Micro-abrasion of Y-TZP in tea

The object of this work is to investigate the micro-abrasion of Y-TZP in tea. This material is a candidate replacement veneer in dental restoration and to date there has been very little work carried out to investigate the wear behaviour in oral cavity conditions. Various additions such as milk and sugar, which affect the solution viscosity and pH, were assessed as part of this work and the results were compared to the performance of the material in aqueous conditions. Wear maps were generated showing the change in wear rate as a function of applied load, viscosity and exposure time

À la Carte Cable: A Regulatory Solution to the Misinformation Subsidy

Although “fake news” is as old as mass media itself, concerns over disinformation have reached a fever pitch in our current media environment. Online media outlets’ heavy reliance on user-generated content has altered the traditional gatekeeping functions and professional standards associated with traditional news organizations. The idea of objectivity-focused informational content has primarily been substituted for a realist acceptance of the power and popularity of opinion-driven “news.” This shift is starkly visible now: mainstream news media outlets knowingly spread hoaxes, conspiracy theories, and the like. This current state of affairs is not some freak accident. The Supreme Court’s First Amendment jurisprudence has led us here. For example, the Court’s decision in Reno v. ACLU subjects government regulation of online speech to strict scrutiny review, hamstringing nearly any attempt at regulation (much less censorship) of online speech by the government. Similarly, content regulation of televised media is covered by the First Amendment’s capacious protections. And while broadcast media was once heavily regulated for content, the FCC’s adoption of deregulation resulted in the eventual repeal of a range of content limitations and requirements for licensees. Designing a content-neutral scheme to regulate media content directly is not only a complex legal problem, but it is also likely a non-starter. State actors are (rightly) unable to censor or remove content based on the ideological leanings of the content, and media disinformation directly implicates political speech about controversial topics. In an era where cross-platform news media is ubiquitous, the legal status quo has effectively ensured media platforms have near-total discretion to control—or more accurately, not control—the truthfulness of disseminated content. However, a market-based, bottom-up approach to content regulation could end-run the problems that plague government regulation of cable media. Industry research has suggested that cable “news” outlets generate more revenue from per-subscriber fees applied by cable companies than from advertising carried by those channels. In terms of cable news, per-channel costs are the highest costs in a monthly cable bill. This means that more than eighty million cable subscribers subsidize content that attracts fewer than two million viewers daily, including misinformation. This paper posits “à la carte” cable packaging as a solution to the subsidy of disinformation. Currently, cable subscribers are forced to buy programming channels even when they would rather not. This is particularly troubling in the case of news information because subscribers who wish to receive some programming are forced to subsidize other news content that may be objectionable. The resulting system of reverse compelled speech means that news organizations keep their subsidy while advocating against the interests of those footing the bill. Eliminating this involuntary subsidy flips the status quo on its head by making trustworthiness part of the bottom line, incentivizing prudent news self-regulation in an entirely content-neutral manner

Prognostic Indicators and Outcome Measures for Surgical Removal of Symptomatic Nonadvanced Cataract

This article is made available in accordance with the publisher's public repositories policy.Objectives To report changes in perceived visual functioning after surgery for symptomatic cataract with preoperative corrected distance visual acuity [CDVA] of 0.4 logMAR or better (Snellen equivalent, 20/50) and to investigate the relationship between any observed changes and preoperative physical characteristics and psychophysical consequences of the lens opacity and any changes in psychophysical findings after the procedure. Methods Eighty-five patients with cataract completed a validated questionnaire concerning functional vision satisfaction and a series of visual performance assessments before and 2 months after cataract surgery. The lens optical density and Lens Opacities Classification System III score of the cataract were recorded. Correlations between changes in the Rasch-analyzed questionnaire score and changes in visual performance after cataract surgery, as well as preoperative psychophysical measures, lens optical density, and Lens Opacities Classification System III score, were determined. Results The mean (SD) questionnaire score improved from 2.15 (0.36) to 1.54 (0.41) (P > .05 for both). Conclusion Psychophysical tests alternative to CDVA better represent improvements in self-reported visual functioning following removal of symptomatic nonadvanced cataract

Introduction of a Toric Intraocular Lens to a Non-Refractive Cataract Practice: Challenges and Outcomes

AIM: To identify challenges inherent in introducing a toric intraocular lens (IOL) to a non-refractive cataract practice, and evaluate residual astigmatism achieved and its impact on patient satisfaction. METHODS: Following introduction of a toric IOL to a cataract practice with all procedures undertaken by a single, non-refractive, surgeon (SB), pre-operative, intra-operative and post-operative data was analysed. Attenuation of anticipated post-operative astigmatism was examined, and subjectively perceived visual functioning was assessed using validated questionnaires. RESULTS: Median difference vector (DV, the induced astigmatic change [by magnitude and axis] that would enable the initial surgery to achieve intended target) was 0.93D; median anticipated DV with a non-toric IOL was 2.38D. One eye exhibited 0.75D residual astigmatism, compared to 3.8D anticipated residual astigmatism with a non-toric IOL. 100% of respondents reported satisfaction of ≥ 6/10, with 37.84% of respondents entirely satisfied (10/10). 17 patients (38.63%) reported no symptoms of dysphotopsia (dysphoptosia score 0/10), only 3 respondents (6.8%) reported a clinically meaningful level of dysphotopsia (≥ 4/10). Mean post-operative NEI VF-11 score was 0.54 (+/-0.83; scale 0 – 4). CONCLUSION: Use of a toric IOL to manage astigmatism during cataract surgery results in less post-operative astigmatism than a non-toric IOL, resulting in avoidance of unacceptable post-operative astigmatism

