Packaging of Rift Valley fever virus pseudoviruses and establishment of a neutralization assay method

Yuetao Li,Yongkun Zhao,Cuiling Wang,Xuexing Zheng,Hualei Wang,Weiwei Gai,Hongli Jin,Feihu Yan,Boning Qiu,Yuwei Gao,Nan Li,Songtao Yang,Xianzhu Xia 대한수의학회 2018 Journal of Veterinary Science Vol.19 No.2

Rift Valley fever (RVF) is an acute, febrile zoonotic disease that is caused by the RVF virus (RVFV). RVF is mainly prevalent on the ArabianPeninsula, the African continent, and several islands in the Indian Ocean near southeast Africa. RVFV has been classified by the WorldOrganisation for Animal Health (OIE) as a category A pathogen. To avoid biological safety concerns associated with use of the pathogen inRVFV neutralization assays, the present study investigated and established an RVFV pseudovirus-based neutralization assay. This study usedthe human immunodeficiency virus (HIV) lentiviral packaging system and RVFV structural proteins to successfully construct RVFVpseudoviruses. Electron microscopy observation and western blotting indicated that the size, structure, and shape of the packagedpseudoviruses were notably similar to those of HIV lentiviral vectors. Infection inhibition assay results showed that an antibody against RVFVinhibited the infective ability of the RVFV pseudoviruses, and an antibody neutralization assay for RVFV detection was then established. Thisstudy has successfully established a neutralization assay based on RVFV pseudoviruses and demonstrated that this method can be used toeffectively evaluate antibody neutralization.

A new interval perturbation method for static structural response bounds using radial basis neural network differentiation

Yuwei Yao,Liqun Wang,Guolai Yang,Fengjie Xu,Lei Li 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.3

The interval perturbation method is an effective and successful tool in the uncertainty analysis; however, it suffers from the deficiency in the required differential information, which limits its application in complex engineering problems. To end this, this paper uses the radial basis neural network to formulate the derivative information, and its fine accuracy is demonstrated by a mathematical example. Moreover, a new interval analysis method combining interval perturbation and radial basis neural network differentiation, abbreviated as RBNNIPM is proposed. Furthermore, RBNNIPM is applied to calculate the boundaries of yield stress in a three-bar truss, and the detailed assessment proves that RBNNIPM has both high efficiency and high precision. Finally, an electromagnetic buffer model is established to certificate the practicability of RBNNIPM in practical engineering.

Provisional Microgrid Frequency Regulation by Brain Emotional Learning Based Intelligent Controller and Implementation Through FPGA

Li Zhufeng,Gao Jie,Yang Yuwei 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.3

With the advancement of technology and human movement towards evolution, intelligent control methods are becoming more important. One of the areas of progress is related to the development of new frameworks for electricity generation and distribution systems, and the microgrid structure with economic capabilities is one of the frameworks. Accordingly, this paper presents a new practical method for controlling the frequency of microgrids and is able to cover the following issues at the same time. 1- It considers the nonlinear model of provisional microgrid which has a hybrid structure (AC and DC) in addition to renewable energy sources. 2- Introduces a method for microgrid frequency control under different operational conditions that performs based on the brain emotional learning. 3- Ensures the operation and applicability of the control method for the provisional microgrid through implementation of FPGA for the first time 4- Confirms the robustness of the proposed method under extreme load changes. So, in the simulation scenarios, the effects of wind turbine and solar energy are considered and under the influence of various changes in load and system uncertainties, the robustness and efficiency of the proposed method are well demonstrated. With the advancement of technology and human movement towards evolution, intelligent control methods are becoming more important. One of the areas of progress is related to the development of new frameworks for electricity generation and distribution systems, and the microgrid structure with economic capabilities is one of the frameworks. Accordingly, this paper presents a new practical method for controlling the frequency of microgrids and is able to cover the following issues at the same time. 1- It considers the nonlinear model of provisional microgrid which has a hybrid structure (AC and DC) in addition to renewable energy sources. 2- Introduces a method for microgrid frequency control under diferent operational conditions that performs based on the brain emotional learning. 3- Ensures the operation and applicability of the control method for the provisional microgrid through implementation of FPGA for the frst time 4- Confrms the robustness of the proposed method under extreme load changes. So, in the simulation scenarios, the efects of wind turbine and solar energy are considered and under the infuence of various changes in load and system uncertainties, the robustness and efciency of the proposed method are well demonstrated.

