Domain Switching and Crack Propagation of BaTiO3 Single Crystal in Different Environments

( Ke Wei Gao ),( Xian Wu Zhao ),( Rui Min Wang ),( Li Jie Qiao ),( Wu Yang Chu ) 한국부식방식학회 2008 Corrosion Science and Technology Vol.7 No.6

Wavelet Multiresolution Complex Network for Analyzing Multivariate Nonlinear Time Series

Gao, Zhong-Ke,Li, Shan,Dang, Wei-Dong,Yang, Yu-Xuan,Do, Younghae,Grebogi, Celso World Scientific 2017 International journal of bifurcation and chaos in Vol.27 No.8

<P>Characterizing complicated behavior from time series constitutes a fundamental problem of continuing interest and it has attracted a great deal of attention from a wide variety of fields on account of its significant importance. We in this paper propose a novel wavelet multiresolution complex network (WMCN) for analyzing multivariate nonlinear time series. In particular, we first employ wavelet multiresolution decomposition to obtain the wavelet coefficients series at different resolutions for each time series. We then infer the complex network by regarding each time series as a node and determining the connections in terms of the distance among the feature vectors extracted from wavelet coefficients series. We apply our method to analyze the multivariate nonlinear time series from our oil-water two-phase flow experiment. We construct various wavelet multiresolution complex networks and use the weighted average clustering coefficient and the weighted average shortest path length to characterize the nonlinear dynamical behavior underlying the derived networks. In addition, we calculate the permutation entropy to support the findings from our network analysis. Our results suggest that our method allows characterizing the nonlinear flow behavior underlying the transitions of oil-water flows.</P>

EARLY CRETACEOUS BIRDS AND PTEROSAURS FROM THE SINUIJU SERIES, AND GEOGRAPHIC EXTENSION OF THE JEHOL BIOTA INTO THE KOREAN PENINSULA

Ke-Qin Gao,Quanguo Ll,MINGRUI WEI,HyonUk Pak,Insop Pak 한국고생물학회 2009 고생물학회지 Vol.25 No.1

The Lower Cretaceous Sinuiju Series of the Jasong Supergroup (=Jasong System of Pak and Kim, 1996) developed in the Amnok River Basin, North Korea, has yielded a potentially important vertebrate fauna, the taxonomic components of which are closely similar to those of the Jehol Biota best known from the Yixian and Chiufotang (=Jiufotang) formations in western Liaoning province, China (Chang et al., 2003; Zhou et al., 2003). The fossil-bearing beds of the Sinuiju Series consist of lacustrine fine-grained sandstones, mudstones, tuffaceous shales and andesites with a total thickness of over 2500 meters (Pak and Kim, 1996). Stratigraphically, the Sinuiju Series rests unconformably on top of Paleo-proterozoic metamorphic rocks, and underlies the Cretaceous Taebo Supergroup and Palaeogene strata. The age of the Sinuiju Series was thought to be Late Jurassic (Pak and Kim, 1996), but the strata contain the characteristic Eosestheria-Ephemeropsis-Lycoptera complex of the Jehol Biota, supporting an Early Cretaceous age of the Series (see also Lee et al., 2001). Accordingly, the Sinuiju fauna signifies the geographic extension of the Jehol Biota from northeast China into the Korean Peninsula. Vertebrate fossils were found at a road-cut approximately six kilometers south of the city of Sinuiju (Figure 1). The fossil specimens already excavated from this site include Lycoptera and sturgeon fishes, anuran amphibians, several birds, possible theropod dinosaurs, and pterosaurs; none of these have been described in scientific publication, and the taxonomic status has remained uncertain ever since their discovery. Most of the fossils are preserved as dorso-ventral compressions as commonly seen in the Liaoning beds, but occur in dark shales that denote a slightly different depositional environment than the Yixian and Chiufotang formations in western Liaoning, China.

Cloning and analysis of b-amyrin synthase gene in Bupleurum chinense

Ke Gao,Su-rui Wu,Ling Wang,Yan-hong Xu,Jian-he Wei,Chun Sui 한국유전학회 2015 Genes & Genomics Vol.37 No.9

