• 한국환경보건학회지
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• 제33권5호
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• pp.428-433
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• 2007

To clarify the pioneer group in the development of biofilms in high chlorine residual water, a semi-pilot model system was operated and 16S rDNA V3 targeted PCR-DGGE was submitted. Biofilm formation occurred rapidly in the model of a drinking water distribution system. It reached $10^3\;CFU/cm^2$ or more on the surface of stainless steel, PVC, and galvanized iron in chlorinated (1.0 mg/l) water within a week. Within a week, uncultured Proteobacteria- and Bacillales group-like sequences were detected and Sphingomonas-like sequences were identified from all season and all pipe materials tested. Hence Sphingomonas species were regarded as the potential pioneer group in the development of biofilm in drinking water and this results would be useful for the prevention of biofilm formation and safety of drinking tap water.

• 한국해양학회지
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• 제15권1호
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• pp.66-70
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• 1980

A method for the determination of dissolved species of Cd, Co, Cu, Ni, Pb and Zn in sea water by flame atomic absorption spectrophotometry (AAS) is described. Prior to analysis by AAS, these elements are concentrated by coprecipitation with iron pyrrolidinedithiocarbamate at pH 3 because of matrix effects and their low concentration levels in sea water. The detection limits are 0.01, 0.04, 0.02, 0.05, 0.08, and 0.03$\mu\textrm{g}$/l, and the relative standard deviations are 1.0, 2.4, 1.3, 2.9, 2.0 and 2.9% for Cd, Co, Cu, Ni, Pb and Zn, respectively. The method is shown to be satisfactory in terms of recovery and precision for the determination of these metals in sea water.

• 한국수산과학회지
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• 제7권4호
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• pp.229-233
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• 1974

1. 옥돔, 자리돔, 전복의 육질에 대한 무기질 성분을 정량하여 Table. 3과 같은 결과를 얻었다. 2. Copper, Phosphorus, Iron, Sodium, Calcium의 함량은 자리돔(정어), 옥돔(저어), 전복(패류)간에 뚜렷한 함량차이가 인정된다. 끝으로 이 실험은 1972연도 문교부 학술 연구 조성비로서 실시하였으며, 실험을 하는데 지도와 협조를 하여 주신 필현 교수와 허 종화 교수에 감사하는 바이다.

• 한국식품영양과학회지
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• 제26권5호
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• pp.851-859
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• 1997

This study was perfomed to investigate the contamination level of harmful heavy metals and the level of trace elements in 15 kinds of fish collected at the western coast in Korea from July to December in 1996. The levels of total lead, cadmium, mercury, iron, copper and zinc were determined and the results were summarized as follows: The minimum and maximum values(ppm) of fish, mean value bracketed, were ; Pb : 0.02~4.80(2.26), Cd: 0.001~0.54(0.04), Hg: 0.007~1.08(0.52), Fe: 7.76~66.39(25.70), Cu; 0.37~121.6(1.90), Zn:12.01~112.10(54.78). The results show that mean contents of Pb, Cd and Hg in 15 species fish were not yet dangerous levels enough to cause a health problem. But the contents of Pb and Hg tend to increase.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1996년도 정기총회 및 학술발표회
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• pp.30-30
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• 1996

A suproxide dismutase gene of Aquifex pyroprolus, a novel marine hypenhermophilic bacterium, was cloned, expressed, and characterized. The SOD of A pyrophilus (ApSOD) is an iron-containing homo-oligomeric protein with a monomeric molecular weight of 24.2 kDa. the amino acid sequence is similar to those of known Mn- and Fe-SODs from thermophilic archaea, and metal binding residues in all SOD sequences from different species are also conserved in A. pyrophilus SOD. (omitted)

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1195-1200
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• 2004

A fully coupled fluid flow, heat, and solute transport model was developed to investigate turbulent flow, solidification, and macrosegregation in a continuous casting process of steel slab with EMBR. Transport equations of mass, momentum, energy, and species for a binary iron-carbon alloy system were solved using a continuum model. The electromagnetic field was described by the Maxwell equations. A finite-volume method was employed to solve the conservation equations associated with appropriate boundary conditions. The effects of intensity of magnetic field and carbon segregation were investigated. The electromagnetic field reduces the velocity of molten flow in the mold and an increase in the percentage of C in steel results in a decrease of carbon segregation ratio.

