"Dice와 fill" 방식을 이용한 1-3 압전복합재의 제조와 횡방향 단위 크기에 따른 압전특성 평가

김영덕,김광일,정우철,김흥락,김동수 한국비파괴검사학회 2002 한국비파괴검사학회지 Vol.22 No.4

NDT나 의료용 영상장치에 응용되는 압전복합체는 일반적인 세라믹이나 고분자 압전재료에 비하여 많은 장점을 가진다. 이들 응용분야에서는 전기기계결합게수가 높아야 하고, 음향임피던스가 낮아야 한다. 그러나, 압전복합제의 횡방향 단위 크기가 조밀하지 못한 경우 횡방향으로 전행하는 판파에 의한 불필요한 진동이 표면에 발생하게 된다. 횡방향 단위 크기와 세라믹 체적비에 따른 압전 특성을 조사하기 위하여 PMN-PZT 세라믹과 Epofix 에폭시로 에폭시의 폭을 달리하면서 1-3 형 압전복합체를 제작하였다. 제작된 1-3형 압전복합체의 두께방향 진동모드의 전기기계결합계수, 음향임피던스는 각각 0.36~0.64, 9.8~22.7 MRayl로 나타났으며, 횡방향 단위크기가 줄어들수록 횡방향 모드 공진 주파수가 증가하였다. The piezoelectric composites had many adventages in comparison qith conventional piezoelectric ceramics and piezopolymers for ultrasonic transducers used in NDT and in medical ultrasonic imaging. The electromechanical coupling coeffucient should be high and the acoustic impedance should be low in these applications. However, the cross-coupling with spurious oscillations caused lateral spatial scale. The thickness mode electomechanical coupling coefficient of 1-3 type of piezoelectric composites were 0.36 to 0.64, and the acoustic impedance of them were 9.8 to 22.7 MRayl. The lateral resonance frequency of 1-3 type piezoelectric composites shifted to high frequency region with decreasing lateral spatial scale.

2003년 국내 중증급성호흡기증후군 진료 현황 및 문제점 분석

이진수,김은실,정문현,백제중,정선화,안주희,최영화,이선희,고철우,김성범,김민자,박승철,기현균,송재훈,최상호,김양수,이상오,조용균,박영훈,정숙인,김연숙,이흥범,손창희,장성희,정희진,김우주 대한감염학회 2004 감염과 화학요법 Vol.36 No.3

