• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.4
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• pp.493-503
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• 2019

This study is composed of nine treatments [Control : "no neutralizing layer+vegetation layer" 3 cm, Treatment 1 : "no neutralizing layer+vegetation layer" 5 cm, Treatment 2 : "no neutralizing layer+vegetation layer" 7 cm, Treatment 3 :"neutralizing layer (cement 3 %)+ vegetation layer (cement 1 %)" 3 cm, Treatment 4 : "neutralizing layer (cement 3 %)+vegetation layer (cement 1 %)" 5 cm, Treatment 5 : "neutralizing layer (cement 3 %)+vegetation layer (cement 1 %)" 7 cm, Treatment 6 : "neutralizing layer [$(Ca{\cdot}Mg)CO_3$] +vegetation layer" 3 cm, Treatment 7 : "neutralizing layer [$(Ca{\cdot}Mg)CO_3$]+vegetation layer" 5 cm, Treatment 8 : "neutralizing layer [$(Ca{\cdot}Mg)CO_3$]+vegetation layer" 7 cm] to find out the vegetation effects according to neutralizing layer types of the acid drainage slope. There were no significant differences observed in soil hardness and soil moisture content of neutralizing layer type while highly difference of moisture content was observed according to the neutralizing and vegetation layer thickness. As for soil acidity, strong acid was shown in the control, treatment 1 and treatment 2. Neutralizing effects were outstanding in treatments of 3, 4, 5 (cement treatment group), 6, 7 and 8 (limestone treatment group). Concerning plants growth characteristics, surface coverage rates, number of germinating woody plants, plant height, and plant root status, there were excellent effects observed in the experimental groups mixed with cement (treatments 3, 4 and 5) and limestone (treatments 6, 7 and 8). At the initial stage, however, plant roots were negatively affected in cement layer treatments of 3, 4 and 5. However, no difference was shown in each layer thickness on the acid drainage slope whereas 3~5 cm thickness neutralizing layer was appropriate in consideration of economic feasibility.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.1
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• pp.1-28
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• 2019

This study analyzed the density and mortality rate of Korean fir at 9 sites where individuals of Korean firs were marked into the live and dead trees with coordinates on orthorectified aerial images by digital photogrammetric system. As a result of the analysis, Korean fir in each site showed considerable heterogeneity in density and mortality rate depending on the location within site. This make it possible to assume that death of Korean fir can occur by specific factors that vary depending on the location. Based on the analyzed densities and mortality rates of Korea fir, we investigated the correlation between topographic factors such as altitude, terrain slope, drainage network, solar radiation, aspect and the death of Korean fir. The density of Korean fir increases with altitude, and the mortality rate also increases. A negative correlation is found between the terrain slope and the mortality rate, and the mortality rate is higher in the gentle slope where the drainage network is less developed. In addition, it is recognized that depending on the aspect, the mortality rate varies greatly, and the mean solar radiation is higher in live Korean fir-dominant area than in dead Korean fir-dominant area. Overall, the mortality rate of Korean fir in Mt. Halla area is relatively higher in areas with relatively low terrain slope and low solar radiation. Considering the results of previous studies that the terrain slope has a strong negative correlation with soil moisture and the relationship between solar radiation and evaporation, these results lead us to infer that excess soil moisture is the cause of Korean fir mortality. These inferences are supported by a series of climate change phenomena such as precipitation increase, evaporation decrease, and reduced sunshine duration in the Korean peninsula including Jeju Island, increase in mortality rate along with increased precipitation according to the elevation of Mt. Halla and the vegetation change in the mountain. It is expected that the spatial patterns in the density and mortality rate of Korean fir, which are controlled by topography such as altitude, slope, aspect, solar radiation, drainage network, can be used as spatial variables in future numerical modeling studies on the death or decline of Korean fir. In addition, the method of forest distribution survey using the orthorectified aerial images can be widely used as a numerical monitoring technique in long - term vegetation change research.

