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Metamemory And Disconfirming Feedback: An Evaluation Of The Blank Lineup Procedure
Get PDFEvaluating an eyewitness for their efficacy is a difficult endeavor. Traditionally, scientists have used post-identification confidence to gauge the accuracy of an eyewitness. Recently, other methods are being explored to evaluate the efficacy of an eyewitness, such as, using blank lineups, measures of metamemory, and pre-identification confidence. The present study evaluated a blank lineup procedure where participants were given disconfirming feedback when they made an incorrect decision on an initial blank lineup. Participants then moved to a target present or target absent final lineup. I sought to evaluate the potential effects of disconfirming feedback using the Eyewitness Metamemory Scale (EMS) and pre-identification confidence. I predicted that participants who receive disconfirming feedback will have lower pre-identification confidence on the second lineup. Furthermore, I predicted that participants who report lower pre-identification confidence will be more likely to make an incorrect decision on the first and second lineup. Finally, I predicted that participants who score high on the EMS subscale for discontentment will have lower overall accuracy. The results found the only significant predictors found were post-identification confidence and the contentment subscale of the EMS. Disconfirming feedback was found to significantly reduce pre-identification confidence, and surprisingly, post-identification confidence among participants. With initial lineup performance failing to predict accuracy, further investigation is required to understand the effects of disconfirming feedback. Keywords: eyewitness, metamemory, blank lineup, pre-identification confidenc
Black Lives Matter: Protesting As A Form Of Communication
Get PDFOn May 25, 2020 in Minneapolis, Minnesota, Officer Derek Chauvin knelt on the neck of George Floyd for 9 minutes and 29 seconds, resulting in Floyd’s death; protests and riots broke out not only in Minnesota, but around the United States (Taylor, 2021). This was just the most recent event in the repeated police brutality against people of color. This dissertation is a case study examining protesting as a form of communication in regards to the Black Lives Matter movement. The deaths of 15 Black people which generated notable media attention are examined via a variety of news sources, starting with the inception of the Black Lives Matter movement in 2012 after the the killing of Trayvon Martin and ending with the murder of George Floyd in 2020. These deaths resulted in different types of protests, which affected both positive and negative outcomes
Determination Of The Water To Cement Ratio Of Fresh Concrete Using NIR Hyperspectral Imagery
Get PDFThe water to cement ratio (w/c) is the primary mix design parameter that will control the strength of a concrete mix. Although a specific w/c is usually stated in concrete mix specifications, there is currently no practical test available that can quickly measure this critical property from fresh concrete. Near-infrared (NIR) Hyperspectral Imagery (HSI) can identify a material by measuring the response of the material to the incident NIR light reflecting off its surface in a range of wavelengths. This measured response can be used to differentiate between unique materials and identify variations of similar materials. This thesis studies the use of the NIR hyperspectral response of fresh concrete as a non-contact tool for determining its w/c ratio. Fresh concrete samples with w/c’s ranging from 0.35 to 0.6 were tested. Multiple spectral feature extraction methods were tried to determine which best could detect changes in w/c. Finally, the change in the hyperspectral response over time was measured. NIR HSI was shown to be capable of predicting the w/c of fresh concrete within ± 0.03 of the design w/c. NIR HSI was also shown to be capable of monitoring the change in free water on the surface of the fresh concrete over the first several hours of the life of the concrete. This thesis is a promising first step in the use of NIR HSI for the quality control of fresh concrete
Advancing Nutrition And Dietetics Students\u27 Preparation For Clinical Practice Through Simulation-Based Learning Experiences
Get PDFThe use of Simulation-Based Learning (SBL) has increased in Nutrition and Dietetic (N&D) programs, although the research supporting its usability in N&D students is lacking. There are limited quality SBL instruments available that have been validated and tested for reliability in N&D students preparing for clinical practice. This three-article dissertation was to test the reliability of three SBL instruments for N&D students completing the Nutrition Care Process (NCP) during SBL activities. During the first phase of this study, two instruments were developed, and one instrument was modified from another SBL instrument that had been previously validated and used for nursing and medical students to align with N&D professional language, and focus on the specific skills necessary to perform a nutrition assessment and complete the NCP. The next phase of the study was aimed at