bluuebunny/crossref_metadata_2025 huggingface dataset:
High performance ultra wide band patch antenna design with minimized optimization parameters
Authors:   , Alnahwi Falih Mahdi Mousa
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] In this work, we propose ultra wide band antennas that have small size and simple shapes. The new designs have comparable or improved performance than those of the already available antennas. The thesis aims can be summarized as follows: 1) First, design and fabricate both monopole and wide slot UWB antennas that have simple and small structures and analyze for performance comparable to those of the more complex designs and/or larger size. This part of the thesis can be achieved by modifying already existing antennas, and then utilize them to achieve the second aim of this work, as discussed below. 2) Propose new generalized ways for band notch generation that are suitable for all UWB antennas. This will result in a significant reduction in the optimization parameters. Finally the optimized design will be fabricated to verify the proposed idea. 3) Design and fabricate a new planar monopole switchable antenna that can switch between Multiband/UWB mode that covers the entire indoor applications and Multiband mode that covers some of the outdoor applications for a versatile antenna performance.
Determinants of international cooperation : reciprocity, opportunity, and cooperative norms
Authors:   , Bowling Jeremy
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] This dissertation examines few of the determinants and effects of international cooperation. There are three broad themes that run throughout this dissertation, which are the ideas of reciprocity, opportunity, and cooperative norms. Reciprocity is a large part of the development of cooperation theory, particularly in the study of the evolution of cooperation. While it is mentioned across international relations scholarship, empirical testing of its existence in international politics is scarce. Opportunity is a ubiquitous concept across social science. The concept is used in this dissertation as a challenge to the notion that cooperation reduces the likelihood of conflict, which pervades the study of international conflict, particularly from those that study conflict from the theory of liberalism. Lastly, an exploratory analysis of cooperative norms is examined. Studying the social construction of cooperative norms is important for the broader study of international cooperation. I find that direct and indirect reciprocity are important indicators of cooperation, cooperation will increase the likelihood and severity of dyadic conflict unless both states are highly cooperative with each other, and domestic political institutions may be important for the development of cooperative norms that extend to the international level. Overall, international relations scholars should reexamine how cooperation in viewed and studied, particularly in relation to conflict.
On the kinetics and mechanisms associated with covalent inactivation of protein tyrosine phosphatase 1b (ptp1b) by dietary phytochemicals and affinity labeling molecules
Authors:   , Lewis Sarah M.
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] Phytochemical are compounds that occur naturally in plants. These compounds are what give many foods their distinct color and flavor. There are five major types of phytochemicals; phenolic compounds, terepenes, betalains, glucosinolates, and organic acids. This work focused on a breakdown product of glucosinolates, isothiocyanates, which are found in Brassica, and are common in most diets. Isothiocyanates have a general structure of R-N=C=S, with an electron deficient carbon that is subject to nucleophilic attack by thiols to produce dithiocarbamates. This work investigated the inactivation of protein tyrosine phosphatase 1B by isothocyanates, and found that this occurs via a covalent, reversible mechanism. Affinity labels were originally used to elucidate the active site of many proteins. More recently however, much attention has been given to the use of an affinity label to covalently label a protein. It is with this technique of covalent attachment to our protein of interest that an exo-affinity labeling molecule was designed. The kinetics, stability, and mechanism of these molecules with protein tyrosine phosphatase 1B are evaluated here.
The (dys)functionality of deceptive affection : using a goals-based approach to understand the process of deceptive affection and its connection to relational health in friends with benefits and other intimate relationships
Authors:   , Trask Sara L.
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] The use of affection in relationships plays an important role in developing and maintaining relationships (Floyd, 2006). However, affectionate communication can also provide substantial risks to individual and relational health when it is misattributed (Floyd and Burgoon, 1999, Floyd and Voloudakis, 1999a). The present dissertation assessed 526 participants to examine the process of deceptive affection, both intensified and deintensified, as a communicative tool used to satisfy goals, and how the use of deceptive affection relates to relational health within three relational contexts: friends with benefits, cross-sex friendships, and romantic relationships. The Deceptive Affection Scale (DAS) was created to assess individuals' use of deceptive affection. Results suggest FWBRs produce more deceptive affection, both intensifying and deintensifying, than cross-sex friendships and romantic relationships. Additionally, different goals predicted the use of intensified and deintensified deceptive affection across relational contexts. Finally, results would suggest that deintensifying affection has minimal influence on relational outcomes, however, intensifying affection is negatively associated with relational health. The current study contributes to the expanding literature on affection, particularly deceptive affection, affection exchange theory, and FWBR literature. Implications for findings, limitations, and areas of future research are addressed.
