Evaluation of a Bisphosphonate Enriched Ultra-High Molecular Weight Polyethylene for Enhanced Total Joint Replacement Bearing Surface Functionality

Each year in the United States there is an increasing trend of patients receiving total joint replacement (TJR) procedures. Approximately a half million total knee replacements (TKRs) are performed annually in the United States with increasing prevalence attributed to baby-boomers, obesity, older, and younger patients. This trend is also seen for total hip replacements (THRs) as well. The use of ultra high molecular weight polyethylene (UHMWPE) inserts in TJRs results in wear particle-induced osteolysis, which is the predominant cause for prosthesis failure and revision surgery. Sub-micron size particle generation is inevitable despite the numerous efforts in improving this bearing material. Work by others has shown that the use of oral and intravenous systemic bisphosphonates (BP) can significantly minimize periprosthetic osteolysis. However, the systemic delivery and the high solubility of BPs results in a predominant portion of the drug being excreted via the kidney without reaching its target, bone. This doctoral research project is focused on the development and evaluation of a novel method to administer BPs locally using the inherent wear of UHMWPE for possible use as an anti-osteolysis treatment. For new materials to be considered, they must be mechanically and tribologically comparable to the current gold standard, UHMWPE. In order to evaluate this material, mechanical, drug elution and tribological experiments were performed to allow assessment of material properties. Tensile tests showed comparable yield stress and pin-on-disk testing showed comparable wear to standard virgin UHMWPE. Further, drug elution tests have shown that BP was released from the enriched material both in static and dynamic conditions. Additionally, an aggressive 2 million cycle total knee simulator experiment has shown statistically similar wear results for the two materials. Overall, this research has provided the groundwork for further characterization and development of a new potential material for total joint replacements as an enhancement to standard UHMWPE. This material shows significant potential as an alternative bearing material to indirectly increase TJR longevity by addressing osteolysis related issues

Generalization of executive function skills in inclusion settings for students with Asperger\u27s syndrome

The purposes of this single case investigation were to research the effects of an intervention designated to prepare a student with Asperger\u27s Syndrome for placement within a public high school. The student attended a specialized private school for grades 3-8. Upon entrance into eighth grade, the student entered the intervention program. This program included placement in a mainstream eighth grade social studies class with the accompaniment of the examiner. The intervention included daily feedback and strategies aimed to increase occurrences of task completion, increase executive function skills within the class setting, and decrease maladaptive behaviors. The identical areas of interest were sent to the student\u27s current public high school teacher for rating. Findings reveal an increase in student\u27s overall points earned as indicated by archival data for the intervention year. During the non-intervention year, teacher-reported points decreased significantly. This indicates that while the intervention increased the student\u27s success in a mainstream setting (the eighth grade Social Studies class), these skills were not, however, generalized to the mainstream high school setting

Advanced Air-Side Heat Transfer Surface Geometries Enabled by Additive Manufacturing

In a world with a decreasing supply of fresh water, industry is looking for design solutions that depend less on the availability of water. Dry-cooled condensers are one possibility, but they must compete with traditional water-cooled condensers in terms of cost, performance, and fan power. To improve performance, air-side heat transfer designs must be improved. Additive manufacturing offers the freedom to create designs that are difficult to manufacture with traditional methods. While the materials for additive manufacturing are not as conductive as the metals used in conventional heat exchangers, highly filled polymers do allow an improvement in conductivity and strength over traditional materials used in 3D printing. Also control over the printing material offers advantages such as the use of an antimicrobial infused filament. The ultimate goal of this research is to design an air-side geometry capable of achieving the same thermal performance (heat transfer rate and pressure drop under a given set of conditions) as a “gold standard” heat exchanger but at lower cost (i.e., using less material and/or less expensive manufacturing techniques). Because additive manufacturing allows for freedom in design, unconventional air-side geometries have been investigated using Computational Fluid Dynamics (CFD). The typical evaluation process for each geometry that has been considered includes an initial CFD simulation to validate the results and mesh convergence followed by an extensive parametric study of the geometry to develop correlations in terms of dimensionless parameters. The correlations are then implemented into an overall heat exchanger model in order to allow optimization of the heat exchanger

Service Induced Byproducts for Localized Drug Delivery in Orthopaedic Implants

A composite material including ultra-high molecular weight polyethylene in conjunction with a biologically active agent is described. The biologically active agent can be, for example, an anti-osteolytic agent such as a bisphosphonate. The composite material can be utilized in forming implants such as total joint replacement implants. The biologically active agent can be released from the composite material either from the bulk or from wear particles released from the surface of the implant component during use. Upon release, the biologically active agent can carry out the intended function of the agent

Research Talks and What It Means to be a Woman in Environmental Science

Dr. April Watson, Archaeologist Everglades National ParkDr. Cassandra Korte, Associate Professor, Scientific Literacy and BiologyDr. Deborah Williams, Assistant ProfessorDr. Marcheta Wright, Professor, International RelationsMs. Maria De Almeida, Lynn Graduate Student, M.S. Biological Science

Professional Education to Reduce Provider Stigma Toward Harm Reduction and Pharmacotherapy

