Alisol A Inhibited the Proliferation, Migration, and Invasion of Nasopharyngeal Carcinoma Cells by Inhibiting the Hippo Signaling Pathway

Xianghong Chen,Huiqing Liu 연세대학교의과대학 2021 Yonsei medical journal Vol.62 No.10

Purpose: Alisol A is a bioactive triterpenoid isolated from the Rhizoma Alismatis. Previous studies have shown that alisol A has anticancer potential. In this study, we explored the effect of alisol A on the growth of nasopharyngeal carcinoma (NPC) cells. Materials and Methods: MTT assay, colony formation assay, flow cytometry, transwell assay, wound healing assay, and western blotting were used to assess cell viability, proliferation, cell cycle, migration, invasion, and protein expression, respectively, in vitro. AutoDock Vina and Discovery Studio software were used for molecular docking. Results: Alisol A inhibited the viability, proliferation, migration, and invasion of NPC cells. The molecular docking simulation assay confirmed that alisol A bound to YAP protein. In addition, alisol A promoted the phosphorylation of YAP and suppressed the expression of YAP in NPC cells. Conclusion: Alisol A inhibited the proliferation, migration, and invasion of NPC cells by inhibiting the Hippo signaling pathway. Alisol A may be a candidate drug for NPC.

Highly extendable multi‑channel LED driver with leakage energy recycling

Xianghong Kong,Junfeng Liu,Jun Zeng 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.7

This paper presents a single-stage single-switch multi-channel LED driver with high extendibility. The PFC module adopts a buck–boost circuit, which can achieve a high-power factor when it works in the discontinuous current mode (DCM). At the same time, the leakage inductor energy can be recycled by adding a capacitor at the primary side to reduce the voltage spike and ringing of the switch. The DC–DC module adopts a forward converter that plays the role of electrical isolation. Using capacitor charge balance, the converter can achieve output current balancing of all the channels. This converter can extend the number of output channels while using fewer capacitors than traditional LED drivers based on capacitor charge balance. In addition, the PFC module is integrated with the DC–DC module while sharing a common switch, which makes the control simple. This paper provides the concrete structure, working principle, and circuit characteristic analysis of the proposed topology. Finally, a 100 W prototype was built to verify its feasibility.

Cassava starch graft copolymer as an eco-friendly corrosion inhibitor for steel in H2SO4 solution

Xianghong Li,Shuduan Deng 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.11

Cassava starch graft copolymer (CSGC) was prepared by grafting acryl amide (AA) onto cassava starch (CS). The inhibition effect of CSGC on the corrosion of cold rolled steel (CRS) in 1.0M H2SO4 solution was first studied by weight loss, potentiodynamic polarization curves, electrochemical impedance spectroscopy (EIS) and scanning electron microscope (SEM) methods. The results show that CSGC is a good inhibitor, and inhibition efficiency of CSGC is higher than that of CS or AA. The adsorption of CSGC on steel surface obeys Langmuir adsorption isotherm. CSGC is a mixed-type inhibitor at 20 oC, while mainly a cathodic inhibitor at 50 oC.

Sensitive Electrochemiluminescence Immunosensor for Determination of Tumor Biomarker PSA Based on Multifunctionalized Pt/Ag@BSA Core–Shell Nanoparticles

Xianghong Xu 대한화학회 2016 Bulletin of the Korean Chemical Society Vol.37 No.4

A multifunctionalized bovine serum albumin encapsulated platinum and silver alloys core–shell nanoparticles (Pt/Ag@BSA NPs)-based electrochemiluminescence (ECL) immunosensor for ultrasensitive determination of tumor marker prostate-specific antigen (PSA) has been designed. In this work, Pt/Ag@BSA core–shell nanoparticles with large surface area, favorable electrical conductivity, and biocompatibility were employed as ideal multifunctional carriers to effectively immobilize numerous luminol molecules and PSA capture antibodies (Anti-PSA) acted as signal probe and molecule recognition probe, respectively. In addition, AuNPs were electrodeposited onto the indium tin oxide (ITO) to construct an outstanding base for this immunosensor, which could promote the electron transfer and load a large amount of multifunctionalized Pt/Ag@BSA nanoparticles. The constructed immunosensor could specifically capture PSA, which hindered the electron transfer of the ECL reaction between luminol and H2O2 because of the barrier of the attached immunoprotein layer and thereby resulted in the decrease of ECL intensity. Under the optimal conditions, ECL intensity of the immunosensor decreased linearly with the logarithm of PSA concentration ranging from 0.001 to 200 ng/mL with a low detection limit of 0.0003 ng/mL (S/N = 3). The proposed immunosensor exhibited high performances in sensitivity, reproducibility, stability, and specificity. Furthermore, the developed immunoassay has been applied to the detection of PSA in real serum samples with satisfactory results.

Multi-hop Range-Free Localization Algorithm For Wireless Sensor Network Using Principal Component Regression

Xianghong Tian,Wei Zhao,Xiaoyong Yan 보안공학연구지원센터 2015 International Journal of Grid and Distributed Comp Vol.8 No.1

In this paper, a novel approach to multi-hop range-free localization algorithm in wireless sensor network is proposed using principal component regression. The localization problem in the wireless sensor network is formulated as a multiple regression problem, which is resolved by principal component regression. The proposed methods are simple and efficient that no additional hardware is required for the measurements, and only hop-counts information and location information of the beacons are used for the localization. The proposed method consists of two phases: the offline training phase and the online localization phase. In offline training phase, the real distances and the hop-counts among sensor nodes are collected to build localization model. In online localization phase, each unknown sensor node finds its own location using the localization model. The experimental results show that compared with previous localization methods, the proposed method exhibits excellent and robust performances not only in the isotropic sensor networks but also in the anisotropic sensor networks.

