Alcaligenes sp.의 PEG 6,000 분해에 관한 연구

이상준,박재림,박송희,이종근 부산대학교 환경문제연구소 1991 環境硏究報 Vol.9 No.-

The bacteria capable of utilizing polyethylene glycol(PEG) 6,000 as a sole carbon source was isolated from sewage water. This isolate designated as EL-031 was identified Alcaligenes sp. Alcaligenes sp. could grow on and degrade mono-, di-, tri-, tetraethylene glycol and PEG with molecular weight to 10,000, and very slowly utilize PEG 20,000. The growth rate of isolate increased in the higher molecular weight PEG 10,000. Isolate was very resistant to glyoxylic acid in basal medium up to 50mg of glyoxylic acid. However glyoxylic acid could not utilized as a carbon source. About 90% of PEG 6,000 was degraded in exponential phase of 48 h culture and PEG 6,000 was completely degraded during 72 h. In the biodegradability, this strain degrades lower molecular PEG previous to higher one on the PEG mixture, and PEG 6,000 was degraded lastly.

유한요소법을 이용한 단순인장 시험편의 탄소성파괴인성치 예측

선동주(D.J.Sun),박명균(M.K.Park),박세만(S.M.Bahk),최영택(Y.T.Choi) 한국자동차공학회 1997 한국자동차공학회 춘 추계 학술대회 논문집 Vol.1997 No.11_2

In oder to predict the elastic-plastic fracture toughness for metallic materials, Finite Element Method(FEM) was used for analysis of compact tension specimen. ASTM E399 test procedure was adopted for simulation of FEM. The Load-Crack Mouth Opening Displacement curve obtained from this analysis was used to detect the crack initiation point and determine the elastic-plastic fracture toughness J_IC. In order to prove the results, they were compared with the results from previous experiments and they agree with experimental results.

Regeneration of Fertile Transgenic Rice plants from a Korean Cultivar, Nakdongbyeo

Lee, S. I 한국식물조직배양학회 1995 식물생명공학회지 Vol.22 No.3

3차원 탄소성 유한요소법을 통한 금속복합재료와 지르코니아 접합체의 잔류응력해석

주재황,선동주,최영택,박세만,박명균 明知大學校 産業技術硏究所 1996 産業技術硏究所論文集 Vol.15 No.-

Employing a three dimensional finite element method a thermal elasto-plastic stress analysis was conducted to investigate residual stress distributions on the joining area between a ceramic(ZrO₂) and a SiC whisker-reinforced aluminum (Al composite). For purposes of comparisons, residual stresses at the interfaces on the joining area were first analyzed for varying volume fractions of SiC whiskers utilizing two dimensional elasto-plastic models. The results from the 2-D models were compared with those from 3-D models to understand the Practical nature of residual stresses produced during industrial joining processes for ceramics and metal matrix composites. Additionally, the same procedures were applied to compute stress variations along a line passing through the joining area to obtain a physical insight and to offer a plausible explanations for fracture patterns occuring at the interfaces during bending.

티프스 간의 주사소견과 간혈류 동태

이문호,박용휘,안재성 대한핵의학회 1970 핵의학 분자영상 Vol.4 No.2

교양 198금을 이용하여 장티푸스로 확진된 환자 14례의 간주사소견과 혈중제거율치를 각각 분석 검토하였다. 간주사상에서 간과 비장의 종대는 각각 78.6%와 64.3%로 나타났으며, 간외 방사능섭취는 비장에서 78.6%, 척수에서 57.1%로 나타났다. 간 및 비장종대가 있고 동시에 간외 방사능섭취가 나타난 예는 57.1%이었다. 이는 티프스간염의 특징인 망상내피세포 탐식능의 항진에 따르는 변화로 생각된다. 혈중제거율치는 각례마다 발병후 경과된 날자별로 자세히 검토한 결과, 발병후 10일 사이에 현저히 촉진되는 것을 알 수 있었다. 이는 티프스간염 초기에 간 혈류량이 증가하는 것을 가리키는 것으로 판단된다. 즉, 198금을 사용한 주사사진에서 간 및 비장의 종대가 보이고 비장 또는 척수에 의한 간외 방사능섭취가 나타나며 혈중제거율치가 촉진되어 있는 것은 티프스 간염에 고유한 일련의 소견으로 믿는다. Fourteen patients with typhoid fever studied by scanning and clearance-rate measurements of subcritical dose colloidal radiogold(198Au). Mild to moderate enlargement of the liver and spleen was noted in 78.6 and 64.3 percent of patients, respectively; and splenic and spinal bone-marrow uptake was seen in 78.6 and 57.1 percent of cases, respectively. Typically, these scan changes occurred concomitantly (57.1%) and are considered to represent increased phagocytic activity of the RE cells which is characteristic of typhoid fever. The half clearance-time was significantly shortened during the first 10-day period of the illness indicating an increase in the hepatic blood in the early phase of typhoid infection. Hepatomegaly, splenomegaly and extrahepatic uptakes along with an accelerated (or less a normal) clearance time are characteristic of typhoid fever.

