캔음료중 epichlorohydrin 의분석법에 관한 연구

이광호,곽인신,최재천,전대훈,김형일,강경모,최병희,김귀정,이철원 식품의약품안전청 2001 식품의약품안전청 연보 Vol.5 No.-

캔식품중에 잔류하는 epichlorohydrin을 분석하기 위한 pu링e & trap-Cc/uf통D 분석법을 확립하여 캔의 lacauer 코팅제에서 식품으로 이행되어 잔류하는 epichtorohydfn을 측정하고, 식품유사용매에 의한 용출시험을 통해 일일추정섭취량을 산출하였다. epichlorohydrin의 검량선은 y=0.0006x+0.OO6?(R큰0.9983)의 직선성·라 0.05#ga의 검출한계를 나타내었다. 각종 음료 및 식품유사용매에 일정량의 epichlorohydrin을 첨가한 후 분석하였을 때 회수을은 72~91%였으며, 실제 시판되는 f5건의 캔음료 중 잔류하는 epichlorohydrin을 측정한 결과 모든 캔음료에서 검출한계(0.1#94) 이하였다. 제관업체에서 구입한 modifed epoxy, epoxy phenolic, vinyl organosol, epoxy phenol ester 등의 BADGE(bisphenol A diglycidyt ether)형 에폭시수지로 lacquer 코팅된 식품용 캔에 식품윤사용매인 10% 또는 95% 에탄올을 층L진한 후 90~121'c의 드라이오븐에서 30분~2시간동안 용출시켰을 패 캔의 lacquer 코팅재에서 식품유사용매로 이행되는 epichBorollydirn은 코팅재질, 그리고 가열온도 및 시간에 문관하게 모든 캔에서 검출한계(0.4#ga)이하 였다. 위의 용출결과를 FD.f_의 "Recommendation for Chemistry Data for Indirect Food Additive Petition" 윽 일일추정섭취량 산출법에 적용하여 얻은 epichtorohydrin의 일딜추정 섭 취 량은 0.2r조persorday이하였다. A sensitive ana1?~7tical method based on gas cl)romatogFapy~mass spectrometry with a selected ion monitoring (GE/hfS-Slhf) and the purge-and-trap concentrator ))·asdeveloped for determining ot'epicillorohydrin in canr;ed be)#erages coated with eporl· resin. Thecalibration rurve in the ranre of 0.j ~50nr had'correlation coefficient of 0.9983 and detection limit of 0.Osrga. Recoveries of epichlorohydrin spiked to beverages were in the range of 72 ~91% with detection limits of 0.1 #ga. fn survey of epichlorohydff in twenty commercialcanned beverage samples, epichlorohydrin was not found in all the samples with the detectionlimit of 0.1 r9a. In migration test of various cans coated with BADGE-based coating cans;modifed epoxy, epoxy phenolic, vinyl organosol, epox?· phenol ester were exposed to the foodsimulants of 10% ethanol and 95% ethanol. flfo delectable epichlorohydrin migrated to foodsiHulants was found in aTl the cars with detection Jimit of 0.4 #9/L. Using the miEration data,along uTith the applicstion of food and beverage cans complied with FDA's "Recommendationfor Chemlstry Data f,3r Indirect Food Additive Petition" , the potential dietary exposure toepichlorohydrin was estlmated to be under 0.2rf/person/day.

성장호르몬 결핍증과 특발성 저신장증 환아에서 성장호르몬의 치료 효과

강정철,최윤석,최인경,김호성,김덕희 대한소아과학회 2004 小兒科 Vol.47 No.3

식이를 통한 농약섭취량에 관한 연구 : 두류, 서류, 견과류, 종실류, 채소류, 과실류 및 그 가공품에 대하여 legumes,potatoes,nuts,seeds,vegetables,fruits and their products

원경풍,홍무기,최동미,오창환,박건상,최윤주,안장혁,황인균,정지윤,정선미,박일경,이정복,장선영,홍주연,최영내 식품의약품안전청 1998 식품의약품안전청 연보 Vol.2 No.-

