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Daily Online Experiences of Marginalization Stress and Social Support for LGBTQIA+ Young Adults
No full textLGBTQIA+ young adults face systemic and interpersonal marginalization and minoritization. These experiences occur not only in offline spaces but also in online contexts. However, online contexts also allow for LGBTQIA+ individuals to access social support that extends and bolsters the support they may receive offline. Previous studies tend to examine the relation between stress and support for LGBTQIA+ individuals using cross-sectional methods, despite the emphasis of previous theories such as minority stress theory on the occurrence of stressors on a daily, cumulative basis. The current study investigated how daily online marginalization stress experiences related to online experiences of social support for LGBTQIA+ young adults. Participants included 177 young adults, ages 18-29 and who identify as part of the LGBTQIA+ community.Participants completed baseline measures of demographics, lifetime experiences of marginalization stress, social media use and attitudes, perception of online social support, self-esteem, and mental health symptoms. Next, participants were prompted twice daily for 21 days to complete a survey about online marginalization stress experiences, general and LGBTQIA+-specific online social support experiences, and positive and negative affect. Finally, participants completed a follow-up survey measuring internalized stigma, community connectedness, self-esteem, and mental health symptoms.Results suggested that online marginalization stress was related to daily affect but not to follow-up well-being outcomes. Online marginalization stress was also related to online general social support, but not LGBTQIA+-specific online support. General social support online was related to higher positive affect and lower negative affect, and LGBTQIA+-specific online support was related to higher positive affect, but both types of online social support were generally unrelated to follow-up outcomes. Low marginalization stress and low general social support together were associated with higher internalized stigma and lower self-esteem at follow-up. Differences in these effects generally emerged for individuals with marginalized sexual orientations and less so for individuals with marginalized gender identities. The results of the study suggest that daily online marginalization stress experiences are likely related to online social support, and that online social support is beneficial for daily affect. However, online social support may not be particularly beneficial for ameliorating the effects of online marginalization stress on affect or well-being
Polarization and Switching Dynamics Study of Ferroelectric Hafnium Zirconium Oxide for Feram and Fefet Applications
No full textAs a scalable and CMOS compatible novel ferroelectric material, the ferroelectric HZO thin film has been the promising material for various applications and continues to attract the attention of researchers. Achieving strong ferroelectricity and fast switching speed in ultrathin FE HZO film are crucial challenges for its applications towards scaled devices.The ferroelectric and anti-ferroelectric properties of HZO are investigated systematically down to 3 nm. The ferroelectric polarization, switching speed and the impact of ALD tungsten nitride electrodes are studied. Record high Pr on FE HZO and record high PS on AFE HZO are achieved with WN electrodes, especially in ultrathin sub-10 nm regime. The polarization switching speed of FE and AFE HZO, associated with C-V frequency dispersion, are also qualitatively studied. On the other side of the scaling limit, ferroelectric/dielectric stack superlattice structure is found to enhance the ferroelectricity in thick films which would have severely degraded.Ultrafast direct measurement on the transient ferroelectric polarization switching is used to study the switching speed in FE HZO with a crossbar MFM structure. Sub-nanosecond characteristic switching time of 925 ps was achieved, supported by the nucleation limited switching model. The impact of electric field, film thickness and device area on the polarization switching speed is systematically studied. The ferroelectric switching speed is significantly improved compared to previous reports and more importantly is approaching GHz regime, suggesting FE HZO to be competitive in high-speed non-volatile memory technology. Record fast polarization switch speed of 360 ps is obtained in sub-μm crossbar array FE HZO MFM devices. It also unveils that domain wall propagation speed in HZO is the limiting factor for switch speed and more aggressively scaled devices will offer much faster switch speed.The first experimental determination of nucleation time and domain wall (DW) velocity by studying switching dynamics of ferroelectric (FE) hafnium zirconium oxide (HZO) was performed. Experimental data and simulation results were used to quantitatively study the switching dynamics. The switching speed is degraded in high aspect ratio devices due to the longer DW propagation time or with dielectric interfacial layer due to the required additional tunneling and trapping time by the leakage current assist switch mechanism
Will Spacing Retractions Modulate the Continued Influence Effect?
