Apoptosis induced in vivo by new type gosling viral enteritis virus

Shun Chen,Anchun Cheng,Mingshu Wang,Dekang Zhu,Renyong Jia,Qihui Luo,Hengmin Cui,Yi Zhou,Yin Wang,Zhiwen Xu,Zhengli Chen,Xiaoyue Chen,Xiaoyu Wang 대한수의학회 2011 JOURNAL OF VETERINARY SCIENCE Vol.12 No.4

In this study, apoptosis was induced by new type gosling viral enteritis virus (NGVEV) in experimentally infected goslings is reported in detail for the first time. After 3-day-old goslings were orally inoculated with a NGVEV-CN strain suspension, the time course of NGVEV effects on apoptotic morphological changes of the internal tissues was evaluated. These changes were observed by histological analysis with light microscopy and ultrastructural analysis with transmission electron microscopy. DNA fragmentation was assessed with a terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay and DNA ladder analysis. A series of characteristic apoptotic morphological changes including chromatin condensation and margination, cytoplasmic shrinkage, plasma membrane blebbing, and formation of apoptotic bodies were noted. Apoptosis was readily observed in the lymphoid and gastrointestinal organs, and sporadically occurred in other organs after 3 days post-infection (PI). The presence and quantity of TUNEL-positive cells increased with infection time until 9 days PI. DNA extracted from the NGVEV-infected gosling cells displayed characteristic 180~200 bp ladders. Apoptotic cells were ubiquitously distributed, especially among lymphocytes, macrophages, monocytes, and epithelial and intestinal cells. Necrosis was subsequently detected during the late NGVEV-infection phase, which was characterized by cell swelling, plasma membrane collapse, and rapidly lysis. Our results suggested that apoptosis may play an important role in the pathogenesis of NGVE disease.

Evidence of a gate-tunable Mott insulator in a trilayer graphene moiré superlattice

Chen, Guorui,Jiang, Lili,Wu, Shuang,Lyu, Bosai,Li, Hongyuan,Chittari, Bheema Lingam,Watanabe, Kenji,Taniguchi, Takashi,Shi, Zhiwen,Jung, Jeil,Zhang, Yuanbo,Wang, Feng NATURE PUBLISHING GROUP 2019 NATURE PHYSICS Vol.15 No.3

Vision measurement of gear pitting based on DCGAN and U-Net

Zhiwen Wang,Yi Qin,Weiwei Chen 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.7

To quantitatively detect the gear pitting, this paper proposes a vision measurement method based on deep convolutional generative adversarial network (DCGAN) and fully convolutional segmentation network (U-Net) for measuring the area ratio of gear pitting. A machine vision system is designed to automatically collect the pitting images of all gear teeth obtained from gear fatigue tests, but the pitting images are not sufficient due to the high cost of gear fatigue test. To solve the problem of small sample, DCGAN is applied to expand pitting samples. By the expansive sample set, the edge detection algorithm and U-Net are respectively used to segment the tooth surface and pitting. The proposed approach is applied to measure the gear pitting, and a comprehensive evaluation index is designed to evaluate the performance of gear pitting detection. Experimental results show that the average relative error and the absolute error of pitting area ratio obtained by the proposed method are respectively 7.83 % and 0.18 %, which are much lower than those obtained by the conventional detection method without sample augmentation. Thus, the proposed method has satisfactory accuracy and precede the detection method without sample augmentation.

Performance evaluation of inerter-based damping devices for structural vibration control of stay cables

Zhiwen Huang,Xugang Hua,Zhengqing Chen,Huawei Niu 국제구조공학회 2019 Smart Structures and Systems, An International Jou Vol.23 No.6

