141 results on '"Su, Wenjing"'
Search Results
2. Morphology, immunohistochemistry characteristics, and clinical presentation of microcystic urothelial carcinoma: a series of 10 cases
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Su, Wenjing, Sui, Wenwen, Cheng, Xiankui, Zong, Yuanyuan, Qin, Yejun, and Cui, Fengyun
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- 2023
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3. Identification and immune features of cuproptosis-related molecular clusters in polycystic ovary syndrome
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Su, Zhe, Su, Wenjing, Li, Chenglong, Ding, Peihui, and Wang, Yanlin
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- 2023
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4. High Spatial Resolution Ozone Profiles Retrieved from the First Chinese Ultraviolet–Visible Hyperspectral Satellite Instrument
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Zhao, Fei, Liu, Cheng, Hu, Qihou, Xia, Congzi, Zhang, Chengxin, and Su, Wenjing
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- 2024
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5. Research on habitat quality assessment and decision-making based on Semi-supervised Ensemble Learning method—Daxia River Basin, China
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Wang, Shengwei, Chen, Hongquan, Su, Wenjing, Cui, Shuohao, Xu, Yurong, and Zhou, Zhiqiang
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- 2023
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6. Satellite unravels recent changes in atmospheric nitrogen oxides emissions from global ocean shipping
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Wang, Xiaohan, Zhang, Chengxin, Gao, Yuanyun, Ji, Xiangguang, Su, Wenjing, and Liu, Cheng
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- 2023
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7. Battery-less long-range wireless fluidic sensing system using flexible additive manufacturing ambient energy harvester and microfluidics
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Lin, Tong-Hong, Su, Wenjing, Cui, Yepu, Bahr, Ryan, and Tentzeris, Manos M.
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- 2024
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8. Unexpected HCHO transnational transport: influence on the temporal and spatial distribution of HCHO in Tibet from 2013 to 2021 based on satellite
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Xu, Yizhou, Su, Wenjing, Hu, Qihou, Zhang, Chengxin, Javed, Zeeshan, Tian, Yuan, Hou, Hongri, and Liu, Cheng
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- 2024
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9. Insights into the inhibition of protospacer integration via direct interaction between Cas2 and AcrVA5
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Bi, Mingfang, Su, Wenjing, Li, Jiafu, and Mo, Xiaobing
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- 2024
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10. Zero-waste utilization and conversion of shrimp shell by mechanochemical method
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Su, Wenjing, Xu, Wenhao, Polyakov, Nikolay E., Dushkin, Alexandr V., Qiao, Pei, and Su, Weike
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- 2023
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11. A new strategy for the preparation of highly stable and high-capacity electrodes for green electrochemical extraction of lithium
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Zhang, Junyan, Su, Wenjing, Yi, Bin, Guo, Yafei, Deng, Tianlong, and Yu, Xiaoping
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- 2023
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12. Effect of Tremella fuciformis polysaccharide on the stalling and flavor of tteok during storage
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Fan, Hongxiu, Liu, Hongcheng, Li, Wenyi, Su, Wenjing, Wang, Dawei, Zhang, Shanshan, Liu, Tingting, and Zhang, Yanrong
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- 2023
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13. circPDE5A regulates prostate cancer metastasis via controlling WTAP-dependent N6-methyladenisine methylation of EIF3C mRNA
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Ding, Lifeng, Wang, Ruyue, Zheng, Qiming, Shen, Danyang, Wang, Huan, Lu, Zeyi, Luo, Wenqin, Xie, Haiyun, Ren, Liangliang, Jiang, Minxiao, Yu, Chenhao, Zhou, Zhenwei, Lin, Yudong, Lu, Haohua, Xue, Dingwei, Su, Wenjing, Xia, Liqun, Neuhaus, Jochen, Cheng, Sheng, and Li, Gonghui
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- 2022
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14. METTL1 drives tumor progression of bladder cancer via degrading ATF3 mRNA in an m7G-modified miR-760-dependent manner
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Xie, Haiyun, Wang, Mingchao, Yu, Haifeng, Wang, Huan, Ding, Lifeng, Wang, Ruyue, Luo, Wenqin, Lu, Zeyi, Zheng, Qiming, Ren, Liangliang, Zhou, Zhenwei, Su, Wenjing, Xia, Liqun, and Li, Gonghui
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- 2022
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15. First Chinese ultraviolet–visible hyperspectral satellite instrument implicating global air quality during the COVID-19 pandemic in early 2020
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Liu, Cheng, Hu, Qihou, Zhang, Chengxin, Xia, Congzi, Yin, Hao, Su, Wenjing, Wang, Xiaohan, Xu, Yizhou, and Zhang, Zhiguo
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- 2022
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16. Ureteral tumor with morphological features analogous to phyllodes tumor: a unique case with concomitant urothelial carcinoma
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Zhou, Wei, Dang, Linlin, Chong, Chuangang, Cheng, Xiankui, Qin, Yejun, and Su, Wenjing
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- 2022
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17. Interpretation of spatial and temporal changes and drivers of ecological source regions based on LightGBM-SHAP.
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Wang, Shengwei, Chen, Hongquan, Guo, Yu lin, Su, Wenjing, Xu, Yurong, Cui, Shuohao, and Zhou, Zhiqiang
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ECOLOGICAL regions ,SOIL conservation ,WATERSHEDS ,LAND title registration & transfer ,RAINFALL ,LAND cover - Abstract
Ecological source areas play a pivotal role in nature preservation and soil conservation. These areas are critical in optimizing land-use patterns and fostering the establishment facilitating the establishment of protected ecological source areas. In this study, two types of state layers of ecological source area change were extracted based on land cover data and integrated with an intelligent algorithm to analyze the role of ecological factors contributing to land change. Recommendations are proposed to enhance the optimization of the ecological spatial pattern within the Yellow River Basin. The results indicate key findings: (1) The ecological source areas in the Daxia River Basin experienced Fluctuations between 1990 and 2020 due to the interconversion of grassland and unused land. The change was relatively smooth during 1990–2000, with the ecological source areas increasing slightly by 16.016 km
2 . From 2000 to 2010, the proportion of unutilized land transferred to grassland was 6.3%, which is significantly higher than the annual transfer average of 1.6%. This is mainly due to the ecological protection measures in the cities of Linxia and Hezuo. Between 2010 and 2020, economic construction resulted in the loss of grassland, and the percentage of grassland turned out was 7.3%, which was significantly higher than the annual average of 1.8%. (2) In the Daxia River Basin, rainfall, sunlight intensity, temperature, and elevation had a greater impact on land change during the period from 1990 to 2020, with contributions of −0.4, 0.09, 0.08, and −0.26, respectively. [ABSTRACT FROM AUTHOR]- Published
- 2024
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18. Evaluating the feasibility of formaldehyde derived from hyperspectral remote sensing as a proxy for volatile organic compounds
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Hong, Qianqian, Liu, Cheng, Hu, Qihou, Zhang, Yanli, Xing, Chengzhi, Su, Wenjing, Ji, Xiangguang, and Xiao, Shaoxuan
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- 2021
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19. Dapagliflozin Improves Angiogenesis after Hindlimb Ischemia through the PI3K-Akt-eNOS Pathway.
