연구 논문 : 전기화학적 마이크로머시닝 기술을 이용한 균일한 니오븀 표면 에칭 연구

김경민 ( Kyung Min Kim ),유현석 ( Hyeon Seok Yoo ),박지영 ( Ji Young Park ),신소운 ( So Woon Shin ),최진섭 ( Jin Sub Choi ) 한국공업화학회 2014 공업화학 Vol.25 No.1

본 연구에서는 micro-contact printing을 통하여 니오븀 호일 표면 위에 균일한 에칭 pits를 형성하였다. 균일한 보호층을 형성하고자 전해연마의 효과를 확인하였으며, 기존의 O2 플라즈마 공정 없이 손쉽게 균일한 에칭 pits를 형성시킬 수 있는 조건을 확인하였다. 메탄올 혼합 전해질을 사용하여 10 min 동안 에칭을 진행한 결과 니오븀 호일 표면 위에 지름과 간격이 각각 10 μm와 5 μm로 잘 정렬된 에칭 pits를 관찰하였다. We describe the preparation of highly-ordered etching pits on the Nb foil through a micromachining. The effects of electro-chemical polishing on the formation of uniformly-patterned protective epoxy layer was investigated. Unlike the previous proc-ess using O2 plasma, well-ordered etched pits were prepared without any dry processes. As a result, the Nb foil with the well-ordered pits of 10 μm × 5 μm could be obtained by electrochemical etching in methanolic electrolytes for 10 min.

저사이클 피로수명에 영향을 미치는 구상흑연주철의 흑연입자수의 영향

김민건,이병현,유병호 강원대학교 산업기술연구소 2000 産業技術硏究 Vol.20 No.B

Low cycle fatigue life of spheroidal graphite cast iron is determined by the morphological parameters of internal graphite. The aim of this study is to clarify the effect of the number of nodular grain of spheroidal graphite cast iron on low cycle fatigue life. Two specimens that have identical average nodular grain size by changing nodular grain volume fraction and different number of nodular grain count was tested. In this paper, the parameter governing fatigue life through fatigue test, the number of nodular grain seriously affect fatigue life and nodular grain size is no longer governing parameter of it.

위성 ATM 망에서 ABR 서비스를 위한 트래픽 전송방식에 관한 연구

최병석,박재현,박현민,안현석,유재욱 동국대학교 산업기술연구원 1997 산업기술논문집 Vol.9 No.-

ATM의 ABR 서비스는 기본적으로 전달지연이 작은 지상망에 적합하게 개발되었기 때문에 위성 망과 같이 전달지연이 큰 상황에서는 망의 심각한 폭주나 링크의 채널 전송률 저하 등이 발생될 수 있다. 또한 위성채널은 지상 ATM 망에 비해 대역이 제한되어 있으므로 폭주를 미연에 방지하기 위해 보다 치밀하고, 지연에 덜 민감한 대역할당 알고리즘이 필요하다. 본 논문에서는 EPRCA 기반의 위성탑재 ATM 교환기로 구성된 위성 ATM 망에서 BECN과 큐의 상태정보를 이용하여 위성 ATM 망에서 ABR 서비스를 제공할 수 있는 방안을 제안하였다.

당뇨병과 동반된 화농성 간농양의 임상상 및 예후인자

오은숙,강무일,이원영,오기원,임동준,이소영,이정민,고승현,김성래,안유배,손현식,윤건호,차봉연,이광우,손호영,강성구 대한당뇨병학회 2000 임상당뇨병 Vol.1 No.1

