• Korean Journal of Environment and Ecology
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• v.27 no.4
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• pp.487-497
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• 2013

This study was conducted to suggest vegetation management plan for Gugok landscape maintenance and improvement by deducing the vegetation landscape factors inherent in Yongha Gugok and understanding vegetation structure through the investigate of existing vegetation and plant community structure of Yongha valley in Woraksan National Park. There were broad and flat rocks, natural layered stones, clear water, light stones, stream, valleys, waterfalls, Pinus densiflora and Acer pseudosieboldianum as a result of deducing natural factors on poetry. There were P. densiflora and A. pseudosieboldianum appeared as one of main vegetation landscape elements. The actual vegetation analysis results were as followed. The natural vegetation occupied 67.5% and it was classified as P. densiflora community, Quercus variabilis community, Q. variabilis-P. densiflora community, Q. variabilis-Q. serrata community, Q. serrata community, Q. mongolica community, Q. mongolica-P. densiflora community, Deciduous broad-leaved tree community. The artificial vegetation(18.7%) was classified as Q. serrata community-Larix kaempferi community, Q. mongolica- Castanea crenata community, L. kaempferi community, L. kaempferi-C. crenata community, fruticeta, L. kaempferi-Q. mongolica community. The grassland area(2.0%) was classified as Miscanthus sinensis community, Phragmites communis community, and other areas were classified as landscape tree planting area, farm, orchard, residential area. The representative vegetation were P. densiflora community, Q. variabilis-Q. serrata community, L. kaempferi community, Deciduous broad-leaved tree community in Yongha Gugok. The species diversity index of Shannon was 0.6274~0.9908 on the whole. Yongha Gugok, as a symbol of succession on confucianism and reverence for nature, should be preserved natural valley landscape being clean and wijungchuksa at the end of Joseon Dynasty and Japanese Colonial era. In this historical and cultural Gugok, vegetation landscape management plan is needed to landscape maintenance with P. densiflora community, density control with L. kaempferi community. And it is considered when natural disasters and artificial damages happened, P. densiflora-oriented vegetation restoration plan should be applied in order to restore.

• Journal of Bio-Environment Control
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• v.27 no.3
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• pp.191-198
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• 2018

The objective of this study was to determine the effects of combination of air temperature and soil water contents on growth, physiological disorder rate, and yield of garlic. This experiments has been carried out in the typical plastic house (one side open and other side installed ventilation fans) which was maintained gradient air temperature (maximum different value of air temperature : $6^{\circ}C$). The excessive irrigation (EI) set at $0.34m^3/m^3$ soil moisture contents. The significant differences found in the growth parameters of garlics as affected by air temperature and soil moisture conditions. The plant height of garlic with combination of ambient $(A)+6^{\circ}C$ and optimal irrigation (OI; set at $0.22m^3/m^3$ soil moisture contents) treatments represented 47.4 cm/plant, which was the highest among all the tested treatments. The leaf length and width showed the greatest, which were 16.1 and 2.4 cm/plant, respectively, in $A+6^{\circ}C-OI$. The physiological disorder ratio was higher as 12.9% at $A+6^{\circ}C-OI$ and was not occurred at ambient temperature with EI compared with OI treatment. The bulb and clove weight were dramatically decreased at $A+6^{\circ}C$ temperature treatment. The yields were decreased by 51% in OI at $A+6^{\circ}C$ and $A+3^{\circ}C$ temperature treatment. Those results indicated that yields were decreased and ratio of physiological disorders was increased by high temperature treatments.

• Journal of Bio-Environment Control
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• v.29 no.2
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• pp.130-140
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• 2020

This study was conducted in order to closely examine about optimum shading for superior seedling production a container seedling of Tetradium daniellii, which is being increased the demand for a seedling due to being used for alternative energy, ecological restoration and honey plant. The experiment of investigating the optimum shading on T. daniellii was carried out by using plastic container types (350 ml/cavity) for the forestry facility cultivation. The shading level was treated with full sunlight and with 35%, 55%, 75% of the full sunlight. As a result of having surveyed height and root collar diameter growth of a containerized seedling in T. daniellii, a case of the shading experiment showed a noticeably high value was indicated in the full sunlight. It was surveyed that the stronger shading level leads to the lower growth value. Root development was most active in full sunlight. Dry matter production, it was investigated to be the highest in full sunlight. It was surveyed to be the similar tendency to the outcome of height and root collar diameter growth. QI, which is index of showing the quality of a seedling, stood at 0.98 in full sunlight, thereby having been investigated to be the highest. As for the chlorophyll content in a seedling, the highest chlorophyll content was indicated in the 75% shading treatment with the relatively highest shading level. The photosynthetic rate and the water use efficiency were surveyed to be the highest in full sunlight with 8.48 μmolCO₂·m^-2s^-1, 1.40 μmolCO₂·mmolm^-1H₂O, respectively. As a result of surveying the whole experiment, optimum shading level for superior seedling production a container seedling of T. daniellii is determined in full sunlight (0%). It is expected that this will be used as a basic data for mass production.