1.88A GeV ^56Fe 중이온에 의해 원자핵건판 내에서 회절들뜸 및 준회절들뜸 기구로 생긴 다중발생

김종오,김태연,천병구,박인곤,송진섭,윤천실,박상렬,이경언,김재률,김태익,박명렬,임인택,장한일,박복남 慶尙大學校 기초과학연구소 1990 基礎科學硏究所報 Vol.6 No.-

원자핵건판 내에서 1.88A GeV의 에너지를 갖는 ^56Fe 중이온(heavy ion)의 평균자유행로는 비적추적법(along-the-track scanning method)을 사용하여 8.01±0.27㎝로 측정되었다. ^56Fe 주이온에 의한 회절들뜸반응을 KHP 판정법으로 찾아내었으며, 회절들뜸반응에 대한 평균자유행로는 0.86±0.10m로 측정되었다. 입사중이온의 정지계 내에서 ^56Fe 중이온에 의한 80개의 회절들뜸 및 준회절들뜸반응에 대한 알파입자와 단일하전 입자의 의사신속도 분포는 각각 (γ_a-η_b)_max=3.31, (γ_a-η_b)_max=2.30에서 최대값을 갖는 가우스분포함수 형태를 이루었다. By employing the method of along-the -track scanning. the mean free path of inelastic collisions for 1.8A GeV^56Fe heavy ion in nuclear emulsion is measured to be 8.01±0.27㎝. "Diffractive Excitation" events are identified by using the KHP method and the mean free path of diffractive excitation is measured to be 0.86±0.10m. The distributions of pseudorapidities of alpha and singly-charged fragments for diffractive excitation of 1.88A GeV ^Fe heavy ion are well fitted by Gaussian distribution function with peaks having (γ_a-η_b)_max=3.30 and (γ_p-η_b)_max=2.24.

AtBAG6, a novel calmodulin-binding protein, induces programmed cell death in yeast and plants

Kang, C H,Jung, W Y,Kang, Y H,Kim, J Y,Kim, D G,Jeong, J C,Baek, D W,Jin, J B,Lee, J Y,Kim, M O,Chung, W S,Mengiste, T,Koiwa, H,Kwak, S S,Bahk, J D,Lee, S Y,Nam, J S,Yun, D J,Cho, M J Nature Publishing Group 2006 CELL DEATH AND DIFFERENTIATION Vol.13 No.1

Calmodulin (CaM) influences many cellular processes by interacting with various proteins. Here, we isolated AtBAG6, an Arabidopsis CaM-binding protein that contains a central BCL-2-associated athanogene (BAG) domain. In yeast and plants, overexpression of AtBAG6 induced cell death phenotypes consistent with programmed cell death (PCD). Recombinant AtBAG6 had higher affinity for CaM in the absence of free Ca<SUP>2 +</SUP> than in its presence. An IQ motif (IQXXXRGXXXR, where X denotes any amino-acid) was required for Ca<SUP>2 +</SUP>-independent CaM complex formation and single amino-acid changes within this motif abrogated both AtBAG6-activated CaM-binding and cell death in yeast and plants. A 134-amino-acid stretch, encompassing both the IQ motif and BAG domain, was sufficient to induce cell death. Agents generating oxygen radicals, which are known to be involved in plant PCD, specifically induced the AtBAG6 transcript. Collectively, these results suggest that AtBAG6 is a stress-upregulated CaM-binding protein involved in plant PCD.Cell Death and Differentiation (2006) 13, 84–95. doi:10.1038/sj.cdd.4401712; published online 8 July 2005

