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Background: The COVID-19 pandemic has affected the world deeply, with more than 14,000,000 people infected and nearly 600,000 deaths. This review aimed to summarize the epidemiologic traits, clinical spectrum, CT results and laboratory findings of the COVID-19 pandemic. Methods: We scoped for relevant literatures published during 1st December 2019 to 16th July 2020 based on three databases using English and Chinese languages. We reviewed and analyzed the relevant outcomes. Results: The COVID-19 pandemic was found to have a higher transmission rate compared to SARS and MERS and involved 4 stages of evolution. The basic reproduction number (R 0) is 3.32 (95% CI:3.24-3.39), the incubation period was 5.24 days (95% CI:3.97-6.50, 5 studies) on average, and the average time for symptoms onset varied by countries. Common clinical spectrums identified included fever (38.1-39.0°C), cough and fatigue, with Acute Respiratory Distress Syndrome (ARDS) being the most common complication reported. Body temperatures above 39.0°C, dyspnea, and anorexia were more common symptoms in severe patients. Aged over 65 years old, having co-morbidities, and developing complications were the commonest high-risk factors associated with severe conditions. Leucopenia and lymphopenia were the most common signs of infection while liver and kidney damage were rare but may cause bad outcomes for patients. The bilateral, multifocal Ground-Glass Opacification (GGO) on peripheral, and the consolidative pulmonary opacity were the most frequent CT results and the tendency of mortality rates differed by region. Conclusions: We provided a bird's-eye view of the COVID-19 during the current pandemic, which will help better understanding the key traits of the disease. The findings could be used for disease's future research, control and prevention.

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Boron-containing electrolyte additives have been successfully used to improve the cyclability for Li-rich layered oxide, a hopeful cathode of high energy density lithium ion battery, but available mechanisms on their contribution are diversified. In this paper, we provide evidence to confirm the mechanism that Li-rich layered oxide is protected by a solid electrolyte interface (SEI) layer derived from boron-containing electrolyte additives. Triethyl borate (TEB), a simple boron-containing molecule, is selected as the electrolyte additive, and a representative Li-rich layered oxide, Li[Li 0.2 Mn 0.54 Ni 0.13 Co 0.13 ]O 2 , is synthesized for understanding the interfacial properties between the oxide and the electrolyte through physical and electrochemical characterizations. Cyclability tests display that the as-prepared oxide exhibits a fast capacity decrease in the standard electrolyte, 1.0 M LiPF 6 , in a mixed carbonate solvent of ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), and ethylene carbonate (EC) (EMC/DMC/EC = 5/2/3, in weight), with only 30% capacity retention after 150 cycles at 0.5 C (1 C = 250 mAh g −1 ), which can be improved to 79% when 3% TEB is introduced. Physical characterizations demonstrate that the as-prepared oxide suffers a severe structural destruction accompanied by thick deposits from electrolyte decomposition products, but the crystal structure of the oxide is well protected by a uniform solid electrolyte interface (SEI) layer formed from the preferential oxidation of TEB.

Background Evaluating whether an infectious disease has reached a turning point is important for planning additional intervention efforts. This study aimed to analyze the changing patterns and the tempo-geographic features of the COVID-19 epidemic, to provide further evidence for real-time responses. Methods Daily data on COVID-2019 cases between 31st Dec. 2019 and 26th Feb. 2020 were collected and analyzed for Hubei and non-Hubei regions. Observed trends for new and cumulative cases were analyzed through joint-point regressions. Spatial analysis was applied to show the geographic distribution and changing pattern of the epidemic. Results By 26th Feb. 2020, 78,630 confirmed COVID-19 cases had been reported in China. In Hubei, an increasing trend (slope=221) was observed for new cases between 24th Jan. and February 7th Feb. 2020, after which a decline commenced (slope=-868). However, as the diagnosis criteria changed, a sudden increase (slope=5530) was observed on 12th Feb., which sharply decreased afterward (slope=-4898). In non-Hubei regions, the number of new cases increased from 20th Jan. to 3rd Feb. and started to decline afterward (slope=-53). The spatial analysis identified Chongqing, Guangzhou, Shenzhen, Changsha, Nanchang, Wenzhou, Shanghai, Xinyang, Jining, and Beijing as the hotspots outside of Hubei province in China. Conclusion and relevance The joint-point regression analysis indicated that the epidemic might have been under control in China, especially for regions outside of Hubei province. Further improvement in the response strategies based on these new patterns is needed.

The capacity fading of layered lithium-rich oxide (Li1.2Mn0.54Ni0.13Co0.13O2, LLO) cathodes greatly hinders their practical application in next generation lithium ion batteries.