산업단지 및 일반생활 지역의 공기 중 톨루엔에 대한 개인노출 및 생체시료의 상관성 분석

이병준(Byoungjun Lee),허 정(Jung Heo),정다영(Dayoung Jung),김순신(Sunshin Kim),류현수(Hyeon-Su Ryu),최민지(Min-Ji Choi),솨이지엔페이(Jian-Fei Shuai),임성국(Sung-Guk Im),양원호(Wonho Yang) 한국환경보건학회 2017 한국환경보건학회지 Vol.43 No.4

Objectives: The purpose of this study was to assess the correlation relationship between personal exposure and urinary hippuric acid in biological monitoring for airborne toluene in an industrial complex and in general environments. Methods: Personal exposure to toluene and its metabolite, hippuric acid, in urine were simultaneously measured in occupational environments area near an industrial complex and in general environments. The study subjects were divided into three types: 137 workers who use organic solvents in the workplace, 210 residents living near a dyeing industrial complex, and 379 residents living in general environments. The toluene exposures of workers and residents were measured by a passive sampler for four days. The urine of participants was sampled when the passive samplers of personal exposure were collected. Results: The toluene and hippuric acid concentrations of workers were the highest, followed by the concentrations of residents living near a dyeing industrial complex and residents living in general environments. The coefficient of correlation between the concentrations of toluene and hippuric acid among workers was 0.749 (p<0.01) in the workplace. On the contrary, correlations between the concentrations of toluene and hippuric acid among residents living near a dyeing industrial complex and residents living in general environments were all not significant. The relationship between the concentrations of hippuric acid and toluene in three types could be described by the exponential growth model. Conclusions: This study analyzed the relationships between toluene exposure and the concentrations of hippuric acid in urine in high, middle, and low exposure environments, and could be described by the exponential growth model.

Azathioprine에 반응을 보인 류마티양 관절염에 의한 경막염(Pachymeningitis)1예

배광봉,이정호,이정찬,곽상혁,강정현,김철희,김현수,김종숙,조덕연,김삼용 충남대학교 의과대학 지역사회의학연구소 1999 충남의대잡지 Vol.26 No.1

Rheumatoid arthritis frequently involves the cervical spine and may lead to neurologic impairement. However, direct involvement of CNS structures by inflammatory cells has been reported infrequently. The prevalence of this complication of rheumatoid arthritis is unknown. Inflammatory CNS involvement in rheumatoid arthritis reportedly occurs in the setting of longstanding, active, erosive articular disease and is accompanied by extracranial and extraspinal nodules and vasculitis. This is diagnosed by radiologic finding of CNS nodules or meningeal thickening and by biopsy or autopsy. Treatment with corticosteroid, cytotoxic agent or surgical decompression is helpful. But the majority of patients die within several months of onset of neurologic symptom. Recently, we experienced a case of pachymeningitis caused by rheumatoid arthritis, which resolved repeatedly with azathioprine treatment.

췌장염에 의한 가성낭종내에 생긴 가성동맥류 : 1례 보고

오연희,이채경,김승현,이성우,양창현,이정호,이영현 동국대학교 경주대학 1996 東國論集 Vol.15 No.-

만성 췌장염의 합병증으로 생긴 가성동맥류는 드문질환으로, 반복적으로 다량의 출혈을 일으킬 수 있으며, 치료를 하지 않을 경우 사망율이 높기 때문에, 조기 진단과 치료가 필수적이다. 저자들은 38세 남자 환자에서 췌장염의 합병증으로 생긴 가성낭종내에서 발생한 가성동맥류 1예를 경험하였기에 보고하는 바이다. 가성 동맥류의 색혈류도플러상 낭종내에 양방향 흐름의 와류를 볼 수 있었다. Pancreatic Pseudoaneurysm within Pseudocyst from Pancreatitis: 1 Case Department of Diagnostic Radiology and Internal Medicine, College of Medicine,DongGuk University Yeon Hee OH M.D., Chae Kyeong Lee M.D., Seoung Hyeon Kim M.D., Sung Woo Lee M.D., Chang Heon Yang M.D., Jung Ho Lee M.D., Young Hyun Lee M.D. Pseudoaneurysm from pancreatitis is uncommon, but it can cause recurrent and massive hemorrhage. Because of high morbidity and mortality, early detection and treatment of the pseudoaneurysm is needed. We report a case of pseudoaneurysm within pseudocyst from pancreatitis. Color-flow Doppler sonography shows bidirectional flow and turbulent arterial flow, within anechoic mass.

