• 정신신체의학
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• 제4권2호
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• pp.269-276
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• 1996

신체형장애의 정신역동에 대하여 이론적 고찰을 하였다. 신체화(身體化)란 본능적 욕동을 방어하는 과정에서 생긴 갈등을 정신적으로 처리하지 못하고. 신체 증상으로 처리하는 것을 말한다(Moore 1990). Ford(1983)는 인생을 사는 방법 중의 하나라고 하였고, Dunbar(1954)는 정신 에너지가 신체증상으로 바뀌어진 것이라고 했다. Schur(1955)에 의하면, 신체화(身體化)는 갈등에 의해서 일어나는 하나의 퇴행현상이라고 한다. Schur는 이런 현상을 '재(再) 신체화(身體化)(resomatization)'라 했다. 갈등의 신체화(身體化) 반응중 가장 흔한 것이 통증(痛症)(pain)이다. 통증(痛症)은 어린시절의 경험에서 유래한 무의식적 의미를 가지고 있다. 통증(痛症)(pain)은 사랑 획득의 방법이며, 잘못한 행동에 대한 벌로 사용되기도 하고, 속죄(贖罪)의 수단이 되기도 한다. 통증(痛症)중에서도 흉통(胸痛)(chest pain)은 특별한 의미를 갖는다. 일반적으로 '가슴이 아프다'는 말은 '마음이 아프다'는 의미와 같이 쓰인다. 그리고 가슴은 마음을 상징하고 마음은 심장을 생각나게 하여 마음의 아픔을 심장의 통증(痛症)(pain)으로 인식하는 경향이 높다. Kellner(1990)는 적개심과 분노, 특히 억압된 적개심이 신체화(身體化)의 중요한 인자라고 하였다. 정신분석가인 Bacon(1953)dms '심장동통(心臟疼痛)에 대한 정신분석적 관찰'에서 정신분석 시간에 사랑받고 싶은 욕구가 좌절된 환자가 이로 인한 분노와 두려움 때문에 왼편 가슴에서 왼쪽 팔로 뻗쳐 내려가는 심장동통을 호소하는 증례(症例)들을 발표했다. 그녀는 심장동통과 관계된 욕구들이 의존욕구와 공격욕구라고 하였다. 신체형장애의 정신치료에서는 공감적인 관계와 치료적 동맹이 필수적이며, 증상시작의 시점을 중심으로 유발인자를 가려내고 증상과 유발인자의 관계를 이해하도록 돕는 것이 출발이다. 증상을 통하여 표현되고 있는 환자의 심리내적인 갈등을 발견하여 해석해 주는 것이 치료의 과정이다. 이런 기법을 기초로 치료한 세 사람의 신체형장애 증례를 소개하였다. 첫 번째 소개한 히스테리성 실어증을 가진 H군은 억압된 분노가 역동적인 원인이었다. 유발인자와 관련지어 해석을 해주었고, 이차이득을 얻은 후에 회복되었다. 두 번째 소개한 심장노이로제에 빠진 치과의사의 경우는 아버지의 사랑을 잃을 것에 대한 불안이 역동적 원인이었다. 유발인자와 관련지어 증상을 해석하였고, 아버지의 사랑을 잃을까봐 두려워하는 마음속의 아이를 보여주었고, 이제는 어른이 되었으니 자신의 주인이 되어 살라고 교육적인 해석을 듣고 호전되었다. 세 번째 부인은 심한 흉통발작으로 내과에서 의뢰되어 왔는데 의존욕구의 좌절과 이로 인한 분노, 그리고 분리 불안이 역동적 원인이었다. 이 부인은 holter monitor를 메자 증상이 극적으로 사라졌는데 이것을 계기로 자신의 중상이 심인성이라는 것을 알고부터 치료동맹이 이루어졌고, 그 후 정기적인 정신치료 시간에는 증상과 유발인자들 사이의 관계를 해석해 주었다. 이를 통하여 분리불안이 증상과 관계되어 있다는 것을 이해하고 환자는 증상이 일어나도 덜 두려워하게 되었고, 해외여행이나 사회적인 활동이 가능해졌다.

• 한국조리학회지
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• 제16권2호
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• pp.351-366
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• 2010

초등학교 아동들의 식습관 개선을 위한 영양 교육용 자료로 어린이용 요리책을 개발하고자 본 연구를 수행하였다. 강원도 일부 초등학교 5, 6학년 학생 90명(남자 45명, 여자 45명)을 대상으로 식행동을 분석한 결과, 아침 식사를 매일 먹는 아동은 48.9%, 아침을 결식하는 이유는 48.9%가 '시간이 없어서'라고 응답하였다. 아침 식사 시 주로 먹는 음식은 한식(67.8%)이었으며, 집에 혼자 있을 때 식사를 해결하는 방법은 42.2%가 '먹고 싶은 것을 만들어 먹는다'고 응답하였다. 간식 섭취 실태를 보면 '하루에 1~2회' 간식을 먹는 아동이 52.2%로 가장 많았고, 주로 먹는 간식의 종류는 과일류(46.6%), 아이스크림류(22.2%), 빵이나 과자(21.1%), 패스트푸드(11.1%)로 조사되었다. 아동들은 전반적으로 채소류를 싫어하고, 육류를 좋아하며, 좋아하는 식품은 비교적 다양한 편인데 반해 싫어하는 식품은 몇 몇 식품에 편중되고 기호가 더 뚜렷하였다. 선호하는 조리법으로는 볶음(27.8%), 튀김(25.6%), 국이나 찌개(21.1%)가 선택되었다. 아동의 96.7%가 최소한 1회 이상의 요리 경험이 있었으며, 요리를 해 본 이유로는 그냥 '요리를 해 보고 싶어서'가 64.4%로 가장 많았다. 지금까지 요리해 본 음식으로는 라면(68.8%), 계란 후라이(53.3%), 볶음밥(37.8%), 샌드위치(18.9%)의 순서로 조사되었다. 이러한 식행동 분석 결과를 토대로 아동을 위한 요리책은 크게 '혼자서 잘해요', '초간단 간식 만들기', '내 솜씨를 뽐내요'의 세 부분으로 나누어 각각 5~6개의 메뉴로 구성하여 개발되었다. 요리책은 조리 과정 사진과 열량 및 영양소 함량, 균형 잡힌 한 끼 식사를 구성하는 방법, 적절한 1인 분량에 대한 정보를 제공하였다. 또한 위생과 안전, 계량 방법, 음식물 쓰레기 분리 및 뒷정리 등 요리 활동에 필요한 기본적인 지식을 습득할 수 있도록 하였다. 개발된 요리책은 아동 스스로 요리 활동에 참여하게 함으로써 결식이나 편식 등의 잘못된 식행동을 개선하고, 올바른 식생활을 영위하는데 필요한 기본적인 영양지식을 제공하는 등 영양 교육 자료로써의 효과가 있을 것으로 기대된다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권4호
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• pp.299-305
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• 2010

