• Journal of the Korean Geographical Society
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• v.42 no.4
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• pp.469-487
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• 2007

Grain-Size Trend Analysis is the methodology to identify net sediment transport pathways, based on the assumption that the movement of sediment from the source to deposit leaves the identifiable spatial pattern of mean, sorting, and skewness of grain size. It can easily be implemented with low cost, so it has great potentials to contribute to geomorphological research, whereas it can also be used inadequately without recognition of its limitations. This research aims to compare three established methods of grain-size trend analysis to search for the adequate way of application, and also suggest the research tasks needed in improving this methodology 1D pathway method can corporate the field experience into analyzing the pathway, provide the useful information of depositional environments through X-distribution, and identify the long-term trend effectively. However, it has disadvantage of the dependence on subjective interpretation, and a relatively coarse temporal scale. Gao-Collins's 2D transport vector method has the objective procedure, has the capability to visualize the transport pattern in 2D format, and to identify the pattern at a finer temporal scale, whereas characteristic distance and semiquantitative filtering are controversial. Le Roux's alternative 2D transport vector method has two improvement of Gao-Collins's in that it expands the empirical rules, considers the gradient of each parameters as well as the order, and has the ability to identify the pattern at a finer temporal scale, while the basic concepts are arbitrary and complicated. The application of grain sire trend analysis requires the selection of adequate method and the design of proper sampling scheme, based on the field knowledge of researcher, the temporal scale of sediment transport pattern targeted, and information needed. Besides, the relationship between the depth of sample and representative temporal scale should be systematically investigated in improving this methodology.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.2
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• pp.210-219
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• 2017

This study aimed to establish an optimal extraction process and high-performance liquid chromatography (HPLC)-photodiode array (PDA) analytical method for determination of marker compounds, dihydrokaempferol (DHK) and 3-O-methylquercetin (3-MeQ), as a part of materials standardization for the development of health functional foods from stems of Opuntia ficus-indica var. saboten (OFS). The quantitative determination method of marker compounds was optimized by HPLC analysis, and the correlation coefficient for the calibration curve showed very good linearity. The HPLC-PDA method was applied successfully to quantification of marker compounds in OFS after validation of the method in terms of linearity, accuracy, and precision. Ethanolic extracts from stems of O. ficus-indica var. saboten (OFSEs) were evaluated by reflux extraction at 70 and $80^{\circ}C$ with 50, 70, and 80% ethanol for 3, 4, 5, and 6 h. Among OFSEs, OFS70E at $80^{\circ}C$ showed the highest contents of DHK and 3-MeQ of $26.42{\pm}0.65$ and $3.88{\pm}0.29mg/OFS100g$, respectively. Furthermore, OFSEs were determined for their antioxidant activities by measuring 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging and lipid peroxidation (LPO) inhibitory activities in rat liver homogenate. OFS70E at $70^{\circ}C$ showed the most potent antioxidant activities with $IC_{50}$ values of $1.19{\pm}0.11$ and $0.89{\pm}0.09mg/mL$ in the DPPH radical scavenging and LPO inhibitory assays, respectively. To identify active components of OFS, various chromatographic separation of OFS70E led to isolation of 11 flavonoids: dihydrokaempferol, dihydroquercetin, 3-O-methylquercetin, quercetin, isorhamnetin 3-O-glucoside, isorhamnetin 3-O-galactoside, narcissin, kaempferol 7-O-glucoside, quercetin 3-O-galactoside, isorhamnetin, and kaempferol 3-O-rutinoside. The results suggest that standardization of DHK in OFSEs using HPLC-PDA analysis would be an acceptable method for the development of health functional foods.

