복합레진 표면의 연마방법에 따른 표면조도

민정범,조공철,조영곤 대한치과보존학회 2007 Restorative Dentistry & Endodontics Vol.32 No.2

본 연구는 복합레진의 종류와 연마방법, 복합레진 연마 후 레진전색제의 적용이 복합레진의 표면조도에 미치는 영향을 알아보기 위하여 복합레진의 표면조도 측정과 FE-SEM 관찰을 통하여 상호 비교하였다. 미세입자형과 nanofill 복합레진을 이용하여 8×3×2 mm의 시편을 각각 100개씩 제작하였고, 연마방법과 레진전색제의 적용 유무에 따라 20개의 군으로 분류하였다. 복합레진의 종류에 따라 Micronew를 사용한 군은 M군, Filtek Supreme을 사용한 군은 S군으로 분류한 후, 연마방법에 따라 M1군과 S1군은 polyester strip만을 사용한 군, M2군 와 S2군은 Sof-Lex disc를 사용한 군, M3군과 S3군은 Enhance disc와 polishing paste를 사용한 군, M4군과 S4군은 Astropol disc를 사용한 군, M5군과 S5군은 carbide finishing bur를 사용한 군으로 다시 분류하였다. 또한 연마 후 Biscover 레진전색제를 적용한 군은 연마방법에 따른 각 군에 B를 추가하여 M1B군-M5B군 및 S1B군-S5B군으로 분류하였다. 제작된 모든 시편은 표면조도의 측정과 주사전자 현미경 관찰을 시행하기 전에 실온의 증류수에서 24시간 동안 보관 하였다. 표면조도측정기를 사용하여 각 시편의 상면과 하면 모두에서 각각 5회씩 측정하여 평균 표면조도 값을 산출하여 통계적으로 분석하였으며, 각 군에서 대표적인 시편 1개를 선택하여 FE-SEM에서 관찰하여 다음과 같은 결과를 얻었다. 1. 복합레진의 표면조도 값은 polyester strip에 의해 형성된 모든 군에서 가장 낮게 나타났고, 레진전색제를 적용한 S군을 제외한 다른 모든 군에서 finishing bur로 연마한 군이 가장 높게 나타났다 (p < 0.05). FE-SEM 관찰에서 레진전색제를 적용하기 전의 표면은 polyester strip을 사용한 M1군과 S1군이 가장 평활한 표면을 나타냈고, finishing bur를 사용한 M5군과 S5군은 필러의 탈락에 의해 형성된 여러 개의 기포와 함께 울퉁불퉁한 표면을 보였다. 2. 복합레진의 종류에 따른 표면조도는 레진전색제를 적용하기 전에는 통계학적으로 차이를 나타내지 않았으나, 레진전색제를 적용한 후에는 Micronew가 Filtek Supreme보다 평활한 표면을 나타내었다 (p < 0.05). 3. 레진전색제를 적용하기 전에는 복합레진의 종류와 연마방법에 따른 표면조도 간에 상호 연관성이 있었으나, 레진전색제를 적용한 후에는 복합레진의 종류와 연마방법 간에 상호 연관성이 없었다. FE-SEM 관찰에서 레진전색제를 적용한 후의 표면은 모든 군에서 대체적으로 평활한 표면을 나타내었다. 4. 동일한 복합레진과 연마방법으로 처리된 군에서 레진전색제 적용 전과 후의 표면조도 값은 M1B군이 M1군보다, S1B군이 S1군보다 통계학적으로 높게 나타났으며, M4B군과 M5B군은 각각 M4군과 M5군 보다, 그리고 S5B군은 S5군 보다 통계학적으로 낮게 나타났다 (p < 0.05). 본 연구를 종합하여 보면, 복합레진의 종류에 따라 표면조도의 순서는 다르게 나타났고, polyester strip 하에서 복합레진이 중합된 경우 가장 낮은 표면조도 값과 평활한 표면을 제공하였으며 전반적으로 finishing bur는 가장 높은 Ra 값과 거친 표면을 제공하였다. Enhance, Astropol, carbide finishing bur로 연마한 표면은 레진전색제의 사용으로 평활한 표면을 얻을 수 있었지만, polyester strip과 Sof-Lex disc로 얻어진 표면은 레진전색제의 사용으로 표면조도의 개선이 이루어지지 않았다. The purpose of this study was to evaluate the difference of surface roughness of composite resin according to composite resin type, polishing methods, and use of resin sealant. Two hundred rectangular specimens, sized 8 × 3 × 2 mm, were made of Micro-new (Bisco, Inc., Schaumburg, IL, U.S.A) and Filtek Supreme (3M ESPE Dental Products, St. Paul, MN, U.S.A.), and divided into two groups; Micronew-M group, Filtek Supreme-S group. Specimens for each composite group were subdivided into five groups by finishing and polishing instruments used; M1 & S1 (polyester strip), M2 & S2 (Sof-Lex disc), M3 & S3 (Enhance disc and polishing paste), M4 & S4 (Astropol), and M5 & S5 (finishing bur). Polished groups were added letter B after the application of resin surface sealant (Biscover), eg, M1B and S1B. After specimens were stored with distilled water for 24 hr, average surface roughness (Ra) was taken using a surface roughness tester. Representative specimens of each group were examined by FE-SEM (S-4700: Hitachi High Technologies Co., Tokyo, Japan). The data were analysed using paired t-test, ANOVA and Duncan's tests at the 0.05 probability level. The results of this study were as follows; 1. The lowest Ra was achieved in all groups using polyester strip and the highest Ra was achieved in M5, S5 and M5B groups using finishing bur. On FE-SEM, M1 and S1 groups provided the smoothest surfaces, M5 and S5 groups were presented the roughest surfaces and voids by debonding of filler on the polished specimens. 2. There was no significant difference in Ra between Micronew and Filtek Supreme before the application of resin sealant, but Micronew was smoother than Filek Supreme after the application of resin sealant. 3. There was significant corelation between Ra of type of composite resin and polishing methods before the application of resin sealant (p = 0.000), but no significant interaction between them after the application of resin sealant. On FE-SEM, most of composite resin surfaces were smooth after the application of resin sealant on the polished specimens. 4. Compared with before and after the application of resin sealant in group treated in the same composite and polishing methods, Ra of M4B and M5B was statistically lower than that of M4 and M5, and S5B was lower than that of S5, respectively (p < 0.05). In conclusion, surface roughness by polishing instruments was different according to type of composite resin. Overall, polyester strip produced the smoothest surface, but finishing bur produced the roughest surface. Application of resin sealant provided the smooth surfaces in specimens polished with Enhance, Astropol and finishing bur, but not provided them in specimens polished with Sof-Lex disc.

