• The Journal of Advanced Prosthodontics
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• v.9 no.4
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• pp.244-251
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• 2017

PURPOSE. The purpose of this study was to determine fracture resistance and failure modes of three-unit fixed dental prostheses (FDPs) made of lithium disilicate pressed on zirconia (LZ), monolithic lithium disilicate (ML), and monolithic zirconia (MZ). MATERIALS AND METHODS. Co-Cr alloy three-unit metal FDPs model with maxillary first premolar and first molar abutments was fabricated. Three different FDPs groups, LZ, ML, and MZ, were prepared (n = 5 per group). The three-unit FDPs designs were identical for all specimens and cemented with resin cement on the prepared metal model. The region of pontic in FDPs was given 50,000 times of cyclic preloading at 2 Hz via dental chewing simulator and received a static load until fracture with universal testing machine fixed at $10^{\circ}$. The fracture resistance and mode of failure were recorded. Statistical analyses were performed using the Kruskal-Wallis test and Mann-Whitney U test with Bonferroni's correction (${\alpha}=0.05/3=0.017$). RESULTS. A significant difference in fracture resistance was found between LZ ($4943.87{\pm}1243.70N$) and ML ($2872.61{\pm}658.78N$) groups, as well as between ML and MZ ($4948.02{\pm}974.51N$) groups (P<.05), but no significant difference was found between LZ and MZ groups (P>.05). With regard to fracture pattern, there were three cases of veneer chipping and two interfacial fractures in LZ group, and complete fracture was observed in all the specimens of ML and MZ groups. CONCLUSION. Compared to monolithic lithium disilicate FDPs, monolithic zirconia FDPs and lithium disilicate glass ceramics pressed on zirconia-based FDPs showed superior fracture resistance while they manifested comparable fracture resistances.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.24
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• pp.10967-10970
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• 2015

Objective: To analyze the efficacy and survival associated factors of gefitinib combined with cisplatin and gemcitabine for advanced non-small cell lung cancer. Materials and Methods: A total of 57 patients with advanced non-small cell lung cancer (NSCLC), who received platinum-based chemotherapy regimens for more than 1 cycle, were treated with gefitinib combined with cisplatin and gemcitabine until disease progression. Efficacy, survival time and adverse reactions were observed. The Kaplan-Meier method was adopted for analysis of survival and Cox regression for associated influencing factors. Results: The patients were followed up until October 31, 2013, and the median follow-up time was 19 months. Of 57 patients, there were 4 (7.0%) with complete remission (CR), 8 (14.0%) with partial remission, 31 (54.4%) with stable disease, and 14 (24.6%) with disease progression. The remission rate was 21.1% and the disease control rate was 75.4%. The median progression-free survival (PFS) time and the median overall survival time were 10 months and 15.2 months. The one-year, two-year and three-year survival rates were 47.4%, 23.3% and 10.0%. Gender and pathological types were the independent risk factors influencing PFS time (P=0.028, P=0.009). Tumor pathological type and early efficacy were independent factors for the prognosis (P=0.018, P=0.000). Adverse reactions were mostly rashes of I~II degree and diarrhea and slightly increasing level of aminopherase. The skin adverse event incidence of III degree or above was 1.8% (1/57) and brain metastasis was foudn in 31.6% (18/57). Conclusions: Gefitinib combined with cisplatin andgemcitabine, is effective for patients with IIIb~IV NSCLC who received multiple cycles of chemotherapy.

• The Journal of Korean Academy of Prosthodontics
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• v.35 no.4
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• pp.647-661
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• 1997

