Construction of High Strain Rate Loading Constitutive Model and Failure Model and Prediction of Forming Limit for LA103Z Magnesium Alloy

Hailiang Yang,Xiao Wang,Peng Ni,Zhewen Li,Huixia Liu 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.8

In order to use numerical simulation to reveal the formability of magnesium–lithium alloys and other light alloys under highstrain rate, it is crucial to construct a constitutive model and a forming limit diagram (FLD) of LA103Z alloy that was formedby laser shock at high strain rate. In this study, three different uniaxial tensile experiments on the ultralight alloy materialLA103Z magnesium alloy were conducted, the mechanical behavior of the material with sensitivity to high strain rate wasstudied, and a Johnson–Cook (JC) constitutive model sensitive to high strain rates and suitable for laser shock forming wasproposed. At the same time, the constitutive parameters and failure parameters of the modified JC model of LA103Z magnesiumalloy were obtained through three different uniaxial tensile experiments. On the basis of the relationship betweentensile loading and stress–strain of LA103Z magnesium alloy, the experiments demonstrated the precision of the modified JCconstitutive model. A modified constitutive model was then developed by using the user material subroutine VUMAT, andthen it was applied to ABAQUS. Finally, the formability of the material was simulated, and the FLD of LA103Z magnesiumalloy material in laser shock forming was predicted. This study provides guidance on the actual production and applicationof LA103Z magnesium alloys.

Bioactive Ingredients from Nitraria tangutorun Bobr. Protect Against Cerebral Ischemia/Reperfusion Injury Through Attenuation of Oxidative Stress and the Inflammatory Response

Hailiang Wang,Jianhong Zhou,Hongtao Bi,Xiaoyu Yang,Wenlong Chen,Kuijun Jiang,Yang Yao,Weihua Ni 한국식품영양과학회 2021 Journal of medicinal food Vol.24 No.7

Nitraria tangutorun Bobr. has been used for thousands of years as a native folk medicine to alleviate dizziness and neurasthenia due to oxygen. In our previous study, natural antioxidant components (namely, NJBE) were isolated from industrial N. tangutorun Bobr. juice byproducts (NJBE) from the Qinghai-Tibet plateau. The current investigation assessed the effects of NJBE on ischemic stroke in mice and the potential mechanisms. C57BL/6 mice received NJBE (25, 50, or 100 mg/Kg) by gavage for 14 days and then stroke was induced by the middle cerebral artery occlusion (MCAO) model, followed by reperfusion for 72 h. The evaluation of brain infarct size, behavioral tests, and functional assessments was conducted to assess the effects of NJBE after MCAO. Our results suggested that NJBE significantly decreases infarct size, improves neurological deficits, as well as reduces the number of GFAP+ and Iba-1+ cells after MCAO. NJBE inhibited nitric oxide and malondialdehyde production in the ischemic brain. Meanwhile, it attenuated the expressions of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). Also, NJBE significantly attenuated the expression levels of proinflammatory indicators, including TNF-α, IL-1β, IL-6, and IL-12. This process was accompanied by the downregulation of TLR4, TRAF6, pIκB/pIκB, and MMP9 expression and the upregulation of claudin-5 expression. NJBE induced improvements in brain injury. The neuroprotective effect of NJBE provides evidence for its potential application in stroke treatment.

Erythropoietin-Modified Mesenchymal Stem Cells Enhance Anti-fibrosis Efficacy in Mouse Liver Fibrosis Model

Wang Xianyao,Wang Huizhen,Lu Junhou,Feng Zhanhui,Liu Zhongshan,Song Hailiang,Wang Heng,Zhou Yanhua,Xu Jianwei 한국조직공학과 재생의학회 2020 조직공학과 재생의학 Vol.17 No.5

BACKGROUND: Mesenchymal stem cell (MSC)-based cell transplantation is an effective means of treating chronic liver injury, fibrosis and end-stage liver disease. However, extensive studies have found that only a small number of transplanted cells migrate to the site of injury or lesion, and repair efficacy is very limited. METHODS: Bone marrow-derived MSCs (BM-MSCs) were generated that overexpressed the erythropoietin (EPO) gene using a lentivirus. Cell Counting Kit-8 was used to detect the viability of BM-MSCs after overexpressing EPO. Cell migration and apoptosis were verified using Boyden chamber and flow cytometry, respectively. Finally, the anti-fibrosis efficacy of EPO-MSCs was evaluated in vivo using immunohistochemical analysis. RESULTS: EPO overexpression promoted cell viability and migration of BM-MSCs without inducing apoptosis, and EPO-MSC treatment significantly alleviated liver fibrosis in a carbon tetrachloride (CCl4) induced mouse liver fibrosis model. CONCLUSION: EPO-MSCs enhance anti-fibrotic efficacy, with higher cell viability and stronger migration ability compared with treatment with BM-MSCs only. These findings support improving the efficiency of MSCs transplantation as a potential therapeutic strategy for liver fibrosis.

