The rapid industrial development has led to the intermittent outbreak of pm2.5 or haze in developing countries, which has brought about great environmental issues, especially in big cities such as Beijing and New Delhi. We investigated the factors and mechanisms of haze change and present a long-term prediction model of Beijing haze episodes using time series analysis. We construct a dynamic st...

To provide some useful information about the control of air pollution in China, we studied the spatial-temporal characteristics of air pollution in China from 2001-2014. First, we drew several line charts and histograms of the Air Pollution Index (API) and Air Quality Index (AQI) of 31 capital cities and municipalities to research the distribution across different times and cities; then, we res...

Air pollution indices are commonly used to indicate the level of severity of air pollution to the public. The Pollution Standards Index (PSI) was initially established in response to a dramatic increase in the number of people suffering respiratory irritation due to the deteriorating air quality. The PSI was subsequently revised and implemented by the USEPA in 1999, and became known as the Air ...

US EPA has included sub-indices of 8-hour average O3 concentration and 24-hour average PM2.5 level into a newly-modified Air Quality Index (AQI). Calculations at air-quality monitoring stations in Taiwan show that the updated AQI system is associated with two to three times higher occurring frequency of days with AQI larger than 100 than that of the widely used Pollution Standard Index (PSI) la...

Objective The objective of the study was to analyze the effect of environmental factors on the differential expression of microRNAs in the peripheral blood of migratory and local patients in northern People's Republic of China and on clinical symptoms of local patients in northern People's Republic of China with COPD. Methods A total of 118 patients in the northern region and 8 migratory pati...

The so-calledAir Quality Index (AQI), expresses the quality of atmospheric air. The overall AQI is determined from the AQIs of some reference air pollutants, which are calculated by a transform of the respective concentrations. Concentrations of air pollutants are compositional data; they are expressed as part of mass of each pollutant in a total air volume or mass. Therefore, air pollution con...