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The Effect of Extrinsic Staining on 3D Printed Provisional Crowns
No full textObjectives: The aim of this study was to evaluate the color stability of 3D printed resin disks using spectral reflectance data obtained at different time periods after immersion in staining solution.
Methods: Forty identical round disk specimens measuring 10 mm in diameter and 2 mm in thickness were fabricated using CAD/CAM 3D printing resin (shade B1). Half of the specimens (n=20) were polished using an acrylic bur and medium pumice. The other half was left unpolished (n=20). Each group of disks was then immersed in one of the following immersion solutions : artificial saliva, black tea, carrot juice, and red wine. Color difference ΔE was evaluated using a spectral reflectance instrument known as spectrophotometer at baseline, day 1, week 1, week 2 and week 3, against a white background.
Results: Color difference ΔE was measured using CIELAB formula. The mean ΔE values of each group were calculated. The greatest difference in color was observed in the unpolished and polished disks immersed in red wine. Polished disks showed less color difference when compared to unpolished disks. Significant differences in ΔE were detected between polished and non-polished disks immersed in red wine at week 1 (p = 0.0159), week 2 (p = 0.0079) and week 3 (p = 0.0079) and in carrot juice at week 3 (p = 0.0317).
Conclusion: Immersion in different staining solutions caused detectable color difference in the tested materials which was relative to the immersion duration and the staining solution used.
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The color of the 3D printing resins is influenced by the surface finishing, which may result in visually perceptible color differences. The color stability of 3D printing material should be improved to manufacture oral appliances which provide long-term esthetics
Deciphering UV Spectroscopy on Earth and Mars
No full textSpectroscopy consists of a variety of techniques that often probe materials with light. Light can be absorbed and excite particular chromophores that give insight into electronic structure or can be scattered that gives insight into vibrational structure. To enable successful measurements, one needs to understand the technology behind the spectroscopy and what parameters can be adjusted to affect signal to noise. The thesis presented here illustrates how absorption, fluorescence, and Raman spectroscopies can all be employed to determine the structure of molecules on Earth and how we can use analog datasets to predict what we observe on Mars
Identifying Risk Factors for Clostridioides difficile Acquisition from Transmission in Acute-Care Hospitals
No full textBackground:
Healthcare-associated infections develop during or soon after receiving healthcare services or being in a healthcare setting. Clostridioides difficile is a common and preventable healthcare-associated infection. Whole genome sequencing (WGS) can improve differentiation of C. difficile carriage by identifying genetically related isolates acquired from hospital transmission. Risk factors for healthcare-associated C. difficile infections (CDIs) have been identified, but no published study has identified epidemiological factors characterizing risk of transmission in healthcare settings. Identifying risk factors for C. difficile acquisition from transmission can help guide infection prevention interventions to reduce rates of transmission.
Objectives/Aims:
The goal of this study was to identify risk factors for infection with hospital-acquired C. difficile compared to patients with no genetically similar in-hospital patient source.
Method(s) Used/Approach Taken:
Data was collected from the study hospital’s electronic health record (EHR) for all patients with healthcare-associated CDIs during the study period. Cases were defined as patients with CDI whose isolate clustered with another genetically similar isolate, excluding index patients. Controls were patients with CDI whose isolates did not cluster or were an index patient. A prediction model was generated for in-hospital C. difficile acquisition using EHR data. Elastic net regression (ENR) was utilized with ten-fold cross validation to select significant risk factors. All pairwise interactions were formulated and tested for association using ENR. A prediction model was determined using the selected risk factors in a multivariate logistic regression analysis.
Results:
Among 809 patients with healthcare-associated C. difficile, 114 were excluded from the analysis and the study cohort contained 84 cases and 611 controls. The prediction model identified risk factors (transplant procedure, length of stay, antibiotic receipt and a virulence factor gene) and protective factors (autoimmune disorder, ICU admission and virulence factor genes). The fraction of variance explained by this model for predicting C. difficile acquisition was 28.5%. Eight variables predicted >90% of the model variance.