Hydrothermal Synthesis of CrO2 Nanoparticle Arrays on Ti nano-pit Array Templates

Xiaoling Wang,Lu Wang,Tao Lin,Hailiang Huang,Gehui Wen 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.1

Chromium dioxide (CrO2) nanoparticle arrays were fabricated on Ti nano-pit array templates by hydrothermal synthesis using CrO3 aqueous solution as precursor. The Ti nano-pit array template was obtained by stripping TiO2 nanotube array formed on the Ti foil. CrO2 nanoparticles are arranged in honeycomb pattern in a large area and their surface density reaches 1.5 x 10 10 cm -2. The CrO2 nanoparticle arrays show typical magnetic behavior, and the easy axis is parallel to the plane of Ti nano-pit array template. The influence of the concentration of CrO3 aqueous solution on the CrO2 nanoparticle arrays is studied and the mechanism of the formation of the CrO2 nanoparticle arrays is briefly discussed.

Exact Error Rate of Dual-Channel Receiver with Remote Antenna Unit Selection in Multicell Networks

( Qing Wang ),( Ju Liu ),( Lina Zheng ),( Hailiang Xiong ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.8

The error rate performance of circularly distributed antenna system is studied over Nakagami-m fading channels, where a dual-channel receiver is employed for the quadrature phase shift keying signals detection. To mitigate the Co-Channel Interference (CCI) caused by the adjacent cells and to save the transmit power, this work presents remote antenna unit selection transmission based on the best channel quality and the maximized path-loss, respectively. The commonly used Gaussian and Q-function approximation method in which the CCI and the noise are assumed to be Gaussian distributed fails to depict the precise system performance according to the central limit theory. To this end, this work treats the CCI as a random variable with random variance. Since the in-phase and the quadrature components of the CCI are correlated over Nakagami-m fading channels, the dependency between the in-phase and the quadrature components is also considered for the error rate analysis. For the special case of Rayleigh fading in which the dependency between the in-phase and the quadrature components can be ignored, the closed-form error rate expressions are derived. Numerical results validate the accuracy of the theoretical analysis, and a comparison among different transmission schemes is also performed.

Triptolide improves myocardial fibrosis in rats through inhibition of nuclear factor kappa B and NLR family pyrin domain containing 3 inflammasome pathway

Jianyao Shen,Hailiang Ma,Chaoquan Wang 대한생리학회-대한약리학회 2021 The Korean Journal of Physiology & Pharmacology Vol.25 No.6

Myocardial fibrosis (MF) is the result of persistent and repeated aggravation of myocardial ischemia and hypoxia, leading to the gradual development of heart failure of chronic ischemic heart disease. Triptolide (TPL) is identified to be involved in the treatment for MF. This study aims to explore the mechanism of TPL in the treatment of MF. The MF rat model was established, subcutaneously injected with isoproterenol and treated by subcutaneous injection of TPL. The cardiac function of each group was evaluated, including LVEF, LVFS, LVES, and LVED. The expressions of ANP, BNP, inflammatory related factors (IL-1β, IL-18, TNF-α, MCP-1, VCAM- 1), NLRP3 inflammasome factors (NLRP3, ASC) and fibrosis related factors (TGF-β1, COL1, and COL3) in rats were dete cted. H&E staining and Masson staining were used to observe myocardial cell inflammation and fibrosis of rats. Western blot was used to detect the p-P65 and t-P65 levels in nucleoprotein of rat myocardial tissues. LVED and LVES of MF group were significantly upregulated, LVEF and LVFS were significantly downregulated, while TPL treatment reversed these trends; TPL treatment downregulated the tissue injury and improved the pathological damage of MF rats. TPL treatment downregulated the levels of inflammatory factors and fibrosis factors, and inhibited the activation of NLRP3 inflammasome. Activation of NLRP3 inflammasome or NF-κB pathway reversed the effect of TPL on MF. Collectively, TPL inhibited the activation of NLRP3 inflammasome by inhibiting NF-κB pathway, and improved MF in MF rats.

FINITE GROUPS ALL OF WHOSE MAXIMAL SUBGROUPS ARE SB-GROUPS

Guo, Pengfei,Wang, Junxin,Zhang, Hailiang Korean Mathematical Society 2014 대한수학회보 Vol.51 No.4

A finite group G is called a SB-group if every subgroup of G is either s-quasinormal or abnormal in G. In this paper, we give a complete classification of those groups which are not SB-groups but all of whose proper subgroups are SB-groups.

