기질성 뇌장애 환자의 구조적 뇌영상과 비교한 저해상 전자기 단층 촬영 영상

이승환,권구형,박영민,김 현,이강준,정영조 大韓神經精神醫學會 2006 신경정신의학 Vol.45 No.3

Objectives : Patients with organic brain lesion can produce unique slow waves (delta and theta) in the EEG. Basic assumption of this study was that the low resolution electro magnetic tomography (LORETA), an inverse source localization program, can provide functional images representing increased slow wave activity in these patients compared to normal subjects. Methods : The current study was performed by 18 channels digital EEG for 10 patients whose organic deficit have been Visually confirmed by CT or MRI. The source images of slow wave (1-7 Hz) frequency were produced by LORETA-key program. Results : We found that in eight out of ten subjects, LORETA successfully found out the source regions which were very closely matched to their original brain lesions. However in two subjects whose organic brain lesions were too small (<1cm) and located out of gray matter, we failed to find any increased slow wave activity compared with normal control. Conclusion : We can conclude that LORETA could be a useful method to provide functional imaging in patients with gray matter deficits in their brain. Its usefulness and limitations were discussed.

전경대원에서 발생한 결핵의 임상 양상

문창기,박상준,조민구,김영중,김소연,김윤권,정준오,안석진,김은실,서승오,김지훈,최원제,이윤영,박형기,최규영,김현근 대한감염학회 2006 감염과 화학요법 Vol.38 No.6

Background: The purpose of this study was to document the incidence and clinical characteristics of patients with tuberculosis (TB) in combat and auxiliary police, living in a group, in Korea where the incidence rate of active TB in a general population is higher than in Western countries. Materials and Methods:We retrospectively reviewed the medical records of all tuberculosis patients diagnosed at National Police Hospital from January 2002 through December 2004. Results:In 2002-2004, a total of 156 cases of tuberculosis were identified with the mean (Standard deviation) age of 20.6 (±1.0) years. Of these, 134 (85.9%) patients were registered as new cases, 11 (7.1%) as relapse, 2 (1.3%) as failure, 5 (3.1%) as treatment-after-default cases whereas 4 (2.6 %) patients were not included in any categories. Average annual new TB rate and smear-positive TB rate were 86.5/10^(5) and 17.4/10^(5) person-years, respectively. In 12 of 31 smear-positive cases, time from onset of symptoms to diagnosis was more than 30 days. Two multidrug-resistance TB cases were identified and two suspected outbreak episodes of TB had occurred during 3 years. Conclusion:There was no statistically significant difference in the incidence rate of new cases of TB between the general population aged 20 to 29 years and combat and auxiliary police in Korea. 배경 : 국내 결핵의 발생은 감소 추세에 있으나 여전히 후진국형 발생양상을 보이고 있다. 특히 집단생활을 하는 젊은이들에서 발생하는 결핵의 유행이 간헐적으로 알려지고 있어 우려를 낳고 있다. 이에 저자들은 최근 전경대원의 결핵 발병 양상에 대해 알아보고자 본 연구를 시행하였다. 재료 및 방법 : 2002년 1월부터 2004년 12월까지 3년간 경찰병원에서 결핵 진료를 받은 전경대원의 의무기록을 후향적으로 분석하여 연도별 결핵 신환발생률, 도말양성결핵 신환율, 진단 지연, 집단발병, 다제내성결핵을 조사하였다. 결과 : 연도별 결핵 신환자 수(10만명당 발생추정치)는 2002년 50명(83.6명), 2003년 42명(83.7명), 2004년 42명(93.5명)이었고 도말양성 폐결핵 신환자 수는 2002년 10명(16.7명), 2003년 11명(21.9명), 2004년 6명(13.4명)이었다. 3년간 도말양성 폐결핵 환자는 31명이 있었고 그 중 12명은 호흡기 증상 발생 30일이 지나서 진단을 받았다. 다제내성 결핵은 2명이 있었으며 결핵의 집단발병이 의심되는 사례는 2차례 있었다. 결론 : 전경대원과 20-29세 연령군 일반인의 결핵 신환발생률, 도말양성 폐결핵 발생률의 통계적으로 유의한 차이는 없었다.