Summary/Conclusions:
Risk factors for C. difficile transmission can help guide infection preventionists in mitigating transmission of C. difficile by implementing targeted interventions and protocols. These would include pre-emptive contact precautions when handling high-risk patients, enhanced environmental cleaning or asymptomatic C. difficile screening
Using Virtual Reality to Unpack the Benefits of Context-Dependent Memory
No full textHow does our environment impact what we will later remember? Early work in real-world environments suggested that having matching encoding/retrieval contexts improves memory. However, some laboratory-based studies have failed to replicate this advantageous context- dependent memory effect. Using virtual reality methods, this work identified circumstances when context-dependent memory effects were most likely to be found. In Study 1, I examined the influence of memory schema and dynamic environments. Participants (N = 240) remembered more objects when in the same virtual environment (context) as during encoding. This benefit to recall memory, however, traded-off with falsely ‘recognizing’ more similar lures. Experimentally manipulating the virtual objects and environments revealed that a relevant object/environment schema aids recall (but not recognition), though a dynamic background does not. In Study 2, I examined whether grasping and interacting with objects would benefit recognition memory, compared to merely looking at the objects. Participants (N = 60) were no more likely to correctly recognize objects that they were able to grasp when making judgments about whether they had been previously seen or not. Furthermore, the virtual reality paradigm was designed to be employed not only for in-lab data collection (Study 1 and 2), but also for remote, world-wide data collection. Advantages and disadvantages of implementing this type of remote virtual reality data collection procedure are discussed. The findings presented here further our understanding of when and how context affects our memory through a more naturalistic approach to studying such effects
The Presence of Neoliberal Ideology in State Charter School Policies
No full textThe United States’ public education system is no stranger to robust efforts of educational reform. The past 50 years have seen various forms of local and institutional attempts to reform the public education system, but perhaps no reform has been as extensive and successful as the charter school movement. Charter schools are publicly funded but privately run schools of choice that prioritize privatization and autonomy above all else. On the surface, they seem harmless to the public education system—simply a reform that puts the power of choice back into parents’ and students’ hands. But charter schools as an institutional reform represent a new kind of threat to our public education system: neoliberalism. Neoliberalism as an ideology postulates free-market ideals, such as competition, individualism, and deregulation, as necessary means for social well-being in all aspects of life, not just the economic sphere. This study uses content analysis with literature-based a priori codes to examine the presence of neoliberal ideals in state charter school policies. All state charter school policies were found to have some level of neoliberal ideology, the most frequent being privatization and regulatory accountability (to their own set of regulations). The results of this study are consistent with previous literature and demonstrate a compelling account of the connection between neoliberalism and charter schools
Health Screening Events as a Community-Clinical Linkages Strategy for Addressing Chronic Illnesses in Black Communities
No full textDisparities in the prevalence, incidence, and mortality rates of various chronic illnesses in the US have been persistent between White and Black populations. One method to aid in alleviating this disparity is through the community-clinical linkages (CCL) strategy of providing free health screenings in community settings that identify risk factors and refer participants to clinical resources. I explored community-based health screening events as a CCL strategy in Black populations through three papers.
The first paper explores data from sixty-three articles about addressing risk factors for heart disease and stroke, breast or prostate cancer, asthma, or diabetes through screening in community-based settings with Black adults throughout the US. The second analyzes transcripts from four focus groups regarding perceived barriers to accessing clinical resources and strategies to promote engagement with resources. Results from those two papers provide programmatic suggestions for the third paper, a process evaluation of a pharmacist-led health screening intervention held throughout Allegheny County, Pennsylvania.
Key findings of this dissertation are: (1) There is a lack of literature on studies that conduct health screening events focused specifically on risk factors for chronic illnesses in Black communities. There is a dearth of information regarding referrals, follow-ups, and demographics. (2) Barriers to access include lack of knowledge, lack of trust in healthcare professionals, transportation, and wait times. Strategies for engagement include using liaisons, creating a central location for resources, and advertising in local spaces. (3) The activities in the program are being carried out with fidelity. Programmatic opportunities include using multiple methods for follow-up to increase success rate, promoting events, centralizing resources, using community liaisons, and utilizing an electronic consenting method and internal database.