Purpose: Adipose tissue is located beneath the skin, around internal organs, and in the bone marrow in humans. Its main role is to store energy in the form of fat, although it also cushions and insulates the body. Adipose tissue also has the ability to dynamically expand and shrink throughout the life of an adult. Recently, it has been shown that adipose tissue contains a population of adult multipotent mesenchymal stem cells and endothelial progenitor cells that, in cell culture conditions, have extensive proliferative capacity and are able to differentiate into several lineages, including, osteogenic, chondrogenic, endothelial cells, and myogenic lineages. Materials and Methods: This study focused on endothelial cell culture from the adipose tissue. Adipose tissues were harvested from buccal fat pad during bilateral sagittal split ramus osteotomy for surgical correction of mandibular prognathism. The tissues were treated with 0.075% type I collagenase. The samples were neutralized with DMEM/and centrifuged for 10 min at 2,400 rpm. The pellet was treated with 3 volume of RBC lysis buffer and filtered through a 100 ${\mu}m$ nylon cell strainer. The filtered cells were centrifuged for 10 min at 2,400 rpm. The cells were further cultured in the endothelial cell culture medium (EGM-2, Cambrex, Walkersville, Md., USA) supplemented with 10% fetal bovine serum, human EGF, human VEGF, human insulin-like growth factor-1, human FGF-$\beta$, heparin, ascorbic acid and hydrocortisone at a density of $1{\times}10^5$ cells/well in a 24-well plate. Low positivity of endothelial cell markers, such as CD31 and CD146, was observed during early passage of cells. Results: Increase of CD146 positivity was observed in passage 5 to 7 adipose tissue-derived cells. However, CD44, representative mesenchymal stem cell marker, was also strongly expressed. CD146 sorted adipose tissue-derived cells was cultured using immuno-magnetic beads. Magnetic labeling with 100 ${\mu}l$ microbeads per 108 cells was performed for 30 minutes at $4^{\circ}C$ a using CD146 direct cell isolation kit. Magnetic separation was carried out and a separator under a biological hood. Aliquous of CD146+ sorted cells were evaluated for purity by flow cytometry. Sorted cells were 96.04% positivity for CD146. And then tube formation was examined. These CD146 sorted adipose tissue-derived cells formed tube-like structures on Matrigel. Conclusion: These results suggest that adipose tissue-derived cells are endothelial cells. With the fabrication of the vascularized scaffold construct, novel approaches could be developed to enhance the engineered scaffold by the addition of adipose tissue-derived endothelial cells and periosteal-derived osteoblastic cells to promote bone growth.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.31-31
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• 2010

The growth of the high-quality GaN epilayers is of significant technological importance because of their commercializedoptoelectronic applications as high-brightness light-emitting diodes (LEDs) and laser diodes (LDs) in the visible and ultraviolet spectral range. The GaN-based heterostructural epilayers have the polar c-axis of the hexagonal structure perpendicular to the interfaces of the active layers. The Ga and N atoms in the c-GaN are alternatively stacked along the polar [0001] crystallographic direction, which leads to spontaneous polarization. In addition, in the InGaN/GaN MQWs, the stress applied along the same axis contributes topiezoelectric polarization, and thus the total polarization is determined as the sum of spontaneous and piezoelectric polarizations. The total polarization in the c-GaN heterolayers, which can generate internal fields and spatial separation of the electron and hole wave functions and consequently a decrease of efficiency and peak shift. One of the possible solutions to eliminate these undesirable effects is to grow GaN-based epilayers in nonpolar orientations. The polarization effects in the GaN are eliminated by growing the films along the nonpolar [$11\bar{2}0$] ($\alpha$-GaN) or [$1\bar{1}00$] (m-GaN) orientation. Although the use of the nonpolar epilayers in wurtzite structure clearly removes the polarization matters, however, it induces another problem related to the formation of a high density of planar defects. The large lattice mismatch between sapphiresubstrates and GaN layers leads to a high density of defects (dislocations and stacking faults). The dominant defects observed in the GaN epilayers with wurtzite structure are one-dimensional (1D) dislocations and two-dimensional (2D) stacking faults. In particular, the 1D threading dislocations in the c-GaN are generated from the film/substrate interface due to their large lattice and thermal coefficient mismatch. However, because the c-GaN epilayers were grown along the normal direction to the basal slip planes, the generation of basal stacking faults (BSFs) is localized on the c-plane and the generated BSFs did not propagate into the surface during the growth. Thus, the primary defects in the c-GaN epilayers are 1D threading dislocations. Occasionally, the particular planar defects such as prismatic stacking faults (PSFs) and inversion domain boundaries are observed. However, since the basal slip planes in the $\alpha$-GaN are parallel to the growth direction unlike c-GaN, the BSFs with lower formation energy can be easily formed along the growth direction, where the BSFs propagate straightly into the surface. Consequently, the lattice mismatch between film and substrate in $\alpha$-GaN epilayers is mainly relaxed through the formation of BSFs. These 2D planar defects are placed along only one direction in the cross-sectional view. Thus, the nonpolar $\alpha$-GaN films have different atomic arrangements along the two orthogonal directions ($[0001]_{GaN}$ and $[\bar{1}100]_{GaN}$ axes) on the $\alpha$-plane, which are expected to induce anisotropic biaxial strain. In this study, the anisotropic strain relaxation behaviors in the nonpolar $\alpha$-GaN epilayers grown on ($1\bar{1}02$) r-plane sapphire substrates by metalorganic chemical vapor deposition (MOCVO) were investigated, and the formation mechanism of the abnormal zigzag shape PSFs was discussed using high-resolution transmission electron microscope (HRTEM).