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Han, Li, Ye, Guoxin, Su, Wenjing, Zhu, Yuankang, Wu, Wenqi, Hao, Liangshi, Gao, Jing, Li, Zhen, Liu, Fang, and Duan, Junli
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NEOVASCULARIZATION ,VASCULAR endothelial growth factors ,DAPAGLIFLOZIN ,HINDLIMB ,PERIPHERAL vascular diseases ,LABORATORY rats ,SODIUM-glucose cotransporters - Abstract
Recently, the vascular protective effect of anti-diabetic agents has been receiving much attention. Sodium glucose cotransporter 2 (SGLT2) inhibitors had demonstrated reductions in cardiovascular (CV) events. However, the therapeutic effect of dapagliflozin on angiogenesis in peripheral arterial disease was unclear. This study aimed to explore the effect and mechanism of dapagliflozin on angiogenesis after hindlimb ischemia. We first evaluated the effect of dapagliflozin on post-ischemic angiogenesis in the hindlimbs of rats. Laser doppler imaging was used to detect the hindlimb blood perfusion. In addition, we used immunohistochemistry to detect the density of new capillaries after ischemia. The relevant signaling pathways of dapagliflozin affecting post-ischemic angiogenesis were screened through phosphoproteomic detection, and then the mechanism of dapagliflozin affecting post-ischemic angiogenesis was verified at the level of human umbilical vein endothelial cells (HUVECs). After subjection to excision of the left femoral artery, all rats were randomly distributed into two groups: the dapagliflozin group (left femoral artery resection, receiving intragastric feeding with dapagliflozin (1 mg/kg/d), for 21 consecutive days) and the model group, that is, the positive control group (left femoral artery resection, receiving intragastric feeding with citric acid–sodium citrate buffer solution (1 mg/kg/d), for 21 consecutive days). In addition, the control group, that is the negative control group (without left femoral artery resection, receiving intragastric feeding with citric acid–sodium citrate buffer solution (1 mg/kg/d), for 21 consecutive days) was added. At day 21 post-surgery, the dapagliflozin-treatment group had the greatest blood perfusion, accompanied by elevated capillary density. The results showed that dapagliflozin could promote angiogenesis after hindlimb ischemia. Then, the ischemic hindlimb adductor-muscle tissue samples from three rats of model group and dapagliflozin group were taken for phosphoproteomic testing. The results showed that the PI3K-Akt-eNOS signaling pathway was closely related to the effect of dapagliflozin on post-ischemic angiogenesis. Our study intended to verify this mechanism from the perspective of endothelial cells. In vitro, dapagliflozin enhanced the tube formation, migration, and proliferation of HUVECs under ischemic and hypoxic conditions. Additionally, the dapagliflozin administration upregulated the expression of angiogenic factors phosphorylated Akt (p-Akt) and phosphorylated endothelial nitric oxide synthase (p-eNOS), as well as vascular endothelial growth factor A (VEGFA), both in vivo and in vitro. These benefits could be blocked by either phosphoinositide 3-kinase (PI3K) or eNOS inhibitor. dapagliflozin could promote angiogenesis after ischemia. This effect might be achieved by promoting the activation of the PI3K-Akt-eNOS signaling pathway. This study provided a new perspective, new ideas, and a theoretical basis for the treatment of peripheral arterial disease. [ABSTRACT FROM AUTHOR]
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- 2024
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20. NMR Study of Water-Soluble Carotenoid Crocin: Formation of Mixed Micelles, Interaction with Lipid Membrane and Antioxidant Activity.
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Su, Wenjing, Mastova, Anna V., Ul'yanova, Maya A., Kononova, Polina A., Selyutina, Olga Yu., Evseenko, Veronika I., Meteleva, Elizaveta S., Dushkin, Alexander V., Su, Weike, and Polyakov, Nikolay E.
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MEMBRANE lipids , *CROCIN , *MOLECULAR dynamics , *DRUG delivery systems , *LINOLEIC acid , *MICELLES - Abstract
Crocin is a unique water-soluble carotenoid found in crocus and gardenia flowers. Crocin has been shown to have a variety of pharmacological activities, such as antioxidant, anti-cancer, memory improvement, antidepressant, anti-ischemia, blood pressure lowering and aphrodisiac, gene protection and detoxification activities. Due to their amphiphilicity, crocin molecules form concentration-dependent self-associates (micelles) in a water solution. In the present study, using various NMR techniques (T2 relaxation and selective gradient NOESY), we have demonstrated that crocin forms mixed micelles with water-soluble drug delivery system glycyrrhizin and linoleic acid molecules. Note, that the spin–spin T2 relaxation time and NOESY spectroscopy are very sensitive to intermolecular interactions and molecular diffusion mobility. The second purpose of this work was the elucidation of the interaction of crocin with a model lipid membrane using NMR techniques and a molecular dynamics simulation and its effects on lipid oxidation. It was shown that the crocin molecule is located near the surface of the lipid bilayer and effectively protects lipids from oxidation by peroxyl radicals. The role of glycyrrhizin and vitamin C in metal-induced lipid oxidation was also elucidated. The results of this study may be useful for expanding the field of application of crocin in medicine and in the food industry. [ABSTRACT FROM AUTHOR]
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- 2024
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21. Estimation of winter time NOx emissions in Hefei, a typical inland city of China, using mobile MAX-DOAS observations
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Tan, Wei, Zhao, Shaohua, Liu, Cheng, Chan, Ka Lok, Xie, Zhouqing, Zhu, Yu, Su, Wenjing, Zhang, Chengxin, Liu, Haoran, Xing, Chengzhi, and Liu, Jianguo
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- 2019
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22. Model Predictive Control for Smart Buildings to Provide the Demand Side Flexibility in the Multi-Carrier Energy Context: Current Status, Pros and Cons, Feasibility and Barriers
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Zong, Yi, Su, Wenjing, Wang, Jiawei, Rodek, Jakub Krzysztof, Jiang, Chuhao, Christensen, Morten Herget, You, Shi, Zhou, You, and Mu, Shujun
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- 2019
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23. RAF inhibitor PLX8394 selectively disrupts BRAF dimers and RAS-independent BRAF-mutant-driven signaling
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Yao, Zhan, Gao, Yijun, Su, Wenjing, Yaeger, Rona, Tao, Jessica, Na, Na, Zhang, Ying, Zhang, Chao, Rymar, Andrey, Tao, Anthony, Timaul, Neilawattie M., Mcgriskin, Rory, Outmezguine, Nathaniel A., Zhao, HuiYong, Chang, Qing, Qeriqi, Besnik, Barbacid, Mariano, de Stanchina, Elisa, Hyman, David M, Bollag, Gideon, and Rosen, Neal
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- 2019
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24. Targeting active RAS with molecular glue
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Su, Wenjing and Hou, Xuben
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- 2024
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25. Study on pyrolysis characteristics of red pepper stalks to analyze the changes of pyrolytic behaviors from xylophyta to herbage
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Wang, Tipeng, Zhang, Runhe, Su, Wenjing, Lu, Qiang, and Dong, Changqing
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- 2016
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26. Improving the Treatment Effect of Carotenoids on Alzheimer's Disease through Various Nano-Delivery Systems.
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Su, Wenjing, Xu, Wenhao, Liu, Enshuo, Su, Weike, and Polyakov, Nikolay E.
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ALZHEIMER'S disease , *LYCOPENE , *CAROTENOIDS , *ASTAXANTHIN , *DRUG delivery systems , *TREATMENT effectiveness , *CROCIN , *BIOACTIVE compounds - Abstract
Natural bioactive compounds have recently emerged as a current strategy for Alzheimer's disease treatment. Carotenoids, including astaxanthin, lycopene, lutein, fucoxanthin, crocin and others are natural pigments and antioxidants, and can be used to treat a variety of diseases, including Alzheimer's disease. However, carotenoids, as oil-soluble substances with additional unsaturated groups, suffer from low solubility, poor stability and poor bioavailability. Therefore, the preparation of various nano-drug delivery systems from carotenoids is a current measure to achieve efficient application of carotenoids. Different carotenoid delivery systems can improve the solubility, stability, permeability and bioavailability of carotenoids to a certain extent to achieve Alzheimer's disease efficacy. This review summarizes recent data on different carotenoid nano-drug delivery systems for the treatment of Alzheimer's disease, including polymer, lipid, inorganic and hybrid nano-drug delivery systems. These drug delivery systems have been shown to have a beneficial therapeutic effect on Alzheimer's disease to a certain extent. [ABSTRACT FROM AUTHOR]
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- 2023
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27. Autler–Townes splitting in the trap-loss fluorescence spectroscopy due to single-step direct Rydberg excitation of cesium cold atomic ensemble.