Statistical analysis of bivariate interval-censored failure time data
Authors:   , Zhou Qingning
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] Interval-censored failure time data arise when the failure time of interest in a survival study is not exactly observed but known only to fall within some interval. One area that often produces such data is medical studies with periodic follow-ups, in which the medical condition of interest such as the onset of a disease is only known to occur between two adjacent examination times. An important special case of intervalcensored data is current status data which arise when each study subject is observed only once and the only information available is whether the failure event of interest has occurred or not by the observation time. The areas that often yield such data include tumorigenicity experiments and cross-sectional studies. Sometimes we refer to current status data as case I interval-censored data, and the general case as case II interval-censored data. The analysis of both case I and case II interval-censored data has recently attracted a great deal of attention and many procedures have been proposed for various issues related to it. However, there are still a number of problems that remain unsolved or lack approaches that are simpler, more efficient and apply to more general situations compared to the existing ones. This is especially the case for multivariate intervalcensored data which arise if there are multiple failure times of interest and all of them suffer intervalcensoring. This dissertation focuses on the statistical analysis for bivariate interval-censored data, including regression analysis, model selection and estimation of the association between failure times.
Predicting success in the first year of residency
Authors:   , Fox Chris Ashley
Published: April 2021

This study is motivated by two research questions 1) What are the independent variables that are associated with performance for first year residents in an Anesthesiology Residency? and 2) What linear combination of factors can predict success (not entering remediation/probation) for the first year of residency? A post-hoc correlational analysis of 3 years of first year resident data was conducted using linear regression to determine any significant predictive relationships. Previous literature has indicated that past test performance is likely to predict future performance and those models of prediction that incorporate both cognitive and non-cognitive attributes tend to be the most successful. Results indicated a strong association between Step 1 scores and minority status for predicting performance on first year examinations with weaker associations for the variables of gestalt and interview scores. Analysis also indicated a strong association between gestalt scores and sex and prediction of whether individuals would end up on remediation or probation within their first year of training."
Structuring asynchronous online discussion groups : the impact of role-supported student facilitation
Authors:   , Huang Yemin
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] The purpose of the current study was to explore the effectiveness of a role-supported, student-facilitation strategy on online discussions from multiple dimensions: participation, interaction, levels of knowledge construction and cognition, as well as the impact of each role. All 13 graduate students who enrolled in a master's-level online course participated in this study. First, an unfacilitated discussion was implemented, followed by three student-facilitated discussions, in which four volunteers were assigned different facilitator roles (Devil?s advocate, Questioner, Information provider, and Summarizer). At the end of the class, 10 out of 13 students completed an online survey about their experience in the student-facilitated online discussions. Transcripts of the four online discussions were collected and analyzed using descriptive statistics, social network analysis, content analysis, sequential analysis, and qualitative analysis. Results indicated that student-facilitated and unfacilitated online discussions were similar in respect to participation, but student-facilitated discussions demonstrated significantly improved interaction patterns and levels of knowledge construction and different levels of cognition. The Devil?s Advocate role had a positive impact and the Summarizer?s role had limited effects on levels of knowledge construction. None of the four roles consistently demonstrated a positive impact on participants? cognitive levels. Responses to the survey showed that the student-facilitation strategy was valuable in both group and individual levels.
Analyzing high-throughput genomics data for cancer studies
Authors:   , Kushwaha Garima
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] NGS data output has increased at a rate that outpaces Moore's law, more than doubling each year since it was invented. Studying such high-throughput data has revealed limitless insight about the genome, transcriptome, and epigenome of many species. In this thesis, I contributed the research community with means to better study of such data along with leveraging a high-throughput biological data to better understand epigenetic regulation of a cell and their disease associations using computational methods. Firstly, I contributed towards building on and improving an existing software tool, PRIMEGENS used to design primers for polymerase chain reaction (PCR) which is one of the most breakthrough and highly used technology in the field of genetics. Apart from contributing towards releasing its new version, PRIMEGENSv2, I designed and made available its web-version PRIMEGENSw3 providing an interactive, easy-to-use and user-friendly online tool for high-throughput primer and probe designed. Next, I leverage the high-through sequencing data profiling genomic methylation, expression of genes and histone modifications. I conducted computational analysis of genome-wide epigenetic modifications that play a key role in cancer development and cellular proliferation. We found evidences showing that hypomethylation changes at regions other than promoter region might also contribute to some significant deleterious effect that can result in malignant transformation or tumor progression and thus have higher biological significance. Also, this study contributes to our understanding about the relationship between methylation of different genic parts including exons and introns from 3' and 5' UTRs, with expression levels in chronic lymphocyte leukemia (CLL) samples. Next, a systems biology approach of independent network construction and preservation of 3'UTR methylation and expression data also revealed expression regulation by hypomethylation of 3'UTRs. Lastly, I validated the presence of widespread hypomethylation regions like 3'UTR, gen body and introns and expression regulation in other cancer types. Hence, I present this study as a new paradigm of looking at genome-wide DNA hypomethylation, in addition to hypermethylation, that can be very helpful to unveil their underlying synergistic mechanism regulating the disease. Overall, this dissertation focuses and present how scalability and specificity of the PCR based enrichment method, combined with the throughput and accuracy of the NGS technology, enable researchers to perform ultra-deep sequencing of regions of interest to better understand areas such as tumorigenesis, population diversity, microbial resistance, and disease susceptibility and thereby advance the scientific fields.
