김치유래 젖산균의 균체지방산 분석을 이용한 분류학적 연구

이정숙,정민철,김우식,이근철,김홍중,박찬선,이헌주,주윤정,이근종,안종석,박완,박용하,민태익 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.2

표준균주를 포함한 230여개의 김치유래 젖산균에 대한 균체지방산(FAMEs)을 분석하였다. FAMEs profiles는 Euclidian Distance 17.5에 의해 7개의 Major Cluster와 1개의 Single Cluster로 나뉘어졌다. 이중 A, B, C 및 Cluster는 Leuconostoc속으로 분석되어졌고, F는 Lactobacillus속으로 분석되어졌다. 그리고 E와 G cluster는 두개의 Genus가 혼재되어 나타났으며 보충적인 연구가 필요하다. 앞으로 김치유래 젖산균의 균체지방산 분석결과를 기반으로 한 데이타베이스에 95가지 탄소원을 이용하는 수치분류학적 접근방법 및 Pyrolysis Mass Spectrometry 등의 화학적 분석 방법과 분자친화적 연구를 통한 종합적 분류정보 체계가 갖추어지면 젖산균의 신속, 정확한 동정 및 연구에 활발히 이용되어질 것이다. Two hundreds and thirty lactic acid bacteria, mostly isolated from Kimchi, including type strains were sued for analysis of cellular fatty acids. The 230 test strains were recoverd in 7 major and 1 single clusters defined a Euclidian distance of 17.5. These aggregate taxa were equivalent to the genus Leuconostoc (aggregate group A, B, C and D), and the genera Leuconostoc and Lactobacillus (aggregate group G). It is concluded as evident that FAMEs (Fatty Acid Methyl Esters) profile of cell can be used as a criterion in classification of lactic acid bacterial from kimchi. Additional comparative taxonomic studies need to be carried out on well chosen representative strains to determine the most appropriate methods of value.

여행업문화가 조직유효성에 미치는 영향에 관한 연구

이선희,이용근 문화관광연구학회 1999 문화관광연구 Vol.1 No.1

ABSTRACTAn Influence of Travel Agency's Culture on Organizational Effectiveness Sun-Hee Lee·Yong-Keun Lee The Effects of corporate culture on the organizational effectiveness and/or corporate competitiveness have been widely recognized and discussed among both the incumbent managerial and the academicians of economics and sociology in recent years. The purpose of this study is to review the functions of the corporate culture and to examine the factors of the corporate culture among the travel agencies.The present study starts with a conceptual review of the corporate culture. The characteristics of corporate culture is shaped usually with the two major elements; the styles of management and decision-making of the top managerial and the subculture of the employees. Each of the four components of Corporate culture is operationalized as follows; ① tough-guy, macho culture, ② work hard, play hard culture, ③ bet-your-company culture, ④ process culture. These four components of corporate culture become the independent variables while the recognition of environment becomes the dependent variables in the analytical model proposed in this paper. The recognition of environment such as danger and feed-back speed is divided into pre-IMF and post-IMF.Some results of the findings are as follows: First, before IMF, as the danger is recognized low and feed-back speed fast, the corporate culture is shown as work hard, play hard culture. Second, after IMF, as the danger is recognized high and feed-back speed fast, the corporate culture is shown as tough-guy, macho culture.

추황배(Pyrus pyrifolia Nakai cv. Chuhwangbae) 과피로부터 1종의 Sterol과 3종의 배당체 화합물의 단리·동정

이유건(Yu Geon Lee1),조정용(Jeong-Yong Cho),이현주(Hyun Joo Lee),이용현(Yong Hyun Lee),이상현(Sang-Hyun Lee),한태호(Tae-Ho Han),김월수(Wol-Soo Kim),박근형(Keun-Hyung Park),문제학(Jae-Hak Moon) 한국식품과학회 2013 한국식품과학회지 Vol.45 No.5