Health screening events are a long-standing detection intervention to address chronic illnesses. The lack of evidence regarding linking participants to clinical resources is a detriment in this CCL strategy. However, addressing barriers to access and improvements with following up and documentation processes may address these concerns. These significant findings contribute to chronic disease prevention by providing insight into the breadth of the literature, information on barriers, and an example of an intervention dedicated to alleviating these health disparities
Quality Improvement of Neurosurgical and Orthopedic Instrument Sterilization Workflows: Closing the Performance Gap to Reduce the Risk of Bioburden and Surgical Site Infections in an Academic Medical Center
No full textBackground: Over 51.4 million in-patient surgical procedures are performed in the US each year with 2-4% of patients experiencing surgical site infections (SSIs) (AHRQ, 2019). SSIs increase the risk of morbidity and mortality and disproportionately affect those with low socioeconomic status, comorbidities, or older age. SSIs are the leading cause of hospital readmissions and cost the US healthcare system $3.5-10 billion annually (Seidelman et al., 2023). Proper medical instrument reprocessing is crucial to prevent the transmission of infectious agents and reduce the risk of SSIs (Jefferson & Young, 2014).
Methods: The primary objective of this study was to examine programmatic management issues that could arise in a clinical setting and explore the connections between the various system components that influence efficient and effective instrument reprocessing. Such information would be valuable in preventing errors that impact patient and staff safety. Behaviors, knowledge, and attitudes regarding instrument reprocessing were measured via researcher observations, staff audits, and anonymous staff interviews.
Results: Twenty neurosurgical and orthopedic surgical case carts were observed within a period of six weeks, in which point-of-use cleaning, precleaning, and disinfection were audited. A surgical tray audit tool was assigned to central sterile processing (CSP) staff who performed a total v
of 183 observations. Both enzymatic spray compliance and bioburden incidence were found to vary by surgical service line and the time of procedure. Three employees from each phase of the reprocessing cycle were interviewed to gauge their knowledge of the workflow, identify potential challenges, and provide suggestions for improvement. Staff interviews expressed a resounding appreciation for instrument reprocessing but indicated lack of education and communication to be potential barriers.
Conclusion: The project identified a correlation between enzymatic spray/pretreatment compliance and bioburden incidence. The study found that higher enzymatic spray/pretreatment compliance rates were associated with lower dried blood and tissue levels. Furthermore, bioburden events were more prevalent during off-shift observations than on-shift observations and less pretreatment was employed during off-shift procedures. These results suggest that maintaining high compliance rates with enzymatic spray/pretreatment may reduce dried bioburden levels and prevent bioburden events, particularly during off-shift procedures
Toxicity of mercury and hydroquinone in skin lightening products: popular practice in non-white communities
No full textThe use of skin lightening products (SLPs) containing mercury (Hg) and hydroquinone (HQ) is a worldwide practice among non-white communities. The practice is rooted in historic colonialism and enslavement. Skin whitening is seen by many as a convenient tool for idealization of European beauty standards and overcoming barriers to social and economic mobility, as a matter of colorism. The use of Hg and HQ in SLPs can have potentially harmful effects on human health. Studies have shown that SLPs containing Hg and HQ can cause a range of adverse health effects, including skin irritation, pigmentation changes, and systemic toxicity. Exposure to these chemicals has been linked to the development of serious health conditions such as renal dysfunction, neurological disorders, and even skin cancer. Furthermore, the adverse health effects of these products are not limited to the users themselves, as non-users who come into contact with contaminated surfaces or air may also be at risk. Children and pregnant women are particularly vulnerable to the harmful effects of these chemicals.
Despite efforts to regulate the use of Hg and HQ in SLPs, these products are still widely available on e-commerce, local beauty stores, and used in many countries. The prevalence of counterfeit products from illegal and non-regulated laboratories further exacerbates the problem, as these products may contain even higher levels of these harmful chemicals. This literature review examines the existing research on the adverse health effects of Hg and HQ in SLPs, with a focus on their prevalence and impact on users and non-user household members.