Severe winter storms in Missouri from 1960-2010
Authors:   , Crandall Katie
Published: April 2021

Severe winter storms have cost the state of Missouri significant economic loss from property damage, crop destruction, and loss of livestock. Even worse than the economic loss from these storms are the injuries and deaths to humans that they sometimes cause. A severe winter storm is a storm with six inches or greater snowfall in 48 hours and/or an ice storm with [1/4] inch or greater ice accumulation from the storm. A severe winter storms climatology for Missouri from 1960-2010 was created to better understand the development, frequency, and intensity of severe winter storms in Missouri. From the climatology, it was found that heavy snowfall events were by far the most common severe winter storm type in Missouri with 318 heavy snowfall events. Heavy ice events were the second most common with 66 events. Texas/West Gulf originating mid-latitude cyclones was responsible for the majority of severe winter storms in Missouri followed by Colorado originating mid-latitude cyclones. When looking at El Nino Southern Oscillation (ENSO) variability with heavy snowfall events, there is only a slight variation between the number of heavy snowfall events and the phase of the ENSO cycle they occur in. When all of the heavy snowfall events were averaged together there was only a slight difference in the average number of events per winter season during the negative phase of the Pacific Decadal Oscillation (PDO) (6.2) and the number of events per winter season during the positive phase of the PDO (6.5). When all heavy snowfall events were averaged together there is a 1.4 difference in the average number of events per year during the negative phase of the North Atlantic Oscillation (NAO) (4.6) and the positive phase of the NAO (6). Shelter Mutual Insurance Company provided insurance data from 2000-2010 for 56 severe winter storms in Missouri. Claim payouts for these storms totaled $28,543,020.65. Data from the Missouri Department of Transportation (MoDOT) for automobile accidents on Missouri interstates from 2000-2010 showed that there was the most snowfall related automobile accidents when snowfall was between 0-2.9 inches. The number of automobile accidents decreased with increasing snowfall amounts.
Three essays on the economic value of innovation and quality within the soybean supply chain
Authors:   , Cain Jewelwayne
Published: April 2021

Population growth and rise in personal income worldwide have led to a high rate of increase in global food demand. Efforts by global agricultural supply to meet this demand, however, is threatened by a decreasing number of agriculture workers across the globe and a slowing expansion of agricultural acreage. Crucial to this effort is agricultural innovation that leads to increases in agricultural productivity. One of the most important global agricultural crops is soybeans. So far, innovations in the seed quality of soybean has enabled farmers to meet growing global food and energy demands--particularly on specific nutrient components such as protein and oil--and to mitigate the effects of several stresses facing soybean plants including droughts. However, the farmer's ability to remain competitive and meet demand through innovation still requires further understanding of several areas, three of which are the focus of this dissertation. These areas, each one contained in one chapter, addresses a specific topic while following a general theme: analyzing the economic value of innovation and quality within the soybean supply chain. The first chapter looks at the evolution of soybean drought-tolerance to consider if the impact of innovation is evenly distributed geographically in three U.S. relative soybean maturity zones--divided areas defined by how long soybean crops mature based on environmental factors. Results show that crops planted in all three relative maturity zones are exhibiting increasing tolerance over time only against droughts occurring between August and October. There is evidence, however, that soybeans planted in relative maturity zone 4 exhibited the largest improvement in drought tolerance, while those planted in relative maturity zone 3 exhibited the least. In the second chapter, the values of two important soybean traits--protein and oil content--are estimated and the demand and supply factors that affect these values are also analyzed. The results show significant positive values, suggesting that there is an incentive for U.S. farmers to produce soybeans with higher quantities of protein and oil content. Finally, the third chapter uses data on four soybean exporters to the Philippines--United States, Canada, China, and the rest of the world--to determine whether the downward trend in the U.S. market share is due to differences in the quality of soybeans or due to changes in relative prices. Results show that the Philippine demand for imported soybeans is less responsive to relative price changes and is more determined by quality differences. This strongly indicates that the decline in the U.S. import market share may be due to shifting of preferences of Philippine consumers toward soybean qualities inherent in non-U.S. soybeans.