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Wang, Xin, Hou, Xiaokai, Lu, Feifei, Chang, Rui, Hao, Lili, Su, Wenjing, Bai, Jiandong, He, Jun, and Wang, Junmin
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FLUORESCENCE spectroscopy ,ULTRAVIOLET lasers ,CESIUM ,QUANTUM computing ,RYDBERG states ,MAGNETOOPTICS ,ELECTRON traps - Abstract
We experimentally investigate trap-loss spectra of the cesium 6S
1/2 (F = 4) → 71P3/2 Rydberg transition by combining the cesium atomic magneto-optical trap with the narrow-linewidth, continuously tunable 318.6 nm ultraviolet laser. Specifically, the atoms in the magneto-optical trap are excited to the Rydberg state due to the ultraviolet laser single-step Rydberg excitation, which leads to the reduction of atomic fluorescence. Based on the trap-loss spectroscopy technology, the Autler–Townes (AT) splitting due to a strong cooling laser is observed, and the parameter dependence of the AT splitting interval of trap-loss spectroscopy is investigated. The effective temperature of cold atoms is measured by using simplified time-of-flight fluorescence imaging. In addition, closed-loop feedback power stabilization of 318.6 nm ultraviolet laser is carried out. This lays the foundation for further experimental research related to the Rydberg atoms using ultraviolet lasers, which is of great significance for the development of quantum computing and quantum information. [ABSTRACT FROM AUTHOR]- Published
- 2023
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28. METTL1 drives tumor progression of bladder cancer via degrading ATF3 mRNA in an m7G-modified miR-760-dependent manner.
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Xie, Haiyun, Wang, Mingchao, Yu, Haifeng, Wang, Huan, Ding, Lifeng, Wang, Ruyue, Luo, Wenqin, Lu, Zeyi, Zheng, Qiming, Ren, Liangliang, Zhou, Zhenwei, Su, Wenjing, Xia, Liqun, and Li, Gonghui
- Published
- 2022
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29. The “Hand as Foot” teaching method in the visual pathway
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Du, Guoran, Su, Wenjing, Li, Chenglong, and Li, Zhiyong
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- 2023
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30. Modeling sensitivities of BVOCs to different versions of MEGAN emission schemes in WRF-Chem (v3.6) and its impacts over eastern China.
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Zhang, Mingshuai, Zhao, Chun, Yang, Yuhan, Du, Qiuyan, Shen, Yonglin, Lin, Shengfu, Gu, Dasa, Su, Wenjing, and Liu, Cheng
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LEAF area index ,CHEMICAL processes ,WEATHER forecasting ,ATMOSPHERIC chemistry ,METEOROLOGICAL research ,FORMALDEHYDE - Abstract
Biogenic volatile organic compounds (BVOCs) simulated by current air quality and climate models still have large uncertainties, which can influence atmospheric chemistry and secondary pollutant formation. These modeling sensitivities are primarily due to two sources. One originates from different treatments in the physical and chemical processes associated with the emission rates of BVOCs. The other is errors in the specification of vegetation types and their distribution over a specific region. In this study, the version of the Weather Research and Forecasting model coupled with Chemistry (WRF-Chem) updated by the University of Science and Technology of China (USTC version of WRF-Chem) from the public WRF-Chem(v3.6) is used. The modeling results over eastern China with different versions (v1.0, v2.0, v3.0) of the Model of Emissions of Gases and Aerosols from Nature (MEGAN) in WRF-Chem are examined or documented. Sensitivity experiments with these three versions of MEGAN and two vegetation datasets are conducted to investigate the difference of three MEGAN versions in modeling BVOCs and its dependence on the vegetation distributions. The experiments are also conducted for spring (April) and summer (July) to examine the seasonality of the modeling results. The results indicate that MEGAN v3.0 simulates the largest amount of biogenic isoprene emissions over eastern China. The different performance among MEGAN versions is primarily due to their different treatments of applying emission factors and vegetation types. In particular, the results highlight the importance of considering the sub-grid vegetation fraction in estimating BVOC emissions over eastern China, which has a large area of urbanization. Among all activity factors, the temperature-dependent factor dominates the seasonal change of activity factor in all three versions of MEGAN, while the different response to the leaf area index (LAI) change determines the difference among the three versions in seasonal variation of BVOC emissions. The simulated surface ozone concentration due to BVOCs can be significantly different (ranging from 1 to more than 10 ppbv in some regions) among the experiments with three versions of MEGAN, which is mainly due to their impacts on surface VOCs and NO x concentrations. Theoretically MEGAN v3.0 that is coupled with the land surface scheme and considers the sub-grid vegetation effect should overcome previous versions of MEGAN in WRF-Chem. However, considering uncertainties of retrievals and anthropogenic emissions over eastern China, it is still difficult to apply satellite retrievals of formaldehyde and/or limited sparse in situ observations to constrain the uncertain parameters or functions in BVOC emission schemes and their impacts on photochemistry and ozone production. More accurate vegetation distribution and measurements of biogenic emission fluxes and species concentrations are still needed to better evaluate and optimize models. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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31. Tropospheric NO2, SO2, and HCHO over the East China Sea, using ship-based MAX-DOAS observations and comparison with OMI and OMPS satellite data
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Tan, Wei, Liu, Cheng, Wang, Shanshan, Xing, Chengzhi, Su, Wenjing, Zhang, Chengxin, Xia, Congzi, Liu, Haoran, Cai, Zhaonan, and Liu, Jianguo
- Abstract
In this study, ship-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements were performed in the East China Sea (ECS) area in June 2017. The tropospheric slant column densities (SCDs) of nitrogen dioxide (NO2), sulfur dioxide (SO2), and formaldehyde (HCHO) were retrieved from the measured spectra using the differential optical absorption spectroscopy (DOAS) technique. Using the simple geometric approach, the SCDs of different trace gases observed at a 15∘ elevation angle were adopted to convert into tropospheric vertical column densities (VCDs). During this campaign, the averaged VCDs of NO2, SO2, and HCHO in the marine environment over the ECS area are 6.50×1015, 4.28×1015, and 7.39×1015 molec cm−2, respectively. In addition, the ship-based MAX-DOAS trace gas VCDs were compared with satellite observations of the Ozone Monitoring Instrument (OMI) and Ozone Mapping and Profiler Suite (OMPS). The daily OMI NO2 VCDs agreed well with ship-based MAX-DOAS measurements showing the correlation coefficient R of 0.83. In addition, the good agreements of SO2 and HCHO VCDs between the OMPS satellite and ship-based MAX-DOAS observations were also found, with correlation coefficients R of 0.76 and 0.69. The vertical profiles of these trace gases are achieved from the measured differential slant column densities (DSCDs) at different elevation angles using the optimal estimation method. The retrieved profiles displayed the typical vertical distribution characteristics, which exhibit low concentrations of , , and ppbv for NO2, SO2, and HCHO in a clean area of the marine boundary layer far from coast of the Yangtze River Delta (YRD) continental region. Interestingly, elevated SO2 concentrations can be observed intermittently along the ship routes, which is mainly attributed to the vicinal ship emissions in the view of the MAX-DOAS measurements. Combined with the on-board ozone lidar measurements, the ozone (O3) formation was discussed with the vertical profile of the HCHO∕NO2 ratio, which is sensitive to increases in NO2 concentration. This study provided further understanding of the main air pollutants in the marine boundary layer of the ECS area and also benefited the formulation of policies regulating the shipping emissions in such costal areas like the YRD region.
