Ce$O_2$첨가 및 분말처리가 U$O_2$ 분말의 소결에 미치는 영향

김형수,이영우,최창범,양명승,전풍일,Kim, Hyeong-Su,Lee, Yeong-U,Choe, Chang-Beom,Yang, Myeong-Seung,Jeon, Pung-Il 한국재료학회 1993 한국재료학회지 Vol.3 No.3

순수 $UO_2$에 첨가량 변화 및 ball-milling 시간에 따른 (U, Ce)$O_2$ 분말의 특성과 각 조건별로 제조된 분말을 압분 및 소결하여 (U, Ce)$O_2$ 분말 특성에 따른 소결성을 비교 조사하였다. 실험 결과로 부터 ball-milling시간이 길어짐에 따라 입자들은 미세화되고, Ce$O_2$ 함량이 증가할수록 압분, 소결밀도는 저하 하였으며, $CeO_2$는 소결성을 저하시키는 산화물임을 확인하였다. 10wt%,$CeO_2$ 가 첨가된 (U, Ce)$O_2$ 분말의 경우, ball-milling 4시간 수행한 분말의 소결체가 기공의 수도 적고, 구형에 가까왔으며, 소결밀도가 가장 높았다. 이는 4시간 ball-milling한 (U, Ce)$O_2$분말이 비표면적이 크로 그의 packing ratio가 적절하였기 때문이다. We investigated the changes of (U, Ce)$O_2$ powder characteristics with $CeO_2$ contents and ball-milling time and then studied on the sintering properties with those (U, Ce)$O_2$ powder characteristics. From the results of this study, it was concluded that the longer ball-milling time of (U, Ce)$O_2$ powder was, the finer its particle size was. Green and sintered densities were decreased with $CeO_2$ contensts increase. And also $CeO_2$ was recongized deteriorating oxide on the $UO_2$ sintering. In case of the lOwt. % $CeO_2$ contents, (U, Ce)$O_2$ sintered pellet which was made of ball-milled powder for 4 hours had few pores and its pores got near to the sphere. And its sintered density had the highest. Because its powder had higher surface area and its packing ratio was appropriated much better than others.

Stereological Analysis on Migration of Human Neural Stem Cells in the Brain of Rats Bearing Glioma

Kim, Jae-Ho,Lee, Jong-Eun,Kim, Seung U.,Cho, Kyung-Gi Oxford University Press 2010 Neurosurgery Vol.66 No.2

<P>OBJECTIVE: The objective of this study was to determine the rate and pattern of NSC migration in the brain and its time course after NSC transplantation. METHODS: We investigated the tropism of HB1.F3 (F3) immortalized human NSCs in rats bearing U373 human glioma in the brain. Rats received an injection of human U373MG malignant glioma cells into the striatum followed by an injection of F3 cells into the contralateral hemisphere 7 days later. We analyzed the numbers, distribution, and migration rate of NSCs using unbiased stereology. RESULTS: Approximately 10% of the injected NSCs migrated into the tumor region by 50 minutes after NSC injection. The number of NSCs in the tumor region increased slowly up to 5 days post-injection and increased significantly up to 15 days post-injection. Changes in tumor volume showed similar patterns. The rate of NSC migration was approximately 175 microm/min. NSCs increased in number approximately 1.7-fold during day 1 in the absence of tumor cell inoculation in vivo. However, the proliferation of NSCs began to decline after 5 days after injection. CONCLUSION: We identified for the first time the rate and pattern of NSC migration to the tumor mass in vivo. These findings may provide useful information with respect to preclinical research of gene therapy for malignant gliomas.</P>

Clinical characteristics of patients with psoriasis with high serum total immunoglobulin E: A retrospective single-center study

( Seung Hui Seok ),( Tae Bin Im ),( Jung U Shin ),( Hee Jung Lee ),( Moon Soo Yoon ),( Dong Hyun Kim ) 대한피부과학회 2020 대한피부과학회 학술발표대회집 Vol.72 No.1

