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The relationships between role ambiguity, managerial coaching, and the QSEN competencies among medical-surgical nurses
Full text linkGuided by the ethical principle of non-maleficence, nurses are called upon to demonstrate increased quality and safety competencies in the midst a highly complex healthcare environment characterized by alarmingly high rates of preventable error. To address quality and safety concerns, the Quality and Safety Education for Nurses (QSEN) faculty adapted the Institute of Medicine’s safety competencies to be nurse specific. These competencies have been included in accredited nursing school curricula with recommendations to include the QSEN competencies in clinical nurse job descriptions and evaluation strategies. Inadequate quality and patient safety often occurs due to healthcare being a highly complex environment with rapid change. Therefore, nurses are at risk to experience role ambiguity which is related to employee disengagement, exhaustion, and increased turnover. The unfavorable consequences of role ambiguity further threaten the nursing workforce. To mitigate the consequences or experience of role ambiguity and to increase nurses’ QSEN competency, nurse leaders are positioned to influence nurses and the work environment to promote improvement of the safety and quality of nursing care. Experts including The Joint Commission look to leaders to promote clinical quality and safety, yet there is concern that an insufficient amount of managerial coaching is being provided to meet the demands of healthcare organizations. To date, medical-surgical nurses’ perceptions of role ambiguity, managerial coaching, and the QSEN competencies had not been studied. Therefore, the purposes of this study were to: (1) examine to what degree do clinical nurses experience role ambiguity; (2) examine to what degree clinical nurses perceive they receive managerial coaching; (3) examine the importance that medical-surgical nurses attribute to quality and safety work (QSEN competencies) as well as their ability to perform the competencies in their clinical nursing roles and (4) examine the relationships among role ambiguity, managerial coaching, QSEN competency, and the sociodemographic characteristics of the medical surgical clinical nurses in this study. For this descriptive, correlational study, participants were recruited from the Academy of Medical Surgical Nurses (AMSN). Data from 267 participants were analyzed using descriptive and inferential statistics. Findings demonstrated that nurses perceive minimal amounts of role ambiguity but reported that they seldom received managerial coaching. Nurses reported that they are somewhat prepared to perform the QSEN competencies, but also rate the importance of the competencies higher than their ability to perform them. There were significant relationships between medical-surgical nurses’ perceived role ambiguity, managerial coaching, and QSEN competencies. Based on these findings, recommendations for education, practice, policy, and future research are discussed.Nursin
Field study of thermally-induced soil-structure interactions in semi-integral bridge structures
Full text linkSemi-integral bridges are considered a promising alternative to conventional bridge designs because they eliminate the need for deck expansion joints. The elimination of expansion joints has been shown to significantly reduce bridge maintenance cost, which can lead to significant savings over the service life of the bridge. These potential savings have led to the increasing utilization of jointless bridge construction with many transportation agencies. However, the elimination of expansion joints is known to lead to secondary problems such as soil-structure interaction between the bridge structure and the abutment backfill due to daily thermal expansion/contraction of the bridge which is not well understood. In this dissertation, the data collected from monitoring of two pilot semi-integral bridges in Texas, USA are presented and evaluated. In this study, the effect of daily and seasonal temperature changes on the displacement of various bridge components, changes in abutment earth pressure, foundation interaction, ratcheting, backfill settlement, etc. have been successfully captured. Among the findings are increased backfill lateral earth pressure due to ratcheting, continuous settlement of the backfill, loss of vertical support for the approach slabs, asymmetric expansion/contraction of the bridge and slight displacement of the bridge superstructure towards one end of the bridge. In addition, it was found that the thermal expansion/contraction of the bridge deck results in cyclic latera loading of the abutment caps and the bridge foundations, despite a lack of rigid connection between the foundations and the superstructure. The cyclic loading of the foundations was also found to cause accumulation of plastic strains in the foundation soil. The causes of the undesired behaviors are identified through successful monitoring of the two semi-integral bridge structures and recommendations are made to minimize the occurrence of such issues in future semi-integral bridge constructions.Civil, Architectural, and Environmental Engineerin
