4대강 유역 및 공단지역 환경 중 PFOS 및 PFOA의 잔류수준 비교평가

조천래 ( Chon Rae Cho ),엄익춘 ( Ig Chun Eom ),김은주 ( Eun Ju Kim ),김수진 ( Sue Jin Kim ),최경희 ( Kyung Hee Choi ),조현서 ( Hyeon Seo Cho ),윤준헌 ( Jun Heon Yoon ) 한국환경분석학회 2009 환경분석과 독성보건 Vol.12 No.4

PFCs are group of fluorochemicals that have been produced and used for over 50 years for various purpose including soil/stain resistance and surfactant applications. These chemicals were degraded to Perfluorooctane sulfonate (PFOS) and Perfluorooctanoic acid (PFOA) that were kinds of persistence metabolites. Previous studies showed that these chemicals can be accumulated in various environmental media. In this study, the concentration level of PFOS and PFOA were measured in 59 samples collected from 4 major river watersheds and 6 industrial complex areas in 2006 and 2007. Mean concentration of PFOS in water, sediment and soil were N.D.-1180.0 ng/L, N.D.-9.17 ng/g dry-wt. and N.D.-10.97 ng/g dry-wt. respectively. Mean concentrations of PFOA in water, sediment and soil were N.D.-13850.0 ng/L, N.D.-2.07 ng/g dry-wt. and N.D.-1.04 ng/g drywt., respectively. The concentration of PFOS in water samples were significant difference among river, industrial complex stream and waste water treatment effluent (p<0.05). But PFOA were no significant difference among those samples. These results suggested that concentration of PFOS in water was direct effected by industrial complex activities.

Interobserver and Intraobserver Reliability of Sub-Axial Injury Classification and Severity Scale between Radiologist, Resident and Spine Surgeon

Lee, Woo Jin,Yoon, Seung Hwan,Kim, Yeo Ju,Kim, Ji Yong,Park, Hyung Chun,Park, Chon Oon The Korean Neurosurgical Society 2012 Journal of Korean neurosurgical society Vol.52 No.3

Objective : The sub-axial injury classification (SLIC) and severity scale was developed to decide whether to operate the cervical injured patient or not, but the reliability of SLIC and severity scale among the different physicians was not well known. Therefore, we evaluated the reliability of SLIC among a spine surgeon, a resident of neurosurgery and a neuro-radiologist. Methods : In retrograde review in single hospital from 2002 to 2009 years, 75 cases of sub-axial spine injured patients underwent operation. Each case was blindly reviewed for the SLIC and severity scale by 3 different observers by two times with 4 weeks interval with randomly allocated. The compared axis was the injury morphology score, the disco-ligamentous complex score, the neurological status score and total SLIC score; the neurological status score was derived from the review of medical record. The kappa value was used for the statistical analysis. Results : Interobserver agreement of SLIC and severity scale was substantial agreement in the score of injury morphology [intraclass correlation (ICC)=0.603] and total SLIC and severity sacle (ICC value=0.775), but was fair agreement in the disco-ligamentous complex score (ICC value= 0.304). Intraobserver agreements were almost perfect agreement in whole scales with ICC of 0.974 in a spine surgeon, 0.948 in a resident of neurosurgery, and 0.963 in a neuro-radiologist. Conclusion : The SLIC and severity scale is comprehensive and easily applicable tool in spine injured patient. Moreover, it is very useful tool to communicate among spine surgeons, residents of neurosurgery and neuro-radiologists with sufficient reproducibility.

메티실린 감수성 표피포도알균(MSSE) 각막염과 메티실린 내성 표피포도알균(MRSE) 각막염의 비교 연구

정진구,권의용,조남천,유인천,Jin Gu Jeong,Eui Young Kweon,Nam Chun Cho,In Chon You 대한안과학회 2011 대한안과학회지 Vol.52 No.8

Purpose: To investigate the clinical features and treatment outcomes between methicillin-sensitive Staphylococcus epidermidis (MSSE) and methicillin-resistant Staphylococcus epidermidis (MRSE) keratitis groups. Methods: A retrospective analysis of case series was conducted of all patients with keratitis caused only by Staphylococcus epidermidis from January 1997 through December 2008. Sex, age, history of trauma, systemic disease, previous ocular history, antibiotic sensitivity test results, and treatment outcomes were evaluated. Patients were categorized into two groups as MSSE and MRSE according to methicillin-sensitivity result, and a comparative analysis was performed. Results: There were no significant differences in clinical features, such as risk factors or size or location of keratitis between the two groups. All MSSE and MRSE isolates were sensitive to vancomycin, moxifloxacin, and levofloxacin. All MSSE and 17%, 50%, 52%, and 57% of MRSE isolates were sensitive to cephalothin, norfloxacin, ciprofloxacin, and erythromycin, respectively (p < 0.05). There was no significant difference in visual acuity between the two groups. Conclusions: All MSSE and MRSE isolates were sensitive to vancomycin and to third- or fourth-generation fluoroquinolones In addition, approximately 50% of MRSE isolates were sensitive to norfloxacin and ciprofloxacin. There were no significant differences in clinical features of keratitis caused by MSSE versus those of MRSE isolates. Both keratitis groups had relatively good visual prognoses. J Korean Ophthalmol Soc 2011;52(8):930-935