No full textGlobally, the misinformation crisis exposed the need for cognitive researchers to investigate interventions that will mitigate the influence of misinformation within memory. One proposed solution is a retraction, whereby misinformation is indicated to be inaccurate. Previous studies have demonstrated that providing a retraction after misinformation may reduce references to misinformation. The continued reliance on misinformation even after it has been corrected is known as the continued influence effect (CIE). It is unclear whether repeated retractions and the spacing of repeated retractions can reduce the CIE. In the present study, two experiments were conducted to investigate whether spacing repeated retractions among news messages would be more effective at reducing the CIE compared to massing retractions. Both experiments exposed participants to a news story containing misinformation. Each experiment included four retraction conditions: no retraction, a single retraction, or repeated retractions that were spaced or massed. In Experiment 1, a single retraction reduced reliance on misinformation, but we did not observe an additional benefit of repeated retractions when there were two retractions. In Experiment 2, we provided participants with three repeated retractions. Using this stronger manipulation, repeated retractions reduced references to misinformation compared to a single retraction, but there was no benefit of spacing them out. Collectively, our results suggest that repeating corrective messages can help reduce references to misinformation, with no supporting evidence that it matters how the repetitions are organized
The Impact of Community Engagement on Undergraduate Social Responsibility Attitudes
Get PDFThe literature on student development cautions that social responsibility attitudes may stagnate or decline as students proceed through college. Given the importance of students’ future professional obligations to society, identifying ways to reverse this trend is crucial. In turn, an important aim of this study, situated at a large public university, is to evaluate the prospects of community engagement as a strategy to foster professional social responsibility development. The study uses longitudinal results from an instrument known as the Generalized Professional Responsibility Assessment (GPRA) to assess personal and professional social responsibility attitudes. The study’s sample includes 128 students who completed a survey both in 2017, when entering college, and in 2019, when near the midpoint of college. Findings indicate that social responsibility attitudes remain stagnant, and that students over that time period attach more importance to salary as compared to helping people when considering job priorities. Yet, results reveal that increased community engagement predicts growth in social responsibility attitudes, even when controlling for students’ pre-college social responsibility attitudes and demographic characteristics. Further, a novel contribution of this study is a focus on two sub-categories of community engagement: discipline-based and peer-based. Discipline-based community engagement appears to foster professional aspects of social responsibility, while community engagement experiences tied to peer interaction appear to exert greater impacts for non-White students. An observation derived from the study is that community engagement, particularly when it connects to a student’s discipline or draws on peer influences, could be an effective strategy to promote social responsibility development
Investigating Consistency Among Bridge Inspectors Using Simulated Virtual Reality Testbed
Get PDFThe current condition of US infrastructure requires a data-driven, risk-based approach to asset management. In the case of bridges, inspectors in every state visit these structures and collect data, and based on the information they report, state departments evaluate bridge conditions, predict deterioration, and make repair and retrofit decisions. However, the capacity of inspectors for defect detection might vary due to several factors, such as the inspectors’ experience or eyesight, which results in differences when reporting their results. Through the development of a virtual reality (VR)-based testbed, the variability among inspectors in examination and documentation practices in steel and concrete bridges in Indiana will be measured and analyzed. As a result, training programs could be enhanced according to the outcome analyses of the VR system
Skeletal Muscle Microvasular (Dys)Function: Mechanisms and Therapeutics
No full textOxygen (O2) plays a crucial role in the energy metabolism of complex multicellular life on earth. Due to the small and finite energy stores in the body, fine-tuned changes within the body are required to meet metabolic demand during skeletal muscle contractions, such as during exercise and activities of daily living. The skeletal muscle microcirculation is one of the last steps in the O2 transport pathway from the lungs to muscle cells and represents the largest surface area for O2 and substrate exchange. When skeletal muscle O2 uptake increases during contractions to meet metabolic demand, there must be an increase in muscle O2 delivery. To achieve these elevations in O2 delivery, vessel (arteriole) diameter in the microcirculation is increased, known as vasodilation. This process in the skeletal muscle microcirculation is regulated by several factors, such as neurohumoral, mechanical, endothelial, paracrine, and metabolic influences, which are imperative in properly regulating O2delivery at rest and during muscular contractions. Two vasodilatory pathways of interest in this dissertation are the cyclooxygenase (COX) and nitric oxide (NO) vasodilatory pathways.The primary aim of my dissertation studies was to determine the mechanisms that modulate skeletal muscle oxygenation in health and to define the impact of a potentially effective intervention, whole-body chronic heat therapy (HT), to treat heart failure with preserved ejection fraction (HFpEF). In Chapter 2, we report that acute selective COX-2 inhibition had no effect on resting or exercising skeletal muscle microvascular oxygenation, pulmonary oxygen uptake, or exercise tolerance in healthy young humans. In Chapter 3, we report that NO, via phosphodiesterase type 5 inhibition, regulates myocyte O2transport at rest and during recovery from muscle contractions in healthy young rats. In Chapter 4, we show that whole-body chronic HT promotes central and peripheral adaptations, which impact positively exercise tolerance in a pre-clinical rat model of HFpEF. Specifically, whole-body chronic HT had beneficial influences on exercise tolerance, skeletal muscle oxygenation from rest to contractions (driven, at least in part, by enhanced NO bioavailability), body composition, and cardiac function. Chapter 5 is a summary of the results and limitations of the projects presented in Chapters 2-4, with a brief discussion of potential future research directions
Cardiac Effects of Recurring Autonomic Dysreflexia
No full textPersons with a spinal cord injury (SCI) above the sixth thoracic vertebrae commonly experience autonomic dysreflexia (AD), 90 percent of individuals with this level of injury are susceptible to AD which is associated with an increase in sympathetic nerve activity. Left untreated AD causes a paroxysmal rise in blood pressure that may result in seizures, heart attack, or even death. This project investigates how AD affects QT interval, RR interval, P wave height, heart rate, and QRS width both during an event and long term to help identify potential cardiac risks for individuals with SCI who experience chronic AD. Sympathetic tone has been shown to influence QT interval changes that can be indicative of an increased risk of arrhythmia, which can be exacerbated by recurring episodes of AD.A rat spinal cord injury model at the T3 level undergoing colorectal distention (CRD) was used to induce AD. Electrophysiological recordings from an implanted ECG sensor and noninvasive skin nerve activity (SKNA) sensor array during normal baseline and three trials of CRD were collected on days 5, 7, 9, 11, 14, 16, 19, and 21 post-SCI. Custom MATLAB algorithms were used to identify the QRS complex and T-peaks from the implant ECG signal. QT interval measurements were taken for 2 minutes of baseline and for 2 minutes after the initiation of each CRD trial. Corrected QT interval (QTc) was calculated using normalized Bazett’s formula to account for the impact of heart rate on QT interval.It was found that the rats’ susceptibility and reaction to AD events varied between subacute (5-14 days) and chronic phases of SCI. During the chronic phase the incidence of AD events increased during regular occurrences of CRD as indicated by above-threshold (≥15 mmHg) blood pressure spikes. AD events also resulted in increased QT interval short term variability marking an increased risk of arrythmias. Baseline P-wave height and QTc interval were also increased while QRS complex width decreased resulting in potentially detrimental cardiac effects. This rat model showed that humans who experience recurrent AD during the chronic phase of SCI may be at increased risk for arrythmia