숙련공에 의한 목탄제조과정 중 전통식 탄화로 내의 온도변화 (Ⅰ)

권구중(Gu-Joong Kwon),박형수(Hyung-Soo Park),이성재(Sung-Jae Lee),권성민(Sung-Min Kwon),이귀현(Gwi-Hyun Lee),김남훈(Nam-Hun Kim) 한국산림바이오에너지학회 2008 산림바이오에너지 Vol.27 No.1

숙련자에 의한 목탄제조과정 중 전통식 탄화로내의 온도변화와 목탄의 수율을 조사하였다. 온도 측정에는 플라티늄을 원료로한 R형의 열전지와 니켈을 원료로한 K형의 열전지를 이용하였다. R형의 온도측정범위는 0∼1600℃, K형은 0∼1200℃로 탄화로 내부는 R형을, 굴뚝부위는 K형을 사용하여 온도를 측정하였다. 탄화과정은 5일에서 6일 정도가 소요되었다. 탄재의 착화시 탄화로 내부의 온도는 약 700∼800℃였고 연통부위 온도는 약 80∼90℃였다. 목초액을 얻는 동안의 탄화로 내부온도는 약 600℃였고 굴뚝부위는 약 80∼90℃였다. 정련단계에 이르기까지 탄화로 내부온도는 증가하여 정련단계에서는 900∼1100℃의 고온에 달하였다. 정련단계에서 굴뚝의 온도도 크게 올라 약 600℃에 달하였다. 목탄의 수율은 9.8∼12.3%였다. 본 연구에서 전통식 탄화로를 이용한 숙련자의 목탄제조 과정 중의 온도변화 경과곡선과 목탄의 수율이 밝혀졌다. 얻어진 온도변화 경과곡선은 초심자의 제탄과정에서 지표의 하나로 이용될 수 있을 것이다. This study was performed to investigate the variation of temperature in a Korean traditional kiln controlled by an expert during carbonization process of wood. The yield of charcoal was also investigated. Two kinds of thermocouples, R-type and K-type, were used for measuring temperatures. Temperature tolerance of the R-type thermocouple prepared from platinum was from 0℃ to 1600oC and that of K-type thermocouple prepared from Nickel was from 0℃ to 1200℃. R-type was used for measuring temperature in the kiln while the K-type for measuring temperature in chimney. In this traditional kiln system, carbonization process was completed in five to six days. In the kiln, the ignition temperature was ranged from 700℃ to 800℃. During gathering wood vinegar, the temperature was kept around 600℃. And then the temperature were increased gradually prior to be refined. Finally, the temperature in refining process was reached to maximum point, 1000±10℃. In the chimney, the temperature was increased gradually from ca. 80℃ at ignition to ca. 600℃ at refining. The yield of wood charcoal was 9.8 to 12.3%. In this study, we showed the temperature profile through carbonization process in the traditional kiln and the yield of wood charcoal. The temperature profile can be used for beginner during carbonization process as a guideline.

Cloning and Expression of the Gene Encoding Glucose Permease of the Phosphotransferase System from Brevibacterium flavum in Escherichia coli

Kwon, Il,Lee, Kyu Nam,Lee, Jung Kee,Pan, Jae Gu,Oh, Tae Kwang,Lee, Hyung Hoan,Yoon, Ki Hong 한국미생물 · 생명공학회 1995 Journal of microbiology and biotechnology Vol.5 No.4

A Brevibacterium flavum gene coding for glucose permease of the phosphoenolpyruvate-dependent phosphotransferase system (PTS) was cloned by complementing the Escherichia coli ZSC113 mutations affecting a ptsG gene with the B. flavum genomic library. From the E. coli clone grown as red colony on a MacConkey plate supplemented with glucose as an additional carbon source, a recombinant plasmid was isolated and named pBFT93. The plasmid pBFT93 was identified as carrying a 3.6-kb fragment of B. flavum chromosomal DNA which enables the E. coli transformant to use glucose or mannose as a sole carbon source in an M9 minimal medium. The non-metabolizable sugar analogues, 2-deoxy-D-glucose (2-DG) and methyl-α-D-glucopyranoside (MeGlc) affected the growth of ZSC113 cells carrying the plasmid pBFT93 on minimal medium supplemented with non-PTS carbohydrate, glycerol, as a sole cabon source, while the analogues did not repress the growth of ZSC113 cells without pBFT93. It was also found that both 2-deoxyD-[U^-14C]glucose and methyl-αa-D-[U^-14C]glucopyranoside could be effectively transported into ZSC113 cells transformed with plasmid pBFT93. Several in vivo complementation studies suggested that the B. flavum DNA in pBFT93 encodes a glucose permease specific for glucose and mannose.