목적 : 2002년 말 중국에서 SARS가 발생한 이후 국내에서도 2003년 10월까지 총 3명의 추정환자, 17명의 의심환자가 보고되었다. 향후 추가적인 SARS의 유행이 우려되는 상황에서, 그간의 SARS 환자 진료에 있어서의 실질적인 준비사항, 진료 현황 등에 대한 조사를 통해 문제점을 파악하여, 향후 더 나은 대비가 될 수 있도록 개선점을 제시하고자 하였다. 재료 및 방법 : SARS로 의심되는 환자를 진료 경험이 있는 병원의료진을 대상으로 2003년 10월에 설문조사를 실시하였다. 설문에는 SARS 환자 진료 시의 실질적인 조치, 진료 현황, 병실, 응급실 및 외래에서의 격리 시설과 준비사항, 보건당국의 관리와 지원에 관한 사항을 포함하였다. 결과 : 대상이 되는 22개 병원 중 17개(17/22, 77.2%) 병원이 설문에 응하였다. SARS 환자를 위한 격리실은 응급실, 외래, 일반병실 및 중환자실에서 각각 9개(9/17, 52.9%), 5개(5/17, 29.4%), 15개(15/16, 93.7%), 4개(4/16, 25%) 병원에서 음압처리가 되어있지 않은 일인실 혹은 다인실이 사용되었고, 1개(1/16, 6.3%) 병원에서만 일반병실에서 음압격리실이 운영되었다. 입원환자의 진찰 시 개인보호구의 착용은 거의 모든 의료기관에서 이루어졌다. 보건당국에서 SARS지정병원의 시설 등을 사전에 확인한 곳은 1곳(1/12, 8.3%)이였고, 14개 병원(14/15, 93.3%)에서는 보건당국에 의뢰한 검사결과를 통하 받지 못하였다. 결론 : 의료기관에서 SARS 환자용 격리실뿐만 아니라 기존의 격리실 설비 등이 미흡하였으며, 특히 중환자실 및 외래의 준비가 더욱 부족하였다. 보건당국의 의료기관에 대한 종합적인 지원이 부족하였고, 병원과의 원활한 연계가 잘 이루어지지 않았다. SARS 만이 아닌 격리를 필요로 하는 질환의 적절한 진료를 위해 향후 병원 시설의 정비와 정부차원에서의 보다 구체적이고 실질적인 대책마련이 필요하다. Background : There was an worldwide outbreak of the Severe Acute Respiratory Syndrome (SARS) originated from China in late 2002. During that period three cases of suspected SARS and 17 cases of probable SARS were reported in Korea. With the concerns about the reemergence of SARS-coV transmission, it is important to be prepared for any possibility. So, this study is aimed to analysis the past measures in managing SARS and propose the amendatory plans to improve the preparedness. Materials & Methods : Questionnaires were collected among clinicians with any experience in managing the probable or suspected SARS cases in Oct. 2003. 17 out of 22 hospitals responded to the questionnaire. The contents in the questionnaire were practical activities, personal equipments, response plans, isolation facilities in emergency centers, outpatient clinics, general wards and intensive care units, and relationship with the public health department. Results : The dedicated isolation rooms in emergency centers, outpatient clinics, general wards, and intensive care units were prepared in 9 (9/17, 52.9%), 5 (5/17, 29.4%), 15 (15/16, 93.7%), and 4 (4/16, 25.0%) hospitals, respectively. Except for one hospital that newly made negative pressure room for SARS, single or multi-bed rooms without airborne infection control were used in all the other hospitals. The personal precaution principles were kept quite well in general wards. Before the designation of SARS hospital by the public health department prior evalution to see if the hospital was suitable for managing SARS was conducted in only 1 (1/12, 8.3%) hospital. The results of laboratory diagnosis were reported back in 1 (1/15, 6.6%) hospital. Conclusions : The isolation facilities which can control airborne infection were almost deficient not only for SARS but also for other respiratory transmissible diseases. For the infection control of transmissible diseases including SARS, more investment is needed on medical facilities and comprehensive support from the public health department required.

단무지 공장에서 발생한 질식 사고의 원인과 방사선학적 소견: 중례보고 및 가스분석 결과

박충기,김만구,김흥철,안범규,박만수,황우철,최철순,강익원 江原大學校 附設 環境硏究所 1994 環境硏究 Vol.11 No.-

목 적:단무지 공장에서 질식사고를 일으켰던 가스의 종류를 알아내고, 이러한 가스중독의 방서선학적 소견을 소개하기 위하여 본 연구를 하였다. 대상 및 방법:단무지 공장에서 발생한 질식 사고자 3예중 생존자 1예를 대상으로 단순흥부X-선검사와 CT 소견을 분석하였으며, 가스의 종류를 알아내기 위하여 단무지를 유리병에 넣어 발생된 가스를 가스크로마토그래픽을 이용하여 분석하였다. 결 과:단무지 공장에서 발생한 질식사고자중 생존한 1명의 방사선학적 검사에서 신속히 호전되는 폐경결(consolidation)을 볼 수 있었으며 이는 폐부종의 소견임을 알 수 있었다. 협기성 상태에서 단무지를 담은 유리병의 상층부 가스를 실험 분석한 결과 이산화탄소, 에칠알코올이 다량으로 검출되었으나 독성가스는 주로 황화수소이였다. 결 론:단무지 공장의 질식 사고자에서 폐방사선학적 소견은 폐경결을 보이는 폐부증으로서 이는 실험을 통해 단무지에서 발생되는 유독가스인 황화수소 때문임을 입증하였다. Purpose: To identify the main toxic gas released from salted radish in rice bran(Dan-M-Ji) and to introduce the radiological findings of the patient who was exposed to the gas. Materials and Methods: Chest radiographs and CT scans of one survivor among three men who were exposed to the gas from Dan-Mu-Ji were reviewed. Gas obtained from the closed bottle containing Dan-Mu-Ji was analized by using the gas chromatography. Results: The radiographlc examinations of the survivor were suggestive of pulmonary edema with it's rapidly improving consolidations in both lung. The headapace gas within the bottle containing Dan-Mu-Ji was mainly composed with carbon dioxide, ethyl alcohol and hydrogen sulfide, of which hydrogen sulfide was considered the main toxic gas released. Conclusion: Under the anaerobic condition, Dan-Mu-Ji released toxic hydrogen sulfide. Inhalation of hydrogen sulfide might produce non-cardiogenic pulmonary edema.

