University of Southern Mississippi
Aquila Digital Community (University of Southern Mississippi, USM)Not a member yet
11361 research outputs found
Sort by
Tuning the Morphology of Triblock Copolymers via Homopolymer Blending
Get PDFMorphology plays an important role in the physical properties of block copolymer (BCP) materials. Depending on the type of morphology and chemical composition of the blocks, BCPs are used in applications ranging from soft biomaterials for biomedical devices to rigid materials for ballistics protection. Due to incompatibility between comonomers and required block weight ratios to achieve targeted morphologies, it is generally necessary to use complex, time-consuming, and expensive synthetic techniques to prepare BCPs. As a result, there is increased interest in the development of new processing methods to tailor block copolymer morphology without the need for additional synthesis. The morphological effects of blending polystyrene (h-PS) and polyisobutylene (h-PIB) homopolymers of varying molecular weights with poly(styrene-b-isobutylene-b-styrene) triblock copolymers were investigated. Homopolymers and triblocks were synthesized and structures confirmed via nuclear magnetic resonance spectroscopy and gel permeation chromatography. Small-angle X-ray scattering was employed to evaluate morphology and domain size. It was found that block length, molecular weight, identity of added homopolymer, and solvent all affected equilibrium morphology. Theoretical morphology predictions based on the ratio of homopolymer blended with the BCP for diblock copolymer/homopolymer blends were found to not hold for our triblock systems
Transcriptional Analysis of Inflammatory Responses of Mouse Trophoblast Stem Cells to Interferon Gamma
Get PDFThe blastocyst faces significant immunological challenges during implantation, including heightened inflammation, which can contribute to implantation failure. Trophoblast stem cells (TSCs) and their differentiated forms (TSC-TBs), derived from the trophectoderm (TE) of the blastocyst, play a crucial role in immune modulation. Previous studies suggest that interferon-stimulated genes (ISGs) derived from TSC and TSC-TB provide antiviral protection to embryonic stem cells (ESCs). These findings show indication of a potential antiviral role for placental progenitors in shielding the blastocyst. Additionally, TSCs and TSC-TBs exhibit selectively attenuated immune responses to the proinflammatory cytokine interferon-gamma (IFN-γ) compared to mouse embryonic fibroblasts (MEFs). The attenuated immune responses are likely to prevent cytotoxicity and inflammation that could compromise implantation. However, a comprehensive analysis of IFN-γ stimulated ISG expression in these cells remains limited. Through bioinformatic analysis of RNA-seq datasets, this thesis reveals that TSCs and TSC-TBs exhibit a selective and attenuated response to IFN-γ, characterized by reduced expression of IFN-γ receptors—likely limiting signal transduction and downstream activation of key transcription factors. The analysis of ISGs involved in cell cycle, cell growth, apoptosis, and stress response provide further evidence of the reduced TSCs and TSC-TBs responsiveness to IFN-γ. However, despite the overall dampened response, a subset of immune-associated ISGs remains modestly upregulated following IFN-γ exposure, prompting speculation that these low expression levels might hold physiological significance in providing immune protection to the blastocyst
An Objective Structured Clinical Examination (OSCE) for Spinal Anesthesia Utilizing Landmarks and Ultrasound Guidance
No full textSpinal anesthesia, a critical regional anesthetic technique, is frequently administered by Certified Registered Nurse Anesthetists (CRNAs) for a variety of surgical procedures, especially those involving areas below the umbilicus. However, CRNAs\u27 experience with spinal blocks may vary when transitioning to new hospital environments, necessitating continued education and skill assessment. This doctoral project aims to address the knowledge gaps through the development of an Objective Structured Clinical Examination (OSCE) specifically designed for CRNAs.
The OSCE incorporates current best practices and research on spinal anesthesia, offering CRNAs an instructional framework for administering spinal blocks using both traditional landmark techniques and ultrasound guidance. The OSCE provides a platform for potential skill enhancement, allowing CRNAs to refine their knowledge, proficiency, and confidence, ultimately leading to improved patient care and outcomes. This doctoral project highlights the importance of standardized competencies and ongoing education for CRNAs in spinal anesthesia administration. These efforts can benefit patients by reducing postoperative complications and improving recovery outcomes.