정조(正祖) 초장지(初葬地) 출토 옥의 과학적 분석 및 보존처리

이태종,오정현,김사덕,이정민,Lee, Tae-jong,Oh, Jung-hyeon,Kim, Sa-dug,Lee, Jung-min 국립문화재연구원 2013 헤리티지:역사와 과학 Vol.46 No.4

This research aims to understand the precise character of relics based on literature search and material analysis of the jade excavated from the first buried place of King Jung-jo, and to assess the level of damage through non-destructive diagnosis. Furthermore, scientific conservation treatment was used to restore the original shape of the excavated jade. According to literature search, the excavated jade is known to be jasper, but material analysis showed that it was as a serpentine with the mineral composition of antigorite. Infrared thermography analysis to assess deterioration showed that the internal damage is the result of the interstices developed along the boundary surface of the obtained jade. For conservation treatment of the damaged area on the surface, the jade was filled with a mixture of plaster and glue, and covered with a mixture of acrylic paint and gloss medium for protection, and color was adjusted. 본 연구는 정조 초장지에서 출토된 옥에 대한 문헌조사와 재질분석을 통해 유물의 재질 특성을 밝히고 비파괴진단을 통해 출토 옥의 손상도를 평가하였다. 또한 과학적 보존처리를 실시하여 출토 옥의 원형을 복원하였다. 문헌조사 결과 출토 옥은 벽옥으로 알려졌으나 재질분석 결과, 출토 옥은 안티고라이트(Antigorite) 광물조성의 사문암으로 판단된다. 열화상분석 등 손상도 평가 결과 내부손상 부분은 포획물의 경계면을 따라 발달한 간극에 의한 것으로 나타난다. 표면손상 부분의 보존처리는 석고와 아교를 혼합하여 충전하였으며 보존처리용 아크릴물감과 그로스미디엄을 혼합한 후 색맞춤하였다.

올레산의 비율에 따른 아데노신의 경피 투과의 영향

남현빈,정세진,구민석,오예진,김용민,이훈희,윤수정,임정균 순천향대학교 부설 산업기술연구소 2021 순천향 산업기술연구소논문집 Vol.27 No.2

In addition to the development of functional cosmetics, technology to increase percutaneous absorption rate when applied to the skin is an important task. In this experiment, oleic acid was used as a skin absorption promoter, and its effect on transdermal permeability of adenosine was studied and analyzed using a skin-like membrane. As a result of the experiment, it was investigated that the permeability coefficient and concentration of adenosine are proportional to the content of oleic acid. This indicates that a high proportion of oleic acid is effective as a skin absorption promoter.

