Formation Mechanism and Control Measures of Sliding Surface about Bedding Slope Containing Weak Interlayer

Tao Wang,Hongbao Zhao,Yihong Liu,Shaoqiang Liu,Rui Liu 대한토목학회 2020 KSCE JOURNAL OF CIVIL ENGINEERING Vol.24 No.8

During the mining process of Hami open-pit coal mine, a large number of cracks appeared on the ground surface near the top of the end slope, which affected the stability of the slope and the subsequent safe mining of resources. By analyzing the deformation of rock stratum, the position of weak interlayer in the slope was determined. Considering the rock mass with weak interlayer as a complete mechanical system, the mechanical model of the rock mass system with weak interlayer was established, and the evaluation index of rock failure degree before slope instability was proposed. The failure mode of slope with weak interlayer is as follows: sliding failure-cutting layer failure-tension failure. The safety factor of slope decreases first and then increases with the increase of the depth of the weak interlayer, and gradually decreases with the increase of the inclination of the weak interlayer. The pressing foot of slope can be used in landslide control of slope with weak interlayers, and the optimal pressing foot solution to ensure the safe mining of final slope coal resources was determined to be a pressing foot height of 35 m and pressing foot width of 20 m.

A Comparative Analysis of Government Responses to COVID-19 in the United States, China, and South Korea: Lessons from the Early Stage of the Pandemic

Haeil Jung(Haeil Jung),Ki Woong Cho(Ki Woong Cho),Kaifeng Yang(Kaifeng Yang),Sun Young Kim(Sun Young Kim),Yihong Liu(Yihong Liu) 한국학술연구원 2023 Korea Observer Vol.54 No.1

COVID-19 has spread quickly worldwide, presenting unprecedented challenges to countries all over the globe. To understand how different countries have responded to COVID-19 during the early stage of the outbreak, we develop a comprehensive research framework drawing on the literature on wicked problems. Specifically, we comparatively investigate the government responses of the United States, China, and South Korea and examine why and how these countries have adopted and implemented various strategies authoritative, collaborative, and competitive — —depending on their policy environment. Although scholars have argued that collaborative strategies are the preferred approach to dealing with wicked problems, it is found that the most applicable, implementable, and effective strategies vary according to the country's cultural, economic, and political contexts. In addition, the urgency and timing of the crisis may affect the choice of appropriate strategies. Our findings can provide lessons for public administration and policy to cope with other wicked problems.

Heat Shock Protein 90 Inhibitor Decreases Collagen Synthesis of Keloid Fibroblasts and Attenuates the Extracellular Matrix on the Keloid Spheroid Model

Liu, Qingliang,Wang, Xiaojun,Jia, Yihong Williams & Wilkins 2016 Plastic and reconstructive surgery Vol.137 No.4

Over-expression of GmMYB39 leads to an inhibition of the isoflavonoid biosynthesis in soybean (Glycine max. L)

Liu, Xiaoqing,Yuan, Lingling,Xu, Ling,Xu, Zhaolong,Huang, Yihong,He, Xiaolan,Ma, Hongxiang,Yi, Jinxin,Zhang, Dayong 한국식물생명공학회 2013 Plant biotechnology reports Vol.7 No.4

In this paper, we isolated and characterized a gene encoding the soybean MYB transcription factor, GmMYB39 (Accession No: XM_003538605). Analysis of the deduced amino acid sequence revealed that GmMYB39 contained N-terminal R2R3 repeats that corresponded to the DNA-binding domain of plant MYB-type proteins, which were highly conserved among the R2R3-MYB proteins. The detailed expression pattern of GmMYB39 in various tissues of soybean was investigated by quantitative RT-PCR. The transcript level was found to be higher in flowers than in other examined organs. In contrast, the GmMYB39 expression level was relatively weak in the pod. The GmMYB39-GFP fusion protein was found to localize in the nucleus of Arabidopsis mesophyll protoplasts. Over-expression of GmMYB39 in hairy roots resulted in a significant reduction of the transcript levels of PAL, C4H, CHS, 4CL, and CHR. Whereas, the IFS transcript level was slightly but not significantly increased, and no significant change in CHI expression was observed between over-expression and control roots. The repressing effect on expression of CHS was further supported by the results from co-transfection assays of CHS promoter (reporter) and GmMYB39 (effector) in soybean. Compared to the control (only with the reporter construct), a significant decrease in the GUS activity was observed in soybean hairy roots with both effector and reporter constructs. Furthermore, an ultimate decrease in isoflavonoids contents coincided with the decrease in the transcript levels of PAL, C4H, CHS, 4CL, and CHR. Overall, the results suggest that GmMYB39 plays an inhibiting role in regulating the isoflavonoid biosynthesis in soybean.