유치 치근단 염증에 의한 계승치 맹출장애의 일예

김철훈,임두영,황인성,손홍규,최돈옥 大韓小兒齒科學會 1982 大韓小兒齒科學會誌 Vol.9 No.1

This is a case report of difficult eruption of succeeding permanent tooth by periapical inflammation of primary tooth. 12-year-8-month-old girl who had been treated by pulpotomy of lower right second primary molar about 4 years ago was recalled for prolonged retention of it. Radiographs showed periapical inflammation of lower right second primary molar and horizontal buccal impaction of succeeding permanent tooth. Right second premolar seemed impossible to erupt so surgical extraction of it was done with removal of lower right second primary molar and resin space maintainer was manipulated for prevention of space closure and elongation of opposing tooth.

감꼭지나방(나비목:감꼭지나방과)의 발육생태

김정화,김길하,조수원,박은철,박형진 충북대학교 첨단원예기술개발연구센터 2000 연구보고서 Vol.5 No.-

충북 영동의 감나무 가로수에서 감꼭지나방(Stathmopoda masinissa)을 채집하여 온도 25±1℃,광주기 16L:8D, 상대습도 85%의 실내조건에서 이들의 발육생태를 조사하였다. 각 충태별 발육일수는 알기간 7.4일, 유충기간 34.8일, 번데기기간이 15.5일이었다. 1령에서 5령의 영기간은 각각 3.5일, 4.2일, 5.2일, 6.5일, 15.4일이었으며, 유충의 두폭은 각각 0.20, 0.40, 0.65, 0.87, 1.07mm이었다. 용화율과 우화율은 각각 68.0%, 59.9%이었다. 성충 수명은 수컷이 6.2일, 암컷이 10.1일이며, 암컷 한 마리당 평균 산란수는 24.4개였다. Persimmon fruit moth, Sathmopoda masinissa, collected from roadside persimmon trees planted as shade trees in yeongdong area was used to investigate their developmental ecology under laboratory condition; 25±1℃, 16L : 8D and 85% RH. Developmental periods for eggs, larvae, and pupae were 7.4, 34.8 and 15.5 days, respectively. The duration for each larval instar from the 1st to the 5th was 3.5, 4.2, 5.2, 6.5 and 15.4 days, respectively, and the head capsule width of corresponding stage was 0.20, 0.40, 0.65, 0.87 and 1.07mm. Rates of pupation and emergence were 68.0 and 59.9%, respectively. Longevity of adult males was 6.3 days while that of females was 10.1 days. Average fecundity was 25.4 eggs.

