2923 research outputs found
Sort by
The New Bully: Online Racism, Online Sexual Harassment, and Their Association with Aggression and Stress
Full text linkThere has been a great deal of study related to the impacts of traditional bullying and cyberbullying on mental health and similarities found between these variables have led researchers to question whether cyberbullying is a form of traditional bullying or its own distinct variable. By further analyzing the forms of cyberbullying, online racism and online sexual harassment, the present study aims to add to this discussion. Furthermore, there has been little research on these variables since the start of the COVID-19 pandemic. Considering changes in work and school lifestyles during the pandemic, analyzing the associations of online racism and online sexual harassment with mental health outcomes since 2020 can be valuable for researchers, practitioners, and other stakeholders alike. Therefore, the purpose of this study was to examine the relationship between cyberbullying, in the forms of online racism and online sexual harassment, and mental health outcomes, in the forms of aggression and stress, following the pandemic. Specifically, this study investigated if participants with increased experience of online racism and online sexual harassment following the pandemic reported a greater experience of aggression and stress compared to those whose experience of online racism and online sexual harassment did not increase following the pandemic; furthermore, the present study tested the whether there were significant interaction effects between online sexual harassment and racial identity, as well as interaction effects between gender identity and online sexual harassment in their relationship with aggression and stress. The present study also examined whether online racism and online sexual harassment predicted aggression and stress after the experience of traditional bullying is controlled and if online racism and online sexual harassment may interact with each other in their relationship with aggression and stress. 202 participants were recruited through Amazon Mechanical Turk (MURK), an online crowdsourcing platform. They completed the Perceived Stress Scale (PSS-10) to measure their stress and the Buss and Perry’s Aggression Questionnaire (BPAQ) to measure aggression. They also completed the Online Victimization Scale (OVS) to measure their experience of online racism and online sexual harassment as well as the Bullying Scale (BS) for their experience of bullying in the traditional format. A series of Analysis of Variance (ANOVAs) were used to examine the differences in aggression and stress of those who reported increased experience of online racism and online sexual harassment when compared to those whose experience of online racism and online sexual harassment did not increase following the pandemic; in addition, these analyses examined the interaction effects between increased online racism and racial identity as well as the interaction effects between online sexual harassment and gender identity on their relationship with aggression and stress. Hierarchical multiple regression analyses were used to determine if online racism and online sexual harassment predicted aggression and stress above and beyond the impact of traditional bullying and if online racism and online sexual harassment may interact with each other in their relationship with aggression and stress. Results showed that compared to those whose experience of online sexual harassment did not increase following the pandemic, participants with increased experience of online sexual harassment following the pandemic reported significantly greater stress but not aggression; however, there were no significant differences in stress and aggression between participants with increased experience of online racism following the pandemic and their counterparts whose such experience did not change. While results showed that compared to Caucasian participants, participants of a racial minority group reported significantly greater stress, there were no significant interaction effects between online racism and racial identity or online sexual harassment and gender identity in their relationship with aggression and stress. Additionally, hierarchical multiple regression analyses showed online racism and online sexual harassment predicted aggression and stress above and beyond traditional bullying; however, no interaction effect of online racism and online sexual harassment was found on their relationship with stress and aggression. Based on these results, it can be concluded that online racism and online sexual harassment are not forms of traditional bullying because they contribute to mental health outcomes above and beyond traditional bullying. This conclusion has important theoretical implications in that it suggests that researchers cannot assume that forms of cyberbullying have the same associations with mental health outcomes as traditional bullying and encourages future researchers to focus on these separate variables (online racism and online sexual harassment). It can also be concluded that those who have experienced online racism and online sexual harassment following the pandemic possess different relationships in terms of mental health outcomes than those who have experienced traditional bullying. This conclusion has important practical implications in that it suggests that stakeholders may need to approach the prevention and treatment of online racism and online sexual harassment differently than they have approached traditional bullying in the past. Future research could benefit from focusing on examining the impact of these interventions or treatments on online racism and online sexual harassment, where research is scarce
