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1.
Huan Jing Ke Xue ; 45(2): 655-667, 2024 Feb 08.
Artigo em Zh | MEDLINE | ID: mdl-38471906

RESUMO

Based on the continuous data of O3, NO, NO2, and NOx and the meteorological data from March 2019 to February 2020 at six atmospheric composition observation stations in Shanxi Province, the characteristics and influence factors of O3 volume fractions were studied using statistical analysis and backward trajectory analysis. The results showed that O3 volume fractions were generally higher from April to September and lower from October to the following March. During the study period, O3 pollution represented by φ(MDA8O3), i.e., the maximum daily 8-h average of O3 volume fractions, was the most serious at the Jincheng and Linfen stations in the south of Shanxi, followed by that in the Wutaishan, Shuozhou, and Datong stations in the north, with the least pollution occurring at the Taiyuan station in the middle. There were differences between the urban and alpine stations, although their seasonal O3 volume fractions were both summer > spring > autumn > winter. O3 volume fractions at the urban station were usually lower than those at the alpine station; O3 at the urban station might have been influenced by photochemical reactions with precursor NOx; however, this was not the main source of high O3 at the alpine station. The peak and valley values appeared at 15:00 and 06:00, respectively, at the urban station, whereas they appeared at 20:00 and 10:00, respectively, at the alpine station, representing diametrically opposite diurnal variation patterns. Further, the daily amplitude of O3 at the urban station was much larger than that at the alpine station. For urban stations specifically, temperature was the most important meteorological factor affecting O3 volume fraction, compared with sunlight hours, precipitation, and total cloud cover. The NO2 volume fraction in the daytime affected the daily amplitude of O3; although the photochemical generation potential of O3 at the Taiyuan station was good, the O3 volume fractions were the lowest among urban stations due to strong NO titration. The higher O3 corresponded to lower NOx in which NO2 was dominant, and the higher NOx was largely composed of NO, under which conditions O3 would be depleted completely. The surface wind that affected O3 volume fractions of all stations primarily came from the southeast, south, and southwest, and specific wind speed led to the increase in O3 volume fraction. The geographical situation of the station would cause the difference in the transport of atmospheric pollutants, whereas the horizontal transmissions of high O3 from the North China Plain and Fenwei Plain were likely to be the common reason for the increase in O3 volume fraction in Shanxi.

2.
Huan Jing Ke Xue ; 40(11): 4801-4809, 2019 Nov 08.
Artigo em Zh | MEDLINE | ID: mdl-31854545

RESUMO

Because of the atmospheric regional transmission, the air quality in Taiyuan is susceptible to air pollution from the surrounding areas. The annual and seasons air pollution characteristics of Taiyuan from 2014 to 2018 were analyzed using the environmental air quality index (AQI), the hourly backward trajectories in autumn and winter of 2014-2017 were calculated using the HYSPLIT model. The results showed that the air pollution situation in Taiyuan is not optimistic. There was a large fluctuation in the number of good days from 2014 to 2018, especially in the compliance rate of air quality, which varied from 64% to less than 50% over the past two years. However, the proportion of good days gradually increased in autumn and winter, exceeding 50% in 2018, and the trend in air quality improvement was obvious. The results also showed that air pollution may be more serious in spring and summer. Pollution types changed; whether annual or autumn and winter the days, PM2.5 as the main pollutant decreased significantly and the days with PM10 increased significantly in autumn and winter. Based on the backward trajectory model and it combination with the AQI, using Taiyuan as the starting point, the backward 72 hour trajectory from 00:00 on September 1, 2014 to 23:00 on December 31,2017 was calculated. The trajectory clustering analysis method, the potential source contribution factor weights (PSCF), and the concentration of the trajectory analysis (CWT) were used to discuss the source of contaminants in Taiyuan. The results showed that the simulated track after a clustering analysis could be divided into 8 categories, 53% of the trajectories come from the western region, 21% from the northwest, 12% from the southwest, and 14% from the east in autumn and winter of 2014-2017. The southwest trajectory was the main trajectory for the transportation of foreign pollutants into Taiyuan, and it has a significant impact on Taiyuan's air quality. PSCF and CWT analysis showed that the major potential sources affecting Taiyuan's air quality were mainly located in Fenwei plain, i. e., Hanzhong, Xi'an in Shaanxi Province, and Lvliang and Linfen in Shanxi Province. Establishing a joint prevention and control mechanism in the Fenwei plain and its surrounding areas would be of great significance for controlling pollution in the area.

