Impact of a Dust Storm on Characteristics of Particle Matter (PM) in Guangzhou, China

Qi Fan,Chong Shen,Xuemei Wang,Yuan Li,Wei Huang,Guixiong Liang,Shaoyi Wang,Zhuoer Huang 한국기상학회 2013 Asia-Pacific Journal of Atmospheric Sciences Vol.49 No.1

A strong dust-storm (23-25 April, 2009) occurred in the provinces of Inner Mongolia, Gansu, and Shanxi, North China. Cities along the storm path (from north to south: Xi’ning, Lanzhou,Chengdu, Changsha, and Guangzhou) all experienced a sharp increase in particle matter (PM10) concentration. This is the first case that an Asian dust storm hit Guangzhou in Southern China. The impacts of dust storm on the characteristics of PM were investigated using samples collected in Guangzhou during 27-29 April, 2009. In addition, the mass concentration and chemical composition during a normal non-dust period (12-14 May, 2009) were compared with those in dust period. The results show that the concentration of PM10during the dust episode (0.231 mg m−3) was twice higher than that in the non-dust episode (0.103 mg m−3). Chemical analysis showed that concentrations of metal elements, enrichment factors of metal elements, and soluble ions during the dust episode were very different from those of non-dust. The total concentration of metal elements content in PM10 was 53.5 μg m−3 in the dust episode, which is about two times higher than that in non-dust episode (28.5 μgm−3). Increases in concentrations of Na, Ti, Zn, Cu, and Cr ranged from zero to 100% during the dust episode. However, the enrichment factors in non-dust episode were higher than that in dust-storm period,indicating that the above five chemicals originated mainly from local sources in Guangzhou. The concentrations of K, Mg, Al, Fe, Mn, V,and Co increased by over 100% in the dust episode, indicating their origins of remote sources. In the dust period, some water-soluble ions increased in PM10, but the main components in PM10 were SO42−,NO3− and NH4+. At last, we assessed the sources of dusts by analyzing synoptic situation and back trajectories of air mass in Guangzhou, and demonstrated that the main source of the dust storm was from Mongolia.

Influence of Mode of Delivery on Children’s Attention Deficit Hyperactivity Disorder and Childhood Intelligence

Min Xu,Xuemei Yu,Benjie Fan,Guimei Li,Xinxin Ji 대한신경정신의학회 2023 PSYCHIATRY INVESTIGATION Vol.20 No.8

Objective To investigate whether differences exist in attention deficit hyperactivity disorder (ADHD) and intelligence between children born by cesarean delivery and those born by vaginal delivery.Methods This retrospective study included singleton children that were born between January 2013 and December 2014. The Chinese version of the Conners’ Parent Rating Scale–Revised (CPRS-48) was required on the probability of psychological and behavioral problems. The China–Wechsler Intelligence Scale for Children (C-WIRS) was used for evaluation of crystallized intelligence and Raven’s Standard Progressive Matrices for evaluation of fluid intelligence.Results A total of 10,568 valid questionnaires were obtained. CPRS-48 ADHD index and detection rate were higher in cesarean delivery group than those in vaginal delivery group. Cesarean delivery groups had a lower performance intelligence quotient score according to C-WISC.Conclusion Children born by cesarean delivery were more likely to have a risk of ADHD and a lower performance intelligence quotient compared with those born by vaginal delivery.

A Self-adaptive Spectral Clustering Based on Geodesic Distance and Shared Nearest Neighbors

Chunmiao Yuan,Kaixiang Fan,Xuemei Sun 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.4

Spectral clustering is a method of subspace clustering which is suitable for the data of any shape and converges to global optimal solution. By combining concepts of shared nearest neighbors and geodesic distance with spectral clustering, a self-adaptive spectral clustering based on geodesic distance and shared nearest neighbors was proposed. Experiments show that the improved spectral clustering algorithm can fully take into account the information of neighbors, but also measure the exact distance and better process the geodetic data.

Comprehensive Analysis of Gut Microbiota Alteration in the Patients and Animal Models with Polycystic Ovary Syndrome

Zhou Jing,Qiu Xuemei,Chen Xuejing,Ma Sihan,Chen Zhaoyang,Wang Ruzhe,Tian Ying,Jiang Yufan,Fan Li,Wang Jingjie 한국미생물학회 2023 The journal of microbiology Vol.61 No.9

Polycystic ovary syndrome (PCOS) is a common disease of endocrine–metabolic disorder, and its etiology remains largely unknown. The gut microbiota is possibly involved in PCOS, while the association remains unclear. The comprehensive analysis combining gut microbiota with PCOS typical symptoms was performed to analyze the role of gut microbiota in PCOS in this study. The clinical patients and letrozole-induced animal models were determined on PCOS indexes and gut microbiota, and fecal microbiota transplantation (FMT) was conducted. Results indicated that the animal models displayed typical PCOS symptoms, including disordered estrous cycles, elevated testosterone levels, and ovarian morphological change; meanwhile, the symptoms were improved after FMT. Furthermore, the microbial diversity exhibited disordered, and the abundance of the genus Ruminococcus and Lactobacillus showed a consistent trend in PCOS rats and patients. The microbiota diversity and several key genera were restored subjected to FMT, and correlation analysis also supported relevant conclusions. Moreover, LEfSe analysis showed that Gemmiger, Flexispira, and Eubacterium were overrepresented in PCOS groups. Overall, the results indicate the involvement of gut microbiota in PCOS and its possible alleviation of endocrinal and reproductive dysfunctions through several special bacteria taxa, which can function as the biomarker or potential target for diagnosis and treatment. These results can provide the new insights for treatment and prevention strategies of PCOS.

