runoff observations are linked to historical changes in runoff production in each watershed. Observations indicate that the mesquite-treated basin generates more runoff pulses and greater runoff volume for small rainfall events, while the mesquite-encroached basin generates more runoff volume for large rainfall events. A distributed hydrologic model is applied to both basins to investigate the runoff threshold processes experienced during the NAM. Vegetation in the two basins is classified into grass, mesquite, or bare soil using high-resolution imagery. Model predictions are used to investigate the vegetation controls on soil moisture, evapotranspiration, and runoff generation. The distributed model shows that grass and mesquite sites retain the highest levels of soil moisture. The model also captures the runoff generation differences between the two watersheds that have been observed over the past decade. Generally, grass sites in the mesquite-treated basin have less plant interception and evapotranspiration, leading to higher soil moisture that supports greater runoff for small rainfall events. For large rainfall events, the mesquite-encroached basin produces greater runoff due to its higher fraction of bare soil. The results of this study show that a distributed hydrologic model can be used to explain runoff threshold processes linked to woody plant encroachment at the catchment-scale and provides useful interpretations for rangeland management in semiarid areas.
ContributorsPierini, Nicole A (Author) / Vivoni, Enrique R (Thesis advisor) / Wang, Zhi-Hua (Committee member) / Mays, Larry W. (Committee member) / Arizona State University (Publisher)
Created2013
Description
Website usage on both smartphone and tablet devices is rapidly increasing. Website success hinges largely upon how well information on the site is recalled and perceived. The purpose of this study is to explore the question of whether or not the differences in display size and resolution of smartphone versus tablet devices affect the recall of website information. I hypothesize that tablets will produce greater website recall than smartphones, due to their larger screen size and higher resolution which may reduce cognitive strain. During the study, participants viewed a sample website for two minutes on either an iPhone or iPad, and then participated in a brief 20 question memory test to evaluate how well they remembered the website information. Although test scores for the iPad users were about one test point higher than test scores for the iPhone users, the difference was not statistically significant. However, the study was limited by the low sample size (n = 94). This indicates that further research may find that tablets indeed allow for increased recall of certain kinds of website content.
ContributorsRaines, David Thomas (Author) / Martin, Judith (Thesis director) / Johnson, Kathryn (Committee member) / Wiedmaier, Benjamin (Committee member) / Barrett, The Honors College (Contributor) / Hugh Downs School of Human Communication (Contributor) / Department of Psychology (Contributor)
Created2013-05
Description
Engineered pavements cover a large fraction of cities and offer significant potential for urban heat island mitigation. Though rapidly increasing research efforts have been devoted to the study of pavement materials, thermal interactions between buildings and the ambient environment are mostly neglected. In this study, numerical models featuring a realistic representation of building-environment thermal interactions, were applied to quantify the effect of pavements on the urban thermal environment at multiple scales. It was found that performance of pavements inside the canyon was largely determined by the canyon geometry. In a high-density residential area, modifying pavements had insignificant effect on the wall temperature and building energy consumption. At a regional scale, various pavement types were also found to have a limited cooling effect on land surface temperature and 2-m air temperature for metropolitan Phoenix. In the context of global climate change, the effect of pavement was evaluated in terms of the equivalent CO2 emission. Equivalent CO2 emission offset by reflective pavements in urban canyons was only about 13.9e46.6% of that without building canopies, depending on the canyon geometry. This study revealed the importance of building-environment thermal interactions in determining thermal conditions inside the urban canopy.