• Korean Journal of Environment and Ecology
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• v.23 no.5
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• pp.471-484
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• 2009

This study was carried out to classify vegetation structure on the deciduous forest at Namdeogyu area in Deogyusan National Park from May 2007 to September 2008 using the gradient analyses and phytosociological method. The vegetation was classified into Quercus mongolica community(Typical subcommunity, Rhododendron sehlippenbaehii-Q. mongolica subcommunity, Carex lanceolata-Q. mongolica subcommunity), Q. Serrata community(Typical subcommunity, Q. variabilis -Q. serrata subcommunity, Carpinus laxiflora - Q. serrata subcommunity), C. laxiflora community, Fraxinus mandshurica community and Corn us controversa community. Ecological characteristics such as species composition, layer structure, vegetation ratio, and the distribution of individual trees by DBH(diameter at breast height) were significantly different among communities. The order of important value of the forest community with DBH 2cm above plants was Q. mongolica(67.8), F. mandshurica(44.8), Q. serrata(27.5), Acer pseudo-sieboldianum(17.0), C. controversa(l5.9), F. sieboldiana(l1.5), R. schlippenbachii(11.0), C. cordata(11.0), Styrax obassia(10.9), Magnolia sieboldii(10.4) and C. laxiflora(9.8). Distribution of DBH of Q. mongolica had a formality distribution, suggesting a continuous domination of these species over the other species for the time being. In contrast, F. mandshurica appeared limited to the valley of the sheet and a higher frequency of young individuals, suggesting a continuous domination of these species the development of a climax forest terrain. Q. serrata had a higher frequency of young individuals and middle individuals, suggesting a continuous domination of these species over the other species for the time being in contrast. This study examined the correlation between each community and the environment according to DCCA ordination. The Q. mongolica community predominated in the highest elevation habitats which had many C.E.C and T-N. F. mandshurica community predominated in the highest elevation habitats which had many Moisture and EX-Cation. The Q. serrata community and C. laxiflora community mainly occurred in the low elevation habitats which had few C.E.C and T-N. The C. controversa community appeared on the park in the middle habitats.

• Investigative Magnetic Resonance Imaging
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• v.17 no.3
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• pp.181-191
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• 2013

Purpose : To evaluate the usefulness of in vivo magnetic resonance (MR) imaging for tracking intravenously injected superparamagnetic iron oxide (SPIO)-labeled human umbilical vein endothelial cells (HUVECs) in an acute renal failure (ARF) rat model. Materials and Methods: HUVECs were labeled with SPIO and poly-L-lysine (PLL) complex. Relaxation rates at 1.5-T MR, cell viability, and labeling stability were assessed. HUVECs were injected into the tail vein of ARF rats (labeled cells in 10 rats, unlabeled cells in 2 rats). Follow-up serial $T2^*$-weighted gradient-echo MR imaging was performed at 1, 3, 5 and 7 days after injection, and the MR findings were compared with histologic findings. Results: There was an average of $98.4{\pm}2.4%$ Prussian blue stain-positive cells after labeling with SPIOPLL complex. Relaxation rates ($R2^*$) of all cultured HUVECs at day 3 and 5 were not markedly decreased compared with that at day 1. The stability of SPIO in HUVECs was maintained during the proliferation of HUVECs in culture media. In the presence of left unilateral renal artery ischemia, $T2^*$-weighted MR imaging performed 1 day after the intravenous injection of labeled HUVECs revealed a significant signal intensity (SI) loss exclusively in the left renal outer medulla regions, but not in the right kidney. The MR imaging findings at days 3, 5 and 7 after intravenous injection of HUVECs showed a SI loss in the outer medulla regions of the ischemically injured kidney, but the SI progressively recovered with time and the right kidney did not have a significant change in SI in the same period. Upon histologic analysis, the SI loss on MR images was correspondent to the presence of Prussian blue stained cells, primarily in the renal outer medulla. Conclusion: MR imaging appears to be useful for in vivo monitoring of intravenously injected SPIO-labeled HUVECs in an ischemically injured rat kidney.

