• Environmental Mutagens and Carcinogens
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• v.9 no.1
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• pp.1-12
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• 1989

To study the selective organospecific carcinogenesis by the specific chemical carcinogens, the breast cancer induction model by oral administration of 7, 12-dimethylbenzanthracene (DMBA) or by intravenous injection of N-methylni-trosourea (NMU) on female rats was analyzed. In the present experiment, we compared the effexts of ages on the chemical mammary carcinogenesis by studying the metabolic system of the carcinogenic activation, detoxification or DNA damage and repair. The breast tumor incidence was significantly higher in the young rats of 50 days old than in those of one year old rats. As an index of organospecific DNA damage or repair, the in vivo covalent binding index(CBI) of the specific organs by the specific chemical carcinogens was monitored. And for the analysis of carcinogenic activation, the quantity of cytochrome P450`s was determined with the respective type-specific monoclonal antibody, while the detoxication capacity was deduced by the activity monitoring of glutathione S-transferase (GST) and peroxidase. The skin tissues of the mammary region had the highest CBI with both of DMBA and NMU at 50 days of age. And there were contrasting differences in the contents of carcinogenic activation and detoxication system: that is, the content of T.C.D.D.-inducible cytochrome P450 was high, while the activities of GST and peroxidase was low in the mammary skin tissues at tumor prevalent age. These results led us to conclude that the molecular organospecific carcinogenesis, as illustrated with mammary carcinoge-nesis by DMBA and NMU, is operated probably through the differential capacity of the target tissues in the high carcinogenic activation, low detoxication and the low DNA repair function.

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.9
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• pp.1045-1050
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• 2014

$N_2O$(Nitrous Oxide) is known as the third major GHG(Green House Gas) following $CO_2$(Carbon Oxide) and $CH_4$(Methane). The GWP(Global Warming Potential) factor of $N_2O$ is 310 times as large as that of $CO_2$ because $N_2O$ in the atmosphere is very stable, and it becomes a source of secondary contamination after photo-degradation in the stratosphere. Investigation on the cause of the $N_2O$ formation have been continuously reported by several researchers on power sources with continuous combustion form, such as a boiler. However, in the diesel engine, research on $N_2O$ generation which has effected from fuel components has not been conducted. Therefore, in this research, author has investigated about $N_2O$ emission rates which was changed by nitrogen and sulfur concentration in fuel on the diesel engine. The test engine was a 4-stroke direct injection diesel engine with maximum output of 12 kW at 2600rpm, and operating condition of that was set up at a 75% load. Nitrogen and sulfur concentrations in fuel were raised by using six additives : nitrogen additives were Pyridine, Indole, Quinoline, Pyrrol and Propionitrile and sulfur additive was Di-tert-butyl-disulfide. In conclusion, diesel fuels containing nitrogen elements less than 0.5% did not affect $N_2O$ emissions in the all concentrations and kinds of the additive agent in the fuel. However, increasing of the sulfur additive in fuel increased $N_2O$ emission in exhaust gas.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.2
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• pp.217-224
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• 2012

In general, transportation sources include both on-road vehicles and off-road equipment. Off-road vehicles have usually used diesel engines, which have the disadvantage of high NOx emission. Common rail direct injection (CRDI) and after-treatment systems have been applied to meet the exhaust gas emission regulations for diesel vehicles. In the present, agricultural machinery has satisfied the Tier 3 emission regulations by using waste gate turbocharger (WGT) and internal exhaust gas recirculation (EGR). In this paper, the combustion and emission characteristics of an EGR system applied to a 56kW off-road vehicle in non-road transient cycle (NRTC) mode have been investigated. The EGR map was made from foundation experiments determining the EGR duty for all engine operating conditions, and then this map was applied to the NRTC mode. Consequently, the NOx emission was reduced by the EGR system, and the Tier 4 interim emission regulations were satisfied by using both the EGR system and an after-treatment system.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.2
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• pp.178-185
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• 2014