Time- and Dose-based Gene Expression Profiles Produced by a Bile-duct–damaging Chemical, 4,4′-methylene Dianiline, in Mouse Liver in an Acute Phase

Kwon, Sun-Bom,Park, Joon-Suk,Yi, Jung-Yeon,Hwang, Jae-Wong,Kim, Mingoo,Lee, Mi-Ock,Lee, Byung-Hoon,Kim, Hyung-Lae,Kim, Ju Han,Chung, Heekyoung,Kong, Gu,Kang, Kyung-Sun,Yoon, Byung-IL Sage Publications 2008 Toxicologic pathology Vol.36 No.5

<P>A toxicogenomics study was performed in the mouse liver after treatment of a bile-duct–damaging chemical, 4,4′-methylene dianiline (MDA), across multiple doses and sampling times in an acute phase using the AB Expression Array System. Imprinting control region (ICR) mice were given a single oral administration of a low (10 mg/kg b.w.) or high (100 mg/kg b.w.) dose of MDA. Mice were sacrificed six, twenty-four, and seventy-two hours after treatment for serum chemistry, histopathology, and mRNA preparation from liver samples. Treatment with MDA increased liver-toxicity–related enzymes in blood and induced bile-duct cell injury, followed by regeneration. To explore potential biomarker gene profiles, the altered genes were categorized into four expression patterns depending on dose and time. Numerous functionally defined and unclassified genes in each category were up- or down-regulated throughout the period from cellular injury to the recovery phase, verified by RT-PCR. Many genes associated with liver toxicity and diseases belonged to one of these categories. The chemokine-mediated Th1 pathway was implicated in the inflammatory process. The genes associated with oxidative stress, apoptosis, and cell-cycle regulation were also dynamically responsive to MDA treatment. The Wnt/β-catenin signaling pathway was likely responsible for the reconstitution process of the MDA-injured liver.</P>

In situ doping control and electrical transport investigation of single and arrayed CdS nanopillars

Gu, Leilei,Liu, Xi,Kwon, Kyungmook,La, Chih-Chung,Lee, Min Hyung,Yu, Kyoungsik,Chueh, Yu-Lun,Fan, Zhiyong The Royal Society of Chemistry 2013 Nanoscale Vol.5 No.16

<P>Highly aligned intrinsic and indium doped CdS nanopillar arrays were fabricated via a template assisted Solid Source Chemical Vapor Deposition method (SSCVD). The prepared nanopillar arrays were well aligned, dense and uniform in diameter and length. Their geometry can be well defined by the design of the templates. These unique properties make them promising candidates for future photonic and optoelectronic devices. The structure of the prepared nanopillars has been studied by high resolution transmission electron microscopy and their different growth orientation as compared to those grown in free space has been observed and interpreted by the template induced change of the liquid-solid interfacial energy and the surface tension at the edge of the circular interface. To investigate electrical property of CdS nanopillars, vertical nanopillar array devices and horizontal individual nanopillar field-effect transistors have been fabricated and characterized. The measurements showed that the location of the indium doping source significantly affected carrier concentration, conductivity and field-effect mobility of the prepared CdS nanopillars. Particularly, it was found that conductivity could be improved by 4 orders of magnitude and field-effect mobility could be enhanced up to 50 cm(2) V(-1) s(-1) via proper doping control. These results enable further applications of CdS nanopillars in nano-optoelectronic applications such as photodetection and photovoltaics in the future.</P>

Antitumor Activity of 23,24-dihydrocucurbitacin D IsoIated from Bryonia alba L.

Hyung Ok Sohn,Young Gu Lee,Heung Bin Lim,Nyoun Soo Kwon,Goorgen V. Aprikian,Dong Wook Lee 한국독성학회 2000 Toxicological Research Vol.16 No.4

Epidemiological Prevalence of Avian Pathogenic Escherichia coli Differentiated by Multiplex PCR from Commercial Chickens and Hatchery in Korea

Kwon, Soon-Gu,Cha, Se-Yeoun,Choi, Eun-Ju,Kim, Bo-Kyung,Song, Hee-Jong,Jang, Hyung-Kwan The Korean Society for Microbiology 2008 Journal of Bacteriology and Virology Vol.38 No.4

