• The Korea Journal of Herbology
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• v.31 no.1
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• pp.25-31
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• 2016

Objectives : The present study was conducted to evaluate protective effects of Combined Extract of young persimmon fruit and citrus peel (PCM) in Reflux Esophagitis(RE) rats.Methods : Twenty-four Sprague-Dawley (SD) rats were divided four groups and each group had six rats ; Normal group, RE control group, RE group treated PCM 50 ,100 mg/kg body weight group. Reflux esophagitis was induced that tied the pylorus and fundus in SD rats stomach. PCM was administered at 50, 100 mg/kg body weight 2 hrs prior to induction of RE. After 6 hrs, the effects of PCM treated rats were compared with those of normal and control rats. We have performed an analysis such as pH of stomach secretion, oxidative stress biomarkers in serum, and western blot.Results : The increased esophageal mucosa damage by RE was markedly improved by PCM treatment in a dose-dependent manner. Also, the administration of PCM decreased the elevated serum reactive oxygen species (ROS) and peroxynitrite (ONOO^-) in serum. The protein expressions of anti oxidant such as SOD, catalase, GPx exhibited down-regulation by PCM treatment in tissues. And, PCM effectively reduce inflammatory cytokines such as inflammation-related proteins cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), Tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) in RE rats. In addition, NFκB and p-IκBɑ were decreased in PCM-adiministrated RE rats. But there was no difference on stomach secretion pH between reflux esophagitis rats and PCM administration rat group.Conclusions : In conclusion, administration of PCM (50, 100 mg/kg body weight) made esophagus have less inflammation and injury by decreased NFκB path way. These findings suggest that PCM could have Improving effects on reflux esophagitis.

• Journal of Ginseng Research
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• v.37 no.3
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• pp.283-292
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• 2013

Ginsenosides are divided into two groups based on the types of the panaxadiol group (e.g., ginsenoside-Rb1 and -Rc) and the panaxatriol group (e.g., ginsenoside-Rg1 and -Re). Among them, ginsenoside-Re (G-Re) is one of the compounds with the highest content in Panax ginseng and is responsible for pharmacological effects. However, it is not yet well reported if G-Re increases the hemodynamics functions on ischemia (30 min)/reperfusion (120 min) (I/R) induction. Therefore, in the present study, we investigated whether treatment of G-Re facilitated the recovery of hemodynamic parameters (heart rate, perfusion pressure, aortic flow, coronary flow, and cardiac output) and left ventricular developed pressure (${\pm}dp/dt_{max}$). This research is designed to study the effects of G-Re by studying electrocardiographic changes such as QRS interval, QT interval and R-R interval, and inflammatory marker such as tissue necrosis factor-${\alpha}$ (TNF-${\alpha}$) in heart tissue in I/R-induced heart. From the results, I/R induction gave a significant increase in QRS interval, QT interval and R-R interval, but showed decrease in all hemodynamic parameters. I/R induction resulted in increased TNF-${\alpha}$ level. Treatment of G-Re at 30 and $100{\mu}M$ doses before I/R induction significantly prevented the decrease in hemodynamic parameters, ameliorated the electrocardiographic abnormality, and inhibited TNF-${\alpha}$ level. In this study, G-Re at $100{\mu}M$ dose exerted more beneficial effects on cardiac function and preservation of myocardium in I/R injury than $30{\mu}M$. Collectively, these results indicate that G-Re has distinct cardioprotectective effects in I/R induced rat heart.

• Korean Journal of Poultry Science
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• v.34 no.1
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• pp.23-29
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• 2007

Rare earth(RE) is a common name indicating 17 of specific elements including 15 of lanthanides, scandium (Sc), and yttrium(Y). This study was conducted to compare the effect of RE to growth stimulating antibiotic products in broiler diet. One of the products commonly used in broiler feeding, Chlorotetracycline(CTC) was used at a level of 200ppm for the antibiotic treatment and replaced by 100ppm RE for the RE treatment. Dietary addition of RE and CTC showed similar effects in improving broiler growth and feed conversion each other, and those were significantly better when compared to those of the control group(P<0.05). Abdominal fats of chicks fed RE were significantly lower than others(P<0.05). Intestinal E. coli and total microbial numbers were reduced by RE addition(P<0.05), but the number of Lactobacillus was not affected. The number of Salmonella was also decreased but it was not significant.

• Journal of the Korean Society of Radiology
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• v.14 no.4
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• pp.447-453
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• 2020

This study accurately measured the half-life of the ¹⁷⁹Re radioactive isotope using the 100 MeV proton and high-purity HPGe gamma ray measurement system generated from a high-energy proton linear accelerator at the Korea Atomic Energy Research Institute. The result obtained is 19.64 ± 0.26 min. Compared with the past results of the half-life of the ¹⁷⁹Re radioisotope known to date, the results of B. Harmatz published in 1960 and B. J. Meijer published in 1975 measured the median value higher than the results obtained in this study. In the case of K. J. Hofstetter, published in 1966, a very large error is also characteristic. This result showed a tendency that the center value was very consistent with the result of this study. The results of Coral M. Baglin's 19.5 min published in 2009 are very consistent with the error range. The obtained measured result was compared with the result of ENSDF (Evaluated Nuclear Structure Data File). Through this study, more reliable values were measured for the results of the half-life of the ¹⁷⁹Re, which was previously incorrect, and the validity of the recently published results of Coral M. Baglin was confirmed.