• Korean Journal of Environment and Ecology
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• v.24 no.6
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• pp.708-722
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• 2010

This study was carried out to classify vegetation structure of the Hyangjeokbong in the Deogyusan National Park using the gradient analysis and phytosociological method. The vegetation was classified into Quercus mongolica community(Rhododendron schlippenbachii subcommunity, typical subcommunity), Q. serrata community, Q. variabillis community, Pinus densiflora community, Cornus controversa community, Fraxinus mandshurica community and Taxus cuspidata community. Ecological characteristics such as species composition, layer structure, vegetation ratio, and the distribution of individual trees by DBH(diameter at breast height) were significantly different among communities. The order of important value of the forest community with DBH 2cm above plants was Q. mongolica(81.2), F. mandshurica, Q. serrata, P. densiflora, Acer pseudosieboldianum, Q. variabillis, Rhododendron schlippenbachii, C. controversa, T. cuspidata. Distribution of DBH of Q. mongolica and Q. serrata had suggesting a continuous domination of these species over the other species for the time being. In contrast, F. mandshurica appeared limited to the valley of the sheet and a higher frequency of young individuals, suggesting a continuous domination of these species the development of a climax forest terrain. P. densiflora and T. cuspidata had suggesting a continuous domination of these species over the other species for the time being in maintain. Q. variabilis and C. controversa had a formality distribution, suggesting a continuous domination of these species over the other species for the time being. This study examined the correlation between each community and the environment according to DCCA ordination. The Q. mongolica community and T. cuspidata community predominated in the highest elevation habitats which had few moisture, Ca and in the low pH. The Q. serrata community mainly occurred in the low elevation habitats which had many moisture. P. densiflora community predominated in the middle elevation and south-facing slope habitats which had few moisture, Ca and in the low pH. F. mandshurica community predominated in the low elevation habitats which had many moisture, Ca and pH.

• Tuberculosis and Respiratory Diseases
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• v.39 no.6
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• pp.474-483
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• 1992

Background: Regardless of its causes, acute lung injury is characterized pathophysiologically by increased pulmonary arterial pressure and the protein-rich edema. Many inflammatory mediators are known to be involved in the pathogenesis of acute lung injury, including oxygen free radicals (OFR). But the changes in pulmonary capillary pressure in the OFR-induced acute lung injury is not clear. While the pulmonary edema characterized by the movement of fluid and solutes is dependent on the pressure gradient and the alveolar-capillary permeability, the role of pulmonary capillary pressure in the development of pulmonary edema is also not well understood. Method: Male Sprague-Dawley rats were divided into 5 groups: normal control (n=5), xanthine/xanthine oxidase (X/XO)-treated group (n=7), catalase-pretreated group (n=5), papaverine-pretreated group (n=7), and indomethacin-pretreated group (n=5). In isolated perfused rat lungs, the sequential changes in pulmonary arterial pressure, pulmonary capillary pressure by double occlusion method, and lung weight as a parameter of pulmonary edema were determined. Results: Pulmonary arterial pressure and pulmonary capillary pressure were increased by X/XO. This increase was significantly attenuated by catalase and papaverine, but indomethacin did not prevent the X/XO-induced increase. Lung weight gain was also observed by X/XO perfusion. It was prevented by catalase. Papaverine did not completely block the increase, but significantly delayed the onset. Indomethacin had no effect on the increase in lung weight. Conclusion: These data suggest that increased pulmonary capillary pressure by OFR may aggravate pulmonary edema in the presence of increased alveolar-capillary permeability and this may not be mediated by cyclooxygenase metabolites.

• Journal of Intelligence and Information Systems
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• v.21 no.4
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• pp.111-131
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• 2015