Inerter-based damping devices (IBBDs), which consist of inerter, spring and viscous damper, have been extensively investigated in vehicle suspension systems and demonstrated to be more effective than the traditional control devices with spring and viscous damper only. In the present study, the control performance on cable vibration reduction was studied for four different inerter-based damping devices, namely the parallel-connected viscous mass damper (PVMD), series-connected viscous mass damper (SVMD), tuned inerter dampers (TID) and tuned viscous mass damper (TVMD). Firstly the mechanism of the ball screw inerter is introduced. Then the state-space formulation of the cable-TID system is derived as an example for the cable-IBBDs system. Based on the complex modal analysis, single-mode cable vibration control analysis is conducted for PVMD, SVMD, TID and TVMD, and their optimal parameters and the maximum attainable damping ratios of the cable/damper system are obtained for several specified damper locations and modes in combination by the Nelder-Mead simplex algorithm. Lastly, optimal design of PVMD is developed for multi-mode vibration control of cable, and the results of damping ratio analysis are validated through the forced vibration analysis in a case study by numerical simulation. The results show that all the four inerter-based damping devices significantly outperform the viscous damper for single-mode vibration control. In the case of multi-mode vibration control, PVMD can provide more damping to the first four modes of cable than the viscous damper does, and their maximum control forces under resonant frequency of harmonic forced vibration are nearly the same. The results of this study clearly demonstrate the effectiveness and advantages of PVMD in cable vibration control.

AcuD Gene Knockout Attenuates the Virulence of Talaromyces marneffei in a Zebrafish Model

( Jiao Feng ),( Zhiwen Chen ),( Liya He ),( Xing Xiao ),( Chunmei Chen ),( Jieming Chu ),( Eleftherios Mylonakis ),( Liyan Xi ) 한국균학회 2019 Mycobiology Vol.47 No.2

Talaromyces marneffei is the only dimorphic species in its genus and causes a fatal systemic mycosis named talaromycosis. Our previous study indicated that knockdown of AcuD gene (encodes isocitrate lyase of glyoxylate bypass) of T. marneffei by RNA interference approach attenuated the virulence of T. marneffei, while the virulence of the AcuD knockout strains was not studied. In this study, T. marneffei-zebrafish infection model was successfully established through hindbrain microinjection with different amounts of T. marneffei yeast cells. After co-incubated at 28_C, the increasing T. marneffei inoculum doses result in greater larval mortality; and hyphae generation might be one virulence factor involved in T. marneffeizebrafish infection. Moreover, the results demonstrated that the virulence of the DAcuD was significantly attenuated in this Zebrafish infection model.

Three-Dimensional Porous Carbon Nanotube Papers as Current Collector and Buffer for SnO2 Anodes

Xiaogang Sun,Zhiwen Qiu,Long Chen,Manyuan Cai,Jie Wang,Xu Li,Wei Chen,Zhenhong Liu,Hao Tang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.11

A novel three-dimensional porous conductive papers have been successfully synthesized via a simple physical route. Multi-walled carbon nanotubes (MWCNTs)@SnO2 composite anode materials are embedded in porous conductive papers. The peculiar structure can accommodate the huge volume expansion of MWCNTs@SnO2 composite anode materials during charge–discharge process. The framework formed by MWCNTs and cellulose can greatly improve the strength, stability and flexibility of the electrode. In addition, the structure successfully prevent the aggregation of SnO2 nanoparticles and collapse of MWCNTs@SnO2 composite electrode, leading to the improvement in electrochemical utilization and stable cyclability. The samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM), respectively. The electrochemical properties and application were evaluated by galvanostatic discharge–charge testing and cycling voltammetry. As a result, the MWCNTs@SnO2 composite electrode showed excellent rate performance. The discharge capacity remains about 680mAh g -1 after 100 cycles at 200mA g -1, and even around 300mAh g -1 at 1000mA g -1.

Dynamic characteristic parameters identification analysis of a parallel manipulator with flexible links

Chunxia Zhu,Jing Wang,Zhiwen Chen,Bo Liu 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.12

This paper presents dynamic parameters identification analysis of a 3-TPT parallel manipulator with flexible links by means of simulationand experiment. The 3-TPT mechanism is described in detail, and the dynamic equations of the regarded mechanism are derivedanalytically based on the Newton’s second law. The dynamic simulation model of parallel manipulator with flexible links is built by theintegration method of virtual prototyping (VP) and finite element analysis (FEA), which forms the flexible multi-body system of parallelmanipulator. Frequency response curves are obtained by applied force on the simulation model, and the stiffness and damping ratio areidentified, respectively, from the simulation results. The strategy has been experimentally tested on an actual 3-TPT parallel manipulator. The compared results show that the errors are very small and reasonable scope, so it is feasible for the integration method used as referenceand basis for dynamic characteristic. Therefore, the integration simulation method provides a theoretical foundation and referencefor dynamic optimal design of parallel manipulator. These analyses and results provide valuable insight into the design and control of theparallel manipulator with flexible links.

