Suspected Human-to-Cat Spillover of SARS-CoV-2 Omicron Variant in South Korea.

This retrospective study reports the isolation and characterization of Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) from a household cat in South Korea. The cat, which was presented with respiratory symptoms, was identified during a retrospective analysis of samples collected between April 2021 and March 2022. Genomic sequencing revealed that the isolated virus belonged to the Omicron variant (BA.1), coinciding with its global emergence in early 2022. This case study provides evidence for the potential of direct human-to-cat transmission of the Omicron variant in South Korea during its period of widespread circulation. Our findings underscore the importance of continuous monitoring of SARS-CoV-2 in both human and animal populations to track viral evolution and potential spillover events.

Role of polyvinylpyrrolidone in the electrochemical performance of Li2MnO3 cathode for lithium-ion batteries.

While Li2MnO3 as an over-lithiated layered oxide (OLO) shows a significantly high reversible capacity of 250 mA h g-1 in lithium-ion batteries (LIBs), it has critical issues of poor cycling performance and deteriorated high rate performance. In this study, modified OLO cathode materials for improved LIB performance were obtained by heating the as-prepared OLO at different temperatures (400, 500, and 600 °C) in the presence of polyvinylpyrrolidone (PVP) under an N2 atmosphere. Compared to the as-prepared OLO, the OLO sample heated at 500 °C with PVP exhibited a high initial discharge capacity of 206 mA h g-1 and high rate capability of 111 mA h g-1 at 100 mA g-1. The superior performance of the OLO sample heated at 500 °C with PVP is attributed to an improved electronic conductivity and Li+ ionic motion, resulting from the formation of the graphitic carbon structure and increased Mn3+ ratio during the decomposition of PVP.

TiO2-coated LiCoO2 electrodes fabricated by a sputtering deposition method for lithium-ion batteries with enhanced electrochemical performance.

We fabricated lithium cobalt oxide (LiCoO2, LCO) electrodes in the absence and presence of TiO2 layers as cathodes for lithium-ion batteries (LIBs) using a sputtering deposition method under an Ar atmosphere. In particular, TiO2 coating layers on sputtered LCO electrodes were directly deposited in a layer-by-layer form with varying TiO2 sputtering times from 60 to 120 s. These sputtered electrodes were heated at 600 °C in an air atmosphere for 3 h. The thicknesses of TiO2 layers in TiO2-coated LCO electrodes were controlled from ∼2 to ∼10 nm. These TiO2-coated LCO electrodes exhibited superior electrochemical performance, i.e. high capacities (93-107 mA h g-1@0.5C), improved retention of >60% after 100 cycles, and high-rate cycling properties (64 mA h g-1@1C after 100 cycles). Such an improved performance of TiO2-coated LCO electrodes was found to be attributed to relieved volumetric expansion of LCO and protection of LCO electrodes against HF generated during cycling.