Sleeping Through the Fright: Examining the Role of Posttraumatic Symptoms on the Relationship Between Sleep Quality, Well-Being, and Health
Full text linkAbout one-third of our lives is spent sleeping. While sleep can be delayed to accommodate one’s lifestyle, the effects of inadequate sleep can be significant. Insufficient sleep has been linked to chronic health conditions, such as heart attacks, coronary heart disease, strokes, asthma, COPD, cancer, arthritis, depression, chronic kidney disease, and diabetes (Centers for Disease Control and Prevention, 2017). Sleep disturbances, such as insomnia and nightmares, are prevalent after a traumatic event (B. Caldwell & Redeker, 2005; Spoormaker & Montgomery, 2008) and are often seen as one of the defining characteristics of posttraumatic stress disorder (American Psychiatric Association, 2013; Maker et al., 2012). Well-being is another component that may be associated with sleep and trauma. When factors such as a healthy diet and exercise are explored, sleep quality has emerged as a significant predictor of overall well-being (Wickham et al., 2020). Trauma exposure can significantly hinder one’s well-being. However, aspects of well-being, such as social support and positive interpersonal relationships, can provide a protective factor (Kaniasty, 2012; Shakespeare-Finch et al., 2014; Weinberg, 2016). The present study examined the mediating role of posttraumatic symptoms on the relationship between sleep quality, well-being, and health. This study consisted of 276 participants recruited from Amazon’s Mechanical Turk (MTurk), an online crowdsourcing platform. The results of this study indicated that posttraumatic symptoms do not significantly mediate the relationship between sleep quality and well-being. However, concerning health, the results showed that posttraumatic symptoms fully mediate the relationship between sleep quality and health. Relevant implications of the findings, limitations, and future directions are discussed
On the T-Degree of Anderson Thakur Polynomials in the Case of Fields of Order P Where P Is a Prime
Full text linkThe Anderson Thakur polynomials are of great interest in the investigation of zeta values. Here, we address the question of their degree in finite fields of the form Fp. We define a graph that is closely connected to Anderson Thakur polynomials and which represents a polynomial we denote as Anxn−1. Collections of terms of this polynomial are equating with the vertices of the graph and are vanishing or nonvanishing. The vanishing structure of the graph is analyzed and we conclude with a simple degree formula
Congruences of the Sums of the First rp Fibonacci Numbers
Full text linkThis paper serves as an extension/application of a method detailed by Chang et. al. in two separate papers which worked with sums modulo p for combinatorial sequences, positive integers r, and prime numbers p. Using a known formula, the Fibonacci numbers were converted into a sum of binomial coefficients to apply the aforementioned method. A hypothesis was formed using computational methods, where a pattern was observed to hold for the first 50,000 prime numbers. This claim was then proven following the methodology from Chang et. al. using properties of Laurent polynomials, definitions and theorems related to the Fibonacci numbers, and elements of modular arithmetic including the freshman’s dream congruence identity and quadratic residues. It was found that for r = 1, the sum is congruent to -1 mod p if p is congruent to 2 or 3 mod 5, to 0 mod p if p is congruent to 1 or 4 mod 5, and to 2 mod p if p is 5. For r = 2, the sum is congruent to 0 mod p if p is congruent to 2 or 3 mod 5, to 1 mod p if p is congruent to 1 or 4 mod 5, and to 3 mod p if p is 5. The paper concludes with a conjecture regarding the sum of the first rp Fibonacci numbers for arbitrary r
Annual Report 2024
Full text linkI\u27m excited to share that the 2023-2024 academic year has been another success. While the year has had its share of challenges, our faculty, staff, and students have met every one with the indomitable Bulldog spirit that has defined our University and College for decades.
Faculty and staff continue to impact students through their steady guidance and commitment to the Tenets of Tech, and our students continue to grow - not just academically, but as the leaders of tomorrow. The problems they are solving here have a real and lasting impact on the world around us. You\u27ll learn about some of these impacts here. I invite you to read more about the College on Louisiana Tech\u27s news site (https://www.latech.edu/category/engineering-science/) and to follow us on Facebook, LinkedIn, and Instagram.