증발 표면적 증대를 위한 수적 분리기 특성에 관한 연구

모종근,공태우,이광영,정효민,정한식,서정세 경상대학교 해양산업연구소 2002 해양산업연구소보 Vol.15 No.-

The purpose of this research is to obtain the characteristics of water-vapor separator for improving the evaporative surface. The experimental system is constituted with water vapor generator, vapor storage tank, laser source for visualization and camera for photography. The efficiency of water-vapor separator can be varied by the kinds of the inside materials. Thus, in this report, we introduced the three kinds of materials with wire scrap, wire brush and sponge. As the experimental results, the wire brush was showed the best efficiency with 185 g/hr.

김치 관련 연구문헌의 분류분석 및 김치연구의 동향 (Ⅲ)

최홍식,김재이,민병태,전정태,공연희,홍정진,김나영 부산대학교 김치연구소 2002 김치의 과학과 기술 Vol.8 No.-

About 200 research papers and patents on kimchi(Korean fermented vegetable food) published In the years of 1997-2001 were collected and analyzed for the classification and review. This article covers the classified topics on the natures and kinds of raw materials, fermentation and related microorganisms, processing / preservation, kimchi packaging, biochemical changes, enzymes, quality, food chemistry, functional klmchi, general consideration on kimchi, and also some research nerds In the future.