A Coordinative Control Strategy for Power Electronic Transformer Based Battery Energy Storage Systems

Yuwei Sun,Jiaomin Liu,Yonggang Li,Chao Fu,Yi Wang 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.6

A power electronic transformer (PET) based on the cascaded H-bridge (CHB) and the isolated bidirectional DC/DC converter (IBDC) is capable of accommodating a large scale battery energy storage system (BESS) in the medium-voltage grid, and is referred to as a power electronic transformer based battery energy storage system (PET-BESS). This paper investigates the PET-BESS and proposes a coordinative control strategy for it. In the proposed method, the CHB controls the power flow and the battery state-of-charge (SOC) balancing, while the IBDC maintains the dc-link voltages with feedforward implementation of the power reference and the switch status of the CHB. State-feedback and linear quadratic Riccati (LQR) methods have been adopted in the CHB to control the grid current, active power and reactive power. A hybrid PWM modulating method is utilized to achieve SOC balancing, where battery SOC sorting is involved. The feedforward path of the power reference and the CHB switch status substantially reduces the dc-link voltage fluctuations under dynamic power variations. The effectiveness of the proposed control has been verified both by simulation and experimental results. The performance of the PET-BESS under bidirectional power flow has been improved, and the battery SOC values have been adjusted to converge.

Optimization for testing conditions of inverse gas chromatography and surface energies of various carbon fiber bundles

Liu Yuwei,Gu Yizhuo,Wang Shaokai,Li Min 한국탄소학회 2023 Carbon Letters Vol.33 No.3

Surface free energy is an important parameter in surface and interface properties of fiber reinforced polymer composite. The BET (Brunauer, Emmett, and Teller) surface area and surface energy of the sample can be obtained by Inverse Gas Chromatography (IGC) based on the adsorption principle. In this paper, surface energy of carbon fiber bundle was tested by means of IGC under different conditions to find reliable test parameters. The main parameters involved include length, mass, and packing density of sample, target fractional surface coverage, flow rate, and maximum elution time. It is demonstrated that IGC has the advantages of simple sample preparation, stable test data, high automation, and high sensitivity for carbon fiber. Among all test conditions, packing density and flow rate have the greatest influences on the experimental results. The optimized test parameters are suitable for various kinds of carbon fiber bundles, including polyacrylonitrile-based and pitch-based carbon fibers with different tensile properties and tow sizes. Moreover, IGC can acutely characterize the surface properties of carbon fibers after carbon nanotube modification and heat treatment, which are hard to carry out using contact angle method.

A Coordinative Control Strategy for Power Electronic Transformer Based Battery Energy Storage Systems

Sun, Yuwei,Liu, Jiaomin,Li, Yonggang,Fu, Chao,Wang, Yi The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.6

A power electronic transformer (PET) based on the cascaded H-bridge (CHB) and the isolated bidirectional DC/DC converter (IBDC) is capable of accommodating a large scale battery energy storage system (BESS) in the medium-voltage grid, and is referred to as a power electronic transformer based battery energy storage system (PET-BESS). This paper investigates the PET-BESS and proposes a coordinative control strategy for it. In the proposed method, the CHB controls the power flow and the battery state-of-charge (SOC) balancing, while the IBDC maintains the dc-link voltages with feedforward implementation of the power reference and the switch status of the CHB. State-feedback and linear quadratic Riccati (LQR) methods have been adopted in the CHB to control the grid current, active power and reactive power. A hybrid PWM modulating method is utilized to achieve SOC balancing, where battery SOC sorting is involved. The feedforward path of the power reference and the CHB switch status substantially reduces the dc-link voltage fluctuations under dynamic power variations. The effectiveness of the proposed control has been verified both by simulation and experimental results. The performance of the PET-BESS under bidirectional power flow has been improved, and the battery SOC values have been adjusted to converge.

Effect of Lactic Acid on the Photoelectrocatalytic Water Splitting of Hematite Prepared by Hydrothermal Method

Longzhu Li,Huidong Tang,Yuwei Chen,Rong Yang,Daxiang Tian,Zhidong Chen 대한금속·재료학회 2020 ELECTRONIC MATERIALS LETTERS Vol.16 No.5

The photoelectrocatalytic water splitting performance of the pristine hematite is limited because of its poor bulk chargeseparation efficiency. In this study, the lactic acid modified hematite films were grown in situ on Fluorine-doped tin oxidesubstrates by hydrothermal method and then annealed in nitrogen atmosphere. At 1.5 V versus RHE, the photocurrent densityof the optimal lactic acid modified hematite photoanode (0.075LA-Fe2O3) was 1.5 mA cm−2, which was three times that ofthe based hematite (0.5 mA cm−2). The enhanced photoelectrocatalytic performance of the lactic acid modified hematitewas attributed to its increased bulk charge separation efficiency caused by the oxygen vacancies and island-like pattern, aswell as its improved surface charge injection efficiency. The effect of lactic acid on the morphology, crystalline structure andphotoelectrocatalytic performance of the hematite photoanode are studied by systematical characterization.

