ABSTRACT
Background Public places are frequently polluted by cigarette smoking, and there is a lack of accurate, real-time, and intelligent monitoring technology to identify smoking behavior. It is necessary to develop a tool to identify cigarette smoking behavior in public places for more efficient control of cigarette smoking and better indoor air quality. Objective To construct a model for recognizing cigarette smoking behavior based on real-time indoor concentrations of PM2.5 in public places. Methods Real-time indoor PM2.5 concentrations were measured for at least 7 continuous days in 10 arbitrarily selected places (6 public service providers and and 4 office or other places) from Oct. to Nov. 2022 in Pudong New Area, Shanghai. Indoor nicotine concentrations were monitored with passive samplers simultaneously. Outdoor PM2.5 concentration data were obtained from three municipal environmental monitoring stations which were nearest to each monitoring point during the same period. Mann-Whitney U test was used to compare indoor and outdoor means of PM2.5 concentrations, and Spearman rank correlation was used to analyze indoor PM2.5 and nicotine concentrations. An interactive plot and a random forest model was applied to examine the association between video observation validated indoor smoking behavior and real-time indoor PM2.5 concentrations in an Internet cafe. Results The average indoor PM2.5 concentration in the places providing public services [(97.5±149.3) µg·m−3] was significantly higher than that in office and other places [(19.8±12.2) µg·m−3] (P=0.011). The indoor/outdoor ratio (I/O ratio) of PM2.5 concentration in the public service providers ranged from 1.1 to 19.0. Furthermore, the indoor PM2.5 concentrations in the 10 public places were significantly correlated with the nicotine concentrations (rs=0.969, P<0.001). Among them, the top 3 highly polluted places were Internet cafes, chess and card rooms, and KTV. The results of random forest modeling showed that, for synchronous real-time PM2.5 concentration, the area under the curve (AUC) was 0.66, while for PM2.5 concentration at a lag of 4 min after the incidence of smoking behavior, the AUC increased to 0.72. Conclusion The indoor PM2.5 concentrations in public places are highly correlated with smoking behavior. Based on real-time indoor PM2.5 monitoring, a preliminary recognition model for smoking behavior is constructed with acceptable accuracy, indicating its potential values applied in smoking control and management in public places.
ABSTRACT
In the past decades, people's work and life styles have dramatically changed during the rapid economic development and urbanization in China. A national survey reported that Chinese adults spend an average of 81% of daily time in indoor environment. Exposure to indoor air pollution plays key roles for human health but is likely to be neglected due on the relatively lower concentration levels and lower awareness among common people. Till now, published studies focus more on the pollution levels or the toxicological effects of indoor air pollutants but there is a lack of disease burden assessment attributable to indoor air pollution. In this review, several international studies were introduced on the disease burden estimation attributable to indoor air pollution, as well as the estimation methods. The current situation of national study was also reviewed. The strengths and limitations of the representative international studies were discussed. This review is helpful in providing data to guide the research on disease burden assessment attributable to indoor air pollution in China, and further helps to prioritize the indoor air pollution control based on disease burden ranking among pollutants and motivate public policies to protect the public health.
ABSTRACT
Protease inhibitors, which are widely distributed in all types of life forms, are generally considered to be one of the most abundant proteins and a defense mechanism. A protease inhibitor from tartary buckwheat seeds (TBTI-Ⅱ ), with specific trypsin-inhibitory activity, was obtained by Resource Q anion-exchange chromatography and Superdex G 75 gel filtration. SDS-PAGE analysis indicated that the approximate molecular weight was 9.0 kD. Amino-acid analysis showed that the TBTI- Ⅱ was composed of 80 amino-acid residues with a high content of glutamate, aspartate and arginine. The inhibitor had high thermostability and retained 67.6% of its activity after heating at 100℃ for 10 min. The inhibition constant Ki was determined to be 1.01× 10-4 mol/L. It was demonstrated that the inhibitor was able to have an effect on the growth of cotton bollworm larva, after being fed with the artificial diets mixed with the target inhibitor. The present study indicates that the trypsin inhibitor from tartary buckwheat seeds could be a new potential anti-insect factor.