Proceedings of the National Academy of Sciences of the United States of America
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Proc. Natl. Acad. Sci. U.S.A. · Nov 2021
Lessons learned from urgent computing in Europe: Tackling the COVID-19 pandemic.
PRACE (Partnership for Advanced Computing in Europe), an international not-for-profit association that brings together the five largest European supercomputing centers and involves 26 European countries, has allocated more than half a billion core hours to computer simulations to fight the COVID-19 pandemic. Alongside experiments, these simulations are a pillar of research to assess the risks of different scenarios and investigate mitigation strategies. While the world deals with the subsequent waves of the pandemic, we present a reflection on the use of urgent supercomputing for global societal challenges and crisis management.
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Proc. Natl. Acad. Sci. U.S.A. · Jun 2021
Temperature and population density influence SARS-CoV-2 transmission in the absence of nonpharmaceutical interventions.
As COVID-19 continues to spread across the world, it is increasingly important to understand the factors that influence its transmission. Seasonal variation driven by responses to changing environment has been shown to affect the transmission intensity of several coronaviruses. However, the impact of the environment on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains largely unknown, and thus seasonal variation remains a source of uncertainty in forecasts of SARS-CoV-2 transmission. ⋯ We find that policy intervention ("lockdown") and reductions in individuals' mobility are the major predictors of SARS-CoV-2 transmission rates, but, in their absence, lower temperatures and higher population densities are correlated with increased SARS-CoV-2 transmission. Our results show that summer weather cannot be considered a substitute for mitigation policies, but that lower autumn and winter temperatures may lead to an increase in transmission intensity in the absence of policy interventions or behavioral changes. We outline how this information may improve the forecasting of COVID-19, reveal its future seasonal dynamics, and inform intervention policies.
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Proc. Natl. Acad. Sci. U.S.A. · May 2021
Nanobody cocktails potently neutralize SARS-CoV-2 D614G N501Y variant and protect mice.
Neutralizing antibodies are important for immunity against SARS-CoV-2 and as therapeutics for the prevention and treatment of COVID-19. Here, we identified high-affinity nanobodies from alpacas immunized with coronavirus spike and receptor-binding domains (RBD) that disrupted RBD engagement with the human receptor angiotensin-converting enzyme 2 (ACE2) and potently neutralized SARS-CoV-2. ⋯ Prophylactic administration of either single nanobody-Fc or as mixtures reduced viral loads by up to 104-fold in mice infected with the N501Y D614G SARS-CoV-2 virus. These results suggest a role for nanobody-Fc fusions as prophylactic agents against SARS-CoV-2.
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Proc. Natl. Acad. Sci. U.S.A. · May 2021
Supporting social hierarchy is associated with White police officers' use of force.
Three studies translate social dominance theory to policing, testing the relationship between individual officers' endorsement of social hierarchies and their tendency to use force against residents. This article demonstrates a link between officer psychological factors and force. Because police are empowered to use force to maintain social order, and because White officers hold a dominant racial identity, we hypothesized social dominance orientation (SDO) would relate to force positively for White officers. ⋯ Finally, testing our hypotheses on a dataset pooled across these cities revealed a positive SDO/force relationship among White officers, and no significant SDO/force relationship among Black officers. These findings are consistent with our hypotheses and suggest a need to examine the role that maintaining social hierarchies plays in police behaviors. Future research must continue to investigate these relationships, especially with larger samples of non-White officers, and information about officers' patrol environments.
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Proc. Natl. Acad. Sci. U.S.A. · Apr 2021
Dynamic prioritization of COVID-19 vaccines when social distancing is limited for essential workers.
COVID-19 vaccines have been authorized in multiple countries, and more are under rapid development. Careful design of a vaccine prioritization strategy across sociodemographic groups is a crucial public policy challenge given that 1) vaccine supply will be constrained for the first several months of the vaccination campaign, 2) there are stark differences in transmission and severity of impacts from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) across groups, and 3) SARS-CoV-2 differs markedly from previous pandemic viruses. We assess the optimal allocation of a limited vaccine supply in the United States across groups differentiated by age and essential worker status, which constrains opportunities for social distancing. ⋯ However, depending on the objective, younger essential workers are prioritized to control spread or seniors to directly control mortality. When the objective is minimizing deaths, relative to an untargeted approach, prioritization averts deaths on a range between 20,000 (when nonpharmaceutical interventions are strong) and 300,000 (when these interventions are weak). We illustrate how optimal prioritization is sensitive to several factors, most notably, vaccine effectiveness and supply, rate of transmission, and the magnitude of initial infections.