• 한국대기환경학회지
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• 제20권5호
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• pp.625-632
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• 2004

Perfluorocompounds ($PFC_s$), such as tetrafluoromethane ($CF_4$) and hexafluoroethane ($C_2F_6$), have been widely used as plasma etching and chemical vapor deposition (CVD) gases for semiconductor manufacturing processes. Since these $PFC_s$ are known to cause a greenhouse effect intensively, there has been a growing interest in reducing $PFC_s$ emissions. Among various $CF_4$ decomposing techniques, a dielectric barrier discharge (DBD) is considered as one of a promising candidate because it has been successfully used for generating ozone ($O_3$) and decomposing nitrogen oxide (NO). Firstly, optimal concentration of oxygen for $CF_4$ decomposition was found to figure out how many primary and secondary reactions are associated with DBD process. Secondary, to find effective discharge method for $CF_4$ decomposition, a streamer and a glow mode in DBD are experimentally compared, which includes (i) coaxialcylinder DBD, (ii) DBD reactor packed with glass beads. and (iii) a glow mode operation with a helium gas. The test results showed that optimal concentration of oxygen was ranged 500 ppm~1% for treating 500 ppm of $CF_4$ and helium glow discharge was the most efficient one to decompose $CF_4$.

• Molecular & Cellular Toxicology
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• 제3권4호
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• pp.254-261
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• 2007

20-O-($\beta$-D-Glucopyranosyl)-20 (S)-protopanaxadiol (IH-901) is one of the major metabolites of ginsenosides from Panax ginseng, and is suggested that IH-901 has been associated with various pharmacological and physiological activities. In this study, we demonstrate that IH-901 induced anti-inflammation in HT-29 human colon adenocarcinoma cells. Our results showed that IH-901 inhibited cell proliferation of HT-29 in a time- and dose-dependent manner. We also found that IH-901 was significantly decreased expression of iNOS compared with non-treated. We observed effect of IH-901 related with inflammatory genes using by cDNA microarray. We were known that the 34 inflammatory genes such as E2F, CDK6, TNF-$\alpha$, and PKC were down-regulated. Thus, these results suggest that IH-901 may have a potential preventive factor to improving cancer induced by chronic inflammation.

• 대한바이러스학회지
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• 제29권3호
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• pp.165-174
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• 1999

To investigate viral pathogenesis and in vivo efficacy of acyclovir (ACV) in mouse HSV-1 encephalitis models, female BALB/c mice aged 5 weeks were inoculated with strain F either intranasally (IN) or intracerebrally (IC). ACV-treatment by intraperitomeal injection with 0, 5, 10 and 25 mg/kg b.i.d. for 6 days was commenced 1 h after infection. Body weight and signs of clinical disease were noted daily up to 2 weeks. $ED_{50}$ of ACV in IN infection was <5 mg/kg and 14.1 mg/kg in IC infection. Tissues of central nervous system were collected from 2 mice per group everyday up to 5 day p.i. and the virus titers were measured. In IN infection model, high titers in eyes and trigeminal nerves were observed. ACV-treatment showed significant reduction of the titers in all the isolated. In IC infection model, cerebrum, cerebellum and brain stem showed high virus titers. ACV-treatment showed less significant reduction of virus titers than that in IN infection model. Reactivation of explanted trigeminal nerves from mice 30 day p.i. was monitored. In all of ACV treated mice reactivation was observed, i.e. even the highest dose of ACV did not inhibit the establishment of viral latency.

• ALGAE
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• 제25권4호
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• pp.187-195
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• 2010

The genus Rosenvingea is well known in the tropics. Four species have been reported from Pacific Mexico: R. floridana, R. antillarum, R. intricata and R. sanctae-crucis. We collected a plant (Boca del Cielo, Chiapas) that we identified as Rosenvingea orientalis, a species not previously reported from Pacific Mexico. We were able to characterize the life cycle of this species for the first time in laboratory culture. It reproduced exclusively by plurilocular sporangia (plurangia). The mature plants were up to 6 cm long with cylindrical to compressed fronds (to 2 mm wide) with dichotomous branches in the upper half of the thallus. The medulla was hollow with 2-3 layers of large inflated colourless cells at the periphery. The cortex was comprised of 1 layer of small cells, each with a single chloroplast and pyrenoid. Linear plurangial sori with phaeophycean hairs formed along the mature fronds. Zoospore germlings developed into prostrate filamentous systems, each with a single phaeophycean hair that gave rise to a single erect shoot with multiple hairs arising near the tip. Molecular phylogeny using the psaA gene placed this isolate within the Scytosiphonaceae. It does not confirm the exact identification of R. orientalis, although its placement close to other Rosenvingea sequences was confirmed and morphological evidence supports its placement in R. orientalis. Our culture investigations indicated that it has an asexual life cycle. Further collections are needed to resolve the full generic and specific relationships of Rosenvingea and related taxa, and their reproductive patterns.

