Modelling and Experimental Study of Halbach Array Magnetic Coupler

De-yong Li,Shuang Wang,Yongcun Guo,Xin Ma 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.1

In order to effectively solve the current problems of magnetic couplers such as large area and complex internal coil, the Halbach array magnetic coupler was proposed. According to the specific characteristics of the hybrid magnetic coupler structure, the mathematical model of air gap magnetic flux density is established by using the combination of electric circuit and electromagnetic field solution. Based on the current superposition, the current is converted to the surface of the copper conductor, and the electromagnetic torque model of the space magnetic field is established by integrating the induced electromotive force along the circumferential direction. In order to verify the correctness of theoretical analysis, the 1:4 prototype was designed and manufactured. Then simulation verification and experiment measurement on its mechanical behaviour are performed. The results show that the maximum error of theoretical value, simulation value and test value is 9.3%. Under the same volume size, the output torque of Halbach array magnetic coupler is increased by 16.1% compared with the ordinary disk magnetic coupler. The research could provide the reference for the design and experimental research of magnetic coupler.

Experimental study on axial compressive behavior of hybrid FRP confined concrete columns

Li-Juan Li,Lan Zeng,Shun-De Xu,Yong-Chang Guo 사단법인 한국계산역학회 2017 Computers and Concrete, An International Journal Vol.19 No.4

In this paper, the mechanical property of CFRP, BFRP, GFRP and their hybrid FRP was experimentally studied. The elastic modulus and tensile strength of CFRP, BFRP, GFRP and their hybrid FRP were tested. The experimental results showed that the elastic modulus of hybrid FRP agreed well with the theoretical rule of mixture, which means the property of hybrid composites are linear with the volumes of the corresponding components while the tensile strength did not. The bearing capacity, peak strain, stress-strain relationship of circular concrete columns confined by CFRP, BFRP, GFRP and hybrid FRP subjected to axial compression were recorded. And the confinement effect of hybrid FRP on concrete columns was analyzed. The test results showed that the bearing capacity and ductility of concrete columns were efficiently improved through hybrid FRP confinement. A strength model and a stress-strain relationship model of hybrid FRP confined concrete columns were proposed. The proposed stress-strain model was shown to be capable of providing accurate prediction of the axial compressive strength of hybrid FRP confined concrete compared with Teng et al. (2002) model, Karbhari and Gao (1997) model and Miyachi et al. (1999) model. The modified stress-strain model was also suitable for single FRP confinement cases and it was so concise in form and didn't have piecewise fitting, which would be easy for use in structural design.

Enhancement of Wear Resistance of CoCrNiAlTi Plasma Sprayed Coatings Using Titanium Carbide

De-Yong Li,이철희 한국트라이볼로지학회 2023 한국트라이볼로지학회지 (Tribol. Lubr.) Vol.39 No.1

Large drill bits may face high hardness ore and high working pressure when working. To optimize the use effect of large drill bits and prolong the use time, it is necessary to add a layer of pressure-resistant, wear-resistant, and low-friction coating on the surface of the drill bit. In this study, CoCrNiAlTi high-entropy alloy coatings and CoCrNiAlTi (70 wt%)-TiC (30 wt%) composite coatings are successfully prepared on Q235 steel by plasma spraying. The CoCrNiAlTi (70 wt%)-TiC (30 wt%) coating consists of FCC solid solution and a small amount of TiC phase. The effect of TiC on the composition phase, microhardness, and elastic modulus of HEA coating is studied by X-ray diffractometer (XRD) and microhardness tester. The effect of TiC on the friction and wear properties of HEA coatings is investigated using a wear tester. By improving the process parameters, the metallurgical bonding between the coating and the substrate is well combined, and a coating without pores and cracks is obtained. The experimental results confirm that the microhardness, elastic modulus, and wear resistance of CoCrNiAlTi-TiC composite coating are better, and the friction coefficient is lower.