우리가 섭취하는 식품을 수세 , 탈피, 가열 등으로 섭취직전의 상태로 조리하여 잔류농약을 분석하였다. 그 결과 식품 섭처를 통한 농약의 1일 춘정 섭취량(EDI : estimated daily intake)을 파악하고 이를 농약의 1일섭취허용량(ADI : acceptabte daily intake) 및 이론적 최대섭취량(TffDt : theoretical maxiraum daily in늘he)과 비교하여 우리나라 국민이 식품으로부터 섭취하는 농약의 양에 대한 안전성을 평71하였다. 보편성있는 식품수거를 위채 수거대상 지역은 인구가 밀집되어 있는 대도시인 서울, 부산, 대구』 인천 , 대전, 광주, 수원, 전주, 마산과 춘천의 10곳을 선정하였다. 대상식품으로는 두류 및 가공품 11종, 서류 및 가공품 3종.견과류 및 가공품 8종, 기호식물류 1종, 종실류 2총, 과실류 및 가공품 20종, 채소류 21종의 총 50종of었다. 분석대상농약은 동시다셩분 분석채 가능한 농약으로 HPD대상농약 11종 및 ECD대상농약 48종으로 총 59졸이었다. 1995년부터 5개년 계획으로 수행되어 온 본 딴구는 큼년이 4차년도였으며,종전보다 대상식품 및 대상농약을 크게 늘리고 시료 전처리에 있어석 자동화된 고상추출 정제법을 사용하여 시료 처리속도를 창상시켰다. 분쇄된 시료들은 acetonitrile로 추출한 후 정제하여 GC/BCD 및 GC/HPD로 분석하고 검출된 성분들은 GC/MSD로 재확인차였다. 분석 결과 총 660 식품중 9식품(딸기, 복숭아, 풋고추, 고춧가루, 파, 피망, 상추, 시금치 , 깻잎 )에서 4종의 농약(procymidone, EPN, endosulfan, chlorpyrifos)이 검출피었으며, 이들 식품 십취를 통한 농약의 추정 섭취량()801)은 0.01 ~ 1.28rg/person/day 수준으로 극히 미팡이었다. 대상농약중에서 가장 많이 섭취되고 있는 농약은 on(losulfan으로 그 EDI를 ADI와 ㅂ1교한 결과 0.39%에 불과 하였으며, 이론적 최대섭취량(TMDI)과 비교한 결과도 0.49% 수준으로 나타났다. 따라서 본 연구의 대상식품을 섭치할 경우 분석대상 농약으로 인한 안전성에는 문제가 얼는 것으로 려가되었다. In order to rstimate the intake of pesticide residues through foods which is prepared ready to eat, total diet study(TDS) was carried. The foods(legumes, potatees, nuts, seeds, fruits, vegeta-bles a8d their products) were purchased at the retail stores in 10 large cities of Korea, respectively. Thecollected 660 samples(66 foods x10 regions) were pr,etreated in a manBer similar to that used at home(washing, trimming, peeling. boiling and etc ) and followed Uy the automated solid phase extraction.Frem the extracted samples, total 59 pesticides were determined by capillary gas chromatography withECD, NPD and MSD. The levels of pesticide residues were resulted in not detected or orders of magni-tude lower than maximum residve limits for most of samples. However, in 9 samples(strawberrf, peach,green pepper, red pepper powder, scallion, bell pepper, lettuce korean, spinach, wild sesame leaf),4 pesti-cides(procymidone, chlorpyrifos, endosulfan, EPN) were detected with the estimated daily intake(EDE)values of fftl ~l.28rg/person/day. These EBI values were corresponded to <0.01 ~ 1.82% of ADT(for55kg person) and <0.01 ~O.49% of TMDI.