There are only a handful number of research conducted on pattern analysis of corporate distress as compared with research for bankruptcy prediction. The few that exists mainly focus on audited firms because financial data collection is easier for these firms. But in reality, corporate financial distress is a far more common and critical phenomenon for non-audited firms which are mainly comprised of small and medium sized firms. The purpose of this paper is to classify non-audited firms under distress according to their financial ratio using data mining; Self-Organizing Map (SOM). SOM is a type of artificial neural network that is trained using unsupervised learning to produce a lower dimensional discretized representation of the input space of the training samples, called a map. SOM is different from other artificial neural networks as it applies competitive learning as opposed to error-correction learning such as backpropagation with gradient descent, and in the sense that it uses a neighborhood function to preserve the topological properties of the input space. It is one of the popular and successful clustering algorithm. In this study, we classify types of financial distress firms, specially, non-audited firms. In the empirical test, we collect 10 financial ratios of 100 non-audited firms under distress in 2004 for the previous two years (2002 and 2003). Using these financial ratios and the SOM algorithm, five distinct patterns were distinguished. In pattern 1, financial distress was very serious in almost all financial ratios. 12% of the firms are included in these patterns. In pattern 2, financial distress was weak in almost financial ratios. 14% of the firms are included in pattern 2. In pattern 3, growth ratio was the worst among all patterns. It is speculated that the firms of this pattern may be under distress due to severe competition in their industries. Approximately 30% of the firms fell into this group. In pattern 4, the growth ratio was higher than any other pattern but the cash ratio and profitability ratio were not at the level of the growth ratio. It is concluded that the firms of this pattern were under distress in pursuit of expanding their business. About 25% of the firms were in this pattern. Last, pattern 5 encompassed very solvent firms. Perhaps firms of this pattern were distressed due to a bad short-term strategic decision or due to problems with the enterpriser of the firms. Approximately 18% of the firms were under this pattern. This study has the academic and empirical contribution. In the perspectives of the academic contribution, non-audited companies that tend to be easily bankrupt and have the unstructured or easily manipulated financial data are classified by the data mining technology (Self-Organizing Map) rather than big sized audited firms that have the well prepared and reliable financial data. In the perspectives of the empirical one, even though the financial data of the non-audited firms are conducted to analyze, it is useful for find out the first order symptom of financial distress, which makes us to forecast the prediction of bankruptcy of the firms and to manage the early warning and alert signal. These are the academic and empirical contribution of this study. The limitation of this research is to analyze only 100 corporates due to the difficulty of collecting the financial data of the non-audited firms, which make us to be hard to proceed to the analysis by the category or size difference. Also, non-financial qualitative data is crucial for the analysis of bankruptcy. Thus, the non-financial qualitative factor is taken into account for the next study. This study sheds some light on the non-audited small and medium sized firms' distress prediction in the future.

• Investigative Magnetic Resonance Imaging
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• v.17 no.2
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• pp.133-143
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• 2013

Purpose : To evaluate and compare the accuracy of magnetic resonance imaging (MRI) and ultrasound (US) for detection and estimation of invasion depth of colorectal carcinoma (CRC) by correlation with histopathologic findings in vitro, and to find out the best MR pulse sequence for accurate delineation of tumor from surrounding normal tissue. Materials and Methods: Resected specimens of CRC from 45 patients were examined about tumor detectability and invasion depth of US using high frequency (5-17 MHz) linear transducer in a tube filled with normal saline and MRI in a 8-channel quadrate head coil. The institutional review board approved this study and informed consent was waived. MRI with seven pulse sequences of in- and out-of-phases gradient echo T1 weighted images, fast spin echo T2 weighted image and its fat suppression image, fast imaging employing steady-state acquisition (FIESTA) and its fat suppression image, and diffusion weighted image (DWI) were performed. In each case, both imaging findings of MRI and US were evaluated independently for detection and estimation of invasion depth of tumor by consensus of two radiologists and were compared about diagnostic accuracy according to the histopathologic findings as reference standard. Seven MR pulse sequences were evaluated on the point of accurate delineation of tumor from surrounding normal tissue in each specimen. Results: In specimens of CRC, both imaging modalities of MRI (91.1%) and US (86.7%) showed relatively high diagnostic accuracy to detect tumor and evaluate invasion depth of tumor. In early CRC, diagnostic accuracy of US was 87.5% and that of MRI was 75.0%. There was no statistically significant difference between two imaging modalities (p > 0.05). The best pulse sequence among seven MR sequences for accurate delineation of tumor from surrounding normal tissue in each specimen of CRC was fast spin echo T2 weighted image. Conclusion: MRI and US show relatively high diagnostic accuracy to detect tumor and evaluate invasion depth of resected specimen of CRC. The most excellent pulse sequence of MRI for accurate delineation of tumor from surrounding normal tissue in CRC is fast spin echo T2 weighted image.