Bupleurum chinense DC. is one of the source plants of a well-known crude drug, Chai hu (Radix Bupleuri), producing triterpenoid saponins (saikosaponins) with a wide-spectrum of pharmacological applications. The biosynthesis of triterpenoid saponins involved with the cyclizing of the precursor 2,3-oxidosqualene to produce the first committed triterpene b-amyrin catalyzed by b-amyrin synthase (b-AS), whereafter diverse of triterpenoid saponins was biosynthesized. In addition, 2,3-oxidosqualene could be catalyzed by cycloartenol synthase directing to the synthesis of phytosterol. b-AS was thus defined as an important branch point between primary and secondary metabolisms, and may play a regulating role in the control of triterpenoid saponins biosynthesis. In this study, the promoter and protein-encoding regions of a b-AS gene (designated bcAS1) were isolated by genome walking and PCR from B. chinense. Several important cis-acting elements for gene regulation were identified within the promoter region including light-responsive, hormoneresponsive and various other stress-related elements. Approximate 0.8 kb fragment on upstream of ATG start codon of bcAS1 was sub-cloned into pAN580 vector to replace the 35S promoter driving the expression of green fluorescent protein (GFP) gene. The promoter activity was detected by transient expression in onion epidermis cells by the expression of GFP. Approximately 6 kb length of bcAS1 gene was cloned, containing 18 exons and 17 introns. Although a dozen of b-AS cDNA was isolated, seldom the promoter and gene of it was reported. This work was a valuable foundation for further studies on the regulatory role of b-AS in biosynthesis of saikosaponins.

Environmental fatigue correction factor model for domestic nuclear-grade low-alloy steel

Gao, Jun,Liu, Chang,Tan, Jibo,Zhang, Ziyu,Wu, Xinqiang,Han, En-Hou,Shen, Rui,Wang, Bingxi,Ke, Wei Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.8

Low cycle fatigue behaviors of SA508-3 low-alloy steel were investigated in room-temperature air, high-temperature air and in light water reactor (LWR) water environments. The fatigue mean curve and design curve for the low-alloy steel are developed based on the fatigue data in room-temperature and high-temperature air. The environmental fatigue model for low-alloy steel is developed by the environmental fatigue correction factor (F_en) methodology based on the fatigue data in LWR water environments with the consideration of effects of strain rate, temperature, and dissolved oxygen concentration on the fatigue life.

Exercise Reduces Airway Smooth Muscle Contraction in Asthmatic Rats via Inhibition of IL-4 Secretion and Store-Operated Ca2+ Entry Pathway

Huang Jun-Hao,Gao Hui-Wen,Gao Dong-Dong,Yang Wei-Yue,Zhao Meng-Ke,Shen Bing,Hu Min 대한천식알레르기학회 2023 Allergy, Asthma & Immunology Research Vol.15 No.3

Purpose: Increased evidence has shown that aerobic exercise reduces airway hyperresponsiveness in asthmatic individuals. However, the underlying mechanisms of action remain elusive. This study aimed to investigate the effect of exercise on airway smooth muscle (ASM) contractile function in asthmatic rats, and uncover the possible involvement of interleukin 4 (IL-4) and the store-operated Ca2+ entry (SOCE) pathway. Methods: In this study, chicken ovalbumin was used to induce asthma in male Sprague-Dawley rats. The exercise group received moderate-intensity aerobic exercise training for 4 weeks. IL-4 concentrations in bronchoalveolar lavage fluid (BALF) samples were evaluated by enzyme linked immunosorbent assay. The contractile function of the ASM was investigated using tracheal ring tension experiments and intracellular Ca2+ imaging techniques. Western blot analysis was used to evaluate expression levels of calcium-release activated calcium (CRAC) channel protein (Orai) and stromal interaction molecule 1 (STIM1) in ASM. Results: Our data showed that the carbachol-stimulated, SOCE-mediated contraction of rat ASM was significantly increased in asthmatic rats, which could be abolished by exercise. Pharmacological studies revealed that GSK5498A and BTP-2, selective blockers of CRAC channels significantly inhibited SOCE-induced ASM contraction. In addition, exercise inhibited the up-regulation of IL-4 in BALF as well as STIM1 and Orai expression in the ASM of asthmatic rats. In line with these observations, we demonstrated that pretreatment of the ASM with IL-4 up-regulated the expression level of STIM1, Orai1 and Orai2, thereby promoting SOCE-mediated ASM contraction. Conclusions: The data in this study reveal that aerobic exercise may improve the ASM contractile function in asthmatic rats by inhibiting IL-4 secretion and by down-regulating the expression of STIM1, Orai1 and Orai2, thus decreasing excessive SOCE-mediated ASM contraction in asthmatic rats.

Response of Saccharomyces cerevisiae to Ethanol Stress Involves Actions of Protein Asrlp

( Jun Mei Ding ),( Xiao Wei Huang ),( Na Zhao ),( Feng Gao ),( Qian Lu ),( Ke Qin Zhang ) 한국미생물 · 생명공학회 2010 Journal of microbiology and biotechnology Vol.20 No.12

During the fermentation process of Saccharomyces cerevisiae, yeast cells must rapidly respond to a wide variety of external stresses in order to survive the constantly changing environment, including ethanol stress. The accumulation of ethanol can severely inhibit cell growth activity and productivity. Thus, the response to changing ethanol concentrations is one of the most important stress reactions in S. cerevisiae and worthy of thorough investigation. Therefore, this study examined the relationship between ethanol tolerance in S. cerevisiae and a unique protein called alcohol sensitive RING/PHD finger 1 protein (Asr1p). A real-time PCR showed that upon exposure to 8% ethanol, the expression of Asr1 was continuously enhanced, reaching a peak 2 h after stimulation. This result was confirmed by monitoring the fluorescence levels using a strain with a green fluorescent protein tagged to the C-terminal of Asr1p. The fluorescent microscopy also revealed a change in the subcellular localization before and after stimulation. Furthermore, the disruption of the Asr1 gene resulted in hypersensitivity on the medium containing ethanol, when compared with the wild-type strain. Thus, when taken together, the present results suggest that Asr1 is involved in the response to ethanol stress in the yeast S. cerevisiae.