• 공업화학
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• 제29권1호
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• pp.81-96
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• 2018

본 연구에서는 천연 소재인 경옥가루의 물리화학적 특성을 조사하고 이를 함유한 워시오프 팩과 리퀴드 파운데이션을 제조하였다. 또한 이들 제형을 대상으로 각 제형이 주는 효과와 사용자 관능 평가, 제형 안정성 및 피부 안전성 평가를 수행하였다. 워시오프 팩 중의 경옥가루의 함량이 증가할수록 원적외선 방사율과 방사에너지 값이 증가하였고, 경옥가루를 3% 함유한 제품에서는 피부 적용 시 피부 온도가 약 $0.5^{\circ}C$ 상승하였다. 경옥가루를 첨가한 리퀴드 파운데이션은 피부 본래의 색을 더욱 선명하게 표현할 수 있는 채도를 나타냈다. 경옥가루를 첨가한 워시오프 팩과 리퀴드 파운데이션은 각각의 수분 보유량이 최대 5.0% 및 63.0%로 나타났다. 사용자 관능 평가에서 경옥가루를 함유한 워시오프 팩 제형은 피부친화력, 밀착력, 가려움 및 촉촉함을 개선시켰다. 경옥가루를 함유한 리퀴드 파운데이션도 대조군 제형과 비교했을 때 커버력을 제외한 모든 항목에서 개선이 이루어졌다. 경옥가루 함유 제형에 대해 8주간 안정성 평가를 한 결과 육안상으로 변색이나 분리현상은 관찰되지 않았으며 pH는 8주까지, 점도는 4주까지 안정함을 확인하였다. 또한, 피부 안전성 평가에서 경옥가루 함유 제형은 모두 자극이 없는 것으로 나타났다. 결론적으로, 경옥가루는 무기안료로써 안정성과 안전성이 확보된 새로운 다기능 소재로써 화장품에 응용 가능성이 있음을 시사하였다.

• 자원환경지질
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• 제43권2호
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• pp.137-148
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• 2010

백악기 불국사화강암 내 열극을 충진한 함금은석영맥으로 구성된 명보광산은 전남 보성군에 위치한 광산이다. 본 연구에서는 명봉광산의 광미를 채취하여 광미 내 황화광물 풍화와 이차 삼차 광물 생성 또는 변질 등의 다양한 과정들이 비소의 고정화에 어떠한 영향을 미치는지 살펴보았다. 광물학적 화학적 방법으로 나누어 연구를 수행하였으며, 광물학적 방법으로는 비중/자력 선별, 초음파 서}척, 기기분석(X-선 회절 분석기, 에너지 분산분광기, 전자탐침미세현미경) 등이 이용되었다. 그리고 왕수분해법을 적용하여 광미 내 원소함량을 알아보았다. 연구결과, 광미의 풍화로 형성된 철 (산)수산화물은 충진, 침전, 변질 등의 3가지 형태로 존재하는 것으로 확인되었다. 즉, 황철석의 가장자리와 균열부를 충진하는 형태, 맥석광물을 피복하여 침전된 형태 그리고 유코나이트로 변질된 형태 등이었다. 초기 다량의 산-발생 광물인 황철석과 유비철석의 풍화로 인해 산화반응이 빠르게 일어나면서 많은 철 (산)수산화물과 스코로다이트 등이 이차적으로 생성되는 것이 인지되었다. 이와 더불어 산화 환경에 대한 노출기간이 길어지고 산-발생 광물이 소모되면서 광미 내 pH 감소속도는 점차적으로 줄어들게 될 뿐만 아니라 주변 모암 내 함유된 방해석과의 중화반응이 더 크게 기여함으로써 광미의 pH는 증가한 것으로 생각된다. 이러한 광미 내 pH의 상승으로 인하여 이차적으로 생성된 스코로다이트의 안정도가 감소하면서 비소가 재용출 되어진다. 또한 방해석과 스코로다이트로부터 용출된 칼슘이온과 비소이온이 국부적으로 농집되면서 삼차적으로 유코나이트로 성장하게 되고, 이러한 비산염광물의 일종인 유코나이트는 비소의 함량이 높은 광물로서 비소를 고정화시키는데 크게 기여한 것으로 판단된다. 뿐만 아니라 광미의 주요한 일차광물인 황철석이 풍화되면서 생성된 다량의 철 (산)수산화물은 비소의 거동에 대하여 제어능력이 큰 것으로 인지되었다. 결론적으로 본 연구는 이러한 일련의 과정에 통하여 일차적으로 용출되거나 이차적으로 재용출된 비소는 흡착, 공침, 흡수 등과 같은 다양한 수착 반응들로 인해 고정화됨을 확인하였다.