In vitro disinfection efficacy and clinical protective effects of common disinfectants against acute hepatopancreatic necrosis disease (AHPND)- causing Vibrio isolates in Pacific white shrimp Penaeus vannamei

Zou Peizhuo,Yang Qian,Wang Hailiang,Xie Guosi,Cao Zhi,Chen Xing,Gao Wen,Huang Jie 한국미생물학회 2020 The journal of microbiology Vol.58 No.8

Acute hepatopancreatic necrosis disease (AHPND) is one of the most significant bacterial diseases in global shrimp culture, causing severe economic losses. In the present study, we carried out in vitro antimicrobial tests to investigate the disinfection efficacy of 14 common disinfectants toward different AHPND-causing Vibrio spp., including eight isolates of V. parahaemolyticus, four isolates of V. campbellii, and one isolate of V. owensii. Polyhexamethylene biguanidine hydrochloride (PHMB) was revealed to possess the strongest inhibitory activity. Through analyzing and evaluating the results of antimicrobial tests and acute toxicity test, we selected PHMB and hydrogen peroxide (H2O2) for further clinical protection test. Clinical manifestations indicated that both PHMB (2 mg/L and 4 mg/L) and H2O2 (12 mg/L) could effectively protect juvenile Penaeus vannamei from the infection of V. parahaemolyticus isolate Vp362 at 106 CFU/ml, and the survival rate was over 80%. When the bacterial concentration was reduced to 105 CFU/ml, 104 CFU/ml, and 103 CFU/ml, the survival rate after treated by 1 mg/L PHMB was 64.44%, 93.33%, and 100%, respectively. According to the results, PHMB and H2O2 showed a lower toxicity while a better protection activity, particularly against a lower concentration of the pathogens. Therefore, these two disinfectants are proved to be promising disinfectants that can be applied to prevent and control AHPND in shrimp culture. Moreover, the methods of this study also provided valuable information for the prevention of other important bacterial diseases and suggested a reliable means for screening potential drugs in aquaculture.

Reactive Radical Species in Photocatalytic Activities of PET-Ag-TiO2 Nanoparticles Composites Under Visible Light Irradiation

Hui Zhang,Dou Wang,Cuihong Sheng,Deping Ben,Hailiang Wu,Ningtao Mao 한국섬유공학회 2021 Fibers and polymers Vol.22 No.3

In this research, the reactive radical species in photocatalytic activities of a composite photocatalyst made fromPET filaments loaded with Ag-TiO2 nanoparticles under visible light irradiation, in comparison with those of as-modifiedAg-TiO2 nanoparticles, were reported and its photocatalytic mechanism was investigated. The PET filaments were modifiedby using tetrabutyl titanate as the TiO2 precursor and silver nitrate as the dopant in a hydrothermal process. The Ag decoratedTiO2 nanoparticles were synthesized and deposited on the surfaces of PET filaments in the hydrothermal process at 120 oCfor 180 min. The morphology, phase structure, chemical binding state, and optical properties of the PET-Ag-TiO2nanoparticles composites were systemically studied by means of field emission scanning electron microscopy (FESEM), X-raydiffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL)spectroscopy, diffuse reflectance spectroscopy (DRS), and ultraviolet photoelectron spectroscopy (UPS) techniques. Thephotocatalytic activities of the PET-Ag-TiO2 nanoparticles composites were evaluated in the photodegradation of bothmethylene blue (MB) and methyl orange (MO) dyes under visible light irradiation. It was found that, unlike in the asobtainedTiO2 nanoparticles and Ag decorated TiO2 nanoparticles, the photoinduced holes (h+) were the major reactiveradical species in both PET-Ag-TiO2 composite photocatalyst and the PET filaments loaded with TiO2 nanoparticles in theMB photodegradation process. The experimental results also indicated that the PET-Ag-TiO2 nanoparticles composites led tothe improvement of the separation efficiency of photogenerated electron-hole pairs. The enhanced photocatalytic activity ofthe PET filaments coated with Ag decorated TiO2 nanoparticles was ascribed to both the incorporation of Ag nanoparticlesinto TiO2 nanoparticles and the possible infiltration of Ag/Ti nanoparticles into PET polymers. In addition, the wavelengthand intensity of monochromatic light had great influences on the photodegradation rate of dye used, which was closelycorrelated with the maximum absorption wavelength of the dye to be degraded.

Finite groups all of whose maximal subgroups are SB-groups

Pengfei Guo,Junxin Wang,Hailiang Zhang 대한수학회 2014 대한수학회보 Vol.51 No.4

A finite group G is called a SB-group if every subgroup of G is either s-quasinormal or abnormal in G. In this paper, we give a complete classification of those groups which are not SB-groups but all of whose proper subgroups are SB-groups.