The resin modified glass ionomer cements(RMGICs) have been used for years since 1989. Recently it has been developed for luting of fixed restorations. To evaluate the bond strength and marginal leakage of RMGICs for luting usage, the 80 extracted human molars which had uniform area of exposed dentin were cemented with 3 types of RMGICs(Fuji Duet, Advance, Vitremer), a conventional Glass Ionomer Cement(GIC-Fuji I), and a resin cement (Panavia 21) to base metal alloy(Ni-Cr-Be). After thermocycling the specimens were immersed in basic fuschin dye for measuring marginal leakage. The shear bond strength was measured with Instron and the maximum dye penetration was measured to 0.1mm. The types of fractured patterns were determined with stereoscope(${\times}7.5$). The results are as follows. 1. The difference between 3 RMGICs and a conventional GIC in shear bond strength was not statistically significant. It seemed that RMGICs had lower shear bond strength than resin cement. (p<0.01) 2. The mean scores of marginal leakage had no significant difference between the resin cement and 3 RMGICs but it was much higher in conventional GIC than the RMGICs (p<0.05) 3. It was determined that the manufacturer and the methods of dentin pretreatment determined the pattern of fracture surfaces and the frequency of adhesive failure between teeth and 3 RMGICs standed as in following order - Vitremer, Advance, Fuji Duet. (p<0. 01) When the fracture pattern was analyzed, it could be said that the materials and the method of dentin pretreatment have much effect on bonding states. This means that the dentin bonding agents should be improved. But the limited products in this experiment can not evaluate the physical properties of the entire RMGICs. Therefore a further study which can evaluate various RMGICs should be in progress to develope better cements.

• Clinical and Experimental Pediatrics
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• v.58 no.11
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• pp.421-426
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• 2015

Purpose: The vancomycin dosage regimen is regularly modified according to the patient's glomerular filtration rate (GFR). In the present study, we aimed to assess the usefulness of serum cystatin C (Cys-C) concentration, compared with serum creatinine (SCr) concentration, for predicting vancomycin clearance (CLvcm) in neonates. Methods: We retrospectively analyzed the laboratory data of 50 term neonates who were admitted to the neonatal intensive care unit and received intravenous vancomycin, and assessed the pharmacokinetic profiles. Creatinine clearance (CLcr) and GFR based on Cys-C (GFRcys-c) were estimated using the Schwartz and Larsson formulas, respectively. Results: The mean CLvcm (${\pm}$standard deviation) was $74.52{\pm}31.17L/hr$, the volume of distribution of vancomycin was $0.67{\pm}0.14L$, and vancomycin half-life was $9.16{\pm}17.42hours$. The SCr was $0.46{\pm}0.25mg/dL$ and serum Cys-C was $1.43{\pm}0.34mg/L$. The peak and trough concentrations of vancomycin were $24.65{\pm}14.84$ and $8.10{\pm}5.35mcg/mL$, respectively. The calculated GFR based on serum creatinine concentration (GFR-Cr) and GFRcys-c were $70.2{\pm}9.45$ and $63.6{\pm}30.18mL/min$, respectively. The correlation constant for CLvcm and the reciprocal of Cys-C (0.479, P=0.001) was significantly higher than that for CLvcm and the reciprocal of SCr (0.286, P=0.044). GFRcys-c was strongly correlated with CLvcm (P=0.001), and the correlation constant was significantly higher than that for CLvcm and CLcr (0.496, P=0.001). Linear regression analysis showed that only GFRcys-c was independently and positively correlated with CLvcm (F=41.9, P<0.001). Conclusion: The use of serum Cys-C as a marker of CLvcm could be beneficial for more reliable predictions of serum vancomycin concentrations, particularly in neonates.

• Reproductive and Developmental Biology
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• v.33 no.4
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• pp.257-262
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• 2009

This study was to investigate pregnancy rate of IVM/IVF/IVC Korean cattle (registered in government) embryos according to transport time course. For the production of embryos, oocytes recovered from slaughtered excellent grade cow and highly motile frozen-thawed bull semen (purchased from LIMC, KPN#497) was used. In vitro produced embryos were cultured in CR1aa medium for 8 days and some of them were frozen. The rate of average cleavage (>2-cell) was 83.0% (308/371) and blastocyst rate at day 8 was 34.7% (107/308). Among in vitro produced blastocyst embryos at day 8, most healthy embryos were freshly transferred on production day and some frozen embryos were direct transferred on appropriate day. These embryos were produced in a laboratory, embryo transfer (ET) was planned in 10 areas of the remote island (Jeju) from the laboratory by airplane. Thus, we examined the pregnancy rate in recipient cow according to embryo of transport time course before ET. From embryo transferred 44 recipient cows, overall pregnancy was 40.9% (18/44), these 18 cows were all calved [single, 94% (17/18); twin, 6% (1/18)] and total embryo implantation rate was 26% (19/66). Comparing transport time in the base of 6 hr, pregnancy rate in ET group required less 4 hr (60%, 9/15) was significantly higher than that required more 6 hr (26.3%, 5/19). In direct ET of freezing embryos, the pregnancy rate was 40% (4/10). However, it was difficult to find the meaning of temperature, pH and corpus luteum quality of recipients on comparison of pregnancy rate. When the cell death level of embryos according to storage time in thermos (straw container) before ET was measured by TUNEL staining, apoptotic index was increased with storage time-dependent. These results demonstrated that long distance transfer of IVM/IVF/IVC embryos is possible and the time of embryo transport is very important for the pregnancy rate on field trial.