An email was sent to local CRNAs requesting participation in reviewing and evaluating the Spinal Anesthesia OSCE utilizing both landmark and ultrasound techniques. The email included informed consent, the OSCE template, and a Qualtrics©survey link. After reviewing the OSCE, participants completed the anonymous survey rating their knowledge and confidence in administering spinal anesthesia using a Five-Point Likert Scale. The survey results indicated that 100% of participants agreed that incorporating this OSCE into continuing education could benefit CRNAs in reviewing spinal anesthesia
The Effect of Implementing a Development Program Using Mental Imagery on the Time to Master Psychomotor Skills
Get PDFPsychomotor skills development programs that use mental imagery have been demonstrated to help individuals acquire psychomotor skills (Anu et al., 2020; Seymore-Walsh et al., 2020; Toth et al., 2020). The commercial trucking industry is presently experiencing a global shortage of qualified truck drivers (American Trucking Association, 2019; Staats et al., 2017). One reason individuals are avoiding or leaving careers as commercial truck drivers is the time spent away from home (Staats et al., 2017). A couple logistical strategies have been developed to improve the situation (Mittal et al., 2018; Prime Inc, 2024); however, for the solutions to be sustainable, the industry will need to have access to more qualified drivers (Mittal et al., 2018). The present study aimed to determine if using mental imagery combined with physical practice would aid individuals that were attempting to master psychomotor skills required to pass the entry level driver training skills test.
The study used a quasi-experimental posttest only design (Shadish et al., 2002). The researcher used a census of students enrolled in an 8-week course truck driving program. The participants were divided into control and experimental groups based on their ability to use mental imagery as measured by the vividness of movement imagery questionnaire (VMIQ) (Isaac et al., 1986). The cognitive, affective, and psychomotor perceived learning scale (Rovai et al., 2009) measured the perceived effectiveness of the programs to teach the content; and instructors provided a tally of each driver’s attempts to measure efficiency (Caruso, 2022). Frequency distributions were used to report demographic data. Central tendencies were reported for years of experience operating a commercial vehicle and ability to produce a vivid mental image. The researcher intended to use a one-way analysis of covariance (ANCOVA) to compare the perceived effectiveness of the programs and to compare the efficiency of the programs based on the participants’ number of attempts. However, data failed the assumptions for both perceived effectiveness and efficiency during analysis; so the researcher compared the programs using a Mann-Whitney U test for both perceived effectiveness and efficiency
The Influence of Snapchat Consumption on Saudi Women’s Self-Perception and its Relation to The Desire to Change Their Appearance: A Quantitative Approach Applying Cultivation and Social Comparison Theory
No full textAbstract
This dissertation examined Saudi women’s exposure to Snapchat content related to cosmetic procedures, including news and content creators, and its impact on their self-perception, including self-esteem, body satisfaction, perception of beauty standards, and desire to change appearance through cosmetic procedures. This study utilized cultivation and social comparison theory as theoretical groundings. An online questionnaire was distributed among Saudi women (N=307) which was analyzed using multiple statistical tests, including correlation, regression, and mediation analysis, found causal relationships and statistical significance between the variables. The findings revealed that the amount of time spent consuming news about cosmetic procedures led to a low level of self-esteem among Saudi women, but the exposure to content creators, regardless of the amount of viewing, also had an impact. The findings also indicated that consuming both news and creators’ content related to cosmetic procedures on Snapchat led to an increase in achieving beauty ideals and, thus, the desire to change appearance by undergoing cosmetic procedures. In particular, the amount of viewing of the creator’s content had an impact on both previous dependent variables. Also, it found that social comparison behavior mediated the relationships as it led to a negative impact on Saudi women’s self-esteem and body satisfaction but raised the desire to reach more beauty norms and the desire for change. However, no mediation for religiosity was observed between the variables.
