A New Microtiter Plate-based Screening Method for Microorganisms Producing Alpha-amylase Inhibitors

Zhi-Hua Feng,Yuan-Shan Wang,Yu-Guo Zheng 한국생물공학회 2011 Biotechnology and Bioprocess Engineering Vol.16 No.5

Alpha-amylase inhibitors are widely used by the pharmaceutical and agricultural industries, such as the treatment of diabetes and obesity and insect controller. Here, we developed a colorimetric method to screen for α-amylase inhibitor producing strains or mutants with higher α-amylase inhibitor productivity. This method relies on absorbance changes at 402 nm that are due to the inhibition of α-amylase catalyzed hydrolysis of 2-Chloro-4-nitrophenyl-4-O-β-D-galactopyranosyl-maltoside by α-amylase inhibitors. The assay can be performed on a microtiter plate, making it simple and convenient. Using this method,α-amylase inhibitor producing strains and mutants with higher α-amylase inhibitor productivity can be rapidly screened. One strain, ZJB-08196, with the highest α-amylase inhibition was isolated and identified as Actinoplanes utahensis, and one mutant with higher acarbose production was obtained by screening 3,000 variants using this method.

A damage localization method based on the singular value decomposition (SVD) for plates

Zhi-Bo Yang,Jin-Tao Yu,Shao-Hua Tian,Xue-Feng Chen,Guan-Ji Xu 국제구조공학회 2018 Smart Structures and Systems, An International Jou Vol.22 No.5

Boundary effect and the noise robustness are the two crucial aspects which affect the effectiveness of the damage localization based on the mode shape measurements. To overcome the boundary effect problem and enhance the noise robustness in damage detection, a simple damage localization method is proposed based on the Singular Value Decomposition (SVD) for the mode shape of composite plates. In the proposed method, the boundary effect problem is addressed by the decomposition and reconstruction of mode shape, and the noise robustness in enhanced by the noise filtering during the decomposition and reconstruction process. Numerical validations are performed on plate-like structures for various damage and boundary scenarios. Validations show that the proposed method is accurate and effective in the damage detection for the two-dimensional structures.

History, Law, and Culture in East Asian Politics : Contested Border: A Historical Investigation into the Sino-Korean Border Issue, 1950-1964

( Zhi Hua Shen ),( Ya Feng Xia ) 경남대학교 극동문제연구소 2013 ASIAN PERSPECTIVE Vol.37 No.1

The contested Sino-Korean border issue has received very little study. Making use of presently available sources in the several different archives in China and Taiwan, as well as documents made public in South Korea, we examine in this article the historical background of the Sino-Korean border issue and border relations from 1950 to 1964. North Korea was dissatisfied with the Jiandao Treaty of 1909, but was uneasy about raising that dissatisfaction with the Chinese in the 1950s. When China was caught in a number of woeful domestic and international predicaments in 1962, Pyongyang seized the opportunity and proposed to Beijing that the border issue be settled. It took the two sides only six months to negotiate and sign a new boundary treaty. As a result, North Korea emerged with a larger share of Tianchi and other disputed areas.

Bayesian forecasting approach for structure response prediction and load effect separation of a revolving auditorium

Zhi Ma,Chung-Bang Yun,Yan-Bin Shen,Feng Yu,Hua-Ping Wan,Yao-Zhi Luo 국제구조공학회 2019 Smart Structures and Systems, An International Jou Vol.24 No.4

A Bayesian dynamic linear model (BDLM) is presented for a data-driven analysis for response prediction and load effect separation of a revolving auditorium structure, where the main loads are self-weight and dead loads, temperature load, and audience load. Analyses are carried out based on the long-term monitoring data for static strains on several key members of the structure. Three improvements are introduced to the ordinary regression BDLM, which are a classificatory regression term to address the temporary audience load effect, improved inference for the variance of observation noise to be updated continuously, and component discount factors for effective load effect separation. The effects of those improvements are evaluated regarding the root mean square errors, standard deviations, and 95% confidence intervals of the predictions. Bayes factors are used for evaluating the probability distributions of the predictions, which are essential to structural condition assessments, such as outlier identification and reliability analysis. The performance of the present BDLM has been successfully verified based on the simulated data and the real data obtained from the structural health monitoring system installed on the revolving structure.

