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Effects of Common H1-Antihistamines on IL-6 and RANKL Expression in Osteoblasts
No full textOBJECTIVEH1-antihistamines are the treatment of choice for prevention and relief of symptoms associated with allergic rhinoconjunctivitis which affects 18.9% of children and 25.7% of adults in the United States. The purpose of this study is to evaluate the expression of RANKL, OPG and IL-6 in human osteoblasts, G-292 osteosarcoma cell line, following treatment with varying concentrations of histamine and common second-generation H1-antihistamines including fexofenadine (Allegra), cetirizine (Zyrtec), and loratadine (Claritin)
METHODS In this in vitro study, G-292 cells were cultured in 6-well plates with McCoy’s medium. The cells were treated with histamine at a concentration of 0.01, 0.1, 1 or 10 µM and then incubated for 24- or 6-hours prior to mRNA isolation. mRNA expression of HRH1, RANKL, OPG and IL-6 were measured using quantitative PCR. To compare the effects of antihistamine treatment on G-292 cells, cell cultures were treated with 1 µM of histamine and fexofenadine, cetirizine and loratadine were added at concentrations of 0.01, 0.1, or 1 µM. mRNA expression of RANKL and IL-6 were measured using quantitative PCR. Luminex Milliplex assay was completed on extracted media from the samples to evaluate protein expression of IL-6. Mann-Whitney U Test was completed to determine statistical significance (P value \u3c 0.05).
RESULTSStimulation of G-292 cells with varying concentrations of histamine does not result in a statistically significant change in mRNA expression of HRH1, RANKL or OPG at both treatment times of 6- and 24-hours. The increased expression of IL-6 is statistically significant at higher concentrations of 10 µM after incubation at 24-hours and 1 and 10 µM at 6-hours. The results suggest that there is a positive correlation between histamine concentration and IL-6 expression. Treatment of G-292 cells with histamine and different types and concentrations of fexofenadine, cetirizine and loratadine did not result in statistically significant changes in RANKL mRNA expression. The results suggest that there is a negative correlation between antihistamine concentration and IL-6 mRNA expression for fexofenadine and cetirizine. At the concentration closest to Cmax for each antihistamine, there is a statistically significant decrease in IL-6 expression for fexofenadine and cetirizine, but no change is observed for loratadine. The data from the Milliplex assay evaluating protein expression of IL-6 supports the qPCR results.
CONCLUSIONSThe results from this in vitro study suggest that loratadine may be a better option compared to fexofenadine and cetirizine with regards to maintaining the rate of orthodontic tooth movement since there were no significant changes in IL-6 expression noted between the treated cells and the positive control
Heat Transfer Enhancement in Heat Exchangers Using Compound Enhancement
No full textThis research will try to investigate the enhancement of heat transfer in a heat exchanger that is made of a corrugated tube that has a twisted plate inserted in it, the corrugation, and twisted plate are expected to increase the amount of heat transfer since the plate is acting as a connection between the center of the flow and the edges of the tube. The turbulence will cause an increase in pressure drop along the channel length, so the investigation will try to find the best compromise between the gain in heat transfer and loss of hydraulic energy by using well-established metrics. A positive heat transfer gain has been achieved if that metric indicates a value equal to or greater than 1. This CFD research will be compared with the experimental results by Zimparov (2012). After validating the CFD results it is proposed to investigate a new insert geometry to further improve the efficiency of the said heat exchanger.
The computational fluid dynamics (CFD) simulation was conducted to investigate and validate the CFD model, which evaluates the heat transfer performance in a spirally corrugated tube that has a twisted tape inserted. The heat transfer was then compared to a simple corrugated tube without the twisted tape and to a smooth tube with no corrugations and no twisted tape
Evaluation, Rating, and Numerical Modeling of a Shock Mitigation Seat for High-Speed Craft Based on Laboratory Single Impact Testing
No full textHigh-speed craft (HSC) are utilized in military and para-military maneuvers that are usually conducted in harsh environments. The Special Warfare Combatant-craft Crewmen (SWCC), a sub-unit of the United States Naval Special Warfare Command (NAVSOC), use an advanced HSC, known as the Combatant Craft Assault, to conduct coastal patrol and interdiction, and for infiltration and exfiltration of Navy SEALs. The United States Coast Guard, and the Drug Enforcement Agency (DEA), employ HSC for maritime patrol and to pursue ‘go-fast’ boats operated by contraband runners. In most of these intense applications, the mode of operation of the HSC results in planing. Planing occurs when the weight of the craft is largely supported by hydrodynamic lift, as opposed to hydrostatic lift. That is, the force that is normal to the fluid flow, not the buoyancy force (upthrust), is the force that sustains the partially immersed craft. The severity of these operations, in conjunction with the planing phenomena, create extreme dynamic environments that subject the HSC occupants to mechanical oscillations and shock pulses due to wave slam events. A wave slam is the violent impact between a waterborne craft and an incoming wave, and the shock created by the impact is the predominant cause of musculoskeletal injuries sustained by HSC operators and passengers.