- Published
- 2019
32. Aneurysm Wall Enhancement in Unruptured Intracranial Aneurysms: A Histopathological Evaluation.
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Weiying Zhong, Wenjing Su, Tao Li, Xianjun Tan, Chao Chen, Qian Wang, Donghai Wang, Wandong Su, Yunyan Wang, Zhong, Weiying, Su, Wenjing, Li, Tao, Tan, Xianjun, Chen, Chao, Wang, Qian, Wang, Donghai, Su, Wandong, and Wang, Yunyan
- Published
- 2021
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33. An improved TROPOMI tropospheric HCHO retrieval over China.
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Su, Wenjing, Liu, Cheng, Chan, Ka Lok, Hu, Qihou, Liu, Haoran, Ji, Xiangguang, Zhu, Yizhi, Liu, Ting, Zhang, Chengxin, Chen, Yujia, and Liu, Jianguo
- Subjects
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TROPOSPHERIC aerosols , *RESOLUTION (Chemistry) , *OPTICAL spectroscopy , *CHEMICAL models , *RANDOM noise theory , *LIGHT absorption , *WATER vapor - Abstract
We present an improved TROPOspheric Monitoring Instrument (TROPOMI) retrieval of formaldehyde (HCHO) over China. The new retrieval optimizes the slant column density (SCD) retrieval and air mass factor (AMF) calculation for TROPOMI observations of HCHO over China. Retrieval of HCHO differential SCDs (DSCDs) is improved using the basic optical differential spectroscopy (BOAS) technique resulting in lower noise and smaller random error, while AMFs are improved with a priori HCHO profiles from a higher resolution regional chemistry transport model. Compared to the operational product, the new TROPOMI HCHO retrieval shows better agreement with ground-based Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements in Beijing. The improvements are mainly related to the AMF calculation with more precise a priori profiles in winter. Using more precise a priori profiles in general reduces HCHO vertical column densities (VCDs) by 52.37 % (± 27.09 %) in winter. Considering the aerosol effect in AMF calculation reduces the operational product by 11.46 % (± 1.48 %) and our retrieval by 17.61 % (± 1.92 %) in winter. The improved and operational HCHO are also used to investigate the spatial–temporal characteristics of HCHO over China. The result shows that both improved and operational HCHO VCDs reach maximum in summer and minimum in winter. High HCHO VCDs mainly located over populated areas, i.e., Sichuan Basin and central and eastern China, indicate a significant contribution of anthropogenic emissions. The hotspots are more obvious on the map of the improved HCHO retrieval than the operational product. The result indicates that the improved TROPOMI HCHO retrieval is more suitable for the analysis of regional- and city-scale pollution in China. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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34. Additively Manufactured mm-Wave Multichip Modules With Fully Printed “Smart” Encapsulation Structures.
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He, Xuanke, Tehrani, Bijan K., Bahr, Ryan, Su, Wenjing, and Tentzeris, Manos M.
- Subjects
LOW noise amplifiers ,SEMIRINGS (Mathematics) ,MONOLITHIC microwave integrated circuits ,THREE-dimensional printing ,FUTURES market ,ELECTROMAGNETIC interference - Abstract
This article presents the first time that an millimeter-wave (mm-wave) multichip module (MCM) with on-demand “smart” encapsulation has been fabricated utilizing additive manufacturing technologies. RF and dc interconnects were fabricated using inkjet printing, while the encapsulation was realized using 3-D printing. Inkjet-printed interconnects feature superior RF performance, better mechanical reliability, and on-demand, low-cost fabrication process. Numerous test vehicles were initially produced to evaluate these additive manufacturing technologies and compare them with traditional ribbon bonding, exhibiting a superior $|\text{S}21|$ performance throughout the whole operation range up to 40 GHz with a peak of 3.3 dB better gain for a Ka-band low noise amplifier (LNA). A fully functioning front-end MCM was fabricated using the same inkjet-printed interconnect technology, which features smart encapsulation technology fabricated using the 3-D printing and integrated on-demand “smart” encapsulation for electromagnetic interference (EMI) mitigation. The proof-of-concept MCM demonstrates exceptional performance taking advantage of a low-cost, on-demand additive manufacturing method that requires minimal tooling and process steps, which can drastically accelerate the time to market for future 5G and Internet-of-Things applications. The methodologies presented in this article could potentially enable rapid production of high-performance, high-frequency customizable circuit packaging structures with on-demand “smart” features, such as self-diagnostics, EMI/EMC filtering, and integrated sensors. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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35. Primary and secondary sources of ambient formaldehyde in the Yangtze River Delta based on Ozone Mapping and Profiler Suite (OMPS) observations.
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Su, Wenjing, Liu, Cheng, Hu, Qihou, Zhao, Shaohua, Sun, Youwen, Wang, Wei, Zhu, Yizhi, Liu, Jianguo, and Kim, Jhoon
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FORMALDEHYDE ,DELTAS ,OZONE ,ATMOSPHERIC chemistry ,INFRARED spectroscopy ,INDUSTRIAL sites - Abstract
Formaldehyde (HCHO) in the ambient air not only causes cancer but is also an ideal indicator of volatile organic compounds (VOCs), which are major precursors of ozone (O3) and secondary organic aerosol (SOA) near the surface. It is meaningful to differentiate between the direct emission and the secondary formation of HCHO for HCHO pollution control and sensitivity studies of O3 production. However, understanding of the sources of HCHO is still poor in China, due to the scarcity of field measurements (both spatially and temporally). In this study, tropospheric HCHO vertical column densities (VCDs) in the Yangtze River Delta (YRD), East China, where HCHO pollution is serious, were retrieved from the Ozone Mapping and Profiler Suite (OMPS) onboard the Suomi National Polar-orbiting Partnership (Suomi-NPP) satellite from 2014 to 2017; these retrievals showed good agreement with the tropospheric HCHO columns measured using ground-based high-resolution Fourier transform infrared spectrometry (FTS) with a correlation coefficient (R) of 0.78. Based on these results, the cancer risk was estimated both nationwide and in the YRD region. It was calculated that at least 7840 people in the YRD region would develop cancer in their lives due to outdoor HCHO exposure, which comprised 23.4 % of total national cancer risk. Furthermore, the contributions of primary and secondary sources were apportioned, in addition to primary and secondary tracers from surface observations. Overall, the HCHO from secondary formation contributed most to ambient HCHO and can be regarded as the indicator of VOC reactivity in Hangzhou and in urban areas of Nanjing and Shanghai from 2015 to 2017, due to the strong correlation between total HCHO and secondary HCHO. At industrial sites in Nanjing, primary emissions more strongly influenced ambient HCHO concentrations in 2015 and showed an obvious decreasing trend. Seasonally, HCHO from secondary formation reached a maximum in summer and a minimum in winter. In the spring, summer, and autumn, secondary formation had a significant effect on the variation of ambient HCHO in urban regions of Nanjing, Hangzhou, and Shanghai, whereas in the winter the contribution from secondary formation became less significant. A more thorough understanding of the variation of the primary and secondary contributions of ambient HCHO is needed to develop a better knowledge regarding the role of HCHO in atmospheric chemistry and to formulate effective control measures to decrease HCHO pollution and the associated cancer risk. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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36. Tropospheric NO2, SO2, and HCHO over the East China Sea, using ship-based MAX-DOAS observations and comparison with OMI and OMPS satellite data.
