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Association Between Polygenic Scores for Brain Structure and Alzheimer\u27s Disease
No full textAlzheimer’s disease (AD) is a progressive neurodegenerative condition and the most common type of dementia. Research has shown that volumetric changes in subcortical brain structures, which make up roughly 25% of the brain\u27s total volume and affect many physiological functions. This research project aims to investigate the genetic association between brain structures and AD. GWAS data of eight different brain structures (ICV, accumbens, amygdala, caudate, hippocampus, pallidum, putamen, and thalamus) were used to create polygenic scores (PGSs) in a discovery (cases/controls = 2,651/2,768) and replication dataset (cases/controls = 553/644). We utilized PRSice-2 software to generate PGSs and assess genetic correlations using two models: one adjusted for principal components (PC1 and PC2), and another incorporating sex, age, and APOE e4 allele count. Meta-analyses were conducted for discovery and replication samples using random and fixed-effect models with p\u3c0.05 being significant. Mendelian Randomization (MR) analyses were conducted between brain structures and AD. The PGSs of three brain structures–amygdala, hippocampus, and pallidum–were significantly associated (p\u3c0.0133) with AD in the fixed effects model, showing that a higher volume of these structures is inversely correlated with AD. However, the association did not remain significant for the hippocampus after being adjusted for covariates, suggesting that the association between the hippocampus and AD may depend on these covariates. MR analysis indicated hippocampal volume had an inverse causal effect on the development of AD, underscoring the critical role of the hippocampus in the disease\u27s progression.https://oasis.library.unlv.edu/durep_posters/1250/thumbnail.jp
Cellular Mechanisms of Embryonic Eye Regrowth in \u3cem\u3eXenopus Laevis\u3c/em\u3e
No full textThe African Clawed Frog, Xenopus laevis, has been an indispensable model organism for over 100 years in the study of embryogenesis and development. In recent years, this vertebrate model has emerged as a robust tool for deciphering the cellular and molecular mechanisms underlying various modes of tissue, limb, and organ regeneration. In the context of eye repair, Xenopus offers a unique model, where the adult frog eye has limited regenerative capacity compared to its pre-metamorphic embryonic and tadpole forms, which exhibit a robust capacity for regrowth. Understanding the intricate molecular mechanisms that underlie this developmental shift in regrowth ability has the potential to inform our efforts to develop future directed regenerative therapies for eye regrowth. However, to reach this point, a crucial first step of identifying the participating cell populations and intrinsic regenerative strategies used by Xenopus must be decoded. To this end, we have developed a lineage tracing protocol with EosFP, enabling precise labeling of cells within Xenopus laevis throughout its developmental stages. This method, now adapted for use in studying Xenopus eye development, has broadened our knowledge of the internal dynamics of multipotent retinal stem cells within the developing eye, a task not yet achieved with previous labeling technologies. This approach allowed for the labeling of select cells within the eye field through embryonic development, revealing that retinal progenitor cells (RPCs) proliferate and differentiate within their region of origin in the eye field to form the subsequent mature anatomy of the retina. Furthermore, by photoconverting Eos protein in the eye field and subsequently removing the labeled optic vesicle, we have shown that RPCs within the post-surgical wound serve as a source of regenerative cells for the embryonic Xenopus eye. Surprisingly, our results also suggest that cells within the optic fissure of the regenerating eye might originate from a non-RPC lineage. This work advances our understanding of eye development and regeneration in Xenopus, while providing a powerful new tool for future research. By deciphering the natural regenerative strategies employed by Xenopus, we open the door for facilitating directed therapies that mirror proven natural regrowth processes
Music and Narrative Memory
No full textMusic can overlap with many activities, but its effects on our memory for those activities are not fully understood. The experiments here investigated the effects of calm and intense background music on both memory and narrative transportation (the feeling that one is absorbed into the events of a narrative) during reading. Participants read narratives either in silence or with background music and completed a measure of narrative transportation (Transportation Scale-Short Form; Appel et al., 2015). Participants were then tested, either in silence or with background music, on memory for explicit details and inferences from the narrative. Across both experiments, memory task performance was consistently better for inferences compared to explicit details. In Experiment 1, encoding condition showed a non-significant trend toward an effect on memory task performance, with slightly better memory when narratives were accompanied by calm music during reading than by silence. Breaking it down further, participants who enjoyed the music and participants who felt the music matched the narratives showed a benefit of music accompanying the memory task. In Experiment 2, for intense music, participants who felt the music did not match the narratives showed a benefit of silence accompanying the memory task. Overall, this study showed that the ability of music to benefit memory for a narrative seems to be dependent upon both the music and the individual reading the narrative. Future research could explore a wider variety of music, participant-selected music, a longer retention interval, and music intended to match the narrative