Structural Maintenance of Chromosomes 4 is a Predictor of Survival and a Novel Therapeutic Target in Colorectal Cancer

Feng, Xiao-Dong,Song, Qi,Li, Chuan-Wei,Chen, Jian,Tang, Hua-Mei,Peng, Zhi-Hai,Wang, Xue-Chun Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.21

Background: Structural maintenance of chromosomes 4 (SMC-4) is a chromosomal ATPase which plays an important role in regulate chromosome assembly and segregation. However, the role of SMC-4 in the incidence of malignancies, especially colorectal cancer is still poorly understood. Materials and Methods: We here used quantitative PCR and Western blot analysis to examine SMC-4 mRNA and protein levels in primary colorectal cancer and paired normal colonic mucosa. SMC-4 clinicopathological significance was assessed by immunohistochemical staining in a tissue microarray (TMA) in which 118 cases of primary colorectal cancer were paired with noncancerous tissue. The biological function of SMC-4 knockdown was measured by CCK8 and plate colony formation assays. Fluorescence detection has been used to detect cell cycling and apoptosis. Results: SMC-4 expression was significantly higher in colorectal cancer and associated with T stage, N stage, AJCC stage and differentiation. Knockdown of SMC-4 expression significantly suppressed the proliferation of cancer cells and degraded its malignant degree. Conclusions: Our clinical and experimental data suggest that SMC-4 may contribute to the progression of colorectal carcinogenesis. Our study provides a new therapeutic target for colorectal cancer treatment.

Coordinated Control Strategies with and without Circulating Current in Unified Power Quality

Feng, Xing-tian,Zhang, Zhi-hua The Korean Institute of Power Electronics 2015 JOURNAL OF POWER ELECTRONICS Vol.15 No.5

Under traditional unified power quality conditioner (UPQC) control, a UPQC series converter (SC) is mainly used to handle grid-side power quality problems while its parallel converter (PC) is mainly used to handle load-side power quality problems. The SC and PC are relatively independent. The SC is usually in standby mode and it only runs when the grid voltage abruptly changes. In this paper, novel UPQC coordinated control strategies are proposed which use the SC to share the reactive power compensation function of the PC especially without grid-side power quality problems. However, in some cases, there will be a circulating current between the SC and the PC, which will probably influence the compensation fashion, the compensation capacity, or the normal work of the UPQC. Through an active power circulation analysis, strategies with and without a circulating current are presented which fuses the reactive power allocation strategy of the SC and the PC, the composite control strategy of the SC and the compensation strategy of the DC storage unit. Both of the strategies effectively solve the SC long term idle problem, limit the influence of the circulating current, optimize all of the UPQC units and reduce the production cost. An analysis, along with simulation andexperimental results, is presented to verify the feasibility and effectiveness of the proposed control strategies.

Efficacy of Pap Test in Combination with ThinPrep Cytological Test in Screening for Cervical Cancer

Chen, Hua,Shu, Hui-Min,Chang, Zhou-Lin,Wang, Zhi-Feng,Yao, Hai-Hong,Zhu, Hong-Mei,Lu, Tian-Mei,Ma, Qiang-Yan,Yang, Bin-Lie Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.4

Background: Our aim was to investigate the efficacy of the Pap test in combination with the ThinPrep cytological test (TCT) in screening for cervical cancer in China. Design: From March 2006 to October 2008, 988 women with the mean age $46.4{\pm}10.5$ years (range, 23-80 years) were recruited to receive cervical cancer screening. Pap test results ${\geq}$ grade III and TCT findings ${\geq}$ ASCUS/AGUS were considered abnormal. Subjects with a Pap test result ${\geq}$ grade IIb received TCT. Colposcopy and biopsies were performed in all participants, and final diagnosis was based on pathological findings. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and Youden index for predicting CIN I or above were determined. Results: The sensitivity, specificity, PPV, NPV and Youden index of the Pap test were 43.1%, 97.2%, 70.0%, 91.9%, and 40.3%, respectively. The same values for TCT in predicting CIN were 80.0%, 63.2%, 16.0%, 97.3%, and 43.2%, respectively. The two tests in combination gave values for predicting CIN of 64.8%, 87.6%, 43.6%, 94.4%, and 53.5%, respectively. Combined testing exhibited the highest Youden index (53.4%). Conclusion: The Pap test with a reduced threshold in combination with the TCT has high sensitivity and high specificity in screening for cervical cancer.