Original Articles : Genetic relationship of Campylobacter jejuni isolates from different sources by PFGE and flaA typing

( Huwang Wui Ho ),( Hee Jin Dong ),( Woo Hyun Kim ),( Ki Man Bang ),( Jae Uk An ),( Chun Hyung Kim ),( Jung Whan Chon ),( Kun Ho Seo ),( Tae Wook Hahn ),( Bok Kyung Ku ),( Seong Beom Cho ) 한국예방수의학회(구 한국수의공중보건학회) 2015 예방수의학회지 Vol.39 No.1

Abstract: Thirty-one Campylobacter jejuni isolates (22 from various local sources, 9 from imported chicken meats) weresubtyped with PFGE and flaA typing to investigate their genetic relatedness. Based on a 90% similarity criterion, 23 and 21genotypic patterns were formed by PFGE and flaA typing, respectively. The discriminatory indices for PFGE, flaA typing, anda composite analysis of PFGE and flaA typing were 0.9785, 0.9527, and 0.9871, respectively. Similar patterns in compositeanalysis were observed between sources (cattle and chicken, and cattle and human), indicating that reservoir animals mayhave been the source of human campylobacteriosis. Therefore, strict hygiene measures from farm to table should beimplemented to prevent diseases due to C. jejuni in humans.

P-q-t chart 분석기법을 이용한 그라무팅 신뢰성 향상 방안에 관한 실험적 연구

천병식,최동찬,김진춘,Chon, Byung-Sik,Choi, Dong-Chan,Kim, Jin-Chun 한국터널지하공간학회 2008 한국터널지하공간학회논문집 Vol.10 No.4

연약지반개량 기술 중의 하나인 그라우팅이 차수 보강 목적으로 다양한 건설공사에서 널리 활용되고 있지만 그라우팅공법이 지반내부에서 시행되는 기술적 특성상 그 시공과정의 적합성 및 시공 후 효과확인 방법에 대한 문제점이 많다. 본 연구 대상의 그라우팅 p-q-t chart는 주입속도(q)와 주입압(p)의 경시변화(t)에 대한 관계를 나타내는 지표로서 그라우팅 시공과정을 모니터링하여 시공인자의 적합성을 평가하여 조정할 수 있는 유일한 수단이다. 본 연구에서는 시험 및 시공과정을 일괄적으로 관리할 수 있는 자동 주입관리 시스템(AGS; automatic grouting system)를 이용하여 정밀한 p-q-t chart를 검출할 수 있었으며, 검출된 p-q-t chart의 유형을 표준유형과 비교분석을 통해서 대상지반의 주입특성에 대한 정보를 추정할 수 있었다. 향후 본 연구에서 적용한 자동 주입관리 시스템을 이용하여 도출된 p-q-t chart를 활용한다면 주입재료, 주입공법, 주입속도 및 주입압 등 시공인자의 적합성을 판정하고 조정하는 객관적 지표로 활용하여 그라우팅 시공의 신뢰성을 획기적으로 향상시킬 수 있을 것으로 기대된다. The grouting is one of the improved techniques which is aim to decrease the permeability and to strengthen the soft ground. But The grouting method has many problems about a suitability of grouting procedure and an effectiveness of grouting after grouting work because of a technical characteristic operated inside the soil. The grouting $p{\sim}q{\sim}t$ chart of a typical index about grouting rate and time alteration of grouting pressure is one method to estimate the suitability of grouting factor with monitoring during grouting procedure. This study is automatic grouting system (AGS) which can control the testing and grouting procedures. It can make the detailed $p{\sim}q{\sim}t$ chart and analyze the grouting characters of the ground by comparing the detailed pattern of $p{\sim}q{\sim}t$ chart with standard pattern. If using the $p{\sim}q{\sim}t$ chart derived from AGS in the grouting work, it is an objective standard estimating the suitability of grouting factor with grouting materials, grouting method, grouting rate and grouting pressure, as results it expects successfully to improve reliability of the grouting work.