Identification of Specific Gene Modules in Mouse Lung Tissue Exposed to Cigarette Smoke

Xing, Yong-Hua,Zhang, Jun-Ling,Lu, Lu,Li, De-Guan,Wang, Yue-Ying,Huang, Song,Li, Cheng-Cheng,Zhang, Zhu-Bo,Li, Jian-Guo,Xu, Guo-Shun,Meng, Ai-Min Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.10

Background: Exposure to cigarette may affect human health and increase risk of a wide range of diseases including pulmonary diseases, such as chronic obstructive pulmonary disease (COPD), asthma, lung fibrosis and lung cancer. However, the molecular mechanisms of pathogenesis induced by cigarettes still remain obscure even with extensive studies. With systemic view, we attempted to identify the specific gene modules that might relate to injury caused by cigarette smoke and identify hub genes for potential therapeutic targets or biomarkers from specific gene modules. Materials and Methods: The dataset GSE18344 was downloaded from the Gene Expression Omnibus (GEO) and divided into mouse cigarette smoke exposure and control groups. Subsequently, weighted gene co-expression network analysis (WGCNA) was used to construct a gene co-expression network for each group and detected specific gene modules of cigarette smoke exposure by comparison. Results: A total of ten specific gene modules were identified only in the cigarette smoke exposure group but not in the control group. Seven hub genes were identified as well, including Fip1l1, Anp32a, Acsl4, Evl, Sdc1, Arap3 and Cd52. Conclusions: Specific gene modules may provide better understanding of molecular mechanisms, and hub genes are potential candidates of therapeutic targets that may possible improve development of novel treatment approaches.

Tumor Inhibition Effects and Mechanisms of Angelica sinensis and Sophorae flavescentis ait Decoction Combined with Cisplatin in Xenograft Mice

Yan, De-Qi,Liu, Yong-Qi,Li, Ying-Dong,Li, Dou,Cheng, Xiao-Li,Wu, Zhi-Wei Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.11

Background: To investigate tumor inhibition effects and mechanisms of Angelica sinensis and Sophorae flavescentis ait decoction (ASSF) combined with diamine-dichloroplatinum (DDP). Materials and Methods: Bodyweight, tumor inhibition rate and q value were calculated for single ASSF or ASSF combined with DDP on H22 carcinoma xenograft KM mice. Biochemical methods for serum LDH, AST, ALT, and AKP, ELISA method for serum HIF-$1{\alpha}$, pathological assessemnt of thymus, immunohistochemistry detection of tumor tissue caspase3 and mutant p53 protein, and qRT-PCR detection of bax/ bcl-2 mRNA were applied. Results: Compared with DDP control group, the bodyweight increased in ASSF-DDP group (p<0.01). Tumor inhibition rates for DDP, ASSF, ASSF-DDP were 62.7%. 43.7% and 71.0% respectively, with a q value of 0.90. Compared with other groups, thymus of DDP control group had obvious pathological injury (p<0.01), serum LDH, AST, ALT, AKP increased significantly in DDP control group (p<0.01), while serum HIF-$1{\alpha}$ was increased in the model control group. Compared with this latter, the expression of mutant p53 protein and bcl-2 mRNA were decreased in all treatment groups (p<0.01), but there were no statistical difference between DDP control p and ASSF-DDP groups. The expression of caspase3 protein and bax mRNA was increased in all treatment groups, with statistical differences between the DDP and ASSF-DDP groups (p<0.01). Conclusions: ASSF can inhibit bodyweight decrease caused by DDP, can inhibit tumor growth synergistically with DDP mainly through increasing serum HIF-$1{\alpha}$ and pro-apoptotic molecules such as caspase 3 and bax, rather than through decreasing anti-apoptotic mutant p53 and bcl-2. ASSF can reduce DDP toxicity due to decreasing the release of LDH, AST, ALT, AKP into blood and enhancing thymus protection.

Attenuation of Experimental Autoimmune Hepatitis in Mice with Bone Mesenchymal Stem Cell-Derived Exosomes Carrying MicroRNA-223-3p

Yong-Ping Chen,Feng-Bin Lu,Da-Zhi Chen,Lu Chen,En-De Hu,Jin-Lu Wu,Hui Li,Yue-Wen Gong,Zhuo Lin,Xiao-Dong Wang,Ji Li,Xiao-Ya Jin,Lan-Man Xu 한국분자세포생물학회 2019 Molecules and cells Vol.42 No.12

