• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.21-22
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• 2019

Melanin is a mixture of pigmented biopolymers synthesized by epidermal melanocytes that determine the skin, eye, and hair colors. Melanocytes produce two different kinds of melanin, eumelanin (dark brown/black insoluble pigments found in dark skin and dark hair and pheomelanin (lighter red/yellow). The biological role of melanin is to prevent skin damage by ultraviolet (UV) radiation. However, the overproduction or deficiency of melanin synthesis could lead to serious dermatological problems, which include melasma, melanoderma, lentigo, and vitiligo. Therefore, regulating melanin production is important to prevent the pigmentation disorders. Myanmar has a rich in natural resources. However, the chemical constituents of these natural resources in Myanmar have not been fully investigated. In the effort to search for compounds with anti-melanin deposition activity from Myanmar natural resources, five plants were collected in Myanmar. Extracts of these collected five plants were tested for anti-melanin deposition activity against a mouse melanoma cell line (B16-F10) induced with ${\alpha}$-melanocyte-stimulating hormone (${\alpha}$-MSH) and 3-isobutyl-1-methylxanthine (IBMX), and their anti-melanin deposition activities were compared with the positive control, arbutin. Among the tested extracts, the CHCl3 extracts of the Premna serratifolia (syn: P. integrifolia) wood showed anti-melanin deposition activities with IC50 values of $81.3{\mu}g/mL$. Hence, this study aims to identify secondary metabolites with anti-melanin deposition activity from P. serratifolia wood of Myanmar. P. serratifolia belongs to the Verbenaceae family and is widely distributed in near western sea coast from South Asia to South East Asia, which include India, Malaysia, Vietnam, Cambodia, and Sri Lanka. People in Tanintharyi region located in the southern part of Myanmar utilize the P. serratifolia, Sperethusa crenulata, Naringi crenulata, and Limonia acidissima as Thanaka, traditional cosmetics in Myanmar. Thanaka is applied in the form of paste onto skins to make it smooth and clear, as well as to prevent wrinkles, skin aging, excessive facial oil, pimples, blackheads, and whiteheads. However, the chemical constituents responsible for their cosmetic properties are yet to be identified. Moreover, the chemical constituents of P. serratifolia was almost uncharacterized. Investigation of the P. serratifolia chemical constituents is thus an attractive endeavor to discover new anti-melanin deposition active compounds. The investigation of the chemical constituents of the active CHCl3 extract of P. serratifolia led to isolation of four new lignoids, premnan A (1), premnan B (2), taungtangyiol C (3), and 7,9-dihydroxydolichanthin B (4), together with premnan C (5) (assumed to be an artifact), one natural newlignoid,(3R,4S)-4-(1,3-benzodioxol-5-ylcarbonyl)-3-[(R)-1-(1,3-benzo dioxol-5-yl)-1-hydroxy methyl]tetrahydro-2-furanone (6), and five known compounds (7-11)1,2). The structures of all isolated compounds were determined on the basis of their spectroscopic data and by comparison with the reported literatures. The absolute configurations of 1-3 and 5 were also determined by optical rotation and circular dichroism (CD) data analyses1). The anti-melanin deposition activities of all the isolated compounds were evaluated against B16-F10 cell line. 7,9-Dihydroxydolichanthin B (4) and ($2{\alpha},3{\alpha}$)-olean-12-en-28-oic acid (11) showed strong anti-melanin deposition activities with IC50 values of 18.4 and $11.2{\mu}M$, respectively, without cytotoxicity2). On the other hand, compounds 1-3, 5, and 7 showed melanogenesis enhancing activities1). To better understand their anti-melanin deposition mechanism, the effects of 4 and 11 on tyrosinase activities were investigated. The assay indicated that compounds 4 and 11 did not inhibit tyrosinase. Furthermore, we also examined the mRNA expression of microphthalmia-associated transcription factor (MITF), tyrosinase (TYR), tyrosinase-related protein-1 (TRP-1), and tyrosinase-related protein-2 (TRP-2). Compounds 4 and 11 down-regulated the expression of Tyr and Mitf mRNAs, respectively. Although the P. serratifolia wood has been used as traditional cosmetics in Myanmar for centuries, there are no scientific evidences to support its effectiveness as cosmetics. Investigation of the anti-melanin deposition activity of the chemical constituents of P. serratifolia thus provided insight into the effectiveness of the P. serratifolia wood as a cosmetic agent.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.4
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• pp.282-293
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• 2018

