Influence of the River Ceasing on Wetland Environment in the Yellow River Delta

Chen, Weifeng,Shi, Yanxi,Mi, Qinghua,Ann, Seoung-Won 한국환경과학회 2003 한국환경과학회지 Vol.12 No.2

The yellow River delta is an important region where coastal and newly formed wetlands distribute in north Chine. Based on satellite remote sensing images and GIS thchniques, this paper tends to delineate the dynamic changes of newly formed wetland in the Yellow River mouth from 1986.5 To 1996.10. Our results show that the newly formed wetland increased by 24.9 ㎢ per year. Before 1990.1 and it decreased by 2.40 ㎢ per year after that. The northern and southwestern parts of the Yellow River mouth are main positions of decrease and the southern and the estuary parts are main positions of increase. The advancing rate of river mouth extending into the Bo Sea is decreasing obviously. The reason for that is the decreasing of water and sediments in the Yellow River, Which caused by the increasing use of water and soil conservation on upper reath.

Emerging roles of centromeric RNAs in centromere formation and function

Qian Liu,Yang Liu,Qinghua Shi,Handong Su,Chunhui Wang,James A. Birchler,Fangpu Han 한국유전학회 2021 Genes & Genomics Vol.43 No.3

Background Centromeres are specialized chromosomal domains involved in kinetochore formation and faithful chromosome segregation. Despite a high level of functional conservation, centromeres are not identifed by DNA sequences, but by epigenetic means. Universally, centromeres are typically formed on highly repetitive DNA, which were previously considered to be silent. However, recent studies have shown that transcription occurs in this region, known as centromeric-derived RNAs (cenRNAs). CenRNAs that contribute to fundamental aspects of centromere function have been recently investigated in detail. However, the distribution, behavior and contributions of centromeric transcripts are still poorly understood. Objective The aim of this article is to provide an overview of the roles of cenRNAs in centromere formation and function. Methods We describe the structure and DNA sequence of centromere from yeast to human. In addition, we briefy introduce the roles of cenRNAs in centromere formation and function, kinetochore structure, accurate chromosome segregation, and pericentromeric heterochromatin assembly. Centromeric circular RNAs (circRNAs) and R-loops are rising stars in centromere function. CircRNAs have been successfully identifed in various species with the assistance of high-throughput sequencing and novel computational approaches for non-polyadenylated RNA transcripts. Centromeric R-loops can be identifed by the single-strand DNA ligation-based library preparation technique. But the molecular features and function of these centromeric R-loops and circRNAs are still being investigated. Conclusion In this review, we summarize recent fndings on the epigenetic regulation of cenRNAs across species, which would provide useful information about cenRNAs and interesting hints for further studies.

Residual Surface Topology Modeling and Simulation Analysis for Micro-Machined Nozzle

Yukui Cai,Zhan-qiang Liu,Zhen-yu Shi,Qinghua Song,Yi Wang 한국정밀공학회 2015 International Journal of Precision Engineering and Vol. No.

The performance of the micro nozzle is determined primarily by its machined surface topology. A circular cross-section micro-Lavalnozzle is modeled and studied by using numerical simulation in this paper. The geometry of residual height and residual area ofmachined nozzle surface with flat-end milling cutter and ball-end milling cutter are created. It is found that the ball end milling cutterwith large diameter is better than the flat one for nozzle finishing operations. The nozzle velocity performance is also revealed in thisresearch. When residual height increased from 0.6 μm to 9.6 μm for nozzle with throat diameter less than 2 mm, the maximum outletvelocity of nozzle reduced gradually. The maximum outlet velocity of nozzle remains stable for the nozzle with throat diameter greaterthan 2 mm. The results show that the maximum outlet velocity of nozzle significantly reduces with throat diameter decreasing underconstant residual height. Based on the analysis about velocity boundary layer, when residual height changing from 0.6 μm to 9.6 μm,the nozzle with throat diameter is 1 mm, has the boundary layer thickness ranging from 5% to 14% of outlet radius.

Distribution Characteristic and Assessment of Soil Organic Matter, Nitrogen and Phosphorus in Soils of New born River Mouth Wetlands

Chen, Weifeng,Ann, Seoung-Won,Shi, Yanxi,Mi, QingHua 한국환경과학회 2003 한국환경과학회지 Vol.12 No.2

The paper investigates preliminarily spatial distribution soil organic matter (SOM), nitrogen (N) and phosphorus (O) and its environmental influence in wetland soil of different vegetation landscape in the Yellow River Mouth. The result shows the SOM and total nitrogen (TN), efficient N, efficient P in top later soils of different vegetation district have signficantly different content, The SOM is show as Calamagrostis epigeios wetlands >Phragmites cmmunis wetlands >Tamarix chinensi wetlands above tidal >Suaeda salsa wetlands in high tidal >Tamarix chinensi wetlands in high tidal >tidal flats, the arrange of the TN and efficient N content is the same except that the content in Suaeda salsa wetlands in high tidal is heavier than Tamarix chinensi wetlands in high tidal. In different vegetation landscape wetland types the vertical change of soil nutrients are obvious except for P, gradually decrease from the upper to the lower. This case reflects the function of the vegetation on the wetland development of soil, and proves the wetland soil has the characteristic of new born and bad degree of development, SOM, TM, efficient N and efficient P content in wetland soils have significantly positive correlation, but TP have no correlation with them but efficient P. The contents of TN in wetland soils range from 58∼1480㎎/㎏, total average content 408 ㎎/㎏, average content of above 30 cm is 625 ㎎/㎏. The range of TP content in the soil is 372∼1042㎎/㎏, total average is 569 ㎎/㎏, average content of above 20 cm is 611㎎/㎏. According the P it occurs mainly as calcium phosphates, and the validity is lower, therefore, N and P in the new born wetlands cannot produce serious impact on the environments at present.

