• Journal of the Korean earth science society
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• v.30 no.1
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• pp.69-80
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• 2009

We investigate the dependence of star formation rate and Active Galaxy Nuclei (AGN) frequency on the bar properties, especially the bar strength, using SDSS DR6. To better represent the bar strength, we divided the bars into 6 classes according to their length and axial ratios. There seems to be a fairly good correlation between the star formation rate derived from $H{\alpha}$ emission lines and the bar strength, whereas there is no apparent correlation between the AGN activity and the bar strength. We interpret that the former correlation is due to the dependence of bar-driven gas inflow on the strength of bar. The lack of correlation between AGN and bar properties suggests that the accretion of gas onto a supermassive black hole (SMBH) is regulated by the interplay between the bar and SMBH. The frequency of AGN seems to be dependent on the background density but the star formation rate does not. It suggests that star formation is a localized phenomenon that is mostly determined by the gas density in a galaxy, while AGN activity is more closely related to the host property such as mass and luminosity that are thought to be dependent on the environment through the density-luminosity relation.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.1
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• pp.73-79
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• 2004

The objective of the present study was to determine whether ${\beta}$1-4 galacto-oligosaccharides (GOS) and Candida kefyr combined with nitrate as manipulators could suppress rumen methanogenesis without nitrate poisoning in sheep. Four rumen fistulated wethers were allocated to a $4{\times}4$ Latin square design. Nitrate (1.3 g $NaNO_3$ $Kg^{-0.75}$body weight) with and without GOS and Candida kefyr were administered into the rumen through fistula as a single dose 30 min after the morning meal. GOS and Candida kefyr were supplemented by sprinkling onto the feed and through rumen fistula, respectively. The four treatments consisted of saline, nitrate, nitrate plus GOS and nitrate plus GOS plus Candida kefyr. Physiological saline was used as the control treatment. Compared to saline treatment, the administration of nitrate alone resulted in a very marked decrease in rumen methanogenesis and an increase in rumen and plasma nitrite production and blood methaemoglobin formation consequently causing a decline in oxygen consumption, carbon dioxide production and metabolic rate. When compared to nitrate alone, the simultaneous administration of nitrate with GOS decreased nitrite accumulation in rumen and plasma and nitrate-induced methaemoglobin, while retaining low methane production. However, GOS could not fully restore metabolic parameters reduced by nitrate. When compared to the simultaneous administration of nitrate with GOS, the simultaneous administration of nitrate with GOS plus Candida kefyr lowered rumen methanogenesis to a negligible level, but did not decrease rumen and plasma nitrite accumulation as well as blood methaemoglobin formation. Thus, these results suggest that combination of nitrate with GOS may be a potent manipulator to suppress rumen methanogenesis with abating the hazards of nitratenitrite toxicity in ruminants.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.7
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• pp.948-956
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• 2000

The effect of high and low level of feed intakes on nutrient digestibility, nutrient losses through methane, energy and protein utilization by goats fed on alfalfa (Medicago sativa L.) pellets based diets was investigated in this study. Twelve castrated Japanese goats were employed in two subsequent digestion and metabolism trials. The goats were divided into three groups, offered three diets. Diet 1 consisted of 100% alfalfa pellet, Diet 2 was 70% alfalfa pellet and 30% corn, and Diet 3 was 40% alfalfa pellet and 60% corn. The two intake levels were high (1.6 times) and low (0.9 times) the maintenance requirement of total digestible nutrients (TON). Rumen ammonia nitrogen ($NH_3$-N) level of Diet 1 was lower (p<0.001) compared to Diets 2 and 3, but the values were always above the critical level (I50 mg/liter), The pH values of rumen liquor ranged from 6.02 to 7.30. Apparent digestibility of nutrient components did not show differences (p>0.05) between the two intake levels but inclusion of corn significantly altered the nutrient digestibility. Diet 3 had highest (p<0.001) dry matter (DM), organic matter (OM), ether extract (EE) and nitrogen fee extract (NFE) digestibility followed by the Diet 2 and Diet 1. The crude protein (CP) digestibility values among the three diets were in a narrow range (70.1 to 70.8%). Crude fiber (CF) digestibility for Diet 3 was slight higher (p>0.05) than that for other two diets. When alfalfa was replaced by corn, there were highly significant (p<0.001) increases in DM, OM, EE and NFE apparent digestibility and a slight increase in the CF digestibility (p>0.05). There were no differences (p>0.05) in energy losses as methane ($CH_4$) and heat production among the diets but energy loss through urine was higher for the Diet 1. The total energy loss as $CH_4$ and heat production were higher for the high intake level but the energy loss as $CH_4$ per gram DM intake were same (0.305 kcal/g) between the high and low intake level. Retained energy (RE) was higher for Diet 3 and Diet 2. Nitrogen (N) losses through feces and urine were higher (p<0.001) for Diet 1. Consequently, N retention was lower (p>0.05) for Diet 1 and higher in Diets 3 and 2. It is concluded that inclusion of corn with alfalfa increased the metabolizable energy (ME) and RE, and retained N through reducing the energy and N losses. The high level of intake reduced the rate of nutrient losses through feces and urine.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.6
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• pp.812-817
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• 2012