ContributorsYang, Jiachuan (Author) / Wang, Zhi-Hua (Author) / Kaloush, Kamil (Author) / Dylla, Heather (Author)
Created2016-08-22
Description
This research project investigated known and novel differential genetic variants and their associated molecular pathways involved in Type II diabetes mellitus for the purpose of improving diagnosis and treatment methods. The goal of this investigation was to 1) identify the genetic variants and SNPs in Type II diabetes to develop a gene regulatory pathway, and 2) utilize this pathway to determine suitable drug therapeutics for prevention and treatment. Using a Gene Set Enrichment Analysis (GSEA), a set of 1000 gene identifiers from a Mayo Clinic database was analyzed to determine the most significant genetic variants related to insulin signaling pathways involved in Type II Diabetes. The following genes were identified: NRAS, KRAS, PIK3CA, PDE3B, TSC1, AKT3, SOS1, NEU1, PRKAA2, AMPK, and ACC. In an extensive literature review and cross-analysis with Kegg and Reactome pathway databases, novel SNPs located on these gene variants were identified and used to determine suitable drug therapeutics for treatment. Overall, understanding how genetic mutations affect target gene function related to Type II Diabetes disease pathology is crucial to the development of effective diagnosis and treatment. This project provides new insight into the molecular basis of the Type II Diabetes, serving to help untangle the regulatory complexity of the disease and aid in the advancement of diagnosis and treatment. Keywords: Type II Diabetes mellitus, Gene Set Enrichment Analysis, genetic variants, KEGG Insulin Pathway, gene-regulatory pathway
ContributorsBucklin, Lindsay (Co-author) / Davis, Vanessa (Co-author) / Holechek, Susan (Thesis director) / Wang, Junwen (Committee member) / Nyarige, Verah (Committee member) / School of Human Evolution & Social Change (Contributor) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
In this honors thesis certain religious and moral beliefs were analyzed and used to predict active euthanasia acceptance for Christians in the United States. The factors used to predict euthanasia acceptance for a suffering, terminally ill individual were religiosity, empathy, God representations, and attitudes toward God. Negative correlations were observed between acceptance of euthanasia and religiosity, empathy, positive attitudes toward God, and a benevolent God representation. Positive correlations were observed between acceptance of euthanasia and negative attitudes toward God, whereas there was no significant correlation between support for euthanasia and an authoritarian God representation. When acceptance of euthanasia was regressed on these independent variables, religiosity was the most significant predictor of acceptance. It was concluded that highly religious Christians may tend to prioritize their religious teachings over their instinctual empathy for a suffering person because prematurely ending a patient’s life interferes with God’s will and reduces his role in worldly affairs.
ContributorsAustin, Richard Vincent (Author) / Johnson, Kathryn (Thesis director) / Cohen, Adam (Committee member) / School of Life Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
This research project investigated known and novel differential genetic variants and their associated molecular pathways involved in Type II diabetes mellitus for the purpose of improving diagnosis and treatment methods. The goal of this investigation was to 1) identify the genetic variants and SNPs in Type II diabetes to develop a gene regulatory pathway, and 2) utilize this pathway to determine suitable drug therapeutics for prevention and treatment. Using a Gene Set Enrichment Analysis (GSEA), a set of 1000 gene identifiers from a Mayo Clinic database was analyzed to determine the most significant genetic variants related to insulin signaling pathways involved in Type II Diabetes. The following genes were identified: NRAS, KRAS, PIK3CA, PDE3B, TSC1, AKT3, SOS1, NEU1, PRKAA2, AMPK, and ACC. In an extensive literature review and cross-analysis with Kegg and Reactome pathway databases, novel SNPs located on these gene variants were identified and used to determine suitable drug therapeutics for treatment. Overall, understanding how genetic mutations affect target gene function related to Type II Diabetes disease pathology is crucial to the development of effective diagnosis and treatment. This project provides new insight into the molecular basis of the Type II Diabetes, serving to help untangle the regulatory complexity of the disease and aid in the advancement of diagnosis and treatment.
ContributorsDavis, Vanessa Brooke (Co-author) / Bucklin, Lindsay (Co-author) / Holechek, Susan (Thesis director) / Wang, Junwen (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Gift-giving economies are economic models that freely give resources rather than barter for them or purchase them from market. Need-based transfers fit into this economic model by freely giving resources on the basis of need, provided the giver can spare the resources. The Maasai are an East African pastoral tribe that practices need-based transfers through a tradition they call osotua. If they have a partner with an established osotua relationship, then they will give any amount of cattle that partner request, provided they can spare the cattle. Cheating each other is unheard of in this tradition, but for this simulation I am introducing cheating into this economic model through feigning need. If a cheater is not in need, they will act like they are in need. If they are in need, then the cheater will request more cattle than what they need to survive. I am testing two different responses to cheating: walking-away and punishing. In the walk-away condition, the victim ends their osotua partnership and establishes a new one. In the punishment condition, a portion of the cheater's stolen cattle is destroyed.
