[Epidemiology, Treatment, and Epidemic Prevention and Control of the Coronavirus Disease 2019: a Review].

This review summarizes the ongoing researches regarding etiology, epidemiology, transmission dynamics, treatment, and prevention and control strategies of the coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with comparison to severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and pandemic H1N1 virus. SARS-CoV-2 may be originated from bats, and the patients and asymptomatic carriers are the source of epidemic infection. The virus can be transmitted human-to-human through droplets and close contact, and people at all ages are susceptible to this virus. The main clinical symptoms of the patients are fever and cough, accompanied with leukocytopenia and lymphocytopenia. Effective drugs have been not yet available thus far. In terms of the prevention and control strategies, vaccine development as the primary prevention should be accelerated. Regarding the secondary prevention, ongoing efforts of the infected patients and close contacts quarantine, mask wearing promotion, regular disinfection in public places should be continued. Meanwhile, rapid detection kit for serological monitoring of the virus in general population is expected so as to achieve early detection, early diagnosis, early isolation and early treatment. In addition, public health education on this disease and prevention should be enhanced so as to mitigate panic and mobilize the public to jointly combat the epidemic.

[High Resolution Emission Inventory of Greenhouse Gas and Its Characteristics in Guangdong，China].

Based on the typical city survey data and statistics of Guangdong Province， a 2018-based 3 km×3 km gridded greenhouse gas emissions inventory was developed for Guangdong Province using the combination of top-down and bottom-up emission factor methods. The inventory covered the CO2， CH4， and N2O emissions from energy， industrial processes， agriculture， land use change and forest， waste management， and indirect sources. The results showed that estimates for CO2， CH4， and N2O in Guangdong Province for the year 2018 were 8.5×108， 1.9×106， and 1.1×105 t， respectively， and 8.5×108， 4.0×107， and 3.4×107 t by equivalent carbon dioxide， totaling 9.2×108 t. CO2 was the main greenhouse gas in Guangdong Province， accounting for 92.0% of the total emissions. Energy and indirect sources were the main emission sources， accounting for 77.9% and 7.6%， respectively， totaling 85.5%. Spatial distributions illustrated that most grids were greenhouse gas emissions， whereas some others were greenhouse gas sinks； the greenhouse gas emissions were distributed mainly in the Pearl River Delta region and had certain characteristics of distribution along the road network and channels. The greenhouse gas grids of high emission were mainly the locations of high energy-consuming enterprises such as large power plants， steel mills， and cement plants.

[Seasonal Variation and Source Analysis of Water-soluble Inorganic Ions in Fine Particulate Matter in Zhengzhou].

In order to explore the characteristics of PM2.5 concentration and water-soluble inorganic ions in Zhengzhou City, a total of 170 PM2.5 samples were collected in the spring, summer, autumn, and winter seasons of 2016, with 30 days continuous sampling during each season. The mass concentration of PM2.5 was analyzed gravimetrically, water-soluble inorganic ions were determined by ion chromatography, and principle component analysis was employed for source apportionment. The results showed that the mass concentration of PM2.5 was 150.72µg·m-3 during the sampling period. The mass concentration was highest in winter and lowest in summer, and that of autumn is higher was higher than that of spring. The ions SO42-, NO3-, and NH4+ were the major WSIs found in PM2.5, accounting for 92.55%, 92.94%, 93.06%, and 93.15% of the total amount of the seven ions found in spring, summer, autumn, and winter, respectively. The anion-to-cation ratio was 0.886, which indicated that PM2.5 was slightly alkaline in Zhengzhou. Secondary inorganic species, including NH4+, NO3-, and SO42- were the major components of the water-soluble ions. These ions most likely existed in the form of NH4NO3 and (NH4)2SO4 during spring and summer, while they were present as NH4NO3, (NH4)2SO4 and NH4HSO4 in autumn. In addition to these three forms, NH4Cl or other forms may exist in winter. Industrial emissions, combustion, secondary transformation, soil, and construction dust were the major sources of the water-soluble ions in PM2.5.

[Interannual Variation of Metal Elements and Water-Soluble Ions in PM2.5 During Wintertime in Xinxiang and Their Source Apportionment].

To study the interannual variations of chemical composition and source apportionment, a field campaign was carried out to collect the PM2.5 temperance sample during the winter of 2015 and the winter of 2016 in Xinxiang urban areas. PM2.5 mass concentration, metal elements, and the water-soluble ions were determined and meteorological factors were recorded simultaneously. The results showed that the daily mean concentrations of PM2.5 indicated serious pollution with values of 226 µg·m-3 and 224 µg·m-3 in 2015 and 2016, respectively. The Cd and Pb elements in PM2.5 were significantly enriched, with EF more than 1000. However, compared with 2015, the enrichment effect of most metal elements showed a trend of decrease in 2016. The water-soluble ions were mainly composed of SO42-, NO3-, and NH4+. The results showed a trade-off effect between metal elements and water-soluble ions in the two study periods. The results of PCA and PMF analyses show that there were four main emission sources in Xinxiang city in winter, namely dust, secondary source, industrial source, and fossil fuel combustion source. Moreover, the main sources of PM2.5 was the mixed source of soil and building dust and secondary aerosol pollution, with contributions of 37.46% and 34.94% in the winters of 2015 and 2016, respectively.