• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1167-1174
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• 2013

Cancer cells exhibit increased demand for glutamine-derived carbons to support anabolic processes. Indeed, the spectrum of glutamine-dependent tumors and the mechanisms through which glutamine supports cancer metabolism remain areas of active investigation. In the present study, we investigated the effects of glutamine deprivation on the correlation between tightening of tight junctions (TJs) and anti-invasive activity in human prostate carcinoma LnCap cells. Glutamine deprivation markedly inhibited cell motility and invasiveness in a time-dependent manner. The anti-invasive activity of glutamine deprivation was associated with an increased tightness of the TJ, which was demonstrated by an increase in transepithelial electrical resistance (TER). The activities of matrix metalloproteinase (MMP)-2 and MMP-9 were inhibited in a time-dependent fashion by glutamine deprivation, which was correlated with a decrease in expression of their mRNA and proteins and up-regulation of tissue inhibitors of metalloproteinases (TIMPs) expression. Furthermore, glutamine deprivation repressed the levels of the claudin family members, which are major components of TJs that play a key role in the control and selectivity of paracellular transport. Moreover, the levels of E-cadherin, a type I transmembrane glycoprotein, and snail, an epithelial to mesenchymal transition regulator and zinc finger transcription factor, were markedly modulated by glutamine deprivation. Taken together, these findings suggest that TJs and MMPs are critical targets of glutamine deprivation-induced anti-invasion in human prostate carcinoma LnCap cells.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.4
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• pp.276-284
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• 2023

Nitrogen is a major and essential macronutrient for plant growth and development. However, excessive nitrogen application can lead to ecological pollution or greenhouse gas emissions, consequently resulting in climate change. In this study, we used 153 genetic resources of rice to evaluate the effects of the levels of nitrogen application on grain yield and yield-related traits. Significant differences were noted in the yield and yield-related traits of genetic resources between two nitrogen application levels, namely, 4.5 kg/10a (NN: normal nitrogen condition) and 9.0 kg/10a (LN: low-nitrogen condition). Among the tested traits, days to heading (DTH), clum length (CL), grain yield per plant (GYP), number of panicles per plant (NPP), and number of spikelets per panicle (NSP) decreased by 1.8 to 17.9% when the nitrogen application levels decreased from NN to LN. The 1,000-grain weight (TWG) and percentage of ripened grain (PRG) increased by 2.6 to 11.2% under these conditions. Based on nitrogen application levels, two-way analysis of variance (ANOVA) demonstrated significant differences in GYP, NPP, and PRG but not in NSP and TGW. NPP exhibited negative correlations with NSP (-0.44) and TGW (-0.44), and TGW displayed a negative correlation with PRG (-0.34), whereas, GYP exhibited a positive correlation with PRG (0.37) and NSP (0.38). A similar pattern was recorded under the LN condition. NPP, TGW, and PRG were clustered as PA (principle axis) 1 under the LN condition by factor analysis. NSP and GYP were clustered as PA (principle axis) 2. These results demonstrated NPP and NSP as the primary factors contributing to the decrease in grain yield under LN conditions. In conclusion, we selected eight genetic resources that exhibited higher GYP under both NN and LN conditions with higher NPP or NSP. These genetic resources can be considered valuable breeding materials for the adaptation of plants to nitrogen deficiency.

• Journal of Oriental Neuropsychiatry
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• v.14 no.2
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• pp.135-143
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• 2003

Objectives : The purpose of this study is to analyze and compare heart rate variability(HRV) of patient of twenties and thirties diagnosed as Kiwooljeung with healthy controls'. Methods : We measured HRV of 35 patient(20 to 39 years old, male 14, female 11) diagnosed as Kiwooljeung and 40 healthy controls(male 24, female 16). HRV was measured by SA-3000P(Medicore, Korea) for 5 minutes after 5 minutes resting. Results : 1. In time domain analysis, Mean pulse rate(PRT) in Kiwooljeung group was higher than healthy controls. Standard deviation of all normal N-N intervals (SDNN) in Kiwooljeung group was lower and the results of twenties and thirties were same. 2. In frequency domain analysis, total power(TP), very low frequency(VLF), low frequency(LF), high frequency(HF), Ln TP, Ln VLF, Ln LF, Ln HF in Kiwooljeung group were lower than healthy controls but LF/HF ratio was higher than healthy controls. 3. Comparing gender in Kiwooljeung group, LF/HF ratio in male was higher than female. Conclusions : This study suggests lower activity and imbalance of cardiac autonomous nervous system in Kiwooljeung with the age group between twenties and thirties.

