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East Asian International Relations and Korean Peninsula (东亚国际形势与朝鲜半岛)

  • Zheng, Jiyong
    • Analyses & Alternatives
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    • v.1 no.1
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    • pp.31-43
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    • 2017
  • The situation in Korean peninsula, globally and regionally, which followed the global huge uncertainty, changed a lot. Because of the political crisis, ROK falls into a chaos. And DPRK goes into a policy changing period by the internal issues, international sanctions and assassination accident in Malaysia, which is confirmed to be DPRK's Supreme leader, Kim Jong Un's half brother. Under this changing circumstances, the perspectives of regarding China and the Korean peninsula, must be undated accordingly. Only by understanding the Sino-US relations, the DPRK nuclear issue and the regional dilemmas can we formulate reasonable policies to contribute to the peace and stability of the Korean Peninsula.

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Performance Analysis and Evaluation of Deployment in Small Cell Networks

  • Zheng, Kan;Li, Yue;Zhang, Yingkai;Jiang, Zheng;Long, Hang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.3
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    • pp.886-900
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    • 2015
  • Small cells are deployed in Heterogeneous Networks (HetNet) to improve overall performance. These access points can provide high-rate mobile services at hotspots to users. In a Small Cell Network (SCN), the good deployment of small cells can guarantee the performance of users on the basis of average and cell edge spectrum efficiency. In this paper, the performance of small cell deployment is analyzed by using system-level simulations. The positions of small cells can be adjusted according to the deployment radius and angle. Moreover, different Inter-Cell Interference Coordination (ICIC) techniques are also studied, which can be implemented either in time domain or in frequency domain. The network performances are evaluated under different ICIC techniques when the locations of Small evolved Nodes (SeNBs) vary. Simulation results show that the average throughput and cell edge throughput can be greatly improved when small cells are properly deployed with the certain deployment radius and angle. Meanwhile, how to optimally configure the parameters to achieve the potential of the deployment is discussed when applying different ICIC techniques.

Optimization of Parameters for LCL Filter of Least Square Method Based Three-phase PWM Converter

  • Zheng, Hong;Liang, Zheng-feng;Li, Meng-shu;Li, Kai
    • Journal of Electrical Engineering and Technology
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    • v.10 no.4
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    • pp.1626-1634
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    • 2015
  • LCL filters are widely used in three-phase PWM converter for its advantages of small volume, low cost and inhibition of high frequency current harmonic. However, it is difficult to optimize its design because its parameters are mutually influenced while the value of each parameter for LCL filter has impacts on the converter's cost and size. In this paper, the target of optimization is to minimize the parameter values of LCL filter, and an optimization method for parameters of LCL filter of three-phase PWM converter based on least square method is proposed. With this method, a quantitative calculation of the harmonic component of the converter’s side phase voltage is performed first, and then the quantitative relationship between phase voltage harmonics and grid phase current harmonics is analyzed. After that, the attenuation requirement of each harmonic is obtained by taking into account the requirements for each harmonic component of grid current. Then according to the optimization objective, the objective function with minimum harmonic attenuation deviation is established, and least squares method is adopted for three-dimensional global searching of parameters for LCL filter. Thus, the designed harmonic attenuation curve approximates the minimum attenuation requirements, and the optimized LCL filter parameters are obtained. Finally, the effectiveness of the method is verified by the experiments.

Vesicular Stomatitis Virus G Glycoprotein and ATRA Enhanced Bystander Killing of Chemoresistant Leukemic Cells by Herpes Simplex Virus Thymidine Kinase/Ganciclovir

  • Hu, Chenxi;Chen, Zheng;Zhao, Wenjun;Wei, Lirong;Zheng, Yanwen;He, Chao;Zeng, Yan;Yin, Bin
    • Biomolecules & Therapeutics
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    • v.22 no.2
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    • pp.114-121
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    • 2014
  • Refractoriness of acute myeloid leukemia (AML) cells to chemotherapeutics represents a major clinical barrier. Suicide gene therapy for cancer has been attractive but with limited clinical efficacy. In this study, we investigated the potential application of herpes simplex virus thymidine kinase/ganciclovir (HSV-TK/GCV) based system to inhibit chemoresistant AML cells. We first generated Ara-C resistant K562 cells and doxorubicin-resistant THP-1 cells. We found that the HSV-TK/GCV anticancer system suppressed drug resistant leukemic cells in culture. Chemoresistant AML cell lines displayed similar sensitivity to HSV-TK/GCV. Moreover, HSV-TK/GCV killing of leukemic cells was augmented to a mild but significant extent by all-trans retinoic acid (ATRA) with concomitant upregulation of Connexin 43, a major component of gap junctions. Interestingly, HSV-TK/GCV killing was enhanced by expression of vesicular stomatitis virus G glycoprotein (VSV-G), a fusogenic membrane protein, which also increased leukemic cell fusion. Co-culture resistant cells expressing HSV-TK and cells stably transduced with VSV-G showed that expression of VSV-G could promote the bystander killing effect of HSV-TK/GCV. Furthermore, combination of HSV-TK/GCV with VSV-G plus ATRA produced more pronounced antileukemia effect. These results suggest that the HSV-TK/GCV system in combination with fusogenic membrane proteins and/or ATRA could provide a strategy to mitigate the chemoresistance of AML.