• Food Science and Preservation
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• v.15 no.3
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• pp.450-455
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• 2008

Previously, we have shown that green tea extract lowers the intestinal absorption of cholesterol, fat, and other fat-soluble compounds. We conducted this study to determine whether green tea extract affects the rate of $^{14}C$-oleic acid esterification into various lipids in the intestinal mucosa of rats. Male Sprague-Dawley ruts were had free access to a nutritionally adequate AIN-93G diet and deionized water. Initially, the rat's mucosal content of total lipids was measured following 1 mL olive oil administration with (green tea group) or without (control group) 100 mg green tea extract powder. At 1 h and 5 h, intestinal segments were extracted for total lipid analysis. Secondly, to measure mucosal esterification rates of lipids, an abdominal incision was made along the midline, and a 10-cm long jejunal segment of the small intestine was ligated in situ. Then, micellar solutions with or without green tea extract were injected into the ligated jejunal segments and incubated for 10 mill. The micellar solution contained $200.0\;{\mu}$ Ci $^{14}C$-oleic acid, $200.1\;{\mu}mol$ unlabelled oleic acid, $66.7\;{\mu}mol$ 2-monooleoylglycerol, $66.7\;{\mu}mol$ palmitoyl-sn-glycero-3-phosphocholine, 2.2 mmol glucose, $50.0\;{\mu}mol$ albumin, and 16.5 mmol Na-taurocholate per L of phosphate buffered saline (pH, 6.3) with or without 8.87 g green tea extract powder. At 10 min, each rat was sacrificed by cervical dislocation under anesthesia and the segment was removed for lipid analysis. Significant differences were observed in mucosal triglyceride content at 1 h and 5 h in ruts given green tea extract. Significant differences in the rate of $^{14}C$-oleic acid esterification into triglycerides and phospholipids fractions were observed between control and green tea groups. However, There were no significant differences in other lipid fractions. These results indicate that the lowered esterification rates of $^{14}C$-oleic acid into triglycerides and phospholipids fractions is attributable to presence of green tea extract. This may be associated with an inhibitory effect of green tea catechin on the mucosal processes of lipids, leading to the inhibition of intestinal absorption of lipids.

• Food Science and Preservation
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• v.24 no.8
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• pp.1103-1112
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• 2017

This study was performed to investigate the effects of different cooking methods (boiling, roasting, stir-frying, and deep-frying) on folate retention in 6 kinds of mushrooms (Beech-, button-, Juda's ear-, oak-, oyster-, and winter-mushrooms) frequently consumed in Korea. In order to assure reliability of analytical data, trienzyme extraction-L casei method was verified and analytical quality control was also evaluated. Folate contents of mushrooms varied by 6.04-64.82 g/100 g depending on the type of mushrooms. and were significantly affected by cooking methods. Depending on cooking methods, folate contents of mushrooms decreased by 22-48%, 2-31%, and 17-56% for Juda's ear-, oak- and oyster-mushrooms, respectively, while 17-90% of folate was increased in Beech mushroom. Overall, the largest weight loss was found in boiled mushrooms, but the lowest one in deep-fried samples. True folate retention rates considering processing factor were less than 100% for all cooked mushrooms except for Beech samples. Overall, folate loss was the largest by boiling with water but the smallest by deep-frying. Both accuracy and precision of trienzyme extraction-L-casei method were excellent based on a recovery close to 100% and coefficient variations less than 3%. Quality control chart of folate analysis (n=26) obtained during the entire study and an international proficiency test (z-score=-0.5) showed that trienzyme extraction-L casei method is reliable enough for production of national folate database.

