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1.
Huan Jing Ke Xue ; 45(5): 2516-2524, 2024 May 08.
Artículo en Chino | MEDLINE | ID: mdl-38629517

RESUMEN

This study selected 15 key predictors of the maximum of 8-hour averaged ozone (O3) concentration (O3-8h), using the O3 concentration of Haikou and ERA5 reanalysis data from 2015 to 2020, and constructed a multiple linear regression (MLR) model, support vector machine (SVM) model, and BP neural network (BPNN) model, to predict and test the O3-8h concentration of Haikou in 2021. The results showed that the absolute value of correlation coefficients between the O3-8h and related key prediction factors was mainly among 0.2 and 0.507. The 1 000 hPa relative humidity (RH1000), wind direction (WD1000), and 875 hPa meridional wind (v875) showed a good indicative effect on the O3-8h, with the absolute correlation value exceeding 0.4. The three prediction models could predict the seasonal variation in the O3-8h in Haikou, which was larger in the winter half year and smaller in the summer half year. The root mean square error(RMSE) was the smallest (22.29 µg·m-3) in the BPNN model. The correlation coefficients between the predicted values of three statistical models and observations were ranked as 0.733 (BPNN) > 0.724 (SVM) > 0.591 (MLR), all passing the 99.9% significance test. For the prediction of the O3-8h level, we found that TS scores of these three prediction models decreased with the increase in O3-8h concentration level. Relatively, the point over rate and not hit rate increased with the rise in O3-8h concentration level. TS scores of the SVM and BPNN model were relatively larger than those of MLR, especially in the light pollution level with TS scores remaining above 70%, indicating a better prediction capability.

2.
Eur J Pharmacol ; 966: 176345, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38244760

RESUMEN

The post-translational modification of cysteine through redox reactions, especially S-sulfhydration, plays a critical role in regulating protein activity, interactions, and spatial arrangement. This review focuses on the impact of protein S-sulfhydration on vascular function and its implications in vascular diseases. Dysregulated S-sulfhydration has been linked to the development of vascular pathologies, including aortic aneurysms and dissections, atherosclerosis, and thrombotic diseases. The H2S signaling pathway and the enzyme cystathionine γ-lyase (CSE), which is responsible for H2S generation, are identified as key regulators of vascular function. Additionally, potential therapeutic targets for the treatment of vascular diseases, such as the H2S donor GYY4137 and the HDAC inhibitor entinostat, are discussed. The review also emphasizes the antithrombotic effects of H2S in regulating platelet aggregation and thrombosis. The aim of this review is to enhance our understanding of the function and mechanism of protein S-sulfhydration modification in vascular diseases, and to provide new insights into the clinical application of this modification.


Asunto(s)
Aterosclerosis , Sulfuro de Hidrógeno , Humanos , Sulfuro de Hidrógeno/metabolismo , Aterosclerosis/tratamiento farmacológico , Procesamiento Proteico-Postraduccional , Cistationina gamma-Liasa/metabolismo
3.
Huan Jing Ke Xue ; 37(9): 3237-3248, 2016 Sep 08.
Artículo en Chino | MEDLINE | ID: mdl-29964756

RESUMEN

Based on haze observation and related meteorological data from the surface weather stations in China during 1960-2013, we analyzed the variation of haze days and its relationship to meteorological elements using climatic linear-trend estimation, cluster analysis, cumulative departure and the Mann-Kendall test. The results showed that the haze events occurred mainly in mid-eastern and southern China, especially in Beijing, central and southern areas of Shanxi, Henan, the Yangtze River Delta and Pearl River Delta areas. At the same time, the haze days were less frequently observed in western and northeastern China. The occurrence of haze days was increasing in the past 54 years, which was consistent with the total energy consumption in China. While the emission of air pollutant could be an important factor of haze increase, the adverse weather conditions also played a role. The correlation coefficients of precipitation, average wind speed, sunshine duration and relative humidity with haze days were -0.653, -0.635, -0.462 and -0.699, respectively, which all exceeded the 99.9% significance. Cluster analysis showed that haze days of stations with very significant increase, significant increase and obvious increase have accelerated in recent years, and the trend of cumulative variance type was fall-flat-rise. Haze days of slight rise station increased from 1960s to the late1970s and after 2000, of which cumulative variance type was multi wobbled. Moreover, Haze days of slight fall and obvious fall stations increased from 1960s to 1970s, and their cumulative variance types were rise-gently-fall. Furthermore, haze days showed mutation from more to less during 1992 to 1993.

4.
Huan Jing Ke Xue ; 36(1): 18-24, 2015 Jan.
Artículo en Chino | MEDLINE | ID: mdl-25898642

RESUMEN

The temporal-spatial characteristics of the tropospheric column NO2 (TroNO2) and total column NO2 (TotNO2) over Hainan Island are analyzed using remote sensing data derived from OMI sensor, and also combining surface wind, SO2, HYSPLIT model to research the source of atmospheric pollutants over Hainan Island. The results show that: The value of NO2 in northern area is higher than that in southern area, and the value of NO, in central mountainous area is lower than those other places. In addition, the seasonal variation of NO2 indicates that NO2 is higher in winter and lower in summer, which can be attributed to precipitation in summer and external transport of atmospheric pollutants in winter. Long-term changes of NO2 in Hainan Island appear opposite trends during winter and summer, which is declining in winter and has a weak increase in summer. The reasonable explanation is that local emissions of pollutants play an important role in summer, but external transport is the main resource of pollutants over Hainan Island. The TroNO2 in Haikou City has a good relationship with favorable delivered days in PRD, the correlation coefficient is 0.84 with 99% confidence level. Moreover, there are 3 transport paths in Dec. 2013 which can impact Haikou City from backward trajectory analysis, but all of them pass through the PRD, which can further prove that atmospheric pollutants of Hainan Island in winter are mainly delivery from PRD region.


Asunto(s)
Contaminantes Atmosféricos/análisis , Óxido Nítrico/análisis , China , Monitoreo del Ambiente , Islas , Modelos Teóricos , Tecnología de Sensores Remotos , Estaciones del Año , Análisis Espacio-Temporal , Viento
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