Feasibility study of buckling-restrained braces with PM-35 steel core

Chao Zhao,Qianqian Chen,Xingu Zhong,Tianyu Zhang,Zhiwen Chen 국제구조공학회 2021 Structural Engineering and Mechanics, An Int'l Jou Vol.79 No.2

The energy dissipation characteristics of core materials greatly influence the working performance of bucklingrestrained braces (BRBs), so it is a vital work to develop more excellent energy dissipation core materials. In this research, a series of experimental studies are conducted, including the mechanical properties of PM-35 steels and the working performance of PM-35 BRB specimens, which serve to investigate the feasibility of PM-35 steel as core materials of BRBs. In addition, the analysis of variance (ANOVA) has been conducted to study the sensitivity factors of energy dissipation of PM-35 BRB specimens, especially the pre-force applied on the BRB specimens. According to the results of this research, it can be concluded that the energy absorption efficiency of PM-35 BRBs specimens is much higher than that of BRB specimens with ordinary core materials; the internal pores greatly weaken the yield strength of PM-35 steel and obviously improve the plastic deformation capacity, which makes that PM-35 core materials are able to absorb energy in a lower stress level; pre-force applied on core materials is the key factor governing the energy absorption, and can significantly improve the working performance of BRB specimens with PM-35 core materials.

Electrochemical Performance of Lithium-Ion Capacitors Using Pre-Lithiated Multiwalled Carbon Nanotubes as Anode

Manyuan Cai,Xiaogang Sun,Yanyan Nie,Wei Chen,Zhiwen Qiu,Long Chen,Zhenhong Liu,Hao Tang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.4

Pre-lithiated multiwalled carbon nanotube anode was prepared by internal short circuit approach (ISC) for 5 min, 30 min, 60 min and 120 min respectively. Lithium ion capacitors (LICs) were assembled by using pre-lithiated multiwalled carbon nanotubes as anodes and activated carbon (AC) as cathodes. The structure of multiwalled carbon nanotubes and electrodes were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical performance of pre-lithiated multiwalled carbon nanotube electrodes and pristine carbon nanotube electrodes were tested by galvanostatic charge/discharge and electrochemical impedance. The results indicated that pre-lithiation carbon nanotubes greatly improved the charge/discharge performance of LICs. The energy density was four times than conventional electric double-layer capacitors (EDLCs) at the current density of 100 mA/g. The LICs achieved a specific capacitance of 59.3 F/g at the current density of 100 mA/g with 60 min pre-lithiatiation process. The maximum energy density and power density was 96Wh/kg and 4035W/kg, respectively. The energy density still remained about 89.0% after 1000 cycles. The LIC showed excellent supercapacitor performance.

Effect of Glucagon-like Peptide 2 on Tight Junction in Jejunal Epithelium of Weaned Pigs though MAPK Signaling Pathway

Yu, Changsong,Jia, Gang,Jiang, Yi,Deng, Qiuhong,Chen, Zhengli,Xu, Zhiwen,Chen, Xiaolin,Wang, Kangning Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.5

The glucagon-like peptide 2 (GLP-2) that is expressed in intestine epithelial cells of mammals, is important for intestinal barrier function and regulation of tight junction (TJ) proteins. However, there is little known about the intracellular mechanisms of GLP-2 in the regulation of TJ proteins in piglets' intestinal epithelial cells. The purpose of this study is to test the hypothesis that GLP-2 regulates the expressions of TJ proteins in the mitogen-activated protein kinase (MAPK) signaling pathway in piglets' intestinal epithelial cells. The jejunal tissues were cultured in a Dulbecco's modified Eagle's medium/high glucose medium containing supplemental 0 to 100 nmol/L GLP-2. At 72 h after the treatment with the appropriate concentrations of GLP-2, the mRNA and protein expressions of zonula occludens-1 (ZO-1), occludin and claudin-1 were increased (p<0.05). U0126, an MAPK kinase inhibitor, prevented the mRNA and protein expressions of ZO-1, occludin, claudin-1 increase induced by GLP-2 (p<0.05). In conclusion, these results indicated that GLP-2 could improve the expression of TJ proteins in weaned pigs' jejunal epithelium, and the underlying mechanism may due to the MAPK signaling pathway.