I\u27m incredibly proud of our faculty and staff, who have continued to provide our students with opportunities to flex their leadership skills and participate in innovative, world-changing research. I hope you will continue to be a part of what makes this College special next year.
Regards,
Collin D. Wick, Ph.D., Dean and Daniel D. Reneau Eminent Scholar Chair, College of Engineering and Science, Louisiana Tech Universityhttps://digitalcommons.latech.edu/coes-annual-reports/1012/thumbnail.jp
Blow-spun Hybrid PCL-PEO/HNTs Scaffolds with Enhanced Biological and Mechanical Properties
Full text linkWith the development of technology and engineering, nanotechnology has been a multidisciplinary scientific field applied in nearly all science areas, including medicine, genetics, food industry, robotics. In this respect, nanomedicine has gained increasing attention and been a useful, effective therapy for cancer diagnosis, gene transfer, and drug delivery. To design an ideal nano drug delivery system with controlled drug releasing and improved encapsulated drug’s pharmacokinetic and pharmacodynamic profiles, hydrogels and polymer composites have witnessed increased research interest during the last decades. Recently, numerous polymers have been studied to fabricate the ideal wound dressing with biocompatibility, biodegradability, porous structural, and suitable mechanical properties. This research was divided into three projects and aims to fabricate a biocompatible, bioactive, and antimicrobial dressing with appropriate mechanical properties using poly-caprolactone (PCL) and polyethylene oxide (PEO) polymers incorporated with halloysite nanotubes (HNT) and strontium coated halloysite (SrHNT) by solution blow spinning. The first project involves the fabrication and characterization of PCL/PEO composite airbrushed films with different compositions. SEM and digital microscopy were used to observe the morphological characters and study the surface roughness of the polymer composites films. The mechanical properties of the airbrushed nanocomposite fibers were assessed via tensile testing. Additional characterization tests carried out in this project include porosity, degradation, and contact angle testing. The results showed that different mass ratios between PCL and PEO (3:7, 4:6, 5:5, 6:4, and 7:3 wt./wt.) and various solvent concentrations (2.5, 5.0, and 7.5 wt./v%) impact the structure of fibers, which affects the mechanical stress and strain, the degradation and biodegradation rate, and hydrophilicity. The second project involves the characterization of PCL/PEO composite solution spun fibers incorporated with HNTs and strontium coated HNTs. Fourier transform infrared (FTIR spectroscopy, X-ray Diffraction (XRD), and SEM were used to observe the presence of strontium on halloysite and in the fibers. Tensile test and Differential Scanning Calorimetry (DSC) showed the addition of uncoated or strontium-coated halloysites could adjust the mechanical stress and strain and the thermodynamic characteristics of the airbrushed nanocomposite fibers. The results of the antimicrobial activity showed a pronounced inhibition of bacterial growth against both gram-positive and gram-negative bacteria in all fabricated nanocomposites with uncoated or strontiumcoated halloysites, in which the groups with uncoated halloysites have better antibacterial property than the groups with strontium-coated halloysites. The third project involves in vitro assessment of the solution spun PEO/PCL composite fibers for wound healing. Biocompatibility was evaluated by live/dead assay for cytotoxicity, cell proliferation, scratch assay, migration assay, and Picrosirius Red staining. The results suggested that the composite airbrushed fibers were non-toxic and improved cell proliferation and migration on skin dermal fibroblasts. The histological staining showed an increase in collagens. These results suggest that the airbrushed PEO/PCL composite fibers incorporated with halloysites, and strontium coated halloysites could serve as a novel and convenient candidate of wound dressing
Development of an Integrated Workflow for Nucleosome Modeling and Simulations
Full text linkNucleosomes are the building blocks of eukaryotic genomes and thus fundamental to to all genetic processes. Any protein or drug that binds DNA must either cooperate or compete with nucleosomes. Given that a nucleosome contains 147 base pairs of DNA, there are approximately 4^147 or 10^88 possible sequences for a single nucleosome. Exhaustive studies are not possible. However, genome wide association studies can identify individual nucleosomes of interest to a specific mechanism, and today\u27s supercomputers enable comparative simulation studies of 10s to 100s of nucleosomes. The goal of this thesis is to develop and present and end-to-end workflow that serves as a solution for comparative, on-demand simulation studies of nucleosomes. This project provides integrated data managing, a sharing solution, new analysis metrics to investigate DNA kinking, the analysis of nucleosome geometry, and clearly demonstrates the effects of DNA sequence on the gross structure and dynamics of