Molecular dissection of meiotic silencing by unpaired DNA
Authors:   , Decker Logan M.
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] Meiotic silencing by unpaired DNA (MSUD) is a genome surveillance mechanism that uses RNAi to protect against genetic parasites such as retrotransposons and viruses. This is accomplished by scanning the genome for DNA segments not paired with a homologous partner during meiosis and targeting the corresponding messenger RNAs for destruction. MSUD begins when a single-stranded RNA is made from the unpaired region and subsequently converted into small interfering RNA (siRNA), which are used as sequence specific guides for mRNA destruction. To date, nine meiotic silencing genes have been characterized and here we report the identification and characterization of two new candidates that are orthologous to the conserved proteins CBP80 and EPS15.
This way back : essays from Cyprus
Authors:   , Eleftheriou Joanna
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] This Way Back is a creative dissertation that explores the predicament of the transmigrant, the immigrant who has the capability of returning to the host country, and gets caught in an in-between space, not quite assimilated, and not quite unchanged. Transmigrant subjectivities coincide with globalized financial markets, and with twenty-first century forms of national allegiance. The text calls several binaries into question: Greek/Turk, Greek/Cypriot, Greek/American, gay/straight, male/female, ancient/modern, critical/creative writing, and, through its form, essay collection/memoir. The critical introduction, "Essay, Memoir, or Both? Hunger of Memory and the Problem of Nonfiction Hybrids" addresses this binary, and suggests that reading Hunger of Memory as a memoir animated by essayism makes possible a reconciliation of contradictions that have puzzled Rodriguez scholars in the past. The main, creative component of the dissertation relates stories from the author's life as a New-York-born Greek-speaking citizen of Cyprus: dancing to re-enact a mass suicide by jumping off a school stage onto gym mats, harvesting carobs on her great-grandfather's land, purchasing UNESCO-protected lace, traveling against her father's wishes to the island's occupied north, and pruning cypress trees, geraniums, and jasmine after he grew too weak to lift the shears. Narrating these stories allows her to investigate questions of voluntary and forced migration, nationhood, and war. Political events such as the 1959 guerrilla war against British rule, and the 1974 partition of the island, are conveyed through the stories of Cypriot people--the island's refugees and its returnees, among them the author's late father. Together, the essays are a memorial, one which embodies the links between political and personal loss; the individual and the environment; the living and the dead.
Rapid processing of municipal and agricultural waste streams in supercritical water for energy generation and nutrient recovery
Authors:   , Miller Andrew
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] A factorial experiment was designed and conducted to explore the effect of four variables, concentration, pressure, excess oxygen, and inlet temperature, on three responses, exothermic temperature difference, maximum temperature, and NJa. Concentration had an effect on all three metrics, excess oxygen had a negative effect maximum temperature and NJa, and inlet temperature had a positive effect on maximum temperature and a negative effect on NJa. Pressure was found to have a positive impact on NJa. Stoichiometric excess oxygen was found to be a functional replacement for alcohol co-fuels. Cow manure was treated by SCWO for the first time in the literature. Full conversion was achieved and the effluent was applied to plant growth studies showing a statistically significant improvement over the conventional method of land application of manure. A hydrothermal flame was generated in a SCWO reaction system for the first time without the use of an alcohol of fuel gas co-fuel or primary fuel. Construction and commissioning of a SCWO pilot unit was completed and support activities provided additional information to assist in operation of the unit.