• The korean journal of orthodontics
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• v.38 no.4
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• pp.275-282
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• 2008

Objective: The purpose of this study was to investigate the effect of using laser for ceramic bracket bonding of porcelain surfaces and to compare it with conventional treatment of porcelain surfaces. Methods: Ninety feldspathic porcelain specimens were divided into 9 groups of 10, with each group having different surface treatments performed. Surface treatment groups were orthophosphoric acid, orthophosphoric acid with silane, hydrofluoric acid, hydrofluoric acid with silane, sandblasted, sandblasted with silane, laser etched, laser etched with silane, and glazed surface served as a control group. In the laser etched groups, the specimens were irradiated with 2-watt superpulse carbon dioxide ($CO_2$) laser for 20 seconds. Ceramic brackets were bonded with light-cure composite resin and all specimens were stored in water at $37^{\circ}C$ for 24 hours. Shear bond strength was determined in megapascals (MPa) by shear test at 1 mm/minute crosshead speed and the failure pattern was assessed. For statistical analysis, one-way ANOVA and tukey test were used. Results: Statistical analysis showed significant differences between the groups. The HFA + S group showed the highest mean shear bond strength ($13.92{\pm}1.94\;MPa$). This was followed by SB + S ($10.16\;{\pm}\;1.27\;MPa$), HFA ($10.09\;{\pm}\;1.07\;MPa$), L + S ($8.25\;{\pm}\;1.24\;MPa$), L ($7.86\;{\pm}\;0.96\;MPa$), OFA + S ($7.22\;{\pm}\;1.09\;MPa$), SB ($3.41\;{\pm}\;0.37\;MPa$), OFA ($2.81\;{\pm}\;0.37\;MPa$), G ($2.46\;{\pm}\;1.36\;MPa$), Bond failure patterns of HFA and silane groups, except L + S, were cohesive modes in porcelain while adhesive failure was observed in the control group and the rest of the groups. Conclusions : A 2-watt superpulse $CO_2$ laser etching of porcelain surfaces can provide a satisfactory result for porcelain surface treatment for ceramic bracket bonding. Laser irradiation may be an alternative conditioning method for the treatment of porcelain surfaces.

• Korean Journal of Environment and Ecology
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• v.27 no.1
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• pp.52-63
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• 2013

Benthic macroinvertebrates were investigated in Yongdam-dam and Hapcheon-dam resions from June to October 2011, Korea. Yongdam-dam and Hapcheon-dam are geographically contiguous, but they are classified as other water system. Experiment site(YE-1, 2, 3; HE-1, 2, 3) which is thought to be affected by dam, control site(YC-1, 2; HC-1, 2) which is thought not to be affected by dam were selected. Species composition, macroinvertebrate communities, composition of the functional feeding groups, habitat orientied groups and community stability were assessed Yongdam-dam and Hapcheon-dam regions. Ten sites were selected for quantitative(Surber sampler $30cm{\times}30cm$) of benthic macroinvertebrates. As a results, a total of 6,369 individuals including 69 species, 33 families, 12 orders, 6 classes and 4 phyla were recognized in Yongdam-dam region. Also, a total of 5,728 individuals including 81 species, 44 families, 13 orders, 5 classes and 4 phyla were recognized in Hapcheon-dam region. Dominance index was 0.27~0.50(mean${\pm}$SD $0.38{\pm}0.09$), diversity index was 2.22~2.97($2.67{\pm}0.29$), evenness index was 0.63~0.76($0.72{\pm}0.06$) and richness index was 4.43~7.06($5.69{\pm}0.99$) in Yongdam-dam region. Dominance index was 0.40~0.81($0.59{\pm}0.18$), diversity index was 1.40~2.39($2.00{\pm}0.43$), evenness index was 0.38~0.68($0.56{\pm}0.13$) and richness index was 4.04~5.80($4.95{\pm}0.70$) in Hapcheon-dam region. In the functional feeding groups, filtering-collectors and gathering-collectors were the highest in the whole sites. In the habitat orientied groups, burrowers, clingers and swimmers were considerably occupied in all sites. As a result of community stability analysis, experiment sites has been identified much as species high resistance and resilience to environmental changes in Yongdam-dam. Control sites has been identified much as species low resistance and resilience to environmental changes in Hapcheon-dam. Species belonging to the Igroup is considered to be important in the river ecosystem stability of large dams downstream areas.