• Journal of Microbiology and Biotechnology
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• v.19 no.7
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• pp.681-684
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• 2009

This study was carried out to evaluate the inhibitory effect of Flammulina velutipes extracts on tyrosinase activity and to identify its biologically active component. The ethyl acetate and n-butanol extracts showed potent tyrosinase inhibitory activities. Subsequently, fractions of the n-butanol extract showed only a partial tyrosinase inhibitory activity. The most active compound of tyrosinase inhibitory activity was identified from the ethyl acetate extract as 1',3'-dilinolenoyl-2'-linoleoylglycerol (LnLLn) by comparing its mass, $^1H-$, and $^{13}C-NMR$spectral data with those previously reported in the literature. LnLLn showed tyrosinase inhibitory activity with an $IC_{50}$value of 16.1 ${\mu}g/ml$. These results suggest that the ethyl acetate extract of F. velutipes could be applicable for the development of a new whitening agent.

• Proceedings of the KIEE Conference
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• 1989.07a
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• pp.302-305
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• 1989

Ac, dc and impulse dielectric strengths of $LN_2$ at 0.1MPa were investigated experimentally, referring to the behavior of thermally induced bubble, which might be generated at quenching condition of immerged-cooling superconducting devices. The experimental results show that the bubble shape under electric field stress depends significantly on the applied voltage waveform. With ac voltage, the breakdown voltage of $LN_2$ falls suddenly near to one of the saturated gas at the threshold heater power of boiling onset. In control to this, the reduction of impulse breakdown voltage with heater peter is gradual and the time to breakdown depends on the existence of thermal bubble. These breakdown characteristics can be explained satisfactorily by the bubble behavior under electric fields.

• The Korean Journal of Ceramics
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• v.5 no.4
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• pp.375-378
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• 1999

In tho XRD study of $56ZrF_4 \cdot34BaF_2 \cdot4AIF_3 \cdot(6-x)LaF_3 \cdotxLnF_3$ glassdLn=Ce, Nd, Gd, Th), halo pattern charactarktic fo an amorphous sample appeared. When the halo peak angle ($\theta_p$) was converted into a wavenumber with $Qp=4\pi sinG\pi/\lambda(\lambda$ is the wavolongth of the radialion used), it was found that the Qp values varied almost liuearly with the concentration 01 $LnF_3$. The emissiou spect1.a of $Ce^{3-}$-containing fluoride glasses nnder 273 nm excitation had a peak maximum at ea. 300 nm $(Ce^{3+}$ 5d-4f- transition). The maximal intensity of the fluorescence was observed when the $CeF_3$, content was extremely low (ca. 1 mol%j. DTA measurement revealed tbat these fluoride glasses had two crystallization temperatures. In $56ZrF_4. 34BaF_2. 4NF_3. (6-x)LaF_3 .xNdF_3$ glasses, the actmation energies of crystallization obtained from a Kssinger plot were 1.7 and 5.0 eV for the glass with x=2, and 1.9 and 5.6 eV for the glass with x=4.

• Journal of the Korean Society for Precision Engineering
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• v.34 no.4
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• pp.247-251
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• 2017

Titanium alloy has been widely used in the aerospace industry because of its high strength and good corrosion resistance. During cutting, the low thermal conductivity and high chemical reactivity of titanium generate a high cutting temperature and accelerates tool wear. To improve cutting tool life, cryogenic machining by using a liquid nitrogen (LN2) jet is suggested. In cryogenic jet cooling, evaporation of LN2 in the tank and transfer tube could cause pressure fluctuation and change the cooling rate. In this work, cooling uniformity is investigated in terms of liquid nitrogen jet pressure in cryogenic jet cooling during titanium alloy turning. Fluctuation of jet spraying pressure causes tool temperature to fluctuate. It is possible to suppress the fluctuation of the jet pressure and improve cooling by using a phase separator. Measuring tool temperature shows that consistent LN2 jet pressure improves cryogenic cooling uniformity.

• Progress in Superconductivity and Cryogenics
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• v.13 no.4
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• pp.10-13
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• 2011

For the operation of high temperature superconducting (HTS) power equipments, it is necessary to develop insulating materials and high voltage (HV) insulation technology at cryogenic temperature of bushing. In this paper, the surface flashover characteristics of various insulating materials in $LN_2$ are studied. These results are studied at both AC and impulse voltage under a non-uniform field. The negative impulse breakdown voltage of GFRP is slightly higher than the positive impulse breakdown voltage. The use of glass fiber reinforced plastic (GFRP) and polytetrafluoroethylene (PTFE, Teflon) as insulation body for HTS bushing should be much desirable. Especially, GFRP is excellent material not only surface flashover characteristics but also mechanical characteristics at cryogenic temperature. The surface flashover is most serious problem for the shed design in $LN_2$ and operation of superconducting equipment.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.05a
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• pp.187-191
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• 2002

The characteristics of Electrical breakdown liquid nitrogen($LN_2$) were studied under simulated Quenching conditions for application of HTS apparatus. The experimental results for various quench condition revealed that the breakdown voltage of $LN_2$ with bubble flow velocity and gap spacing, Also, it did a electric field and potential distribution interpreting at the liquid nitrogen when the bubble existed, The plots of equipotential lines for three cases are also shown.

• Bulletin of the Korean Chemical Society
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• v.21 no.2
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• pp.259-263
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• 2000