Background: Psoriasis is a chronic T17 cells-driven immune-mediated inflammatory disease. However, psoriasis patients may have elevated serum total immunoglobulin E (IgE), which is a hallmark of Th2 inflammation. In previous case reports, patients with psoriasis with high serum IgE levels did not respond well to treatment or exacerbated eczema lesions. Objectives: We sought to investigate the clinical characteristics of psoriasis patients with high serum total IgE levels. Methods: This is a retrospective chart review of 130 patients with plaque psoriasis who had done serum total IgE level test from November 1, 2009, to October 31, 2019. We compared the demographics, clinical characteristics, severity of the disease, and treatment regimen for each high IgE group (>214 U/mL), and normal IgE group (≤214 U/mL). Results: Among 130 patients with psoriasis, 41 patients (31.5%) had high serum IgE level. High IgE levels were positively associated with the severity of disease and psoriasis lesions including scalp, hands, feet, and flexures which are difficult-to-treat were observed significantly higher in patients with high serum IgE level. There was no correlation between age, gender, disease duration, or presence of pruritus, and serum total IgE level. Conclusion: High serum IgE levels in psoriasis may be a prognostic factor which is related with more severe and difficult-to-treat traits requiring systemic treatment.

19세기말 『미국민속학보(the Journal of American Folklore)』에 소개된 한국시가의 특징

김승우(Kim, Seung-u) 우리문학회 2013 우리文學硏究 Vol.0 No.40

본고는 19세기말 『미국민속학보』에 수록된 한국 관련 논문들의 분포를 개관하고, 그 가운데 가장 주목되는 애나 스미스의 「몇 편의 한국 자장가(Some Nursery Rhymes of Korea)」를 분석함으로써 당시 서구 학계에 한국시가가 어떠한 방식으로 소개되었는지 그 궤적을 살피는 데 목적을 둔다. 애나 스미스는 미국 연방정부에서 교육 행정가로 활동한 여성 명사였다. 특히 스미스가 담임했던 분야는 해외의 교육 정책이었기 때문에 한국에 대해서도 예사 이상의 관심을 보였던 것으로 파악된다. 이처럼 여성으로서, 또한 해외의 교육 문제를 다루는 관료로서 스미스의 관심사가 중첩되면서 한국 어머니들의 모성과 교육적 가치가 응축되어 있는 자장가(nursery rhymes)를 논의의 대상으로 포섭해 들일 수 있었던 것이다. 따라서 그의 글에서는 한국의 자장가로부터 도출해 낼 수 있는 한국인의 전통적 인간관과 세계관 및 교육관이 시종 중시되었다. 스미스가 특히 주목했던 사항은 내세보다는 현세에서 자식이 출사하고 영달하기를 기원하는 어머니의 ‘실용적 충동’과 그러한 출사를 가능케 하는 기반으로서의 도덕적ㆍ인격적 수양, 입신양명의 유가적 기원과 자연스레 융합된 인과응보의 불교적 기원, 가족 관계와 가족 제도가 안정적으로 지속되기를 바라는 마음 등이었다. 한편, 스미스의 글에서 또 한 가지 두드러지는 내역은 한국시가의 율격적 특성에 대한 언급이 이루어졌다는 점이다. 그는 한국시가에서는 음절의 강약이 율격의 기저로 활용되지 않는다는 점을 확인하고서 강약률 이외의 율격모형을 모색하였으며, 그 귀착점으로 장단율을 하나의 가설로 설정하기에 이른다. 이상과 같은 스미스의 논의는 체계화된 자료 조사나 분석에 의거한 것이기 보다는 대개 개인적인 인상과 추정을 바탕으로 이루어진 것이었고, 따라서 그 학술적 의의 역시 제한적일 수밖에 없다. 그러나 스미스의 글은 미국의 유력 학술지인『미국민속학보』에 수록되었기 때문에 폭넓은 독자층을 확보할 수 있었을 뿐만 아니라, 서구 학자와 지식인들의 뇌리에 한국의 문화적 특질을 각인하는 데에도 중요한 영향을 미쳤을 가능성이 높다. 요컨대 애나 스미스의 고찰은 그 적부를 차치하고라도 한국시가가 서구 학계에 소개되던 궤적과 방식을 보여준다는 점에서 각별한 의미가 있으며, 이 같은 의미에 입각하여 그의 작업이 정당하게 평가되어야 할 것이다. This article aims to take a general view of the papers on Korea in the Journal of American Folklore in the late nineteenth century and to examine how Korean poetry was introduced to the western academic world by particularly analyzing Anna Tolman Smith’s “Some Nursery Rhymes of Korea,” which is regarded as the most important writing of them. Smith was a distinguished woman as an executive official engaging in foreign educational systems in the U.S. federal government, so it is likely that her interest as a woman and specialist in foreign education led her to inquire Korean traditional nursery rhymes which essentially reflect Korean mothers’ hope and lessen to their children. Consequently, she throughout tried to deduce Korean people’s view of life, the world, and education from several nursery songs. What she specially mentioned are Korean women’s ‘practical’ wish for their children’s success not in the world beyond the grave but in this world, and their serious consideration for the ethical value. Besides, she also paid attention to Koreans’ Buddhistic religion combined with Confucianism, and their inclination to maintain the traditional family system. Meanwhile, it is notable that she managed to conceptualize the versification structure of Korean poetry. After she found out that the stress of the syllables is not necessarily associated with the rules of the versification of Korean verses, she spotted the length of the syllables as the primary factor that makes the rhythm in Korean language and poetry. Strictly speaking, Smith’s inquiry into Korean poetry lacked scholarly exactitude since her study was based mostly on personal speculation rather than on thorough analyses. Nonetheless, because her paper appeared in the Journal of American Folklore, one of the most potent academic journals at that time in the U.S., it could have not only a large circle of subscribers but also a great influence on western intellectuals’ understanding of Korean culture. Such a feature made her writing acquire a certain level of importance which has not been found in the preceding westerners’ studies of Korean poetry.