3.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 20(5): 454-6, 2003 Oct.
Artigo em Zh | MEDLINE | ID: mdl-14556208

RESUMO

OBJECTIVE: To screen the variations of TG interacting factor(TGIF) gene in encoding sequence in Chinese high myopia patients and normal controls and to analyze the SNPs of TGIF gene encoding sequence in Chinese population. METHODS: Genomic DNA was collected from 204 probands with high myopia and 112 unrelated persons without high myopia. The coding sequences of TGIF gene in 316 subjects were analyzed by using exon-by-exon PCR heteroduplex-SSCP analysis and sequencing. RESULTS: There were 3 types of SNP and one single nucleotide mutation in the coding sequence of TGIF gene: IVS-2 nt350 G --> T(36/204), codon140 CCA --> CCG; Pro140Pro codon163 CCG --> CTG;Pro163Leu and codon126 GTG --> GCG; Val126Ala(1/204). The SNPs of codon140 CCA --> CCG and codon163 CCG --> CTG were composed of 3 alleles and 5 genotypes in Chinese population which abide by Hardy-Weinberg law. CONCLUSION: There was no evidence to prove that mutations in the TGIF gene are responsible for the high myopia in Chinese. Three SNPs of coding sequence TGIF gene in Chinese population abide by Hardy-Weinberg law.


Assuntos
Proteínas de Homeodomínio/genética , Miopia/genética , Polimorfismo de Nucleotídeo Único , Proteínas Repressoras/genética , China , DNA/química , DNA/genética , Análise Mutacional de DNA , Frequência do Gene , Humanos , Mutação , Miopia/patologia , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples
4.
Yi Chuan ; 26(2): 155-9, 2004 Mar.
Artigo em Zh | MEDLINE | ID: mdl-15639979

RESUMO

To investigate the association between variations of ZFP161 gene and high myopia, A total of 204 probands with simple high myopia(< or = -6.0 dipoters) were collected while 116 normal persons from different families without high myopia or related disease were used as controls. Genomic DNA was prepared from the peripheral leucocytes. The coding sequences of ZFP161 gene in 320 subjects were analyzed by using exon-by-exon PCR-heteroduplex-SSCP analysis. Identification of the Variations by cloning and sequencing, combinated with controls and family analysis, was used to disclose the correlation between ZFP161 gene and high myopia. A mutation of ZFP161 gene was identified as an insertion of AT before the 58th nucleotide of intron 1 (IVS1 58-59)(1/204) and a variation of ZFP161 gene was identified as a heterozygous C to A of the 168th nucleotide in exon 2 (Codon56, GCC-->GCA, Ala56Ala). Ala56Ala is a non-sense mutation identified in 5 of the 204 patients and 3 of 116 controls. No evidence shows that these variations are responsible for high myopia.


Assuntos
Povo Asiático/genética , Proteínas de Ligação a DNA/genética , Éxons/genética , Mutação , Miopia/genética , Proteínas Repressoras/genética , Sequência de Bases , China , Códon sem Sentido , DNA/genética , Humanos , Íntrons/genética , Fatores de Transcrição Kruppel-Like , Mutagênese Insercional , Miopia/metabolismo , Mutação Puntual , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples
5.
Yi Chuan ; 24(5): 523-6, 2002 Sep.
Artigo em Zh | MEDLINE | ID: mdl-16135441

RESUMO

To analyze the relationship of the peripherin gene(PRPH, OMIM17071) mutations with high myopia,genomic DNA was collected from 180 probands with high myopia (TTT(Phe21Phe,4/180), nt2138C-->G(IVS3,1/180), codon277 GCC-->ACC(Ala277Thr,8/180), codon237 CCA-->TCA (Arg237stop,1/180), codon292CCG-->CCA (Ala292Ala,1/180),codon361CUG-->CUC(Leu361Leu,12/180), codon369 AAA-->AAG(Lys369Lys,12/180),nt3331G-->C(IVS7,3/180)were detected in a number of probands as indicated in the blanket. Of the 8 variations one( codon 277,G-->A,Ala277Thr) is a missense mutation identified in 8 of the 180patients and one of 60 controls; The mutation of codon361 and codon 369 were synonymous one and linkage each other; Another one(codon237,CCA-->TCA,Arg237stop) is a heterozygous nonsense mutation identified in one patient with autosomal recessive inheritance mode population but not in the 60 normal controls. The others were synonymous mutations. Eight nucleotide variations were found in the PRPH gene. We found no evidence that mutations in the PRPH gene are responsible for the high myopia in Chinese.

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