Study on Spatio-Temporal Evolution Law and Driving Mechanism of PM_2.5 Concentration in Changsha–Zhuzhou–Xiangtan Urban Agglomeration

Since the 21st century, China has made many explorations to alleviate the increasingly serious air pollution problem. This study analyses the spatio-temporal evolution characteristics and future development of PM2.5 concentration in the Changsha–Zhuzhou–Xiangtan urban agglomeration from 2008 to 2019. In addition, the driving mechanism of spatial differentiation of PM2.5 concentration in this urban agglomeration was also investigated. The results were as follows. Firstly, the PM2.5 concentration showed a trend of gradual decline between 2008 and 2019. Secondly, the PM2.5 concentration distribution was high in the northwest and low in the southeast. Thirdly, PM2.5 concentration showed a strong spatial agglomeration. Fourth, except for some rural areas of Chaling County and Yanling County, the concentration of PM2.5 in other areas was very likely to continue the past trend of gradual decline. Finally, natural and meteorological conditions played a leading role in the evolution of PM2.5 concentration. The influence of socioeconomic factors is small now, but the trend is increasing. To improve air quality deeply, policymakers need to promote comprehensive control of regional air pollution by simultaneously reducing emissions and taking comprehensive treatment. They also need to strengthen supervision to prevent excessive pollution in some rural areas from worsening air quality in the surrounding areas

The advantages of multi-level omics research on stem cell-based therapies for ischemic stroke

Stem cell transplantation is a potential therapeutic strategy for ischemic stroke. However, despite many years of preclinical research, the application of stem cells is still limited to the clinical trial stage. Although stem cell therapy can be highly beneficial in promoting functional recovery, the precise mechanisms of action that are responsible for this effect have yet to be fully elucidated. Omics analysis provides us with a new perspective to investigate the physiological mechanisms and multiple functions of stem cells in ischemic stroke. Transcriptomic, proteomic, and metabolomic analyses have become important tools for discovering biomarkers and analyzing molecular changes under pathological conditions. Omics analysis could help us to identify new pathways mediated by stem cells for the treatment of ischemic stroke via stem cell therapy, thereby facilitating the translation of stem cell therapies into clinical use. In this review, we summarize the pathophysiology of ischemic stroke and discuss recent progress in the development of stem cell therapies for the treatment of ischemic stroke by applying multi-level omics. We also discuss changes in RNAs, proteins, and metabolites in the cerebral tissues and body fluids under stroke conditions and following stem cell treatment, and summarize the regulatory factors that play a key role in stem cell therapy. The exploration of stem cell therapy at the molecular level will facilitate the clinical application of stem cells and provide new treatment possibilities for the complete recovery of neurological function in patients with ischemic stroke

Study on Spatio-Temporal Evolution Law and Driving Mechanism of PM2.5 Concentration in Changsha–Zhuzhou–Xiangtan Urban Agglomeration

Since the 21st century, China has made many explorations to alleviate the increasingly serious air pollution problem. This study analyses the spatio-temporal evolution characteristics and future development of PM2.5 concentration in the Changsha–Zhuzhou–Xiangtan urban agglomeration from 2008 to 2019. In addition, the driving mechanism of spatial differentiation of PM2.5 concentration in this urban agglomeration was also investigated. The results were as follows. Firstly, the PM2.5 concentration showed a trend of gradual decline between 2008 and 2019. Secondly, the PM2.5 concentration distribution was high in the northwest and low in the southeast. Thirdly, PM2.5 concentration showed a strong spatial agglomeration. Fourth, except for some rural areas of Chaling County and Yanling County, the concentration of PM2.5 in other areas was very likely to continue the past trend of gradual decline. Finally, natural and meteorological conditions played a leading role in the evolution of PM2.5 concentration. The influence of socioeconomic factors is small now, but the trend is increasing. To improve air quality deeply, policymakers need to promote comprehensive control of regional air pollution by simultaneously reducing emissions and taking comprehensive treatment. They also need to strengthen supervision to prevent excessive pollution in some rural areas from worsening air quality in the surrounding areas