• Journal of Nutrition and Health
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• v.50 no.2
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• pp.133-141
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• 2017

Purpose: The objective of this study was to examine the association of temperature-fluctuation with freshness quality in various foods. Methods: We investigated the effects of storage conditions on antioxidant activities of cherries and romaine lettuce during storage at $0.7{\pm}0.6^{\circ}C$, $1.2{\pm}1.4^{\circ}C$, and $1.6{\pm}2.8^{\circ}C$. Cherries and romaine lettuce were stored for a period of 9 days and 7 days, respectively. We also analyzed the effects of storage conditions on fresh quality of beef and salmon during storage at $-0.3{\pm}0.8^{\circ}C$, $-0.6{\pm}2.3^{\circ}C$, and $-1.5{\pm}4.4^{\circ}C$. Both of them were stored for a period of 14 days. Results: The amount of water loss was highest in beef, and the microbial count was also the highest at $-1.5{\pm}4.4^{\circ}C$. In the case of salmon, there was no difference in water loss according to storage, and TBA value was significantly increased at $-1.5{\pm}4.4^{\circ}C$. Moisture retention was the highest at $0.7{\pm}0.6^{\circ}C$ in both romaine lettuce and cherry samples. The contents of polyphenol and flavonoid were significantly higher in cherries, and content of polyphenols in romaine lettuce was significantly higher at $0.7{\pm}0.6^{\circ}C$ (p < 0.05). DPPH activity decreased in the order of $0.7{\pm}0.6^{\circ}C$ > $1.2{\pm}1.4^{\circ}C$ > $1.6{\pm}2.8^{\circ}C$ over 7 days. Conclusion: The results indicate that temperature-fluctuation may affect qualities of foods stored in a refrigerator.

• Sleep Medicine and Psychophysiology
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• v.20 no.2
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• pp.69-74
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• 2013

Introduction: Although it is well known that medical students are not getting an adequate amount of sleep, there have been only a few studies on the sleep patterns of medical students and the related factors. Therefore, the present study aimed to investigate the medical students' sleep patterns and the related factors. Methods: A questionnaire package was administered to the $1^{st}$ to $4^{th}$ year medical students at one medical school. It consisted of questions asking about their lifestyles as well as Pittsburgh sleep quality index (PSQI), Epworth sleepiness scale (ESS), global assessment of recent stress scale (GASS), the center for epidemiologic studies-depression scale (CES-D), and Moudsley obsessive-compulsive inventory (MOCI). A total of 352 students (206 males and 146 females) responded to the survey and the result was analyzed using the independent t-test, the chi-square test, the paired t-test, Pearson's correlation and ANOVA. p-values of less than 0.05 were considered statistically significant in analyses. Results: The weekend bedtime was significantly delayed (0 : 49 on weekday ; 1 : 34 on weekend ; t=-5.23, p<0.001), the weekend rise time was delayed (6 : 58 on weekday ; 9 : 30 on weekend ; t=-24.48, p<0.001) and the total sleep time was increased on weekends (5 : 36 on weekday ; 7 : 39 on weekend ; t=15.94, p<0.001). The PSQI score of all subjects was 6.43{\pm}2.64. PSQI was positively correlated with ESS (r=0.383, p<0.001), GASS (r=0.326, p<0.001), CES-D (r=0.393, p< 0.001), and MOCI (r=0.247, p<0.001), but not with GPA (r=0.072, p=0.228. The more senior students had lower PSQI, GASS, CES-D, and MOCI score (p<0.05). Conclusion: Medical students were experiencing a lack of sleep during weekdays as they have a later bedtime and earlier rise time, and consequently had more hours of sleep on weekends. Overall, the medical students were experiencing poor sleep quality and sleep deprivation. Poor sleep quality is associated with psychological problems (daytime sleepiness, stress, depression, and obsessive tendency).

• Food Science and Preservation
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• v.20 no.5
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• pp.668-683
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• 2013