• Economic and Environmental Geology
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• v.26 no.1
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• pp.41-54
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• 1993

The Ulsan Fe-W deposit, which can be classified as a calcareous skarn deposit, is represented by ore pipe consisting principally of magnetite and lesser amounts of scheelite with minor sulphides, sulphosaits, arsenides, sulpharsenides, etc. At Ulsan mine, metasomatic processes of skarn growth may be divided broadly into two stages based on the paragenetic sequence of calc-silicate minerals and their chemical composition; early and late skarn stages. Early stage has started with the formation of highly calcic assemblages of wollastonite, diopsidic clinopyroxene and nearly pure grossular, which are followed by the formation of clinopyroxenes with salite to ferrosalite composition and grandite garnets with intermediate composition. Based on these calc-silicate assemblages, the temperatures of early skarn formations have been in the ranges of $550^{\circ}$ to $450^{\circ}$. The calc-silicate assemblages formed during the earlier half period of late skarn stage show the enrichment of notable iron and slight manganese, and the depletion of magnesium; clinopyroxenes are hedenbergitic, and grandite garnets are andraditic. The formation temperatures during this skarn stage are inferred to have been in the range of $430^{\circ}$ to $470^{\circ}C$ at low $X_{CO_2}$ by data from fluid inclusions of late andraditic garnets. The later half period of late skarn stage is characterized by the hydrous alteration of pre-existing minerals and the formation of hydrous silicates. The main iron-tungsten mineralization representing prominent deposition of magnetite immediately followed by minor scheelite impregnation has taken place at the middle of early skarn stage, while complex polymetallic mineralization has proceeded during and after the late skarn stage. Various metals and semimetals of Fe, Ni, Co, Cu, Zn, As, Mo, Ag, In, Sn, Sb, Te, Pb and Bi have been in various states such as native metal, sulphides, arsenides, sulphosaits, sulpharsenides and tellurides.

• Korean Journal of Environmental Biology
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• v.24 no.1 s.61
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• pp.38-45
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• 2006

Ecological characteristics of microbial populations inhabiting heavy metal polluted soil were investigated. The samples were collected from 293 sites around an factory and industry at Gyeoungsangbuk-do. We measured the contents of seven heavy metal elements (Cd, Cu, As, Hg, Pb, $Cr^{6+}$, CN), seven sites have been seriously contaminated by mercury and chrome. A quantitative evaluation of microbial populations in mercury and chrome contaminated soil was examined by using plate count method. Bacterial numbers in polluted soil samples ranged from $7.4X10^5\;to\;9.3X10^7\;cfu\;g^{-1}$, about $10\sim100$ fold less than the count for the unpolluted soil. Moulds were not detected in chrome polluted soil. The log values of actinomycetes of each contaminated soil samples were log ranged from 6.18 to 7.52. The ratio of actinomycetes was similar to unpolluted soil. The investigation showed actinomycetes to be the major microbial population inhabiting the mercury and chrome polluted soil. Thirty-one isolates among the total isolates were examined for antibacterial activity. These isolates were identified based on a phylogenetic analysis using 16S rRNA gene nucleotide sequences, they were categorized in three major phylogenetic groups, belong to the Streptomyces (6 strains), Saccharopolyspora (3 strains), Nocardiodes (1 strain). On the phylogenetic tree, the clade consisting of five isolates were distantly related to all of the established Streptomycetes genera, indicating the possibility as members of new species.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1996.04a
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• pp.57-64
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• 1996