• 한국식품영양학회지
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• 제11권2호
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• pp.179-184
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• 1998

양파를 생채로 착즙하여 분리한 액즙을 Brix 70%까지 감압농축시킨 것과 이어서 잔사에 ethyl alcohol을 가하여 추출한 것을 농축시켜 같이 합하고, 갈변방지를 위하여 1% cysteine의 첨가와 유화제로서 2% PGDR을 첨가하여 양파 oleoresin을 저장중 품질 안정성을 검토하였다. 양파로부터 oleoresin에 추출된 당은 저장온도 5$^{\circ}C$, $25^{\circ}C$ 및 4$0^{\circ}C$에서 매우 안정하여 저장 60일후까지도 함량변화는 거의 일어나지 않았다. 양파 oleoresin 추출 직후 갈변도를 나타내는 흡광도가 0.38로 담갈색을 띄었는데 5$^{\circ}C$에서는 저장 60일 후에도 변화가 거의 없었으나, $25^{\circ}C$ 및 4$0^{\circ}C$에서 저장한 경우는 60일후 흡광도가 1.53 및 3.32로 증가하였고, cysteine을 1% 첨가한 경우는 대조구에 비하여 갈색 억제효과가 상당히 나타나 4$0^{\circ}C$에서 60일간 저장하였을 때의 흡광도는 대조구의 절반 수준으로 나타났다. 유화 안정성은 5$^{\circ}C$ 저장의 경우 20일, 40일 및 60일 후에 분리되지 않는 emulsion 층의 부피가 각각 96.8%, 94.1% 및 9.06%로 매우 안정하였고, $25^{\circ}C$ 및 4$0^{\circ}C$에서 60일간 저장 후는 83.2% 및 75.4%로 유화상태가 다소 불안정하였다. 생체 양파로부터 추출한 oleoresin을 저장시키지 않고 바로 대두유에 1%를 첨가한 경우와 0.02% BHA를 첨가하였을 때 A.I.는 각각 1.39 및 1.72를 나타내어 0.02% BHA를 첨가한 대두유의 유도기간 연장효과에 대하여 80.8%에 해당하는 항산화 활성을 나타내었고, 5$^{\circ}C$ 및 $25^{\circ}C$에서 60일 동안 저장한 양파 oleoresin을 대두유에 각각 1% 첨가하였을 때의 A.I.는 1.37 및 1.30을 나타내어 실온 또는 그 이하의 온도에서는 양파 oleoresin이 가지는 항산화 활성은 매우 안정하였으며, 4$0^{\circ}C$에서 저장 60일후의 양파 oleoresin의 A.I.는 1.08로 나타나 고온에서 저장기일이 길수록 불안정하였다. Overall odor intensity의 지표로서 total pyruvate 함량변화는 5$^{\circ}C$, $25^{\circ}C$ 및 4$0^{\circ}C$에서 저장 60일 후 잔존율이 각각 89.9%, 79.7% 및 65.2%로 저온에서 상당히 안정하였다. 양파 oleoresin의 저장중 pyruvate 감소에 대한 반응속도 상수는 저장온도 범위 5~4$0^{\circ}C$에서 1.381~4.735m㏖/$\ell$.hr, Q10 값은 1.537~1.694, 그리고 활성화 에너지는 11.649㎉/g mole이었다.

• 생물환경조절학회지
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• 제24권2호
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• pp.100-105
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• 2015

온실의 난방부하 중 틈새환기전열부하 산정방법은 설계 기준마다 제각각이고, 온실의 규모에 따라 각각의 방법에는 큰 차이가 있으므로 보다 정확히 국내에 적용할 수 있는 방법을 정립할 필요가 있다. 본 연구에서는 원예시설의 환경설계 중 난방부하 산정방법 정립에 필요한 기초자료를 제공할 목적으로 다양한 종류의 보온커튼을 설치한 단동 및 연동 플라스틱 온실에서 추적가스법을 이용하여 틈새환기율을 실측하였으며, 온실의 틈새환기 전열부하 산정방법을 검토하였다. 연동온실의 틈새환기율은 $0.042{\sim}0.245h^{-1}$의 범위로 측정되었으며 단동온실의 틈새환기율은 $0.056{\sim}0.336h^{-1}$의 범위로 측정되어 단동온실이 약간 큰 것으로 나타났다. 온실의 틈새환기율은 단동, 연동 구분없이 보온커튼의 층수에 따라 크게 감소하는 것으로 나타났다. 또한 틈새환기율은 온실의 실내외 기온차가 커질수록 증가하는 경향을 보였으나, 실험기간 동안의 낮은 풍속 범위에서 외부 풍속에 따른 틈새환기율의 변화는 일정한 경향을 찾을 수 없었다. 온실의 난방설계를 위한 틈새환기율은 적정 실내외 기온차에서의 값을 제시할 필요가 있고, 최대난방부하 산정의 기준이 되는 낮은 풍속 범위에서 풍속에 따른 틈새환기율의 변화는 고려하지 않아도 되는 것으로 고찰되었다. 다만 강풍지역에서는 열관류율을 포함하여 최대난방부하를 약간 증가시키는 보정계수의 적용이 필요할 것으로 판단되었다. 온실의 틈새환기전열부하 산정방법을 검토한 결과 틈새환기전열계수와 온실의 피복면적을 이용하는 방법은 문제가 있는 것으로 나타났으며, 틈새환기율과 온실의 체적을 이용하는 방법이 합리적인 것으로 판단되었다.

