액정의 윤활제로서의 응용에 관한 연구

민지홍,임윤철 연세대학교 산업기술연구소 1991 논문집 Vol.23 No.1

The velocity and pressure field are analyzed numerically for the thin wedge type liquid crystal film. Galerkin's weighted residual method is employed to solve momentum and continuity equations. Two of the characteristics of liquid crystal, permeability and splay effect, are treated in terms of body force and are investigated as well as the effect of the dislocations of layered crystal. A plane slider bearing is chosen to evaluate the load characteristics when liquid crystal is applied as a lubricant. The bearing load is increased compared to the conventional hydrodynamic lubrication theory. Numerical results are obtained up to the dimensionless permeability 0.5 due to the numerical instability.

볼리비아 로즈목에 의한 다형홍반 양상을 보인 직업성 알레르기 접촉피부염 증례

신주연,홍윤철,임종한,박신구,이지나,김환철 大韓産業醫學會 2004 대한직업환경의학회지 Vol.16 No.2

배경 : 로즈목(rosewoods) 중 볼리비아 로즈목(Machaerium Scleroxyon)은 강력한 감작물질을 함유하고 있어서 외국에서는 이로 인한 자극 또는 알레르기 접촉피부염의 발생이 증가하고 있음에도 불구하고 지금까지 우리나라에서는 볼리비아 로즈목을 비롯한 수입목재에 의한 직업성 피부질환의 보고가 부족하였고, 이에 저자들이 볼리비아 로즈목에 의한 다형홍반 양상을 보인 직업성 알레르기 접촉피부염의 증례를 경험하였기에 보고하고자 한다. 증례 : 49세 남자로서 여러 가지 수입목재를 절단하고, 다듬는 작업을 하다가 소양감을 동반한 홍반성의 피부 증상이 발현되었고, 전신으로 증상부위가 확대되어 2주 동안 병원 입원 치료를 하게 되었으며, 이후 본원 산업의학과에서 피부첩포 검사 후 최종적으로 볼리비아 로즈목에 의한 알레르기 접촉피부염으로 확진되었다. 결론 : 수입목재들로 인한 직업성 피부질환 발생에 대한 광범위한 실테 조사가 필요하며, 이를 토대로 작업장에서의 직업성 피부질환의 발생을 감소시키기 위한 다각적인 예방, 관리 대책의 수립이 필요하다. Background: Woods are capable of causing allergic or irritant contact dermatitis which typically occurs on exposed areas. Because Bolivian rosewood exclusively contains the strong sensitizer R-3,4-dimethoxdalbergione, an increasing number of cases of initant and allergic contact dermatitis has been reported. Case report: A 49-year-old, male, wood worker, who handled a variety of woods, developed allergic contact dermatitis. A patch test confirmed a positive reaction to one of the exotic woods, Bolivian rosewood. Allergens found in Bolivian rosewood caused this patient's dermatitis, which cleared when he avoided &is wood. Conclusion: Exotic woods such as Bolivian rosewood can induce occupaiional contact dermatitis. Measures to lower the incidence of work-related dermatitis are needed in the workplace. Especially, when cutting or sanding woods, workers should wear proper personal protection.

혈중 감마지티피 상승의 임상적 의의

신주연,김용규,박신구,이지나,김환철,임종한,홍윤철 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.1

