Practical Calculation Method for the Short‑Circuit Current of Power Grids with High Temperature Superconducting Fault Current Limiters

Hai‑feng Hong,Meng‑ze Yu,Xiao‑hui Zhang,Jia‑jia Huan,Yu Sui,Xian‑xian Pan 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.2

With the expansion of the power grid scale and the enhancement of network structure interconnection, the short-circuit current of power grids is increasingly close to the upper capacity limit of circuit breakers. The fault current limiter is efective in suppressing the short-circuit current of power grids, and with the mature development of superconducting technology, high-temperature superconducting fault current limiters (HTS-FCLs) have been widely used in power grids. Due to the nonlinear impedance–current characteristic of HTS-FCLs, the traditional short-circuit current calculation method is inapplicable to power grids with HTS-FCLs. First, based on the establishment of the electromechanical transient model and the short-circuit calculation model, the short-circuit current calculation procedure for power grids with HTS-FCLs is proposed. Second, the calculation methods for three-phase and single-phase short-circuit currents at the substation bus in power grids with HTS-FCLs are analyzed. Finally, three-phase and single-phase short-circuit currents at the 500 kV Xijiang substation bus in the Guangdong power grid are calculated as the study case. Simulation results show that compared with the situation where there is no HTS-FCL installed, the short-circuit current on the 500 kV bus decreases from 65.34 to 58.31 kA in terms of the three-phase short-circuit fault, and decreases from 54.56 to 46.62 kA in terms of the single-phase short-circuit fault, thus verifying the efectiveness and practicability of HTS-FCLs in suppressing the short-circuit current, which is signifcant for the safe, stable and reliable operation of the power grid.

Finite element simulation of unconstraint vibration treatment for fatigued copper film

Hai-Meng Zhang,De-Guang Shang,Shuai Lv,Xiao-Dong Liu,Yu Zhang 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.9

In this paper, in order to investigate the residual strain relief in the fatigued copper film with a thickness of 33 μm, an unconstraint vibration treatment process was simulated by finite element (FE) method. The experimental processes, including fatigue and unconstraint vibration processes, were simulated. The fatigue process for the original specimen and the vibration process for the damaged specimen were analyzed by the static and transient dynamic analysis, respectively. The simulation results showed that the unconstraint vibration treatment can lead to the residual strain of the fatigued copper film to be reduced and redistributed. The effect of the vibration parameters on the treatment effectiveness was analyzed by the different fatigue experiments and unconstraint vibration treatments, and the results showed that the FE simulation results are in agreement with the experimental observations.

Studies of the microbial metabolism of flavonoids extracted from the leaves of Diospyros kaki by intestinal bacteria

Sheng-hai Zhang,Ying-zi Wang,Fan-yun Meng,You-lin Li,Cai-xia Li,Fei-peng Duan,Qing Wang,Xiu-ting Zhang,Chun-ni Zhang 대한약학회 2015 Archives of Pharmacal Research Vol.38 No.5

Flavonoid glycosides are metabolized byintestinal bacteria, giving rise to a wide range of phenolicacids that may exert systemic effects in the body. Themicrobial metabolism of flavonoids extracted from theleaves of Diospyros kaki (FLDK) by intestinal bacteria wasinvestigated in vitro. High-performance liquid chromatography/linear trap quadrupole orbitrap mass spectrometrywas performed to analyze the metabolites of flavonoidsin vivo using Xcalibur2.1 software. The results showed thatthe levels of flavonoid glycosides and flavonoid aglyconesdecreased rapidly in the process of microbial metabolismby intestinal bacteria in vitro, and the metabolic rate maybe related to the concentration of intestinal bacteria in theculture solution. In vivo metabolites of FLDK weredetected in rat plasma and urine after oral administration ofFLDK. Eight flavonoids were identified in the urine, andthree were identified in the plasma; however, flavonoidaglycones were not found in the plasma.

중국 항공물류 산업의 문제점과 개선 방안에 관한 연구

장몽택(Zhang, Meng-Ze),장 연(Zhang, Yan),손해양(Sun, Hai-Yang),배기형(Bae, Ki-Hyung) 한국물류학회 2018 물류학회지 Vol.28 No.5

