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Peroxyacetyl nitrate (PAN), an important species of photochemical smog, has received much concern for its impact on atmospheric chemistry and relation with other pollutants including ozone (O 3). This study conducted PAN measurements at the CS site (urban area) and the NQ site (suburban area) of Chongqing in summer in 2015. Maximum PAN concentrations were 12.17 (mean: 2.05 ± 1.94 ppbv) and 8.53 ppbv (mean: 0.84 ± 0.89 ppbv) at the CS and NQ sites, respectively. An observation-based box model coupled with RACM2 was applied to explore PAN formation mechanisms and its key precursors. Results showed that PAN formation was limited by both nitrogen dioxides (NO X) and volatile organic compounds (VOCs) at both sites, and NO X and nitrous acid were essential PAN precursors, especially on polluted days. For VOCs, key first-generation precursors were identified as alkenes and aromatics at the CS site (aromatics and isoprene at the NQ site). On polluted days, the relative production efficiency of PAN to O 3 enhanced more significantly at the NQ site (0.9 times) than at the CS site (0.4 times), which was related to formation/destruction reactivities of PAN and O 3. Furthermore, this study firstly explored the quantitative impacts of precursors to the relative formation of PAN to O 3 , and the results indicated that NO X predominated their relative formation at both sites. For VOCs, urban alkenes and suburban aromatics contributed to elevated PAN formation relative to O 3 , and the increase of aromatics dominated the PAN enhancement relative to O 3 during the polluted period. Image 1 • NO X and HONO were key precursors to PAN formation in urban and suburban Chongqing. • We firstly quantified impacts of precursors on the relative formation of PAN to O 3. • Relative formation of PAN to O 3 in Chongqing was most sensitive to NO X. • For VOCs, urban alkenes and suburban aromatics dominated relative PAN formation to O 3. • High RPR(PAN/O 3) on episodes at both sites were related to the increase of aromatics. [ABSTRACT FROM AUTHOR]

Background The association between CYP2D6 metabolizer status and clinical outcomes of venlafaxine was extensively investigated previously, but no widely accepted conclusion has been reached so far. To obtain a more precise estimation of the association, a systematic review by meta-analysis was conducted in the present study. Methods The PubMed, EMBASE, Cochrane Library, Chinese National Knowledge Infrastructure, Technology of Chongqing, and Wan Fang Database were searched for eligible studies up to August 2018. Results Fourteen related studies involving 1035 patients were finally included. Significant associations were found among 3 CYP2D6 phenotypes (NM, IM, and PM) and most pharmacokinetic parameters of venlafaxine. However, CYP2D6 phenotypes were not associated with Hamilton Depression Rating Scale response of venlafaxine. In addition, we also found no significant association between CYP2D6 phenotype and overall rate of adverse events. Conclusions CYP2D6 metabolizer status had significant influence on venlafaxine pharmacokinetics, but insufficient evidence demonstrated that CYP2D6 metabolizer status was associated with its therapeutic effects and overall rate of adverse events, which provided further evidence regarding the relationship between CYP2D6 metabolizer status and venlafaxine. [ABSTRACT FROM AUTHOR]