자폐스펙트럼 장애아동의 의사소통 기술 향상에 관한 단일대상연구의 문헌 분석

정유진,윤현숙 이화여자대학교 특수교육연구소 2014 특수교육 Vol.13 No.1

이 연구는 2007년부터 2013년까지 이루어진 자폐스펙트럼 장애아동의 의사소통 기술 향상을 위한 연구들을 조사하여, 일반적인 특징과 동향을 알아보고, 단일대상연구 증거기반 실제(evidence-based practices: EBP)의 기준이 되는 Horner 등(2005)이 제안한 질적 지표를 기초로 중재방법에 대한 문헌 분석을 실시하였다. 연구 결과, 첫째, 자폐스펙트럼 장애아동의 의사소통 기술 향상을 위한 단일대상연구들의 일반적인 특징을 분석한 결과, 연구대상 측면에서는 3명 이상으로 실시된 연구들이 절반 이상이었고, 연령은 주로 초등연령에서 이루어져 왔으며, 장애정도는 경증-중간 자폐에서부터 중도 자폐에 이르기까지 고르게 이루어져 왔다. 연구환경은 여러 기타 외부 환경에서 이루어진 연구들이 절반을 차지하였고, 실험설계는 주로 중다 기초선 설계와 중다 간헐 기초선 설계를 많이 사용했다. 독립변인으로는 다양한 중재방법들이 사용되었으며, 이 중 4편 이상의 논문에서 실시된 중재로는 상황이야기 중재, 보완대체 의사소통 중재가 있었다. 다음으로 종속변인으로는 의사소통 기능 증진의 효과를 본 연구들이 절반 이상을 차지하였다. 둘째, 자폐스펙트럼 장애아동의 의사소통 기술 향상을 위한 단일 대상연구들의 증거기반 실제의 기준이 되는 질적 지표 충족 정도를 살펴본 결과, 질적 지표의 영역별 평균 충족률은 종속변인 96%, 기초선 94%, 대상자 및 환경 91%, 실험통제 및 내적 타당도 91%, 독립변인 78%, 사회적 타당도 64%, 외적 타당도 62% 순으로 나타났다. 또한 각 논문별로 질적 지표의 충족여부를 살펴본 결과 21가지 질적 지표 중 90%에 해당되는 19가지의 질적 지표를 모두 충족시키는 경우는 6편(23%)인 것으로 나타났다. In this study, we investigated literatures done through 2007 to 2013 about the improvement of communication skill in children with autism spectrum disorder. We examined general feature and trends, and performed qualitative analysis based on quality indicator which can be a standard for evidence-based practice(EBP) in single subject research suggested by Horner et al.(2005). In the view of general feature and trends, we first found that more than half studies were performed with three or more children in terms of subject of study, and mainly carried out in the age before 13. Severity of disability was identified evenly from mild and moderate to severe autism. From the side of research environment, more than half studies were performed in many different environments, mostly using multiple baseline design and multiple probe design. Various interventions were conducted as independent variable. Social stories intervention and augmentative and alternative communication intervention(AAC) were employed in more than 4 literatures. In dependent variable, it was confirmed that more that half of studies showed the significant improvement in communication skill. In the analysis of satisfaction level in quality indicator, the average level of areal satisfaction in quality indicator was respectively 96% in dependent variable, 94% in baseline, 91% in subjects and environments, 91% in experimental control/internal validity, 78% in independent variable, 64% in social validity, and 62% in external validity. Besides, among all literatures examined by satisfaction level in quality indicator, 6 literatures (23%) fulfilled the requirements of 19 out of 21 quality indicators.

