Highlights d AI system that can diagnose COVID-19 pneumonia using CT scans d Prediction of progression to critical illness d Potential to improve performance of junior radiologists to the senior level d Can assist evaluation of drug treatment effects with CT quantification

It was recently brought to our attention that our paper was missing information regarding when the patient chest computed tomography (CT) scans were obtained and that there were some discrepancies in the clinical metadata, associated with the very large image dataset, that we made publicly available through the China National Center for Bioinformation (http://ncov-ai.big.ac.cn/ download?lang=en). All of the chest CT and clinical metadata used in our prognostic analysis were collected from patients at the time of hospital admission, and we have now added this statement to the STAR Methods section of our paper. We believe that the errors in the clinical metadata were introduced when the chest CT images, clinical metadata, and codes were transferred to the web server, and we have now corrected the errors manually. Although these corrections do not alter any of the conclusions made in the paper, we do apologize for these errors and any confusion that they may have caused.

We propose a model of evolutionary snowdrift game with N -person interactions and study the effects of multi-person interactions on the emergence of cooperation. An exact N -th-order equation for the equilibrium density of cooperators x * is derived for a well-mixed population using the approach of replicator dynamics. The results show that the extent of cooperation drops with increasing cost-to-benefit ratio and the number N of interaction persons in a group, with x * ∼ 1/N for large N . An algorithm for numerical simulations is constructed for the model. The simulation results are in good agreements with theoretical results of the replicator dynamics.

Exact analytic expression for obtaining the surface plasmon (SP) dispersion relations in a system consisting of a thin metallic film sandwiched between a linear dielectric and a nonlinear dielectric of arbitrary nonlinearity is derived, based on a generalized first integral approach. The changes in SP dispersion relations on film thicknesses and nonlinearity are studied by model calculations. The thick-film limit generalizes previous results on metal/Kerr-type nonlinear interface to arbitrary nonlinearity. An analytic expression is obtained for the limiting SP frequency at large wave vectors with previous result recovered as a special case.