Aims: A novel professional training was developed to reduce stigma toward harm reduction and pharmacotherapy for substance use disorders. Methods: The training was delivered over three sessions to n = 147 health professionals in Utah between 2019 and 2020, including n = 40 substance use disorder treatment professionals. Pre and post-training survey measures provided evaluation information on knowledge, attitudes, and planned action regarding harm reduction and pharmacotherapy. Items were grouped into a stigma score, and multilevel modeling, regression analyses, and McNemar tests were used to quantify changes in overall stigma toward harm reduction interventions both before and after the training. Results: The training significantly decreased the total stigma score toward harm reduction (b = -0.09, p \u3c .001, β = -0.34). At the individual item level, 6 of the 22 items showed significant change in reduced stigma (all p \u3c .047), and all items moved in the direction of decreased stigma. These items include both attitudes and planned action aspects of the total stigma score. Conclusions: This study suggests that education targeting prejudice and discriminatory actions against harm reduction and pharmacotherapy interventions among healthcare professionals may contribute to stigma reduction. These results provide a basis for intervention effectiveness, addressing preconceived ideas, and show community need for such substance use interventions, as a component of future stigma reduction efforts

Personal and reported partner pornography viewing by Australian women, and association with mental health and body image

Background: Personal and partner pornography viewing may affect health and wellbeing. This study aimed to improve understanding of the effects of pornography on mental health and body image, given emerging evidence of increasing use, particularly among young people. Methods: A cross-sectional survey was implemented, targeting people who had accessed health and fitness content via social media. Convenience sampling was used and participants were recruited via advertising on social media. Results: Overall, 76% (75/99) of women reported having ever viewed pornography, and 21% had viewed pornography frequently (monthly/weekly/daily) in the prior 12 months. The association between frequent viewing and higher-risk Kessler 10 Psychological Distress Scale scores lost significance once controlled for age (adjusted OR 2.30, 95%CI 0.82–6.49, P = 0.11). There was an association with frequent reported partner pornography use (monthly/weekly/daily) and increased Drive for Muscularity scores (adjusted OR 2.20, 95%CI 1.01–4.80, P = 0.048). There were no other associations found with pornography use (personal or partner) and body image or mental health, although this was limited by the small sample size. Most women (85%, 41/48) reported being happy with their partner’s pornography use, and in qualitative responses, indicated that pornography had minimal effect on their lives. Nevertheless, multiple qualitative responses indicated a multiplicity of perceived effects of pornography, including negative effects on body image. Conclusions: Pornography had a minor effect on mental health and body image in this study. Additional research is required to improve understanding of the effects of pornography on body image and mental health, particularly among vulnerable individuals

Figuring Out Gas & Galaxies In Enzo (FOGGIE) VIII: Complex and Stochastic Metallicity Gradients at z > 2

Gas-phase metallicity gradients are a crucial element in understanding the chemical evolution of galaxies. We use the FOGGIE simulations to study the metallicity gradients ($\nabla Z$) of six Milky Way-like galaxies throughout their evolution. FOGGIE galaxies generally exhibit steep negative gradients for most of their history, with only a few short-lived instances reaching positive slopes that appear to arise mainly from interactions with other galaxies. FOGGIE concurs with other simulation results but disagrees with the robust observational finding that flat and positive gradients are common at $z>1$. By tracking the metallicity gradient at a rapid cadence of simulation outputs ($\sim 5$--10 Myr), we find that theoretical gradients are highly stochastic: the FOGGIE galaxies spend $\sim 30-50$\% of their time far away from a smoothed trajectory inferred from analytic models or other, less high-cadence simulations. This rapid variation makes instantaneous gradients from observations more difficult to interpret in terms of physical processes. Because of these geometric and stochastic complications, we explore non-parametric methods of quantifying the evolving metallicity distribution at $z > 1$. We investigate how efficiently non-parametric measures of the 2-D metallicity distribution respond to metal production and mixing. Our results suggest that new methods of quantifying and interpreting gas-phase metallicity will be needed to relate trends in upcoming high-$z$ {\it JWST} observations with the underlying physics of gas accretion, expulsion, and recycling in early galaxies.Comment: Submitted to Ap

5-HT₄ Receptor Agonist Effects on Functional Connectivity in the Human Brain:Implications for Procognitive Action

Background: Cognitive deficits are often comorbid with mood disorders and can cause significant functional impairment even after resolution of the primary mood symptoms. We do not currently have pharmacological treatments that adequately address these deficits. 5-HT4 receptor agonists show promise as potential procognitive agents in animal and early human translational studies. Optimal cognitive performance in humans is directly associated with appropriate functional connectivity between specific resting-state neural networks. However, so far the effect of 5-HT4 receptor agonism on resting-state functional connectivity (rsFC) in the brain in humans is unknown.Methods: We collected resting-state functional magnetic resonance imaging scans from 50 healthy volunteers, of whom 25 received 6 days × 1 mg prucalopride (a highly selective 5-HT4 receptor agonist) and 25 received placebo in a randomized double-blind design.Results: Network analyses identified that participants in the prucalopride group had enhanced rsFC between the central executive network and the posterior/anterior cingulate cortex. Seed analyses also showed greater rsFC between the left and right rostral anterior cingulate cortex and the left lateral occipital cortex, and reduced rsFC between the hippocampus and other default mode network regions.Conclusions: Similar to other potentially procognitive medications, low-dose prucalopride in healthy volunteers appeared to enhance rsFC between regions involved in cognitive networks and reduce rsFC within the default mode network. This suggests a mechanism for the behavioral cognitive enhancement previously seen with 5-HT4 receptor agonists in humans and supports the potential for 5-HT4 receptor agonists to be used in clinical psychiatric populations