Effect of carbon black on properties of 0–3 piezoelectric ceramic/cement composites

Huang Shifeng,Li Xue,Liu Futian,Chang Jun,Xu Dongyu,Cheng Xin 한국물리학회 2009 Current Applied Physics Vol.9 No.6

0–3 cement-based piezoelectric composites were fabricated using sulphoaluminate cement and piezoelectric ceramic [0.08Pb(Li1/4Nb3/4)O3 . 0.47PbTiO3 . 0.45PbZrO3] [P(LN)ZT] as raw materials by compressing technique. The influences of carbon black content on the piezoelectric and dielectric properties, electric conductivity and impedance were investigated. The results indicate that the piezoelectric strain constant d33 and piezoelectric voltage constant g33 of the composites increase gradually with a suitable carbon black addition. When the carbon black content is 0.3 wt%, both of the piezoelectric strain constant d33 and piezoelectric voltage constant g33 of the composite exist the maximum value, which are 17.45 pC N-1 and 36.3 mV m N-1, respectively. As the carbon black content increases, the dielectric constant εr, dielectric loss tanδ and electric conductivity σ of the composites all increase, while the impedance decreases. In the frequency range tested, the more the carbon black content, the higher the εr value. The planar electromechanical coupling coefficient Kp, the thickness electromechanical coupling coefficient Kt and the mechanical quality factor Qm are almost unaffected by the carbon black content.

Microstructure evolution and enhanced vacuum tribological performance of Ni-doped WS₂ composite coating

Xu, Shu-Sheng,Weng, Li-Jun,Liu, Yu-Zhen,Kang, Kyeong-Hee,Kim, Chang-Lae,Kim, Dae-Eun Elsevier Sequoia 2017 Surface & coatings technology Vol.325 No.-

<P><B>Abstract</B></P> <P>Ni-doped WS<SUB>2</SUB> composite coatings with various Ni contents were co-deposited using a radio frequency sputtering system on silicon wafer and AISI 440C stainless steel substrates. The microstructural characteristics of the WS<SUB>2</SUB>-Ni composite coatings and their tribological properties in vacuum were assessed. During introduction of Ni dopant in the WS<SUB>2</SUB>-Ni composite coating the sulfur/tungsten (S/W) ratio in the coating increased due to reduced preferential resputtering of sulfur atoms in the growing coating. The microstructure of the WS<SUB>2</SUB>-Ni composite coating varied from a fine columnar structure for Ni content equal to or less than 7.7at.% to a featureless structure as the Ni content increased further. The Ni dopant inhibited the growth of the coarse columnar WS<SUB>2</SUB> platelets which was accompanied by nanocrystallization and amorphization of the composite coating structure. WS<SUB>2</SUB>-Ni composite coatings with fine columnar structure exhibited relatively low hardness but showed a high tendency to form a lubricating transfer layer. It also demonstrated low brittleness and prolonged wear life in vacuum condition compared to coatings with dense featureless structure. The variation in tribological performance between the composite coatings resulted from the different wear mechanisms associated with their distinct microstructures.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Microstructure of WS<SUB>2</SUB> coating was modified by incorporating Ni as a dopant. </LI> <LI> The introduction of Ni increased the S/W ratio of the WS<SUB>2</SUB> composite coating. </LI> <LI> High Ni content in the WS<SUB>2</SUB> coating led to high brittleness and low wear resistance. </LI> <LI> WS<SUB>2</SUB>–5at.% Ni coating showed 5 times longer wear life than pure WS<SUB>2</SUB> film in vacuum. </LI> <LI> Superior tribological properties were attributed to transfer layer and high hardness. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Effects of G-Rh2 on mast cell-mediated anaphylaxis via AKT-Nrf2/NF-κB and MAPK-Nrf2/NF-κB pathways

