• ETRI Journal
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• v.27 no.5
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• pp.473-483
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• 2005

In this paper, we propose two LC voltage-controlled oscillators (VCOs) that improve both phase noise and tuning range. With both 1/f induced low-frequency noise and low-frequency thermal noise around DC or around harmonics suppressed significantly by the employment of a current-current negative feedback (CCNF) loop, the phase noise in the CCNF LC VCO has been improved by about 10 dB at 6 MHz offset compared to the conventional LC VCO. The phase noise of the CCNF VCO was measured as -112 dBc/Hz at 6 MHz offset from 5.5 GHz carrier frequency. Also, we present a bandwidth-enhanced LC VCO whose tuning range has been increased about 250 % by connecting the varactor to the bases of the cross-coupled pair. The phase noise of the bandwidth-enhanced LC-tank VCO has been improved by about 6 dB at 6 MHz offset compared to the conventional LC VCO. The phase noise reduction has been achieved because the DC-decoupling capacitor Cc prevents the output common-mode level from modulating the varactor bias point, and the signal power increases in the LC-tank resonator. The bandwidth-enhanced LC VCO represents a 12 % bandwidth and phase noise of -108 dBc/Hz at 6 MHz offset.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.6
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• pp.809-817
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• 2013

The aim of this study was to evaluate the mechanism of vasodilation of Lespedezea cuneata(LC) in rabbit common carotid artery and cavernosal smooth muscle. LC relaxed arterial strips precontracted with norepinephrine and cavernosal strips precontracted with phenylephrine. The arterial relaxation effects of LC was endothelium-dependent. $N{\omega}$-nitro-L-arginine(L-NNA), NOS inhibitor, methylene blue(MB), cGMP inhibitor, indomethacin(IM), cyclo-oxygenase inhibitor and tetraethylammonium chloride(TEA), KCa-channel blocker attenuate the relaxation responses of LC in arterial strips. In $Ca^{2+}$-free krebs-ringer solution, pretreatment of LC extract significantly reduced the contraction induced by addition $Ca^{2+}$. L-NNA reduced LC extract-induced relaxation in cavernosal strips, but IM, TEA and MB didn't affect LC extract-induced relaxation. When LC extract was applicated on human umbilical vein endothelial cell, the nitric oxide concentration was increased. We conclude that in rabbit common carotid artery, LC may suppress influx of extra-cellular $Ca^{2+}$ through the release of endothelium derived relaxing factor including nitric oxide, prostacyclin, endothelium derived hyperpolarizing factor. And LC exerts a relaxing effect on corpus cavernosum through activating the NO.

• BMB Reports
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• v.31 no.2
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• pp.117-122
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• 1998

Changes of lipocortin 1 (LC1) in the brain induced by immobilization stress were investigated in rats. Rats were immobilized for 0,1,2,3,4, and 5 h, and the brain slices were immunostained with anti-human LC1 antibodl (anti-LC1). Immunoreactivity of LCI (iLC1) was most prominent in neuronal cell bodies and processes of hippocampal CA regions and dentate gyrus. At rest without stress, most of the LC1 in the neuron located in the cytoplasm with the nuclei exhibiting relatively scarce immunoreactivity. Immobilization stress changed this intracellular distribution of LC1 by increasing nuclear LC1. The change was apparent in 1 h and reached the peak by 3 h. However, by 5 h of immobilization, the distribution pattern returned to that of the resting state. This transient nuclear translocation of LC1 was most prominent in $CA_1$ pyramidal neurons, and was not observed in areas other than the hippocampus. Adrenalectomy abolished this transient translocation of LC1. The roles of hippocampal LC1 as a mediator of glucocorticoid feedback signal and/or as an intracellar stress signaling protein could be suggested.

