감쇠보정, 산란보정 및 해상도복원이 정량적 심근 SPECT의 관상동맥질환 진단성능에 미치는 효과

황경훈,이동수,팽진철,이명묵,정준기,이명철 대한핵의학회 2002 핵의학 분자영상 Vol.36 No.5

목적: 심근 SPECT 영상의 재구성 과정에 감쇠보정, 산란보정 및 해상도복원 시스템(ASCRR)이 적용되었을 때 관상동맥질환 진단의 진단능 변화를 정량적 심근 SPECT에서 조사하였다. 대상 및 방법: 관상동맥질환이 의심되는 환자 75명과 관상동맥질환 저위험군 20명의 환자에 대하여 휴식기 씨-201 / 부하기 Tc-99m-MIBI 게이트 심근 SPECT를 시행한후, ASCRR을 적용하여 적용 전후의 예민도 및 특이도와 정상검출율의 변화를 구하였다. 결과: ASCRR 적용 후, 전반적인 진단능에는 유의한 변화가 없었다. 혈관 영역 별로는 좌전하행동맥(LAD)이나 좌회전동백(LCX) 영역의 병변에서는 유의한 차이는 없었고, 우측관상동맥(RCA) 영역의 병변을 진단하는 데 있어서는 ASCRR의 적용 후 특이도는 유의하게 향상되었지만, 이와 더불어 예민도는 유의하게 감소되었다(모두 p<0.05). 정상검출율은 좌전하행동맥(LAD) 영역과 좌회전동맥(LCX) 영역에서는 ASCRR 적용 전후에 유의한 차이가 없었고 우측관상동맥(RCA) 영역에서만 유의한 증가를 보여, 전반적으로는 통계적으로 유의한 차이가 없었다. 결론: 심근 SPECT에서 감쇠보정 및 산란교정, 그리고 해상도복원시스템의 적용은 관상동맥질환의 진단에 있어서 우측관상동맥(RCA) 영역의 정상검출율 및 특이도는 증가시키지만, 전반적인 진단능은 향상시키지 못한다. Purpose: Sort tissue attenuation and scattering are major methodological limitations of myocardial perfusion SPECT. To overcome these limitations, algorithms for attenuation, scatter correction and resolution recovery(ASCRR) is being developed, while quantitative myocardial SPECT also become available. In this study, we investigated the efficacy of an ASCRR-corrected quantitative myocardial SPECT method for the diagnosis of coronary artery disease (CAD). Materials and Methods: Seventy-five patients (M:F=51:24, 61.0=8.9 years old suspected of CAD who underwent coronary angiography (CAG) within 7±12 days of SPECT(Group-I) and 20 subjects (M:F=10:10, age 40.6=9.4) with a low likelihood of coronary artery disease (Group-II) were enrolled. T1-201 rest dipyridamole-stress Tc-99m-MIBI gated myocardial SPECT was performed. ASCRR correction was performed using a Gd-153 line source and automatic software (Vantage-Pro; ADAC Labs, USA). Using a 20-segment model, segmental perfusion was automatically quantified on both the ASCRR-corrected and uncorrected images using an automatic quantifying software (AutoQUANT; ADAC LAbs.). Using these quantified values, CAD was diagnosed in each of the 3 coronary arterial territories. The diagnostic performance of ASCRR-corrected SPECT was compared with that of non-corrected SPECT. Results: Among the 75 patients of Group-I, 9 patients had normal CAG while the remaining 66 patients had 155 arterial lesions: 61 left anterior descending (LAD), 48 left circumflex (LCX) and 46 right coronary (RCA) arterial lesions. For the LAD and LCX lesions, there was no significant difference in diagnostic performance. In Group-II patients, the overall normalcy rate improved but this improvement was not statistically significant (p=0.07). However, for RCA lesions, specificity improved significantly but sensitivity worsened significantly with ASCRR correction (both p<0.05). Overall accuracy was the same. Conclusion: The ASCRR correction did not improve diagnostic performance significantly although the diagnostic specificity for RCA lesions improved on quantitative myocardial SPECT. The clinical application of the ASC-RR correction requires more discretion regarding cost and efficacy. (Korean J Nucl Med 2002;36:288-97)