Artificial Intelligence in the Prediction of Gastrointestinal Stromal Tumors on Endoscopic Ultrasonography Images: Development, Validation and Comparison with Endosonographers

Lu Yi,Wu Jiachuan,Hu Minhui,Zhong Qinghua,Er Limian,Shi Huihui,Cheng Weihui,Chen Ke,Liu Yuan,Qiu Bingfeng,Xu Qiancheng,Lai Guangshun,Wang Yufeng,Luo Yuxuan,Mu Jinbao,Zhang Wenjie,Zhi Min,Sun Jiachen 거트앤리버 소화기연관학회협의회 2023 Gut and Liver Vol.17 No.6

Background/Aims: The accuracy of endosonographers in diagnosing gastric subepithelial lesions (SELs) using endoscopic ultrasonography (EUS) is influenced by experience and subjectivity. Artificial intelligence (AI) has achieved remarkable development in this field. This study aimed to develop an AI-based EUS diagnostic model for the diagnosis of SELs, and evaluated its efficacy with external validation. Methods: We developed the EUS-AI model with ResNeSt50 using EUS images from two hospitals to predict the histopathology of the gastric SELs originating from muscularis propria. The diagnostic performance of the model was also validated using EUS images obtained from four other hospitals. Results: A total of 2,057 images from 367 patients (375 SELs) were chosen to build the models, and 914 images from 106 patients (108 SELs) were chosen for external validation. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the model for differentiating gastrointestinal stromal tumors (GISTs) and non-GISTs in the external validation sets by images were 82.01%, 68.22%, 86.77%, 59.86%, and 78.12%, respectively. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy in the external validation set by tumors were 83.75%, 71.43%, 89.33%, 60.61%, and 80.56%, respectively. The EUS-AI model showed better performance (especially specificity) than some endosonographers. The model helped improve the sensitivity, specificity, and accuracy of certain endosonographers. Conclusions: We developed an EUS-AI model to classify gastric SELs originating from muscularis propria into GISTs and non-GISTs with good accuracy. The model may help improve the diagnostic performance of endosonographers. Further work is required to develop a multi-modal EUS-AI system.

Temporal and Spatial Change in Microbial Diversity in New-developed Wetland Soil Covered by Tamarix chinesis Community in Chinese Yellow River Delta

Chen, WeiFeng,Ann, Seoung-Won,Kim, Hong-Nam,Shi, Yanxi,Mi, Qinghua 한국환경과학회 2005 한국환경과학회지 Vol.14 No.4

Soil samples were collected from new-developed wetland soil ecosystem of Tamarix chinesis plantation in Chinese Yellow River Delta in different months of 2003. Soil characteristics, temporal change and spatial distribution of microbial community composition and their relationship with nitrogen turnover and circling were investigated in order to analyze and characterize the role of microbial diversity and functioning in the specific soil ecosystem. The result showed that the total population of microbial community in the studied soil was considerably low, compared with common natural ecosystem. The amount of microorganism followed as the order: bacteria> actinomycetes>fungi. Amount of actinomycetes were higher by far than that of fungi. Microbial population remarkably varied in different months. Microbial population of three species in top horizon was corrected to that in deep horizon. Obvious rhizosphere effect was observed and microbial population was significantly higher in rhizosphere than other soils due to vegetation growth, root exudation, and cumulative dead fine roots. Our results demonstrate that microbial diversity is low, while is dominated by specific community in the wetland ecosystem of Tamarix chinesi.

A Novel APTX Variant and Ataxia with Oculomotor Apraxia Type 1

Humera Manzoor,Ihtisham Bukhari,Muhammad Wajid,Yuanwei Zhang,Huan Zhang,Norbert Brüggemann,Christine Klein,Qinghua Shi,Sadaf Naz 대한신경과학회 2017 Journal of Clinical Neurology Vol.13 No.3

Lineage conversion of mouse fibroblasts to pancreatic α-cells

Lijian Hui,Liangliang Sun,Beige Jiang,Limei Li,Jin Cen,Xiaotao Chen,Zhaoyun Zhang,Qinghua Wang,Xin Cheng,Yongquan Shi,Lijian Hui 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

α-cells, which synthesize glucagon, also support β-cell survival and have the capacity to transdifferentiate into β-cells. However, the role of α-cells in pathological conditions and their putative clinical applications remain elusive due in large part to the lack of mature α-cells. Here, we present a new technique to generate functional α-like cells. α-like cells (iAlpha cells) were generated from mouse fibroblasts by transduction of transcription factors, including Hhex, Foxa3, Gata4, Pdx1 and Pax4, which induce α-cell-specific gene expression and glucagon secretion in response to KCl and Arg stimulation. The cell functions in vivo and in vitro were evaluated. Lineage-specific and functional-related gene expression was tested by realtime PCR, insulin tolerance test (ITT), glucose tolerance test (GTT), Ki67 and glucagon immunohistochemistry analysis were done in iAlpha cells transplanted nude mice. iAlpha cells possess α-cell function in vitro and alter blood glucose levels in vivo. Transplantation of iAlpha cells into nude mice resulted in insulin resistance and increased β-cell proliferation. Taken together, we present a novel strategy to generate functional α-like cells for the purposes of disease modeling and regenerative medicine.