Chang Xu,Liangchang Li,Chongyang Wang,Jingzhi Jiang,Li Li,Lianhua Zhu,Shan Jin,Zhehu Jin,Jung Joon Lee,Guanhao Li,Guanghai Yan 고려인삼학회 2022 Journal of Ginseng Research Vol.46 No.4

Background: The effect of ginsenoside Rh2 (G-Rh2) on mast cell-mediated anaphylaxis remains unclear. Herein, we investigated the effects of G-Rh2 on OVA-induced asthmatic mice and on mast cell-mediatedanaphylaxis. Methods: Asthma model was established for evaluating airway changes and ear allergy. RPMCs and RBL-2H3 were used for in vitro experiments. Calcium uptake, histamine release and degranulation weredetected. ELISA and Western blot measured cytokine and protein levels, respectively. Results: G-Rh2 inhibited OVA-induced airway remodeling, the production of TNF-a, IL-4, IL-8, IL-1b andthe degranulation of mast cells of asthmatic mice. G-Rh2 inhibited the activation of Syk and Lyn in lungtissue of OVA-induced asthmatic mice. G-Rh2 inhibited serum IgE production in OVA induced asthmaticmice. Furthermore, G-Rh2 reduced the ear allergy in IgE-sensitized mice. G-Rh2 decreased the earthickness. In vitro experiments G-Rh2 significantly reduced calcium uptake and inhibited histaminerelease and degranulation in RPMCs. In addition, G-Rh2 reduced the production of IL-1b, TNF-a, IL-8, andIL-4 in IgE-sensitized RBL-2H3 cells. Interestingly, G-Rh2 was involved in the FcεRI pathway activation ofmast cells and the transduction of the Lyn/Syk signaling pathway. G-Rh2 inhibited PI3K activity in adose-dependent manner. By blocking the antigen-induced phosphorylation of Lyn, Syk, LAT, PLCg2, PI3KERK1/2 and Raf-1 expression, G-Rh2 inhibited the NF-kB, AKT-Nrf2, and p38MAPK-Nrf2 pathways. However, G-Rh2 up-regulated Keap-1 expression. Meanwhile, G-Rh2 reduced the levels of p-AKT,p38MAPK and Nrf2 in RBL-2H3 sensitized IgE cells and inhibited NF-kB signaling pathway activation byactivating the AKT-Nrf2 and p38MAPK-Nrf2 pathways. Conclusion: G-Rh2 inhibits mast cell-induced allergic inflammation, which might be mediated by theAKT-Nrf2/NF-kB and p38MAPK-Nrf2/NF-kB signaling pathways

Stress-induced expression of the sweetpotato gene <i>IbLEA14</i> in poplar confers enhanced tolerance to multiple abiotic stresses

Ke, Qingbo,Park, Sung-Chul,Ji, Chang Yoon,Kim, Ho Soo,Wang, Zhi,Wang, Shiwen,Li, Hongbing,Xu, Bingcheng,Deng, Xiping,Kwak, Sang-Soo Elsevier 2018 Environmental and experimental botany Vol.156 No.-

<P><B>Abstract</B></P> <P>Late embryogenesis abundant (LEA) proteins are small, highly hydrophilic proteins that act as protectors of macromolecules and increase abiotic stress tolerance in plants. We previously reported that overexpressing sweetpotato <I>IbLEA14</I> under the control of the <I>CaMV 35S</I> promoter increased osmotic and salt stress tolerance in transgenic sweetpotato calli. In this study, we generated transgenic poplar plants (<I>Populus alba × P. glandulosa</I>) expressing <I>IbLEA14</I> under the control of the oxidative stress-inducible <I>SWPA2</I> promoter (referred to as SL plants). Among the 15 SL plants obtained, three lines (SL2, SL7, and SL12) were established based on <I>IbLEA14</I> transcript levels, tolerance to salt stress and Southern blot analysis. The SL plants exhibited less damage in response to methyl viologen-mediated oxidative stress than non-transgenic (NT) plants. SL plants also showed enhanced tolerance to drought, salt, and heat stress, which was associated with higher photosystem II efficiency and lower malondialdehyde levels compared with NT plants. Furthermore, SL plants had higher levels of monolignol biosynthesis-related gene transcripts under drought stress compared with NT plants. Finally, SL plants exhibited increased tolerance to heat stress, which is associated with the high thermostability of IbLEA14 protein. SL plants might be useful for reforestation on global marginal lands, including desertification and reclaimed areas.</P> <P><B>Highlights</B></P> <P> <UL> <LI> <I>IbLEA14</I> gene was transformed into poplar plants. </LI> <LI> Transgenic poplars exhibit increased tolerance to MV-mediated oxidative, drought, salt and heat stress. </LI> <LI> Overproduction of IbLEA14 affects lignification and thermostability of transgenic poplars. </LI> </UL> </P>