The Pathway and Regulation of Salicylic Acid Biosynthesis in Probenazole-Treated Arabidopsis

Jin Yu,Jiong Gao,Xiao Yan Wang,Qiang Wei,Li Feng Yang,Kai Qiu,Ben Ke Kuai 한국식물학회 2010 Journal of Plant Biology Vol.53 No.6

Probenazole (PBZ; 3-allyloxy-1,2-benzisothiazole-1,1-dioxide) is a highly effective chemical inducer of systemic-acquired resistance (SAR). It has been used widely to protect rice plants against the rice blast fungus Magnaporthe grisea. Previous studies have shown that PBZ induces SAR through enhanced accumulation of salicylic acid (SA). Plants synthesize SA by either a pathway that uses phenylalanine as substrate or another that involves isochorismate. To clarify how SA is produced in PBZ-treated Arabidopsis, we examined the expression patterns and enzyme activities of phenylalanine ammonia lyase (PAL) and isochorismate synthase (ICS), which are the main components of the phenylalanine and isochorismate pathways, respectively. PBZ exposure significantly improved the accumulation of SA and increased ICS activity. In the sid2–2 mutant, which has a defect in ICS1,PBZ had no effect on the level of endogenous SA or activity of ICS. In contrast, PAL activity and the expression of most PAL genes were down-regulated by such treatment in wild-type plants. These results suggest that SA is mainly synthesized via the ICS-mediated pathway in Arabidopsis.

Serum miR-21 Expression in Human Esophageal Squamous Cell Carcinomas

Cai, Er-Hui,Gao, Yong-Xin,Wei, Zhong-Zhi,Chen, Wei-Ying,Yu, Ping,Li, Ke Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.4

To investigate the relationship between serum miRNA-21 (miR-21) expression in esophageal squamous cell carcinomas (ESCCs) and its clinicopathologic features, a 1:1 matched case-control study including 21 patients with ESCC and 21 age- and gender-matched healthy controls was carried out. Serum specimens were taken from all subjects. Total RNA was extracted and the stem-loop real time polymerase chain reaction was used to measure serum miR-21 in both groups. Clinical parameters were assessed to determine associations with serum miR-21 concentrations. Serum miR-21 expression in ESCC samples was significantly higher than in paired cancer-free samples (P<0.05). Metastasis was associated with mir-21 expression in serum (P<0.05), ESCC patients with metastasis having 8.4-fold higher serum miR-21 concentrations than healthy controls. There were no statistically significant associations between miR-21 expression and clinicopathologic parameters, such as gender (P>0.05), age (P>0.05), tumor location (P>0.05), cell differentiation (P>0.05), TNM staging (P>0.05), whether chemo/radiotherapy had been administered (P>0.05), or whether surgery had been performed (P>0.05). These findings suggest that the detection of microRNA-21 in serum might serve as a new tumor biomarker in diagnosis and assessment of prognosis of ESCCs.

Research on Influence of Matrix Component on the Mechanical Behavior of Multiaxial Warp-knitted Composites

Jiawei Chen,Xiaoping Gao,Ke Zhao,Wei Wu 한국섬유공학회 2022 Fibers and polymers Vol.23 No.11

The mass ratio of curing agent to epoxy resin is one of the important factors affecting the behavior of matrix andcomposites. In this paper, the solution of curing agent to epoxy resin with different mass ratio (0.25, 0.30, 0.35 and 0.40) wasselected as matrix, quadriaxial warp-knitted fabric was selected as reinforcement, and the composites were manufactured byapplying vacuum assisted film infusion. Then the tensile and bending behavior of the composites was experimentallyinvestigated, and the curing degree and failure mechanism of the composites were analyzed with respect to thethermodynamic properties and the microscopic failure morphologies. The optimal mass ratio was obtained by applyingnonlinear fitting and verified by experiment, and a mathematical model was derived to predict the relationship between thestrength and the mass ratio. The results showed that the thermal stability, curing degree, tensile and bending strength of thespecimens increase firstly and then decrease with increase of the mass ratio. According to the tensile and bending strengthresults, the optimum mass ratio were obtained as 0.31 and 0.33 by applying nonlinear fitting to the experiment data. Theresults could lay a theoretical foundation for optimizing the mass ratio of matrix components, and improve the strength ofcomposites.