Nitrate can serve as a terminal electron acceptor in place of carbon dioxide and inhibit methane emission in the rumen and nitrate reducing bacteria might help enhance the reduction of nitrate/nitrite, which depends on the type of feed offered to animals. In this study the effects of three levels of sodium nitrate (0, 5, 10 mM) on fermentation of three diets varying in their wheat straw to concentrate ratio (700:300, low concentrate, LC; 500:500, medium concentrate, MC and 300:700, high concentrate, HC diet) were investigated in vitro using buffalo rumen liquor as inoculum. Nitrate reducing bacteria, isolated from the rumen of buffalo were tested as a probiotic to study if it could help in enhancing methane inhibition in vitro. Inclusion of sodium nitrate at 5 or 10 mM reduced (p<0.01) methane production (9.56, 7.93 vs. 21.76 ml/g DM; 12.20, 10.42 vs. 25.76 ml/g DM; 15.49, 12.33 vs. 26.86 ml/g DM) in LC, MC and HC diets, respectively. Inclusion of nitrate at both 5 and 10 mM also reduced (p<0.01) gas production in all the diets, but in vitro true digestibility (IVTD) of feed reduced (p<0.05) only in LC and MC diets. In the medium at 10 mM sodium nitrate level, there was 0.76 to 1.18 mM of residual nitrate and nitrite (p<0.01) also accumulated. In an attempt to eliminate residual nitrate and nitrite in the medium, the nitrate reducing bacteria were isolated from buffalo adapted to nitrate feeding and introduced individually (3 ml containing 1.2 to $2.3{\times}10^6$ cfu/ml) into in vitro incubations containing the MC diet with 10 mM sodium nitrate. Addition of live culture of NRBB 57 resulted in complete removal of nitrate and nitrite from the medium with a further reduction in methane and no effect on IVTD compared to the control treatments containing nitrate with autoclaved cultures or nitrate without any culture. The data revealed that nitrate reducing bacteria can be used as probiotic to prevent the accumulation of nitrite when sodium nitrate is used to reduce in vitro methane emissions.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.8
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• pp.3333-3338
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• 2015

Background: This study was conducted to analyze positron emission tomography (PET) / computed tomography (CT) and magnetic resonance imaging (MRI) performance with oropharyngeal non-Hodgkin's lymphoma (ONHL).Materials and Methods: The complete image data of 30 ONHL cases were analyzed, all patients were performed PET / CT and MRI examination before the treatment, with the time interval of these two inspections not exceeding 14 days. The distribution, morphology, MRI signal characteristics, enhancement feature, standardized uptake value (SUV) max value and lymph node metastasis way of the lesions were analyzed. Results: Among the 30 cases, 23 cases were derived from the B-cell (76.7%), 5 cases were derived from the peripheral T cells (16.7%) and 2 cases were derived from the NK/T cells (6.7%). 19 cases exhibited the palatine tonsil involvement (63.3%). As for the lesion appearance, 10 cases appeared as mass, 8 cases were the diffused type and 12 cases were the mixed type. 25 cases exhibited the SUVmax value of PET / CT primary lesions as 11 or more (83.3%). MRI showed that all patients exhibited various degrees of parapharyngeal side-compressed narrowing, but MRI still exhibited the high-signal fat, and the oropharyngeal mucosa was intact. 25 cases were associated with the neck lymph node metastasis, among who 22 cases had no necrosis in the metastatic lymph nodes, while the rest 3 cases exhibited the central necrosis in the metastatic lymph nodes. Conclusions: PET / CT and MRI have important value in diagnosing and determining the lesion extent of ONHL.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.658-663
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• 2018

Current measuring methods for air quality are based on ground measurement networks and satellite data. New methods of collecting evidence with advanced sensors are needed because current methods have limitations in collecting evidence for the illegal emission of air pollutants at narrow areas or specific sites. This study analyzed the possibility of using an ultraviolet hyperspectral sensor to measure the concentration of nitrogen dioxide and sulfur dioxide. Two types of spectra were used: simulated spectra for gases with various concentrations using a radiative transfer model and observed spectra for each gas for a concentration. To understand the possibility of using a hyperspectral sensor, the differences between the simulated spectra and the observed spectra were analyzed, and the variation of simulated spectra were then analyzed according to the concentration. The results showed good agreement between observed spectra and simulated spectra. In addition, the absorption depth at specific wavelengths in the simulated spectra had a very strong correlation with the gas concentration. The gas concentration could be estimated using the hyperspectral sensor. In the future, validation would be needed to estimate the gas concentration through observations of various concentrations of gases using a hyperspectral sensor.