This study’s purpose is to propose improvement program about analyzing issues according to the aviation logistics industry of China which is in its early stages as the logistics market opening. For this purpose, this study used internet and statistical information of Chinese government, reports of Chinese government agency, relating papers and publications, document literature which are relating to the aviation logistics. The results of the analysis are as follows. Issues of Chinese aviation logistics industry are shown as uneven development on regions and lacking of infrastructure, low level of information and smartification and shortage experts on macroscopic level, also it is appeared on micro level as logistics system backwardness and shortage of comprehensive competitiveness and lacking of cooperation in enterprises of aviation logistics, small-scale logistics enterprises and operational disorder, severe service homogeneity because of insufficient innovation. The improvement program about these obstructive factors is suggested that improve policies and systems of aviation logistics, improve of infrastructure construction, enhance level of information and smartification, develope education and professionals, promote cooperation’s development through integration, mutually develope through federation, enlarge scales and increasing ability of management, and create differentiation and service through innovation. 본 연구는 발전 초기단계인 중국의 항공물류 산업이 물류시장 개방에 따른 문제점을 분석하고 이에 대한 개선방안을 제시하는데 목적이 있다. 이를 위하여 본 연구에서는 인터넷 및 중국정부 통계 자료, 중국 정부 기관 보고서 및 관련 논문과 간행물 등 항공물류와 관련 문헌자료를 활용하였다. 분석결과는 다음과 같다. 중국 항공물류 산업의 문제점은 거시적 측면에서 지역 간의 발전 불균형 및 인프라 부족, 정보화와 스마트화 수준 저하, 전문가 부족 등으로 나타났고, 미시적 측면에서 물류 체계와 종합 경쟁력 부진 및 협력 부재, 물류업체 소규모 및 업무 절차 혼잡, 혁신 부족으로 인한 서비스 동질화 심각 등으로 파악되었다. 이러한 문제 점들에 대한 개선 방안으로는 항공물류 정책 및 제도의 개선, 인프라 보완 및 강화, 정보화와 스마트화의 구축 및 증대, 교육 및전문 인재의 육성, 일체화를 통한 협력 발전, 연맹을 통한 상생 발전, 규모 학대 및 관리 능력 제고, 혁신을 통한 차별화 와 서비스의 창출 등이 요구된다.

Development and Characterization of a Novel Anti-idiotypic Monoclonal Antibody to Growth Hormone, Which Can Mimic Physiological Functions of Growth Hormone in Primary Porcine Hepatocytes

Hai-Nan Lan,Hai-Long Jiang,Wei Li,Tian-Cheng Wu,Pan Hong,Yu Meng Li,Hui Zhang,Huan-Zhong Cui,Xin Zheng 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.4

B-32 is one of a panel of monoclonal anti-idiotypic antibodies to growth hormone (GH) that we developed. To characterize and identify its potential role as a novel growth hormone receptor (GHR) agonist, we determined that B-32 behaved as a typical Ab2β based on a series of enzyme-linked immunosorbent assay assays. The results of fluorescence-activated cell sorting, indirect immunofluorescence and competitive receptor binding assays demonstrated that B-32 specifically binds to the GHR expressed on target cells. Next, we examined the resulting signal transduction pathways triggered by this antibody in primary porcine hepatocytes. We found that B-32 can activate the GHR and Janus kinase (2)/signal transducers and activators of transcription (JAK2/STAT5) signalling pathways. The phosphorylation kinetics of JAK2/STAT5 induced by either GH or B-32 were analysed in dose-response and time course experiments. In addition, B32 could also stimulate porcine hepatocytes to secrete insulin-like growth factors-1. Our work indicates that a monoclonal anti-idiotypic antibody to GH (B-32) can serve as a GHR agonist or GH mimic and has application potential in domestic animal (pig) production.

Tunicamycin enhances TRAIL-induced apoptosis by inhibition of cyclin D1 and the subsequent downregulation of survivin

Hai-Yan Zhang,Zhen-Xian Du,Bao-Qin Liu,Yan-Yan Gao,Xin Meng,Yifu Guan,Wei-Wei Deng,Hua-Qin Wang 생화학분자생물학회 2009 Experimental and molecular medicine Vol.41 No.5