• Journal of Life Science
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• v.21 no.10
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• pp.1415-1421
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• 2011

The purpose of this study was to identify the effects of an L-arginine supplementation and regular exercise training on NF-${\kappa}B$, TNF-${\alpha}$, iNOS, Cav-1, eNOS and Ang II in the aortas of D-galactose (D-gal) induced aging rats. The male Strague-Dawley rats were treated with a D-galactose aging inducing agent; the D-gal injection (50 mg/kg) was given intraperitoneally for 12 wk. Experimental groups were divided into five groups: (1) Young control group (Y-Con, n=8), (2) Aging control group (A-Con, n=8), (3) Aging exercise group (A-Ex, n=8), (4) Aging exercise group with L-arginine supplementation group (A-Ex+A, n=8), and (5) Aging with L-arginine supplementation group (A-A, n=8). The exercise consisted of running on a treadmill for 60 min/day at 20 m/min for 6 day/wk, at 0% gradient for 12 wk. The L-arginine supplementation was given orally at a dose of 150 mg/kg/day for 12 wk. The findings of this study were as follows: 1. NF-${\kappa}B$, TNF-${\alpha}$, iNOS, Cav-1 and Ang II proteins in the aortas of D-gal induced rats were significantly increased, however, L-arginine supplementation and regular exercise resulted in a significant inhibition in the expression of NF-${\kappa}B$, TNF-${\alpha}$, iNOS, Cav-1 and Ang II proteins. 2. eNOS protein in the aortas of D-gal induced rats was significantly decreased, however, L-arginine supplementation and regular exercise resulted in a significant increase in the expression of eNOS proteins. In conclusion, the findings of the present study reveal that L-arginine supplementation alone or regular exercise alone or in combination with L-arginine supplementation for 12 wk increases anti-inflammatory effects by decreasing NF-${\kappa}B$, TNF-${\alpha}$, and iNOS protein expressions within the aortic tissue. In addition, L-arginine supplementation alone or regular exercise alone or in combination with L-arginine supplementation may prevent endothelial function by up-regulation of eNOS protein in the aortas of D-gal induced aging rats.

• Journal of Life Science
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• v.22 no.4
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• pp.516-523
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• 2012

The purpose of this study was to investigate the effect of exercise and/or L-arginine on abdominal fat, IGF-1 on GH/IGF-1 axis, fibrinogen, and PAI-1 in aged and obese rats. Male Sprague-Dawley rats were treated with a D-galactose aging inducing agent (50 mg/kg) given intraperitoneally for 12 weeks. Thirty-two male Sprague-Dawley rats were treated and divided into four groups: aging-high fat diet group (AG+HF), AG+HF with L-arginine intake group (AG+LA), AG+HF with exercise group (AG+EX), and AG+EX with L-arginine intake group (AG+LA+EX). The experimental rats underwent treadmill training (60 min/day, 6 days/week at 0% gradient) for 12 weeks. L-arginine was given orally (150 mg/kg/day) for 12 weeks. After the experiment, blood was collected from the left ventricle and abdominal fat was extracted. The results showed that GH was significantly increased in AG+EX and AG+AL+EX. IGF-1 was significantly increased in both the AG+AL+EX and AG+EX group ($p$<0.05), while fibrinogen and PAI-1 were not significantly different among the groups. Abdominal fat was significantly decreased in the AG+LA, AG+EX, and AG+LA+EX groups ($p$<0.05) compared with the AG+HF group. In conclusion, this study suggests that exercise alone or L-arginine alone or a combination not only increases the GH and IGF-1 concentration, but also decreases the abdominal fat mass.