석탄중에는 미량원소(trace elements)가 포함되어 있으며 이들의 농도는 석탄의 종류나 산지에 따라 크게 다르다. 석탄중의 미량원소를 제거하는 것은 그동안 크게 문제가 되지 않았으나 최근 환경문제가 점차 고조되면서 이에 대한 관심이 높아지고 있다. 일반적으로 사람의 건강 및 환경에 유해한 원소중에서 화석연료 사용과 관련이 있는 원소는 비소(As), 카드늄(Cd), 납(Pb), 구리(Cu), 수은(Hg), 니켈(Ni), 셀레니움(Se) 및 아연(Zn) 등 8개 원소이다. 그러나 그외에도 배출규제의 대상이 되는 원소는 코발트(Co), 염소(Cl), 안티모니(Sb), 베릴리움(Be), 크롬(Cr)과 망간(Mn)이며 이중 망간은 석탄사용과 직접적인 관련이 있다. 따라서 Mn을 포함한 9개 원소가 석탄의 사용에 따른 중금속 방출과 관련이 있는 것으로 간주되고 있다. 본 연구에서는 발전용 석탄에 대한 물리적 전처리 공정을 적용하여 석탄중의 광물질등을 미리 제거하므로서 연소 후 배출되는 배기가스중의 중금속 저감 가능성을 관찰하였다. 본 연구결과 전처리 공정의 석탄중의 Trace elements양을 감소시키므로서 연소 후 중금속의 배출량을 크게 줄일 수 있음을 확인하였다. 발전소에 적용하고 있는 ESP가 배출가스중 As, Cu, Zn, Mn등의 중금속을 제거하는데 효율적이기는 하나 가스상으로 존재하는 Hg, Se등을 제거하는데는 효율적이지 못하다. 전처리공정 전후 회분중에 함유된 미량원소를 분석한 결과, 국내 무연탄이나 해외 유연탄 모두 중금속 제거에 있어서 유사한 경향을 보여주었으며, Pb, Zn, Mn 등은 50∼70%, 특히 Hg 배출량은 80% 이상 저감이 가능하였다. 전반적으로 년간 총 중금속 배출량도 50∼60%가 감소하여 전처리 공정이 석탄중의 중금속을 줄이는데 크게 기여함을 확인하였다.을 선택할 수 있는 메뉴 그리고 계산 결과를 파일로 혹은 프린트로 출력할 것을 선택할 수 있는 메뉴가 있다. 사용자는 해당되는 데이타를 입력한후 마우스로 원하는 작업의 메뉴를 선택하면 된다. 방법을 타액과 혈청내 testosterone 농도 측정에 응용하여 RIA의 결과와 비교하여 본 바 상관관계가 타액에서 r=0.969, 혈청에서 r=0.990으로 두 결과가 잘 일치하였다. 본 실험에서 측정된 한국인 여성의 타액내 testosterone농도는 107.7$\pm$12.0 pmol／l이었고, 남성의 타액내 농도는 274.2$\pm$22.1 pmol／l이었다. 이상의 결과로 보아 본 연구에서 정립된 EIA 방법은 RIA를 대신하여 소규모의 실험실에서도 활용할 수 있을 것으로 사려된다.또한 상실기 이후 배아에서 합성되며, 발생시기에 따라 그 영향이 다르고 팽창과 부화에 관여하는 것으로 사료된다. 더욱이, 조선의 ${\ulcorner}$구성교육${\lrcorner}$이 조선총독부의 관리하에서 실행되었다는 것을, 당시의 사범학교를 중심으로 한 교육조직을 기술한 문헌에 의해 규명시켰다.nd of letter design which represents -natural objects and was popular at the time of Yukjo Dynasty, and there are some documents of that period left both in Japan and Korea. "Hyojedo" in Korea is supposed to have been influenced by the letter design. Asite- is also considered to have been "Japanese Letter Jobcheso.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.15 no.4
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• pp.23-40
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• 2012