목적: 혈중 감마지티피는 주로 알코올 섭취와 간세포 손상의 지표로서 이용되어져 왔으나 최근에는 혈중 감마지티피가 체내의 산소성 스트레스를 민감하게 반영하는 지표이며, 혈중 감미지티피를 이용하여 만성질환의 발생을 조기에 예측할 수 있다는 주장들이 있다. 이에 본 연구에서는 일반 인구 집단을 대상으로 한 건강검진 자료를 분석하여 혈중 감마지티피의 상승에 영향을 미치는 요인들을 분석하고 혈중 감마지티피와 산소성 스트레스와의 관련성 및 임상적인 이용 가능성을 알아보고자 한다. 방법: 2001년부터 2003년까지 한 대학병원 산업의학과에서 건강검진을 실시한 15,546명을 대상으로 하였고 신체계측, 혈액검사 그리고 설문지의 정보를 분석하였다. 총 15,546명 중 남성은 9,660명 이었고 여성은 5,886명 이었다. 연령, 성별, 체질량지수, 흡연, 음주, 운동량 비타민 복용 여부에 따른 혈중 감마지티피의 평균을 분석하였고, 성별에 따른 다변량 분석을 실시하였다. 다변량 분석에는 연령, 체질량지수, 음주빈도, 흡연량, 혈색소, 이완기혈압, 공복시혈당, 총콜레스테롤, ALT를 포함하였다. 결과: 연구 대상자들의 혈중 감마지티피의 평균은 남성에서 평균(±2SD)이 47.51(±111.62)이었고, 여성에서는 19.09(±42.02) 으로서, 대체적으로 정상 범위에 있다고 보여 지나 개인차가 상당히 크다는 사실을 알 수 있었다. 다변량 분석의 결과에서는 혈중 감마지티피의 상승에 영향을 미치는 요인이 성별에 따라 다소 달랐으나 남녀 모두에게 연령, 음주빈도, 흡연량, 이완기혈압, 공복시혈당, 총콜레스테롤, ALT가 유의한 영향이 있음을 확인할 수 있었다. 그리고 다변량 로지스틱회귀분석의 결과에서 '임상적 비정상'을 예측함에 있어 혈중 감마지티피가 진단적 유용성이 있음을 확인하였다. 결론: 긴존에 일반적으로 알려져 있는 것처럼 혈중 감마지티피를 단순히 알코올 섭취와 간세포 손상의 지표로서만 볼 수 없으며, 성별, 연령, 흡연, 고지혈증, 당뇨, 고혈압 등 많은 다른 요인들에 의해서 영향을 받으며, 혈중 감마지티피를 산소성 스트레스를 반영하는 생물학적 지표로 해석할 수도 있다. 따라서 혈중 감마지티피의 상승을 임상적으로 해석할 때는 (비록 정상인 범위에 있다하더라도), 알코올 섭취나 간세포 손상 뿐 아니라 다른 여러 요인들을 함께 고려해야 한다. 더욱이 혈중 감미지티피의 상승을 만성질환 즉, 고혈압, 당뇨, 고지혈증 등의 발생을 조기에 발견할 수 있는 지표로서 임상영역이나 건강검진시 유용하게 활용할 수 있을 것이다. Objectives: Incresed gamma-glutamyltransferase (GGT) concentration has mainly been used as a biologic marker of alcohol drinking and liver diseases. However, some recent reports have suggested that serum GGT concentration may be an early biomarker of oxidative stress and associated with chronic diseases like hypertension, DM, hyperlipidemia, CHD, stroke etc. In this study, we analysed the factors associated with increased serum GGT level and evaluated the clinical application of serum GGT in predicting the risk of chronic diseases. Methods: The data were collected from 15,546 periodic health examinations, 9,660 males and 5,886 females, done at one university hospital from 2001 to 2003. We analysed self-questionnaire, physical examination and laboratory data. Statistical analyses(t-test, ANOVA, Pearson's correlation analysis, multiple regression analysis and logistic regression analysis) were done by SPSS for windows 10.0. Results: Mean serum GGT levels were quite different according to age, sex, BMI, smoking and alcohol drinking (all P-value <0.001), but were not different by regular vitamin intake or not (P-value = 0.117). There was significant correlation between serum GGT level and the variables (of age, BMI, blood pressure, Hb, fasting blood sugar, total cholesterol, AST and ALT) (all P-value <0.001). In sex-specific multiple regression analysis, increased serum GGT level was significantly associated with age, alcohol drinking, smoking, blood pressure, fasting blood sugar and ALT in males (all P-value <0.001), and with age, alcohol drinking, smoking, Hb, blood pressure, total cholesterol and ALT in females (all P-value <0.05). In sex-specific logistic regression analysis, increased serum GGT level was significantly associated with risk of 'clinical abnormalities'. This risk increased about 13-fold in males and 4.6-fold in females for serum GGT level over the third quatile, compared with under the first quartile. Conclusions: Serum GGT level is increased not only by alcohol drinking or liver diseases, but also by many other factors associated with chronic diseases and behavioral factors. Thus many factors should be considered in evaluating an increase in GGT level, even when within the upper normal range. Serum GGT level may be a predictor for the early development of chronic diseases.