Cloning and Biochemical Characterization of a Hyaluronate Lyase from Bacillus sp. CQMU-D

Wang Lu,Liu Qianqian,Gong Xue,Jian Wenwen,Cui Yihong,Jia Qianying,Zhang Jibei,Zhang Yi,Guo Yanan,Lu He,Tu Zeng 한국미생물·생명공학회 2023 Journal of microbiology and biotechnology Vol.33 No.2

Hyaluronidase (HAase) can enhance drug diffusion and dissipate edema by degrading hyaluronic acid (HA) in the extracellular matrix into unsaturated HA oligosaccharides in mammalian tissues. Microorganisms are recognized as valuable sources of HAase. In this study, a new hyaluronate lyase (HAaseD) from Bacillus sp. CQMU-D was expressed in Escherichia coli BL21, purified, and characterized. The results showed that HAaseD belonged to the polysaccharide lyase (PL) 8 family and had a molecular weight of 123 kDa. HAaseD could degrade chondroitin sulfate (CS) -A, CS-B, CSC, and HA, with the highest activity toward HA. The optimum temperature and pH value of HAaseD were 40°C and 7.0, respectively. In addition, HAaseD retained stability in an alkaline environment and displayed higher activity with appropriate concentrations of metal ions. Moreover, HAaseD was an endolytic hyaluronate lyase that could degrade HA to produce unsaturated HA oligosaccharides. Together, our findings indicate that HAaseD from Bacillus sp. CQMU-D is a new hyaluronate lyase and with excellent potential for application in industrial production.

Over-expression of GmMYB39 leads to an inhibition of the isoflavonoid biosynthesis in soybean (Glycine max. L)

Jinxin Yi,Xiaoqing Liu,Lingling Yuan,Ling Xu,Zhaolong Xu,Yihong Huang,Xiaolan He,Hongxiang Ma,Dayong Zhang 한국식물생명공학회 2013 Plant biotechnology reports Vol.7 No.4

In this paper, we isolated and characterized a gene encoding the soybean MYB transcription factor, GmMYB39 (Accession No: XM_003538605). Analysis of the deduced amino acid sequence revealed that GmMYB39 contained N-terminal R2R3 repeats that corresponded to the DNA-binding domain of plant MYB-type proteins, which were highly conserved among the R2R3-MYB proteins. The detailed expression pattern of GmMYB39 in various tissues of soybean was investigated by quantitative RT-PCR. The transcript level was found to be higher in flowers than in other examined organs. In contrast, the GmMYB39 expression level was relatively weak in the pod. The GmMYB39–GFP fusion protein was found to localize in the nucleus of Arabidopsis mesophyll protoplasts. Over-expression of GmMYB39 in hairy roots resulted in a significant reduction of the transcript levels of PAL, C4H, CHS, 4CL, and CHR. Whereas, the IFS transcript level was slightly but not significantly increased, and no significant change in CHIexpression was observed between over-expression and control roots. The repressing effect on expression of CHS was further supported by the results from co-transfection assays of CHS promoter (reporter) and GmMYB39 (effector) in soybean. Compared to the control (only with the reporter construct), a significant decrease in the GUS activity was observed in soybean hairy roots with both effector and reporter constructs. Furthermore, an ultimate decrease in isoflavonoids contents coincided with the decrease in the transcript levels of PAL, C4H, CHS, 4CL, and CHR. Overall, the results suggest that GmMYB39 plays an inhibiting role in regulating the isoflavonoid biosynthesis in soybean.

Seroprevalence and associated risk factors of pseudorabies in Shandong province of China

Dongfang Hu,Lin Lv,Zhendong Zhang,Yihong Xiao,Sidang Liu 대한수의학회 2016 Journal of Veterinary Science Vol.17 No.3

A cross-sectional serological study was conducted in Shandong province of China to determine the seroprevalence and risk factors associated with seropositivity due to pseudorabies virus (PRV) infection in small- and medium-sized farrow-to-finish herds following outbreaks of variant PRV strains. A total of 6,035 blood samples from 224 randomly selected herds were screened. The results showed that 25.0% of the herds and 56.7% of the serum samples were seropositive for field strains of PRV. Herds consisting of 50–100 breeding sows had higher herd seroprevalence and serum sample seroprevalence than larger herds. Both the highest herd seroprevalence and highest serum sample seroprevalence were observed in western Shandong, followed northern Shandong. Based on univariate analysis, the following risk factors were utilized in subsequent multivariable logistic regression analysis: region, herd size, weight of purchased gilts, and all-in/all-out practice. Upon multivariate analysis, region, herd size, weight of purchased gilts and all-in/all-out practice were significantly associated with PRV herd seropositivity. These findings indicate that we are facing a serious situation in the prevention and control of pseudorabies. The results could help predict the next outbreak and set out control measures.

Establishment and Application of Target Gene Disruption System in Saccharomyces boulardii

Longjiang Wang,Hui Sun,Jie Zhang,Qing Liu,Tiantian Wang,Peipei Chen,Hongmei Li,Yihong Xiao,Fangkun Wang,Xiaomin Zhao 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.1

Saccharomyces boulardii is the best knownprobiotic yeast, widely used as a therapeutic agent for thetreatment or prevention of diarrhea and intestine disorders. In the present work, we established a target gene disruptionsystem for S. boulardii based on the Cre-loxP system usedfor S. cerevisiae and other fungi by screening out selectionmarkers, working out the transformation method, andconstructing essential plasmids for S. boulardii. Theestablished system was successfully applied to the URA3gene disruption and created an ura3 null mutant strain ofS. boulardii. The system can be used for PCR mediatedgene disruption, cloning mediated gene disruption, andreintroduction of the deleted gene back to the mutant. Allthe introduced exogenous DNAs in the gene disruptionprocedures were removed from the final mutant strainexcept the two 34 bp loxP pieces left in deleted gene loci.