- Author
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Tan, Wei, Liu, Cheng, Wang, Shanshan, Xing, Chengzhi, Su, Wenjing, Zhang, Chengxin, Xia, Congzi, Liu, Haoran, Cai, Zhaonan, and Liu, Jianguo
- Subjects
LIGHT absorption ,FORMALDEHYDE ,SULFUR dioxide ,TROPOSPHERE ,NITROGEN dioxide - Abstract
In this study, ship-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements were performed in the East China Sea (ECS) area in June 2017. The tropospheric slant column densities (SCDs) of nitrogen dioxide (NO
2 ), sulfur dioxide (SO2 ), and formaldehyde (HCHO) were retrieved from the measured spectra using the differential optical absorption spectroscopy (DOAS) technique. Using the simple geometric approach, the SCDs of different trace gases observed at a 15° elevation angle were adopted to convert into tropospheric vertical column densities (VCDs). During this campaign, the averaged VCDs of NO2 , SO2 , and HCHO in the marine environment over the ECS area are 6.50 x 1015 , 4.28 x 1015 , and 7.39 x 1015 molec cm-2 [ABSTRACT FROM AUTHOR]- Published
- 2018
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37. Ozone seasonal evolution and photochemical production regime in the polluted troposphere in eastern China derived from high-resolution Fourier transform spectrometry (FTS) observations.
- Author
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Sun, Youwen, Liu, Cheng, Palm, Mathias, Vigouroux, Corinne, Notholt, Justus, Hu, Qihou, Jones, Nicholas, Wang, Wei, Su, Wenjing, Zhang, Wenqiang, Shan, Changong, Tian, Yuan, Xu, Xingwei, De Mazière, Martine, Zhou, Minqiang, and Liu, Jianguo
- Subjects
PHOTOCHEMISTRY ,TROPOSPHERIC ozone ,TROPOSPHERE ,FOURIER transform spectroscopy ,OZONE ,CARBON monoxide ,VOLATILE organic compounds - Abstract
The seasonal evolution of O
3 and its photochemical production regime in a polluted region of eastern China between 2014 and 2017 has been investigated using observations. We used tropospheric ozone (O3 ), carbon monoxide (CO), and formaldehyde (HCHO, a marker of VOCs (volatile organic compounds)) partial columns derived from high-resolution Fourier transform spectrometry (FTS); tropospheric nitrogen dioxide (NO2 , a marker of NOx (nitrogen oxides)) partial column deduced from the Ozone Monitoring Instrument (OMI); surface meteorological data; and a back trajectory cluster analysis technique. A broad O3 maximum during both spring and summer (MAM/JJA) is observed; the day-to-day variations in MAM/JJA are generally larger than those in autumn and winter (SON/DJF). Tropospheric O3 columns in June are 1.55 x 1018 molecules cm-2 (56DU (Dobson units)), and in December they are 1.05 x 1018 molecules cm-2 (39 DU). Tropospheric O3 columns in June were *** 50% higher than those in December. Compared with the SON/DJF season, the observed tropospheric O3 levels in MAM/JJA are more influenced by the transport of air masses from densely populated and industrialized areas, and the high O3 level and variability in MAM/JJA is determined by the photochemical O3 production. The tropospheric-column HCHO/NO2 ratio is used as a proxy to investigate the photochemical O3 production rate (PO3 ). The results show that the PO3 is mainly nitrogen oxide (NOx ) limited in MAM/JJA, while it is mainly VOC or mixed VOC--NOx limited in SON/DJF. Statistics show that NOx -limited, mixed VOC--NOx -limited, and VOC-limited PO3 accounts for 60.1 %, 28.7 %, and 11% of days, respectively. Considering most of PO3 is NOx limited or mixed VOC--NOx limited, reductions in NOx would reduce O3 pollution in eastern China. [ABSTRACT FROM AUTHOR]- Published
- 2018
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38. Preflight Evaluation of the Performance of the Chinese Environmental Trace Gas Monitoring Instrument (EMI) by Spectral Analyses of Nitrogen Dioxide.
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Zhang, Chengxin, Liu, Cheng, Wang, Yang, Si, Fuqi, Zhou, Haijin, Zhao, Minjie, Su, Wenjing, Zhang, Wenqiang, Chan, Ka Lok, Liu, Xiong, Xie, Pinhua, Liu, Jianguo, and Wagner, Thomas
- Subjects
NITROGEN dioxide ,REMOTE sensing ,ELECTRONIC data processing ,GAS absorption & adsorption ,LIGHT absorption - Abstract
The Environmental trace gas Monitoring Instrument (EMI) onboard the Chinese high-resolution remote sensing satellite GaoFen-5 is an ultraviolet–visible imaging spectrometer, aiming to quantify the global distribution of tropospheric and stratospheric trace gases and planned to be launched in spring 2018. The preflight calibration phase is essential to characterize the properties and performance of the EMI in order to provide information for data processing and trace gas retrievals. In this paper, we present the first EMI measurement of nitrogen dioxide (NO2) from a gas absorption cell using scattered sunlight as the light source by the differential optical absorption spectroscopy technique. The retrieved NO2 column densities in the UV and Vis wavelength ranges are consistent with the column density in the gas cell calculated from the NO2 mixing ratio and the length of the gas cell. Furthermore, the differences of the retrieved NO2 column densities among the adjoining spatial rows of the detector are less than 3%. This variation is similar to the well-known “stripes-pattern” of the Ozone Monitoring Instrument and is probably caused by remaining systematic effects like a nonperfect description of the individual instrument functions. Finally, the signal-to-noise ratios of EMI in-orbit measurements of NO2 are estimated on the basis of on-ground scattered sunlight measurements and radiative transfer model simulations. Based on our results, we conclude that the EMI is capable of measuring the global distribution of the NO2 column with the retrieval precision and accuracy better than 3% for the tested wavelength ranges and viewing angles. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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39. Smart Test Strips: Next-Generation Inkjet-Printed Wireless Comprehensive Liquid Sensing Platforms.
- Author
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Su, Wenjing and Tentzeris, Manos M.
- Subjects
- *
MICROFLUIDICS , *FLUIDICS , *NANOFLUIDS , *RADIO frequency identification systems , *IDENTIFICATION equipment - Abstract
By combining radio-frequency identification (RFID) and paper-microfluidics technologies, a low-cost first-of-its-kind platform for comprehensive liquid sensing, i.e., the “smart test strip,” is presented, which enables portable wireless real-time liquid sensing with handhold devices (e.g., cell phones), and integration of various multifunctional electrical and chemical sensors, for numerous Lab-on-Chip applications, including manufacturing control, environmental monitoring, and point-of-care medical diagnostics. The fabrication of RFID tags and two types of microfluidics are accomplished by a single inkjet-printing process in a cost-effective environmental-friendly additive manufacturing approach, which makes possible the production of disposable, lightweight, and flexible sensing platforms. Taking advantage of the proposed smart test strips platforms, we demonstrate two proof-of-concept high-performance electrical sensors based on interdigitated electrode topologies: a resistivity-based sensor with a 1782 $\Omega$/( $\Omega$*m) sensitivity; nevertheless, the proposed permittivity-based sensor with a 15%/$\epsilon _r$ sensitivity, but the proposed integrated wireless platform, can facilitate the integration of even more chemical and electrical sensors. In addition, two on-strip antenna prototypes have been designed, optimized, and tested to work at 2.4 GHz and 13.56 MHz, respectively. Furthermore, the wireless interrogation of a complete proof-of-concept smart test strip is presented, which shows an excellent sensing resolution of 1.33 $\Omega$ over the range of 0–1371 $\Omega$. [ABSTRACT FROM PUBLISHER]
- Published
- 2017
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40. High drug payload curcumin nanosuspensions stabilized by mPEG-DSPE and SPC: in vitro and in vivo evaluation.