Exploring the Experiences of Nursing Faculty Working with Standardized Patients in Simulation: A Mixed Methods Study
No full textNursing faculty in pre-licensure nursing programs are a vital component to simulation education, development, and implementation. With the ongoing challenge of the current healthcare climate, the lack of clinical sites and faculty shortages put high-fidelity simulation in the forefront of nursing education, being relied upon more than ever. To simulate the role of the patient in simulation education, there are two primary modalities that are utilized: manikins and standardized patients (SPs). While not a new approach, SP use in prelicensure nursing education is widely under-researched and the wealth of research surrounding the efficacy of simulation education for student learning does not fully encompass the perspective of the nursing faculty working along SPs in the simulated setting. Due to this significant gap and risk to clarity and standardization of simulation delivery, a mixed methods study was conducted to explore the experiences and perceptions of faculty who utilize standardized patients in simulation. This study aimed to answer the following research questions: What are the experiences of nursing faculty working with Standardized Patients in Undergraduate nursing simulations? What aspects of SP and faculty interaction are most likely to affect student learning outcomes in simulation
Cultured Coils: A Multiple Case Study Exploring Black Mothers’ Hair Choices and the Impacts on Their Black Daughters
No full textBlack hair is culturally significant and a form of self-expression for Black women. The literature reviewed about Black women and their hair focused on Black women and their hair experiences but did not explore the ways in which the generational impact or influence of those hair experiences. This study employed the theoretical frameworks of Collins (i.e., Black Feminist Thought) and Crenshaw (i.e., Intersectionality) to explore how Black women think about Black hair and how those thoughts impact the choices they make regarding their and their daughter’s hair. A qualitative method of an exploratory multiple case study, utilizing semi-structured interviews, was used as it allowed the researcher to describe the participants’ experiences while respecting the uniqueness of each individual participant. Black mothers (n = 4) who have Black daughters between the ages of 3 and 17 were interviewed to investigate Black mothers’ hair choices and the impacts of those choices on their Black daughters. Four themes emerged from the findings of this study including a) Black hair is enough, b) natural hair is the best option for Black hair, c) childhood hair shame, and d) breaking the cycle. These findings implicated that despite the disproportionate complex forms of external and internal factors that shape and influence how Black mothers view themselves and their hair, they are still able to have positive, beneficial experiences with their Black hair and share in those positive experiences with their Black daughters. The recommendations from this study are for a) parents to continue utilizing resources to facilitate discussion about Black hair, b) educators to incorporate more representation of Black hair within the curriculum, and c) policymakers to pass laws in all 50 states to address the ongoing discrimination of Black hair in schools and the workplace
Self-Regulated Learning through Self-Concordant Goals, Social Modeling and Sustainability Focus
No full textResearch has shown that when students spend time reflecting and autonomously selecting their college goals, they show high intrinsic motivation, low extrinsic motivation and improvement in emotional and social adjustment over the first several months of college. Despite of this, it is estimated that 77% of first- and second-year students are undecided on their major and many remain undecided as they transition into their junior and senior year. Moreover, in education settings the primary emphasis is on academic success, but focusing solely on academic goals is limiting. As learning is inherently social, academic and social domains cannot be separated, while social goals act as motivators for learning behaviors and increase academic and social competence. Therefore, the goal selection process deserves a lot more consideration and attention than is currently given. To this aim, I used Self-Determination Theory (SDT) and its offshoot, The Self-Concordance Model (SCM) as a framework for the contention that academic/career, well-being and social goals should all be relatively aligned towards the betterment of self and the society at large. This case study contributes to the goal selection literature by offering insights on group projects that incorporate SCM and SDT principles under a self-selected common purpose. The interviews conducted at the end of the semester showed the unificatory power of a self-selected common purpose during their group projects, however the leap from group projects centered around grand challenges to similar interdisciplinary majors was not always obvious to the students
Cultivating Nursing Student Competency Through Serious Gaming Simulation-Enhanced Prebriefing