• 한국막학회:학술대회논문집
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• 한국막학회 1999년도 The 7th Summer Workshop of the Membrane Society of Korea
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• pp.39-42
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• 1999

Perfluoropolymers represent the ultimate resistance to hostile chemical environments and high service temperature, attributed to the presence of fluorine in the polymer backbone, i.e. to the high bond energy of C-F and C-C bonds of fluorocarbons. Copolymers of Tetrafluoroethylene (TEE) and 2, 2, 4Trifluoro-5Trifluorometoxy- 1, 3Dioxole (TTD), commercially known as HYFLON AD, are amorphous perfluoropolymers with glass transition temperature (Tg)higher than room temperature, showing a thermal decomposition temperature exceeding 40$0^{\circ}C$. These polymer systems are highly soluble in fluorinated solvents, with low solution viscosities. This property allows the preparation of self-supported and composite membranes with desired membrane thickness. Symmetric and asymmetric perfluoropolymer membranes, made with HYFLON AD, have been prepared and evaluated. Porous and not porous symmetric membranes have been obtained by solvent evaporation with various processing conditions. Asymmetric membranes have been prepared by th wet phase inversion method. Measure of contact angle to distilled water have been carried out. Figure 1 compares experimental results with those of other commercial membranes. Contact angles of about 120$^{\circ}$for our amorphous perfluoropolymer membranes demonstrate that they posses a high hydrophobic character. Measure of contact angles to hexandecane have been also carried out to evaluate the organophobic character. Rsults are reported in Figure 2. The observed strong organophobicity leads to excellent fouling resistance and inertness. Porous membranes with pore size between 30 and 80 nanometers have shown no permeation to water at pressures as high as 10 bars. However high permeation to gases, such as O2, N2 and CO2, and no selectivities were observed. Considering the porous structure of the membrane, this behavior was expected. In consideration of the above properties, possible useful uses in th field of gas- liquid separations are envisaged for these membranes. A particularly promising application is in the field of membrane contactors, equipments in which membranes are used to improve mass transfer coefficients in respect to traditional extraction and absorption processes. Gas permeation properties have been evaluated for asymmetric membranes and composite symmetric ones. Experimental permselectivity values, obtained at different pressure differences, to various single gases are reported in Tab. 1, 2 and 3. Experimental data have been compared with literature data obtained with membranes made with different amorphous perfluoropolymer systems, such as copolymers of Perfluoro2, 2dimethyl dioxole (PDD) and Tetrafluorethylene, commercialized by the Du Pont Company with the trade name of Teflon AF. An interesting linear relationship between permeability and the glass transition temperature of the polymer constituting the membrane has been observed. Results are descussed in terms of polymer chain structure, which affects the presence of voids at molecular scale and their size distribution. Molecular Dyanmics studies are in progress in order to support the understanding of these results. A modified Theodoru- Suter method provided by the Amorphous Cell module of InsightII/Discover was used to determine the chain packing. A completely amorphous polymer box of about 3.5 nm was considered. Last but not least the use of amorphous perfluoropolymer membranes appears to be ideal when separation processes have to be performed in hostile environments, i.e. high temperatures and aggressive non-aqueous media, such as chemicals and solvents. In these cases Hyflon AD membranes can exploit the outstanding resistance of perfluoropolymers.

• 대한의용생체공학회:의공학회지
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• 제6권2호
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• pp.1-8
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• 1985