The Impact of Macular Pigment Augmentation on Visual Performance in Normal Subjects: COMPASS

This study was conducted to investigate whether augmentation of macular pigment (MP) enhances visual performance (VP). 121 normal subjects were recruited. The active (A) group consumed 12 mg of lutein (L) and 1 mg of zeaxanthin (Z) daily. MP optical density (MPOD) was assessed by customized heterochromatic flicker photometry. VP was assessed as best corrected visual acuity (BCVA), mesopic and photopic contrast sensitivity (CS), glare disability, photostress, and subjective visual function. Subjects were assessed at baseline; 3; 6; 12 months (V1, V2, V3 and V4, respectively). Central MPOD increased significantly in the A group (p \u3c 0.05) but not in the placebo group (p \u3e 0.05). This statistically significant increase in MPOD in the A group was not, in general, associated with a corresponding improvement in VP (p \u3e 0.05, for all variables), with the exception of a statistically significant time/treatment effect in “daily tasks comparative analysis” (p = 0.03). At V4, we report statistically significant differences in mesopic CS at 20.7 cpd, mesopic CS at 1.5 cpd under high glare conditions, and light/dark adaptation comparative analysis between the lower and the upper MP tertile groups (p \u3c 0.05) Further study into the relationship between MP and VP is warranted, with particular attention directed towards individuals with low MP and suboptimal VP. Research highlights ► Identifying that macular pigment significantly increased in the active group. ► Less glare disability for subjects with high macular pigment. ► Improved mesopic contrast sensitivity for subjects with high macular pigment. ► Identifying the need for further research in subjects with low macular pigment

Prognostic Indicators and Outcome Measures for Surgical Removal of Symptomatic Nonadvanced Cataract

Objectives: To report changes in perceived visual functioning after surgery for symptomatic cataract with pre-operative corrected distance visual acuity [CDVA] of 0.4 logMar or better (Snellen equivalent, 20/50) and to investigate the relationship between any observed changes and preoperative physical characteristics and psycho-physical consquences of the lens opacity and any changes in psychophysical findings after the procedure

Visual Performance in Patients with Neovascular Age Related Macular Degeneration Undergoing Treatment With Intravitreal Ranibizumab

Purpose. To assess visual function and its response to serial intravitreal ranibizumab (Lucentis, Genentech) in patients with neovascular age-related macular degeneration (nv-AMD). Methods. Forty-seven eyes of 47 patients with nv-AMD, and corrected distance visual acuity (CDVA) logMAR 0.7 or better, undergoing intravitreal injections of ranibizumab, were enrolled into this prospective study. Visual function was assessed using a range of psychophysical tests, while mean foveal thickness (MFT) was determined by optical coherence tomography (OCT). Results. Groupmean (±sd)MFT reduced significantly frombaseline (233±59)) to exit (205±40)) (p = 0.001). CDVA exhibited no change between baseline and exit visits (p = 0.48 and p = 0.31 resp.). Measures of visual function that did exhibit statistically significant improvements (p \u3c 0.05 for all) included reading acuity, reading speed, mesopic and photopic contrast sensitivity (CS), mesopic and photopic glare disability (GD), and retinotopic ocular sensitivity (ROS) at all eccentricities. Conclusion. Eyes with nv-AMD undergoing intravitreal ranibizumab injections exhibit improvements in many parameters of visual function. Outcome measures other than CDVA, such as CS, GD, and ROS, should not only be considered in the design of studies investigating nv-AMD, but also in treatment and retreatment strategies for patients with the condition

Liposomal delivery of p-ialB and p-omp25 DNA vaccines improves immunogenicity but fails to provide full protection against B. melitensis challenge

BACKGROUND: We have previously demonstrated protective efficacy against B. melitensis using formulations of naked DNA vaccines encoding genes ialB and omp25. The present study was undertaken to further understand the immune response generated by the protective vaccination regimens and to evaluate cationic liposome adsorption as a delivery method to improve vaccine utility. METHODS: The protective efficacy and immunogenicity of vaccines delivered as four doses of naked DNA, a single dose of naked DNA or a single dose of DNA surface adsorbed to cationic liposomes were compared using the BALB/c murine infection model of B. melitensis. Antigen-specific T cells and antibody responses were compared between the various formulations. RESULTS: The four dose vaccination strategy was confirmed to be protective against B. melitensis challenge. The immune response elicited by the various vaccines was found to be dependent upon both the antigen and the delivery strategy, with the IalB antigen favouring CD4+ T cell priming and Omp25 antigen favouring CD8+. Delivery of the p-ialB construct as a lipoplex improved antibody generation in comparison to the equivalent quantity of naked DNA. Delivery of p-omp25 as a lipoplex altered the profile of responsive T cells from CD8+ to CD4+ dominated. Under these conditions neither candidate delivered by single dose naked DNA or lipoplex vaccination methods was able to produce a robust protective effect. CONCLUSIONS: Delivery of the p-omp25 and p-ialB DNA vaccine candidates as a lipoplex was able to enhance antibody production and effect CD4+ T cell priming, but was insufficient to promote protection from a single dose of either vaccine. The enhancement of immunogenicity by lipoplex delivery is a promising step toward improving the practicality of these two candidate vaccines, and suggests that this lipoplex formulation may be of value in situations where improvements to CD4+ responses are required. However, in the case of Brucella vaccine development it is suggested that further modifications to the candidate vaccines and delivery strategies will be required in order to deliver sustained protection