Leonuri Fructus, a semen of Leonuri Herba, has been used for the treatment of menstrual disorders such as amenorrhea, dysmenorrhea and leukorrhea and for the remedy of hyperemia. The present study was conducted to evaluate the anti-inflammatory effects of the Leonuri Fructus extract (Leonurus japonicus Houtt. EtOH extract; LJE) in vivo and in vitro. In vitro study, the MTT assay for cell viability was conducted to determine the non-cytotoxic concentration of LJE treatment in media. The levels of NO were measured with Griess reagent. Pro-inflammatory cytokines were detected by ELISA method. The inflammation-related proteins of this study were detected by immunoblot anlaysis. The increases of NO production and iNOS expression were detected in LPS-treated cells compared with control, but LJE attenuated the increases of NO and iNOS by LPS. LJE reduced the production of TNF-${\alpha}$ and IL-$1{\beta}$ induced by LPS stimulation. LJE suppresses the signaling pathways of NF-${\kappa}B$ and MAPKs in LPS-induced macrophage cells. In vivo study, carrageenan-induced hind paw acute edematous inflammation rat model was used for evaluation of anti-inflammatory activity of LJE. LJE significantly inhibited the increases of hind paw swelling, skin thicknesses and inflammatory cell infiltrations, and decreased the numbers of mast cell induced by carrageenan injection. These results suggest that LJE has an anti-inflammatory therapeutic potential, which is mediated through modulating NF-${\kappa}B$ activation and MAPK phosphorylation. Inhibition of the rat paw edema induced by carrageenan is considered as direct evidence that LJE may be a useful source to treat inflammation.

• Journal of Energy Engineering
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• v.25 no.4
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• pp.159-169
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• 2016

In this study, the effects of MTBE contents as oxygenates in gasoline on exhaust emissions and fuel economy in MPI and GDi vehicles have been investigated. Various oxygen contents have been selected such as 0, 1.0, 2.3 and 2.7 wt%. FTP-75 and HWFET modes as fuel economy test methods which are widely used in Republic of Korea and US were applied to investigate exhaust emissions from the test vehicles. Emissions of CO, NMHC and NOx did not show significant correlation with oxygen contents in gasoline fuels, although having slight difference with these contents. In addition, CO2 emissions were not significantly changed with respect to oxygen content. But in case of warm-up and FTP-75 and HWFET modes including high speed regimes, CO2 emissions showed inverse correlation with oxygen contents. Particulate number concentration was inversely proportional to the oxygen contents, having the minimum value at the condition of 2.3 wt%. In case of fuel economy through carbon balance method, the highest value has been obtained at 2.3 wt% and there was positive correlation with oxygen contents and fuel economy.

• The Korea Journal of Herbology
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• v.23 no.4
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• pp.135-147
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• 2008

Objectives: Oriental pear was used as traditional remedies for respiratory diseases like cough and asthma etc. The purpose of this study was to observe the effects of preventing asthma by the combination of phenolic compound extracted from pear and herbal drugs. Methods: In order to study the effects of preventing asthma by the combination of phenolic compound extracted from pear and herbal drugs(Platycodon grandiflorum, Prunus armeniaca) on allergic asthma, mice were pre-treated by oral administration of the solution before antigen sensitization for 10 days and 20days. And 2 days later, mice were actively sensitized with a subcutaneous injection of ovalbumin and 13 days later, they were provoked with ovalbumin aerosols. The experimental groups were divided 6groups(10d1P, 10d2P, 10d4P, 20d1P, 20d2P and 20d4P) by meditation quantity and period. We measured isometric contractile responses to acetylcholine(ACh) and KCl in the isolated tracheal smooth muscle(TSM), IL-4, eosinophil and lymphocyte in bronchoalveolar lavage fluid(BALF), IgE in serum, WBC, RBC and hemoglobin in blood. Results: Contractile responses of TSM to ACh, the sensitivity of TSM to Ach and the maximal contractile response of TSM to KCl were decreased by direct proportion of meditation quantity. Eosinophil and IL-4 level in BALF were more significantly decreased, and IgE level in serum was more significantly increased in 10d4P and 20d4P group than the control group. Conclusions: Based on the above results, it is assumed that oral administration of the combination of phenolic compound extracted from pear and herbal drugs(Platycodon grandiflorum, Prunus armeniaca) can help the preventing effects of allergic asthma.

• Journal of Microbiology and Biotechnology
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• v.28 no.7
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• pp.1199-1208
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• 2018