testing the reliability of the instruments. Students participated in two simulation activities that included a prebrief, SBL learning activity, and a debrief. Students were asked to complete two surveys: the Nutrition Simulation Effectiveness Tool-Modified to determine the effectiveness of the SBL activity and the Nutrition Effective Learning Instrument (NEL) to gain perspective of how students perceive SBL influences their learning, preparedness, and confidence in readiness for clinical practice. The Nutrition Simulation Effectiveness Tool- Modified (NSET-M) showed some level of agreement that SBL was effective for N&D students completing prebriefing, learning, confidence, and debriefing while practicing the NCP. The Assessment, Diagnosis, Intervention, Monitoring and Evaluation Simulation Facilitator Instrument (ADIME-SFI) was developed for simulation facilitators observing N&D students completing the NCP. There was moderate agreement between the two facilitators rating the students simultaneously during SBL activities. The Nutrition Effective Learning Instrument (NEL) was used to gain perspective on how SBL contributed to students learning, preparedness, and confidence using the NCP in readiness for clinical practice. Reliability testing determined that the three instruments can be effectively used for N&D students participating in SBL activities. This study contributes to the limited research of SBL in N&D students and offers reliable SBL instruments that can be used for educational purposes; thus, allowing educators to consistently and effectively evaluate student learning and competency in N&D students completing the NCP
Mitigation Of Alkali-Induced Ash Aerosol Particles Impacts On Solid Fuel Combustion Systems
No full textLow-rank solid fuels impact heat transfer efficiency and energy conversion in steam generation, with adverse operational and environmental consequences. Despite the attention coal-biomass co-combustion has garnered as a climate-aware power generation alternative, inorganic species in low-rank fuel types can lead to counterproductive outcomes in combustion systems. However, improved combustion technology and fuel quality enhancement can facilitate the safe utilization of these fuels. A review of scientific literature underscores the need for research in fuel quality improvement as a climate change mitigation strategy during the global transition to renewable energy sources. Identifying problematic species in solid fuels and understanding ash formation mechanisms are therefore critical steps toward designing effective strategies to control ash aerosol-induced fouling.
Methods for promoting clean combustion, including fuel pre-treatment and co-combustion include fuel improvement strategies, such as CFD-targeted-in-furnace injection (CFD-TIFI), intelligent soot blowing, and fuel additive technology, focusing on mineral additives. Due to its high efficiency, low cost, and minimal retrofit requirements, additive technology holds promise for large-scale applications, paving the way for fuel flexibility in utility-scale power generation. The current study emphasizes the importance of fuel ash mineral transformation and characterization techniques for evaluating the effectiveness of fuel additives. Assessing the economic viability and feasibility of large-scale demonstration will however require further research.
Emissions of alkali metals present a notable challenge in combustion systems. Combustion of alkali-rich fuel which leads to troublesome fouling of heat-transfer surfaces, diminishing boiler efficiency, and increasing maintenance expenses would have to be targeted for capture to limit the impacts of these problems. Interaction between sulfur-based compounds and alkali elements facilitates ash bonding and subsequent deposit accumulation on surfaces. While current approaches such as fuel blending and combustion monitoring offer partial mitigation, a more targeted strategy is needed to address alkali vapor release during combustion. This study reports laboratory-scale experiments conducted on a 10-kW down-fired combustor to demonstrate the efficacy of cost-effective clay-based sorbents in capturing vaporized alkali species released during high-sodium fuel combustion. The analysis of ash samples yielded important insights into ash chemical composition, size distribution, and the fate of alkali species, crucial for assessing their potential as fouling agents.Technical investigations were carried out in bench and large-scale demonstrations. Locally or commercially sourced sorbents were combusted with lignite coal from local mines to evaluate sorbent performance and respective capture capacity. The study explores the chemisorption and adsorption properties of various sorbents for sodium capture under high-temperature conditions and specific sodium-to-sorbent ratios. Sorbent properties were characterized using X-ray diffraction (XRD) spectroscopy and scanning electron microscopy (SEM) techniques to identify alkali-active components and their utilization for capture. Sorbents were ultimately characterized by key parameters such as performance, active composition, qualitative stickiness (based on AAEM composition), diluent composition, and ease of grinding.