The vascular plants of major sites in Changwon-si were listed 456 taxa (9.3% of all 4,881 taxa of vascular plants); 112 families, 293 genera, 371 species, 2 subspecies, 66 varieties and 17 forms. The vascular plants of Changwon-cheon were listed 133 taxa, Junam reservoir were listed 90 taxa, Seongju-sa were listed 293 taxa, and Yungji park were listed 164 taxa. Divided into 456 taxa; woody plants were 160 taxa (35.1%) and herbaceous plants were 296 taxa (64.9%). Furthermore, therophytes (Th) were 111 taxa (24.3%), hemicryptophytes (H) were 75 taxa (16.4%), megaphanerophytes (MM) were 63 taxa (13.8%) showed high proportional ratio in life form. Based on the list of rare plants by the Korea Forest Service and Korea National Arboretum, 10 taxa (1.8% of all 571 taxa of rare plants); Aristolochia contorta (LC), Euryale ferox (VU), Melothrua japonica (LC), Utricularia pilosa (CR), Hydrocharis dubia (LC), Carex idzuroei (DD), Acorus calamus var. angustatus (LC), etc. Based on the list of endemic plants by the Korea National Arboretum, 10 taxa (3.0% of all 328 taxa of endemic plants); Salix pseudolasiogyne, Philadelphus incanus, Indigofera koreana, Lespedeza ${\times}$ maritima, Stewartia pseudocamellia, Weigela subsessilis, Carex okamotoi, etc. Based on the list of specific plants by floral region were total 43 taxa (4.0% of all 1,071 taxa of specific plants); 4 taxa (Euryale ferox, Hydrocharis dubia, Carex idzuroei, etc.) in class IV, 9 taxa (Ilex crenata, Acer palmatum, Stewartia pseudocamellia, Melothria japonica, Fatsia japonica, etc.) in class III, 3 taxa (Caltha palustris var. membranacea, Nymphoides indica, etc.) in class II, 26 taxa (Cyrtomium fortunei, Chloranthus japonicus, Quercus variabilis, Ulmus parvifolia, Aphananthe aspera, etc.) in class I. Based on the list of naturalized plants, 48 taxa (Rumex crispus, Chenopodium album var. album, Amaranthus patulus, Phytolacca american, Brassica juncea var. integrifolia, Potentilla paradoxa, Robinia pseudoacacia, Euphorbia maculata, Oenothera odorata, Cuscuta pentagona, Veronica persica, Plantago lanceolata, Diodia teres, Helianthus tuberosus, Dactylis glomerata, etc.), naturalization rate was 10.5% of all 456 taxa of vascular plants and urbanization index was 15.0% of all 321 taxa of naturalized plants. Ecosystem disturbing wild plants were 3 taxa (Rumex acetocella, Solanum carolinense, Ambrosia artemisiifolia).

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.5
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• pp.590-603
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• 2006

Size-and time-resolved aerosol samples were collected using an eight-stage Davis rotating unit for monitoring (DRUM) sampler from 23 March to 29 April 2001 at Gosan, Jeju Island, Korea, which is one of the super sites of Asia-Pacific Regional Aerosol Characterization Experiment(ACE-Asia). These samples were analyzed using synchrotron X-ray fluorescence for 3-hr average concentrations of 19 elements including Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, Rb, and Pb. The size-resolved data sets were then analyzed using the positive matrix factorization(PMF) technique to identify possible sources and estimate their contributions to particulate matter mass. PMF analysis uses the uncertainty of the measured data to provide an optimal weighting. Twelve sources were resolved in eight size ranges($0.09{\sim}12{\mu}m$) and included continental soil, local soil, sea salt, biomass/biofuel burning, coal combustion, oil combustion, municipal incineration, nonferrous metal source, ferrous metal source, gasoline vehicle, diesel vehicle, and volcanic emission. The PMF result of size-resolved source contributions showed that natural sources represented by local soil, sea salt, continental soil, and volcanic emission contributed about 79% to the predicted primary particulate matter(PM) mass in the coarse size range ($1.15{\sim}12{\mu}m$) while anthropogenic sources such as coal combustion and biomass/biofuel burning contributed about 58% in the fine size range($0.56{\sim}2.5{\mu}m$). The diesel vehicle source contributed mostly in ultra-fine size range($0.09{\sim}0.56{\mu}m$) and was responsible for about 56% of the primary PM mass.