Monitoring the Ecology of Bacillus During Daqu Incubation, a Fermentation Starter, Using Culture-Dependent and Culture-Independent Methods

  • Yan, Zheng;Zheng, Xiao-Wei;Han, Bei-Zhong;Han, Jian-Shu;Nout, M.J. Robert;Chen, Jing-Yu
    • Journal of Microbiology and Biotechnology
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    • v.23 no.5
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    • pp.614-622
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    • 2013
  • Daqu, a traditional fermentation starter, has been used to produce attractively flavored foods such as vinegar and Chinese liquor for thousands of years. Although Bacillus spp. are one of the dominant microorganisms in Daqu, more precise information is needed to reveal why and how Bacillus became dominant in Daqu, and next, to assess the impact of Bacillus sp. on Daqu and its derived products. We combined culture-dependent and culture-independent methods to study the ecology of Bacillus during Daqu incubation. Throughout the incubation, 67 presumptive Bacillus spp. isolates were obtained, 52 of which were confirmed by 16S rDNA sequencing. The identified organisms belonged to 8 Bacillus species: B. licheniformis, B. subtilis, B. amyloliquefaciens, B. cereus, B. circulans, B. megaterium, B. pumilus, and B. anthracis. A primer set specific for Bacillus and related genera was used in a selective PCR study, followed by a nested DGGE PCR targeting the V9 region of the 16S rDNA. Species identified from the PCR-DGGE fingerprints were related to B. licheniformis, B. subtilis, B. amyloliquefaciens, B. pumilus, B. benzoevorans, and B. foraminis. The predominant species was found to be B. licheniformis. Certain B. licheniformis strains exhibited potent antimicrobial activities. The greatest species diversity occurred at the Liangmei stage of Daqu incubation. To date, we lack sufficient knowledge of Bacillus distribution in Daqu. Elucidating the ecology of Bacillus during Daqu incubation would enable the impact of Bacillus on Daqu to be accessed, and the quality and stabilization of Daqu-derived products to be optimized.

Time Trends of Ovarian Cancer Incidence in China

  • Wang, Bing;Liu, Shu-Zheng;Zheng, Rong-Shou;Zhang, Fang;Chen, Wan-Qing;Sun, Xi-Bin
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.1
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    • pp.191-193
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    • 2014
  • The aim of this study was to examine the trend of ovary cancer incidence from 1999 to 2010 in China and predict the burden up to 2020. Crude incidence, age specific incidence and age-adjusted incidence rates were calculated. Joinpoint regression was performed to obtain estimated annual percentages and Bayesian age-period-cohort modeling was used to predict the incidence rate until the year 2020. In China, the crude rate of ovary cancer was 7.91/100,000 and the age-adjusted rate was 5.35/100,000 overall during period 1999-2010. The rates in urban regions were higher than in rural regions. A significant rising trend during 1999-2006 was followed by a drop during 2006-2010 in age-adjusted rates for urban females. In contrast, constant rise was observed in rural women. The decrease in ovary cancer of urban areas tended to be restricted to women aged 50 years and younger. In contrast, increases of ovary cancer in rural areas appeared in virtually all age groups. Although the age-adjusted incidence rate for ovary cancer was predicted to be reduced after year 2011, the crude rate was likely to be relative stable up to 2020. The burden of ovary cancer in China will continue to be relative stable due to the aging population.

No Association Between Tea Consumption and Risk of Renal Cell Carcinoma: A Meta-analysis of Epidemiological Studies

  • Hu, Zheng-Hui;Lin, Yi-Wei;Xu, Xin;Chen, Hong;Mao, Ye-Qing;Wu, Jian;Xu, Xiang-Lai;Zhu, Yi;Li, Shi-Qi;Zheng, Xiang-Yi;Xie, Li-Ping
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.3
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    • pp.1691-1695
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    • 2013
  • Objective: To evaluate the association between tea consumption and the risk of renal cell carcinoma. Methods: We searched PubMed, Web of Science and Scopus between 1970 and November 2012. Two evaluators independently reviewed and selected articles based on predetermined selection criteria. Results: Twelve epidemiological studies (ten case-control studies and two cohort studies) were included in the final analysis. In a meta-analysis of all included studies, when compared with the lowest level of tea consumption, the overall relative risk (RR) of renal cell carcinoma for the highest level of tea consumption was 1.03 (95% confidence interval [CI] 0.89-1.21). In subgroup meta-analyses by study design, there was no significant association between tea consumption and renal cell carcinoma risk in ten case-control studies using adjusted data (RR=1.08, 95% CI 0.84-1.40). Furthermore, there was no significant association in two cohort studies using adjusted data (RR=0.95, 95% CI 0.81-1.12). Conclusion: Our findings do not support the conclusion that tea consumption is related to decreased risk of renal cell carcinoma. Further prospective cohort studies are required.