The wall shear stress in the vicinity of end-to end anastomoses under steady flow conditions was measured using a flush-mounted hot-film anemometer(FMHFA) probe. The experimental measurements were in good agreement with numerical results except in flow with low Reynolds numbers. The wall shear stress increased proximal to the anastomosis in flow from the Penrose tubing (simulating an artery) to the PTFE: graft. In flow from the PTFE graft to the Penrose tubing, low wall shear stress was observed distal to the anastomosis. Abnormal distributions of wall shear stress in the vicinity of the anastomosis, resulting from the compliance mismatch between the graft and the host artery, might be an important factor of ANFH formation and the graft failure. The present study suggests a correlation between regions of the low wall shear stress and the development of anastomotic neointimal fibrous hyperplasia(ANPH) in end-to-end anastomoses. 30523 T00401030523 ^x Air pressure decay(APD) rate and ultrafiltration rate(UFR) tests were performed on new and saline rinsed dialyzers as well as those roused in patients several times. C-DAK 4000 (Cordis Dow) and CF IS-11 (Baxter Travenol) reused dialyzers obtained from the dialysis clinic were used in the present study. The new dialyzers exhibited a relatively flat APD, whereas saline rinsed and reused dialyzers showed considerable amount of decay. C-DAH dialyzers had a larger APD(11.70$\pm$1.32mmHg/min)compared to CF dialyzers(4.32$\pm$0.55mmHg/min)(p<0.05). However, there was no observable difference in the UFR between the two dialyzers. Neither APD nor UFR showed any significant increase with an increasing number of reuses for up to more than 20reuses. A substantial number of failures observed in APD(larger than 20mmHe/min)on the reused dialyzers(2 out of 40 CP and S out 26 C-DAK) were attributed to the Possible damage on the fibers. The CF 15-11 HFDs which failed APD test did not show changes in the UFR compared to normal dialyzers indicating that APD is a more sensitive test than UFR test to evaluate the integrity of the fibers. 30527 T00401030527 ^x For quantitative measurement of reflected light from a clinical diagnostic strip, a prototype old reflectance photometer was designed. The strip loader and cassette were made to obtain more accurate reflectance parameters. The strip was illuminated at 45˚c through optical fiber and the intensity of reflected light was determined at rectanguLat angle using a photodiode. The kubelka-munk coefficient and reflection optical density were determined ar four different wavelengths(500, 550, 570 and 610nm) for blood glucose strip. For higher concentration than 300mg/41 about glucose, a saturation state of abforbance was observed at 500, 550 and 570nm. The correlation between glucose concentration and parameters was the best at 610nm. 30535 T00401030535 ^x Radiation-induced fibrosarcoma tumors were grown on the flanks of C3H mice. The mice were divided into two groups. One group was injected with Photofrin II, intravenously (2.5mg/kg body weight). The other group received no Photofrin II. Mice from both groups were irradialed for approximately 15 minutes at 100, 300, or 500 mW/cm2 with the argon (488nm/514.5 nm), dye(628nm) and gold vapor (pulsed 628 nm) laser light. A photosensitizer behaved as an added absorber. Under our experimental conditions, the presence of Photolfrin II increased surface temperature by at least 40% and the temperature rise due to 300 mW/cm2 irradiation exceeded values for hyperthermia. Light and temperature distributions with depth were estimated by a computer model. The model demonstrated the influence of wavelength on the thermal process and proved to be a valuable tool to investigate internal temperature rise. 30536 T00401030536 ^x We investigated the structural geometry of thirty-eight Korean femurs. The purpose of this study is to identify major geometrical differences between Korean femurs 3nd others that we believe belong to Caucasians so that we would be able to get insights into the femoral component design that fits Asians including Koreans. We utilized computerized tomography (CT) images of femurs extracted from cadavers. The CT images were transformed into bitmap data by using a film scanner, and then analyzed by using a commercially available software called Image v.1.0 and a Macintosh IIci computer.The resulting data were compared with already published data. The major results show that the geometry of the Korean femurs is significantly different from that of Caucasians: (1) the anteversion angle and the canal flare index are greater by the amount of approximately 8˚ and 0.5, respectively, (2) the shape of the isthmus cross section is more round, and (3) the distance between the teaser trochanter and the proximal border of the isthmus is shelter by about 15 mm. The results suggested that the femoral component suitable for Asians should be different from the currently-used components designed and manufactured mostly by European or American companies. 30537 T00401030537 ^x It is well known that nonlinear propagation characteristics of the wave in the tissue may give very useful information for the medical diagnoisis. In this paper, a new method to detect nonlinear propagation characteristics of the internal vibration in the tissue for the low frequency mechanical vibration by using bispectral analysis is proposed. In the method, low frequency vibration of f0( = 100Hz) is applied on the surface of the object, and the waveform of the internal vibration x (t) is measured from Doppler frequency modulation of silmultaneously transmitted probing ultrasonic waves. Then, the bispectra of the signal x (t) at the frequencies (f0, f0) and (f0, 2f0) are calculated to estimate the nonlinear propagation characteristics as their magnitude ratio, w here since bispectrum is free from the gaussian additive noise we can get the value with high S/N. Basic experimental system is constructed by using 3.0 MHz probing ultrasonic waves and the several experiments are carried out for some phantoms. Results show the superiority of the proposed method to the conventional method using power spectrum and also its usefulness for the tissue characterization. 30541 T00401030541 ^x This paper describes the implementation of a computerized radial pulse diagnosis by aids of a clinical expert. On this base, we composed of the radial pulse diagnosis system in korean traditional medicine. The system composed of a radial pulse wave detection system and a radial pulse diagnosis system. With a detection system, we detected Inyoung and Cheongu radial pulse wave and processed it. Then, we have got the characteristic parameters of radial pulse wave and also quantified that according to the method of Inyoung-Cheongu Comparison Radial Pulse Diagnosis. We defined the jugement standard of radial pulse diagnosis system and then we confirmed the possibility for realization of automatic radial pulse diagnosis in korean traditional medicine. 30545 T00401030545 ^x Microspheres are expected to be applied to biomedical areas such as solid-phase immunoassays, drug delivery systems, immunomagnetic cell separation. To synthesize microspheres for biomedical application, "two stage shot growth method" was developed. The uniformity ratio of synthesized microspheres was always smaller than 1.05. And the surface charge density (or the number of ionizable functional groups) of the microspheres synthesized by "two stage shot growth method" was 6~13 times higher than that of the microspheres synthesized by conventional seeded batch copolymerization. As a previous step for biomedical application, adsorption experiments of bovine albumin on microspheres were carried out under various conditions. The maximum adsorbed amount was obtained in the neighborhood of pH 4.5. Isoelectric point of bovine albumin is pH 5.0, so experimental result shows that it shifted to acid area. The adsorption isotherm was obtained, the plateau region was always reached at 2.Og/L (bulk concentration of bovine albumin).The effect of the kind and the amount of surface functional group was also examined. 