We examined 216 Escherichia coli (E. coli) isolated from chickens and environmental specimens from hatcheries between 2005 and 2006 in order to evaluate the epidemiological prevalence of avian pathogenic E. coli (APEC) in Korea tentatively by multiplex PCR. The multiplex PCR which was used as tentative criteria of APEC targets 8 virulence-associated genes; enteroaggregative toxin (astA), increased serum survival protein (iss), iron-repressible protein (irp2), P fimbriae (papC), aerobactin (iucD), temperature-sensitive hemagglutinin (tsh), vacuolating autotransporter toxin (vat), and colicin V plasmid operon (cva/cvi) genes. The number of detected genes could be used as a reliable index of their virulence. It was demonstrated that E. coli strains already typed as APEC always harbor 5 to 8 genes, but non-APEC strains harbor less than 4 genes. Assuming the criteria of APEC is a possession of more than 5 virulence-associated genes, we discriminated 24 APEC strains among the 216 E. coli strains. Contamination rates of APEC in the field were 31.3% in layers, 14.0% in broilers, 2.7% in broiler breeders, and 0.0% in environmental specimens from hatcheries. The combinational tendency of APEC examined is a fundamental possession of astA, iss and iucD genes and addition of cva/cvi, tsh, vat, and irp2 genes which have a critical importance for virulent traits of APEC. Compared with intravenous chicken challenge or embryo lethality assay, multiplex PCR method could be useful to discriminate APEC rapidly for convenient diagnosis.

CURRENT STATUS OF NUCLEAR FUSION ENERGY RESEARCH IN KOREA

MYEUN KWON,YOUNG SOON BAE,SEUNGYON CHO,최원호,홍봉근,황용석,JIN YONG KIM,KEEMAN KIM,YAUNG-SOO KIM,JONG-GU KWAK,HYEON GON LEE,SANGIL LEE1,나용수,BYUNG-HOON OH,YEONG-KOOK OH,박지연,HYUNG LYEOL YANG,IN KEUN YU 한국원자력학회 2009 Nuclear Engineering and Technology Vol.41 No.4

The history of nuclear fusion research in Korea is rather short compared to that of advanced countries. However, since the mid- 1990s, at which time the construction of KSTAR was about to commence, fusion research in Korea has been actively carried out in a wide range of areas, from basic plasma physics to fusion reactor design. The flourishing of fusion research partly owes to the fact that industrial technologies in Korea including those related to the nuclear field have been fully matured, with their quality being highly ranked in the world. Successive pivotal programs such as KSTAR and ITER have provided diverse opportunities to address new scientific and technological problems in fusion as well as to draw young researchers into related fields. The frame of the Korean nuclear fusion program is now changing from a small laboratory scale to a large national agenda. Coordinated strategies from different views and a holistic approach are necessary in order to achieve optimal efficiency and effectiveness. Upon this background, the present paper reflects upon the road taken to arrive at this point and looks ahead at the coming future in nuclear fusion research activities in Korea.

Performance Enhancement of Automatic Wood Classification of Korean Softwood by Ensembles of Convolutional Neural Networks

( Ohkyung Kwon ),( Hyung Gu Lee ),( Sang-Yun Yang ),( Hyunbin Kim ),( Se-Yeong Park ),( In-Gyu Choi ),( Hwanmyeong Yeo ) 한국목재공학회 2019 목재공학 Vol.47 No.3

In our previous study, the LeNet3 model successfully classified images from the transverse surfaces of five Korean softwood species (cedar, cypress, Korean pine, Korean red pine, and larch). However, a practical limitation exists in our system stemming from the nature of the training images obtained from the transverse plane of the wood species. In real-world applications, it is necessary to utilize images from the longitudinal surfaces of lumber. Thus, we improved our model by training it with images from the longitudinal and transverse surfaces of lumber. Because the longitudinal surface has complex but less distinguishable features than the transverse surface, the classification performance of the LeNet3 model decreases when we include images from the longitudinal surfaces of the five Korean softwood species. To remedy this situation, we adopt ensemble methods that can enhance the classification performance. Herein, we investigated the use of ensemble models from the LeNet and MiniVGGNet models to automatically classify the transverse and longitudinal surfaces of the five Korean softwoods. Experimentally, the best classification performance was achieved via an ensemble model comprising the LeNet2, LeNet3, and MiniVGGNet4 models trained using input images of 128 × 128 × 3 pixels via the averaging method. The ensemble model showed an F1 score greater than 0.98. The classification performance for the longitudinal surfaces of Korean pine and Korean red pine was significantly improved by the ensemble model compared to individual convolutional neural network models such as LeNet3.