In this study, we investigated the contents of total polyphenol (TP), total flavonoid, and absorbance at 475 nm ($OD_{475}$) which may produced in solid-fermented leaf of Smilax china L. by Aspergillus oryzae as a new functional components with reddish brown color, contents of water soluble substance (WSS), electron donating ability (EDA), Hunter $L^*$, $a^*$, $b^*$ values, sensory overall acceptability (OA) and also, the inhibitory activities (XOI and AOI) against partial purified xanthine oxidase (XO) and aldehyde oxidase (AO) from rabbit liver which were well known to relate the gout, and alcoholic liver disease, respectively in order to optimize water extraction using response surface methodology (RSM). All the $R^2$ values of the second-order polymonials ranged from 0.85 to 0.98, except for the EDA (0.69) and the XOI (0.78). However, the activities of the EDA and XOI were relatively high in the lower concentration of the fermented Smilax china L. leaf. The effects on the water extraction were highest in the concentration, among the dependent variables, and showed significant differences at the 1% level in the TP, TF and WSS contents and the $a^*$, $b^*$ and $OD_{475}$ values, but the OA showed significant differences at the 5% level. The optimal values of AOI, which was the most important functionality in the Smilax china L. that was predicted via RSM, were 59.48% at the 2.19% concentration, a $90.02^{\circ}C$ extraction temperature and a 4.03 minute extraction time ($R^2$: 0.93, p<0.007). The ranges of all the dependent variables of the optimal water extraction were 1.6~1.8% for the concentration, $83{\sim}93^{\circ}C$ for the temperature and 3.4~4.4 minutes for the extraction time; and the optimal water extraction conditions were a 1.7% concentration, an $88^{\circ}C$ extraction temperature and a 3.9-min extraction time.

• The Journal of the Petrological Society of Korea
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• v.13 no.4
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• pp.179-190
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• 2004

Precambrian metamorphic rocks of Yeongyang-Uljin area, which is located in the eastern part of Sobaegsan Massif, Korea, are composed of Pyeonghae, Giseong, Wonnam Formations and Hada leuco granite gneisses. These show a zonal distribution of WNW-ESE trend, and are intruded by Mesozoic igneous rocks and are unconformably overlain by Mesozoic sedimentary rocks. This study clarifies the deformation history of Precambrian metamorphic rocks after the formation of gneissosity or schistosity on the basis of the geometric and kinematic features and the forming sequence of multi-deformed rock structures, and suggests that the geological structures of this area experienced at least four phases of deformation i.e. ductile shear deformation, one deformation before that, at least two deformations after that. (1) The first phase of deformation formed regional foliations and WNW-trending isoclinal folds with subhorizontal axes and steep axial planes dipping to the north. (2) The second phase of deformation occurred by dextral ductile shear deformation of top-to-the east movement, forming stretching lineations of E-W trend, S-C mylonitic structure foliations, and Z-shaped asymmetric folds. (3) The third phase deformation formed I-W trending open- or kink-type recumbent folds with subhorizontal axes and gently dipping axial planes. (4) The fourth phase deformation took place under compression of NNW-SSE direction, forming ENE-WSW trending symmetric open upright folds and asymmetric conjugate kink folds with subhorizontal axes, and conjugate faults thrusting to the both NNW and SSE with drag folds related to it. These four phases of deformation are closely connected with the orientation of regional foliation in the Yeongyang-Uljin area. 1st deformation produced regional foliation striking WNW and steeply dipping to the north, 2nd deformation locally change the strike of regional foliation into N-S direction, and 3rd and 4th deformations locally change dip-angle and dip-direction of regional foliation.

• Journal of Life Science
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• v.25 no.6
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• pp.680-685
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• 2015

Previously, cellulase and xylanase producing microorganism, Bacillus subtilis NC1, was isolated from soil. Based on the 16S rRNA gene sequence and API 50 CHL test the strain was identified as Bacillus subtilis, and named as B. subtilis NC1. We cloned and sequenced the genes for cellulase and xylanase. Plus, the deduced amino acid sequences from the genes of cellulase and xylanase were determined and were also identified as glycosyl hydrolases family (GH) 5 and 30, respectively. In this study to optimize the medium parameters for cellulase production by B. subtilis NC1 the RSM (response surface methodology) based on CCD (central composite design) model was performed. Three factors, tryptone, yeast extract, and NaCl, for N or C source were investigated. The cellulase activity was measured with a carboxylmethyl cellulose (CMC) plate and the 3,5-dinitrosalicylic acid (DNS) methods. The coefficient of determination (R²) for the model was 0.960, and the probability value (p=0.0001) of the regression model was highly significant. Based on the RSM, the optimum conditions for cellulase production by B. subtilis NC1 were predicted to be tryptone of 2.5%, yeast extract of 0.5%, and NaCl of 1.0%. Through the model verification, cellulase activity of Bacillus subtilis NC1 increased from 0.5 to 0.62 U/ml (24%) compared to the original medium.

