Background COVID-19 vaccine coverage in the Latinx community depends on delivery systems that overcome barriers such as institutional distrust, misinformation, and access to care. We hypothesized that a community-centered vaccination strategy that included mobilization, vaccination, and “activation” components could successfully reach an underserved Latinx population, utilizing its social networks to boost vaccination coverage. Methods Our community-academic-public health partnership, “Unidos en Salud,” utilized a theory-informed approach to design our “Motivate, Vaccinate, and Activate” COVID-19 vaccination strategy. Our strategy’s design was guided by the PRECEDE Model and sought to address and overcome predisposing, enabling, and reinforcing barriers to COVID-19 vaccination faced by Latinx individuals in San Francisco. We evaluated our prototype outdoor, “neighborhood” vaccination program located in a central commercial and transport hub in the Mission District in San Francisco, using the Reach, Effectiveness, Adoption, Implementation and Maintenance (RE-AIM) framework during a 16-week period from February 1, 2021 to May 19, 2021. Programmatic data, city-wide COVID-19 surveillance data, and a survey conducted between May 2, 2021 and May 19, 2021 among 997 vaccinated clients ≥16 years old were used in the evaluation. Results There were 20,792 COVID-19 vaccinations administered at the neighborhood site during the 16-week evaluation period. Vaccine recipients had a median age of 43 (IQR 32–56) years, 53.9% were male and 70.5% were Latinx, 14.1% white, 7.7% Asian, 2.4% Black, and 5.3% other. Latinx vaccinated clients were substantially more likely than non-Latinx clients to have an annual household income of less than $50,000 a year (76.1% vs. 33.5%), be a first-generation immigrant (60.2% vs. 30.1%), not have health insurance (47.3% vs. 16.0%), and not have access to primary care provider (62.4% vs. 36.2%). The most frequently reported reasons for choosing vaccination at the site were its neighborhood location (28.6%), easy and convenient scheduling (26.9%) and recommendation by someone they trusted (18.1%); approximately 99% reported having an overall positive experience, regardless of ethnicity. Notably, 58.3% of clients reported that they were able to get vaccinated earlier because of the neighborhood vaccination site, 98.4% of clients completed both vaccine doses, and 90.7% said that they were more likely to recommend COVID-19 vaccination to family and friends after their experience; these findings did not substantially differ according to ethnicity. There were 40.3% of vaccinated clients who said they still knew at least one unvaccinated person (64.6% knew ≥3). Among clients who received both vaccine doses (n = 729), 91.0% said that after their vaccination experience, they had personally reached out to at least one unvaccinated person they knew (61.6% reached out to ≥3) to recommend getting vaccinated; 83.0% of clients reported that one or more friends, and/or family members got vaccinated as a result of their outreach, including 18.9% who reported 6 or more persons got vaccinated as a result of their influence. Conclusions A multi-component, “Motivate, Vaccinate, and Activate” community-based strategy addressing barriers to COVID-19 vaccination for the Latinx population reached the intended population, and vaccinated individuals served as ambassadors to recruit other friends and family members to get vaccinated.

Background Maintaining retention in preexposure prophylaxis (PrEP) care among diverse patient populations will be needed to support PrEP’s efficacy. We characterized patterns of PrEP care retention in a US municipal primary care health network and examined whether missed visits, a metric of care retention that is easy to evaluate in clinic, are associated with subsequent discontinuation. Methods We included individuals on PrEP from July 2012 until August 2017 in the San Francisco Primary Care Clinics, a 15-clinic municipal health network. We categorized PrEP usage patterns as follows: early discontinuation (<90 days), later discontinuation (after ≥90 days), and continuing use at the end of follow-up. We first examined early discontinuation using adjusted Poisson regression. In patients who continued PrEP for ≥90 days, we examined factors associated with late discontinuation. Results Of the 364 individuals who started PrEP, 16% discontinued PrEP before 90 days, 46% discontinued later, and 38% were retained in care over a median 12 months of observation. Transgender women were more likely to discontinue PrEP early (adjusted risk ratio; 2.16; 95% confidence interval, 1.36–3.49), and younger users were more likely to discontinue late (0.82 per 10-year increase in age; .70–.96), as were persons who use illicit drugs (1.59; 1.02–2.47). Missed visits during use of PrEP were associated with future discontinuation (adjusted risk ratio, 1.52; 95% confidence interval, 1.14–2.03). Later year of current PrEP use was associated with both early and late discontinuation. Conclusion Diverse populations may require differentiated care to continue PrEP. Missed visits should trigger tailored interventions to maximize the impact of PrEP.

