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The TROPOMI satellite instrument plays a key role in nitrogen dioxide (NO2) monitoring on account of its unprecedented spatial resolution and stable quality of data. However, since 2019, TROPOMI operational NO2 retrieval has improved and updated in three versions (1.4, 2.2 and 2.4), with significant impact on retrieved NO2 column. Thus, studies including both TROPOMI NO2 data before and after the activation of these versions could show artificial jumps. Moreover, up to date evaluation result of TROPOMI NO2 data in current version 2.4 is not yet well documented in the literature. Therefore, in this work, we focus on evaluating TROPOMI's capability to detect NO2 under the different retrieval version conditions, by comparing with OMNO2 data and QA4ECV OMI data over China. We find a 38 % increase of tropospheric NO2 in version 1.4 due to improved FRESCO-wide cloud retrieval, and a 14 % increase in version 2.2 due to adjusted surface albedo for cloud-free scenes. We show that the upgrade to version 2.4 with new DLER surface albedo, led to an increase by 3 x 1014 molecules cm-2 of tropospheric NO2 over vegetation. Furthermore, we demonstrate that TROPOMI data shows strongest tropospheric NO2 seasonal variation compared to OMNO2 data and QA4ECV OMI data, and this seasonal effect was enhanced with the tropospheric NO2 retrieval version upgrades. Additionally, we examine for the first time the change of TROPOMI AMFs (air mass factors) in the different versions, and based on it, we arrive at a correction for the underestimation of TROPOMI NO2 column in previous versions. We also find a 33 % overestimation of NO2 reduction during the COVID-19 lockdown over China when using TROPOMI data before and after the activation of the NO2 version 1.4. [ABSTRACT FROM AUTHOR]

The political incentives of local officials affect their preferences for policy options. This study examines the impact of the convening cycle of Provincial Communist Party Congresses (PCPCs) in China on pollution emission intensity. Based on the data of 281 cities and city officials from 2003 to 2014, the present study finds strong evidence of a political pollution cycle manifesting as significant increases in pollution emission intensity before PCPCs followed by visible decreases after PCPCs. PCPCs provide city officials with strong political incentives to pursue short-term economic performance before congresses, which leads to a surge in pollution emission intensity. The difference in pollution emission intensity before and after the PCPCs reveals the existence of such political incentives. The findings suggest that a significant relationship exists between the political incentives of city officials and environmental pollution. Therefore, the effective governance of environmental pollution must involve changing the incentive structure of city officials. [ABSTRACT FROM AUTHOR]

Background: To predict the optimal functions of key aberrant genes in early-onset preeclampsia (EOPE) by using a modified network-based gene function inference method., Methods: First, differentially expressed genes (DEGs) were extracted using linear models for microarray data (LIMMA) package. Then the Spearman's rank correlation coefficient was calculated to assess co-expressed strength of each interaction between DEGs, based on which the co-expressed genes network was constructed to vividly exhibit their interlinking relationship. Subsequently, Gene ontology (GO) annotations for EOPE were collected according to known confirmed database and DEGs. Ultimately, the multifunctionality algorithm was used to extend the "guilt by association" method based on the co-expressed network, and a 3-fold cross validation was operated to evaluate the accuracy of the algorithm., Results: During the process, the GO terms, of which the area under the curve (AUC) over 0.7 were screened as the optimal gene functions for EOPE. Six functions including the ion binding and cellular response to stimulus were determined as the optimal gene functions., Conclusion: Such findings should help to better understand the pathogenesis of EOPE, so as to provide some references for clinical diagnosis and treatment in the future., Competing Interests: Conflict of Interest The authors declare that there is no conflict of interest.