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Objective: To investigate personal exposures to nitrogen oxides (NO X ) and nitrogen di-oxide (NO 2 ) and the influence of baseline personal characteristics, living environment and daily activity patterns of the participants on the exposures among adults over 35 in Tianjin and Shanghai., Methods: In this panel study, 91 healthy nonsmoking adults aged over 35 from Tianjin and Shanghai participated in our study. The study was conducted in summer and winter. The participants were followed for three times with an interval of at least two weeks. Only participants in Shanghai were followed once in winter because of the COVID-19 pandemic. Twenty-seven participants completed follow-up visits in both seasons. We measured their 24 h personal exposures to NO X and NO 2 and collected their baseline and time-activity information through questionnaire/diary. The linear mixed model was used to analyze the associations between potential influencing factors and personal NO X and NO 2 exposure levels., Results: There were 349 follow-up visits with valid 24 h personal NO 2 and NO X exposure measurements in the two cities. The ave-rage 24 h personal exposures to NO 2 and NO X (volume fraction) in Tianjin participants were 18.0×10 -9 and 26.2×10 -9 in summer, and 31.0×10 -9 and 54.9×10 -9 in winter, respectively; and the average 24 h personal exposures to NO 2 and NO X in Shanghai participants were 38.7×10 -9 and 100.0×10 -9 in summer, and 45.5×10 -9 and 139.2×10 -9 in winter, respectively. The results of univariate regression analysis showed that their personal NO X exposure levels were significantly associated with city, season, gender, average daily cooking times, and ambient NO 2 concentrations measured at fixed-site monitoring stations. In addition to the above factors, the personal NO X exposure levels were also significantly associated with educational level and the personal NO 2 exposure levels were also significantly associated with passive smoking, average daily home time, cooking energy type, residential distance from main traffic road, and use of kitchen ventilators. Multivariate regression analysis showed that the personal exposure levels of NO 2 and NO X were significantly lower in Tianjin than that in Shanghai, were significantly lower in summer than that in winter, and were significantly and positively associated with ambient NO 2 concentrations measured at fixed-site monitoring stations. In addition, personal NO X exposure levels were significantly lower in females than in males, and personal NO 2 exposure levels were significantly positively associated with average daily cooking times and significantly inversely associated with average daily home time. For every interquartile range ( IQR ) increase (12.7×10 -9 ) in ambient NO 2 , the personal NO 2 exposure levels increased by 27.5% (95% CI : 17.0%-38.9%), and personal NO X exposure levels increased by 16.1% (95% CI : 7.1%-25.8%)., Conclusion: Season, city and ambient NO 2 concentrations are significant influencing factors of personal exposure levels of NO 2 and NO X. At the same time, the personal exposures levels of NO 2 are also affected by lifestyle factors. Our study provides scientific evidence for making precise air pollution control decisions and reducing the exposure levels of NO X in the population.

Objective: We studied the influence of spoIIID gene deletion on the activity of cry1Ac, cry3A, cry4A and cry8E gene promoters in Bacillus thuringiensis and compared the activity among these promoters in spoIIID mutant (HD-delta SpoIIID)., Methods: We constructed 4 promoter fusions with lacZ gene and transformed them into wild-type strain HD-73 and HD-deltaSpoIIID to analyze their transcriptional activity. We constructed a spoIIID gene mutant (HD-(deltaASpoIIID with deletion of the cry1Ac-harboring native plasmid based on HD-ASpoIIID strain. We constructed four promoter fusions with crylAc gene and transformed them into HD-ASpoIIID and HD(-)-deltaSpoIIID to perform Cry protein quantization and bioassay., Results: By Beta-galactosidase assay we found that the activities of the four promoters were, in decreasing order, Pcry8E > Pcry1A > Pcry4A > Pcry3A in both HD-73 and HD-deltaSpoIIID strains. The deletion of spoIID had no effect on transcriptional activity of PcrylAc and Pcry8E. The transcriptional activity of Pcry3A in HD-deltaSpoIIID was slightly higher than that in HD-73. The transcriptional activity of Pcry4A in HD-deltaSpoIIID was decreased compared to HD-73. The Cry1Ac protein production directed by Pcry1Ac was as much as Pcry8E in HD-deltaSpoIIID and higher than that by Pcry4A and Pcry3A in accordance with the bioassay result., Conclusion: The cry8E gene promoter is the strongest promoter among four promoters in spoIIID gene mutant at transcriptional level. The Cry1 Ac protein production directed by Pcry1Ac is almost equal to that by Pcry8E.

Objective: An ion chromatographic method was developed to analyze sulfur dioxide in traditional Chinese medicine (TCM)., Method: The samples were extracted with alkaline solution and reacted with formaldehyde to form hydroxymethyl sulfonic acid. The extracts were cleaned by C18 column and SO3(2-) was determined with ion chromatography equipped with a conductance detector. In the method, AS11-HC chromatographic column was used and the mobile phase was 15 mmol x L(-1) KOH., Result: The calibration curve was in good linearity in the range of 1 to 100 microg (r =0.9992). The detection limit was 0.53 mg x kg(-1) and the average recovery was 103.7%., Conclusion: The method is simple, sensitive, precise, short-time-consuming, and the random error is smaller, which is applicable to the testing of large quantity batches of TCM.

Peptides are increasingly used as pharmaceutical agents. Many small peptides are the essential compounds in biological systems. Direct chiral separation of dipeptide derivatives using 9-(2-carbazole) ethyl chloroformate (CEOC) as the derivatizing agent by capillary electrophoresis (CE) with beta-cyclodextrin (beta-CD) and sodium deoxycholate (SDC) as chiral selectors has been developed. It has been well recognized that the combination of the binary selectors can enhance the selectivity and resolution instead of either beta-CD or SDC alone. The molar ratio of the binary chiral selectors, the buffer concentration and pH of Tris-H3PO4, organic modifier were studied and optimized. Complete chiral separations for 14 dipeptide derivatives using beta-CD and SDC as binary chiral selectors were obtained. The results indicated that each pair of D/L chiral resolution was more than 3.63, and the highest resolution for Gly-Ala was 43.14.