Keywords: Content creators, Cultivation theory, Media consumption, Saudi Arabia, Self-perception, Social comparison theory, Snapcha
Perceptions of Choral Diction Curricula
Get PDFThis study proposed to provide in-depth insights into the current status of the efficacy of diction curricula, as well as to seek ways for enhancing the curricula to better support a culturally diverse musical experience. 21st century choral music encompasses languages and music from all over the world. While this diversity is crucial to the idea of a global choral community, it necessitates choral conductors to be scholars of diction, which includes creating the appropriate sounds for a given language. For a conductor to confidently perform in global languages requires skills, resources, and tools. This study examined the diction coursework that choral musicians are exposed to within the three-degree levels – undergraduate, master’s, and doctoral – and further investigated the efficacy of the coursework as it applies to the modern choral folder. To accomplish this, the study employed a mixed methods research design by conducting both qualitative and quantitative survey, constructed and distributed via Qualtrics, of recent graduates of choral conducting programs largely in the Southern Region of the United States. The study’s findings reveal a need for a restructuring of diction curricula to better serve the diverse languages of the contemporary choral folder. This dissertation includes an appendix to guide readers through resources intended to aid conductors in better instructing students in the languages of the contemporary choral folder with a specific focus on the International Phonetic Alphabet (IPA), a globally-accepted system of characters for codifying the phonemes of the world’s languages
Examining the Mediating Effects of Symptoms of Depression, Anxiety, and Perceived Stress on the Association Between Bereavement and Inflammation
No full textBereavement is a stressor that impacts the psychological well-being of an individual and their physical health. This study aimed to develop a more nuanced understanding of the association between bereavement and its psychological and biological consequences, and the potential mediating role of symptoms of depression, anxiety, and stress within the relationship between bereavement and inflammation. Data was collected through Midlife in the United States (MIDUS) Refresher 1, a longitudinal study that examines social, psychological, and biological vulnerabilities associated with potential health outcomes (Weinstein et al., 2019). The study consisted of 863 participants (bereaved=373, non-bereaved=490) who completed an in-person study visit which involved answering self-report questionnaires and a venipuncture blood draw to examine inflammation. An independent samples t-test found no differences in psychological health (i.e., stress, depression, and anxiety) and no differences for inflammatory markers CRP and TNF-α between bereaved and non-bereaved individuals; however, an independent samples t-test found higher IL-6 among bereaved individuals. An ANCOVA found significantly higher levels of depression, anxiety, and perceived stress among bereaved individuals compared to non-bereaved individuals, while considering covariates. Further, an ANCOVA found higher levels of IL-6 and TNF-α in bereaved individuals than non-bereaved individuals, but no differences in CRP. Mediation analyses found that psychological symptoms did not have an indirect effect on the relationship between bereavement and inflammation. Overall, the findings inform clinicians and physicians of the unique needs of bereaved individuals, such as early psychological intervention in the bereavement experience, potential need to change health behaviors, and health education to stave off the negative consequences of bereavement
A Psychometric Evaluation of the PBSS-20 Among Sexual and Non-sexual Minority College Students
Get PDFThis study evaluated the psychometric properties of the Protective-Behavioral Strategies Scale-20 in a large national sample of college students containing sexual minority and non-sexual minority students. Specifically, confirmatory factor analysis was used to evaluate the model fit with this sample, invariance testing was used to compare the model among sexual and non-sexual minority students, and construct validity was evaluated. Participants included college students (N = 1,730; Mage = 19.41) from 12 universities across the United States, who were predominantly White non-Hispanic (63.6%), identified as female (70%), and as completely heterosexual (67.6%). Participants completed demographic information and measures of hazardous alcohol use, weekly drinking, alcohol-related negative consequences, and use of alcohol protective behavioral strategies (PBSA). Results revealed an adequate model fit of the PBSS-20 for the current sample, supporting the hypothesized factor structure. Invariance testing revealed that the PBSS-20 demonstrated invariance for sexual and non-sexual minority college students. The PBSS-20 total and subscale scores were negatively associated with every alcohol outcome measure for all samples, as expected. Results support the use of the PBSS-20 with sexual minority college students. This study expands the generalizability and utility of the PBSS-20 with both non-sexual minority and sexual minority college students across the United States