척추 전방 전위증 환자의 자기공명 영상 소견에서 보이는 추체종판의 변화

안재성,이준규,황득수,이원석 충남대학교 의과대학 지역사회의학연구소 1997 충남의대잡지 Vol.24 No.2

We reviewed the 156 magnetic resonance of lumbar spine with spondylolisthesis in simple X-ray and analysed relationship of the type of spondylolisthesis with bone marrow change in lumbar MRI and low back pain, instability of lumbar spine and prognosis. The patients with no bone marrow change were excluded in our study. Bone marrow changes were classified into 3 types by Moddic methods. Type I is low signal in T1 image and high signal in T2 image, type Ⅱ is high signal in T1 image and isodense or slight increased signal in T2 and type 2Ⅲ is decreased signal in both T1 and T2 image. Displacement over 3㎜ in motion view is defined as instability. Pain was scored by JOA scoring system. 22(14.1%) of 156 patients had local bone marrow change of vertebral end-plate. Of 22 patients, levels of lesion were 28 levels. 14 levels were isthmic type, 6 levels were degenerative type and 8 levels were retrolisthesis, respectively. Isthmic type had type Ⅰ or Ⅲ In 8(57.1%) levels, instability in 7(50.0%) levels and significant pain(0 of 1 point) in 9(69.2%) patients. Degenerative or retrolisthesis had type Ⅱ in 10(71.4%) levels, instability in 1(7.1%) level and significant pain in 4(44.4%) patients. Unstable and more symptomatic type of spondylolisthesis was associated with type Ⅰ or Ⅲ change of bone marrow in MRIm and may be teated more aggressively. Type Ⅰ or Ⅲ of bone marrow change is associated with segmental instability and low back pain and has a poor prognosis, but type Ⅱ are present in more stable and chronic disease. We concluded that isthmic type was more associated with pain, instability and type Ⅰor Ⅲ change, while degenerative or retrolisthesis type were more stable and painful and associated with type Ⅱ change.

L1210 세포증식에 대한 Glycyrrhizin의 억제작용 기전

殷載淳,徐龍勳,權鎭,柳東和,吳贊鎬,蘇俊魯,全焄,黃甲洙 우석대학교 의약품개발연구소 1996 藥學硏究誌 Vol.1 No.-

The purpose of this research was to investigate the mechanism of inhibitory action of Glycyrrhizin(GZ) on the proliferation of mouse leukemia cell-line, L1210 cells. The cytotoxic activity was tested using a colorimetric tertrazolium assay(MTT assay), the apoptosis was tested using flow cytometry. Nitric oxide(NO) production form mouse peritoneal macrophage was tested using a Griess method and the phagocytosis of human polymorphonuclear cells was tested using a lucigenin chemiluminescence. GZ ingibited the proliferation of L1210, BALB/c 3T3 cells and mouse thymocytes at 50 ug/ml/ GZ did not affect nitric oxide production from mouse peritoneal macrophages in vitro, but ingibited nitric oxide production from lipopolysaccharide and y-interferon treated macrophages. Macrophages of GZ-administered mice accelerated NO production. The proliferation of L1210 cells apoptosis of L1210 cells were induced by co-culture with macrophage of GZ-administered mice. The apoptosis of L1210 cells were induced by co-culture with macrophage of GZ-administered mice. GZ increased the phagocytosis of human polymorphonuclear cells. These results suggest that GZ inhibit the proliferation of L1210 cells not only as a direct cytotoxic agent o tumor cells, but also by the enhancement of NO production and phagocytic activity.