• Journal of the Korean Society of Radiology
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• v.15 no.2
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• pp.257-263
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• 2021

This study derives the relative cross-section for the natW(p,xn)176Re nuclear reaction by measuring the gamma rays generated from the nuclear reaction with natural tungsten using a 100 MeV linear accelerator of the Korea Multi-purpose Accelerator Complex in the Korea Atomic Energy Research Institute. In general, research on isotopes with a short half-life always shows a tendency that the intensity of radioactivity decreases rapidly within a short period of time, making it very difficult to measure itself. In particular, 176Re is one of the relatively short radionuclides with a half-life of 5.3 minutes. In this study, 109.08 keV gamma rays generated from the 176Re isotope having such a short half-life were measured using a high-purity Ge detector(HPGe detector). The obtained relative measurements were the results in the 8 to 14 MeV proton energy domain published by Richard G. in 1967, and the TENDL-2019 value, which was the result of A. J. Koning in 2019, which evaluated the nuclear reaction cross-section by calculation based on this comparative analysis was performed. The results of this study are expected to be usefully applied to the design of nuclear fusion reactor which is known as future energy sources, elements ratio for the nuclear synthesis of astrophysics.

• Journal of Radiation Industry
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• v.6 no.3
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• pp.281-287
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• 2012

The model plant, Arabidopsis thaliana is the subject of an international genome research project. Massive doses of ionizing radiation have been shown to induce physiological changes in plants. The wild-type (Ler) Arabidopsis plants were irradiated with 100 Gy and 800 Gy of gamma-ray. Gibberellin (GA) affects developmental processes and responses according to the various environment conditions in diverse plant. The 13 GA isomers were analyzed at vegetative (VE) and reproductive (RE) stages by HPLC. Total GA contents were reduced with the increase in radiation doses at VE and RE stages. Specifically, levels of GA3, GA4, GA12, and GA34 were significantly reduced with the increase of radiation doses. Oligonucleotide microarrays analysis was performed with Arabidopsis plants at different developmental stages and doses of gamma-ray. Through the microarray data, we isolated 41 genes related to GA biosynthesis and signaling transduction. Expression of these genes was also decreased as the reduction of GA contents. Interestingly, in GA signaling related gene expression, gibberellin-responsive protein, putative (At2g18420) was down-regulated at VE and RE stages. Myb21 (At3g27810), Myb24 (At5g40350), and Myb57 (At3g01530) was down-regulated at RE stage. In GA biosynthesis related gene expression, YAP169 (At5g07200) and GA20ox2 (At5g51810) were down-regulated at 100 Gy treatment of VE stage and 800 Gy treatment of RE stage in cytoplasm, respectively. However, exceptively, GA3ox2 (At1g80340) was up-regulated at 100 Gy treatment of RE stage in cytoplasm. In this study, the wild type (Ler) Arabidopsis plants showed differences in response with development stage at the various doses of gamma-rays. GA contents change was reported in gamma irradiated plant.

• Korean Journal of Social Welfare
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• v.57 no.2
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• pp.375-403
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• 2005

This Study reviews theoretical argument about the effect of retirement earnings test on the labor supply of the aged which is controversial issue in OECD countries and analyze the effect on the incidence of re-employment, re-employment period of suspended officials and the possibility of re-retirement through Government Employment Pension Corporation data. It consists of 178,363 public officials who received pension benefit or disability pension in January 2005. The main result of this research shows that public officials re-employed were 8,086 which is 4.5% of total retired, and median survival time of suspended pension payments is 3.3 years. Also the median re-employment period of 100% suspended officials is about 20 month shorter than that of 1/2 suspended officials and it is shown in regression analysis that the possibility of re-retirement by 100% suspended officials is statistically significant higher than those of 50%. It specially expects greater influence if includes in case taking lump-sum or no making effect of re-employment because current system withhold pension payments even by earned income itself. Therefore, this analysis suggests suspension of pension payment properly applied according to the age and income together with "Delayed Retirement Credit" or "Partial Pension" for developmental alternatives of civil servant's suspension of pension payments. Furthermore, It is urgently needed that distinctive quality data about re-employment including earnings to perform deep-empirical research for effective policy. Lastly, it is extremely necessary to reinforce management system of Government Employment Pension Corporation.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.257-257
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• 2016