The heading response of rice varieties is determined by the combined effects of their basic vegetative phase (BVP), photoperiod-sensitivity (PS), and thermo-sensitivity (TS). This study was performed to analyze the effect of differences among heading ecotypes of rice on their heading response in the field. To do this, we investigated the heading response of 15 varieties grown under different day-length and temperature conditions in a phytotron. The characteristics of heading ecotypes were compared to the heading responses in the field-grown rice varieties that were used in the phytotron experiments. The ranges of these characteristics across the 15 varieties were 18 - 35 days for BVP, 12 - 61 days for PS, and 12 - 35 days for TS. In comparisons of coupled varieties that differed only in a single trait among BVP, PS, and TS, the variety with the longer BVP and that with the higher PS had a longer period from sowing to heading (DTH), while the variety with the higher TS had a shorter DTH. The comparative magnitude of DTH in the coupled varieties followed the PS trait when BVP and PS were involved, the BVP trait when BVP and TS were involved, and the PS trait when PS and TS were involved in the heading response of field-grown rice. When comparing the coupled varieties with different traits of the three examined factors, the heading response was consistent with the PS trait. The DTH in all 15 varieties was significantly correlated with the PS, and the DTH in 9 selected varieties with a relatively small PS was correlated with BVP. The reduced DTH of rice in the July 10 seeding treatment compared to those in the June 25 and May 11 seeding treatments was positively associated with PS, but not with TS. We concluded that the heading response of rice varieties under natural conditions in Korea is mainly governed by the PS trait and is also greatly affected by the BVP trait when the PS is small.

• Journal of Climate Change Research
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• v.1 no.2
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• pp.133-145
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• 2010

This study examined the characteristics of tropical cyclone(TC) activity over the western North Pacific(WNP) in 2009. Twenty-two TCs formed in 2009, which is slightly below normal(1979~2009 average: 25.8) and most of these occurred during the months of July to October. Most TCs in 2009 was formed over the northern Philippines and the eastern part of the WNP and they moved towards the South China Sea and the east of Japan, resulting in less TC affecting the East China Sea and Korea. The TC activity in 2009 is modulated by the large-scale circulations induced by the El $Ni{\tilde{n}}o$ and vigorous convection activity over the WNP. As the general characteristics of El $Ni{\tilde{n}}o$ year, the difference in sea surface temperature between the central Pacific and the eastern Pacific causes an anomalous westerly winds, expanding the WNP monsoon trough farther eastward. Accordingly, TC formation has relatively increased in the east part of the WNP. Active convection activities over the subtropical western Pacific excite a Rossby wave propagating from the South China Sea to mid-latitudes, resulting in an anomalous easterly steering flow in the South China, anomalous northwesterly over the East China Sea and Korea, and anomalous southwesterly over the east of Japan. Summing up, the TCs cannot enter the East China Sea and Korean region and instead they move towards the South China Sea or south-east of Japan. There were no effects of TCs in Korea in 2009. It is anticipated that this study which analyzed unusual TC activity and large-scale circulations in 2009 would help the predictability of TC effects to increase according to climate change in the East Asia.

• Korean Journal of Occupational Therapy
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• v.26 no.4
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• pp.57-72
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• 2018