("황제내경소문(黃帝內經素問)" 허사연구(虛詞硏究)

이재선,황우준,이시형,금경수,Lee, Jae-Sun,Hwang, Woo-June,Lee, Si-Hyung,Keum, Kyeong-Su 대한한의정보학회 2008 大韓韓醫情報學會誌 Vol.14 No.1

The elementary idea of 'function-words' in Classical Chinese originates from Han dynasty. But because of the pictographic nature the methodology for 'content words' had been applied to the study on 'function words', ane the conditions had not changed until modern times. In grammar functions of the function-word syntactical, morphological in unit sentence were studied in this using the method of quantitative analysis for all the function-words appeared in ${\ll}$Hwang je nae gyung-Somun${\gg}$. In the previous studies about function word, many data were collected and analyzed diachronically. But those studies failed to examine function-words closed in connection with synchronic study. Besides, in the explain about relevant function-words also, the case which was made centering around exegetic explain was most. And in the case to explain the function-words have in unit sentence also, the explain only about some function-words is made, but the analysis about concrete function to have in syntactical system is being handled negligently. This study stands not only on the background df the traditional studies but also on the basis of the western grammar and linguistics, especially the descriptive grammar and linguistics, especially the descriptive grammar. ${\ll}$Hwang je nae gyung-Somun${\gg}$ is collect and recorded the mythology and special contents related to Daoism in the side of contents as what was written on the basis of the historical consciousness of individual in contents regardless of compilation system. The purpose of this study is to clarify how the role and function of fuction-words are being made in the composition of unit sentence which appeard in ${\ll}$Hwang je nae gyung-Somun${\gg}$ through synchronic grammar system.

Prediction of VLE for aqueous blended amines using VLE models of single amines

Hwang, Sung June,Kim, Huiyong,Lee, Kwang Soon Elsevier 2016 International journal of greenhouse gas control Vol.49 No.-

<P><B>Abstract</B></P> <P>The possibility of the vapor-liquid equilibrium (VLE) prediction of aqueous blended amines using Kent-Eisenberg (KE) VLE models of single amines has been investigated in this study. The VLE data of five different types of single amine and seven types of aqueous blended amine as mixtures of the selected single amines were collected first. The VLE of the single amines was fit to the KE models, and the VLE of the aqueous blended amines was predicted using the KE models of single amines without introducing any interaction terms between the amines. As a result, it was found that the VLE of the aqueous blended amines could be satisfactorily predicted using only the VLE models of single amines. Finally, VLE prediction ability as a function of temperature and the possible uses of the proposed method in the development of new aqueous blended amines were discussed.</P> <P><B>Highlights</B></P> <P> <UL> <LI> VLE of single amines are satisfactorily reproduced by the Kent-Eisenberg model. </LI> <LI> VLE of blended amines can be predicted by VLE models of single amines without additional terms. </LI> <LI> The proposed model can be used effectively in the development of blended amine solvents. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Multilevel non-volatile data storage utilizing common current hysteresis of networked single walled carbon nanotubes

Hwang, Ihn,Wang, Wei,Hwang, Sun Kak,Cho, Sung Hwan,Kim, Kang Lib,Jeong, Beomjin,Huh, June,Park, Cheolmin The Royal Society of Chemistry 2016 Nanoscale Vol.8 No.19

<P>The characteristic source-drain current hysteresis frequently observed in field-effect transistors with networked single walled carbon-nanotube (NSWNT) channels is problematic for the reliable switching and sensing performance of devices. But the two distinct current states of the hysteresis curve at a zero gate voltage can be useful for memory applications. In this work, we demonstrate a novel non-volatile transistor memory with solution-processed NSWNTs which are suitable for multilevel data programming and reading. A polymer passivation layer with a small amount of water employed on the top of the NSWNT channel serves as an efficient gate voltage dependent charge trapping and de-trapping site. A systematic investigation evidences that the water mixed in a polymer passivation solution is critical for reliable nonvolatile memory operation. The optimized device is air-stable and temperature-resistive up to 80 degrees C and exhibits excellent non-volatile memory performance with an on/off current ratio greater than 10(4), a switching time less than 100 ms, data retention longer than 4000 s, and write/read endurance over 100 cycles. Furthermore, the gate voltage dependent charge injection mediated by water in the passivation layer allowed for multilevel operation of our memory in which 4 distinct current states were programmed repetitively and preserved over a long time period.</P>

Development of a bendable pyramidal kagome structure and its structural characteristics

Hwang, June-Sun,Choi, Tae-Gyun,Lee, Dongyoung,Lyu, Min-Young,Lee, Dai Gil,Yang, Dong-Yol Elsevier 2016 COMPOSITE STRUCTURES -BARKING THEN OXFORD- Vol.142 No.-

