Calculation of Magnetic Field for Cylindrical Stator Coils in Permanent Magnet Spherical Motor

Li, Hongfeng,Ma, Zigang,Han, Bing,Li, Bin,Li, Guidan The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.6

This paper analyzed the magnetic field produced by the cylindrical stator coils of permanent magnet spherical motor (PMSM). The elliptic equations about the vector magnetic potential were given. Given that the eddy current effects are neglected, the magnet field of the PMSM is regarded as irrotational field, which can be calculated by scalar magnetic potential. The current density of cylindrical stator coil was proposed based on the definition of current density. The expression of current density of stator coil was obtained according to the double Fourier series decomposition and spherical harmonic functions. Then the magnetic flux density for scalar magnetic potential was derived. Further, the influence of different parameters on radial flux density was also analyzed. Finally, the results by the analytical method in this paper were validated by finite element analysis (FEA).

Calculation of Magnetic Field for Cylindrical Stator Coils in Permanent Magnet Spherical Motor

Hongfeng Li,Zigang Ma,Bing Han,Bin Li,Guidan Li 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.6

This paper analyzed the magnetic field produced by the cylindrical stator coils of permanent magnet spherical motor (PMSM). The elliptic equations about the vector magnetic potential were given. Given that the eddy current effects are neglected, the magnet field of the PMSM is regarded as irrotational field, which can be calculated by scalar magnetic potential. The current density of cylindrical stator coil was proposed based on the definition of current density. The expression of current density of stator coil was obtained according to the double Fourier series decomposition and spherical harmonic functions. Then the magnetic flux density for scalar magnetic potential was derived. Further, the influence of different parameters on radial flux density was also analyzed. Finally, the results by the analytical method in this paper were validated by finite element analysis (FEA).

Aloe-emodin suppresses prostate cancer by targeting the mTOR complex 2.

Liu, Kangdong,Park, Chanmi,Li, Shengqing,Lee, Ki Won,Liu, Haidan,He, Long,Soung, Nak Kyun,Ahn, Jong Seog,Bode, Ann M,Dong, Ziming,Kim, Bo Yeon,Dong, Zigang IRL Press] ; Oxford University Press 2012 Carcinogenesis Vol.33 No.7

<P>Phosphatidylinositol 3-kinase (PI3-K) amplification and phosphatase and tensin homolog (PTEN) deletion-caused Akt activation contribute to the development of prostate cancer. Mammalian target of rapamycin complex 2 (mTORC2) is a kinase complex comprised of mTOR, Rictor, mSin1, mLST8/G관L and PRR5 and functions in the phosphorylation of Akt at Ser473. Herein, we report that mTORC2 plays an important role in PC3 androgen refractory prostate cell proliferation and anchorage-independent growth. Aloe-emodin, a natural compound found in aloe, inhibited both proliferation and anchorage-independent growth of PC3 cells. Protein content analysis suggested that activation of the downstream substrates of mTORC2, Akt and PKC관, was inhibited by aloe-emodin treatment. Pull-down assay and in vitro kinase assay results indicated that aloe-emodin could bind with mTORC2 in cells and inhibit its kinase activity. Aloe-emodin also exhibited tumor suppression effects in vivo in an athymic nude mouse model. Collectively, our data suggest that mTORC2 plays an important role in prostate cancer development and aloe-emodin suppresses prostate cancer progression by targeting mTORC2.</P>

Uniform DNA Biosensors Based on Threshold Voltage of Carbon Nanotube Thin-Film Transistors

Yanyan Deng,Fang Yuan,Min ZHANG,Zigang Li,Wenyu Zhou 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2016 NANO Vol.11 No.5

Uniformity is a key parameter to assure the accuracy of biosensor devices. In this work, highly uniform carbon nanotube thin-film transistors (CNT-TFTs) with a standard deviation of threshold voltage (Vth) as small as 0.04 were achieved by accurately controlling the fabrication process, which is so far the most stable distribution to our knowledge. On-state current (Ion), off-state current and on/off current ratio also exhibit high uniformity with low standard deviation of 0.50, 0.72 and 0.54, respectively. Given the high uniformity, high stability and high sensitivity, the CNT-TFTs are used as ultra-sensitive 5-hydroxymethyl cytosine (5-hmC) detecting devices for the first time, which is one of the important modified bases in DNA and plays an important role in epigenetics. After attachment of 5-hmC DNA, a reproducible and stable shift of 18.7–59% in Vth as well as a 31–54% change in Ion were observed in the transfer characteristics curves of CNT-TFTs. Thus, a detecting device of 5-hmC in DNA segments could be designed based on the highly uniform CNT-TFTs.