TNF-related apoptosis-inducing ligand (TRAIL) has been proposed as a promising cancer therapy that preferentially induces apoptosis in cancer cells, but not most normal tissues. However, many cancers are resistant to TRAIL by mechanisms that are poorly understood. In this study, we showed that tunicamycin, a naturally occurring antibiotic, was a potent enhancer of TRAIL-induced apoptosis through downregulation of survivin. The tunicamycin-mediated sensitization to TRAIL was efficiently reduced by forced expression of survivin, suggesting that the sensitization was mediated at least in part through inhibition of survivin expression. Tunicamycin also repressed expression of cyclin D1, a cell cycle regulator commonly overexpressed in thyroid carcinoma. Furthermore, silencing cyclin D1 by RNA interference reduced survivin expression and sensitized thyroid cancer cells to TRAIL; in contrast, forced expression of cyclin D1 attenuated tunicamycin-potentiated TRAIL-induced apoptosis via over-riding downregulation of survivin. Collectively, our results demonstrated that tunicamycin promoted TRAIL-induced apoptosis, at least in part, by inhibiting the expression of cyclin D1 and subsequent survivin. Of note, tunicamycin did not sensitize the differentiated thyroid epithelial cells to TRAIL-induced apoptosis. Thus, combined treatment with tunicamycin and TRAIL may offer an attractive strategy for safely treating resistant thyroid cancers. TNF-related apoptosis-inducing ligand (TRAIL) has been proposed as a promising cancer therapy that preferentially induces apoptosis in cancer cells, but not most normal tissues. However, many cancers are resistant to TRAIL by mechanisms that are poorly understood. In this study, we showed that tunicamycin, a naturally occurring antibiotic, was a potent enhancer of TRAIL-induced apoptosis through downregulation of survivin. The tunicamycin-mediated sensitization to TRAIL was efficiently reduced by forced expression of survivin, suggesting that the sensitization was mediated at least in part through inhibition of survivin expression. Tunicamycin also repressed expression of cyclin D1, a cell cycle regulator commonly overexpressed in thyroid carcinoma. Furthermore, silencing cyclin D1 by RNA interference reduced survivin expression and sensitized thyroid cancer cells to TRAIL; in contrast, forced expression of cyclin D1 attenuated tunicamycin-potentiated TRAIL-induced apoptosis via over-riding downregulation of survivin. Collectively, our results demonstrated that tunicamycin promoted TRAIL-induced apoptosis, at least in part, by inhibiting the expression of cyclin D1 and subsequent survivin. Of note, tunicamycin did not sensitize the differentiated thyroid epithelial cells to TRAIL-induced apoptosis. Thus, combined treatment with tunicamycin and TRAIL may offer an attractive strategy for safely treating resistant thyroid cancers.

IL-33 promotes IL-10 production in macrophages: a role for IL-33 in macrophage foam cell formation

Hai-Feng Zhang,Mao-Xiong Wu,Yong-Qing Lin,Shuang-Lun Xie,Tu-Cheng Huang,Pin-Ming Liu,Ru-Qiong Nie,Qin-Qi Meng,Nian-Sang Luo,Yang-Xin Chen,Jing-Feng Wang 생화학분자생물학회 2017 Experimental and molecular medicine Vol.49 No.-

We evaluated the role of IL-10- in IL-33-mediated cholesterol reduction in macrophage-derived foam cells (MFCs) and the mechanism by which IL-33 upregulates IL-10. Serum IL-33 and IL-10 levels in coronary artery disease patients were measured. The effects of IL-33 on intra-MFC cholesterol level, IL-10, ABCA1 and CD36 expression, ERK 1/2, Sp1, STAT3 and STAT4 activation, and IL-10 promoter activity were determined. Core sequences were identified using bioinformatic analysis and sitespecific mutagenesis. The serum IL-33 levels positively correlated with those of IL-10. IL-33 decreased cellular cholesterol level and upregulated IL-10 and ABCA1 but had no effect on CD36 expression. siRNA-IL-10 partially abolished cellular cholesterol reduction and ABCA1 elevation by IL-33 but did not reverse the decreased CD36 levels. IL-33 increased IL-10 mRNA production but had little effect on its stability. IL-33 induced ERK 1/2 phosphorylation and increased the luciferase expression driven by the IL-10 promoter, with the highest extent within the − 2000 to − 1752 bp segment of the 5′-flank of the transcription start site; these effects were counteracted by U0126. IL-33 activated Sp1, STAT3 and STAT4, but only the STAT3 binding site was predicted in the above segment. Site-directed mutagenesis of the predicted STAT3-binding sites (CTGCTTCCTGGCAGCAGAA→CTGCCTGGCAGCAGAA) reduced luciferase activity, and a STAT3 inhibitor blocked the regulatory effects of IL-33 on IL-10 expression. Chromatin immunoprecipitation (CHIP) confirmed the STAT3-binding sequences within the − 1997 to − 1700 and − 1091 to − 811 bp locus regions. IL-33 increased IL-10 expression in MFCs via activating ERK 1/2 and STAT3, which subsequently promoted IL-10 transcription and thus contributed to the beneficial effects of IL-33 on MFCs.