STS에 대한 고등학생들의 견해에 관한 평가도구 개발

임재항,강순민,공영태,최병순,남정희 한국과학교육학회 2004 한국과학교육학회지 Vol.24 No.6

이 연구의 목적은 STS에 대해서 우리 나라 고등학생들이 가지는 견해를 알아보기 위한 평가도구인 HS-VOSTS(Korean students' views on STS)를 개발하는 것이다. HS-VOSIS문항을 개발하기 위해서 다음과 같은 연구과 정을 수행하였다. 우선, 문헌과 선행 연구 고찰을 통해 4가지 범주의 10가지 하위 범주와 관련하여 23개의 논제를 포함하는 STS 범주 체계를 설정하였다. STS 범주 체계는 정의ㆍ과학의 외적 사회학ㆍ과학의 내적 사회학ㆍ인식론의 네 가지의 커다란 범주로 구성되어 있다. 다음은 91f 범주 체계를 기초로 4단계에 걸쳐 문항을 개발하였다. 1단계에서는 각 논제에 대한 짝진술문을 기초로 학생진술 문항지를 작성하여 772명의 고등학생들(16.3세)에게 투입하였다. 2단계에서는 짝진술문 중 하나를 제거하여 문항의 진술문으로 하고, 분류된 공통견해를 답지로 하여 1차 다지선다형 문항지를 구성하였다 3단계에서는 고등학생 28명(16.5세)을 대상으로 반구조화 면담을 실시하여 그 결과 분석을 통해 2차 다지선다형 문항지를 구성하였다. 4단계에서는 2차 다지선다형 문항지를 고등학생 306명에게 적용하여 낮은 반응비율을 보인 답지들을 제거하여 최종 검사도구를 완성하였다. HS-VOSTS는 학생들의 STS에 대한 신념 및 견해를 알아볼 수 있는 유용한 도구로서, 그 결과는 교사뿐만 아니라 교육과정 개발자, 교과서 저자, 교육정책 입안자들에게 많은 시사점을 줄 수 있을 것이라 생각한다. The purpose of this study was to develop HS-VOSTS(High School Students' Views On Science-Technology-Society), which is an instrument that monitors high school students' views on STS. For this study, 23 multiple-choice items were developed on four categories. First, a categorial scheme was constructed. The categorial scheme was based on many instruments that evaluate students' understanding on STS, literature review, and STS learning goal that many researchers had asserted. Second, the multiple-choice items were developed. The development of the items was carried out through four steps. In the first step, some pairs of statement on each subordinate category were formed. Next, the student statement questionaries which were based on the pairs of statement were responded by 772 students. In the second step, the response written by the students were analyzed to common viewpoints and the first multiple-choice items were constructed. In the third step, the semistructured interview with 28 high school students was implemented and the second multiple-choice items were constructed. In the fourth step, the final version of the instrument was developed through the analysis of the students' response on the second multiple-choice items. HS-VOSTS is an useful instrument for monitoring students' beliefs and viewpoints on STS topics. The results of the students' responses to HS-VOSTS items reflect the students' own thoughts directly. These results will give some implications for the curriculum developers, the authors of text books and the educational policy makers as well as the teachers.

항정신병약물을 처음으로 사용하는 초발 정신증 환자에서 나타나는 체중 및 대사성 지표의 변화 : 후향적 연구

김우진,심주철,공보금,강제욱,문정준,김정은,김민걸,박민경,김성진,김현정,정도운 대한생물치료정신의학회 2011 생물치료정신의학 Vol.17 No.2

Objectives:This study was to identify weight & metabolic changes in first-episode psychotic patients with antipsychotics use and investigate the differences of weight & metabolic changes between first-episode psychotic patients and controls with antipsychotics use. Method:In this retrospective study, twenty eight first-episode psychotic patients and twenty eight controls with schizophrenia, schizoaffective or bipolar disorder defined by DSM-IV criteria were included. Information about demographic and clinical characteristics of the subjects was gathered from the medical records. Also body weight, sBP, dBP, fasting glucose, lipid profile and WBC count were evaluated before and after antipsychotics use. Rogistic regression was conducted to assess factors associated with weight gain. Results:First-episode psychotic patients showed more weight and BMI changes than controls after antipsychotics use, and these changes continue over 12 months. On the other hand, there were no significant factors associated with weight gain. Conclusion:The results of present study suggest that antispychotics is one of the major causes inducing weight gain of psychotic patients and antipsychotics-induced weight gain is more vulnerable to drug-naive first-episode psychotic patients.

한국인 직무 스트레스 측정도구의 개발 및 표준화

장세진,고상백,강동묵,김성아,강명근,이철갑,정진주,조정진,손미아,채창호,김정원,김정일,김형수,노상철,박재범,우종민,김수영,김정연,하미나,박정선,이경용,김형렬,공정옥,김인아,김정수,박준호,현숙정,손동국 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.4