Licochalcone A, a Natural Inhibitor of c-Jun <i>N</i>-Terminal Kinase 1

Yao, Ke,Chen, Hanyong,Lee, Mee-Hyun,Li, Haitao,Ma, Weiya,Peng, Cong,Song, Nu Ry,Lee, Ki Won,Bode, Ann M.,Dong, Ziming,Dong, Zigang American Association for Cancer Research 2014 Cancer Prevention Research Vol.7 No.1

<P>The c-<I>Jun N</I>-terminal kinases (JNK) play an important role in many physiologic processes induced by numerous stress signals. Each JNK protein appears to have a distinct function in cancer, diabetes, or Parkinson's disease. Herein, we found that licochalcone A, a major phenolic constituent isolated from licorice root, suppressed JNK1 activity but had little effect on JNK2 <I>in vitro</I> activity. Although licochalcone A binds with JIP1 competitively with either JNK1 or JNK2, a computer simulation model showed that after licochalcone A binding, the ATP-binding cleft of JNK1 was distorted more substantially than that of JNK2. This could reduce the affinity of JNK1 more than JNK2 for ATP binding. Furthermore, licochalcone A inhibited JNK1-mediated, but not JNK2-mediated, c-Jun phosphorylation in both <I>ex vivo</I> and <I>in vitro</I> systems. We also observed that in colon and pancreatic cancer cell lines, JNK1 is highly expressed compared with normal cell lines. In cancer cell lines, treatment with licochalcone A or knocking down JNK1 expression suppressed colon and pancreatic cancer cell proliferation and colony formation. The inhibition resulted in G<SUB>1</SUB> phase arrest and apoptosis. Moreover, an <I>in vivo</I> xenograft mouse study showed that licochalcone A treatment effectively suppressed the growth of HCT116 xenografts, without affecting the body weight of mice. These results show that licochalcone A is a selective JNK1 inhibitor. Therefore, we suggest that because of the critical role of JNK1 in colon cancer and pancreatic carcinogenesis, licochalcone A might have preventive or therapeutic potential against these devastating diseases. <I>Cancer Prev Res; 7(1); 139–49. ©2013 AACR</I>.</P>

Role of Functionalized Acceptors in Heteroleptic Bipyridyl Cu(I) Complexes for Dye-Sensitized Solar Cells

Xiaoqing Lu,Yang Shao,Ke Li,Zigang Zhao,Shuxian Wei,Wenyue Guo 대한금속·재료학회 2016 ELECTRONIC MATERIALS LETTERS Vol.12 No.5

The intrinsic optoelectronic properties of heteroleptic bipyridyl Cu(I)complexes bearing functionalized acceptor subunits have beeninvestigated by density functional theory and time-dependent DFT. TheCu(I) complexes exhibit distorted trigonal-pyramidal geometries andtypical metal-to-ligand electron transfer characteristics at the longwavelength region. Replacing carboxylic acid with cyanoacrylic acid inacceptor subunits stabilizes the LUMO levels, thus lowering the HOMOLUMOenergy gaps and facilitating favorable donor-to-acceptorintramolecular electron transfer and charge separation. Introduction ofheteroaromatic groups and cyanoacrylic acid significantly improves thelight-harvesting capability of the complexes. Our results highlight theeffect of functionalized acceptors on the optoelectronic properties ofbipyridyl Cu(I) complexes and provide a fresh perspective on screeningof efficient sensitizers for dye-sensitized solar cells.

[6]-Gingerol Suppresses Colon Cancer Growth by Targeting Leukotriene A₄ Hydrolase

Jeong, Chul-Ho,Bode, Ann M.,Pugliese, Angelo,Cho, Yong-Yeon,Kim, Hong-Gyum,Shim, Jung-Hyun,Jeon, Young-Jin,Li, Honglin,Jiang, Hualiang,Dong, Zigang American Association for Cancer Research 2009 Cancer Research Vol.69 No.13

<P>[6]-Gingerol, a natural component of ginger, exhibits anti-inflammatory and antitumorigenic activities. Despite its potential efficacy in cancer, the mechanism by which [6]-gingerol exerts its chemopreventive effects remains elusive. The leukotriene A(4) hydrolase (LTA(4)H) protein is regarded as a relevant target for cancer therapy. Our in silico prediction using a reverse-docking approach revealed that LTA(4)H might be a potential target of [6]-gingerol. We supported our prediction by showing that [6]-gingerol suppresses anchorage-independent cancer cell growth by inhibiting LTA(4)H activity in HCT116 colorectal cancer cells. We showed that [6]-gingerol effectively suppressed tumor growth in vivo in nude mice, an effect that was mediated by inhibition of LTA(4)H activity. Collectively, these findings indicate a crucial role of LTA(4)H in cancer and also support the anticancer efficacy of [6]-gingerol targeting of LTA(4)H for the prevention of colorectal cancer.</P>