- Author
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Hong, Jingyi, Liu, Yingying, Xiao, Yao, Yang, Xiaofeng, Su, Wenjing, Zhang, Mingzhu, Liao, Yonghong, Kuang, Haixue, and Wang, Xiangtao
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CURCUMIN ,DRUG efficacy ,BIOAVAILABILITY ,IN vitro studies ,PHARMACOKINETICS - Abstract
Context: Curcumin (CUR) is a promising drug candidate based on its broad bioactivities and good antitumor effect, but the application of CUR is potentially restricted because of its poor solubility and bioavailability. Objective: This study aims at developing a simple and effective drug delivery system for CUR to enhance its solubility and bioavailability thus to improve its antitumor efficacy. Materials and methods:Curcumin nanosuspensions (CUR-NSps) were prepared by precipitation-ultrasonication method using mPEG2000-DSPE and soybean lecithin as a combined stabilizer. Results: CUR-NSps with a high drug payload of 67.07% were successfully prepared. The resultant CUR-NSps had a mean particle size of 186.33 ± 2.73 nm with a zeta potential of −19.00 ± 1.31 mV.In vitrocytotoxicity assay showed that CUR-NSps exhibited enhanced cytotoxicity compared to CUR solution. The pharmacokinetics results demonstrated that CUR-NSps exhibited a significantly greater AUC0–24and prolonged MRT compared to CUR injections after intravenous administration. In the biodistribution study, CUR-NSps demonstrated enhanced biodistribution compared with CUR injections in liver, spleen, kidney, brain, and tumor. The CUR-NSps also showed improved antitumor therapeutic efficacy over the injections (70.34% versus 40.03%,p < 0.01). Conclusions: These results suggest that CUR-NSps might represent a promising drug formulation for intravenous administration of CUR for the treatment of cancer. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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41. Inferring global surface HCHO concentrations from multisource hyperspectral satellites and their application to HCHO-related global cancer burden estimation.
- Author
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Su, Wenjing, Hu, Qihou, Chen, Yujia, Lin, Jinan, Zhang, Chengxin, and Liu, Cheng
- Subjects
- *
HEALTH risk assessment , *HUMAN life cycle , *AIR quality management , *AIR pollutants , *TRACE gases , *TROPOSPHERIC aerosols ,POPULATION of China - Abstract
Formaldehyde (HCHO) is a toxic and hazardous air pollutant that widely exists in atmosphere. Insufficient spatial and temporal coverage of surface HCHO measurements is limiting studies on surface HCHO-related air quality management and health risk assessment. This study develops a method to derive global ground-level HCHO concentrations from satellite-based tropospheric HCHO columns using TM5-simulated surface-to-column conversion factor with coarse spatial resolution. The method improves the factor more representative in finer grids by constraining TM5-simulated vertical profile shapes with satellite HCHO columns. The surface HCHO concentrations derived by the Ozone Mapping and Profiler Suite (OMPS) show good correlation with in situ HCHO measurements (R = 0.59) from the U.S. Environmental Protection Agency surface network. We investigated how surface HCHO relates to urbanization and population aggregation over seven regions with high HCHO pollution. The results show urban HCHO increases as a power function with population size in China, India, and West Asia. HCHO concentrations in rural aeras also present strong log–log relationship with population aggregation in China, India, the United States, and Europe. Moreover, OMPS-derived ground-level HCHO concentrations were used to estimate global cancer burden caused by long-term outdoor HCHO exposure. The results show that up to 418188 more people worldwide will develop this cancer during the human life cycle. The global cancer burden is mainly from the South-East Asia region (33.11 %) and the Western Pacific region (22.95 %). This cancer occurrence in India and China is ranked 1st and 2nd in the world due to the large population size and serious HCHO pollution. Besides, global surface HCHO concentrations and cancer burden derived from the Environmental Trace Gases Monitoring Instrument which is China's first hyperspectral space-based spectrometer are found similar patterns with that from OMPS. Our results provide new insight into the impact of population urbanization on HCHO pollution and global outdoor HCHO-caused health risks. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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42. Additively Manufactured Microfluidics-Based “Peel-and-Replace” RF Sensors for Wearable Applications.
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Su, Wenjing, Cook, Benjamin S., and Tentzeris, Manos M.
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- *
MICROFLUIDICS , *RADIO frequency identification systems , *WEARABLE technology , *INK-jet printers , *LITHOGRAPHY - Abstract
This paper demonstrates the first-of-its-kind additively manufactured microfluidics-based flexible RF sensor, combining microfluidics, inkjet-printing technology, and soft lithography, which could potentially enable the first “real-world” wearable “smart skin” applications. A low-cost, rapid, low-temperature, and zero-waste fabrication process is introduced, which can be used to realize complex microfluidic channel networks with virtually any type of sensing element embedded. For proof-of-concept purposes, a reusable and flexible microfluidics sensor was prototyped using this process, which only requires 0.6- \mu \text L fluid volume to produce a 44% frequency shift between an empty ( \epsilon r=1 ) and a water-filled channel ( \epsilon r=73 ), demonstrating a sensitivity that is higher than most previously reported microfluidics-based microwave sensors. Seven different fluids were used to measure the sensitivity of the prototype and an overall sensitivity of 24\%/ \log (\epsilon r) was observed. The “peel-and-replace” capability of the presented sensor not only facilitates the cleaning process for sensor reusability, but it also enables sensitivity tunability. For bent/conformed configurations, the sensor’s functionality is good even for a bending radius down to 7 mm, demonstrating its great flexibility. After bending multiple times, the sensor still exhibits a very good performance repeatability, which verifies its reusability feature. The introduced additively manufactured RF microfluidics-based sensor would be well suited for numerous wearable and conformal fluid sensing applications (e.g., bodily fluids analyzing and food monitoring), while it could also be utilized in a variety of microfluidics-reconfigurable microwave components. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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43. ARAF protein kinase activates RAS by antagonizing its binding to RASGAP NF1.
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Su, Wenjing, Mukherjee, Radha, Yaeger, Rona, Son, Jieun, Xu, Jianing, Na, Na, Merna Timaul, Neilawattie, Hechtman, Jaclyn, Paroder, Viktoriya, Lin, Mika, Mattar, Marissa, Qiu, Juan, Chang, Qing, Zhao, Huiyong, Zhang, Jonathan, Little, Megan, Adachi, Yuta, Han, Sae-Won, Taylor, Barry S., and Ebi, Hiromichi
- Subjects
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PROTEIN kinases , *GTPASE-activating protein , *GUANOSINE triphosphatase , *PROTEIN-tyrosine phosphatase , *PHOSPHOPROTEIN phosphatases , *GUANOSINE triphosphate , *EPIDERMAL growth factor receptors - Abstract
RAF protein kinases are effectors of the GTP-bound form of small guanosine triphosphatase RAS and function by phosphorylating MEK. We showed here that the expression of ARAF activated RAS in a kinase-independent manner. Binding of ARAF to RAS displaced the GTPase-activating protein NF1 and antagonized NF1-mediated inhibition of RAS. This reduced ERK-dependent inhibition of RAS and increased RAS-GTP. By this mechanism, ARAF regulated the duration and consequences of RTK-induced RAS activation and supported the RAS output of RTK-dependent tumor cells. In human lung cancers with EGFR mutation, amplification of ARAF was associated with acquired resistance to EGFR inhibitors, which was overcome by combining EGFR inhibitors with an inhibitor of the protein tyrosine phosphatase SHP2 to enhance inhibition of nucleotide exchange and RAS activation. [Display omitted] • ARAF activates RAS by antagonizing its interaction with NF1 • ARAF controls the duration and consequences of receptor-activated ERK signaling • Increased ARAF expression in lung cancer causes acquired resistance to EGFR inhibitors Su et al. reveal that ARAF activates RAS by antagonizing its binding to the NF1 RASGAP. By this mechanism, the abundance of ARAF determines RAS-GTP levels and the duration and biologic consequences of RTK activation of RAS signaling. Moreover, ARAF amplification causes resistance of lung cancers to EGFR inhibition. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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44. First global observation of tropospheric formaldehyde from Chinese GaoFen-5 satellite: Locating source of volatile organic compounds.