Spacecraft navigation and decision making in uncertain environments
Full text linkAdvancements in the fields of spacecraft navigation and autonomy are needed to ensure future vehicles can complete their missions safely and efficiently. This dissertation proposes several advancements in this domain. First, a process is outlined for mapping an unknown environment using only monocular camera images. It is proposed that the Modified-Half-Normal distribution
can represent map uncertainty more faithfully than the usual Gaussian. The usefulness of this uncertainty model is demonstrated with synthetic images from a spacecraft proximity operations scenario. Second, a variable-resolution system for efficiently mapping terrain and selecting landing sites is developed. This system is proven with flight-test data from a rocket-powered vehicle. Finally, a new Kalman filter is derived for spacecraft with redundant three-axis gyroscopes. The filter fuses all gyroscope measurements and provides a natural method for detecting and isolating faulty gyroscope axes.Aerospace Engineerin
Post-translational and epigenetic regulation in ethylene signaling pathway in Arabidopsis
Full text linkEthylene is an essential plant hormone that plays pleiotropic roles in plant growth, development, and stress response by controlling downstream gene transcription, protein translation, post-translational modifications, and epigenetic modifications. To further understand how ethylene signal is transduced and exerts functional output in regulating plant growth and stress response, my dissertation focuses on the elevation of histone acetylation on ethylene dependent transcriptional activation, phosphorylation regulated ethylene mediated root inhibition, and the participation of ethylene signaling in high ambient temperature response. We found that phosphorylation status of Bβ of PP2A regulates the activity of PP2A. In the absence of ethylene, phosphorylated Bβ inactivates PP2A by destabilizing the interaction between A2-C4-Bβ protein complex. Upon the ethylene treatment, the dephosphorylated Bβ facilitates A2-C4-Bβ protein complex formation to activate PP2A, resulting in the dephosphorylation of EIR1 to promote auxin transport in epidermis of elongation zone, leading to root growth inhibition. Given the increased histone acetylation upon ethylene exposure, we investigated the potential involvement of nuclear acetyl CoA biosynthesis which provides the substrate to acetylate histone in ethylene response. Here we report that ethylene triggers translocation of the pyruvate dehydrogenase complex (PDC) from the mitochondria to the nucleus to synthesize nuclear acetyl CoA to regulate ethylene response. PDC is identified as an EIN2-C nuclear interacting protein and mutations in PDC result in ethylene-hyposensitivity, the reduction of histone acetylation, and the attenuated transcription activation. Nuclear PDC is enzymatically active to synthesize nuclear acetyl CoA for EIN2-C-directed histone acetylation and transcription regulation. These findings uncover the participation of nuclear acetyl CoA synthesis in epigenetic and transcriptional regulation for plant hormone response. Ethylene modulates numerous stress responses to optimize plant adaptation and survival. Herein we show that ethylene signaling pathway is activated upon exposure to high ambient temperatures and is necessary for thermomorphogenesis. Genes involved in ethylene-dependent transcriptional regulation in response to high ambient temperature have specific histone marks, suggesting the importance of rapid regulation and fine-tuning of gene transcription through epigenetic modification changes. Overall, my dissertation highlights the complex molecular mechanisms by which ethylene modulates various aspects of plant biology in response to internal and external stimuli.Plant Biolog
After the coup : mental health, affective lives, and care in Cairo in the aftermath of an unfinished revolution
