Effects of wind barriers on running safety of trains for urban rail cable-stayed bridge

Wei He,Xiang-Rong Guo,Zhi-hui Zhu,Pengru Deng,Xu-hui He 한국풍공학회 2020 Wind and Structures, An International Journal (WAS Vol.31 No.1

Considering the wind barriers induced aerodynamic characteristic variations of both bridge deck and trains, this paper studies the effects of wind barriers on the safety and stability of trains as they run through an urban rail transit cable-stayed bridge which tends to be more vulnerable to wind due to its relatively low stiffness and lightweight. For the bridge equipped with wind barriers of different characteristics, the aerodynamic coefficients of trains and bridge decks are obtained from wind tunnel test firstly. And then, the space vibration equations of the wind-train-bridge system are established using the experimentally obtained aerodynamic coefficients. Through solving the dynamic equations, one can calculate the dynamic responses both the trains and bridge. The results indicate that setting wind barriers can effectively reduce the dynamic responses of both the trains and bridge, even though more wind forces acting on the bridge are caused by wind barriers. In addition, for urban rail transit cable-stayed bridges located in strong wind environment, the wind barriers are recommended to be set with 20% porosity and 2.5 m height according to the calculation results of cases with wind barriers porosity and height varying in two wide ranges, i.e., 10% - 40% and 2.0 m to 4.0 m, respectively.

Stability investigation of phase disturbances in doubly‑fed wind power systems using phase‑locked synchronization

Wei Chen,Shan He,Jing Cheng,Zhi Yuan,Xueqin Yan 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.2

Under weak grid conditions, there is a strong nonlinear coupling between phase-locked loops (PLLs) and the doubly-fed induction generators (DFIGs), and the influence of its dynamic characteristics on system stability cannot be ignored. For a system to be stable, the dynamic properties must be considered. First, based on instantaneous power theory, the subsynchronous frequency component of power oscillation in a three-phase symmetrical system with the participation of a PLL is deduced. Second, the PLL transient stability is studied under two power grid structures. Third, to connect with the power grid model, a DFIG with a PLL structure is established, and the phase disturbance of the PLL is used as the excitation signal. In the rotor current inner loop and the voltage outer loop transfer processes, the PLL phase disturbance component plays a role. A d-axis structure block diagram of the current loop with the PLL phase disturbance component is constructed, and the disturbance transfer function is deduced. The influence mechanism of the PLL control parameters on system power oscillation is investigated. Finally, the modeling simulation verifies the validity of the theoretical analysis

Preliminary Proteomic Analysis of Thiobacillus ferrooxidans Growing on Elemental Sulphur and Fe(2+) Separately

Zhi Guo He,Yue Hua Hu,Hui Zhong,Wei Xin Hu,Jin Xu 한국생활환경학회 2005 BMB Reports Vol.38 No.3

Resveratrol suppresses the epithelial-to-mesenchymal transition in PC-3 cells by down-regulating the PI3K/AKT signaling pathway

Zhi Wang,Longxiang Wu,Shiyu Tong,Xiheng Hu,Xiongbing Zu,Yuan Li,Wei He,Longfei Liu,Minfeng Chen,Lin Qi 한국통합생물학회 2016 Animal cells and systems Vol.20 No.2

Resveratrol possesses a wide spectrum of pharmacological properties and has been an ideal alternative drug for the treatment of different cancers, including prostate cancer. However, the mechanisms by which resveratrol inhibits the growth of prostate cancer are still not fully elucidated. To understand the effect of resveratrol on the apoptosis and the epithelial-tomesenchymal transition (EMT) of prostate cancer as well as its related mechanism, we investigated the potential use of resveratrol in PC-3 prostate cancer cells in vitro using real-time PCR, fluorescence-activated cell sorting, Western blotting, etc. Resveratrol suppresses the PC-3 prostate cancer cell growth and induces apoptosis. Resveratrol also influences the expression of EMT-related proteins (increased E-cadherin and decreased Vimentin expression). Finally, resveratrol also suppressed Akt phosphorylation in PC-3 cells. This study indicates that resveratrol may be a potential anti-cancer treatment for prostate cancer; moreover, it provides new evidence that resveratrol suppresses prostate cancer growth and metastasis.