Results from the simulated combustion environments indicate increased alkali (sodium) retention for all sorbents, with kaolin achieving the highest capture efficiency at 86%, significantly outperforming two commercially procured sorbents, which achieved 53% and 68%, respectively. Locally sourced sorbents showed varied performance, ranging from 31% to 55%. Despite lower reactivity compared to kaolin, locally sourced mine clays demonstrated promising potential due to their high bulk sodium numbers, capturing sodium in particles larger than 1 µm. Interestingly, sorbent capture efficiency did not directly correlate with specific surface area or mean particle size. SEM analysis of captured ash revealed the formation of alkali aluminosilicates, indicating a shift towards insoluble forms. A novel analytical method differentiated elemental sodium into soluble and insoluble forms using a size-aggregated Dekati Low-Pressure Impactor (DLPI+). This serves as crucial quality control for validating experimental results. Local sorbents tended to generate more fine particles under high-temperature conditions than the CS1 sorbent, with kaolin favoring larger particles.
Lab-scale coal/sorbent testing showed sorbents significantly capturing sodium-based submicron-size aerosols, achieving removal rates ranging from 40% to 77%. Coarse sorbent particle size did not hinder alkali affinity, and low-cost sorbent additives performed favorably compared to more expensive commercial alternatives. Further analysis revealed the formation of high-melting sodium aluminosilicates in both fine and coarse sorbents. Pre-experimental material characterization suggests sorbent alkali capture efficiency is primarily influenced by its active mineral composition, with potential additional effects from alkali and alkaline earth metals (AAEM).
Large-scale testing of sorbent injection at the power plant successfully demonstrated reductions in fouling factors, enhanced operational efficiency, and mitigated environmental impacts. Substantial decreases in sodium and sulfur concentrations within the sub-micron-sized fraction of entrained ash were observed at the electrostatic precipitator inlet. The medium injection rate exhibited the most effective performance. Improvements in cleanliness were noted across various boiler sections. Sorbent injection proved to optimize boiler operations and meet environmental regulations. The substantial decreases in sodium and sulfur levels demonstrate the sorbent\u27s ability to improve boiler cleanliness and reduce fouling factors. Further research is needed to determine the extent of ash quality enhancement due to silica enrichment, with potential applications in combustion systems and construction materials.
Through laboratory-scale experiments and large-scale demonstrations, the efficacy of sorbent injection was demonstrated in reducing sodium and sulfur concentrations, thereby improving boiler cleanliness and offering environmental benefits. Moving forward, further research is needed to explore the economic viability and feasibility of large-scale implementation and assess the quality enhancement of resultant ash. These insights will pave the way for more sustainable and efficient utilization of low-rank fuels in the global energy landscape
Development Of Multifunctional Biobased Lubricants From Soybean Oil And Their Tribological Behavior
No full textDepletion of mineral oil leads the researchers to look for renewable oils recently. Soybean, which is one of the most produced crops globally, has been identified as a potential source for such oil. The problem with vegetable oils is, they consist of unsaturated fatty acids which leads to oxidation of the oils. With proper modification and the use of suitable additives, these oils can be adapted for use in various sectors. High oleic oils are becoming increasingly popular due to their high oleic acid content, which is a monounsaturated fatty acid. These oils are gaining attention for their improved stability compared to regular oils. This thesis compared the tribological behavior of high oleic soybean oil with regular soybean after the chemical modification process (Isopropylation) and addition of select additives. Physico-chemical behavior of the sample oils was also analyzed in this study. The findings indicate that in its natural state, high oleic soybean oil outperforms regular soybean oil. However, after chemical modification and the addition of additives, regular soybean oil demonstrates superior performance compared to high oleic soybean oil
Evaluating Pressure Distribution Of Surgical Support Surfaces For Pressure Injury Prevention: Small-Cell Alternating Pressure Mattress, Standard Foam Mattress, And Gel Overlay
No full textPressure injuries are a significant problem in the health care system for patients undergoing long surgeries due to the prolonged time they spend on the surface without moving under the anesthesia effect [6]. This can lead to the occurrence of pressure injuries and can negatively affect patient outcomes and the healthcare system [3]. Current methods for preventing pressure injuries in the operating room include repositioning the patient, using sponges or small gel pads at pressure points, and the use of support surfaces [2]. There is not enough conclusive evidence that states that the use of support surfaces is effective in reducing pressure injuries, although, different types of support surfaces have been studied such as gel overlays and alternating pressure air mattresses [1]. With the complexity of the various factors from both the patient and the devices, there is not enough evidence that concludes the support surface’s efficacy in reducing pressure