혈중 총 면역글로불린 E가 증가된 건선 환자의 임상적 특징: 후향적 단일기관 연구

석승휘 ( Seung Hui Seok ),임태빈 ( Tae Bin Im ),신정우 ( Jung U Shin ),이희정 ( Hee Jung Lee ),윤문수 ( Moon Soo Yoon ),김동현 ( Dong Hyun Kim ) 대한피부과학회 2021 대한피부과학회지 Vol.59 No.2

Background: Psoriasis is a chronic T17 cell-driven immune-mediated inflammatory disease. However, patients with psoriasis may have elevated total serum immunoglobulin E (IgE) levels, which is a hallmark of Th2 inflammation. In previous case reports, psoriasis patients with elevated total serum IgE levels did not respond well to treatment or had exacerbated eczema lesions. Objective: We sought to investigate the clinical characteristics of psoriasis patients with elevated total serum IgE levels. Methods: This is a retrospective chart review of 130 patients with psoriasis who were tested for total serum IgE levels from November 1, 2009, to October 31, 2019. We compared the demographics, clinical characteristics, disease severity, and treatment regimen for each elevated IgE group (>214 U/mL) and normal IgE group (≤214 U/mL). Results: Among 130 patients with psoriasis, 41 (31.5%) had elevated total serum IgE levels. Elevated total serum IgE levels were positively associated with the severity of disease; psoriasis lesions including those on the scalp, hands, feet, and flexures, which are difficult to treat, were observed to be significantly higher in patients with elevated total serum IgE levels. There was no correlation between age, sex, disease duration, or presence of pruritus and total serum IgE levels. Conclusion: This study identified the clinical characteristics of psoriasis patients with elevated total serum IgE levels in Korea. (Korean J Dermatol 2021;59(2):94∼99)

Downregulation of GFAP, TSP-1, and p53 in human glioblastoma cell line, U373MG, by IE1 protein from human cytomegalovirus

Lee, Karim,Jeon, Kipyoung,Kim, Jong-Mook,Kim, Vic Narry,Choi, Dong Hee,Kim, Seung U.,Kim, Sunyoung John Wiley & Sons, Inc. 2005 Glia Vol.51 No.1