• Journal of Korean Society of Forest Science
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• v.95 no.4
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• pp.405-414
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• 2006

Korea is expected to be included in the countries of compulsory reduction of greenhouse gas emissions from the 2nd commitment period (2013~2017). For the negotiations in the future, this study was designed to review the tendency of discussions about carbon account in harvested wood products (HWP), which is currently underway around the globe and approach-specific characteristics, and analyze effects on carbon emissions in our country. As a result, most importantly, except the current IPC default approach there is no big difference among the 3 approaches of carbon account in HWP, which were newly suggested on the basis importers because all the HWP circulated at home are accounted for by carbon-stock changes. Under production approach, those HWP produced at home only are evaluated according to carbon-stock changes with the exception of imported HWP. Atmospheric-flow approach is favorable to net wood exporters, because the spot where ultimate decomposition and combustion arising out of the use of HWP occur is regarded as the place of carbon emission. Meanwhile, the estimation of korean carbon-stock change in HWP showed that as of 2004, stock-change approach was 1.567 Tg C, with production approach being 0.581 Tg C and atmospheric-flow approach being -1.425 Tg C, which means stock-change approach is most favorable to Korea as a net wood importer, while atmospheric-flow approach is the least favorable one, in terms of carbon emissions reduction in Korea.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.24
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• pp.10899-10903
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• 2015

Background: In this study, we aimed to investigate the benefits of 18F-deoxyglucose positron emission tomography/computed tomography (FGD-PET/CT) imaging for staging and radiotherapy planning in patients with head and neck cancer undergoing definitive radiotherapy. Materials and Methods: Thirty-seven head and neck cancer patients who had undergone definitive radiotherapy and PET/CT at the Uludag University Medical Faculty Department of Radiation Oncology were investigated in order to determine the role of PET/CT in staging and radiotherapy planning. Results: The median age of this patient group of 32 males and 5 females was 57 years (13-84years). The stage remained the same in 18 cases, decreased in 5 cases and increased in 14 cases with PET/CT imaging. Total gross tumor volume (GTV) determined by CT (GTVCT-Total) was increased in 32 cases (86.5%) when compared to total GTV determined by PET/CT (GTVPET/CT-Total). The GTV of the primary tumor determined by PET/CT (GTVPET/CT) was larger in 3 cases and smaller in 34 cases compared to that determined by CT (GTVCT). The GTV of lymph nodes determined by PET/CT (GTVLNPET/CT) was larger in 20 cases (54%) and smaller in 12 cases (32.5%) when compared to GTV values determined by CT (GTVLNCT). No pathological lymph nodes were observed in the remaining five cases with both CT and PET/CT. Conclusions: We can conclude that PET/CT can significantly affect both pretreatment staging and assessed target tumor volume in patients with head and neck cancer. We therefore recommend examining such cases with PEC/CT before treatment.

• Environmental and Resource Economics Review
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• v.19 no.1
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• pp.81-100
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• 2010

This paper measures the impacts of the Korea-China Free Trade Agreement (FTA) on the emissions of carbon dioxide ($CO_2$) in Korean export industries. The Korean industrial exports were forecasted by employing Bayesian Kalman Filter Vector Auto-Regression (BVAR) model. The emissions of $CO_2$ were then estimated by applying the $CO_2$ emission coeffcients on the conditionally forecasted values of export by industries. Under the conditional scenario of the 50% reduction in current tariff rate through FTA between Korea and China, the total $CO_2$ emissions in Korea were expected to increase by 1.96% compared to the BAU (Non FT A) trend at the end of 2010. Another conditional scenario with no tariff after 2012 was also adopted. In this case, the total $CO_2$ emlssions were estimated to increase by 2.06% compared to the BAU up until the end of 2014. These facts imply that the FTA between Korea and China would not result in the significant increase of $CO_2$ emissions in Korea.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.10
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• pp.1039-1046
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• 2008

The combining process of UV irradiation and H$_2$O$_2$ was used to investigate characteristics of cefaclor decomposition in the aquatic environment. The separate mixing tank was used to minimize the decreasing effective of contact area caused by sampling. Four baffles were installed inside the UV reactor for the complete mixing of the sample and outside of the reactor was wrapped with aluminum foil to protect the emission of photon energy. Production of OH radical was measured using pCBA(p-Chlorobenzoic acid) indirectly and rate constants were withdrawn pseudo-frist order reaction. Optimum condition for the maximum production of OH radical was found to be pH 3, hydrogen peroxide of 5 mmol/L and recirculation rate of 400 mL/min. Pseudo-frist order reaction rate constant was 0.1051 min$^{-1}$. In the optimum condition, cefaclor was completely decomposed within 40 min and rate constant was 0.093 min$^{-1}$. Decomposition by OH radical producted intermediate anions such as chloride, nitrate, sulfite and acetic acid and phenylglycine. After 6 hr most cefaclor was decomposed by UV/H$_2$O$_2$ process and converted to CO$_2$ and H$_2$O, resulting of operation in the decrease of TOC and acetic acid and the disappearance of phenylglycine.