Full text linkThis project describes how therapy, self-help and general mental health discourse emerged as a response to the mood that emerged in Cairo following the revolution in 2011 and the coup in 2013. It maps the collective affect over the span of a decade through interviews, ethnographic fieldwork and examination of cultural artifacts such as films, novels, and social media posts and show how these events left affective traces— in the form of emotional heaviness, persistent worry and anxiety— in the intimate lives of many Cairenes. In this atmosphere, many turned to therapy and self-help practices as a way to understand and metabolize these affective responses in the ruins of the revolutionary dream. They did not disengage from politics. Rather, they redirected their efforts toward changing the self and their immediate environment. Women were the main actors who carried this out because they — both across generations and social classes— have performed the crucial function of caregivers. Many women now continue this role but in novel ways such as through seeking therapy for themselves while simultaneously supporting their families, friends, and communities. By carrying out this important work they are attempting to sustain social cohesion.Anthropolog
Ammonia acts via TGFβ to induce senescence and DNA damage in neurons contributing to the pathogenesis of hepatic encephalopathy
Full text linkHepatic Encephalopathy(HE) is the onset of psychiatric deficits resultant from chronic liver disease. The pathogenesis of HE remains unknown, but experts believe HE is multifactorial with an observed neuronal dysfunction, without apoptosis, and an upregulation of TGFβ. Hyperammonemia, a known factor of HE, has been linked to senescence in astrocytes, but research on neurons is limited. Senescence, a TGFβ-mediated pathway, is defined as the cease in mitotic activity that results in cellular dysfunction and is associated with the release of senescence-associated secretory phenotype(SASP) factors promoting inflammation. In other neurological diseases, there have been links between aberrant DNA damage response(DDR) mechanisms, and senescence in the brain. The aim of this study is to determine if hyperammonemia alone influences the TGFβ-mediated senescence pathway and DNA damage in neurons leading to the pathogenesis of HE. Sprague Dawley rats were fed a hyperammonemic diet for 6wks and behavioral data, tissues and serum were collected. In vitro, a hippocampal neuronal cell line was treated with various concentrations of NH₄Cl and the ATM inhibitor KU55933. Serum chemistry and liver morphologies were obtained and various DDR, senescence, and SASP markers were assessed via immunofluorescence, qPCR, and ELISA for both in vivo and in vitro experiments. In vivo treatment with hyperammonemia demonstrated no significant differences in liver morphologies, but rather a difference in cognition between the control and treatment groups. There was a significant increase in the expression of DDR, senescence and SASP markers in the hippocampus of the ammonia fed rats. In vitro experiments displayed a significant increase in the same markers, but when treated with KU55933 there was an attenuation in the elevated senescence and SASP markers. Taken together, these data suggest that hyperammonemia alone does initiate the TGFβ-mediated senescence pathway ultimately leading to the development of a functional senescence and release of SASPs in neurons. Hyperammonemia also initiated the DDR and by blocking the DDR, attenuation of the development of senescence and SASP release occurs. These data provide evidence that hyperammonemia-induced neuronal DNA damage and senescence are involved in the pathogenesis of HE and that blocking the DDR could lead to potential therapeutic options.Pharmaceutical Science
Examining equity of access and participation in computer science education
Full text linkComputer science education in K-12 schools is rapidly expanding in the United States. This quantitative research explores student- and school-level factors related to equity of access to and participation in computer science coursework in Texas, examining this issue through a lens of structural and systemic forces. Three analytic chapters contain research related to specific topics within computer science education. The first analytic chapter examines access at the school level and investigates what types of middle and high schools offer computer science courses; the second analytic chapter focuses on participation of computer science in middle school; and the third analytic chapter investigates participation in and perseverance through computer science courses at the high school level.Science, Technology, Engineering, and Mathematics Educatio
A phylogenomics and population genomics study of the robust capuchin monkey (Sapajus) radiation : first genus-wide analyses of admixture and species boundaries in neotropical primates