Over the years, shock mitigation seats have been installed in HSC to diminish the rate of injury among on-board personnel. The consensus is that the design of a shock mitigation seat is based on finding a balance between comfort (from the seat cushion material) and shock mitigation capability. However, the varying characteristics of shock loads experienced at sea, makes it challenging for seat manufacturers to develop a seat that performs satisfactorily across the response spectrum of interest.
In addition, currently, a universally accepted measurement system to classify, or rate, shock mitigation seats does not exist. Consequently, it is difficult for potential shock mitigation seat clientele to make an informed decision when considering seats for a specific operating environment. Ultimately, the goal of this study was to develop a repeatable procedure to quantify the performance capabilities of a shock mitigation seat that would facilitate identifying its operational envelope. In addition, this endeavor also sought to develop a computer based numerical model of the system to validate the empirical results, and to characterize the dynamic response of the seat. The test protocol was based on requirements presented in a proposed ISO Standard, as well as guidance developed from research that was conducted by the United States Naval Surface Warfare Center Carderock Division (NSWCCD). However, en route to accomplishing the objectives, two questions – the answers to which were integral to the outcome of the study – had to be addressed.
The first query explored if the use of a single impact drop tower was a plausible method to simulate the rapidly applied vertical shock that is associated with a wave slam event experienced by an HSC. The NSWCCD has recommended using a mass-spring-damper model as the basis for the analytical representation of a shock mitigation seat. Hence, the second inquiry aimed to verify if the [HSC]-[seat-occupant]-[wave] global system could be appropriately modeled using the mass-spring-damper analytical representation of the seat.
Testing revealed that a drop tower, with certain hardware configurations, was a feasible option to simulate the vertical shock that is associated with a wave slam event. The tower was fully capable of testing to a severity threshold level of four (6.12 g), according to the recommended testing levels for military and commercial craft outlined in the ISO and NSWCCD documents. Using the tower, the seat was rated for use in vessels ranging from HSC Class 3 to HSC Class 4-3 for operating conditions that match severity threshold level four. The mass-spring-damper model proved to be a credible approach to the analytical representation of the shock mitigation seat.
A numerical analysis, conducted with SDOF and 2DOF models based on the mass-spring-damper concept, produced simulated acceleration data that agreed with the experimental data collected during the drop tests. The simulated acceleration and position data was effective in validating the empirical data, and a consolidated analysis using both the SDOF and 2DOF approaches provided an acceptable characterization of the dynamic response of the seat
Female Adolescent Cyberbullying: Exploring Students\u27 Intentions to Pursue a Postsecondary Education
No full textDoes cyberbullying influence female adolescent students’ postsecondary decisions in the U.S.? Using routine activities theory, this quantitative study explored if cyberbullying was related to female adolescent students’ intentions to attend a college, postsecondary vocational school, and graduate from a 4-year college. Data were gathered from the 2019 National Crime Victimization Survey: School Crime Supplement (NCVS-SCS). The final sample comprised 102 female adolescent students in the U.S. aged 12-18 years old, and the data were analyzed using multinomial logistic regression. Results showed there were no statistically significant relationships overall between cyberbullying and female adolescent students’ intentions to attend and graduate from postsecondary institutions. However, cyberbullying had a limited association with female adolescent students’ intentions to graduate from a 4-year college if students spread rumors or tried to make others dislike them. Ancillary research is needed to examine this predictor in greater detail. These findings helped contribute to the literature and advance the topic of cyberbullying among female students aged 12-18 years old. Additionally, this study offered intervention strategies, implications for practice, and recommendations for future research
An Analysis of Truancy Causes and Prevention Programming in Clark County, Nevada
No full textIn the United States truancy prevention is lacking two key elements to success; research that explains the causes of truancy and empirical evidence for best practices of truancy prevention. Truancy has been a problem in academics since the early 1900’s, when truancy became illegal. Since then, truancy rates have continued to see a steady increase, and today approximately 10% of public school students in the United States are truant every day (Maynard et al., 2017). To combat this problem, research needs to be conducted to understand why truancy happens. However, there is a severe lack of research on this topic; without understanding why truancy happens how can prevention programs effectively lower truancy? There is also a lack of studies that examine and build a list of best practices for truancy prevention programs to follow.This study aims to fix both of these gaps in the literature surrounding truancy while also helping a community-based truancy prevention program. In Clark County, Nevada truancy among its student population is over 30%. The Truancy Prevention Outreach Program (TPOP) was created to combat the growing truancy rate by using a whole-family wrap-around approach and providing services to the whole family to help students stay in school. This study consists of quantitative and qualitative data provided by TPOP with the goal of understanding truancy causes and if the programs methods are effective. The quantitative data examined the effectiveness of the program as well as how the effectiveness effected academic achievement. These results showed that the program was effective in lowering truancy rates and as attendance increased so did the students’ academic achievement markers. The qualitative data was examined for evidence behind the cause of truancy, and how families reacted to the program. The themes found in the qualitative data suggest that the family connection is the most important reason why the program was effective and that the reasons for truancy are vast. Finally, a mixed methods analysis was conducted using both the quantitative and qualitative data, which examined the data for explanations as to why the program worked well for some students and not for others. This study brings to light more questions regarding truancy research and paves the way for more research in this area to be conducted. The results of this study were also used by TPOP as evidence that the program does work and guided them to finding areas for improvement. The results of this study provided statistically significant findings that can help to build a set of best practices for truancy prevention program in the future