Tim-3 Expression by Peripheral Natural Killer Cells and Natural Killer T Cells Increases in Patients with Lung Cancer - Reduction after Surgical Resection

Xu, Li-Yun,Chen, Dong-Dong,He, Jian-Ying,Lu, Chang-Chang,Liu, Xiao-Guang,Le, Han-Bo,Wang, Chao-Ye,Zhang, Yong-Kui Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.22

Background: The purpose of this study was to investigate Tim-3 expression on peripheral CD3-CD56+ natural killer (NK) cells and CD3+CD56+ natural killer T (NKT) cells in lung cancer patients. Materials and Methods: We analyzed Tim-3+CD3-CD56+ cells, Tim-3+CD3-$CD56^{dim}$ cells, Tim-3+CD3-$CD56^{bright}$ cells, and Tim-3+CD3+CD56+ cells in fresh peripheral blood from 79 lung cancer cases preoperatively and 53 healthy controls by flow cytometry. Postoperative blood samples were also analyzed from 21 members of the lung cancer patient cohort. Results: It was showed that expression of Tim-3 was significantly increased on CD3-CD56+ cells, CD3-$CD56^{dim}$ cells and CD3+CD56+ cells in lung cancer patients as compared to healthy controls (p=0.03, p=0.03 and p=0.04, respectively). When analyzing Tim-3 expression with cancer progression, results revealed more elevated Tim-3 expression in CD3-CD56+ cells, CD3-$CD56^{dim}$ cells and CD3+CD56+ cells in cases with advanced stages (III/IV) than those with stage I and II (p=0.02, p=0.04 and p=0.01, respectively). In addition, Tim-3 expression was significantly reduced on after surgical resection of the primary tumor (p<0.01). Conclusions: Tim-3 expression in natural killer cells from fresh peripheral blood may provide a useful indicator of disease progression of lung cancer. Furthermore, it was indicated that Tim-3 might be as a therapeutic target.

Pseudonocardia rhizophila sp. nov., a novel actinomycete isolated from a rhizosphere soil

Li, Jie,Zhao, Guo-Zhen,Huang, Hai-Yu,Zhu, Wen-Yong,Lee, Jae-Chan,Kim, Chang-Jin,Xu, Li-Hua,Zhang, Li-Xin,Li, Wen-Jun Springer-Verlag 2010 Antonie van Leeuwenhoek Vol.98 No.1

Induction of Phase I, II and III Drug Metabolism/Transport by Xenobiotics

Xu Chang Jiang,Li Christina YongTao,Kong AhNg Tony The Pharmaceutical Society of Korea 2005 Archives of Pharmacal Research Vol.28 No.3