• 환경영향평가
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• 제15권6호
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• pp.373-383
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• 2006

The spatial mapping of risk is very useful data in planning for disaster preparedness. This research presents a methodology for making the landslide life risk map in the Boeun area which had considerable landslide damage following heavy rain in August, 1998. We have developed a three-stage procedure in spatial data analysis not only to estimate the probability of the occurrence of the natural hazardous events but also to evaluate the uncertainty of the estimators of that probability. The three-stage procedure consists of: (i)construction of a hazard prediction map of "future" hazardous events; (ii) validation of prediction results and estimation of the probability of occurrence for each predicted hazard level; and (iii) generation of risk maps with the introduction of human life factors representing assumed or established vulnerability levels by combining the prediction map in the first stage and the estimated probabilities in the second stage with human life data. The significance of the landslide susceptibility map was evaluated by computing a prediction rate curve. It is used that the Bayesian prediction model and the case study results (the landslide susceptibility map and prediction rate curve) can be prepared for prevention of future landslide life risk map. Data from the Bayesian model-based landslide susceptibility map and prediction ratio curves were used together with human rife data to draft future landslide life risk maps. Results reveal that individual pixels had low risks, but the total risk death toll was estimated at 3.14 people. In particular, the dangerous areas involving an estimated 1/100 people were shown to have the highest risk among all research-target areas. Three people were killed in this area when landslides occurred in 1998. Thus, this risk map can deliver factual damage situation prediction to policy decision-makers, and subsequently can be used as useful data in preventing disasters. In particular, drafting of maps on landslide risk in various steps will enable one to forecast the occurrence of disasters.

• Asian-Australasian Journal of Animal Sciences
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• 제11권1호
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• pp.1-7
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• 1998

A total of 120 pigs $(L\;{\times}\;LW\;{\times}\;D)$ averaged 14.16 kg of body weight were reared under six dietary treatments to evaluate the effects of amino acid supplementation on their performances. Treatments were 1) 18% CP diet (control); 2) 15% CP+0.28% Lys (B, 15L); 3) B+0.06% Met (15LM); 4) B+0.13% Thr (15LT) ; 5) B+0.06% Met+0.13% Thr (15LMT); 6) B+0.06% Met+0.13% Thr+0.05% Trp (15LMTT). Each treatment had 4 replicates with 5 pigs per replicate. The daily weight gains were statistically similar in 15LMT, 15LMTT and control groups. Threonine and methionine supplementation resulted in improved growth performance and nutrient digestibilities, while tryptophan supplementation had little beneficial effect. However, the best feed conversion was found in the control group. Dry. matter and CP digestibilities were improved in the 15LMT and 15LMTT groups. Gross energy, crude fat and phosphorus digestibilities were not affected by the treatment. Among the 15% CP groups, nitrogen digestibility showed the tendency to be increased as the more synthetic amino acids were added. Dry matter and nitrogen excretions were significantly reduced by feeding low protein, amino acid fortified diets, while phosphorus excretion was not influenced. Essential amino acids digestibility was higher in 15LT, 15LMT and 15LMTT groups and lower in the control. The 15LT group showed the best lysine digestibility, and methionine digestibilities were higher in all treated groups than control one. Threonine digestibilities higher in 15LT 15LMT, and 15LMTT than the control. The result shows that threonine and methionine should be added to the diet containing 15% CP diet, fortified with lysine to get same performance of 18% CP diet.

• 한국미생물·생명공학회지
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• 제34권2호
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• pp.94-100
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• 2006

식물생장 촉진 호르몬인 auxin을 생산하는 균주를 선발하기 위해 경산지역 경작지 토양에서 29종의 세균을 분리하였으며 Salkowsky test를 통해 auxin을 생산하는 14종을 선발하였다. 이 중 CAS(chrome azurol S) blue agar에서 siderophore의 생산을 확인 후 auxin과 siderohroe를 동시에 생산하는 AH18을 최종 선발하였다. AH18의 mung-bean adventitious root induction test를 통해 식물생장 촉진 능이 대조구에 비해 1.5배나 뛰어남을 알 수 있었고, 토마토 pot test에서 토마토 시들음병의 윈인균인 F. oxysporum에 대해서 길항력도 나타내었다. 선발된 AHl8 균주는 16S rDNA와 Biolog system을 통해 Bacillus subtilis 동정되었다. B. subtilis AH18은 Sucrose-asparagine-MgsO$_4$(SAM) medium (pH 6.0)에 접종하여 30$^{\circ}C$에서 3일간 배양 시 siderophore를 가장 많이 생산하는 것을 알 수 있었다.