injuries. This study aimed to compare the effectiveness in terms of pressure distribution of three different support surfaces: foam, gel overlay and alternating pressure air mattress (APAM) support surface. To compare these support surfaces by looking at the pressure, a thin pressure mapping sensor mat was placed between the support surface and the participant’s sacral region for a period of 5 minutes after stabilizing with a sample size of 29 participants. Statistically significant results demonstrated the APAM support surface was higher in peak pressure, but was also effective in reducing the average pressure over a 25 x 25 region by 15.4% with respect to foam and 11.4% with respect to the gel overlay. In addition, other parameters such as Pixel Percentage (PP) was obtained to quantify the quality of offloading of the APAM support surface. PP is the percentage of area under three different thresholds (30, 20, and 10 mmHg), for the Foam surface, the PP under 30 mmHg was 6%, while for the Gel surface and the APAM support surfaces was 8.8% and 29.6%, respectively
Development Of A Comprehensive Ice-Phobicity Test Stand (CIPTS) For Understanding The Fundamentals Of Ice Nucleation And Adhesion
Get PDFFrom the formation of ice on the leading edges of aircraft and their wings, wind turbine blades, and even roadways and powerlines, it is clear that modern infrastructure suffers from ice formation and adhesion. Due to this fact the development of materials and surfaces to mitigate the effects of icing have gained much attention in recent years. While there are many different anti-icing and deicing techniques, the development of intrinsically ice-phobic materials and material surfaces shows the most promise as a passive anti-icing method. In this work an accurate Comprehensive Ice-Phobicity Test Stand (CIPTS) has been created to test two popular definitions of ice-phobicity, ice adhesion strength and nucleation time. Varying material compositions (PTFE and PTFE-ZnO composites) and surface roughness’s (0.14µm≤Sa≤21.79µm) ice-phobic properties are characterized. Analysis of PTFE-ZnO composites has shown that there is not always a direct link between the ice-phobic properties of ice adhesion strength and nucleation time
Promoting Athletic Training Careers Among American Indian And Alaska Native Communities
Get PDFAthletic training, recognized for its role in providing specialized healthcare services focused on prevention, assessment, treatment, and rehabilitation of injuries for the athletic population, represents a growing profession within the healthcare field. As the need and value of athletic training services continues to grow, it is imperative for academic and Federal institutions to adapt programs and policies that reflect the diversity of the communities they serve.
Despite ongoing efforts, which should not be minimized, to promote diversity, equity, and inclusion in the athletic training profession, significant progress remains limited, particularly in increasing representation of American Indian and Alaska Natives (AIANs). Failure to prioritize the recruitment, admission, and retention of a more representative student body in athletic training education programs (ATEPs) will perpetuate existing disparities. This will continue to result in selection of leaders in athletic training who are largely non-Hispanic White, thus continuing a leadership demographic that does not adequately reflect the profession or the populations it serves in terms of cultural, racial, and ethnic diversity.
The disparity in diversity within the athletic training profession emphasizes the broader need for systemic recognition and support, such as Medicare’s recognition of athletic trainers (ATs) as qualified healthcare professionals, to enhance accessibility and quality of care across diverse populations. This recognition would not only enhance healthcare delivery but also support efforts to achieve health equity among AIAN communities. Each of the three products of this dissertation aligns with levels from the social ecological model—personal, relational, community, and societal—providing a comprehensive perspective on the topic.
The first product, grant proposal, focuses on the need to better understand and consider the experiences of AIAN in the profession given that reliable data is either limited or simply nonexistent. This proposal applies a framework inspired by Indigenous teachings of resilience to address gaps in literature on factors that influence the persistence of AIAN in ATEPs. Knowledge used in developing the grant proposal informed the second product, a manuscript. For the second product, a qualitative study was used to identify facilitators and barriers that influence the recruitment, retention, and credentialing of AIAN ATs in ATEPs. Nine individuals who self-identify as AIAN ATs consented to participate in a semi-structure interview. Analysis revealed barriers such as lack of support, insufficient diversity, and cultural insensitivity. In contrast, facilitators included self-efficacy, support network, service orientation, and ceremony or religious faith. The third product, a policy brief, details the dire need to recognize ATs as qualified healthcare professionals under the Medicare program. This change could expand healthcare services, particularly through the Indian Health Service system, in AIAN communities by addressing health provider shortages, insufficient funding, and access to quality health care and services. Collectively, these products address gaps in scholarly literature by highlighting critical steps towards improving AIAN representation in athletic training, fostering inclusivity, and expanding healthcare access