Seismic behavior of rebar-penetrated joint between GCFST column and RGC beam

Guochang Li,Chen Fang,Yuwei An,Xing Zhao 국제구조공학회 2015 Steel and Composite Structures, An International J Vol.19 No.3

The paper makes the experimental and finite-element-analysis investigation on the seismic behavior of the rebar-penetrated joint between gangue concrete filled steel tubular column and reinforced gangue concrete beam under low cyclic reversed loading. Two specimens are designed and conducted for the experiment to study the seismic behavior of the rebar-penetrated joint under cyclic loading. Then, finite element analysis models of the rebar-penetrated joint are developed using ABAQUS 6.10 to serve as the complement of the experiment and further analyze the seismic behavior of the rebar-penetrated joint. Finite element analysis models are also verified by the experimental results. Finally, the hysteretic performance, the bearing capacity, the strength degradation, the rigidity degradation, the ductility and the energy dissipation of the rebar-penetrated joint are evaluated in detail to investigate the seismic behavior of the rebar-penetrated joint through experimental results and finite element analysis results. The research demonstrates that the rebar-penetrated joint between gangue concrete filled steel tubular column and reinforced gangue concrete beam, with full and spindle-shaped load-displacement hysteretic curves, shows generally the high ductility and the outstanding energy-dissipation capacity. As a result, the rebar-penetrated joint exhibits the excellent seismic performance and meets the earthquake-resistant requirements of the codes in China. The research provides some references and suggestions for the application of the rebar-penetrated joint in the projects.

BF-30 effectively inhibits ciprofloxacin-resistant bacteria in vitro and in a rat model of vaginosis

Wang, Jing,Li, Bing,Li, Yang,Dou, Jie,Hao, Qingru,Tian, Yuwei,Wang, Hui,Zhou, Changlin 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.7

Bacterial infections are becoming increasingly difficult to treat due to the increasing number of multidrug-resistant strains. Cathelicidin-BF (BF-30) is a cathelicidin-like antimicrobial peptide and exhibits broad antimicrobial activity against bacteria. In the present study, the antibacterial activity of BF-30 against ciprofloxacin-resistant Escherichia coli and Staphylococcus aureus was examined, and the protective effects of this peptide against these bacteria in rats with bacterial vaginosis were identified for the first time. The data showed that BF-30 had effective antimicrobial activities against ciprofloxacin-resistant E. coli and S. aureus. The minimal inhibitory concentrations for both bacterial strains were $16{\mu}g/ml$, and the minimal bactericidal concentrations were 64 and $128{\mu}g/ml$, respectively. A time course experiment showed that the CFU counts rapidly decreased after BF-30 treatment, and the bacteria were nearly eliminated within 4 h. BF-30 could reduce the fold change (CFU/ml) in local colonization by drug-resistant E. coli and S. aureus to 0.01 at a dose of 0.8 mg/kg/day in the rats' vaginal secretions. In addition, BF-30 induced membrane permeabilization and bound to the genomic DNA, interrupting protein synthesis. Taken together, our data demonstrate that BF-30 has potential therapeutic value for the prevention and treatment of bacterial vaginosis.

Weight Estimation and Secure Control for Discrete Stochastic Distribution Control Systems Under Sparse Sensor Attacks

Xiaoyun Yi,Yuwei Ren,Li Qi,Ben Niu,Yixian Fang 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.4

In this paper, we investigate the problem of weight estimation and secure control for discrete stochastic distribution control (SDC) systems under sparse sensor attacks. Firstly, a Luenberger observer is designed for the linear SDC systems to perform the weight estimation under sparse sensor attacks. Then, a generalized proportionalintegral (PI) tracking control strategy is proposed for the linear B-spline model. Furthermore, the tracking problem for output probability density functions (PDFs) is implemented, and the designed controller ensures that the closedloop system is stable. Finally, the simulation results show the effectiveness of the proposed method.