관동맥 우회로술 중 경식도 심초음파도로 관찰한 도부타민 투여후와 우회로술후의 좌심실 국소벽운동

김희열,김종진,윤호중,유기동,박지원,이길환,노태호,채장성,김재형,홍순조,최규보 대한순환기학회 1997 Korean Circulation Journal Vol.27 No.8

Fetal Entrapment in the Myometrium Caused by Ectopic Implantation Post Myomectomy

( Jee-youn Hong ),( Yoomin Kim ),( Jung-sun Kim ),( Byung Kwan Park ),( Suk-joo Choi ),( Soo-young Oh ),( Jeong-won Lee ),( Cheong-rae Roh ) 대한주산의학회 2020 Perinatology Vol.31 No.4

Fetal entrapment in myometrial dehiscence after myomectomy has been rarely reported. A 38-year-old woman, gravida 4, parity 2, with suspected amniotic or adhesion band was referred to our hospital at 234/7 weeks. She had undergone open myomectomy and cesarean delivery twice. Ultrasonography revealed two separate compartments divided by a septum-like structure with a small orifice. Magnetic resonance imaging (MRI) finding suggested an ectopic implantation on the endometric and myometrial dehiscence. At 25 weeks, the thoracic cage and umbilical cord escaped through the orifice. Emergent cesarean delivery and subtotal hysterectomy were performed for the placental increta at the myometrial dehiscent site. In fetal entrapment in myometrial dehiscence, MRI is valuable for the assessment of the fetus and spatial arrangement in the uterine cavity.

A New Cultivar of Sedum spp. ‘Green Pang’ with Orange Colored Leaf Edge

Youn Hee Kim,Jae Hong Lee,Jae Hong Jung,Jee Young Lee,Sang Youn Sim,Su Yeon Lee,Hye Hyeong Kim 한국원예학회 2021 한국원예학회 학술발표요지 Vol.2021 No.5

Evaluation of the Early Onset Neonatal Sepsis according to Two Antenatal Group B Streptococcus Screening Methods: Risk-Based versus Universal Screening

( Jee Youn Hong ),( Soo Hyun Kim ),( Seon Mi Kim ),( Cheong A Yee ),( Suk-joo Choi ),( Soo-young Oh ),( Cheong-rae Roh ) 대한주산의학회 2019 Perinatology Vol.30 No.4

Objective: The standard antenatal screening method for Group B Streptococcus (GBS) has not been established yet. Therefore, many practitioners in South Korea offer GBS screening to all pregnant women without solid clinical evidence. The aim of this study was to compare the rates of early onset neonatal sepsis (EONS) according to two different antenatal GBS screening methods - risk-based versus universal screening. Methods: This is a retrospective cohort study from January 2014 to April 2017. The study period was divided into two 16-month periods: from January 2014 to April 2015 in which risk-based screening was performed (period 1), and from January 2016 to April 2017 in which universal screening was performed (period 2). We compared the rates of EONS caused by GBS and other bacterial species between the two periods. Results: 1,301 neonates from 1,293 deliveries and 924 neonates from 913 deliveries were enrolled in period 1 and period 2, respectively. Suspected or culture-proven EONS caused by any organisms were more frequently observed in period 2 (0.7% in period 1 vs. 1.8% in period 2, P=0.013). The causative organism was not confirmed by culture in most cases, except for GBS, Escherichia coli, and Enterococcus. Intrapartum administration of antibiotic prophylaxis (IAP) was more frequently performed in period 2 (10.9% in period 1 vs. 21.5% in period 2, P<0.001). Conclusion: In spite of the significant increase in IAP rate in the period 2, EONS rates did not decrease by the universal antenatal GBS screening method.

