• Journal of Power Electronics
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• 제12권5호
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• pp.800-812
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• 2012

This paper analyses the mathematical model and control strategies of a Hybrid Active Power Filter with Injection Circuit (IHAPF). The control strategy based on the load harmonic current detection is selected. A novel control method for a IHAPF, which is based on the analyzed control mathematical model, is proposed. It consists of two closed-control loops. The upper closed-control loop consists of a single fuzzy logic controller and the IHAPF model, while the lower closed-control loop is composed of an Adaptive Network based Fuzzy Inference System (ANFIS) controller, a Neural Generalized Predictive (NGP) regulator and the IHAPF model. The purpose of the lower closed-control loop is to improve the performance of the upper closed-control loop. When compared to other control methods, the simulation and experimental results show that the proposed control method has the advantages of a shorter response time, good online control and very effective harmonics reduction.

• 대한약침학회지
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• 제14권3호
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• pp.5-17
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• 2011

Objectives : Gliosis becomes physical and mechanical barrier to axonal regeneration. Reactive gliosis induced by middle cerebral artery occlusion is involved with up-regulation of CD81 and GFAP (Glial fibrillary acidic protein). The current study is to examine the effect of the Angelica gigas Nakai(intravenous injection. 100 mg/kg twice in a day) on CD81 and GFAP of the rat in the brain after middle cerebral artery occlusion. Methods : Cerebral infarction was induced by middle cerebral artery occlusion. And after intravenous injection of water extract of Angelica gigas Nakai, the size of cerebral infarction was measured. Examination of optical microscope were also used to detect the expression of CD81 and GFAP in the brain of the rat. Results : The following results were obtained : We found that size of cerebral infarcion induced by MCAO (Middle Cerebral Artery Occlusion) in rats were decreased after intravenous injection of Angelica gigas Nakai. We injected the extract of Angelica gigas Nakai to the MCAO in rats, and the optical microscope study showed that Angelica gigas Nakai had effect on protecting the cells of hippocampus. We found that GFAP, CD81 and ERK of the brain in rats with cerebral infarction after MCAO were meaningfully decreased after intravenous injecting Angelica gigas Nakai. We found that c-Fos expression of the brain in rats with cerebral infarction after MCAO were significantly increased after intravenous injecting Angelica gigas Nakai. Conclusions : These results indicate that Angelica gigas Nakai could suppress the reactive gliosis, which disturbs the astrocyte regeneration in the brain of the rat with cerebral infarction after MCAO by controlling the expression of CD81 and GFAP. And the effect may be modulated by the up-regulation of c-Fos and ERK.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.719-723
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• 1998

Prevention of the islanding phenomena is one of the most important issues because it can damage electrical equipment connected to the utility system and endanger human life. It is very difficult to detect an islanding condition of a power distribution line with conventional voltage of frequency relays, while the output power and the load power of utility interactive PV inverter units are in nearly balanced state in both active power and reactive power. This paper describes the protective equipment that prevents the PV system connected to the utility grid from starting islanding. Both predictive ocntrol method and harmonic injection method are used for a current control and islanding detection for operating safety.

• 대한한방내과학회지
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• 제31권4호
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• pp.763-774
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• 2010

Objectives : In condition of brain infarction, irreversible axon damage occurs in central nerve system(CNS), because gliosis becomes physical and mechanical barrier to axonal regeneration. Reactive gliosis induced by ischemic injury such as middle cerebral artery occlusion is involved with up-regulation of GFAP and CD81. The current study is to examine the effect of the Uncariae Ramulus et Uncus on CD81 and GFAP expression in the rat brain following middle cerebral artery occlusion. Methods : In order to study ischemic injuries on brain, infarction was induced by middle cerebral artery occlusion(MCAO) using insertion of a single nylon thread, through the internal carotid artery, into a middle cerebral artery. Cresyl violet staining, cerebral infarction size measurement, immunohistochemistry and microscopic examination were used to detect the expression of CD81 and GFAP and the effect on the infarct size and pyramidal cell death in the brain of the rat with cerebral infarction induced by MCAO. Results : The following results were obtained 1. Measuring the size of cerebral infartion induced by MCAO in the rat after injection of Uncariae Ramulus et Uncus showed the size was decreased. 2. Intravenous injection of Uncariae Ramulus et Uncus showed pyramidal cell death protection in the hippocampus in the MCAO rat. 3. Water extract injection of Uncariae Ramulus et Uncus decreased GFAP expression significantly in the MCAO rat. 4. Uncariae Ramulus et Uncus water extract decreased CD81 expression in the MCAO rat. 5. The administration of water extract of Uncariae Ramulus et Uncus induced up-regulation of c-Fos expression significantly compared with MCAO. 6. The admistration of water extract of Uncariae Ramulus et Uncus increased ERK expression significantly compared with MCAO. Conclusion : We observed that Uncariae Ramulus et Uncus could suppress the reactive gliosis, which disturbs the axonal regeneration in the brain of the rat with cerebral infaction after MCAO by controlling the expression of CD81 and GFAP. The effect may be modulated by the up-regulation of c-Fos and ERK. These results suggest that Uncariae Ramulus et Uncus can be a candidate to regenerate CNS injury.

