• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.12
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• pp.1091-1098
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• 1998

Thermal stability of the electroless deposited Cu thin film was investigated. Cu/TaN/Si multilayer was fabricated by electroless-depositing Cu thin layer on TaN diffusion barrier layer which was deposited by MOCVD on the Si substrate, and was annealed in $H_2$ ambient to investigate the microstructure of Cu film with a post heat-treatment. Cu thin film with good adhesion was successfully deposited on the surface of the TaN film by electroless deposition with a proper activation treatment and solution control. Microstructural property of the electroless-deposited Cu layer was improved by a post-annealing in the reduced atmosphere of $H_2$ gas up to $600^{\circ}C$. Thermal stability of Cu/TaN/Si system was maintained up to $600^{\circ}C$ annealing temperature, but the intermediate compounds of Cu-Si were formed above $650^{\circ}C$ because Cu element passed through the TaN layer. On the other hand, thermal stability of the Cu/TaN/Si system in Ar ambient was maintained below $550^{\circ}C$ annealing temperature due to the minimal impurity of $O_2$ in Ar gas.

• Journal of dental hygiene science
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• v.6 no.4
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• pp.295-302
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• 2006

This study was conducted to study the effects of the TA Theory and the TA Program, an educational testing tool developed to improve functional communication skills for dental hygienists. The results taken from the experiment using the TA program has been verified by Examination Tool for Personnel Communication developed by Chung(2001). 44 in two experimental groups and 16 in control group took part in TA Program training sessions. The experimental Group I received TA technique training session for 12 hours per day in a period of three days and Group II for 6 hours per day in a period of two days. From this experiment, the following conclusion was obtained. The results are as follows: 1) As it can be seen from the results of the examination taken prior to the experiment, the subjects of the control group and experimental groups were homogenous in all categories including self-disclosure, awareness, evaluation and acceptance of feedback, self-expression, coping with feelings, clearness, avoidance, dominance, handling of differences, and perceived acceptance. 2) After the training of TA Program was completed on Group I and II, the examination results are as follows: Control Group (1.5158), Group I (1.8260) / Control Group (1.4684), Group II (1.9985). The results of Group I and II (1.7970 and 1.9985 respectively) therefore showed a meaningful difference. 3) From the results of the experiment it is shown that dental hygienists' communication skills improved after receiving the TA Program training. Therefore TA Program may be used as an effective tool for such purpose. 4) As it can be observed from the data, Group I and II showed difference in the degree of improvements. Therefore, there needs to be a further investigation on the effects of the difference in training period. 5) This program is not only limited to the education of dental hygienists but may be widely applied to various forms of education and teaching methods.

• Korean Journal of Materials Research
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• v.11 no.12
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• pp.1080-1085
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• 2001

Dielectric properties and leakage current characteristics of 100 nm-thick $Ta_2O_5/Al_2O_3$multilayer thin films, which were fabricated by reactive sputtering of$Al_2O_3$and$Ta_2O_5$ successively on top of each other for total 9 layers, have been investigated with variation of the$Al_2O_3$content$(i.e,\;Ta_2O_5/Al_2O_3 \;thickness\;ratio)$.$Ta_2O_5/Al_2O_3$films were amorphous regardless of the$Al_2O_3$content. With increasing the$Al_2O_3$content from 0% to 100%, refractive index of the $Ta_2O_5/Al_2O_3$films decreased linearly from 2.03 to 1.56 and dielectric constant was lowered from 23.9 to 7.7 Variation of the dielectric constant with the$Al_2O_3$content was in good agreement with the behavior that was obtained by assuming parallel capacitors of$Al_2O_3$and Ta_2O_5$. Leakage current characteristics of $Ta_2O_5/Al_2O_3$ multilayer films were superior to those of $Ta_2O_5$ and$Al_2O_3$films. $Ta_2O_5/Al_2O_3$ films of 5% and 10%$Al_2O_3$content exhibited excellent leakage current densities which were lower than $10^{-7} A/cm^2$ at 1MV/cm.

• Korean journal of food and cookery science
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• v.11 no.1
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• pp.77-82
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• 1995

Croaker and pork were cooked by four kinds of methods(boiled, broiled, deep fried, pan fried) and their extracts were extracted with 50% methanol. The Ames test were performed on these methanol extracts, employing Salmonella typhimurium tester strain TA98 and TA100, with and without S9 mix and after nitrite treatment. The methanol extracts of cooked croaker and pork showed mutagenicity between original weight 0.0125 g/plate and 0.1 g/plate in all strains and induced a higher mutagenicity in all strains with S9 mix than without S9 mix. In all kinds of cooking methods, pork extracts showed higher mutagenicities than croaker extracts and especially the extract of pan fried croaker and pork showed high mutagenicities with S9 mix. The extract after nitrite treatment showed higher mutagenicities than that after non treatment and after treatment with nitrite, the mutagenicities of extracts were higher on TA98 than TA100.