Characteristics Comparison before and after Lyophilization of Transferrin Modified Procationic-Liposome-Protamine-DNA Complexes (Tf-PLPD)

Zhi-Rong Zhong,Zhi-rong Zhang,Ji Liu,Yong Deng,Hong-wei Zhang,Yao Fu,Qing-guo Song,Qin He 대한약학회 2007 Archives of Pharmacal Research Vol.30 No.1

A novel non-viral gene delivery system, Procationic-Liposome-Protamine-DNA complexes (PLPD) which could further adsorb transferrin on the surface as a targeting ligand to form Tf- PLPD, was prepared and characterized before and after lyophilization. The size distribution of Tf-PLPD was in the range of 240 ± 12 nm and the zeta potential was -24.10 ± 2.5 mV. The transfection efficiencies of PLPD and Tf-PLPD were 12.18 ± 3.8 and 24.26 ± 2.6 mU β-galactosidase/ mg protein respectively. The lyophilization and the presence of serum didn’t affect the tansfectivities of PLPD or Tf-PLPD. Compared to LipofectamineTM 2000 (Invitrogen, U.S.A.), the procationic liposomes had less cytotoxicity to cells. In summary the procationic lipoplex described here, combining the condensing effect of protamine and the targeting capability of Tf, was a perspective non-viral vector for gene delivery system.

Preliminary Proteomic Analysis of Thiobacillus ferrooxidans Growing on Elemental Sulphur and Fe²⁺ Separately

He, Zhi-guo,Hu, Yue-Hua,Zhong, Hui,Hu, Wei-Xin,Xu, Jin Korean Society for Biochemistry and Molecular Biol 2005 Journal of biochemistry and molecular biology Vol.38 No.3

Thiobacillus ferrooxidans is one of the most important bacterium used in bioleaching, and can utilize $Fe^{2+}$ or sulphide as energy source. Growth curves for Thiobacillus ferrooxidans have been tested, which show lag, logarithmic, stationary and aging phases as seen in other bacteria. The logarithmic phases were from 10 to 32 hours for Thiobacillus ferrooxidans cultivated with $Fe^{2+}$ and from 4 to 12 days for Thiobacillus ferrooxidans cultivated with elemental sulphur. Differences of protein patterns of Thiobacillus ferrooxidans growing on elemental sulphur and $Fe^{2+}$ separately were investigated after cultivation at $30^{\circ}C$ by the analysis of two-dimensional gel electrophoresis (2-DE), matrix-assisted laser desorption/ ionization (MALDI)-Mass spectrometry and ESI-MS/MS. From the 7 identified protein spots, 11 spots were found more abundant when growing on elemental sulphur. By contrast 6 protein spots were found decreased at elemental cultivation condition. Among the proteins identified, cytochrome C have been previously identified as necessary elements of electron-transfering pathway for Thiobacillus ferrooxidans to oxidize $Fe^{2+}$; ATP synthase alpha chain and beta are expressed increased when Thiobacillus ferrooxidans cultivated with $Fe^{2+}$ as energy source. ATP synthase Beta chain is the catalytic subunit, and ATP synthase alpha chain is a regulatory subunit. The function of ATPase produces ATP from ADP in the presence of a proton gradient across the membrane.

Development of a High-Speed and Precision Micro- Spindle for Micro-Cutting

Wei Liu,Zhixiong Zhou,Xiangming Huang,Zhi-Jian He,Yong Du 한국정밀공학회 2014 International Journal of Precision Engineering and Vol. No.

Mechanical micromachining using micro-machine tools is very competitive in manufacturing geometrically complex 3D micro-partsin various engineering materials with advantages of small space, energy-efficient, low equipment production and operation costs. Askey components of micro-machine tools, micro-spindles directly determine the performance of micro-machine tools and theapplication and development of mechanical micromachining technology. This study proposes a novel design concept of the separatelyspindle and tool and one-piece tool/rotor structure for micro-spindles, whose micro-tool can maintain good rotational accuracy athigh rotational speeds. In the principle prototype micro-spindle, an air driven turbine was used as power spindle. The design andoptimization of the micro-spindle were conducted. The fabrication and evaluation of the prototype micro-spindle were presented. Theresults of the principle prototype micro-spindle were analyzed and some efforts for the subsequent micro-spindle were proposed.