• BMB Reports
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• 제46권7호
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• pp.370-375
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• 2013

Ischemia is characterized by oxidative stress and changes in the antioxidant defense system. Our recent in vitro study showed that 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride protects cortical astrocytes against oxidative stress. In the current study, we examined the effects of 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride on ischemia-induced neuronal damage in a gerbil ischemia/reperfusion models. Extensive neuronal death in the hippocampal CA1 area was observed 4 days after ischemia/reperfusion. Intraperitoneal injection of 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride (0.3 mg/kg body weight) significantly prevented neuronal death in the CA1 region of the hippocampus in response to transient forebrain ischemia. 2-Cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride administration reduced ischemia-induced increases in reactive oxygen species levels and malondialdehyde content. It also attenuated the associated reductions in glutathione level and superoxide dismutase, catalase, and glutathione peroxidase activities. Taken together, our results suggest that 2-cyclopropylimino-3-methyl-1,3-thiazoline hydrochloride protects against ischemia-induced neuronal damage by reducing oxidative stress through its antioxidant actions.

• Journal of Electrical Engineering and Technology
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• 제11권1호
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• pp.65-75
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• 2016

Aiming at analyzing the power flow of the distribution systems with distribution transformer (DT) branches and PV nodes, a hybrid three-phase power flow methodology is presented in this paper. The incidence formulas among node voltages, loop currents and node current injections have been developed based on node-branch incidence matrix of the distribution network. The method can solve the power flow directly and has higher efficiency. Moreover, the paper provides a modified method to model DT branches by considering winding connections, phase shifting and off-nominal tap ratio, and then DT branches could be seen like one transmission line with the proposed power flow method. To deal with the PV nodes, an improved approach to calculate reactive power increment at each PV node was deduced based on the assumption that the positive-sequence voltage magnitude of PV node is fixed at a given value. Then during calculating the power flow at each iteration, it only needs to update current injection at each PV node with the proposed algorithm. The process is very simple and clear. The results of IEEE 4 nodes and the modified IEEE 34 nodes test feeders verified the correctness and efficiency of the proposed hybrid power flow algorithm.

• Asian Pacific Journal of Cancer Prevention
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• 제15권1호
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• pp.265-271
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• 2014

Interleukin-7 (IL-7) is a potent anti-apoptotic cytokine that enhances immune effector cell functions and is essential for lymphocyte survival. While it known to induce differentiation and proliferation in some haematological malignancies, including certain types of leukaemias and lymphomas, little is known about its role in solid tumours, including breast cancer. In the current study, we investigated whether IL-7 could enhance the in vivo antitumor activity of tumor-reactive $CD8^+$ T cells with induction of IFN-${\gamma}$ in a murine breast cancer model. Human IL-7 cDNA was constructed into the eukaryotic expression plasmid pcDNA3.1, and then the recombinational pcDNA3.1-IL-7 was intratumorally injected in the TM40D BALB/C mouse graft model. Serum and intracellular IFN-${\gamma}$ levels were measured by ELISA and flow cytometry, respectively. $CD8^+$ T cell-mediated cytotoxicity was analyzed using the MTT method. Our results showed that IL-7 administration significantly inhibited tumor growth from day 15 after direct intratumoral injection of pcDNA3.1-IL-7. The anti-tumor effect correlated with a marked increase in the level of IFN-${\gamma}$ and breast cancer cells-specific CTL cytotoxicity. In vitro cytotoxicity assays showed that IL-7-treatment could augment cytolytic activity of $CD8^+$ T cells from tumor bearing mice, while anti-IFN-${\gamma}$ blocked the function of $CD8^+$ T cells, suggesting that IFN-${\gamma}$ mediated the cytolytic activity of $CD8^+$ T cells. Furthermore, in vivo neutralization of $CD8^+$ T lymphocytes by CD8 antibodies reversed the antitumor benefit of IL-7. Thus, we demonstrated that IL-7 exerts anti-tumor activity mainly through activating $CD8^+$ T cells and stimulating them to secrete IFN-${\gamma}$ in a murine breast tumor model. Based on these results, our study points to a potential novel way to treat breast cancer and may have important implications for clinical immunotherapy.