<P><B>Abstract</B></P> <P>A sandwich construction is an effective lightweight structure. Conventionally, sandwich structures have been fabricated as plane panels with limitation of application to curved components. In this work, a bendable structure that can be applied to the curved surface was developed based on the pyramidal kagome (PK) structure. The bending zone adaptable to the curved surface was designed between the neighboring PK structures. The PK sandwich structure was strengthened by developing the cross-sectional design of the strut. The mechanical characteristics were investigated by three-point bending test and compression test. The semi-circular cross-section (SCC)-based PK sandwich structure showed improved bending stiffness and maximum bending load over those of the conventional flat rectangular cross-section (FRC)-based PK sandwich structure. The curved PK sandwich structure was applied to the curved component.</P>

Membrane Perturbation Induced by Papiliocin Peptide, Derived from Papilio xuthus, in Candida albicans

( June Young Lee ),( Jae Sam Hwang ),( Bo Mi Hwang ),( Jin Kyoung Kim ),( Seong Ryul Kim ),( Yang Mee Kim ),( Dong Gun Lee ) 한국미생물 · 생명공학회 2010 Journal of microbiology and biotechnology Vol.20 No.8

Previously, papiliocin was isolated from the swallowtail butterfly Papilio xuthus and its antimicrobial activity was suggested. In this study, the antifungal mechanism of papiliocin against Candida albicans was investigated. Confocal laser scanning microscopy (CLSM) and 1, 6-diphenyl-1, 3, 5-hexatriene (DPH) fluorescence analysis indicated that papiliocin disturbed the fungal plasma membrane. Moreover, the assessment of the release of FITC-dextran (FD) from liposomes further demonstrated that the antifungal mechanism of papiliocin could have originated from the pore-forming action and that the radius of the pores was presumed to be anywhere from 2.3 to 3.3 nm.

A Fuzzy Logic Controller for Speed Control of a DC Series Motor Using an Adaptive Evolutionary Computation

Hwang, Gi-Hyun,Hwang, Hyun-Joon,Kim, Dong-Wan,Park, June-Ho Institute of Control 2000 Transaction on control, automation and systems eng Vol.2 No.1

In this paper, an Adaptive Evolutionary Computation(AEC) is proposed. AEC uses a genetic algorithm(GA) and an evolution strategy (ES) in an adaptive manner is order to take merits of two different evolutionary computations: global search capability of GA and local search capability of ES. In the reproduction procedure, proportions of the population by GA and ES are adaptively modulated according to the fitness. AEC is used to design the membership functions and the scaling factors of fuzzy logic controller (FLC). To evaluate the performances of the proposed FLC, we make an experiment on FLC for the speed control of an actual DC series motor system with nonlinear characteristics. Experimental results show that the proposed controller has better performance than that of PD controller.

Pastoral Ethical Leadership in Church Administration and the Decision-Making Process

Hwang, Byung-June 한국실천신학회 2010 신학과 실천 Vol.0 No.25

The purpose of the study is to articulate pastoral ethical leadership in church administration and the decision-making process. In the 21st century, as society becomes even more demographically diverse, pastors need to be able to develop, foster, and lead tolerant and democratic faith community. Church leaders, today, will have more difficulties of decision-makings and face real-life dilemmas in their churches and communities. From this point of view, ethical leadership is necessary for church administrators and leaders to solve the dilemmas in their everyday decision making process. Moreover, pastoral leaders need moral principles which inform and guide lay leaders who make hard choice under complex and ambiguous circumstances. Through the study of ethics, thus, pastoral leaders of tomorrow will be better prepared to recognize, reflect on, and appreciate differences. This need for ethical preparation is important for church leaders in an increasingly diverse society. This study will attempt to synthesize and explain a large body of literature with which pastoral leaders want and need to be familiar. First, it will explore the nature of leadership and pastoral leadership. Then, it will explain the needs of ethical leadership in church administration and decision making. Next, it will introduce a multiple ethical paradigm approach to assist church leaders in grappling with complexity and diversity. Finally, it will discuss William Grace’s the four "V" model for ethical leadership development in administration programs.