• The Korean Journal of Food And Nutrition
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• v.16 no.4
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• pp.303-309
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• 2003

This study was performed to investigate the antimutagenic and antioxidative activities of pine pollen with respect to the microbial mutation induced by various mutagens such as 1-NP, daunomycin, 2-NF, MNNG, NaN$_3$, 4NQO, 4-NOPD, AFB$_1$, Trp-P-1, 2-AF and oxidative mutagens such as t-BOOH, H$_2$O$_2$. Pine pollen, originally extracted with hexane, was reextracted with 70% methanol. The results obtained using the methanol extract, in terms of the antimutagenicity observed in relation to ten kinds of mutagens, showed that it exhibited 17.8, 82.2 and 80.9% inhibitory effects against daunomycin, AFB$_1$, and Trp-P-1, respectively, in Salmonella. typhimurium TA98 and a 72.3% inhibitory effect against AFB$_1$in S. tyPhimurium TA100. In terms of the antimutagenicity exhibited in relation to t-BOOH, a 72.3% inhibitory effect was observed, but no antimutagenicity was observed in relation to the other mutagens and strains. The methanol extract was further fractionated by chloroform, ethyl acetate, n-butanol. In S. typhimurium TA98, the chloroform(150 $\mu\textrm{g}$/plate) fraction showed strong antimutagenic effects of 55.6%, 93.7% and 93.5%, while the ethyl acetate(100 $\mu\textrm{g}$/plate) fraction showed 11.4%, 74.3% and 85.2% in relation to the mutagenicity induced by daunomycin, AFB$_1$and Trp-P-1, respectively. In S. typhimurium TA100, the chloroform and ethyl acetate fractions showed antimutagenic effects of 95.1% and 62.5%, respectively, on the mutagenicity induced by AFB$_1$. In S. typhimurium TA102, the chloroform fraction showed an antimutagenic effect of 93.6% on the mutagenicity induced by t-BOOH.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.5
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• pp.231-237
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• 2001

Etch rates up to 120 nm/min for $Ta_{2}O_{5}$ were achieved in both $SF_{6}/Ar$ and $Cl_{2}/Ar$ discharges. The effect of ultraviolet (UV) light illumination during ICP etching on $Ta_{2}O_{5}$ etch rate in those plasma chemistries was examined and UV illumination was found to produce significant enhancements in $Ta_{2}O_{5}$ etch rates most likely due to photoassisted desorption of the etch products. The effects of ion flux, ion energy, and plasma composition on (Ba, Sr)$TiO_3$ etch rate were examined and maximum etch rate ~90 nm/min was achieved in $Cl_{2}/Ar$ ICP discharges while $CH_{4}/H_{2}/Ar$ chemistry produced extremely low etch rates (${\leq}10\;nm/min$) under all conditions.

• Journal of the Korean Ceramic Society
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• v.31 no.11
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• pp.1299-1306
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• 1994

Effect of MgO content on microstructural evolution and microwave dielectric properties of Ba(Mg1/3Ta2/3)O3 system was investigated. MgO content was varied from 10 mol% deficiency to 10 mol% excess of stoichiometric composition, respectively. It was found that MgO-deficient specimen showed faster grain growth rate than stoichometric and MgO excess BMT system. Besides, sandwich type precipitates of Ba5Ta4O15 which was formed within the BMT grain, might lead to the anisotropic grain growth of BMT grain. On the contrary, in MgO excess specimen, BMT grain growth rate was retarded by precipitations of MgO phase in grain boundary. Besides, the Q values of MgO-deficient showed lower than MgO-excess due to precipitations of Ba5Ta4O15 within BMT grain.

• Clinical and Experimental Pediatrics
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• v.59 no.sup1
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• pp.145-148
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• 2016

Takayasu arteritis (TA) is a chronic inflammatory disease of unknown etiology that affects mainly the aorta, main aortic branches, and pulmonary arteries. Diverse neurological manifestations of TA have rarely been reported in children. Posterior reversible encephalopathy syndrome (PRES) is a neuroradiological condition that presents with headache, seizure, visual disturbances, and characteristic lesions on imaging. Inflammatory condition and severe hypertension in TA can cause PRES. We report of a 5-year-old girl with presumed TA who presented with PRES and chronic total occlusion in the renal artery. The findings on magnetic resonance imaging suggested PRES. Left nephrectomy was performed for total occlusion of the left renal artery, and the confirmatory diagnosis of TA was based on the pathologic findings of the renal artery.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05c
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• pp.249-252
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• 2003

The microwave dielectric properties of $0.7Mg_4Ta_2O_9-0.3TiO_2$ ceramics were investigated. All samples were prepared by the conventional mixed oxide method. The structural properties were investigated with sintering temperature by X-ray Diffractor meter. According to. the X-ray diffraction patterns of the $0.7Mg_4Ta_2O_9-0.3TiO_2$ ceramics, major phase of the hexagonal $Mg_4Ta_2O_9$ were appeared. In the case of $0.7Mg_4Ta_2O_9-0.3TiO_2$ ceramics sintered at $1400^{\circ}C$, dielectric constant, quality factor and temperature coefficient of resonant frequency were 11.72, 126,419GHz, $-31.82ppm/^{\circ}C$, respectively.

• Radiation Oncology Journal
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• v.11 no.2
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• pp.397-401
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• 1993

We investigated the usefulness of tumor-associated antigen (TA-4) by a radioimmunoasay method in estimating the extent of disease and tracking the clinical course of disease in 58 patients with cervical cancer. According to our results and those of other authors, the normal range of serum TA-4 was arbitrarily taken to be less than 2 ng/ml. The proportion of the pretreatment positive serum TA-4 level of 48 squamous cell carcinoma patients was $60\%.$ And $40\%$ in 5 adenocarcinoma patients. Advanced disease group showed higher incidence of positive serum TA-4 level; $40\%,\;72\%,\;63\%,\;and\;100\%$ in stage I to IV, respectively. And the absolute values of TA-4 were higher in advanced disease. In patients treated with radiation, elevated serum TA-4 level usually declined after 3000 cGy and further dropped to normal range in $44\%$ after 5000 cGy. The positive rate in primary cervical cancer was $59\%,$ (32/54) and $100\%$ (4/4) in recurrent conical cancer. And 15 patients with recurrent or persistent disease during follow-up revealed $80\%$ positive serum TA-4 level. In conclusion, it would be suggested that serial serum TA-4 measurements may be helpful in tracking the clinical course during and after treatment.