• Biomolecules & Therapeutics
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• v.27 no.1
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• pp.34-40
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• 2019

Transglutaminase 2 (TGase 2) plays a key role in p53 regulation, depleting p53 tumor suppressor through autophagy in renal cell carcinoma. We found that microtubule-associated protein 1A/1B-light chain 3 (LC3), a hallmark of autophagy, were tightly associated with the level of TGase 2 in cancer cells. TGase 2 overexpression increased LC3 levels, and TGase 2 knockdown decreased LC3 levels in cancer cells. Transcript abundance of LC3 was inversely correlated with level of wild type p53. TGase 2 knockdown using siRNA, or TGase 2 inhibition using GK921 significantly reduced autophagy through reduction of LC3 transcription, which was followed by restoration of p53 levels in cancer cells. TGase 2 overexpression promoted the autophagy process by LC3 induction, which was correlated with p53 depletion in cancer cells. Rapamycin-resistant cancer cells also showed higher expression of LC3 compared to the rapamycin-sensitive cancer cells, which was tightly correlated with TGase 2 levels. TGase 2 knockdown or TGase 2 inhibition sensitized rapamycin-resistant cancer cells to drug treatment. In summary, TGase 2 induces drug resistance by potentiating autophagy through LC3 induction via p53 regulation in cancer.

• Korean Journal of Pharmacognosy
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• v.19 no.4
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• pp.248-250
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• 1988

The application of LC/MS system with FRIT-FAB LC/MS interface in both positive and negative ion modes to the analytical separation of isomeric saponins was studied. The two isomeric saponins such as rosamultin and arjunetin were well separated and analyzed FRIT, FAB LC/MS system. This is another examples to structure elucidation of natural products.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1121-1124
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• 2007

Ink jet printing has been targeted as a key technology for OLED, TFT backplane and other organic semiconductor device fabrication. This presentation will concentrate on aspects of the IJ process, formulation design, jetting performance, interaction with the substrate and resultant printed device performance.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.419-422
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• 2004

In this paper, we propose a new metric called "dynamic gamma" to quantitatively evaluate the dynamic temporal response of an LC display device. The widely-used response time and corresponding 3-D bar graphs cannot fully describe the dynamic characteristics of an LC panel [1], and using response time to compare different LC panels and assessing the dynamic features of LC panels is difficult. On the other hand, the new metric MPRT mixes an LC panel's slow temporal response with its hold-type display effect. The proposed new metric, dynamic gamma, and corresponding 2-D plots, are arguably more suitable for quantitatively characterizing the dynamic characteristics of an LC panel, so comparing two LC panels becomes easy. Furthermore, dynamic gamma has the unique property that it can be used to quantify the limitations/capabilities and to assess the effectiveness of an overdrive mechanism for a particular LCD. In the paper, two LC panels using different technology are analyzed and compared using this new metric.

• Journal of Advanced Marine Engineering and Technology
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• v.19 no.3
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• pp.107-118
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• 1995

The characteristics of the current waveforms and 3$\Phi$ power waveforms of the variable speed 3$\Phi$ AC motor system driven by the single-pulse PWM investigated in this paper. The system is composed of a digital bridge inverter and low pass LC filter. It is confirmed that current waveforms and 3$\Phi$ power waveforms can be improved by utilizing the high order low pass LC filter than that of lower order through computer simulation. Also, we propose the low pass LC filter revised from the conventional LC filter.

• East Asian mathematical journal
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• v.24 no.4
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• pp.317-328
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• 2008

In this paper we introduce ${\pi}G{\alpha}$-LC sets, ${\pi}G{\alpha}-LC^*$ sets and ${\pi}G{\alpha}-LC^{**}$ sets and different notions of generalizations of continuous functions in topological space and discuss some of their properties. Further we prove pasting lemma for ${\pi}G{\alpha}-LC^{**}$ continuous functions and ${\pi}G{\alpha}-LC^{**}$ irresolute functions.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.159-162
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• 2006

We reviewed our recent advances in LC mixture development identifying the new classes of materials to yield LC mixtures with faster switching times and better reliability