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Objective: To examine the association between initial COVID‐19 vaccine hesitancy and subsequent vaccination among pregnant and postpartum individuals. Design: Prospective cohort. Setting: A Midwestern tertiary‐care academic medical center. Individuals completed a baseline vaccine hesitancy assessment from 22 March 2021 to 2 April 2021, with subsequent ascertainment of vaccination status at 3–6 months follow‐up. Methods: We used multivariable Poisson regression to estimate the relative risk of vaccination by baseline vaccine hesitancy status, and then characteristics associated with vaccination. Main outcome measures: Self‐report of COVID‐19 vaccination, and secondarily, consideration of COVID‐19 vaccination among those not vaccinated. Results: Of 456 individuals (93% pregnant, 7% postpartum) initially surveyed, 290 individuals (64%; 23% pregnant, 77% postpartum) provided subsequent vaccination status (median = 17 weeks). Of these 290 individuals, 40% (116/290) reported COVID‐19 vaccine hesitancy upon enrolment, of whom 52% reported subsequent vaccination at follow‐up. Few individuals transitioned during the study period from vaccine hesitant to vaccinated (10%); in comparison, 80% of those who were not vaccine hesitant were vaccinated at follow‐up (aRR 0.19, 95% CI 0.11–0.33). Among those who remained unvaccinated at follow‐up, 38% who were vaccine hesitant at baseline were considering vaccination, compared with 71% who were not vaccine hesitant (aRR 0.48, 95% CI 0.33–0.67). Individuals who were older, parous, employed and of higher educational attainment were more likely to be vaccinated, and those who identified as non‐Hispanic black, were Medicaid beneficiaries, and were still pregnant at follow‐up were less likely to be vaccinated. Conclusions: COVID‐19 vaccine hesitancy persisted over time in the peripartum period, and few individuals who reported hesitancy at baseline were later vaccinated. Interventions that address vaccine hesitancy in pregnancy are needed. COVID‐19 vaccination hesitancy among pregnant and postpartum individuals persists over time, and few of the individuals who reported hesitancy were later vaccinated. [ABSTRACT FROM AUTHOR]

A mixed elastohydrodynamic lubrication (EHL) model for a coated angular contact ball bearing is developed by coupling the influence coefficients with the unified deterministic mixed EHL model. Based on the bearing quasi‐dynamics analysis, the influences of the surface roughness, coating thickness, and boundary friction coefficient on the mixed EHL performance of the coated bearing are discussed. The results reveal that high surface root‐mean‐square roughness can be detrimental to bearing lubrication performance and increase the risk of coating failures. Coating thicknesses on the order of a few microns have a limited effect on the contact load ratio, film thickness ratio, and friction coefficient while having a significant effect on the maximum surface tensile stress and interfacial shear stress, especially for high‐friction low‐speed conditions. A low‐friction self‐lubricating coating can effectively improve the tribological performance and prolong the service life of the bearing, especially in the bad lubrication state with severe asperity contacts. [ABSTRACT FROM AUTHOR]

In this paper, the angular contact ball bearings under low‐speed and heavy‐load conditions is studied with a coupled numerical method of mixed elastohydrodynamic lubrication (EHL) and quasi‐dynamic analysis. Compared with the quasi‐dynamic analysis without consideration of the mixed lubrication characteristics, the present coupled method reveals a smaller minimum film thickness and a larger frictional coefficient in ball‐race contact interface, leading to increases in the normal contact load, slide‐to‐roll ratio, and relative sliding velocity. Effects of operation condition (eg, rotational speed) and structural parameter (eg, inner raceway curvature coefficient and initial contact angle) on the contact and lubrication performances are discussed. The results show that a larger inner raceway curvature coefficient results in a smaller average film thickness and film thickness ratio, a larger frictional coefficient, and maximum contact pressure, while the increase in the initial contact angle has an opposite effect on these parameters. [ABSTRACT FROM AUTHOR]

Objective: To examine the association between initial COVID-19 vaccine hesitancy and subsequent vaccination among pregnant and postpartum individuals., Design: Prospective cohort., Setting: A Midwestern tertiary-care academic medical center. Individuals completed a baseline vaccine hesitancy assessment from 22 March 2021 to 2 April 2021, with subsequent ascertainment of vaccination status at 3-6 months follow-up., Methods: We used multivariable Poisson regression to estimate the relative risk of vaccination by baseline vaccine hesitancy status, and then characteristics associated with vaccination., Main Outcome Measures: Self-report of COVID-19 vaccination, and secondarily, consideration of COVID-19 vaccination among those not vaccinated., Results: Of 456 individuals (93% pregnant, 7% postpartum) initially surveyed, 290 individuals (64%; 23% pregnant, 77% postpartum) provided subsequent vaccination status (median = 17 weeks). Of these 290 individuals, 40% (116/290) reported COVID-19 vaccine hesitancy upon enrolment, of whom 52% reported subsequent vaccination at follow-up. Few individuals transitioned during the study period from vaccine hesitant to vaccinated (10%); in comparison, 80% of those who were not vaccine hesitant were vaccinated at follow-up (aRR 0.19, 95% CI 0.11-0.33). Among those who remained unvaccinated at follow-up, 38% who were vaccine hesitant at baseline were considering vaccination, compared with 71% who were not vaccine hesitant (aRR 0.48, 95% CI 0.33-0.67). Individuals who were older, parous, employed and of higher educational attainment were more likely to be vaccinated, and those who identified as non-Hispanic black, were Medicaid beneficiaries, and were still pregnant at follow-up were less likely to be vaccinated., Conclusions: COVID-19 vaccine hesitancy persisted over time in the peripartum period, and few individuals who reported hesitancy at baseline were later vaccinated. Interventions that address vaccine hesitancy in pregnancy are needed., (© 2022 The Authors. BJOG: An International Journal of Obstetrics and Gynaecology published by John Wiley & Sons Ltd.)