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This study uses classical molecular dynamics to simulate infinite nuclear matter and study the effect of isospin asymmetry on bulk properties such as energy per nucleon, pressure, saturation density, compressibility and symmetry energy. The simulations are performed on systems embedded in periodic boundary conditions with densities and temperatures in the ranges ρ = 0.02 to 0.2 f m −3 and T = 1, 2, 3, 4 and 5 MeV, and with isospin content of x = Z/A = 0.3, 0.4 and 0.5. The results indicate that symmetric and asymmetric matter are self-bound at some temperatures and exhibit phase transitions from a liquid phase to a liquid-gas mixture. The main effect of isospin asymmetry is found to be a reduction of the equilibrium densities, a softening of the compressibility and a disappearance of the liquid-gas phase transition. A procedure leading to the evaluation of the symmetry energy and its variation with the temperature was devised, implemented and compared to mean field theory results.

In this article, we study theoretically the properties of hematene, a new antiferromagnetic 2D material exfoliated from hematite. Hematene is not a van-der Waals material, but it can still be obtained by liquid exfoliation of hematite crystals. Its properties might be quite different from those of the bulk and to establish such differences is one of the aims of this study. A detailed study of hematene by density functional theory has been carried out to look at the electronic properties of this iron oxide material. Results show that freestanding hematene is antiferromagnetic with a magnetic moment of 4 per atom and an insulator/semiconductor with a bandgap of almost 1.0 eV. The stability of hematene is confirmed by calculating its phonon spectrum. Hematene supported on gold and stanene was also investigated: while no significant changes are found for the contact with the former, the interaction with the latter turn Hematene into a 2D ferrimagnet.

Insufficient pre-exposure prophylaxis (PrEP) laboratory monitoring could increase HIV resistance and sexually transmitted infections. We examined test-ordering in a primary care network. Providers did not order HIV testing before almost one-quarter of PrEP initiations; panel management was associated with higher testing. Effective monitoring is needed to maximize PrEP’s preventive impact.

The potential and properties of palladium hollow nanoparticles (hNPs) as a possible H storage material are explored by means of classical molecular dynamics (MD) simulations. First, we study the stability of pure Pd hNPs for different sizes and thicknesses, obtaining good agreement with experimental results for nanometer size Pd hNP. Next we add, every 100 fs, single H atoms into the NP cavity. During the first stages of the simulation, our results show hydride formation on the inner surface, similar to what has been observed in experiments on Pd surfaces and NPs. Formation of the Pd hydride decreases the absorption rate, and H gas is formed inside the cavity. The maximum H gas pressure that is reached is of 7 GPa, before fractures appear in the hNP, and consequently the hNP breaks up. We obtain a maximum H/Pd ratio of 1.21 when H is introduced only inside the cavity. However, when H is deposited both on the inside and outside surfaces, this ratio reaches 1.70, which is 25% larger than previous reports. Beyond this ratio, the hNP breaks up, and the H gas is ejected from the hNP cavity.

The irradiation of spherical gold nanoparticles (AuNPs) with nanosecond laser pulses induces shape transformations yielding nanocrystals with an inner cavity. The concentration of the stabilizing surfactant, the use of moderate pulse fluences, and the size of the irradiated AuNPs determine the efficiency of the process and the nature of the void. Hollow nanocrystals are obtained when molecules from the surrounding medium (e.g., water and organic matter derived from the surfactant) are trapped during laser pulse irradiation. These experimental observations suggest the existence of a subtle balance between the heating and cooling processes experienced by the nanocrystals, which induce their expansion and subsequent recrystallization keeping exogenous matter inside. The described approach provides valuable insight into the mechanism of interaction of pulsed nanosecond laser with AuNPs, along with interesting prospects for the development of hollow plasmonic nanoparticles with potential applications related to gas and liquid storage at the nanoscale.