공간정보에 기반한 도로 데이터 자동생성 방법

주인학,최경호,유재준,황태현,이종훈,Joo, In-Hak,Choi, Kyoung-Ho,Yoo, Jae-Jun,Hwang, Tae-Hyun,Lee, Jong-Hun 한국공간정보학회 2002 개방형지리정보시스템학회 논문지 = Journal of the Korea Open Geogr Vol.4 No.2

효율적인 도로정보의 구축은 GIS에서 가장 중요한 주제이다. 본 논문에서는 도로정보를 자동으로 생성, 구축하기 위하여 모바일 매핑 기술과 영상인식 기술을 결합한 방법을 제안하였다. 모바일 매핑 시스템은 CCD 카메라, GPS, INS를 장착한 차량의 형태를 가지며, 취득한 영상에 나타난 공간객체의 좌표를 사진측량기법을 이용하여 계산한다. 모바일 매핑 시스템에 의한 공간객체 좌표추출과 데이터 구축은 자동화되지 않아 시간이 많이 드는 단점이 있다. 도로의 자동 인식은 영상인식 분야에서도 자동주행차량에 대한 연구의 형태로 진행되어 왔다. 그러나 영상인식에 기반한 방법들은 도로 차선에 적용할 경우 차선의 끊김 차량에 의한 가려짐 좋지 않은 날씨와 조명 등 실제의 도로나 도로변의 다양한 예외상황 때문에 원하는 결과를 얻기 힘든 경우가 많다. 이러한 단점을 보완하기 위하여 본 논문에서는 모바일 매핑 시스템으로부터 획득된 GPS/INS 데이터 및 영상인식 기술을 모두 이용한 자동 도로데이터 생성방법을 제안하였다. 영상에 나타난 도로 차선의 3차원좌표로부터 영상에서 객체가 나타날 위치를 추정하기 위한 방법을 고안하였으며, 이러한 방법은 도로 차선을 찾기 위한 복잡한 영상처리 과정을 대폭 줄일 수 있다. 예외상황 때문에 도로차선을 추출하지 못한 경우에는 스플라인 인터폴레이션에 의하여 값을 얻는다. 인터폴레이션은 교차로나 급격한 변화 지점에 따라 구분된 도로 구간 단위로 이루어진다. 본 논문에서는 제안된 객체좌표 추정방법과 인터폴레이션 기법에 대한 실험 및 결과를 제시하였다. VEfficient generation of road data is one of the most important issues in GIS (Geographic Information System). In this paper, we propose a hybrid approach for automatic generation of road data by combining mobile mapping and image processing techniques. Mobile mapping systems have a form of vehicle equipped with CCD camera, GPS, and INS. They can calculate absolute position of objects that appear in acquired image by photogrammetry, but it is labor-intensive and time-consuming. Automatic road detection methods have been studied also by image processing technology. However, the methods are likely to fail because of obstacles and exceptive conditions in the real world. To overcome the problems, we suggest a hybrid method for automatic road generation, by exploiting both GPS/INS data acquired by mobile mapping system and image processing algorithms. We design an estimator to estimate 3-D coordinates of road line and corresponding location in an image. The estimation process reduces complicated image processing operations that find road line. The missing coordinates of road line due to failure of estimation are obtained by cubic spline interpolation. The interpolation is done piecewise, separated by rapid change such as road intersection. We present experimental results of the suggested estimation and interpolation methods with image sequences acquired by mobile mapping system, and show that the methods are effective in generation of road data.

Transfer of ultrathin molybdenum disulfide and transparent nanomesh electrode onto silicon for efficient heterojunction solar cells

Kang, Sung Bun,Kwon, Ki Chang,Choi, Kyoung Soon,Lee, Rochelle,Hong, Kootak,Suh, Jun Min,Im, Min Ji,Sanger, Amit,Choi, In Young,Kim, Soo Young,Shin, Jae Cheol,Jang, Ho Won,Choi, Kyoung Jin Elsevier 2018 Nano energy Vol.50 No.-