Rapid Screening of Maize Inbred Lines Based on NIR-MIR Spectral Characteristics and Small-molecule Metabolites

Meng Ting Li,Ren Jie Yang,Hai Xue Liu,Yang Liu,Xiao Qian Zhang,Xiao Dong Xie 한국작물학회 2018 Journal of crop science and biotechnology Vol.21 No.4

Near-infrared (NIR), Mid-infrared (MIR) spectroscopy and Gas chromatography -mass spectrometry (GC-MS) combined with principal component analysis (PCA) were used to preliminarily select suitable maize parents that can be further employed in future breeding process. Especially, a new matrix was innovatively developed in terms of metabolic components, and used for PCA. Firstly, the quality maize seeds were selected based on the score plots from PCA of NIR, MIR, fusion of NIR and MIR, and GC-MS. Then, the potential biomarkers, including phenol, propionic acid, DL-malic acid, L-valine, which have great influence on the selection of quality maize seeds, were confirmed based on the loading plots from PCA of GC-MS and MIR spectral data. Finally, the quantitative analysis of partial biomarkers for selected parents was carried based on GC-MS method. The selected suitable maize parents were further confirmed by the difference of biomarkers contents. The results showed that NIR, MIR, and GC-MS combined with PCA are as rapid, convenient analysis methods, and can be thus employed for future maize breeding process.

Development and Characterization of a Novel Anti-idiotypic Monoclonal Antibody to Growth Hormone, Which Can Mimic Physiological Functions of Growth Hormone in Primary Porcine Hepatocytes

Lan, Hai-Nan,Jiang, Hai-Long,Li, Wei,Wu, Tian-Cheng,Hong, Pan,Li, Yu Meng,Zhang, Hui,Cui, Huan-Zhong,Zheng, Xin Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.4

B-32 is one of a panel of monoclonal anti-idiotypic antibodies to growth hormone (GH) that we developed. To characterize and identify its potential role as a novel growth hormone receptor (GHR) agonist, we determined that B-32 behaved as a typical $Ab2{\beta}$ based on a series of enzyme-linked immunosorbent assay assays. The results of fluorescence-activated cell sorting, indirect immunofluorescence and competitive receptor binding assays demonstrated that B-32 specifically binds to the GHR expressed on target cells. Next, we examined the resulting signal transduction pathways triggered by this antibody in primary porcine hepatocytes. We found that B-32 can activate the GHR and Janus kinase (2)/signal transducers and activators of transcription (JAK2/STAT5) signalling pathways. The phosphorylation kinetics of JAK2/STAT5 induced by either GH or B-32 were analysed in dose-response and time course experiments. In addition, B32 could also stimulate porcine hepatocytes to secrete insulin-like growth factors-1. Our work indicates that a monoclonal anti-idiotypic antibody to GH (B-32) can serve as a GHR agonist or GH mimic and has application potential in domestic animal (pig) production.

Expression of RECK and MMPs in Hepatoblastoma and Neuroblastoma and Comparative Analysis on the Tumor Metastasis

Xu, Meng,Wang, Hai-Feng,Zhang, Huan-Zhi Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.9

Objective: To explore the expression of RECK and relevant matrix metalloproteinases (MMPs) in hepatoblastoma (HB) and neuroblastoma (NB) and their clinical significance in the tumor metastasis. Materials and Methods: Forty-five wax-stone samples of HB and 43 wax-stone samples of NB removed by surgical resection and confirmed by pathology in Linyi Yishui Central Hospital were selected. According to presence and absence of metastasis, both NB and HB samples were divided into metastatic group and non-metastatic group, namely NB metastatic group (n=28), NB non-metastatic group (n=15), HB metastatic group (n=15) and HB non-metastatic group (n=30). The expression of RECK, membrane type-1 matrix metalloproteinase (MT1-MMP) in HB tissue and RECK, MMP-14 in NB tissue was detected using immunohistochemical method, and the correlation between RECK and MT1-MMP, MMP-14 was analyzed. Results: The metastatic rate of NB was dramatically higher than that of HB, with statistical significance (P=0.003). The positive rate of RECK expression in NB group (30.2%) was slightly lower than in HB group (40.0%), but no significant difference was presented (P=0.338). The positive rate of MMPs expression in NB metastatic group was evidently higher than in HB metastatic group (P=0.024). The results of Spearman correlation analysis revealed that the expression of RECK in HB and NB tissues had a significantly-negative correlation with MT1-MMP and MMP-14, respectively (r=-0.499, P=0.012; r=-0.636, P=0.000). Conclusions: In HB and NB tissues, RECK is expressed lowly, while relevant MMPs highly, and RECK inhibits the tumor invasion and metastasis through negative regulation of relevant MMPs.