본 연구에서는 배의 유용성 증명을 위한 일환으로 배의 화학성분을 분자수준에서 밝히고자 하였다. 이에 배 과피 MeOH 추출물을 용매분획하여 얻은 EtOAc-산성 분획과 EtOAc-중성분획을 대상으로 Sephadex LH-20, silica gel, 그리고 ODS colmn chromatography와 HPLC를 이용하여 정제 및 단리하였다. 그 결과, EtOAc-산성 분획과 EtOAc-중성 분획으로부터 각각 2종씩의 화합물을 단리하였다. 단리된 화합물 1-4는 1H- 및 13C-NMR 분석을 통하여 각각 (S)-(+)-2-cis-abscisic acid O-β-D-glucopyranosyl ester (화합물 1), 1-[4-O-β-D-glucopyranosyl]phenyl ethanone(piceoside, 화합물 2), β-sitosterol (화합물 3), 그리고 β-sitosteryl 3-O-β-D-glucopyranoside (화합물 4)로 동정되었다. 단리된 3종의 배당체 화합물(화합물 1, 2, 4)들은 본 연구에 의해 배로부터 처음 동정되었으며, 화합물 3은 추황배로부터 처음 동정되었다. 본 연구결과가 배 함유 성분연구는 물론 배의 기능성 해명 연구에도 추후 중요한 기초자료로 활용되길 기대한다. We isolated and identified antioxidants from acidic and neutral ethyl acetate fractions of the peel of pear (Pyrus pyrifolia N. cv. Chuhwangbae). We isolated 4 compounds from the methanol extract, by using 3 different types of column chromatography (Sephadex LH-20, silica gel, and octadecylsilane) and preparative HPLC. We identified the isolated compounds as (S)-(+)-2-cis-abscisic acid O-β-D-glucopyranosyl ester (compound 1), 1-[4-O-β-D-glucopyranosyl]phenyl ethanone (picroside, compound 2), β-sitosterol (compound 3), and β-sitosteryl 3-O-β-D-glucopyranoside (compound 4) by nuclear magnetic resonance analysis. We are the first to report the identification of compounds 1, 2, and 4 from pear.

지난 2년간의 학회지 "신경정신의학" 심사 평가보고

김찬형,김세주,김도관,김성곤,박원명,송동호,박용천,이영문,오강섭,정영철,이상열,김주한,이동영,이헌정,함병주,김율리,김문두,김정진,이강욱,천근아,김재진,홍진표,홍승철 大韓神經精神醫學會 2007 신경정신의학 Vol.46 No.6

貿易契約上 買受人의 契約違反에 따른 賣渡人의 損害賠償請求

李鎔根 中央大學校 經營硏究所 1996 經營學論集 Vol.22 No.1

치아미백제에 의한 치과 수복재의 특성변화에 관한 연구

이용근 대한치과기재학회 1996 대한치과재료학회지 Vol.23 No.2

Tooth whiteners are used widely to recover the original color of tooth. There is no doubt these products work as whiteners, at least on mild to moderate stains, but the safety of these products are unclear. Abrasive agents in the tooth whitener remove attached stains on the tooth surface or bleaching agents in the tooth whitener change the organic material within the tooth. Free radicals released from tooth whiteners can change the surface properties including color of restorative materials or can accelerate the corrosion of dental appliances made of metal. In this experiment, the effect of tooth whitener application on the color and microhardness of seven esthetic restorative materials was determined in vitro. RMS, NWT and MTD were used as tooth whiteners and tooth paste(DTQ) was used as control. Specimens were made according to the manufacturer's instructions and were polished. Initial color and Vickers hardness were measured. The tooth whiteners and control agents were applied according to the manufacturers' instructions or clinically simulated procedures for eight weeks. Color difference was measured using Differential Colorimeter(Model TC-6FX, Denshoku Co. Japan), and microhardness was measured using microhardness tester (Mitsuzawa Seiki Co. Japan). The results of CIELAB L*, CIELAB ΔE* and Vickers hardness were analyzed. The results were as follows; 1. CIELAB L* values after tooth whitener application were changed significantly depending on three variables, those were material type, tooth whitener type and application period(p<0.01). Five kinds of materials showed the highest CIELAB L* values after RMT application, but the difference of values among the materials was small. 2. DTQ applied group showed the smallest color difference (CIELAB ΔE* value) after application for four or eight weeks, and NWT applied group showed the highest color difference during first four week period. MTD applied group showed the highest color difference during four to eight week period, and resultantly showed the highest color difference after eight week application. 3. Vickers hardness numbers were generally increased after whitener application. In the same material, the change ratios of VHNs were not different regardless of the applied agents, and VHNs of glass ionomers were increased significantly higher than those of composite resins.

알지네이트 인상재의 하중속도와 혼수비에 따른 압축특성의 변화

이용근 원광대학교 생체재료·매식연구소 1977 원광생체재료·매식 Vol.6 No.1

Information on viscoelastic properties of elastic impression materials are not sufficiently understood by the practitioners. In literature, this is referred to in general terms, and is stated that 'The removal of an impression from the mouth presents some problems that cell for special physical properties in an impression material' In this study, changes of elastic modulus, compressive strength and percent compression at maximum load of alginate impression materials were determined as the loading rate or powder-water ratio changed. And correlation between compressive mechanical properties and the loading rate or powder-water ratio was analyzed. Three kinds of alginate impression materials were studied, and the rate of loading was 10, 25, 50 or 100 mm/min. and the power-water ratio was from standard(100%) to 225% of standard. The results were as follows : 1. Brand of alginate impression materials, the loading rate and powder-water ratio significantly influenced on the elastic modulus, compressive strength and percent compression at maximum load(p<0.05). 2. Elastic modulus and compressive strength of alginate impression materials generally increased as the loading rate increased, and in some cases those properties increased significantly in higher rate of loading(p<0.05). 3. There was a statistically correlation between the loading rate and each of the three measured mechanical properties(p<0.01), and the correlation coefficient was in the range of 0.1384∼0.1653. 4. There was a statistically significant correlation between the powder-water ratio and each of the three measured mechanical properties(p<0.01), and the correlation coefficient was in the range of 0.5953∼0.6736.