30575 T00401030575 ^x A medical image workstation was developed using multimedia technique. The system based on PC-486DX was designed to acquire medical images produced by medical imaging instruments and related audio information, that is, doctors' reporting results. Input information was processed and analyzed, then the results were presented in the form of graph and animation. All the informations of the system were hierarchically related with the image as the apex. Processing and analysis algorithms were implemented so that the diagnostic accuracy could be improved. The diagnosed information can be transferred for patient diagnosis through LAN(local area network). 30592 T00401030592 ^x In the conventional infrared imaging system, complex infrared lens systems are usually used for directing collimated narrow infrared beams into the high speed 2-dimensional optic scanner. In this paper, a simple reflective infrared optic system with a 2-dimensional optic scanner is proposed for the realization of medical infrared thermography system. It has been experimentally proven that the intfrared thermography system composed of the proposed optic system has the temperature resolution of 0.1˚c under the spatial resolution of lmrad, the image matrix size of 256 X 240, and tile imaging time of 4 seconds. 30593 T00401030593 ^x In this paper, MIIS (Medical Image Information System) has been designed and implemented using INGRES RDBMS, which is based on a client/server architecture. The implemented system allows users to register and retrieve patient information, medical images and diagnostic reports. It also provides the function to display these information on workstation windows simultaneously by using the designed menu-driven graphic user interface. The medical image compression/decompression techniques are implemented and integrated into the medical image database system for the efficient data storage and the fast access through the network. 30594 T00401030594 ^x In this paper, computerized BEAM was implemented for the space domain analysis of EEG. Trans-formation from temporal summation to two-dimensional mappings is formed by 4 nearest point inter-polaton method. Methods of representation of BEAM are two. One is dot density method which classify brain electrical potential 9 levels by dot density of gray levels and the other is colour method which classify brain electrical 12 levels by red-green colours. In this BEAM, instantaneous change and average energy distribution over any arbitrary time interval of brain electrical activity could be observed and analyzed easily. In the frequency domain, the distribution of energy spectrum of a special band can easily be distinguished normality and abnormality. 30608 T00401030608 ^x Laboratory information system (LIS) is a key tool to manage laboratory data in clinical pathology. Our department has developed an information system for routine hematology using down-sized computer system. We have used an IBM 486 compatible PC with 16MB main memory, 210 MB hard disk drive, 9 RS-232C port and 24 pin dot printer. The operating system and database management system were SCO UNIX and SCO foxbase, respectively. For program development, we used Xbase language provided by SCO foxbase. The C language was used for interface purpose. To make the system use friendly, pull-down menu was used. The system connected to our hospital information system via application program interface (API), so the information related to patient and request details is automatically transmitted to our computer. Our system interfaced with fwd complete blood count analyzers(Sysmex NE-8000 and Coulter STKS) for unidirectional data tansmission from analyzer to computer. The authors suggests that this system based on down-sized computer could provide a progressive approach to total LIS based on local area network, and the implemented system could serve as a model for other hospital's LIS for routine hematology. 30609 T00401030609 ^x To develop an artificial bone substitute that is gradually degraded and replaced by the regenerated natural bone, the authors designed a composite that is consisted of calcium phosphate and collagen. To use as the structural matrix of the composite, collagen was purified from human umbilical cord. The obtained collagen was treated by pepsin to remove telopeptides, and finally, the immune-free atelocollagen was produced: The cross linked atelocollagen was highly resistant to the collagenase induced collagenolysis. The cross linked collagen demonstrated an improved tensile strength. 30618 T00401030618 ^x This paper is a study on the design of adptive filter for QRS complex detection. We propose a simple adaptive algorithm to increase capability of noise cancelation in QRS complex detection with two stage adaptive filter. At the first stage, background noise is removed and at the next stage, only spectrum of QRS complex components is passed. Two adaptive filters can afford to keep track of the changes of both noise and QRS complex. Each adaptive filter consists of prediction error filter and FIR filter The impulse response of FIR filter uses coefficients of prediction error filter. The detection rates for 105 and 108 of MIT/BIH data base were 99.3% and 97.4% respectively. 30619 T00401030619 ^x To develop an artificial bone substitute that is gradually degraded and replaced by the regenerated natural bone, the authors designed and produced a composite that is consisted of calcium phosphate and collagen. Human umbilical cord origin pepsin treated type I atelocollagen was used as the structural matrix, by which sintered or non-sintered carbonate apatite was encapsulated to form an inorganic-organic composite. With cross linking atelocollagen by UV ray irradiation, the resistance to both compressive and tensile strength was increased. Collagen degradation by the collagenase induced collagenolysis was also decreased. 30620 T00401030620 ^x We have developed a monoleaflet polymer valve as an inexpensive and viable alternative, especially for short-term use in the ventricular assist device or total artificial heart. The frame and leaflet of the polymer valve were made from polyurethane, To evaluate the hemodynamic performance of the polymer valve a comparative study of flow dynamics past a polymer valve and a St. Jude Medical prosthetic valve under physiological pulsatile flow conditions in vitro was made. Comparisons between the valves were made on the transvalvular pressure drop, regurgitation volume and maximum valve opening area. The polymer valve showed smaller regurgitation volume and transvalvular pressure drop compared to the mechanical valve at higher heart rate. The results showed that the functional characteristics of the polymer valve compared favorably with those of the mechanical valve at higher heart rate. 30621 T00401030621 ^x Explosive evaporative removal process of biological tissue by absorption of a CW laser has been simulated by using gelatin and a multimode Nd:YAG laser. Because the point of maximun temperature of laser-irradiated gelatin exists below the surface due to surface cooling, evaporation at the boiling temperature is made explosively from below the surface. The important parameters of this process are the conduction loss to laser power absorption (defined as the conduction-to-laser power parameter, Nk), the convection heat transfer at the surface to conduction loss (defined as Bi), dimensionless extinction coefficient (defined as Br.), and dimensionless irradiation time (defined as Fo). Dependence of Fo on Nk and Bi has been observed by experiment, and the results have been compared with the numerical results obtained by solving a 2-dimensional conduction equation. Fo and explosion depth (from the surface to the point of maximun temperature) are increased when Nk and Bi are increased.To find out the minimum laser power for explosive evaporative removal process, steady state analysis has been also made. The limit of Nk to induce evaporative removal, which is proportional to the inverse of the laser power, has been obtained. 