nucleosomes. To achieve this goal, we must develop 1) an integrated data managing and sharing solution; 2) a metric for nucleosomal analysis; and 3) a standard reference for nucleosome geometry. This allows us to determine the effect of DNA sequence on the structure of nucleosomes and the nucleosome positioning. The workflow supports the selection of DNA sequences based on informatics, on-demand overnight simulation of nucleosomes, comparative studies of trajectory analyses, data management and sharing, and analyses of the structure. There are five chapters in this thesis. Chapter 1: Introduction, necessary background and preliminary work by Ran Sun during his Master\u27s research; Chapter 2: TMB Library as a solution to data management and sharing; Chapter 3: New analysis metrics of nucleosomal DNA that reveals the sequence effect on positioning and mispositioning of nucleosomes; Chapter 4: The structural analysis of the nucleosome geometry which defines a standard reference for nucleosome modeling; Chapter 5: The end-to-end workflow, NuModeller, integrates all tools and components from above into a Python based package as a sustainable package for the lab
The Impact of Institutional Support on African American Male College Students: A Phenomenological Analysis
Full text linkThis study is a powerful call to action for higher education institutions to recognize and address the unique challenges of African American male college students. Through a qualitative phenomenological approach grounded in Swail\u27s (2004) Framework for Student Success, the study sheds light on the institutional factors that impact the lives of these students. The research design utilized semi-structured interviews with seven African American male participants, and the analysis reveals codes, clusters, and themes that emerged from their narratives, providing valuable insights into the impact of institutional support on their lives. The study highlights the importance of peer support, the challenges faced by the participants, and their maturation process. The research findings contribute to a deeper understanding of the complexities surrounding student success and serve as a foundation for further research in this critical area. In conclusion, this study serves as a wake-up call for higher education institutions to take action and address the systemic barriers that prevent African American male students from accessing and completing higher education. By fostering a development philosophy and providing enhanced institutional support, institutions can ensure that all students have an equal opportunity to succeed and reach their full potential
Phase Interface Dynamics and Heat Transfer Mechanisms in Evaporating Droplet and Pool Boiling Processes
Full text linkDespite the significant importance and widespread use of phase-change cooling techniques, there are still fundamental questions about the microscopic processes that govern the heat transfer mechanisms. In order to gain a better understanding of the underlying physics involved, it is essential to have information at the microscale regarding the surface temperature distribution with time as well as the location and speed of the moving contact line (MCL). A comprehensive understanding of heat transfer mechanisms and phase-interface behavior during phase-change cooling is crucial for improving heat transfer models, optimizing surface engineering, and maximizing overall effectiveness. Firstly, this dissertation presents a capacitance-based microdevice capable of tracking a moving phase interface at the microscale for unconstrained liquid droplets. This microdevice is comprised of an array of planar interdigitated electrodes beneath a thin insulating polymer layer. During the experiments, monitoring changes in capacitance with time facilitated sensing the MCL location and speed as it passes over each capacitance sensor. This capacitive sensing scheme is noninvasive to the system under study, allowing its implementation into many types of existing hardware and devices and not requiring optical access to the phase change area of the device. Implementing multiple capacitance sensors in adjacent proximity for a semiconducting based demonstrated a few limitations, including coupling effects, but it did not prevent the effective detection of MCL. Utilizing a dielectric substrate demonstrated notable improvements, including but not limited to increased capacitance signal outputs and reduced coupling effects for multiple sensors in adjacent proximity. Moreover, this sensing scheme demonstrated the efficient tracking of MCL during droplet evaporation across different surface temperatures, establishing its functionality at elevated temperatures and during phase-change heat transfer processes. Next, multifunctional sensing in an evaporation phase change process is demonstrated by combining the capacitance-sensing microsensors with a series of resistance temperature detectors (RTDs) to form a multifaceted MEMS device. This composite MEMS device also includes a resistance heater, making it an independent experimental setup and ensuring its implementation in investigating phase-change cooling