중,소하천에서 물리적 구조의 교란과 하안식생 귀화율의 관계

천예준 ( Yea Jun Chun ),최윤의 ( Yun Eui Choi ),홍선희 ( Sun Hee Hong ),전진형 ( Jin Hyung Chon ) 한국환경복원기술학회 2013 한국환경복원기술학회지 Vol.16 No.1

Current ecological stream restoration is focusing on recovery of physical characteristic and ecological functions of individual stream. For effective stream restoration, the relationship between stream environment and riparian flora should be investigated. The purpose of this study is to analyze the relationship between disturbance of hydromorphological structures and naturalized plants ratio in small to mid-sized streams. For the study sites, Gwanpyeong stream, Dongdal stream, and Yongchoo streams were chosen as reference stream` while, Gunnam stream, Anchang stream, and Hwa stream were chosen as damaged stream`. The hydromorphological structures of streams were evaluated with LAWA and flora of the streams were completely enumerated to calculate naturalized plants ratio. The result showed that there was a significant correlation between the outcome of LAWA and naturalized plants ratio(r=O.675, p<O.O 1). The result of factor analysis of LAWA identified three factors, River front and land use`, ``River bed materials and structures``, and ``Crossing structure and bar``. Among the factors of hydromorphological structures given by the result of factor analysis, ``river front and land use`` and ``bed materials and structures`` have statistically significant relationship with naturalized plants ratio(R20.470, p<O.O l). Given this results, quantitative analysis on the relationship between disturbance of hydromorphological structures of streams and naturalized plants ratio could provide some essential information for stream restoration. Also, as this study figured out major factors of hydromorphological structures that affect naturalized plants ratio, it might help monitor ecological states and current problems of small and mid-sized streams.

Prognostic Factors and Scoring Model for Survival in Metastatic Biliary Tract Cancer

Park, Hyung Soon,Park, Ji Soo,Chun, You Jin,Roh, Yun Ho,Moon, Jieun,Chon, Hong Jae,Choi, Hye Jin,Park, Joon Seong,Lee, Dong Ki,Lee, Se-Joon,Yoon, Dong Sup,Jeung, Hei-Cheul Korean Cancer Association 2017 Cancer Research and Treatment Vol.49 No.4

<P><B>Purpose</B></P><P> Metastatic biliary tract cancer (mBTC) has a dismal prognosis. In this study, an independent dataset of patients with mBTC was used to implement and validate a routine clinico-laboratory parameter-based scoring model for risk group identification.</P><P><B>Materials and Methods</B></P><P> From September 2006 to February 2015, 482 patients with mBTC were assigned randomly (ratio, 7:3) into investigational (n=340) and validation datasets (n=142). The continuous variables were dichotomized using a normal range or the best cutoff values determined using the Contal and O'Quigley statistical methods. Following a Cox’s proportional hazard model, the scoring model was derived by summing the rounded chi-square scores for the factors identified by multivariate analysis.</P><P><B>Results</B></P><P> The performance status (Eastern Cooperative Oncology Group 3-4), hypoalbuminemia (< 3.4 mg/dL), carcinoembryonic antigen (≥ 9 ng/mL), neutrophil-to-lymphocyte ratio (≥ 3.0), and carbohydrate antigen 19-9 (≥ 120 U/mL) were identified as independent prognosticators (Harrell’s C index, 0.682; integrated area under the curve, 0.653). Survival was clearly correlated with the risk groups (low, intermediate, and high, 14.0, 7.3, and 2.3 months, respectively; p < 0.001). The prognosis was also discriminative in the validation data set (median survival, 16.7, 7.5, and 1.9 months, respectively; p < 0.001). Chemotherapy did not offer any survival benefits for high-risk patients.</P><P><B>Conclusion</B></P><P> These proposed prognostic criteria for mBTC can facilitate accurate patient risk stratification and treatment-related decision-making.</P>

SOFC용 유리-세라믹섬유 복합기밀재의 고온 기체누설 거동

이재춘,권혁천,권영필,박성,장진식,이종호,김주선,이해원,Lee, Jae-Chun,Kwon, Hyuk-Chon,Kwon, Young-Pil,Park, Sung,Jang, Jin-Sik,Lee, Jongho,Kim, Joosun,Lee, Hae-Won 한국세라믹학회 2005 한국세라믹학회지 Vol.42 No.12