ZD1839 and Cisplatin Alone or in Combination for Treatment of a Nasopharyngeal Carcinoma Cell Line and Xenografts

Gu, Wei-Guang,Huang, Yan,Yuan, Zhong-Yu,Peng, Rou-Jun,Luo, Hai-Tao,He, Zhi-Ren,Wang, Shu-Sen Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.3

This study evaluated the effects of ZD1839, an orally active, selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, on nasopharyngeal carcinoma (NPC) both in vitro and in vivo. Influence of ZD1839 alone or combined with cisplatin on the NPC cell line CNE2 was detected by MTT assay with flow cytometry assessment of cell cycle distribution and apoptosis rates. Nude mice NPC xenografts were also used to evaluate the effects of ZD1839 alone or combined with cisplatin. The Student's t test evaluated statistical significance. ZD1839 alone or combined with cisplatin inhibited CNE2 cell line proliferation. ZD1839 induced CNE2 cell cycle arrest in the G1 phase, and higher concentrations induced apoptosis. Xenograft tumors were significantly smaller when treated with 200 mg/kg ZD1839, cisplatin, or cisplatin combined with 100 mg/kg ZD1839 than untreated controls. ZD1839 (200 mg/kg) alone showed good tumor inhibition effects, reduction of tumor weights, and smaller tumor volume without loss of body weight. ZD1839 (200 mg/kg) might provide a good and effective therapeutic reagent for NPC.

Loss of MicroRNA-137 Impairs the Homeostasis of Potassium in Neurons via KCC2

Ting-Wei Mi,Xiao-Wen Sun,Zhi-Meng Wang,Ying-Ying Wang,Xuan-Cheng He,Cong Liu,Shuang-Feng Zhang,Hong-Zhen Du,Chang-Mei Liu,Zhao-Qian Teng 한국뇌신경과학회 2020 Experimental Neurobiology Vol.29 No.2

Neuropsychiatric disorders are the leading cause of mental and intellectual disabilities worldwide. Current therapies against neuropsychiatric disorders are very limited, and very little is known about the onset and development of these diseases, and their most effective treatments. MIR137 has been previously identified as a risk gene for the etiology of schizophrenia, bipolar disorder, and autism spectrum disorder. Here we generated a forebrain-specific MIR137 knockout mouse model, and provided evidence that loss of miR-137 resulted in impaired homeostasis of potassium in mouse hippocampal neurons. KCC2, a potassium-chloride co-transporter, was a direct downstream target of miR-137. The KCC2 specific antagonist VU0240551 could balance the current of potassium in miR-137 knockout neurons, and knockdown of KCC2 could ameliorate anxiety-like behavior in MIR137 cKO mice. These data suggest that KCC2 antagonists or knockdown might be beneficial to neuropsychiatric disorders due to the deficiency of miR-137.

Anti-proliferative Effects of Atractylis lancea (Thunb.) DC. via Down-regulation of the c-myc/hTERT/Telomerase Pathway in Hep-G2 Cells

Guo, Wei-Qiang,Li, Liang-Zhi,He, Zhuo-Yang,Zhang, Qi,Liu, Jia,Hu, Cui-Ying,Qin, Fen-Ju,Wang, Tao-Yun Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

Atractylis lancea (Thunb.) DC. (AL), an important medicinal herb in Asia, has been shown to have anti-tumor effects on cancer cells, but the involved mechanisms are poorly understood. This study focused on potential effects and molecular mechanisms of AL on the proliferation of the Hep-G2 liver cancer cell line in vitro. Cell viability was assessed by MTT test in Hep-G2 cells incubated with an ethanol extract of AL. Then, the effects of AL on apoptosis and cell cycle progression were determined by flow cytometry. Telomeric repeat amplification protocol (TRAP) assays was performed to investigate telomerase activity. The mRNA and protein expression of human telomerase reverse transcriptase (hTERT) and c-myc were determined by real-time RT-PCR and Western blotting. Our results show that AL effectively inhibits proliferation in Hep-G2 cells in a concentrationand time-dependent manner. When Hep-G2 cells were treated with AL after 48h,the $IC_{50}$ was about 72.1 ${\mu}g/mL$. Apoptosis was induced by AL via arresting the cells in the G1 phase. Furthermore, AL effectively reduced telomerase activity through inhibition of mRNA and protein expression of hTERT and c-myc. Hence, these data demonstrate that AL exerts anti-proliferative effects in Hep-G2 cells via down-regulation of the c-myc/hTERT/telomerase pathway.