화상 환자에서 발생한 외과적 중재술을 요하는 감염성 심내막염 2예

김근숙,이태유,정연손,최창순,최민호,류제헌,김철홍,조구영,우흥정 대한감염학회 2003 감염과 화학요법 Vol.35 No.3

감염성 심내막염은 화상 후에 발생할 수 있는 치명적인 합병증이다. 임상 증상은 일반적으로 없는 경우가 대부분이고 지속되는 발열과 양성 혈액 배양 검사가 유일하다. 감염의 다른 확실한 원인 없이 발열과 양성 혈액 배양 검사가 있을 때는 감염성 심내막염을 강력하게 의심해야 하며 심장 초음파로 진단 가능하다. 감염성 심내막염은 사망률은 높지만 초기에 진단하면 항생제 정주를 지속하는 것으로 치료할 수 있다. 저자들은 화상환자에서 발생한 수술적 처치를 필요로 하는 감염성 심내막염 2예를 경험하였기에 보고하는 바이다. Infective endocarditis is a rare but fatal complication following burn injury. The clinical presentation is silent, but with persistent fever and positive blood culture. The manipulation of clinical care as well as the burn wound itself and immunosuppression caused by extensive bums puts the burn patients at risk of bacteremia. Staphylococcus aureus and Gram-negative bacilli are most common pathogens of infective endocarditis following burns. We report herein two cases of infective endocarditis in the burn patients who requires surgical intervention. The first case was caused by Pseudomonas aeruginosa with complication of multifocal pneumonia, and the second case by coagulase-negative stapylococcus with cerebral hemorrhage.

원형편파로 급전되는 포물면 반사기 안테나에서의 빔 편이현상

김한철,김흥수 濟州大學校 工科大學 産業技術硏究所 1992 産業技術硏究報告 Vol.3 No.-

The beam squint phenomenon is an important factor to design parabolic reflector antennas. This paper aims to suggest the general squint-predicting formular and squint-free condition in circularly feed paraboloidal antennas. Squint-free condition is suggested to avoid the squint phenomenon that can be affect the antenna pointing performance in the long-distance communication, deep-space telemetry, radioastronomy, etc. Squint-free antennas can be designed by this squint-free condition.

중앙안면골 골절 환자에서의 이차 비성형술

김건중,이정삼,최재선,민홍기,정종철 大韓顎顔面成形再建外科學會 1996 Maxillofacial Plastic Reconstructive Surgery Vol.18 No.4

Nasal bone fracture is common in mid-facial trauma patients. In these patients, facial bone and nasal bone fracture are reducted at same time, but definite nasal reduction is diffidulty in these patients because of nasotracheal intubation during general anesthesia and facial swelling in early facial trauma patients. If nasal packing and MMF are needed, there are difficult to maintain the reducted nasal bone because of some difficulty in airway maintenance after nasal packing and increasing the patient discomfort. So postoperative nasal deformity is more common in these combined patients. Secondary rhinoplasty is necessary in these patients who have deformed nasal bone, and there are many methods and materials for secondary rhinoplasty. But if primary nasal bone was reducted symmetrically, it is easy in secondary rhinoplasty. We present 7 cases of secondary rhinoplasty in mid-facial trauma patients who had combined nasal bone fracture. In these patients, primary nasal bone reduction carried with closed reduction method during primary facial bone reduction. About 6 months later, we performed secondary rhinoplasty with iliac bone and alloplastic materials. So we report these cases with literatures.