• Journal of Korean Society of Forest Science
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• v.108 no.1
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• pp.40-49
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• 2019

Coarse woody debris (CWD), which is a component of the forest ecosystem, plays a major role in forest energy flow and nutrient cycling. In particular, CWD isolates carbon for a long time and is important in terms of slowing the rate of carbon released from the forest to the atmosphere. Therefore, this study measured the physiochemical characteristics and respiration rate ($R_{CWD}$) of CWD for Larix kaempferi and Pinus rigida in temperate forests in central Korea. In summer 2018, CWD samples from decay class (DC) I to IV were collected in the 14 forest stands. $R_{CWD}$ and physiochemical characteristics were measured using a closed chamber with a portable carbon dioxide sensor in the laboratory. In both species, as CWD decomposition progressed, the density ($D_{CWD}$) of the CWD decreased while the water content ($WC_{CWD}$) increased. Furthermore, the carbon concentrations did not significantly differ by DC, whereas the nitrogen concentration significantly increased and the C/N ratio decreased. The respiration rate of L. kaempferi CWD increased significantly up to DC IV, but for P. rigida it increased to DC II and then unchanged for DC II-IV. Accordingly, except for carbon concentration, all the measured characteristics showed a significant correlation with $R_{CWD}$. Multiple linear regression showed that $WC_{CWD}$ was the most influential factor on $R_{CWD}$. $WC_{CWD}$ affects $R_{CWD}$ by increasing microbial activity and is closely related to complex environmental factors such as temperature and light conditions. Therefore, it is necessary to study their correlation and estimate the time-series pattern of CWD moisture.

• Journal of Nutrition and Health
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• v.52 no.1
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• pp.73-89
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• 2019

Purpose: This study was conducted to identify the dietary life and nutritional status of Korean elementary school students according to breakfast frequency and to clarify the relationship between breakfast frequency of elementary school students and parental dietary and social environmental factors. Methods: This study used data from the 2013 ~ 2015 Korea National Health and Nutrition Examination Survey (KNHANES VI). The subjects were 1,325 elementary school students aged 6 to 11 years old. Subjects were categorized into two groups: a skipping breakfast group (ate breakfast 0 ~ 4 times per week), eating breakfast group (ate breakfast 5 ~ 7 times per week) by sex and grade (lower grade: 1st ~ 3rd/upper grade: 4 th ~ 6 th). Results: Among upper grade boys and girls, the skipping breakfast group had a higher rate of childhood obesity than the eating breakfast group. In lower grade boys, the mothers of the skipping breakfast group had higher rates of economic activity and eating breakfast alone without family members than the mothers of the eating breakfast group. For lower grade boys and girls and upper grade boys, the skipping breakfast group had a higher rate of parents who did not eat breakfast than the eating breakfast group. The energy intake of the breakfast consumed by all subjects was less than 25% of the Estimated Energy Requirements (EER). Moreover, for upper grade boys and girls, the skipping breakfast group had a higher rate of subjects whose daily intake was below the Estimated Average Requirement (EAR) for iron than the eating breakfast group. Conclusion: Breakfast frequency of elementary school students was related to childhood obesity. The frequency of eating breakfast among elementary school students was related to the dietary life factors of parents such as breakfast frequency and dietary condition. Intake for breakfast was less than 25% of the EER, while the skipping breakfast group had a higher rate of subjects whose daily intake was below the EAR for iron than the eating breakfast group. Therefore, it is necessary to consider diverse forms of policy support such as opening nutrition education programs for parents and practicing morning meals at school for elementary school students to provide regular and balanced breakfasts.

• Journal of Mushroom
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• v.17 no.2
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• pp.52-63
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• 2019