<P>Human cytomegalovirus (HCMV) is a member of the β-herpesvirus family, which has tropism for glial cells. It was recently reported that HCMV might play important roles in the pathogenesis of malignant glioma. In this study, we investigated the effects of the HCMV IE1 protein on the gene expression profile in the human glioblastoma cell line, U373MG by employing cDNA microarray technology. Using DNA chips containing approximately 1,000 human cDNAs, RNA samples from U373MG cells stably expressing IE1 were compared with those from the control cells lacking IE1 cDNA. Fluorescence intensities of 13 genes were significantly decreased in IE1-expressing cells, while one gene was found to be upregulated. Among these 14 genes, we chose to work further on glial fibrillary acidic protein (GFAP), thrombospondin-1 (TSP-1), and p53, because of their previously known involvement in tumorigenesis. The mRNA levels of all these genes were found to be decreased in IE1-expressing glioblastoma cells by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) as well as Northern blot analysis. The decreased expression of these genes was also observed at protein levels as measured by immunocytochemistry or fluorescence-activated cell sorting (FACS) analysis. Our data strongly suggested that HCMV IE1 could modulate the expression of cellular genes that might play important roles in the pathogenesis of glial tumors. © 2005 Wiley-Liss, Inc.</P>

Zinc stearate의 첨가가 $UO_{2}$분말의 겉보기밀도, 혼합 및 성형에 미치는 효과

나상호,김시형,이영우,양명승,손동성,Na, Sang-Ho,Kim, Si-Hyeong,Lee, Yeong-U,Yang, Myeong-Seung,Son, Dong-Seong 한국재료학회 1995 한국재료학회지 Vol.5 No.4

윤활제인 zinc stearate의 첨가량 (0~4wt%)을 변화시켜 U$O_{2}$분말의 겉보기밀도, 성형시의 분말입자간 마찰과 입자/다이벽 마찰간의 상관관계를 조사하였다. 소량의 윤활제 첨가시에는 U$O_{2}$분말입자간 박막의 윤활제 도포층이 형성되어 겉보기밀도가 증가한 반면 다량의 윤활제를 첨가한 경우에는 U$O_{2}$ 분말입자에 두꺼운 윤활제 도포층이 형성되고 미혼합된 윤활제가 존재하여 겉보기밀도는 감소하는 경향을 보였다. 윤활제를 첨가혼합한 상태에서 다이벽 윤활도포 유무에 따라 구한 U$O_{2}$ 성형체의 성형압력/성형밀도 자료로부터 분말입자간 마찰, 입자/다이벽 마찰 그리고 성형시 lubrication/inhibition등의 상대적 중요성을 조사하였다. 입자/다이벽 마찰에 의한 압력손실은 입자간 마찰에 의한 압력손실보다 크게 나타났다. 입자/다이벽 마찰에 의한 압력손실은 다이벽 윤활제 도포에 의해 최소화될 수 있지만 상대적으로 바람직하지 않은 성형시의 inhibition이 야기되는 것으로 나타났다.

SiO₂첨가량에 따른 SnO₂계 세라믹 복합체의 CO, H₂가스 감응특성

김태원,최우성,정승우 경북대학교 센서기술연구소 1997 센서技術學術大會論文集 Vol.8 No.1

In this work, we fabricated 0~20mol% SiO_(2) added SnO_(2) composite ceramics of bulk type to investigate the CO and H_(2) gas sensitivity in various composition, temperature, and concentration of CO and H_(2) gas. The mearsured 100ppm and 250ppm CO gas sensitivities of SiO_(2)-SnO_(2) composite ceramics were about 1~7.62 and 1~5.61, respectively. These values were about 1~1.5 times larger than pure SnO_(2). In particular, at 325℃, the maximum CO gas sensitivity of 20 mol% added SiO_(2) was 7.6 in 1000 ppm CO gas atmosphere. In the other hand, 1000ppm and 500ppm H_(2) gas sensitivities of SiO_(2)-SnO_(2) composites were about 2.93~21.17 and 2.12~11.34, respectively. In addition, at 325℃, 1000 and 500 ppm H_(2) gas sensitivities were about 21.17 and 11.34, respectively.

