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Coronavirus disease 2019 (COVID-19) has been highly epidemic in China since January 2020. Rapid detection of the causative agent, severe acute respiratory coronavirus-2 (SARS-CoV-2), is very important due to its high rate of infectivity. This study aimed to clarify the epidemiology and clinical characteristics of COVID-19 outside of Hubei province, China, and to optimize screening strategies for COVID-19 in attempts to contain spread of the virus. This retrospective study included all confirmed cases of COVID-19 in Hunan Provincial People's Hospital (Changsha, China) between January 22 and February 15, 2020. All cases were detected using a real-time reverse transcription polymerase chain reaction assay. The epidemiology and clinical characteristic of these cases were investigated according to outcome in attempts to optimize screening strategies for COVID-19. There were 24 confirmed cases of COVID-19 in the fever outpatient department of Hunan Provincial People's Hospital. Three patients were asymptomatic, and 3 exhibited mild and 3 moderate disease. There was a family cluster phenomenon. Individuals with COVID-19 can be asymptomatic or exhibit mild manifestations of disease. Close monitoring and an optimized screening strategy for COVID-19 could help deter spread of the virus. [ABSTRACT FROM AUTHOR]

The selective adsorption of palladium from wastewater is a feasible solution to solving palladium pollution and resource scarcity. Because traditional solvent extraction methods often involve the use of considerable amounts of organic solvents, research is focused on investigating adsorption techniques that can selectively remove palladium from wastewater. In this paper, the magnetic composite Fe 3 O 4 @MnO 2 @ZIF-67 was synthesized and its performance for the adsorption of Pd(II) in acidic water was investigated. Fe 3 O 4 @MnO 2 @ZIF-67 was characterized by various analytical methods such as TEM, SEM, EDS, BET, XRD, FTIR, zeta potential analysis, VSM, and TGA. The effects of palladium ion concentration, contact time, pH, and temperature on adsorption were evaluated. The kinetics were shown to follow the pseudo-second-order kinetic model and Elovich model, and the rate-limiting step was chemisorption. Thermodynamic studies showed that increasing the temperature promoted the adsorption of Pd(II), and the maximum uptake capacity of Fe 3 O 4 @MnO 2 @ZIF-67 for Pd(II) was 531.91 mg g−1. Interestingly, Fe 3 O 4 @MnO 2 @ZIF-67 exhibited superior selectivity for Pd(II) in the presence of Ir(IV), Pt(IV), and Rh(III). The adsorbent can be used repeatedly for selective adsorption of palladium. Even at the fifth cycle, the uptake rate of Pd(II) remained as high as 83.1%, and it showed a favorable adsorption capacity and selectivity for Pd(II) in real metallurgical wastewater. The adsorption mechanism was analyzed by SEM, FTIR, XRD, XPS, and DFT calculations, which indicated that electrostatic interactions and coordination with nitrogen-containing groups were involved. Fe 3 O 4 @MnO 2 @ZIF-67 is a promising adsorbent for the efficient adsorption and selective separation of palladium ions. [Display omitted] • A novel hydrangea-like super composite Fe 3 O 4 @MnO 2 @ZIF-67 was synthesized. • The maximum uptake capacity of Fe 3 O 4 @MnO 2 @ZIF-67 for Pd(II) is as high as 531.91 mg g−1. • Adsorbent exhibited superior selectivity for Pd(II) in actual metallurgical wastewater. • Electrostatic and coordination interactions are involved in the selective adsorption of Pd(II) by FMZ-67. [ABSTRACT FROM AUTHOR]