Agrocybe spp. belongs to the Agaricales order, Bolbitiaceae family, and Agrocybe genus. In Korea, so far, it has been cultivated through bottle cultivation; therefore, this study was conducted for the development of a new cultivar using the bag cultivation method for quantitative improvement. Thirty-three gene resources of Agrocybe spp. were collected and their quantity and characteristics of bag cultivation were examined. Next, 5 kinds of crossing parents were selected based on the cultivation period and shape of the fruit body. Seven strains were selected through 3 cross combinations. The 7 selected strains and the comparative cultivar 'Cham' were cultivated in a bag. As a result, the cultivation period was 49 days for 'JBAC15-1' and 50 days for 'JBAC15-6' which are 4 days and 3 days less than the cultivation period of the comparative cultivar 'Cham'(53 days), respectively. Cultivation periods of other strains except for 'JBAC15-1' and 'JBAC15-1' were longer than that of the comparative cultivar'Cham'. The best ratio of primordia formation among the selected strains was found to be that of 'JBAC15-1' with 96.1% followed by 'JBAC15-6' with 94.5%. These rates were 3.1% and 1.5% higher than the ratio of primordia formation of the comparative cultivar 'Cham', which is found to be 93.0%. The quantity was maximum in the 'JBAC15-1' cultivar with 176.8 g per bag followed by 'JBAC15-6' with 168.7 g per bag. The quantities were 10% and 5% more than the comparative cultivar 'Cham' with 160.7 g per bag. Based on these results, 'JBAC15-1' and 'JBAC15-6', which had shorter cultivation periods and more quantities than the comparative cultivar 'Cham' were finally selected. For the selected strains of 'JBAC15-1' and 'JBAC15-6', mycelial growth was observed to be optimal on PDA medium and the optimum temperature was $27.5^{\circ}C$. The optimum pH was pH 5 for 'JBAC15-1' and pH 6 for 'JBAC15-6'. The color of the pileus of the fruit body was dark brown in 'JBAC15-1' and 'Cham' and light brown in 'JBAC15-6'. The pileus was hemispherical in shape in both 'JBAC15-1' and 'Cham'. However, the colors of the stem were different - light brown in 'JBAC15-1', white in 'JBAC15-6', and ivory in the comparative cultivar 'Cham'.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.2
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• pp.191-197
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• 2019

Although auto-adjusting positive airway pressure (APAP) titration at home has several advantages over a CPAP titration in terms of convenience and time saving, there are still concerns as to whether it will show corresponding accuracy when compared to laboratory-based polysomnography (PSG) and CPAP titration. To obtain more evidence supporting home-based auto-titration, APAP titration was performed at home for patients who were presented with OSA on laboratory-based diagnostic PSG followed by CPAP titration. A total of 79 patients were included in the study. They all underwent split-night PSG with CPAP titration, and APAP titration for more than 7 days. The patients with successful titration at both situations were selected. The optimal pressure and apnea-hypopnea index (AHI) of CPAP and APAP titration were compared. The optimal pressure for CPAP and APAP titration were $7.0{\pm}1.8cmH_2O$ and $7.6{\pm}1.6cmH_2O$ (P<0.001), whereas the corresponding AHI were $1.3{\pm}1.5/h$ and $3.0{\pm}1.7/h$ (P<0.001). As a result, the achievement rates of optimal pressure for CPAP and APAP titration were 96.2% and 94.9% (r=-0.045, P=0.688), respectively. The results of this study did not differ with regard to the optimal pressure between CPAP and APAP titration. Overall, CPAP and APAP titrations should be chosen depending on a required situation.

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.145-150
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• 2019

In this study, we used extracts obtained from five different solvents (water, ethanol, hexane, ethyl acetate, butanol) of Achyranthes japonica (AJ) and also AJ fermented with Lactobacillus plantarum (LP) to confirm effects on the anti-inflammatory activity in RAW264.7 cells. Experiments of measuring nitric oxide (NO) and cytokine production were performed in lipopolysaccharide (LPS)-induced RAW264.7 cells, and the expression of both cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) was observed by a western blot method. The cytotoxicity of RAW264.7 was confirmed by the cell counting kit (CCK) assay at a concentration of $100{\mu}g/mL$, which has no toxicity. As a result of the inhibition of NO production, the inhibition rate of AJ-LP extracted with ethanol samples was about 74% higher than that of using the control group. Interleukin-6 (IL-6), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), and Interleukin-$1{\beta}$ (IL-$1{\beta}$), which are inflammatory cytokines, also showed an excellent efficacy with inhibition rates of about 57, 70, and 74%, respectively. Comparing to the results of COX-2 and iNOS expression in the AJ group, the inhibition rate of 20-hydroxyecdysone was the highest than others. On the other hand, the COX-2 expression level of AJ-LP group decreased about 16% compared to that of the control group, and the iNOS expression level was also decreased about 7%. These results suggest that the extract of AJ fermented from L. plantarum can be used as an anti-inflammatory natural material.

