Sewage Treatment Project Design of Wuhan Huoshenshan and Leishenshan Hospitals

The Huoshenshan hospital and Leishenshan hospital are special infectious diseases hospitals that were designed to focus on the treatment of patients infected by new Coronavirus pneumonia( COVID-19). The design of sewage treatment system was "pre-disinfection contact tank + septic tank + lifting pump station( including crushed grille) + regulating tank + MBBR biochemical tank +coagulation sedimentation tank + contact disinfection tank ". MBBR process could achieve efficient removal of pollutants in sewage at low temperature. Two-stage disinfection process guaranteed 100% virus elimination. At the same time,HDPE membrane was laid under the sewage station according to the landfill standard to ensure the full collection,disinfection and discharge of rainwater and sewage. The sludge was collected and transported as hazardous waste after disinfection and dehydration. The waste gas was collected,deodorized and disinfected in a unified way,so as to realize the full collection and treatment of rainwater,sewage,sludge and waste gas. At present,the operations of the sewage stations of Huoshenshan and Leishenshan hospitals had kept stable,and the relevant effluent indexes met the design requirements. COD concentration was stable below 50 mg/L,ammonia nitrogen was stable below 2 mg/L,residual chlorine was stable near 13 mg/L. Therefore,the pollutant removal and disinfection effect were stable during the whole operation.

Discovery of Aptamers Targeting Receptor-Binding Domain of the SARS-CoV-2 Spike Glycoprotein (preprint)

The World Health Organization has declared the outbreak of a novel coronavirus (SARS-CoV-2 or 2019-nCoV) as a global pandemic. However, the mechanisms behind the coronavirus infection are not yet fully understood, nor are there any targeted treatments or vaccines. In this study, we identified high-binding-affinity aptamers targeting SARS-CoV-2 RBD, using an ACE2 competition-based aptamer selection strategy and a machine learning screening algorithm. The K d values of the optimized CoV2-RBD-1C and CoV2-RBD-4C aptamers against RBD were 5.8 nM and 19.9 nM, respectively. Simulated interaction modeling, along with competitive with experiments, suggests that two aptamers may have partially identical binding sites at ACE2 on SARS-CoV-2 RBD. These aptamers present an opportunity for generating new probes for recognition of SARS-CoV-2, and could provide assistance in the diagnosis and treatment of SARS-CoV-2 while providing a new tool for in-depth study of the mechanisms behind the coronavirus infection.