Glass composites containing ceramic fiber have been developed for Solid Oxide Fuel Cell (SOFC) seals. Effect of glass type, loading pressure and thermal cycle the leak rates of composite seals was investigated. Seal performance of two commercial glasses was compared with that of $SiO_2BaO-B_2O_3$ glass synthesized in this work. The leak rate for seals made of pyrex(R) increases from $\~0.0005\;to\;\~0.004sccm/cm$ as the gas pressure increases from 10 to 50 kPa. The soda lime silicate glass seal shows the leak rate two times higher than the one made of pyrex(R) or $SiO_2BaO-B_2O_3$ glass. The viscosity of glass at the seal test temperature is presumed to affect the leak rate of the glass seal. As the applied loading pressure increases from 0.4 to 0.8 MPa at $750^{\circ}C$, the leak rate decreases from 0.038 to 0.024 sccm/cm for composite seals. It has been found that during 50 thermal cycles between $450^{\circ}C\;to\;700^{\circ}C$ leak rates remained almost constant, ranging from 0.025 to 0.03sccm/cm. The results showed an excellent thermal cycle stability as well as sealability of the glass matrix ceramic fiber composite seals.

Poster Session:PS 1182 ; Cardiology : The Clinical Characterization and Preoperative Coronary Angiography of Cardiac Myxoma

( Tae Hyun Kim ),( Sang Hyun Lee ),( Yu Hee Choi ),( Soo Yong Lee ),( Jong Min Hwang ),( Min Ku Chon ),( Ki Won Hwang ),( Jeong Su Kim ),( Yong Hyun Park ),( June Hong Kim ),( Kook Jin Chun ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: The aim of our study was to investigate clinical features as well as coronary angiographic fi ndings in patients with cardiac myxoma. Methods: We performed a retrospective review of the 25 patients with cardiac myxoma, who had received surgical resection from July 2008 to June 2014 at our hospital, recording age, sex, symptoms, tumor location, echocardiography fi ndings and coronary angiography for each patient. Results: In 25 patients there were 9 (36%) men and 16 (64%) women with median age 55; range 17-69 years. The clinical features of 25 patients were showed in fi gure 1. fifteen (60%) patients underwent preoperative selective coronary angiography. All coronary angiographies showed that there were no signifi cant stenoses of coronary arteries. Thirteen (87%) cases of total 15 coronary angiographies showed ‘tumor vascularity’ looks like aterio-cavitary fi stula and feeding vessels. In the thirteen patients, eight (62%) patients had feeding arteries of myxoma from right coronary artery (RCA), three (23%) patients had feeding vessels from left circumfi ex coronary artery (LCx) and two (15%) patients had dual feeding arteries from RCA and LCx. There was no feeding artery from left anterior descending coronary artery (LAD). Conclusions: Our data demonstrated that the almost coronary angiograms (87%) to exclude concomitant coronary artery disease before surgery showed feeding vessels and tumor vascularity of cardiac myxoma from RCA or LCx. We showed that feeding arteries of cardiac myxoma from RCA were found more frequent than from LCx. Also, there was no feeding artery from LAD.

Poster Session : PS 0056 ; Cardiology : The Clinical Characterization and Preoperative Coronary Angiography of Cardiac Myxoma

( Taeh Yun Kim ),( Sang Hyun Lee ),( Yu Hee Choi ),( Soo Yong Lee ),( Jong Min Hwang ),( Min Ku Chon ),( Ki Won Hwang ),( Jeong Su Kim ),( Yong Hyun Park ),( June Hong Kim ),( Kook Jin Chun ) 대한내과학회 2014 대한내과학회 추계학술대회 Vol.2014 No.1

Background: The aim of our study was to investigate clinical features as well as coronary angiographic fi ndings in patients with cardiac myxoma. Methods: We performed a retrospective review of the 25 patients with cardiac myxoma, who had received surgical resection from July 2008 to June 2014 at our hospital, recording age, sex, symptoms, tumor location, echocardiography fi ndings and coronary angiography for each patient. Results: In 25 patients there were 9 (36%) men and 16 (64%) women with median age 55; range 17-69 years. The clinical features of 25 patients were showed in fi gure 1. Fifteen (60%) patients underwent preoperative selective coronary angiography. All coronary angiographies showed that there were no signifi cant stenoses of coronary arteries. Thirteen (87%) cases of total 15 coronary angiographies showed ‘tumor vascularity’ looks like aterio-cavitary fi stula and feeding vessels. In the thirteen patients, eight (62%) patients had feeding arteries of myxoma from right coronary artery (RCA), three (23%) patients had feeding vessels from left circumfl ex coronary artery (LCx) and two (15%) patients had dual feeding arteries from RCA and LCx. There was no feeding artery from left anterior descending coronary artery (LAD). Conclusions: Our data demonstrated that the almost coronary angiograms (87%) to exclude concomitant coronary artery disease before surgery showed feeding vessels and tumor vascularity of cardiac myxoma from RCA or LCx. We showed that feeding arteries of cardiac myxoma from RCA were found more frequent than from LCx. Also, there was no feeding artery from LAD.