Indole-3-propionic acid inhibits gut dysbiosis and endotoxin leakage to attenuate steatohepatitis in rats

Ze-Hua Zhao,Feng-Zhi Xin,Yaqian Xue,Zhimin Hu,Yamei Han,Fengguang Ma,Da Zhou,Xiao-Lin Liu,Aoyuan Cui,Zhengshuai Liu,Yuxiao Liu,Jing Gao,Qin Pan,Yu Li,Jian-Gao Fan 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

Microbial metabolites have emerged as critical components that mediate the metabolic effects of the gut microbiota. Here, we show that indole-3-propionic acid (IPA), a tryptophan metabolite produced by gut bacteria, is a potent anti-non-alcoholic steatohepatitis (NASH) microbial metabolite. Here, we demonstrate that administration of IPA modulates the microbiota composition in the gut and inhibits microbial dysbiosis in rats fed a high-fat diet. IPA induces the expression of tight junction proteins, such as ZO-1 and Occludin, and maintains intestinal epithelium homeostasis, leading to a reduction in plasma endotoxin levels. Interestingly, IPA inhibits NF-κB signaling and reduces the levels of proinflammatory cytokines, such as TNFα, IL-1β, and IL-6, in response to endotoxin in macrophages to repress hepatic inflammation and liver injury. Moreover, IPA is sufficient to inhibit the expression of fibrogenic and collagen genes and attenuate diet-induced NASH phenotypes. The beneficial effects of IPA on the liver are likely mediated through inhibiting the production of endotoxin in the gut. These findings suggest a protective role of IPA in the control of metabolism and uncover the gut microbiome and liver cross-talk in regulating the intestinal microenvironment and liver pathology via a novel dietary nutrient metabolite. IPA may provide a new therapeutic strategy for treating NASH.

A damage localization method based on the singular value decomposition (SVD) for plates

Yang, Zhi-Bo,Yu, Jin-Tao,Tian, Shao-Hua,Chen, Xue-Feng,Xu, Guan-Ji Techno-Press 2018 Smart Structures and Systems, An International Jou Vol.22 No.5

Boundary effect and the noise robustness are the two crucial aspects which affect the effectiveness of the damage localization based on the mode shape measurements. To overcome the boundary effect problem and enhance the noise robustness in damage detection, a simple damage localization method is proposed based on the Singular Value Decomposition (SVD) for the mode shape of composite plates. In the proposed method, the boundary effect problem is addressed by the decomposition and reconstruction of mode shape, and the noise robustness in enhanced by the noise filtering during the decomposition and reconstruction process. Numerical validations are performed on plate-like structures for various damage and boundary scenarios. Validations show that the proposed method is accurate and effective in the damage detection for the two-dimensional structures.

High Performance Current Sensing Circuit for Current-Mode DC-DC Buck Converter

Hai-Feng Jin,Hua-Lan Piao,Zhi-Yuan Cui,김남수 한국전기전자재료학회 2010 Transactions on Electrical and Electronic Material Vol.11 No.1

A simulation study of a current-mode direct current (DC)-DC buck converter is presented in this paper. The converter, with a fully integrated power module, is implemented by using sense method metal-oxide-semiconductor field-effect transistor (MOSFET) and bipolar complementary metal–oxide–semiconductor (BiCMOS) technology. When the MOSFET is used in a current sensor, the sensed inductor current with an internal ramp signal can be used for feedback control. In addition, the BiCMOS technology is applied in the converter for an accurate current sensing and a low power consumption. The DC-DC converter is designed using the standard 0.35 μm CMOS process. An off-chip LC filter is designed with an inductance of 1 mH and a capacitance of 12.5 nF. The simulation results show that the error between the sensing signal and the inductor current can be controlled to be within 3%. The characteristics of the error amplification and output ripple are much improved, as compared to converters using conventional CMOS circuits.