Impact of Refined Land Surface Properties on the Simulation of a Heavy Convective Rainfall Process in the Pearl River Delta Region, China

Ming Chang,Shaofen Fan,Qi Fan,Weihua Chen,Yiqiang Zhang,Yu Wang,Xuemei Wang 한국기상학회 2014 Asia-Pacific Journal of Atmospheric Sciences Vol.50 No.5

The location and occurrence time of convective rainfallshave attracted great public concern as they can lead to terribledisasters. However, the simulation results of convective rainfalls inthe Pearl River Delta region often show significant discrepanciesfrom the observations. One of the major causes lies in the inaccurategeographic distribution of land surface properties used in the modelsimulation of the heavy precipitation. In this study, we replaced thedefault soil and vegetation datasets of Weather Research andForecasting (WRF) model with two refined datasets, i.e. theGlobCover 2009 (GLC2009) land cover map and the HarmonizedWorld Soil Database (HWSD) soil texture, to investigate the impactof vegetation and soil on the rainfall patterns. The result showed thatthe simulation patterns of convective rainfalls obtained from thecoupled refined datasets are more consistent with the observationsthan those obtained from the default ones. By using the coupledrefined land surface datasets, the overlap ratio of high precipitationdistricts reached 36.3% with a variance of 28.5 km from theobserved maximum rainfall position, while those of the defaultUnited States Geological Survey (USGS) dataset and ModerateResolution Imaging Spectroradiometer (MODIS) dataset are 17.0%/32.8 km and 24.9%/49.0 km, respectively. The simulated totalrainfall amount and occurrence time using the coupled refineddatasets are the closest to the observed peak values. In addition, theHWSD soil data has improved the accuracy of the simulatedprecipitation amount, and the GLC2009 land cover data also didbetter in catching the early peak time.

Probing the Key Binding Sequence and Improvement of the Stability of a β-Bungarotoxin-binding Aptamer in Snake Venom

Fengping Ye,Qili Mi,Ning Zhang,Xuemei Li,Jing Yu,Zhongping Gao,Ying Zheng,Quanshui Fan,Jie Wang,Jinglin Wang 대한화학회 2016 Bulletin of the Korean Chemical Society Vol.37 No.5

Chemical modifications of the nucleotides can improve the stability of aptamers against enzyme degradation in serum, but it is not clear whether these methods are effective in snake venom. In this study, a DNA aptamer, βB-1, which specifically recognize β-bungarotoxin and Bungarus multicinctus venom was chosen, and the key binding sequence of the aptamer was determined. Based on the secondary structure of the truncated aptamer, locked nucleic acids and 2′-O-methyl nucleotides were applied to modify the stem and loop sequences, respectively. In addition, a 3′-3′-thymidine cap was also adopted to block the 3′ end. It was shown that these chemical modifications can all enhance the stability of the aptamer in snake venom. Simultaneously, modified aptamer with the above modifications in one sequence exhibited a significantly elevated biostability, with the half-life improved from several minutes to 210 min while maintaining its binding affinity to the target.

Quality evaluation of different varieties of dry red wine based on nuclear magnetic resonance metabolomics

Hu Boran,Gao Jin,Xu Shaochen,Zhu Jiangyu,Fan Xuemei,Zhou Xiaoyan 한국응용생명화학회 2020 Applied Biological Chemistry (Appl Biol Chem) Vol.63 No.3

The metabolites that provide the aroma and flavor to wine are the products of several influences, such as grape cultivar, geographic location and associated environmental features, viticultural practices, and vinification techniques, which are central to production protocols, quality evaluation and development of wine regions. Accordingly, we initiated the requisite studies to investigate the differences in the dry red wine metabolites of different grape varieties. The proton-nuclear magnetic resonance technique (1H-NMR) combined with multivariate statistical analysis was used to investigate the changes of metabolite levels in Cabernet Sauvignon, Merlot and Cabernet Gernischt dry red wines vinified in Changli, Hebei province, China, in 2017. The results showed that the types of metabolites in different varieties of dry red wines were similar, but the content was significantly different. The main contributors to the differences in Cabernet Sauvignon, Merlot and Cabernet Gernischt dry red wines were ethyl acetate, lactic acid, alanine, succinic acid, proline, malic acid, and gallic acid, indicating 1H-NMR method combined with multivariate statistical analysis can distinguish these three types of dry red wines from each other. It provides a benchmark for further comparative study on wine quality and the verification of wine authenticity.