Full text linkRobust capuchin monkeys, Sapajus genus, are among the most phenotypically diverse and widespread groups of primates in South America, with one of the most confusing and often shifting taxonomies. Indeed, taxonomists and phylogeneticists have suggested multiple taxonomic arrangements for Sapajus, with recent genetic studies suggesting that potentially widespread admixture may have complicated species delimitation. The main goals of this dissertation were to assess the evolutionary history of the robust capuchins and to characterize patterns of admixture across the Sapajus radiation. In this study, I used a ddRADseq approach to generate genome-wide SNP markers for 230 individuals from all putative species of Sapajus collected from 79 localities in Brazil. I then conducted both phylogenomic and population genomic studies of the genus. Using maximum likelihood methods, multispecies coalescent phylogenetic inference, and a Bayes Factor method to test for alternative hypotheses of species delimitation, I inferred the phylogenetic history of the Sapajus radiation and evaluated how many discrete species should be considered within the genus. Using Bayesian and multivariate clustering analyses, I also conducted a hierarchical population genomics study to assess the existence of admixture throughout the Sapajus radiation and across three natural and one human-induced contact zones among pairs of putative robust capuchin monkey species in different regions of Brazil. I found support for recognizing three lineages of robust capuchin monkeys from the Atlantic Forest region lying to the south of the São Francisco river and for the existence off three reciprocally monophyletic clades among the robust capuchins from the Pantanal and Amazon biomes. Different analyses suggested different topologies for Sapajus occurring in the Cerrado, Caatinga, and Northeastern Atlantic Forest. Overall, I found evidence for seven geographically structured genetic clusters within the Sapajus radiation, a result highly coincident with the clades recovered in my phylogenomic reconstructions. Importantly, these results confirm the existence of core geographic regions containing no admixed individuals, despite the evidence of widespread admixture in contact zones throughout Brazil. I also characterized the contact zone across two pairs of species. Finally, I discuss the implications of both my phylogenomic and population genomic studies for Sapajus species recognition and conservation.Anthropolog
An evaluation of the long-term effects of the COVID-19 pandemic on public transit use
Full text linkPublic transit offers significant societal benefits, offering efficient accessibility for all and helping to reduce congestion and greenhouse gas emissions. However, the COVID-19 pandemic has altered many aspects of travel behavior and had particularly important implications for the future use of transit. Despite significant evidence of rebounds in ridership from pandemic lows, transit has not fully recovered. Various factors have contributed to this slow recovery, including continued fears of safety, service cuts, new travel habits, evolving work arrangements, and the growth of online activity participation. In this thesis, we examine changes in public transit use during the pandemic, as well as the potential transitory nature of these shifts. Using data from the 2022 National Household Travel Survey, we explore the permanence of pandemic-era changes to public transportation (PT) use behaviors, connecting future use intentions directly with the change in use during the pandemic. The results of this study point to significant changes of use through the pandemic and heterogeneity in the permanence of these impacts based on age, gender, race, ethnicity, income, and vehicle constraints. By identifying groups who have reduced their use of transit post-pandemic and state that this change is likely to be temporary, we identify individual groups who may be most receptive to PT service improvement interventions. More broadly, we formulate several specific policy recommendations intended to help revitalize transit services in the aftermath of the pandemic and discuss the implications of the pandemic for current and future public transportation policies.Civil, Architectural, and Environmental Engineerin
Impact of climate change on the thermal comfort of single-family homes in Austin, TX
Full text linkWith climate change, the summer heat will become more intense, putting the habitability and thermal comfort of buildings in question. Last year, Texas experienced a record number of heat-related deaths with several occurring as a result of a lack of air conditioning. To determine the impact of climate change on single-family homes in Austin, we used building models from ResStock with weather files generated by Meteonorm to simulate building performance under various weather scenarios. We then used thermal comfort indices such as heat index, discomfort index, and activity hours to evaluate trends in the building stock. The results showed that a preventing blackouts should be the top priority for thermal comfort, since even an air conditioner that is undersized for increased loads under climate change can still offer some cooling and relief as opposed to a complete loss during a blackout.Civil, Architectural, and Environmental Engineerin