Objective : This study aims to identify the self-reported driving abilities of elderly drivers and their correlations to the demographic factors that influence them, and to verify the adequacy of the hypothetical model, constructed based on vision, auditory, cognition, motor, and psychological factors, in order to present a path model on the self-reported driving abilities of elderly drivers. Methods : The participants in this study were 122 elderly drivers aged 65 years or older residing in the community. This study evaluated the following factors of the participants: Vision and hearing, motor ability, cognitive ability, depression, self-reported driving abilities. Results : The results of this study are as follows. In the case of men, the self-reported driving ability score was higher than for women, and those driving 6-7 days per week had higher scores than those driving 3 days or less. The period of holding a driver's license and driving experience positively correlated with self-reported driving abilities. The final model of factors influencing the self-reported driving abilities of elderly drivers had a p value (.911) exceeding .05; TLI (1.202), NFI (.949), and CFI (1.000) of over .90; and RMSEA (.000) of lower than 0.1, indicating that the hypothesis model fit the data well. First, the directly influential factors on the self-reported driving abilities of elderly drivers were depression, decreased hearing, and grip strength. Second, age was found to have a direct influence on depression and grip strength; moreover, depression and grip strength as a mediator indirectly influenced their self-reported driving abilities. Third, depression was found to have a direct influence on their delayed cognitive processing and grip strength. Conclusion : The significance of this study is in the identification of direct and indirect factors influencing the self-reported driving abilities of elderly drivers in regional communities, and in the verification of multi-dimensional effects of diverse factors influencing such abilities.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.4
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• pp.331-336
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• 2018

The aim of the present study was to identify the metabolic changes that have occurred in Hanwoo Native Cow. Analysis of serum metabolites was carried out to investigate relationship of pregnancy rate and feeding systems. Totally, 281 cows were used for grazing and barn feeding. Grazing was carried out for 5 months in the pasture. In barn feeding, concentrate 3.0 Kg(TDN 68%, CP 14%) and rice straw 6 kg(TDN 50%, CP 6.5%) were fed. Artificial insemination(AI) carried out by timed AI procedure. The level of glucose(mg/dl), cholesterol(mg/mL), BUN(mg/dl), AST(U/l), ALT(U/l), and NEFA(uEq/l) were analyzed. In Table 1, barn feeding with 120% group was showed high Cholesterol and BUN levels compared those with 80% feeding group(p<0.05). In Table 2, 60 pregnant cows in grazing herd showed low Cholesterol, AST and NEFA levels compared to 43 non-pregnant cows($149.8{\pm}4.9$, $99.1{\pm}2.6$, $326.7{\pm}15.7$ vs. $165.9{\pm}4.6$, $108.9{\pm}3.2$, $419.2{\pm}32.8$, respectively, p<0.05). In Table 3, 126 grazing feeding cows showed high Glucose, Cholesterol, AST, ALT, and NEFA levels compared to 22 barn feeding cows($84.8{\pm}1.3$, $142.5{\pm}2.5$, $97.7{\pm}2.3$, $34.3{\pm}0.5$, $317.8{\pm}13.6$ vs. $56.0{\pm}1.3$, $128.9{\pm}4.6$, $80.9{\pm}2.0$, $27.1{\pm}0.9$, $160.2{\pm}18.9$, respectively, p<0.05). Further study needed to obtain more accurate level of metabolites in serum for pregnant and non-pregnant cows.

• 대한공업교육학회지
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• v.44 no.1
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• pp.94-113
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• 2019

This study has been performed for the purpose of providing the basic pedagogical resources to the specialized and meister high school related educational settings in either constructing educational contents suitable for the students'technological thinking disposition or fortifying the disposition required for the students.. A tool of secured validity and reliability has been used to test technological thinking disposition for the specialized and Meister high school students. Followings are the major results of the survey analysis for the subjects. 1. Technological thinking disposition with the most component ratio for the specialized & meister high school was turned out to be Technological Operating Disposition(TOD). The second most was Technological Planning and Reflecting Disposition(TPRD). Technological Curiosity Disposition(TCD), Technological Problem Identifying and Resolving Disposition (TPIRD), Technological Analyzing Disposition(TAD), Technological Creativity and Expressing Disposition(TCED) were in sequence. 2. In comparing the technological disposition of specialized high school students with that of meister high school students, the statistical test showed no evidence for the difference between the two group. 3. Statistical comparison test for the gender difference in technological thinking disposition has also been performed for the students of specialized and meister high school. The result showed that the magnitude of difference between the component ratio of TCD and TPIRD for the boy students was bigger than that for the girl students. In the TPRD, the component ratio for the disposition of the girl students was bigger than that of the boy students on the other hand. 4. For the comparison test of the technological thinking disposition between boys and girls only for the specialized high school students, the results showed the same different component ratio results as the results of the test for the specialized and meister high school students. 5. For the gender difference of meister high school student for the technological thinking disposition, there was no statistical evidence supporting the difference.