MicroRNA-223-3p (miR-223-3p) is one of the potential microRNAs that have been shown to alleviate inflammatory responses in pre-clinical investigations and is highly encased in exosomes derived from bone mesenchymal stem cells (MSC-exosomes). MSC-exosomes are able to function as carriers to deliver microRNAs into cells. Autoimmune hepatitis is one of the challenging liver diseases with no effective treatment other than steroid hormones. Here, we examined whether MSC-exosomes can transfer miR-223-3p to treat autoimmune hepatitis in an experimental model. We found that MSC-exosomes were successfully incorporated with miR-223-3p and delivered miR-223-3p into macrophages. Moreover, there was no toxic effect of exosomes on the macrophages. Furthermore, treatments of either exosomes or exosomes with miR-223-3p successfully attenuated inflammatory responses in the liver of autoimmune hepatitis and inflammatory cytokine release in both the liver and macrophages. The mechanism may be related to the regulation of miR-223-3p level and STAT3 expression in the liver and macrophages. These results suggest that MSC-exosomes can be used to deliver miR-223-3p for the treatment of autoimmune hepatitis.

FK-3000 isolated from <i>Stephania delavayi</i> Diels. inhibits MDA-MB-231 cell proliferation by decreasing NF-κB phosphorylation and COX-2 expression

DE XU, HONG,CHO, SOON-CHANG,BANG, MI-AE,BAE, CHUN-SIK,CHOI, YEONSHIK,LI, YONG-CHUN,LIM, SEUNG-KIL,SHIM, JAEGAL,PARK, DAE-HUN D.A. Spandidos 2015 International journal of oncology Vol.46 No.6

<P>The World Health Organization (WHO) has reported that cancer is one of the most prevalent diseases and a leading cause of death worldwide. Many anticancer drug development studies have been pursued over the last few decades and several viable drugs have been discovered, such as paclitaxel, topotecan and irinotecan. Previously, our research group uncovered the cytocidal and cytostatic effects of the plant <I>Stephania delavayi</I> Diels. In this study, we determined the active chemical to be 6,7-di-O-acetylsinococuline (FK-3000). The FK-3000 half maximal inhibitory concentration (IC<SUB>50</SUB>) in MDA-MB-231 breast carcinoma cells at 48 h was 0.52 μg/ml and it induced apoptosis in a dose- and time-dependent manner. FK-3000 suppressed NF-κB nuclear translocation, decreased NF-κB phosphorylation, and decreased COX-2 protein expression. MDA-MB-231 xenografted mice were treated with FK-3000, Taxol, or their combination for 21 days. The tumor size was smallest in the co-treatment group, indicating that FK-3000 may have a synergistic effect with Taxol. FK-3000 treatment showed no adverse effects on blood cell counts, serum protein levels, or pathology. These studies demonstrate that FK-3000, isolated from <I>S. delavayi</I> Diels., is a promising, pathway-specific anticancer agent that exhibits low toxicity.</P>

ISPD Peritonitis Recommendations: 2016 Update on Prevention and Treatment

Li, Philip Kam-Tao,Szeto, Cheuk Chun,Piraino, Beth,de Arteaga, Javier,Fan, Stanley,Figueiredo, Ana E.,Fish, Douglas N.,Goffin, Eric,Kim, Yong-Lim,Salzer, William,Struijk, Dirk G.,Teitelbaum, Isaac,Joh Multimed Inc 2016 Peritoneal dialysis international Vol.36 No.5

Elevated Platelets Enhance Cancer Cell Migration, Promote Hematogenous Metastasis and Associate with a Poor Prognosis in Advanced Non-small Cell Lung Cancer Cases

Li, Yan,Miao, Li-Yun,Xiao, Yong-Long,Cai, Hou-Rong,Zhang, De-Ping Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.1