• Journal of Food Hygiene and Safety
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• v.34 no.2
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• pp.183-190
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• 2019

Ursolic acid is recognized for various effects such as anti-cancer, antioxidant, and anti-inflammatory activity. In this study, we confirmed the anti-cancer effect of ursolic acid on human melanoma cancer cells, A375SM and A375P. Survival rate of the melanoma cells was confirmed by MTT assay and the proliferation rate was confirmed by wound healing assay. The rate of apoptotic bodies was confirmed by DAPI staining, and apoptosis rate was confirmed by flow cytometry. The induction of apoptosis protein was examined by western blotting according to the concentration of ursolic acid in melanoma cells. The survival and proliferation rates of melanoma cells were decreased according to the treatment concentrations of ursolic acid. DAPI staining showed that chromosomal condensation of melanoma cells was increased with increasing concentrations of ursolic acid, and increased apoptosis rate of melanoma cells by ursolic acid was confirmed by flow cytometry. We also confirmed by western blotting that cleaved-PARP and Bax were increased and Bcl-2 was decreased at $12{\mu}M$ concentration of uricolic acid in melanoma cells. This study was carried out at low concentrations of ursolic acid, 0 to $20{\mu}M$, and analyzed 24 h after treatment. As a result of this study, it is thought that ursolic acid has the anti-cancer effect through the regulation of apoptosis-related proteins in melanoma cells A375SM and A375P.

• Korean Journal of Plant Resources
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• v.32 no.2
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• pp.116-123
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• 2019

Angelica gigas Nakai (AGN) is a traditional medicinal herb especially in Korea. It contains pyranocoumarins, which are major active components including decursin (D) and decursinol angelate (DA). This study was carried out to determine the change in active component content and antioxidant activity depending on the root diameter of AGN. Several processing steps are involved to use AGN roots as medicine. The dried AGN roots are divided into body (B), thick root (TkR), medium root (MR) and thin root (TnR) according to their diameter before cutting into medicine. The recovery rates of each root parts per 100 kg were measured as $32.3{\pm}2.5$, $9.0{\pm}1.0$, $39.3{\pm}2.1$ and $15.0{\pm}1.0%$, respectively and the mean diameters were measured as $51.95{\pm}4.55$, $7.05{\pm}0.89$, $2.88{\pm}0.49$ and $1.57{\pm}0.32mm$. Two index components, D and DA, were analyzed. The change of both D and DA content showed a similar tendency. Both D and DA content were increased as the root diameter decreased (higher in TnR). In addition, antioxidant activity was higher in B and TnR, and lower in TkR and MR than control. This study showed that the thinner the root diameter, the higher the D and DA content in AGN roots and that TnR has excellent antioxidant activity compared to other root parts, suggesting that the thinner root part of AGN could be used as a potential material.

• Pediatric Infection and Vaccine
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• v.26 no.1
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• pp.11-21
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• 2019

Purpose: We aimed to investigate the epidemiological characteristics of Staphylococcus aureus bacteremia in Korean children. Methods: We retrospectively collected and analyzed data from the medical records of the patients with S. aureus bacteremia ${\leq}18years$ of age in Gil Medical Center from 2002 to 2016. Results: A total of 212 SAB cases were detected. The annual incidence of SAB from 2002 to 2016 ranged from 0.77 to 1.95 per 1,000 patients hospitalized. The neonate group (<28 days of age) and the pediatric group (28-18 years of age) were 51.4% (n=109) and 48.6% (n=103), respectively. According to the origin of infection, there were 93 cases (43.9%) of community-associated (CA)-SAB and 119 cases (56.1%) of healthcare-associated (HA)-SAB. The rates of HA-SAB among the neonate group and among the pediatric group were 64.2% and 47.6%, respectively (P=0.015). There was no difference in complications between CA-SAB and HA-SAB, but mortality was higher in HA-SAB. The proportion of methicillin-resistance S. aureus (MRSA) was the highest in neonates (88.1%), decreased with age, and was 36.4%-37.5% among children aged ${\geq}5years$. The MRSA proportion was 72.2%, showing no consistent trend over the period. Conclusions: The annual incidence of SAB and the proportion of MRSA in SAB remained constant in the recent 15 years in children. Judicious decision of antimicrobial agents for treatment considering the patient's age and the origin of infection is necessary.