Bloodstream Infections and Clinical Significance of Healthcare-associated Bacteremia: A Multicenter Surveillance Study in Korean Hospitals

Son, Jun Seong,Song, Jae-Hoon,Ko, Kwan Soo,Yeom, Joon Sup,Ki, Hyun Kyun,Kim, Shin-Woo,Chang, Hyun-Ha,Ryu, Seong Yeol,Kim, Yeon-Sook,Jung, Sook-In,Shin, Sang Yop,Oh, Hee Bok,Lee, Yeong Seon,Chung, Doo The Korean Academy of Medical Sciences 2010 JOURNAL OF KOREAN MEDICAL SCIENCE Vol.25 No.7

<P>Recent changes in healthcare systems have changed the epidemiologic paradigms in many infectious fields including bloodstream infection (BSI). We compared clinical characteristics of community-acquired (CA), hospital-acquired (HA), and healthcare-associated (HCA) BSI. We performed a prospective nationwide multicenter surveillance study from 9 university hospitals in Korea. Total 1,605 blood isolates were collected from 2006 to 2007, and 1,144 isolates were considered true pathogens. HA-BSI accounted for 48.8%, CA-BSI for 33.2%, and HCA-BSI for 18.0%. HA-BSI and HCA-BSI were more likely to have severe comorbidities. <I>Escherichia coli</I> was the most common isolate in CA-BSI (47.1%) and HCA-BSI (27.2%). In contrast, <I>Staphylococcus aureus</I> (15.2%), coagulase-negative <I>Staphylococcus</I> (15.1%) were the common isolates in HA-BSI. The rate of appropriate empiric antimicrobial therapy was the highest in CA-BSI (89.0%) followed by HCA-BSI (76.4%), and HA-BSI (75.0%). The 30-day mortality rate was the highest in HA-BSI (23.0%) followed by HCA-BSI (18.4%), and CA-BSI (10.2%). High Pitt score and inappropriate empirical antibiotic therapy were the independent risk factors for mortality by multivariate analysis. In conclusion, the present data suggest that clinical features, outcome, and microbiologic features of causative pathogens vary by origin of BSI. Especially, HCA-BSI shows unique clinical characteristics, which should be considered a distinct category for more appropriate antibiotic treatment.</P>

인버터 구동용 유도전동기 고정자 권선의 절연특성 연구

황돈하,김동희,이광식,정원영,김영훈,오승훈 영남대학교 공업기술연구소 1999 工業技術硏究所論文集 Vol.27 No.2

Inverters with high speed switching and advanced PWM techniques are widely used for variable speed applications. But some adverse effects on the stator winding insulation are reported due to excessive voltage stress, which results in the premature insulation breakdown. This is aggravated by the high switching speed of modem switching devices such as IGBT (Insulated Gate Bi-polar Transistor) with which the rate of rise in voltage (dv/dt) increases considerably. In this paper, the test results for evaluation on the stator winding insulation of 310V induction motors are presented. Also, the insulation characteristics are presented in order to analyze the insulation strength under high voltage due to high switching speed of IGBT PWM inverter. 26 induction motors of 6 types with different wires and insulation techniques are built and thoroughly tested. The maximum partial discharge (PD) magnitude (Qm) and the discharge inception voltage (DIV) are obtained by PD test. Under AC current test, the rate of change in AC current (ΔI) and the change in dissipation factor (Δtanδ) are measured. From the above test data, the effects due to different wires and insulation techniques on the insulation characteristics of low-voltage induction motors are compared and analyzed. The insulation technique to enhance the insulation strength is suggested from the test results.

초·중·고등학교 학생·학부모·일반교사의 보건교육 영역별 요구도와 보건교육

윤순녕,김영임,최정명,조희순,김영희,박영남,오경순,이분옥,조선녀,조소영,한선희,하영미 韓國學校保健學會 2005 韓國學校保健學會誌 Vol.18 No.1

Purpose: The purpose of this study was to identify the needs of health education in students, their parents and teachers in the elementary, middle and high schools and the current situation of health education class. Method: The subjects of this study were a total of 9450 persons including students, their parents and teachers from 279 schools throughout the country. They were selected through convenient sampling. Data were analyzed through x^(2)­test and ANOVA. Result: Students, their parents and teachers replied that 18 dimensions of health education class (DHEC) are necessary. The four DHEC - healthier life style, sex education, mental health and safety education - showed high educational needs in students, their parents, and teacher. High school students had higher educational need of 'symptom management for daily living' than elementary and middle school students. Students, their parents and teachers in elementary school had higher educational needs of 17 DHEC that those in middle and high school. The percentages of schools with health education class taught by health teachers were 99.2%, 75.5% and 66.0% respectively in elementary, middle and high schools. Health education was given mainly using physical education classes at elementary schools, and creative class hours at middle and high schools. In general, health education took 1-3 hours per week at elementary schools, and less than an hour at middle and high schools. Conclusion: Therefore, based on the results, systematic health education class should begin from elementary school to meet the need of health education in students, their parents and teachers, and further study should be made on the number of hours required and the amount of contents of 18 DHEC.