No full textProblem: Simulation is an effective teaching strategy for undergraduate nursing students, providing a safe environment for learning in a low-risk setting. However, students are not fully prepared to take full advantage of high-fidelity simulation activities. The purpose of this study was to examine the impact of serious gaming simulation-enhanced prebriefing on student competency and simulation effectiveness. Methodology: The study employed a quantitative, cross-sectional, quasi-experimental design using secondary data. Participants included undergraduate nursing students in a southern private university. The students were enrolled in the prelicensure nursing program and the obstetric or the transition to practice course. The control group received a traditional prebrief, high-fidelity simulation, and debrief while the intervention group received a serious gaming simulation-enhanced prebrief, high-fidelity simulation and debrief. Student competency was assessed using the valid and reliable Creighton-Competency Evaluation Instrument (C-CEI) while simulation effectiveness was measured by the Simulation Effectiveness Tool-Modified (SET-M). Data Analysis: Independent t-tests were run to compare the means of the SET-M and C-CEI total scale scores between study groups. MANOVAs was completed to examine the mean differences in C-CEI and SET-M subscale scores between the control and intervention groups. Although there were statistically significant outcomes with the clinical judgment and communication C-CEI subscales, the implications of these results are limited due to the small sample size and low reliability of the CCEI in this study. Implications: The results help to focus future research on the best methods to improve student performance during high-fidelity simulation and to demonstrate student competencies
Understanding Failure Mechanisms for Two Colorectal Anastomosis Techniques
No full textColorectal Surgery continues to be one of the most common gastrointestinal surgeries performed in the US. A common complication known as Anastomotic Leakage (AL) that threatens up to 30% of patients with this surgery. Many cases of AL can decrease the quality of life for patients or extensively extend hospital stays, and in many cases, lead to death. Researchers have studied this complication in clinical trials, yet few studied the mechanics of stapled anastomosis in controlled environments. The purpose of this research was to understand the mechanical interaction between the staples and the tissue, and to eventually apply it in a Finite Element Model (FEM). In doing so, the aim is to develop a resource “playground” for staple manufacturers to test and enhance current designs of staples and different anastomosis techniques before going to clinical trials. Firstly, to understand the colon tissue, an anisotropic -hyperelastic material model was introduced and calibrated to tensile testing data collected from freshly harvest porcine colon tissue. An initial FEM was developed to show the effectiveness of the model in predicting the stress and strain properties that were experimentally verified. Next, colon specimens were harvested from porcine tracts to compare two types of anastomosis techniques, End to End (EE) and End to Side (ES). Additionally, a control section of the tract was harvested to be used as a benchmark of a healthy colon tract. These specimens were subjected to burst testing to simulate the inflation of the colon, and burst pressures were recorded when AL occurred. The results showed no difference in the burst pressures of the EE and ES techniques, however showing more similar behavior of time to failure and expansion of ES and Control vs EE. Using this data, three FEM were developed to compare to the three specimens subjected to burst testing. The results showed a clear correlation to the experimental data
Dynamic Model of an Overhead Crane
No full textIn this thesis a novel spatial model of an overhead crane was developed. The model includes: bridge, trolley, driving and follower wheels for the bridge and trolley, drum, cable, and the payload. The model accounts for the winding/unwinding of the cable around the drum as the payload is raised/lowered. The cable and the payload were considered as rigid bodies with uniformly distributed mass. First, the kinematic equations of the model were developed by using constraint equations. Second, the dynamic equations were derived through use of Newton’s Laws. Developing the rotational dynamic equations required the determination of the angular momentum vectors of the rigid bodies as expressed with respect to an inertial frame. However, the orientations of the rigid bodies were described using Euler angles, which are neither absolute angular coordinates nor described with respect to an inertial frame. Hence, a novel derivation of the angular momentum vector with respect to an inertial frame in terms of Euler angles and local parameters was developed. In addition, a new approach for deriving the dynamic equilibrium torque of the drum was developed; this method used the constraints forces instead of the positions, velocities, and accelerations of the bodies. The motion of the system was simulated with bang-bang inputs and the results prove that the model is stable
A Transcription for Piccolo Trumpet with Historical Context and Methodology: Oboe Quartet KV 370/368B by Wolfgang Amadeus Mozart
No full textThis document explores the challenges of transcribing Mozart\u27s Oboe Quartet for piccolo trumpet, emphasizing performance practices. Both oboe and trumpet navigate mid-high to high ranges with fluidity, underscoring the importance of mastering flexibility through study and practice. This document examines the process of transcription by comparing other successful transcriptions.Achieving balance among instruments is crucial due to the piccolo trumpet\u27s volume compared to the oboe or violin. Careful dynamics adjustment ensures harmonious blending within the ensemble, allowing each instrument to shine without overpowering the others. Breath management poses another significant challenge, and while similarities between oboe and piccolo trumpet breath control make the quartet suitable for transcription, performers must adapt their approach to meet the trumpet\u27s unique demands. By focusing on precise attention to detail and mastering transcription techniques, musicians can successfully navigate the transcription challenges. This process preserves the integrity and beauty of Mozart\u27s original composition and showcases the unique capabilities of the piccolo trumpet. The document will equip future trumpeters with transcription skills used to add new repertoire for the piccolo trumpet