치과교정용 탄선의 전기화학적 부식평가

이용근,김철위 大韓齒科器材學會 1994 대한치과재료학회지 Vol.21 No.2

The corrosion of dental orthodontic appliances can have serious clinical implications ranging from loss of dimension to stress corrosion failure of the appliances. The production of possible toxic corrosion products and their absorption by the surrounding tissue is undesirable. The study on the toxicity of corrosion products is carried out actively nowadays. And it is the standard practice of biocompatibility test that the elucidation of reaction mechanism between wire and electrolyte using electrochemical corrosion test. In this study, five kinds of stainless steel orthodontic wires, four kinds of cobalt-chromium orthodontic wires and two kinds of nickel-titanium wires were studied using electrochemical method. The results were as follows : 1. The corrosion potentials of orthodontic wires did not change much after altering the measuring condition, but the zero current potentials of those had great variation after altering the measuring condition. 2. Stainless steel orthodontic wires showed apparent passivation within the oral potential range. In the rescan procedure, the current density was reduced than the first scan and the transformation of oxide layer was observed around -100 mV(SCE) in some wires. 3. Cobalt-chromium orthodontic wires showed passivation starting from -800∼-700mV(SCE), and maintained upto +700mV(SCE). In the rescan procedure, the current density was reduced apparently than the first scan and similar potentiodynamic polarization curve as first scan was obtained after rescan procedure. 4. Nickel-titanium orthodontic wire showed increase of current density in the range of -100∼+100 mV(SCE) and showed passivation in the range of +200∼+800 mV(SCE). In the rescan procedure, the current density was higher than in the first scan in some potential range.

Micronucleus test를 이용한 수종 결합용레진과 상아질결합제의 돌연변이 유발에 관한 연구

이용근,전혜림,김철위,윤숙진 大韓齒科器材學會 1992 대한치과재료학회지 Vol.19 No.1

The purpose of this study was to evaluate the mutagenicity of the bonding resins of dental composites and the dentin bonding agents. Eight bonding resins, six dentin bonding agents and distilled water (negative control) were administered orally and cyclophosphamide (positive control) was administered intraperitoneally to the mice. The mice were killed by cervical dislocation at 24 hours after administration and the femurs were removed and dissected. The bone marrow cells were collected and smeared on glass slides and stained with haematoxylin-eosin staining method and were observed with light microscope(X450). The following results can be drawn: 1. The bonding resins of dental composites and the dentin bonding agents were tested in this study seemed to be non-mutagenic. 2. The numbers of micronucleated polychromatic erythrocytes were similar both in the bonding resins of dental composites and the dentin bonding agents. 3. In the case of some products(AP, SC' and AA), the number of micronucleated polychromatic erythrocs was high beyond other products.

치과용 시멘트의 열확산도 및 열차단 효과에 관한 연구

이용근,김철위 대한치과기재학회 1987 대한치과재료학회지 Vol.14 No.1

The purpose of this study was to measure the thermal diffusivity of dental cements commercially available in Korea and their thermal insulating effect. and the temperature rise in the pulp chamber simulated to the natural dentition in the mouth. Twenty three kinds of dental cements were used in this study. Seven of the dental cements were zinc phosphate cements, seven of them were polycarboxylate cements, four of them were glass ionomer cements and miscellaneous cements were four kind. The thermal diffusivity of each cements was measured after 1 and 24 hours after the start of mixing and compared with each other group. The temperature rise in the pulp chamber was measured through two discs of 0.5mm dentin and 0.9mm or 1.5mm cement disc by spraying hot water(55℃). From the experiment the following results were obtained: 1. The thermal diffusivity of dental glass ionomer cements was less than that of dental zinc phosphate cements and polycarboxylate cements. 2. The thermal diffusivity of dental zinc phosphate cements and polycarboxylate cements measured after 24 hours was more than that of 1 hour. 3. The thermal diffusivity of dental glass ionomer cements measured after 24 hours was less than that of 1 hour. 4. The thermal insulating effect of dental zinc phosphate cements and polycarboxylate cements was proportional to the thermal diffusivity in the experimental duration.