ABSTRACT
Aerosols, generated and expelled during common human physiological activities or medical procedures, become a vital carrier for the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). During non-contact intraocular pressure measurements, aerosols can be produced from the tear film on eyes and potentially convey the SARS-CoV-2 in tears, creating a high risk for eye care practitioners and patients. Herein, we numerically investigate deformation and fragmentation of the tear films with various thicknesses and surface tensions that are impinged by an air jet. Evolution of the tear films manifests several types of breakup mechanisms, including both the bag breakup and ligament breakup of tear film on the eyeball, the ligament breakup of tear film on the eyelid margin, and the sheet breakup near the eyelid margin. The sheet near the eyelid margin is critical for generating large droplets and can be formed only if the jet velocity is high enough and the film is sufficiently thick. A criterion based on Weber number and capillary number is proposed for the breakup of tear film into droplets in which three regions are used to classify the film evolution. Our results indicate that eyes with excessive tears have a greater probability of generating aerosols than eyes under normal conditions. We recommend that enhanced protections should be adopted upon measurement for the patients with watery eyes, and the time interval between two adjacent measurements for the same individual should be also prolonged during the COVID-19 pandemic. Published under an exclusive license by AIP Publishing.
ABSTRACT
COVID-19 is a major global public health challenge and difficult to control in a short time completely. To prevent the COVID-19 epidemic from continuing to worsen, global scientific research institutions have actively carried out studies on COVID-19, thereby effectively improving the prevention, monitoring, tracking, control, and treatment of the epidemic. However, the COVID-19 electronic medical records (CEMRs) among hospitals worldwide are managed independently. With privacy consideration, CEMRs cannot be made public or shared, which is not conducive to in-depth and extensive research on COVID-19 by medical research institutions. In addition, even if new research results are developed, the disclosure and sharing process is slow. To address this issue, we propose a blockchain-based medical research support platform, which can provide efficient and privacy-preserving data sharing against COVID-19. First, hospitals and medical research institutions are treated as nodes on the alliance chain, so consensus and data sharing among the nodes is achieved. Then, COVID-19 patients, doctors, and researchers need to be authenticated in various institutes. Moreover, doctors and researchers need to be registered with the Fabric certificate authority. The CEMRs for COVID-19 patients uses the blockchain's pseudonym mechanism to protect privacy. After that, doctors upload CEMRs on the alliance chain, and researchers can obtain CEMRs from the alliance chain for research. Finally, the research results will be published on the blockchain for doctors to use. The experimental results show that the read and write performance and security performance on the alliance chain meet the requirements, which can promote the wide application of scientific research results against COVID-19.