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The past decade has witnessed remarkable economic development, marked by rapid industrialization and urbanization across Asian regions. This surge in economic activity has led to significant emissions, resulting in alarming levels of air pollution. Our study comprehensively assessed the spatial and temporal trends of key pollutants, namely nitrogen dioxide (NO2), sulfur dioxide (SO2), and aerosol (using aerosol optical depth (AOD) at 550 nm as an indicator), from 2011 to 2021. The data sources utilized include OMI onboard the Aura satellite for NO2 and SO2, as well as MODIS onboard Terra and Aqua satellites for AOD. The results from spatial and temporal trend analyses of the three parameters show that there is a clear declining trend over China and Republic of Korea (e.g., NO2 is declining with an overall rate of −7.8 × 1012 molecules/cm2/year over China) due to the strict implementation of air pollution control policies. However, it is essential to note that both countries still grapple with substantial pollution levels, with proportions exceeding 0.5, indicating that air quality is improving but has not yet reached a safe threshold. In contrast, South Asian regions, including Bangladesh, Pakistan, and India, are experiencing an increasing trend (e.g., NO2 is increasing with an overall rate of 1.2 × 1012 molecules/cm2/year in Bangladesh), primarily due to the lack of rigorous air pollution control policies. The average emissions of NO2 and SO2 were remarkably higher in winter than in summer. Notably, the identified hotspots are statistically significant and predominantly coincide with densely populated areas, such as the North China Plain (NCP). Furthermore, this study underscores the pivotal role of sector-wise emissions in air quality monitoring and improvement. Different cities are primarily influenced by emissions from specific sectors, emphasizing the need for targeted pollution control measures. The findings presented in this research contribute valuable insights to the air quality monitoring and improvement efforts in East and South Asian regions. [ABSTRACT FROM AUTHOR]

South East and East Asia are regions which have undergone rapid economic development, contributing a significant amount of urban and biomass burning emissions. While the connections between emissions, deposition, and impacts on the Earth System are theoretically understood, they are observationally and ill-constrained, especially with respect to the effects of a changing climate and the Monsoon. This work shows the results of a new classification scheme and Asian-Wide monthly wet deposition product based upon 16 years of surface wet deposition observations and remotely sensed trace gas and precipitation measurements throughout South East and East Asia. Specific information corresponding to underlying driving and physical processes including in-situ processing, long-range transport, and local emission sources are all considered. Scientific findings are made specifically with respect to the increased impacts of urban-scale change, long-range transport, and enhanced deposition under moderate to low precipitation conditions. Previously accepted definitions of clean and polluted areas are challenged and updated based upon more detailed analysis of the observed physical and chemical relationships and simple models. The spatial and temporal distribution of the resulting modeled wet deposition is shown to impact the oceans more significantly, and regions of land not previously thought to be heavily impacted. • Using wet deposition, NO 2 and precipitation to develop new classification schemes. • A significant relationship was found between wet deposition, precipitation and NO 2. • Providing deep insights into wet deposition at no current observation areas. [ABSTRACT FROM AUTHOR]

Eleutherococcus senticosus , a medicinal and edible plant recognized historically in East Asia, is characterized by a rich composition of saponins and other biologically active ingredients. In this study, 11 cytosine-5 DNA methyltransferases (C5-MTase) and 6 demethylases (dMTase) genes were identified within the genome of E. senticosus. Specifically, two major EsC5-MTases (EsMET1a and EsCMT3b) and two EsdMTases (EsROS1a and EsDME1) were screened through correlation analysis, examining the relationship between their gene expression levels and DNA methylation ratio within E. senticosus genome. Promoter function analysis revealed that the expression of these four prominent genes was regulated by abiotic stresses such as drought and light. In vitro catalytic validation demonstrated the functionality of Es MET1a, Es CMT3b, Es ROS1a, and Es DME1 proteins in modifying DNA methylation patterns of key enzyme genes associated with saponin synthesis in E. senticosus. Additionally, transient in vivo overexpression of the four central genes could alter the saponin content by modulating the DNA methylation levels and secondary metabolic processes in E. senticosus. Molecular docking studies further elucidated the possible mechanism of DNA methylation and demethylation catalyzed by these four primary proteins. [Display omitted] • EsC5-MTase and EsdMTase of Eleutherococcus senticosus were identified. • EsC5-MTase and EsdMTase that play a major role were screened out. • Expression control factors of the effect EsC5-MTase and EsdMTase were clarified. • The function and working mechanism of EsC5-MTase and EsdMTase are explained. [ABSTRACT FROM AUTHOR]