초·중·고등학교 학생, 학부모, 일반교사의 보건교육 요구

윤순녕,김영임,최정명,조희순,김영희,박영남,오경순,이분옥,조선녀,조소영,한선희,하영미 韓國學校保健學會 2004 韓國學校保健學會誌 Vol.17 No.2

Purpose : The purpose of this study was to identify needs of health education of the students, parents, general teachers, and health teacher of the elementary, middle, and high schools. Method : 279 schools of elementary, middle, and high school were sampled nonproportionally during the period from June 28 to July 26, 2004 . The data were collected by the questionnaire from 1,888 students, 1,876 parents, 1,695 general teachers, 279 health teachers. A frequency, % and χ2-test were used to analysis by SAS program. Result : 1. It showed that 98.1% of elementary school students, 92.3% of middle school students, 89.6% of high school students answered that they need health education. The most of students, parents, and general teachers had high interests in health education. 2. In the case of students, main causes of needs of health education was 'to prevent diseases or accidents''. But parents answered that it was 'to build up a healthier behavior'. General teachers answered that it was 'more effective systematic and continuous health education'. 3. Over 80% of students, parents, and general teachers about the question of who qualified person is to teach health education as a regular class responded that health teacher is available. Especially 93% of elementary school students answered like that. 4. The most of students, parents, and general teachers answered that health education in the classroom is favorable 1 to 2 hours per week. Conclusion : As results of the study , the majority of students, parents, general teachers agreed needs of health education. Therefore, on the basis of this study, systematic and continuous health education is necessary. Additionally the establishment of independent health subject is required certainly.

A numerical study on the buoyancy effect around slanted-pin fins mounted on a vertical plate (Part-I: Laminar natural convection)

Oh, Yeong Woong,Choi, Yoon Suk,Ha, Man Yeong,Min, June Kee Pergamon Press 2019 International journal of heat and mass transfer Vol. No.

<P><B>Abstract</B></P> <P>A numerical study on the natural convection heat transfer of slanted-pin fins mounted on a vertical wall has been conducted for the laminar flow regime. Assuming the air is the ideal gas, three-dimensional governing equations of flow and heat transfer was solved using the periodic boundary condition in the horizontal lateral direction with the SIMPLE algorithm. The effect of radiation heat transfer was considered using the discrete ordinate method based on the evidence of the code validation through a comparison with experimental data. The effects of the fin-inclination angle ranging from −45° to + 45° and the aspect ratio of the rectangular-fin pins for 0.25–4.0 were examined for a modified Rayleigh number range of 5.2 × 10<SUP>10</SUP>–1.3 × 10<SUP>10</SUP> under constant heat flux conditions. For the positively-inclined fins, the enhancement of the heat transfer performance on the heated plate and fin-side surface was captured, which is similar to previous forced convection studies. For negative inclination angles, however, it was observed that the penetration of cold air from the quiescent region affects the heat transfer coefficient distribution on the top side of the fins in the vertical fin interspacing. As a result, in the present calculation, the negatively-inclined fins showed the best heat-transfer performance under a natural convection condition. Details on the buoyant-flow and heat transfer characteristics, such as the distributions of the local- and average-heat transfer coefficient, are quantitatively summarized.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The aero-thermal performance of slanted-pins on a vertical wall are examined. </LI> <LI> The natural convection heat transfer is studied numerically. </LI> <LI> The Rayleigh number is varied in a laminar flow regime. </LI> <LI> The fin-inclination angle showing the best performance is captured. </LI> <LI> Differences from the forced convection result are assessed. </LI> </UL> </P>

A numerical study on the buoyancy effect around slanted-pin fins mounted on a vertical plate (Part-II: Laminar mixed convection)

Oh, Yeong Woong,Choi, Yoon Suk,Ha, Man Yeong,Min, June Kee Elsevier 2019 INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER - Vol.132 No.-

<P><B>Abstract</B></P> <P>This paper presents a numerical study on the mixed convection heat transfer of slanted-pin fins mounted on a vertical heated wall for the laminar flow regime, which is an extension of the authors’ accompanying study (Oh et al. 2018) on the natural convection. Using the ideal gas assumption for the air, three-dimensional governing equations for fluid flow and heat transfer were calculated by imposing a periodic boundary condition in the horizontal lateral direction with the SIMPLE algorithm. The discrete ordinate method was also included to calculate the effect of radiation. The effects of the fin-inclination angle were investigated in a modified Richardson number range of 500–2500 by varying the Reynolds number at a fixed Grashof number. It was found that as the forced convection increases, the fin-inclination angle showing the best heat transfer performance changes from negative to positive fin angles. The critical Richardson number for this transition and the corresponding flow and heat-transfer characteristics in the mixed convection regime are summarized.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The aero-thermal performance of slanted-pins on a vertical wall are examined. </LI> <LI> The mixed convection heat transfer is studied numerically. </LI> <LI> The modified Richardson number is varied in a laminar flow regime. </LI> <LI> The fin-inclination angle showing the best performance is captured. </LI> <LI> Differences from the forced- and natural- convection results are assessed. </LI> </UL> </P>