• Korean Journal of Environmental Agriculture
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• v.37 no.3
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• pp.189-196
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• 2018

BACKGROUND: Water quality management of river requires quantification of pollutant loads and implementation of measures through monitoring study, but it requires labour and costs. Therefore, many researchers are performing nonpoint source pollution analysis using computer models. However, calibration of model parameters needs observed data. Nitrogen concentration in rainfall is one of the factors to be considered when estimating the pollutant loads through application of the nonpoint source pollution model, but the default value provided by the model is used when there are no observed data. Therefore, this study aims to provide the representative nitrogen concentration of the rainfall for the administrative district ensuring rational modeling and reliable results. METHODS AND RESULTS: In this study, rainfall monitoring data from June 2015 to December 2017 were used to determine the nitrogen concentration in rainfall for each administrative district. Range of the $NO_3{^-}$ and $NH_4{^+}$ concentrations were 0.41~6.05 mg/L, 0.39~2.27 mg/L, respectively, and T-N concentration was 0.80~7.71 mg/L. Furthermore, the national average of T-N concentration in this study was $2.84{\pm}1.42mg/L$, which was similar to the national average of T-N 3.03 mg/L presented by the Ministry of Environment in 2015. Therefore, the nitrogen concentrations suggested in this study can be considered to be resonable values. CONCLUSION: The nitrogen concentrations estimated in this study showed regional differences. Therefore, when estimating the pollutant loads through application of the nonpoint source pollution model, resonable parameter estimation of nitrogen concentration in rainfall is possible by reflecting the regional characteristics.

• Korean Journal of Environmental Agriculture
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• v.37 no.4
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• pp.235-242
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• 2018

BACKGROUND: About 81% of nitrous oxide ($N_2O$) emissions from agricultural land to the atmosphere is due to nitrogen (N) fertilizer application. Mitigation of $N_2O$ emissions can be more effective in controlling biochemical processes such as nitrification and denitrification in the soil rather than decreasing fertilizer application. The use of urease inhibitors is an effective way to improve N fertilizer efficiency and reduce $N_2O$ emissions. Several compounds act as urease inhibitors, but N-(n-butyl) thiophosphoric triamide (NBPT) has been used worldwide. METHODS AND RESULTS: Hot pepper and chinese cabbage were cultivated in five treatments: standard fertilizer of nitrogen-phosphorus-potassium(N-P-K, $N-P_2O_5-K_2O$: 22.5-11.2-14.9 kg/ha for hot pepper and $N-P_2O_5-K_2O$: 32.0-7.8-19.8 kg/ha for chinese cabbage), no fertilizer, and NBPT-treated fertilizer of 0.5, 1.0, and 2.0 times of nitrogen basal application rate of the standard fertilizer, respectively in Gyeonggi-do Hwaseong-si for 2 years(2015-2016). According to application of NBPT-treated fertilizer in hot pepper and chinese cabbage, $N_2O$ emission decreased by 19-20% compared to that of the standard fertilizer plot. CONCLUSION: NBPT-treated fertilizer proved that $N_2O$ emissions decreased statistically significant in the same growth conditions as the standard fertilization in the hot pepper and chinese cabbage cultivated fields. It means that NBPT-treated fertilizer can be applied for N fertilizer efficiency and $N_2O$ emissions reduction.

• International Area Studies Review
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• v.22 no.1
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• pp.215-235
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• 2018