Monstrous Women: Adaptation as Humanization
No full textIn recent years there has been a rise of retellings of Greek myths which have recaptured the imagination of contemporary readers, greatly propelled by social media. Many of these retellings center female and LGBTQIA+ voices which have previously been silenced by ancient authors. This thesis focuses on two of the most maligned women in Greek mythology, Helen of Troy and Medusa, in two recent novels, Daughters of Sparta and Stone Blind. Through an application of monster theory and adaptation, both characters are given voice and made “human”
The Mitochondrial Membrane Potential as a Screening Tool for Immunostimulation
No full textThe rise of neuroinflammatory disorders highlights the importance of early detection and intervention for more effective treatment options. Neuroinflammation is associated with the pathogenesis of many neurological disorders, including Major Depressive Disorder, Alzheimer\u27s disease, and Multiple Sclerosis. There has been a focus on neurons to advance our understanding of the underlying mechanisms of neuroinflammation and its role in neurodegeneration. However, recent studies have highlighted the pivotal role of glial cells, particularly microglia, in neuroinflammation due to their active participation in the immune response. This study investigates glial-specific indicators of morphology, metabolic changes, and drug efficacy in neuroinflammatory conditions. By analyzing the glial-specific activity of microglia at various levels, we uncover distinct patterns that correlate with disease progression. These findings offer insights into the early stages of neurological diseases and provide potential biomarkers for early detection. Moreover, this study explores the modulation of microglial metabolic activity as a screen for therapeutic approaches. We examine the impact of pharmacological interventions on glial cells and their subsequent effects on disease outcomes. In summary, this dissertation expands the current understanding of the dynamic interplay between glial cells, neuroinflammation, and disease progression, ultimately contributing to the development of a novel drug screening tool. Identifying glial-specific metabolic indicators and evaluating drug efficacy offer promising avenues for early detection and targeted therapeutic interventions in neurological diseases
“A Contradiction to Being a Teenage Girl”: Identity Gaps as Conceptualization Turning Points for Girl Activists
No full textThis study employed a turning point analysis to document milestones that influence the development of activist identities in young girls. All participants (N = 19), between the ages of 16–23 years old, self-identified as an activist and participated in activist spaces. Through an analysis of semi-structured interviews and arts-based elicitation research, data revealed several turning point events that influenced participants’ activist identity development, as well as their personal definition of activism. These turning points, paired with the communication theory of identity (CTI) framework, highlighted how girl activists negotiate gaps in their activist identities by communicatively co-constructing an evolving definition of activism. Theoretical and practical implications are discussed regarding turning points in relation to identity development and gendered disparities in activist spaces
Aberrant Creativity: AI Art Exhibition Catalyzing Conversations Among Artists, Educators, and Professionals
No full textThe Aberrant Creativity exhibition was the culmination of an in-depth exploration of Generative AI in arts and creativity by a group of faculty at Texas A&M University\u27s School of Performance, Visualization & Fine Arts. Their investigation delved into how artists have been incorporating artificial intelligence (AI) into their creative practices, with a focus on the concept of AI as a collaborator in the creative process. The exhibition brought in 38 unique pieces from around the world, from artists who each had their own approach to human-computer co-creativity. The event facilitated rich discussions among artists, students, faculty, and the public, fostering a deeper understanding of AI\u27s impact on art. Despite some social media controversies we encountered, the exhibition successfully engaged the community and underscored the importance of open discussion over the integration of AI technology in creative practices. Moving forward, the organizers aim to provide better contextual education of GenAI to audiences and to put more emphasis on displaying the creative process in future exhibitions. This initiative shines a light on the evolving relationship between technology and creativity, advocating for ethical practices and collaboration in AI-driven art
Beyond the Waterfall: A Review of Project Management Methodologies in STEM
No full textProject management has been exercised from the early stages of history to concurrent practices happening today. It has evolved from the early stages of the Gantt chart and five primary principles to well-renowned project management methodologies such as Waterfall and Agile. This literature review focuses on comprehending four project management methodologies (Waterfall, Agile, Kanban, and Scrum), learning their criteria and frameworks, and learning about their application in a specific STEM environment when applicable. This work reviews the recent research literature pertaining to these four methods. An overview of project management certificates and guidelines is covered as well. Waterfall is known to be a traditional method, having linear and sequential phases to complete a project. Agile, on the other hand, focuses on an iterative cycle while prioritizing customer involvement. Kanban and Scrum, being derivatives of the Agile methodology, focus on visualization as a main communication platform and Sprint meetings, respectively. The results from this study show that the project’s environment is significant alongside the execution of the project management methodology. Further research hopes to focus more on differing STEM environments such as electrical engineering and biological sciences