Drug metabolizing enzymes (DMEs) play central roles in the metabolism, elimination and detoxification of xenobiotics and drugs introduced into the human body. Most of the tissues and organs in our body are well equipped with diverse and various DMEs including phase I, phase II metabolizing enzymes and phase III transporters, which are present in abundance either at the basal unstimulated level, and/or are inducible at elevated level after exposure to xenobiotics. Recently, many important advances have been made in the mechanisms that regulate the expression of these drug metabolism genes. Various nuclear receptors including the aryl hydrocarbon receptor (AhR), orphan nuclear receptors, and nuclear factor-erythoroid 2 p45-related factor 2 (Nrf2) have been shown to be the key mediators of drug-induced changes in phase I, phase II metabolizing enzymes as well as phase III transporters involved in efflux mechanisms. For instance, the expression of CYP1 genes can be induced by AhR, which dimerizes with the AhR nuclear translocator (Arnt) , in response to many polycyclic aromatic hydrocarbon (PAHs). Similarly, the steroid family of orphan nuclear receptors, the constitutive androstane receptor (CAR) and pregnane X receptor (PXR), both heterodimerize with the ret-inoid X receptor (RXR), are shown to transcriptionally activate the promoters of CYP2B and CYP3A gene expression by xenobiotics such as phenobarbital-like compounds (CAR) and dexamethasone and rifampin-type of agents (PXR). The peroxisome proliferator activated receptor (PPAR), which is one of the first characterized members of the nuclear hormone receptor, also dimerizes with RXR and has been shown to be activated by lipid lowering agent fib rate-type of compounds leading to transcriptional activation of the promoters on CYP4A gene. CYP7A was recognized as the first target gene of the liver X receptor (LXR), in which the elimination of cholesterol depends on CYP7A. Farnesoid X receptor (FXR) was identified as a bile acid receptor, and its activation results in the inhibition of hepatic acid biosynthesis and increased transport of bile acids from intestinal lumen to the liver, and CYP7A is one of its target genes. The transcriptional activation by these receptors upon binding to the promoters located at the 5-flanking region of these GYP genes generally leads to the induction of their mRNA gene expression. The physiological and the pharmacological implications of common partner of RXR for CAR, PXR, PPAR, LXR and FXR receptors largely remain unknown and are under intense investigations. For the phase II DMEs, phase II gene inducers such as the phenolic compounds butylated hydroxyanisol (BHA), tert-butylhydroquinone (tBHQ), green tea polyphenol (GTP), (-)-epigallocatechin-3-gallate (EGCG) and the isothiocyanates (PEITC, sul­foraphane) generally appear to be electrophiles. They generally possess electrophilic-medi­ated stress response, resulting in the activation of bZIP transcription factors Nrf2 which dimerizes with Mafs and binds to the antioxidant/electrophile response element (ARE/EpRE) promoter, which is located in many phase II DMEs as well as many cellular defensive enzymes such as heme oxygenase-1 (HO-1), with the subsequent induction of the expression of these genes. Phase III transporters, for example, P-glycoprotein (P-gp), multidrug resistance-associated proteins (MRPs), and organic anion transporting polypeptide 2 (OATP2) are expressed in many tissues such as the liver, intestine, kidney, and brain, and play crucial roles in drug absorption, distribution, and excretion. The orphan nuclear receptors PXR and GAR have been shown to be involved in the regulation of these transporters. Along with phase I and phase II enzyme induction, pretreatment with several kinds of inducers has been shown to alter the expression of phase III transporters, and alter the excretion of xenobiotics, which implies that phase III transporters may also be similarly regulated in a coord

Five novel species of the genus Nocardiopsis isolated from hypersaline soils and emended description of Nocardiopsis salina Li et al. 2004

Li, Wen-Jun,Kroppenstedt, Reiner M.,Wang, Dong,Tang, Shu-Kun,Lee, Jae-Chan,Park, Dong-Jin,Kim, Chang-Jin,Xu, Li-Hua,Jiang, Cheng-Lin Microbiology Society 2006 International journal of systematic and evolutiona Vol.56 No.5