• 한국연초학회지
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• 제36권1호
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• pp.20-25
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• 2014

As part of a balanced testing battery, subchronic inhalation studies on rats are performed to ensure that proposed cigarette modifications do not increase the toxicity of smoke and to demonstrate any instances where a modification may actually contribute to harm reduction. For subchronic inhalation studies with aerosols, the OECD suggests an exposure regimen of 6 hours/day (OECD Guideline 413, 1981), but alternative regimens have also been published: 1 hour/day and $2{\times}1$ hour/day. The aim of this study was to validate a rodent nose-only exposure system for the assessment of inhalation toxicity of cigarette smoke. In this study, cigarette smoke exposure system is consisted of cigarette smoke generator, smoke concentration adjusting system, and 20-port nose-only exposure system. Male SD rats were exposed for 35 days ($2{\times}1$ hour/day) to 3R4F Reference cigarette smoke and analysed major monitoring items of OECD Gudeline 413. WTPM, was measured in the test atmosphere, respiratory function (Buxco Biosystems) during exposure, postexposure urinary exposure biomarkers and alveolar neutrophiles in BAL fluid (Day 35) were evaluated. Validation demonstrated steady WTPM ($257{\pm}20ug/L$, $502{\pm}27ug/L$) and spatial uniformity (<10%). Nose port temperature ($22{\sim}26^{\circ}C$ and RH (45~75%) were acceptable over 35 days. Reductions in respiratory rate and minute volume and increase in the neutrophiles in BALF and the urinary exposure biomarkers were observed cigarette smoke dose dependently. This validation and 35-day inhalation study has shown that the rodent nose-only exposure system may be useful in the inhalation toxicity assessment of cigarette smoke.

• 대한한방내과학회지
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• 제12권2호
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• pp.74-88
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• 1991

In order to study the effects of Goosunsan known clinically for their effects of treatment for cough and asthmas the study was carried out to investigate the effect of Goosunsan extract on the contractile force of the isolated guinea pig's vaviovs kinds smooth muscles and elucidate its mechanism The result were obtained as follows: 1. The isolated trachea & ileum smooth muscles of guinea pig was suspended in the organ bath with oxygenated kreb's Henselsite bicarbonate buffer solution at $37^{\circ}C$, and the developed tension by the drug was recorded with Isometric transducer (nacro F-60). The resting tension was approximately 0.5g. 2. The isolated trachea & ileum smooth muscles of guinea pig was remakably relaxed by the administration of Goosunsan. 3. The contractile response of the trachea smooth muscle of the isolated guinea pig to histamine 10-4 M was remakably by Goosunsan extract. 4. The contractile response of the ileum smooth muscle of the isolated guinea pig to histamine 10-4 M was remakably by Goosunsan extract. 5. The contractile response of the trachea smooth muscle of the isolated guinea pig to acetylcholine 10-4 M was remakably by Goosunsan extract. 6. The contractile response of the ileum smooth muscle of the isolated guinea pig to acetylcholine 10-4 M was remakably by Goosunsan. 7. The contractile response of the trachea smooth muscle of the isolated guinea pig to 5-hydroxytryptamine 10-4 M was remakably by Goosunsan. 8. The contractile response of the ileum smooth muscle of the isolated guinea pig to 5-hydroxytryptamine 10-4 M was remakably by Goosunsan.

• 대한한방내과학회지
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• 제14권1호
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• pp.1-16
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• 1993

This study was carried out to investigate the effect of Oyootang and Shinchulsan extract on the contractile force of the isolated guinea pig trachea smooth muscle and elucidate its mechanism The result were obtained as follow: 1. The isolated trachea smooth muscle was suspended in the organ bath with oxygenated kerb's Henseleit bicarbonate buffer solution at $37^{\circ}C$, and the developed tension by the drug was recorded with isometric tranducer(Nacro F-60). The resting tension was approximately 0.5g 2. The contractile response of the trachea smooth muscle of the isolated guinea pig by histamine $10^{-4}M$ was significantly inhibited by Oyootang and Shinchulsan extract. 3. The contractile response of the trachea smooth muscle of the isolated guinea pig by acetylcholine $10^{-4}M$ was considerably inhibited by Oyootang and Shinchulsan extract. 4. The contractile response of the trachea smooth muscle of the isolated guinea pig by histamine $10^{-4}M$ was significantly inhibited by Oyootanghabshinchulsan extract. 5. The contractile response of the trachea smooth muscle of the isolated guinea pig by acetylcholine $10^{-4}M$ was significantly inhibited by Oyootanghabshinchulsan extract. 6. The contractile response of the trachea smooth muscle of the iso-lated guinea pig by histamine $10^{-4}M$ was significantly inhibited by Oyootang, Shinchulsan and its constituent herbs extract. 7. The contractile response of the trachea smooth muscle of the iso-lated guinea pig by acetylcholine $10^{-4}M$ was significantly inhibited by Oyootang, Shinchulsan and its constituent herbs extract.