Transient collagen triple-helix binding to membrane type 1 matrix metalloproteinase : interaction studies and NMR-guided structural docking
Authors:   , Zhao Yingchu
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] MT1-MMP (MMP-14) as pericellular collagenase is critically involved in cancer cell invasion through collagen barriers that it degrades. To better understand the structural and mechanistic details underlying collagenolytic activity of MMP-14, a solution NMR approach is used here to investigate interactions between individual MMP-14 catalytic and hemopexin domain and a collagen-I-mimicking Triple-Helical Peptide (THP). In this study, backbone chemical shifts were assigned for isolated MMP-14 catalytic and hemopexin domains. The results from gel-filtration chromatography, DLS and NMR combined suggested that MMP-14 hemopexin domain behaves consistently as a monomer in solution. NMR-monitored THP titration led to identification of a distinct patch centered about blade I at the exit side of the hemopexin domain as a potential THP binding exosite. Mutation of residues from this area impairs triple-helical peptidase activity of MMP-14. Saturation transfer difference NMR suggests rotational averaging around the longitudinal axis of the triple-helical peptide. Additionally, intermolecular distances between the hemopexin domain of MMP-14 (HPX-14) and THP were measured by paramagnetic NMR using TOAC-labeled THP. Structural models of HPX-14/THP calculated based on PRE-measured distance restraints revealed extensive interaction between MMP-14 hemopexin domain and sequences surrounding the cleavage site in the THP, indicating a distinctive arrangement of the catalytic domain and unique collagen binding conformation of MMP-14 during collagenolysis.
The scaffold protein POSH regulates T lymphocyte function
Authors:   , Cunningham Cody A.
Published: April 2021

T lymphocytes are critical mediators of the adaptive immune response. T cell receptor (TCR) mediated cJUN NH2-terminal kinase (JNK) activation is required for mounting proper T cell mediated immune responses. However, little is know as to how JNK activation is coupled to the TCR. This dissertation shows that the scaffold protein Plenty of SH3s (POSH) is required for optimal JNK activation and effector function in both CD4+ and CD8+ T cells. Additionally, this work shows that POSH is dispensable for JNK activation and positive and negative selection in developing thymocytes. Thus, POSH couples the TCR to JNK activation in a cell type and developmental stage dependent manner. This work also revels a novel target for the treatment of autoimmune disorders such as Type I Diabetes and Multiple Sclerosis.
Images of community crime in Ferguson, Missouri : older adults perspectives prior to July 2014
Authors:   , Fisher-McLean Kandace Lenae
Published: April 2021

Environmental demands such as crime and fear of crime can affect how older adults perceive their individual quality of life in the community. The purpose of this research study was to investigate how older adults perceive crime in Ferguson, Missouri and how their quality of life is affected. Data collection for this research began in October 2013 and concluded in June 2014. This research study offers perspectives of crime in Ferguson, Missouri prior to the events of August 2014 that resulted in the death of Michael Brown and initiation of community turmoil. This qualitative, transcendental phenomenological research study investigated 15 older adults' perceptions of crime in Ferguson, Missouri through auto-photography and photo-elicitation. The results of this research study indicate that concerns with crime in the form of neighborhood disorder do exist. However, for the most part, older adults did not feel that their personal safety was compromised. The presence of lower level neighborhood disorder has created some anxiety about whether signs of physical and social deterioration suggest the onset of future significant decay in the community. These older adults attachment to place combined with their social and physical investment in the community seem to counter the fear of crime they could experience from the presence of neighborhood disorder. Thus, their quality of life has not been gravely affected.
Frames and applications : distribution of frame coeficients, integer frames and phase retrieval
Authors:   , Woodland Lindsey M.
Published: April 2021

The present dissertation is divided into two main areas: frame theoretic results and applications of frames. In particular, the beginning half develops the first detailed theory of the distribution of frame coefficients. Next, the first systematic study of integer frames is included. The latter half of the dissertation is concerned with the application of frames to the area of signal reconstruction. In particular, phase retrieval by subspaces components and norm retrieval are discussed.
â€œSo many foolish virginsâ€: nuns and anti-Catholicism from Maria Monk to the Know-Nothings
Authors:   , Yacovazzi Cassandra L.
Published: April 2021

This dissertation examines opposition to nuns and convent life in America as it was expressed through vigilante violence, propaganda literature, and party politics. While nuns may seem like an unlikely target of hostility, a vast cohort of Americans singled them out as a serious threat to the republic. Between 1830 and 1860 anti-convent propaganda, including Awful Disclosures of the Hotel Dieu by â€œescaped nunâ€ Maria Monk, flooded the literary market. Monkâ€™s work warned of a Catholic conspiracy in the United States through the cloister, depicted alleged horrors of convent life, and cast nuns variously as masculine tyrants, foolish slaves, and whores. Investigators quickly unveiled Maria Monk as an impostor, but her book became the second best-seller after Uncle Tomâ€™s Cabin before the Civil War, and it has never gone out of print. In order to â€œprotectâ€ American women from the nunâ€™s life, mobs stormed convents from Massachusetts to Maryland. By the 1850s, suspicion of nuns became formally politicized by Know-Nothing legislators who established â€œNunnery Committeesâ€ for convent investigations. Although the Civil War quieted the outcry against nuns for a time, the campaign against convents had far-reaching implications. Members of the second Ku Klux Klan relied on anti-convent propaganda to buttress their positions, and common stereotypes of nunsâ€"first evident in nineteenth-century convent narrativesâ€"have also persisted in popular culture. This dissertation argues that the campaign against nuns and convent life was a much greater part of nineteenth-century American popular culture and politics than previous historians have recognized.