Osteoarthritis is a disease that affects the articular cartilage and osseous tissue, and can be worsened by aging, overweight status, and post-traumatic arthritis. The present study aimed to evaluate the effect of ID-CBT5101 (tyndallized Clostridium butyricum) on bone metabolism and the inflammatory response in a monosodium iodoacetate-induced rat model of osteoarthritis. ID-CBT5101 was administered orally at doses of $10^8$ or $10^{10}CFU/day$ for 2 weeks before direct injection of monosodium iodoacetate ($3mg/50{\mu}l$ of 0.9% saline) into the intra-articular space of the rats' right knees. The rats subsequently received the same doses of oral ID-CBT5101 for another 4 weeks. We evaluated the treatment effects based on serum biomarkers, mRNA expression, morphological and histopathological analyses of the knee joints, and weight-bearing distribution analysis. Compared with those in control rats, the ID-CBT5101 treatments significantly reduced the serum concentration of inflammation and bone metabolism markers (i.e., COX-2, IL-6, $LTB_4$, and COMP), and significantly increased the concentration of $IFN-{\gamma}$ and glycosaminoglycans. In addition, the ID-CBT5101 treatments inhibited the mRNA expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases (i.e., MMP-2, MMP-3, MMP-9, MMP-13, TIMP-1, and TIMP-2). Furthermore, the ID-CBT5101 treatments effectively preserved the knee cartilage and synovial membrane, and significantly decreased the amount of fibrous tissue. Moreover, compared with that of the negative control group, the ID-CBT5101 treatments increased the weight-bearing distribution by ${\geq}20%$. The results indicate that ID-CBT5101 prevented and alleviated osteoarthritis symptoms. Thus, ID-CBT5101 may be a novel therapeutic option for the management of osteoarthritis.

• Journal of Embryo Transfer
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• v.18 no.2
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• pp.151-156
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• 2003

The objective of this study was to investigate response of corpus luteum, recovery rate of embryos and production of transferable embryos according to superovulation by PEG 30% FSH in Hanwoo. Cows were selected as recipient, subsequent were superovulated with a total of 400 mg NIH-FSH-P1(Folltropin-V, Canada) given by one shot subcutaneously. At the time of five days after Folltropin injection, 25mg of a PGF$_2$a was injected and cows were inseminated 12 and 24h after the onset of estrus. Seven days after insemination, embryos were collected non-surgically and were cryopreserved by direct transfer methods. The results are summarized as follows : 1. Response of corpus luteum following the superovulation in Hanwoo, right ovary were 52.8%(271/513) and left ovary were 47.1%(242/513), respectively (P<0.05). 2. Recovery rate of embryos following the number of corpus luteum were 83.0%(426/513). 3. Mean number of embryos recovered and transferable embryos were 7.74 and 6.43, respectively (P<0.05). 4. In the total number of transferable embryos per flush were collected 6.4 and all saved transferable embryos were 355.

• Journal of the Korean Vacuum Society
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• v.19 no.5
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• pp.377-384
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• 2010

Many routes have been developed for the synthesis of signle-walled carbon nanotubes (SWCNTs). We spun fibers of SWCNTs directly from vertical furnace using a liquid source of carbon and an iron-contained molecule. The solution was prepared by ethanol as a carbon source, in which ferrocene as a catalyst, thiophene were dissolved. It was then injected from the top of the furnace into hot zone with hydrogen as a carrier gas. We successfully synthesized high-quality SWCNTs by adjusting the various experimental conditions, such as concentration of ferrocene, solution injection rate, concentration of thiophene, and hydrogen flow rate. Measurement of Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy were carried out to find the optimized conditions. The synthesized SWCNTs (1.16~1.64 nm) appeared a bundle structure and well-aligned parallel to the direction of furnace. These results also provide an simple way for high-quality SWCNTs mass production and fabricating direct spining SWCNTs fiber. It will allow one-step production of SWCNTs fiber with potentially excellent properties and wide-range applications.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.5
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• pp.775-786
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• 2017

Monitoring sediment flux is crucial especially for maintaining river systems to understand morphological behaviors. Recently, hydroacoustic backscatter (or SNR) as a surrogate to empirically estimate suspended sediment concentration has been increasingly highlighted for more efficient acquisition of sediment dataset, which is difficult throughout direct sediment sampling. However, relevant contemporary researches have focused on wide range solution applicable for large natural rivers where H-ADCPs with relatively low acoustic frequency have been widely utilized to seamlessly measure streamflow discharge. In this regard, this study aimed at investigating hydroacoustical characteristics based on a very recently released H-ADCP (SonTek SL-3000) with high acoustic frequency of 3 MHz in order to capitalize its capacity to be applied for suspended sediment monitoring in laboratory conditions. SL-3000 was tested in a laboratory flume to collect SNR in conjunction with LISST-100X for actual sediment concentration and particle distribution in both sand and silt sediment injection in various amount. Conventional algorithms to correct signal attenuations for water and sediment were carefully tested to validate whether they can be applied for SL-3000. As result of analyzing the SNR-SSC correlation trand, through further study in the future, it is confirmed that SSC can be observed indirectly by using the SNR.