30622 T00401030622 ^x N1 and N2 gross neural action potentials were measured from the round window of the guinea pig cochlea at the onset of the acoustic stimuli. N1-N2 audiograms were made by means of regulating stimulant intensities in order to produce constant N1-N2 potentials as criteria for different input tone pip frequencies. The lowest threshold was measured with an input tone pip I5 dB SPL in intensity and 12 KHz in frequency when the animal was in normal physiological condition. The procedure of experimental measurements is explained in detail. This experimental approach is very useful for the investigation of the Cochlear function. Both noN1inear and active functions of the Cochlea can be monitored by N1-N2 audiograms. 30623 T00401030623 ^x In electrical impedance tomography(EIT), we use boundary current and voltage measurements toprovide the information about the cross-sectional distribution of electrical impedance or resistivity. One of the major problems in EIT has been the inaccessibility of internal voltage or current data in finding the internal impedance values. We propose a new image reconstruction method using internal current density data measured by NMR. We obtained a two-dimensional current density distribution within a phantom by processing the real and imaginary MR images from a 4.77 NMR machine. We implemented a resistivity mage reconstruction algorithm using the finite element method and sensitivity matrix. We presented computer simulation results of the mage reconstruction algorithm and furture direction of the research. 30624 T00401030624 ^x A new method of digital image analysis technique for discrimination of cancer cell was presented in this paper. The object image was the Thyroid eland cells image that was diagnosed as normal and abnormal (two types of abnormal: follicular neoplastic cell, and papillary neoplastic cell), respectively. By using the proposed region segmentation algorithm, the cells were segmented into nucleus. The 16 feature parameters were used to calculate the features of each nucleus. A9 a consequence of using dominant feature parameters method proposed in this paper, discrimination rate of 91.11% was obtained for Thyroid Gland cells. 30625 T00401030625 ^x An electrical stimulator was designed to induce locomotion for paraplegic patients caused by central nervous system injury. Optimal stimulus parameters, which can minimize muscle fatigue and can achieve effective muscle contraction were determined in slow and fast muscles in Sprague-Dawley rats. Stimulus patterns of our stimulator were designed to simulate electromyographic activity monitored during locomotion of normal subjects. Muscle types of the lower extremity were classified according to their mechanical property of contraction, which are slow muscle (msoleus m.) and fast muscle (medial gastrocneminus m., rectus femoris m., vastus lateralis m.). Optimal parameters of electrical stimulation for slow muscles were 20 Hz, 0.2 ms square pulse. For fast muscle, 40 Hz, 0.3 ms square pulse was optimal to produce repeated contraction. Higher stimulus intensity was required when synergistic muscles were stimulated simultaneously than when they were stimulated individually. Electrical stimulation for each muscle was designed to generate bipedal locomotion, so that individual muscles alternate contraction and relaxation to simulate stance and swing phases. Portable electrical stimulator with 16 channels built in microprocessor was constructed and applied to paraplegic patients due to lumbar cord injury. The electrical stimulator restored partially gait function in paraplegic patients. 30626 T00401030626 ^x Two-Dimensional modelling of the Cochlear biomechanics is presented in this paper. The Laplace partial differential equation which represents the fluid mechanics of the Cochlea has been transformed into two-dimensional electrical transmission line. The procedure of this transformation is explained in detail. The comparison between one and two dimensional models is also presented. This electrical modelling of the basilar membrane (BM) is clearly useful for the next approach to the further. Development of active elements which are essential in the producing of the sharp tuning of the BM. This paper shows that two-dimension model is qualitatively better than one-dimensional model both in amplitude and phase responses of the BM displacement. The present model is only for frequency response. However because the model is electrical, the two-dimensional transmission line model can be extended to time response without any difficult. 30627 T00401030627 ^x A method has been proposed for the fully automatic detection of left ventricular endocardial boundary in 2D short axis echocardiogram using geometric model. The procedure has the following three distinct stages. First, the initial center is estimated by the initial center estimation algorithm which is applied to decimated image. Second, the center estimation algorithm is applied to original image and then best-fit elliptic model estimation is processed. Third, best-fit boundary is detected by the cost function which is based on the best-fit elliptic model. The proposed method shows effective result without manual intervention by a human operator. 30628 T00401030628 ^x The intelligent trajectory control method that controls moving direction and average velocity for a prosthetic arm is proposed by pattern recognition and force estimations using EMG signals. Also, we propose the real time trajectory planning method which generates continuous accelleration paths using 3 stage linear filters to minimize the impact to human body induced by arm motions and to reduce the muscle fatigue. We use combination of MLP and fuzzy filter for pattern recognition to estimate the direction of a muscle and Hogan's method for the force estimation. EMG signals are acquired by using a amputation simulator and 2 dimensional joystick motion. The simulation results of proposed prosthetic arm control system using the EMf signals show that the arm is effectively followed the desired trajectory depended on estimated force and direction of muscle movements. 30638 T00401030638 ^x A new neural network architecture for the recognition of patterns from images is proposed, which is partially based on the results of physiological studies. The proposed network is composed of multi-layers and the nerve cells in each layer are connected by spatial filters which approximate receptive fields in optic nerve fields. In the proposed method, patterns recognition for complicated images is carried out using global features as well as local features such as lines and end-points. A new generating method of matched filers representing global features is proposed in this network. 30659 T00401030659 ^x An implementation scheme of the magnetic nerve stimulator using a switching mode power supply is proposed. By using a switching mode power supply rather than a conventional linear power supply for charging high voltage capacitors, the weight and size of the magnetic nerve stimulator can be considerably reduced. Maximum output voltage of the developed magnetic nerve stimulator using the switching mode power supply is 3, 000 volts and switching time is about 100 msec. Experimental results or human nerve stimulations using the developed stimulator are presented. 30768 T00401030768 ^x In this paper, we describe the design methodology and specifications of the developed module-based bedside monitors for patient monitoring. The bedside monitor consists of a main unit and module cases with various parameter modules. The main unit includes a 12.1" TFT color LCD, a main CPU board, and peripherals such as a module controller, Ethernet LAN card, video card, rotate/push button controller, etc. The main unit can connect at maximum three module cases each of which can accommodate up to 7 parameter modules. They include the modules for electrocardiograph, respiration, invasive blood pressure, noninvasive blood pressure, temperature, and SpO2 with Plethysmograph.SpO2 with Plethysmograph.