In conclusion, the use of SLPs containing Hg and HQ is a widespread and concerning practice. It can have adverse health impacts on both user and non-user household members. Despite these risks, the practice persists in many regions, reflecting the influence of societal beauty standards and cultural beliefs. However, there is a growing awareness of the potential health risks associated with these products, and efforts are being made to educate consumers and regulate the industry
Equity in Insurance Coverage of Fertility Services for People with Sickle Cell Disease
No full textDefinitions of infertility by insurers in the US as “the inability to conceive during a 12-month period of unprotected [heterosexual] sex” reinforce barriers to reproductive autonomy for people who are queer, single, and for those with medically induced infertility as this language may preclude eligibility for fertility preservation and/or infertility services. Sickle cell disease (SCD) is the most common genetic condition in the US, and people with SCD often experience iatrogenic infertility in response to symptom management and treatment. SCD disproportionately impacts Black and Hispanic people, as only 1.8% of SCD patients are non-Hispanic white. Given inequities in SCD prevalence, this document examines the public health significance of state-level differences in the language of insurance mandates for infertility and fertility preservation services, with a focus on whether infertility definitions allow coverage for infertility and/or fertility preservation services for people with SCD relative to people with cancer. A secondary goal was to assess eligibility for queer and single people relative to cis heterosexual couples. We conducted a scoping review of published literature to identify and analyze language from these mandates. Comparisons between state-level mandates demonstrate gendered language and a skewed focus on iatrogenic infertility among cancer patients with causes for iatrogenic infertility including “surgery, radiation, chemotherapy or other medical treatment affecting reproductive organs or processes”. This language excludes people with SCD who have not undergone curative treatment. Findings suggest that people with SCD, single, and queer people are not equitably covered for infertility or fertility preservation services even when these services are included in their benefits
Using In Vitro Granulomas to Identify the Type 1 And Type 3 Interferons In Granuloma Formation and Antimicrobial Activity
No full textThe interferons (IFNs) include three major categories of cytokine including type 1 (α, β, ε, κ, and ω), type 2 (γ), and type 3 (λ). Type 3 (IFNs) are further classified into IFNλ1, IFNλ2, IFNλ3, and IFNλ4 in humans and non-human primates (NHPs). These cytokines play important roles in immunity against pathogenic microorganisms where in some cases, they confer protection, and in other cases, they promote pathology. In Mycobacterium tuberculosis (Mtb) infection, type 1 IFNs are known well for their pathogenic roles, whereas the role that type 3 IFNs play in TB is less known and has received little attention. To address this knowledge gap, we made granulomas under in vitro conditions by infecting PBMCs isolated from macaques with Mtb. We pre-treated the PBMCs with IFNs and IFN inhibitors to identify their role in early immune responses in TB. We understood that type I IFNs play a crucial role in promoting granuloma formation and maintenance, while IFN λ signaling shows promise to be a regulator. Interestingly, supplementation with exogenous type I IFN led to a modest reduction in granuloma size, while the addition of IFNλ1 or IFNλ4 resulted in a slight increase in granuloma dimensions. This led to our understanding of the contrasting effects of type I IFN supplementation and IFNλ supplementation on granuloma dimensions, suggesting opposing roles in modulating granuloma formation. A lactose dehydrogenase (LDH) assay was performed to determine if IFN inhibition or supplementation had cytopathic effects in each treatment condition and IFN-supplemented conditions were found to be modestly cytoprotective. To determine how cytokine inhibition or supplementation affected immune responses, we measured cytokine and IDO1 expression. A cytokine bead array performed on the supernatants of the samples led to the identification of IL-1β, TNF-α, and IL-6 exhibiting the highest expression after type I IFN neutralization and a downward trend upon IFN supplementation of both type 1 IFN and IFN λ. The data obtained from flow cytometry suggests that myeloid cells didn’t get influenced by type 3 IFNs to exhibit any change in IDO1 expression