• Bulletin of the Korean Chemical Society
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• 제19권8호
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• pp.840-846
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• 1998

The mechanism by which pyrrhotite is depressed by diethylenetriamine (DETA) during pentlandite flotation has been studied. Amyl xanthate is observed to adsorb on pyrrhotite to form both dixanthogen and iron xanthate. In the presence of DETA, the amount of xanthate adsorbed on pyrrhotite is substantially reduced as evidenced by infrared and UV/Vis spectroscopy. However, DETA does not adsorb on pyrrhotite as evidenced by infrared and X-ray photoelectron spectroscopy. DETA shifts the potential of the onset of xanthate adsorption on pyrrhotite by approximately 200 mV toward anodic direction, which is thought to be due to the increased solubility of surface oxidized species on pyrrhotite in the presence of DETA. A window of selectivity for the separation of pentlandite and pyrrhotite is provided by the results obtained in this study.

• 고신대학교 의과대학 학술지
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• 제33권2호
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• pp.135-140
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• 2018

Endometriosis is an estrogen-dependent chronic inflammatory condition that affects women in their reproductive period and is associated with pelvic pain and infertility. Oxidative stress (OS) occurs when reactive oxygen stress (ROS) and anti-oxidants are in imbalance. OS is a potential factor involved in the pathophysiology of endometriosis. Iron-induced ROS may trigger a chain of events resulting in the development and progression of endometriosis. Endogenous ROS are correlated with increased cellular proliferation and ERK1/2 activation in human endometriotic cells. An oxidative environment leads to stimulation of the ERK and PI3K/AKT/mTOR signaling pathways that facilitate endometriotic lesion progression through adhesion, angiogenesis, and proliferation. OS is also known to be involved in epigenetic mechanisms in endometriosis. We summarize the recent knowledge in our understanding of the role of oxidative stress in the pathogenesis of endometriosis.

• 한국광물학회지
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• 제16권1호
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• pp.107-123
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• 2003

본 연구는 0가 철 (ZVI)의 설치위치와 전극의 배열에 따른 다양한 조합의 전기적 투수성 반응벽을 대상으로 트리클로로에틸렌의 탈염소화 반응에 의한 정화시 ZVI의 부식에 기인하는 광물상침전물에 대해 알아보고, 이에 대한 조절 요소를 알아보고자 한다. 광물학적 연구 결과, 지하수 유입부의 ZVI 시료는 상대적으로 많은 레피도크로사이트, 훼리하이드라이트 혹은 철 수산화물과 (phospho)siderite가 산출되는 반면, 용출부의 ZVI 시료는 아카가나이트, 자철석/마그헤마이트, 그리고 중간 산물인 green rust (CR) I 과 CR II가 산출되었다. 이러한 광물 조합의 변화는 용존 산소 및 pH의 상승에 주로 기인한 것으로 나타났다. 또한 전기적 투수성 반응벽 내에 산출되는 광물상 침전물들의 조절 요소들은 (1) pH, (2) 용존산소, (3) 철의 부식시 중간 산물, (4) 음이온 종류 등으로 밝혀졌다.

• BMB Reports
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• 제50권2호
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• pp.103-108
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• 2017

Heme oxygenase (HO-1) catalyzes heme to carbon monoxide (CO), biliverdin/bilirubin, and iron and is known to prevent the pathogenesis of several human diseases. We assessed the beneficial effect of heme degradation products on osteoclastogenesis induced by receptor activator of NF-${\kappa}B$ ligand (RANKL). Treatment of RAW264.7 cells with CORM-2 (a CO donor) and bilirubin, but not with iron, decreased RANKL-induced osteoclastogenesis, with CORM-2 having a more potent anti-osteogenic effect. CORM-2 also inhibited RANKL-induced osteoclastogenesis and osteoclastic resorption activity in marrow-derived macrophages. Treatment with hemin, a HO-1 inducer, strongly inhibited RANKL-induced osteoclastogenesis in wild-type macrophages, but was ineffective in $HO-1^{+/-}$ cells. CORM-2 reduced RANKL-induced NFATc1 expression by inhibiting IKK-dependent NF-${\kappa}B$ activation and reactive oxygen species production. These results suggest that CO potently inhibits RANKL-induced osteoclastogenesis by inhibiting redox-sensitive NF-${\kappa}B$-mediated NFATc1 expression. Our findings indicate that HO-1/CO can act as an anti-resorption agent and reduce bone loss by blocking osteoclast differentiation.