Phylogenetic and morphometric analyses of Eastern fluted-point forms
Authors:   , Boulanger Matthew T.
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] This dissertation constitutes two mutually complementary approaches to the study of Paleoindian material culture in eastern North America, ca. 13,500-10,500 calendar years before present. Archaeologists have long held that the East contains a substantially greater degree of morphological variation in Paleoindian point forms, though precisely why this is the case has rarely been explained. It is also unclear how many of the various point forms relate to each other in an evolutionary sense--which forms are derived from which, and why? Morphological analyses are conducted on a large sample of intact Paleoindian projectile points from across the East. I use paradigmatic classification to establish classes for use in a cladistic analysis to evaluate heritable continuity within the sample. Results of this analysis suggest that shape and form of Paleoindian projectile points changed in a more-or-less stochastic fashion across space, and evidence for strong selective pressure is limited. Findings concerning the process of character-state change suggest that some characters become fixed early in the evolution of points, whereas others appear to change frequently. The results of this study demonstrate that changes in Paleoindian projectile points can be explained within a cultural-evolution framework.
Call timing interactions, aggressive behavior, and the role of acoustic cues in chorus formation in treefrogs
Authors:   , MartiÌnez-Rivera Carlos C.
Published: April 2021

I studied calling patterns and aggressive behavior of the Bird voiced treefrog, , to assess how dynamic call characters influences males and the factors influencing the onset of choruses and settling patterns of males in a chorus. Choruses are dynamic, socially complex communication networks that function as focal points for sexual selection. Frogs calling in groups produced longer calls, overlapped calls, and engaged in aggressive calling and fights. During call overlap, males increased duration of the silent interval between pulses so that these interdigitated. Males resort to aggression during the early hours of chorus formation, before females arrival, and engage in fights without showing signs they evaluate the opponent's ability. Females preferred long, nonoverlapped calls to overlapped calls and overlapped calls with pulse interdigitatio. Females do not respond to aggressive calls alone, but approached combinations of advertisement and aggressive calls. I also studied the role of acoustic signals on chorus formation and location and found that males may benefit from settling next to attractive males and that calls influences the behavior of males by attracting individuals to the established chorusing area, and to new areas within the breeding area in some species.
Weak Hardy spaces and paraproducts
Authors:   , He Danqing
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] The purpose of this dissertation is to provide a new square function characterization of weak Hardy spaces in the full range of exponents possible and use this characterization in applications on endpoint estimates for multilinear paraproducts. Additionally, we prove several maximal characterizations of weak Hardy spaces and obtain several properties of these spaces. Our main result is a Littlewood-Paley square function characterization of the Hardy spaces. Our proof is based on a Calderon-Zygmund type decomposition of distributions in Hardy spaces and on interpolation. Our results allow us to obtain endpoint estimates for several operators in terms of square function characterizations of weak L^p norms. As an application of this technique, we prove endpoint boundedness for mutlilinear paraproducts.
A space for the public : positioning the online commenter in the field of professional journalism
Authors:   , Wolfgang J. David
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Online commenters play an increasing role in online journalism, adding content and commentary, but their role as participants in journalism is in flux as some professionals diminish the commenter role and push to delegitimize their content. This textual analysis and ethnography considers the state of the relationship between the journalist and the commenter in the journalism field broadly, as well as at one news organization. The analysis relies on boundary work, field theory, and gatekeeping in understanding how the commenter and journalist negotiate appropriate roles for one another. The textual analysis included 77 articles published about online commenting over a three-year period and the ethnographic analysis included studying one news organization by spending 90 hours in the newsroom, conducting 16 interviews, and collecting more than 8,000 comments for analysis. This study found that journalists negotiate the boundaries of the field to keep the commenter at a distance, perceive the commenter as a force for the transformation of the professional field, and adopt practices to keep the commenter from influencing professional content and the credibility of the organization. These findings suggest that journalists have used negative perceptions of online commenters to publicly shame the worst actors and institute new inhibitive practices in response, rather than seeing the commenter as a potential collaborator to professional journalism.