<P>Five novel Nocardiopsis strains isolated from hypersaline soils in China were subjected to a polyphasic analysis to determine their taxonomic position. All of the novel isolates could grow on agar plates at NaCl concentrations of up to 18 % (w/v), with optimum growth at 5-8 %. The DNA G+C contents of the novel strains ranged from 67.9 to 73.2 mol%. The morphological and chemotaxonomic characteristics of the isolates matched those described for members of the genus Nocardiopsis. Based on their 16S rRNA gene sequence analysis, DNA-DNA hybridization values and phenotypic characteristics, including the composition of cell-wall amino acids and sugars, menaquinones, polar lipids and cellular fatty acids, the isolates are proposed as representing five novel species of the genus Nocardiopsis. The novel species are proposed as Nocardiopsis gilva sp. nov. [type strain YIM 90087T (=KCTC 19006T=CCTCC AA 2040012T=DSM 44841T)], Nocardiopsis rosea sp. nov. [type strain YIM 90094T (=KCTC 19007T=CCTCC AA 2040013T=DSM 44842T), Nocardiopsis rhodophaea sp. nov. [type strain YIM 90096T (=KCTC 19049T=CCTCC AA 2040014T=DSM 44843T), Nocardiopsis chromatogenes sp. nov. [type strain YIM 90109T (=KCTC 19008T=CCTCC AA 2040015T=DSM 44844T) and Nocardiopsis baichengensis sp. nov. [type strain YIM 90130T (=KCTC 19009T=CCTCC AA 2040016T=DSM 44845T). On the basis of the chemotaxonomic data, the description of the recently described species Nocardiopsis salina Li et al. 2004 is emended.</P>

Synthesis and Properties of Rod -Coil Triblock Copolymers

Chang Li Xu,고윤수,권용구 한국고분자학회 2007 한국고분자학회 학술대회 연구논문 초록집 Vol.2007 No.4

Safety and antifatigue effect of Korean Red Ginseng: a randomized, double-blind, and placebo-controlled clinical trial

Li Zhang,Xiaoyun Chen,Yanqi Cheng,Qilong Chen,Hongsheng Tan,Dongwook Son,Dongpill Chang,Zhaoxiang Bian,Hong Fang,Hongxi Xu 고려인삼학회 2019 Journal of Ginseng Research Vol.43 No.4

Background: Korean Red Ginseng (KRG) is widely used for strengthening the immune system andfighting fatigue, especially in people with deficiency syndrome. However, there is concern that the longtermapplication or a high dose of KRG can cause “fireness” (上火in Chinese) because of its “dryness” (燥性in Chinese). The aim of this study was to assess the safety and efficacy of a 4-week treatment with KRGin participants with deficiency syndrome. Methods: This was a 4-week, randomized, double-blind, placebo-controlled clinical trial. A total of 180Chinese participants were randomly allocated to three groups: placebo control group, participants weregiven a placebo, 3.6 g/d; KRG 1.8 g and 3.6 g groups. The primary outcomes were the changes in firenessand safety evaluation (adverse events, laboratory tests, and electrocardiogram). The secondary outcomeswere the efficacy of KRG on fatigue, which include the following: traditional Chinese medicine (TCM)symptom scale and fatigue self-assessment scale. Results: Of the 180 patients, 174 completed the full study. After 4 weeks of KRG treatment, the Fire-heatsymptoms score including Excess fire-heat score and Deficient fire-heat score showed no significantchange as compared with placebo treatment, and no clinically significant changes in any safetyparameter were observed. Based on the TCM syndrome score and fatigue self-assessment score, TCMsymptoms and fatigue were greatly improved after treatment with KRG, which showed a dose- and timedependenteffect. The total effective rate was also significantly increased in the KRG groups. Conclusion: Our study revealed that KRG has a potent antifatigue effect without significant adverse effectsin people with deficiency syndrome. Although a larger sample size and longer treatment may berequired for a more definite conclusion, this clinical trial is the first to disprove the common conceptionof “fireness” related to KRG.