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The study aims to investigate the effects of delivery modalities on psychometric characteristics and student performance on cognitive tests. A first study assessed the inductive reasoning ability of 715 students under the supervision of teachers. A second study examined 731 students’ performance on the application of the control-of variables strategy in basic physics but without teacher supervision due to the COVID-19 pandemic. Rasch measurement showed that the online format fitted to the data better in the unidimensional model across two conditions. Under teacher supervision, paper-based testing was better than online testing in terms of reliability and total scores, but contradictory findings were found in turn without teacher supervision. Although measurement invariance was confirmed between two versions at item level, the differential bundle functioning analysis supported the online groups on the item bundles constructed of figure-related materials. Response time was also discussed as an advantage of technology-based assessment for test development.

Lipid nanoparticles (LNPs) are the leading technology for RNA delivery, given the success of the Pfizer/BioNTech and Moderna COVID-19 mRNA (mRNA) vaccines, and small interfering RNA (siRNA) therapies (patisiran). However, optimization of LNP process parameters and compositions for larger RNA payloads such as self-amplifying RNA (saRNA), which can have complex secondary structures, have not been carried out. Furthermore, the interactions between process parameters, critical quality attributes (CQAs), and function, such as protein expression and cellular activation, are not well understood. Here, we used two iterations of design of experiments (DoE) (definitive screening design and Box-Behnken design) to optimize saRNA formulations using the leading, FDA-approved ionizable lipids (MC3, ALC-0315, and SM-102). We observed that PEG is required to preserve the CQAs and that saRNA is more challenging to encapsulate and preserve than mRNA. We identified three formulations to minimize cellular activation, maximize cellular activation, or meet a CQA profile while maximizing protein expression. The significant parameters and design of the response surface modeling and multiple response optimization may be useful for designing formulations for a range of applications, such as vaccines or protein replacement therapies, for larger RNA cargoes.

Abstract Objective To explore whether video-based patient decision aids (VBPDAs) for cataract surgery consultation can enhance a patient’s decision-making process while upholding safety regulations during the coronavirus disease 2019 (COVID-19) pandemic. Design Single-centre consecutive case study. Participants 147 patients, with an average age of 70 years, who came in for a cataract surgery consult were enrolled in this study. Methods All patients watched part 1 of the VBPDA outlining the process of cataract surgery and the decisions involved. Patients then underwent cataract surgery consultation with an ophthalmologist. Afterward, if the patient was indicated for surgery, part 2 of the VBPDA was played. At the end of the visit, all patients completed a survey assessing the effects of COVID-19 safety precautions on their appointment. In addition, patients who had gone forward with surgery complete the Decisional Conflict Scale (DCS). Results For patients proceeding with cataract surgery, the median DCS score was 9.38 (range, 0–54.69, min–max) on a scale from 0 to 100 (low–high decisional conflict). A DCS score 25 indicates feeling unsure (n = 35, 31.53%). The DCS also can be separated into various subscales: the informed subscale (median = 8.33; min–max = 0–66.67), values subscale (16.67, 0–58.33), support subscale (8.33, 0–50.00), uncertainty subscale (8.33, 0–83.33), and effective decision subscale (0, 0–37.50). Conclusion Our study found VBPDAs to be an effective tool to enhance the patient decision-making process for cataract surgery during the COVID-19 era.

Abstract Objective Homeless and marginally housed populations experience a higher prevalence of visual impairment relative to the general population. The aim of this pilot study is to present a novel model for conducting ocular screening clinics for homeless individuals during a pandemic and to describe the status of ocular health in this population during this time. Methods In this cross-sectional study, 3 outdoor tent-based ocular screening clinics were held in a park in Toronto. Most participants were recruited from local shelters, but additional spots were allocated for homeless individuals on a drop-in basis. Prior to enrolment, each participant underwent COVID-19 screening via a questionnaire and temperature measurement. Those who screened negative received a comprehensive eye examination, including vision testing, dilated fundus examination, and autorefraction. Results Eleven individuals completed all assessments. The mean age of participants was 54.5 years, and 11 of the participants were male. Visual impairment was found in 5 individuals. Refractive error via pinhole testing was found in 1 patient. Ocular pathology in this sample was found in 4 participants. Two patients required a referral to an ophthalmologist. From a psychosocial perspective, 4 participants reported significant difficulties. Conclusions This novel tent-based ocular screening program provides a viable option for screening in a pandemic.

Background Vaccines against SARS-CoV-2 have been shown to reduce risk of infection as well as severe disease among those with breakthrough infection in adults. The latter effect is particularly important as immune evasion by Omicron variants appears to have made vaccines less effective at preventing infection. Therefore, we aimed to quantify the protection conferred by mRNA vaccination against hospitalization due to SARS-CoV-2 in adolescent and pediatric populations. Methods We retrospectively created a cohort of reported SARS-CoV-2 case records from Ontario’s Public Health Case and Contact Management Solution among those aged 4 to 17 linked to vaccination records from the COVaxON database on January 19, 2022. We used multivariable logistic regression to estimate the association between vaccination and hospitalization among SARS-CoV-2 cases prior to and during the emergence of Omicron. Results We included 62 hospitalized and 27,674 non-hospitalized SARS-CoV-2 cases, with disease onset from May 28, 2021 to December 4, 2021 (Pre-Omicron) and from December 23, 2021 to January 9, 2022 (Omicron). Among adolescents, two mRNA vaccine doses were associated with an 85% (aOR = 0.15; 95% CI: [0.04, 0.53]; p<0.01) lower likelihood of hospitalization among SARS-CoV-2 cases caused by Omicron. Among children, one mRNA vaccine dose was associated with a 79% (aOR = 0.21; 95% CI: [0.03, 0.77]; p<0.05) lower likelihood of hospitalization among SARS-CoV-2 cases caused by Omicron. The calculation of E-values, which quantifies how strong an unmeasured confounder would need to be to nullify our findings, suggest that these effects are unlikely to be explained by unmeasured confounding. Conclusions Despite immune evasion by SARS-CoV-2 variants, vaccination continues to be associated with a lower likelihood of hospitalization among adolescent and pediatric Omicron (B.1.1.529) SARS-CoV-2 cases, even when the vaccines do not prevent infection. Continued efforts are needed to increase vaccine uptake among adolescent and pediatric populations.