ContributorsDunkelberger, Sophia (Author) / Aktipis, Athena (Thesis director) / Presson, Clark (Committee member) / Johnson, Kathryn (Committee member) / School of Social and Behavioral Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
Perceptions of the self differ between cultures, generally between those cultures in the West and East. Some of the ways that these individuals from these cultures may differ are in their self-construal, their collectivist and individualist tendencies, and how they perceive control in their lives. The current study proposes that some of these differences are influenced by different concepts individuals hold regarding the "soul", or inner self. These concepts may be promoted by the different religious beliefs prominent in different regions. The Soul Perception Index, being developed through this study, measures belief in multiple souls, a universal soul, a single soul, or no soul. It was predicted that a belief in a single soul will correlate with an individual view of the self (individualism, independent self-construal, internal locus of control), and a universal or multi-soul belief will correlate with an interdependent view of the self (collectivism, interdependent self-construal, and external locus of control). We found that these variables did not significantly differ in their relationships with soul belief. However, Indian Hindu participants and Chinese participants seemed to score highly on all self-view variables and all soul perception types indicating that individuals from these cultures may be more predisposed to hold opposing beliefs simultaneously while US Christians are not.
ContributorsNaidu, Esha Svetha (Author) / Cohen, Adam (Thesis director) / Glenberg, Arthur (Committee member) / Johnson, Kathryn (Committee member) / School of Historical, Philosophical and Religious Studies (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
This research examined the influence that Christian and Hindu religious beliefs have on environmentalism; specifically, whether beliefs that one would return to this earth after death (i.e., a belief in reincarnation) and how the world might end may explain more positive attitudes toward the environment. Participants were 533 self-identified Christians and Hindus in the United States and India who completed an online survey assessing religiosity, positive attitudes towards environmentalism, afterlife beliefs, and eschatological beliefs. Christians showed significantly lower ratings of environmentalism compared with Hindus. There were also significant negative differences found based on beliefs about heaven, eschatology beliefs, and increased religiosity in Christians, and significant positive differences found based on reincarnation, eschatology beliefs, and increased religiosity in Hindus. Overall, these results suggest that Christians are less likely to have positive attitudes toward environmentalism compared with Hindus, and that beliefs about the afterlife and the end of the world were significant predictors of environmentalist attitudes.
ContributorsParde, Madeline Morgan (Author) / Cohen, Adam (Thesis director) / Glenberg, Arthur (Committee member) / Johnson, Kathryn (Committee member) / Department of Psychology (Contributor) / Sanford School of Social and Family Dynamics (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
Description
High throughput transcriptome data analysis like Single-cell Ribonucleic Acid sequencing (scRNA-seq) and Circular Ribonucleic Acid (circRNA) data have made significant breakthroughs, especially in cancer genomics. Analysis of transcriptome time series data is core in identifying time point(s) where drastic changes in gene transcription are associated with homeostatic to non-homeostatic cellular transition (tipping points). In Chapter 2 of this dissertation, I present a novel cell-type specific and co-expression-based tipping point detection method to identify target gene (TG) versus transcription factor (TF) pairs whose differential co-expression across time points drive biological changes in different cell types and the time point when these changes are observed. This method was applied to scRNA-seq data sets from a SARS-CoV-2 study (18 time points), a human cerebellum development study (9 time points), and a lung injury study (18 time points). Similarly, leveraging transcriptome data across treatment time points, I developed methodologies to identify treatment-induced and cell-type specific differentially co-expressed pairs (DCEPs). In part one of Chapter 3, I presented a pipeline that used a series of statistical tests to detect DCEPs. This method was applied to scRNA-seq data of patients with non-small cell lung cancer (NSCLC) sequenced across cancer treatment times. However, this pipeline does not account for correlations among multiple single cells from the same sample and correlations among multiple samples from the same patient. In Part 2 of Chapter 3, I presented a solution to this problem using a mixed-effect model. In Chapter 4, I present a summary of my work that focused on the cross-species analysis of circRNA transcriptome time series data. I compared circRNA profiles in neonatal pig and mouse hearts, identified orthologous circRNAs, and discussed regulation mechanisms of cardiomyocyte proliferation and myocardial regeneration conserved between mouse and pig at different time points.
ContributorsNyarige, Verah Mocheche (Author) / Liu, Li (Thesis advisor) / Wang, Junwen (Thesis advisor) / Dinu, Valentin (Committee member) / Arizona State University (Publisher)
Created2022