조선업 용접공의 용접흄 생애누적노출량을 이용한 환기기능 평가

정춘화,임현우,구정완,박정일 大韓産業醫學會 2002 대한직업환경의학회지 Vol.14 No.4

목적 : 조선업 용접공들의 용접흄 생애 누적노출량을 이용하여 그들의 환기기능을 평가하기 위하여 본연구를 실시하였다. 방법 : 1개 대규모 조선소에서 용접흠에 5년이상 노출된 남자근로자 241명과 대조군으로 사무직 남자 근로자 80명을 대상으로 개인별 생애 누적노출량을 산출하였고 환기기능으로서 노력성폐활량(FVC), 1초량(FEV_1), 1초율(FEV_1%), 최대중간호기 속도(MMF), 최고호기기류속도(PEER)와 호기 FVC의 50%, 75% 시점에서의 최대호기기류인 FEF_50, FEF_75를 얻고저 노력성 호기곡선과 최대호기기류-용량곡선을 측정하여 분석한 결과는 다음과 같았다. 결과 : FEF_50과 FEF_75의 예측치에 대한 백분율(%pred)의 평균은 노출군이 대조군보다 유의하게 감소하였고 MMF는 감소하는 경향을 보였다. 현재의 노출수준 증가에 따라 감소하는 유의한 환기지수는 없었다. 환기지수 중 MMF, FEF_50 및 FEF_75는 노출 기간이 길수록 유의하게 감소하였다. 노출수준×노출기간으로 산출한 용접흄 누적노출량(C1)이 증가함에 따라 최대노출군에서 유의하게 감소한 환기지수는 FEF_75 뿐이었다. 노출수준, 노출기간, 환기시설, 생산량, 보호구사용, 용접봉 및 와이어 종류 등의 변수들을 고려하여 산출한 용접흠 누적 노출량(C2)이 증가함에 따라 최대노출군에서 유의하게 감소한 환기지수는 FEF_75이었으며 MMF 및 FEF_50은 감소하는 경향을 보였다. 또한 환기지수중 MMF, FEF_50 및 FEF_75의 경우 생애 누적노출량(C2)이 증가함에 따라 비정상적인 환기기능을 보인 근로자 비율이 유의하게 증가하였다. 결론 : 본 연구결과는 노출 관련 요인들을 고려하여 산출한 생애 누적노출량(C2)을 이용하여 용접흠에 노출된 근로자들의 환기기능을 평가하는데 있어서 MMF, FEF_50 및 FEF_75가 유용한 지수이었다. Objectives : This study was conducted to evaluate the ventilatory function in shipyard welders using the lifetime cumulative exposure to welding fumes. Methods : Ventilatory function tests were performed on 241 male welders at one large shipuad. exposed to welding fumes for over five years, and was compared to 80 male control subjects. Ventilatory function indices, such as forced vital capacity(FVC). one-second forced expiratory volume(FEV), rato of FEV_1 to FVC(FEV_1%), maximal mid-expira-tory flow(MMF). peak expiratory flow rate(PEER) and maximal expiratory flow at 50 and 75% of expited FVC(FEF_50 and FEF_75), were obtained by analuyzing forced expiratory spirograms and maximal expiratory flowvolume curves that were simultaneously mea-sured by an Impulse ocillometry(IOS) program in the standing position. Results : FEF_50 and FEF_75 expressed as a percentage of the predicted values were significatly lower in the exposure group than in the controls, and the MMF tended to decrease. The mens of all the ventilatory indices, expressed as percentage of the predicted values, were not significantly increased at the current exposure levels. The MMF, FEF_+50 and FEF_75, expressed as a percentage of the predicted values, were significantly decreased with an increase in exposure duration. Onlu the FEF_75, expressed as a percentage of the predicted value, was significantly decreased with an increase in the cunulative exposure to welding fumes(C1). The FEF_75, expressed as a percentage of the predicted value, was significantly decreased with an increase in the cumulative exposure to welding fumes(C2), The above parameters were calculated to consider the durrent exposure level, exposure duration, application of the ventilator sustem, production rate, personal protection device, electrode and swelding wire. The MMF and FDF_50, expressed as a percentage of the predicted value, tended to decrease, The proportion of workers with abnormal MMF, FDF_50 and FDF_75 were significantly increased with an increase in the cumulative exposure to welding fumes(C2). Conclusions : These findings suggested that the MMF, FDF_50 and FDF_75 are sensitive and practical indices for the evaluation of the ventilatory function of workeers exposed to welding fumes, when the lifetime cumulative exposure(C2) is considered as a factor affedting exposure.

측사위 경두개 촬영시 표준사진과 개인별 수정사진의 비교연구

정경용,이기헌,황현식 대한치과교정학회 1993 대한치과교정학회지 Vol.23 No.3

Among the radiographs for temporomandibular joint, transcranial radiograph is widely used for screening and diagnosing temporomandibular disorder because it has sharp image and it is easy to take. This study was performed to compare condylar position and image sarpness in standard and individually corrected transcranial radiographs using Accurad-200 headholder. Submentovertex view, Reverse-Towne view, Standard and individually corrected transcranial radiographs of 45 university students who were randomly selected were traced, measured and analyzed. The results were as follows : 1. The means of condylar axes and lateral slopes were 16.8˚ and 22.5˚ respectively. There were no differences between male and female or right and left side. 2. Individually corrected radiographs showed smaller posterior joint space and larger anterior joint space than standard radiographs, but superior joint space did not show a statistical difference between standard and individually corrected radiographs. 3. While a large number(42.2% ) of the standard radiographs showed concentric condylar position, lots of(57.8) condylar positions were retropositioned in the individually corrected radiographs. 4. The image sharpness was inferior in the individually corrected radiographs to that of the standard radiographs.