Policy concerns related to raising fertility rates are not only common interests among the OECD countries, but they are also issues of great concern to South Korea whose fertility rate is the lowest in the world. The fertility rate in South Korea continues to decline, even though most of the national budget has been spent on measures to address this and many studies have been conducted on the increase in the fertility rates. In this regard, this study aims to verify the effectiveness of the detailed factors affecting the fertility rate that have been discussed in the previous studies on fertility rates, and to investigate the overall trend toward enhancing the quality of life and increasing the fertility rate through macroscopic and structural studies under the recognition of problems related to the policy approaches through the case studies of the European countries. Toward this end, this study investigated if a high quality of life in advanced countries contributes to the increase in the fertility rate, which country serves as a state model that has a high quality of life and a high fertility rate, and what kind of social and policy environment does the country have with regard to childbirth. The analysis of the OECD Better Life Index (BLI) and CIA fertility rate data showed that the countries whose people enjoy a high quality of life do not necessarily have high fertility rates. In addition, under the recognition that a country with a high quality of life and a high birth rate serves as a state model that South Korea should aim for, the social characteristics of Iceland, Ireland, and New Zealand, which turned out to have both a high quality of life and a high fertility rate, were compared with those of Germany, which showed a high quality of life but a low fertility rate. According to the comparison results, the three countries that were mentioned showed higher awareness of gender equality; therefore, the gender wage gap was small. It was also confirmed that the governments of these countries support various policies that promote both parents sharing the care of their children. In Germany, on the other hand, the gender wage gap was large and the fertility rate was low. In a related move, however, the German government has made active efforts to a paradigm shift toward gender equality. The fertility rate increases when the synergy lies in the relationship between parents and children; therefore, awareness about gender equality should be firmly established both at home and in the labor market. For this reason, the government is required to provide support for the childbirth and rearing environment through appropriate family policies, and exert greater efforts to enhance the effectiveness of the relevant systems rather than simply promoting a system construction. Furthermore, it is necessary to help people in making their own childbearing decisions during the process of creating a better society by changing the national goal from 'raising the fertility rate' to 'creating a healthy society made of happy families'

• Implantology
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• v.22 no.4
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• pp.242-254
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• 2018

The aim of the current study was to evaluate the results of horizontal guided bone regeneration (GBR) with xenograf t (deproteinized bovine bone mineral, DBBM), allograf t (irradiated allogenic cancellous bone and marrow), titanium membrane, resorbable collagen membrane, and advanced platelet-rich fibrin (A-PRF) in the anterior maxilla. The titanium membrane was used in this study has a three-dimensional (3D) shape that can cover ridge defects. Case 1. A 32-year-old female patient presented with discomfort due to mobility and pus discharge on tooth #11. Three months after extracting tooth #11, diagnostic software (R2 GATE diagnostic software, Megagen, Daegu, Korea) was used to establish the treatment plan for implant placement. At the first stage of implant surgery, GBR for horizontal augmentation was performed with DBBM ($Bio-Oss^{(R)}$, Geistlich, Wolhusen, Switzerland), irradiated allogenic cancellous bone and marrow (ICB $cancellous^{(R)}$, Rocky Mountain Tissue Bank, Denver, USA), 3D-titanium membrane ($i-Gen^{(R)}$, Megagen, Daegu, Korea), resorbable collagen membrane (Collagen $membrane^{(R)}$, Genoss, Suwon, Korea), and A-PRF because there was approximately 4 mm labial dehiscence after implant placement. Five months after placing the implant, the second stage of implant surgery was performed, and healing abutment was connected after removal of the 3D-titanium membrane. Five months after the second stage of implant surgery was done, the final prosthesis was then delivered. Case 2. A 35-year-old female patient presented with discomfort due to pain and mobility of implant #21. Removal of implant #21 fixture was planned simultaneously with placement of the new implant fixture. At the first stage of implant surgery, GBR for horizontal augmentation was performed with DBBM ($Bio-Oss^{(R)}$), irradiated allogenic cancellous bone and marrow (ICB $cancellous^{(R)}$), 3D-titanium membrane ($i-Gen^{(R)}$), resorbable collagen membrane (Ossix $plus^{(R)}$, Datum, Telrad, Israel), and A-PRF because there was approximately 7 mm labial dehiscence after implant placement. At the second stage of implant surgery six months after implant placement, healing abutment was connected after removing the 3D-titanium membrane. Nine months after the second stage of implant surgery was done, the final prosthesis was then delivered. In these two clinical cases, wound healing of the operation sites was uneventful. All implants were clinically stable without inflammation or additional bone loss, and there was no discomfort to the patient. With the non-resorbable titanium membrane, the ability of bone formation in the space was stably maintained in three dimensions, and A-PRF might influence soft tissue healing. This limited study suggests that aesthetic results can be achieved with GBR using 3D-titanium membrane and A-PRF in the anterior maxilla. However, long-term follow-up evaluation should be performed.