- Author
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Su, Wenjing, Liu, Cheng, Hu, Qihou, Zhang, Chengxin, Liu, Haoran, Xia, Congzi, Zhao, Fei, Liu, Ting, Lin, Jinan, and Chen, Yujia
- Subjects
VOLATILE organic compounds ,FORMALDEHYDE ,TRACE gases ,LIGHT absorption ,ATMOSPHERIC chemistry ,OPTICAL spectroscopy ,SIGNAL-to-noise ratio - Abstract
Satellite remote sensing is an important technique providing long-term and large-scale information of formaldehyde (HCHO), which plays a crucial role in atmospheric chemistry. Low signal-to-noise ratio and poor stability of the Environmental Trace Gases Monitoring Instrument (EMI) On board Gaofen-5 satellite, the first Chinese space-borne spectrometer, make HCHO retrieval extremely difficult. Here we firstly retrieved HCHO vertical column densities (VCDs) from EMI through in-flight spectral calibration, retrieval setting optimization and stripe correction. Retrieved EMI HCHO VCDs correlate well with those measured by Multi-AXis Differential Optical Absorption Spectroscopy (MAX-DOAS) with normalize mean bias (NMB) below 25%. EMI HCHO VCDs are comparable with those observed by Ozone Monitoring Instrument (OMI) and TROPOspheric Monitoring Instrument (TROPOMI). This study reveals that HCHO can be observed successfully by algorithm optimization despite of poor performance of space-borne spectrometer. The retrieved EMI HCHO VCDs are applied to locate emission sources of volatile organic compounds (VOCs). • First retrieval of HCHO from Environmental Trace Gases Monitoring Instrument (EMI). • Algorithm optimization is proposed suitable for EMI HCHO retrieval. • HCHO vertical column density (VCD) correlates well with ground-based measurements. • EMI HCHO measurements are improved to a comparable level with OMI measurements. • HCHO hotspots and source of volatile organic compounds are captured successfully by EMI. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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45. Opposite impact of emission reduction during the COVID-19 lockdown period on the surface concentrations of PM2.5 and O3 in Wuhan, China.
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Yin, Hao, Liu, Cheng, Hu, Qihou, Liu, Ting, Wang, Shuntian, Gao, Meng, Xu, Shiqi, Zhang, Chengxin, and Su, Wenjing
- Subjects
COVID-19 ,STAY-at-home orders ,COVID-19 pandemic ,AIR pollutants ,ENVIRONMENTAL monitoring ,VOLATILE organic compounds - Abstract
To prevent the spread of the COVID-19 epidemic, the Chinese megacity Wuhan has taken emergent lockdown measures starting on January 23, 2020. This provided a natural experiment to investigate the response of air quality to such emission reductions. Here, we decoupled the influence of meteorological and non-meteorological factors on main air pollutants using generalized additive models (GAMs), driven by data from the China National Environmental Monitoring Center (CNEMC) network. During the lockdown period (Jan. 23 – Apr. 8, 2020), PM 2.5 , PM 10 , NO 2 , SO 2 , and CO concentrations decreased significantly by 45 %, 49 %, 56 %, 39 %, and 18 % compared with the corresponding period in 2015–2019, with contributions by S(meteos) of 15 %, 17 %, 13 %, 10 %, and 6 %. This indicates an emission reduction of NO x at least 43 %. However, O 3 increased by 43 % with a contribution by S(meteos) of 6 %. In spite of the reduced volatile organic compound (VOC) emissions by 30 % during the strict lockdown period (Jan. 23 – Feb. 14, 2020), which likely reduced the production of O 3 , O 3 concentrations increased due to a weakening of the titration effect of NO. Our results suggest that conventional emission reduction (NO x reduction only) measures may not be sufficient to reduce (or even lead to an increase of) surface O 3 concentrations, even if reaching the limit, and VOC-specific measures should also be taken. [Display omitted] • COVID-19 lockdown caused a significant reduction in pollutant, except ozone. • GAMs model can explain nonlinear relationship between pollutants and meteorology. • Increasing of ozone mainly due to weakening of titration effect. • Ozone pollution needs to be controlled by a variety of pollutants. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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46. Observations by Ground-Based MAX-DOAS of the Vertical Characters of Winter Pollution and the Influencing Factors of HONO Generation in Shanghai, China.
- Author
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Xu, Shiqi, Wang, Shanshan, Xia, Men, Lin, Hua, Xing, Chengzhi, Ji, Xiangguang, Su, Wenjing, Tan, Wei, Liu, Cheng, and Hu, Qihou
- Subjects
AIR pollutants ,WATER vapor ,POLLUTION ,TROPOSPHERIC chemistry ,TRACE gases ,NITROUS acid ,WEATHER ,AIR pollution - Abstract
Analyzing vertical distribution characters of air pollutants is conducive to study the mechanisms under polluted atmospheric conditions. Nitrous acid (HONO) is a kind of crucial species in photochemical cycles. Exploring the influence and sources of HONO in air pollution at different altitudes offers some insights into the research of tropospheric oxidation chemistry processes. Ground-based multi-axis differential optical absorption spectroscopy (MAX-DOAS) measurements were conducted in Shanghai, China, from December 2017 to March 2018 to investigate vertical distributions and diurnal variations of trace gases (NO
2 , HONO, HCHO, SO2 , and water vapor) and aerosol extinction coefficient in the boundary layer. Aerosol and NO2 showed decreasing profile exponentially, SO2 and HCHO concentrations were observed relatively high values in the middle layer. SO2 was caused by industrial emissions, while HCHO was from secondary sources. As for HONO, below 0.82 km, the heterogeneous reactions of NO2 impacted on forming HONO, while in the upper layers, vertical diffusion might be the dominant source. The contribution of OH production from HONO photolysis at different altitudes was mainly controlled by the concentration of HONO. MAX-DOAS measurements characterize the vertical structure of air pollutants in Shanghai and provide further understanding for HONO formation, which can help deploy advanced measurement platforms of regional air pollution over eastern China. [ABSTRACT FROM AUTHOR]- Published
- 2021
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47. Recommendations for HCHO and SO 2 Retrieval Settings from MAX-DOAS Observations under Different Meteorological Conditions.
- Author
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Javed, Zeeshan, Tanvir, Aimon, Bilal, Muhammad, Su, Wenjing, Xia, Congzi, Rehman, Abdul, Zhang, Yuanyuan, Sandhu, Osama, Xing, Chengzhi, Ji, Xiangguang, Xie, Mingjie, Liu, Cheng, and Wang, Yuhang
- Subjects
TRACE gases ,ROOT-mean-squares ,OPTICAL spectroscopy ,LIGHT absorption - Abstract
Recently, the occurrence of fog and haze over China has increased. The retrieval of trace gases from the multi-axis differential optical absorption spectroscopy (MAX-DOAS) is challenging under these conditions. In this study, various reported retrieval settings for formaldehyde (HCHO) and sulfur dioxide (SO
2 ) are compared to evaluate the performance of these settings under different meteorological conditions (clear day, haze, and fog). The dataset from 1st December 2019 to 31st March 2020 over Nanjing, China, is used in this study. The results indicated that for HCHO, the optimal settings were in the 324.5–359 nm wavelength window with a polynomial order of five. At these settings, the fitting and root mean squared (RMS) errors for column density were considerably improved for haze and fog conditions, and the differential slant column densities (DSCDs) showed more accurate values compared to the DSCDs between 336.5 and 359 nm. For SO2 , the optimal settings for retrieval were found to be at 307–328 nm with a polynomial order of five. Here, root mean square (RMS) and fitting errors were significantly lower under all conditions. The observed HCHO and SO2 vertical column densities were significantly lower on fog days compared to clear days, reflecting a decreased chemical production of HCHO and aqueous phase oxidation of SO2 in fog droplets. [ABSTRACT FROM AUTHOR]- Published
- 2021
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48. Quantifying Contributions of Local Emissions and Regional Transport to NO X in Beijing Using TROPOMI Constrained WRF-Chem Simulation.