• Sijohaknonchong
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• v.23
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• pp.213-239
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• 2005

Si is a genre which has been steadily loved by Korean, Particularly, 1920's through 1930's, the Revival Movement of Sijo is made by the school of Literary for People, including Choi Namseon, Lee Byeonggi and Lee Eunsang. And Kwon Goohyeon, a member of KAPF, and Han Yongwoon, not belonging to any literary group were interested in Sijo. Kwon Goohyeon, both a member of KAPF and an anarchist has published A Present of Black Room(1927), which is one of the two published in 1920's-1920's saw only two volumes of Sijo works be published: Choi Namseon's 108 Agony(1926) and Kwon's. However, Kwon Goohyeon's work has not been illuminated. compared with Choi Namseon's and the Revival Movement Sijo by the school of Literary for People. It is because Korean literary world has been under the anti-communism ideology since the Liberation of Korea. However, it caused to explore proletarianism Sijo (Joh woon) and proletarianism poetry (Park Yeonghee) that Kwon is a memeber of KAPF and an anarchist. Han Yongwoon, not belonging to any literary group, was very famous as the poet of My Belolved One's Silence(1926), not as a Sijo poet. It means that he s not been illuminated as a Sijo poet. However, his Sijo is enough to contain his various features such as a man of Independence Movement, a Buddhist monk, a lyrical poet and so on. His first Sijo is For Planting Mookoonghwa-Poetry Written in Prison(1922), which has been published four years prior to My Beloved One's. And his affection on Sijo is inferred from the fact that he has constantly published Sijo more than free verse. The aim this thesis is to find out a position of Sijo 1920's through 1930's from a study on Kwon Goohyeon's and Han Yongwoon's Sijo. Sijo, Korean traditional literary genre, was written by most of the poets including not only the school of Literary for People but Kwon Goohyeon and Han Yongwoon 1920's through 1930's. As a result, the writing of Sijo was not a partial movement by the anti-KAPF group, but by a paradigm in 1920's through 1930's.

• Korean Journal of Plant Taxonomy
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• v.33 no.4
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• pp.421-433
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• 2003

To examine the leaf epidermal microstructure, nine species in five genera (Daphne L. - 4 spp., Diarthron Turcz. - 1 sp., Edgewarthia Meisn. - 1 sp., Stellera L. - 1 sp., Wikstroemia Endl. - 2 spp.) of the Korean Thymelaeaceae were investigated by light microscopy (LM) and scanning electron microscopy (SEM). The stomata of stuo야ed taxa were 'hypostomatic type' and the size range of guard cell was $13.8-34.4{\times}8.7-22.9{\mu}m$: the smallest size of stomata was found in Diathran linifolium ($15.9{\pm}2.6{\times}10.0{\pm}1.3{\mu}m$), while the largest one was measured to Daphne adara ($32.8{\pm}1.6{\times}20.7{\pm}1.3{\mu}m$). The stomatal complex was anomocytic in the most studied taxa, except Daphne kiusiana by having combined with anisocytic together. The shapes of epidermal cells are undulate anticlinal wall. The size range of epidermal cell was $20.7-61.0{\mu}m$; the smallest size of epidermal cell was found in Stellera charnaejasme ($26.0{\pm}1.9{\mu}m$), on the other hand the largest one was found in Edgeworthia chrysantha ($53.6{\pm}3.1{\mu}m$). The well-developed flaky epicuticular waxes can be divided three kinds of pattern - (1) smooth in comparison, not entire platelets and scattered, (2) isolated flake-like platelets, mostly paralleled, sparsely, (3) flake-like platelets, flat, membraneous, protruding from the surfaces at varying angles and densely. Two types of trichome are recognized; (1) Type I: uniseriate trichome of striate surface (D. genkwa, Diarthron linifalium, E. chrysantha, W. ganpi and W. trichotama), (2) Type II: multicellular trichome of papillose surface, uncinated 3-4 nodes (Diathron linifolium). Finally, the systematics significance of the leaf micromorphological features in identification and elucidation of Korean Thymelaeaceae, especially between or within the genera including among the species is also briefly discussed.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.3
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• pp.52-63
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• 2009