Characteristics of SrCo1-xFexO3-δ Perovskite Powders with Improved O2/CO2 Production Performance for Oxyfuel Combustion

  • Shen, Qiuwan;Zheng, Ying;Luo, Cong;Zheng, Chuguang
    • Bulletin of the Korean Chemical Society
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    • v.35 no.6
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    • pp.1613-1618
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    • 2014
  • Perovskite-type oxides are promising oxygen carriers in producing oxygen-enriched $CO_2$ gas stream for oxyfuel combustion. In this study, a new series of $SrCo_{1-x}Fe_xO_{3-{\delta}}$ (x = 0.2, 0.4, 0.6, 0.8) was prepared and used to produce $O_2/CO_2$ mixture gas. The phase, crystal structure, and morphological properties of $SrCo_{1-x}Fe_xO_{3-{\delta}}$ were investigated through X-ray diffraction, specific surface area measurements, and environmental scanning electron microscopy. The oxygen desorption performance of $SrCo_{1-x}Fe_xO_{3-{\delta}}$ was studied in a fixed-bed reactor system. Results showed that the different x values of $SrCo_{1-x}Fe_xO_{3-{\delta}}$ have no obvious effects on crystalline structure. However, the oxygen desorption performance of $SrCo_{1-x}Fe_xO_{3-{\delta}}$ is improved by Co doping. Moreover, $SrCo_{0.8}Fe_{0.2}O_{3-{\delta}}$ synthesized via a new EDTA method has a larger BET surface area ($40.396m^2/g$), smaller particle size (48.3 nm), and better oxygen production performance compared with that synthesized through a liquid citrate method.

Aberrant Expression of HOXA5 and HOXA9 in AML

  • Zhao, Peng;Tan, Li;Ruan, Jian;Wei, Xiao-Ping;Zheng, Yi;Zheng, Li-Xia;Jiang, Wei-Qin;Fang, Wei-Jia
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.9
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    • pp.3941-3944
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    • 2015
  • Background: Aberrant expression of HOX gene expression has been observed in cancer. The purpose of this study was to investigate the alteration of HOXA5 and HOXA9 expression and their clinical significance in acute meloid leukemia (AML). Materials and Methods: The expression of HOXA5 and HOXA9 genes of bone marrow samples from 75 newly diagnosed AML patients and 22 healthy controls for comparison were examined by Real-time quantitative PCR (RQ-PCR) assay. Statistical analysis was conducted to evaluate HOXA5 and HOXA9 expression as possible biomarkers for AML. Results: The results showed that the complete remission rate (52.6%) of the patients who highly expressed HOXA5 and HOXA9 was significantly lower than that (88.9%) in patients who lowly express the genes (P=0.015). Spearmann correlation coefficients indicated that the expression levels for HOXA5 and HOXA9 genes were highly interrelated (r=0.657, P<0.001). Meanwhile, we detected significant correlations between HOXA9 expression and age in this limited set of patients (P=0.009). Conclusions: The results suggest a prognostic impact of increased expression of HOXA5 and HOXA9 in AML patients.

Biomarkers Screening Between Preoperative and Postoperative Patients in Pancreatic Cancer

  • Li, Pei;Yang, Juan;Ma, Qing-Yong;Wu, Zheng;Huang, Chen;Li, Xu-Qi;Wang, Zheng
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.7
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    • pp.4161-4165
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    • 2013
  • Objective: To investigate discriminating protein patterns and potential biomarkers in serum samples between pre/postoperative pancreatic cancer patients and healthy controls. Methods: 23 serum samples from PC patients (12 preoperative and 11 postoperative) and 76 from healthy controls were analyzed using matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS) technique combined with magnetic beads-based weak cation-exchange chromatography (MB-WCX). ClinProTools software selected several markers that made a distinction between pancreatic cancer patients and healthy controls. Results: 49 m/z distinctive peaks were found among the three groups, of which 33 significant peaks with a P < 0.001 were detected. Two proteins could distinguish the preoperative pancreatic cancer patients from the healthy controls. About 15 proteins may be potential biomarkers in assessment of pancreatic cancer resection. Conclusion: MB-MALDI-TOF-MS method could generate serum peptidome profiles of pancreatic cancer and provide a new approach to identify potential biomarkers for diagnosis and prognosis of this malignancy.