EFFECT OF RESTORATION TYPE ON THE STRESS DISTRIBUTION OF ENDODONTICALLY TREATED MAXILLARY PREMOLARS : THREE-DIMENSIONAL FINITE ELEMENT STUDY

정현숙,김현철,허복,김광훈,손권,박정길 대한치과보존학회 2009 Restorative Dentistry & Endodontics Vol.34 No.1

본 연구의 목적은 다양한 교합하중 조건하에서 아말감, 복합레진, 세라믹 인레이, 그리고 금 인레이로 수복한 근관 치료된 상악 제2소구치의 응력분포를 3차원 유한요소법으로 분석하는 것이다. 발치된 상악 제2소구치를 이용하여 근관 치료된 3차원 유한요소모형을 제작하였다. 제작된 소구치 모형의 근관와동을 위 4가지 재료로 각각 수복한 후, 협측교두 (Load-1) 또는 설측교두 (Load-2)에 500 N의 하중을, 설측교두와 근심변연에 총 170 N의 하중 (Load-3)을 가하였다. 세 가지의 하중조건 하에서 각 수복물에 따른 협측과 설측의 치경부 그리고 교합면의 정중구에서 나타나는 인장응력의 분포양상을 ANSYS 프로그램으로 분석하여 다음과 같은 결과를 얻었다. 1.모든 수복물의 경우에서 Load-1에서는 설측의 치경부, Load-2에서는 협측의 치경부에서 높은 응력이 관찰되었고, 수복물 종류에 따른 차이는 관찰되지 않았다. 2.모든 수복물의 경우에서 교합면의 하중점 근처와 정중구를 따라 높은 응력이 관찰되었고, 수복물 종류에 따라 약간 의 차이가 관찰되었다. 3.모든 수복물의 경우에서 Load-3에서는 하중점 근처에서 높은 응력이 관찰되었고, 수복물 종류에 따른 차이는 관찰되지 않았다. The purpose of this study was to investigate the effects of four restorative materials under various oclusal loading conditions on the stress distribution at the CEJ of buccal. palatal surface and central groove of occlusal surface of endodontically treated maxillary second premolar, using a 3D finte element analysis A 3D finite element model of human maxillary second premolar was endodontically treated. After endodontic treatment, access cavity was filled with Amalgam, resin, ceramic or gold of different mechanical properties A static 500N forces were applied at the buccal (Load-1) and palatal cusp (Load-2) and a static 170N forces were applied at the mesial marginal ridge and palatal cusp simultaneously as centric occlusion (Load-3). Under 3-type Loading condition, the value of tensile stress was analyzed after 4-type restoration at the CEJ of buccal and palatal surface and central groove of occlusal surface Excessive high tensile stresses were observed along the palatal CEJ in Load-1 case and buccal CEJ in Load-2 in all of the restorations. There was no difference in magnitude of stress in relation to the type of restorations. Heavy tensile stress concentrations were observed around the loading point and along the central groove of occlusal surface in all of the restorations. There was slight difference in magnitude of stress between different types of restorations. High tensile stress concentrations around the loading points were observed and there was no difference in magnitude of stress between different types of restorations in Load- 3.

영상신호의 상관관계를 이용한 CORDIC 기반의 DCT 설계

정현욱,김진상,조원경 경희-다반 ASIC 설계교육센터 2002 경희-다반 ASIC센터 논문집 Vol.3 No.-

We propose a novel low-power discrete cosine transform (DCT) architecture based on CORDIC processors. The CORDIC-based DCT algorithm is a good candidate for high performance applications because of its simple arithmetic operation. The proposed algorithm reduces conventional CORDIC-based DCT computation by exploiting the spatial correlation of image data. The proposed architecture can be used for the low-power applications like multimedia portable electronic devices.