치수제거후 흰쥐 삼차신경절에서 VIP 면역반응세포의 변화: 공초점레이저주사현미경적 연구

김흥중,김승재,박주철,박주철,이상호 대한소아치과학회 2001 大韓小兒齒科學會誌 Vol.28 No.1

말초신경 손상에 의한 VIP의 변화를 연구하기 위해 흰쥐 하악대구치 치수제거 후 삼차신경 절에서 VIP의 분포 및 반응강도를 공초점레이저주사현미경을 이용하여 관찰하였다. 체중 200g내외의 Sprague-Dawley계 흰쥐를 대조군과 하악대구치 치수제거 후 14일군으로 분리하여 희생시켰다. 1차 항체로 rabbit anti-VIP, 2차 항체로 fluorescein isothiocyanate(FITC) conjugated anti-rabbit IgG를 사용하여 면역형광염색을 시행한 후 공초점레이저주사현미경으로 관찰하여 다음과 같은 결론을 얻었다. 1.삼차신경절 하악부위에서 VIP 양성반응세포의 비율은 대조군에서 7.40%를, 실험군에서는 28.42%를 보였다. 대조군에 비해 실험군에서 양성반응세포의 증가를 보였다. 2.삼차신경절 하악부위에서 VIP 면역반응세포체에 대한 상대성 형광강도는 대조군에서 87.78을, 실험군에서는 138.65를 보였다. 대조군과 비교하였을 때 실험군에서 상대성 형광강도의 증가를 보였다. 3.실험군의 광연속절편(1㎛) 관찰에서 VIP 면역반응세포는 9개의 절편 대부분에서 강하게 나타났다. 축삭의 면역반응을 살펴보면, 대조군의 축삭에서는 약한 반응을 보였으며, 실험군의 축삭에서는 강한 면역반응을 보였다. 또한 양성반응 세포체의 크기는 20∼25㎛의 중간 크기의 세포체에서 강한 면역반응을 보였다. 위의 결과로 보아 치수제거 후에 삼차신경절 하악부위에서 VIP면역반응세포의 증가와 함께 상대성 형광강도가 높아졌음을 알 수 있었다. The purpose of this study was to investigate the distribution and fluorescence intensity of vasoactive intestinal polypeptide immunoreactive(VIP-IR) cells in rat trigeminal ganglion following pulp extirpation of rat mandibular molar. The animals were divided into control group(n=6) and experimental group(n=6). The experimental animals were sacrificed at 14 days after pulp extirpation. The trigeminal ganglion was removed and immersed in the 4% paraformaldehyde in 0.1M phosphate buffer. Serial frozen sections about 20㎛ in thickness were cut with a cryostat The immunofluorescence staining was performed. The rabbit anti-VIP(1:8,000) was used as primary antibody and fluorescene isothiocynate(FITC) cojugated anti-rabbit IgG(1:80) as secondary antibody. The slides were observed under confocal laser scanning microscope(CLSM). Unprocessed optical sections were obtained and stored on a optical disk. Color pictures were printed by a video copy processor. The results were as follows ; 1. The positive ratio of VIP-IR cells in mandibular part of trigeminal ganglion were 7.40% in control group and 28.42% in experimental group(14 days affter pulp extirpation). 2. The relative fluorescence intensity of VIP-IR cells in mandibular part of trigeminal ganglion were 87.78 in control group and 138.65 in experimental group. The relative fluorescence intensity of experimental group was 58% higher than that of control group. 3. In optical serial section analysis of VIP-IR cells of experimental group, most of the 9 section showed high fluorescence intensity. At high magnification, axons of the experimental group displayed greater VIP-IR than in the control group, and the positive cells were mainly of medium size. The result indicate that number and fluorescence intensity of VTP-IR cells were increased in the mandibular part of trigeminal ganglion following pulp extirpation of mandibular molar, and it suggests that VIP could play a role in processing of nociception.

상아모세포 관련 유전자, OD314의 발현과 기능 연구 : OD314

김두현,김흥중,정문진,손호현,박주철 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.4

Odontoblasts are responsible for the formation and maintenance of dentin. They are known to synthesize unique gene products including dentin sialophosphoprotein (DSPP). Another unique genes of the cells remain unclear. OD314 was isolated from the odontoblasts/pulp cells of rats and partially characterized as an odonto-blast-enriched gene (Dey et al., 2001). This study aimed to elucidate the biological function of OD314, relating to odontoblast differentiation and dentinogenesis. After determining the open reading frame (ORF) of OD314 by transient transfection analysis using green fluorescent protein (GFP) expression vector, mRNA in-situ hybridization, immunohistochemistry, reverse transcription-polymerase chain reaction (RT-PCR) and western analysis were performed. The results were as follows: 1. In in-situ hybridization, OD314 mRNAs were expressed in odontoblasts of developing coronal and root pulp. 2, OD314 was a novel protein encoding 154 amino acids, and the protein was mainly expressed in cyto-plasm by transient transfection analysis. 3. Mineralized nodules were associated with multilayer cell nodules in the culture of human dental pulp cells and first detected from day 21 using alizarin-red S staining. 4. In RT-PCR analysis, OD314, osteocalcin (OC) and DSPP strongly expressed throughout 28 days of culture. Whereas, osteonectin (ON) mRNA expression stayed low up to day 14, and then gradually decreased from day 21. 5. Western blots showed an approximately 17 kDa band. OD314 protein was expressed from the start of culture and then increased greatly from day 21. In conclusion, OD314 is considered as an odontoblast-enriched gene and may play important roles in odontoblast differentiation and dentin mineralization.