processes. The composite MEMS device has been utilized to measure the local heat transfer characteristics and MCL behavior simultaneously for the evaporation of individual sessile water droplets on the heated surface of the device. The microdevice\u27s resistance- and capacitance-based operating principles mean that it can detect temperature changes and track MCL at the microscale in real time, even for applications with limited or no visibility, such as within thermal management hardware or processing equipment. Results of this study showed that the MCL passage precedes the change in local surface temperature, and the duration of the time difference between these events depends on the MCL\u27s speed. In addition, the passage of the MCL accounts for more than 70% of the overall temperature change during the evaporation process. This work also presents a series of studies in which this composite MEMS device was modified to investigate heat transfer mechanisms and simultaneous tracking of the MCL for subcooled impinging droplets across a range of surface temperatures at multiple impact velocities. Experimental results of this study showed that when a droplet impacts a heated surface and evaporates, the process can be divided into two segments based on the effective heat transfer rate: an initial conduction-dominated segment followed by another segment dominated by surface evaporation. Results also showed that heat flux at the solid-liquid interface of an impinging droplet increases with the rise of either impact velocity or surface temperature. Additionally, this study demonstrated that convection within evaporating droplets contributes negligibly to overall heat transfer; instead, heat conduction into the droplet and surface evaporation dominates the process. In the final study presented here, the composite MEMS device was further modified and implemented to measure surface temperature variation and track the movement of the MCL for isolated bubbling events during nucleate boiling of water. Experimental results showed that the rewetting process of the superheated sensing region acted as a fast-quenching event that caused a sharp and sudden temperature drop, and the duration of this event shortened with increasing surface temperature. The bubble nucleation followed the rewetting process and caused a gradual increase in surface temperature as the bubble started to grow with the advancing movement of the MCL. When the growing bubble diameter reached its maximum, the MCL began to recede, indicating the beginning of the rewetting process, which led to the next bubbling cycle. Collectively, this work represents the first known examples of independent microscale sensing of MCL behavior and surface temperatures and does so for multiple instances of phase change processes. The data produced are analyzed and discussed within the content of fundamental heat transfer processes and prior works. Major findings are presented and guidance on next steps and future studies are provided
Impact of Student Beliefs and Self-Efficacy on Performance in Higher Education STEM Courses
Full text linkIn engineering education, students often face feelings of inadequacy, leading to academic struggles and potential dropout. This dissertation investigates the impact of interactive course materials on students\u27 confidence and self-efficacy in problem-solving, focusing on an Engineering Materials class at Louisiana Tech University. Over four quarters, involving seven sections and 218 students, a 13-question Likert scale survey was administered repeatedly, alongside demographic data and textbook usage surveys. The study aims to compare students’ attitudes and beliefs when not using a textbook versus when using an interactive web-native book. Hypotheses suggest that the interactive book will enhance problem-solving beliefs, confidence, and grades. Additionally, the study examines the relationship between self-efficacy and performance, particularly comparing female and male students. By identifying critical points of struggle and improving real-world connections, this research contributes to enhancing learning experiences and retention efforts in STEM education. Results from a two-sample t-test reveal significant effects on students\u27 beliefs in problem-solving skills when using the interactive web-native book. Linear regression analyses indicate significant predictive effects of the interactive book and honors status on exam scores and final grades. Correlation analysis demonstrates moderate positive correlations between exam scores and final grades. In addition, students with higher self-efficacy exhibit significantly better performance on exam 2 and final grades compared those with lower self-efficacy. Gender differences reveal that male students consistently report higher self-efficacy. In addition, summary statistics of the exit survey and interactive textbook reveal varying levels of engagement and satisfaction with the materials. Overall, these findings provide valuable insights into the efficacy of interactive web-native books in enhancing student learning experiences, performance, and self-efficacy in engineering education