유리치은이식술의 임상증례

김유석,황규영,정승우 조선대학교 구강생물학연구소 2003 Oral Biology Research (Oral Biol Res) Vol.27 No.1

The free gingival graft has proven to be a predictable procedure for obtaining an increased width of attached gingiva, concomitantly increasing vestibular depth and eliminating the tension of an abnormal frenulum, and root coverage. The free gingival grafts is needed when the patient experiences discomfort during toothbrushing due to gingival recession and chewing due to an interfering lining mucosa and/or when the margin of restoration is placed in a subgingival position at sites with a thin gingiva that may favor an inflammatory tissue reaction in the presence of subgingival plaque. In this study, two patients were treated by the free gingiva1 grafts. One patient had no attached gingiva at lower left 2nd premolar, 2nd molar which were treated subgingival restoration and more inflammatory. The free gingival grafts were performed in this sites. The 1-2㎜ attached gingiva were obtained and maintained after 4monthes. The other had 3-4㎜ gingival recession at lower left 1st, 2nd premolar and experiences discomfort during toothbrushing, cold hypersensitivity. The free gingival grafts were performed in this sites. The 2-3㎜ root coverage were obtained and maintained after 30 months. The free gingival graft for increasing width and thickness of gingiva can be performed in case of subgingival restorations , gingival recession.

컴퓨터 작업 시 의자 등받이 위치가 근육 활성도에 미치는 영향

김민우,변승진,이경은,정소영,조주영,최원자,최찬양,김경 대구대학교 특수교육재활과학연구소 2011 再活科學硏究 Vol.29 No.1

이 연구는 컴퓨터 작업시 의자 등받이 위치가 근육활성도에 미치는 영향을 알아보기 위해 36명의 근골격에 문제가 없는 성인 남녀가 참가하였으며 대상자들은 등받이가 뒤에 있는 의자와 등받이가 없는 의자, 등받이가 앞에 있는 우리들 의자를 무작위로 배정하고 동일한 컴퓨터 작업을 실시하게 하였다. 실험 중, 표면근전도기를 사용하여 의자에 따른 위등세모근, 머리널판근 그리고 척주세움근의 근활성도 변화를 측정하였다. 이 연구의 결과를 종합해보면 등받이가 앞에 있는 의자는 허리 근육의 부담을 줄이지만 목근육에 부담이 늘어나고 등받이가 뒤에 있는 의자와 없는 의자는 허리근육에는 다소 무리가 가지만 목근육에는 부담이 덜하다는 것을 알 수 있었다. 이러한 결과로 환자의 증상에 다라 컴퓨터 작업을 하는 동안 의자 등받이의 위치를 조절하여 치료에 도움이 될 수 있다고 생각되어진다. Objective : In this study, we checked and observed people's change of body muscle and muscle activity who do computer work on different chairs. We set three kind of chairs which one is a stool and another one is the back is fixed, and the other one is the back is fixed in front of chair. Subject : Accounting for 36 health men and women, we divided these people to 3 groups and put them on the three cases(position 1, position 2, position 3). We measured muscle activity of upper trapezius, Splenius Cervics, Erector Spinae from the groups by using surface electromyogram system. Methods : The standard of the electromyogram was 'reference voluntary contraction', and we carried out 'one way anova' to compare muscle activity of three groups. Results : In position 1, reference voluntary contraction of upper trapezius muscle activity was 123.2821%, Splenius Cervics was 141.7526%, and Erector Spinae was 254.5233%. In position 2, reference voluntary contraction of upper trapezius muscle activity was 132.9395%, Splenius Cervics was 141.7526%, and Erector Spinae was 246.6540%. In position 3, reference voluntary contraction of upper trapezius muscle activity was 190.6487%, Splenius Cervics was 270.2332%, and Erector Spinae was 182.1021%. Both upper trapezius and Splenius Cervics muscle activity of position 3 group was higher than the others groups. In position 1 group, Erector Spinae muscle activity was hight than the other groups. And either was position 2 group's(p<0.05). Conclusion : Therefore the chair which is the back is fixed in front is more comfortable for waist muscle but it's not good for neck. And the other chairs are better in waist muscle but not in neck muscle. So far, when we do a computer work, it's prefer to sit on the group 1&2's chairs to reduce neck muscle's stress and sit on group 3's chair to reduce waist muscle's stress.