수직 평판에 설치된 경사 핀-휜의 혼합대류 열전달 특성에 대한 수치적 연구

오영웅(Yeong Woong Oh),최윤석(Yoon Suk Choi),하만영(Man Yeong Ha),민준기(June Kee Min) 대한기계학회 2018 대한기계학회 춘추학술대회 Vol.2018 No.12

The heat transfer of slanted-pin fins mounted on a vertical heated wall under laminar mixed convection condition has been investigated numerically, which is an extended study of the authors previous research on the natural convection [5]. Assuming the air is the ideal gas, three-dimensional governing equations of flow and heat transfer was solved using the periodic boundary condition in the horizontal lateral direction with the SIMPLE algorithm. The radiation heat transfer was calculated by using the discrete ordinate method to make sure the validation through a comparison with the experimental data. The effects of the fin-inclination angle were conducted in a modified Richardson number range of 500 - 2500 by varying the Reynolds number at a fixed Grashof number under constant heat flux conditions. As the forced convection increases, the advantageous fin-inclination angle having the best heat transfer capability became from negative to positive fin angles. The critical Richardson number showing this transition phenomena and corresponding characteristics of flow and heat-transfer are summarized.

Change of GI Symptom and Quality of Life in Renal Transplant Patients after Conversion from Mycophenolate Mofetil (MMF) to Enteric coated Mycophenolate (EC-MPS)

오하영 ( Ha Young Oh ),이삼열 ( Sam Yel Lee ),양철우 ( Chul Woo Yang ),김영훈 ( Yeong Hoon Kim ),한덕종 ( Duck Jong Han ),김연수 ( Yon Su Kim ),김명수 ( Myoung Soo Kim ),하경수 ( Kyoung Soo Ha ) 대한신장학회 2008 춘계학술대회 초록집 Vol.28 No.1

소독제 별 표면소독 효과 분석

오은비(Eun-Bee Oh),오윤교(Yun-Gyo Oh),백찬영(Chan-Yeong Baek),송진하(Jin-Ha Song),윤소희(So-Hee Yoon),오상환(Sang-Hwan Oh) 대한치과의료관리학회 2019 대한치과의료관리학회지 Vol.7 No.1

Some properties of a new D-π-A dye based on hydroxyl-methoxybenzene donor and isophorone acceptor moiety: Effects of anion, ethylamine and temperature

Oh, Byeong M.,Noh, Ha Lim,Gwon, Seon-Yeong,Park, Young Ki,Cho, Namchul,Lee, Woosung,Kim, Sung-Hoon,Kim, Jong H. Elsevier 2018 Dyes and pigments Vol.159 No.-

<P><B>Abstract</B></P> <P>Some sensing properties of a new D-π-A dye (dye<B>3</B>) based on hydroxyl-methoxybenzene donor and isophorone acceptor moiety were investigated by using spectroscopic and electrical measurements. The effects of anion, ethylamine and temperature on the color/emission changes of dye<B>3</B> in solution and resistance changes in thin-film were evaluated and characterized. Dye<B>3</B> exhibited colorimetric and fluorometric changes in response to cyanide anion. The reversible colorimetric sensing mechanism of dye<B>3</B> to the cyanide, based on the complex formation by anion binding, was studied with the use of <SUP>1</SUP>H NMR analyses together with theoretical calculations. Then the interactions of dye<B>3</B> with three ethylamines (mono-, di-, and tri-ethylamine) were investigated. Dye<B>3</B> showed different degree of changes in UV/Vis absorption spectra when exposed to different ethylamines. From the kinetic studies based on the association constant calculation and theoretical calculations, we revealed that different interaction distance between dye<B>3</B> and ethylamines caused discrepancy in absorption spectrum changes. Finally, the effect of temperature on the electrical properties of dye<B>3</B> was explored. Dye<B>3</B> showed an increase or decrease in electrical resistance because of its semiconducting property. In this article, some unique properties of D-π-A-type dye<B>3</B> were systemically investigated, and these properties suggest the potential applicability of dye<B>3</B> to the multi-stimuli (anion, volatile organic compounds (VOCs) and temperature) responsible smart chemosensors.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Unique spectral and electrical properties of a new D-π-A dye (dye<B>3</B>) were investigated. </LI> <LI> Dye<B>3</B> showed discernable and reversible color changes in response to the cyanide ion. </LI> <LI> Dye<B>3</B> showed spectral changes in response to the volatile organic compounds (VOCs), ethylamine. </LI> <LI> Dye<B>3</B> showed reversible electrical resistance changes in response to the applied temperatures. </LI> <LI> Mechanism of these unique property was studied by spectral analyses and theoretical calculations. </LI> </UL> </P>