<P><B>Abstract</B></P> <P>Two-dimensional transition-metal dichalcogenides (TMDCs) are very promising for photovoltaic (PV) applications due to their excellent light absorption properties and appropriate bandgap energy, Although multifunctional applications of TMDCs in photovoltaic devices have been achieved, the photovoltaic conversion efficiency under 1 sun is still very low with small active area because of their inexpedient high sheet resistance and limitation of synthesis techniques. In this study, we demonstrate uniform synthesis of 4-in. wafer-scale MoS<SUB>2</SUB> thin films by thermal decomposition of solution precursors. The solar cells are fabricated by transferring n-MoS<SUB>2</SUB> thin films on p-Si substrates to form p-n heterojunctions and then transferring Au nanomeshes prepared in a novel surface treatment as transparent top electrodes onto MoS<SUB>2</SUB>. The circular n-MoS<SUB>2</SUB>/p-Si heterojunction solar cell exhibited a power conversion efficiency of 5.96% at a diameter of 0.3 in. and proved to be easily scalable to 1-in. diameter with 5.18% efficiency. To the best of our knowledge, the solar cells of this study are the most efficient and the largest in all types of solar cells based on TMDC reported so far. Finally, based on finite difference time-domain simulation, we proposed a strategy for implementing n-MoS<SUB>2</SUB>/p-Si heterojunction solar cell with efficiency higher than 15% by introducing optimal doping control of n-MoS<SUB>2</SUB> and efficient anti-reflection layers.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The large scale, uniform (4-in.) MoS<SUB>2</SUB> thin films are synthesized. </LI> <LI> High transparent, low sheet resistances electrodes are fabricated in a novel way. </LI> <LI> The efficient MoS<SUB>2</SUB> based solar cells are developed by all transfer process including top electrodes. </LI> <LI> The highest, largest MoS<SUB>2</SUB> p-Si/ heterojunction solar cells are demonstrated. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P> <B>The highest performance (5.96%), largest area (1 in.) n-MoS2/p-Si solar cells with transparent electrodes fabricated by a novel way.</B> The transparent electrodes lowers the series resistance of the fabricated solar cells, facilitating the collection of photo-generated carriers from the junction. In our knowledge, we have achieved the highest photovoltaic performance at largest active area by using transparent nanomesh electrode among TMDC based solar cells.</P> <P>[DISPLAY OMISSION]</P>

Natural products used as a chemical library for protein–protein interaction targeted drug discovery

Jin, Xuemei,Lee, Kyungro,Kim, Nam Hee,Kim, Hyun Sil,Yook, Jong In,Choi, Jiwon,No, Kyoung Tai Elsevier 2018 Journal of molecular graphics & modelling Vol.79 No.-

<P><B>Abstract</B></P> <P>Protein–protein interactions (PPIs), which are essential for cellular processes, have been recognized as attractive therapeutic targets. Therefore, the construction of a PPI-focused chemical library is an inevitable necessity for future drug discovery. Natural products have been used as traditional medicines to treat human diseases for millennia; in addition, their molecular scaffolds have been used in diverse approved drugs and drug candidates. The recent discovery of the ability of natural products to inhibit PPIs led us to use natural products as a chemical library for PPI-targeted drug discovery. In this study, we collected natural products (NPDB) from non-commercial and in-house databases to analyze their similarities to small-molecule PPI inhibitors (iPPIs) and FDA-approved drugs by using eight molecular descriptors. Then, we evaluated the distribution of NPDB and iPPIs in the chemical space, represented by the molecular fingerprint and molecular scaffolds, to identify the promising scaffolds, which could interfere with PPIs. To investigate the ability of natural products to inhibit PPI targets, molecular docking was used. Then, we predicted a set of high-potency natural products by using the iPPI-likeness score based on a docking score-weighted model. These selected natural products showed high binding affinities to the PPI target, namely XIAP, which were validated in an <I>in vitro</I> experiment. In addition, the natural products with novel scaffolds might provide a promising starting point for further medicinal chemistry developments. Overall, our study shows the potency of natural products in targeting PPIs, which might help in the design of a PPI-focused chemical library for future drug discovery.</P> <P><B>Highlights</B></P> <P> <UL> <LI> This paper provides <I>in silico</I> drug discovery strategy to identify natural products capable to inhibit the protein–protein interactions. </LI> <LI> The predicted PPI inhibitor-like natural products were validated in an in vitro experiment. </LI> <LI> The XIAP inhibitor LENP0044 could be used as a potent template for further chemical optimization. </LI> <LI> Natural products can be used as potent candidates in the design of a PPI-focused chemical library for drug discovery. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

돼지 난포란의 동결보존

최인경,송해범 대구대학교 생명과학연구소 2004 생명과학연구 Vol.3 No.1

Abstract : The cryopreservation of embryos has become a powerful tool in assisted reproduction in several mammalian species. Embryos are cryopreserved by slow freezing or by vitrification. However, consistently high survival has not been obtained in most oocytes and in some embryos. The main reasons for the low survival would be sensitivity to low temperatures, which leads to chilling injury, and low permeability of the cell membrane, which leads to the formation of intracellular ice. As a strategy aiming to overcome these injuries, modified vitrification methods have been devised in which the cooling and warming rate is markedly incresed by minimizing the column of the solution and the container. Furthermore, porcine oocytes and embryos are influenced just by chilling to below 15℃.