Although correlations between platelets and lung cancer has been recognized, effects on non-small cell lung cancer (NSCLC) metastasis remain to be determined in detail. In the present study, wound healing assays revealed a role of platelets in NSCLC cell migration. Thus the mean migration rate of lung adenocarcinoma A549 cells was significantly elevated after co-culture with platelets ($81.7{\pm}0.45%$ vs $41.0{\pm}3.50%$, P<0.01). Expression of GAPDH was examined by reverse transcription-polymerase chain reaction to study the effect of platelets on NSCLC cell proliferation. The result showed that the proliferation of A549 and SPC-A1 cells was not affected. Mouse models were established by transfusing A549 cells and SPC-A1 cells into mice lateral tail veins. We found tumor metastasis nodules in lungs to be increased significantly after co-transfusion with platelets (in A549, $4.33{\pm}0.33$ vs $0.33{\pm}0.33$, P=0.01; in SPC-A1, $2.67{\pm}0.33$ vs $0.00{\pm}0.00$, P=0.01). In addition, consecutive inoperable patients with newly diagnosed NSCLC (TNM stage III or IV) between January 2009 and December 2011 were retrospectively reviewed. Using the Kaplan-Meier method, NSCLC patients with a high platelet counts demonstrated a significantly shorter progression free survival compared with those with a low platelet count (> $200{\times}10^9/L$, 3 months versus ${\leq}200{\times}10^9/L$, 5 months, P=0.001). An elevated platelet count was also identified as an independent prognostic factor by Cox regression analysis for prgression free survival (adjusted hazard ratio: 1.69; 95% CI: 1.16, 2.46; P=0.006). This study suggested that platelets might contribute to the hematogenous metastatic process by promoting cancer cell migration, which eventually affects the prognosis of NSCLC.

일문전(Stephania delavayi Diels.) 메탄올, 부탄올, 에틸아세테이트 분획물의 항산화 및 세포증식억제 효과

이용순(Yong-Chun Li),김경희(Kyoung-Hee Kim),서홍덕(Hong-De Xu),박대훈(Dae-Hun Park),최연식(Yeon Shik Choi),황혜림(Hye-Rim Hwang),이민재(Min-Jae Lee),최종진(Jong-Jin Choi),권명상(Myung-Sang Kwon),육홍선(Hong-Sun Yook) 한국식품영양과학회 2009 한국식품영양과학회지 Vol.38 No.3

본 연구에서는 중국에서 급성 위장염에 대한 약제로 사용되어 오던 일문전의 메탄올 추출물을 이용하여 물, 에틸 아세테이트, 부탄올 층으로 분획한 뒤 항산화 활성과 항암활성을 측정하였다. DPPH 라디칼 소거능은 1,000 ㎍/mL 농도에서 부탄올(75.23%)>메탄올(68.11%)>에틸아세테이(63.58%)>물(50.13%) 순으로 나타났으며 환원력의 경우 용매 분획물의 농도가 증가함에 따라 환원력이 증가하는 경향을 나타내었다. DPPH 라디칼 소거능 및 환원력 모두 부탄올 분획층에서 좋은 활성을 나타내었다. 항암활성 측정결과 메탄올 추출물과 부탄올 분획물, 에틸 아세테이트 분획물에서 MDA-MB-231 cell과 MCF-7 cell에 대한 세포증식억제효과를 나타내었다. 이상의 결과에서 일문전의 용매 분획물은 항암 후보물질로의 가능성이 있을 것으로 사료된다. Stephania delavayi Diels. (S. delavayi Diels.) has been used as a drug for pain-relieving and acute gastroenteritis treatment in China. Because the major therapeutic mechanism of anti-inflammatory drug is to inhibit the cyclooxygenase (COX)-2 and because COX-2 proteins inhibit apoptosis, COX-2 inhibitor has been thought as the anticancer drug candidate. For this reason, we examined S. delavayi Diels. as an anticancer drug. S. delavayi Diels. was fractionated with methanol and then partitioned with ethyl acetate, n-butanol and water. The antioxidant activity was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and reducing power. DPPH radical scavenging activities of the crude fractions at the concentration of 1,000 ㎍/mL were 75.23% (n-butanol), 68.11% (methanol), 63.58% (ethyl acetate), and 50.13% (water). The reducing power increased according to the concentration in dose-dependent manner. Also, when the antiproliferation effects of each fraction against human breast cancer cell-lines MDA-MB-231 and MCF-7 were examined, methanol extract, n-butanol fraction and ethyl acetate fraction exhibited cell proliferative inhibition effects in both cell-lines whereas water fraction did not. Among the crude fractions, the n-butanol fraction exhibited the most potent anti-proliferation effect. In conclusion, fractions from S. delavayi Diels. are promising anticancer drug candidates.