최근에 메모리의 초고속화, 고집적화 및 초절전화가 요구되면서 resistive random access memory (ReRAM), ferroelectric RAM (FeRAM), phase change RAM (PRAM)등과 같은 차세대 메모리 기술이 활발히 연구되고 있다. 다양한 메모리 중에서 특히 resistive random access memory (ReRAM)는 빠른 동작 속도, 낮은 동작 전압, 대용량화와 비휘발성 등의 장점을 가진다. ReRAM 소자는 절연막의 저항 스위칭(resistance switching) 현상을 이용하여 동작하기 때문에 SiOx, AlOx, TaOx, ZrOx, NiOx, TiOx, 그리고 HfOx 등과 같은 금속 산화물에 대한 연구들이 활발하게 이루어지고 있다. 이와 같이 다양한 산화물 중에서 AlOx는 ReRAM의 절연막으로 적용되었을 때, 우수한 저항변화특성과 안정성을 가진다. 하지만, AlOx 박막을 형성하기 위하여 기존에 많이 사용되어지던 PVD (physical vapour deposition) 또는 CVD (chemical vapour deposition) 방법에서는 두께가 균일하고 막질이 우수한 박막을 얻을 수 있지만 고가의 진공장비 사용 및 대면적 공정이 곤란하다는 문제점이 있다. 한편, 용액 공정 방법은 공정과정이 간단하여 경제적이고 대면적화가 가능하며 저온에서 공정이 이루어지는 장점으로 많은 관심을 받고 있다. 본 연구에서는 sputtering 방법과 용액 공정 방법으로 형성한 AlOx 기반의 ReRAM에서 메모리 특성을 비교 및 평가하였다. 먼저, p-type Si 기판 위에 습식산화를 통하여 SiO2 300 nm를 성장시킨 후, electron beam evaporation으로 하부 전극을 형성하기 위하여 Ti와 Pt를 각각 10 nm와 100 nm의 두께로 증착하였다. 이후, 제작된 AlOx 용액을 spin coating 방법으로 1000 rpm 10 초, 6000 rpm 30 초의 조건으로 증착하였다. Solvent 및 불순물 제거를 위하여 $180^{\circ}C$의 온도에서 10 분 동안 열처리를 진행하였고, 상부 전극을 형성하기 위해 shadow mask를 이용하여 각각 50 nm, 100 nm 두께의 Ti와 Al을 electron beam evaporation 방법으로 증착하였다. 측정 결과, 용액 공정 방법으로 형성한 AlOx 기반의 ReRAM에서는 기존의 sputtering 방법으로 제작된 ReRAM에 비해서 저항 분포가 균일하지는 않았지만, 103 cycle 이상의 우수한 endurance 특성을 나타냈다. 또한, 1 V 내외로 동작 전압이 낮았으며 104 초 동안의 retention 측정에서도 메모리 특성이 일정하게 유지되었다. 결론적으로, 간단한 용액 공정 방법은 ReRAM 소자 제작에 많이 이용될 것으로 기대된다.

• Journal of the Korean Vacuum Society
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• v.6 no.3
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• pp.194-199
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• 1997

We fabricated MIM (Metal-Insulator-Metal) antifuses with Al/a-Si/Mo structure and then examined the I-V characteristics and on-state resistance distribution of antifuses. The leakage current of antifuses is below $1Pa/{\mu}m^2$, and programming voltage lies within 10 to 11 V. After programming, on-resistance of antifuses is mostly 10-20$\Omega$ and 20% of these have above 100$\Omega$. In order to reduce on-resistance and the deviation of this distribution, we tried to inject current again into already programed antifuses (we call this re-programming method). From this method, the resistance of antifuses with above 100Ω can be reduced to below 50$\Omega$. When antifuses are programmed by re-programming method, these antifuses have more uniform and lower on-resistance than programmed with one-pulse.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.117-122
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• 2001

Recently, epoxy-coated re-bar used to the structure partly and put to practical use step, but not economical and appeared to the defect of deterioration of long term bond strength between concrete. The method for complement the defect of epoxy coated re-bar, study of polymer cement slurry coated re-bar started and basic properties appeared to excellent, but study of bond properties embedded in concrete specimens insufficient until now. This study attempts to examination of using possibility for bond strength of polymer cement slurry coated re-bar between concrete specimens compare to ACI Code and KS Code through pull-out test of 15cm$\times$15cm$\times$15cm specimens with polymer cement slurry coated re-bar as polymer cement ratio 50%, 100%, 150%, coating thickness 250${\mu}{\textrm}{m}$, 440${\mu}{\textrm}{m}$ and curing age. In the results of this study, the bond strength of polymer cement slurry coated re-bar compare to plain re-bar, epoxy coated re-bar decreased St/BA-modified polymer cement slurry coated re-bar, but bond strength of PA-modified polymer cement slurry coated re-bar appeared to excellent results. The bond properties of polymer cement slurry coated re-bar between concrete will be obtain more precise results according to compressive strength change of concrete and re-bar diameter size.