A descriptive analysis of teachers' use of evidence-based practices across ethnicity, gender, and disabiltiy risk
Authors:   , Green Ambra Lashar
Published: April 2021

The purpose of this study was to determine to what extent teachers use evidence-based practices during classroom instruction and if those practices were applied differentially across demographic groups (i.e., ethnicity, gender, and disability risk) in Title 1 schools located within the city limits of a large urban center. A descriptive analysis was used to answer the research questions. Results of the study provide evidence that teachers use evidence-based practices at rates lower than advocated in the literature. Additionally, results demonstrated that when teachers did use evidence-based practices they were distributed inequitably across demographic groups. Findings from the study support the need to research parsimonious strategies to increase teachers' equitable use of evidence-based practices.
Mechanisms of cooperation between antigenic and cytokine signals in CD8 T cell activation
Authors:   , Goplen Nicholas P.
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] Our adaptive immune system is comprised of white-blood cells that distinguish self- (our own) from foreignproteins (DNA products) and are capable of establishing long-lived immunity against harmful microbes and cancer. One of the cellular subsets that mediate cellular immunity, or protection by distinction, called CD8 T cells, specifically kill only virally infected or cancerous cells. In order to do so, CD8 T cells must integrate signals from the environment that include sensing both small pieces of proteins presented by other immune cells and proteins produced by the inflammatory, or "early-warning", anti-microbial immune response. It is not clear how these two signals (antigen and inflammatory proteins) integrate to activate the cell-mediated immune response that leads to direct killing of infected cells. Answers to how these signals cooperate to activate the immune system, could provide insight into new therapies for caner, autoimmune diseases, and vaccinations. Here, we find specific conditions that lead to activation of CD8 T cells potentially able to respond to self-antigens important for auto-immunity and cancer. Specifically we found that the strength of signal through the receptor that recognizes small pieces of protein, influenced the T cell's ability to sense inflammatory proteins. Further, we found that signals from the inflammatory environment utilize the cell-membrane receptor used to sense small pieces of proteins from self or foreign sources. In an unexpected way response to inflammatory proteins required CD8 T cells to recognize, or sense, self-antigens.
Call synchrony and the evolutionary origins of leader preference in Neoconocephalus ensiger katydids
Authors:   , Murphy Megan
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Many species of acoustically communicating insects and anurans display a female preference for males producing their calls just ahead of those of their neighbors. The evolutionary origin of these preferences is unclear. We test whether leader preference is adaptive in Neoconocephalus katydids. The ability to produce leading calls was not correlated with male quality in a species with leader preference or two closely related species without the preference. However, in N. ensiger, the species with the preference, females mating with leaders produced higher quality offspring than those mating with followers. This suggested that leader preference is adaptive and selected for in this species. The ability to produce leading calls was not heritable, meaning that the preference cannot have an evolutionary effect on the male trait and they will not become coupled. Male N. ensiger adjust the timing of their chirps relative to their neighbors, which leads to synchrony within a chorus. The mechanism used by N. ensiger males differs from that of all previously described species with acoustic synchrony. Neoconocephalus ensiger males adjust their actual intrinsic chirp rate to match that of other males. The characteristics that determine a male's ability to produce leading calls and the specific source of the female fitness benefit are yet unknown.
Hyperproliferation and altered WNT signaling in the Cystic fibrosis mouse intestine.
Authors:   , Strubberg Ashlee Marion
Published: April 2021

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] Cystic fibrosis (CF) is caused by mutations in the cystic fibrosis membrane conductance regulator (CFTR), a Cl- and HCO3 - channel expressed in several epithelial tissues. CF gastrointestinal (GI) disease presents several life-long complications including dybiosis, low-grade bowel inflammation and an increased risk for GI cancers. The Cftr knock-out (KO) mouse model recapitulates CF intestinal disease including hyperproliferation and the formation of intestinal polyps. Isolated intestinal epithelial cultures (enteroids) demonstrate that hyperproliferation of the Cftr KO epithelium is intrinsic to the CF epithelium as it persists in enteroid culture. Cftr KO enteroids also sustain an alkaline intracellular pH (pHi) which has been shown to stabilize the binding of the Wnt signaling mediator Disheveled (Dvl) at the plasma membrane. Cftr KO enteroids display an increase in Dvl localization and pHi at the apical membrane in crypt cells that correlates with activation of both canonical and non-canonical Wnt signaling. This study indicates a potential mechanism that increased Wnt signaling through Dvl may be a consequence of dysregulated pHi in the Cftr KO intestinal epithelium and contribute to increased proliferation and cell migration.
Molecular mechanisms of stress tolerance in plants
Authors:   , Espinoza Catherine G.