연구배경: 감염질환은 혈관질환과 함께 당뇨병의 중요한 사망원인의 하나이며, 혈당조절이 불량할수록 감염 빈도가 증가됨은 잘 알려져 있다. 간농양의 발생이 있어서도 당뇨병은 중요한 기저질환 중의 하나이다. 일반적으로 간농양의 가장 흔한 원인균은 Escherichi coli라고 알려져 있으나, 최근 당뇨병을 가진 간농양 환자에서 Klesiella pneumoniae의 검출이 증가되고 있다. 또 최근 연구에 의하면 K.pneumonie가 간농양의 가장 흔한 원인균이며, K. pneumoniae에 의한 간농양은 K.pneumoniae 이외의 균주에 의한 간농양보다 당뇨병과 밀접히 관련되어 있다고 보고된 바 있다. 이에 저자들은 간농양 환자를 대상으로 당뇨병환자의 빈도를 알아보고, 그 원인균 및 특징을 비당뇨병 환자들의 경우와 비교해 보고자 하였다. 방법: 1992년 1월부터 1999년 6월까지 방사선학적 검사 혹은 수술에 의해 간농양이 확인되거나, 경피적 천자나 수술을 통한 배농액 배양, 혹은 혈액 검사에서 원인균이 증명된 182명의 환자를 대상으로 후향적 임상고찰을 실시하였다. 결과: 화농성 농양을 가진 167명의 환자(남:94명, 여:73명)중 당뇨병을 가진 환자는 54명 (남:30명, 여:24명)으로 32.3%를 차지하였다. 환자의 평균나이는 당뇨군에서 62.1 ± 13.4세, 비당뇨군에서는 55.1 ±15.5세로 당뇨군에서 높았으며(p=0.0021), 남녀간의 평균나이 비교 시 두 군 모두 여성의 나이가 의미있게 높았다. 비당뇨군에 비하여 당뇨군의 경우 저알부민혈증의 빈도와 aspartate transaminase가 증가되어있었다. 원인균주는 K. pneumoniae (당뇨군54%, 비당뇨군 39.1%), E. coli(당뇨군 17.5%, 비당뇨군 18.8%), Pseudomonas aeruginosa, Streptococcus viridans, Enterococcus 순이었으며 두 군간의 의미는 차이는 없었으나 K. pneumoniae의 경우 다른 균종에 비해 단독감염의 빈도가 높았다(82.8%). 사망률은 당뇨군에서 16.7%, 비당뇨군에서 7.1%로 당뇨군에서 의미있게 높았으며(p=0.019), 당뇨군에서의 사망환자는 모두 패혈증이 동반되어 있었다. 당뇨환자의 사망군은 생존군에 비해 당뇨병 이환기간이 길고 혼합감염의 빈도가 높았다(p=0.046). 검사실 소견에서는 총 빌리루빈 및 알카리성 포스파타제의 증가가 관찰되어 있었다. 결론: E. coli가 간농양의 주된 원인균이라는 기존 보고와는 달리 당뇨군과 비당뇨군 모두 K. pneumoniae가 간농양의 주된 원인균이었다. 또한 당뇨 유병기간이 길고 당뇨조절이 불량한 환자에서 혼합감염이며 총 빌리루빈 및 알카리성 포스파타제의 증가등과 같은 위험인자가 존재할 경우 사망률이 증가될 수 있으므로 이들 군에서는 적극적인 치료가 필요할 것으로 사료된다. Background: Liver abscesses are commonly associated with underlying disease, particularly diabete mellitus. The number of the liver abscesses caused by Klebslella pneumoniae in diabetic patient has been increased in Korea nowadays. This study was conducted to clarify the clinical presentation and prognostic factors of pyogenic liver abscesses, especially in diabetic patients and to determine the proportion of K. pneunomiae as a pathogen in liver abscess in Korea. Methods: Medical records of 167 patients treated for pyogenic liver abscess from January, 1992 through June, 1999 were reviewed retrospectively in detail. Major Pathogenic organism, clinical manifestations, prognostic factors, the importance of diabetes mellilus as an underlying disease and its effect on clinical features and prognosis were analyzed. Results: Among 167 cases of pyogenic liver abscess, underlying diabetes mellitus was present in 32.3%. The mean age of patients was 62.7 13.4 years in diabetic liver abscess group and 55.1 15.5 years in non-diabetic liver abscess group. Most liver abscesses were cryptogenic in origin or secondary to the billary tree diseases. The clinical presentations among the two groups were not significantly different. When compared to patients without diabetes, patients with diabetes had significantly higher proportions of hypoalbuminemia and elevated aspartate transaminase level. The most common organism of the pyogenic abscess was K. pneumoniae in both groups. Percutaneous drainage of the abscess with appropriate antibiotics was the most commonly used therapeutic modality in liver abscess. The mortality rate of diabetic liver abscess is 16.1 % and 7.1% in nondiabetic liver abscess. Complications, especially septicemla, were found more frequently in patients with diabetes than in patients without diabetes (64.8% vs 28.3%, septicemia : 31.5% vs 9.7%). The factors influencing mortality in the diabetic liver abscess were disease duration, mixed infection, presence of septicemia, elevated bilirubin and alkaline phosphatase. Conclusions: In contrast to prior report that the E. coli was the most common pathogen in liver abscess, we found that K. pneumoniae was the most common organism cultured in liver abscess. Diabetic patients have more complications and higher mortality than patients without diabetes. Early detection and proper treatment are needed to improve the outcome for diabetic patient with liver abscess.

Feasibility study for the assessment of the exposed dose with TENORM added in consumer products

Yoo, Do Hyeon,Lee, Hyun Cheol,Shin, Wook-Geun,Ha, Wi-Ho,Yoo, Jae Ryong,Yoon, Seok-Won,Lee, Jiyon,Choi, Won-Chul,Min, Chul Hee Oxford University Press 2015 Radiation protection dosimetry Vol.167 No.1

<P>Consumer products including naturally occurring radioactive material have been distributed widely in human life. The potential hazard of the excessively added technically enhanced naturally occurring radioactive material (TENORM) in consumer products should be assessed. The aim of this study is to evaluate the organ equivalent dose and the annual effective dose with the usage of the TENORM added in paints. The activities of gammas emitted from natural radionuclides in the five types of paints were measured with the high-purity germanium detector, and the annual effective dose was assessed with the computational human phantom and the Monte Carlo method. The results show that uranium and thorium series were mainly measured over the five paints. Based on the exposure scenario of the paints in the room, the highest effective dose was evaluated as <1 mSv y<SUP>−1</SUP> of the public dose limit.</P>