- Author
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Zhu, Yizhi, Hu, Qihou, Gao, Meng, Zhao, Chun, Zhang, Chengxin, Liu, Ting, Tian, Yuan, Yan, Liu, Su, Wenjing, Hong, Xinhua, Liu, Cheng, and Cartalis, Constantinos
- Subjects
EMISSION inventories ,ATMOSPHERIC transport ,AIR quality ,METEOROLOGICAL research ,AIR pollutants ,WEATHER forecasting ,INVENTORIES - Abstract
Air quality is strongly influenced by both local emissions and regional transport. Atmospheric chemical transport models can distinguish between emissions and regional transport sources in air pollutant concentrations. However, quantifying model inventories is challenging due to emission changes caused by the recent strict control measures taken by the Chinese government. In this study, we use NO
2 column observations from the Tropospheric Monitoring Instrument to retrieve top-down nitrogen oxide (NOX ) emissions and quantify the contributions of local emissions and regional transport to NOx in Beijing (BJ), from 1 November 2018 to 28 February 2019 (W_2018) and 1 November 2019 to 29 February 2020 (W_2019). In W_2018 and W_2019, the BJ bottom-up NOX emissions from the multi-resolution emission inventory for China in 2017 were overestimated by 11.8% and 40.5%, respectively, and the input of NOX from other cities to BJ was overestimated by 10.9% and 51.6%, respectively. The simulation using our adjusted inventory exhibited a much higher spatial agreement (slope = 1.0, R2 = 0.79) and reduced a mean relative error by 45% compared to those of bottom-up NOX emissions. The top-down inventory indicated that (1) city boundary transport contributes approximately 40% of the NOX concentration in BJ; (2) in W_2019, NOX emissions and transport in BJ decreased by 20.4% and 17.2%, respectively, compared to those of W_2018; (3) in W_2019, NOX influx substantially decreased (−699 g/s) in BJ compared to that of W_2018 despite negative meteorological conditions that should have increased NOx influx by +503 g/s. Overall, the contribution of intercity input to NOx in BJ has declined with decreasing emissions in the surrounding cities due to regional cooperative control measures, and the role of local emissions in BJ NOx levels was more prominent. Our findings indicate that local emissions may play vital roles in regional center city air quality. [ABSTRACT FROM AUTHOR]- Published
- 2021
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49. Distinct Regimes of O 3 Response to COVID-19 Lockdown in China.
- Author
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Liu, Shanshan, Liu, Cheng, Hu, Qihou, Su, Wenjing, Yang, Xian, Lin, Jinan, Zhang, Chengxin, Xing, Chengzhi, Ji, Xiangguang, Tan, Wei, Liu, Haoran, Gao, Meng, Lu, Xiao, and Griffiths, Paul
- Subjects
COVID-19 ,EMISSIONS (Air pollution) ,STAY-at-home orders ,AIR pollutants ,NITROGEN dioxide - Abstract
Restrictions on human activities remarkably reduced emissions of air pollutants in China during the COVID-19 lockdown periods. However, distinct responses of O
3 concentrations were observed across China. In the Beijing–Tianjin–Hebei (BTH) and Yangtze River Delta (YRD) regions, O3 concentrations were enhanced by 90.21 and 71.79% from pre-lockdown to lockdown periods in 2020, significantly greater than the equivalent concentrations for the same periods over 2015–2019 (69.99 and 43.62%, p < 0.001). In contrast, a decline was detected (−1.1%) in the Pearl River Delta (PRD) region. To better understand the underlying causes for these inconsistent responses across China, we adopted the least absolute shrinkage and selection operator (Lasso) and ordinary linear squares (OLS) methods in this study. Statistical analysis indicated that a sharp decline in nitrogen dioxide (NO2 ) was the major driver of enhanced O3 in the BTH region as it is a NOx -saturated region. In the YRD region, season-shift induced changes in the temperature/shortwave radiative flux, while lockdown induced declines in NO2 , attributable to the rise in O3 . In the PRD region, the slight drop in O3 is attributed to the decreased intensity of radiation. The distinct regimes of the O3 response to the COVID-19 lockdown in China offer important insights into different O3 control strategies across China. [ABSTRACT FROM AUTHOR]- Published
- 2021
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50. Development and Application of HECORA Cloud Retrieval Algorithm Based On the O2-O2 477 nm Absorption Band.
- Author
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Wang, Shuntian, Liu, Cheng, Zhang, Wenqiang, Hao, Nan, Gimeno García, Sebastián, Xing, Chengzhi, Zhang, Chengxin, Su, Wenjing, and Liu, Jianguo
- Subjects
ALGORITHMS ,ALBEDO ,CLOUD computing ,TRACE gases ,LIGHT absorption ,OPTICAL spectroscopy ,RADIATIVE transfer - Abstract
In this paper, we present the Hefei EMI Cloud Retrieval Algorithm (HECORA), which uses information from the O
2 -O2 absorption band around 477 nm to retrieve effective cloud fraction and effective cloud pressure from satellite observations. The retrieved cloud information intends to improve the atmospheric trace gas products based on the Environment Monitoring Instrument (EMI) spectrometer. The HECORA method builds on OMCLDO2 and presents some evolutions. The Vector Linearized Discrete Ordinate Radiative Transfer (VLIDORT) model has been used to produce the Top of the Atmosphere (TOA) reflectance Look-up Tables (LUT) as a function of the cloud fraction and cloud pressure. Applying the Differential Optical Absorption Spectroscopy (DOAS) technique to the synthetic reflectance LUT, the reflectance spectra can be associated with O2 -O2 geometrical vertical column densities (VCDgeo ) and continuum reflectance. This is the core of the retrieval method, since there is a one-to-one relationship between O2 -O2 VCDgeo and continuum reflectance, on the one hand, and effective cloud fraction and effective cloud pressure, on the other hand, for a given illumination and observing geometry and given surface height and surface albedo. We first used the VLIDORT synthetic spectra to verify the HECORA algorithm and obtained good results in both the Lambertian cloud model and the scattering cloud model. Secondly, HECORA is applied to OMI and TROPOMI and compared with OMCLDO2, FRESCO+, and OCRA/ROCINN cloud products. Later, the cloud pressure results from TROPOMI observations obtained using HECORA and FRESCO+ are compared with the CALIOP Cloud Layer product. HECORA is closer to the CALIOP results under low cloud conditions, while FRESCO+ is closer to high clouds due to the higher sensitivity of the O2 A-band to cloud vertical information. Finally, HECORA is applied to the TROPOMI NO2 retrieval. Validation of the tropospheric NO2 VCD with ground-based MAX-DOAS measurements shows that choosing HECORA cloud products to correct for photon path variations on the TROPOMI tropospheric NO2 VCD retrievals has better performance than using FRESCO+ under low cloud conditions. In conclusion, this paper shows that the HECORA cloud products are in good agreement with the well-established cloud products and that they are suitable for correcting the effect of cloud in trace gas retrievals. Therefore, HECORA has the potential to be applied to EMI. [ABSTRACT FROM AUTHOR]- Published
- 2020
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