Published: April 2021

Environmental stress conditions such as drought, salt stress and pathogenic fungi affect negatively plant growth and productivity. Therefore, it is necessary to search for new genetic components and strategies for improving resistance and tolerance in crops. In the present thesis, we describe two different approaches that increase our understanding of mechanisms of stress tolerance in plants. The first approach is to study an extreme adaptation to dehydration tolerance from a plant than can "resurrect" after being completely dried. The second study addresses how plant might respond to two different stresses simultaneously, and how one stress can enhance the response to the other. In Chapter 2, we investigate the dehydration tolerance mechanism in the model resurrection grass species Sporobolus stapfianus using a large scale expression profiling of leaf tissues at full hydration, during drying and after re-watering. This study provides some important insights into the gene regulatory mechanisms used by this interesting plant during severe vegetative desiccation and subsequent recovering during re-watering. We also found some genes that are differentially expressed between S. stapfianus and its desiccation sensitive sister species S. pyramidalis. These genes are considered potential candidates for engineering drought tolerant crops. Previous studies have shown a positive effect of chitin (released from the fungal cell wall) on salinity tolerance. In Chapter 3, we explore the cross talk between salt stress and chitin-triggered immune responses. Our results demonstrate a physiological and biochemical link between salinity stress and chitin-triggered innate immunity. Chitin receptors, CERK1 and LYK4, and ANN1, a NaCl- induced calcium permeable channel, interact physically at the plasma membrane and are necessary to modulate early responses (e.g. Ca2+ signaling) to both stresses. Understanding these layers of cross-talk may lead to more sustainable methods to employ innate immunity to protect against both biotic and abiotic stress induced crop losses.
The use of surgical safety checklists during time-outs in rural and urban operating rooms
Authors:   , Lyons Vanessa
Published: April 2021

Operating rooms continue to be one of the most common locations for errors despite interventions aimed at reducing errors. Surgical safety checklists were introduced by the World Health Organization as a tool to improve patient safety. Operating room safety impacts both urban and rural operating rooms, and little research has been completed examining surgical safety in rural operating rooms. This study examined the use of checklists in surgery and compared the use of checklists in rural and urban operating rooms through a survey of operating room nurses. Seventy-seven rural and forty-seven urban nurses completed the survey. Time-outs were completed by almost all subjects but compliance was lower for verbal confirmation of agreement from team members and for the cessation of all other activities. Rural and urban respondents report using a checklist during the time-out. Checklist items most often included in the time-out include the patient's name, consent, site marking, and antibiotic administration. Checklist content were less likely to include team names, anticipated case duration, and surgeon's anticipated critical or non-routine steps. Urban nurses were significantly more likely to verify sterilization indicators. Barriers identified by urban subjects were checklist fatigue, anesthesia and surgeon resistance. Barriers reported by rural subjects were a lack of upper management support, lack of education, lack of monitoring, and practice variances between surgeons and organizations. This research shows that while checklist use has been adopted in many organizations, its use is lacking consistency across both settings and there is a need to understand variation in practice in order to develop effective strategies to improve utilization.
The role of the age-dependent loss of alpha(E)-catenin in increased acute kidney injury
Authors:   , Wang Xinhui
Published: April 2021

The aging kidney undergoes structural and functional alterations which make it more susceptible to acute kidney injury (AKI). Previous studies in our laboratory have shown that the aging kidney has a marked loss of alpha(E)-catenin in proximal tubular epithelium. alpha-Catenin, a key regulator of actin cytoskeleton, interacts with a variety of actin-binding proteins. Fascin 2 is an actin bundling protein that interacts with adhesion molecules and F-actin. In this work, we hypothesized that loss of alpha(E)-catenin leads to disruption of actin cytoskeleton which increases cisplatin-induced injury in aged kidney. A stable shRNA knock-down of alpha(E)-catenin was generated in NRK-52E cells (C2 cells); NT3 cells are the non-targeted control. We demonstrated that age-dependent loss of alpah(E)-catenin in renal tubule epithelial cells facilitates the Fas-mediated apoptotic signaling pathway in response to cisplatin-induced AKI injury. In addition, a cisplatin-induced loss of fascin 2 was observed in aged kidney. Overexpression of Fscn2 abolished increased cisplatin-induced apoptosis, mitochondrial dysfunction and oxidative stress in C2 cells compared with NT3 cells. In conclusion, this dissertation projects novel insight into understanding the increased incidence of AKI in aged kidney and identified a novel role of fascin 2 in renal epithelial cells, which depends on the functional interaction with alpha(E)-catenin and F-actin. These findings may lay the groundwork for new therapeutic approaches to AKI in aged patients in the future.