Recently in Korea, in the case of metropolis, the urban signalized intersections are controlled by traffic information center or ITS center. Cheon-an City also established traffic information center through the 1st.-$\sim$3rd. ITS public construction and has managed this center that includes bus information service, traffic information collection and providing service, parking information service, and traffic responsive control system. In the Cheon-an metropolitan traffic signal operation, traffic signal controllers were grouped by the each main traffic flow axes and performed with coordinated signal timing for the signalized arterials, and also cycle and split changed by realtime traffic demands. Cheon-an urban traffic responsive control system was evaluated by intersection delay and speed, then it was verified that the delay decreased and vehicle speed improved. However, the rural signal control system to connect adjacency town was evaluated to have lower status than urban area due to the unimproved TOD (Time of day) plan. Therefore actuated signal control was examined for substitutive control system in isolated signal intersection. The aim of this article is to compare actuated signal control with TOD mode in the rural intersection of Cheon-an and to fine superiority of these two control mode, with evaluation of vehicle delay by using HCM(2000) method and by micro-simulation CORSlM. The result of field test show that actuated signal control gave better performance in delay comparison than the existing TOD signal control. And simulation outcome verified that non-optimized TOD has higher delay than optimized TOD mode, non-optimal actuated mode, and optimal actuated signal control mode. Particularly, these three modes delays had not different values according to the paired sample t-test. This is because small traffic demands were loaded in each links. This suggested actuated signal control is expected to be more effective than TOD mode in some rural isolated intersections which frequently need to survey for traffic volume.

• Tuberculosis and Respiratory Diseases
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• v.48 no.6
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• pp.944-955
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• 2000

Background : In patients with chronic obstructive pulmonary disease(COPD), several factors have been associated with a poor prognosis. These include old age, low $FEV_1$ low diffusing capacity, high alveolar-arterial oxygen pressure difference, and finally cor pulmonale. This study was done to investigate if the ECG signs suggesting cor pulmonale were independent prognostic factors in patients with COPD. Method : We analyzed ECG, pulmonary function data and arterial blood gas values in 61 patients who were admitted through the emergency department with an acute exacerbation of COPD. The ECG signs reflecting cor pulmonale were right strial overloading(RAO), right bundle branch block, right ventricular hypertrophy and low-voltage QRS. The 61 patients were divided into 2 groups ; group I with no ECG signs(n=36) and group II with one or more ECG signs(n=25) suggesting cor, pulmonale. Results : Poor, prognostic factors by univariate analysis were low $FEV_1$, $FEV_1$ % pred., VC % pred., DLco, DLco % pred., $PaO_2$ and $SaO_2$ high $PaCO_2$ presence of ECG signs reflecting cor pulmonale, presence of mental status change, use of mechanical ventilator, and long term use of glucocorticoid. A multivariate analysis indicated that age(risk ratio=1.13, 95% confidence interval 1.05-1.23), DLco % pred. (risk ratio=0,97. 95% confidence interval 0.94-0.99), $PaO_2$ (risk ratio=0.95, 95% confidence interval 0.90-0.99) and RAO(risk ratio=5.27, 95% confidence interval 1.40-19.85) were independent prognostic factors of survival. There was a significant difference in survival between the patients with and without RAO(p=0.038). The survival rates at 1, 2, and 5 years were 94.5%. 81.4%, and 50.0% in patients without RAO and 82.4%, 70.6%, and 27.5% in patients with RAO, respectively. Conclusion : These results suggest that the presence of ECG signs reflecting cor pulmonale is a predictor of survival and that RAO of these ECG signs is a significant independent predictor of survival in patients with COPD.

• Tuberculosis and Respiratory Diseases
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• v.45 no.4
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• pp.746-753
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• 1998

Background : Cigarette smoking is closely related to both lung cancer and chronic obstructive pulmonary disease. The incidence of lung cancer is higher in patients with obstructive ventilatory impairment than in patients without obstructive ventilatory impairment regardless of smoking. So, obstructive ventilatory impairment is suspected as an independent risk factor of lung cancer. Methods: For the evaluation of the role of obstructive ventilatory impairment as a risk factor of lung cancer, a total of 73 cases comprising 47 cases of malignant and 26 benign solitary pulmonary nodule were analyzed retrospectively. A comparative study of analysis of forced expiratory volume curves and frequencies of obstructive ventilatory impairment were made between cases with malignant and benign nodules. Results: In comparison of vital capacity and parameters derived from forced expiratory volume curve between two groups. VC, FVC and $FEV_1$ were not significantly different. whereas $FEV_1/FVC%$ and FEF 25-75% showed a significant decrease in the cases with malignant nodule. The frequency of obstructive ventilatory impairment determined by pulmonary function test was significantly higher in the cases with malignant nodule(23.4%) than in benign nodule(3.8%). When the risk for lung cancer was examined by the presence or absence of obstructive ventilatory impairment using the logistic regression analysis, the unadjusted relative risk for the lung cancer of obstructive ventilatory impairment was 17.17. When the effect of smoking and age were considered, the relative risk was to 8.13. Conclusion: These findings suggest that an obstructive ventilatory impairment is a risk factor of lung cancer.