Routine use or non-use of antenatal magnesium sulfate exposure for neuroprotection and risk of necrotizing enterocolitis in preterm neonates

( Jee Youn Hong ),( Yoo-min Kim ),( Ji-hee Sung ),( Suk-joo Choi ),( Soo-young Oh ),( Cheong-rae Roh ) 대한산부인과학회 2018 대한산부인과학회 학술대회 Vol.104 No.-

Objective: We aimed to evaluate the effect of magnesium sulfate treatment on the risk of NEC by comparing the rate of NEC between the periods of routine use or non-use of antenatal magnesium sulfate treatment for neuroprotection in preterm deliveries less than 32 weeks of gestation. Methods: This is a retrospective cohort study of neonates who were born between 24+0 and 31+6 weeks of gestations from January 2012 to December 2016. The subjects were classified into three groups (period 1; from January 2012 to December 2013 when antenatal magnesium sulfate treatment for neuroprotection was not used, period 2; from January 2014 to March 2016 when the treatment was routinely used, period 3; from April 2016 to December 2016 when the treatment was abandoned due to its potential risk of NEC. The primary outcome was NEC and neonatal death from NEC. Results: A total of 598 neonates (270 in the period 1, 264 in the period 2, and 64 in the period 3) were included in this study. In the period 2, 160 (60.6%) neonates were exposed to antenatal magnesium sulfate, and among them 124 (77.5%) were used for neuroprotection. In the period 1 and 3, 44 (16.2%) and 9 (14.0%) neonates, respectively, were exposed to antenatal magnesium sulfate and most of them were used for tocolytics or prevention of eclampsia. The rate of NEC was not significantly different among the three periods (23.0% in the period 1, 18.2% in the period 2, and 23.4% in the period 3, P=0.346). The rates of severe NEC (grade II or III), neonatal death due to NEC, and overall neonatal death were not significantly different among the three periods. Conclusion: This study implicates that the change of antenatal magnesium sulfate treatment protocol in preterm neonates was not associated with increased risk of NEC and neonatal death due to NEC. However, further studies are needed to evaluate the long-term effect of this treatment protocol change.

DDT 잔류물분석을 위한 효과적인 면역흡착정제방법에 대한 연구

홍지연 ( Ji Youn Hong ),홍지은 ( Jee Eun Hong ),최명자 ( Myung Ja Choi ),김종현 ( Jong Hyun Kim ),박송자 ( Song Ja Park ) 한국환경분석학회 2003 환경분석과 독성보건 Vol.6 No.2

의복관여도에 따른 판매원 서비스 평가에 관한 연구

홍주연,정성지 동덕여자대학교 디자인연구소 2004 디자인포럼21 Vol.7 No.-

본 연구의 목적은 백화점 소비자들의 의복관여도 수준에 따른 집단들 간의 판매원 서비스 중요도와 만족도 및 품질평가의 차이를 알아보는데 있다. 측정도구로는 선행연구들을 토대로 연구자가 수정 · 보완한 설문지를 사용하였고, 응답자의 의복관여도에 관한 문항과 판매원 서비스 평가에 관한 문항으로 구성되었다. 조사대상은 서울 및 경기 지역에 거주하고 있는 20대에서 50대 이상까지 백화점 이용고객을 대상으로 총 500부를 배부하여 그 중 447부를 본 연구의 최종 분석자료에 이용하였다. 자료의 분석을 위해 빈도분석과 백분율, Cronbach's α계수, ANOVA(분산분석) 및 Duncan's test 등을 통계분석기법으로 사용하였다. 본 연구결과는 다음과 같다. 의복관여도 수준(고관여/중관여/저관여)에 따라 집단간 판매원 서비스 중요도에 있어 유의한 차이를 보였고, 고관여 집단이 중관여 집단에 비해 판매원 전문성과 태도를 중요하게 생각하는 것으로 나타났다. 또한, 판매원 전문성과 고객편의제공에 있어 유의한 차이를 보였고, 고관여 집단이 중 · 저관여 집단보다 더 만족하는 것으로 나타났다. 그러나 관여도 수준에 따른 집단간 판매원 서비스 품질 평가에는 유의한 차이가 없었다. The purpose of the study was to explore differences in importance and satisfaction of sales person's service and evaluations of service quality among the groups according to the levels of clothing involvement. As an instrument, the questionnaire was developed by the researchers. For the data analysis, frequency, Cronbach's α, paired t-test, ANOVA, and Duncan's test was used. The result of the study was that there were significant differences in importance and satisfaction of sales persons' service, and evaluation of service quality among groups according to levels of clothing involvement.