Average thickness of internal anal sphincter on transrectal ultrasonography in Korean adult population

Hyeon-Min CHO,Bong-Hyeon KYE,Ri Na YOO,HyungJin KIM 대한외과학회 2017 대한외과학회 학술대회 초록집 Vol.2017 No.11

Transcriptional Regulator CTR9 Inhibits Th17 Differentiation via Repression of IL-17 Expression

Yoo, Hyeon-Seok,Choi, Yongwook,Ahn, Narae,Lee, Saseong,Kim, Wan-Uk,Jang, Min Seong,Jang, Myoung Ho,Kim, Yon Su,Yoo, Joo-Yeon The American Association of Immunologists, Inc. 2014 JOURNAL OF IMMUNOLOGY Vol.192 No.4

<P>PAF complex is an evolutionarily conserved transcriptional complex that associates with RNA polymerase II in the coding region of actively transcribing genes. Although its transcriptional activity is closely related to diverse cellular processes, such as cell-cycle progression or development in mammals, its role in immune responses has not been addressed yet. In this study, we show that CTR9, a component of PAF complex, functions as a repressor of Th17 differentiation. Both mRNA and protein levels of CTR9 were significantly decreased during the differentiation processes of naive T into Th17 effector cells. When CTR9 was depleted, IL-17 expression was induced and differentiation into Th17 cells enhanced. In naive T cells, CTR9 occupied the coding region of <I>Il17a</I>, but dissociated under Th17 in vitro-polarizing conditions. In contrast, both CDC73 and PAF1 were recruited to the <I>Il17a</I> locus under Th17-differentiation conditions. In the IL-6–stimulated splenocytes, expression of CTR9 was decreased, and chromatin-bound CTR9 disappeared in the coding region of <I>Il17a</I>. IL-6 also directly repressed expression of CTR9 gene, as promoter activity of CTR9 was similarly repressed by IL-6 treatment. Moreover, in mice with collagen-induced arthritis, lentivirus-mediated CTR9 overexpression in the joints ameliorated arthritis severity, decreasing the frequency of CD4<SUP>+</SUP>IL-17<SUP>+</SUP> T cells in lymph nodes. In conclusion, our data propose a novel feed-forward loop of IL-17 transcriptional regulatory circuit, via IL-6–mediated repression of CTR9 which is a transcriptional repressor of IL-17.</P>

User Association and Load Balancing based on Monte Carlo Tree Search

Hyeon-Min Yoo,Jung-Mo Moon,Jee-Hyeon Na,Een-Kee Hong 한국통신학회 2023 한국통신학회 학술대회논문집 Vol.2023 No.2

Mutational analysis of caspase genes in prostate carcinomas

KIM, MIN SUNG,PARK, SANG WOOK,KIM, YOO RI,LEE, JI YOUL,LIM, HYEON WOO,SONG, SANG YONG,YOO, NAM JIN,LEE, SUG HYUNG Blackwell Publishing Ltd 2010 APMIS Vol.118 No.4

<P>Kim MS, Park SW, Kim YR, Lee JY, Lim HW, Song SY, Yoo NJ, Lee SH. Mutational analysis of caspase genes in prostate carcinomas. APMIS 2010; 118: 308–12.</P><P>Evasion of apoptosis is one of the hallmarks of cancer. Of the components of apoptosis machinery, caspases are the main executioners of apoptosis that initiate and propagate the apoptosis, and finally degrade target molecules. Caspase-encoding genes have been reported to harbor inactivating mutations in many human cancers. However, mutational status of caspase genes in prostate carcinomas has not been identified. The aim of this study was to explore whether caspase genes are somatically mutated in prostate carcinomas. For this, we analyzed entire coding regions of 11 human caspase-encoding genes (<I>CASP1–10</I> and <I>14</I>) in 45 prostate carcinoma tissues by a single-strand conformation polymorphism (SSCP) assay. In this study, however, we detected no somatic mutation of <I>CASP</I> genes in the prostate carcinomas by the SSCP. This is the first report on systematic evaluation of caspase-encoding gene mutations in human prostate carcinomas, and our data indicate that <I>CASP</I> genes may not be mutated in prostate carcinomas. The data suggest that apoptosis evasion in prostate carcinoma may be dependent on other mechanisms besides genetic alteration of caspase-encoding genes.</P>

Intravascular Papillary Endothelial Hyperplasia (Masson's Hemangioma) of the Liver: A New Hepatic Lesion

Cho Hyeon Min,Chin Hyung min,Park Il Young,Yoo Jin Young,Hwang Sung Soo,Kim Jun Gi,Park Woo Bae,Chun Chung Soo,Hong Seok Gi 대한의학회 2004 Journal of Korean medical science Vol.19 No.2