Background and Purposes: Over the past three decades, numerous studies performed in Korea have reported that job stress is a determinant risk factor for chronic diseases and work disability. Every society has its own culture and occupational climate particular to their organizations, and hence experiences different occupational stress. An occupational stress measurement tool therefore needs to be developed to estimate it objectively. The purpose of this study is to develop and standardize the Korean Occupational Stress Scale (KOSS) which is considered to be unique and specific occupational stressors in Korean employees. Subjects and Methods: Data were obtained from the National Study for Development and Standardization of Occupational Stress (NSDSOS Project: 2002-2004). A total of 12,631 employees from a nationwide sample proportional to the Korean Standard Industrial Classification and the Korean Standard Occupational Classification were administered. The KOSS was developed for 2 years (2002-2004). In the first year, we collected 255 items from the most popular job stress measurement tools such as JCQ, ERI, NIOSH and OSI, and 44 items derived from the a qualitative study (depth interview). Forty-three items of KOSS, in the second year, were retained for use in the final version of the KOSS by using Delphi and factor analysis. Items were scored using conventional 1-2-3-4 Likert scores for the response categories. Results: We developed eight subscales by using factor analysis and validation process: physical environment (3 items), job demand (8 items), insufficient job control (5 items), interpersonal conflict (4 items), job insecurity (6 items), organizational system (7 items), lack of reward (6 items), and occupational climate (4 items). Together they explained 50.0% of total variance. Internal consistency alpha scores were ranged from 0.51 to 0.82. Twenty-four items of the short form of the KOSS (KOSS-SF) were also developed to estimate job stress in the work setting. Because the levels of the subscales of occupational stress were gender dependent, gender-specific standard norms for both the 43-item full version and the 24-item short form using a quartile for the subscales of KOSS were presented. Conclusion: The results of this study suggest that KOSS might be an appropriate measurement scale to estimate occupational stress of Korean employees. Further and more detailed study needs to be conducted to improve the validity of this scale.

Desflurane이 흰쥐 Isolated Heart의 수축기능에 미치는 영향

최영석,이미경,윤석민,임상호,공명훈,정유성 대한마취과학회 1998 Korean Journal of Anesthesiology Vol.35 No.5

Background : Desflurane, a fluorinated methyl-ethyl ether, has some advantageous properties including low blood solubility, stability in soda lime, and resistance to biodegradation. Desflurane in vivo has demonstrated myocardial depressant property. The purpose of this study was to test the direct effects of desflurane on myocardial contractile function and coronary flow in the isolated heart. Methods : Twelve isolated rat hearts were continuously perfused with modified Krebs solution containing 6, 9 and 12 vol% of desflurane for 10 min at each concentration. Systolic left ventricular pressure and rate of change of ventricular pressure (dp/dt) were measured. Heart rate and coronary flow were also measured. To differentiate direct vasodilatory effect of desflurane from an indirect metabolic effect due to autoregulation of coronary flow, oxygen delivery, myocardial oxygen consumption and percent oxygen extraction were calculated. Results : Heart rate (control 266 22 beats/min) decreased to 250 23 beats/min at 6 vol%, 236 26 beats/min at 9 vol% and 223 22 beats/min at 12 vol% of desflurane. Systolic left ventricular pressure and dp/dt decreased in a concentration-dependent manner. In spite of decrement of myocardial oxygen consumption, coronary flow (control 12.0 1.2 ml/min) increased to 12.8 1.6 ml/min at 6 vol%, 12.9 1.6 ml/min at 9 vol% and 13.7 1.4 ml/min at 12 vol% of desflurane. Oxygen delivery increased proportionally with coronary flow. Percent oxygen extraction decreased in a concentration-dependent manner. Conclusion : These results suggest that desflurane has a direct myocardial depressing and coronary vasodilating effect in a concentration-dependent manner. (Korean J Anesthesiol 1998; 35: 825∼830)

Poster Session 1 : Signal Transduction ; TRANCE induces Leukocyte transendothelial migration through expression of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1)

( Jeong Ki Min ),( Eok Cheon Kim ),( Young Myeong Kim ),( In Koo Hwang ),( Moo Ho Won ),( Min Chul Kwon ),( Young Yun Kong ),( Jae Rang Rho ),( Young Guen Kwon ) 한국생화학분자생물학회 (구 한국생화학회) 2004 생화학분자생물학회 춘계학술발표논문집 Vol.2004 No.-

Effects of intestinal microflora on pharmacokinetics of baicalin and its main metabolites in normal and antibiotic-treated mice

KIM Jin-Sung,KONG Min-Jeong,OH Do-Gyeong,SEO Young-Min,KANG Mi-Jeong,JEONG Tae-Cheon 大韓藥學會 2012 大韓藥學會 總會 및 學術大會 Vol.2012 No.1

Poster Session 3 : Signal Transduction ; TRANCE induces expression of intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) through TRAFs and Ca(2+)-dependent nuclear factor-kB activation in endothelial cells

( Jeong Ki Min ),( Sam Kyou Choi ),( Eok Cheon Kim ),( Yoon Ee Huh ),( Min Chul Kwon ),( Young Myoung Kim ),( Jae Rang Rho ),( Young Yun Kong ),( Young Guen Kwon ) 한국생화학분자생물학회 (구 한국생화학회) 2003 생화학분자생물학회 춘계학술발표논문집 Vol.2003 No.-