Flubendazole의 편충에 대한 구충효과

최원영,남호우,유채을,한인수,한경용 최신의학사 1988 最新醫學 Vol.31 No.7

분광색채계측기를 이용한 Vita Shade 광중합형 복합레진의 색상 비교

조경이,황인남,최홍란,오원만 大韓齒科保存學會 1998 Restorative Dentistry & Endodontics Vol.23 No.1

To get a satisfactory result in the composite resin restorations, it is necessary to choose correct shade. At present, most of the commercial composite resins are based on the Vita Lumin shade guide or Bioform shade guide. but color differences might be expected even using the same shade in various materials. In this study, five kinds of light cured composite resins with A2 and B3 shade were used to measure and compare the color each other while one porcelain served as a control. All composite resins (Spectrum TPH (SP), VeridonFil-Photo (VE), Z100 (Z100), Charisma (CH), Prodigy (PRO)) were filled in to the metal mold (12 mm diameter, 2 mm depth), followed by compression, polymerization and polishing with wet sandpaper. The specimens of porcelain were fabricated by using the refractory mold for porcelain. After 24 hours, the specimens were placed on the spectrocolorimeter and spectral reflectance were measured under CIE illuminant D65. After measuring the values of L*, a*, b* and ΔE*, following results were obtained; 1, The L*, a* and b* values of both shade of porcelain specimens showed significantly higher than those of resin specimens(p<0.05). 2. In comparing the resin specimens of the A2 shade, differences were significant except L* values of SP-CH and PRO-VE, a* values of the VE-SP and b* values of the VE-Z100 and SP-PRO(p<0.05). 3. In comparing the resin specimens of the B3 shade, differences were significant except L* values of PRO-SP(p<0.05). 4. In comparing the resin specimens of the A2 shade, color differences between materials(ΔE*) showed the lowest value of 1.66. and the highest was 5.16. ΔE* values of the materials of VE-PRO, CH-PRO, SP-PRO, SP-Z100 and SP-CH were lower than 3.3. 5. In com0paring the resin specimens of the B3 shade, the lowest value of the ΔE* was 0.57 and the highest was 5.92. ΔE* values of Z100-CH and SP-PRO were lower than 3.3. The present study revealed there was perceptible color difference between materials even if they have the same designated shade based on Vita shade guide. The results of the present study suggested that it would be necessary to establish the reproducible and constant color specification system for an esthetic restoration.

노인에서 정서 인식의 저하

이경욱,채정호,최인철,이해국,권용실,이정태 大韓神經精神醫學會 2005 신경정신의학 Vol.44 No.2

Objectives : The purpose of this study was to investigate whether elderly and young adults differ in their recognition of facial expressions of emotion. Methods : A total of 120 (elderly group 53, young group 67) subjects participated in this study. Korean facial expressions of emotion including happiness, sadness, fear, anger, disgust, surprise and neutral were used as stimuli for facial affect recognition test. Computerized facial affect recognition test that consists of facial affect discrimination test and facial affect intensity test was performed. Results : For facial affect discrimination test, there was a significant difference between two groups (F==3.986, P<.01) after controlling the effect of education. Elderly participants showed significantly less correct recognition rate with sadness, anger and disgust (p<.05). For facial affect intensity test, there was no significant difference between the groups in recognition of emotional intensity. Chi-square test or t-test was done according to the clinical variables. Multivariate analysis of covahance was done to test group differences of correct recognition rate and emotional intensity. Conclusion : This is the first report of differential decrease of facial affect recognition in elderly using Korean facial expressions. This study suggests that the decrement of facial affect recognition maye be a part of normal aging process.