• Journal of Dental Rehabilitation and Applied Science
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• v.27 no.2
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• pp.197-207
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• 2011

The study aimed at examining how different reline resins affect flexural strength and flexural modulus of denture base. A total of 80 specimens ($64{\times}10{\times}3.3$ mm, according to ISO 1567:1999) of heat-polymerized resin, 40 specimens for (Lucitone199(Dentsply Int., NewYork, USA), SR Ivocap(Ivoclar AG, Schaan, Liechtenstein)) respectively, were polymerized according to the manufacturer's instructions and divided into eight groups(n = 10). Control group specimens remained intact. Specimens in the other groups were abraded on both sides to 2 mm thickness, and were relined in 1.3 mm thickness with 3 types of resins (Lucitone199(Dentsply), SR Ivocap(Ivoclar), and Rebase II(Tokuyama Co., Ltd, Tokyo, Japan)). All specimens were preserved in distilled water at $37^{\circ}C$ for 50 hours, and then were subjected to flexural strength testing in a universal testing machine using 3-point loading. A crosshead speed of 5 mm/min was used, and the distance between the supports was 50 mm. Data analyses included one-way analysis of variance(ANOVA) and the Tukey Honestly Significant Difference test (p=.05). Both heat-polymerized resin groups and auto-polymerized resin groups showed statistically low flexural strength and flexural modulus than control groups. Specimens relined with Lucitone 199 showed significantly higher flexural strength and flexural modulus than those relined with SR-Ivocap. Specimens relined with auto-polymerized resin showed significantly lower flexural strength and flexural modulus than those relined with heat-polymerized resin. Relining with heat-polymerized resins showed superior mechanical properties to relining with an auto-polymerized resin. Relining with the same heat-polymerized resin as the denture base does not affect mechanical properties of a denture. Lucitone199 using a compression-mould technique resulted in the highest flexural strength.

• Food Science and Preservation
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• v.15 no.1
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• pp.161-168
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• 2008

The effects tea beverages (TBs) prepared from powdered green tea (Gt), oolong tea (Ot), black tea (Bt), or pure tea (Pt) with lemon, orange, grenadine etc on cadmium toxicity in rats were investigated Sensory evaluations of the TBs are better than those of each water extracted teas. Cadmium (50 ppm) was administered to experimental rats fed a basic diet, or a diet with various TBs (15% w/v), for 5 weeks. Although body weight gains, feed intakes, and fecal weights in all Cd-treated groups were lower than those in the normal control group (NC), feed efficiency ratio, urine volumes, liver weights, and kidney weights did not differ significantly between groups. The serum ALT and AST levels in the Cd-treated control group (Cd-Co) were higher than those in the NC animals. Serum ALT and AST levels in all Cd-treated rats fed TB-supplemented diets were lower than in animals of the Cd-Co group. Tibia and femur weights in Cd-Co animals were lower than those in NC rats. Tibia and femur weights in Cd-treated rats fed TB-supplemented diets were higher than those in Cd-Co animals. There were no between-group differences in tibia lengths; animals in the NC and TB-supplemented diet groups showed femur lengths longer than those of Cd-Co rats. Although the contents of crude ash and cadmium in the femurs of Cd-Co mts was markedly higher than in the femurs of NC animals, the cadmium content in femurs of Cd-Co rats was significantly lower than that in the femurs of NC animals. The changes in mineral levels caused by Cd administration were alleviated by every TB-supplemented diet tested Whereas fecal calcium excretion by Cd-Co animals was significantly higher than that of NC rats, calcium excretion by Cd-treated rats fed TB-supplemented diets was significantly lower than that of Cd-Co animals. Fecal cadmium excretion by all Cd-treated rats fed TB-supplemented diets was significantly higher than that of Cd-Co animals. In conclusion, this study provides experimental evidence that various TBs may regulate cadmium-induced organ toxicity by reducing cadmium accumulation in tissues through the mechanism of increasing the fecal excretion of cadmium.

• Food Science and Preservation
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• v.24 no.1
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• pp.13-20
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• 2017

This study was carried out to investigate the quality characteristics of fried fish paste prepared with different amounts of squeezed Aronia melanocarpa juice. Squeezed Aronia melanocarpa juice (AMJ) was incorporated into fish paste at different levels (containing 2, 7, and 12 g of Aronia melanocarpa juice in 2 AMJ, 7 AMJ, and 12 AMJ, respectively) based on the total weight of water. Sugar contents and total acidity increased with increasing AMJ content. With increasing amounts of AMJ in fried fish paste, L value inside and on the surface decreased, a value increased, and b value inside decreased, whereas b value on the surface increased. pH decreased with increasing levels of AMJ. As the result of textural properties, folding test in all samples showed that AA means good flexibility. The strength, hardness, and chewiness of fried fish paste with AMJ increased while cohesiveness was not significantly different. Total polyphenol contents increased with higher levels of AMJ. DPPH radical scavenging activity was significantly higher than those of the control. In the sensory evaluation, fried fish paste containing 7 AMJ received the highest score than both the control and other samples.