Adsorption Behavior of Environmental Hormone Bisphenol A onto Mesoporous Silicon Dioxide

Xianghong Fan,Bing Tu,Hongmei Ma,Xuefen Wang 대한화학회 2011 Bulletin of the Korean Chemical Society Vol.32 No.8

Mesoporous silicon dioxide (meso-SiO)2) was prepared using cetyltrimethylammonium bromide as the structure-directing reagent and tetraethyl orthosicate as the silicon source. The influence of pH value on the adsorption behavior of bisphenol A (BPA) was investigated. The adsorption capacity of BPA onto meso-SiO_2increases slightly with pH value from 2 to 6, and then gradually decreases as further improving pH value. The effect of temperature was also studied, and the adsorption capacity of BPA gradually declines with increasing temperature. The adsorption kinetics and thermodynamics of BPA were examined. It is found that the adsorption of BPA onto meso-SiO_2 is in good agreement with Langmuir adsorption model. The rate constant of adsorption is 5.17 × 10^−3 g mg−1 min−1, and the maximum adsorption capacity is as high as 353.4 mg g^−1 at 20 ^oC.

Research on Clustering Algorithm Based on Grid Density on Uncertain Data Stream

Tang Xianghong,Yang Quanwei,Zheng Yang 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.9

To solve the clustering algorithm based on grid density on uncertain data stream in adjustment cycle for clustering omissions, the paper proposed an algorithm, named GCUDS, to cluster uncertain data steam using grid structure. The concept of the data trend degree was defined to describe the grade of a data point belonging to some grid unit and the defect of information loss around grid units was removed in the GCUDS algorithm. The GCUDS algorithm obtained better results of clustering and higher time efficiency than other algorithms over uncertain data stream, through improving the traditional online clustering framework and maintaining three buffers of micro-cluster. Experimental results showed that the GCUDS algorithm could effectively cluster in different shape database and outperform existing methods in clustering quality and efficiency.

Adsorption Behavior of Environmental Hormone Bisphenol A onto Mesoporous Silicon Dioxide

Fan, Xianghong,Tu, Bing,Ma, Hongmei,Wang, Xuefen Korean Chemical Society 2011 Bulletin of the Korean Chemical Society Vol.32 No.8

Mesoporous silicon dioxide (meso-$SiO_2$) was prepared using cetyltrimethylammonium bromide as the structure-directing reagent and tetraethyl orthosicate as the silicon source. The influence of pH value on the adsorption behavior of bisphenol A (BPA) was investigated. The adsorption capacity of BPA onto meso-$SiO_2$ increases slightly with pH value from 2 to 6, and then gradually decreases as further improving pH value. The effect of temperature was also studied, and the adsorption capacity of BPA gradually declines with increasing temperature. The adsorption kinetics and thermodynamics of BPA were examined. It is found that the adsorption of BPA onto meso-$SiO_2$ is in good agreement with Langmuir adsorption model. The rate constant of adsorption is $5.17{\times}10^{-3}g\;mg^{-1}\;min^{-1}$, and the maximum adsorption capacity is as high as 353.4 $mg\;g^{-1}$ at 20 $^{\circ}C$.

Performance Evaluation and Modeling Method Research Based on IaaS Cloud Platform

Jian Wan,Xianghong Yang,Zujie Ren,Zheng Ye 보안공학연구지원센터 2016 International Journal of Grid and Distributed Comp Vol.9 No.10

With the widespread use of cloud platforms, their performance evaluation tools also have become the research hot spot of academic circle. So far, many performance evaluation tools of the cloud platform have been designed in their corresponding application scenarios, which have brought much convenience on the performance evaluation and management of the cloud platform. In order to predict the maximum number of virtual machines that can be opened by the cloud platform, this paper integrates the current tools of performance evaluation and proposes a performance evaluation tool based on IaaS cloud platform. The key of the performance evaluation tool is that it not only can evaluate the performance of the cloud platform, but also can predict the maximum number of virtual machines that can be opened by the cloud platform when the configuration of the virtual machine and the workload of each virtual machine have been known. This special performance evaluation tool has not been put forward now. And, the prediction model has been introduced into this tool in this paper that is the most important and core part. Lastly, to test the effectiveness of cloud platform performance evaluation tool proposed in this paper, some tests have been done on the IaaS cloud platform. According to the contrast results of the forecast error among models, establishing support vector machine and neural network as single forecasting model. The results show combined model can be chosen as the prediction model of cloud platform performance evaluation tool.

Algorithm of Gaussian Sum Filter based on High-order UKF for Dynamic State Estimation

Lei Wang,Xianghong Cheng 제어·로봇·시스템학회 2015 International Journal of Control, Automation, and Vol.13 No.3

In this work we consider the state estimation problem in nonlinear/non-Gaussian systems. A new version of Gaussian sum estimation algorithm is developed here based on high-order unscented Kalman filter (HUKF). A sigma point selection method, high-order unscented transformation (HUT) technique is proposed for the HUKF, which can approximate the Gaussian distributions more accurately. We present the systematic formulation of Gaussian filters and develop efficient and accurate numerical integration of the optimal filter. We then go on to extend the use of the HUKF to discrete-time, nonlinear systems with additive, possibly non-Gaussian noise. The resulting filtering algorithm, called the Gaussian sum high-order unscented Kalman filter (GS-HUKF) approximates the predicted and posterior densities as a finite number of weighted sums of Gaussian densities. It is corroborated in the theoretical analysis and the simulation that the proposed Gaussian sum HUKF has integrated advantages with respect to computational accuracy and time complexity for nonlinear non-Gaussian filtering problems.