Performance and simulation of a double gap resistive plate chamber in avalanche mode

S.H. Ahn,Byungsik Hong,B.I. Kim,D.G. Koo,D.H. Moon,H.W. Lee,J.H. Kim,J.K. Lim,J.T. Rhee,K.B. Lee,K.S. Sim,K.S. Lee,M. Ito,M.S. Ryu,S. Park,S.J. Hong,S.J. Lee,S.K. Nam,S.Y. Bahk,T.I. Kang,W.J. Park,Y.J 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.45 No.3

We present a detailed analysis of the time and the charge signals of a prototype double-gap resistive plate chamber for the endcap region of the Compact Muon Solenoid (CMS) detector at the Large Hadron Collider (LHC). The chamber was built with relatively low-resistivity bakelite. The time and the charge results demonstrate that the high-voltage plateau, which satises various CMS requirements for the eciency, the noise cluster rate, the fraction of the large signal, and the streamer probability, can be extended at least up to 400 V with the present design. In addition, a simple avalanche multiplication model is studied in detail. The model can reproduce the experimental charge spectra reasonably well. The charge information enables us to estimate the eective Townsend coecient in avalanche-mode operation.

Paleoceanographic implications and cyclostratigraphy of variations in well-log data from the western slope of the Ulleung Basin, East Sea

Bahk, J.J.,Um, I.K.,Yi, B.Y.,Yoo, D.G. Pergamon Press 2016 QUATERNARY INTERNATIONAL Vol.392 No.-

<P>Cyclic variations of density and gamma-ray logs achieved from the two drill sites of UBGH2-1_1 and UBGH2-1_2 in the western slope of the Ulleung Basin were investigated to reveal their paleoceanographic implications and establish cyclostratigraphy of the well logs. Integration of the core, log, and seismic data from the two sites indicates that the sediments of the drilled intervals mostly consist of hemipelagic muds, with a few sporadic mass transport deposits intercalated only in the downslope site of UBGH2-1_1. Comparison with variations in sediment composition suggests that ratios of terrigeneous to biogenic materials which were modulated by orbital-scale climate changes should be responsible to the well-log variations. The established cyclostratigraphy of the well logs based on correlation with marine oxygen isotope records indicates such climatic modulation of the sedimentation in the western slope of the Ulleung Basin has persisted at least since 2.6 Ma, consistent with the variation reported from the Oki Ridge. (C) 2015 Elsevier Ltd and INQUA. All rights reserved.</P>

Exposure assessment for Bacillus cereus in ready-to-eat Kimbab selling at stores

Bahk, G.J.,Todd, E.C.D.,Hong, C.H.,Oh, D.H.,Ha, S.D. Butterworths ; Taylor Francis ; Elsevier Science 2007 FOOD CONTROL Vol.18 No.6

Kimbab, which is rolled cooked-rice and other foodstuffs in dried laver, is a representative ready-to-eat (RTE) food in Korea. Bacillus cereus is a significant hazard associated with Kimbab. However, the knowledge of the dose-response relationship for B. cereus is limited, now it is not possible to conduct a full microbial risk assessment. Therefore, our study may be focused on the exposure assessment from retail store to the point of consumption in a Kimbab contaminated with B. cereus. The survey data for preparing and selling of Kimbab, predictive growth model, and consumer eating patterns were combined with probabilistic modeling to simulate the level of B. cereus in store Kimbab at the time of consumption. The estimated contamination levels ranged from as minimum (5% percentile) -3.63logcfu/g, median (50% percentile) 1.39logcfu/g, mean 1.57logcfu/g, and a maximum (95% percentile) 7.31logcfu/g. However, there is always a paucity of data to conduct such full exposure assessments with associated variability and uncertainty, coupled with a validation step. Therefore, we suggest that additional studies to allow for a more realistic and accuracy exposure assessment in the future, based on data gaps we identify.